HomeMy WebLinkAbout2.16 Natural and Geologic Hazards Report
NATURAL AND GEOLOGIC HAZARDS
ASSESSMENT REPORT
OXY POND 10 N/S
PRODUCED WATER POND
SE ¼, SW 1/4 SECTION 5, T7S, R97W, 6TH P.M.
GARFIELD COUNTY, COLORADO
PREPARED FOR
OXY USA WTP LP
760 HORIZON DRIVE, SUITE 101
GRAND JUNCTION, COLORADO 81506
PREPARED BY
OLSSON ASSOCIATES
4690 TABLE MOUNTAIN DRIVE, SUITE 200
GOLDEN, COLORADO 80403
MARCH 2014
PROJECT NO. 013-0656
Geologic Hazard Report Olsson Associates
OXY Pond 10 Golden, Colorado
Garfield County, CO March 2014
Project #013-0656
i
TABLE OF CONTENTS
TABLE OF CONTENTS ................................................................................................................. i
FIGURES ....................................................................................................................................... i
1.0 EXECUTIVE SUMMARY ..................................................................................................... 1
2.0 GENERAL SITE LOCATION AND BACKGROUND ............................................................ 2
2.1 Project and Site Description ............................................................................................ 2
2.2 Structural Geology ........................................................................................................... 2
2.3 Site Bedrock Geology ...................................................................................................... 3
2.4 Site Surficial Geology and Soil ........................................................................................ 3
2.5 Hydrologic Setting ............................................................................................................ 4
2.6 Aquifers ............................................................................................................................ 4
3.0 NATURAL AND GEOLOGIC HAZARD ASSESSMENT ...................................................... 5
3.1 Utilities ............................................................................................................................. 5
3.2 Avalanche Hazard Area ................................................................................................... 5
3.3 Landslide Areas or Potential Landslide Hazard Areas .................................................... 5
3.4 Rockfall Areas .................................................................................................................. 5
3.5 Alluvial Fan Hazard Areas ............................................................................................... 6
3.6 Unstable or Potentially Unstable Slopes .......................................................................... 6
3.7 Corrosive or Expansive Soils and Rock ........................................................................... 6
3.8 Mudflow and Debris Fan Areas ....................................................................................... 7
3.9 Development Over Faults ................................................................................................ 7
3.10 Flood Prone Areas ........................................................................................................... 8
3.11 Collapsible Soils .............................................................................................................. 8
3.12 Mining Activity .................................................................................................................. 8
3.13 Radioactivity .................................................................................................................... 8
4.0 CONCLUSIONS AND RECOMMENDATIONS .................................................................. 10
5.0 NATURAL AND GEOLOGIC HAZARD REPORT BACKGROUND ................................... 11
6.0 PROFESSIONAL GEOLOGIST CERTIFICATION ............................................................ 13
7.0 REFERENCES ................................................................................................................... 14
FIGURES
List of Figures
Location Map
Topographic Map
Geology Map
Soils Map
Surface Water Map
Floodplain Map
Geologic Hazard Report Olsson Associates
OXY Pond 10 Golden, Colorado
Garfield County, CO March 2014
Project #013-0656
1
1.0 EXECUTIVE SUMMARY
Olsson Associates (Olsson) was contracted by OXY USA WTP LP (Oxy) to assess natural and
geologic hazards potentially present in the area of the proposed Pond 10 in Garfield County,
Colorado. The site will be used to store oilfield equipment including pipe, fittings, valves, and
tanks. No occupied structures are planned to be constructed onsite. The site lies at an
elevation greater than 5,800 feet above mean sea level (amsl). The Location Map shows the
general location of the Pond 10.
The purpose of this report is to identify geologic conditions that may pose hazards to a land
development project in order that appropriate mitigation or avoidance techniques may be
implemented as described in the Garfield County LUDC. According to the Garfield County
LUDC, Section 7-207, the types of natural and geologic hazards identified pertain to the
following:
A. Utilities;
B. Development in Avalanche Hazard Areas;
C. Development in Landslide Hazard Areas;
D. Development in Rock Fall Hazard Areas;
E. Development in Alluvial Fan Hazard Areas;
F. Slope Development;
G. Development on Corrosive or Expansive Soils and Rock;
H. Development in Mudflow Areas; and
I. Development Over Faults.
This report presents Olsson findings following an evaluation of these and other geologic
hazards potentially affecting the site and proposed development. The site was found to be
suitable for the proposed development, but is in an area of steep slopes within Conn Creek
canyon. Although the area has not been mapped for geologic hazards, there is a potential for
unstable or potentially unstable slopes and associated rock fall and slides to impact the
development. Steep slopes are found in areas to the northeast and east of the Pond 10 Site.
There is an intermittent drainage on the north side of the Pond 10 Site that drains to Conn
Creek. Rockfall and slide mitigation should be designed by a qualified and licensed professional
engineer in accordance with Section 4-203 and Section 7-108 of the LUDC. A qualified licensed
professional engineer should make the final determination on how to best mitigate these risks.
A diversion ditch has been constructed around the perimeter of the produced water pond. A
stormwater retention pond is proposed on the southeast corner of the site. A low hill located on
the east side of the site is proposed to be graded with a 2:1 slope. This hill separates the Pond
10 Site from the drainage swale and the steep slopes to the east and northeast of the Site. This
report should be read in its entirety, including but not limited to the conclusions and
recommendations in section 4.0.
Geologic Hazard Report Olsson Associates
OXY Pond 10 Golden, Colorado
Garfield County, CO March 2014
Project #013-0656
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2.0 GENERAL SITE LOCATION AND BACKGROUND
Oxy contracted Olsson Associates (Olsson) to conduct a natural and geologic hazards
assessment as part of the proposed development of the Pond 10 Site. The following sections
provide information about the proposed development and the site geologic setting. The
Topographic Map shows the location of the Pond 10 Site.
2.1 Project and Site Description
The Oxy Pond 10 Site will be used as a centralized exploration and production (E&P) waste
management facility per the Colorado Oil and Gas Conservation Commission (COGCC) Rule
908. The site consists of adjacent ponds that are being permitted as one facility for the storage
of produced water. The Pond 10 Site is located near Conn Creek north of the town of DeBeque
in western Garfield County, Colorado. The site is located in the southeast quarter of the
southwest quarter of Section 5, Township 7 South, Range 97 West, of the 6th Principal Meridian.
2.2 Structural Geology
The proposed Pond 10 Site is located in the south-eastern part of the Piceance Basin; an
irregularly-shaped elongated basin formed by tectonic forces associated with the Laramide
orogeny. Tectonic forces downwarped the earth’s crust to form the Piceance Basin as a result
of the uplift of the surrounding Colorado Rocky Mountains and the Colorado Plateau. The site is
located on the Roan Plateau in the proximity of Red Pinnacle. The site is located on the Red
Pinnacle 7.5-minute topographic map.
The Piceance Basin is the major structural geologic feature in the region. It is bound to the east
by the Grand Hogback monocline, the White River Uplift to the northeast, the Gunnison Uplift to
the south, the Uncompahgre Uplift to the southwest, the Douglas Creek Arch to the west-
northwest, and the axial basin uplift to the north (Grout and Verbeek, 1992). The central Roan
Plateau area covers an area of approximately 230 square miles in Garfield and Rio Blanco
Counties in the south-central part of the Piceance Basin in northwestern Colorado.
Sedimentary rocks in the southwestern Piceance Basin gently dip to the north - northeast
except where this regional dip is interrupted by low-amplitude folds. Numerous small sub-
parallel northwest trending folds have been identified in the Green River Formation within the
basin. The project site is located approximately 3 miles to the south of the Crystal Creek
anticline. The Pond 10 storage Site is located near the axis of the Clear Creek syncline which
passes through the southwest quarter of Section 5. The Crystal Creek anticline and the Clear
Creek syncline are a northwest trending fold system that start near the Colorado River and
extend for a distance of approximately 30 miles. The Crystal Creek anticline forms the
southeastern element of an anticlinal fold that trends across the southwestern part of the
Piceance Basin. The Clear Creek syncline is a parallel fold located to the southwest (Hail,
1992).
Geologic Hazard Report Olsson Associates
OXY Pond 10 Golden, Colorado
Garfield County, CO March 2014
Project #013-0656
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A fault is a fracture in rock along which movement has occurred. No significant faulting is
known in the project area, but some jointing may occur in proximity to the folds. Three narrow
down-dropped block valleys, known as grabens, and bound by normal faults are present along a
northwest trending fracture zone in the northern part of the area. The maximum stratigraphic
displacement on these faults does not exceed 120 feet and most displacements are
considerably less. Small northwest striking faults between the graben in the central part of
Township 4 South, Range 97 West and the graben in southwestern part of Township 4 South,
Range 96 West suggest that the grabens lie along a single fracture zone that extends for a total
distance of approximately nine miles (Hail, 1992).
2.3 Site Bedrock Geology
As shown on the attached Geology Map, the bedrock underlying the proposed Site is
composed of the lower part of the Green River Formation. These units are composed of
claystone, siltstone, shale, and marlstone. The Roan Cliffs expose hundreds of feet of the
Green River Formation. The Green River Formation has been subdivided into four members
which include the basal Douglas Creek member, Garden Gulch member, the Anvil Points
member, and the Parachute Creek Member. Underlying the Green River Formation are the
early Eocene and Paleocene Wasatch and Fort Union Formations as well as the Cretaceous
Mesaverde Group (Robson and Banta, 1995).
The lower part of the Green River Formation is comprised of the Douglas Creek and Garden
Gulch members and is considered a confining unit that separates the overlying Lower Piceance
Basin aquifer in the Anvil Points Member from the underlying Fort Union and Mesaverde
aquifer. A thin layer of modern alluvium associated with the Conn Creek drainage covers the
bedrock near the site.
2.4 Site Surficial Geology and Soil
The proposed Pond 10 Site is located on Pleistocene and Holocene deposits that include
alluvium, alluvial fans, talus, and slope wash. These surficial deposits consisting of silt, sand,
and clay were derived primarily from the weathering of the Green River Formation and .
Erosional processes dominate in this setting, as the weathered soils are drawn toward the
surrounding canyons by precipitation, snowmelt, and wind.
The Soils Map shows the soil types beneath the site and surrounding properties. The proposed
Site is underlain by soils mapped by the U.S. Natural Resources Conservation Service as the
Happle very channery sandy loam, which is a deep, well-drained soil found on alluvial fans
occupying 3 percent to 12 percent slopes, at elevations of 5,200 to 6,000 feet. It is formed in
alluvium derived dominantly from the Tertiary Green River Formation. The surface layer is
typically light gray very channery sandy loam in the upper 7 inches and grades into a very pale
brown. Permeability is moderate, and the available water capacity is low in the Happle soil.
The effective rooting depth is 60 inches or more. Runoff is slow, and the hazard of water
erosion is severe.
Geologic Hazard Report Olsson Associates
OXY Pond 10 Golden, Colorado
Garfield County, CO March 2014
Project #013-0656
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The Happle very channery sandy loam has a pH range of 7.4 to 8.4 standard units. According
to the Soil Survey of the Douglas-Plateau Area, Colorado these soils are somewhat limited for
local roads and streets due to frost action, are somewhat limited for shallow excavations due to
cutbank caves. Small commercial buildings are limited due to slope; however, small dwellings
with or without basements are not limited.
2.5 Hydrologic Setting
Surface water features within two miles of the project site include Conn Creek, approximately
450 feet to the west. The confluence of Conn Creek and Gilman Gulch is located approximately
one mile to the northwest, and the confluence of Conn Creek with East Fork Canyon is located
approximately one mile south. The proposed Pond 10 Site will be located adjacent to an
existing facility, Coyote Pond/10 South, COGCC facility ID #291946. There is a chute with an
intermittent drainage located to the north of the facility.
The site is shown on the USGS 1:24,000 topographic map (Red Pinnacle Quadrangle). Conn
Creek has perennial flow, although no flow records are available to determine the flow
conditions in these drainages. Evaluation of aerial imagery in Google Earth taken in August
2011 shows very little to no flow in Conn Creek near the proposed storage facility. A stock pond
is located approximately 330 feet to the southwest of the site. The Surface Water Map shows
the site in proximity to Conn Creek and the stock pond.
2.6 Aquifers
The Pond 10 Site is located on a low alluvial terrace above Conn Creek. Shallow groundwater
is contained within the modern alluvium and is directly in communication with surface water in
Conn Creek. The Uinta – Animas aquifer in the Piceance Basin consisting of the Uinta
Formation and the Parachute Creek Member of the Green River Formation lie topographically
and stratigraphically above the Site and therefore would not be affected by the site. The
bedrock in the area of the Pond 10 Site consists of the lower part of the Green River Formation
and the Wasatch Formation which form a confining unit
Groundwater is expected to lie at depths more than 40 feet below ground surface based on area
water well records from the Colorado Division of Water Resources for nearby wells. This
groundwater is contained within alluvium and terrace deposits and is in communication with the
flow in Conn Creek. A spring is shown on the Red Pinnacle topographic map in the northern
part of Section 5.
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
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3.0 NATURAL AND GEOLOGIC HAZARD ASSESSMENT
The following sections present the assessment of geologic hazards in the vicinity of the
proposed Pond 10 Site. This site was previously developed for use as a produced water storage
facility.
3.1 Utilities
Installation of buried utilities may be affected by the relatively shallow depth to sedimentary
bedrock and fractures within the bedrock substrate. The Pond 10 Site is to be used for the
storage of produced water as a Centralized E&P Waste Management Site and has been
engineered and designed to have a double-liner system. An access road that is approximately
750 feet will be constructed around the perimeter of the produced water storage facility.
3.2 Avalanche Hazard Area
The site is not located in a known avalanche hazard area. Winters are cold in the mountainous
areas of Garfield County and valleys are colder than the lower pars of adjacent mountains due
to cold air drainage. Average seasonal snowfall in Garfield County is 50 inches. The greatest
snow depth at any one time during the period of record from 1951 to 1974 was 29 inches
recorded at Rifle, Colorado.
The Pond 10 Site and the access road are not expected to be within an avalanche prone area.
Therefore, avalanches are not expected to pose a hazard to the proposed development.
3.3 Landslide Areas or Potential Landslide Hazard Areas
The site and access road are not located within an area that has been mapped with landslide
hazard areas. It is on an alluvial terrace in an area surrounded by steep slopes composed of
the Green River Formation. It appears that there are slide areas located to the north and south
of the Pond 10 Site based on site photographs and aerial photography. Debris fans appear at
the base of the slopes and appear to have mature vegetation covering them. It is possible for
future slides and rock fall to occur in this area.
3.4 Rockfall Areas
The Site and access road are in an area of rockfall or potential for rockfall. Rockfall areas are
present to the northeast and east-southeast in the steep precipices as shown on the adjacent
land use map and the parcel location map. The site is located in between two chutes where
rocks have slid down the steep sides of the canyon in the past, and therefore have the potential
for future rockfalls.
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
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The Site will be constructed with a buffer area around the perimeter to protect it in the event of
rock falls. According to draft working copy plans prepared by DR Griffin & Associates, of Rock
Springs, Wyoming, dated 03/06/2014 the pond will be located approximately 25 feet from the
toe of the slope and a low hill to the east of the Site will have a maximum height of 5 feet to 10
feet above the base of the swale, and 35 feet above the base of the Pond 10 pad. The swale
will vary in width from 12 feet to 2 feet, and in depth from one foot to five feet. The access road
coming into the south side of the Site is at the toe of a historic rock slide. A qualified licensed
professional engineer in accordance with Section 4-203 and 7-108 of the LUDC should make
the final determination on how to best mitigate rockfall risks.
3.5 Alluvial Fan Hazard Areas
The Site is not located in a mapped alluvial fan hazard area. Alluvial fans are present at the
mouths of the canyons where they discharge onto the Colorado River floodplain.
3.6 Unstable or Potentially Unstable Slopes
Slopes to the north and east are potentially unstable. The pond has an access road and water
diversion around the uphill side and the sides of the pond are built up with gabions. These
engineering controls are expected to mitigate rockfall, slides, or debris flows.
Development of areas with moderate slope hazard consisting of debris fans and minor rockfall
areas should include a detailed geologic investigation to accompany an engineering study
including test drilling, simple strength tests, groundwater evaluation and stability analysis.
Mitigation is usually possible, but could be expensive and may involve large scale construction
work.
Much of the area immediately north and west of the towns of DeBeque and Parachute is
considered to have major slope hazards. An area of major hazard, such as active landslide
area, may include more investigation which includes geologic study, intensive drilling, and
sophisticated strength testing stability analyses, and monitoring of soil, rock, and groundwater
conditions during the engineering and design phase of the project. Mitigation may be possible,
but also may be expensive, may require special siting, and will involve some risk. Avoidance
may be recommended for projects of lower economic value (Garfield County, Slope Hazard
Study 2002).
3.7 Corrosive or Expansive Soils and Rock
The Pond 10 Site and access road are not located in an area known to have expansive soil or
rock types, although building site development for local roads and streets is somewhat limited
due to frost action, and shallow excavations are somewhat limited due to cutbank caving.
Sedimentary rock containing high salt content, such as bicarbonate, chloride or sulfate, and
soils derived from these rock types, may be corrosive to concrete or metal, causing damage to
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
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structures built upon them. The potential for the Happle soils have a high potential of corrosion
to uncoated steel, but a low potential of corrosion to concrete. This is not expected to be an
issue with the proposed development since the project involves construction of a produced
water pond. This site was previously developed for use as a produced water storage facility.
Some Tertiary and Cretaceous age sedimentary rocks with high clay content are capable of
accepting water into their chemical structure and expand many times their volume when dry.
These sedimentary rocks, and soils formed from these rock types, may expand or contract as
they become wet and then dry out resulting in damage to structures built upon them. Expansive
soil conditions are not expected to constitute a hazard at this Site.
3.8 Mudflow and Debris Fan Areas
The Pond 10 Site is not located in an area mapped as having mudflows or debris fans.
However, it appears that there is a drainage on the north side of the Pond 10 Site and there
does appear to have small debris fans supporting vegetation to the northeast of the Site. There
is also a slide area and debris fan to the east-southeast of the Site. The toe of the slide is close
to the location of the proposed stormwater retention pond. There is a slope and escarpment
adjacent to the Site and they have built a berm to channel water away from the pads.
Engineering controls may be needed to divert debris fans away from the Site.
3.9 Development Over Faults
No significant faulting is known in the project area, but some jointing may occur in proximity to
the folds mentioned in the structural geology section. Three narrow down-dropped block valleys,
known as grabens, and bound by normal faults are present along a northwest trending fracture
zone several miles north of the Pond 10 Site. The maximum stratigraphic displacement on these
faults does not exceed 120 feet and most displacements are considerably less. Small northwest
striking faults between the graben in the central part of Township 4 South, Range 97 West and
the graben in southwestern part of Township 4 South, Range 96 West suggest that the grabens
lie along a single fracture zone that extends for a total distance of approximately nine miles
(Hail, 1992).
According to the Geologic Map of the Red Pinnacle Quadrangle Map (Donnell et al, 1992) does
not show any faults in proximity to Pond 10 Site. There are no mapped faults in the immediate
vicinity of the proposed site.
Colorado is considered a region of minor earthquake activity; however, there is uncertainty due
to the relatively short historic record. According to the USGS Colorado Earthquake History
online, newspaper accounts were the primary source of earthquake data in Colorado prior to
1962. Few earthquakes have been reported in this part of Colorado. The Roan Plateau is not
in an area of known seismic activity; and therefore, earthquakes are not expected to present a
significant hazard.
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
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3.10 Flood Prone Areas
According to available information from the Federal Emergency Management Agency (FEMA)
National Flood Insurance Program, Flood Insurance Rate Map (FIRM), the site is not located
within the 100-year floodplain or 500-year floodplain. The Floodplain Map was prepared for
the vicinity of the town of De Beque and along the Colorado River. It is not in close proximity to
the Pond 10 Site. Flash floods could pose a hazard for the small intermittent drainage located
to the north of the Site. The engineering and design of the Pond 10 Site include a drainage plan
to address this issue and divert storm water away from the ponds.
3.11 Collapsible Soils
Collapsible soil conditions may be present in alluvial fan, alluvial, colluvial, and eolian
depositional environments, and are found in some areas along the Colorado River drainage
where fine-grained sediments have been deposited from higher elevations, but are not expected
to be present in the vicinity of the Pond 10 Site.
Collapsible soils are another type of subsidence that occurs in parts of Colorado where
unconsolidated sediments are present. This ground settlement can damage man-made
structures such as foundations, pavements, concrete slabs, utilities, and irrigation works.
Hydrocompactive soils are the most common type of collapsible soils. The presence or
introduction of water causes the soils to compact once they become wet. Hydrocompactive soils
form in semi-arid to arid climates in the western United States and large parts of Colorado in
specific depositional environments.
Collapsible soils have a low density and low moisture content where the grains are not packed
tightly together. These soils are strong in dry conditions, where the loose skeletal fabric of these
soils is preserved because the grains are “tack-welded” due to the presence of binding agents,
such as clay or silt, soil suction pressures, or other binding agents that can break, soften,
disperse, or dissolve when wet causing subsidence or settling. Silty clay and clayey sandy soils
onsite are potentially collapsible, although less likely onsite than subsidence due to expansive
soils.
3.12 Mining Activity
A review of the Red Pinnacle 7.5-minute topographic map shows several drill holes for
exploration of oil shale, but does not show underground mining of oil shale in the vicinity of the
Pond 10 Site. Subsidence is not expected to be a geologic hazard affecting the Pond 10 Site.
3.13 Radioactivity
According to Colorado Geologic Survey Bulletin 40, Radioactive Mineral Occurrences of
Colorado, the only naturally occurring radioactive mineral occurrences in Garfield County
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Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
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include uranium and vanadium deposits that occur near the town of Rifle (Nelson-Moore,
Collins, Hornbaker, 2005). These deposits are located in older Jurassic age sediments, are not
exposed in the vicinity of the site, and lie stratigraphically below the zones that are developed
for oil and gas production. Therefore, radioactivity is not expected to pose a hazard.
The Colorado Department of Public Health and Environment (CDPHE) has posted a statewide
radon potential map on their website based on data collected by the EPA and the U.S.
Geological Survey. Garfield County and most of Colorado has been mapped as being within
Zone 1 – High Radon Potential, or having a high probability that indoor radon concentrations will
exceed the EPA action level of 4 picocuries per liter (pCi/L).
Radon is not expected to be a hazard at the Pond 10 Site since the site will generally not be
occupied for extended periods and will not have occupied structures containing basements or
substructures in which radon can accumulate. Colorado oil and gas operations are not known
to have a significant problem with naturally occurring radioactive materials (NORM) or
technologically enhanced naturally occurring radioactive materials (TENORM); however, there
have been some instances where pipe scale has contained radium and associated radon gas.
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
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4.0 Conclusions and Recommendations
The following conclusions and recommendations were made following a review of the available
site data for natural and geologic hazards in the vicinity of the Oxy Pond 10 storage Site located
in Garfield County, Colorado.
Geologic hazards were identified in the immediate vicinity of the Oxy Pond 10 Site.
These include steep slopes and potential landslides, debris flow, and rock fall.
Avalanche areas are present in the northeastern parts of Garfield County in parts of the
Park Range and Flat Tops mountain range. Avalanche conditions are not expected to
be a hazard in area of the Pond 10 Site.
Landslide areas have not been mapped in the vicinity of the Pond 10 Site. However,
there is evidence of slides or debris flows located to the northeast and east-southeast of
the Pond 10 Site.
Rockfall areas are present to the south along steep cliff faces of the Conn Creek Canyon
and Gilman Gulch. Rockfall mitigation should be designed by a qualified licensed
professional engineer in accordance with Section 4-203 and 7-108 of the LUDC.
Alluvial fan hazard areas are not present in the vicinity of the Pond 10 Site, but are
present further to the south in some areas along the Colorado River drainage.
Slope development is not expected to be an issue on the Pond 10 Site, but there are
steep slopes to the northeast and east of the Site. Engineering controls may be needed
to control rock fall and slides.
Corrosive or expansive soils and rock are not present in the vicinity of the Pond 10 Site.
Collapsible soils are not present in the vicinity of Pond 10 Site.
No significant faulting is known in the Pond 10 Site.
No flood prone areas are mapped in the vicinity of the Pond 10 Site. Flash flooding is an
issue for lower elevations along Conn Creek, and areas along the Colorado River are
prone to flood risks.
There are no mining activities shown in the vicinity of the site.
There are no naturally occurring radioactive mineral deposits known in the site area.
NORM/TENORM may be an issue with exploration and production.
The Pond 10 Site is not expected to have any occupied structures constructed on it, and the
Site will be used for the storage of produced water. Slopes to the north and east are potentially
unstable. An access road and diversion ditch have been constructed around the perimeter of
the produced water pond. There is a setback of approximately 25 feet to 30 feet from the
slopes to the east and northeast. These engineering controls are expected to mitigate potential
rockfall, slides, or debris flows from steep slopes to the northeast and east. Appropriate risk
mitigation design should be determined by a qualified, licensed professional engineer should be
performed as a part of this upgrade development.
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
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5.0 Natural and Geologic Hazard Report Background
Garfield County Colorado finalized the Land Use and Development Code (LUDC) with an
effective date of July 15, 2013. According to Section 7-108 Use of Land Subject to Natural
Hazards of the Garfield County LUDC “Land subject to identified Natural and Geologic Hazards,
such as falling rock, landslides, snow slides, mud flows, radiation, flooding, or high water tables,
shall not be developed unless it has been designed to eliminate or mitigate the potential effects
of hazardous site conditions as designed by a qualified professional engineer and as approved
by the County.”
The LUDC requires a Natural and Geologic Hazard Study be prepared by a qualified
professional geologist be submitted with a development plan or plat. The LUDC defines a
geologic hazard as “A geologic phenomenon that is so adverse to past, current, or foreseeable
construction or land use as to constitute a significant hazard to public health and safety or to
property.”
The LUDC defines a Hazard Area as “An area that contains or is directly affected by a geologic
hazard, including but not limited to the following types of areas.”
A. Avalanche Area. “A mass of snow or ice and other material that may become
incorporated therein as such mass moves rapidly down a Slope.”
B. Landslide Area. “An area with demonstrably active mass movement of rock and
soil where there is a distinct surface rupture or zone of weakness that separates
the landslide material from more stable underlying material.”
C. Mudflow Debris Area. “An area subject to rapid mud and debris movement or
deposit occurring after mobilization by heavy rainfall or snowmelt runoff. Such
areas are formed by successive episodes of deposition of mud and debris.”
D. Radioactive Area. “An area subject to various types of radiation emission from
radioactive minerals that occur in natural or manmade deposits of rock, soil, or
water.”
E. Potentially Unstable Soils. “An area of land identified as having soils that may
cause damage to structures, such as buildings and roadways, as a result of over
saturation or some other outside influence.”
According to the Garfield County LUDC Section 4-203 Description of Submittal Requirements,
the professional qualifications for preparation and certification of certain documents required by
this Code are as follows:
“Geologist. Geology reports shall be prepared by either a member of the American
Institute of Professional Geologists, a member of the Association of Engineering
Geologists, or a qualified geotechnical engineer licensed in the State of Colorado.”
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Garfield County, CO March 2014
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A search of the Colorado Department of Regulatory Agencies (DORA), Licensed Professionals
and Businesses indicates that Colorado licenses “professional engineers” and “engineer interns”
but does not appear to have a license specific to “geotechnical engineers.”
Currently the state of Colorado does not require licensure or registration of geologists.
Colorado Revised Statutes do require that geologic reports be prepared or authorized by a
professional geologist.
“Professional Geologist” is a term defined in Colorado Statutes.
The references for these Statutes are shown here:
34-1-201. Definitions. As used in this part 2, unless the context otherwise requires:
(1) “Geologist” means a person engaged in the practice of geology.
(2) “Geology” means the science which treats of the earth in general; the earth’s
processes and its history; investigation of the earth’s crust and the rocks and other
materials which compose it; and the applied science of utilizing knowledge of the
earth’s history, processes, constituent rocks, minerals, liquids, gases, and other
materials for the use of mankind.
(3) “Professional geologist” is a person who is a graduate of an institution of higher
education which is accredited by a regional or national accrediting agency, with a
minimum of thirty semester hours (forty-five quarter) hours of undergraduate or
graduate work in a field of geology and whose post baccalaureate training has been in
the field of geology with a specific record of an additional five years of geological
experience to include no more than two years of graduate work.
(4) 34-1-202. Reports containing geologic information. Any report required by law or by
rule and regulation, and prepared as a result of or based on a geologic study or on
geologic data, or which contains information relating to geology, as defined in section
34-1-201 (2), and which is to be presented for any state agency, political subdivision
of the state, or recognized state or local board or commission, shall be prepared or
approved by a professional geologist as defined in section 34-1-201(3).
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
13
6.0 Professional Geologist Certification
By means of this certification, I attest that:
- I am qualified to prepare a Natural and Geologic Hazard Study in accordance with
the provisions of Section 7-207 of the Garfield County LUDC and that I am a member
of the American Institute of Professional Geologists per LUDC 4-203.
- I am familiar with the geology of the area of the proposed Oxy located in the SE ¼,
SW ¼, Section 5, Township 7 South, Range 97 West, 6th Principal Meridian in
Garfield County, Colorado.
- Although the Colorado Geological Survey does not currently have a licensing or
registration program for professional geologists practicing in the state of Colorado,
there are requirements within local and State statutes that require that geologic
reports be prepared by a professional geologist. I attest that I meet the requirements
of the Colorado Geological Survey’s definition of a professional geologist having
completed and met the educational requirements of the Colorado Geological Survey
definition.
- I have a Bachelors of Science degree from Colorado State University and have been
employed as a professional geologist since 1991.
- I am a licensed Professional Geologist and Professional Geoscientist in other States,
including Texas, Utah, and Wyoming which do have licensing programs for
professional geologists.
- I have reviewed published geologic maps and reports applicable to this area and
have considered the implications of these conditions in the context of the proposed
development.
- This report has been prepared in accordance with good scientific principles and
engineering practices including consideration of applicable industry standards, and
with consideration of the requirements of the National Association of State Boards of
Geology. The conclusions and recommendations contained in this report are based
on information available and known to me at the time of this report. Good scientific
principles and standard engineering practices were taken into consideration to in
arriving at the conclusions and recommendations made in this report.
James W. Hix
Senior Geologist
Date: __03/18/2014_____
Note: The PG’s certification does not relieve the owner/operator of the facility of the duty to review this report or fully implementing
the recommendations in accordance with all applicable Federal, State, and local requirements in order to achieve the desired goals
or objectives.
Geologic Hazard Report Olsson Associates
Oxy Pond 10 Facility Golden, Colorado
Garfield County, CO March 2014
OA Project #013-0656
14
7.0 References
Alstatt, D.K., 2003, Soil Survey of Douglas-Plateau Area, Colorado Parts of Garfield and
Mesa Counties, U.S. Department of Agriculture, Soil Conservation Service, in
cooperation with the Colorado Agricultural Experiment Station 355 p., 1 pl, 46 map
sheets
Czyzewski, G., Chapter 12 – The Piceance Creek Basin, Colorado Ground-Water
Association, Ground-Water Atlas, 1999 p 63-66.
Donnell, J.R., Schmitt, L.J., Smith M.C., 1992, Geologic Map of the Red Pinnacle
Quadrangle, Garfield County, Colorado, U.S.G.S., Map MF-2202; scale 1:24,000
DR Griffin & Associates, Inc. Oxy USA Pond 10 Upgrade, Issued for Bid Drawing Set,
March 6, 2014
Grout, M. A. and Verbeek, E.R., 1992, U.S.G.S. Bulletin 1787-Z, Fracture History of the
Divide Creek and Wolf Creek Anticlines and Its Relation to Laramide Basin-Margin
Tectonism, Southern Piceance Basin, Northwestern Colorado, 32 p.
Hail, W.J., Jr., 1992, U.S.G.S. Bulletin 1787-R, Geology of the Central Roan Plateau
Area, Northwestern, Colorado, 26 p.,
Nelson-Moore, J.L., Bishop Collins, D., Hornbaker, A.L., 2005, Colorado Geologic
Survey, Bulletin 40, Radioactive Mineral Occurrences of Colorado, pp 154-158 (CD)
Robson, S.G. and Banta, E.R., 1995, U.S.G.S. Hydrologic Investigations Atlas 730-C,
Groundwater Atlas of the United States, Segment 2, Arizona, Colorado, New Mexico,
Utah, 32 p.
Online References
Colorado Oil and Gas Conservation Commission http://cogcc.state.co.us/
Natural Resources Conservation Service - Soil Survey http://www.nrcs.usda.gov/
Garfield County
Slope Hazards: http://garfield‐county.com/geographic‐information‐
systems/documents/6439291200422slopehaz.pdf
Soil Hazards: http://garfield‐county.com/geographic‐information‐
systems/documents/64335291200423soilhaz.pdf
Surficial Geology of Garfield County: http://garfield‐county.com/geographic‐
information‐systems/documents/geologic‐hazards/24surfgeo.pdf
Colorado Geological Survey website: http://geosurvey.state.co.us/hazards
Colorado Geological Survey website: http://geosurvey.state.us/land/Pages/Professional
Geologist
Colorado Oil and Gas Conservation Commission website:
http://dnrwebcomapg.state.co.us/mapguide2010/
FIGURES
T6S R97W
216921400026OXY USA INC7,733 Acres216921400026
216736200023
241101300001
241110100015
213732100008
216912200012
241134200956
216902200019
241104100002
216904400003
216910100020
241108200954241311200951
213532100009213725300007213715300009 213725300007
216914100022
216927200017
213529100008
240907300953
241108200011
213533400010
216911400011
216901200001
213527300015
216904100951
216901100027
216701400020
217131100006
241325100016
213715300009
241104400951
213534300957
241108100953
241109200955
213722300003
241104300952241108200019
240918100027
216711300954
213736200952
213715300009
-
213-CONN
CREEK
RD
OXY USA WTP LPO XY USA WTP LP
760 Horizon Drive, Suite 101Grand Junction, CO 81506
Pond 10 N/S Complex
Adjacent Parcels
Oxy property - subject parcel
Oxy Responsible Road
Unimproved Public Road
Gravel Public Road
Paved Public Road
Map Revised: Aug 6, 2013
Pond 10 N/S ComplexLocation Map
00.551.11.652.2Miles
Garfield County, Colorado
Pond 10 N/S Complex
!@
Pond 10N/S Complex
EPCO Tie In Facility
T7S-R97W
T6S-R97W
T7S-R98W
T6S-R98W
009008
005 004
017 016018
007
006
029 028030
032 033
031
036
001
012
013
025
015
010
019024
003
213 - CONN CREEK RD
OXY USA WTP LPOXY USA WTP LP
760 Horizon Drive, Suite 101
Grand Junction, CO 81506
Pond 10N/S Complex
!@ OXY Guard Shack
Oxy responsible road
Unimproved Public Road
Gravel Public Road
Paved Public Road
April 16, 2013
Pond 10 N/S Complex
Proposed Centralized E&P Facility
00.150.30.450.60.75Miles
Garfield County, Colorado
213 - CONN CREEK RD
OXY USA WTP LPO XY USA WTP LP
760 Horizon Drive, Suite 101Grand Junction, CO 81506
Pond 10 N/S Complex
Parachute Creek Memeber and lower part (undifferentiated)
Green River Formation
Wasatch Formation
Oxy Responsible Road
Unimproved Public Road
Gravel Public Road
Paved Public Road
Map Revised: Aug 6, 2013
Pond 10 N/S ComplexGeology Map
00.10.20.30.40.5Miles
Garfield County, Colorado
213 - CONN CREEK RD
OXY USA WTP LPO XY USA WTP LP
760 Horizon Drive, Suite 101Grand Junction, CO 81506
Biedsaw-Sunup gravelly loams, 10-40 % slopes
Happle very channery sandy loam, 3-12 % slopes
Happle-Rock outcrop association, 25-65% slopes
Pond 10 N/S Complex
Oxy Responsible Road
Unimproved Public Road
Gravel Public Road
Paved Public Road
Map Revised: April 18, 2013
Pond 10 N/S ComplexSoils Map
00.050.10.150.2Miles
Garfield County, Colorado
C
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213 - CONN CREEK RD
OXY USA WTP LPO XY USA WTP LP
760 Horizon Drive, Suite 101Grand Junction, CO 81506
Stream Network
Intermittent Stream
Perennial Stream
Pond 10 N/S Complex
Oxy Responsible Road
Unimproved Public Road
Gravel Public Road
Paved Public Road
Map Revised: April 18, 2013
Pond 10 N/S ComplexSurface Water Map
00.050.10.150.2Miles
Garfield County, Colorado
200 -
492
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OXY USA WTP LPOXY USA WTP LP
760 Horizon Drive, Suite 101
Grand Junction, CO 81506
Pond 10 N/S Complex
Floodplain (accessed through Mesa County GIS)
Oxy Responsible Road
Unimproved Public Road
Gravel Public Road
Paved Public Road
Map Revised: April 18, 2013
Pond 10 N/S Complex
Floodplain Map
00.511.52Miles
Garfield County, Colorado
Pond 10 N/S Complex