HomeMy WebLinkAbout4-203.E.16 SWMP CompleteArticle 4-203.E.16
Stormwater Management
Permit and Plan
Encana Oil & Gas (USA) Inc
K19NE Storage Facility
(Laydown Yard)
OAProject No. 014-2797
STATE OF COLORADO
John W. Hickenlooper, Governor
Christopher E. Urbina, MD, MPH
Executive Director and Chief Medical Officer
Dedicated to protecting and improving the health and environment of the people of Colorado
4300 Cherry Creek Dr. 5.
Denver. Colorado 60246-1530
Phone (303) 692-2000
Located in Glendale, Colorado
http://www.cdpha state ,co.us
June 21, 2012
Laboratory Services Division
8100 Lowry Blvd,
Denver, Colorado 80230-6928
(303) 692-3090
Cindy Allen, EHS Team Lead
Encana Oil & Gas (USA) Inc
370 17 St Ste 1700
Denver, CO 80202
RE: Renewal of Permit/Certification
Administrative Continuation
For: Mamm Creek
Located at: See Map In File, Uninc, Garfield County
Permit No.: C0R034840
Dear Mr. Allen;
Colorado Department
of Public Health
and Environment
The Division has received an application to renew the above perfrtiticertificatian. It has been determined
that there is sufficient information to make this permit/certification eligible for renewal. More information
may be requested by the Division as progress is made in developing a new permit/certification for the
above listed facility. This informationmust be made available to the Division when requested to complete
the permit process.
The Division is currently in the process of developing a new permit or master general permit and
associated certification for the above permitted facility. The development and review procedures required
by law have not yet been completed. When the discharge permit issued to you for your facility expired on
June 30, 2012 your permit is administratively continued and remains in effect udder Section 104(7) of the
Administrative Procedures Act, C.R.S. 1973, 24-4-101, etsept. (1982 repl. vol... 10) until the new
permit/certification is issued and effective.
All effluent permit terms and conditions in your current permit will remain in effect anti] your new
permit/certification is issued and effective.
PLEASE KEEP THIS LETTER WITH YOUR PERMIT AND SWMP TO SHOW
CONTINUATION OF PERMIT COVERAGE.
Sincerely,
Debbie Jessop
Permits Section
WATER QUALITY CONTROL DIVISION
xc: Permit File
encana..
natural gas
Master Stormwater
Management Plan
Mamm Creek
Volume 1
COR -034840
encana.
gas
Permit Area
Mamm Creek
Permit Number
COR -034840
SWMP REVISIONS
Date
Description
Initials
11/24/2010
Update Legal and Local Contacts
KK
11/24/2010
Updated company name from EnCana to Encana
KK
11/24/2010
Inserted Oil and Gas Construction Field Permit Certification NOTICE OF
AMENDMENT OF PERMIT COVERAGE in the place of the Final Stabilization
Certification - Appendix F
KK
Prepared by:
EnCana Oil & Gas (USA) Inc.
Parachute, Colorado
Volume 1
Master Stormwater Management
Mamm Creek`�
COR -034840 �`
EnCana Oil & Gas (USA Inc.
Updated June 2009
Prepared by:
EnCana Oil & Gas (USA) Inc.
Parachute, Colorado
Volume 1
Master Stormwater Management Plan
r
Mamm Creek
COR -034840
Prepared : c Env 8,� ental Field Coordinator
Reviewed By Ryan Meath, Environmental Field Coordinator
EnCana Oil & Gas (USA) Inc.
Updated June 2009
Contents
1.0 Introduction 1-1
1.1 Site Specific Records 1-1
1.2 SWMP Administrator 1-2
2.0 Narrative Description of Master SWMP Permit Coverage Area 2-1
2.1 Sequence of Major Activities 2-1
2.1.1 Well Pads and Roads 2-1
2.1.2 Pipelines 2-2
2.1.3 Compressor Stations, Treatment Facilities, or Other Facilities. 2-4
2.2 Area Estimates 2-6
2.3 Description of Existing Topography and Soils 2-6
2.4 Description of Existing Vegetation 2-6
2.5 Identification of Potential Pollution Sources 2-9
2.6 Allowable Sources of Non-Stormwater Dischar 2-11
2.7 Receiving Water 2-11
2.8 Master SWMP Permit Area Map and Individual Stprmw Sit- s 2-11
3.0 Best Management Practices (BMPs) 3-1
3.1 Erosion, Drainage, and Sediment Control BMPs 3-1
3.2 Non-Stormwater Control BMPs 3-1
3.2.1 Materials Delivery and Storage 3-2
3.2.2 Material Handling and Spill Prevention 3-2
3.2.3 Vehicle Cleaning, Fueling, Maintenance, and Tracking Controls 3-2
3.2.4 Waste Management and Disposal 3-3
3.2.5 Dewatering 3-3
3.3 Stormwater Manual of BMPs 3-4
3.4 Phased BMP Implementation 3-5
4.0 Interim Reclamation and Final Stabilization 4-1
5.0 Inspection and Maintenance 5-1
5.1 Inspection Schedule 5-1
5.1.1 Minimum Inspection Schedule for active sites 5-1
5.1.2 Post -Storm Event Inspections at Temporarily Idle Sites 5-1
5.1.3 Completed Sites 5-1
5.1.4 Winter Conditions Inspections Exclusion 5-2
5.2 Performing Inspections 5-2
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5.3 Maintenance 5-2
5.4 Documenting Inspections and Maintenance 5-3
6.0 Plan Revisions and Retention 6-1
7.0 Inactivation Notice 7-1
8.0 Signature 8-1
9.0 References 9-1
List of Appendices
Appendix A General Permit Application
Appendix B Revegetation Manual
Appendix C Existing Soil and Vegetation Data
Appendix D Master SWMP Permit Area Map
Appendix E Stormwater Manual of Best Management Practices (BMPs)
Appendix F Oil and Gas Construction Field Permit Certification NOTICE OF AMENDMENT OF PERMIT
COVERAGE and/or Final Stabilization Certification
Appendix G Inspection and Maintenance Report Form
Appendix H Inactivatio
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1.0 Introduction
This Master Stormwater Management Plan (Master SWMP) satisfies the Colorado Department of Public
Health and Environment (CDPHE) Water Quality Control Division (WQCD) General Permit No. COR -030000
issued on May 31, 2007 for Stormwater Discharges Associated with Construction Activities (the Stormwater
Construction Permit). EnCana Oil & Gas (USA) Inc. (EnCana) has submitted a General Permit Application to
WQCD, a copy of which is provided as Appendix A.
This Master SWMP has been prepared in compliance with CDPHE WQCD, the Federal Clean Water Act
(CWA), and the National Pollutant Discharge Elimination Permit (NPDES) regulations found in 40 CFR,
Part 122.26 for stormwater discharges.
The objectives of this Master SWMP are to:
1. Identify all potential sources of pollution which may reasony be xper ed fo • - quality of
stormwater discharges associated with construction activity within this =ster S • it area at
each project site;
2. Describe the practices to be used to reduce the pollutants in stormw discharges associated with
construction activity within this Master SWMP permit area at each proj -t site (also known as Best
Management Practices (BMPs)); and ensure the practices are selected and described in accordance
with good engineering practices, including the installation, implementation and maintenance
requirements;
3. Be properly prepared and updated to ensure compliance with the terms and conditions of the
Stormwater Construction Permit;
4. Work hand in hand with the Site Specific Records, as described in the following section; and
5. Serve as an education tool and comprehensive reference/guide to stormwater management for
inspectors, surveyors, engineers, and EnCana employees and contractors.
EnCana construction activities fall under one of two types. Exploration and Production (E&P) sites involve the
construction of well pads, roads, and other facilities. Midstream Services (also referred to as Gas Gathering)
sites involve the construction of pipelines and compressor, treatment, and other facilities. This Master SWMP
is intended to address stormwater management for any and all of these sites within this Master SWMP's
Permit Coverage Area.
1.1 Site Specific Records
While Volume 1 of the Master SWMP contains all of the general permit area information, Volume 2 of the
Master SWMP contains all of the Site Specific Records including all Individual Stormwater Site Plans (Site
Plans), as discussed in Section 2.8, and all Inspection and Maintenance Reports (discussed in Section 5.4).
These Site Specific Records contain information specific to each site (each well pad, compressor station,
section of road/pipeline, etc.), including information on areas of disturbance, ecosystems and vegetation, soil
types, percent pre -disturbance vegetation, etc. Any changes to the design of individual sites or the BMPs
used at those sites will be noted on the Site Plans as those changes occur, and kept with the Site Specific
Records.
The Site Specific Records (Volume 2 of the Master SWMP) are bound separately from the body of this Master
SWMP; however, both are readily available during any inspection. Both the body of this SWMP (Volume 1)
and the Site Specific Records (Volume 2) comprise the entire SWMP, and go hand in hand in keeping EnCana
in compliance with stormwater regulations. The Site Specific Records will be kept at the EnCana field office in
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Parachute during active construction and site inspections to ensure accurate implementation, inspections, and
maintenance of BMPs, as well as timely revisions to the Site Specific Records.
1.2 SWMP Administrator
The SWMP Administrator is responsible for the process of developing, implementing, maintaining, and revising
this SWMP as well as serving as the comprehensive point of contact for all aspects of the facility's SWMP.
SWMP Administrators:
• Local Contact:
• Legal Contact:
Kathy Kiloh, Surface Management Lead
2717 County Road 215, Suite 100, Parachute, CO 81635
(970) 285-2626
Brant Gimmeson, Group Lead EH&S South Rockies
370 17th St. Suite 1700, Denver, CO 80202
(720) 876-5030
Illigb \'' \r
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2.0 Narrative Description of Master SWMP Permit Coverage Area
Name of Permit Coverage Area: Mamm Creek Unit
Permit Number: COR -034840
Location of the Permit Coverage Area:
• County: Garfield and Mesa County.
• City: Located in Colorado approximately 1 mile south of Rifle and south of the
the southern portion of the Piceance Basin.
• Township/Section/Range: Township 6S, 7S, & 8S, Range 92W, 93W, & 94W,
sections, Sixth Principal Meridian.
Activities at the Permit Coverage Area will likely involve the construction of:
• Well pads
• Access roads
• Pipelines
• Compressor stations
• Water Treatment Facility
• Fresh Water Storage Pond
• Evaporation Facility
1'
Colorado River within
portions or all of 113
The above construction activities are only typical andie
ay vary once construction begins. Up-to-date
information on the construction of well pa roads, lines, etc. will be kept with the Site Specific Records
(Volume 2 of the Master SWMP).
2.1 Sequence of Major Activities
Site specific, scheduling, surface use agreements, and/or other constraints can and/or may dictate changes in
construction sequences. Significant sequence changes are addressed in the Site Specific Records (Volume 2
of the Master SWMP). Specific details on the construction and maintenance of BMPs mentioned below are
provided in the Stormwater Manual of Best Management Practices (BMP Manual) as discussed in Section 3.3.
1
2.1.1 Well Pads and Roads
Construction activities for well pads and roads are generally completed in the following sequence:
Preconstruction:
1. Surveys. Topographic, vegetation, wildlife and archeology, as dictated.
2. Temporary BMP's. Where physical access is available, installation of terminal perimeter and
temporary sediment controls, such as wattles, silt fence and/or other as necessary. Actual BMPs
used for each site are shown on the Site Plans (discussed in Section 2.8) and kept with the Site
Specific Records (Volume 2 of the Master SWMP).
Construction:
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3. Vegetation Clearing. Vegetation will be cleared/grubbed and placed along the perimeter at the
terminal discharge edges/points in a windrow and/or dam beyond the edge of excavation and at any
run -on -protection discharge points, and/or chipped or other depending on landowner requirements.
4. Diversions and Retention Reservoirs. After vegetation clearing and prior to topsoil stockpiling,
diversions are to be placed for run -on -protection (ROP) to prevent the greater landscape from
discharging onto the planned disturbance. Temporary sediment control BMPs shall be placed at the
discharge points of the ROP until permanent erosion controls can be installed along the entire
length of the ROP. Diversions are to be installed along the terminal discharge edge inside of the
vegetation windrows to convey site water/sediment to terminal discharge points where rough
retention reservoirs are to be installed. The retention reservoir outlets are to receive temporary
sediment control BMPs until permanent retention reservoirs and erosion, drainage, and sediment
BMPs can be installed.
5. Topsoil Stripping/Conservation. All ACCESSIBLE TOPSOIL is to be removed from areas that are
to be excavated, covered in subsoils, or turned into stabilized unpaved surfaces. If initial topsoil
stockpile areas are insufficient to accommodate the quantities of topsoil being generated, the excess
is to be placed at either end of the subsoil stockpile and segregated as much as possible. After major
earthwork, grading, and erosion/drainage/sediment controls are complete, any areas that can be
identified for immediate interim reclamation shall receive topsoil.
6. General Rough Grading. The site location will be graded tillprovide suitable surfaces for vehicle
traffic and/or building sites, and may be graded to establish urace drainage patterns, such as berms
or roadside ditches as necessary.
7. Facility Specific Grading. Individual facilities may require additional excavation to allow for
construction of foundations. Excess soil will typically be used in general site grading.
8. Foundation Construction. To support facilities (such as tanks, processing equipment, etc),
foundations will be constructed. Foundations may consist of select backfill, concrete spread footings,
or piles. Finished support elevations are to be installed twelve to eighteen inches (12-18") above
finished grade or the lowest point of the facility.
9. Facility Construction. Tanks, processing equipment, etc. will be constructed.
Interim Reclamation:
10. Gravel Surfacing. Areas used for access, parking, or materials staging will typically be gravel
surfaced.
11. Reclamation of Unused Areas. Areas not needed for facilities, roads, parking, or materials staging
will generally be reclaimed. Salvaged topsoil will be spread and the vegetative seed mix will be
applied
12. Application of Erosion Stabilization. Depending on terrain (e.g. steep slopes and drainage
crossings) additional measures may be applied to increase stability of the reclaimed area.
Final Reclamation:
13. Reclamation of Post -Operation Areas. When operation of well pad or road is no longer necessary,
the area will be decommissioned and all newly disturbed areas will be reclaimed. Any remaining
topsoil will be spread and the vegetative seed mix will be applied. This may occur after termination of
this permit and under the coverage of a new construction permit.
2.1.2 Pipelines
Construction activities for pipelines are generally completed in the following sequence:
Preconstruction:
1. Surveys. Topographic, vegetation, wildlife and archeology, as dictated.
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2. Mark Right -Of -Way. The construction right-of-way (ROW) will be marked prior to construction with
laths and/or flagging. Laths/flagging will be maintained throughout construction and will not be
removed until after reclamation activities have been completed.
3. Temporary BMPs. EnCana's stormwater inspectors will determine locations to install preconstruction
temporary erosion control devices, per site specific BMP installation plans and as necessary.
EnCana's contractor will maintain the erosion control structures as directed by the stormwater
inspectors throughout all phases of construction, or until permanent erosion control measures are
installed. Actual BMPs used for each site are shown on the Site Plans, which are kept with the Site
Specific Records (Volume 2 of the Master SWMP).
Construction:
4. Vegetation Clearing. If necessary, vegetation will be cleared and placed in a windrow at the edge of
the work area to be used later in reclamation activities, removed from the construction site, or
burned/chipped depending on landowner requirements. Details for windrows are provided within the
Stockpiling BMP of the BMP Manual (discussed in Section 3.3).
5. Topsoil Stripping. All ACCESSIBLE TOPSOIL (from the entire width of the right-of-way) will be
removed and temporarily stockpiled along the up -hill side of the right-of-way (if terrain grades will
allow) for later use in reclamation activities.
6. General Grading. For pipeline segments that occur in relatively rough terrain, general grading will be
conducted to create a safe and workable ground surface. This is generally done to form a relatively
level work surface on steep cross slopes and to reduce slopes in undulating terrain (arroyo and wash
crossings). The site location will be gr ed to provide suitable surfaceNor vehicle traffic and/or
building sites, and may be graded to e blish surface drainage patterns, such as berms or roadside
ditches as necessary.
7. Trench Excavation. The trench nee for piieline installa�i'on is almost always off -set in the ROW.
The surveyors may indicate the locati of the trench on their pipeline lateral. Generally, the trench will
be located in the first third of the RO . The remaining two thirds of the ROW will be used for working
space. The trench depth and width will vary with the number of pipes to be installed and the pipe
diameter. Generally, a 4 -foot deep trench will be excavated by track -mounted excavators. The ditch
will be excavated and sloped in accordance with OSHA specifications. The cover from top of pipe to
ground level will be a minimum of 36 inches. Where rock is encountered, tractor -mounted mechanical
rippers or rock trenching equipment may be used to facilitate excavation. The trench will be excavated
and subsoil material stockpiled within the confines of the approved right-of-way limits. Trench spoil will
be stored in a separate location from the previously segregated topsoil.
8. Pipe Installation. Pipe installation will include stringing, bending for horizontal or vertical angles in
the alignment, welding the pipe segments together, coating the joint areas to prevent corrosion, and
then lowering -in and padding.
9. Stringing. Pipe will be hauled by truck to the pipeline ROW. Each joint of pipe will be unloaded and
placed parallel to the ditch.
10. Bending. After the joints of pipe are strung along the ditch, individual joints of pipe may need to be
bent to accommodate horizontal and vertical changes in direction. Field bends will be made utilizing a
hydraulically operated bending machine. Where the deflection of a bend exceeds the allowable limits
for a field -bent pipe, factory (induction) bends will be installed.
11. Welding. After the pipe joints are bent, the pipe is lined up end-to-end and clamped into position. The
pipe is then welded in conformance with 49 CFR Part 192, Subpart E. "Welding of Steel Pipelines"
and API 1104, "Standard for Welding Pipelines and Related Facilities".
12. Welding Inspection. Welds will be visually inspected by a qualified inspector. Any defects will be
repaired or cut out as required under the specified regulations and standards.
13. Coating. To prevent corrosion, the pipe will be externally coated with fusion bonded epoxy coating
prior to delivery. After welding, field joints will be coated with fusion bond epoxy coating, tape and
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primer, or shrink sleeves. Before the pipe is lowered into the ditch, the pipeline coating will be visually
inspected and tested with an electronic detector, and any faults or scratches will be repaired.
14. Lowering -In and Padding. Once the pipe coating operation has been completed, a section of the
pipe will be lowered into the ditch. Side -boom tractors may be used to simultaneously lift the pipe,
position it over the ditch, and lower it in place. Inspection will be conducted to verify: that minimum
cover is provided; the trench bottom is free of rocks, debris, etc.; external pipe coating is not damaged;
and the pipe is properly fitted and installed into the ditch. Specialized padding machines will be used
to sift soil fines from the excavated subsoil to provide rock -free pipeline padding and bedding. In rocky
areas, padding material or a rock shield will be used to protect the pipe. Topsoil will not be used to pad
the pipe. At the completion of lowering -in and padding activities the contractor may install trench
breakers around the pipelines to minimize subsurface water flow. Details for trench breakers are
provided within the BMP Manual (discussed in Section 3.3).
15. Backfilling. Backfilling will begin after a section of the pipe has been successfully placed in the ditch
and final inspection has been completed. Backfilling will be conducted using a bulldozer, rotary auger
backfill, padding machine or other suitable equipment. Backfilling the trench will use the subsoil
previously excavated from the trench. Backfill will be graded and compacted, where necessary for
ground stability, by being tamped or walked in with a wheeled or track vehicle. Compaction will be
performed to the extent that there are no voids in the trench. Any excavated materials or materials
unfit for backfill will be utilized or properly disposed of in conformance with applicable laws or
regulations.
16. General Grading. If general grading was conducted to facilitate pipeline construction, these materials
will be replaced and graded to recreate the preconstruction topography.
Final Reclamation:
17. Cleanup. Cleanup activities will be initiated as soon as practicable after backfilling activities have
been completed. All construction -related debris will be removed and disposed of at an approved
disposal facility.
18. Subsoil and Topsoil Placement. Subsoil will be evenly re-contoured across the right-of-way to
pre -construction conditions. After the subsoil has been re -spread the contractor will spread the
previously segregated topsoil back across the right-of-way. The topsoil will be evenly spread to
original contours.
19. Vegetation. After any remaining topsoil is spread, the vegetative seed mix will be applied. The area
will be revegetated according to private landowner Surface Use Agreements and/or according to the
BLM/Forest Service reclamation requirements. Details for revegetation are provided within the BMP
Manual (discussed in Section 3.3) and the Revegetation Manual (provided as Appendix B).
20. Application of Erosion Stabilization. Depending on terrain (e.g. steep slopes and drainage
crossings) additional measures may be applied to increase stability of the reclaimed area. Possible
erosion stabilization methods are provided within the BMP Manual (discussed in Section 3.3). Actual
locations and measures used are shown on the Site Plans, which are kept with the Site Specific
Records (Volume 2 of the Master SWMP).
2.1.3 Compressor Stations, Treatment Facilities, or Other Facilities.
Construction activities for compressor stations, treatment facilities, and other facilities are generally completed
in the following sequence:
Preconstruction:
1. Surveys. Topographic, vegetation, wildlife and archeology, as dictated.
2. Temporary BMP's. Where physical access is available, installation of terminal perimeter and
temporary sediment controls, such as wattles, silt fence and/or other as necessary. Actual BMPs
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used for each site are shown on the Site Plans, which are kept with the Site Specific Records
(Volume 2 of the Master SWMP).
Construction:
3. Vegetation Clearing. Vegetation will be cleared/grubbed and placed along the perimeter at the
terminal discharge edges/points in a windrow and/or dam beyond the edge of excavation and at any
run -on -protection discharge points, and/or chipped or other depending on landowner requirements.
4. Diversions and Retention Reservoirs. After vegetation clearing and prior to topsoil stockpiling,
diversion are to be placed for ROP to prevent the greater landscape from discharging onto the
planned disturbance. Temporary sediment control BMP's shall be placed at the discharge points of
the ROP until permanent erosion controls can be installed along the entire length of the ROP.
Diversions are to be installed along the terminal discharge edge inside of the vegetation windrows
to convey site water/sediment to terminal discharge points where rough retention reservoirs are to
be installed. The retention reservoir outlets are to receive temporary sediment control BMP's until
permanent retention reservoirs and erosion, drainage, and sediment BMP's can be installed.
5. Topsoil Stripping/Conservation. All ACCESSIBLE TOPSOIL is to be removed from areas that are
to be excavated, covered in subsoils, or turned into stabilized unpaved surfaces. If initial topsoil
stockpile areas are insufficient to accommodate the quantities of topsoil being generated, the excess
is to be placed at either end of the subsoil stockpile and segregated as much as possible. After major
earthwork, grading, and erosion/drainage/sediment control are'pmplete, any areas that can be
identified for immediate interim reclamation shall receive topsoil
6. General Rough Grading. The site location will be graded to prove ssurfaces for building
sites and vehicle traffic, and may be g ed to establish surface drainage atterns, such as berms or
roadside ditches as necessary.
7. Excavation. Soil will be excavated to allow for the construction of foundations. Trenches will be
excavated for all underground piping and conduit. Excess soil will typically be used in general site
grading.
8. Foundation Construction. Foundations will be constructed to support facility buildings. Foundations
may consist of select backfill, concrete spread footings, piles, etc. Finished support elevations are to
be installed twelve to eighteen inches (12-18") above finished grade or the lowest point of the facility.
9. Facility Construction. Buildings, tanks, processing equipment, etc. will be constructed. Utilities will
be installed.
Interim Reclamation:
10. Landscaping. If necessary, certain areas will be spread with topsoil and landscaped.
11. Gravel Surfacing. Areas used for access, parking, or materials staging will typically be gravel
surfaced.
12. Reclamation of Unused Areas. Areas not needed for facilities, roads, parking, or materials staging
will generally be reclaimed. Salvaged topsoil will be spread and the vegetative seed mix will be
applied.
13. Application of Erosion Stabilization. Depending on terrain (e.g. steep slopes and drainage
crossings) additional measures may be applied to increase stability of the reclaimed area. Possible
erosion stabilization methods are provided within the BMP Manual (discussed in Section 3.3). Actual
locations and measures used are shown on the Site Plans, which are kept with the Site Specific
Records (Volume 2 of the Master SWMP).
Final Reclamation:
14. Reclamation of Closed Facilities. When facilities are no longer necessary, the buildings may be
demolished, according to approved procedures. All construction materials will be removed and the
newly disturbed areas will be reclaimed. Any remaining topsoil will be spread and the vegetative seed
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mix will be applied. This may occur after termination of this permit and under the coverage of a new
construction permit.
2.2 Area Estimates
The Permit Coverage Area encompasses portions or all of 113 sections of surface land (approximately
72,273 acres) in Township 6, 7, and 8 South, Range 92, 93, and 94 West. Development of the natural gas
resource and related facilities within the area is estimated to result in a total disturbance area of 999+ acres.
Because the area will vary over time, these are only approximate estimates. This information is used to help
determine the extent of control measures (BMPs) needed.
2.3 Description of Existing Topography and Soils
The Permit Coverage Area consists of relatively flat mesas and ridge crests, alluvial terraces, steep slopes,
mountainsides, intermittent drainage swells, and valley bottoms. The Mamm Creek Unit is located south of the
Colorado River, within the southern portion of the Piceance Basin. The Piceance Basin is a broad, asymmetric,
southeast -northwest trending structural basin that contains sedimentary rocks up to 20,000 feet thick and lies
between the White River uplift to the northeast, the Gunnison uplift to the south, and the Uncompahgre swell to
the west (George 1927; Weiner and Haun 1960).
Elevations within the Permit Coverage Area range from approximately 5,000 feet above mean sea level (amsl)
along the Colorado River to 8,900 feet on Grass Mesa near the western edge of the unit area. Annual
precipitation within the Permit Coverage Area ranges from 10 to 40 inches. Soils surrounding the Permit
Coverage Area are distributed according to the major soil forming factors including climate (effective moisture
and temperature), parent material, topographic position, and slope. The soils table within Appendix C provides
a summary of the soil types found within the Permit Coverage Area (including permeability, available water
capacity, surface runoff, erosion hazard, and others). Most of these soil types are considered to possess
moderate to very severe potential for water erosion.
2.4 Description of Existing Vegetation
The existing percent vegetative ground cover for each well pad, section of roadway/pipeline, etc. within the
Permit Coverage Area is estimated on each inspection and maintenance report form (discussed in Section
5.4), which are kept with the Site Specific Records (Volume 2 of the Master SWMP). A map indicating the
existing ecosystem types ,ithin the Permit Coverage Area is provided in Appendix C.
A description of the exis pg' etation within each ecosystem (Mutel, 1992) is as follows:
1. Grasslands
a. Plains Gr#lands: Plaigrasslands are dominated by a mixture of blue grama (Chondrosum
gracile) and buffalograss (Buchloe dactyloides). Interspersed are occasional shrubs and bright
flowered forbs, most of which are members of the pea and sunflower families. Taller grass
species cover 10 to 25 percent of the ground of little -grazed, moist sites. Most are perennial
bunch -grasses up to three feet tall. Needle -and -thread (Stipa comata), sand dropseed
(Sporobolus cryptandrus), side -oats grama (Bouteloua curtipendula), western wheatgrass
(Pascopyrum smithii), Junegrass (Koeleria macrantha), and red three -awn (Aristida purpurea) are
other common species. Common forbs consist of prickly pear (Opuntia polyacantha), pasture
sage (Artemisia frigida), and yucca (Yucca glauca).
b. Mountain Grasslands and Meadows. Natural wet meadows and fens are dominated by
moisture -loving species, primarily members of the sedge and rush families. Spike-rush
(Eleocharis palustris), sedges, Canadian reedgrass (Calamagrostis canadensis), and tufted
hairgrass (Deschampsia cespitosa) are common. Natural dry meadows are filled with members of
the grass family. Bunchgrasses dominate at low elevations. Needle -and -thread, mountain muhly
(Muhlenbergia montana), Junegrass, blue grama, and species of wheatgrass and bluegrass are
common. Successional meadows contain a combination of weedy, introduced plants and plants
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typical of dry, rocky slopes, such as common dandelion (Taraxacum officinale), golden banner
(Thermopsis divaricarpa), Colorado locoweed (Oxytropic sericea), mountain pussytoes
(Antennaria parvifolia), showy daisies (Erigeron speciosus), stonecrop (Sedum lanceolatum), and
some sedges (Carex ssp.). Mountain grasslands, where Thurber fescue (Festuca thurberi) and
mountain muhly were once the dominant grasses, are now largely dominated by blue grama,
Canada bluegrass (Poa compressa), foxtail barley (Critesion jubatum), and other species as a
result of grazing.
2. Riparian Ecosystems
a. Lowland Riparian Ecosystems. The lowland riparian ecosystem is dominated by the plains
cottonwood (Populus deltoidea ssp. occidentalis), the valley cottonwood (Populus deltoidea ssp.
wislizenii) and the peach -leaved willow (Salix amygdaloides). Common shrubs and herbaceous
plants include snowberry (Symphoricarpos occidentalis), sandbar willow (Salix exigua), bulrush
(Schoenoplectus lacustris), broad-leaved cat -tail (Typha latifolia), prairie cord -grass (Spartina
pectinata), and western wheatgrass.
b. Mountain Riparian Ecosystems. The mountain riparian ecosystem is dominated by quaking
aspen (Populus tremuloides), lanceleaf cottonwood (Populus X acuminata), narrowleaf
cottonwood (Populus angustifolia), and Colorado blue spruce (Picea pungens). Common shrubs
include alder (Alnus incana), river birch (Betula fontinalis), chokecherry (Padus virginiana),
common gooseberry (Ribes inerme), bush honeysuckle (Distegia involucrata), and mountain
maple (Acer glabrum). The lush riparian herbaceous understory includes forbs, grasses, sedges,
rushes, climbing vines, mosses, lichens, and liverworts. Weedy invaders are also common.
3. Shrublands. Shrub communities include semidesert shrublands found in dry lowlands, sagebrush
shrublands that occupy a wide range of elevation from the Colorado Plateau to high mountain valleys,
and montane shrublands other than sagebrush, characteristic of foothills and mountain regions.
a. Semidesert Shrublands. Common shrubs include Great Basin big sagebrush (Seriphidium
tridentatum), greasewood (Sarcdbatus vermiculatus), rabbitbrush (Chrysothamnus), four -winged
saltbush (Atriplex canescens)„,and shadscale (Atriplex confertifolia). Common grasses and forbs
include galletagrass (Hilaria jainesii), blue grama, alkali sacaton (Sporobolus airoides), nodding
eriogonum (Eriogonum cernuum), copper mallow (Sphaeralcea coccinea), and prince's plume
(Stanleya pinnata).
b. Sagebrush Shrublands. Common shrubs include Great Basin big sagebrush, mountain big
sagebrush (Seriphidium vaseyanum), rabbitbrush, and serviceberry (Amelanchier alnifolia).
Common grasses and forbs include nodding eriogonum, copper mallow, and Indian Paintbrush
(Castilleja spp.).
c. Montane Shrublands. Common shrubs include mountain mahogany (Cercocarpus), Gamble
oak (Quercus gambelii), rabbitbrush, serviceberry, and skunkbrush (Rhus aromatica). Common
grasses and forbs include needle -and -thread, western wheatgrass, copper mallow, and Indian
Paintbrush.
4. Pinyon -Juniper Woodlands. Pinyon -juniper woodlands consist of scattered Utah juniper
interspersed with big sagebrush. Pinyon pine is a minor component. Several other shrub species
also occur in this community, including snowberry, bitterbrush (Purshia tridentata), snakeweed
(Gutierrezia sarothrae), and serviceberry. In general, the sparse herbaceous layer consists of
graminoids such as cheatgrass (Anisantha tectorum), Kentucky bluegrass (Poa pratensis), western
wheatgrass, Indian ricegrass (Oryzopsis hymenoides), and squirreltail (Elymus elymoides). Forbs
include Tracy's thistle (Cirsium tracyi), mariposa lily (Calochortus nuttallii), western wallflower
(Erysimum capitatum), tapertip onion (Allium acuminatum), yarrow (Achillea lanulosa), stemless four -
nerve daisy (Tetraneuris acaulis), and sharpleaf twinpod (Physaria acutifolia). All of these are native
species, except for cheatgrass (an invasive, non-native annual species) and Kentucky bluegrass (a
widely naturalized non-native perennial species).
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5. Montane Forests
a. Ponderosa Pine Forests. These forests are dominated by the ponderosa pine (Pinus
ponderosa) and the Rocky Mountain juniper (Savina scopulorum). Common shrubs and
herbaceous plants include the wax currant (Ribes cereum), blue grama, side -oats grama,
Junegrass, needle -and -thread, spike fescue (Leucopoa kingii), and sulphur flower (Eriogonum
umbellatum).
b. Douglas Fir Forests. These forests are dominated by the Douglas fir (Pseudotsuga menziesii).
Common shrubs and herbaceous plants include common juniper (Juniperus communis),
kinnikinnik (Arctostaphylos), mountain maple (Acer glabrum), mountain lover (Paxistima
myrsinites), heart -leaved arnica (Arnica cordifolia), and false Solomon's seal (Maianthemum spp.)
c. Aspen forests. Quaking aspen generally occur on north -facing slopes, and along drainage
swales. The aspen forest generally has an understory of Wood's rose (Rosa woodsii), Colorado
blue columbine (Aquilegia caerulea), showy daisy, Thurber fescue, white geranium (Geranium
richardsonii), common lupine (Lupinus argenteus), Fendler meadowrue (Thalictrum fendleri), and
American vetch (Vicia americana).
d. Lodgepole Pine Forests. These forests are dominateby the lodgepile pine (Pinus contorta).
Common shrubs and herbaceous plants include broom huckleberry (Vaccinium scoparium),
common juniper, kinnikinnik, sticky -laurel (Ceanothus velutinus), and heart -leaved arnica.
6. Subalpine Forests
a. Engelmann Spruce and Subalpine Fir. Engelmann spruce (Picea engelmannii) and subalpine
fir (Abies bifolia) trees are the dominant species in this type of forest, however lodgepole pine,
aspen, and sedge -bluegrass have been known to invade in areas which have been severely
burned. Understory growth is patchy and consists primarily of dense, low -growing blueberry
(Vaccinium myrtillus) and broom huckleberry bushes. Moisture -loving shrubs and herbs such as
broad-leaved arnica (Arnica latifolia) and heart -leaved arnica, Jacob's ladder (Polemonium
pulcherrimum), curled lousewort (Pedicularis racemosa), elk sedge (Carex geyen), and lesser
wintergreen (PPa minor) are interspersed among the huckleberry.
b. Limber and Bristlecone Pine Woodlands. Limber pine (Pinus flexilis) and bristlecone pine
(Pinus aristata) trees are the only tree species that can invade this harsh ecosystem. Common
species among the sparse understory consist of common juniper, kinnikinnik, sticky -laurel,
Junegrass, stonecrop, Colorado locoweed, and whitlow -wort (Draba spp.). Lichens cover
exposed rock surfaces.
7. Alpine Tundra. Tundra vegetation consists of a low growth of shrubs, cushion plants, and small forbs
with brilliantly colored flowers, and of lush meadows of narrow -leaved sedges and grasses. These
plants cover gentle slopes and rock crevices filled with soil. Rock surfaces are partially covered with
more primitive plants — lichens and mosses. Shrubs consist of arctic willow (Salix arctica),
barrenground (Salix brachycarpa), planeleaf (Salix planifolia), and snow (Salix reticulate ssp. nivalis).
Common grasses are alpine bluegrass (Poa arctica), tufted hairgrass (Deschampsia cespitosa), and
kobresia (Kobresia myosuroides). The most common forbs are alpine avens (Acomastylis rossii),
American bistort (Bistorta bistortoides), marsh marigold (Psychrophila Ieptosepala), old -man -on -the -
mountain (Rydbergia grandiflora), moss pink (Silene acualis), rock selaginella (Selaginella densa), and
alpine sandwort (Lidia obtusiloba). All plant species are slow-growing perennials except for the rare
annual koenigia, a tiny member of the buckwheat family.
8. Urban Areas. Urban areas contain an increased density of human -created structures in comparison
to the areas surrounding it. Depending on the area, vegetation may account for anywhere between 20
and 70 percent of the total land cover, with the remaining portion being constructed materials. Types
of vegetation within urban areas may be any combination of the above ecosystems, and may include
areas of blue grass yards and parks.
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9. Cropland. Cropland vegetation may consist of wheat, corn, soybeans, or a variety of many other
crops. Cropland may either lie fallow (bare of any crops) or contain crops at any stage of growth from
seedlings to mature plants.
Detailed Description of Existing Vegetation
The existing percent vegetative ground cover for each well pad, section of roadway/pipeline, etc. within the
Permit Coverage Area is estimated on each inspection and maintenance report form (discussed in
Section 5.4), which are kept with the Site Specific Records (Volume 2 of the Master SWMP). The primary
vegetation types in the Mamm Creek Unit are sagebrush shrublands (Artemisia tridentata), pinyon -juniper
woodlands (Pinus edulis-Juniperus osteosperma), and Gambel oak shrublands (Quercus gambelii). A small
amount of aspen is present at the southern and eastern edge of the Project Area. The riparian vegetation
includes narrowleaf cottonwood (Populus angustifolia), mountain maple (Acer glabrum), river birch (Betula
occidentalis), alder (Alnus incana spp. tenuifolia), dogwood (Cornus sereciea), and Woods' rose (Rosa
woodsii). Snowberry occurs in the shrublayer, and orange sneezeweed (Dugaidia hoopesii), tailcup lupine
(Lupinus caudatus), field horsetail (Equisetum arvense), American vetch (Vicia americana), orchardgrass
(Dactylis gloverata), northern bedstraw, geranium (Geranium caespitosum), and yarrow (Achillea lanulosa)
occur in the understory. Further to the southwest, numerous blue spruce (Picea pungens) occur along the
creek (BLM 2005).
Vegetation within the Grass Mesa area primarily consists of hillsides dominated by pinyon -juniper
woodlands (Juniperus osteosperma and Pinus edulis) and the mesa top dominated by mixed mountain
shrubs, mostly big sagebrush (Artemisia tridentata), Gambel oak (Quercus gambelii), and serviceberry
(Amelanchier alnifolia). Several of the proposed locations fall within areas dominated by sagebrush -steppe.
Herbaceous and succulent species commonly found in the project area include arrow -leaf balsamroot
(Balsamorhiza sagittata), prickly pear cactus (Opuntia polyacantha), prairie lupine (Lupinus wyethii), orange
globemallow (Sphaeralcea munroana), and several species of penstemon (Penstemon spp.) and paintbrush
(Castilleja spp.) (BLM 2004).
The entire Mamm Creek Unit has, to some extent, been affected by cheatgrass (downy brome) (Bromus
tectorum) (see Invasive, Non -Native Species). It is often associated with sagebrush communities and
disturbed areas, especiallu two -track roads. In the pinyon/juniper woodlands, this species may be found as the
understory.
Stressed by the recent drought, many pinyon pine trees in the Colorado Plateau have succumbed to an
engraver beetle (Ips confusus) infestation. However, in the Mamm Creek Unit, the scattered pinyon pine trees
have shown few signs of infestation.
2.5 Identification of Potential Pollution Sources
Potential sources of pollution are associated with all phases of the project from the start of construction though
interim reclamation and up until final stabilization has occurred. Final stabilization occurs when construction
activities have been completed and all disturbed areas have been either built on, paved, or a uniform
vegetative cover has been established with a density of at least 70 percent of pre -disturbance levels, or
equivalent permanent, physical erosion reduction methods have been employed.
The most common source of pollution during construction is sediment resulting from the erosion of recently
cleared and/or graded areas, such as cut/fill slopes and soil stockpiles. However, there may be many potential
pollution sources at any given site. The following types of conditions that might affect the potential for a
pollutant source to contribute pollutants to stormwater (CDPHE, 2007B) shall be evaluated:
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• The frequency of the activity (i.e., does it occur every day or just once a month? can it be scheduled to
occur only during dry weather?);
• Characteristics of the area where the activity takes place (i.e., surface type (pavement, gravel,
vegetation, etc.), physical characteristics [site gradients, slope lengths, etc.]);
• Ability of primary and secondary containment (fuel tanks, drum storage, etc.) at product storage and
loading/unloading facilities to prevent and contain spills and leaks;
• Proximity of product storage and loading/unloading facilities to waterways or drainage facilities;
• Concentration and toxicity of materials which may to be found in the site's stormwater runoff; and
• Contamination of storage facilities/containment with stored materials (i.e., used oil drums or tanks
coated with spilled oil).
The following items are potential sources of pollutants at the Mamm Creek Unit. Each of the potential sources
of pollutants will be controlled using one or more of the following types of BMPs: Erosion Controls, Drainage
Controls, Sediment Controls or Non-Stormwater Controls. Descriptions and details for each of these types of
BMPs are provided in the BMP Manual (discussed in Section 3.3). Actual BMPs used at each site are shown
on the Site Plans (discussed in Section 5.4).
Construction:
• All Disturbed and Stored Soils: Erosion Controls, Drainage Controls, Sediment Controls.
• Vehicle Tracking of Sediments: Sediment Controls, Non-Stormwater Controls.
• Management of Contaminated Soils: Non-Stormwater Control
• Loading and Unloading Operations: Non-Stormwater C
• Outdoor Storage Activities (Building Materials, Fertilizers, icals, etc.): Non-Stormwater Controls.
• Vehicle and Equipment Maintenance and F ieling: Non-Strmwater Controls.
• Significant Dust or Particulate Generat[ng Processes: Non-Stormwater Controls.
• Routine Maintenance Activities Involving Fertilizers, Pesticides, Detergents, Fuels, Solvents, Oils, etc.:
Non-Stormwater Controls.
• On -Site Waste Management Practices (Waste Piles, Liquid Wastes, Dumpsters, etc.):
Non-Stormwater Controls.
VVI
• Concrete Truck/Equipment ing, Including the Concrete Truck Chute and Associated Fixtures
and Equipment: Non-Stormwater Controls.
• Dedicated Asphalt and Concrete Batch Plants: There will be no asphalt or concrete batch plants
located within the Permit Coverage Area of this SWMP.
• Non -Industrial Waste Sources Such as Worker Trash and Portable Toilets: Non-Stormwater Controls.
Interim/Final Reclamation:
• All Disturbed and Stored Soils: Erosion Controls, Drainage Controls, Sediment Controls.
• Vehicle Tracking of Sediments: Sediment Controls, Non-Stormwater Controls.
• Vehicle and Equipment Maintenance and Fueling: Non-Stormwater Controls.
• Significant Dust or Particulate Generating Processes: Non-Stormwater Controls.
• Non -Industrial Waste Sources such as Worker Trash and Portable Toilets: Non-Stormwater Controls.
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2.6 Allowable Sources of Non-Stormwater Discharge
Allowable sources of non-stormwater discharge within the Permit Coverage Area include the following:
• Uncontaminated Springs. Although there are several springs within the Permit Coverage Areas,
none of these springs are currently located in areas where soil disturbance will occur. If this changes
in the future, the controls used at any such location will be noted with the Site Specific Records.
• Landscape Irrigation Return Flow. There are several locations where pipelines cross through
irrigated fields. These locations will be treated similarly to any water crossing with the use of an
appropriate control which will be noted in the Site Specific Records.
• Construction Dewatering. Construction dewatering is described and discussed in Section 3.2.5.
• Concrete Washout. Concrete washout is described and discussed in Section 3.2.4.
• Emergency Fire Fighting Water. Water used to put out any type of fire is considered an allowable
source of non-stormwater discharge.
No other non-stormwater discharges are allowed under the Stormwater Construction Permit. Other types of
non-stormwater discharges must be addressed in a separate permit issued for that discharge.
2.7 Receiving Water
Runoff from disturbed areas during construction will be controlled and/or routed through the use of one or
more BMPs, as described later in this plan, prior to being discharged to receiving waters. However, it may be
expected that runoff from certain areas will into the earth and is not expected to contribute to receiving
waters.
All streams in the Mamm Creek Unit are tribiTfary to the Colorado River. The project area is located in the
Mamm Creek watershed, and drained by Gant Gulch, Middle Mamm Creek, and an unnamed tributary to
Middle Mamm Creek. Gant Gulch is tributary to West Mamm Creek. These drainages flow to the northeast
into the mainstream portion of Mamm Creek. Mamm Creek is a perennial tributary to the Colorado River.
Floodplain habitat occurs along Middle Mamm Creek and East Mamm Creek, which are perennial streams
within the Gant Gulch Area. Dry Hollow Creek is also within the Project Area. Riparian habitat is found along
the banks of these streams. The riparian vegetation along Middle Mamm creek extends up to 100 feet on
either side of the creek. The riparian habitats associated with Middle Mamm, East Mamm and Dry Hollow
Creeks, have been determined to be "non-functional" or "functioning at risk" (M. Kinser, BLM, personal
communication, September 2005) (BLM 2005).
The Grass Mesa area is located within the watersheds of Dry Creek and Ramsey Gulch. Both of these
creeks are tributaries to the Colorado River. Stream flows in the drainages within the Grass Mesa area are
generally ephemeral and dependent on seasonal storm and snowmelt runoff. Floodplain habitats occur
along the intermittent drainages within Dry Creek and Ramsey Gulch but no floodplain habitat would be
impacted by the proposed action. Intermittent drainages occur along Dry Creek and Ramsey Gulch.
However, no wetland habitats or riparian vegetation have been documented along these drainages (BLM
2004)
2.8 Master SWMP Permit Area Map and Individual Stormwater Site Plans
An overall Master SWMP Permit Area Map is provided as Appendix D. This map is likely to change constantly
and will be updated at least annually. The Master SWMP Permit Area Map includes:
• Contours and elevations (topography) with existing drainage patterns;
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• Locations and names of major surface waters such as streams, wetlands, irrigation ditches, canals,
etc.,
• Master SWMP permit area boundaries;
• Construction area locations including roads, pipelines, well pads, compressor station facilities,
treatment facilities, water parks, and all other facilities.
Individual Stormwater Site Plans (Site Plans) of each site (well pad, access road, section of pipeline, etc.) are
provided with the Site Specific Records (Volume 2 of the Master SWMP) Separate Site Plans will be
developed for each phase of construction: preconstruction, construction, interim reclamation (if applicable),
final stabilization (if applicable) and final reclamation (if applicable). These Site Plans include:
• Construction site boundaries (this is the area expected to be disturbed by clearing, excavating,
grading, or other construction activities);
• Contours and elevations (topography) with existing and propos drainage patterns;
• Limits of well pads and locations of reserve pits and well h (i pplible);
• All areas of ground surface disturbance, including areas of cut fill;
• Locations of all potential pollutant sources listed in Section 2.5 (including areas used for vehicle
fueling, the storage of materials, equipment, soil, or waste, etc...);
• Locations of all minor surface waters and all anticipated allowable sources of non-stormwater
discharge (including springs, dewatering, concrete washout, etc...);
• Locations of all existing and planned BMP#Ohcludingerosion, drainage, and sediment controls);
i
• Locations, names, distances to wetlaids, irrigation ditches, canals, other surface waters, etc;
• The size, type and location of any ouffall(s). If the stormwater discharge is to a municipal separate
stormwater system, name that system, the location of the storm sewer discharge, and the ultimate
receiving water(s).
Figures showing typical BMP locations along roadways and pipelines are provided as part of the BMP Manual
(discussed in Section 3.3).
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3.0 Best Management Practices (BMPs)
A key component of this Master SWMP is employing BMPs to improve stormwater quality. Local factors will
be evaluated to determine what BMPs are suitable and practical at different locations. BMPs will be employed
in different combinations during construction activities and phases as conditions warrant. Due to the fact that
this Master SWMP is likely to cover more than one ecosystem (as described in Section 2.4), the selection of
BMPs (including type, quantity, sequence/combination, etc.) will vary at each site within the Master SWMP
Permit Area. Specific BMPs to be employed at each well pad, road, pipeline, or other facility are identified on
the Site Plans, which are kept with the Site Specific Records (Volume 2 of the Master SWMP).
3.1 Erosion, Drainage, and Sediment Control BMPs
The primary method for controlling erosion, drainage, and sediment transport consists of minimizing initial
disturbance of the soil and ground cover. However, many other methods can also be used. All stormwater-
related BMPs will fall under at least one of the following three types of controls:
• Erosion Control. Any source control practice that protects the soil surface and/or strengthens the
subsurface in order to prevent soil particles from being detached by rain or wind, thus controlling
raindrop, sheet, and/or rill erosion.
• Runoff Control. Any practice that reduces or eliminates gully, channel, and stream erosion by
minimizing, diverting, or conveying runoff.
• Sediment Control. Any practice that traps the soil particles after they have been detached and
moved by wind or water. Sediment control measures are usually passive systems that rely on
filtering or settling the particles out of the water or wind that is transporting them prior to leaving
the site boundary.
BMPs may also be classified as either structural or non-structural controls:
• Structural Control. Handles sediment -laden stormwater prior to it leaving each site. Structural
BMPs are used to delay, capture, store, treat, or infiltrate stormwater runoff. Some examples of
structural BMPs include sediment traps, diversions, and silt fences. Most Runoff Controls and
Sediment Controls can also be classified as Structural Controls.
• Non-structural Control. Reduces the generation and accumulation of pollutants, including sediment,
from a construction site by stabilizing disturbed areas and preventing the occurrence of erosion.
Some examples of non-structural BMPs include revegetation, mulching, and surface roughening.
These types of stabilization techniques are not only the most effective method for reducing soil loss,
but they are also normally the most cost effective due to low initial cost and reduced maintenance
requirements. Most, but not all, Erosion Controls can also be classified as Non-structural Controls.
The Site Plans, as mentioned previously and kept with the Site Specific Records (Volume 2 of the Master
SWMP), show the proposed locations of all erosion, drainage, and sediment control BMPs (both structural and
non-structural). Detailed descriptions, design criteria, construction specifications, and maintenance
information for all BMPs are provided in the BMP Manual (discussed in Section 3.3).
3.2 Non-Stormwater Control BMPs
Non-stormwater controls include general site and materials management measures that indirectly aid in the
minimization of water pollution. Types of pollution sources include, but are not limited to, litter, oil and grease,
hazardous material spills, and sediment.
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3.2.1 Materials Delivery and Storage
The good housekeeping practices listed below will be followed on site during construction and operation:
• An effort will be made to store only enough product required for task completion.
• All materials stored on site will be stored in a neat and orderly manner in appropriate containers and,
where possible, under a roof or other enclosure, and/or within secondary containment areas to avoid
contact with stormwater.
• Products will be kept in their original containers with the original manufacturer's label.
• Substances will not be mixed with one another unless recommended by the manufacturer.
• Whenever possible, all of the product will be used before disposing of the container.
• Manufacturer's recommendations for proper use and disposal will be followed.
Additional information on material delivery and storage is available in the BMP Manual (discussed in
Section 3.3).
3.2.2 Material Handling and Spill Prevention
In addition to the material storage practices (listed in the previous section) that will be used to reduce the risk
of spills or other accidental exposure of materials and substance, the BMP Manual (discussed in Section 3.3)
will provide more detailed information on spill prevention and control. Furthermore, the Spill Prevention,
Control and Countermeasure (SPCC) Plan will be followed for the control of hydrocarbons. In general, spill
prevention and response procedures will include notification (CDPHE 24-hour spill reporting line — 877-518-
5608), clean-up with the use of spill kits and absorbents, and ensuring that materials and wash water can not
discharge from the site, and never into a storm drain system or stream.
3.2.3 Vehicle Cleaning, Fueling, Maintenance, and Tracking Controls
As required by EnCana Oil & Gas (USA), Inc. master service agreement(s) and drilling contract(s), contracting
companies and/or vendors are required to service all vehicles and equipment prior to entering EnCana
facilities. However, in the event maintenance procedures are required at EnCana facilities, all fluids
transferred must utilize secondary containment and drip pans to minimize a release of materials and properly
dispose or recycle spent materials in compliance with local, state, and federal guidelines.
While on site, equipment will be parked, serviced, and fueled within designated areas. Equipment fueling on
pipeline rights-of-way will be mobile during active construction. Periodic inspections of equipment and control
procedures will be implemented. Selected equipment may be fueled in place using fuel trucks. When
necessary, equipment and machinery will be decontaminated at an on-site decontamination area prior to
removal from the construction area. Areas will be provided with adequate waste disposal receptacles for liquid
as well as solid waste.
Vehicle tracking of sediments is not expected to be a problem due to construction scheduling. Construction
vehicles will remain on site throughout earth -moving activities. All other vehicles remain in stabilized areas
and do not enter the construction area until that area is stabilized. However, applicable BMPs (such as
scheduling (to minimize site access), stabilized construction entrances, vehicle cleaning, etc.) will be utilized if
sediment tracking does become a problem.
In addition to the typical practices listed above, the BMP Manual (discussed in Section 3.3) provides more
detailed information on vehicle cleaning, fueling, maintenance, and tracking controls.
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3.2.4 Waste Management and Disposal
As required by EnCana Oil & Gas (USA), Inc. master service agreement(s) and drilling contract(s), contracting
companies and/or vendors are required to manage all waste generated by their activities at EnCana facilities in
compliance with local, state, and federal guidelines. EnCana Oil & Gas (USA) utilizes a periodic inspection
program to ensure waste management requirements are fulfilled and inspections are documented.
A few of the waste management procedures that will be followed include the following:
• Proper bins will be provided for trash collection and disposal in compliance with local, state, and
federal guidelines.
• Contaminated soils will be placed into a lined and bermed area. Samples of the impacted soil will be
collected and a complete characterization analysis will be performed. When applicable, the impacted
soil will be sent to a licensed disposal facility.
• The contractor will provide portable toilets. Sanitary waste will be regularly collected by a licensed
sanitary waste management contractor and disposed of in an approved manner.
• In the event that sediment is inadvertently transported off the construction site, it will be collected and
returned to the site and placed on the soil stockpile or spread over the construction pad area and
compacted.
On well pads and access roads concrete washout is used as an interior conductor pipe ballast. Concrete
washout water can NOT be discharged to surface waters or to storm sewer systems without separate permit
coverage. However, discharge to the ground of concrete washout water from washing of tools and concrete
mixer chutes may be authorized by this permit, provided that (CDPHE, 2007a):
1. The source is identified in the SWMP;
2. BMPs are included in the SWMP to prevent pollution of groundwater; and
3. These discharges do not leave the site as surface runoff or to surface waters.
Locations where concrete washout activities take place are shown on the Site Plans.
Additional waste management proceduincluding solid waste, hazardous waste, contaminated soil,
concrete washout, and septic and sanitary waste, are included in the BMP Manual (discussed in Section 3.3).
3.2.5 Dewatering
Dewatering refers to the mechanical removal of water from an excavation or other structure. Both
groundwater and stormwater may require dewatering during construction. Dewatering of pipelines at the
completion of hydrostatic testing will be required for most pipeline installations.
3.2.5.1 Groundwater Dewatering
Groundwater is very rarely encountered during the construction activities associated with either E&P sites or
Midstream Services sites. If groundwater is encountered, it is typically during construction of a pipeline across
a stream crossing. These pipelines are either bored under the stream or a flume is utilized.
Non-stormwater construction dewatering of groundwater can NOT be discharged to surface waters or to storm
sewer systems without separate permit coverage. However, discharges to the ground of water from
construction dewatering activities may be authorized by this permit, provided that (CDPHE, 2007a):
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1. The source is groundwater and/or groundwater combined with stormwater that does not contain
pollutants in concentrations exceeding the State groundwater standards in Regulations 5 CCR
1002-41 and 42;
2. The source is identified in the SWMP;
3. BMPs are included in the SWMP; and
4. These discharges do not leave the site as surface runoff or to surface waters.
Dewatered groundwater shall be pumped or diverted to a sediment control BMP prior to discharge to the
ground. Locations of groundwater dewatering, as well as any BMPs utilized, will be noted on the Site Plans as
soon as such dewatering occurs. Additional information on groundwater dewatering is provided in the BMP
Manual, discussed in Section 3.3.
3.2.5.2 Stormwater Dewatering
The discharge of pumped stormwater (not including groundwater or other non-stormwater sources) from
excavations, ponds, depressions, etc., to surface water, or to a municipal separate storm -sewer system is
allowed by the Stormwater Construction Permit, as long as the dewatering activity and associated BMPs are
identified in the SWMP (including location of the activity), and BMPs are implemented in accordance with the
BMP Manual, discussed in Section 3.3 (CDPHE, 2007c).
Stormwater that collects in open depressions or trenches during constrtctio s will be dewatered into
an existing sediment control, such as a detention pond, a sediment trap, or,, im a well -vegetated area to
percolate into the ground and catch suspended sediment. The quality, source, an location of dewatering, as
well as any BMPs utilized, will be noted on the Site Plans as soon as such dewatering occurs. Additional
information on stormwater dewatering is provided in the BMP Manual, discussed in Section 3.3.
3.2.5.3 Pipeline Dewatering
New Department of Transportation (DOT) pipelines are hydrostatically tested with water upon completion of
construction. Once the hydrostatic testing has been completed, dewatering of the pipeline must occur. This
will involve the insertion of a displacer, commonly referred to as a pig, in the pipeline. The discharge rate will
be regulated, and energy dissipation devices, and/or sediment controls will be used, as necessary, to prevent
erosion, streambed scour, suspension of sediments, or excessive streamflow. Locations on pipeline
dewatering, as well as any BMPs utilized, will be noted on the Site Plans as soon as such dewatering occurs.
Additional information on stormwater dewatering is provided in the BMP Manual, discussed in Section 3.3.
3.3 Stormwater Vulikof BMPs
A Stormwater Manual of Best Anagement Practices (BMP Manual) is provided as Appendix E. The BMP
Manual has been prepared to provide EnCana personnel, contractors, and subcontractors with information on
the proper selection, design, installation, and maintenance of BMPs to manage oil and gas related stormwater
and to meet federal and state SWMP implementation requirements. The main objectives of the BMP manual
are to:
• Serve as an easy-to-use guide for selecting, designing, installing, and maintaining BMPs.
• Function as a reference for construction plans and specifications.
• Ultimately lead to the avoidance of any net increase in off-site erosion and sedimentation of waters of
the U.S.
The BMPs within this BMP Manual are organized into four main types of controls for easy reference: Erosion
Controls, Runoff Controls, Sediment Controls, and Non-stormwater Controls. Each of these types of controls
has been discussed earlier in this section of the SWMP.
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3.4 Phased BMP Implementation
Various BMPs will be implemented and maintained during different phases of the project. A description of
each phase is as follows:
• Preconstruction. The preconstruction phase involves the installation of BMPs (temporary and/or
permanent) around each site perimeter and at discharge points (such as vegetation buffers (no
installation required for this BMP), slash, wattles, diversions, sediment basins and reservoirs, etc...).
• Construction. The construction phase involves the stripping and stockpiling of topsoil, the excavation
and backfill for access roads, pipelines, and well pads, and the installation of additional BMPs
(preferably permanent BMPs) to control erosion and sedimentation (such as tracking topsoil piles and
the installation of roadside channels, culverts, diversions, etc...).
• Interim Reclamation. The interim reclamation phase primarily involves seeding of all disturbed areas
not needed during operation of the well pads. However, this phase also involves the installation of any
additional permanent BMPs that may be needed, as well as the continued maintenance and
inspections of all BMPs until final stabilization occurs. Final stabilization occurs once all surfaces are
built on, paved or graveled, and/or a uniform stabilized vegetative cover with a density of 70 percent of
pre -disturbance levels has been established or when an equivalent permanent, physical erosion
reduction method has been employed. A further explanation of final stabilization is provided as
section 4 of this plan.
• Final Reclamation. For pipelines, this phase involves seeding of all disturbed areas, and the
installation of any additional permanent BMPs that may be needed, as well as the continued
maintenance and inspections of all BMPs until final stabilization occurs. For other areas (roads, well
pads, facilities, etc...), this phase (which may occur after termination of this permit and under the
coverage of a new construction permit) occurs when operation of the area is no longer necessary. In
these cases, this phase will include the installation of any additional BMPs required during facility
decommissioning as well as the spreading of any remaining topsoil, the application of seed, and the
inspection/maintenance of all BMPs until final stabilization occurs.
Temporary controls, such as silt fencing, may be used to control sediment and erosion during preconstruction
and construction activities. Permanent controls, such as diversions and sediment traps, may also be used
during the initial phases of the project. However, only permanent controls will be used during interim
reclamation and final stabilization. Temporary controls may be converted into permanent controls (such as
revegetating a diversion) if needed. The primary control used during interim and final stabilization will be
revegetation. Seeding will occur as soon as possible after disturbance of an area is complete. If the seeding
is not successful, the area will either be eseeded or other controls will be put in place until reseeding can
occur.
ir 0
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4.0 Interim Reclamation and Final Stabilization
As soon as practicable after construction activities have been completed in a disturbed area, interim (for well
pads, or other facilities) or final (for roads and pipelines) reclamation will be started to prevent further erosion
of soil from that area. This typically occurs immediately upon completion of earthwork activities. All disturbed
areas (except for the surface of dirt roads, those portions covered by pavement or a structure, and those areas
used during operation of a well) will be stabilized with permanent controls. The most common measure used
to achieve final stabilization is revegetation. Mulching, erosion control blankets, surfacing with gravel or slash,
and/or other methods may also be used. Structural controls (such as diversions, berms, and sediment traps)
may be revegetated and used as permanent measures to control pollutants in stormwater discharges that will
occur after construction operations have been completed. Appendix E includes detailed information on each
of the previously discussed BMPs. In addition, a revegetation manual is provided as Appendix B, which
provides guidance as to possible methods and materials needed to accomplish revegetation on differing site
conditions. The specific BMPs used at each site are shown on the Site Plans wh. kept with the Site
Specific Records (Volume 2 of the Master SWMP).
Final stabilization means that all ground surface disturbing ties at the site have been completed, and all
disturbed areas have been either built on, paved, or a uniform vegetative cover has been established with an
individual plant density of at least 70 percent of pre -disturbance levels, or equivalent permanent, physical
erosion reduction methods have been employed. For purposes of this permit, establishment of a vegetative
cover capable of providing erosion control equivalent to pre-existing conditions at the site will be considered
final stabilization. Areas developed as stabilized unpaved surfaces as needed for operation of the facility after
interim reclamation, will also qualify as "finally stabilized." This includes dirt road surfaces and the portions of
the well pad surfaces that cannot be revegetated due to operational necessity, but does not include slopes,
ditches, and other areas where revegetation is necessary. Stabilized unpaved surfaces will be prepared in
such a way as to prevent ongoing erosion issues.
Coverage under the Stormwater Construction Permit may be inactivated for any individual site or a
portion/section of that site (i.e. the access road to a well pad) when the area has attained final stabilization and
all temporary erosion and sediment control measures associated with that area have been removed. An area
will be considered finally stabilized when construction and interim reclamation is complete and when the above
final stabilization criteria Ave been met, even though the site may be disturbed again in the future for final
reclamation. However, fu e land disturbances that follow final stabilization and result in disturbance of one
acre or greater (such as a lamation) will require new permit coverage at that time.
Upon final stabilization of any site i i °.n/section of a site, Oil and Gas Construction Field Permit
Certification NOTICE OF AMENDMENT OF PERMIT COVERAGE and/or Final Stabilization Certification
(provided in Appendix F) will be placed into the Site Specific Records binder to replace the Site Plans and the
inspection and maintenance records for that area. However, the Site Plans and inspection reports shall be
retained in a separate location for a period of three years following final stabilization of the Permit Coverage
Area. These documents will be made available to WQCD or EPA upon request and at the time of inspection.
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5.0 Inspection and Maintenance
Inspections and maintenance is an extremely important part of the Stormwater Construction Permit.
The Construction Manager will ensure that all stormwater management controls are constructed or applied in
accordance with governing specifications or good engineering practices. Experienced teams will be used for
construction. A first inspection will occur upon installation of the controls. In addition, all workers on the site
will be trained as to the location and use of the controls, especially those controls that will be disturbed as
construction proceeds across the site. The goal is to minimize the potential for inadvertent removal or
disturbance of BMPs and to prevent the off site transport of sediment and other pollutants.
5.1 Inspection Schedule
Inspections are required as soon as the first soil disturbance occurs at the site. Once final stabilization of the
site has occurred and the EnCana inspector has filled out the final stabilization certification sheet (see
Section 4), inspections are no longer necessary. Specific information regarding inspection schedules are
provided in the following sections.
5.1.1 Minimum Inspection Schedule for active sites
The minimum inspection schedule applies to those sites under active construction, which includes the period
from when the ground is initially disturbed to when construction activity is completed, and also includes the
preparation of areas that will be revegetated for interim reclamation. During the Active Site period, a thorough
inspection of the site stormwater management system (which includes all utilized BMPs) must be conducted at
least every 14 calendar days. Also, post -storm event inspections must be conducted within 24 hours after the
end of any precipitation or snowmelt event that causes surface erosion.
There are three exceptions to the minimum in'pection schedule which are described in detail within the next
three sections: post -storm event inspectiogs at temporarily idle sites (inspections required within 72 hours after
a storm), inspections at corlreted sites (inspections required monthly), and inspections during certain winter
conditions (inspections may not be required). Any use of an exception is temporary, and does not eliminate
the requirement to perform routine maintenance due to the effects of a storm event or other conditions that
may impact BMP performance, including maintaining vehicle tracking controls and removing sediment from
impervious areas. Inspections, as described above, are required at all other times.
5.1.2 Post -Storm Event Inspections at Temporarily Idle Sites
Temporarily idle sites are those where there are no construction activities occurring following a storm event.
At such sites, post -storm event inspections must be conducted prior to restarting construction activities at the
site, but no later than 72 hours following the storm event, and the delay noted in the inspection report. Routine
inspections still must be conducted at least every 14 calendar days.
5.1.3 Completed Sites
Once construction is completed and the site has been prepared for interim or final stabilization (including
completion of appropriate soil preparation, amendments and stabilization practices), the site (or portion of the
site) is considered a Completed Site (for purposes of the stormwater permit). Note: only construction activities
that result in a disturbance of the ground surface must be completed. Construction activities that can be
conducted without disturbance of the ground surface, such as certain well completion activities, would not
prohibit a site from otherwise qualifying as a Completed Site. (Completed Sites still require permit coverage
until the final stabilization criteria have been met)
Completed Sites qualify for a reduced inspection schedule, as the potential for pollution is reduced if the site
has been adequately prepared and/or seeded. However, because slopes and other disturbed areas may not
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be fully vegetated, erosion in these areas still occurs which requires maintenance activities such as regrading
and seeding of problem areas. As such, inspections must continue in order to address these situations.
During the Completed Site period, a thorough inspection of the site stormwater management system (which
included all utilized BMPs) is required at least once every month. The SWMP must be amended to indicate
those areas that will be inspected at this reduced frequency.
5.1.4 Winter Conditions Inspections Exclusion
Inspections are not required at sites where construction activities are temporarily halted, snow cover exists
over the entire site for an extended period, and melting conditions posing a risk of soil erosion do not exist.
This temporary exclusion is applicable only during the period where melting conditions do not exist, and
applies to the routine 14 -day and monthly inspections, as well as the post -storm -event inspections. It is typical
that when snow cover exists, even at a Completed Site, significant potential for erosion and BMP failure exists
when melting does finally occur. Therefore, the site should prepared prior to snow cover to ensure it is as
stabilized as possible, and be prepared to perform site maintenance when melt -off occurs, to alleviate any
potential problems. Inspection records (see Section 5.4) will document that winter conditions exist and that
inspections will be excluded.
5.2 Performing Inspections
Inspections will be conducted by qualified personnel on the followinQars:
• All vegetated areas until 70% of pre -disturbance vegetation legs A reac. .
• All BMP measures identified in this document.
• Construction site perimeter and discharge points.
• All disturbed areas.
• Areas used for storage of material/waste that are exposed to precipitation.
• Other areas determined to have a significant potential for stormwater pollution, such as demolition
areas or concrete washout locations, or locations where vehicles enter or exit the site.
These areas will be inspected to determine if there is evidence of, or the potential for, pollutants leaving the
construction site boundaries, entering the stormwater drainage system, or discharging to state waters. All
BMPs will be evaluated to determine if they still meet the design and operational criteria in the SWMP and if
they continue to adequately control pollutants at the site. Any BMPs not operating in accordance with
Appendix E of this SWMP will be addressed as soon as possible, immediately in most cases, to minimize the
discharge of pollutants, rago the Site Specific Records will be updated.
5.3 Maintenance
Maintenance activities will ensure that all control measures are functioning at optimum levels and that all
procedures and techniques will be in proper working order during a runoff event or spill condition. Any
maintenance, repairs, or replacements deemed necessary after required inspections will be corrected as soon
as possible (if not immediately), to minimize the discharge of pollutants. Certain maintenance procedures may
take a short period of time to make sure that all the proper safety precautions are in place, such as a "one call"
for utilities, if the maintenance involves excavation of sediment located above a buried pipeline.
Maintenance will include, but is not limited to:
• Pickup or otherwise prevention of litter, construction debris, and construction chemicals from
becoming a pollutant source prior to anticipated storm events.
• Removal of sediment from silt fences, sediment traps, and other sediment controls.
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• Reseeding of any bare spots where vegetation has failed to establish.
• Repairs and/or adjustments to any erosion and sediment control that is deteriorating or found to be
performing inadequately.
Detailed maintenance requirements for each BMP are identified in Appendix E.
When maintenance is required, the following process will typically be followed:
1. Perform inspections according to the minimum inspection schedule discussed in Section 5.1.
2. Note the need for maintenance on the inspection and maintenance report form.
3. If necessary, collect the additional materials and/or resources needed to perform the maintenance
activity.
4. Perform maintenance and note the date performed on the inspection and maintenance report form.
5. Re -inspect the area to ensure compliance.
5.4 Documenting Inspections and Maintenance
The permittee must document inspection results, maintenance activities, and maintain a record of the results
for a period of 3 years following expiration or inactivation of permit coverage. A typical inspection and
maintenance report form is provided in Appendix G. Although the site may have a phased construction
schedule, all construction areas may be inspected at the same time and on one form. Each well pad, road,
pipeline, or other facility which is inspected shall be clearly written on the inspection form. Inspection reports
will include the following:
• Date of inspection, name of inspector, and title of inspector ,%
• The area inspected (Site ID), type of area (well pad, acces9road, pipeline, etc.), phase of construction
(preconstruction, construction, etc.), and type of inspection (active, completed, etc.)
• Site specific information including disturbed area, soil type(s), ecosystem/vegetation type(s), receiving
waters, etc.
• Vegetation observations including the percent pre -disturbance vegetation and whether or not
vegetation growth has reached 70% of pre -disturbance levels
• Specific inspection requirements (all BMPs and areas of potential pollutant sources)
• Observed conditions including:
Location(s) of discharges of sediment or other pollutants from the site
— Location(s) of BMPs that need to be maintained
Location(s) of BMPs that failed to operate as designed or proved inadequate for a particular
location
— Location(s) where additional BMPs are needed that were not in place at the time of inspection
• Description and date(s) of corrective action(s) taken, and measures taken to prevent future violations
• Changes necessary to the SWMP
A hand drawn Site Plan shall be included, if necessary, to show the location(s) of any observed condition (as
listed above).
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After adequate corrective action(s) has been taken and recorded, or where a report does not identify any
incidents requiring corrective action, the report will contain a signed statement indicating the site is in
compliance with the permit to the best of the signer's knowledge and belief.
All completed inspection and maintenance report forms (a blank copy of which is included in Appendix G) are
kept with the Site Specific Records (Volume 2 of the Master SWMP).
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6.0 Plan Revisions and Retention
When BMPs or site conditions change, the Master SWMP (Volume 1) and/or the Site Specific Records
(Volume 2) will be amended to accurately reflect the actual field conditions. Examples include, but are not
limited to, removal of BMPs, identification of new potential pollutant sources, addition of BMPs, modification of
BMP installation/implementation specifications or maintenance procedures, and changes in items included in
the Site Plans. Changes to the Master SWMP (Volume 1) shall be noted on the SWMP Revisions log at the
front of this plan. Changes to individual site conditions will be noted in the Site Specific Records (Volume 2) on
the applicable inspection and maintenance report form. All changes in Volume 1 and Volume 2 shall be made
prior to actual changes in the site conditions, except for responsive SWMP changes, which shall be made
immediately after changes are made in the field or as soon as practical, but in no case more than 72 hours
after the change(s) in BMP installation and/or implementation occur at the site that require development of
materials to modify the SWMP. At a minimum, the Master SWMP will be updated annually.
The Master SWMP and the Site Specific Records will be retained at the EnCana field office in Parachute
during active construction and site inspections to ensure accurate implementation and maintenance of BMPs,
and required revisions. These documents will be retained for a period of three years following final
stabilization of the Permit Coverage Area. These reports will be made available to WQCD or EPA upon
request and at the time of inspection.
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7.0 Inactivation Notice
When all disturbed areas associated with the Stormwater Construction Permit have reached "final stabilization"
(as described in Section 4), all temporary erosion and sediment control measures have been removed, and all
components of the SWMP are complete, the area no longer requires coverage under the permit terms. At that
time, EnCana will submit an Inactivation Notice that closes this permit to the WQCD upon final stabilization of
all areas covered by the permit. A blank copy of this form is included in Appendix H of this document.
Upon receipt of the Inactivation Notice, the WQCD will provide written confirmation that coverage under this
permit has been terminated. This historical documentation will be maintained at the EnCana field office in
Parachute for a period of at least three years following termination of permit coverage.
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8.0 Signature
The signature page will not be signed unless the SWMP is requested by an agency as a legal document. At
that time, the supervisor will review the most updated version of the SWMP and sign it before submitting to an
agency.
"I certify under penalty of law that this document and all attachments were prepared under my direction or
supervision in accordance with a system designed to assure that qualified personnel properly gathered and
evaluated the information submitted. Based on my inquiry of the person or persons who manage the system,
or those persons directly responsible for gathering the information, the information submitted, to the best of my
knowledge and belief, is true, accurate, and complete. 1 am aware that there are significant penalties for
submitting false information, including the possibility of fine and imprisonment or knowing violations."
Printed name Ti
Signature
Printed name
Signature e
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9.0 References
CDPHE, 2007a. CDPS General Permit, Authorization to Discharge under the Colorado Discharge Permit
System. Colorado Department of Public Health and Environment. Water Quality Control Division.
Issued May 31, 2007.
http://www.cdphe.state.co.us/wq/PermitsUnit/stormwater/SWConstructionPermit.pdf
CDPHE, 2007b. General Permit Application and Stormwater Management Plan Preparation Guidance.
Colorado Department of Public Health and Environment. Water Quality Control Division. Revised
July, 2007. http://www.cdphe.state.co.us/wq/PermitsUnit/stormwater/SWConstructionApplication.pdf
CDPHE, 2007c. Rationale. Colorado Department of Public Health and Environment. Water Quality Control
Division. 2007.
http://www.cdphe.state.co.us/wq/PermitsUnit/stormwater/SWConstructionRationale.pdf
CDPHE, 2007d. Stormwater Fact Sheet — Construction at Qil nd Gas Facilities. Colorado Department of
Public Health and Environment. Water Quality Control Division. Revised July, 2007.
http://www.cdphe.state.co.us/wq/PermitsUnit/stormwater/OGfactsheet. pdf
George, R.D. 1927. Geology and Natural Resources of Colorado. University of C ado, Boulder, CO.
Mute!, C.F., and Emerick, J.C., 1992. From Grassland to Glacier - The Natura istory of Colorado and the
Surrounding Region. 40
U.S. Department of Interior, Bureau of Land Management. 2004. Environmental Assessment of the Grass
Mesa Geographic Area Plan. EA# 00140-2004-081 EA. Glenwood Springs Energy Office, Colorado.
Online version available at:
http://www.blm.qov/co/st/en/fo/gsfo/GSFO MasterPlansOfDevelopment.print.html
U.S. Department of Interior, Bureau of Land Management. 2005. Environmental Assessment of the Gant
Gulch Geographic Area Plan. EA# C0140-2005-134EA. Glenwood Springs Energy Office, Colorado.
Online version available at:
http://www.blm.qov/co/st/en/fo/gsfo/GSFO MasterPlansOfDevelopment.print.html
USEPA, 1990. NPDES Stormwater Regulations, 40 CFR Parts 122.26. U.S. Environmental Protection
Agency.
Weiner, R.J., J.D. Haun. 1960. Guide to the Geology of Colorado. Geological Society of America.
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Appendix A
General Permit Application
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STATE OF COLORADO
Bill Ritter, Jr., Governor
James B. Martin, Executive Director
Dedicated to protecting and improving the health and environment of the people of Colorado
4300 Cherry Creek Dr. S.
Denver, Colorado 80246-1530
Phone (303) 692-2000
TOD Line (303) 691-7700
Located in Glendale, Colorado
htlioliwww,cdphe.state.co.us
June 20, 2007
Laboratory Services Division
8100 Lowry Blvd.
Denver, Colorado 80230-6928
(303) 692-3090
Terry C. Gosney, Envir. Coord.
EnCana Oil & Gas (USA) Inc.,
2717 County Road 215 Ste. 100
Parachute, CO 81635
9701285-2687
RE: Final Permit, Colorado Discharge Permit System — Stormwater
Certification No: COR -034840
Mama Creek
Garfield County
Local Contact: Terry Gosney, Envir. Coordinator
970/309-8155
Dear Sir or Madam:
Colorado Department
of Public Health
and Environment
Enclosed please find a copy of the new permit and certification which have been re -issued to you
under the Colorado Water Quality Control Act.
Your old permit expires on June 30, 2007. This is a renewal to the permit, and replaces the old one.
See page 2 of the Rationale (the pages in italics) for a summary of the changes to the permit.
Your Certification under the permit requires that specific actions be performed at designated tunes.
You are legally obligated to comply with all terms and conditions of the permit.
Please read the permit and certification. If you have any questions please visit our website at :
www.cdphe.state.co.uslwq/perm_itsunitlstormwater or contact Matt Czahor at (303) 692-3517.
Sincerely,
r' �F
Kathryn Dolan
Stormwater Program Coordinator
Permits Unit
WATER QUALITY CONTROL DIVISION
xc: Regional Council of Governments
Local County Health Department
District Engineer, Technical Services, WQCD
Permit File
STATE OF COLORADO
COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT
WATER QUALITY CONTROL DIVISION
TELEPHONE: (303) 692-3500
CERTIFICATION TO DISCHARGE
UNDER
CDPS GENERAL PERMIT COR -030000
STORMWATER DISCHARGES ASSOCIATED WITH CONSTRUCTION
Certification Number C0R034840
This Certification to Discharge specifically authorizes:
EnCana Oil & Gas (USA) Inc.
LEGAL CONTACT:
Terry C GU.sney, L:ivir. C oord.
EnCana Oil & Gas (USA) Inc.
2717 Count' Road 215 Nie_ 100
Parachute, CO 81635
Phone # 970/285-2687
terry.gosney@encana.com
LOCAL CONTACT:
Terry Gosney, Envir. Coordinator,
Phone # 970/309-8155
ter rg ocneyaen Cana. cam
During the Construction Activity: Gas/Oil Field Exploration and/or
Development
to discharge stormwater from the facility identified as Mamm Creek
(44
which is located at:
Various locations
Various locations, Co 81 650
Latitude 39/25100, Longitude 107/50/00
In Garfield County
to: -- Colorado River
Anticipated Activity begins 07/01/2002 continuing through 06/30/2010
On 999 acres (999 acres disturbed)
Certification is effective: 07/01/2007 Certification Expires: 06/30/2012
Annual Fee: $245.00 (DO NOT PAY NOW — A prorated bill will be sent shortly.)
Page 1 of 22
Appendix B
Revegetation Manual
4*1Agil*
F:\Projects\014-2797\Documents\O pe rati on a l
Docs\SWMP\1. Mamm_Creek_SWMP_20101210.doc
Updated February 2008
EnCana Oil & Gas (USA), Inc. Revegetation Manual
Table of Contents
INTRODUCTION 2
1.0 Fertilization 2
2.0 Soil Preparation 2
2a. Disking 2
2b. Chisel Plowing 3
2c. Subsoiling 3
2d. Harrowing 3
2e. Cultipacking 3
3.0 Drill Seeding 3
3a. Equipment 3
3b. Methods of Use 4
4.0 Broadcast Seeding 5
5.0 Hydroseeding 6
6.0 Seed Planting Rates and Species Selection for Individual Seed Mixtures 6
7.0 Seed Quality 7
8.0 Seed Storage 7
9.0 Seeding Dates for the Raton Basin 8
10.0 Seed Germination 8
11.0 Seeding Success 8
12.0 Seed Mixtures for the Raton Basin 8
13.0 Mulching and Erosion Control 9
14.0 Maintenance of Seeded Areas 9
APPENDIX B: EQUIPMENT PHOTOS 10
Photo 1: Three Point Spreader 10
Photo 2: Fertilizer Buggy Wagon 10
Photo 3: Tandem Disk 11
Photo 4: Rhome Offset Construction Disk 11
Photo 5: Chisel Plow — Brillion 8' 12
Photo 6: Chisel Plow — John Deere 12
Photo 7: Subsoiler — John Deere 13
Photo 8: Spike Tooth Harrow 13
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Photo 9: Flex -tine Tooth Harrow 14
Photo 10: Spring Tooth Harrow 14
Photo 11: Cultipacker — Brillion 15
Photo 12: Truax Brand Drill Seeder 15
Photo 13: Horizon Brand Drill Seeder 16
Photo 14: Close-up of Double Disk Furrow Openers and Depth Bands 16
Photo 15: Press Wheels 17
Photo 16: Drag Chains in Transport Position 17
Photo 17: Trashy Seed Box Picker Wheels 18
Photo 18: Small Grain Standard Seed Box/Seed Cups 18
Photo 19: Seed Drill Gear Assembly 19
Photo 20: Seed Tubes 19
Photo 21: Hand Broadcast Seeder 20
Photo 22: Hydroseeder — 3000 Gallon Tank 20
Photo 23: Hydroseeder with Gun Operator 21
Photo 24: Seed Tag 21
EnCana Oil & Gas (USA), Inc. Revegetation Manual
Introduction
The objective of a revegetation program is to establish a diverse self sustaining vegetative
cover that provides for erosion control and a productive land use. There is not a single best
method to revegetation practices. This is why revegetation is considered "an Art and a
Science". As many revegetation practitioners have said in the past it is better to be lucky
than good. Meaning that the most critical ingredient needed to complete the cycle of
revegetation is adequate and timely rainfall. Achieving successful revegetation of a disturbed
area is even more complicated than a successful crop from dry land farming. Farming
practices are normally completed on land that has prime soil for plant growth and consist of
cereal grain crops that are easier to grow than native grasses.
This manual is for the layman who needs to understand revegetation as part of their job
duties with EnCana Oil & Gas (USA), Inc., but does not necessarily have the college degree
or hands on experience to complete this type of work. This manual will present steps and
options that will help increase the chances of successful revegetation. There are sections
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that outline methods and materials needed to accomplish revegetation on differing site
conditions.
1.0 Fertilization
Fertilization of areas to be revegetated is often times a consideration. Soil test of the areas to
be seeded are the best way to determine if fertilizer is needed. The major nutrients needed
by native vegetation for growth is Nitrogen, Phosphorus, and Potassium. Nitrogen is for top
growth of plants, Phosphorus is for root growth, and Potassium is for the overall health and
vigor of plants. All fertilizer will list the nutrients in the order of Nitrogen, Phosphorus, and
Potassium or N -P -K. For example a product listed as 18-46-0 will contain 18 % Nitrogen,
46% Phosphorus, and 0% Potassium.
Nitrogen may not be at desirable levels in the soil at the time of seeding. However, research
has shown that adding nitrogen at the time of seeding can often times increase the growth
and cover of weed species at the expense of the desirable seeded species. Also, nitrogen can
not be metabolized by native grasses until they are approximately one year old. For these
reasons, most experienced revegetation specialists will not recommend the use of nitrogen at
the time of seeding. Instead, they will tend to place nitrogen fixing legumes in the seed
mixture. These legumes will pull nitrogen from the atmosphere and provide it later to other
plants such as grasses.
Phosphorus most likely will be the limiting nutrient in the soil. It is advisable to add
phosphorus prior to soil tillage and work it into the soil to a depth of 6 to 8 inches.
Most native soils in Colorado contain optimum levels of potassium. Therefore, potassium
should very seldom if ever be needed in the Colorado Fields.
Fertilizer is typically applied using a Three Point Hitch Tractor Mounted Spreader or Fertilizer
Buggy Wagon Implement (See photo #'s 1 and 2: Three Point Spreader and Fertilizer
Buggy Wagon). Both of these styles of spreaders are considered broadcast spreaders. Their
width of application is typically between 10 and 30 feet. The amount of fertilizer applied per
acre is controlled by a slide gate opening on the bottom of the spreader.
2.0 Soil Preparation
Soil Preparation is a critical first step to revegetation. The objective is to have the surface 8
inches of soil loose enough to allow for root growth and firm enough on the surface for good
seed to soil contact. The soil surface should also be relatively free of rocks, debris, and dirt
clods greater than 3 inches in diameter. Too much debris, rock, and clods will prohibit proper
seed placement.
There are several types of implements that can be pulled behind farm tractors or small
dozers to till the soil. These consist of disk, chisel plows, subsoilers, and harrows. The
working widths commercially available for soil preparation implements typically vary 6 feet to
over 20 feet. The working width of implements used by contractors is typically based on site
access and size. Also, smaller contractors may have a limited number and size of tillage
implements in their equipment fleet.
2a. Disking
Disks are normally used where there is significant surface compaction and the soil needs to
be tilled to loosen and large soil clods need to be broken down. Disks also are used where
there is a concern of bringing more rock up to the soil surface as will occur with chisels,
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rippers, and subsoilers. Disks should not be used alone where extreme subsoil compaction
exist. There are offset disks and tandem disks available on the market. Tandem disks turn
the soil twice and offset disks move the soil in opposing directions and help level the surface
(See photo #'s 3 and 4: Tandem Disk and Rhome Offset Construction Disk). On very rough
sites a Rhome brand construction type disk is recommended because of the weight of the
disk and its ability to withstand rough conditions (See photo #4: Rhome Offset Construction
Disk). A heavy construction disk normally needs to be pulled behind a mid-size dozer or large
4WD tractor because of its weight and soil penetration ability.
2b. Chisel Plowing
A chisel plow cuts through the soil and helps to eliminate soil compaction to a depth of
approximately 8 inches (See photo #'s 5 and 6: Chisel Plow). Chisel plowing to a shallower
depth can help cut off and kill weeds. Some rock and clod material can be brought to the soil
surface during this operation. If a significant amount of clods are brought up to the soil
surface then a cultipacker (See Section 2e.) should be utilized to break clods back down prior
to seeding.
2c. Subsoiling
Subsoiling is used to break up compacted soil layers 6 to 24 inches in depth (See photo #7:
Subsoiler). Subsoiling helps to improve water infiltration and aerates subsoil layers to
encourage root penetration. Subsoiling can bring up significant large clods in zones with
heavy clays and compacted zones. Cultipacking (See Section 2e.) will need to follow
subsoiling when large volumes of clods greater than 3 inches are brought to the soil surface.
2d. Harrowing
Harrows lightly scratch the ground to loosen a shallow layer of soil (4 inches or shallower).
The three styles of harrows consist of a spike tooth harrow (See photo #8), flex -tine tooth
harrow (See photo #9), and spring tooth harrow (See photo #10). Harrows should only be
used on loose friable soils that do not require deep tillage. Harrows can be used to remove
undesirable vegetation such as weeds that will interfere with seeding operations. Harrows will
break up surface crust and generally break up clods of topsoil material, but not hard and
massive subsoil material. Harrows are excellent for preparing a seedbed for small seeds such
as forbs and some shrub seeds.
2e. Cultipacking
Cultipackers consist of front rollers that are an open mesh, a middle set of rippers, and a
back set of rollers with knurled edges (See photo #11: Cultipacker). The front set of rollers
crushes clods, the rippers bring additional clod material to the soil surface, and the rear roller
crushes remaining clods and firms the soil surface.
3.0 Drill Seeding
3a. Equipment
Drill seeders are implements that are towed behind an agricultural seeder or small crawler
dozer (See photo #'s 12 and 13: Truax and Horizon Brand Drills). Drill seeding is considered
the optimum means of planting grasses, forbs, and most shrub seed. Rangeland type drill
seeders used for planting native vegetation should have several critical features or
components. This includes three seed boxes, double disk furrow openers equipped with
depth bands, press wheels or drag chains (See photo #'s 14, 15, and 16: Close-up of Double
Disk Furrow Openers and Depth Bands, Press Wheels, and Drag Chains in Transport
Position).
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The drill seeder should be equipped with three different seed boxes: A legume box is
needed for small seed such as wildflowers, alfalfa, sweet clover, etc., a trashy seed box with
aggressive picker wheels for handling trashy seed such as bluestems and gramas (See photo
#17: Trashy Seed Box Picker Wheels), and a standard seed box used for flowable seeds
such as wheat grasses and small grains (See photo #18: Small Grain Standard Seed
Box/Seed Cups). Most native grass drill seeders come in 8 to 10 foot planting widths.
The seed drill is activated by a series of gears and chains that are attached to one of the drill
wheels on the drill (See photo #19: Seed Drill Gear Assembly). When the drive wheel is
activated it turns the gears which turn the shafts that run through the seed boxes. The seed
gravity feeds into seed cups that are attached to the shaft (See photo #18: Small Grain
Standard Seed Box/Seed Cups). The trashy seed box has an extra shaft that runs above the
seed cup shaft and has an aggressive picker spiral agitator wheel which forces the seed
down to the seed cup so it does not simply float in the seed box (See photo #17: Trashy
Seed Box Picker Wheels). The seed from all seed boxes falls through a hole in the seed box
where a flexible rubber tube is connected between the bottom of the seed box and the
double disk furrow openers (See photo #20: Seed Tubes). The double disk furrow openers,
as the name implies, opens a small trench in the soil that the seed falls into. As the drill
moves forward the seed is covered with soil and pressed into the ground by the press wheels
or drag chains (See photo #1s 15 and 16: Press Wheels and Drag Chains in Transport
Position). It is very important that the seed is planted to the right depth and the seed is
pressed into the soil firmly to press out air and allow the seed to absorb moisture as it
becomes available to help germinate the seed. The double disk is attached to a lift arm
assembly that allows it to roll and float over minor obstacles in the ground such as small
rocks tree branches, and dirt clods. The drill should be lifted up by using the hydraulic
cylinder when large rocks and debris are encountered in the drills path. While rangeland type
drill seeders are built to handle tough conditions they can be high maintenance and require a
supply of extra parts in the field when breakdowns occur.
3b. Methods of Use
Drill seeders should be calibrated for use on a small area before all seeding is completed.
Most manufacturers of drill seeding equipment can provide general guidelines as to the
amount of seed output by seed box for flowable seeds versus trashy seeds. Calibration will
help ensure that the proper amount of Pure Live Seed (PLS) is planted. PLS of any given
vegetation species is determined by a registered seed testing laboratory. Individual seeds
from individual species are normally placed in a growth chamber to determine the
percentage of seeds that will germinate, For example, if 100 seeds are placed in a growth
chamber and forced to germinate and only 90 germinate, the germination percentage is
considered 90%. Purity is the measure of viable seed and separates out inert material, weed
seed (not more than 1% according to federal regulations) and other crop seed. Therefore,
the total viable seed is the percent by count that will germinate. The following example
provides an illustration of a method of calculating an amount of seed to be planted which
takes into account the variation of seed germination and purity of the seed source:
Example of a Pure Live Seed (PLS) Calculation:
A recommended seed mixture requires that 5 lbs. (PLS) of intermediate wheatgrass
be planted:
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Intermediate wheatgrass germination = 80%
Intermediate wheatgrass purity = 90%
80% X 90% (PLS) = 0.72
5 lbs (PLS) to be planted
0.72 (PLS factor)
= Approximately 7 lbs of bagged
seed should be included in the
mixture so that 5 lbs of PLS will
be planted.
Thus, a seed species PLS factor is based on germination X purity. In order to plant one PLS
pound of a species you may end up planting 1.6 to 2.0 times more seed which is considered
the bulk seed amount.
The operator should first decide whether to have the seed mixture divided by trashy vs.
flowable species or to combine the species and utilize both seed boxes to achieve proper
seed output. It is best to consult with your seed dealer to determine just how trashy or fluffy
the seed will be. There are several different opinions in the industry as to how to calibrate a
native grass seed drill. The most elaborate method of calibration involves jacking up the drill
and spinning the drive wheel the number of revolutions that represent an acre. Seed is
caught from one of the seed tubes and weighed after spinning the gauge wheel and the seed
weight for one tube is converted into the fraction of an acre that the tube represents. Most
drill seeders contain either a slide bar with number settings or gear ratios with numbers to
increase or decrease the seed output. These adjustments should be made if more than a 10
% variance of less seed than required occurs. Also, adjustments should be made for too
much seed being put down which can be a costly mistake as well as planting too much seed
for what the soil and environment will support.
The simplest way to calibrate a seed drill is to place two acres worth of seed in the seed box
and drill seed 1/2 acre. Fill the seed box back up to the height it existed with two acres worth
of material. Next determine if you had to fill more than a 1/2 acre of material or less than, or
you were right on with the calibration. Be aware that if you had to place less seed back in the
box, than the volume you started with, you are not seeding enough. Calibration of a seed
drill can change overnight if seed is left in the drill. Seed may settle in the seed box causing a
slight amount of packing and humidity can change the way seed flows from the drill. It is
best to finish out the seed in the seed box by the end of the day and start fresh the next
day. Remember to check the calibration of the drill at least every 10 acres or each time you
refill the drill. Always keep the drill boxes full enough that the seed feeds properly.
Remember when seeding on side slopes that seed can slide to the down hill side of the seed
box leaving little or no seed to be planted on the high side of the drill. Most drills come
equipped with divider boxes to keep seed from sliding all the way to the low end of the drill.
If the seed drill does not have divider boxes think of ways to place sheet metal or even card
board in the drill to divide it into at least three different compartments.
All drill seeding should be completed parallel to slopes or on the slope contour. Drill seeding
up and down a slope can result in accelerating erosion after rainfall since the indentations
from the drill rows help to concentrate flow and accelerate soil movement down hill. Most
native grass species and forbs germinate best if seeded to a depth of 1/4 to 1/2 inch. Most
depth bands on drills are set at 1/2 inch so the seed can not be planted any deeper.
4.0 Broadcast Seeding
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Broadcast seeding is typically done where steep slopes prohibit safe operation of a farm
tractor or the soil surface is covered with large rock that cannot be economically removed.
Hand seeding may be needed in small, tight access areas where machinery cannot effectively
operate. Broadcast seeding can be performed either with a hand seeder (See photo #21:
Hand Broadcast Seeder) or tractor mounted spreader (See photo #1: Three Point Spreader).
Broadcast spreaders typically spread an even swath of seed onto the soil surface. Depending
on the roughness of the ground, the seed can end up at various depths in the soil. Broadcast
seeding by hand or machine alone will not typically provide good results unless the seed is
covered with soil. Broadcast seeding with a tractor should be followed by using a flex harrow
to cover the seed with soil. Hand broadcast seeding should be followed by hand raking with a
hard tine rake. In both cases the seed should not be raked deeper than 1/2 inch into the
ground.
5.0 Hydroseeding
Hydroseeding is completed with an actual hydroseeder machine. Most people in the industry
use the term hydroseeder/hydromulcher interchangeably since they do both operations (See
photo #22: Hydroseeder — 3000 Gallon Tank). A hydroseeder/hydromulcher machine consists
of a water tank equipped with a motor that operates a hydraulic agitation system. The top of
the machine contains a turret or gun where the seed is discharged (See photo #23:
Hydroseeder with Gun Operator). The operator will mix the seed and a small amount of
hydromulch in the tanker. The green dyed hydromulch will help the operator see the sprayed
area during the seeding operation. The objective of using the hydraulic pressure of the
machine is to use enough force from the engine RPM's to shoot or push the seed into the
ground. If the seed is not adequately covered with soil, hand raking of the area or slope
harrowing should be employed.
6.0 Seed Planting Rates and Species Selection for Individual Seed Mixtures
Establishing seed mixtures and planting rates for different native grass, forbs, and shrub
seeds is normally done by a revegetation specialist, soil scientist, plant ecologist, or
agronomist. These professionals have several years of experience in knowing how many
pounds of each type of seed are needed to increase the chances of revegetation success.
Any expert in the revegetation industry knows that there are no absolutes in designing a
seed mixture. Designing a seed mixture combines both an "Art and a Science".
The consultant takes into account what vegetation species are currently growing by
vegetation zone on the site. A native vegetation zone or community is controlled by several
environmental factors including elevation, degree of slope, aspect of slope (East, west, north,
or south facing), soil type (for example sandy or clayey), and the amount of precipitation that
the area receives each year. Vegetation communities will typically have at least two grass
species to as many as eight species. Shrub and forbs species will also typically be present.
There should be at least three grass species in a revegetation seed mixture. Having a
number of species in the mixture will promote diversity in the final vegetative cover and will
reduce the risk of revegetation failure if one or more of the species does not adapt to site
conditions.
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Typically a consultant will base the poundage of each species on several factors. Some
species are hard to establish and may require higher poundage of seed to have a chance to
establish. Some species may be easy to establish and are seeded at a higher rate to ensure
some initial vegetation cover after seeding. Some vegetation species are very aggressive and
should represent a small percentage of the seed mixture or they will dominate the site. Each
vegetation species has a different number of seeds per pound. For example, Western Wheat
Grass has approximately 110,000 seeds per pound while Blue Grama has 825,000 seeds per
pound. There are different opinions with scientist as to how much seed to plant on an acre or
square foot basis. Typically, the number of seeds planted per square foot is a consideration.
Chenoweth & Associates believes that 30 to 75 seeds per square foot should be planted on
any site. Others believe that 144 seeds per square foot should be planted on any site,
especially steeper windblown slopes. The higher number of seeds per square foot could be
based on the risk of loosing seed to water erosion on steep hill sides or wind erosion in high
wind prone areas. Higher seeding rates could also be based on very good topsoil
replacement that will allow a site to support more vegetation.
The general role of thumb for hydroseeding and broadcast seeding is to double the drill seed
rate of seed. This rule was established since broadcast and hydroseeding does not typically
provide for optimum seed placement and planting depth as compared to drill seeding.
A seed mixture at a minimum will consist of native grasses and forbs. As previously
mentioned at least three grass species should be in any revegetation seed mixture. The
operator (such as EnCana), landowner (either private landowner or federal agencies such as
the Forest Service or BLM), and Revegetation Specialist typically consult with one another to
determine what the seed mixture should contain. These individuals or organization will
determine if the seed mixture should contain only grasses or whether shrub and forbs seed
should be added to the seed mixture as well. Typically cost of seed is a driving factor on
deciding if these species are added to a seed mixture.
7.0 Seed Quality
Seed purchased from a reputable seed dealer should contain a seed tag that provides the
germination and purity of each species in the bag. The seed tag should also indicate the Lot
number of the seed (See photo #24: Seed Tag). The lot number is to document where and
when the seed was harvested. The seed supplier should supply seed that has been tested
within one year of the purchase date.
8.0 Seed Storage
Seed should be properly stored until it is used. Seed should be kept in a cool dark
environment. The temperature in the storage area should never exceed 85°F for enclosed
containers and 90°F for good ventilated storage. Seed is not typically impacted by freezing
temperatures and in fact some seeds benefit from cold and heat scarification in order to
germinate. Seed which becomes wet for any period of time exceeding 48 hours should not be
used. If seed is stored over winter or for any extended period of time should be retested.
Some seed species will decrease in germination percentage faster than others. Additional
seed of some species may have to be purchased and reblended into the original seed mixture
to bring the mixture back up to the proper PLS rate desired.
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9.0 Seeding Dates for Colorado Oil & Gas Fields
Desirable seeding dates are typically tied to periods when precipitation will closely follow the
actual seed planting. Moisture in the Colorado oil & gas fields typically comes during the
summer monsoon period which occurs in July and winter rain or snow which is highest in
January, February and March. Seeding needs to be completed when the soil is not frozen or
wet. Therefore, consultants feel that optimum seeding dates are early in the spring until May
1, mid-July until September 1, and after the first heavy frost until permanent ground freeze.
These dates do not always coincide with construction schedules and the urgency to seed
after earth work is completed to help control erosion. There are times that seeding a cover
crop during a poor seeding period may be beneficial. There are several sterile hybrid seeds
on the market today that germinate easily as long as there is some degree of soil moisture
available. They are considered sterile since they will not reseed themselves. These hybrids
are called treticale. They are typically a cross between winter wheat and a wheatgrass.
10.0 Seed Germination
Depending on the vegetation species, germination can occur as soon as 10 days after
seeding. Germination is dependent on adequate soil moisture and soil temperature. Normally
grass seed needs at least 54°F surface soil temperature to germinate. These temperatures
should exist from late April until late August in the Colorado oil & gas fields depending on
elevation and soil shading. Germination of all species can often times take several days or
weeks depending on the number of species in the seed mixture. Again, this assumes there is
adequate soil moisture in addition to proper soil temperatures for seed germination. At the
time of peak germination flush as many as 10 to 20 seedlings per square foot may be
present. Approximately 75% of the seedlings die off shortly after germination as the plants
reach equilibrium of what the soils moisture and nutrient levels will support. If hot dry
periods follow germination, some or all of the grasses and forbs may die. A further discussion
of this situation is provided in the following section.
11.0 Seeding Success
After germination occurs, new seedlings are very dependent on continued available soil
moisture to survive. Some grass species are more susceptible to desiccation and die back
than others. Thus, if adequate and timely precipitation does not occur during the first
growing season failure of the revegetation may occur. This is why it is very important to use
the proper materials and procedures identified throughout this report.
There are at least two university research units that agree on determining revegetation
success after the first growing season. Typically, 3 to 4 live healthy seedlings per square foot
after the first growing season will yield long term revegetation success. These seedlings will
ultimately yield approximately 40% to 60% canopy cover after the plants mature.
12.0 Seed Mixtures for the Colorado Oil & Gas Fields
Seed mixtures will have to be prepared for use in the Colorado oil & gas fields of EnCana Oil
& Gas (USA), Inc. well pads, road cut and fill slopes, pipelines and borrow pits. These seed
mixtures will be site specific to the ecosystems present. See Appendix A — Seed Mixture
Charts with geographic photos for the seven zones of the Colorado oil & gas fields.
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13.0 Mulching and Erosion Control
Conserving soil moisture and controlling surface erosion are very important during seedling
establishment. Lack of proper erosion control can result in seed being washed away before it
germinates. Mulch materials can help conserve soil moisture and reduce erosion. Mulch
materials also provide other beneficial functions. They include increasing moisture infiltration
from rain and snow, cooling the soil surface, and providing valuable soil organic matter to
increase soil structure.
Several different types of mulch materials can be used for revegetation purposes. The most
common ones used are hay/straw mulch, hydromulch, Flexible Growth Medium and Bonded
Fiber Matrix. There are also several types of roll out erosion control blankets that are
available to be used in place of mulches on steep slope areas, drainage areas, and stream
channels.
Erosion control is now required by federal and state laws on most disturbed construction
sites and falls under what is called Storm Water Management Permitting. A separate report
was prepared for EnCana Oil & Gas (USA), Inc. dealing with education on Storm Water
Management Planning and Permitting. An extensive list of mulching and erosion control
products is discussed in this report.
14.0 Maintenance of Seeded Areas
Maintenance of seeded areas includes weed control, erosion control, and touch up seeding.
Most newly seeded sites require these maintenance operations during the first growing
season to help insure successful revegetation. In general weed control should be employed
anytime weed cover exceeds 20% canopy cover. Site specifics will vary; sometimes 20%
weed canopy cover may be desirable. Mechanical weed control must be used immediately
after seeding is completed and most likely until the second growing season. Mechanical weed
control consists of mowing or hand pulling weeds. Herbicide applications will kill new
seedlings and seed in the ground. Herbicides can only be used after the vegetation becomes
established at mature height. Reseeding or touch up seeding should occur after adequate
time for germination and when bare spots greater than 10 square feet exist. A more
extensive discussion of maintenance of seeded areas and weed control can be found in Oil &
Gas Field Specific Revegetation Plans.
APPENDIX A: SEED MIXTURE CHARTS WITH GEOGRAPHIC PHOTOS
APPENDIX A: SEED MIXTURE CHARTS WITH GEOGRAPHIC PHOTOS
Seed Mixture # 1 = to be developed per field area
Seed Mixture # 2 = to be developed per field area
Seed Mixture # 3 = to be developed per field area
Seed Mixture # 4 = to be developed per field area
Seed Mixture # 5 = to be developed per field area
Seed Mixture # 6 = to be developed per field area
Seed Mixture # 7 = to be developed per field area
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APPENDIX B: EQUIPMENT PHOTOS
Photo 1: Three Point Spreader
Photo 2: Fertilizer Buggy Wagon
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Photo 3: Tandem Disk
Photo 4: Rhome Offset Construction Disk
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Photo 5: Chisel Plow — Brillion 8'
Photo 6: Chisel Plow — John Deere
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Photo 7: Subsoiler — John Deere
Photo 8: Spike Tooth Harrow
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Photo 9: Flex -tine Tooth Harrow
Photo 10: Spring Tooth Harrow
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Photo 11: Cultipacker — Brillion
Photo 12: Truax Brand Drill Seeder
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Photo 13: Horizon Brand Drill Seeder
Photo 14: Close-up of Double Disk Furrow Openers and Depth Bands
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Photo 15: Press Wheels
Photo 16: Drag Chains in Transport Position
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Photo 17: Trashy Seed Box Picker Wheels
Photo 18: Small Grain Standard Seed Box/Seed Cups
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Photo 19: Seed Drill Gear Assembly
Photo 20: Seed Tubes
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Photo 21: Hand Broadcast Seeder
Photo 22: Hydroseeder — 3000 Gallon Tank
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20
Photo 23: Hydroseeder with Gun Operator
Photo 24: Seed Tag
Kind: EnCana Table 1-3 Shrobland Grasses Pad 1-27
Int 21994AR
Mixture;Variety:
Thick$pike Wheatgras5e OritanA
Ellmobunch Wheatgrass, Socar
Slender Wheatgrao*, SAO Lui
Canby Dioegraus, Oanbar
Prairie Junegraus!
Pure', Gr' Origin
30.65 87 WA
30.54 05 WA
28.14 92 WA
5.54 85 CAN
0.9a 87 WA
Crop: 0.S7'. 'pert.: 3.34' Weed's: 0.32% Not Wgt: 25.6.4
TE$T DATE:2-07 NOXIOUS 'ArEEDS: NOME FOUND
EMARKS: ito'cky Mt. Environmental Concern
.51/ ---dov-evrr-1—a-EPe- broa-dra- a e, ac es
rill rate
Seal -1333 Hwy fir) 1.,)nmorit, "011I5I:J
EnCana Oil & Gas (USA), Inc Chenoweth & Associates Environmental Consultants
21
Appendix C
Existing Soil and Vegetation Data li
F:\Projects\014-2797\Documents\O pe rati on a l
Docs\SWMP\1. Mamm_Creek_SWMP_20101210.doc
Updated February 2008
Figure 1. Mamm Creek
Soil Types
Mamm Creek Unit Soils
MAP SYMBOL, SOIL NAME
12, Bucklon-Inchau loams
16, Cimarron loam
17, Cochetopa loam
24, Dollard -Rock outcrop, shale, complex
28, Heldt clay loam
29, Heldt clay loam
3, Arvada loam
30, Heldt clay loam
31, Heldt clay loam
32, Holderness Variant clay loam
33, Ildefonso stony loam
34, Ildefonso stony loam
39, Jerry loam
4, Arvada loam
40, Kim loam
41, Kim loam
42, Lamphier loam
44, Morval loam
45, Morval-Tridell complex
46, Nihill channery loam
5, Ascalon fine sandy loam
50, Olney loam
51, Olney loam
54, Potts loam
55, Potts loam
56, Potts loam
58, Potts-Ildefonso complex
6, Ascalon fine sandy loam
65, Torrifluvents
66, Torriorthents-Camborthids-Rock outcrop complex
67, Torriorthents--Rock outcrop complex
68, Vale silt loam
69, Vale silt loam
7, Ascalon -Pena complex
70, Vale silt loam
71, Villa Grove -Zoltay loams
9, Badland
•RA1
I
•
•143.144
1-24
1- �6R11
018
•
F28
•
K28NW
•
H21
4i
121421
K22NW
•J22W
•B27
D27NW
•
•K27NW
•M27NW
027NW
A33NWC34NW
G33NW •
•
K33NW
H27NW
•B34NW
•H34N W
34NW
P33BW
N33 SP33• •
K� 33NWM34NW
�K4B
•B9W
•C9W
E9• F9
K8W
•
N29
No Soil Data
Available
M3
:M3A
N9B •19W
.N9W
•B16W
•C28
J16W
•
F10
•
D151/41i5
• C15B
13+13
H23NW
•J23NW •
P238 P23
C26N W
•
A19N 0
H24NW
K24M•J24 K19CNEBNE
KRONE
•
C3ONE
MCEF G25NW •B3ONE
• H26NW •F25
• 126NW J25
J26NW •KA
••J26NWB
P2do..6B P26
C35 PABX
• •B35W
H1035
H356
L35 K35NW 135
•
H3
6N W
• •K3A36 H367
6
•p@p35 N36
LB1:6NW
J2W 12iWW
CSR2-15•RR2-w
• N16
•N1
A10B
• A10 CSR11-6 8118WD126D12
RUMBA�
•
E 3- 1 $ W •
•N25
B36X•36
•CCS
N3ONE
•P36
:1W
HMWT
•P1
•
HMC:C7E
C29NE B29NE
• •A29NE
•K29NE
30NE : 29
B31 D3`2D32
• D32WF3•RBWF
•328 32
f�32W
3jK32
L J32
•
•M32 N32 • +P32
•
•J6 •16 •L5 •J5^ UNNS-9
•
K31 J31
N31
•
•B33N E D34N E
•
E33NE
•` F33
G333NE L34
• P6
N5AN5 • M4E
FED5-1e
87 KRK7-1 DS COUEY8-3
• • • wCOUEY8-1
F12 KRK7-7H7 •
J11�11W SJ12•FFERK�� J• KRK7-9 •CHRISTNJ8ER8-6
11p8 110 ••• P11 • • KRIA-�B •COU9'411
X108 PARK11•4 012 •PKiK7-1 �O7WO�P7E• •N8E
•4W814W D13WD13 • A113:A13 �840:
__
• •E G13W •F1S
•LI5W
115a115W
H15
•G22
N22W
•
A22W
•
G14W
• 113 J18
•J14•J1341°
•
P13B •
•N18
P14N13WjN13 • P13
62, •
M23WN23W
K27
• 0127W F26W
L15SW
•
•
aF24 W
S
H23W
•
P27W P26W
N26W •
C2SW
D2 � M24W
•B25
L25W
1
H2SW
•
K2SW I2SW
•
•M2S W
P11SW
K19E.F19 G19
719E •
• •
K4E
P33N433
•M34NE
L3E
• •
P4E
•
• N4E
C9E
• •
•L9
017E M MR17-1
• • •C17AE
E16
1 • • H17E •
•
X18 L17E MMR17-9
••K17E•
•H1 :E20E
•019E
29E
•
630E
•
•J25W
•C36W
•G1SW
P306
•
•C31E
•H31
•K31 E
031E
•
•H6
J6SE
••
•N7
•COUEY17-12A
•
ii/1MRT45
MMRT45-20P
•G32E
HSSE
•
•
FOE
•J9E
•B16E
•C21
•K28E
K16SE
•
1
M15
N3E
•
•FLOE
E22E
•
E27E
•
DOSE
•
M1OSE
•
•P34NE
115SE
A15
•
102
•M1E 4101E
•H23
M24E
D26
• •B26E
•K26E
C2•
•G11SE
•N12E
•B25E
B1SE
•
•P1SE
.4
Reference: Soil Survey Staff, Natural Resources, Conservation Service, United States Department of Agriculture.
Web Soil Survey. Available online at http://websoilsurvey.nrcs.usda.gov/accessed [02/01/2008]
APPENDIX C
Soils Table - Mamm Creek Unit SWMP
Page 1 of 6
Map Unit Number -
Soil Name
Surface
Runoff (slow/
medium/
rapid)
Erosion Potential
(slight/
moderate/
severe)
Soil Description
Soil
Depth
-
USDA Texture(s)
m
Unified
Classification
Permeability
(inch/hour)
Available
Water Capacity
(inch/inch)
Organic
Matter
(%)
R3 -Arvada loam, 1 to 6%
slope
medium
moderate
Deep, well drained, sloping soil on fans and high terraces.
0-3
Loam
CL -ML
0.60-2.00
0.16-0.18
0.5-1
3-17
Clay, Silty clay loam
CL, CH
0.06-0.20
0.07-0.09
17-60
Clay loam, Silty clay loam
CL
0.06-0.20
0.09-0.11
R4 -Arvada loam, 6 to
20% slope
moderate/rapid
severe
Deep, well drained, sloping soil on fans and high terraces.
0-3
Loam
CL -ML
0.60-2.00
0.16-0.18
0.5-1
3-17
Clay, Silty clay loam
CL, CH
0.06-0.20
0.07-0.09
17-60
Clay loam, Silty clay loam
CL
0.06-0.20
0.09-0.11
R5 -Ascalon fine sandy
loam, 1 to 6% slope
medium
moderate
Deep, well drained, nearly level to gently sloping soil on mesas,
alluvial fans, and terraces.
0-5
Fine sandy loam
SM
0.60-6.00
0.11-0.16
1-3
5-30
Sandy clay loam
SC, CL
0.60-2.00
0.13-0.15
30-60
Sandy clay loam
SC, CL
0.60-6.00
0.11-0.15
R6 -Ascalon fine sandy
loam 6 to 12% slope
medium
moderate
Deep, well drained, moderately sloping to rolling soil on mesas,
terraces, sides of valleys and alluvial fans.
0-5
Fine sandy loam
SM
0.60-6.00
0.11-0.16
1-3
5-30
Sandy clay loam
SC, CL
0.60-2.00
0.13-0.15
30-60
Sandy clay loam
SC, CL
0.60-6.00
0.11-0.15
R7 -Ascalon -Pena
complex, 6 to 25% slope
medium
moderate
Moderately sloping to hilly soils are on sides of valleys an alluvial
fans.
0-5
Fine sandy loam - Ascalon
SM
0.60-6.00
0.11-0.16
1-3
5-30
Sandy clay loam - Ascalon
5C, CL
0.60-2.00
0.13-0.15
30-60
Sandy clay loam - Ascalon
SC, CL
0.60-6.00
0.11-0.15
0-12
Stony Loam - Pena
CL -ML
0.60-2.00
0.12-0.15
1-3
12-60
Very stony loam - Pena
5C
0.60-2.00
0.03-0.08
R9-Badland
rapid
severe
Steep and very steep, nearly barren land dissected by many
intermittent drainage channels.
NA
Not Available
Not Available
Not Available
Not Available
Not Available
R12-Buc
to 50 50% % slope sl
looms, 255 to
medium
severe
Moderately sloping to very steep soils on ridges and mountainsides.
0-4
Loam
CL, CL -ML, ML
0.06-2.00
0.16-0.20
2-5
4-25
Clay loam, Loam, Gravelly loam, Gravelly clay loam
CL, GM -GC, GM, GC
0.06-2.00
0.11-0.18
25-60
Clay loam, Silty clay loam
N/A
0.00-0.00
0.00-0.00
R16 -Cimarron loam, 2 to
12% slope
medium
moderate
Deep, well drained, nearly level to undulating soil in narrow mountain
valleys and drainage ways.
0-4
Loam
ML
0.60-2.00
0.16-0.18
2-4
4-60
Clay, silty clay loam, silty clay
CH, ML
0.06-2.00
0.14-0.16
R17- Cochetopa loam, 9
to 50% sloe
P
slow
severe
Deep, well drained, rolling to steep soil is on mountainsides and
alluvial fans.
0-21
Loam
ML
0.60-2.00
0.16-0.18
3-6
21-60
Clay, stony clay, Stony clay loam
CL, CH
0.06-2.00
0.11-0.14
R21 -Cushman -Lamar
stony loams, 15 to 65%
slope
Not available.
Not available.
Hilly to very steep soils are on mountainsides and mesa banks.
0-4
Stony loam
GM -GC
0.60-2.00
0.08-0.11
0.5-1
4-16
Stony loam
SM -SC
0.60-2.00
0.08-0.11
16
Unweathered bedrock
N/A
N/A
N/A
R24-Dolland-Rock
outcrop, shale, complex,
25 to 65% slope
rapid
very severe
0-5
Clay
CL, CH
0.06-0.20
0.17-0.19
1-2
Complex consists of moderately steep to steep Dollard soil and shale
outcrop on hills and mountainsides.
5-25
Silty clay, Silty clay loam, Clay
CH,CL
0.06-0.20
0.13-0.18
25
Weathered bedrock
N/A
N/A
N/A
R27 -1-l0 aquept0 nearly
level
Not Available
Not Available
Broadly defined unit consists of deep, somewhat poorly drained to
poorlydrained, near) level and
y gently sloping, salt -affected soils in
narrow foothill valleys, on fans, and on low terraces.
0-8
Clay Loam
CH- CL
Not available.
Not available.
Not Available
8-24
Loam
ML
24-60
Gravelly cobbly sand
GM, SM
R28-Heldt clay loam, 1 to
3 % sloe
P
Not available
Not available
Deep, well drained, nearly level soil on alluvial fans and sides of
voile
valleys.
0-8
Clay loam
CH- CL
0.06-0.20
0.12-0.17
i 2
8-60
Silty clay, Clay, Clay loam
CH- CL
0.06-0.20
0.12-0.17
R29 -Held[ clay loam, 3 to
6% slope
P
medium
moderate
Deep, well drained, gently sloping soil on alluvial fans and sides of
valleys.
Y
0-8
Clay loam
CH- CL
0.06-0.20
0.12-0.17
1-2
8-60
Silty clay, Clay, Clay loam
CH- CL
0.06-0.20
0.12-0.17
R30-Heldt clay loam, 6 to
12% sloe
P
medium
moderate
Deep, well drained, moderately sloping to rolling soil on alluvial fans
0-8
Clay loam
CH- CL
0.06-0.20
0.12-0.17
1-2
and sides of valleys.
Y
8-60
Silty clay, Clay, Clay loam
CH- CL
0.06-0.20
0.12-0.17
R31 -Held[ clay loam, 12
to 25% slope
P
medium
moderate
Deep, well drained, moderately steep to hilly soil on alluvial fans and
sides of valla Ys.
0-8
Clay loam
CH- CL
0.06-0.20
0.12-0.17
i 2
8-60
Silty clay, Clay, Clay loam
CH- CL
0.06-0.20
0.12-0.17
R32-Holderness variant
clay loam, 6 to 25%
slope
Not available.
Not available.
Deep, well drained, moderately sloping to hilly soil on alluvial fans
and sides of valleys.
0-11
Clay loam
CL -ML, CL
0.2-0.6
0.15-0.19
2-4
11-30
Clay
CL -CH
0.06-0.20
0.15-0.19
30-60
Clay loam
CL
0.2-0.6
0.15-0.19
R33-I1defonso stony
loam, 6 to 25 % slope
pe
moderate
moderate
Moderately -sloping to hilly, deep, well -drained stony loam formed
from reworked alluvium derived from basalt. Found on mesas,
benches, and the sides of valleys.
0-8
Stony loam
SM, GM
2.00-6.00
0.08-0.10
1-2
8-60
Very stony loam, very gravelly sandy loam.
SM, GM
2.00-6.00
0.06-0.08
0.5-1
R34-I1defonso stony
loam, 2510 45 % slope
pe
moderate
severe
Hilly, deep, well -drained stony loam formed from reworked alluvium
derived from basalt. Found on mesa breaks, alluvial fans and the
sides of valleys.
0-8
Stony loam
SM, GM
2.00-6.00
0.08-0.10
1-2
8-60
Very stony loam, very gravelly sandy loam.
SM, GM
2.00-6.00
0.06-0.08
0.5-1
R35-Ildefonso-Lazear
complex, 6 to 65 % slope
medium/rapid
moderate/severe
Moderately sloping to very steep soils on hillsides and mesa breaks.
0-6
Stony loam, Gravelly loam
SM, GM, ML
0.60-6.00
0.08-0.16
0.5-1
6 16
Very stony loam, Very gravelly sandy loam, Gravelly loam,
Cobbly loam
SMGMML
, ,
0.60-6.00
0.06-0.16
16-60
Very stony loam, Very gravelly sandy loam, Unweathered
bedrock
SM, GM
0.00-0.00
0.00-0.00
F4Projects\014-2797\Documents \Operational Does \SWMP \Appendix C -Mamm Creek Soils Table 021208.x95
Updated February 2008
APPENDIX C
Soils Table - Mamm Creek Unit SWMP
Page 2 of 6
Map Unit Number -
Soil Name
Characteristic Plant Communities
Suitability For:
Small
Commercial
Buildings
Local Roads &
Streets
Roadfill
Topsoil
Pond Reservoir
Areas
Embankments,
Dikes, & Levees
Drainage
Irrigation
Terraces and
Diversions
Grassed
Waterways
R3 -Arvada loam, 1 to 6 %
slope
Western wheatgrass, Alkali sacaton, Inland saltgrass,
Winterfat, Bottlebrush Squirreltail, Gardner saltbmsh,
Greasewood
Severe: shrink -swell.
Severe: shrink -swell,
low strength.
Poor: shrink -swell,
low strength.
Poor: too clayey,Peres
excess sodium.
Favorable
Excess sodium
slowl excess
y'
sdium, slope.
Slo e, eres slowl
p p y'
excess sodium
Peres slowly.
Peres slowly, excess
y'
sodium.
R4 -Arvada loam, 6 to
20% slope
Big sagebrush, Greasewood, Galleta, Shadscale,
Bottlebrush Squirreltail, Western wheatgrass
Severe: slope, shrink-
swell.
Severe: shrink -swell,
low strength.
Poor: shrink -swell,
low strength.
Poor: too clayey,
excess sodium.
Slope
Excess sodium
Peros slowly, excess
sodium, slope.
Slope, percs slowly,
excess sodium.
Slope, pens slowly.
Slope, percs slowly,
excess sodium.
R5 -Ascalon fine sandy
loam, 1 to 6% slope
Needleandthread, Western wheatgrass, Bluebunch
wheatgrass, Big sagebrush, Utah serviceberry
Moderate: low
strength
Moderate: frost
action, low strength.
Poor: low strength.
Fair: too clayey.
Seepage, slope.
Favorable.
Slope.
Slope.
Slope.
Slope.
R6 -Ascalon fine sandy
loam 6 to 12% slope
Needleandthread, Western wheatgrass, Bluebunch
wheatgrass, Big sagebrush, Utah serviceberry
Severe: slope.
Moderate: slope,
frost action, low
strength.
Poor: low strength.
Fair: slope, too
clayey.
Seepage, slope.
Favorable.
Slope.
Slope.
Slope.
Slope.
R7 -Ascalon -Pena
complex 6 to 25% slope
Needleandthread, Western wheatgrass, Bluebunch
wheatgrass, Big sagebrush, Utah serviceberry- Ascalon
Severe: slope.
Moderate: slope,
frost action, low
strength.
Poor: low strength.
Fair: slope, too
clayey.
Seepage, slope.
Favorable.
Slope.
Slope.
Slope.
Slope.
True mountain mahogany, Big sagebrush, Utah
serviceberty, Bluebunch wheatgrass, Western wheatgrass,
Indian ricegrass, Bottlebrush Squirreltail -Pena
Severe: slope, large
stones.
Severe: slope, large
stones.
Poor: large stones.
Peer: slope, large
stones.
Slope, large stones.
Large stones.
Slope, large stones.
Slope, large stones
droughty.
Slope, large stones.
Slope, large stones
droughty.
R9-Badland
Not Available
Not Available
Not Available
Not Available
Not Available
Not Available
Not Available
Not Available
Not Available
Not Available
Not Available
R72-Buckton-Inchau
25 to 50% slope
Gambel oak, Elk sedge, Mountain brome, Utah
serviceber ry'Western wheatgrass, Slender wheatgrass,
snowberry
Severe: depth to
rock, slope.
Severe: depth to
rock, slope, low
strength.
Poorthin layer,
slope, area reclaim.
Poor: slope, area
thin layer,
small stones.
Depth to rock, slope,
seepage.Common
Thin
Slope, depth to rock.
Rootingdepth, slope.
Slope, depth to rock.
Slope, rootingdepth.th.looms,
R16 -Cimarron loam, 2 to
12% slope
Idaho fescue, Bearded wheatgrass, Western wheatgrass,
Mountain brome, Big sagebrush, Muttongrass, Slender
wheatgrass, Needlegrass, Nodding bromegrass
Severe: shrink -swell,
low strength.
Severe: shrink -swell,
low strength.
Poor: shrink -swell,
low strength.
Poor: too clayey.
Slope.
Hard to Pack
Slope, pens slowly.
Peres slowly, slope.
Slope, pares slowly.
Slope, parts slowly.
R17- Cochelopa loam, 9
to 50% slope
Gambel oak, Mountain brome, Utah serviceberry, Elk
sedge, Bearded wheatgrass, Columbia needlegrass,
Mountain snowberry
Severe: shrink -swell,
slope, low strength.
Severe: shrink -swell,
slope, low strength.
Poor: shrink -swell,
slope, low strength.
Poor: slope, small
stones.
Slope.
Hard to Pack
Peres slowly, slope.
Slope, pens slowly.
Peres slowly, slope.
Peres slowly, slope.
R21-Cushman-Lazear
stony looms, 15 to 65%
slope
Not available.
Severe: slop depthp
to rock.
Severe: depth to
rock, slope.
layer,
Poor: thin er, area
y
reclaim.
Poor: slope, small
stones.
Slope, depth of rock.
y g Thin layer, lar a
stones.
Slope, depth to rock.
Slope, rooting depth,
large stones,
droughty.
Slope, de
depth to rock,
large stones,
Slope, dep th to rock,
large stones,
R24-Dolland-Rock
outcrop, shale, complex,
25 to 65 % slope
Western wheatgrass, Muttongrass, Bigsagebrush, Utah
g g g
serviceberry, Arizona fescue, True mountain mahogany
Severe: slope,
pe, shrink-
swell, low strength.
Severe: slope, shrink-
swell, low strength.
Poor thin layer,
slope, low strength.
Poor: slope, too
clayey.
Slope, depth of rock.
Thin layer, hard to
pack.
Depth to rock, slope,
percs slowly.
Slope, pens slowly,
rooting depth.
Depth to rock, pens
slowly, slope.
Slope, pens slowly,
rooting depth.
R27-Halequepts, needy
level
Not Available
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
R28-Heldt clay loam, 1 to
3% slope
Western wheatgrass, Big sagebrush, Green needlegrass,
Squirreltail, Wintertat, Prairie junegrass, Low rabbitbmsh,
Sandberg bluegrass
Severe: shrink -swell,
low strength.
Severe: shrink -swell,
low strength.
Poor: shrink -swell,
low strength.
Poor: too clayey.
Slope
Hard to Pack
Percs slowly, slope.
Slope, percs slowly.
Percs slowly.
Percs slowly.
R29-Heldt clay loam, 3 to
6% slope
Western wheatgrass, Big sagebrush, Green needlegrass,
Squirreltail, Wintertat, Prairie junegrass, Low rabbitbrush,
Sandberg bluegrass
Severe: shrink -swell,
low strength.
Severe: shrink -swell,
low strength.
Poor: shrink -swell,
low strength.
Poor: too clayey.
Slope
Hard to Pack
Peres slowly, slope.
Slope, percs slowly.
Peres slowly.
Peres slowly.
R30-Heldt clay loam, 6 to
12% slope
Western wheatgrass, Big sagebrush, Green needlegrass,
Squirreltail, Wintertat, Prairie junegrass, Low rabbitbmsh,
Sandberg bluegrass
Severe: slope, shrink-
swell, low strength.
Severe: shrink -swell,
low strength.
Poor: shrink -swell,
low strength.
P°or: too clayey.
Slope
Hard to Pack
Peres slowly, slope.
Slope, percs slowly.
Peres slowly, slope.
Slope, percs slowly.
R31-Heldt clay loam, 12
to 25% slope
Western wheatgrass, Big sagebrush, Green needlegrass,
Squirreltail, Winterfat, Prairie junegrass, Low rabbitbrush,
Sandberg bluegrass
Severe: slope, shrink-
swell, low strength.
Severe: slope, shrink-
swell, low strength.
Poor: shrink -swell,
low strength.
Poor: slope, too
clayey.
Slope
Hard to Pack
Percs slowly, slope.
Slope, percs slowly.
Slope, percs slowly.
Slope, percs slowly.
R32-Holderness variant
clay loam, 6 to 25%
slope
Westem wheatgrass, Letterman needlegrass. Muttongrass,
Slender wheatgrass, Prairie junegrass, Big sagebrush,
Utah serviceberry
Severe: slope, shrink-
swell, low strength.
Severe: slope, shrink-
swell, low strength.
Poor: low strength,
shrink -swell.
Poor: slope.
Slope
Hard to Pack
Slope, percs slowly.Sloe,percs
P slowly.Sloe,
percs slow)
P P Y
Slope,
pe, Peres slowly.
R33-1ldefonso stony
loam, 6 to 25% slope
N/A
Severe: slope, large
stones.
Severe: slope, large
stones.
Poor: slope, large
stones.
Poor: slope, large
stones.
Seepage, slope.
Large stones.
Slope, large stones.
Slope, large stones,
droughty.
Large stones, slope.
Slope, large stones,
droughty.
R34-Ildefonso stony
loam, 25 to 45% slope
N/A
Severe: slope, large
stones.
Severe: slope, large
stones.
Poor: slope, large
stones.
Poor: slope, large
stones.
Seepage, slope.
Large stones.
Slope, large stones.
Slope, large stones,
droughty.
Large atones, slope.
Slope, large stones,
droughty.
R35-Ildefonso-Lazear
complex, 6 to 65% slope
Junegrass, Serviceberry, bitterbrush, wheatgrass,
sagebrush.
Severe: slope, large
stones, depth to
rock.
Severe: slope, large
stones, depth to
rock.
Poor: slopethin
,
layer, area reclaim.
Poor: slope, large
stones, small stones,
area reclaim.
Seepage, slope,
depth to rock.
Large stones, thin
layer.
Slope, large stones,
depth to rock.
Slope, large stones,
droughty, rootlng
depth.
Large stones, slope,
depth to rock.
Slope, large stones,
droughty, rooting
depth.
F:\Projects\014-2797\Documents\Operational Does \SWMP \Appendix C -Mamm Creek Soils Table 021208.xds
Updated February 2008
APPENDIX C
Soils Table - Mamm Creek Unit SWMP
Page 3 of 6
Map Unit Number -
Soil Name
Surface
Runoff (slow/
medium/
rapid)
Erosion Potential
(slight/
moderate/
severe)
Soil Description
Soil
Depth
USDA Texture(s)
Unified
Classification
Permeability
(inch/hour)
Available
Water Capacity
(inch/inch)
Organic
Matter
(%)
J
R39 -Jerry loam, 12 to
50% slope
sos
moderate
_
Deep, well drained, strongly sloping to steep soil is on
mountainsides.
0-3
Loam
ML
0.60-2.00
0.16-0.18
3-5
3-40
Gravelly clay loam, cobbly clay loam, cobbly clay
GC, CL, CH
0.06-0.20
0.13-0.15
40-60
Gravelly loam, cobbly clay
GC, CL, CL -ML, GM -GC
0.60-2.00
0.13-0.15
R40 -Kim loam, 3 to 6%
slope
slow
slight
Deep, well drained, gently sloping soil on alluvial fans and benches.
0-60
Loam
ML
0.60-2.00
0.15-0.18
0.5-1
R41 -Kim loam, 6 to 12%
slope
slow
slight
Deep, well drained, moderately sloping to rolling soil on alluvial fans
and benches.
0-60
Loam
ML
0.60-2.00
0.15-0.18
0.5-1
R42-Lamphier loam, 15
to 50% slope
slow
slight
Deep, well drained, steep soil on fans and mountainsides.
0-60
Loam
ML
0.60-2.00
0.18-0.21
2-4
R44-Morval loam, 3 to
12% slope
slow
slight
Deep, well drained, gently sloping to rolling soil on mesas and sides
of valleys.
0-5
Loam
CL
0.60-2.00
0.18-0.21
1-2
5-17
Silty clay loam, clay loam
CL
0.60-2.00
0.14-0.21
17-60
Stony clay loam, stony loam
CL, SC
0.60-2.00
0.08-0.10
R45-Morval-Tridell
complex, 6 to 25% slope
medium
moderate
Moderately sloping to hilly soils are on alluvial fans and sides of
mesas.
0-5
Loam
CL
0.60-2.00
0.18-0.21
1-2
5-17
Silty clay loam, clay loam
CL
0.60-2.00
0.14-0.21
17-60
Stony clay loam, stony loam
CL, SC
0.60-2.00
0.08-0.10
R46-Nihill channeryDeep,
loam, 1 to 6% slope
slow
severe
well drained, gently sloping soil is on alluvial fans and side of
valleys derived from Green River shale and sandstone
Y
0-11
Channery loam
GM, GM -GC, SM, ML
0.60-2.00
0.12-0.16
0 1
11- 60
Very channery loam, very channery sandy loam.
GM, GM -GC
2.00-6.00
0.06-0.09
R50 -Olney loam, 3 to 6%
slope
slow
severe
Deep, well drained, gently sloping soil is on alluvial fans and side of
valleys
Y
0-12
Loam
CL -ML, ML
0.60-2.00
0.15-0.18
1 2
12-33
Sandy clay loam
SC, SM -SC
0.60-2.00
0.14-0.16
33-43
Gravelly sandy clay loam, gravelly sandy loam
SC, SM -SC, GC, GM -GC
0.60-2.00
0.10-0.15
43-60
Very gravelly sandy loam, very gravelly sandy clay loam
GM, GM -GC, GC
0.60-2.00
0.07-0.10
R51 -Olney loam, 6 to
12 % sloe
P
slow
severe
Deep, well drained, moderately sloping to rolling soil on alluvial fans
0-12
Loam
CL -ML, ML
0.60-2.00
0.15-0.18
i 2
12-33
Sandy clay loam
SC, SM -SC
0.60-2.00
0.14-0.16
and sides of valla Ys
33-43
Gravelly sandy clay loam, gravelly sandy loam
SC, SM -SQ, GC, GM -GC
0.60-2.00
0.10-0.15
43-60
Very gravelly sandy loam, very gravelly sandy clay loam
GM, GM -GC, GC
0.60-2.00
0.07-0.10
R54 -Potts loam, 1 to 3%
slope
slow
slight
Deep, well drained soil on mesas, benches, and sides of valleys.
0-4
Loam
ML
0.60-2.00
0.16-0.18
1-2
4-28
Clay loam
CL
0.60-2.00
0.19-0.21
28-60
Loam
ML
0.60-2.00
0.16-0.18
R55 -Potts loam, 3 to 6 %
slope
slow
moderate
Moderately -sloping, deep, well -drained loam and clay loam formed
from in alluvium derived from sandstone, shale, and basalt. Found
on mesas, benches, and the sides of valleys. Y
0-4
Loam
ML
0.60-2.00
0.16-0.18
1-2
4-28
Clay loam
CL
0.60-2.00
0.19-0.21
28-60
Loam
ML
0.60-2.00
0.16-0.18
R56 -Potts 5loam, 6 to
12%slope
12 % pe
moderate
severe
Gently -sloping to rolling, deep, well -drained loam and clay loam
formed from in alluvium derived from sandstone, shale. and basalt.
Found on mesas, benches, and the sides of valleys.
0-4
Loam
ML
0.60-2.00
0.16-0.18
1-2
4-28
Clay loam
CL
0.60-2.00
0.19-0.21
28-60
Loam
ML
0.60-2.00
0.16-0.18
R57-Potts-Ildefonso
complex, 3 to 12% slope
slow
moderate
Gently -sloping to rolling, deep, well -drained loam and clay loam
formed from in alluvium derived from sandstone, shale, and basalt.
Found on mesas and the sides of valleys.
0-4
Loam
ML
0.60-2.00
0.16-0.18
1-2
4-28
Clay loam
CL
0.60-2.00
0.19-0.21
0.5-1
28-60
Loam
ML
0.60-2.00
0.16-0.18
0-0.5
R58-Potts-Ildefonso
complex, 12 to 25%
slope
moderate
moderate
Strongly -sloping to hilly, deep, well -drained loam andclay loam
formed from 5 alluvium derived from sandstone, shale, and basalt.
Found on mesas and the sides of valleys.
0-4
Loam
ML
0.60-2.00
0.16-0.18
1-2
4-28
Clay loam
CL
0.60-2.00
0.19-0.21
0.5-1
28-60
Loam
ML
0.60-2.00
0.16-0.18
0-0.5
R59-Potts-Ildefonso
complex, 25 to 45%
slope
moderate
severe
Hilly to very steep, deep, well -drained loam and clay loam formed
from in alluvium derived from sandstone, shale, and basalt. Found
on alluvial fans and the sides of valleys.
0-4
Loam
ML
0.60-2.00
0.16-0.18
1-2
4-28
Clay loam
CL
0.60-2.00
0.19-0.21
0.5-1
28-60
Loam
ML
0.60-2.00
0.16-0.18
0-0.5
665-Torrifluvents, 0 to
6% slope
Not available.
low
Broadly defined unit consisting of deep, well drained to somewhat
poorly drained, nearly level soils on flood plains adjacent to the
Colorado River and its major tributaries.
Not
available.
The surface layer ranges from loamy sand and fine sandy loam
to silty loam and clay loam. The underlying layers are generally
sandy loam or loam stratified with sand, gravel, and cobbles.
Not available.
Not available.
Not available.
Not
available.
R66-Torriorthents-Exposed
Camhorthids-Rock
outcrop complex, 15 to
70% slope
very rapid
very severe
sandstone and shale bedrock, loose stones, and shallow to
deep stony looms and clay found on toe slopes and concave open
areas on foothills and mountainsides.
0-4
Variable, Unweathered bedrock
CL -ML, ML, SC -SM, SM
0.00-6.00
0.00-0.18
0.5-1
4-30
Clay loam, Fine sandy loam, Loam, Unweathered bedrock
CL, CL -ML, SC -SM, SM
0.00-2.00
0.00-0.18
0-0.5
30-34
Unweathered bedrock
N/A
0.00-0.20
0.00-0.00
0
R67-Torriorthents- Rock
outcrop complex, 15 to
70% slope
very rapid
very severe
Exposed sandstone and shale bedrock, loose stones, and shallow to
deep stony loams and clay found on toe slopes and concave open
areas on foothills and mountainsides.
0-4
Variable, Unweathered bedrock
CL -ML, ML, SC -SM, SM
0.00-6.00
0.00-0.18
0.5-1
4-30
Clay loam, Fine sandy loam, Loam, Unweathered bedrock
CL, CL -ML, SC -SM, SM
0.00-2.00
0.00-0.18
0-0.5
30-34
Unweathered bedrock
N/A
0.00-0.20
0.00-0.00
0
R68 -Vale silt loam, 3 to
6% slope
medium
moderate
Deep, well drained, gently sloping soil on mesas, terraces, and
alluvial fans.
0-11
Silt loam
CL, CL -ML
0.60-2.00
0.19-0.22
2-4
11-26
Silty clay loam, clay loam, silt loam
CL
0.60-2.00
0.17-0.22
26-60
Loam, silty clay loam, silt loam
CL, CL -ML
0.60-2.00
0.13-0.20
R69 -Vale silt loam, 6 to
12% slope
Not available.
Not available.
Deep, well drained, moderately sloping to rolling soil on mesas,
benches, and alluvial fans.
0-11
Silt loam
CL, CL -ML
0.60-2.00
0.19-0.22
2-4
11-26
Silty clay loam, clay loam, silt loam
CL
0.60-2.00
0.17-0.22
26-60
Loam, silty day loam, silt loam
CL, CL -ML
0.60-2.00
0.13-0.20
F:\Projects\014-2797\Documents\Operational Does \SWMP \Appendix C -Mamm Creek Soils Table 021208.x45
Updated February 2008
APPENDIX C
Soils Table - Mamm Creek Unit SWMP
Page 4 of 6
Map Unit Number -
Soil Name
Characteristic Plant Communities
Suitability For:
Small
Commercial
Buildin s
Local Roads &
Streets
Roadfill
Topsoil
Pond Reservoir
Areas
Embankments,
Dikes, & Levees
Drainage
Irrigation
Terraces and
Diversions
Grassed
Waterways
R39 -Jerry loam, 12 to
50% slope
Gambel oak, Sedge, Big sagebrush, Utah serviceberry,
Nodding bromegrass, Big bluegrass, Western wheatgrass,
Slender wheatgrass, Common snowberry
Severe: shrink -swell,
slope.
Severe: shrink -swell,
slope, low strength.
Poor: shrink -swell,
slope, low strength.
Poor: slope, too
clayey, large stones.
Slope
Hard to Pack
Slope, per.slowly.
Slope, peres slowly.
Slope, peres slowly.
Slope, peres slowly.
R40 -Kim loam, 3 to 6 %
slope
Indian ricegrass, Bluebunch wheatgrass, Prairie junegrass,
Muttongrass, Westem wheatgrass, Big sagebrush,
Needleandthread, Low rabbitbrush
Moderate: shrink-
swell, slope.
Moderate: shrink -
swell, low strength.
Fair: low strength.
Good.
Slope, seepage.
Piping.
Slope.
Slope.
Favorable.
Favorable.
R41 -Kim loam, 6 to 12%
slope
Indian ricegrass, Bluebunch wheatgrass, Prairie junegrass,
Muttongrass, Westem wheatgrass, Big sagebrush,
Needleandthread, Low rabbitbrush
Severe: slope.
Moderate: slope,
shrink -swell, low
strength.
Fair: low strength.
Fair: slope.
Slope, seepage.
Piping.
Slope.
Slope.
Slope.
Slope.
R42-Lamphier loam, 15
to 50% slope
Not available
Severe: sloe.
p
Severe: sloe.
p
Poor: sloe.
p
Poor: sloe.
p
pPiping.
Sloe, seepage.
Pi in
Sloe.
p
Sloe.
p
Sloe.
p
Slope.
pe.
R44-Morval loam, 3 to
12% slope
Western wheatgrass, Needleandthread, Big sagebrush,
Bluebunch wheatgrass, Utah serviceberry
Moderate: slope,
shrink -swell.
Moderate: low
strength, shrink
swell, slope.
Fair: low strength,
shrink -swell, frost
action..
Good.
Seepage, slope.
Favorable.
Slope.
Erodes easily, slope.
Erodes easily.
Erodes easily.
R45-Morval-Tridell
complex, 6 to 25% slope
Western wheatgrass, Needleandthread, Big sagebrush,
Bluebunch wheatgrass, Utah serviceberry
Severe: slope, large
stones.
Moderate: low
strength, shrink
swell, slope. Severe:
slope, large stones.
Fair: low strength,
shrink -swell, frost
action. Poor: large
stones.
Fair: slope. Poor:
slope, large stones.
Seepage, slope.
Large stones.
Slope, large stones.
Slope, large stones,
droughty.
Large stones, slope.
Slope, large stones,
droughty.
R46-Nihill channery
loam, 1 to 6% slope
Western wheatgrass, Bluebunch wheatgrass, Big
sagebrush, Needleandthread grass, Indian ricegrass, Low
rabbitbrush
Slight
Slight
Good
Poor: small stones,
area reclaim.
Seepage.
Seepage.
Slope.
Slope, droughty.
Favorable.
Droughty.
R50-01ney loam, 3 to 6%
slope
Western wheatgrass, Bluebunch wheatgrass, Big
sagebrush, Needleandthread grass, Indian ricegrass,
Rabbitbrush
Slight
Slight
Fair: low strength.
Fair: small stones.
Slope, seepage.
Favorable.
Slope.
Slope.
Slope.
Slope.
R51 -Olney loam, 6 to
12% slope
Western wheatgrass, Bluebunch wheatgrass, Big
sagebrush, Needleandthread grass, Indian ricegrass,
Rabbitbrush
Severe: slope.
Severe: slope.
Fair: low strength.
Fair: small stones,
slope.Slope,
seepage.
Favorable.
Slope.
Slope.
Slope.
Slope.
R54 -Potts loam, 1 to 3%
slope
Western wheatgrass, Needleandthread, Bluebunch
wheatgrass, Big sagebrush, Indian ricegrass, Low
rabbitbrush, Squirreltail
Slight
Slight
Fair: low strength.
Fair: small stones.
Seepage.
Piping.
Slope.
Slope, erodes easily.
Erodes easily.
Erodes easily.
R55 -Potts loam, 3 to 6%
slope
Western wheatgrass, Needleandthread, Bluebunch
wheatgrass, Big sagebrush, Indian ricegrass, Low
rabbitbrush, Squirreltail
Moderate: slope.
Slight
Fair: low strength.
Fair: small stones.
Seepage.
Piping.
Slope.
Slope, erodes easily.
Erodes easily.
Erodes easily.
R56 -Potts loam, 6 to
12% slope
Western wheatgrass, Needleandthread, Bluebunch
wheatgrass, Big sagebrush, Indian ricegrass, Low
rabbitbrush, Squirreltail
Severe: slope.
Moderate: slope.
Fair: low strength.
Fair: slope, small
stones.
Seepage.
Piping.
Slope.
Slope, erodes easily.
Slope, erodes easily.
Slope, erodes easily.
R57-Potts-Ildefonso
complex 3 to 12% slope
Western wheatgrass, Needleandthread, Bluebunch
wheatgrass, Big sagebrush, Indian ricegrass, Low
rabbitbrush, Squirteltail
Moderate/Severe:
slope, large stones.
stones. large
o,
stones.
Fair/Poor: low
strength, large
stones.
Fair/Poor: small
stones, large stones.
Seepage, slope.
Piping, large stones.
Slope, large stones.
Slope, erodes easily,
large stones,
droughty,
Erodes easily, large
stones, slope.
Erodes easily, slope,
large stones,
droughty.
R58-Potts-Ildefonso
complex, 12 to 25 %
slope
Western wheatgrass, Needleandthread, Bluebunch
wheatgrass, Big sagebrush, Indian ricegrass, Low
rabbitbrush, Squirreltail
Severe: slope, large
stones.
Severe: slope, large
stones.
Fair/Poor: slope, low
strength, large
stones.
Poor: slope, large
stones.
Seepage, slope.
Piping, large stones.
Slope, large stones.
Slope, erodes easily,
large stones,
droughty.
Slope, erodes easily,
large stones.
Slope, erodes easily,
large stones,
droughty.
R59-Potts-Ildefonso
complex, 25 to 45%
slope
Western wheatgrass, Needleandthread, Bluebunch
wheatgrass, Big sagebrush, Indian ricegrass, Low
rabbitbrush, Squirreltail
Severe: slope, large
stones.
Severe: slope, large
stones.
Poor: slope, large
stones.
Poor: slope, large
stones.
Seepage, slope.
Piping, large stones.
Slope, large stones,
Slope, erodes easily,
large stones,
droughty.
Slope, erodes easily,
large stones.
Slope, erodes easily,
large stones,
droughty.
R65-Torrifluvents, 0 to
6% slope
Cottonwood, Willow, Tamarisk, Water -tolerant grasses,
sedges, and rushes.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
R66-Torriorthents-
Cambodhids-Rock
outcrop complex, 15 to
70% slope
Not available.
Not rated
Not rated
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
R67-Torriorthents- Rock
outcrop complex, 15 to
70% slope
Not available.
Not rated
Not rated
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
Not available.
R68 -Vale silt loam, 3 to
6% slope
Westem wheatgrass, Prairie sandreed, Needleandthread,
Blue grams, Green needlegrass, Rabbitbrush, Utah
Serviceberry
Moderate: slope.
Moderate: low
strength.
Poor: low strength.
Good.
Seepage.
Piping.
Favorable.
Favorable.
Erodes easily.
Erodes easily.
R69 -Vale silt loam, 6 to
12% slope
Western wheatgrass, Prairie sandreed, Needleandthread,
Blue grams, Green needlegrass, Rabbitbrush, Utah
Serviceberry
Severe: slope.
Moderate: slope, low
strength.
Poor: low strength.
Fair: slope.
Slope, seepage.
Piping.
Slope.
Slope.
Erodes easily, slope.
Slope, erodes easily.
F:\Projects\014-2797\Documents\Operational Does \SWMP \Appendix C -Mamm Creek Soils Table 021208.xds
Updated February 2008
APPENDIX C
Soils Table - Mamm Creek Unit SWMP
Page 5 of 6
Map Unit Number -
Soil Name
Surface
Runoff (slow/
medium/
rapid)
Erosion Potential
(slight/
moderate/
severe)
Soil Description
Soil
Depth
USDA Texture(s)
Unified
Classification
Permeability
(inch/hour)
Available
Water Capacity
(inch/inch)
Organic
Matter
(%)
R70 -Vale silt loam, 12 to
25% slope
Not available.
Not available.
Deep, well drained, strongly sloping to hilly soil on mesas, mesa
sides, and alluvial fans.
0-11
sot loam
CL, CL -ML
0.60-2.00
0.19-0.22
2-4
11-26
Silty clay loam, clay loam., silt loam
CL
0.60-2.00
0.17-0.22
26-60
Loam, silty clay loam, silt loam
CL, CL -ML
0.60-2.00
0.13-0.20
R71 -Villa Grove-Zoltay
loams, 15 to 30 % slope
slow/medium
slight/moderate
Moderately steep to hilly soils on mountainsides and alluvial fans.
0-4
Loam
CL
0.20-2.00
0.16-0.19
2-4
4-17
Clay loam, Sandy clay loam, Gravelly clay, Cobbly clay, Cobbly
clay loam
CL, SC, GC
0.60-6.00
0.10-0.19
17-60
Sandy loam, Loam, Gravelly clay, Cobbly clay, Cobbly clay loam
SM -SC, CL -ML, CL, GC,SC
0.06-2.00
0.13-0.16
R72-Wann sandy loam, 1
to 3% slope
slow
moderate
Deep, somewhat poorly drained, nearly level to gently sloping, low-
lying soil on terraces and bottom land in valleys.
0-17
Sandy loam
SM, SM -SC
2.00-6.00
0.16-0.18
3 6
17-60
Sandy loam, Fine sandy loam, Coarse sandy loam
SM, SM -SC
2.00-6.00
0.15-0.17
`The R preceding the soil number represents the Soil Survey of Rifle Area, Colorado.
F:\Projects\014-2797\Documents\Operational Does \SWMP \Appendix C -Mamm Creek Soils Table 021208.xds Updated February 2008
APPENDIX C
Soils Table - Mamm Creek Unit SWMP
Page 6 of 6
Map Unit Number -
Soil Name
Characteristic Plant Communities
Suitability For:
Small
Commercial
Buildings
Local Roads &Pond
Streets
Roadfill
Topsoil
Reservoir
Areas
Embankments,
Dikes, & Levees
Drainage
Irrigation
Terraces and
Diversions
Grassed
Waterways
R70 -Vale silt loam, 12 to
25% slope
Western wheatgrass, Prairie sandreed, Needleandthread,
Blue grama, Green needlegrass, Rabbitbrush, Utah
Serviceberry
Severe: slope.
Severe: slope.
Fair: low strength,
slope.Poor:
slope.
Slope. seepage.
F',pl-:g.
Slope.
Slope.
Slope, erodes easily.
Slope, erodes easily.
R71 -Villa Grove-Zoltay
loams, 15 to 30% slope
Gambel oak, Utah serviceberry, Western wheatgrass, Elk
sedge, Mountain brome, Mountain snowberry
Severe: slope, shrink-
swell.
Severe: slope, low
swell. strength, shrink-
Poor: low strength,
shrink -swell.
Poor: slope, small
stones.
Slope, seepage.
Favorable.
Slope, excess salt,
percs slowly.
Slope, excess salt,
pens slowly.
Favorable, slope,
pens slowly.
Excess salt, slope,
pens slowly.
R72-Wann sandy loam, 1
to 3% slope
Alkali sacaton, Saltgrass, Baltic rush, Low rabbitbrush,
Skunkbush shumac, Sedge
Severe: floods.
Severe: floods, frost
action.
Fair: low strength,
wetness.
Good.
Seepage.
Seepage.
Floods, frost action.
Floods.
Favorable.
Favorable.
'The R preceding the soil number represents the Soil Survey of Rifle Area, Colorado.
F:\Projects\014-2797\Documents\Operational Does \SWMP \Appendix C -Mamm Creek Soils Table 021208.xds
Updated February 2008
Appendix D
Master SWMP Permit Area Map
*tgil*‘b*
F:\Projects\014-2797\Documents\O pe rati on a l
Docs\SWMP\1. Mamm_Creek_SWMP_20101210.doc
Updated February 2008
RIVER s«
BM 5360
Pref Ant34ne
Rifle
Cern
1 Pits e
SJ>9
istif
►fir
IMF
B
23B
,
�cF23�
5950
G25NW
H26NW
F25NW
7'
25NW
,N25NW
M27NW
027NW
P26BX
oq
EAST MAMM
CREEK
COMPRE
029NE
J( A33NW
B33NE
/ J
D 4NE
K33NW
G32C
32
G32B
Well
E33NE
.5985
'5972 As
Wall
.3
H36X
P33B11 aCO
p33
N34NW
:N34NW
N36NWB
itNo Access
K41)W
M3
M3A
Flatiron
WATER
TREATMENT
PACILITY
114E
o I
C OlE
No Access
ravel
FIIE 6322
1113 1
COMPRESSOR
ST 11 /ON'
„6408
Log
Mesa
Cony,.
No Access
DI3W
CI7AE\
K13242
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M23W _ 1
'o
N23W
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ri "rt
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6988
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o BISE ro
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eint1 � o
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� r � •�.,` ' ►t l / " `ire
PISE
7399
EFINITE
16
TONAL
8400
920o
Legend =
EnCana Oil & Gas (USA) Inc.
10343
Mamm Creek Unit SWMP Boundary
COR 034840
T6S-T8S, R92W-R94W, 6th P.M.
11eled Server, 9
(435) 781-2501
180 North Vernal Ave. Vernal, Utah 84078
SCALE 1" = 2,000'
DRAWN BY: mw
Existing Road
Proposed Access
Gas Pipeline
SWMP Boundary Line
Appendix E
Stormwater Manual of Best Managem
F:\Projects\014-2797\Documents\O pe rati on a l
Docs\SWMP\1. Mamm_Creek_SWMP_20101210.doc
Updated February 2008
Prepared for:
EnCana Oil & Gas (USA) Inc.
Parachute, CO 81635
Stormwater Manual of Best
Management Practices (BMPs)
June 2008
Prepared for:
EnCana Oil & Gas (USA) Inc.
Parachute, CO 81635
Stormwater Manual of Best
Management Practices (BMPs)
June 2008
Contents
1.0 Introduction 1
2.0 Planning 2
3.0 Types of Best Management Practices 3
4.0 Principles and practices of erosion control 4
5.0 Erosion control concepts 5
6.0 Selection and implementation of controls 6
7.0 Inspection and maintenance 7
8.0 References 8
Figures
Site Isometrics
SI -1 Site Isometric — Flat and Gently Sloping Terrain
SI -2 Site Isometric — Steep Terrain
Site Plans
SP -0 Site Plan — Preconstruction
SP -1 Site Plan — Flat and Gently Sloping Terrain
SP -2 Site Plan — Steep Terrain
Details
D-1 Access Road Intersection — Well Pad below Road
D-2 Access Road Intersection — Well Pad above Road
D-3 Well Pad
D-4 Road Parallel to Gathering Line and Stream
D-5 404 Stream Crossing
D-6 Gathering Line Crossing Stream (During Construction Condition)
Best Management Practices (BMPs)
Erosion Control BMPs:
Erosion Control Blanket (ECB)
Hydraulic Mulching (HM)
Land Grading (LG) — Roads
Low Water Crossing (LWC)
Mulching (M)
Retaining Wall (RW)
Revegetation (RV)
Riprap (R)
Soil Stabilizers (SS)
Stockpiling (SP) — Topsoil and Subsoil
Surface Roughening (SR)
Terracing (T)
Turf Reinforcement Mat (TRM)
Vegetated Buffer (VB)
Wattles (W)
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM i June 2008
Final for revised pages06-09-08.doc
Contents (continued)
Drainage Control BMPs:
Berm (B)
Culvert (C)
Culvert Inlet Protection (CIP)
Culvert Outlet Protection (COP)
Diversion (D)
Drainage Dip (DD)
Level Spreader (LS)
Roadside Ditches (RSD) and Turnouts (TO)
Run -On Diversion (ROD)
Slope Drain (SD)
Trench Breaker (TB)
Water Bar (WB)
Sediment Control BMPs:
Check Dam (CD)
Detention Pond (DP)
Filter Berm (FB)
Sediment Reservoir (SedR)
Sediment Trap (ST)
Silt Fence (SF)
Slash (SL)
Stabilized Construction Entrance (SCE)
Straw Bale Barrier (SBB)
Wattles (W) — BMP is provided with erosion controls
Non-Stormwater BMPs:
Dewatering (DW)
Dust Control (DC)
Material Delivery and Storage (MDS)
Scheduling (S)
Spill Prevention and Control (SPC)
Vehicle and Equipment Maintenance (VEM)
Waste Management (WM)
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM II June 2008
Final for revised pages06-09-08.doc
1.0 Introduction
The primary purpose of this Stormwater Manual of Best Management Practices (BMPs) is to provide EnCana
personnel, contractors, and subcontractors with information on the proper selection, design, installation, and
maintenance of BMPs to manage oil and gas (O&G) related stormwater and to meet federal and state
Stormwater Management Plan (SWMP) implementation requirements. The BMPs found in this manual are
operating practices that may be used to control erosion, drainage, and sedimentation associated with
stormwater runoff from areas disturbed by clearing, grading, and excavating activities related to site
preparation and construction of oil and gas production facilities. Although the BMPs in this manual were
derived from both common industry practices and from practical field experience, they may not be applicable
for certain sites and field conditions.
Personnel responsible for stormwater management, whether it is design, construction, maintenance, or
environmental compliance, should have a thorough knowledge of the applicable erosion and sediment control
measures and the related specifications.
The main objectives of this manual are to:
1. Serve as an easy-to-use guide for selecting, designing, constructing, and maintaining BMPs.
2. Function as a reference for construction plans and specifications.
3. Ultimately lead to the avoidance of any net increase in off-site erosion and sedimentation of waters of
the U.S.
In the preparation of this document, emphasis was placed on the selection and practical application of BMPs,
given a variety of basic physical circumstances. The series of figures within this document are provided as a
tool to quickly evaluate which BMPs may be useful at a given construction site, whether new or existing. This
document anticipates that the user will be prudent and exercise good judgment in evaluating site conditions
and deciding which BMP or combination of BMPs is to be used at a specific site. If the BMPs selected are not
effective to prevent discharges of potentially undesirable quantities of sediment to a regulated water body,
different or additional BMPs should be employed.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 1 June 2008
Final 06-09-08.doc
2.0 Planning
Planning for the inclusion of appropriate BMPs should occur early in the site development process, and can be
divided into five separate steps:
1. Site Assessment — Collect the information from the site regarding topography, soils, drainage,
vegetation, and other predominant features. Also make note of any existing erosion that is present.
Analyze the information to anticipate erosion and sedimentation problems.
2. Avoidance and Minimization — Avoiding or minimizing disturbances on construction sites are the best
protection measures against erosion and sedimentation problems. Inclusion of these measures will
also decrease the amount of BMPs required during construction.
3. Construction Scheduling and Phasing — Develop a construction schedule and phasing plan that
minimizes the amount of area exposed thus minimizing erosion and impacts to the area from
development.
4. SWMP — Develop and implement a SWMP that specifies effective BMPs, taking into consideration
the information generated from the site assessment and the construction schedule and phasing.
5. Inspections and Maintenance — Inspection and maintenance of BMPs are required by the SWMP.
Evaluate the BMPs that will be implemented and allocate the necessary resources to provide for
timely and thorough inspections and maintenance.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 2 June 2008
Final 06-09-08.doc
3.0 Types of Best Management Practices
Erosion Control — any source control practice that protects the soil surface and/or strengthens the subsurface
in order to prevent soil particles from being detached by rain or wind, thus controlling raindrop, sheet, and/or rill
erosion.
Drainage Control — any practice that reduces or eliminates gully, channel, and stream erosion by minimizing,
diverting, or conveying runoff through engineered systems.
Sediment Control — any practice that traps the soil particles after they have been detached and moved by wind
or water. Sediment control measures are usually passive systems that rely on filtering or settling the particles
out of the water or wind that is transporting them prior to leaving the site boundary.
Non-Stormwater Control — any general site and materials management measure that indirectly aids in
minimization of erosion and pollution of water. Types of pollution sources include, but are not limited to, litter,
oil and grease, hazardous material spills, and sediment.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 3 June 2008
Final 06-09-08.doc
4.0 Principles and practices of erosion control
Types of erosion
Splash Energy from the raindrop dislodges soil particles and initiates the erosion process.
Sheet Uniform removal of saturated soil particles.
Rill
Gully
Long, narrow incisions in the soil caused by increased runoff velocities.
Deep, wide incisions caused by concentrated flow.
Streambank Bank sloughing, toe cutting in a natural
drainage pattern.
Factors affecting erosion
Soil type
The primary soil property that affects erosiveness is the
cohesiveness of the soil. While there are other factors, this is
the most dominant factor when considering temporary erosion
controls. The generalized soil triangle shows the break
between soils that can be considered cohesive or noncohesive
soils. This rule of thumb has to be applied with good
professional judgment.
4xr IL sr1J
Vegetation
Vegetation is the primary permanent erosion control for un -stabilized exposed surfaces. Anytime the existing
vegetation is removed, there is immediate potential for wind and water erosion. Therefore, any un -vegetated
surface should be treated with an appropriate BMP to prevent surface erosion. The appropriate BMP depends
on the other factors affecting erosion.
Climate
The key climatic factors affecting erosion are rainfall intensity, duration, and return frequency, which in turn
determine soil particle detachment and transport in runoff. Other climatic properties, such as temperature and
growing season, have more to do with reestablishing permanent erosion controls.
Topography
The slope and length of slope have a direct influence on the transport of dislodged sediment and soil particles
down slope. Even very erosive soils on flat slopes will not produce large amounts of sediment because there
is not sufficient potential gravitational force to accelerate the surface runoff to velocities that will suspend and
transport sediments. As slopes become steeper, the velocity of flow of surface runoff increases with a
subsequent increase in sediment loads. That is why velocity management is a critical part of any erosion
control practice.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 4 June 2008
Final 06-09-08.doc
5.0 Erosion control concepts
Surface protection
Protecting the soil surface will help minimize the amount of soil that is detached and transported as sediment.
Minimization of concentrated flows
Concentrated flows generate more energy and velocity than sheet flows. Greater depths and velocity
generate more erosion and suspension of eroded materials. If concentrated flows develop, BMPs, such as
check dams, can be used to reduce the velocity. Where concentrated flows are directed to uniform surfaces,
level spreaders can be used to reestablish sheet flows.
Velocity reduction
Velocity reduction is a key component of BMP strategies. Control measures such as rock check dams,
wattles, etc., are placed perpendicular to the direction of flow, whether sheet flow or concentrated flow, to slow
the velocity of the water. The BMP type must be selected based on the anticipated depth, velocity, and
frequency of flows over the surface or in the channel.
Sediment capture
Effective sediment control measures are designed and implemented to slow the runoff velocity and retain the
sediment -laden water to allow soil particles to fall from suspension and settle out of the runoff. This will
facilitate transport reduction and thereby the quantities of sediment that leave the site.
Runoff management
Runoff management tools are designed to utilize proper grading, diversions, barriers, or interceptor ditches to
minimize concentrated flows and divert runoff away from denuded slopes or other critical areas. This can be
done by minimizing slope steepness and length through the use of terraces, interceptor berms or ditches or
diversion ditches. The concept is to divert clean runoff before it becomes sediment laden.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 5 June 2008
Final 06-09-08.doc
6.0 Selection and implementation of controls
Implementation of BMPs will be successful if used appropriately, taking into account a number of factors. The
following are guidelines recommended in determining the appropriate BMPs for the site:
1. Determine the limits of clearing and grubbing. If the entire site will not undergo excavation and
grading, the boundaries of cut -and -fill operations should be defined. Buffer strips of natural
vegetation may be utilized as a control measure.
2. Define the layout of buildings and roads. This will have been decided previously as part of the
general development plan. If building layout is not final, the road areas stabilized with pavement and
the drainage features related to roads should be defined as they relate to the plan.
3. Determine permanent drainage features. The location of permanent channels, storm sewers,
roadside swales, and stormwater quality controls such as ponds, wetlands, grassed -lined swales,
buffer strips, and areas of porous pavement, if known, should be defined.
4. Determine extent of temporary channel diversions. If permanent channel improvements are a part of
the plan, the route, sizing, and lining needed for temporary channel diversions should be determined.
Location and type of temporary channel crossings can be assessed.
5. Determine the boundaries of watersheds. The size of drainage basins will determine the types of
sediment controls to be used. Areas located off site that contribute overland flow runoff must be
assessed. Measures to limit the size of upland overland flow areas, such as run-on diversions, may
be initially considered at this stage.
6. Select erosion controls. All areas exposed will require a control measure be defined dependent on
the duration of exposure. These can be selected based on the schedule of construction.
7. Select sediment controls. Areas greater than 5 acres will require the installation of sediment basins.
Consideration can be given to dividing large drainage basins into sub -areas, each served by a
sediment basin.
8. Determine staging areas. The schedule of construction will determine what areas must be disturbed
at various stages throughout the development plan. The opportunity for staging cut -and -fill
operations to minimize the period of exposure of soils can be assessed. The sequence for installing
sediment controls and erosion controls can also be determined at this time.
9. Identify locations of topsoil and other stockpiles.
10. Identify location of construction roads, access points, and material storage areas.
Once BMPs have been selected, each control should be incorporated into a site-specific plan drawing as a
requirement of the SWMP. Each of the following BMPs includes design criteria (to properly locate and size
each control) and construction specifications (to properly install the control with the appropriate materials and
methods), if applicable.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 6 June 2008
Final 06-09-08.doc
7.0 Inspection and maintenance
All BMPs must be properly inspected and maintained throughout the life of the entire operation according to
the "Maintenance Considerations" section in each of the following BMPs. In general, the maintenance
program should provide for inspection of BMPs on a regular basis in accordance with the SWMP. Inspection
of BMPs should also occur as soon as possible after major rainfall events, particularly at sensitive areas in
proximity to a perennial drainage. The inspection should include repair or replacement of the BMPs, where
needed, to ensure effective and efficient operation.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 7 June 2008
Final 06-09-08.doc
8.0 References
Arizona Department of Transportation (ADOT), Erosion and Pollution Control Manual. February, 2005.
<http://www.azdot.gov/ADOT_and/Storm_Water/Erosion_Pol lution_Control_Manual.asp>
California Stormwater Quality Association, Stormwater Best Management Practice (BMP) Handbook —
Construction. January, 2003. <http://www.cabmphandbooks.com/Construction.asp>
City of Knoxville, Stormwater Engineering, Knoxville BMP Manual - Best Management Practices. July 2003.
<http://www.ci.knoxville.tn.us/engineering>
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
<http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Federal Energy Regulatory Commission (FERC), Upland Erosion Control, Revegetation, and Maintenance
Plan. January 2003.
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
Maine Department of Conservation, Best Management Practices for Forestry: Protecting Maine's Water
Quality. Maine Forest Service, Forest Policy and Management Division. Augusta, Maine. 2004.
<http://www.state.me.us/doc/mfs/pubs/pdf/bmpmanual/bmpmanual.pdf>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
South Dakota Department of Transportation — Water Quality Enhancement Program, Construction Field
Manual — Construction Site Management and Erosion and Sediment Control. South Dakota.
United States Army Corps of Engineers (USACE), Engineering and Design - Handbook for the Preparation of
Storm Water Pollution Prevention Plans for Construction Activities. February 1997.
<http://www.usace.army.mil/inet/usace-docs/eng-pamphlets/ep1110-1-16/>
United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), Field
Office Technical Guide. 2002. <www.nrcs.usda.gov/technical/efotg>
United States Department of the Interior and United States Department of Agriculture. Surface Operating
Standards and Guidelines for Oil and Gas Exploration and Development "Gold Book."
BLM/WO/ST-06/021+3071. Bureau of Land Management (BLM). Denver, Colorado. Fourth
Edition, 2006.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM 8 June 2008
Final 06-09-08.doc
SURFACE
WATER
FLOW
CUT SLOPE
EROSION CONTROL
SEDIMENT CONTROL
(i.e. SEDIMENT TRAP (ST)) (TYP.)
EROSION CONTROL
(i.e. WATTLE (W)) (TYP.)
:DETENTION
POND (DP)
FILL SLOPE
EROSION CONTROL
WATTLE (W)(TYP.)
SURFACE
WATER
FLOW
\ \ \
SEDIMENT
RESERVOIR (SEDR) GATHERING LINE
TOPSOIL STOCKPILE (SP) �- - ______
17.
-
SEDIMENT CONTROL
(i.e. CHECK DAM (CD))
CULVERT (C)
GATHERING LINE
•
SEDIMENT
RESERVOIR
(SEDR)
SEDIMENT CONTROL::`5 .c
i.e. SEDIMENT TRAP (ST)) (TYP.) h'•
EROSION CONTROL -'
i.e. WATTLE (W)) (TYP.)
ENSRIAECOM
NOT TO SCALE
LEGEND
CUT SLOPE
FILL SLOPE
ROADSIDE DITCH (RSD)
DIVERSION (D) OR (ROD)
BERM (B)
TOPSOIL STOCKPILE (TS)
EROSION CONTROL
BLANKET (ECB)
WATTLE (W)
•
RIPRAP (R)
VEGETATED
BUFFER (VB)
CHECK DAM (CD)
SEDIMENT TRAP (ST)
GROUND SURFACE
CONTOUR (BEFORE
CONSTRUCTION)
FLOW
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
DATE: 05/30/08
DRWN: E.S.S./GOL
SEDIMENT CONTROL
CHECK DAM (CD)
FILTER BERM (FB)
SEDIMENT TRAP (ST)
SILT FENCE (SF)
WATTLE (W)
OPTIONS EROSION CONTROL OPTIONS
EROSION CONTROL BLANKET
(ECB)
HYDRAULIC MULCHING (HM)
MULCHING (M)
RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
SITE ISOMETRIC
FLAT AND GENTLY SLOPING TERRAIN
FIGURE SI -1
WilEncono BMP Monuol ENC—BMPM_S/-2.OWG Lo out: f7GURE 51-2 User. eschneider Plotted: Jun 09, 2008 — 2:•02'm Xrefs
TOPSOIL STOCKPILE (SP)
SEDIMENT CONTROL
'.'(i.e. WATTLES (W)) (TYP.) \�
SEDIMENT CONTROL
(i.e. SEDIMENT TRAP (ST)) (TYP.)
SEDIMENT CONTROL
CHECK DAM (CD)
FILTER BERM (FB)
SEDIMENT TRAP (ST)
SILT FENCE (SF)
WATTLE (W)
OPTIONS EROSION CONTROL OPTIONS
EROSION CONTROL BLANKET
(ECB)
HYDRAULIC MULCHING (HM)
MULCHING (M)
RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
SEDIMENT CONTROL
(i.e. SEDIMENT TRAP (ST)) (TYP.)
-----------------------------
--------------------------- -SURFACE q
WATER
FLOW
File: M:l Encono l BMP ManuaIl dwgs l ENC-BMPM_SP-O. DWG Layout: FIGURE SP-0 User: eschneider Plotted: dun 09 2008 - 2:02pm Xref s:
GROUND SURFACE
CONTOUR (BEFORE
CONSTRUCTION)
DIVERSION (D) OR (ROD)
VEGETATED BUFFER (VB)
SEDIMENT CONTROL �.
(i.e. SEDIMENT TRAP (ST)) (TYP.)
EROSION CONTROL
(i.e. WATTLE (W))(TYP.)
SEDIMENT CONTROL OPTIONS EROSION CONTROL OPTIONS
CHECK DAM (CD) EROSION CONTROL BLANKET
FILTER BERM (FB) (ECB)
SEDIMENT TRAP (ST) HYDRAULIC MULCHING (HM)
SILT FENCE (SF) MULCHING (M)
WATTLE ON) RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
File: M.• Encano BMP Manuall dwgs l ENC-BMPM_ SP -1 and Ds.DWG Layout.: FIGURE SP -1
SURFACE
WATER
FLOW
D-1
STABILIZED CONSTRUCTION
ENTRANCE (SCE)
ROAD —*
CROWN
l
---- _ GROUND SURFACE
CONTOUR (BEFORE CONSTRUCTION)
------------------
SEDIMENT CONTROL
(i.e. CHECK DAM (CD)) (TYP.)
SURFACE /L
WATER
FLOW
rD-2
--__ RUN ON DIVERSION (ROD)
----------------------------------
CUT SLOPE
EROSION CONTROL
D-3
4
DIVERSION (D)
— BERM (B) _
FRACING -
PIT
WELL HEADS
SURFACE
WATER
FLOW
DETENTION
- POND (DP)
ROADSIDE
DITCH (RSD)
CROWN
4
FILL SLOPE ��P
•'EROSION CONTROL
SEDIMENT
RESERVOIR (SEDR)::::
`,/
... .''.•.'.'.
• TOPSOIL STOCKPILE (SP)
____TURNOUT (TO) GATHERING LINE
RUN ON DIVERSION (ROD) . EROSION CONTROL ON
WATTLE (W) (TYP) •:: •
'GATHERING LINE
VEGETATED
BUFFER
OR SEDIMENT
CONTROL
(i.e. WATTLE(W)) ... .
EROSION CONTROL
(i.e. EROSION CONTROL . .
BLANKET (ECB))
ENSR AECOM
SEDIMENT CONTROL
(i.e. SEDIMENT TRAP (ST))(TYP.)
EROSION CONTROL
(i.e. WATTLE (W))(TYP.)
BERM --
SEDIMENT RESERVOIR (SEDR)
TOPSOILSTOCKPILE•.
. (SP)
SLASH (SL)
:' WATTLE (W) (TYP.)
NOT TO SCALE
BMW
LEGEND
CUT SLOPE
FILL SLOPE
ROADSIDE DITCH (RSD)
DIVERSION (D) OR (ROD)
BERM (B)
TOPSOIL STOCKPILE (TS)
EROSION CONTROL
BLANKET (ECB)
WATTLE (W)
•
RIPRAP (R)
VEGETATED
BUFFER (VB)
CHECK DAM (CD)
SEDIMENT TRAP (ST)
GROUND SURFACE
CONTOUR (BEFORE
CONSTRUCTION)
FLOW
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
DATE: 06/06/08
DRWN: E.S.S./GOL
SEDIMENT CONTROL
CHECK DAM (CD)
FILTER BERM (FB)
SEDIMENT TRAP (ST)
SILT FENCE (SF)
WATTLE (W)
OPTIONS EROSION CONTROL OPTIONS
EROSION CONTROL BLANKET
(ECB)
HYDRAULIC MULCHING (HM)
MULCHING (M)
RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
SITE PLAN
FLAT AND GENTLY SLOPING TERRAIN
FIGURE SP -1
T
W_
I.
DIVERSION (D)
— BERM (B) _
FRACING -
PIT
WELL HEADS
SURFACE
WATER
FLOW
DETENTION
- POND (DP)
ROADSIDE
DITCH (RSD)
CROWN
4
FILL SLOPE ��P
•'EROSION CONTROL
SEDIMENT
RESERVOIR (SEDR)::::
`,/
... .''.•.'.'.
• TOPSOIL STOCKPILE (SP)
____TURNOUT (TO) GATHERING LINE
RUN ON DIVERSION (ROD) . EROSION CONTROL ON
WATTLE (W) (TYP) •:: •
'GATHERING LINE
VEGETATED
BUFFER
OR SEDIMENT
CONTROL
(i.e. WATTLE(W)) ... .
EROSION CONTROL
(i.e. EROSION CONTROL . .
BLANKET (ECB))
ENSR AECOM
SEDIMENT CONTROL
(i.e. SEDIMENT TRAP (ST))(TYP.)
EROSION CONTROL
(i.e. WATTLE (W))(TYP.)
BERM --
SEDIMENT RESERVOIR (SEDR)
TOPSOILSTOCKPILE•.
. (SP)
SLASH (SL)
:' WATTLE (W) (TYP.)
NOT TO SCALE
BMW
LEGEND
CUT SLOPE
FILL SLOPE
ROADSIDE DITCH (RSD)
DIVERSION (D) OR (ROD)
BERM (B)
TOPSOIL STOCKPILE (TS)
EROSION CONTROL
BLANKET (ECB)
WATTLE (W)
•
RIPRAP (R)
VEGETATED
BUFFER (VB)
CHECK DAM (CD)
SEDIMENT TRAP (ST)
GROUND SURFACE
CONTOUR (BEFORE
CONSTRUCTION)
FLOW
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
DATE: 06/06/08
DRWN: E.S.S./GOL
SEDIMENT CONTROL
CHECK DAM (CD)
FILTER BERM (FB)
SEDIMENT TRAP (ST)
SILT FENCE (SF)
WATTLE (W)
OPTIONS EROSION CONTROL OPTIONS
EROSION CONTROL BLANKET
(ECB)
HYDRAULIC MULCHING (HM)
MULCHING (M)
RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
SITE PLAN
FLAT AND GENTLY SLOPING TERRAIN
FIGURE SP -1
File: M.• Encana l BMP Manual) dwgs l ENC-BMP41 SP-2.DWG Layout.: FIGURE SP -2 User: eschneider Plotted: dun 09, 2008 - 1.56pm Xref's:
RUN ON DIVERSION (ROD)
=11111 111-
1=111-111-=
I1 111 1Ii=ll l=
lll--I 11E111E11 5111E111E111.1E111E11 .. EROSION CONTROL
=111=l1l=1l lal IIIc. 4 . (i.e. TERRACING (T))
111 1 1 1 11 1 1 1-1 1- 1 _
1 I11I111111111111111lle
l-1l1-II11111111I "...
1 =1 I I-1 I I-1 1-111=1
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I -III -1I 1=111=1 BERM (B) (i.e. TERRACING (T))
1 I 1 1 I HI I 1-1 11=11I- s*; A!.....,.
l I 111-I I I-111 1 l .-1 l BERM (B)
li 111-11111_111-I .
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ih
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-
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r
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-
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, VEGETATED BUFFER (VB)
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WHEN IN PROXIMITY
TO STREAM
EROSION CONTROL
(i.e. RIPRAP (R))
LEGEND
11 i CUT SLOPE _
RIPRAP (R)
'.,ry, '' FILL SLOPE VEGETATED
SEDIMENT CONTROL OPTIONS EROSION CONTROL OPTIONS
.•••.-.• - BUFFER (VB)
CHECK DAM (CD) EROSION CONTROL BLANKET
FILTER BERM (FB) (ECB)
I 1 ROADSIDE DITCH (RSD)
SEDIMENT TRAP (ST) HYDRAULIC MULCHING (HM)
lb CHECK DAM (CD)
SILT FENCE (SF) MULCHING (M)
IEW— 1 DIVERSION (D) OR (ROD)
SEDIMENT TRAP (ST)
BERM %"*=`'
WATTLE (W) RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
(B) -
GROUND SURFACE
SURFACE ROUGHENING (SR)
TERRACING (T)
TOPSOIL STOCKPILE (TS) ------- ----' CONTOUR (BEFORE
WATTLE (W)
CONSTRUCTION)
EROSION CONTROL
BLANKET (ECB) I FLOW
WATTLE (W)
ENSR
NOT TO SCALE
AECOM
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
SITE PLAN
STEEP TERRAIN
DATE. 06/06/08 DRAM: E.S.S./GOL
FIGURE SP -2
File: M.• Encona l BMP Manuol i dwgs l ENC-BMPM SP -1 and Ds. DWG Layout: FIGURE 9-1 User: eschneider Plotted: Jun 09, 2008 - 1.58pm Xref "s.•
I PI 1 1 1 1 1
SEDIMENT CONTOL
(i.e. CHECK DAM (CD)) (TYP.)
,1,111
STABILIZED
CONSTRUCTION
ENTRANCE (SCE)
SLASH AND/OR
EROSION CONTROL
SEDIMENT CONTROL
(i.e. WATTLE(W)) (TYP.)
ur_
Ii
File: M.• Encona l BMP Manuol i dwgs l ENC-BMPM SP -1 and Ds. DWG Layout: FIGURE 9-2 User: eschneider Plotted: Jun 09, 2008 - 1.58pm Xref's:
SEDIMENT CONTROL
(i.e. CHECK DAM (CD))
EROSION CONTROL
(i.e. EROSION CONTROL BLANKET (ECB))
SEDIMENT CONTROL
(i.e. SEDIMENT TRAP (ST)
& CHECK DAM (CD))
(SD)
IF DISCHARGESLOPEDRAIN
IS ON STEEP SLOPES
EROSION CONTROL
IN FILL SLOPES
NEAR CULVERTS
SEDIMENT CONTROL OPTIONS
CHECK DAM (CD)
FILTER BERM (FB)
SEDIMENT TRAP (ST)
SILT FENCE (SF)
WATTLE (W)
EROSION CONTROL OPTIONS
EROSION CONTROL BLANKET
(ECB)
HYDRAULIC MULCHING (HM)
MULCHING (M)
RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
ACCESS ROAD INTERSECTION
WELL PAD ABOVE ROAD
DIVERSION (D)
BERM (B)
RUN ONI =1I ----_ _ _
DIVERSION (ROD)
CUT..�,�
I' LI
BERM (B)
� WELL PAD DETENTION
POND (DP)
EROSION CONTROL
—
(i.e. TERRACING (T))
EROSION CONTROL 1 lI I III 1 II= 11 11 III 4 _____
11
(i.e. TERRACING (T)) II 111 111111II 1 I I' III I � . I I III III I III 1I=1I 1 III 1 � 7 -----_____ __FILL
11 1111=1111 111=III I I1=III III—III EII 111= _____ -1
q � �� III -11 i 1= 1111 I S I—II I III=III III=III III,
—W-7-071!1111 i I I-111 DIVERSION (D)
le —IIIIII III -III III IIII III III HI' --' ,
FRAC OR DRILL PIT TOPSOIL STOCKPILE (SP)
WATTLE (W)
WIDE BERM (B) BERM (B)
rWITHIN ROADWAY
ROAD WELL PAD
CCESS
pAD AI
1I 111 111 II Ii=
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-_ ill—III III III= DIVERSION (D) WITH CH
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SEDIMENT RUN ON EROSION CONTROL
CONTROL DIVERSION (ROD) (i.e. WATTLE (W)) (TYP.)
(i.e. SEDIMENT
TRAP (ST)) (TYP.)
.
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_
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r PIT
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C is M
WELL HEADS i t •
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•
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FLOW DETENTION
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'
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`° RESERVOIR • ••••.,•
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:.SURFACE (SEDR) 03
WATER ' FILL SLOPE ,
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FLOW EROSION CONTROL' .
TOPSOIL STOCKPILE •d�b
(SP
WATTLE (W)'• )
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VEGETATED BUFFER ' i.e. WATTLE W =�1
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s..
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CONTROL OPTIONS EROSION CONTROL OPTIONS
EROSION CONTROL =
••... '.' ,'
•' et• w
=SEDIMENT
CHECK DAM (CD) EROSION CONTROL BLANKET
FILTER BERM (FB) (ECB)
SEDIMENT TRAP HYDRAULIC MULCHING
•. o.
GATHERING LINE i•
.rki r' a
_ _
,, i ,,,,..
(ST) (HM)
SILT FENCE (SF) MULCHING (M)
WATTLE (W) RETAINING WALL (RW)
NOT TO SCALE
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
ENSR
1 AECOM
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
WELL PAD
DATE: 06/06/08 DRWN: E.S.S./GOL
FIGURE D-3
SLASH AND/OR
EROSION CONTROL
WINDROW
ROADSIDE
DITCH (RSD)
EROSION CONTROL
(i.e. RIPRAP (R))
_ INSLOPE
-.116:60
1-111—1
ifil
II III III III III
-BACKFILL II—
I II II II ICUILVERTI(G)I IIV II II= II I I I I I I I I I IIII 1=1 ��11 STREAM
=l 1
1 111 111-11 1 1 1 1—III 1 11 1III IIIIII III 11 11 I_I I 11 111
1 1111 ;111 -III III=III-1 1 1 1 1 III III III I I I
GATHERING LINE 1—
iii—iii—ii
11 I—III I —III1 I III=IIII II I II IIII= III= I 1 I I—III I 111 111 111 111
_ —11 —1 H=1 i11=-111=111=111= III=111=_L== _ ___ _ ==111= _ __
=III=III=IIIIIIIII=III=III=III III I I I=I 11 I I I ,1 1111111
EROSION CONTROL
(i.e. RIPRAP (R))
VEGETATED
BUFFER (VB)
CUT
SLOPE
SEDIMENT CONTROL
_(i.e. SEDIMENT TRAP (ST))
EROSION CONTROL
(i.e. EROSION BLANKET (ECB) AND
REVEGETATION (RV))
LSURFACE
I WATER
FLOW
<SLASH AND OR EROSION CONTROL
INSLOPE
EROSION CONTROL
(i.e. RIPRAP (R))
CULVERT (C)
I I
:ice tiuffi-_"
CULVERT PROTECTION (CP)
.4111.
ROAD SLOPE
.•.' VEGETATED
.BUFFER (VB)
SLOPE DRAIN (SD) IF .'. . .
DISCHARGE IS ON •
STEEP SLOPES
.EROSION CONTROL.•.•.•
• ON STEEP SLOPES
EROSION CONTROL
(i.e. RIPRAP (R))
NOT TO SCALE
ENSR AECOM
SEDIMENT CONTROL OPTIONS
CHECK DAM (CD)
FILTER BERM (FB)
SEDIMENT TRAP (ST)
SILT FENCE (SF)
WATTLE (W)
EROSION CONTROL OPTIONS
EROSION CONTROL BLANKET
(ECB)
HYDRAULIC MULCHING (HM)
MULCHING (M)
RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
DATE 06/06/08
DRWN E.S.S.\GOL
ROAD PARALLEL TO
GATHERING LINE AND STREAM
1 FIGURE D-4
File: M d Encana l BMP Manual) dwgs l ENC-BMPM_SP-1 and Ds.DWG Layout:: FIGURE D-5 User: eschneider Plotted:: Jun 09, 2008 - 2.01pm Xref's:
EROSION CONTROL
(i.e. RIPRAP (R))
ROAD
1
1
FILL -
EROSION CONTROL ON
STEEP SLOPES
CONTROL
1-1,11 IliIII II1 II -%\(i EROSION
— — •
1I _III I I I I I I I I III III III III III III III III — ��•�
II 11
1-1I ll -ll
— III III III III III III ERT (C)
11 III—III III III III—III III III 1. CULV 111 III—III
=I 111=III III III 1 11 111111111111111 � 1 . l111=111 11111111111111111111 1 1
(i.e. RIPRAP (R))
SECTION VIEW
ROAD —i
PROFILE VIEW
40' MIN.
SLIGHT MOUND OVER CULVERT
CULVERT (C)
4-- ROAD
EROSION CONTROL (i.e. RIPRAP(R))
SEDIMENT CONTOL (i.e. CHECK DAM (CD)
OR SEDIMENT TRAP (ST))
ABOV FLOOD PLAIN
SURFACE
WATER
FLOW
ROADSIDE
DITCH (RSD)
i;
my_
RENiii_ .-
INSLOPE
m
D
1
EROSION CONTROL (i.e. EROSION CONTROL
BLANKET (ECB) AND WATTLES (W))
VEGETATED BUFFER (VB)
i
i
ROAD lV, 8%, —R
1UR1.4OVS
Nim
EROSION CONTROL
(i.e. RIPRAP (R))
CULVERT (C)
SURFACE
WATER
FLOW
ROADSIDE
DITCH (RSD)
•\ ROAO 8%)
_FtUCs�OPt SLOPE DRAIN (SD) IF•.
DISCHARGE IS ON
STEEP SLOPES,
L'A;N'0
7.•. .
VEGETATED
BUFFER (VB) ; .
NOT TO SCALE
ENSR AECOM
r
INSLOPE
EROSION CONTROL •,-,•.
-,(i.e. RIPRAP (R))
•�
EROSION CONTROL .
• ON STEEP SLOPES
SEDIMENT CONTROL OPTIONS
CHECK DAM (CD)
FILTER BERM (FB)
SEDIMENT TRAP (ST)
SILT FENCE (SF)
WATTLE (W)
EROSION CONTROL OPTIONS
EROSION CONTROL BLANKET
(ECB)
HYDRAULIC MULCHING (HM)
MULCHING (M)
RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
Storm Water Manual of
Best Management Practices
Encana, Parachute, Colorado
DATE: 06/06/08
DRWN: E.S.S./GOL
404 STREAM CROSSING
FIGURE D-5
STREAM
SEDIMENT CONTROL FLUME
(i.e. WATTLE (W))
VEGETATION BUFFER
SEDIMENT CONTROL
(i.e. WATTLE (W))
'•
TRENCH BREAKER (TB)
(LE. SAND BAGS)
GATHER NG LINE
RIGHT-OF-WAY
r0�
GATHERING LINE
III
Ell
NIII
E.
I■1
I
I
BillIII
TRENCH
TRENCH BREAKER (TB)
(i.e. SAND BAGS) (TYP.)
i--1
I
]i
vrv
1
TEMPORARY
_
BRIDGE
MOVABLE SEDIMENT CONTROL
(i.e. WATTLE W/ HANDLES)
VEGETATION BUFFER
MOVABLE SEDIMENT CONTROL
(i.e. WATTLE W/ HANDLES)
/
SEDIMENT CONTROL OPTIONS EROSION CONTROL OPTIONS
NOTE: AFTER TRENCH IS
BACK-FILLED, REVEGETATE
ENTIRE RIGHT-OF-WAY AND
COVER WITH SLASH AND/OR
OTHER EROSION CONTROL..
CHECK DAM (CD) EROSION CONTROL BLANKET
FILTER BERM (FB) (ECB)
SEDIMENT TRAP (ST) HYDRAULIC MULCHING (HM)
SILT FENCE (SF) MULCHING (M)
WATTLE (W) RETAINING WALL (RW)
REVEGETATION (RV)
RIPRAP (R)
SURFACE ROUGHENING (SR)
TERRACING (T)
WATTLE (W)
I
ENSR
NOT TO SCALE
1 AECOM
Storm Water Manual of
Best Management Practices
EncanParachute, Colorado
GATHERING LINE
(DURING CONSTRUCTIONCROSSING
CONDITION)
DATE: 06/06/08 DRWN E.S.S./GOL
FIGURE D-6
Erosion Control BMPs
Erosion Control Blanket (ECB)
Hydraulic Mulching (HM)
Land Grading (LG) — Roads
Low Water Crossing (LWC)
Mulching (M)
Retaining Wall (RW)
Revegetation (RV)
Riprap (R)
Soil Stabilizers (SS)
Stockpiling (SP) — Topsoil and Subsoil
Surface Roughening (SR)
Terracing (T)
Turf Reinforcement Mat (TRM)
Vegetated Buffer (VB)
Wattles (W)
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM
Final 06-09-08.doc
June 2008
Erosion Control Blanket (ECB)
Description
Erosion control blankets are porous fabrics and are manufactured by weaving or bonding fibers made from
organic or synthetic materials. Erosion control blankets are installed on steep slopes, over berms, or in
channels to prevent erosion until final vegetation is established. However, blankets can also be used as
separators or to aid in plant growth by holding seeds, fertilizers, and topsoil in place.
Applicability
Erosion control blankets may be used in the following applications:
• To control erosion on steep slopes and to promote the establishment of vegetation.
• To stabilize channels against erosion from concentrated flows.
• To protect berms and diversions prior to the establishment of vegetation.
• To protect exposed soils immediately and temporarily, such as when active piles of soil are left
overnight.
• As a separator between riprap and soil to prevent soil from being eroded from beneath the riprap
and to maintain the riprap's base.
• May be used on slopes as steep as 1:1.
Limitations
• Blankets used on slopes should be biodegradable, or photodegradable, non-toxic to vegetation or
germination of seed, and non-toxic or injurious to humans.
• Should not be used on slopes where vegetation is already established.
• Some blankets might promote increased runoff and might blow away if not firmly anchored.
• If the fabric is not properly selected, designed, or installed, the effectiveness may be reduced
drastically. Manufacturer's specifications should be followed.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM
Final 06-09-08.doc
ECB -1
June 2008
Design criteria
There are many types of erosion control blankets available. Therefore, the selected fabric should match its
purpose. Effective netting and matting require firm, continuous contact between the materials and the soil. If
there is no contact, the material will not hold the soil, and erosion will occur underneath the material. Fabric
should be purchased at an appropriate with to cover the whole width of the channel, if possible. Table ECB -1
indicates some recommended criteria for the selection of erosion control blankets.
Construction specifications
1. Smooth soil prior to installation and apply seed prior to fabric installation for stabilization of
construction sites.
2. Select the appropriate fabric type. North American Green products are listed in Table ECB -1.
However, other products may also be used. Site specifics shall dictate blanket selection and use.
3. Select the appropriate seed mix according to the specification in Revegetation (RV).
4. Installation of the blankets shall be in accordance with the manufacturer's recommendations and
according to Figure ECB -1. For blankets being placed in channels, the fabric should be rolled out
parallel to the channel if the width is sufficient to cover the entire width of the channel. The fabric
needs to be in continuous contact with exposed soil.
5. Pins or staples shall be made of wire 0.162 inch or larger in diameter. "U" shaped staples shall
have legs 8" long, and a 1" crown. "T" shaped pins shall have a minimum length of 8". The bar of
the "T" shall be at least 4" long. Triangular survey stakes can also be used.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspections
should determine if cracks, tears, or breaches have formed in the fabric. If the effectiveness of the BMP has
been reduced, the fabric should be repaired or replaced immediately. Re -anchor loosened matting and
replace missing matting and staples as required. It is necessary to maintain contact between the ground and
the blanket at all times. Trapped sediment should be removed after each storm event.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
North American Green, 2004. <http://www.nagreen.com>
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ECB -2
June 2008
Table ECB -1
Suggested Blanket Types
Description (North
American Green Product #)
Longevity
Applications
Max. Flow
Velocity (feet/sec.)
Single Net Straw Blanket
(S75)
12 months
4:1 - 3:1 Slopes
Low Flow Channels
5
Rapid Degrading Net (DS75)
45 - 60 Days
Double Net Straw Blanket
(S150)
12 months
3:1 - 2:1 Slopes
Moderate Flow Channels
6
Rapid Degrading Nets
(DS150)
45 - 60 Days
Double Net Blanket
70% Straw/30% Coconut
(SC150)
24 months
2:1 - 1:1 Slopes
Medium Flow Channels
8
Double Net Blanket
100% Coconut (C125)
36 months
1:1 & Greater Slopes
High Flow Channels
10
Double Net Blanket
Polypropylene Fiber (P300)
1:1 Slopes
Extended Flow Areas
High Flow Channels
9 (unveg.)
16 (veg.)
Organic Net (S75BN)
12 months
4:1 - 3:1 Slopes
Low Flow Channels
5
Organic Net (S150BN)
12 months
3:1 - 2:1 Slopes
Moderate Flow Channels
6
Organic Net (SC150BN)
18 months
2:1 - 1:1 Slopes
Medium Flow Channels
8
Organic Net (C125BN)
24 months
1:1 &Greater Slopes
High Flow Channels
10
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ECB -3
June 2008
Figure ECB -1
Erosion Control Blanket Installation
13ury upsluptn rmd of bL]nkel in
trench 6- deep by 6- .ick+
9lanr[axC
Use a b' rrr`. overlay whemwtr %mu
maths of blarlel are applied side
by arida.
8laple pallet Mini ntrn 3 pet
sduare yard.
Flaw
fabric
anchored 11 trench
Use a 8' overlap wFletearer ohne NA
3 et Wankel*VS end anoi* b >,*.
pari fabnc
anchcxeid in trench
Cher.* skits should be [rase every 18'. Insert a Fuld Or the blanket
arta a trench 6" wile by 6' deep and lanilpfirmly Lay the blanket
smoothly ash the surface or the sod. Do not stretch the bletlkeL end
do nr.g allow wrinkles. Instal slap40 20' On Cerner in Irerdi.
15' 1.1 at
4-
irpoasi<sks. purchase tfankel with a3 Width that its
ureic entaugh to reach all the way:m=44 the
Channel, Plaut Nankai parellrl td the direcGar,
flow. Gro rant join strops in lie ceased' dick
Lisa chock slots as rO141mnd.
NOT TO SCALE
L fabr
anehorod in trench
,...-.. .. ilii
llr�ii 1�1�1=1Fi�l�r,
�IWal�al�nlzirylt�.l
aillill�l`al�ll
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ECB -4
Baanrel fatarrr,
anchored in trench
Placr~ Market parallrl Fir., Ikr
dteciion all Flow and anchor
securely. 'firing blanket to a
Igan-1 arra br.4nm inrrninatrog
the Installahor
-Y_
June 2008
Hydraulic Mulching (HM)
Description
Hydraulic mulching (hydro -mulching) is a temporary erosion control practice in which materials such as grass,
hay, wood chips, wood fibers, straw, or gravel are hydraulically applied to exposed or recently planted soil
surfaces. Hydraulic mulching stabilizes soils by minimizing rainfall impact and reducing stormwater runoff
velocity. When used in combination with seeding or planting, hydraulic mulching can aid plant growth by
holding seeds, fertilizers, and topsoil in place, preventing birds from eating seeds, retaining moisture, and
insulating plant roots against extreme temperatures.
Hydraulic application of mulch (as well as seed) can be done quickly and efficiently with the correct equipment
and ingredients.
Applicability
Hydraulic mulching is often used in steep areas where regular mulching is difficult because of environmental
constraints. Hydraulic mulches can be used on seeded and planted areas where slopes are as steep as 1:1.
Limitations
• Hydro -mulching might delay seed germination because the cover changes soil surface temperatures.
• The mulch itself is subject to erosion and may be washed away in a large storm.
• Maintenance is necessary to ensure that hydro -mulch provides effective erosion control.
• Hydraulic application of mulch must be done when no rainfall is expected, preferably within a 24-hour
time period.
Design criteria
No formal design is required.
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HM -1
June 2008
Construction specifications
1. Site preparation:
a. Prior to mulching, install the necessary temporary or permanent erosion control practices and
drainage systems within or adjacent to the area to be mulched.
b. Slope, grade, and smooth the site to fit needs of selected mulch products.
c. Remove all undesirable stones and other debris to meet the needs of the anticipated land use and
maintenance required.
2. Hydraulic mulching:
a. For steep slopes an Erosion Control Mulch (ECM) consisting of a hydraulic matrix such as a
Bonded Fiber Matrix (BFM) or Flexible Growth Medium (FGM) may be used. A BFM refers to a
continuous layer of elongated wood fiber strands that are held together by a water-resistant
bonding agent to form a water -absorbing crust.
b. The ECM shall be a hydraulically -applied, flexible erosion control blanket composed of long
strand, thermally refined wood fibers, crimped, interlocking fibers, and performance enhancing
additives. The ECM shall require no curing time period and upon application shall form an
intimate bond with the soil surface to create a continuous, porous, absorbent and erosion resistant
blanket that allows for rapid germination and accelerated plant growth.
c. The ECM shall conform to the property values in Table HM -1 when uniformly applied at a rate of
3500 pounds per acre (3900 kilograms/hectare) under laboratory conditions. Composition shall
be as follows:
Thermally Processed Wood Fibers: 74.5% ± 2.5%
Crosslinked Hydro -Colloid Tackifier: 10% ± 1%
Crimped, Interlocking Fibers: 5% ± 1%
Moisture Content: 10.5% ± 1.5%
3. Installation:
a. Strictly comply with manufacturer's installation instructions and recommendations. Use approved
hydro -spraying machines with fan -type nozzle (50 -degree tip) whenever possible to achieve best
soil coverage. Apply ECM from opposing directions to soil surface to assure 95% soil surface
coverage. Slope interruption devices or water diversion techniques are recommended when slope
lengths exceed 100 ft (30m).
b. Step One: Apply seed, fertilizer and other soil amendments with tackifier and a small amount of
ECM for visual metering (see Revegetation (RV) for application rates).
c. Step Two: Mix 50 Ib of ECM per 125 gallons (23 kg/475 liters) of water; confirm loading rates with
equipment manufacturer (different manufacturers rates may vary slightly).
d. Install materials at the typical application rates in Table HM -2.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Areas should
be identified where mulch has loosened or been removed. Such areas should be reseeded (if necessary) and
the mulch cover replaced. If washout, breakage, or erosion occurs, surfaces should be repaired, reseeded,
and re -mulched. Inspections should be continued until vegetation is firmly established.
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HM -2
June 2008
References
California Stormwater Quality Association, Stormwater Best Management Practice (BMP) Handbook —
Construction. January, 2003. <http://www.cabmphandbooks.com/Construction.asp>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Table HM -1
Property Values for Erosion Control Mulch
Property
Test Method'
English
SI
Physical
Mass Per Unit Area
ASTM D-6566
11.5 oz/yd2
390 g/m2
Thickness
ASTM D-6525
0.19 in
4.8 mm
% Ground Cover
ASTM D-6567
99%
99%
Flexural Rigidity (wet)
ASTM D-6575
0.138 oz -in
10,000 mg -cm
Color (fugitive dye)
Observed
Green
Green
Endurance
Functional Longevity
Observed
Up to 18 months
Up to 18 months
Performance
Cover Factor3 (6 in/hr event)
ECTC Test Method #2
0.0066
0.0066
% Effectiveness3
ECTC Test Method #2
99.34%
99.34%
Shear Stress
ECTC Test Method #3
1 Ib/ft2
48 Pa
Vegetation Establishment
ECTC Test Method #4
800%
800%
1. ASTM and ECTC (Erosion Control Technology Council) test methods developed for Rolled Erosion Control Products.
2. Cover Factor is calculated as soil loss ratio of treated surface versus an untreated control surface.
3. % Effectiveness = 1 minus Cover Factor multiplied by 100%.
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HM -3
June 2008
Table HM -2
Typical Mulch Application Rates
Slope Gradient/Condition
English
SI
<3H to 1V
3000 Ib/ac
3400 kg/ha
>3H to 1V and <2H to 1V
3500 Ib/ac
3900 kg/ha
>2H to 1V and <1H to 1V
4000 Ib/ac
4500 kg/ha
>1H to 1V
4500 Ib/ac
5100 kg/ha
Below ECB or TRM
1500 Ib/ac
1700 kg/ha
As infill for TRM
3500 Ib/ac
3900 kg/ha
Slope Gradient/Condition
Performance Specification
<3H
—
70-80% soil coverage,
minimum 0.16 inch depth
<3H to 1V
—
90-100% soil coverage, <2" rocks uncovered,
minimum 0.19 inch depth
>3H to 1V and <2H to 1V
95-100% soil coverage, <6" rocks uncovered,
minimum 0.22 inch depth
>2H to 1V and <1H to 1V
100% soil coverage, <12" boulders uncovered,
minimum 0.22 inch depth
>1H to 1V
All exposed surfaces including rock outcrops shall be
covered at a minimum of 0.24 inch depth
Below ECB or TRM
1500-2500 Ib/ac slope dependent, minimum 0.08 inch
depth
As infill for ECB
1500-3500 Ib/ac, minimum 0.19 inch depth
As infill for TRM
Perpendicular application with 100% infill,
minimum 0.19 inch depth
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HM -4
June 2008
Land Grading (LG) — Roads
Description
Land grading of roads involves reshaping the ground surface to planned grades as determined by an
engineering survey, evaluation, and layout. This BMP shall include the following:
• Proper road cut and fill techniques to ensure road remains stable over time.
• Road crowning or sloping to properly route runoff off the roadway.
• Surfacing the road with gravel to avoid mud, rutting, and large quantities of sediment that will wash
away during storms.
Applicability
• This BMP is applicable to the construction and maintenance of any road, but particularly those located
on steep topography or easily erodible soils.
• Road gravel is applicable to all roads with "soft" sections, steep grades, highly erosive soils, or where
all-weather access is needed. Road gravel may be used as "fill" material in ruts or as a full structural
section over the entire road.
Limitations
• Improper cut and fill slopes that disrupt natural stormwater patterns might lead to poor drainage, high
runoff velocities, and increased peak flows during storm events.
• Rutting and washboarding may develop if surface gravel is not designed properly or if road is not
sloped.
• Flat-blading to maintain the roadway must be done properly to avoid changes in gravel thickness, road
slope, and road grade.
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LG -1
June 2008
Design criteria
Grading plan
A grading plan should be prepared that establishes the extent to which the road will be graded, how drainage
patterns will be directed, and how runoff velocities will affect receiving waters. The grading plan also includes
information regarding when earthwork will start and stop, establishes the degree and length of finished slopes,
and dictates where and how excess material will be disposed of (or where borrow materials will be obtained if
needed). Practices must be developed for erosion control, slope stabilization, and safe disposal of runoff
water and drainage, such as ditches and culverts, grade stabilization structures, retaining walls, and surface
drains. Berms, roadside ditches, and other stormwater practices that require excavation and filling also should
be incorporated into the grading plan.
Slope failures
Landslides and failed road cuts and fills can be a major source of sediment, they can close the road or require
major repairs, and they can greatly increase road maintenance costs. Slope failures, or landslides, typically
occur where a slope is over -steep, where fill material is not compacted, or where cuts in natural soils
encounter groundwater or zones of weak material. Good road location can often avoid landslide areas and
reduce slope failures. When failures do occur, the slide area should be stabilized by removing the slide
material, flattening the slope, adding drainage, or using structures, as discussed below. Designs are typically
site specific and may require input from geotechnical engineers and engineering geologists. Failures that
occur typically impact road operations and can be costly to repair. Failures near streams and channel
crossings have an added risk of impact to water quality.
Road slope
See Figure LG -1. All roads should be designed with one of the following three slope types:
• Outsloped roads minimize the concentration of water and minimize road width by avoiding the need
for an inside ditch, but may require roadway surface and fill slope stabilization. Outsloped roads with
clay rich, slippery road surface materials often require surface stabilization with gravel or limited use
during rainy periods to assure traffic safety. On road grades over 10 to 12 percent and on steep hill
slope areas, outsloped roads are difficult to drain and can feel unsafe.
• Insloped roads are the best method to control surface water. However, insloped roads also
concentrate water and require a system of ditches and turnouts or cross -draining culverts.
• Crowned roads are appropriate for higher standard, two lane roads on gentle grades. They may or
may not require roadside ditches, turnouts, and/or cross -drains. It is difficult to create and maintain a
crown on a narrow road, so generally insloped or outsloped road drainage is more effective.
Construction specifications
Cut and fill slopes
1. All applicable perimeter erosion and sediment control practices and measures (berms, diversions,
silt fence, vegetated buffer, or wattles) shall be constructed prior to any road grading activities,
and maintained in accordance with this BMP and the Stormwater Management Plan (SWMP).
Perimeter controls should remain in place until all graded or disturbed areas, including slopes, are
adequately stabilized.
2. All areas to be disturbed (both cut and fill) shall be cleared, grubbed, and stripped of topsoil to
remove trees, vegetation, roots, or other objectionable material.
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LG -2
June 2008
3. Fill material shall be free of brush, logs, stumps, roots, or other objectionable materials that would
interfere with, or prevent, construction of satisfactory fills. This material can be set aside and later
used at the toe of fill slopes as filter berms. Frozen material shall not be placed in the fill nor shall
the fill material be placed on a frozen foundation.
4. Table LG -1 presents a range of commonly used cut and fill slope ratios appropriate for the soil
and rock types described. Figures LG -2 and LG -3 present typical cut slope and fill slope design
options for varying slope and site conditions. Vertical cut slopes should not be used unless the
cut is in rock or very well cemented soil. Ideally, both cut and fill slopes should be constructed
with a 2:1 or flatter slope to promote growth of vegetation, but cut slopes in dense, sterile soils or
rocky material are often difficult to vegetate.
5. All fills shall be compacted as required to reduce erosion, slippage, settlement, subsidence, or
other related problems.
6. Topsoil required for the establishment of vegetation shall be stockpiled in the amount necessary to
complete finished grading of all exposed areas. Areas that are to be topsoiled shall be scarified to
a minimum depth of 4 inches prior to placement of topsoil.
7. Terraces or contour trenches (see Terracing (T)) shall be provided whenever the vertical interval
(height) of any 2:1 cut or fill slope exceeds 20 feet; for 3:1 slope it shall be increased to 30 feet
and for 4:1 to 40 feet.
8. All graded cut and fill areas shall be stabilized, either structurally or vegetatively, immediately
following finished grading. Some common slope stabilization options appropriate for roads
include hydroseeding, hydromulching, erosion control blankets, riprap, and retaining walls.
Road slope
1. See Figure LG -1. Compact soil or road base material to direct runoff.
2. If crowning a road, runoff is directed to both sides of the road requiring two roadside ditches,
unless runoff will drain directly to well stabilized areas.
3. If using an inslope design, runoff is directed toward the hillside and requires a roadside ditch with
periodic turnouts or cross drain culvert installation.
4. If using an outslope design, ensure a moderate road slope with dense vegetative cover.
Surface gravel
1. Gradation of gravel should be according to Figure LG -4. This figure shows the typical gradation
ranges of aggregates used in road construction, how the materials, ranging from coarse to fine,
best perform for a road, and the approximate limitations to the desirable gradation ranges. Ideally,
aggregate surfacing material is (1) hard, durable, and crushed or screened to a minus 2 -inch size;
(2) well graded to achieve maximum density; (3) contains 5-15% clayey binder to prevent raveling;
and (4) has a Plasticity Index of 2 to 10.
2. Gravel should be placed to a thickness of at least twice the diameter of the largest stone with a
minimum thickness of 4 inches. Over very weak soils gravel thickness can be reduced with the
use of geotextile or geogrid subgrade reinforcement. Also, geotextile layers are useful over soft
soils to separate the gravel from the soil, keep it uncontaminated, and extend the useful life of the
gravel.
3. Compact the aggregate during construction and maintenance to achieve a dense, smooth road
surface and thus reduce the amount of water that can soak into the road.
4. "Spot" stabilize local wet areas and soft areas with 4 to 6 inches of coarse rocky material. Add
more rock as needed.
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LG -3
June 2008
5. Blend coarse aggregate and fine clay -rich soil (when available) to produce a desirable composite
roadway material that is coarse yet well -graded with 5-15% fines for binder.
Maintenance considerations
The frequency of inspections should be in accordance with the SWMP. Inspect cut and fill slopes for rills or
other indications of erosion. Maintain all crowns, outslopes, inslopes, and surface gravel.
The road surface and shoulders should be periodically smoothed and reshaped with a grader blade (flat-
blading). This should be done when the gravel is moist. Maintain the proper road slope and grade while flat-
blading. Also be sure to avoid plugging roadside ditches or altering adjacent drainage structures, as this may
cause them to not function properly. Flat-blading may also cause road gravel to be pushed off the main
roadway and onto the shoulders. To avoid this, blade toward the center of the road.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://wvvw.dec.state.ny.us/website/dow/toolbox/escstandards>
United States Department of the Interior and United States Department of Agriculture. Surface Operating
Standards and Guidelines for Oil and Gas Exploration and Development "Gold Book." BLM/WO/ST-
06/021+3071. Bureau of Land Management (BLM). Denver, Colorado. Fourth Edition, 2006.
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LG -4
June 2008
Table LG -1
Stable Slope Ratios for Various Conditions
Soil/Rock Condition
Slope Ratio
(Hor:Vert)
Most rock
'/4:1 to '/2:1
Very well cemented soils
1/4:1 to 1/2:1
Most in-place soils
3/4:1 to 1:1
Very fractured rock
1:1 to 1 1/2: 1
Loose coarse granular soils
1 1/2: 1
Heavy clay soils
2:1 to 3:1
Soft clay rich zones or wet
seepage areas
2:1 to 3:1
Fills of most soils
1 1/2:1 to 2:1
Fills of hard, angular rock
1 1/3 :1
Low cuts and fills
(<10 ft high)
2:1 or flatter
(for revegetation)
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LG -5
June 2008
FILTER BERM
:JR OTHER
SEDIMENT
CONTROL ,,_
Figure LG -1
Typical Road Surface Drainage Options
Crown Section
Outslope Section
2 lyp.
1I—
5-5%
Irtslope with Ditch Section
1p --- —.—'�►
NOT TO SCALE
a_ Balanced Cut and Eli
Use a Balanced Cul and SII
Section for Moral cOnSlinidinn
on Hill slopes
Roadside Bich itypp.b
Road
y� k
FIll
ROADSIDE DITCI-1
Figure LG -2
Cut Slope Design Options
b. Full nen Ji
Ground Surface
Col
Typical Cut slopes in
Most Soils 1:1 lo 1:1
Finer Berm dr -00W S+irngnl Comm!
0-60% Ground Slopes
c. Through Cul
Road —
Ground Surface
Low Cut Can his Steepcx Rater
0 Ground Slopes
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM
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.4 k
Iligh Cul Typical
Sleeper Mere Statile
LG -6
1 'Fp.
11
Typical Cut dopes II
Meat's aL 1 to 1.1
Ty{sieal cath
Cel Slovras •
p_1 to ;!9
Road
Use Full Bench Guts When 1Fre
Ground elopes Exceed PUG%
50%+ Ground Slopes
NOT TO SCALE
June 2008
a. Tryis!col FNI
Note. Side-c1lill material arty
slqrsas. eisey from strzwriE
b. Bianchd Slope Fill
with L35013( Piecemeal
On ground where slcoes exceed
.10-4.V14, iecirininel bid-,r...A I 11)
elde0 ele enough ice
esatimilliOa and cenviettion
equipment
c. Reinforced FIN
Figure LG -3
Fill Slope Design Options
Roadside Mb ltygg
Rood
FiIIr Bann or Other
Sediment Conlrol (tm )
•Scarify end rernoso
organic material
Cr:Met:1.50.W
0-40% Ground Slopes
Ground SU rface
Road
10,80% Grtimicl Slopes
Fill mold:mini i layrs- Lien
It or 5 to 12 In. Mick Gorioaa:
to spwilisid clarisityn ihml rcM
oac-ri leyer
'Ground Surface
Heinlorced fits ore used on sleep
gm:urethan SIM ;Remain* lu relairmr.9
Structures. The 1:1 (oversleep) face
usually riNuipes slablicatium.
d. Through Fill
NOT TO Sit -.A1 F
Lang
Road
slime 2:1
M:\Encana\BMP Manual \BMP Manual - Round 2\SWMM
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Shari
Slope 3:1
-Ground Surface
4-413% GrOurs121101101
LG -7
June 2008
a.x
143
Figure LG -4
Gradation and Performance of
Roadway Surfacing Materials
4tQu In Inch..
S1EYE ,Ah1ILY5I5
MYibW kI.S- 1'ly
AME 5IZ[ 111 1101U.11AtT119RL
NOTE: Gradation Rsngcc Shown Are Approximate.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM
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LG -8
June 2008
Mill_
NIS
.A
_
i0
iiiirdis
iori.
MI
'111
%iiLiIi'
Milli
Milli
ir.,,
l
'f. i�i
I�
Jy
i
�
,1„
..
ij�
rIJ
�
1
__I
!ii
j,
1„:%
IRM
Mill
.I
,cott,,,,,t,„
iii
'4..4.
-+i
Ilk
tt
-lri1111
1111
II i_s ie
AME 5IZ[ 111 1101U.11AtT119RL
NOTE: Gradation Rsngcc Shown Are Approximate.
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LG -8
June 2008
Low Water Crossing (LWC)
Description
A low water crossing is a temporary structure erected to provide a safe and stable way for construction vehicle
traffic to cross waterways. The primary purpose of such a structure is to provide streambank stabilization,
reduce the risk of damaging the streambed or channel, and reduce the risk of sediment loading from
construction traffic. A low water crossing may be a bridge, a culvert, or a ford surfaced with gravel, rip rap, or
concrete.
Applicability
Low water crossings may be used for the following applications:
• Wherever heavy construction equipment must be moved from one side of a stream channel to the
other, or where lighter construction vehicles will cross the stream a number of times during the
construction period.
• Bridges are ideal to pass the year-round flows associated with perennial drainages.
• Vented fords can be used to pass drainages with low flows and keep vehicles out of the water,
avoiding water quality degradation.
• Fords can be designed as a broadcrested weir in order to pass larger flow.
• Fords can be "forgiving" and accommodate uncertainties in the design flow and thus are ideal for
ephemeral and intermittent drainages with unknown or variable flow characteristics.
Limitations
• Low-water crossings that are not surfaced should not be used in wet conditions.
• Installation may require dewatering or temporary diversion of the stream.
• Bridges can be a safety hazard if not properly designed and constructed. Bridges might also prove to
be more costly in terms of repair costs and lost construction time if they are washed out or collapse.
• The construction and removal of culverts are usually very disturbing to the surrounding area and
erosion and downstream movement of soils is often great.
• The approaches to fords often have high erosion potential. In addition, excavation of the streambed
and approach to lay riprap or other stabilization material causes major stream disturbance. Mud and
other debris are transported directly into the stream unless the crossing is used only during periods of
low flow.
• Ford -type structures may imply some periodic or occasional traffic delays during periods of high flow.
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June 2008
Design Criteria
Site location
Locate the crossing where there will be the least disturbance to the soils of the existing waterway banks.
When possible, locate the crossing at a point receiving minimal surface runoff.
Elimination of fish migration barriers
Bridges pose the least potential for creating barriers to aquatic migration. The construction of any specific
crossing method shall not cause a significant water level difference between the upstream and downstream
water surface elevations.
Crossing alignment
Where possible, the low water crossing shall be at right angles to the stream.
Road approaches
The centerline of both roadway approaches shall coincide with the crossing alignment centerline for a
minimum distance of 50 feet from each bank of the waterway being crossed. If physical or right-of-way
restraints preclude the 50 feet minimum, a shorter distance may be provided. All fill materials associated with
the roadway approach shall be limited to a maximum height of 2 feet above the existing flood plain elevation.
Bridges
Over -stream bridges are generally the preferred low water crossing structure. The expected load and
frequency of the stream crossing, however, will govern the selection of a bridge as the correct choice for a
temporary stream crossing. Bridges usually cause minimal disturbance to a stream's banks and cause the
least obstruction to stream flow and fish migration. They should be constructed only under the supervision and
approval of a qualified engineer.
Culverts
Temporary culverts are used where a) streams are perennial or intermittent, b) the channel is too wide for
normal bridge construction, or c) anticipated loading may prove unsafe for single span bridges. Culverts are
normally preferred over a ford type of crossing, since disturbance to the waterway is only during construction
and removal of the culvert.
Fords
Fords are appropriate in steep areas subject to flash flooding, where normal flow is shallow or intermittent
across a wide channel. Fords should be used for crossing seasonally dry streambeds (ephemeral or
intermittent drainages) or streams with low flows during most periods of road use. Use fords in place of
culverts when there is a high possibility of plugging by debris or vegetation. Use improved (vented) fords with
pipes or concrete box culverts to pass low water flows and keep vehicles out of the water.
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June 2008
Construction specifications
Bridges
See Figure LWC-1.
1. Clearing and excavation of the stream shores and bed should be kept to a minimum.
2. A temporary bridge structure shall be constructed at or above bank elevation to prevent the
entrapment of floating materials and debris.
3. Abutments should be parallel to the stream and on stable banks.
4. If the crossing is to extend across a channel wider than 8 feet (as measured from top of bank to top of
bank), the bridge should be designed with one in -water support for each 8 feet of stream width. No
footing, pier, or bridge support will be permitted within the channel for waterways less than 8 feet wide.
5. Stringers shall either be logs, saw timber, pre -stressed concrete beams, metal beams, or other
approved materials.
6. Decking shall be of sufficient strength to support the anticipated load. All decking members shall be
placed perpendicular to the stringers, butted tightly, and securely fastened to the stringers. Decking
materials must be butted tightly to prevent any soil material tracked onto the bridge from falling into the
waterway below.
7. Run planking (optional) shall be securely fastened to the length of the span. One run plank shall be
provided for each track of the equipment wheels. Although run planks are optional, they may be
necessary to properly distribute loads.
8. Curbs or fenders may be installed along the outer sides of the deck. Curbs or fenders are an option,
which will provide additional safety.
9. Bridges shall be securely anchored at only one end using steel cable or chain. Anchoring at only one
end will prevent channel obstruction in the event that floodwaters float the bridge. Acceptable anchors
are large trees, large boulders, or driven steel anchors. Anchoring shall be sufficient to prevent the
bridge from floating downstream and possibly causing an obstruction to the flow.
10. All areas disturbed during installation shall be stabilized in accordance with Revegetation (RV).
Culverts
See Culvert (C).
Fords
See Figure LWC-2.
1. Locate fords where stream banks are low and where the channel is well confined.
2. Clearing and excavation of the stream shores and bed should be kept to a minimum.
3. Excavate streambed as necessary and place an 18 -inch thick layer of 4 -inch to 8 -inch riprap. Cover
this layer of riprap with a 6 inch thick layer of 2 inch to 4 inch crushed aggregate. The total thickness
of riprap/aggregate should be a minimum of 24 inches thick. This type of simple low water crossing is
ideal for ephemeral drainages.
4. For all approach roads the cut banks shall be no steeper than 5:1. The road approach shall be a
minimum distance of 50 feet from each bank. Spoil material from the banks shall be stored out of the
floodplain and stabilized.
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June 2008
5. Use an adequately long aggregate surface to protect the "wetted perimeter" of the natural flow
channel. Add protection above the expected level of the high flow. Allow for some freeboard, typically
a minimum of 12 inches in elevation, between the top of the reinforced driving surface and the
expected high water level.
6. The downstream edge of a ford is a particularly critical location for scour and may need energy
dissipaters or riprap protection.
7. Use well-placed, sturdy depth markers at fords to advise traffic of dangerous water depths.
8. All areas disturbed during ford installation shall be stabilized in accordance with Revegetation (RV).
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan.
Bridges
Inspection shall ensure that the bridge, streambed, and streambanks are maintained and not damaged. If any
structural damage is reported, construction traffic should stop use of the structure until appropriate repairs are
made. Evidence of streambank erosion should be repaired immediately. Any trapped sediment or debris shall
be removed and disposed of outside of the floodplain and stabilized.
Culverts
Inspection shall ensure that the culverts, streambed, and streambanks are not damaged, and that sediment is
not entering the stream or blocking fish passage or migration. Evidence of structural or streambank erosion
should be repaired immediately. Any trapped sediment or debris shall be removed and disposal of outside of
the floodplain and stabilized.
Fords
Inspections shall ensure that stabilization material (aggregate) remains in place. If the material has moved
downstream during periods of peak flow, the lost material should be replaced immediately.
Removal
All low water crossings shall be removed when the structure is no longer needed.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/storamater/menuofbmps/con_site.cfm>
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
United States Department of the Interior, Bureau of Land Management (BLM), United States Department of
Agriculture (USDA), Forest Service, Surface Operating Standards for Oil and Gas Exploration and
Development "Gold Book". Fourth Edition, 2005.
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June 2008
Sdririgers
NOT TO SCALE
Thri
24"
Figure LWC-1
Bridge Installation
A1nj1iriin1 'IIM
StatAlze4 B nk5
RD' min. Road afphyach
1?robrboald
1r min.
Abubnerile
Docking
Curbs
Figure LWC-2
Ford Installation
Traxr: F, .
N.es o1 s troarn bod
W min RgAd P{penaach
maxi -num 4Kp S.N.(1
WO water llesael
Ahreaniach
F
- Y
Crashed kggrogaie (2' -4 dia.)
NOT TO SCALE
Amirmaile e+,.)
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June 2008
Mulching (M)
Description
Mulching is a temporary erosion control practice in which materials such as grass, hay, wood chips, wood
fibers, straw, or gravel are placed on exposed or recently planted soil surfaces. Mulching stabilizes soils by
minimizing rainfall impact and reducing stormwater runoff velocity. When used in combination with seeding or
planting, mulching can aid plant growth by holding seeds, fertilizers, and topsoil in place, preventing birds from
eating seeds, retaining moisture, and insulating plant roots against extreme temperatures.
Mulch mattings are materials such as jute or other wood fibers that are formed into sheets and are more stable
than loose mulch. Jute and other wood fibers, plastic, paper, or cotton can be used individually or combined
into mats to hold mulch to the ground. Netting can be used to stabilize soils while plants are growing, although
netting does not retain moisture or insulate against extreme temperatures. Mulch binders consist of asphalt or
synthetic materials that are sometimes used instead of netting to bind loose mulches.
Hydraulic mulching is a temporary erosion control practice in which materials such as grass, hay, wood chips,
wood fibers, straw, or gravel are hydraulically applied to exposed or recently planted soil surfaces. See
Hydraulic Mulching (HM) for details.
Applicability
Mulching is often used in areas where temporary seeding cannot be used because of environmental
constraints. On steep slopes and critical areas such as waterways, mulch matting is used with netting or
anchoring to hold it in place. Mulches can be used on seeded and planted areas where slopes are steeper
than 2:1 or where sensitive seedlings require insulation from extreme temperatures or moisture retention.
Mulch is most effective when used on an area less than 2 acres in size and can last for 1 to 2 years.
Limitations
• Mulching, matting, and netting might delay seed germination because the cover changes soil surface
temperatures.
• The mulches themselves are subject to erosion and may be washed away in a large storm.
• Maintenance is necessary to ensure that mulches provide effective erosion control.
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June 2008
Design criteria
No formal design is required.
Construction specifications
1. Site preparation:
a. Prior to mulching, install the necessary temporary or permanent erosion control practices and
drainage systems within or adjacent to the area to be mulched.
b. Slope, grade, and smooth the site to fit needs of selected mulch products.
c. Remove all undesirable stones and other debris to meet the needs of the anticipated land use and
maintenance required.
2. Mulching & anchoring for relatively flat slopes:
a. Select the appropriate mulch and application rate that will best meet the need and availability of
material. When possible, organic mulches should be used for erosion control and plant material
establishment. See Table M-1 for suggested materials and application rates. Other materials
include hydraulic mulch products with 100 -percent post -consumer paper content and yard
trimming composts. All materials should be free of weed and seed.
b. Apply mulch immediately after soil amendments and planting is accomplished or simultaneously if
hydroseeding is used. See Table M-1 for installation guidelines.
c. Mulch before seeding if construction of restoration activity is interrupted for extended periods,
such as when seeding cannot be completed due to seeding period restrictions. If mulching before
seeding, increase mulch rate. Of application on all slopes within 100 feet of waterbodies and
wetlands.
d. Use a mulch crimper to apply and anchor mulch. Crimper should have approximately 6 inch
cleats with perpendicular, dull, disc blades. If a crimper is unavailable the Contractor shall apply
mulch and anchor it to the soil using one of the methods described in Table M-2. The mulch
should be anchored the same day as mulch application. Materials that are heavy enough to stay
in place (for example, bark or wood chips on flat slopes) do not need anchoring. Mulches may or
may not require a binder, netting, or tacking. Mulch binders should be applied at rates
recommended by the manufacturer. Effective use of netting and matting material requires firm,
continuous contact between the materials and the soil.
3. Hydraulic mulching for steeper slopes:
See Hydraulic Mulching (HM).
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Areas should
be identified where mulch has loosened or been removed. Such areas should be reseeded (if necessary) and
the mulch cover replaced. If washout, breakage, or erosion occurs, surfaces should be repaired, reseeded,
and re -mulched, and new netting should be installed. Inspections should be continued until vegetation is firmly
established.
Removal
Anchor netting and any other artificial mulch material should be removed when protection is no longer needed
and disposed of in a landfill.
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References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), Field
Office Technical Guide. 2002. <www.nrcs.usda.gov/technical/efotg>
Table M-1
Typical Mulching Materials and Application Rates
Material
Rate per
Acre
Requirements
Notes
Organic Mulches
Straw
1 - 2 tons
Dry, unchopped,
unweathered; certified
weed free.
Spread by hand or machine;
must be tacked or tied down.
Wood fiber or
wood cellulose
1/2- 1 ton
Use with hydroseeder; may
be used to tack straw. Do not
use in hot, dry weather.
Wood chips
5 - 6 tons
Air dry. Add fertilizer N,
12 Ib/ton.
Apply with blower, chip
handler, or by hand. Not for
fine turf areas.
Bark
35 yd3
Air dry, shredded, or
hammermilled, or chips
Apply with mulch blower,
chip handler, or by hand. Do
not use asphalt tack.
Nets and Mats
Jute net
Cover
area
Heavy, uniform; woven
of single jute yarn. Used
with organic mulch.
Withstands water flow.
Excelsior (wood
fiber) mat
Cover
area
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Table M-2
Mulch Anchoring Guide
Anchoring Method
or Material
Kind of Mulch
to be Anchored
How to Apply
1. Mulch netting
Hay or straw
Staple the light -weight paper, jute, wood fiber,
or plastic nettings to soil surface according to
manufacturer's recommendations. Should be
biodegradable. Most products are not suitable
for foot traffic.
2. Wood cellulose
fiber
Hay or straw
Apply hydroseeder immediately after mulching.
Use 500 lbs. Wood fiber per acre. Some
products contain an adhesive material, possibly
advantageous.
3. Mulch anchoring
tool/Crimper
Hay or straw
Apply mulch and pull a mulch anchoring tool
(blunt, straight discs) over mulch as near to the
contour as possible. Mulch material should be
"tucked" into soil surface about 3".
4. Chemical
Hay or straw
Apply Terra Tack AR 120 lbs./ac. In 480 gal. of
water (#156/ac.) or Aerospray 70 (60 gal/ac.)
according to manufacturer's instructions. Avoid
application during rain. A 24-hour curing period
and a soil temperature higher than 45 deg.
Fahrenheit are required.
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June 2008
Retaining Wall (RW)
Rock Retaining Wall
Timber Retaining Wall
Gabion Retaining Wall
Description
Retaining walls are structures that are used to stabilize and hold soil in place, gain space on roadways or well
pads, or to keep soil contained within a site boundary. This BMP will cover retaining walls constructed with
rock, boulders, or gabions. Gabions are rectangular, rock -filled wire baskets that are pervious, semi -flexible
building blocks which can be used to armor the bed and/or banks of channels or to divert flow away from
eroding channel sections.
Several different retaining wall types are:
1. Rigid gravity and semi -gravity walls. These walls may be constructed of concrete or stone
masonry. The rigid gravity and semi -gravity walls develop their capacity from their dead weights
and structural resistance, and are generally used for permanent applications.
2. Non -gravity cantilevered walls. These walls develop lateral resistance through the embedment
of vertical wall elements and support retained soil with wall facing elements. Vertical wall
elements are normally extended deep in the ground to provide lateral and vertical support. The
vertical wall elements can be piles, drilled shafts, steel sheet piles, etc. Wall faces can be
reinforced concrete, metal, or timber. Cantilevered walls are generally limited to a maximum
height of about 15 feet.
3. Anchored walls. These walls typically consist of the same elements as the non -gravity
cantilevered walls but derive additional lateral resistance from one or more tiers of anchors. The
anchored walls are typically used in the cut situation, in which the construction proceeds from the
top to the base of the wall.
Applicability
Retaining walls should be used when sites have very steep slopes or loose, highly erodible soils that cause
other methods, such as vegetative stabilization or regrading, to be ineffective. The preconstruction drainage
pattern should be maintained to the extent possible. Retaining walls may be used for the following
applications:
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June 2008
• Near the toe of a cut or fill slope to mechanically stabilize steep slopes and so that a flatter slope can
be constructed to prevent or minimize slope erosion or failure. Particularly useful along access road
cut slopes.
• Along a stream bank or drainage channel, to keep a toe of a slope from encroaching into a stream and
thus prevent potential undercutting of the toe by flowing water.
• As headwalls at culvert inlets and outlets to prevent scour and undercutting.
Limitations
• Some retaining walls are a structural element that must be professionally designed.
• To be effective, retaining walls must be designed to handle expected loads. Non -engineered
walls should not be used where traffic is expected near the top of the wall.
• Retaining walls must be properly installed and maintained to avoid failure.
• Some types of retaining walls must be placed on a good foundation, such as bedrock or firm, in-
place soil.
• Some walls have height restrictions and backfill may be required to meet specific material property
requirements.
• Materials costs and professional design requirements may make use of gabions impractical.
• When used in channels with high sediment loads, the galvanizing wire on gabion cages quickly
wears off, causing rusting and the premature failure of the cages.
Design criteria
Most retaining walls require a site-specific design. Wall heights, requirements for drainage, and suitable
materials must be determined through on-site investigation. An engineered retaining structure is a designed
structure that is supported by plans and specifications signed and sealed by a Professional Engineer. Non -
engineered retaining structures may be designed by an engineer; however, if the design is not supported by
the seal and signature, the retaining structure is not considered engineered.
Gabions
Gabions should be designed and installed in accordance with manufacturer's standards and specifications and
must be able to handle expected storm and flood conditions. At a minimum, they should be constructed of a
hexagonal triple twist mesh of heavily galvanized steel wire (galvanized wire may also receive a polyvinyl
chloride coating). The maximum linear dimension of the mesh opening shall not exceed 4 1/2 inches and the
area of the mesh opening shall not exceed 10 square inches.
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June 2008
Design velocity
The design water velocity for channels utilizing gabions should not exceed those listed as follows:
Gabion Thickness
(feet)
Maximum Velocity
(feet per second)
0.5
6
0.75
11
1.0
14
Construction specifications
Rock retaining wall guidelines
See Figure RW -1.
1. Excavate a footing trench at the location of the proposed wall.
2. Place the largest rocks in the footing trench with their longitudinal axis normal to the wall face.
Arrange subsequent rock layers so that each rock above the foundation course has a firm seating
on the underlying rocks.
3. The batter of the wall face shall be between'/2H:1V and vertical, depending upon the height of the
wall, the height of the slope, the width of the right-of-way, or other limitations on space.
4. Place fill material behind the rock wall. Slope above the wall should be maintained at 2H:1V or
flatter. Backfill the footing trench with excavated material. If a roadway is located at the toe of the
wall, pave the roadway up to the base of the rock wall and provide roadway curb for water
transport. If a roadway is not located at the toe of the retaining wall, slope the backfilled material
away from the wall.
5. Revegetate the stabilized slope with a method applicable to the particular site.
Gabion retaining wall guidelines
See Figure RW -2. Gabions shall be fabricated in such a manner that the sides, ends, and lid can be
assembled at the construction site into a rectangular basket of the specified sizes. Gabions shall be of single
unit construction and shall be installed according manufacturer's recommendations. General specifications
are listed below.
1. Clear and grade the area of trees, brush, vegetation, and unsuitable soils. Compact subgrade
firmly to prevent slumping or undercutting.
2. Install a filter fabric or granular filter according to the Riprap (R) BMP to maintain separation of
rock material with the underlying soil, if required.
3. Place empty gabion baskets. Each row, tier, or layer of baskets should be reasonably straight
and should conform to the specified line and grade (see Figure RW -2 for details). The empty
gabion baskets should be fastened to the adjacent baskets along the top and vertical edges.
Each layer should be fastened to the underlying layer along the front, back and ends. Fastening
should be performed in the same manner as provided for assembling the gabion units.
4. Unless otherwise indicated on the plans, the vertical joints between basket units of adjacent tiers
or layers, along the length of the structure, should be staggered by at least one cell.
5. Before filling each gabion with rock, all kinks and folds in the wire mesh should be removed and all
baskets should be properly aligned. A standard fence stretcher, chain fall or steel rod may be
used to stretch the wire baskets and hold alignment.
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June 2008
6. The gabion cells should be carefully filled with 4 to 8 -inch rock placed by hand/machine in such a
manner that the alignment of the structure will be maintained and so as to avoid bulges and to
minimize voids. Rock should be sound, durable, and well graded. All exposed rock surface
should have a reasonably smooth and neat appearance. No sharp rock edges should project
through the wire mesh.
7. The gabion cells in any row or layer should be filled in stages so that local deformations may be
avoided.
8. At no time should any cell be filled to a depth exceeding 12 inches more than any adjacent cell.
9. The layer of rock should completely fill the gabion basket so that the lid will bear on the rock when
it is secured. The lid should be joined to the sides, ends, and diaphragms in the same manner as
specified for joining the vertical edges. The gabion basket lid should be secured so that no more
than 1 -inch gap remains at any connection.
10. Gabion rows or layers not completed at the end of each shift should have the last gabion filled
with rock tied internally as an end gabion.
11. The area behind the gabion structure should be backfilled with granular material. Geotextile, if
required, should be spread uniformly over the back of the gabion structure. Joining edges of the
geotextile should be overlapped a minimum of 12 inches and should be anchored in position with
approved anchoring devices. The Contractor should place the backfill material in a manner that
will not tear, puncture, or shift the geotextile.
All other retaining walls should be constructed as designed by a Professional Engineer.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Check for
structural failure, erosion, damage, instability, or other signs of deterioration. In stream bank installations and
culvert inlets and outlets also inspect for signs of undercutting. Check wire of gabion cages for rusting and
wear. Repair or replace any damaged areas immediately to restore designed effectiveness and to prevent
damage or erosion of the slope or stream bank.
References
City of Knoxville, Stormwater Engineering, Knoxville BMP Manual - Best Management Practices. July 2003.
<http://www.ci.knoxville.tn.us/engineering>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
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June 2008
Figure RW -1
Construction of Rock Retaining Structures
V ruin.
t,1
Wfidih = 0.7 Haigh!
Flai Baddll Isrri aIh facet,
13
Note: L eakfat condilims are frac silly
sand to sand end gravel bacl'.iill. For
firlaS erclay nal still$,,(larthpr1> rrrq
41 11112 wall 12111 inr,.rea1A ad111 the wall
Laaem w.rllh have 10 Increase for
each hao]hl f: arA ill ye IN = 110 pef,
- Same aparnsl cn'Brturnlnp for SWIa
with a n'anilnurn hearing. capac ty of
2 Tamale
-Far SAL or 810p 11 bareklille„ either s,
nal or Slapped f8[R+Inlay tr6uaad.
NOT TO SCALE
Figure RW -2
Gabion Design
=a al
Ti 1 {fae®wilh slops)
No. 01 H I3 No. o1
levels gabions
tPer
width)
3'-' 1
2 5'-6' 4-3' 1
3 g'- 9' S'-' 2
-0 5'-f 2
5 15'1' $'-2 2;
18'-P 4F-fr 3
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RW -5
2Cr - —
B
3
a
s
5
15
HOT TO SCALE
No. nP H B No. of
levels gabions
I,Par
wider)
1 3-3r 3'-3' 1
I 5-8' 4'-11' 1 g
3 f1- 9" 5'-6' 2
4 13'-1'
5 15-0' 9'-g' 3
b 1^9'-7' 11'-5' 32
June 2008
Revegetation (RV)
Description
Revegetation involves planting seed to establish a vegetative cover on disturbed areas. Revegetation reduces
erosion and sedimentation by stabilizing disturbed areas in a manner that is economical, adaptable to site
conditions, and allows selection of the most appropriate plant materials. Revegetation also:
• Absorbs the impact of raindrops
• Reduces the velocity of runoff
• Reduces runoff volumes by increasing water percolation into the soil
• Binds soil with roots
• Protects soil from wind
• Improves wildlife habitat
• Enhances natural beauty
Applicability
Revegetation is most effective on slopes no steeper than 2:1 and may be used in areas where exposed soil
surfaces are not to be regraded for periods longer than 30 days. Such areas include denuded areas, soil
stockpiles, berms, temporary road banks, etc.
Limitations
The effectiveness of revegetation can be limited due to the following:
• High erosion potential during establishment.
• The need for stable soil temperature and soil moisture content during germination and early growth.
• The need to reseed areas that fail to establish.
Proper seedbed preparation and the use of quality seed are important in this practice. Failure to carefully
follow sound agronomic recommendations will often result in an inadequate stand of vegetation that provides
little or no erosion control.
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Seeding does not immediately stabilize soils. Prior to seeding, install necessary erosion and sediment control
practices such as diversions, straw bales, and basins until vegetation is established.
Design criteria
Successful plant establishment can be maximized with proper planning; consideration of soil characteristics;
selection of plant materials that are suitable for the site; adequate seedbed preparation, liming, and
fertilization; timely planting; and regular maintenance. A Revegetation Manual, which indicates the methods
and materials needed to accomplish revegetation on differing site conditions, is provided as Appendix B to the
Stormwater Management Plan (SWMP).
Coordination and scheduling
1. Coordinate installation of seeding materials during normal planting seasons for each type of seed
material required.
2. Seeding in areas that are non -irrigated or not provided with sprinkling or watering systems shall be
restricted according to the following schedule:
a. Below 6000' elevation: Spring seeding shall occur between spring thaw and July 1st. Fall seeding
shall occur from September 1st until consistent ground freeze.
b. 6000' to 7000' elevation: Spring seeding shall occur between spring thaw and July 1st. Fall
seeding shall occur from August 15th until consistent ground freeze.
c. 7000' to 8000' elevation: Spring seeding shall occur between spring thaw and July 15th. Fall
seeding shall occur from August 1st until consistent ground freeze.
d. Above 8000' elevation: Seeding shall occur from spring thaw until consistent ground freeze.
e. Spring thaw shall be defined as the earliest date in a calendar year in which seed can be buried 1/2
inch into the topsoil thru normal drill seeding methods.
f. Consistent ground freeze shall be defined as that time during fall months in which the topsoil, due
to freeze conditions, prevents burying seed 1/2 inch thru normal drill seeding operations.
Seed, soil amendments, and fertilizer
1. Seed mixes will vary depending on landowner requirements and the site elevation.
2. Soil amendments:
a. AV Superphosphate 18-46-0: Commercial, phosphate mixture, soluble; minimum of 20
percent available phosphoric acid.
Arkansas Valley Seed, 400 Moffat CR 220, Craig, CO 81625
Willard McLaughlin - District Sales Manager
Mobile: 970-629-0263. Fax: 970-234-8023
Email: wmmclaughlin@seedsolutions.com
b. Other soil amendments may also be used.
3. Fertilizers:
a. Sustane 8-2-4: Slow release granular fertilizer.
Sustane — Natural Fertilizer of America, Inc.
310 Holiday Avenue P.O. Box 19 Cannon Falls, MN 55009
Phone: 1-800-352-9245 Fax: 507-263-3029 www.sustane.com
b. Other fertilizers may also be used.
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Mulches
See Mulching (M) and Hydraulic Mulching (HM) for mulch materials to be used for flat and steep slopes,
respectively.
Erosion control materials
1. Flexible Growth Medium: Flexterra FGM. Strictly comply with manufacturer's installation instructions
and recommendations. Use approved hydro -spraying machines with fan -type nozzle (50 -degree tip).
Apply FGM from opposing directions to soil surface.
Nilex, 15171 E. Fremont Drive, Centennial, CO 80112
Phone: 1-800-537-4241 Fax: 303-766-1110 www.nilex.com
2. Non -asphaltic Tackifier: Organic derivative vegetative gum tackifier recommended by fiber -mulch
manufacturer for slurry application, nontoxic and free of plant growth- or germination -inhibitors.
3. Other erosion control materials may also be used.
Construction specifications
See Table RV -1 for typical seeding guidelines. See Table RV -2 for typical seeding guidelines when using an
Erosion Control Blanket (ECB) or a Turf Reinforcement Mat (TRM).
Seeding
1. Do not use wet seed or seed that is moldy or otherwise damaged in transit or storage.
2. Seed shall be uniformly sown by drill, by hydro -seeding (without mulch admixture), or by broadcasting.
Drill and Hydro -seeding rates shall be the amount specified. Broadcast seeding rates shall be one
and a half times the amount specified. Broadcast seeding shall be raked or chain dragged into the soil
to a depth of approximately one-quarter inch (1/4") to one-half inch (1/2").
3. The seeding shall be done in one application crossing the area at right angles to one another to
guarantee even coverage.
4. Protect seeded areas against erosion by uniformly spreading mulch after completion of seeding
operations in accordance with Mulching (M) and Hydraulic Mulching (HM).
Cleanup and protection
1. During stormwater management & reclamation activities, keep pavements clean and work areas in an
orderly condition.
2. Protect well pad, access road, private property, and federal lands from damage due to stormwater
management & reclamation operations, operations by other contractors and trades, and trespassers.
Maintain protection during installation and maintenance periods. Treat, repair, or replace damaged
well pad, access road, private property, and federal lands work as directed.
Maintenance considerations
The frequency of inspections should be in accordance with the SWMP. Vegetation is considered established
when a density of at least 70 percent of pre -disturbance levels has been reached. Seeded areas should be
inspected for failure and any necessary repairs and re-seedings should be made within the same season, if
possible.
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References
EnCana Oil & Gas (USA), Inc, Revegetation Manual. Chenoweth & Associates Environmental Consultants.
2007.
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
High Mesa Water Park Seeding Specifications. April 2006.
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
United States Army Corps of Engineers (USACE), Engineering and Design - Handbook for the Preparation of
Storm Water Pollution Prevention Plans for Construction Activities. February 1997.
http://www.usace.army.mil/inet/usace-docs/eng-pamphlets/ep1110-1-16/
Table RV -1
Typical Seeding Guidelines
All slopes accessible to drill seeder and straw crimper
Material
Description
Quantity
Seed Mix
Drill Seeding (twice in perpendicular directions)
20 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1000 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
Certified Weed Free Straw
Weed Free Crimped Straw
2000 lbs./acre
All slopes accessible to drill seeder
Material
Description
Quantity
Seed Mix
Drill Seeding (installed in perpendicular directions)
20 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1000 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
Four wheeler broadcast seeding & tine harrowin
Material
Description
Quantity
Seed Mix
Broadcast Seeded & Tine Harrowed
40 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1000 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
Chest broadcast seeding & hand rakin
Material
Description
Quantity
Seed Mix
Broadcast Seeded & Hand Raked
40 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1000 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
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Table RV -2
Typical Seeding Guidelines if using
Erosion Control Blankets (ECB) or Turf Reinforcement Mats (TRM)
SLOPES 1:1 and/or Greater and Medium to High Concentrated Flows
Material
Description
Quantity
Seed Mix
Seed Hydraulically Applied
50 lbs./acre
Guar Tackifier
Guar Tackifier (Nylex dlamanna@nilex.com)
75 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1100 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
ECB or TRM
Per Table ECB -1 or TRM-1
per spec.
SLOPES 2:1 to 1:1 and Medium Concentrated Flows
Material
Description
Quantity
Seed Mix
Seed Hydraulically Applied
45 lbs./acre
Guar Tackifier
Guar Tackifier (Nylex dlamanna@nilex.com)
75 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1100 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
11001bs./acre
ECB or TRM
Per Table ECB -1 or TRM-1
per spec.
SLOPES 2:1 to 3:1 and Medium Concentrated Flows
Material
Description
Quantity
Seed Mix
Broadcast Seeding
45 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1100 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
ECB or TRM
Per Table ECB -1 or TRM-1
per spec.
SLOPES 3:1 or less and Low Concentrated Flows
Material
Description
Quantity
Seed Mix
Seed Hydraulically Applied
40 lbs./acre
Guar Tackifier
Guar Tackifier (Nylex dlamanna@nilex.com)
40 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1100 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
ECB or TRM
Per Table ECB -1 or TRM-1
per spec.
SLOPES 3:1 or Tess and Low Concentrated Flows
Material
Description
Quantity
Seed Mix
Broadcast Seeding
40 lbs./acre
SUSTANE 8-2-4
Sustane 8-2-4 (Nylex dlamanna@nilex.com)
1100 lbs./acre
Soluble Humates
Soluble Humates (Nylex dlamanna@nilex.com)
1100 lbs./acre
ECB or TRM
Per Table ECB -1 or TRM-1
per spec.
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June 2008
Riprap (R)
Description
Riprap is a permanent, erosion -resistant layer made of stones or boulders. It is intended to stabilize areas
subject to erosion and protect against scour of the soil caused by concentrated, high velocity flows.
Applicability
Riprap can be used for areas subject to erosion or weathering, particularly where conditions prohibit the
establishment of revegetation or where flow velocities exceed 5 ft/sec. Riprap may be used in the following
applications:
• Cut -and -fill slopes
• Channel side slopes and/or bottoms
• Inlets and outlets to sediment traps
• Roadside ditches
Limitations
Riprap is limited by steepness of slope, because slopes greater than 1.5:1 have potential riprap loss due to
erosion and sliding. When working within flowing streams, measures should be taken to prevent excessive
turbidity and erosion during construction. Bypassing base flows or temporarily blocking base flows are two
possible methods.
Design criteria
Gradation
A well -graded mixture of rock sizes should be used instead of one uniform size (with the exception of dry
stacking boulders). 50% by weight should be larger than the specified design size. The diameter of the
largest stone size in such a mixture should be 1.5 times the d50 size with smaller sizes graded down to 1 inch.
When dry stacking up a slope, boulders may be uniform in size or may get gradually smaller as the boulders
are placed up the slope.
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June 2008
Quality
Riprap must be durable so that freeze/thaw cycles do not decompose it in a short time. They should be
angular and not subject to breaking down when exposed to water or weathering. The specific gravity should
be at least 2.5.
Size
The sizes of stones used for riprap protection are determined by purpose and specific site conditions:
1. Slope Stabilization. Riprap stone for slope stabilization not subject to flowing water should be sized
for the proposed grade. The gradient of the slope to be stabilized should be less than the natural
angle of repose of the stone selected. Angles of repose of riprap stones may be estimated from
Figure R-1. Riprap used for surface stabilization of slopes does not add significant resistance to
sliding or slope failure and should not be considered a retaining wall. Slopes approaching 1.5:1 may
require special stability analysis. The inherent stability of the soil must be satisfactory before riprap is
used for surface stabilization.
2. Stream bank Protection. If the shear stress is estimated, riprap stone for stream bank protection can
be selected from the gradations in Table R-1, below. The shear stress can be estimated from the
depth of flow and the channel slope (see note for Table R-1). The riprap should extend 2 feet below
the channel bottom and be keyed into the bank both at the upstream end and downstream end of the
proposed work or reach.
Filter material
Filter material is sometimes used between riprap and the underlying soil surface to prevent soil from moving
through the riprap. Filter cloth material or a layer of sand and/or gravel is usually used for the filter.
The design of a sand/gravel filter blanket is based on the ratio of particle size in the overlying filer material to
that of the base material in accordance with the criteria below. Multiple layers (each a minimum of 6 inches
thick) may be designed to affect a proper filter if necessary. A sand/gravel filter blanket should have the
following relationship for a stable design:
d15 filter
d85 base <_ 5
d15 filter
5 < d50 base <_ 40
d50 filter
d50 base <_ 40
The design of a synthetic filter fabric, which may be used with or in place of gravel filters, is based upon the
following particle size relationships:
1. Filter fabric covering a base containing 50% or less by weight of fine particles (#200 sieve size):
a. d85 base (mm)
EOS*filter fabric (mm) > 1
b. total open area of filter fabric should not exceed 36 %
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June 2008
2. Filter fabric covering other soils:
a. EOS is no larger than 0.21 mm (#70 sieve size)
b. total open area of filter fabric should not exceed 10%
*EOS - Equivalent opening size compared to a U.S. standard sieve size
No filter fabric should have less than 4% open area or an EOS less than U.S. Standard Sieve #100 (0.15 mm).
The permeability of the fabric must be greater than that of the soil. The fabric may be made of woven or non-
woven monofilament yarns and should meet the following minimum requirements:
Thickness 20-60 mils
Grab strength 90-120 lbs
Conform to ASTM D-1682 or ASTM D-177
Construction specifications
See Figure R-2 for riprap slope stabilization and stream bank protection. See Figure R-3 for dry stacking
boulders. See Sediment Trap (ST) for a detail of a riprap lined channel leading into a sediment trap.
1. Subgrade Preparation. Prepare the subgrade for riprap to the required lines and grades shown on the
plans. Compact any fill required in the subgrade to a density approximating that of the undisturbed
material or overfill depressions with riprap. Remove brush, trees, stumps, and other objectionable
material. Cut the subgrade sufficiently deep so that the finished grade of the riprap will be at the
elevation of the surrounding area. Channels should be excavated sufficiently to allow placement of
the riprap in a manner such that the finished inside dimensions and grade of the riprap meet design
specifications.
2. Sand/gravel filter blanket. If using a granular filter, spread filter stone in a uniform layer to the
specified depth. Where more than one layer of filter material is used, spread the layers with minimal
mixing.
3. Synthetic filter fabric. If using a filter fabric, place the cloth directly on the prepared foundation. Where
large stones are to be placed, a 4 -1 -inch layer of fine sand or gravel is recommended to protect the
filter cloth. Filter fabric is not recommended as a filter on slopes steeper than 2 horizontal to 1 vertical.
4. Stone placement. Place riprap so that it forms dense, well -graded mass of stone with a minimum of
voids. The desired distribution of stones throughout the mass may be obtained by selective loading at
the quarry and controlled dumping during final placement. Place riprap to its full thickness in one
operation. Do not place riprap by dumping through chutes or other methods that cause segregation of
stone sizes. If a filter is used, be careful not to dislodge the underlying base filter or damage the filter
cloth when placing the stones. If damage occurs, remove the riprap and repair filter.
5. The toe of the riprap should be keyed into a stable foundation at its base as shown in Figure R-2 if
required for slope stabilization and stream bank protection. The finished slope should be free of
pockets of small stone or clusters of large stones. Hand placing may be necessary to achieve proper
distribution of stone sizes to produce a relatively smooth, uniform surface. The finished grade of the
riprap should blend with the surrounding area.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan (SWMP). If
riprap has been damaged or dislodged, repairs should be made to prevent a progressive failure. If repairs are
needed repeatedly at one location, the site should be evaluated to determine if the original design conditions
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1:1
Slope (H:V)
— 1.5 : 1
have changed. Channel obstructions such as trees and sediment bars can change flow patterns and cause
erosive forces that may damage riprap. Control of weed and brush growth may be needed in some locations.
Removal
Riprap is generally not removed.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
Table R-1
Riprap Gradations
Unit shear stress (Ib/ft2)
D50
dmax
Minimum blanket
thickness (inches)
0.67
2
4
6
2
6
9
14
3
9
14
20
4
12
18
27
5
15
22
32
6
18
27
32
7.8
21
32
38
8
24
36
43
Unit shear stress calculated as T=y*d*s where:
T = shear stress in Ib/ft2
y = unit weight of water, 62.4 Ib/ft2
d = flow depth in ft
s = channel gradient in ft/ft
45
40'
Angle of
Repose
35a
30
Figure R-1
Angles of Repose of Riprap Stones
Clashed Rik
Angular Rock;
Rounded Stones
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4" 1-1 10- Z0„ 40"
R-4
June 2008
Figure R-2
Typical Riprap Slope Protection Detail
5 (min.)
NOT TO SCALE
MOTTO SCALE
{irao41I hllni
urilIi iul iI
Figure R-3
Typical Boulder Drystack Detail
She Re Beuklera
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R-5
Z T110.
June 2008
Soil Stabilizers (SS)
Description
Soil stabilizers (also known as soil binders) consist of stabilizing emulsions that are applied directly to the
surface of disturbed soil to temporarily reduce soil erosion. Soil binders are categorized as:
• Short-lived plant -based materials
• Long-lived plant -based materials
• Polymeric emulsion blends (acrylic polymers)
• Cementitious-based binders
Applicability
Soil binders are used on bare soil areas where vegetation may not be desired (such as near compressor
stations) in order to reduce soil loss. Soil binders are also suitable for use on stockpiles.
Limitations
• Soil binders are a temporary measure.
• Product must be reapplied 6-12 months after initial application.
• Soil binders may not be compatible with certain soils.
• Runoff can penetrate a treated area at the top of a slope, undercut the treated soil, and cause
spot failures by discharging at a point further down the slope.
• Performance depends on temperature, humidity, and traffic across treated areas.
Design criteria
No formal design is required.
Construction specifications
1. Soil binder must be non-toxic to plant and animal life. Some examples include Guar, Starch, Pitch
& Rosin Emulsion, Liquid Polymers of Methacrylates & Acrylates, and Gypsum. However, many
others are available and may be used. Select a soil binder that is appropriate for the region, use
and soil type.
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June 2008
2. Soil binder is typically mixed in a water truck or hydroseeder and applied in a liquid state. Use
emulsion formulas for applications with water trucks.
3. Apply soil binder over a roughened soil surface on slopes not greater than 1 H:1 V. Do not apply
immediately before or during a rain event or where standing water is present.
4. Soil binder can be applied in combination with organic fertilizers and humates, if desired.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan (SWMP).
Inspect for rill erosion and reapply soil binder if necessary, usually every 6 to 12 months or when the surface
has been disturbed.
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
http://www.dot.state.co.us/environmental/envWaterQual/wqms4.asp
California Stormwater Quality Association, Stormwater Best Management Practice (BMP) Handbook —
Construction. January, 2003. <http://www.cabmphandbooks.com/Construction.asp>
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June 2008
Stockpiling (SP) — Topsoil and Subsoil
Description
Stockpiling during construction of well pads involves the removal and stockpiling of all surface soil materials
(topsoil) from the entire cut and fill area for later reuse during interim and final reclamation. Topsoil provides a
planting and growth medium that is more desirable than deeper subsoils for use during reclamation and
revegetation activities. If there is an excess of cut material, however, subsoil may als7o be stockpiled.
Stockpiling during construction of roads involves the removal and temporary stockpiling of all surface soil
materials (topsoil) from the entire cut and fill area for reuse along cut and fill slopes and roadside ditches. This
helps to reduce the loss of forage, habitat, and sediment, decreases maintenance costs, and helps maintain
the scenic quality. If there is an excess of cut material, subsoil may also be stockpiled.
Applicability
Stockpiling applies for the construction of all well pads, roads, pipelines, and any other construction activity
where soil is disturbed and later revegetated.
Limitations
• Stockpiling increases the overall area of disturbance at a site.
• Stockpiles often require revegetation and also require other erosion and sediment controls
during the establishment of vegetation such as silt fences or diversions.
Design criteria
No formal design is required.
Construction specifications
Location
1. Locate the stockpile so that it meets specifications and does not interfere with work on the site.
2. Stockpiles should be located and protected so that wind and water erosion are minimized and
reclamation potential is maximized.
3. Stockpiles located down slope of a well pad will serve as tertiary spill containment and a reservoir
during storm events. See Figure SP -1.
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June 2008
4. Stockpiles located upslope of a well pad will serve as a berm to divert surface runoff around the
site and to a stabilized outlet. See Figure SP -2.
5. During the installation of pipelines, soil will be stockpiled according to Figure SP -3.
Stripping and excavation
1. All perimeter stormwater controls shall be in place prior to stripping topsoil or excavating subsoil.
2. Stripping shall be confined to the immediate construction areas.
3. The depth of topsoil to be stripped and stockpiled should be determined during an on-site
inspection prior to the start of any excavation activity, but is commonly 4 to 6 -inches.
Stockpiling
1. Soil shall be stockpiled in such a manner that natural drainage is not obstructed and no off-site
sediment damage shall result.
2. Keep topsoil segregated and stored separately from subsoil materials to avoid mixing during
construction, storage, and interim reclamation. Never place subsoil materials on top of topsoil
material.
3. Side slopes of the stockpile shall not exceed 2:1.
4. Stockpiles should be tracked according to Surface Roughening (SR) and stabilized to prevent
erosion and off-site sedimentation. Perimeter controls shall be placed around the stockpile
immediately. This may involve a diversion to route sediment laden runoff to a stabilized outlet, a
silt fence to capture sediments, or any other applicable stormwater perimeter control.
Revegetation of the stockpile, according to Revegetation (RV), can help reduce erosion as well as
maintain its biological viability.
Topsoiling during reclamation
Part of the reclamation process involves salvaging and reusing all available topsoil to spread over disturbed
areas prior to revegetation. Reclamation measures should begin as soon as possible after the disturbance
and continue until successful reclamation is achieved.
1. Well pads — interim reclamation — Minimize the footprint of disturbance by reclaiming all
portions of the well site not needed for production operations. Respread topsoil over areas not
needed for operations prior to revegetation.
2. Well pads — final reclamation — Where the topography is flat and it is, therefore, unnecessary to
recontour the well location at the time of final reclamation, the operator should set aside sufficient
topsoil for final reclamation of the small, unreclaimed area around the wellhead. On sloped
ground, during final reclamation, the topsoil and interim vegetation must be restripped from
portions of the site that are not at the original contour, the well pad recontoured, and the topsoil
respread over the entire disturbed site to ensure successful revegetation.
3. Roads — interim reclamation — Reclaim portions of the road not needed for vehicle travel
wherever possible by covering cut slopes, fill slopes, and borrow ditches with topsoil salvaged
during road construction prior to revegetation.
4. Pipelines — final reclamation — Reclaim disturbed area on completion of pipeline installation.
The stripped topsoil shall be respread over the entire ROW to ensure successful revegetation.
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June 2008
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan (SWMP).
Inspect for rills and other evidence of stockpile erosion. Also inspect perimeter stormwater controls in
accordance with the appropriate BMP.
Removal
Stockpiles may be removed when the site is ready for interim or final reclamation.
References
United States Army Corps of Engineers (USACE), Engineering and Design - Handbook for the Preparation of
Storm Water Pollution Prevention Plans for Construction Activities. February 1997.
<http://www.usace.army.mil/inet/usace-docs/eng-pamphlets/ep1110-1-16/>
United States Department of the Interior and United States Department of Agriculture. Surface Operating
Standards and Guidelines for Oil and Gas Exploration and Development "Gold Book." BLM/WO/ST-
06/021+3071. Bureau of Land Management (BLM). Denver, Colorado. Fourth Edition, 2006.
Figure SP -1
Topsoil Stockpile — Located Below Well Pad
Berri
Pa
f €rrac "q
NOT TO SCALE
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SP -3
T;'Pa 1I Pile Tracking
V'egelater1 Butter
Diversion
June 2008
Veyelated &uffnr
NOT TO SCALE
Figure SP -2
Topsoil Stockpile — Located above Well Pad
Tui File
-r9::kng
R 0.W
Boundary
Figure SP -3
Topsoil Stockpile for Pipeline Installation
I Lip orl storage
(Store topsoil cn taap3l)
Trench Spol -
ri -
NOT TO SCALE
Spgi Sltlr
rj
Additional
loprroII storage
R.0 W
Boundary
Thr
Piper*
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Warti tag Skis
SP -4
June 2008
Surface Roughening (SR)
Corrugating
Minibenching
Tracking
Description
Surface (soil) roughening is a temporary erosion control practice often used in conjunction with grading. Soil
roughening involves increasing the relief of a bare soil surface using construction equipment. Slopes that are
not fine graded and that are left in a roughened condition can reduce erosion. Soil roughening reduces runoff
velocity, increases infiltration, reduces erosion, traps sediment, and prepares the soil for seeding and planting
by giving seed an opportunity to take hold and grow. The following types of soil roughening are discussed in
this BMP:
• Corrugating
• Tracking
• Minibenching
Applicability
Soil roughening is most effective for areas of 1 acre or less, and works well for the following applications:
• Any slope, but particularly fill slopes greater than 3:1
• Areas with highly erodible soils
• Soils that are frequently disturbed
• Prior to application of permanent or temporary seeding
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SR -1
June 2008
Limitations
• Soil roughening is not appropriate for rocky slopes.
• Soil compaction might occur when roughening with tracked machinery.
• Soil roughening is of limited effectiveness in anything more than a gentle or shallow depth rain.
• If roughening is washed away in a heavy storm, the surface will have to be re -roughened and new
seed laid.
Design criteria
No formal design required. However, the selection of the appropriate method (corrugating or tracking)
depends on the type of slope. Steepness, mowing requirements, and/or a cut or fill slope operation are all
factors considered in choosing a roughening method.
Construction specifications
To slow erosion, roughening should be done as soon as possible after grading activities have ceased
(temporarily or permanently) in an area. All cut and fill slopes should be roughened wherever possible. Do not
blade or scrape the final fill slope face. Excessive compacting of the soil surface should be avoided during
roughening, and areas should be seeded as quickly as possible after roughening is complete.
Corrugating
Corrugating (Figure SR -1) uses machinery to create a series of ridges and depressions that run across the
slope on the contour. Groove using any appropriate implement that can be safely operated on the slope, such
as disks, tillers, spring harrows, or the teeth of a front-end loader bucket. Do not make the grooves less than
3 inches deep or more than 15 inches apart.
Tracking
Tracking is the most common method of soil roughening and is sometimes used as a method to hold down
mulch. However, tracking is generally not as effective as corrugating. Tracking should be used primarily in
sandy soils to avoid undue compaction of the soil surface. Operate tracked machinery up and down the slope
to leave horizontal depressions in the soil (Figure SR -2). Do not back -blade during the final grading operation.
Minibenching
Benches shall be constructed on an even contour line. Benches shall be constructed approximately 2 feet
deep and according to Figure SR -3.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Roughening
might need to be repeated after storm events. Inspections of roughened slopes will indicate where additional
erosion and sediment control measures are needed. If rills appear, they should be filled, graded again, and
reseeded as soon as possible. Proper dust control methods should be used.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
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SR -2
June 2008
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
CUT FURROWS ALONG THE CONTOUR.
IRREGULARITIES IN THE Salt suiRFACE
CATCH 'RAINWATER AtN) RETAIN LMAC,
FERTILIZER ADD SEED
NOT 10 SCALE
3' 11:
Figure SR -1
Corrugating
15- rr.g.,
Figure SR -2
Tracking
RL h4 444 d. Li 3*
3
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>-4
! 3 3. ! ! 3 t 3 3 3 3
SR -3
June 2008
Figure SR -3
Minibenching
GUT BENCHES ALONG
THE CONTOUR.
NOT TO SCALE
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SR -4
June 2008
Terracing (T)
Description
Terraces (also called benches or contour trenches) are properly spaced along a cut or fill slope and made of
either earthen embankments, ridge and channel systems, or are cut directly into a rock face of a cut slope.
Terraces are often constructed with an adequate grade to promote drainage to a stabilized outlet. Terraces
reduce damage from erosion by collecting and redistributing surface runoff to stable outlets at slower speeds
and by decreasing the distance of overland runoff flow. They also surpass smooth slopes in holding moisture
and help to minimize sediment loading of surface runoff. When terraces are constructed into steep bedrock
faces they help to stabilize the slope by catching loose rocks and other material which may fall from above.
Applicability
Terraces are most effective for areas less than 10 acres in size and, are suitable for the following applications:
• Areas with an existing or expected water erosion problem and no vegetation.
• Cut or fill slopes greater than 5 feet in height, which are not part of a trench or excavation.
• Graded areas with smooth hard surfaces or any cleared area prior to seeding.
• Where the length of slopes need to be shortened by terracing.
• On steep rock walls, particularly those greater than 60 feet in height.
Limitations
• Terraces are not appropriate for use on sandy or shallow soils.
• If too much water permeates the soil in a terrace system, sloughing could occur, and cut and fill
costs could increase substantially.
Design criteria
The design of terraces should be determined by a civil engineer based upon actual site conditions.
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T-1
June 2008
Construction specifications
In the absence of a specific design, terraces may be constructed according to Figure T-1 for cut slopes and
Figure T-2 for fill slopes.
1. Construct diversion ditches at the top of the slope (if necessary for large upslope drainage areas)
to prevent or reduce surface water from running down the slope face.
2. The upper terrace should begin immediately below the top of the fill slope. Continue constructing
terraces down to the toe of the slope. Terraces shall be a minimum of 6 feet wide. However, a
minimum width of 8 feet is ideal so that a crimper has access for mulching.
3. Terraces must drain to a stabilized outlet, such as a stabilized waterway, vegetated area, or other
suitable outlet. Slope drains (Slope Drain (SD)) may be needed to convey surface runoff from the
terraces or benches to the toe of the slope without causing erosion. Analysis of the local site
conditions should determine the needed outlets.
4. Remove the loose material that collects at the end of terraces or benches and blend the ends of
each terrace or bench into the natural ground surface.
5. Stabilize or revegetate the slope with methods applicable to the particular site.
For terraces constructed into high rock walls of cut slopes, the vertical spacing may be anywhere from 10
to 100 feet and the width anywhere from 6 to 100 feet, as determined by a civil engineer.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Maintain
terrace ridge height and outlet elevations. Remove sediment that has accumulated in the terrace to maintain
capacity and a positive channel grade. If excessive seepage or surface runoff is a problem, control the
seepage/runoff with appropriate drainage facilities. Take prompt action as needed to ensure proper drainage
and slope stability. Repair rills and reseed damaged areas as they develop. Substantial maintenance of the
newly planted or seeded vegetation may be required.
References
City of Knoxville, Stormwater Engineering, Knoxville BMP Manual - Best Management Practices. July 2003.
http://www.ci.knoxville.tn.us/engineering
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), Field
Office Technical Guide. 2002. <www.nrcs.usda.gov/technical/efotg>
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T-2
June 2008
Diversion
Figure T-1
Terracing — Cut Slopes
elerrrial sicee line
2:1 1 11:V) Err Utter
Ditch to catch
loose material
Diverakwn
Slum MaXIFiluM
SirVirKeighl
2:1 2t7
31
30
4V
NOT1Q$CAJ.E
Pad
aerie
Maximum
sliarxr Nnight
bee title
1 Terraces shall slope between 2% am] rwtcl slab-He:Rd 04Jile1
2. RD..... length slung 18114:148 4/i211 not ex.r.A.84.1 BOO foo.
Figure T-2
Terracing — Fill Slopes
Normal %lope. km
2:1 [H:fla1
SlOpe Ivlakurnyn
Slope 1-l9,I
2'1 ZO'
3:1
4:1 40'
NOT TO $GALE
5:1 Of lanai
MEMITILIM UteflIoi
slupe. 1-4e3ighC Wow malarial
See kale
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Verayleled Buffer
Divi
1. Terraces shall slope henoveen 2% an4 3% to a stabezed
2. Flow length along a larracethII NA exceed WO feet.
T-3
June 2008
Turf Reinforcement Mat (TRM)
Description
A turf reinforcement mat (TRM) is a rolled permanent erosion control product composed of UV -stabilized, non-
degradable, synthetic materials (which may include an organic, biodegradable fiber component) processed
into a three-dimensional matrix. TRMs are typically installed in ditches, swales, channels, and slopes where
design discharges exert velocities and shear stresses that exceed the limits of mature, natural vegetation to
prevent erosion.
Applicability
TRMs may be used in the following applications:
• To control erosion on steep slopes and to promote the establishment of vegetation.
• To stabilize channels against erosion from concentrated flows.
• Used in transition areas before and after hard armor (i.e., riprap, concrete, asphalt etc.) to provide
for stable and non-erosive transition.
• May be used on slopes steeper than 1:1.
Limitations
• In an unvegetated state, velocities should not exceed 14 ft/sec maximum or the limitations
provided by the manufacturer.
• In a vegetated state, velocities should not exceed 25 ft/sec maximum or the limitations provided
by the manufacturer.
• Maximum slope is dictated by the soil stability and above referenced limited velocity and shear
stress limitations.
• Soils must be conducive to the establishment of vegetation.
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TRM-1
June 2008
Design criteria
No formal design is required.
Construction specifications
1. All vegetation, roots, rocks, and other objectionable material shall be removed and disposed of so
as not to create loss of soil contact by the TRM when installed.
2. Select the appropriate TRM. North American Green Products are listed in Table TRM-1.
However, other products, such as Green Armor (www.greenarmorsystem.com) may also be used.
Site specifics shall dictate TRM use.
3. Select the appropriate seed mix according to Revegetation (RV). Apply seed prior to fabric
installation for stabilization of construction sites.
4. Installation of the blankets shall be in accordance with the manufacturer's recommendations and
according to Figure TRM-1. For blankets being placed in channels, the fabric should be rolled out
parallel to the channel if the width is sufficient to cover the entire width of the channel. The fabric
needs to be in continuous contact with exposed soil.
5. Pins or staples shall be made of wire 0.162 -inch or larger in diameter. "U" shaped staples shall
have legs 8" long, and a 1" crown. "T" shaped pins shall have a minimum length of 8". The bar of
the "T" shall be at least 4" long. Triangular survey stakes can also be used.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspections
should determine if cracks, tears, or breaches have formed in the fabric. If the effectiveness of the BMP has
been reduced, the fabric should be repaired or replaced immediately. Re -anchor loosened matting and
replace missing matting and staples as required. It is necessary to maintain contact between the ground and
the blanket at all times. Trapped sediment should be removed after each storm event.
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
North American Green, 2004. http://www.nagreen.com
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TRM-2
June 2008
Table TRM-1
Suggested Blanket Types
Description (North American Green Product #)
Longevity
Applications
Max. Flow
Velocity
(feet/sec.)
Three UV Stable Nets
Top Net 5 Ib. Black
Corrugated Center Net 24 Ib. Black
Bottom Net 5 Ib. Black
70% Straw / 30% Coconut Matrix Material (SC250)
24 month grow-
in period
1:1 & Greater
Slopes
Medium to
High Flow
Channels
9.5 (unveg.)
15 (veg.)
Three UV Stable Nets
Top Net 8 Ib. Black
Corrugated Center Net 24 Ib. Black
Bottom Net 8 Ib. Black
100% Coconut Fiber Matrix Material (C350)
36 month grow-
in period
1:1 & Greater
Slopes
High Flow
Channels
10.5 (unveg.)
20 (veg.)
Three UV Stable Nets
Top Net 24 Ib. Black
Corrugated Center Net 24 Ib. Black
Bottom Net 24 Ib. Black
100% Polypropylene Fiber Matrix Material (P550)
36 month grow-
in period or
when sparse
vegetation
stand is
expected
1:1 & Greater
Slopes
Extreme High
Flow
Channels
12.5 (unveg.)
25 (veg.)
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TRM-3
June 2008
Roo
Figure TRM-1
Turf Reinforcement Mat Installation
Duire qimIciw.- rg•ti blar144:1. iii
If01V11 i 10C17., by d"
Here
eta Mot
sectored en trench
Me 8 6° owerlap where One nal
erblanke.1 ends and waffler bowls
ra! a 4trwtaverety wherever tvg3
2 weans of Waitel are applied soda
by side.
Sitaplie p31.18dt rolinirmirl 3 par
square y..1rd.
Flaw
&onkel fabric
anchored in trench
dnt't &Mold be Made every 11V. Insert a Mid rif Itin Wankel
t: 4 ; Ante a lx,enchlr witiy 6' deep and tarnp firrnly Lny tho biariNoi
smoothly Cf the surface ar the sell. 00 not strata) Lhe blankaL
do f allow wrinkles. Install Staple 20' 811 center in trench.
1 M.
IF Nssoe ()lactase blantel with a %Alt that is
wrEln enrJugh to reach all !he way OEM= the
channel, Plage' hLni1 nelled * the drecixerl
flow Do Not jowl stem In the ceetef or *WI
Ul thatk Slab. as reqt...ed
ENankeL fabric
anchored in trench
1318nkul fii
anchored in trench
PIRM blanket parallel to !he
*rectal cri kw and anarrcr
securely. thing blanket La a
laieol mrI 1141WrirninatIFISI
lhl installalmx
Nor TO SCALE
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TRM-4
June 2008
Vegetated Buffer (VB)
Description
Vegetated buffers (also known as vegetated filter strips) are areas of either natural or established vegetation
that are maintained to protect the water quality of neighboring areas. Buffers reduce the velocity of stormwater
runoff, provide an area for the runoff to permeate the soil, contribute to groundwater recharge, and act as filters
to catch sediment. The reduction in velocity also helps to prevent soil erosion.
The use of existing natural vegetation is preferred over newly established vegetation for the following reasons:
• Can process higher quantities of stormwater runoff than newly seeded areas.
• Does not require time to establish.
• Has a higher filtering capacity than newly planted vegetation because aboveground and root
structures are typically denser.
• Reduces stormwater runoff by intercepting rainfall, promoting infiltration, and lowering the water table
through transpiration.
• Provides a fully developed habitat for wildlife.
Applicability
Vegetated buffers can be used in any area that is able to support vegetation but they are most effective and
beneficial on floodplains, near wetlands, along streambanks, and as stabilized outlets to runoff controls such
as diversions, water bars, or culverts. Buffers are also effective in separating land use areas that are not
compatible and in protecting wetlands or water bodies by displacing activities that might be potential sources
of non -point source pollution.
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VB -1
June 2008
Limitations
• Vegetated buffers require plant growth before they can be effective, and land on which to plant the
vegetation must be available.
• Although vegetated buffers help to protect water quality, they usually do not effectively counteract
concentrated stormwater flows to neighboring or downstream wetlands.
Design criteria
No formal design is required.
Construction specifications
1. Buffer widths should be determined after careful consideration of slope, vegetation, soils, depth to
impermeable layers, runoff sediment characteristics, type and quantity of stormwater pollutants,
and annual rainfall. Buffer widths should increase as slope increases.
2. Zones of vegetation (native vegetation in particular), including grasses, deciduous and evergreen
shrubs, and understory and overstory trees, should be intermixed.
3. Fertilizing seeded or planted ground may enhance growth (and improve its effectiveness as a
buffer).
4. When using naturally vegetated areas, vegetation should be marked for preservation before
clearing activities begin. Barriers may be used to prevent the approach of equipment within
protected areas.
5. Direct sediment -laden water onto the naturally vegetated or stabilized planted ground.
6. Do not place any equipment, construction debris, or extra soil in the buffer area.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Keeping
vegetation healthy in a recently established buffer requires routine maintenance, which (depending on species,
soil types, and climatic conditions) may include weed control, fertilizing, liming, and irrigating. Once
established or if using a naturally vegetated area, buffers do not require much maintenance beyond repairing
or replacing damaged vegetation. Inspections should focus on encroachment, gully erosion, density of
vegetation, evidence of concentrated flows through the areas, and any damage from foot or vehicular traffic. If
there is more than 6 inches of sediment in one place, it should be removed.
Removal
During final site cleanup, any barriers placed around preserved natural areas should be removed.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
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VB -2
June 2008
Wattles (W)
Description
A wattle (also called a fiber roll) consists of straw, flax, or other similar materials bound into a tight tubular roll.
Excelsior log (aspen fiber) is the preferred wattle. When wattles are placed at the toe and on the face of
slopes, they intercept runoff, reduce its flow velocity, release the runoff as sheet flow, and provide removal of
sediment from the runoff. By interrupting the length of a slope, fiber rolls can also reduce erosion.
Applicability
Wattles may be suitable:
• As slope breakers along the toe, top, face, and at grade breaks of exposed and erodible slopes to
shorten slope length, reduce runoff velocity, and spread runoff as sheet flow
• At the end of a downward slope where it transitions to a steeper slope
• Along the perimeter of a project
• At the overflow locations of sediment traps
• As check dams in unlined ditches
• Around temporary stockpiles
Limitations
• Wattles are not effective unless trenched.
• Wattles placed directly at the toe of slopes greater than 5:1 (H:V) should be a minimum of 20 -in.
diameter or installations achieving the same protection (i.e. stacked smaller diameter wattles, etc.).
• Difficult to move once saturated.
• If not properly staked and trenched in, wattles could be transported by high flows.
• Wattles have a very limited sediment capture zone.
• Wattles should not be used on slopes subject to creep, slumping, or landslide.
• Wattles should not be used where periodic road or surface maintenance activities are expected.
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W-1
June 2008
Design criteria
No formal design is required.
Construction specifications
Wattles should be either prefabricated rolls or rolled tubes of erosion control blanket. (If using an erosion
control blanket, roll the length of erosion control blanket into a tube of minimum 8 in. diameter and bind roll at
each end and every 4 ft along length of roll with jute -type twine.)
See Figure W-1 for wattles used to control erosion along slopes.
1. Locate wattles on level contours spaced as follows:
a. Slope inclination of 4:1 (H:V) or flatter: Fiber rolls should be placed ata maximum interval of
20 ft.
b. Slope inclination between 4:1 and 2:1 (H:V): Fiber Rolls should be placed at a maximum
interval of 15 ft. (a closer spacing is more effective).
c. Slope inclination 2:1 (H:V) or greater: Fiber Rolls should be placed at a maximum interval of 10
ft. (a closer spacing is more effective).
2. Turn the ends of the wattles up slope to prevent runoff from going around the roll.
3. Stake wattles into a 2 to 4 in. deep trench with a width equal to the diameter of the wattle. Drive
stakes at the end of each wattle and spaced 4 ft maximum on center. If wattles are part of a layered
BMP system (3 or more) and a vegetated buffer (VB) is used, the wattles may be staked without
trenching. Staking must insure continuous contact with the ground.
4. If more than one wattle is placed in a row, the rolls should be overlapped, not abutted.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Repair or
replace split, torn, unraveling, or slumping rolls. If the wattle is used as a sediment capture device, or as an
erosion control device to maintain sheet flows, sediment that accumulates must be periodically removed in
order to maintain wattle effectiveness. Sediment should be removed when sediment accumulation reaches
one-half the designated sediment storage depth, usually one-half the distance between the top of the wattle
and the adjacent ground surface.
Removal
Wattles are typically left in place. If wattles are removed, collect and dispose of sediment accumulation, and fill
and compact holes, trenches, depressions or any other ground disturbance to blend with adjacent ground.
References
California Stormwater Quality Association, Stormwater Best Management Practice (BMP) Handbook —
Construction. January, 2003. <http://www.cabmphandbooks.com/Construction.asp>
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W-2
June 2008
Figure W-1
Wattle Installation
Irlall wattle neer
sings wham it
Iruha?liuwa• i rrlu
slesp9' slope
Verncsl w,smng mo-asurutl ulcng mc, 'ace
1 the siva cense betreisq 1Cr grid 23:2
NOT TO SCALE
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W-3
Nule Install walna a lba lare140a4Pdr.
Exiand and of wattlsugsiopgb
amid flow arwrrd acrd.
June 2008
Drainage Control BMPs
Berm (B)
Culvert (C)
Culvert Inlet Protection (CIP)
Culvert Outlet Protection (COP)
Diversion (D)
Drainage Dip (DD)
Level Spreader (LS)
Roadside Ditches (RSD) and Turnouts (TO)
Run -On Diversion (ROD)
Slope Drain (SD)
Trench Breaker (TB)
Water Bar (WB)
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June 2008
Berm (B)
Description
A berm is a ridge of compacted soil located at the top or base of a sloping disturbed area to contain or divert
surface runoff. Berms may be constructed from either excavated topsoil or subsoil.
The purpose of a berm is to control runoff velocity, divert on-site surface runoff to a sediment trapping device,
and/or divert clean water away from disturbed areas.
Applicability
Berms are usually appropriate for drainage basins smaller than 5 acres, but with modifications they can be
capable of servicing areas as large as 10 acres. With regular maintenance, earthen berms have a useful life
span of approximately 18 months. Berms are applicable for the following applications:
• At the perimeter of a well pad (particularly the outer edge) to ensure that runoff remains on the pad
and is diverted to a well pad detention pond, if available. See Detention Pond (DP).
• Along the outside shoulder of an insloped road to ensure that runoff from the roadway drains inward
and to protect the fill slope from continual disturbances during road blading and maintaining. See
Land Grading (LG) — Roads.
• Upslope of cut or fill slopes to divert flows away from disturbed areas.
• Downslope of cut or fill slopes to divert on-site runoff to a stabilized outlet or sediment trapping device,
although diversions are more commonly used for this application. See Diversion (D).
• As temporary slope breakers to reduce runoff velocity and divert water off the construction right-of-
way.
Limitations
• Berms may erode if not properly compacted and stabilized with vegetation or an erosion control
blanket. Berms which are adjacent to concentrated flows will require erosion blanketing according to
Erosion Control Blanket (ECB).
• If a berm crosses a vehicle roadway or entrance, its effectiveness can be reduced. Wherever
possible, berms should be designed to avoid crossing vehicle pathways.
Design criteria
No formal design is required.
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B-1
June 2008
Construction specifications
1. Prior to berm construction, remove all trees, brush, stumps, and other objects in the path of the berm
and till the base of the berm before laying the fill. Fill may consist of topsoil or subsoil excavated
during the construction of nearby roads or well pads. If fill material is excavated adjacent to berm,
follow the specification for Diversion (D).
2. Construct the berm according to Figure B-1 for the appropriate drainage area. For points where
vehicles will cross the berm, the side slope should be no steeper than 3:1 and the mound may be
constructed of gravel rather than soil. This will prolong the life of the berm and increase effectiveness
at the point of vehicle crossing. For well pad perimeter installation the pad side of the berm should be
sloped at 1.5:1 to help prevent vehicles from backing over the edge of the pad.
3. To remain effective, berms should be compacted with tracked equipment, if possible.
4. All berms shall have positive drainage to a stabilized outlet so that runoff does not collect in ponds on
the upslope side of the berm, but instead flows along the berm until it reaches a stabilized outlet. Field
location should be adjusted as needed. Stabilized outlet may be a well -vegetated area, a well pad
detention pond, or a sediment control such as a silt fence or a sediment trap where sediment can
settle out of the runoff before being discharged to surface waters.
5. If the expected life span of the berm is greater than 15 days, it is strongly recommended that the berm
be stabilized with vegetation or an erosion control blanket immediately after construction. Stabilization
is required where concentrated flows are expected. See Table B-1 for recommended stabilization
methods for berms on various slopes.
6. Berms should be constructed and fully stabilized prior to commencement of major upslope land
disturbance. This will maximize the effectiveness of the structure as a stormwater control device.
7. If using berms as temporary slope breakers to reduce runoff velocity, space the berms according to
the following table:
Slope (%)
Spacing (feet)
5 —15
300
>15 — 30
200
>30
100
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Berms should
be inspected for evidence of erosion or deterioration to ensure continued effectiveness. Berms should also be
maintained at the original height. Any decrease in height due to settling or erosion, which impacts the
effectiveness of the BMP, should be repaired immediately.
Removal
Berms should remain in place and in good condition until all upslope disturbed areas are permanently
stabilized. There is no need to formally remove the berm on completion of stabilization until interim or final
reclamation.
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June 2008
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
http://www.dec.state.ny.us/website/dow/toolbox/escstandards
Table B-1
Temporary Berm Stabilization
Type of Treatment
Channel Grade'
A (<5 Ac.)
B (5-10 Ac)
1
0.5-3.0%
Seed & Straw Mulch
Seed & Straw Mulch
2
3.0-5.0%
Seed & Straw Mulch
Seed and cover with
erosion control blanket,
or lined with 2 -inch stone
3
5.0-8.0%
Seed and cover with
erosion control blanket,
or line with 2 -inch stone
Line with 4 to 8 -inch
stone or rock2
4
r 8.0-20.0%
Line with 4 to 8 -inch or
stone or rock2
Engineering Design
Notes:
1 In highly erodible soils, as defined by the local approving agency, refer to the next higher slope grade for
type of stabilization.
2 Site rock if available, shall be broken into the required size.
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June 2008
Figure B-1
Berm Installation
TYPE A - GENERAL SITE PERIPAETER INSTALLATION
5iP as 1,x°5 rnk�
Sled112a1nm F require.1 (Fos takee) On
stoop slopes oxratalc La pravult
requraad 1lrlta width at now alcplh
N(11 TO tiCN_
Slap* I'?a ton. -*
NOT TO SCALE
B
Max 2
7 1
O A
NrRn, Shale^_ I.4 rm 13 5`k ID .4`•'.. I><I
slalnlic*c ILt:L
2 Mala. Cut cr FIA Slope
1
Natural gratirKIsurlacxi
BERM A BERME
icy acs 111 ace
A - F1ERti WEIGHT 1@ r= 36 an
6. -BERM WIDTH 24 J. 36m
C-FLCAA"WIDTH AB in 60 St
-FWLQWIMPH can Is in
TYPE B - WELL PAD PERIMETER INSTALLATION
Ma°a 1.5
Stabilization as 'squired (sae table).
War Slope Nam 0 V t4 11O% IO
dataaeliraaa perxl
2�.
2#•
2 Max,
Well Pbd Cur or Fdl
FnII {Tolril or SLSaI I
TYPE O - ROADSIDE INSTALLATION
PJOT TO SCALE
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June 2008
Culvert (C)
Description
Culverts are typically concrete, steel, aluminum, or plastic pipe used to move ditch water under the road or to
direct stream flow under the road or construction area.
Applicability
Culverts are ideal on road grades less than 15%. For grades over 15%, it is difficult to slow down the water or
remove it from the road surface rapidly. On such steep grades, it is best to use frequently spaced relief
culverts and drainage crossing culverts with armored ditches. Culverts may be used in the following
applications:
• As drainage crossing culverts in streams and gullies to allow normal drainage to flow under the
traveled way.
• As ditch relief culverts to periodically relieve the inside ditch line flow by piping water to the opposite
side of the road where the flow can be dispersed away from the roadway. Culverts placed in natural
drainages may be utilized for ditch relief.
Limitations
• If undersized, culverts are susceptible to plugging and require cleaning.
• Culverts will not filter sediment.
• Culverts are easily crushed if not properly designed.
Design criteria
Capacity
All culverts should be designed for a minimum 25 -year -frequency storm with an allowable head that does not
overlap the roadway. However, the minimum acceptable size culvert diameter to prevent failure from debris
blockage is 18 inches for intermittent stream crossings and 36 inches for perennial stream crossings. Pipe
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C-1
June 2008
size can be determined using general design criteria, such as in Table C-1, but is ideally based upon site-
specific hydrologic analysis.
Depth
The depth of culvert burial must be sufficient to ensure protection of the culvert barrel for the design life of the
culvert. This requires anticipating the amount of material that may be lost due to road use and erosion.
Headwalls
Use headwalls on culvert pipes as often as possible (see Retaining Wall (RW)). The advantages of headwalls
include: preventing large pipes from floating out of the ground when they plug; reducing the length of the pipe;
increasing pipe capacity; helping to funnel debris through the pipe; retaining the backfill material; and reducing
the chances of culvert failure if it is overtopped.
Construction specifications
Drainage crossing culverts
1. Make road crossings of natural drainages perpendicular to the drainage to minimize pipe length and
area of disturbance (Figure C-1).
2. Use single large pipes versus multiple smaller diameter pipes to minimize plugging potential in most
channels (unless roadway elevation is critical). In very broad channels, multiple pipes are desirable to
maintain the natural flow spread across the channel. All culverts should be concrete, corrugated metal
pipe (CMP) made of steel or aluminum, or properly bedded and backfilled corrugated plastic pipe.
3. Align culverts in the bottom and middle of the natural channel flowline so that installation causes no
change in the stream channel alignment or stream bottom elevation. Culverts should not cause
damming or pooling or increase stream velocities significantly.
4. Extend the outlet of the culvert at least 1 foot beyond the toe of the slope to prevent erosion of the fill
material. Alternatively, use retaining walls (headwalls) to hold back the fill slope.
5. It may be necessary to install riprap, erosion control blanketing, a combination of the riprap and
blanketing, or other energy dissipater device at the outlet end of the culvert to reduce soil erosion or to
trap sediment (see Culvert Outlet Protection (COP)).
6. It may be desirable to construct pulloffs/turnouts for vehicles on one or both sides of narrow culvert
crossings. This will help avoid culvert crushing as well as disturbance to roadside ditches and berms.
Ditch relief culverts
1. See Figure C-2 for installation details.
2. Ditch relief culverts can provide better flow when skewed 0 to 30 degrees perpendicular to the road.
3. The culvert gradient should be at least 2% greater than the approach ditch gradient. This improves
the flow hydraulics and reduces siltation and debris from plugging the culvert inlet.
4. Discharge culvert at natural ground level where possible (see Figure C 3 Type A), on firm, non-erosive
soil or in rocky or brushy areas. If discharged on the fill slopes, armor outlets with riprap or slash (see
Figure C-3 — Type B), or use down -drain structures (see Figure C-3 — Type C and Slope Drain (SD)).
5. Extend the inlet of the culvert at least 1 foot beyond the flowline of the roadside ditch. Extend the
outlet of the culvert at least 1 foot beyond the toe of slopes to prevent erosion of the fill material.
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June 2008
6. It may be necessary to install riprap or other energy dissipater devices at the outlet end of the culvert
to prevent soil erosion or to trap sediment (see Culvert Outlet Protection (COP)).
7. Spacing of culverts is dependent on the road gradient, soil types, and runoff characteristics according
to the following table:
Soil type
Road grade
2-4%
5-8%
9-12%
Highly corrosive granitic or sandy
240'
180'
140'
Intermediate erosive clay or load
310'
260'
200'
Low erosive shale or gravel
400'
325'
250'
8. It may be desirable to construct pulloffs/turnouts for vehicles on one or both sides of narrow culvert
crossings. This will help avoid culvert crushing as well as disturbance to roadside ditches and berms.
Backfill and compaction
1. See Figure C-4.
2. Firmly compact well -graded fill material (soil or road base) around culverts, particularly around the
bottom half, using placement in layers to achieve a uniform density. Use slightly plastic sandy gravel
with fines. Avoid the use of fine sand and silt rich soils for bedding material because of their
susceptibility to piping. Pay particular attention to culvert bedding and compaction around the
haunches of the pipe. Do not allow the compaction to move or raise the pipe. In large fills, allow for
settlement.
3. Cover the top of metal and plastic culvert pipes with fill to a depth of at least 1 foot to prevent pipe
crushing by heavy trucks. Use a minimum cover of 2 feet of fill over concrete pipe. For maximum
allowable fill height, follow the manufacturer's recommendations.
4. Mound fill over the top of culvert pipes so that the road is slightly raised at culvert locations to help
prevent erosion and water from ponding over culvert crossings. This practice, as well as placing large
boulders around the culvert outlets, will also help to prevent culverts from crushing.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. If any damage
to culvert or inlet/outlet protection is noted or if there is any evidence of scour, repairs should be made
immediately. Any debris that may be blocking the culvert inlet or outlet should be removed.
References
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
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June 2008
United States Department of the Interior and United States Department of Agriculture. Surface Operating
Standards and Guidelines for Oil and Gas Exploration and Development "Gold Book". BLM/WO/ST-
06/021+3071. Bureau of Land Management (BLM). Denver, Colorado. Fourth Edition, 2006.
Table C-1
Culvert Sizing
Drainage Area
(acres)
Size of Drainage Structure (diameter and area)
Steep Slopes
(Light Vegetation)
C=0.7
Gentle Slopes
(Heavy Vegetation)
C=0.2
Round Pipe
(in)
Area
(sq. ft)
Round Pipe
(in)
Area
(sq. ft)
0 —10
30"
4.9
18"
1.8
10 - 20
42"
9.6
24"
3.1
20 - 35
48"
12.6
30"
4.9
35 - 75
72"
28.3
42"
9.6
75 - 125
84"
38.5
48"
12.6
125 - 200
96"
50.3
60"
19.6
Notes: If pipe size is not available, use the next larger pipe size for the given drainage area. For intermediate terrain,
interpolate between pipe sizes. Pipe size is based upon the Rational Formula and Culvert Capacity curves.
Assumes a rainfall intensity of 3 to 4 in/hr. Values of "C" are the Runoff Coefficients for the terrain.
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June 2008
Figure C-1
Drainage Crossing Culvert Alignment & Overflow Dip
Noe. Make road crossing perper sr Is)
inn drainage -in neairnizn pipe Iorgrh
and area or elts[urterre.
NOT TO SCALE
Turnout when)
crossings are
nsrrrrr,
Fill
Figure C-2
Ditch Relief Culvert Installation
t^day[ prnlodion ar .ir ixli, !
Spac!ng 110-11:Ce
bnMwncn culvaerrs
L9u[le1 protBcarxii
antis Amp
Roadsde ditch
ExIonn cllvr}n al IRas1 9` kiR'graand
the 1loelrne of Pie roadelde diM1r
Intel pro[ac6on as nestled
Extend cul,rnn
1" Beyond toed slope
NOT TO SCALE
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Fill gape
Place const paps al natural ground
Israel ar romp aurae( the till raaterial
C-5
June 2008
Figure C-3
Culvert Installation Options
TYPE A
Natural ground surtax
Roar/hod
-- Inskpw 3-5% Comparted
Fill
Culvert
Cog Alain
Culvert
TYPE
CuIverl
NOT TJ SCALE
SIlght mound aver cul•eurl
Roadbed
Base and slrieewall Ffr rnlle.rral
shutud bre: rpmpaclrr.. Cnrnpact
the fill a minium of each culvert
diampler on each sem of trio
wlverl.
NOT TO SCALE
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Rrladbad
Insrcpe 3-5.%
TYPE B
r
Culvert
Cadet proteCon
with rock rfprap
aaarrd
Inslcpa 3-5%
Compacted Fill
Add riprap or (idler
ape protedion
QartIm1 pro!daon
wrlh roc* rrpraQ
.canpaaled Fla
Anchor the elope drain pie to the lilt slope
walIi stakie3, rah1e anchor bkeiir.s, errs.
Cutlet protection
with rock riprap
Figure C-4
Culvert Backfill and Compaction
d0'
C-6
At tease 1 1t. or cover for CN1P rr
Ma third cr diaeniet er Fur large
culvarls Use 2 ttcover for
concerto pipe.
CU! ail
Tamp backfill malarial at
regualarmtervals tIrlt Of G -r
Level ail natural slreambed
Gra•.e1(sr Mil culvert. bed
Elea rMk larger than 3.)
June 2008
Culvert Inlet Protection (CIP)
Description
Culvert protection is required at both the inlet to the culvert (upstream side) and the outlet to the culvert
(downstream side).
Culvert inlet protection may involve placing boulders, riprap, gabions, rock retaining walls, slash, and/or any
other protection at the inlets of pipes. Riprap, or other energy -dissipating devices, will reduce the velocity of
stormwater flows and thereby prevent erosion and help protect the inlet structure.
Applicability
Riprap inlet protection should be used where velocities and energies at the inlets of culverts are sufficient to
erode around the inlet structure. Riprap may also be used to help channel the stormwater to the inlet of the
culvert.
Design criteria
Riprap, gabions, or rock retaining walls at culvert inlets shall be designed according to their appropriate BMPs.
Construction specifications
Figure CIP-1 shows typical culvert inlet protection. However, site specifics shall dictate actual design.
1. Riprap, gabions, or rock retaining walls at culvert inlets shall be constructed according to their
appropriate BMPs.
2. After installation of a culvert, examine the stream channel for the amount of debris, logs, and brushy
vegetation present. In channels with large amounts of debris, consider using oversized pipes.
3. Boulders should be drystacked around the culvert inlet and up the slope to the edge of the road.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspect for
debris at the entrance to culverts and within culverts. Inspect riprap at culvert inlets for damaged or dislodged
stones. Any needed repairs that reduce the effectiveness of the BMP should be made immediately.
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CIP-1
June 2008
References
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
Figure CIP-1
Typical Inlet Protection
/ F
Acrid ruNsirl
I _ _ rrr 1` tliaraidirec# sPape
S"
4.116100.
"S dirnLWp
Trap
R°ad Ja diltri
NOT TO SCALE
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Rpxap CRJ °T
Erosion control
IA:inknl iEO )
CIP-2
f
June 2008
Culvert Outlet Protection (COP)
Description
Culvert protection is required at both the inlet to the culvert (upstream side) and the outlet to the culvert
(downstream side).
Culvert outlet protection involves placing structurally lined aprons or other appropriate energy -dissipating
devices, such as large boulders or plunge pools, at the outlets of pipes to reduce the velocity of stormwater
flows and thereby prevent scouring at stormwater outlets, protect the outlet structure, and minimize potential
for erosion downstream.
Applicability
Culvert outlet protection should be used where discharge velocities and energies at the outlets of culverts or
channels are sufficient to erode the next downstream reach.
Limitations
Rock aprons at culvert outlets should not be placed on slopes steeper than 10 percent. Runoff from pipe
outlets at the top of cuts/fills or on slopes steeper than 10 percent should be routed via slope drains or riprap
chutes to a rock apron at the toe of the slope. Otherwise flows will re -concentrate and gain velocities as the
flow leaves the apron.
Design criteria
Gabions or rock retaining walls at culvert outlets shall be designed according to their appropriate BMPs. No
formal design is required for plunge pools at outlets. Riprap aprons at culvert outlets shall be designed as
follows:
Tailwater depth. The depth of tailwater immediately below the pipe outlet must be determined for the design
capacity of the pipe. If the tailwater depth is less than half the diameter of the outlet pipe, and the receiving
stream is wide enough to accept divergence of the flow, it shall be classified as a Minimum Tailwater
Condition. If the tailwater depth is greater than half the pipe diameter and the receiving stream will continue to
confine the flow, it shall be classified as a Maximum Tailwater Condition. Pipes which outlet onto flat areas
with no defined channel may be assumed to have a Minimum Tailwater Condition.
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COP -1
June 2008
Riprap apron size & D50. The apron length (LA) and the D50 of the riprap shall be determined from
Table COP -1 according to the design flow and whether there is a minimum or maximum tailwater condition.
The apron width (W) shall then be determined as:
W = d + 0.4 LA
where d is the diameter of the culvert.
If the pipe discharges directly into a well defined channel, the apron shall extend across the channel bottom
and up the channel banks to an elevation 1 foot above the maximum tailwater depth or to the top of the bank,
whichever is less. The upstream end of the apron, adjacent to the pipe, shall have a width two (2) times the
diameter of the outlet pipe, or conform to pipe end section if used.
Riprap materials. The outlet protection may be done using rock riprap or grouted riprap. Riprap shall be
composed of a well -graded mixture of stone size so that 50 percent of the pieces, by weight, shall be larger
than the D50 size determined from Table COP -1. A well -graded mixture, as used herein, is defined as a
mixture composed primarily of larger stone sizes, but with a sufficient mixture of other sizes to fill the smaller
voids between the stones. The diameter of the largest stone size in such a mixture shall be 1.5 times the D50
size. All grout for grouted riprap must be one part Portland cement for every 3 parts sand, mixed thoroughly
with water.
Filter. If a filter cloth or gravel is used, it should be designed according to Riprap (R).
Apron thickness. The minimum thickness of the riprap layer shall be 1.5 times the maximum stone diameter
for D50 of 15 inches or less; and 1.2 times the maximum stone size for D50 greater than 15 inches.
Riprap stone quality. Stone for riprap shall consist of field stone or rough unhewn quarry stone. The stone
shall be hard and angular and of a quality that will not disintegrate on exposure to water or weathering. The
specific gravity of the individual stones shall be at least 2.5. Site rock or site boulders may be used provided it
has a density of at least 150 pounds per cubic foot, and does not have any exposed steel or reinforcing bars.
Construction specifications
Gabions or rock retaining walls at culvert outlets shall be constructed according to their appropriate BMPs.
Riprap aprons at culvert outlets shall be constructed according to Figure COP -1 and as follows:
1. Prepare the subgrade for the riprap to the required lines and grades. Any fill required in the
subgrade shall be compacted to a density of approximately that of the surrounding undisturbed
material.
2. If a pipe discharges into a well-defined channel, the channel's side slopes may not be steeper
than 2:1.
3. Construct apron to the design length and width with no slope (Figure COP -1). The invert
elevations must be equal at the receiving channel and the apron's downstream end. No overfall at
the end of the apron is allowed. The elevation of the downstream end of the apron shall be equal
to the elevation of the receiving channel or adjacent ground. The outlet protection apron shall be
located so that there are no bends in the horizontal alignment.
4. Line the apron with riprap, grouted riprap, or concrete. Riprap should be the appropriate size and
thickness as designed. See Riprap (R) for the placement of riprap.
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COP -2
June 2008
5. If a culvert outlets at the top of cuts/fills or on slopes steeper than 10 percent one of the following
two options is suggested:
a. Transition culvert to a slope drain according to Slope Drain (SD). The slope drain shall
convey stormwater to the bottom of the slope where a riprap apron, as designed above,
shall prevent erosion at the slope drain outlet.
b. Line slope below culvert outlet with a riprap channel to convey stormwater to the bottom
of the slope where a riprap apron, as designed above, shall prevent erosion at the
bottom of the slope. The riprap channel shall be designed according to the table in the
Riprap (R) BMP that is based on depth of flow and slope. The riprap channel shall dip
into the slope so that all water is contained within the channel, flows to the riprap outlet
apron at the base of the slope, and does not spill over the sides onto unprotected soil.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. The
maintenance needs are usually very low for properly installed riprap aprons at culvert outlets. However,
inspect for evidence of scour beneath riprap at outlet aprons or for dislodged stones. And needed repairs that
reduce the effectiveness of the BMP should be made immediately.
References
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
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COP -3
June 2008
Table COP -1
Outlet Protection Design
Riprap Aprons for Law TiaMater
(downstream flow death < 0.5 x pipe diameter)
Caved
est 'fie
E+1'.a fl mit,-3f�P J3!°
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COP -4
June 2008
Figure COP -1
Typical Outlet Protection
A
w = d$0.416
d —
1.5xa...
pr 1 a CAR.,,
2
Graded aggregale
11Iter ur NW da111
Graders antsrowte
tiller or lillat cloth
La
NOT TO SCALE
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COP -5
June 2008
Diversion (D)
Definition
A diversion is a drainage way of parabolic or trapezoidal cross section with a supporting ridge on the lower
side that is constructed across the slope. The purpose of a diversion is to prevent off-site storm runoff from
entering a disturbed area, to prevent sediment laden storm runoff from leaving the construction site or
disturbed area, to prevent flows from eroding slopes, and to direct sediment laden flows to a trapping device.
Applicability
Diversions may be designed for temporary or permanent use. The maximum drainage area for temporary,
un -compacted diversions is 2 acres. For drainage areas larger than 2 acres but less than 10 acres, the
diversion should be compacted. For undisturbed drainage areas larger than 10 acres, a permanent diversion
may be designed to handle larger flows. Diversions may be used for the following applications:
• Upslope of cut or fill slopes to convey or divert flows away from disturbed areas. See Run -On
Diversion (ROD).
• Down-slope of cut or fill slopes to divert on-site runoff to a stabilized outlet or sediment trapping
device.
• At the outer edge of a well pad to ensure that runoff remains on the pad and is diverted to a well pad
detention pond, if available. See Detention Pond (DP).
• Where runoff from higher areas has potential for causing erosion, or interfering with, or preventing the
establishment of, vegetation on lower areas.
• Where the length of slopes needs to be reduced so that soil loss will be kept to a minimum.
• At the perimeter of a site or disturbed area.
Limitations
• The area around the diversion channel that is disturbed by its construction must be stabilized (with
vegetation or other erosion control) so that it is not subject to similar erosion as the steep slope the
channel is built to protect.
• To alleviate erosion capability, diversions must be directed into a stabilized outlet or well -vegetated
area or to sediment trapping devices, where erosion sediment can settle out of the runoff before being
discharged to surface waters.
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D-1
June 2008
• Temporary diversions should be designed to avoid crossing vehicle pathways.
• Diversions should be used with caution on soils subject to slippage.
Design criteria
For a temporary diversion (drainage area less than 10 acres), no formal design is necessary. For a run-on
diversion see the Run -On Diversion (ROD) BMP. For other permanent diversions (drainage area larger than
10 acres) the following guidelines apply:
Location
Diversion location shall be determined by considering outlet conditions, topography, land use, soil type, length
of slope, and the development layout.
Capacity
Peak rates of runoff values used in determining the capacity requirements shall be as outlined by TR -55,
Urban Hydrology for Small Watersheds. The constructed diversion shall have capacity to carry, as a
minimum, the peak discharge from a 10 -year frequency rainfall event with freeboard of not less than 0.3 feet.
Cross section
See Figure D-2 for details. The diversion channel shall be parabolic or trapezoidal in shape, if possible. The
diversion shall be designed to have stable side slopes. The side slopes shall not be steeper than 2:1 and shall
be flat enough to ensure ease of maintenance of the diversion and its protective vegetative cover. The ridge
shall have a minimum width of 4 feet at the design water elevation; a minimum of 0.3 feet freeboard and a
reasonable settlement factor (10%) shall be provided.
Velocity and grade
The permissible velocity for the specific soil type will determine the maximum grade. The maximum
permissible velocity for sand and silt vegetated channels is 3 ft/sec, and 5 ft/sec for clay vegetated channels.
Diversions are not usually applicable below high sediment producing areas unless structural measures,
designed to prevent damaging accumulations of sediment in the channels, are installed with, or before, the
diversions.
Construction specifications
General
1. All trees, brush, stumps, obstructions, and other objectionable material shall be removed and
disposed of so as not to interfere with the proper functioning of the diversion.
2. All diversions shall have uninterrupted positive grade to an outlet.
3. Each diversion must have an adequate outlet where outflow will not cause damage. Diverted
runoff from a disturbed area shall be conveyed to a sediment trapping device. Diverted runoff
from an undisturbed area shall outlet to a sediment trapping device or into an undisturbed
stabilized area at non-erosive velocities. Vegetated outlets shall be installed before diversion
construction, if needed, to ensure establishment of vegetative cover in the outlet channel.
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D-2
June 2008
Temporary diversion (drainage area <10 acres)
See Figure D-1.
1. The diversion shall be excavated or shaped to line, grade, and cross section as required to meet
the specified criteria. The diversion does not need to be compacted if the contributing drainage
area is less than 2 acres.
2. Stabilization with vegetation is not required as long as sediment traps or other sediment control
devices are provided.
Permanent diversion (drainage area >10 acres)
See Figure D-2.
1. The diversion shall be excavated or shaped to line, grade, and cross section as required to meet
the criteria specified herein, and be free of bank projections or other irregularities which will
impede normal flow.
2. Parabolic and triangular-shaped, grass -lined channels should not have a top width of more than
30 feet. Trapezoidal, grass -lined channels may not have a bottom width of more than 15 feet
unless there are multiple or divided waterways, they have a riprap center, or other methods of
controlling the meandering of low flows are provided.
3. If grass -lined channels have a base flow, a stone center or subsurface drain or another method for
managing the base flow must be provided.
4. Fills shall be compacted as needed to prevent unequal settlement that would cause damage in
the complete diversion.
5. All earth removed and not needed in construction shall be spread or disposed of on the
construction side of the diversion so that it will not interfere with the functioning of the diversion.
6. Immediately after the ridge and channel are constructed, they must be seeded or hydro -seeded
and mulched according to Revegetation (RV) and Mulching (M) or Erosion Control Blanket (ECB)
along with any disturbed areas that drain into the diversion.
a. For design velocities less than 3.5 ft/sec, seeding and mulching may be used for
establishment of the vegetation. It is recommended that, when conditions permit,
temporary diversions or other means should be used to prevent water from entering the
diversion during the establishment of the vegetation.
b. For design velocities of more than 3.5 ft/sec, the diversion shall be stabilized with seeding
protected by Jute or Excelsior matting, or with seeding and mulching until the vegetation is
established.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Channels
should be cleared of sediment, repairs made when necessary, and seeded areas reseeded if a vegetative
cover is not established. Maintain diversion capacity, ridge height, and outlet elevations especially if high
sediment yielding areas are in the drainage area above the diversion. Establish necessary cleanout
requirements. Redistribute sediment as necessary to maintain the capacity of the diversion.
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D-3
June 2008
Removal
Temporary and un -compacted diversions shall remain in place only until the disturbed areas are permanently
stabilized. Permanent diversions shall remain in place until final reclamation.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), Field
Office Technical Guide. 2002. <www.nrcs.usda.gov/technical/efotg>
5mal'. pression In
Capture R;irCA1 him
nrrr r r..Y Jircfsinn
NOT TO SCALE
Figure D-1
Temporary Diversion Installation
24' mu
8' rain
Figure D-2
Permanent Diversion Installation
FLOW
DaeIgn Top W Th — Max 1
llgsign Depth 2
Mu., 2 vtammia.10"
— 15'max —
fifir it SCA...E
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Flory
L
Nr:
1) E1wy'ersion shall slopo bolwoon
9.5% and a% la a slablitea male!.
2}EIi'.aesn[>e'rsIP_tiledet ,e or 1,8104+
wall parrs Shan halo a vocgoralod
butler beaver' Vie diovraiurr and
the Fred. it pyba,b4ii.
48' min. —
i r SeI einerrl
.1
D-4
F41 ramal
r min. Froebixard'
Srabiliro with V'og,nlaloan
aril Mulrh or Erosion
C 1n1rnl eLa nkol
1 M.
StnaiIl derferssion ba
Ceplur Runoff from
ammo/ Diversion
2
June 2008
Drainage Dip (DD)
Description
Drainage dips intercept and remove surface water from the road and shoulders before the combination of
water volume and velocity begins to erode the surface materials. Drainage dips are constructed diagonally
across and as part of the road surface, and will pass slow traffic while dispersing surface water.
Applicability
Drainage dips may be used in the following applications:
• To move water off the road surface efficiently and economically
• In place of a culvert, which is costly and susceptible to plugging or failure
• On low volume, low to moderate speed roads (10-35 mph) with grades less than 12%
Limitations
• Size limited by the safe passage of trucks and equipment
• May cause concentrated flows from sheet flows
• Requires vegetative cover or other sediment filter/trap at discharge point
Design criteria
No formal design required.
Construction specifications
See Figure DD -1.
1. Construct rolling dips deep enough to provide adequate drainage, angled 0-25 degrees from
perpendicular to the road, with a 3-5% outslope, and long enough (50 to 200 feet) to pass vehicles
and equipment.
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DD -1
June 2008
2. In soft soils, armor the mound and dip with gravel or rock, as well as the outlet of the dip.
3. Spacing of drainage dips depends upon local conditions such as soil material, grade, and topography.
See Table DD -1 for recommended maximum distances between drainage dips.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspections
should pay close attention to discharge points.
References
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
Maine Department of Conservation, Best Management Practices for Forestry: Protecting Maine's Water
Quality. Maine Forest Service, Forest Policy and Management Division. Augusta, Maine. 2004.
<http://www.state.me.us/doc/mfs/pubs/pdf/bmp_manual/bmp_manual.pdf>
United States Department of the Interior and United States Department of Agriculture. Surface Operating
Standards and Guidelines for Oil and Gas Exploration and Development "Gold Book". BLM/WO/ST-
06/021+3071. Bureau of Land Management (BLM). Denver, Colorado. Fourth Edition, 2006.
Table DD -1
Maximum Distance between Drainage Dips
Road Grade, %
Low to
Non -Erosive Soils (1)
Erosive Soils (2)
0 - 3
400'
200'
4 - 6
300'
160'
7 - 9
250'
130'
10 - 12
200'
110'
12+
160'
100'
(1) Low Erosion Soils = Coarse Rocky Soils, Gravel, and Some Clay
(2) High Erosion Soils = Fine, Friable Soils, Silt, Fine Sands
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DD -2
June 2008
Figure DD -1
Typical Drainage Dip
1
a
kneel Grade [
2% 10.
4% 14*
6% 16'
6% zr
ry Mound
NOT TO SCALE
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D D-3
June 2008
Level Spreader (LS)
Description
A level spreader is a device used to prevent erosion and to improve infiltration by spreading concentrated
stormwater runoff evenly over the ground as shallow flow instead of through channels. It usually involves a
depression in the soil surface that disperses flow onto a flatter area across a slight slope and then releases the
flow onto level vegetated areas. This reduces flow speed and increases infiltration.
Applicability
A level spreader is most effective for a contributing area less than 5 acres in size and slopes no steeper than
2:1. Level spreaders may be used where:
• Sediment -free storm runoff can be released in sheet flow down a stabilized slope without causing
erosion.
• A level lip can be constructed without filling.
• The area below the level lip is uniform with a slope of 10% or less and the runoff will not re -
concentrate after release.
• No traffic will be allowed over the spreader.
Limitations
This practice applies only in those situations where the spreader can be constructed on undisturbed soil and
the area below the level lip is uniform with a slope of 10% or less and is stabilized by natural vegetation. The
runoff water should not be allowed to reconcentrate after release unless it occurs during interception by
another measure (such as a detention basin) located below the level spreader.
Design criteria
Capacity
The design capacity shall be determined by estimating the peak flow from the 10 -year storm. The drainage
area shall be restricted to limit the maximum flows into the spreader to 30 cubic feet per second (cfs).
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LS -1
June 2008
Construction specifications
See Figure LS -1 for details.
1. A transition section will be constructed from the diversion channel to the spreader to smoothly
blend the different dimension and grades.
2. The level lip will be constructed in undisturbed soil to a uniform height and zero grade over the
length of the spreader. For design flows less than 5 cfs, a vegetated level lip may be constructed
with an erosion -resistant material, such as jute or excelsior blankets, to inhibit erosion and allow
vegetation to become established. The matting should be a minimum of 4 ft. wide extending
6 inches over the lip and buried 6 inches deep in a vertical trench on the lower edge.
3. For design flows higher than 5 cfs and permanent installations, a rigid level lip of non -erodible
material, such as site rock and gravel, should be used.
4. The runoff will be discharged onto a stabilized and generally smooth vegetated slope not
exceeding 10%.
5. Seed and mulch the disturbed area immediately after construction.
6. Heavy equipment and traffic should not be allowed on the level spreader, as they can cause
compaction of soil and disturbance of the slope grade.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. The spreader
should be regraded if ponding or erosion channels develop. Dense vegetation should be sustained and
damaged areas reseeded when necessary.
Removal
Level spreaders may be left in place or removed upon final site reclamation.
References
City of Knoxville, Stormwater Engineering, Knoxville BMP Manual - Best Management Practices. July 2003.
http://www.ci.knoxville.tn.us/engineering
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://www.dec.state.ny.us/website/dow/toolbox/escstandards>
United States Army Corps of Engineers (USACE), Engineering and Design - Handbook for the Preparation of
Storm Water Pollution Prevention Plans for Construction Activities. February 1997.
http://www.usace.army.mil/inet/usace-docs/eng-pamphlets/ep1110-1-16/
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LS -2
June 2008
TranSilann Fnr.tion
See nate 2
Figure LS -1
Level Spreader Installation
• 444
- k r y.
i * L d
k fa k -i A 44.
▪ * i i * *
Level trig for SpreacPer
See. r4:4e 1
Notes:
V'egc4hlyd tip for level
51:4ra1or moult' not too
€mslructed irom tie material.
Oo rut ailow any IrarriG oulo
✓ egetaled lip.
2 The lavl 26, of appo.ach
charnel stbull be a transeion
• arid h9arear tideless
than 1%.
d # * *
�* * *
Vegetated Lip
Transitmon miction
See rate 2
41,
**
6'- anin,
*
i4
4 i1*el -
f
Connie aggregate
gaboar zed wire -•;
baskeLcrtiahfon:
robars alreguLar
inlervels lu
anchor rigid lip ,' t *
• 49
4
▪ 4,4
• .F 4
* 4
* 4
* 4
J
▪ * 1 -
k i t
• 4 a •ti
JULe .1 L or excelsior nlat
so!piloil in plar..o nrxt
anchored 6- into gourd
1{i' 10 30- !ENV!
!
i
1r" rei▪ t
*Y` i '1i4
*
6' min.
4
Sre wire Basket
acuJ *. • 4
or cotillion 10 Qrut. m1 i * 4,6 `
web stakes 4 i i 4.4
4 4.
I it
Rigid Lip
NOT TO SCALE
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2' 11iS i
LS -3
G,eo1exfle illter Cc4ee31
June 2008
Roadside Ditches (RSD) and Turnouts (TO)
Description
Roadside ditches are channels constructed parallel to roads. The ditches convey concentrated runoff of
surface water from roads and surrounding areas to a stabilized outlet. Turnouts (wing ditches) are extensions
of roadside ditches. Turnouts effectively remove runoff water from the roadside ditch into well -stabilized areas
before it reaches a waterway.
Applicability
• Roadside ditches should be used for all roads built on sloping topography and with either an insloped
or a crowned design.
• Ditch turnouts should be used as much as possible but their best use may be on slopes longer than
150 ft or greater than 5%, as conditions allow.
• Turnouts are applicable where fairly flat naturally vegetated areas exist at intervals by the roadside.
Limitations
• If these structures are not installed correctly they may become a source of erosion.
• Roadside ditches do not necessarily filter sediment from runoff.
• Turnouts should be on gradual slopes only.
• Turnouts require vegetative cover or other filter at the discharge point.
• Turnouts only work well if small volumes of runoff drain into the turnout. Turnouts should only receive
runoff from the road and ditch surface, not from large, uphill watersheds.
Design criteria
No formal design is required.
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RSD/TO-1
June 2008
Construction specifications
Roadside ditches
1. Roadside ditches should be constructed with no projections of roots, stumps, rocks, or similar debris.
2. Excavate ditches along roadside to a width and depth that can handle expected flows according to
Figure RSD -1.
3. All ditches shall have uninterrupted positive grade to an outlet. Slope ditch so that water velocities do
not cause excessive erosion, but no less than 0.5%. If steep slopes and high velocities exist, use
check dams to slow runoff and catch sediment.
4. To control erosion and collect sediment, construct aggregate check dams according to Figure CD -1 of
Check Dam (CD).
5. All ditches shall convey runoff to a sediment trapping device such as a Sediment Trap (ST) or an
undisturbed, well vegetated, and stabilized area at non-erosive velocity.
6. If necessary, stabilize ditches with Riprap (R) or erosion control blanketing.
Turnouts
1. Use turnouts wherever possible and on undisturbed soil.
2. Slope turnout gradually down from bottom of roadside ditch.
3. Angle turnout at approximately 30 degrees to the roadside ditch.
4. Discharge turnout into well -vegetated area or install a secondary control such as a wattle, sediment
trap, or silt fence. As a good Rule of Thumb, the vegetated outlet area should be a minimum of
one-half the size of the total drainage area draining into it. If well -vegetated outlet areas are not
available, use culverts or other controls to direct runoff to a stabilized area.
5. Space turnouts according to slope as indicated on Figure TO -1.
6. Turnouts only work well if small volumes of runoff drain into the turnout. Turnouts should only receive
runoff from the road and ditch surface, not from large, uphill watersheds.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Road ditches
and turnouts should be inspected for any signs of channelization, and repaired as necessary. Structures will
fail if water exits in channelized flow. Also inspect for sediment buildup at the outlet and at aggregate check
dams and remove if necessary.
References
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
United States Department of the Interior and United States Department of Agriculture. Surface Operating
Standards and Guidelines for Oil and Gas Exploration and Development "Gold Book". BLM/WO/ST-
06/021+3071. Bureau of Land Management (BLM). Denver, Colorado. Fourth Edition, 2006.
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM
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RSD/TO-2
June 2008
— Cur slope
Figure RSD -1
Roadside Ditch Installation
rpyp•1 Stooge Area
NOT TO SCALE
M7OT TO OGALE
mantra meal -X.2
(iv Yedelmet: ft•'I
3-5 Raalrwy
Stabdira with egg oga1n check, dams and
'iRinV c arosiun alun4eiing i1 nmsassseryr
NAP 51%4i6e110.5%ID20%laelabiixEKIoupe4
Figure TO -1
Turnout Layout
lt,P'J
R0146010 Dirii D.5% min_
RaactWa NM 0.7%nitn.
■ea: eednrerlt lrapY
M:\Encana\BMP Manual\BMP Manual - Round 2\SWMM
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(ex: wit 1E•V !
Oa: wads)
RSD/TO-3
Road Slope TLI1r t
M
e2?�4001 1t
1-5% 100 5.
5-10% 161111.
}1(15h i5L
June 2008
Run -On Diversion (ROD)
Definition
A run-on diversion is a drainage way of parabolic or trapezoidal cross section with a supporting ridge on the
lower side that is constructed across the slope. The purpose of a run-on diversion is to prevent off-site storm
runoff from entering a disturbed area and to direct the runoff to a sediment or erosion control device.
Applicability
A run-on diversion is typically a permanent control designed for a drainage area larger than 10 acres where
high flow is expected. Run-on diversions are used upslope of cut or fill slopes to convey or divert flows away
from disturbed areas.
Limitations
• The area around the diversion channel that is disturbed by its construction must be stabilized (with
vegetation or other erosion control) so that it is not subject to erosion similar to that of the steep slope
the diversion is built to protect.
• To alleviate erosion capability, diversions must be directed into a stabilized outlet or well -vegetated
area or to sediment trapping devices, where erosion sediment can settle out of the runoff before being
discharged to surface waters.
• Run-on diversions should be used with caution on soils subject to slippage.
Design criteria
Location
Run-on diversions should be located above cut or fill slopes. Where possible (shallow slopes), a vegetated
buffer strip should be left between the edge of the cut or fill slope and the diversion. Location shall also
depend on outlet conditions, topography, land use, soil type, length of slope, and the development layout.
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ROD -1
June 2008
Capacity
Peak rates of runoff values used in determining the capacity requirements shall be as outlined by TR -55,
Urban Hydrology for Small Watersheds. The constructed diversion shall have capacity to carry, as a
minimum, the peak discharge from a 10 -year frequency rainfall event with freeboard of not less than 0.3 feet.
Cross section
See Figure ROD -1 for details. The diversion channel shall be parabolic or trapezoidal in shape. The diversion
shall be designed to have stable side slopes. The side slopes shall not be steeper than 2:1 and shall be flat
enough to ensure ease of maintenance of the diversion and its protective vegetative cover. The ridge shall
have a minimum width of 4 feet at the design water elevation; a minimum of 0.3 feet freeboard and a
reasonable settlement factor (10%) shall be provided.
Velocity and grade
The permissible velocity for the specific soil type will determine the maximum grade. The maximum
permissible velocity for sand and silt vegetated channels is 3 ft/sec, and 5 ft/sec for clay vegetated channels.
Run-on diversions are not usually applicable below high sediment producing areas unless structural
measures, designed to prevent damaging accumulations of sediment in the channels, are installed with, or
before, the diversions.
Construction specifications
1. All trees, brush, stumps, obstructions, and other objectionable material shall be removed and
disposed of so as not to interfere with the proper functioning of the diversion
2. All diversions shall have uninterrupted positive grade to an outlet.
3. Each diversion must have an adequate outlet where outflow will not cause damage. Diverted
runoff shall outlet to a sediment trapping device or into an undisturbed stabilized area at non-
erosive velocities. Vegetated outlets shall be installed before diversion construction, if needed, to
ensure establishment of vegetative cover in the outlet channel.
4. The diversion shall be excavated or shaped to line, grade, and cross section as required to meet
the criteria specified herein, and be free of bank projections or other irregularities which will
impede normal flow.
5. Parabolic and triangular-shaped, grass -lined channels should not have a top width of more than
30 feet. Trapezoidal, grass -lined channels may not have a bottom width of more than 15 feet
unless there are multiple or divided waterways, they have a riprap center, or other methods of
controlling the meandering of low flows are provided.
6. If grass -lined channels have a base flow, a stone center or subsurface drain or another method for
managing the base flow must be provided.
7. Fills shall be compacted as needed to prevent unequal settlement that would cause damage in
the complete diversion.
8. All earth removed and not needed in construction shall be spread or disposed of on the well pad
side of the diversion so that it will not interfere with the functioning of the diversion.
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ROD -2
June 2008
9. Immediately after the ridge and channel are constructed, they must be seeded or hydroseeded,
and mulched or covered with erosion blanketing according to Revegetation (RV), Mulching (M),
and/or Erosion Control Blanket (ECB) along with any disturbed areas that drain into the diversion.
a. For design velocities less than 3.5 ft/sec, seeding and mulching may be used for
establishment of the vegetation. It is recommended that, when conditions permit,
temporary diversions or other means should be used to prevent water from entering the
diversion during the establishment of the vegetation.
b. For design velocities or more than 3.5 ft/sec, the diversion shall be stabilized with seeding
protected by Jute or Excelsior matting, or with seeding and mulching including temporary
diversion of the water until the vegetation is established.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Channels
should be cleared of sediment, repairs made when necessary, and seeded areas reseeded if a vegetative
cover is not established. Maintain diversion capacity, ridge height, and outlet elevations especially if high
sediment yielding areas are in the drainage area above the diversion. Establish necessary cleanout
requirements. Redistribute sediment as necessary to maintain the capacity of the diversion.
Removal
Run-on diversions shall remain in place until final reclamation.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://wvvw.dec.state.ny.us/website/dow/toolbox/escstandards>
United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), Field
Office Technical Guide. 2002. <www.nrcs.usda.gov/technical/efotg>
F OVY
Design Top Width
Figure ROD -1
Run -On Diversion Installation
Ma,. 1
43' Rn 1 -
1v' Se'.Ilrsren1
Sh01511We wi1Mi' ow fmfl
and SArOdr or Erosion
Contra elarlsal
15' 111x...
HOT TO $CJ&E
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ROD -3
Srna 1 L), re nson Ir_i
Capuru 'turwll fruiu
8urrn at D ycrsi:xi
June 2008
Slope Drain (SD)
Description
A slope drain is a conduit extending the length of a disturbed slope and serving as a temporary outlet for a
diversion. Slope drains convey runoff without causing erosion on or at the bottom of the slope. This practice
is a temporary measure used during grading operations until permanent drainage structures are installed and
until slopes are permanently stabilized. They are typically used for less than 2 years.
Applicability
Slope drains can be used on most disturbed slopes to eliminate gully erosion problems resulting from
concentrated flows discharged at a diversion outlet. Recently graded slopes that do not have permanent
drainage measures installed should have a slope drain and a temporary diversion installed. A slope drain
used in conjunction with a diversion conveys stormwater flows and reduces erosion until permanent drainage
structures are installed.
Limitations
The area drained by a temporary slope drain should not exceed 5 acres. Physical obstructions substantially
reduce the effectiveness of the drain. Other concerns are failures from overtopping because of inadequate
pipe inlet capacity, and reduced diversion channel capacity and ridge height.
Design criteria
No formal design is required.
Construction specifications
See Figure SD -1 for installation details.
1. The slope drain shall have a slope of 3 percent or steeper.
2. The top of the diversion berm over the inlet pipe, and those diversions carrying water to the pipe,
shall be at least 6 inches higher at all points than the top of the inlet pipe.
3. A flared end section of corrugated metal shall be attached to the inlet end of the pipe with a
watertight connection. The corrugated metal pipe should have watertight joints at the ends.
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SD -1
June 2008
4. The drain should consist of heavy-duty material manufactured for the purpose and have
grommets for anchoring at a spacing of 10 feet or less. The pipe is typically corrugated plastic or
flexible tubing, although for flatter, shorter slopes, a polyethylene -lined channel is sometimes
used. Where flexible tubing is used, it shall be the same diameter as the inlet pipe and shall be
constructed of a durable material.
5. The soil around and under the pipe and end section shall be hand tamped in 4 in. lifts to the top of
the diversion berm.
6. The slope drain shall outlet into a sediment trapping device when the drainage area is disturbed.
A riprap apron shall be installed below the pipe outlet where water is being discharged into a
stabilized area.
7. A riprap apron shall be used below the pipe outlet where clean water is being discharged into a
stabilized area.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspections
should determine if capacity or slope drain was exceeded or if blockages occurred. Repairs should be made
promptly. Construction equipment and vehicular traffic must be rerouted around slope drains.
Removal
Remove slope drain on completion of construction and stabilization activities.
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://wvvw.dec.state.ny.us/website/dow/toolbox/escstandards>
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SD -2
June 2008
Anchnr 9r? fill SIS
Provide outlet
prolecU4n
Flarud i rx1
SEt14rl
Figure SD -1
Slope Drain Installation
EarMorn Rem cx divnrwn {compacted)
Corri ate l melel exle'r on caller
Vika inn L_RJF
Rigid or flexable ppEr
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10' Mel
D
SD -3
45P$II rgmpacgpd �I;bl4
P&1 slope
Flared Efal
seclir>'n
Pr$inogn Prp Toting
Area Diarrralar (in.)
leges) D
c0.5 12
<1.5 18
{2.5 21
c3.5 24
‹5 a0
June 2008
Trench Breakers (TB)
Description
Trench breakers, also known as trench plugs, are used to slow the flow of subsurface water along a pipeline
trench. Trench breakers may be constructed of materials such as sand bags or polyurethane foam.
Applicability
Trench breakers may be used in the following applications:
• On steep slopes.
• Above wetlands.
• At waterbody crossings.
• At road crossings.
Design criteria
No formal design is required.
Construction specifications
1. Trench breakers should be installed both before and after the lowering -in of pipeline.
2. An engineer or similarly qualified professional shall determine the need for and spacing of trench
breakers. Otherwise, spacing shall be according to the following table:
Slope (%)
Spacing (feet)
5 —15
300
15-30
200
>30
100
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June 2008
3. At a minimum, install a trench breaker at the base of slopes greater than 5 percent where the
base of the slope is less than 50 feet from a waterbody or wetland and where needed to avoid
draining a waterbody or wetland.
4. Trench breakers should be installed to the top of the excavated trench line.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Repair any
damaged areas.
References
Federal Energy Regulatory Commission (FERC), Upland Erosion Control, Revegetation, and Maintenance
Plan. January 2003.
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TB -2
June 2008
Water Bar (WB)
Description
A water bar is an earthen ridge, or ridge and channel, constructed diagonally across a sloping road, trail, or
disturbed area that is subject to erosion. Water bars are normally used for drainage and erosion protection of
buried pipelines or closed, blocked, or infrequently used roads to limit the accumulation of erosive volumes of
water by diverting surface runoff at pre -designed intervals.
Applicability
Water bars are applicable where runoff protection is needed to prevent erosion on sloping access right-of-
ways or long, narrow sloping areas generally less than 100 feet in width. This is a practice that is often used
on buried pipelines, limited -use roads, trails, and firebreaks. It is an excellent method of retiring roads and
trails as well as abandoned roads where surface water runoff may cause erosion of exposed mineral soil.
Limitations
• Not for use on concentrated flows
• May cause concentrated flows from sheet flow
• Requires vegetative cover or other filter at discharge point
Design criteria
No formal design is required.
Construction specifications
See Figure WB -1.
1. Clear the base for the ridge before placing fill.
2. Install the water bar across the right-of-way according to Figure WB -1 as soon as the base is
cleared and graded. The off -slope drainage should be 2 to 5 percent.
3. Use a trackhoe or bulldozer to compact the ridge to the design cross section.
4. Vehicle crossings shall be stabilized with gravel. Exposed areas shall be immediately seeded and
mulched.
5. Extend the water bar inlet and outlet 1 foot or more beyond the edge of the right-of-way or
disturbed area to keep the diverted water from re-entering the area.
6. Space the water bars according to Table WB -1.
7. Locate the outlet on an undisturbed area. Field spacing shall be adjusted to use the most stable
outlet areas. Outlet protection will be provided when natural areas are not adequate.
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WB -1
June 2008
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspect water
bars for erosion damage and sediment. Check outlet areas and make repairs as needed to restore operation.
Removal
If water bars are used on a closed or blocked road, they should be removed prior to re -opening of the road.
Water bars on infrequently used roads or other disturbed areas may remain in place as long as necessary.
References
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
Maine Department of Conservation, Best Management Practices for Forestry: Protecting Maine's Water
Quality. Maine Forest Service, Forest Policy and Management Division. Augusta, Maine. 2004.
<http://www.state.me.us/doc/mfs/pubs/pdf/bmp_manual/bmp_manual.pdf>
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://wwvv.dec.state.ny.us/website/dow/toolbox/escstandards>
Table WB -1
Water Bar Spacing
Road/Trail Grade (%)
Low to Non -Erosive Soils (1)
Erosive Soils (2)
0 - 5
245'
130'
6 — 10
200'
100'
11 - 15
150'
65'
16 - 20
115'
50'
21 - 30
100'
40'
31+
50'
30'
'Low Erosion Soils = Coarse Rocky Soils, Gravel, and Some Clay
2High Erosion Soils = Fine, Friable Soils, Silt, Fine Sands
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WB -2
June 2008
Figure WB -1
Water Bar Installation
EDGE OF R.OW.
OUTLET WO
STABILIZED AREA
(WELL VEGETATED)
NOT TO SCALE
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WB -3
EDGE OF R.O.W.
Nola. Side 5Ic7pel shall be 4:1 where
vehicles cross and wa r bar
shall bestabtlrsEwith grarel.
June 2008
Sediment Control BMPs
Check Dam (CD)
Detention Pond (DP)
Filter Berm (FB)
Sediment Reservoir (SedR)
Sediment Trap (ST)
Silt Fence (SF)
Slash (SL)
Stabilized Construction Entrance (SCE)
Straw Bale Barrier (SBB)
Wattles (W) (BMP is provided with erosion controls)
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June 2008
Check Dam (CD)
Description
Check dams are small, temporary dams constructed across a diversion or roadside ditch. Check dams can be
constructed using aggregate, rock, sandbags, gravel bags, earth with erosion control blanketing, straw bales,
or wattles and are used to slow the velocity of concentrated flow in a channel and thus reduce erosion. As a
secondary function, check dams can also be used to catch sediment from the channel itself or from the
contributing drainage area as stormwater runoff flows through or over the structure.
Applicability
• Check dams are most often used in small, open channels with a contributing drainage area of less
than 10 acres, and side slopes of 2:1 or less. Check dams may be used in the following applications:
• In diversions or roadside ditches where it is not practical to line the channel or implement other flow
control and sediment control practices.
• In diversions or roadside ditches where temporary seeding has been recently implemented but has
not had time to take root and fully develop.
• As a series of check dams, spaced at appropriate intervals, used in one of the above two applications.
Limitations
• Check dams should not be used in live, continuously flowing streams unless approved by an
appropriate regulatory agency.
• Check dams may require frequent removal of accumulated sediments. Dams should therefore be
located in areas accessible to maintenance vehicles.
• Leaves have been shown to be a significant problem by clogging check dams in the fall. Therefore,
they might necessitate increased inspection and maintenance.
• Straw bale check dams decompose over time, and may be consumed by livestock.
Design criteria
No formal design is required.
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CD -1
June 2008
Construction specifications
1. Install aggregate check dams according to Figure CD -1. Other types of check dams shall have similar
designs.
2. Check dams should be located in areas accessible to maintenance vehicles for the periodic removal
of accumulated sediments.
3. Dams should be installed with careful placement of the construction material. Mere dumping of the
dam material into a channel is not appropriate and will reduce overall effectiveness.
4. Check dams can be constructed from a number of different materials. When using rock, the material
diameter should be 1 to 15 inches depending on the expected velocity and quantity of runoff within the
channel. Aggregate check dams, ideal for application within roadside ditches, should use a material
diameter between 3/4 to 1-1/2". Earth collected during excavation of diversions or roadside ditches
may also be placed as check dams if covered with erosion control blanketing. Straw bales, wattles, or
sand/gravel bags may also be used, but only if rock or aggregate is unavailable or not feasible for the
location.
5. All check dams should have a maximum height of 3 feet with sufficient space up slope from the barrier
to allow ponding, and to provide room for sediment storage. The center of the dam should be at least
6 inches lower than the edges. This design creates a weir effect that helps to channel flows away
from the banks and prevent further erosion.
6. Additional stability can be achieved by implanting the dam material approximately 6 inches into the
sides and bottom of the channel.
7. In order to be most effective, dams used in a series should be spaced such that the base of the
upstream dam is at the same elevation as the top of the next downstream dam.
8. When installing more than one check dam in a channel, outlet erosion stabilization measures should
be installed below the final dam in the series. Because this area is likely to be vulnerable to further
erosion, riprap, erosion control blanket lining, or some other stabilization measure is highly
recommended.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. During
inspection, large debris, trash, and leaves should be removed. The center of a check dam should always be
lower than its edges. If erosion or heavy flows cause the edges of a dam to fall to a height equal to or below
the height of the center, and the effectiveness of the BMP is compromised, repairs should be made
immediately. Accumulated sediment should be removed from the upstream side of a check dam when the
sediment has reached a height of approximately one-half the original height of the dam (measured at the
center). Close attention should be paid to the repair of damaged or rotting straw bales, end runs, and
undercutting beneath bales. Replacement of bales should be accomplished promptly.
Removal
Removal of check dams is optional. Check dams within roadside ditches are usually used as temporary
controls, where other check dams may be left in place to silt out. If removing a check dam, all accumulated
sediment should be removed. Removal of a check dam should be completed only after the contributing
drainage area has been completely stabilized. Permanent vegetation should replace areas from which gravel,
stone, logs, or other material has been removed.
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CD -2
June 2008
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
<http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
r,ker sway
SECTION VIEW
6oklom a1 Swale
Figure CD -1
Aggregate Check Dam Installation
Trenah6' Ino641.Ye
PROFILE VIEW
Tap arsketa
Flow Geo9ekt a (eaa8t' tot be
coat ar check clam'
@attain ar Seale
E IrUP�
Giro taxi ilm 1"
TaF ar-4e
Bal NAT of 5.4me
NOT TO,SOALE
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AgErnall3 L3 d. •1'r`�
L — -
CD -3
Lvpliancy.wChtlwilPr,r +.:.a-ri1)
are equal *Minoan
I~ali D
June 2008
Detention Pond (DP)
Description
A detention pond shall be constructed on each well pad to collect and store all runoff from the surface of the
pad. A culvert with a locking gate may be installed to allow dewatering to occur if the water tests clean and is
acceptable for release from the pad.
Applicability
Detention ponds are applicable to all well pads.
Limitations
Well pads that have not been properly designed may collect runoff from areas other than the surface of the
pad, which may be more volume than the detention pond is designed to handle.
Design criteria
Detention ponds shall be sized for a 25 -year frequency storm. In general, 4,000 cubic feet (150 cubic yards) of
dry storage volume should be provided for each acre of pad surface area.
Construction specifications
Construct detention pond according to Figure DP -1.
Location
Detention ponds shall be located at an outside edge of the pad and as far as possible from the pad access
road, utilities, and all infrastructures.
Dewatering
Dewatering may be achieved through a 6- to 12 -inch corrugated metal culvert. The culvert invert shall be
located approximately 1 foot above the bottom of the pond to allow space for sedimentation. The culvert shall
be sloped and routed through the berm at the perimeter of the well pad to discharge down the fill slope and
directly into a pad perimeter diversion. A steel slide gate as manufactured by Waterman Industries, or similar,
may be installed at the culvert inlet. The gate may use a positive one-quarter turn cam lock which will hold the
gate in any position to enables easy regulation of flow.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspections
shall verify that the pond has not been disturbed and that the original storage capacity has been maintained. If
sedimentation has accumulated to within 2 inches of the culvert inlet, the sediment shall be removed while
avoiding any unnecessary disturbance to the pond.
Removal
The detention pond and culvert shall be removed upon completion of well pad activities and final stabilization.
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DP -1
June 2008
Figure DP -1
Detention Pond Installation
Shde
{Madel C.8 by Wetemren
f 1I1e* 9r WOW
Par! Penrnahr &arm
fr-12-Corrugated
Mgtal {:zll,urrl
Alyap twar
Feu
Perrlreler Cliyartion
r,cyrr
SCAC
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1' Wei Slrxage
D P-2
JrlpPror. 150 Cr try sloraga
poi' acre pr Oad aurieie area
Slmpa
1% Inn.
1 r �
Ply Slvraga 1
2 Max.
June 2008
Filter Berm (FB)
Description
A filter berm is a temporary ridge made up of natural materials that already occur on the project site such.
Brush filter berms use small tree branches, root mats, grass, leaves, stone, or other debris or material naturally
available or left over from site clearing and grubbing (slash). Rock filter berms use site gravel, stone, or rock.
Both types of filter berms are placed along a level contour to slow, filter, and divert flow and act as an efficient
form of sediment control. In some configurations, filter berms are covered with a filter cloth to stabilize the
structure and improve barrier efficiency.
Applicability
The drainage area for filter berms must be no greater than 2 acres. In addition, the drainage slope leading
down to a filter berm must be no greater than 2:1 and no longer than 100 feet. The following are suitable
applications:
• 5 to 7 feet beyond the toe of slopes.
• Along the site perimeter.
• Along streams and channels, or adjacent to roadways.
• Around temporary spoil areas or other small cleared areas.
Limitations
• Intended to be used only in gently sloping areas, and are not appropriate for high -velocity flow areas.
• Brush filter berms have limited usefulness because they are constructed of materials that decompose.
• A large amount of material is needed to construct a useful filter berm. Therefore, filter berms are only
applicable to sites where there is enough brush material from clearing and grubbing or rock material to
form a sufficiently sized berm.
• May be difficult to remove after construction.
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FB -1
June 2008
Design criteria
No formal design is required.
Construction specifications
Brush (slash) filter berms
See Figure FB -1 for installation details.
1. Place material cleared from the site across the slope or swale. Material with a diameter larger
than 6 inches should not be used.
2. Cut up brush if necessary and compact to avoid large voids within the barrier.
3. The barrier mound should be at least 3 feet high and 5 feet wide at its base.
4. It is recommended, but not required, that the mound be covered with a filter fabric barrier to hold
the material in place and increase sediment barrier efficiency. If using a filter fabric cover, bury
the edge in a trench 4 inches deep and 6 inches wide on the drainage side of the barrier. This is
done to secure the fabric and create a barrier to sediment while allowing stormwater to pass
through the water -permeable filter fabric. The fabric should be extended just over the peak of the
brush mound and secured on the down-slope edge of the fabric by fastening it to twine or small -
diameter rope that is staked securely.
Rock filter berms
See Figure FB -2 for installation details.
1. Place filter berm along a level contour. Use well -graded, angular site gravel or crushed rock of
medium to large diameter with larger rocks on the bottom.
2. If desired, cover with geotextile fabric or wire screen (especially if concentrated flows are
expected) to help keep berm in tack. Anchor fabric or wire by placing under the berm or use
stakes.
3. Trenching is not required.
4. Berms should be spaced according to the steepness of the slope, with berms spaced closer
together as the slope increases.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. If channels
form through void spaces in the barrier, the barrier should be reconstructed to eliminate the channels. Ensure
that sediment has not built up and that no damage has been done by vehicles. Regular inspection should
indicate the frequency of sediment removal needed. Accumulated sediment should be removed from the
uphill side of the barrier when sediment height reaches between 1/3 and 1/2 the height of the barrier.
Sediment should be disposed of and the filter material and/or fabric should be replaced if necessary. It is
important that repairs be performed at the first sign of deterioration to ensure that the berm is functioning
properly.
Removal
Remove filter berms after uphill drainage areas are stabilized. Rock and brush may be left in place only if it
does not cause any landscaping problems. Remove all manmade materials (wire, fabric, and/or stakes).
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June 2008
References
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Figure FB -1
Brush Filter Berm Installation
FIc
Gec4exlile GN wife
n ItrlgIDononalI
3' thyp. 'Misr!!
Exoawaloa SIsr
irsnoh and inaeil
fabric along bottom
(stal+.f3 labile
as needed!.
NOT TO SCALE
Cern{iaoled brash%.
tree lirnbs, rood rut,
grass. leaves. eic_
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5'.7° burrs
Ilse sof slope
FB -3
Slakes al 3'
spacing (hP.)
Rcpo, string, wire or (Mina
{weave back and rain
across Ixerril
June 2008
beyond
1op or limp4
Llai C"tarc ar Cru hrxt Ronk
NOT TO SCALE
Figure FB -2
Rock Filter Berm Installation
N66ir. Exliend end or b6mn upulope Il
aaold riyor around ends.
Wrap with geolextzm Apr wire mesh
currrunlr lorl lloevs aro CUpoct®d
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FB -4
Hole. Prate hemi eiony level vvukvr.
June 2008
Sediment Reservoir (SedR)
Description
Sediment reservoirs are large ponding areas that allow sediment to settle out of runoff water. They are often
installed at the base of well pads or down-slope of other large disturbed areas. Sediment reservoirs are
formed by excavating below grade and/or by constructing an earthen embankment with a level spreader type
of spillway to slow the release of runoff.
Applicability
Sediment reservoirs are applicable to any location where it is desired to capture runoff from a large drainage
area (up to 10 acres). Sediment reservoirs are also used as tertiary spill containment to prevent any
accidental discharges from leaving the site.
Limitations
• Regular maintenance is needed to remove sediment. Reservoirs should be located near roads or
where accessible to remove sediment.
• Water may remain in the reservoir for extended periods causing an ideal spot for mosquitoes and
other insects to gather. Locate the reservoir in a sunny spot if possible.
• Never construct a sediment reservoir on a live flowing stream or in wetlands.
Design criteria
Location
Reservoirs should be located at points of discharge from disturbed areas. The location will be determined by
the natural terrain, drainage pattern of the runoff, and the accessibility for maintenance. Sediment reservoirs
should not be located in areas where their failure due to stormwater runoff excess can lead to further erosive
damage of the landscape. Alternative diversion pathways should be designed to accommodate these
potential overflows. Sediment reservoir locations should also allow for easy maintenance access for the
periodic removal of accumulated sediment.
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SedR-1
June 2008
Storage capacity
A sediment reservoir should be designed to maximize surface area for infiltration and sediment settling. This
will increase the effectiveness of the reservoir and decrease the likelihood of backup during and after periods
of high runoff intensity. The approximate storage capacity of each trap should be 3,600 ft3 per acre of
contributing drainage area. The volume of a natural sedimentation reservoir can be approximated by the
following equation:
Volume (ft3) = 0.4 x surface area (ft2) x maximum pool depth (ft)
If the volume is more than 100 acre-feet the sediment reservoir should be constructed as designed by a
Professional Engineer.
Embankment
If the embankment is more than 10 feet high (measured vertically from the ground surface to the crest of the
spillway) the sediment reservoir should be constructed as designed by a Professional Engineer.
Construction specifications
1. If possible, sediment reservoirs, along with other perimeter controls, shall be installed before any land
disturbance takes place in the drainage area.
2. Reservoirs should be located above the floodplain, where possible.
3. Area under embankment shall be cleared, grubbed, and stripped of any vegetation and root mat. The
pool area shall be cleared.
4. The fill material for the embankment shall be free of roots and other woody vegetation as well as over-
sized stones, rocks, organic material or other objectionable material. The embankment shall be
compacted by traversing with equipment while it is being constructed. Seeding of the embankment
should be performed as soon as possible after construction of the sediment reservoir. Erosion control
blanketing may also be used to cover the embankment in combination with seeding or during time
periods when seeding is ineffective.
5. The spillway shall typically consist of a level spreader which may extend around as much as half of the
reservoir berm. The level spreader may consist of compacted earth, which will be vegetated on
completion of construction. However, if erosion is noted during inspections it may be necessary to
install aggregate, erosion control blanketing, straw bales, or wattles along the length of the level
spreader (see applicable BMP).
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. The primary
maintenance consideration for sediment reservoirs is the removal of accumulated sediment from the basin to
ensure the continued effectiveness of the reservoir. Sediments should be removed when the basin reaches
approximately 50 percent sediment capacity. Inspectors should also ensure that the reservoir is draining
properly and check the structure, specifically the level spreader, for damage from erosion.
Removal
After the contributing area has been properly stabilized, the reservoir may remain in place if the reservoir itself
is also fully stabilized, or the reservoir may be removed and the newly disturbed area shall be stabilized.
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June 2008
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
<http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
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June 2008
Sediment Trap (ST)
Description
Sediment traps are small to medium sized ponding areas that allow sediment to settle out of runoff water.
They are usually installed in a drainage way or other point of discharge from a disturbed area. Sediment traps
are formed by excavating below grade and/or by constructing an earthen embankment with a lined spillway to
slow the release of runoff.
Applicability
Sediment traps are generally temporary control measures used at the outlets of stormwater diversion
structures, channels, slope drains, construction site entrance wash racks, or any other runoff conveyance that
discharges waters containing erosion sediment and debris. Sediment traps should be used for drainage areas
less than 5 acres. The effective life span of these temporary structures is usually limited to 24 months. Traps
may be located in series to allow for backup control in case one trap fails.
Limitations
• Regular maintenance is needed to remove sediment. Traps should be located near roads or where
accessible to remove sediment.
• Although sediment traps allow for settling of eroded soils, because of their short detention periods for
stormwater they typically do not remove fine particles such as silts and clays.
• Water may remain in trap for extended periods causing an ideal spot for mosquitoes and other insects
to gather. Locate the trap in a sunny spot if possible.
• Never construct a sediment trap on a live flowing stream or in wetlands.
Design criteria
Location
Traps should be located at points of discharge from disturbed areas. The location will be determined by the
natural terrain, drainage pattern of the runoff, and the accessibility for maintenance. Sediment traps should
not be located in areas where their failure due to stormwater runoff excess can lead to further erosive damage
of the landscape. Alternative diversion pathways should be designed to accommodate these potential
overflows. Sediment trap locations should also allow for easy maintenance access for the periodic removal of
accumulated sediment.
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ST -1
June 2008
Storage capacity
A sediment trap should be designed to maximize surface area for infiltration and sediment settling. This will
increase the effectiveness of the trap and decrease the likelihood of backup during and after periods of high
runoff intensity. The approximate storage capacity of each trap should be 3,600 ft3 per acre of contributing
drainage area. Half of this volume may be in the form of wet storage (a permanent pool) and the other half
may be in the form of dry storage. When possible, the wet storage volume should be contained within the
excavated portion of the trap. The volume of a natural sedimentation trap can be approximated by the
following equation:
Volume (ft3) = 0.4 x surface area (ft2) x maximum pool depth (ft)
Construction specifications
See Figure ST -1 for installation details.
1. If possible, sediment traps, along with other perimeter controls, shall be installed before any land
disturbance takes place in the drainage area.
2. Traps should be located above the floodplain, where possible. If there are space constraints, several
small sediment traps may be constructed in series.
3. Area under embankment shall be cleared, grubbed, and stripped of any vegetation and root mat. The
pool area shall be cleared.
4. The fill material for the embankment shall be free of roots and other woody vegetation as well as over-
sized stones, rocks, organic material or other objectionable material. The embankment shall be
compacted by traversing with equipment while it is being constructed. Seeding of the embankment
should be performed as soon as possible after construction of the sediment trap. Erosion control
blanketing may also be used to cover the embankment in combination with seeding or during time
periods when seeding is ineffective.
5. The spillway may consist of a stone section in the embankment formed by a combination coarse
aggregate/riprap to provide for filtering/detention capability. Riprap shall be 4- to 8 -inch rock, while the
coarse aggregate shall be 1/2 to 3/4 inches. A geotextile may be placed at the stone -soil interface to
act as a separator.
6. Another option for the spillway is to use straw bales or wattles at the overflow point in the trap and line
the rest of the spillway with an erosion control blanket (see applicable BMP).
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. The primary
maintenance consideration for temporary sediment traps is the removal of accumulated sediment from the
basin to ensure the continued effectiveness of the sediment trap. Sediments should be removed when the
basin reaches approximately 50 percent sediment capacity. Inspectors should also ensure that the trap is
draining properly and check the structure for damage from erosion. The depth of the spillway should be
checked and maintained at a minimum of 1.5 feet below the low point of the trap embankment.
Removal
The structure shall be removed and the area stabilized when the drainage area has been properly stabilized.
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June 2008
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
<http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
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ST -3
June 2008
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I _ I
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cSk
June 2008
Silt Fence (SF)
Description
Silt fences are used as temporary perimeter controls around sites where there will be soil disturbance due to
construction activities. They consist of a length of filter fabric stretched between anchoring posts spaced at
regular intervals along the site perimeter.
Applicability
Silt fences are generally applicable to construction sites with relatively small drainage areas. They are
appropriate in areas where runoff will be occurring as low-level shallow flow, not exceeding 0.5 cubic feet per
second. The drainage area for silt fences generally should not exceed 0.25 acre per 100 -foot fence length.
Slope length above the fence should not exceed 100 feet. Silt fence may be used as temporary slope
breakers to reduce runoff velocity.
Limitations
• Silt fences should not be installed along areas where rocks or other hard surfaces will prevent uniform
anchoring of fence posts and entrenching of the filter fabric. This will greatly reduce the effectiveness
of silt fencing and can create runoff channels leading off site.
• Silt fences are not suitable for areas where large amounts of concentrated runoff are likely.
• Open areas where wind velocity is high may present a maintenance challenge, as high winds may
accelerate deterioration of the filter fabric.
• Silt fences should not be installed across streams, ditches, or waterways.
• When the pores of the fence fabric become clogged with sediment, pools of water are likely to form on
the uphill side of fence. Siting and design of the silt fence should account for this and care should be
taken to avoid unnecessary diversion of stormwater from these pools that might cause further erosion
damage.
Design criteria
The fence should be designed to withstand the runoff from a 10 -year peak storm event.
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SF -1
June 2008
Construction specifications
1. Erect silt fence according to Figure SF -1.
2. If standard strength fabric is used in combination with wire mesh, the support posts should be spaced
no more than 10 feet apart. If extra -strength fabric is used without wire mesh reinforcement, the
support posts should be spaced no more than 6 feet apart.
3. Stakes used to anchor the filter fabric should be either wooden or metal. Wooden stakes should be at
least 3 feet long and have a minimum diameter of 2 inches if a hardwood such as oak is used. Softer
woods such as pine should be at least 4 inches in diameter. When using metal post in place of
wooden stakes, they should have a minimum weight of 1.00 to 1.33 Ib/linear foot. If metal posts are
used, attachment points are needed for fastening the filter fabric using wire ties. The height of the
fence posts should be between 16 and 34 inches above the original ground surface.
4. Material for silt fences should be a pervious sheet of synthetic fabric such as polypropylene, nylon,
polyester, or polyethylene yarn, chosen based on minimum synthetic fabric requirements, as shown in
the following table:
Physical Property
Requirements
Filtering Efficiency
75 — 85% (minimum): highly dependent on local conditions
Tensile Strength at 20%
(maximum) Elongation
Standard Strength: 30 lbs/linear inch (minimum)
Extra Strength: 50 lbs/linear inch (minimum)
Ultraviolet Radiation
90% (minimum)
Slurry Flow Rate
0.3 gal/ft2/min (minimum)
5. Use a continuous roll of fabric to eliminate unwanted gaps in the fence. If a continuous roll of fabric is
not available, the fabric should overlap from both directions only at stakes or posts with a minimum
overlap of 6 inches.
6. Extend silt fence across grade and upslope for a short distance.
7. Compact backfill at base of fabric.
8. A trench should be excavated to bury the bottom of the fabric fence at least 6 inches below the ground
surface. This will help prevent gaps from forming near the ground surface that would render the
fencing useless as a sediment barrier.
9. If using silt fence as temporary slope breakers to reduce runoff velocity, space according to the
following table:
Slope (%)
Spacing (feet)
5 — 15
300
>15 — 30
200
>30
100
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspect silt
fences to ensure that they are intact and that there are no gaps at the fence -ground interface or tears along
the length of the fence. If gaps or tears which impact the effectiveness of the BMP are found, they should be
repaired or the fabric should be replaced immediately. Accumulated sediments should be removed from the
fence base when the sediment reaches one-third to one-half the height of the fence. Sediment removal should
occur more frequently if accumulated sediment is creating noticeable strain on the fabric and there is the
possibility of the fence failing from a sudden storm event.
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June 2008
Removal
Remove silt fences and all accumulated sediment after uphill drainage areas are stabilized by vegetation or
other means.
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
<http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
Keller, Gordon, and James Sherar, Low -Volume Roads Engineering, Best Management Practices Field Guide.
United States Department of Agriculture (USDA), Forest Service, US Agency of International
Development (USAID), 2005. <http://www.blm.gov/bmp/field%20guide.htm>
Figure SF -1
Silt Fence Installation
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June 2008
Slash (SL)
Description
Slash is any natural debris or material left over from site clearing and grubbing. Slash may include small tree
branches, root mats, grass, leaves, stone, etc... Placement of slash over disturbed areas can help control
off-site transport of sediment by slowing the flow of runoff, which minimizes erosion, and trapping sediment
until vegetation is established at the sediment source.
Applicability
Slash may be used for the following:
• To create a filter berm or windrow.
• As a blanket over any disturbed area, particularly pipeline corridors and areas of fill.
• As outlet protection for culverts.
Limitations
• Material may need to be cut up or broken into smaller pieces.
• Slash does not eliminate the need to revegetate.
• Slash is not applicable for steep slopes.
Design criteria
No formal design is required.
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June 2008
Construction specifications
1. For slash filter berms, see the Filter Berm (FB) BMP.
2. Prior to spreading slash over a disturbed area, the area should be seeded in accordance with the
Revegetation BMP.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspect for any
excessive erosion and replace slash with an alternate BMP if necessary (such as erosion control blanket).
Removal
Removal of slash is not necessary.
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June 2008
Stabilized Construction Entrance (SCE)
Description
A stabilized construction entrance (tracking pad) is a pad of gravel over filter cloth where construction traffic
leaves a site. The purpose of a stabilized entrance to a site is to minimize the amount of tracked mud and dust
that leaves a site. As a vehicle drives over the gravel pad, mud and sediment are removed from the vehicle's
wheels and off-site transport of soil is reduced. The gravel pad also reduces erosion and rutting on the soil
beneath the stabilization structure. The filter fabric separates the gravel from the soil below, preventing the
gravel from being ground into the soil. The fabric also reduces the amount of rutting caused by vehicle tires by
spreading the vehicle's weight over a larger soil area than just the tire width.
Applicability
Typically, stabilized construction entrances are installed at locations where construction traffic leaves or enters
an existing paved road. However, the applicability of site entrance stabilization should be extended to any
roadway or entrance where vehicles will access or leave the site.
Limitations
• Although stabilizing a construction entrance is a good way to help reduce the amount of sediment
leaving a site, some soil may still be deposited from vehicle tires onto paved surfaces. To further
reduce the chance of these sediments polluting stormwater runoff, sweeping of the paved area
adjacent to the stabilized site entrance is recommended.
• Sediment traps or other secondary sediment controls are needed to capture that sediment that
accumulates at the pad and may run off during storm events.
Design criteria
No formal design is required.
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June 2008
Construction specifications
See Figure SCE -1 for installation details.
1. Locate the pad approximately 60 feet back from the entrance at any county road.
2. If the pad is constructed on a crowned road, a roadside ditch with check dams or sediment traps
shall be located on both sides of the road to collect runoff from the pad. If the road slopes to only
one side of the road then only one roadside ditch with sediment controls will be needed.
3. Place woven or non -woven fabric filter cloth over the entire area prior to placing the stone. Piping
of surface water under entrance shall be provided as required.
4. Place a matrix of 1" and 2" stone gravel, or reclaimed or recycled concrete equivalent, to a
minimum thickness of six (6) inches, a minimum width of 12 feet and a minimum length of 50 feet.
5. All surface water flowing or diverted toward construction entrance shall be piped across the
entrance. If piping is impractical, a mountable berm with 5:1 slopes will be permitted.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Stabilization of
site entrances should be maintained until the remainder of the construction site has been fully stabilized.
Stone and gravel might need to be periodically added to each stabilized construction site entrance to keep the
entrance effective. Soil that is tracked off site should be swept up immediately for proper disposal.
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
<http://www.dot.state.co. us/environ mental/envWaterQual/wgms4.asp>
Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES).
Construction Site Storm Water Runoff Control. Washington, D.C., February, 2003.
<http://cfpub.epa.gov/npdes/stormwater/menuofbmps/con_site.cfm>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
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SCE -2
June 2008
Figure SCE -1
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Road Side Bitch NM
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1!L4
June 2008
Straw Bale Barrier (SBB)
Description
A straw bale barrier is a series of entrenched and staked straw bales placed on a level contour to intercept
sheet flows. The barrier reduces runoff velocity and filters sediment laden runoff from small drainage areas of
disturbed soil. The barrier may also be used to protect against erosion. Straw bale barriers have an estimated
design life of three (3) months.
Applicability
Straw bale barriers may be used below disturbed areas subject to sheet and rill erosion where the length of
slope above the straw bale barrier does not exceed the following limits:
Constructed Slope
Percent Slope
Slope Length (ft)
2:1
50%
25'
3:1
33%
50'
4:1
25%
75'
Straw bales may be used in the following applications:
• Below the toe of erodible slopes or other small cleared areas
• At the top of slopes to divert runoff away from disturbed slopes
• As sediment traps at outlets to culverts, ditches, turnouts, etc.
• Along the perimeter of a site
• Around temporary stockpiles and spoil areas
• Along streams and channels for both erosion and sediment control
• As check dams across mildly sloped swales or construction roads
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June 2008
Limitations
• For short-term use only
• For use below small drainage areas less than 2 acres
• Decomposes over time
• May be consumed by livestock
• Straw bales must be certified weed free to avoid invasive weeds that may develop and should not be
used in areas where weeds are a concern.
• Removal of anchor stakes will be necessary after stabilization is complete
• Not recommended for concentrated flow, live streams, or swales where there is the possibility of a
washout
Design criteria
No formal design is required.
Construction specifications
See Figure SBB-1 for installation details.
1. Bales shall be placed in a single row on a level contour with ends of adjacent bales tightly abutting
one another. Bales shall be certified weed free.
2. Allow sufficient space up slope from the barrier to allow ponding, and to provide room for sediment
storage.
3. All bales shall be either wire -bound or string -tied. Straw bales shall be installed so that bindings
are oriented around the sides rather than along the tops and bottoms of the bales in order to
prevent deterioration of the bindings.
4. A trench shall be excavated the width of a bale and the length of the proposed barrier to a
minimum depth of 4 inches. Stake the bales with minimum 2" x 2" x 36" wood stakes or standard
"T" or "U" steel posts (minimum weight of 1.33 pounds per linear foot).
5. After the bales are staked and chinked (gaps filled by wedging), the excavated soil shall be
backfilled against the barrier. Backfill soil shall conform to the ground level on the downhill side
and shall be built up to 4 inches against the uphill side of the barrier.
6. Each bale shall be securely anchored by at least two stakes driven through the bale. The first
stake or steel post in each bale shall be driven toward the previously laid bale to force the bales
together. Stakes or steel pickets shall be driven a minimum 12 inches deep into the ground to
securely anchor the bales.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Close attention
should be paid to the repair of damaged or rotting bales, end runs and undercutting beneath bales. Necessary
repairs to barriers or replacement of bales should be accomplished promptly. Sediment deposits should be
removed when the level of deposition reaches approximately one-half the height of the barrier.
Removal
Straw bale barriers may be removed when they have served their usefulness or may remain in place to
decompose over time. Straw bales should not be removed, however, until the upslope areas have been
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SBB-2
June 2008
permanently stabilized. Any sediment deposits remaining in place after the straw bale barrier is no longer
required should be dressed to conform to the existing grade, prepared and seeded.
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
<http://www.dot.state.co. us/environ mental/envWaterQual/wgms4.asp>
Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization
(RAPPS) of Oil and Gas Construction Sites. April 2004.
New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and
Sediment Control. New York. Fourth Edition, 1997.
<http://wvvw.dec.state.ny.us/website/dow/toolbox/escstandards>
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Figure SBB-1
Straw Bale Installation
SBB-3
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June 2008
Wattles (W)
Wattles BMP is provided in Erosion Control section above.
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W-1
June 2008
Non-Stormwater BMPs
Dewatering (DW)
Dust Control (DC)
Material Delivery and Storage (MDS)
Scheduling (S)
Spill Prevention and Control (SPC)
Vehicle and Equipment Maintenance (VEM)
Waste Management (WM)
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Dewatering (DW)
Description
Dewatering involves the removal and discharge of excess water from construction sites. Excess water may
be due to groundwater, accumulated precipitation after a storm event (stormwater), or water used during
construction activities (i.e. for the testing of pipelines). Proper removal of excess water helps to prevent
potential pollutants (such as sediment or toxic and petroleum products) from entering watercourses. Sediment
control from dewatering operations is required on all projects where excess water containing sediment or
other pollutants is planned to be discharged. A temporary settling or filtering device should be used to avoid
pollutant discharges from dewatering operations.
Applicability
These practices are implemented where groundwater, accumulated precipitation (stormwater), or other
water used during construction will be discharged from a site.
Limitations
• Site conditions will dictate design and use.
• A settling device often allows only minimal settling time for sediment particles.
• Multiple sediment control methods shall be used, if necessary, for better sediment removal when site
conditions allow.
• The controls discussed in this BMP address sediment only. If the presence of polluted water is
identified, dewatering pollution controls should be implemented in accordance with regulatory
requirements.
Standards
Groundwater dewatering
1. All dewatering operations must comply with the Stormwater Management Plan. Discharges to the
ground of water from construction dewatering activities may be authorized, provided that:
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June 2008
a. The source is groundwater and/or groundwater combined with stormwater that does not
contain pollutants in concentrations exceeding the State groundwater standards in
Regulations 5 CCR 1002-41 and 42
b. The source is identified
c. BMPs are utilized
d. These discharges do not leave the site as surface runoff or to surface waters
2. Dewatered groundwater shall be pumped or diverted to a sediment control BMP prior to discharge to
the ground.
Stormwater Dewatering
1. The discharge of pumped stormwater (not including groundwater or other non-stormwater sources)
from excavations, ponds, depressions, etc., to surface water, or to a municipal separate storm -sewer
system is allowed as long as the dewatering activity and associated BMPs are implemented in
accordance with this manual.
2. Stormwater that collects in open depressions or trenches during construction activities will be
dewatered into an existing sediment control, such as a detention pond, a sediment trap, or simply into
a well -vegetated area to percolate into the ground and catch suspended sediment.
Pipeline Dewatering
Once the hydrostatic testing of pipelines has been completed, dewatering of the pipeline will occur.
1. Insert a displacer, commonly referred to as a pig, in the pipeline.
2. Regulate the discharge rate and utilize energy dissipation devices and/or sediment controls as
necessary to prevent erosion, streambed scour, suspension of sediments, or excessive stream flow.
Specifications
One of several types of dewatering structures may be constructed depending on site conditions and type of
operation:
1. Water may be pumped or directed into existing stormwater sediment controls (such as sediment traps)
capable of handling the volume and flow rate of dewatered water.
2. Water may be pumped or directed into a temporary settling device as described below.
3. Water may be land applied to approved non -wetland vegetation areas and allowed to soak into the
soil.
4. Water may be hauled away from the project for disposal in accordance with applicable laws and
regulations.
If existing stormwater sediment controls are used to control water, the applicable sections of this BMP
Manual shall be followed.
If a settling device is utilized, the following design criteria shall be followed:
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DW -2
June 2008
Straw Bale/Silt Fence Pit
• It is recommended that the structure consist of an excavated basin surrounded by a perimeter control
such as wattles, hay bales, or silt fence (see Figure DW -1). Install wattles, hay bales, or a silt fence as
described in applicable sections of this BMP Manual.
• The following formula should be used to determine the storage volume of the sediment tank:
Pump discharge (gpm) x 16 = cubic feet of storage required
• The excavated area should be a minimum of 3 feet below the base of the perimeter control. The
excavated portion will serve for wet storage, and the remainder will provide dry storage.
• When water reaches the outlet crest, pumping must stop until the water drains down to the elevation
of the excavated area.
• The remaining water may be removed only after a minimum of 6 hours of sediment settling time. This
effluent should be pumped across an area with established vegetation or through a silt fence prior to
entering a watercourse.
• When the excavated area becomes filled to one-half of the excavated depth, accumulated sediment
should be removed and properly disposed of.
Sediment Filter Bag
• A filter bag, constructed of non -woven geotextile material (to provide adequate filtering ability to
capture the larger soil particles from the pumped water), will be clamped around the dewatering pump
discharge hose so that all of the pumped water passes through the bag.
• The filter bag should be used in combination with a straw bale/silt fence pit when located within 50 feet
of a stream. When the distance to a stream is greater than 50 feet, the bag may be placed on well -
vegetated area, or on an aggregate pad. The bag should never be placed on bare soil.
• The capacity of the bag should be adequate to handle the dewatering pump discharge, and should be
based on the bag manufacturer's recommendation.
• When used in conjunction with a straw bale/silt fence pit, a filter bag may be operated until the water in
the pit reaches the crest of the emergency overflow.
• When placed on either a stone pad or well -vegetated area, the bag may be operated until such time
the discharge from the bag reaches a stream.
• When the bag has been completely filled with sediment it should be cut open, sediment regraded in
place, and immediately stabilized with an erosion control.
A settling device and/or sediment control may not be needed if the water is discharged to a well stabilized,
on-site, vegetated area. The stabilized area should be capable of filtering sediment while at the same time
withstanding the velocity of the discharged water without eroding. A minimum filtering length of 75 feet is
recommended for the stabilized area.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. If using a
settling device, sediments should be removed once they have accumulated to one-half of the excavated
depth and properly disposed of. Sediment removal from dewatering devices shall be stabilized at the project
site at pre -designated locations or shall be disposed of properly.
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References
Arizona Department of Transportation (ADOT), Erosion and Pollution Control Manual. 2005.
http://www.azdot.gov/ADOT_and/Storm_Water/Erosion_Pollution_Control_Manual.asp
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp
Federal Energy Regulatory Commission (FERC), Upland Erosion Control, Revegetation, and Maintenance
Plan. January 2003.
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Figure DW -1
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Dust Control (DC)
Description
Dust control involves practices (such as applying water or dust palliatives) to be implemented during
construction operations to prevent dust and wind erosion from exposed soil surfaces.
Applicability
These practices are limited to exposed soil where wind erosion is expected.
Limitations
The effectiveness of this application can be limited by soil, temperature, and wind velocity.
Standards and specifications
Irrigation practices can be applied to a project site until the soil is moist and can be repeated as necessary.
However, the soil shall not be oversaturated causing runoff to flow from the project site. The distribution
system shall be equipped with a proper spray system to ensure even water distribution. When a distribution
system is unavailable, at least one mobile unit shall be available at all times to apply water or a dust palliative
to the project site. All non -potable tanks, pipes, and other conveyances shall be marked "non -potable water -
do not drink."
Seeding, mulching, soil binder, and grading techniques are also temporary methods to prevent dust and wind
erosion. Refer to the applicable BMPs.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspect
protected areas for adequate protection and signs of degradation. Perform spot-checks to ensure dust and
wind erosion control techniques are properly implemented.
References
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp
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Material Delivery and Storage (MDS)
Description
These practices are to be implemented for proper handling, delivery, and storage of materials in order to
prevent spills or leaks into the storm drains or watercourses.
Applicability
These practices are implemented at all construction sites where delivery and storage of materials may be
detrimental to the environment. Materials of concern are not limited to soil, pesticides, herbicides, fertilizers,
petroleum products, asphalt and concrete components, and hazardous chemicals such as acids, paints,
solvents, adhesives, and curing compounds.
Limitations
Space limitation may preclude indoor storage. Storage sheds must meet building and fire code requirements.
Standards and specifications
Deliver and loading/unloading areas
• Keep an accurate, up-to-date inventory of material delivered and stored on site.
• Minimize hazardous material storage on site.
• Employees trained in emergency spill clean-up procedures should be present when dangerous
materials or liquid chemicals are unloaded.
• Cover loading and unloading areas to reduce exposure of materials to rainfall.
• Routinely check vehicles and equipment such as valves, pumps, flanges, and connections for leaks.
• Direct off-site stormwater flows away by grading, berming, or curbing the area around the
loading/unloading area.
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Storage and material handling areas
• Designate storage areas at the project site.
• Locate the storage area away from the storm drain system and watercourses.
• Provide curbs or dikes around the perimeter of material storage areas to prevent run-on from adjacent
areas as well as runoff of stormwater from the material storage areas.
• Prevent spills or leakage of liquid materials from contaminating soil (i.e., soaking into the ground) by
placing storage areas on impervious surfaces.
• Stockpile soil in accordance with the Stockpiling BMP for topsoil and subsoil.
• Store materials indoors within existing structures or sheds when available.
• Material safety data sheets (MSDS) shall be made available for all materials.
• Training for proper material handing and storage techniques shall be required.
• Provide sufficient separation between storage containers to allow cleanup and emergency response.
• Chemically incompatible materials should not be stored together or in the same storage facility.
• Label all materials properly and maintain current legible labels; also maintain a current inventory of all
material delivered and stored.
• Do not store hazardous chemicals, drums, or bagged materials directly on the ground. Place these
items on a pallet and when possible, under cover in secondary containment.
• Keep hazardous chemicals in their original containers and keep them well labeled.
Spill Clean-up
• Immediately contain and cleanup any spills according to the Spill Prevention and Control BMP as well
as the Spill Prevention and Control Countermeasures (SPCC) Plan.
• If significant residual materials remain on the ground after construction is complete, properly remove
and dispose of any hazardous materials or contaminated soil.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspect
equipment and vehicles for leaks. Maintain an ample supply of cleanup materials at all designated storage
and handling areas where leaks and spills are likely to occur. Spot-check material storage and handling areas
for compliance. Material storage areas shall be checked for accumulation of non -labeled materials and spills.
Containment structures or other perimeter controls shall be inspected and repaired when signs of degradation
are visible.
References
Arizona Department of Transportation (ADOT), Erosion and Pollution Control Manual. 2005.
http://www.azdot.gov/ADOT and/Storm Water/Erosion_Pollution_Control_Manual.asp
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp
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Scheduling (S)
Description
Develop a schedule for every project that includes sequencing of construction activities in conjunction with the
implementation of construction site BMPs in order to reduce the amount and duration of soil exposed by
construction activities. The purpose is to minimize erosion of disturbed soils by wind, rain, runoff, and vehicle
tracking by reducing the amount and duration of soil exposed to erosion and ensuring that BMPs are
implemented in a timely manner as construction proceeds.
Applicability
• Construction activities shall be planned to minimize the amount of disturbed land exposed to erosive
conditions.
• Stabilization measures shall be installed and maintained as work progresses, not just at the
completion of construction.
Standards and specifications
• Schedule the installation of temporary and permanent controls as specified in the Construction
General Permit (CGP).
• The schedule of construction activities and concurrent application of temporary and permanent BMPs
is developed as part of the Stormwater Management Plan (SWMP).
• Schedule clearing and grubbing activity to allow existing vegetation to remain in place as long as
possible.
• For larger projects, the contractor shall not expose more than 750,000 square feet in any location until
temporary or permanent BMPs have been installed.
• Schedule shall include dates for significant long-term operations or activities that may have planned
non-stormwater discharges such as dewatering, sawcutting, grinding, drilling, boring, crushing,
blasting, painting, hydro -demolition, mortar mixing, bridge cleaning, etc.
• Schedule shall include dates for installation of permanent drainage systems and runoff diversion
devices. These devices should be installed as early as possible in the construction process.
• The schedule shall include non-stormwater BMPs, waste management, and materials pollution control
BMPs.
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• Stabilize non-active areas as specified in the CGP.
• Monitor weather forecast and adjust construction schedule to allow for the implementation of soil
stabilization and sediment controls on all disturbed areas prior to the onset of rain.
Maintenance considerations
The frequency of inspections should be in accordance with the SWMP. Verify that work is progressing in
accordance with the schedule. The schedule must be updated when changes are warranted or when directed
by the Engineer.
References
Arizona Department of Transportation (ADOT), Erosion and Pollution Control Manual. 2005.
http://www.azdot.gov/ADOT and/Storm Water/Erosion_Pollution_Control_Manual.asp
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SpiII Prevention and Control (SPC)
Description
These practices are implemented to prevent and control spills to ensure that spills and leaks do not result in
water quality impacts.
Applicability
This BMP applies to all construction activities. SpiII prevention and control measures shall be implemented
any time chemicals or hazardous substances are used, stored, or handled.
Limitations
The measures described in this BMP are general. Appropriate practices for specific materials used, stored, or
handled on a project site should be identified by site personnel.
Standards and specifications
The following general design guidelines can be implemented for spill prevention and control measures for
various activities and areas:
• Identify materials delivered, handled, stored, and used at a project site.
• Identify project areas and activities potentially susceptible to spills. Areas and activities that are most
vulnerable to spills include: transportation facilities, loading and unloading areas, fuel and chemical
storage areas, process activities, dust or particulate generating processes, and waste disposal
activities.
• Develop spill response procedures.
SpiII Prevention Control and Countermeasures (SPCC) Plan
A SpiII Prevention Control and Countermeasures (SPCC) Plan has been developed and will be implemented
for certain products that are stored at the site. The SPCC Plan identifies areas where spills can occur on site,
specifies material handling procedures and storage requirements, and identifies spill cleanup procedures. The
purpose of this plan is to establish standard operating procedures and the necessary employee training to
minimize the likelihood of accidental releases of pollutants that can contaminate stormwater runoff. SpiII
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prevention is prudent both environmentally and economically, since spills increase operating costs and lower
productivity.
Emergency spill cleanup plans should include the following information:
• A description of the facility including the nature of the facility activity and general types and quantities
of chemicals stored at the facility.
• A site plan showing the location of storage areas for chemicals, location of storm drains, site drainage
patterns, fire -fighting equipment and water source locations, and the location and description of any
devices used to contain spills such as positive control valves.
• Notification procedures to be implemented in the event of a spill, such as, posting phone numbers of
key personnel and appropriate regulatory agencies.
• Instructions regarding cleanup procedures.
• Designating personnel with overall spill response cleanup responsibility.
• A summary of the plan should be written and posted at appropriate points in the building (i.e., project
trailer and areas with a high spill potential), and shall identify the spill cleanup coordinators, location of
cleanup kits, and phone numbers of regulatory agencies to be contacted in the event of a spill.
• Cleanup of spills should begin immediately. No emulsifier or dispersant should be used. In fueling
areas, absorbent materials should be packaged in small bags for easy use, and small drums should
be available for storage of absorbent and/or used absorbent. Absorbent materials shall not be washed
into the floor drain or storm sewer.
Cleanup response procedures
Response guidelines have been identified below for contractors responding to spills that may potentially result
in an illicit discharge. It is the contractor's responsibility to have all emergency phone numbers available at the
construction site as well to notify the proper response agencies in a timely manner. It is also the contractor's
responsibility to ensure timely and proper cleanup of any spill.
Minor spills
For non—hazardous materials such as gasoline, paint, or oil that may be spilled in small quantities which do
not enter state waters or pose a potential to do so, the following measures shall be implemented:
1. Use absorbent materials to contain spills. Do not hose down spill area with water or bury the spill.
2. Recover spilled materials.
3. Clean the contaminated area of residuals and/or properly dispose of the absorbent material.
Semi -significant spills
For non -hazardous materials that qualify as a semi -significant spill or spills of any size which do not enter
state waters or pose a potential to do so and can be controlled by the first responder along with the aid of other
personnel, the following measures shall be implemented:
1. Notify the project foreman immediately. The foreman should notify the resident engineer.
2. Contain the spills to prevent spreading.
3. If the spills occur on paved or impermeable surfaces, clean-up using "dry" methods (adsorbent
materials, cat litter, and/or rags). Contain the spill by encircling with absorbent materials and do not let
the spill spread widely.
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4. If the spill occurs in a dirt area, immediately contain it by constructing an earthen dike. Dig up and
properly dispose of contaminated material.
5. If the spills occur during rain, cover affected area if possible.
Significant spills
For non -hazardous materials that qualify as a significant spill or spills of any size that enter state waters or
have the potential to do so, the following measures shall be implemented:
1. Contact the Colorado Department of Public Health and Environment (CDPHE) Environmental
Emergency Spill Reporting Line (1-877-518-5608) within 24 hours of the spill event. A written
notification to the CDPHE-Emergency Management Program (EMP) is necessary within 5 days.
2. Contact the Colorado State Patrol 24-hour hotline (1-303-239-4501) if the spill is on a state highway.
3. Notify the project foreman and maintenance personnel on patrol immediately and follow up with a
written report.
4. If possible, cleanup the spill immediately. Use absorbent materials if the material is on an
impermeable surface. Construct an earthen dike to contain a spill on dirt areas. If rainfall is present at
the time of the spill, cover the spill with a tarp to prevent contaminating runoff.
Hazardous spills
For all spills involving hazardous materials, the following measures shall be implemented:
1. Contact the local emergency response team by dialing 911.
2. Contact the CDPHE-EMP 24 Environmental Emergency Spill Reporting Line (1-877-518-5608) within
24 hours of the spill event. A written notification to the CDPHE-EMP is necessary within 30 days.
3. Contact the Colorado State Patrol 24-hour hotline (1-303-239-4501) if the spill is on a state highway.
4. Report spills to project foreman and maintenance personnel on patrol and follow up with a written
report.
5. Construction personnel shall not try to clean up the spill.
6. Cleanup spill immediately; a licensed contractor or HazMat team shall be used to properly clean up
spills.
Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan. Inspect
equipment and vehicles for leaks. Maintain an ample supply of cleanup materials at all designated
maintenance areas where leaks and spill are likely to occur. Spot-check material storage and handling areas
for compliance. Material storage and use areas shall be checked for accumulation of non -labeled materials
and spills. Identify spills or leaks into to the storm drain at or near work areas. Containment structures or
other perimeter controls shall be inspected and repaired when signs of degradation are visible.
References
Arizona Department of Transportation (ADOT), Erosion and Pollution Control Manual. 2005.
http://www.azdot.gov/ADOT and/Storm Water/Erosion_Pollution_Control_Manual.asp
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide.
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Waste Management (WM)
Description
Stormwater runoff from areas where construction wastes are stored or disposed can be polluted. Wastes
leached or spilled from management areas may build up in soils or on other surfaces and be carried by
stormwater runoff. The optimal approach to reduce the potential for stormwater contamination from wastes is
to reduce the amount generated and, consequently, the amount stored on site. The following types of waste
management are covered under this BMP:
Concrete waste management: Practices to be used in order to minimize and prevent concrete waste
associated with construction activities from entering storm drains and watercourses. Concrete waste may be
generated where concrete trucks or concrete -coated equipment are washed on site, where slurries containing
concrete are generated, or where mortar -mixing areas exist.
Solid waste management: Practices to be used in order to minimize and prevent solid waste associated with
construction activities from entering storm drains and watercourses. Solid waste can be classified as non-
hazardous solid material including: concrete, rock, debris, soil, wood, vegetative material, plastic, fabrics,
mortar, metal scraps, Styrofoam, and general litter such as but not limited to beverage containers and plastic
wrappers.
Sanitary and septic waste management: Practices to be used in order to minimize and prevent sanitary and
septic waste associated with construction activities from entering storm drains and watercourses.
Liquid waste management: Practices to be used in order to minimize and prevent liquid waste associated with
construction activities from entering storm drains and watercourses.
Hazardous waste management: Practices to be used in order to prevent hazardous waste associated with
construction activities from entering storm drains and watercourses. Hazardous wastes may be discovered or
generated (by lead paint removal operations) and are designated as hazardous by the Code of Federal
Regulations or Colorado state laws.
Contaminated waste management: Practices to be used in order to minimize and prevent pollutants from
contaminated soils from leaching into watercourses or drainage systems.
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Applicability
Facilities or designated construction work areas where each type of waste is discovered or generated.
Limitations
During the non -rainy season or in arid portions of the state, temporary stockpiling of non -hazardous solid
waste may not require stringent drainage control measures. The engineer for the project shall determine if
drainage control measures are warranted for a specific construction site where non -hazardous solid waste is
being stockpiled.
Liquid waste management does not apply to solid wastes, hazardous wastes, concrete slurries/wastes,
dewatering operations, sanitary/septic wastes, or permitted allowable non-stormwater discharges. Disposal of
some liquid wastes may be subject to regulations or requirements of other permits secured for the construction
site.
This BMP provides general hazardous waste management guidelines, but does not relieve the contractor from
full responsibility of complying with federal, state, and local laws regarding storage, handling, transportation,
and disposal of hazardous wastes. It is the contractor's full responsibility to identify all hazardous waste
generated at the project site.
The contractor is responsible for identifying pollutant -specific handling and disposal procedures for
contaminated soils at the project site.
Standards
Concrete waste
Waste generated from concrete activities shall not be allowed to flow into drainage ways, inlets, or receiving
waters.
Concrete waste shall be placed in a temporary concrete washout facility.
• Concrete washout facilities will be comprised of an excavation with erosion bales and construction
fences along the perimeter. The facility may be similar to the settling device used for dewatering (see
Figure DW -1). The bottom of the excavation must be proven to be at least 5 vertical feet above
groundwater or, alternatively, the excavation must be lined with either a clay or synthetic liner that is
designed to control seepage. The facilities shall be maintained in good condition to contain all liquid
and concrete waste generated by operations at a project site.
• Proper signage such as "Concrete Washout" shall be placed near concrete washout facilities to inform
construction personnel of the location of designated concrete washout facilities.
• Temporary concrete washout facilities shall be located 50 horizontal feet from drainageways, inlets,
and receiving waters unless otherwise approved by the engineer.
• Adding solvents, flocculents, or acid to washwater is prohibited.
• Whenever a concrete washout area is within 300 feet of the access to a road or highway, a stabilized
construction entrance must be built as part of the washout, or at the entrance to the road or highway.
• Hardened concrete waste shall be properly disposed of following solid waste management
procedures.
• Removal of temporary facilities, including the solid concrete waste and the material used to construct
the facilities, shall be the responsibility of the contractor, who shall remove the waste from the project
site and dispose of it properly following guidelines outlined in solid, liquid waste management and any
applicable regulations.
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Solid waste
• Litter shall be minimized at all construction sites and collected on a weekly basis into water -tight
dumpsters. Trash receptacles shall be provided in various locations within the construction site
boundaries.
• Collected trash shall not be placed near drainage inlets or watercourses.
• A trash hauling contractor shall be used to properly dispose of the collected waste in a timely manner.
Dumpster washout at the construction site is not permissible.
• Priority shall be given to remove waste and debris from drainage inlets, trash racks, and ditches in
order to prevent clogging of the stormwater system.
• Waste storage areas shall be pre -approved by the engineer.
• Storage areas for solid waste shall be located at least 50 feet from drainageways and watercourses,
and shall not be located in areas susceptible to frequent flooding. Sediment barriers such as berms,
dikes, or other temporary diversion structures shall be used to prevent stormwater runoff from
contacting stored solid waste at the project site.
• Solid waste shall be segregated properly into various categories for recycling or disposal. Proper
disposal is required for each waste category. The contractor shall make every attempt to recycle
useful vegetation, packaging material, and surplus construction materials when practical.
• Most construction materials can be recycled at recycling facilities.
Septic and sanitary waste
• Temporary sanitary facilities shall be located away from drainage ways, inlets, receiving waters, areas
of high traffic, and areas susceptible to flooding or damage by construction equipment.
• Temporary sanitary facilities shall be properly connected into a sanitary sewer system where
permissible to prevent illicit discharges. Authorized sanitary sewer system connections shall comply
with local health agency, county, and sanitary sewer district requirements.
• Wastewater generated from sanitary facilities shall not be allowed to flow into drainageways, inlets, or
receiving waters.
• Only licensed sanitary/septic waste haulers shall be used to properly dispose of waste from temporary
sanitary facilities.
• In project areas susceptible to strong winds, temporary sanitary facilities shall be secured to prevent
overturning.
Liquid waste
• The contractor shall oversee and enforce all liquid waste measures and will instruct all employees and
subcontractors on the identification of hazardous and non -hazardous liquid waste, and non -hazardous
handling, storage, and proper disposal.
• The contractor shall hold regular safety meetings to ensure proper liquid waste measures are being
adhered to and efforts are being made to minimize the amount of liquid waste produced.
• The contractor shall ensure compliance with all liquid waste management procedures and practices.
• Liquid wastes generated from operational procedures such as drilling residue and fluids shall not be
allowed to flow into drainageways, inlets, or receiving waters.
• All liquid wastes shall be contained in designated areas such as sediment basins, holding pits, or
portable tanks. Designated containment areas shall be located away from drainageways, inlets,
receiving waters, areas of high traffic, and areas susceptible to flooding.
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• Precautions shall be taken to ensure that proper spill prevention and control measures are being
implemented to avoid accidental spills.
• If a liquid waste is released or spilled, capture the liquid with proper cleanup methods. Do not allow
the liquid waste to flow uncontrolled or into drainageways, inlets, and receiving waters. Use diverting
methods such as temporary dikes to control the spill and direct it to containment areas for capture.
• The contractor shall be responsible for adhering to all permit requirements, federal, state, and local
regulations for properly disposing liquid waste.
Hazardous waste
The following are general guidelines provided for planning the management of hazardous wastes.
• Hazardous waste storage, transportation, and disposal shall comply with 49 CFR 172, 173, 178, 179,
and 261-263, and state regulations.
• Special materials and equipment may be required to manage wastes that are corrosive, combustible,
flammable, oxidizer, poison, toxic, or reactive. Clearly label all waste containers with the appropriate
description of the wastes being contained.
• Hazardous wastes shall be segregated, and incompatible or reactive wastes shall be disposed of
properly in a manner to prevent fires and explosion. Always consult the health and safety officer,
engineer, and/or project manager prior to mixing hazardous wastes for disposal. Hazardous waste
shall be segregated properly into various categories such as liquids, semi -liquids, and solids.
• Select the most appropriate disposal container to store the hazardous waste. Additionally, select a
container that is compatible with the hazardous material being stored. For instance, use plastic or
plastic -lined steel drums for storing corrosive materials. Corrosive materials will react with steel and
cause the waste to be released from the drum. Always consult the engineer or project manager to
ensure that the container and waste are compatible.
• Waste containers shall be stored and managed in temporary containment facilities that shall meet the
following requirements:
A spill containment volume 1.5 times the volume of all containers
Impervious to the materials contained for a minimum contact time of 72 hours
— Free of accumulated rainwater or spills, with sufficient separation provided between stored
containers to allow for spill cleanup
Incompatible, ignitable, and reactive materials shall not be stored in the same temporary
containment facility
"Caution: Flammable Material" signs must be posted near containment areas to prevent fires or
explosions
• The following management guidelines are recommended for containment facilities:
Keep containers closed at all times except when adding or removing waste from the container.
Use a funnel or hose to transfer wastes to drums.
You must open, handle, and store containers to prevent ruptures or leaks. Make sure to open
drums with a spark -proof wrench.
- If the container begins to leak or you notice dents or bulges, transfer the waste to another
container.
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• Locate containment areas away from high -traffic areas, waterways, drainage inlets, sensitive habitats,
and areas prone to flooding or ponding.
• Waste residuals from equipment or brushes shall be cleaned in designated containment areas and
shall not be allowed to seep into soils causing soil contamination or to discharge into watercourses or
drainageways.
• Secondary containment needs to be provided for all hazardous waste containers. In addition,
containment berms shall be used in fueling and maintenance areas where the potential for spills is
high.
• Hazardous waste containment areas shall be pre -approved by the engineer and/or project manager.
• It is the contractor's responsibility to ensure that all hazardous waste discovered or generated at a
project site is disposed of properly by a licensed hazardous material disposal contractor/facility utilizing
properly completed Uniform Waste Manifest forms. The contractor is responsible for not exceeding
hazardous waste storage requirements mandated by the state or other localities.
• Additional disposal guidelines for non -hazardous solid and liquid waste are included in Sections WM 2
and WM 4, respectively.
Contaminated waste
The following are general guidelines provided for planning the management of contaminated soils.
• The contractor is responsible for reviewing relevant environmental reports, appropriate plans, and
project special provisions for contaminated soils information. The contractor shall also take initiative to
further inform the engineer of any potential or identified contaminated soils on the project site.
• Contractor and employees are responsible for meeting safety training requirements mandated by
29 CFR 1910.120 prior to performing any construction work or excavation at projects sites where
contaminated soils have been classified as hazardous materials.
• The contractor is responsible for following all rules and regulations applicable to the excavation,
handling, transport, and disposal of contaminated and hazardous materials. The applicable rules and
regulations are not limited to the standards of Occupational Safety and Health Administration,
U.S. Environmental Protection Agency, U.S. Department of Transportation (USDOT), Colorado
Department of Public Health and Environment (CDPHE), and local agencies.
• Contaminated soils should be placed in a lined and bermed area.
• Surround the perimeter of the exclusion zone with a security fence for safety.
• Collect impacted soil samples and complete a characterization analysis.
• Collect non -reusable protective equipment used at the project site and dispose of it properly.
Additionally, treat and/or dispose of wastewater from decontamination procedures.
• Contaminated soil shall be transported to a licensed disposal facility on vehicles registered for that
purpose.
• When an underground storage tank is discovered at a construction site, coordinate with the regional
environmental project manager for guidance on handling and disposal procedures.
• Preventive measures, such as berms, freeze walls, cofferdams, and grout curtains, should be installed
to prevent stormwater runoff or groundwater from mixing with hazardous materials or underground
tank excavations. Water exposed to contaminated areas should be placed in water -tight holding tanks,
tested, and properly disposed.
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Maintenance considerations
The frequency of inspections should be in accordance with the Stormwater Management Plan.
The contractor shall monitor concrete activities to ensure proper waste management techniques are being
utilized. Maintenance of temporary concrete washout facilities shall include removing hardened concrete and
proper disposal. It is recommended that facilities be cleaned out once they are 75 percent full, or new facilities
shall be constructed to provide additional concrete waste storage.
Check for and remove litter and debris from drainage grates and other drainage structures. Provide cover for
dumpsters and waste containers to prevent entry of rainwater and loss of contents by high winds.
Inspect perimeter controls, containment structures, berms, covers, and liners. Repair or replace as needed to
function properly.
The contractor shall be responsible for monitoring on-site contaminated storage and disposal procedures.
References
Arizona Department of Transportation (ADOT), Erosion and Pollution Control Manual. 2005.
http://www.azdot.gov/ADOT and/Storm Water/Erosion_Pollution_Control_Manual.asp
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
http://www.dot.state.co.us/environmental/envWaterQual/wgms4.asp
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June 2008
Vehicle and Equipment Management (VEM)
VEHICLE
-- WASH
AREA
1=11 icRWA
Description
Procedures and practices used to minimize or eliminate the discharge of pollutants during the following
operations:
• Cleaning of vehicles and equipment prior to or during use on project site.
• Fueling of vehicles.
• Maintenance of vehicles and equipment.
Applicability
These procedures are applied on all construction sites where vehicle and equipment cleaning, fueling, and/or
maintenance takes place.
Limitations
Only use on-site vehicle and equipment fueling when it is impractical to send vehicles and equipment off site to
be refueled. Comply with local codes and ordinances regarding the disposal of fluids and consumables, and
the on-site maintenance of equipment.
Standards and specifications
Vehicle and equipment cleaning
• On-site vehicle and equipment washing is discouraged, but may be necessary to eliminate spread of
invasive species to areas outside of project site.
• Cleaning of vehicles and equipment with soap, solvents, or steam shall not occur on the project unless
the Engineer has been notified in advance and the resulting wastes are fully contained and disposed
of outside of the highway right-of-way in conformance with the Standard Specifications. Resulting
wastes shall not be discharged or buried.
• When equipment/vehicle washing/cleaning must occur on site and the operation cannot be located
within a structure or building equipped with appropriate disposal facilities, the outside cleaning shall
have the following characteristics and shall be arranged with the Erosion Control Coordinator:
— A washout area shall be an excavated pit, which will later be backfilled or where the concrete
wash can harden and be properly disposed of.
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June 2008
— Locate wash out areas close to the active construction site on the project.
Locate wash out pits away from storm drains, open ditches, or receiving waters.
— Use only when necessary.
When cleaning vehicles/equipment with water use as little water as possible. Consider using
high pressure sprayers, which require less water.
Vehicle and equipment fueling
• When fueling must occur on site, the contractor shall select and designate an area to be used, subject
to approval by the Engineer.
• Federal, state, and local requirements shall be observed for any stationary aboveground storage
tanks.
• Mobile fueling of construction equipment throughout the site shall be minimized. Whenever practical,
equipment shall be transported to the designated fueling area.
• Spill prevention, containment, and countermeasures shall be included in the Stormwater Management
Plan (SWMP) if the volume of project site fuel in a single container exceeds 660 gallons, or if the total
fuel storage volume at any one site exceeds 1,320 gallons.
• Designated fueling areas shall be protected from stormwater runoff and shall be located at least 50
feet from downstream drainage facilities or watercourses. Fueling must be performed on level -grade
areas.
• Protect fueling areas with berms and/or dikes to prevent run-on, runoff and to contain spills.
• Absorbent spill clean-up materials and spell kits shall be available in fueling areas and on fueling
trucks and shall be disposed of properly after use.
• Drip pans or absorbent pads shall be used during vehicle and equipment fueling, unless the fueling is
performed over an impermeable surface in a dedicated fueling area.
• Nozzles used in vehicle and equipment fueling shall be equipped with an automatic shut-off to control
drips. Fueling operations shall not be left unattended. Fuel tanks shall not be "topped off."
Vehicle and equipment maintenance
• Plan for the proper recycling or disposal of used oils, hydraulic fluids, gear lubricants, batteries, and
tires.
• Use appropriate, leak -proof containers for fuels, oils, and lubricants to provide for proper disposal.
• Use steam or high-pressure water instead of thinners and solvents to wash down equipment. Wash
water and detergents can be disposed of in the sanitary sewer system after grit is removed, after
checking with local authorities.
• Use drip pans or absorbent pads under equipment during maintenance that involves fluids.
• Equipment maintenance and wash-out areas should be located at least 50 feet away from drainages.
• Provide spill containment areas around stored oil and chemical drums.
• Provide a contained wash-out area to wash down heavy equipment.
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Maintenance considerations
The frequency of inspections should be in accordance with the SWMP. Vehicles and equipment shall be
inspected for leaky gaskets and damages hoses. Leaks shall be repaired immediately or problem vehicles or
equipment shall be removed from the project site. Any damaged hoses shall be repaired or replaced as
needed. Fueling areas and storage tanks shall be inspected. Immediately clean up spills and properly
dispose of contaminated soil and cleanup materials. Inspect equipment maintenance areas and wash-out
areas. Inspect fluid containers for leaks. Repair leaky fluid containers immediately.
References
Arizona Department of Transportation (ADOT), Erosion and Pollution Control Manual. 2005.
http://www.azdot.gov/ADOT_and/Storm_Water/Erosion_Pollution_Control_Manual.asp
Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002.
http://www.dot.state.co.us/environmental/envWaterQual/wqms4.asp
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Appendix F
Oil and Gas Construction Field Permit Certification NOTICE OF
AMENDMENT OF PERMIT COVERAGE and/or Final Stabilization
Certification
F:\Projects\014-2797\Documents\O pe rati on a l
Docs\SWMP\1. Mamm_Creek_SWMP_20101210.doc
Updated February 2008
STATE OF COLORADO
Oil and Gas Construction Field Permit Certification
NOTICE OF AMENDMENT OF PERMIT COVERAGE
Terminating coverage for a portion of a permitted area
GENERAL PERMIT FOR
STORMWATER DISCHARGES ASSOCIATED WITH CONSTRUCTION ACTIVITY
This form is for construction activities associated with oil and gas construction only. The form is
applicable to field permit certifications only, and is not applicable to construction activities for other
sectors, such as residential, commercial, or transportation. Additional options for administration and
amendments for construction permits, including for activities not associated with oil and gas, is
available on the Division's permitting web page, coloradowaterpermits.com (follow the link to
"Stormwater Permitting," and then "Construction Stormwater").
This form is to be used to amend an oil and gas field permit certification under Colorado's Stormwater
Construction Permit, to terminate permit coverage when all of the following conditions have been
met:
1. The permit certification to be amended is a field permit certification for construction associated
with oil and gas construction. The field permit covers all construction activities disturbing over one
acre, or that are part of a common plan of development exceeding one acre, within the applied -for
field.
2. The area is a distinct and separate area where construction has been completed and is not part of a
specific facility, such as a single well pad or road segment, where construction is ongoing.
3. The area must be Finally Stabilized. An area is Finally Stabilized when all ground surface
disturbing activities at the site have been completed, and all disturbed areas have been either built
on, paved or equivalently hard -armored, or a uniform vegetative cover has been established with an
individual plant density of at least 70 percent of pre -disturbance levels.
Upon acceptance of this notice by the Water Quality Control Division (the Division), the permit
certification will be automatically amended to exclude the specific portion described in the notice. The
current permittee will not receive a revised certification. The corrected information will be placed
in the permit file. In order to receive notification of the Division's receipt of this information, it is up
to the permittee to request verification of delivery from the carrier (i.e., by sending certified mail).
If the Area Has Not Been Finally Stabilized: This form is only for terminating an area that has been
finally stabilized. If the area has not been finally stabilized the permittee must either maintain permit
coverage, or can reassign permit coverage to another entity that owns or has operational control over
that area. The Division's Notice of Reassignment of Permit Coverage form should be used. The form
is available at coloradowaterpermits.com
Stormwater Management Plan (SWMP): The permittee must maintain a SWMP that accurately
reflects the activities and BMPs for the areas for which they will have permit coverage. Therefore, the
SWMP must be updated to reflect the changes described in this form. Appendix A of the General
Permit Application and SWMP Guidance for Stormwater Discharges Associated with Construction
Activity (available from the Division's web site at coloradowaterpermits.com) contains the
requirements for the SWMP.
Failure by the permittee to maintain a SWMP in accordance with this guidance is a violation of the
permit. Additional guidance for multi owner/operator development is also available in the Stormwater
Fact Sheet for Construction, available from the Division's web site.
12/08/OGcoverageamend
Notice Due Dates: At least ten days prior to the requested effective date for permit coverage to end,
the permittee shall submit this form to the Division. This form may be reproduced, and is also
available from the Division's web site at coloradowaterpermits.com.
Permit Fee: There are no new permit fees associated with amending the construction permit
certification.
Application Completeness: All items on the form must be completed accurately and in their entirety
or the notice will be deemed incomplete, and processing of the form will not begin until all information
is received. A map of the revised area must be included that clearly indicates the area with continued
coverage under the permit certification, and the area excluded. (Do not include a copy of the SWMP.)
One original copy of the completed form (no faxes or e-mails), signed by the current permittee, shall
be submitted, only to:
Colorado Department of Public Health and Environment
Water Quality Control Division - Permits
4300 Cherry Creek Drive South
Denver, Colorado 80246-1530
If you have questions on completing this application, you may contact the Division at
cdphe.wqstorm@state.co.us or (303) 692-3517.
SITE MAP INSTRUCTIONS
Site Map: A Site Map must be provided. The map must clearly define the boundaries of the area to
be excluded from permit coverage relative to that with continued coverage. The level of detail that
must be provided will depend on the nature of the project, and must be adequate to determine during a
field audit what construction activities are still covered under the issued certification. Two maps (a
vicinity map and excluded site boundary map) may be necessary to provide sufficient detail to meet
this requirement for large field areas. Maps must not exceed 8 Y2 x 17 inches. Do not submit grading
plans or other blueprints as the site map.
12/08/OGcoverageamend
Colorado Department of Public Health & Environment FOR AGENCY USE ONLY
Water Quality Control Division
WQCD-P-B2 REC
4300 Cherry Creek Drive South EFF
Denver, Colorado 802464530 YEAR MONTH DAY
Amendment notice for
Oil and Gas Construction Field Permit Certification
CONSTRUCTION STORMWATER DISCHARGE GENERAL PERMIT CERTIFICATION
Please print or type. Form must be filled out completely.
Certification Number: COR -03 1234
Permittee (Company) Name:
Permittee Address:
Phone No.
Field Permit Certification Information (refer to your permit certification):
Field Permit Site/Facility Name: County(s):
Contact Person:
Contact Person Phone No.: Contact Person Email:
Information on Area to be Excluded from Permit Coverage:
Site Map: Must include Site Map indicating the boundaries of the area to be excluded from permit coverage.
Refer to the Site Map Instructions on page ii of this form. Maps must be folded to 8% x 11 inches.
Map enclosed? Yes No
Summary of work performed and description of final stabilization for the area shown in the attached map:
I certify under penalty of law that by the date of my signature below, at the identified construction site area, all disturbed soils have
been finally stabilized; all temporary erosion and sediment control measures have been removed; all construction and equipment
maintenance wastes have been disposed of properly; and all elements of the Stormwater Management Plan have been completed.
I understand that by submitting this notice of amendment, I am no longer authorized to discharge stormwater associated with
construction activity by the general permit, for this specific area. I understand that discharging pollutants in stormwater associated
with construction activities to the waters of the State of Colorado, where such discharges are not authorized by a CDPS permit, is
unlawful under the Colorado Water Quality Control Act and the Clean Water Act.
I certify under penalty of law that I have personally examined and am familiar with the information submitted herein, and based on my
inquiry of those individuals immediately responsible for obtaining the information, I believe that the information is true, accurate and
complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and
imprisonment. (See 18 U.S.0 1001 and 33 U.S.C. 1319.)
Signature of Permit Applicant (Legally Responsible Party) Date Signed
Name (printed) Title
12/08/OGcoverageamend
Encana SWMP — Final Stabilization Certification
Date:
Site ID:
Type of Area:
❑ Well Pad
❑ Access Road to Well Pad
❑ Other Road
❑ Pipeline
❑ Other Facility
"The above referenced site has reached final stabilization. All ground surface
disturbing activities have been completed, including the removal of all temporary
BMPs, and all disturbed areas have been either built on, or a uniform vegetative
cover has been established with an individual plant density of at least 70 percent
of pre -disturbance levels, or equivalent permanent, physical erosion reduction
methods have been employed."
Printed name Title
Signature Date
Appendix G
Inspection and Maintenance Report Form
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Updated February 2008
EnCana SWMP Inspection and Maintenance Report Form
Area Inspected (Site ID):
Title of Inspector: Name of Inspector: Date:
Type of Area: Well Pad I- Access Road to Well Pad [ Other Road I- Pipeline I Other Facility:
Phase of Construction: I Preconstruction onstruction P rifling f ompletions
P Reoccupy I- :erm Reclamation I- inal Reclamation
Type of Inspection: 7 Active (14 days since last inspection) I ompleted (1 month since last inspection)
I Active (Within 24 hours of a rain/snowmelt event that causes surface erosion or 72 hours for temporarily idle sites)
Winter Conditions Exist
Site Specific Information
Approximate area of site to be disturbed (acres): Receiving Water(s):
Soil Type(s):
Ecosystem/Vegetation Type(s):
Other Site Specific Information:
Vegetation Observations
Site Revegetated: Yes I No P Current Vegetation: %
Pre -disturbance Vegetation: % (estimate from undisturbed surrounding areas)
Vegetation Growth uniform and at least 70% of pre -disturbance levels: Yes F Jo F
Best Management Practice (BMP) Check List
Erosion Control:
In Use?
Comments
Drainage Control:
In Use?
Erosion Control Blanket
P
Berm
Hydraulic Mulching
I-
Culvert
Land Grading - Roads (slopes/gravel/etc)
I-
Culvert Inlet Protection
Mulching
P
Culvert Outlet Protection
Retaining Wall
I
Diversion
Revegetation
f
Drainage Dip
Riprap
I
Level Spreader
Soil Stabilizers
Roadside Ditches and Turnouts
Stockpiling - Topsoil and Subsoil
P
Run On Diversion
Surface Roughening
I
Slope Drain
Terracing
I
Trench Breaker
I
Turf Reinforcement Mat
Water Bar
Vegetated Buffer
I
Wattles
Sediment Control:
In Use?
Comments
Sediment Control:
In Use?
Check Dam
Slash
f
Detention Pond
I
Stabilized Construction
Filter Berm
1
Straw Bale Barrier
f
Sediment Reservoir
Riprap
Sediment Trap
1
Wattles
Silt Fence
I-
r
Non-Stormwater Control:
In Use?
Comments
Non-Stormwater Control:
In Use?
Dewatering
Dust Control
Location/Observation:
Additional Comments: New BMPs installed , changes, dates performed, etc...)
Site perimeter/discharge points inspected? Yes I- No I- N/A P
All disturbed areas inspected? Yes I- No I- N/A I -
Vehicles entrance(s)/exit(s) inspected? Yes I- No I- N/A I -
Material storage areas inspected? Yes I No 1- N/A (-
Acceptable waste management procedu res? Yes I- No I- N/A 1 -
Acceptable
Acceptable vehicle/equipment maintenance? Yes I- No I- N/A I
Any sediment/pollutant discharged off-site? Yes fl No E N/A I^
If no change since above inspection (no changes to BMPs or SWMP)
Date Signature
Type of Inspection
14 day I Monthly Pptn. Event I-
14 day I Monthly I- Pptn. Event I-
14 day I Monthly 1 - Pptn. Event I-
14 day P Monthly I Pptn. Event f
14 day I- Monthly I- Pptn. Event
Signature certifying that the site is in compliance (after all necessary repairs, maintenance, and changes have been made):
Date
Signature
Appendix H
Inactivation Form
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Updated February 2008
Colorado Department of Public Health & Environment FOR AGENCY USE ONLY
Water Quality Control Division
WQCD-P-B2 REC
4300 Cherry Creek Drive South EFF
Denver, Colorado 80246-1530 YEAR MONTH DAY
INACTIVATION NOTICE FOR
CONSTRUCTION STORMWATER DISCHARGE GENERAL PERMIT CERTIFICATION
Please print or type. Form must be filled out completely.
Certification Number: COR -03
Permittee (Company) Name:
Permittee Address:
Site/Facility Name:
Taxpayer ID or EIN
Phone No. (
Construction Site Address/Location:
County: Contact Person:
Summary of work performed and description of final site stabilization:
I certify under penalty of law that by the date of my signature below, all disturbed soils at the identified construction site
have been finally stabilized; all temporary erosion and sediment control measures have been removed; all construction
and equipment maintenance wastes have been disposed of properly; and all elements of the Stormwater Management
Plan have been completed.
I understand that by submitting this notice of inactivation, I am no longer authorized to discharge stormwater associated
with construction activity by the general permit. I understand that discharging pollutants in stormwater associated with
construction activities to the waters of the State of Colorado, where such discharges are not authorized by a CDPS
permit, is unlawful under the Colorado Water Quality Control Act and the Clean Water Act.
I certify under penalty of law that I have personally examined and am familiar with the information submitted herein, and
based on my inquiry of those individuals immediately responsible for obtaining the information, I believe that the
information is true, accurate and complete. I am aware that there are significant penalties for submitting false
information, including the possibility of fine and imprisonment. (See 18 U.S.0 1001 and 33 U.S.C. 1319.)
Signature of Permit Applicant (Legally Responsible Party) Date Signed
Name (printed) Title
9/97/cn/in