HomeMy WebLinkAboutEngineer's OWTS Design PlanMarch 10, 2026
502 Main Street • Suite A3 • Carbondale, CO 81623 • (970) 704 -0311 • Fax (970) 704 -0313
S OPRIS E NGINEERING • LLC civil consultants
Leonard Olim
Big Lenny's Storage Rifle LLC,
5458 Mount Vernon Parkway
Atlanta, GA 30327 PO Box 2834
Angela Newman <newmanangela2015@gmail.com>
Leonard olim <biglennyolim@gmail.com>
C/o Myrl Serra <5mconst.llc@gmail.com>
RE: OWTS Design Report, On-site Wastewater Treatment System (OWTS ), Big Lenny's Storage Rifle
LLC, 184 Gas Court, Rifle , Garfield County, CO
SE Job No. 346016.01 , Parcel No: 217718201004 . New Garfield County Permit # ____________
Dear Leonard, Angela and Myrl:
This letter report presents the applicable findings regarding the design and construction of a new Onsite
Wastewater Treatment System (OWTS) at the above referenced Site, in support of your building permit
application to Garfield County. A new OWTS construction permit is required for the proposed usage on
the subject property.
The OWTS design is based on our evaluation of the site conditions for use in obtaining a Garfield County
OWTS construction permit. We have evaluated the existing and proposed site conditions with respect to
the operation and installation of a new OWTS in accordance with County OWTS Regulations and State of
Colorado Regulation 43. The new system meets all required setback requirements and operational
demands for the proposed usage. Based on the physical site features, soils, and proposed building layout,
we have prepared a civil OWTS design plan with construction details for permit approval. The design
drawing is based on a GIS aerial mapping, previous Sopris Engineering Existing Conditions Plat S urvey
and Lidar topography. The design and construction recommendations with specifications are delineat ed on
the civil design plans, C1-DE-OWTS Plan dated 0 3-10-2026, by Sopris Engineering.
OWTS Conditions and Design Criteria
Proposed OWTS System
Proposed site improvements and expected usage result in a design flow of 270 gpd. The system will be
constructed to provide for demand dosing of septic tank effluent to an engineered soil treatment area
(STA ), pursuant to Regulation 43 design criteria. The OWTS will include a gravity service pipe from the
commercial shop facil ities building to a new 1000-gallon concrete septic tank equipped with a high head
effluent pump assembly.
The system is designed based on the current design criteria for the use of a pressure dosed chamber trench
system. The STA area calculations are based on the design flow , LTAR loading rate for the in-situ soils
utilizing applicable multiplier loading rates for Table 10.3, Category 3 distribution media consisting of
shallow pressure dosed chamber trenches installed over native soil.
The system will include the installation of an Orenco System bio tube effluent pump assembly for pressure
distribution of septic tank effluent to a new pressure dosed chamber trench system . The effluent discharge
piping will be installed to connect to a pressurized manifold connecting to the head of each chamber trench
OWTS Design and Construction
184 Gas Court, Rifle, Garfield County
SE Job No. 34132 .01
March 10, 2026
Page 2
row with custom perforated distribution laterals. Each chamber trench will have appropriate inspection
port cleanouts and appurtenances.
Design Calculations OWTS
The design flow is calculated as follows for a commercial shop/office facility onsite wastewater treatment
system (OWTS). The treatment capacity is designed for an equivalent 9 shop/office facilities with an
assumed 2 employees each.
From the Regulation 43 usage table :
Minimum population based on 9 offices = 18 staff employees.
Gallons per day per person =15 gal/employee/day,
Max. Design flow (Qd)gallons/day = (# of people) x (avg. flow)gal/person/day.
Design flow Qd = 18*15=270 gpd
Septic Tank Design: 2-Day detention time = 270 x 2 = 540 gallons required.
Use a deep bury reinforced 1000 gallon, two compartment concrete septic tank with a high head pump
assembly in the second compartment.
Sub Surface Conditions and Testing:
A subsurface soil investigation and site assessment was performed by Sopris Engineering in on February
13, 2026. The soils were sampled and characterized by application of the USDA visual/tactile soil texture
method analysis from samples in two profile pits. Two excavated profile pits 1 & 2 were observed in the
East central portion of the site adjacent to the proposed soil treatment area field location. The soils below 4
to 9 inches of mixed surface fill & gravels consist of medium dense sandy clay loam with moderate
granular to slightly blocky structure with some cobbles and gravels to depths of 1.5 to 2.0 feet underlain by
dense slighty sandy clay loam with less than 5% of total rock content to the 8 foot depth explored in both
pits. The soil appears to be generally consistent across the site. No evidence of seasonal high ground
water, redox conditions or any other limiting conditions were observed in the profile pits. Groundwater
levels are expected to be below 20 feet from the existing surface grades on the relatively flat terrain. The
soils are suitable for a shallow conventional absorption field consisting of gravelless infiltration chamber
units.
Profile Pit-1
The soils below approximately 4 inches of surface gravels consist of moderately dense sandy clay loam
texture fill material with gravels and cobbles that has blocky to granular shape of moderate structural grade
to a depth of 2-feet containing approximately 40% total rock content. Soils below 2 feet underlying the
mixed fill consist of dense slighty sandy clay loam texture soil that has granular to massive structure of
weak structural grade with less than 5% of total rock content to the 8 foot depth explored. The soils are
characterized as a soil type 3A Sandy clay loam. No free water or limiting condition was encountered in
the pit excavation.
OWTS Design and Construction
184 Gas Court, Rifle, Garfield County
SE Job No. 34132 .01
March 10, 2026
Page 3
Profile Pit-2
The soils below approximately 3 inches of surface gravels consist of moderately dense sandy clay loam
texture fill material with gravels and cobbles that has blocky to granular shape of moderate structural grade
to a depth of 1-foot containing approximately 40% total rock content. Soils below 1.5 feet underlying the
mixed fill consist of dense slighty sandy clay loam texture soil that has granular to massive structure of
weak structural grade with less than 5% of total rock content to the 8 foot depth explored. The soils are
characterized as a soil type 3A Sandy clay loam.No free water or limiting condition was encountered in the
pit excavation.
The native soils sampled from 2-4 feet below the surface, in both profile pits, are characterized as a soil
type 3A soil type consisting of slighty sandy clay loam texture soil with granular to massive structure of
weak structural grade. The tan to grayish sandy clay loam soil tactile test ribbons were 1 ¾-inch long. Soil
type 3A has an effective loading rate for conventional soil treatment of 0.30 gal/S.F./day for a level 1
conventional treatment system. The equivalent percolation rate of these soils is assumed to be 61-75
minutes per inch.
Additional observations will be performed during construction to inspect the shallow trench chamber
trench excavations, absorptive surface preparation in the soil treatment area and provide guidance for
installations of the specified materials in the in-situ native soils. If any adjustments to design or installation
recommendations are necessary, notice will be made to County EHD and applicable revisions to
design/construction plans and report will be submitted. All conditions and installations will be included in
the As-Constructed documentation.
Chamber Treatment Unit/ Absorption System Design
The treatment/absorption trenches are designed based on utilizing the effective Long Term Acceptance
Rate (LTAR) for native soils and the application of appropriate loading factors for a treatment level-1
system utilizing pressure dosed chamber trenches. The new treatment system will consist of pressure dosed
chamber trenches with custom perforated distribution laterals, in accordance with Regulation 43 sections
(43.10(C), 43.13.E.1.d, Table 10-2 and Table 10-3 as approved by CDPHE for this technology.
Long Term Acceptance Rate (LTAR)
Receiving septic tank effluent, a treatment level-1 system for chambers requires the infiltrative surface
being at least 4-feet above a limiting layer (43.8, Table 7 -2.4); Maximum hydraulic loading rate for TL1
effluent is 0.6 gal./S.F./day) (Table 10-1) being the long term acceptance rate of the Type 3A receiving
soil.
A(sf) = Qd x L.F.1 x L.F.2.: A = Area;
LTAR LTAR = 0.3 gal/S.F./day for sandy clay loam massive
Qd = flow (gal/day) for OWTS = 270 gpd
L.F.1=0.8 pressure dosed trench application
L.F.2=0.7 Gravelless chambers
STA Sizing: A(sf) = 270 gpd x 0.8 x 0.7 = 504 S.F.
0.3 Gal/S.F./day
OWTS Design and Construction
184 Gas Court, Rifle, Garfield County
SE Job No. 34132 .01
March 10, 2026
Page 4
Number of Quick -4 Infiltrator chambers 4'x3'x12"chambers:
504 S.F = 41 Infiltrator Quick -4 chambers; Use 42 chambers
12 S.F./Chamber
Number of Equivalent Arc-36 chambers 5'x3'x12"chambers:
504 S.F. = 33 chambers; Use 36 chambers
15 S.F./Chamber
Install 42 Quick-4 Infiltrator chambers in 3 trenches 58' long by 3' wide with 14 chamber units per trench
plus two end caps as delineated on the plan. Alternative use 36 Arc-36 chambers in 3 trenches 60.5' long
by 3' wide with 12 chambers units per trench with ends caps. A 4" vertical inspection port riser to be
installed from the molded penetration port on each chamber end cap or each end chamber in the trench.
Effluent Distribution System
The septic tank effluent will be pressure discharged to a common manifold pipe, installed at the head of
the trenches, via a 1.5” transport pipe from the high head pump discharge assembly in a biotube filter vault
set in the second compartment of the 1,000 gallon tank The minimum slope of the transport pipe from the
tank's dosing compartment to the manifold shall be installed at a minimum 2% slope to allow for drain
back to the tank.
The distribution system will be installed for effluent to be equally distributed across the absorptive surface
in each trench via individual custom perforated pressure distribution laterals connected to the manifold
pipe. The distribution laterals will be installed on the infiltrative surface, under the chambers, along the
entire length of each trench. The 5/32 inch orifices will be drilled on 2’ centers oriented upward along the
length of the distribution lateral except for the first and last orifices oriented dowward to allow for
drainage. A ball valve will be installed on the terminal end of each distribution lateral centered below the
4” inspection port, housed in a 10" valve box with lid set 2" above surface grades.
Construction and Inspections
Prior to construction of the permitted system, the engineer should be contacted by the contractor and
construction project manager well in advance to provide adequate time to discuss the system components
with the contractor, answer questions, resolve any conflict issues and schedule inspection site visits based
on construction progress. A pre-OWTS construction meeting and calls are essential and required prior to
installation of the OWTS.
The engineer, prior to excavation shall inspect the staked location, of the proposed treatment/absorption
bed and tank. All septic system components shall be staked in the field for approval by the Engineer prior
to excavation. During initial construction the engineer will evaluate the tank and trench excavations to
confirm design assumptions made, existing conditions and provide recommendations for component
installations. The engineer will provide construction recommendations and make adjustments to the field
layout and sizing if needed with discussion of construction and inspection procedures.
OWTS Design and Construction
184 Gas Court, Rifle, Garfield County
SE Job No. 34132 .01
March 10, 2026
Page 5
As necessary a revised Construction document drawing will be submitted to the County as needed if
changes are required. All installations shall be inspected, surveyed, documented and reported/delineated in
the Certification letter and As-Constructed drawing.
County Regulations require that the Design Engineer of record perform site inspections of the permitted
system during construction and provide “As-Built” documentation of the installed system to the County
after construction is complete. Photo documentation during construction and site system inspections is
required to be performed by the contractor and Engineer. System component installation inspection and
review of photo documentation is required of the exposed system components prior to backfilling. Photo
documentation will be included with the As-Built Record drawing submittal package to finalize the OWTS
permit. Therefore, the Engineer should be contacted as needed and notified of the construction progress
and scheduling to allow time to schedule specific inspection times.
The county environmental health department needs to be contacted at least 48 hours prior to final backfill
of components to provide advanced notice of construction schedule in order to perform a final inspection
of the in place components. The Garfield County Environmental Health contact number is 970-945-6614 x
8106 (main office).
OWTS Operation and Maintenance
All components of the engineered OWTS shall be inspected on a regular basis and be properly maintained.
The responsibility for repair and maintenance of the system will remain with the property Owner. The
owner shall retain the services of qualified personnel to inspect the OWTS and to perform all maintenance
and repairs necessary to ensure that the system is in good operating condition and is in compliance with the
manufacturer’s performance requirements. The operating components of the OWTS shall be inspected by
the engineer within 30 days of being placed into operation and thereafter every six months by the owner or
qualified service provider. In general, for a properly utilized system, septic tanks should be pumped every
3-5 years. The effluent filter should be cleaned every six months and at the time of pumping. Absorption
fields should be maintained with suitable vegetative cover and kept free of root invasive plants. Positive
surface drainage away from the absorption field should be maintained.
If you have any question or need any additional information, please call.
Sincerely,
SOPRIS ENGINEERING, LLC
Paul E. Rutledge Yancy Nichol, PE
Design Engineer Principal
3/10/2026
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Lot 4
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Water Valve &
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O ffi c e
S t e e l P o l e B u il d i n g
(O p e n F r o n t)
280.4'
32.0'
24.5'Spigot
4" PVC's
81.5'
19.5'Rip Rap
Rebar and Plastic Cap
LS No. 31944
Top of Ban k (Ditch)
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Edge of Gravel
Trash
Concrete
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Rock Swale
Rebar and Plastic Cap
LS No. 31944
Rebar and Plastic Cap
LS No. 38200
10.0' Ditch Easement
5.0' Utility Easement
5.0' Utility Easement
24.7'
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Concrete
5.0'
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10.0' SETBACK
305.0
17.0'
58.0'
50.0' DITCH SETBACK
4" PVC EFFLUENT PIPE @ MIN. 1.5 %,
USE SCHD-40 OR SDR-26
4" PVC SEWER PIPE @ 1.5%,
USE SCHD-40 OR SDR-26
INSTALL CHAMBER END CAP ON ALL END CHAMBERS
4" TWO-WAY
CLEANOUT 4" TWO-WAY
CLEANOUT 4" TWO-WAY
CLEANOUT 4" TWO-WAY
CLEANOUT 4" TWO-WAY
CLEANOUT
4''SS
18.0'
48.5'
1.5 ''1 .5''1.5''
1 .5''1.5''1.5''
1.5 ''1.5''1.5''
4''SS 4''SS 4 ''SS 4''SS 4''SS 4''SS 4 ''SS 4''SS 4''SS 4''SS
4''
SS
4''SS
4''SS
INSTALL FULL BODY WYE
(TYP. EACH SEWER PIPE CONNECTION)
INSTALL 4" INSPECTION PORT RISER PIPE EXTEND RISER FROM END
CAP OR CHAMBER INSPECTION PORT FLANGE TO APPROXIMATELY
MIN. 3" BELOW FINISH GRADE W/ PUSH ON CAP & COVER WITH
10" DIA. VALVE BOX SET WITH LID 1" ABOVE FINSH GRADE
(TYP. EACH END TRENCH CHAMBER OR END CAP)
1.5" SCHD-40 TRANSPORT PIPE W/ 2.0' MIN. DEPTH OF BURY.
INSTALL AT MIN. 2% FOR DRAINBACK
1 1/2" PVC SCHD-40 PERFORATED PIPE DISTRIBUTION LATERALS
W/ 3/16-INCH DIA. ORIFICES ON 2' CENTERS ALONG PIPE. (TYP.)
ORIFICES ORIENTED UPWARD BETWEEN FIRST AND LAST.
INSTALL SNAP ON SPRAY SHIELDS ON FIRST & LAST ORIFICES
ORIENTED DOWNWARD.
SOIL TREATMENT AREA FIELD (270 GPD CAPACITY)
USE 42 QUICK-4 CHAMBERS IN 4 TRENCHES WITH 14 CHAMBERS PER ROW FOR A TOTAL
ABSORPTION AREA OF 504 S.F. THE SYSTEM SHALL BE PLUMBED FOR EQUAL PRESSURE
DISTRIBUTION. THE CHAMBERS SHALL BE INSTALLED ON LEVEL GRADE IN EACH TRENCH. THE
BOTTOM OF EACH TRENCH TO BE EXCAVATED TO A MAXIMUM AVERAGE DEPTH OF 24 INCHES
BELOW THE EXISTING SURFACE GRADES, WITHIN THE UPPER HORIZON OF THE NATIVE SANDY
CLAY LOAM SOILS & BACKFILLED WITH A MINIMUM 12-INCHES OF COVER OVER THE CHAMBERS.
INSTALL DEEP BURY, 2-COMPARTMENT 1000-GALLON CONCRETE
SEPTIC TANK W/ REINFORCED LID. INSTALL WITH (1) 24" DIA. BY 60"
DEEP RIBBED PVC RISER & (1) 30" DIA. BY 60" DEEP RIBBED PVC RISER
W/ LIDS AT THE SURFACE. INSTALL ORENCO SIMPLEX EFFLUENT
PUMP ASSEMBLY (ORENCO PF-5005) W/ 2" DISCHARGE ASSEMBLY.
DEPTH TO TOP OF TANK FROM PROPOSED GRADE IS APPROX. 5'.
1.5" PVC DISTRIBUTION MANIFOLD (TYP.)
INSTALL 1.5" FLUSH BALL VALVE ON END OF
EACH DISTRIBUTION LATERAL CENTERED BELOW
THE INSPECTION PORT (TYP. END EA. TRENCH)
5303
5304
5305
5
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EXCAVATION DEPTH 2' MIN.-3' MAX. BELOW SURFACE GRADE WITH
MINIMUM. 12" BACKFILL COVER OVER THE TOP OF CHAMBERS
TOP BACKFILL WITH MIN 3" TOPSOIL & GRADE FIELD SURFACE
AREA APPROXIMATELY 3"-6" ABOVE EXISTING SURFACE GRADES
RECOMMENDED LOCATION OF OWTS PUMP CONTROL BOX INSTALL PUMP CONTROL
BOX IN LINE OF SITE WITH TANK. ELECTRICIAN TO PROVIDE CIRCUITS & WIRES FOR
PUMPS & CONTROLS TO CONTROL PANEL. ELECTRICIAN TO CONFIRM WIRE GAUGE
SIZE & COORDINATE INSTALLATION WITH PUMP SUPPLIER/ INSTALLER.
ET
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EX TERNAL SPLIC E BOX INSTALL W ITH
ELECTRICAL/CONTROL WIRES F ROM CONTROL PANEL
DATE REVISION
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OWTS DESIGN &
CONSTRUCTION
PLAN
1 inch = ft.
( IN FEET )
GRAPHIC SCALE
010 10 10
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1010
MEMBER UTILITIES
FOR THE MARKING OF UNDERGROUND
BEFORE YOU DIG, GRADE, OR EXCAVATE
CALL 2-BUSINESS DAYS IN ADVANCE
Know what's
R
34049.01JOB NO.
DATE:
DESIGNED BY
DRAWN BY
CHECKED BY
PER 03/09/26
WJB 02/23/26
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1.THE OWTS AS SHOWN ON THE PLAN AND THE DETAILS WERE DESIGNED BY SOPRIS ENGINEERING.
2.THE EXISITNG LOT CONDITIONS PER COUNTY GIS DATA BASE, AERIAL MAPPING, LIDAR TOPOGRAPHY.
PLAT INFORMATION SHOWN IS BASED ON A EXISTING CONDITIONS SURVEY BY SOPRIS ENGINEERING
DATED 12/02/2014. PROPOSED LOT CONDITIONS BY SOPRIS ENGINEERING.
3.PROPOSED STRUCTURES BY ALL DRAFT DESIGN SERVICES.
4.PRIMARY OWNER NAME AND ADDRESS: BIG LENNY'S STORAGE RIFLE LLC, 5458 MOUNT VERNON
PARKWAY, ATLANTA, GA 30327
5.SITE ADDRESS: 184 GAS COURT, RIFLE, CO, 81650
6.Legal Summary: SECTION: 18 TOWNSHIP: 6 RANGE: 93 SUBDIVISION: WEST RIFLE INDUSTRIAL PARK
LOT: 4
7.Parcel Number: 217718201004
8. COUNTY SEPTIC PERMIT #:
9.CONTRACTOR: MYRL SERRA, 5mconst.llc@gamil.com
Commercial Design Calculations OWTS
The design flow is calculated as follows for a commercial shop/office facility onsite wastewater
treatment system (OWTS).
The treatment capacity is designed for an equivalent 9 shop/office facilities with an assumed 2
employees each.
From the Regulation 43 usage table :
Minimum population based on 9 offices = 18 staff employees.
Gallons per day per person =15 gal/employee/day,
Max. Design flow (Qd)gallons/day = (# of people) x (avg. flow)gal/person/day.
Design flow Qd = 18*15=270 gpd
Septic Tank Design:
Use a 1000 gallon, two compartment concrete septic tank with an inlet sanitary tee and effluent filter
outlet sanitary tee in the second chamber. Extend new effluent filter handle to within 6" of access
riser lid. The tank shall be installed with ribbed PVC risers and fiber lids or sealed concrete risers and
lids set to approximately 3" above the finish grade surface.
Sub Surface Conditions and Testing:
A subsurface soil investigation and site assessment was performed by Sopris Engineering in on
February 13, 2026. The soils were sampled and characterized by application of the USDA visual/tactile
soil texture method analysis from samples in two profile pits. Two excavated profile pits 1 & 2 were
observed in the East central portion of the site adjacent to the proposed soil treatment area field
location. The soils below 4 to 9 inches of mixed surface fill & gravels consist of medium dense sandy
clay loam with moderate granular to slightly blocky structure with some cobbles and gravels to depths
of 1.5 to 2.0 feet underlain by dense slighty sandy clay loam with less than 5% of total rock content to
the 8 foot depth explored in both pits. The soil appears to be generally consistent across the site. No
evidence of seasonal high ground water, redox conditions or any other limiting conditions were
observed in the profile pits. Groundwater levels are expected to be below 20 feet from the existing
surface grades on the relatively flat terrain. The soils are suitable for a shallow conventional
absorption field consisting of gravelless infiltration chamber units.
Profile Pit-1
The soils below approximately 4 inches of surface gravels consist of moderately dense sandy clay loam
texture fill material with gravels and cobbles that has blocky to granular shape of moderate structural
grade to a depth of 2-feet containing approximately 40% total rock content. Soils below 2 feet
underlying the mixed fill consist of dense slighty sandy clay loam texture soil that has granular to
massive structure of weak structural grade with less than 5% of total rock content to the 8 foot depth
explored. The soils are characterized as a soil type 3A Sandy clay loam. No free water or limiting
condition was encountered in the pit excavation.
Profile Pit-2
The soils below approximately 3 inches of surface gravels consist of moderately dense sandy clay loam
texture fill material with gravels and cobbles that has blocky to granular shape of moderate structural
grade to a depth of 1-foot containing approximately 40% total rock content. Soils below 1.5 feet
underlying the mixed fill consist of dense slighty sandy clay loam texture soil that has granular to
massive structure of weak structural grade with less than 5% of total rock content to the 8 foot depth
explored. The soils are characterized as a soil type 3A Sandy clay loam.No free water or limiting
condition was encountered in the pit excavation.
The native soils sampled from 2-4 feet below the surface, in both profile pits, are characterized as a
soil type 3A soil type consisting of slighty sandy clay loam texture soil with granular to massive
structure of weak structural grade. The tan to grayish sandy clay loam soil tactile test ribbons were 1
¾-inch long. Soil type 3A has an effective loading rate for conventional soil treatment of 0.30
gal/S.F./day for a level 1 conventional treatment system. The equivalent percolation rate of these
soils is assumed to be 61-75 minutes per inch.
Additional observations will be performed during construction to inspect the shallow trench chamber
trench excavations, absorptive surface preparation in the soil treatment area and provide guidance
for installations of the specified materials in the in-situ native soils. If any adjustments to design or
installation recommendations are necessary, notice will be made to County EHD and applicable
revisions to design/construction plans and report will be submitted. All conditions and installations
will be included in the As-Constructed documentation.
Chamber Treatment Unit/ Absorption System Design
The treatment/absorption trenches are designed based on utilizing the effective Long Term
Acceptance Rate (LTAR) for native soils and the application of appropriate loading factors for a
treatment level-1 system utilizing pressure dosed chamber trenches. The new treatment system will
consist of pressure dosed chamber trenches with custom perforated distribution laterals, in
accordance with Regulation 43 sections (43.10(C), 43.13.E.1.d, Table 10-2 and Table 10-3 as approved
by CDPHE for this technology.
Long Term Acceptance Rate (LTAR)
Receiving septic tank effluent, a treatment level-1 system for chambers requires the infiltrative
surface being at least 4-feet above a limiting layer (43.8, Table 7-2.4); Maximum hydraulic loading rate
for TL1 effluent is 0.3 gal./S.F./day) (Table 10-1) being the long term acceptance rate of the Type 3A
receiving soil.
A(sf) = Qd x L.F.1 x L.F.2 .: A = Area;
LTAR LTAR = 0.3 gal/S.F./day for sandy clay loam massive
Qd = flow (gal/day) for OWTS = 270 gpd
L.F.1=0.8 pressure dosed trench application
L.F.2=0.7 Gravelless chambers
STA Sizing: A(sf) = 270 gpd x 0.8 x 0.7 = 504 S.F.
0.3 Gal/S.F./day
Number of Quick-4 Infiltrator chambers 4'x3'x12"chambers:
504 S.F = 41 Infiltrator Quick-4 chambers; Use 42 chambers
12 S.F./Chamber
Number of Equivalent Arc-36 chambers 5'x3'x12"chambers:
504 S.F. = 33 chambers; Use 36 chambers
15 S.F./Chamber
Install 42 Quick-4 Infiltrator chambers in 3 trenches 58' long by 3' wide with 14 chamber units per
trench plus two end caps as delineated on the plan. Alternative use 36 Arc-36 chambers in 3 trenches
60.5' long by 3' wide with 12 chambers units per trench with ends caps. A 4" vertical inspection port
riser to be installed from the molded penetration port on each chamber end cap or each end chamber
in the trench.
YTN
03-10-26
YTN
TYPICAL YARD LANDSCAPED SURFACE
OR AGGREGATE PAVED SURFACE
6" MIN.
4" MIN.
4"
N.T.S.
4"NATIVE SCREENED
EXCAVATED MATERIAL
COMPACTED TO 90%
STANDARD PROCTOR
NOTE:
ALL CHAMBERS IN EACH TRENCH MUST BE INSTALLED ON LEVEL GRADE.
MAXIMUM DEPTH OF TRENCHES NOT TO EXCEED 36" BELOW PROPOSED
SURFACE GRADES. END CAPS TO BE INSTALLED ON EACH END CHAMBER.
INSTALL INDIVIDUAL CUSTOM PERFORATED DISTRIBUTION LATERALS ON TOP OF
THE NATIVE SOIL ABSORPTIVE SURFACE WITH ORIFICES ORIENTED UPWARD
EXCEPT THE FIRST AND LAST ORIFICES TO BE ORIENTED DOWNWARD. CONNECT
LATERALS AT THE HEAD OF EACH CHAMBER TRENCH FROM THE SPECIFIED
MANIFOLD ARRANGEMENT AS SHOWN ON THE PLAN. INSTALL A 4" VERTICAL
INSPECTION PORT RISER FROM THE MOLDED PENETRATION PORT ON EACH
CHAMBER END CAP OR EACH END CHAMBER IN THE TRENCH. INSTALL A BALL
VALVE AT THE TERMINAL END OF THE DISTRIBUTION LATERAL ACCESSIBLE FROM
THE INSPECTION PORT TO ALLOW FLUSHING OF THE PIPE.
NATIVE SOIL BACKFILL
SCARIFY BOTTOM SURFACE W/
FINAL PASS OF BUCKET TEETH
QUICK-4 INFILTRATOR
OR EQUAL ARC-36 CHAMBER
N.T.S.
EXISTING GRADE
FILTER FABRIC
NATIVE SOIL BACKFILL
SCREENED OF +3" ROCK
UNDISTURBED EARTH
SANDY SILT LOAM SOIL
CUSTOM PERFORATED DISTRIBUTION LATERAL
SECURE PIPE WITH PUSH IN STAPLES
SEED AND MULCH FINISH SURFACE
MAINTAIN SUITABLE VEGETATIVE COVER
CROWN FIELD TRENCH TO
DIVERT SURFACE WATER
1.5" SCHD-40 PVC
DISTRIBUTION MANIFOLD
CHAMBER UNIT INFILTRATOR
QUICK-4 OR ABS ARC-36 BIO DIFFUSER
SET 4" INSPECTION PORT RISER PIPE ON END CAP OR
END CHAMBER PRE FORMED PENETRATION SECURE
WITH SHORT SCREWS THROUGH FLANGE INTO PIPE 6" VALVE BOX
4" INSPECTION PORT RISER
4" PUSH ON CAP
6" VALVE BOX
INFILTRATOR QUICK-4 END CAP
4" INSPECTION PORT RISER
1.ALL MATERIALS AND INSTALLATION SHALL CONFORM TO STATE AND COUNTY ONSITE
WASTEWATER TREATMENT SYSTEM (OWTS) REGULATIONS.
2.IT IS THE RESPONSIBILITY OF THE CONTRACTOR TO CONTACT ALL UTILITY COMPANIES FOR
FIELD LOCATIONS OF UTILITIES PRIOR TO CONSTRUCTION AND EXCAVATION.
3.ALL SEWER LINES TO BE SDR-35 OR SCHEDULE 40 P.V.C. PIPE UNLESS NOTED OTHERWISE.
4.INSTALL A TWO-WAY CLEAN OUT ON THE SERVICE LINE FROM THE STRUCTURE AND AN
ADDITIONAL CLEANOUT WITHIN 100' SECTION OF EFFLUENT DISCHARGE PIPE .
5.THE SEPTIC TANK SHALL BE INSTALLED LEVEL ON COMPACTED EARTH. INSTALL WATERTIGHT
RISERS AS NECESSARY TO BRING ALL REQUIRED ACCESS POINTS TO THE FINISHED SURFACE
GRADE. BACKFILL WITH SUITABLE NATIVE SOIL FREE OF BOULDER AND ROCK IN EXCESS OF 3"
DIAMETER.
6.A SANITARY BAFFLE TEE IS REQUIRED ON THE SEPTIC TANK INLET AND OUTLET. INSTALL THE
INLET AND OUTLET TEES PLUMB AND IN A POSITION TO ALLOW EASY INSPECTION AND
MAINTENANCE OF TANK FROM THE TANK RISERS.
7.INSTALL A 4" EFFLUENT FILTER ON THE 4" OUTLET TEE OF THE SEPTIC TANK. THE FILTER
SHOULD BE INSPECTED EVERY SIX MONTHS. THE EFFLUENT FILTER SHALL BE MAINTAINED AND
CLEANED WHEN THE TANK IS PERIODICALLY PUMPED OR AS NECESSARY. INSTALL A SUITABLE
EXTENSION ON THE FILTER WITH A HANDLE TO BE WITHIN 6" BELOW THE ACCESS LID.
8.THE CONTRACTOR SHALL ENSURE THAT THE SEWER LINES, SEPTIC TANK AND RISERS ARE
WATERTIGHT. ALL PLUMBING FIXTURES AND OWTS COMPONENTS SHALL BE INSTALLED AND
MAINTAINED TO AVOID SURFACE OR GROUNDWATER FROM ENTERING THE SYSTEM AND TO
PREVENT LEAKAGE FROM THE SYSTEM.
9.THE DIMENSIONS AND NOTES SHOWN ON THE PLAN INDICATE MINIMUM AREA, LENGTH,
WIDTHS AND SEPARATION DISTANCES FOR THE TRENCHES, BED OR MOUNDED ABSORPTION
FIELD.
10.THE INFILTRATING CHAMBERS SHALL BE PLACED LEVEL IN THE TRENCH ON THE NATIVE SOIL
SURFACE. THE BOTTOM SURFACE OF THE EXCAVATION SHALL BE SCARIFIED PRIOR TO
PLACEMENT OF CHAMBERS OR SELECT SAND LAYER. IF EXCESSIVE LARGE COBBLES OR
BOULDERS ARE ENCOUNTERED IN ANY PART OF THE EXCAVATION WITHIN 6" OF THE SURFACE
GRADE, OVER EXCAVATE AND BACKFILL WITH SAND LEVEL WITH THE ABSORPTIVE SURFACE.
11.THE LEACHING CHAMBERS SHALL BE INSTALLED LEVEL. END CAPS SHALL BE INSTALLED ON THE
END CHAMBERS IN EACH ROW. VERTICAL INSPECTION PORTS SHALL BE INSTALLED FROM THE
PRE MARKED HOLE PENETRATION ON THE TOP OF EACH END CHAMBER OR END CAP. (TYP.
BOTH ENDS OF EACH ROW) THE PORTS MAY HAVE THREADED CAPS AT GRADE OR BE HOUSED
IN A 6" VALVE BOX.
12.THE TOP OF THE PLACED CHAMBERS SHALL BE COVERED WITH FILTER FABRIC AND BACKFILLED
WITH A MINIMUM COVER OF 10 INCHES NOT TO EXCEED 24 INCHES.
13.THE BEDS WILL BE BACKFILLED WITH EXCAVATED MATERIAL VOID OF ROCKS, THE BACKFILL
MATERIAL SHALL NOT EXCEED 2 1/2" DIAMETER AND SHALL BE PLACED TO AT LEAST 3 INCHES
ABOVE THE TOP OF THE BEDS. A MINIMUM 3" DEPTH OF TOPSOIL IS TO BE PLACED ABOVE THE
BACKFILL TO THE SURFACE & RE VEGETATED.
14.INSTALLATION OF LEACHING BEDS SHALL BE IN CONFORMANCE WITH THE MANUFACTURERS
INSTALLATION INSTRUCTIONS.
15.THE ABSORPTION TRENCHES OR BEDS MUST BE GENERALLY MARKED AT THE END OF EACH
CHAMBER ROW WITH INSPECTION PORTS. THE FIELDS MUST BE PROTECTED FROM VEHICULAR
AND LIVESTOCK TRAFFIC.
16.THE ABSORPTION FIELD SURFACES MUST BE SLOPED OR SLIGHTLY MOUNDED TO DIVERT
SURFACE DRAINAGE AWAY FROM THE FIELD.
17.THE ABSORPTION FIELD SHALL BE INSTALLED PER THE REQUIRED SETBACK DISTANCES:
10 FEET FROM ANY PROPERTY LINE.
25 FEET FROM ANY POTABLE WATER SUPPLY LINE.
20 FEET FROM ANY OCCUPIED DWELLING WITH CRAWL SPACE .
100 FEET FROM ANY WELL, SPRING OR CISTERN.
50 FEET FROM ANY STREAM OR WATER COURSE.
1.ADDITIONAL GEOTECHNICAL EVALUATIONS AND INSPECTIONS BY THE ENGINEER SHOULD BE
PERFORMED DURING INITIAL STAGES OF CONSTRUCTION TO VERIFY SOIL CONDITIONS AND OWTS
DESIGN.
2.THE EVALUATIONS AND INSPECTIONS MAY RESULT IN MODIFICATIONS TO THE DESIGN THAT MAY
INCLUDE FIELD LOCATION ADJUSTMENTS AND REGRADING IN SELECT AREAS IF NEEDED. SUFFICIENT
NOTICE TO THE ENGINEER BY THE PROJECT MANAGER/CONTRACTOR NEEDS TO BE MADE IN ORDER
TO SCHEDULE THE SITE INSPECTIONS.
3.PRIOR TO CONSTRUCTION OF THE PERMITTED SYSTEM THE ENGINEER SHOULD BE CONTACTED BY
THE PROJECT MANAGER/CONTRACTOR WELL IN ADVANCE TO PROVIDE ADEQUATE TIME TO DISCUSS
THE SYSTEM COMPONENTS WITH THE CONTRACTOR, ANSWER QUESTIONS, RESOLVE ANY CONFLICT
ISSUES AND SCHEDULE INSPECTION SITE VISITS BASED ON CONSTRUCTION PROGRESS.
4.COUNTY REGULATIONS REQUIRE THAT THE DESIGN ENGINEERS OF RECORD PERFORM SITE
INSPECTIONS OF THE PERMITTED SYSTEM DURING CONSTRUCTION AND PROVIDE
"AS-CONSTRUCTED" DOCUMENTATION OF THE INSTALLED SYSTEM TO THE COUNTY AFTER
CONSTRUCTION IS COMPLETE. THE ENGINEER SHOULD BE CONTACTED AND NOTIFIED OF THE
CONSTRUCTION SCHEDULE.
5.THE COUNTY ENVIRONMENTAL HEALTH DEPARTMENT SHOULD BE CONTACTED AT LEAST 48 HOURS
PRIOR TO FINAL BACKFILL OF COMPONENTS TO PROVIDE ADVANCED NOTICE OF CONSTRUCTION
SCHEDULE IN ORDER TO PERFORM A FINAL INSPECTION OF THE IN PLACE COMPONENTS. THE
GARFIELD COUNTY ENVIRONMENTAL HEALTH CONTACT NUMBER IS: 970-945-6614 X 8106 (MAIN
OFFICE)
6.OUR DESIGN AND RECOMMENDATIONS ARE BASED OUR SITE ASSESSMENT, SOIL EVALUATION AND
UPON INFORMATION SUPPLIED TO US BY OTHERS. IF SUBSURFACE OR SITE CONDITIONS ARE FOUND
TO BE DIFFERENT FROM CONDITIONS ASSUMED OR INDICATED, WE SHOULD BE NOTIFIED TO
EVALUATE ANY EFFECT ON THE PROPOSED OWTS. IF THE COUNTY REQUESTS CHANGES OR
MODIFICATIONS TO THIS DESIGN, WE SHOULD BE CONTACTED TO EVALUATE AND RESPOND TO THE
REQUEST.
7.CONTRACTOR SHOULD REVIEW ANY CONDITIONS ON THE ISSUED PERMIT AND COORDINATE WITH
THE ENGINEER REGARDING CONSTRUCTION OF THE SYSTEM. THE CONTRACTOR AND/OR SYSTEM
INSTALLAR SHOULD PHOTO DOCUMENT ALL PHASES OF OWTS CONSTRUCTION AND INSTALLATION
OF COMPONENTS.
8.IF YOU HAVE ANY QUESTION OR NEED ANY ADDITIONAL INFORMATION, PLEASE CALL PAUL
RUTLEDGE AT SOPRIS ENGINEERING, 704 0311.
1.FILTERED EFFLUENT WILL DISCHARGE TO THE TRENCH LATERALS VIA A SIMPLEX HIGH HEAD
PUMP BIOTUBE DISCHARGE ASSEMBLY TO A COMMON MANIFOLD AT THE HEAD OF THE STA
BED OR TRENCHES THAT CONNECTS TO THE DISTRIBUTION LATERAL ROWS.
2.THE DISTRIBUTION SYSTEM WILL BE INSTALLED TO ALLOW FOR EFFLUENT TO BE EQUALLY
DISTRIBUTED ACROSS THE ABSORPTION SURFACE IN EACH TRENCH VIA INDIVIDUAL CUSTOM
PERFORATED FULL PRESSURE DISTRIBUTION LATERALS CONNECTED TO THE MANIFOLD PIPE AT
THE HEAD OF THE BEDS OR TRENCHES INSTALLED ON TOP OF THE SAND MEDIA SURFACE
ALONG THE ENTIRE LENGTH OF THE INDIVIDUAL LATERAL ROWS. A BALL VALVE WILL BE
INSTALLED ON THE TERMINAL END OF EACH DISTRIBUTION LATERAL CENTERED BELOW AND
HOUSED IN A VALVE BOX WITH LID SET 2" ABOVE SURFACE GRADES.
3.THE MINIMUM SLOPE OF THE TRANSPORT PIPE FROM THE TANK'S DOSING COMPARTMENT TO
THE MANIFOLD SHALL BE INSTALLED AT A MINIMUM 2.5% UPWARD SLOPE TO ALLOW FOR
DRAINBACK TO THE PUMP VAULT.
1.AN ORENCO SYSTEMS CONTROL PANELS SHALL BE INSTALLED BY A ELECTRICIAN IN
COORDINATION WITH THE CONTRACTOR AND THE TREATMENT SYSTEM SUPPLIER/SERVICE
PROVIDER. ELECTRICIAN TO PROVIDE ELECTRIC SERVICE FOR SPECIFIED VOLTAGE RATING OF
PUMP(S) AND CONTROLS. THE POWER SUPPLY FOR THE PUMP(S) AND CONTROLS SHALL
CONSIST OF A 20 AMP CIRCUIT FOR THE PUMP AND 10 AMP CIRCUIT FOR CONTROLS.
CONTROL PANEL PANEL TO BE INSTALLED BY ELECTRICIAN IN LINE OF SITE WITH TANK AND/OR
PUMP BASINS.
2.THE ELECTRICIAN SHALL INSTALL ELECTRICAL SUPPLY WIRE IN CONDUIT FROM A ELECTRICAL
SERVICE CIRCUIT BREAKER BOX TO THE REMOTE SUPPORT MOUNTED ORENCO CONTROL
PANEL LOCATED IN LINE OF SITE ADJACENT TO THE DOSING COMPARTMENT TANK RISER.
3.ELECTRICIAN TO WIRE ELECTRIC SUPPLY INTO CONTROL PANEL CIRCUITS AND INSTALL
CONDUIT FOR PUMP AND CONTROL WIRES OUT OF CONTROL PANEL AND IN TO THE EXTERNAL
SPLICE BOX MOUNTED ON THE EXTERIOR OF THE PUMP BASIN TANK RISER.
4.THE SYSTEM QUALIFIED INSTALLER SHALL INSTALL ELECTRICAL WIRES THROUGH THE
INSTALLED CONDUITS FROM THE CONTROL PANEL TO THE EFFLUENT PUMP ASSEMBLY'S (IF
APPLICABLE) EXTERNAL SPLICE BOXES ON THE RESPECTIVE TANK ACCESS RISER. INSTALL
COLOR CODED OR LABELED WIRES PER CONTROL PANEL DIAGRAM. INSTALL ALL WIRES FOR
PUMP(S) AND CONTROLS WITH CONDUIT SEAL AT THE SPLICE BOX. ELECTRICIAN TO
COORDINATE W/ SYSTEM INSTALLER. FOR PUMP AND CONTROL INSTALLATION. INSTALLATION
CONSULTATION BY SOPRIS ENGINEERING.
DEEP BURY TANK
7" REINFORCED
TANK LID
REQUIRE MANUFACTURER
DEEP BURY TANK
REINFORCEMENT
03/10/26
3/10/2026