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3.5 Surface Waters, Wetlands and Aquatic Ecology 

3.5.1 Surface Waters 

The Permit Area is located in the Basin, a topographically closed system that 

drains internally due to a divergence in the Continental Divide. Figure 1.2-1 

shows the location of the Permit Area within the Basin. Runoff from precipitation 

or snowmelt within the Basin infiltrates into the soils, is evaporated or transpired, 

or drains to low areas within the Basin, forming seasonal playa lakes. Due to the 

fact that all of the channels are ephemeral and that the Permit Area lies within a 

closed, isolated basin, no surface water features on the property connect to a 

tributary of a navigable water body. As such, no surface waters within the Permit 

Area are considered waters of the US under the jurisdictional authority of the US 

Army Corps of Engineers (USACE). However, surface waters within the Permit 

Area are considered ‘waters of the state’ (WS 35-11-103(c)(vi)), and are afforded 

protection under State and BLM regulations (RMP Page 3-127)(BLM, 2008c) 

Section 3.10 describes the meteorological and climatic conditions of the Basin 

and the Permit Area in detail. Due to the arid climate and high infiltration 

capacity of the soils, all of the streams in the Permit Area are ephemeral; there are 

no perennial or intermittent drainages in the Permit Area, according to the 

conventional definition by Meinzer (1923) and as applied by BLM (1998): 

Perennial - A stream that flows continuously. Perennial streams 

are generally associated with a water table in the localities through 

which they flow. 

Intermittent - Intermittent streams receive their base flow from 

groundwater and flow is augmented by seasonal events such as 

precipitation or snowmelt runoff. 

Ephemeral – Ephemeral streams are seasonal and have no 

contribution from groundwater; they only flow in direct response 

to seasonal events such as precipitation or snowmelt runoff. 

Based on the loam and sandy-loam soils found at the site, the steady-state 

saturated infiltration rate under laboratory conditions is estimated at 0.2 to 0.8 

inches per hour (Hillel, 1980). However, the practical infiltration rate is likely 

much higher because saturated conditions are rare, and more macropores are 

present under field conditions and at large scales. Infiltration-excess (Hortonian) 

overland flow has not been observed at the site, except on the compacted soils 

found in existing two-track roads. When present, runoff is conveyed by numerous 

ephemeral channels that are vegetated by sagebrush and do not support aquatic 

life. Alluvial deposits, if any, along drainages are not extensive, and the shallow 

groundwater table is typically 150 to 200 feet below ground surface (Section 

3.6.2.1). 

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3.5.1.1 Surface Water Features 

Figure 3.5-1 shows the surface water features in the main Permit Area; and 

Figure 3.5-2 shows the features along the East and West Roads to the Permit 

Area. The main Permit Area consists of three principle watersheds that, together,

drain greater than 99 percent of the main Permit Area. Only one drainage in the 

main Permit Area is named on the USGS 1:24,000 scale topography maps: Battle 

Spring Draw. For the purposes of the WDEQ-LQD Permit to Mine (LCI, 2011b),

the principle drainages were named Western Draw, West Battle Spring Draw, and 

East Battle Spring Draw by LCI. 

The Western Draw watershed covers 2.9 square miles, of which 2.4 square miles 

are within the Permit Area; the West Battle Spring Draw watershed covers 7.0 

square miles, of which 3.1 square miles are within the Permit Area; the East 

Battle Spring Draw watershed covers 5.1 square miles, of which 1.0 square mile 

is within the Permit Area. The entire main Permit Area drains into the Battle 

Spring Flat, approximately nine miles southwest of the Permit Area. 

The East Road to the Permit Area is in the Stratton Draw and East Fork Stratton 

Draw watersheds, both of which are shown on USGS 1:24,000 scale topography 

maps. The Stratton Draw Watershed is 13.8 square miles, of which 0.02 square 

miles are in the Permit Area. The East Fork Stratton Draw is 5.6 square miles, of 

which 0.03 square miles are in the Permit area. No substantial drainages cross the 

East Access Road in the East Fork Stratton Draw watershed. 

The West Road is within the Eagles Nest Draw and Far Western Draw 

watersheds, both of which are shown on USGS 1:24,000 scale topography maps. 

The Eagles Nest Draw watershed is 16,021 acres, of which 16.6 acres are within 

the Permit area, and the Far Western Draw is 2,618 acres, of which 68.5 acres are 

within the Permit Area. The road traverses the ridgeline that divides these 

watersheds, and does not cross any significant drainages. 

Figure 3.5-3 shows a longitudinal profile of the main channel in each of the 

primary watersheds within the main Permit Area, and the endpoints are shown in 

Figure 3.5-2. Within the Permit Area, the average slope of the main channel in 

the Western Draw, West Battle Spring Draw, and East Battle Spring Draw 

watersheds is 1.4, 1.2, and 1.1 percent, respectively. The sinuosity (channel 

length divided by valley length) of the main channels are 1.24, 1.10, and 1.03, 

respectively, and the drainage density is 3.0, 4.2, and 5.0 miles per square mile, 

respectively. 

The ephemeral channels are typically trapezoidal and U-shaped in cross-section; 

they are approximately ten to 15 feet wide, and incised three to six feet near the 

downstream Permit Area boundary. Channel side slopes generally range from 1:1 

to 2.5:1; however, vertical and slumping banks occur in areas of active erosion. 

The bed material in the larger drainages is sandy in texture and non-cohesive. 

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Figure 3.5-3 Longitudinal Profiles of the Main Permit Area’s Principle Drainages 

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One small (less than one-quarter acre) seasonal stock pond, Crooked Well 

Reservoir, is located in the northeast portion of the Permit Area (Figure 3.5-1).

The reservoir detains seasonal flow behind a dirt berm across East Battle Springs 

Draw (Figure 3.5-4) and is used by cattle, wild horses, and wildlife as a water 

source. Crooked Well Reservoir fills in March or April, when there is sufficient 

snowmelt runoff in East Battle Springs Draw, and is dry for most of the year. 

Figure 3.5-4 Crooked Well Reservoir 

Looking southwest. 

April 2006. 

Looking west. 

April 2009. 

Looking north. 

April 2007. 

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Field personnel (with formal training in hydrology), working on-site from 2006 

through 2009, visually and conservatively estimated the flow of an on-site 

streamflow event at 0.5 cubic feet per second (cfs). This streamflow event was in 

response to snowmelt in the springtime. Due to the lack of disturbance of bed 

sediment and litter in the ephemeral channels, the low slope of the area, and the 

paucity of overland flow in response to observed rainfall events, it is believed 

that no flows greater than 1.0 cfs occurred during that period. Low flows, while 

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3.5.1.2 Streamflow 

The long-term mean annual precipitation is approximately ten inches per year in 

the Project region. April, May, and June are the wettest months, as discussed in 

Section 3.10.1.2

iltration capacity of the

wmelt (Figure 3.5-5)

. Annual runoff is very low due to the dry climate and high 

inf soils. Runoff generally occurs as a result of spring 

sno or, less frequently, in response to large summer 

thunderstorms. The quantity of spring runoff is variable, depending on the 

amount of winter snowfall accumulation. Peak flows are driven by high intensity 

rain events, but surface flow from rainfall is generally short-lived. 

Figure 3.5-5 Typical Snowmelt Runoff 

Approximately 15 miles northeast of the Permit Area in April 2007 
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present, were dispersed across the channels and too shallow to measure using

standard velocity-area methods (Figure 3.5-5). 

Peak flows were estimated using a statistical regression model developed for 

Wyoming by Miller (2003). Peak flows for the smallest of the three watersheds 

in the main Permit Area, Western Draw, were estimated as 17 cfs for the two-year 

event and 227 cfs for the 100-year event; peak flows in the largest watershed in 

the main Permit Area, West Battle Springs Draw, were estimated as 29 cfs for the

two-year event and 344 cfs for the 100-year event. Stratton Draw is the only 

significant channel that would generate substantial peak flows in the East and 

West Road portions of the Permit Area. The calculated two-year and 100-year 

peak discharges for this watershed are 43 and 477 cfs, respectively. Actual peak 

runoff rates may be lower because of the high infiltration capacity of the soils. 

The deeply incised channels are expected to convey and contain peak flows 

within their banks. 

3.5.1.3 Surface Water Quality 

Under the WDEQ-WQD Classification, Battle Spring Draw is listed as a Class 3B 

water body. Beneficial uses for Class 3B waters can include recreation, wildlife, 

“other aquatic life”, agriculture, industry, and scenic value, but do not include 

drinking water, game fish, non-game fish, and fish consumption. Water quality 

data of samples collected in 1975 and 1976 from Battle Spring Draw for the

Sweetwater Uranium Mill and Mine near the Permit Area are presented in Table 

3.5-1 (Sheperd Miller, 1994). The pH was highly alkaline at 9.5 standard units 

(SU). Uranium concentrations ranged from 0.006 to 0.95 mg/L. 

Storm Water Samplers, fitted with Nalgene bottles, were installed to collect oneliter grab samples of first flush streamflow during runoff events (Figure 3.5-6).

The sampling locations were selected based on their topographic potential to 

concentrate the ephemeral surface flows. In April 2006, samplers were installed 

at 12 locations in the main Permit Area (LC1 through LC12 on Figure 3.5-7). In 

April 2007, an additional sampler (LC13) was added to represent an area in the 

southeastern corner that was added to the Permit Area in the summer of 2006.

Three of these locations were selected to capture runoff as it enters the main 

Permit Area from the upstream side (LC6, LC11 and LC12), and the others 

capture runoff within the main Permit Area (LC1, LC2, LC3, LC5 and LC10) or 

at the downstream boundary (LC4, LC7, LC8, LC9 and LC13). In September 

2009, two samplers (LC14 and LC15) were added along Stratton Draw, upstream 

and downstream of the East Access Road (Figure 3.5-7). 
Table 3.5-1 Historic Surface Water Data – Battle Spring Draw 

Sample Date 1975 1976

July April June August October July

Sodium (mg/L) 116 -- -- -- -- --

Potassium (mg/L) 8 -- -- -- -- --

Calcium (mg/L) 23 -- -- -- -- --

Magnesium (mg/L) 5 -- -- -- -- --

Sulfate (mg/L) 130 -- -- -- -- --

Chloride (mg/L) 18 -- -- -- -- --

Carbonate (mg/L) 0 -- -- -- -- --

Bicarbonate (mg/L) 220 -- -- -- -- --

TDS (mg/L) 276 -- -- -- -- --

pH (SU) 9.5 -- -- -- -- --

Gross Alpha (pCi/L) -- -- -- 156 ± 34 -- --

Gross Beta (pCi/L) -- -- -- 90.3 ± 8.8 -- --

Thorium-230 (pCi/L) -- -- -- 3.34 ± 0.43 -- --

Radium-226 (pCi/L) -- -- -- 33.5 ± 1.1 -- --

Strontium-90 (pCi/L) -- -- -- 1.5 ± 0.6 -- --

Uranium (mg/L) 0.006 0.153 0.153 0.289 0.95 0.5

pCi/L = picoCuries per liter 

-- = No data 

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Figure 3.5-6 Storm Water Sampler 

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Seven of the samplers in the main Permit Area collected full, one-liter samples 

from snowmelt runoff in March and April 2007. These samples were retrieved on 

April 17, 2007. No water (or insufficient water for analysis) was collected in the 

other samplers. The water quality data for the seven surface water samples are 

summarized in Table 3.5-2. Ionic strength was low in all samples, which is 

probably due to the majority of the sample being snowmelt. For all samples, the 

dissolved and total concentrations of trace metals were near or below the 

detection limit. Radiometric parameters, including uranium, lead-210, polonium210, and thorium-230, were generally below detection with the exception of 

dissolved uranium, which was detected at very low concentrations (0.0003 to 

0.0004 mg/L) in two samples, suspended uranium (0.0003 to 0.0009 mg/L) in two 

samples, and total uranium (0.0003 to 0.0009 mg/L) in four samples. Total 

radium-226 was detected at a low concentration (0.5 pCi/L) in one sample. This 

was the LC2 location in one of the larger channels in the center of the Permit 

Area. Gross alpha was also detected in small amounts (1.1 to 3.6 pCi/L) in six 

samples. The highest concentration was 3.6 pCi/L and was again from the LC2

location. The pH of the samples was slightly acidic to neutral, ranging from 6.39 

to 7.12 SU. Conductivity was low with no more than 100 micromhos per 

centimeter (μmhos/cm) for all samples. 

In general, the quality of water was very good for all samples. The radiometric 

parameters detected in the LC2 sample correlate well with the radiological scans 

of the Permit Area. This central area has the highest radioactive activity, as 

indicated by the results from the radiological surveys. Still, the levels are well 

below all Wyoming agricultural and drinking water standards. Differences 

between the 2007 and historical data could be attributed to either a difference in 

streamflow during the sampling period or differences in the sampling locations. 

3.5.1.4 Surface Water Uses 

Surface-water permits with legal descriptions inside and within three miles of the 

main Permit Area were queried using the WSEO Water Rights Database (WSEO, 

2010). Table 3.5-3 lists the twelve surface water permits within three miles of the 

Permit Area. None of these locations are within one mile of the Permit Area, and 

all are related to mining operations to the southwest of the Permit Area. 

There are four BLM wells within one mile of the main Permit Area. These wells 

have stock ponds associated with them. Stock ponds are typically used for 

overflow water whenever wells are pumped to provide water to wildlife, 

livestock, or wild horses. The water-use permits for these ponds are associated 

with the wells that supply the ponds, i.e., they are not associated with any surfacewater-use permits. These wells are described in more detail in Section 3.6.3.1.

As noted in the previous section, the Crooked Well Reservoir (Figure 3.5-1) is in 

the Permit Area. However, it is a small off-channel detention pond, less than onequarter acre in size, and there is no water-use permit associated with it. 

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Table 3.5-2 Surface Water Quality Data (Page 1 of 5) 

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Table 3.5-2 Surface Water Quality Data (Page 2 of 5) 

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Table 3.5-2 Surface Water Quality Data (Page 3 of 5) 

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Table 3.5-2 Surface Water Quality Data (Page 4 of 5) 

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Table 3.5-2 Surface Water Quality Data (Page 5 of 5) 

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Table 3.5-3 Surface Water Rights within Three Miles of the Main Permit Are

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3.5.2 Wetlands 

Evaluation of potential wetland areas was initially conducted by reviewing aerial 

photographs of the Permit Area for topographic low areas and drainages. Other 

than the Crooked Well Reservoir, no potential wetland areas were identified from 

the aerial photographs. Three potential wetlands were identified using the 

Geographic Information System (GIS) layers from the National Wetlands 

Inventory (NWI) database (National Wetlands Inventory, 2006), and their

locations are shown in Figure 3.5-8. The National Hydrography Dataset (NHD) 

was also referenced (National Hydrography Dataset, 2011), this dataset only 

showed the Crooked Well Reservoir (Figure 3.5-8) as a potential wetland. 

The potential wetland areas were visited in the field during the 2006 growing 

season and again in the spring of 2009. The sites were evaluated using the criteria 

listed in the USACE wetland delineation manual (Department of the Army, 

1987). Two of the three locations were not wetlands, as none of the criteria 

related to hydrology, soils, or vegetation were met. A more detailed evaluation of 

the vegetation at one potential location, the Crooked Well Reservoir, was 

conducted because of the potential for inundation of the area during some 

seasons. The indicator status for wetland species has been developed by the 

USFWS, and a specific publication for Region 9 (which includes western 

Wyoming) is available (Reed, 1988). 

Based on more detailed field observations during April 2006 (vegetation survey, 

surface water sampling, and other site activities), the Crooked Well Reservoir was 

determined not to be a wetland under the 1987 USACE criteria (hydrology, soils, 

and vegetation). Figure 3.5-4 shows the reservoir conditions in April of 2006, 

2007, and 2009. Hydrology is the criteria most likely to be met in a given year; 

however, the variability and timing of precipitation do not result in inundation for 

at least five days during the growing season each year. There may be sufficient 

snowmelt for water to accumulate for five days in some years, but because of the 

variability in temperatures, snowmelt often occurs (and the reservoir dries) before 

the growing season starts in June (National Climatic Data Center, 2008). There 

may also be water present after an intense summer thunderstorm, but only at rare 

intervals from year to year. 

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The bottom of the reservoir is composed of sand, silt, and clay, with no surficial 

evidence of extensive organic material or anaerobic conditions. The bottom of 

the reservoir is essentially bare, probably due in part to wind scour. Although 

there is no specific vegetation density requirement for wetlands, the density is a 

factor that should be taken into account (Department of the Army, 1987). 

Scattered small sagebrush and grasses are present along the edges of the bare 

area; these grade quickly to the more dense sagebrush community, however 

hydrophytic plants were not observed. 

Of the other two potential wetlands identified in the NWI, one is off channel in 

the northern portion of Township 25 North (T25N), Range 93 West (R93W), 

Section 24 (Figure 3.5-9). The other location is near a channel and just south of 

the Permit Area. It was apparently associated with the BLM Battle Spring Draw 

Well No. 4451 in the northern portion of T25N, R92W, Section 21. When the site 

was first visited in April 2006, and again in November 2007, the well was not in 

use. However, the well is back in service and was visited in April 2009 and 

October 2011 (Figure 3.5-10).

3.5.3 USACE Jurisdiction 

In May 2010, LCI submitted a request to USACE for a jurisdictional 

determination of waters within the Permit Area, based on the information in 

Appendix D11 of the WDEQ-LQD Permit to Mine (LCI, 2011b), which is 

essentially the same information in this EIS. The USACE’s jurisdictional 

determination is in a letter dated August 10, 2010 (Attachment D11-1 of the 

WDEQ-LQD Permit to Mine [LCI, 2011b]). The information provided was 

determined to provide an accurate depiction of potential wetlands and other 

waters within the Permit Area. In addition, “all waters within the permit area do 

not contain any areas that meet the definition of waters of the United States”. The 

water bodies are considered isolated since: they have no surface connection to a 

traditional navigable water; they occur within a closed hydrologic basin; they do 

not provide habitat suitable for migratory birds; and they do not support any form 

of interstate commerce. 

3.5.4 Aquatic Ecology 

Research and field investigations confirmed that aquatic life was determined not 

to exist within the boundaries of the Permit Area. Surface water may be present 

occasionally, but it does not sustain aquatic life. 

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Figure 3.5-9 NWI Potential Wetland in T25N, R93W, Section 24 

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3.5-22 FINAL EIS Figure 3.5- NWI Potential Wetland at  attle Sring ra Well No. 445

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3.6 Groundwater 

This section summarizes the regional and local groundwater hydrology, including 

hydrostratigraphy, groundwater flow patterns, hydraulic gradient, and aquifer 

parameters. Data for this section of the report were obtained from the NRC 

Technical Report (LCI, 2010) and the WDEQ-LQD Permit to Mine (LCI, 2011b).

3.6.1 Regional Groundwater Hydrology 

The Permit Area is located in the northeastern portion of the Great Divide Basin, 

a closed basin with all surface water flows toward the interior of the basin. 

Existing data suggest that groundwater flow within the Basin is also 

predominately toward the interior of the basin (Collentine et al., 1981; Welder and 

McGreevy, 1966; and Mason and Miller, 2005). The Green Mountains located to 

the northeast, the Rawlins Uplift, Rock Springs Uplift, and Creston Junction, 

located east, southwest, and southeast, respectively, from the Permit Area, were 

identified as major recharge areas for aquifers within the basin (Fisk, 1967). The 

main discharge area for the Battle Spring/Wasatch aquifer system is to a series of 

lakes, springs, and playa lake beds near the center of the Basin. 

Hydrologic units of interest within the northeast portion of the Basin are shown 

on the stratigraphic column in Figure 3.6-1 and further described below, from 

deepest to shallowest: 

x Lewis Shale (aquitard between Tertiary and Mesaverde aquifer systems); 

x Fox Hills Formation (Cretaceous); 

x Lance Formation (Tertiary aquifer system); 

x Fort Union Formation (Tertiary aquifer system); 

x Battle Spring Formation-Wasatch Formation (Tertiary aquifer system);

x Undifferentiated Tertiary Formations (Upper Tertiary aquifer system, 

including Bridger, Uinta, Bishop Conglomerate, Browns Park, and South 

Pass); and 

x Undifferentiated Quaternary Deposits (Tertiary aquifer system). 

The Tertiary aquifer system has been identified as “the most important and most 

extensively distributed and accessible groundwater source in the study area” 

(Collentine et al., 1981). The term Tertiary aquifer system is used herein as the 

shallow Undifferentiated Quaternary Deposits through the Lance Formation. 

Although the Lance Formation is Cretaceous in age, Collentine et al. included it 

with the Tertiary aquifer system in the 1981 report, “Occurrence and 

Characteristics of Ground Water in the Great Divide and Washakie Basins, 

Wyoming”, and that convention was adopted by LCI for the Project. 

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The Battle Spring Formation of the Tertiary aquifer system crops out over most of 

the northeast portion of the Basin; and the Quaternary deposits and Upper Tertiary 

aquifer systems are absent or minimal in extent. In the northeast portion of the 

Basin, the shallower aquifer systems (Quaternary and Upper Tertiary) are 

typically found along the margins of the Basin where the Battle Springs 

Formation is absent, and in localized areas can be a source of groundwater. 

Aquifers in formations deeper than the Lewis Shale are generally too deep to 

economically develop for water supply or have elevated total dissolved solid 

(TDS) concentrations that render them unusable for human consumption. 

However in the northeast portion of the Basin, near structural highs such as the 

Rawlins Uplift, these aquifer systems can be sources of groundwater in the 

vicinity of outcrops. 

3.6.1.1 Lewis Shale 

The Lewis Shale a regionally extensive aquitard in the Basin underlies the Fox 

Hills Formation (Collentine et al., 1981). This unit is described by Welder and 

McGreevey (1966) as light to dark gray, carbonaceous shale with beds of siltstone 

and very fine-grained sandstone. The Lewis Shale is up to 2,700 feet thick, 

generally increasing in thickness toward the east side of the Basin. In the Permit 

Area, the Lewis Shale is 1,200 feet thick. Small quantities of water may be 

available from the thin sandstone beds within this unit near the margins of the 

Basin. The Lewis Shale acts as the confining unit between the Tertiary and 

Mesaverde aquifer systems (Collentine et al., 1981). 

3.6.1.2 Fox Hills Formation 

The Fox Hills Formation overlies the Lewis Shale and consists of very finegrained sandstone, siltstone and coal beds. It is not considered to be an important 

aquifer in the Permit Area. 

3.6.1.3 Lance Formation 

Overlying the Fox Hills Formation is the Lance Formation, consisting 

predominately of very fine-to fine-grained lenticular, clayey, calcareous 

sandstone. Shale, coal and lignite beds are present within the formation, which 

reaches a maximum thickness of approximately 4,500 feet (Welder and 

McGreevy, 1966). In the Permit Area, the Lance Formation is approximately 

3,000 feet thick. 

Collentine et al. (1981) include the Lance Formation (Aquifer) as the lower-most 

aquifer within the Tertiary aquifer system. However, the Lance Aquifer is 

included as part of the Mesaverde aquifer system by Freethey and Cordy (1991). 

Several stock wells, located along the eastern outcrop area of the Basin, are 

completed in the Lance Aquifer. The stock wells have estimated yields of five to 

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30 gpm. Hydraulic conductivity for the Mesaverde aquifer system reported by 

Freethey and Cordy (1991) (which, by the authors’ designation, includes the Fox 

Hills Sandstone, Lewis Shale, and Mesaverde Group, in addition to the Lance 

Aquifer) is reported to range from 0.0003 to 2.2 feet per day (ft/d). 

3.6.1.4 Fort Union Formation 

The Paleocene-age Fort Union Formation is between the Lance Formation and the 

overlying Wasatch and Battle Spring Formations, reaching a maximum thickness 

of approximately 6,000 feet within the Great Divide/Washakie Basin area. In the 

Permit Area, it is approximately 4,650 feet thick. The Fort Union Formation is 

present at or near land surface in a band around the Rock Springs Uplift and in the 

northeastern corner of the Basin (Mason and Miller, 2005). The Fort Union 

Formation is described as fine- to coarse-grained sandstone with coal and 

carbonaceous shale. Siltstone and claystone are present in the upper part of the 

formation (Welder and McGreevy, 1966). 

A potentiometric surface map, prepared by Natfz (1996) that groups the Fort 

Union aquifer with the Battle Spring/Wasatch aquifers, shows inferred movement 

of groundwater toward the Basin’s center (Figure 3.6-2).

The Fort Union aquifer is largely undeveloped and unknown as a source of 

groundwater supply except in areas where it occurs at shallow depths along the 

margins of the Basin. Well yields from the Fort Union aquifer within the Great 

Divide and Washakie Basins range from 3 to 300 gpm. Estimates of 

transmissivity for the Fort Union aquifer are highly variable, ranging from less 

than 3 square feet per day (ft2

/d) to325 ft2/d (Ahern et al., 1981) and (Collentine et 

al., 1981). 

3.6.1.5 Battle Spring Formation-Wasatch Formation 

The most important water-bearing aquifers within the Basin are in the Wasatch 

Formation and the Battle Spring Formation. The Wasatch and Green River 

Formations grade into the Battle Spring Formation in the northeastern portion of 

the Basin. The Battle Spring Formation is absent along the eastern margin of the 

Basin, near the county line between Sweetwater and Carbon Counties. The 

termination of the Battle Spring Formation to the east and north is abrupt, 

controlled largely by structural features, including the Rawlins Uplift to the east 

and the Green Mountains to the north. A dry oil test in Section 14, Township 24 

North, Range 90 West, located within a few miles of the eastern limit of the Battle 

Spring Formation, had a reported thickness of over 6,000 feet of fine- to coarsegrained sandstone that was interpreted by the American Stratigraphic Company as 

the Battle Spring Formation. Within the Permit Area, the Battle Spring Formation 

is over 6,200 feet thick. Figure 3.3-1 shows the regional geology of the area. 

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The Battle Spring Formation is described as an arkosic fine- to coarse-grained 

sandstone with claystone and minor conglomerates. There are typically several 

water-bearing sands within the Battle Spring Formation. The Battle Spring 

aquifers are included in the Tertiary aquifer system, as defined by Collentine et al. 

(1981). 

Groundwater within the Battle Spring aquifers is typically under confined 

conditions, although locally unconfined conditions exist. The potentiometric 

surface within the Battle Spring aquifers is usually within 200 feet of the ground 

surface (Welder and McGreevy, 1966). Most wells drilled for water supply in 

this unit are less than 1,000 feet deep. The potentiometric surface map of 

Wasatch and Battle Spring aquifers (Figure 3.6-3) indicates groundwater 

movement toward the center of the Basin (Welder and McGreevy, 1966). From 

the Permit Area, the potentiometric surface dips to the southwest at approximately 

50 feet per mile (ft/mile) (a hydraulic gradient of 0.01 feet per foot [ft/ft]). The 

hydraulic gradient becomes steeper near the margins of the Basin, where recharge 

to the aquifer is occurring. 

Wells completed in the Battle Spring aquifers typically yield 30 to 40 gpm; but 

yields as high as 150 gpm are possible. Pump tests conducted on 26 wells 

completed within the Battle Spring aquifers resulted in transmissivity values 

ranging from 3.9 to 423 ft2

/d, although most wells were less than 67 ft2/d. 

Specific capacity was less than one gallon per minute per foot for 23 of the 26 

wells tested (Collentine, et al., 1981). 

3.6.1.6 Undifferentiated Tertiary and Quaternary Sediments 

Undifferentiated Tertiary and Quaternary units above the Battle Spring/Wasatch 

Formations can be sources of water supply; but wells in the northeastern portion 

of the Basin are rare and generally limited to the margins of the Basin, where the 

Battle Spring Formation is not present. Commonly, along the margins of the 

Basin, hydrostratigraphic units younger than the Battle Spring/Wasatch have been 

deposited on rocks of Cretaceous age or older. Water supply wells along the 

margins of the Basin are often completed in both the older hydrostratigraphic 

units and Tertiary and Quaternary sediments. Water quality within these units 

tends to be variable and available resources of good quality water are limited. 

The undifferentiated Tertiary units consist of interbedded claystone, sandstone 

and conglomerate, with the coarser grained facies providing suitable groundwater 

resources where present. The undifferentiated Tertiary units are absent within the 

Permit Area and are not discussed further. 

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The undifferentiated Quaternary units consist of clay, silt, sand, gravel and 

conglomerates that are poorly consolidated to unconsolidated (Welder and 

McGreevy, 1966). These units represent windblown, alluvial and lake deposits. 

Where present, these deposits can provide acceptable yields of groundwater of 

relatively good quality. Thin deposits of Quaternary sediments are present within 

surface drainages in the Permit Area but are usually above the water table and 

unsaturated. Therefore, Quaternary sediments are not an important groundwater 

source in the vicinity of the Project and are not described further. 

3.6.2 Site Groundwater Hydrology 

LCI has collected lithologic, water level, water quality, and pump test data as part 

of its ongoing evaluation of hydrologic conditions for the Permit Area and, most 

recently, for MU1. In addition to LCI’s data, historic data collected for Conoco 

were used to support this evaluation (Hydro-Search, Inc., 1982). Drilling and 

installation of borings and monitor wells would continue to provide additional 

data to further refine the site hydrologic conceptual model and provide detailed 

operating information for each mine unit. Water level measurements, both 

historic and recent, provide data to assess potentiometric surface, hydraulic 

gradients and inferred groundwater flow directions for the aquifers of interest at 

the Permit Area. Long-term pump test data conducted by LCI and several 

shorter-term pump tests (Hydro-Engineering, 2007), as well as the pump tests 

conducted for Conoco (Hydro-Search, Inc., 1982), were used to evaluate 

hydrologic properties of the aquifers of interest. The pump test data were used to 

assess hydraulic characteristics of the confining units, and to evaluate impacts to 

the hydrologic system of the Fault through the Permit Area. 

Figure 3.6-4 shows the locations of the historic Conoco (or Texasgulf) monitor 

wells (the M-25-92 series), and it shows the locations of the existing monitor 

wells that were used for baseline data collection and in the LC16M and LC19M 

pump tests. Table 3.6-1 provides completion data for the monitor wells currently 

in use. Attachment D6-3 of the WDEQ-LQD Permit to Mine (LCI, 2011b)

includes well completion logs for those wells. Plate D5-3 in Appendix D5 of the 

WDEQ-LQD Permit to Mine shows the locations of all the existing monitor wells 

in the Permit Area. Figure 3.6-5 shows the monitor well locations for MU1; and 

Table 3.6-2 is a list of those wells. 

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Table 3.6-1 Permit Area Monitor Well Data (Page 4 of 4) 

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Table 3.6-2 Mine Unit 1 Monitor, Observation and Trend Wells 

Monitor Ring 

(M) Wells and 

Trend Well (TW) 1

Overlying 

Aquifer 

Monitor 

(MO) 

Wells 

Underlying 

Aquifer 

Monitor (MU) 

Wells and 

Observation 

Well (OW) 

Production 

Zone Monitor 

(MP) Wells 

M-101 M-116 MO-101 MU-101 MP-101

M-102 M-117 MO-102 MU-102 MP-102

M-103 M-118 MO-103 MU-103 MP-103

M-104 M-119 MO-104 MU-104 MP-104

M-105 M-120A 2 MO-105 MU-105 MP-105

M-106 M-121 MO-106 MU-106 MP-106

M-107 M-122 MO-107 MU-107 MP-107

M-108 M-123 MO-108 KPW-2 4 MP-108

M-109 M-124 MO-109 MU-109 MP-109

M-110 M-125 MO-110 MU-110 MP-110

M-111 M-126 MO-111 MU-111 MP-111

M-112 M-127 MO-112 MU-112 MP-112

M-113 M-128 MO-113 MU-113 MP-113

M-114 TW1-1 MO-114 3 OW1-1 ---

M-115 --- --- --- ---

1 Detailed monitor well information (e.g., well depths, screened intervals) provided in 

Attachment MU1 2-1 of the WDEQ-LQD MU1 documents (LCI, 2011b). 2 Well M-120 failed the MIT, was properly abandoned and was replaced with well M120A. 3 Well MO-114 was added to this list to ensure adequate monitoring near the Fault and 

associated splinter fault. 4 Well MU-108 failed the MIT, was properly abandoned and replaced with well KPW-2, 

which was originally used as a pump test well within the same horizon as and 17 feet 

from well MU-108.

3.6.2.1 Hydrostratigraphic Units 

As previously discussed in Section 3.3, the primary uranium production zone is 

identified as the HJ Horizon in the Battle Springs Formation. The HJ Horizon is 

subdivided into the Upper (UHJ), Middle (MHJ) and Lower (LHJ) Sands. The HJ 

Horizon is bounded above and below by aerially extensive confining units 

identified as the Lost Creek Shale and the Sage Brush Shale, respectively. 

Overlying the Lost Creek Shale is the FG Horizon. The deepest sand in the FG 

Horizon, the Lower FG (LFG) Sand, is the overlying aquifer to the HJ Horizon. 

Beneath the Sage Brush Shale is the KM Horizon. The uppermost sand within the 

KM Horizon, designated the Upper KM (UKM) sand, is a secondary production 

zone and also the underlying aquifer to the HJ Horizon. The No Name Shale unit 

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separates the UKM and Middle KM (MKM) Sand. The shallowest occurrence of 

groundwater within the Permit Area occurs within the DE Horizon, which is 

above the FG Horizon. A brief description of each hydrostratigraphic unit, from 

deepest to shallowest, is provided below and illustrated on a geophysical log on 

Figure 3.3-3.

DE Horizon 

The DE Horizon is the shallowest occurrence of groundwater within the Permit 

Area, although the horizon is not saturated in all portions of the Permit Area. The 

depth to groundwater in the DE horizon has been measured from approximately 

155 feet to 257 feet below ground surface; however some of the monitor wells 

were occasionally dry during the monitoring events. The DE Horizon consists of a 

sequence of sands and discontinuous clay/shale units. In the southern portion of 

the Permit Area, sands of the DE Horizon coalesce with sands of the FG Horizon. 

The top of the unit ranges from 100 to 200 ft bgs (Figure 3.3-3).

FG Horizon 

The top of the FG Horizon occurs at depths of approximately 250 to 300 ft bgs on 

the north side of the Fault and 275 to 350 ft bgs on the south side of the Fault 

within the Permit Area. The FG Horizon is subdivided into the Upper (UFG), 

Middle (MFG) and Lower (LFG) Sands (Figure 3.3-3). The total thickness of the 

FG Horizon is approximately 100 feet. The basal unit in the FG Horizon, the 

LFG Sand, ranges from 20 to 50 feet thick within the Permit Area. The LFG 

Sand is designated as the overlying aquifer for the HJ Horizon. 

Lost Creek Shale 

Underlying the FG Sands is the Lost Creek Shale. The Lost Creek Shale appears 

continuous across the Permit Area, ranging from five to 45 feet in thickness. 

Typically, this unit has a thickness of ten to 25 feet. The Lost Creek Shale is the 

confining unit between the overlying aquifer (LFG Sand) and the HJ Horizon 

(Figure 3.3-3). An isopach of the shale thickness is included as Plate D5-2a in 

the WDEQ-LQD Permit to Mine (LCI, 2011b). The confining characteristics of 

the Lost Creek Shale have been demonstrated with a pump test. 

HJ Horizon 

The HJ Horizon is the primary target for uranium production at the Project. For 

purposes of uranium ISR operations, the HJ Horizon has been subdivided into 

three Sands: the Upper HJ (UHJ), Middle HJ (MHJ) and the Lower (LHJ) Sand 

(Figure 3.3-3). These sands are generally composed of coarse-grained arkosic 

sands with thin lenticular intervals of fine sand, mudstone and siltstone. The bulk 

of the uranium mineralization is present in the MHJ Sand. The total thickness of 

the HJ Horizon ranges from 100 to 160 feet, averaging approximately 120 feet. 

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The top of the HJ Horizon ranges from approximately 300 to 450 ft bgs within the 

Permit Area. The three sands are generally separated by thin clayey units that are 

not laterally extensive and, based on pump test results, do not act as confining 

units to prevent groundwater movement vertically between the HJ Sands. The 

underlying aquifer to the HJ Horizon is the UKM Sand. An isopach of the shale 

thickness is included as Plate D5-2b in the WDEQ-LQD Permit to Mine (LCI,

2011b).

Sage Brush Shale 

Beneath the HJ Horizon is the Sage Brush Shale, at depths ranging from 450 to 

550 ft bgs. The Sage Brush Shale is laterally extensive and ranges from five to 75 

feet in thickness (Figure 3.3-3). An isopach of the shale thickness is included as 

Plate D5-2c in the WDEQ-LQD Permit to Mine (LCI, 2011b). The Sage Brush 

Shale is the lower confining unit to the HJ Production Zone. The confining 

characteristics of this unit have been demonstrated through pump tests.

UKM Sand 

The UKM Sand is present beneath the Sage Brush Shale. The UKM Sand is the 

upper member of the KM Horizon and is generally a massive coarse sandstone 

with lenticular fine sandstone intervals. The UKM Sand is the underlying aquifer 

to the HJ Horizon but is also a potential production zone within the Permit Area. 

The UKM Sand is typically 30 to 60 feet thick but can reach over 75 feet in 

thickness (Figure 3.3-3). An isopach of the shale thickness is included as Plate 

D5-2d in the WDEQ-LQD Permit to Mine (LCI, 2011b). The top of the UKM 

Sand is usually between 450 and 600 ft bgs within the Permit Area. 

No Name Shale 

The No Name Shale at the base of the UKM Sand has not yet been fully 

characterized. The top of the unit is approximately 480 to 650 ft bgs. This unit is 

generally 10 to 30 feet thick (Figure 3.3-3).

3.6.2.2 Potentiometric Surfaces 

Potentiometric surfaces for the DE, LFG, HJ, and UKM Horizons in 2008 are 

illustrated as contour maps in Figure 3.6-6 through Figure 3.6-9. Table D6-6 in 

Appendix D6 of the WDEQ-LQD Permit to Mine (LCI, 2011b) lists static water 

level data recorded in 1982, 2006, 2007, and 2008. Based on the potentiometric 

surface maps, groundwater flow is to the west-southwest within the Permit Area, 

generally consistent with the regional flow system. 

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Based on the water level data collected for the HJ Horizon in the vicinity of the 

Fault, it is evident that the Fault provides a significant hydraulic barrier to 

groundwater flow. The potentiometric surface on the north side of the Fault is 5

to 15 feet higher than on the south side. The difference in hydraulic head across 

the Fault becomes less to the northeast. HJ Horizon water level data from 1982 

and 2006 are shown on Figure 3.6-10. There are an insufficient number of data 

points to accurately represent the potentiometric surface for both those 

measurement periods. However, the data illustrate the difference in water levels 

within the HJ Horizon across the Fault. 

The steep gradient observed in the potentiometric surface from the north to the 

south side of the Fault is most likely a manifestation of a lower permeability 

transition area associated with a fault smear zone and/or secondary faulting and 

fracturing near the Fault. This is consistent with regional groundwater flow 

impacted by lower permeability zones studied and modeled by Freeze (1969). 

Although limited groundwater leakage occurs across the Fault (as demonstrated 

during the long-term pump tests), the majority of groundwater flow on both sides 

of the Fault appears to be generally parallel to the Fault, to the west-southwest. 

Based on the potentiometric surface map, groundwater is inferred to flow to the 

west-southwest, generally consistent with the regional flow system. 

The potentiometric surface for the overlying (LFG) aquifer indicates a similar 

groundwater flow direction as in the HJ aquifer, towards the west-southwest 

(Figure 3.6-7). The barrier effect of the Fault is also evident within this 

shallower hydrostratigraphic unit, with an observed difference of six to eight feet 

of hydraulic head across the Fault. Potentiometric surface data for the underlying 

(UKM) aquifer also indicate a generally west-southwest direction of groundwater 

flow (Figure 3.6-9). However, the impacts of the Fault are not as evident in this 

hydrostratigraphic unit, with little, if any, difference in hydraulic head across the 

Fault. 

Hydraulic Gradients 

The horizontal hydraulic gradients across the Permit Area were estimated from 

the December 2008 potentiometric surface maps and are summarized in Table 

3.6-3. The gradients are similar in all the aquifers and range from about 0.003 to 

0.007 ft/ft on both sides of the Fault. 

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Table 3.6-3 Horizontal Hydraulic Gradients

Vertical hydraulic gradients were determined in December 2008 by measuring 

water levels in closely grouped wells completed in different hydrostratigraphic 

units, and the results are summarized in Table 3.6-4. Vertical hydraulic gradients 

range from -0.04 to 0.37 ft/ft between the DE, LFG, HJ and UKM aquifers and 

consistently indicate decreasing hydraulic head with depth. The vertical gradients 

indicate the potential for groundwater flow is downward. A downward potential 

is indicative of an area of recharge, as opposed to an upward potential that is 

normally indicative of an area of groundwater discharge. A downward gradient is 

consistent with the structural and stratigraphic location of the Project with regard 

to Great Divide Basin. 

3.6.2.3 Aquifer Testing 

Aquifer properties for the Battle Spring aquifers within the Permit Area have been 

calculated from tests conducted for Conoco in the early 1980s and more extensive 

tests conducted for LCI in 2006, 2007, and 2008. The aquifer characteristics 

calculated from these tests are summarized in Table 3.6-5. The primary purpose 

of the tests conducted prior to 2008 was to determine aquifer characteristics, 

including transmissivity, storativity, hydraulic conductivity, and the potential for 

communication between aquifers. In addition to determining aquifer 

characteristics, the 2008 test collected information specific to operation of MU1, 

including: hydrologic communication between the HJ pumping well and the 

surrounding HJ monitor wells; the influence of the Fault within MU1, and the 

degree of hydrologic communication between the production zone and the 

overlying and underlying aquifers in MU1. Testing similar to that conducted in 

2008 for MU1 would be conducted for each of the other mine units. 

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Table 3.6-4 Vertical Hydraulic Gradients (Page 1 of 4) 

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Table 3.6-4 Vertical Hydraulic Gradients (Page 2 of 4) 

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Table 3.6-4 Vertical Hydraulic Gradients (Page 3 of 4) 

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Table 3.6-4 Vertical Hydraulic Gradients (Page 4 of 4) 

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Table 3.6-5 Summary of Aquifer Characteristics 

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1982 Testing 

In 1982, Hydro-Search, Inc. conducted two 25-hour tests within the HJ Horizon. 

Both pump tests were conducted at a rate of 30 gpm and on the south side of the 

Fault. There was no reported response in the HJ aquifer north of the Fault. 

Monitor wells in the overlying (LFG) and underlying (UKM) aquifers did not 

show any effects from the pump test. The monitor well locations are shown on 

Figure 3.6-4.

2006 Testing 

Hydro-Engineering (2007) conducted several short-term single-well pump tests 

and three longer multi-well pump tests in October 2006. The single-well tests 

ranged from 30 minutes to five hours in duration at rates from 0.67 to 14 gpm. 

The long-term tests were from 20 to 45 hours long at rates of 15 to 19 gpm. Each 

of the long-term tests was conducted in HJ well completions. The monitor well 

locations are shown on Figure 3.6-4. None of the HJ tests indicated significant 

communication (less than 0.2 feet draw down) with the overlying or underlying 

aquifers. The slope inflection point at approximately 150 minutes after the pump 

start indicated that a boundary (the Fault) was encountered and that the Fault is 

generally acting as a barrier to flow. There was also no indication of hydraulic 

communication across the Fault in any of the pump tests. Hydro-Engineering 

concluded that the Fault acts as a hydraulic barrier. 

2007 Testing 

In 2007, Petrotek Engineering Corporation conducted two long-term pump tests 

in the HJ aquifer at Wells LC19M and LC16M, one located on each side of the 

Fault. Pre-pumping monitoring was performed several days in advance of the 

tests to establish baseline conditions and to evaluate barometric effects. HJ 

monitor wells on both sides of the Fault and within distances likely to be impacted 

by the pump tests were included as observation wells. Observation wells in the 

overlying (LFG) and underlying (UKM) aquifers near the pumping wells and 

across the Fault were also monitored during the tests. 

LC19M Test 

The first pump test, with LC19M as the pumping well, was conducted to evaluate 

aquifer properties on the north side of the Fault. The locations of the wells 

monitored during the test are shown on Figure 3.6-11. The average pumping rate 

during the test was 42.9 gpm. Maximum drawdown in the pumping well was 

93.3 feet. Monitoring was continued after pump shut-in to record recovery from 

the LC19M test. Drawdown at the end of the test in the HJ aquifer is shown on 

Figure 3.6-12. A detailed discussion of the LC19M test is included in 

Attachment D6-2a of Appendix D6 of the WDEQ-LQD Permit to Mine (LCI, 

2011b). 

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The response of the overlying and underlying aquifers during the pump test was 

small (e.g., on the order of 0.2 to 0.5 feet); but the water level responses did 

correspond to the start and stop of pumping from LC19M in the HJ Horizon. The 

underlying/overlying responses appear to be relatively consistent, regardless of 

distance from the pumping well, the hydrostratigraphic interval monitored, or the 

location relative to the Fault. These water level changes suggest potential impacts 

from off-site pumping or background trends that, because of distance from the 

monitor wells, are manifested at multiple locations at the same or similar times. 

As previously stated, a declining trend in water level elevations was observed 

prior to the start of the test. Most of the wells showed an initial inverted response 

(increase in water level) at the start of the test and then resumed a gradual 

downward trend during the test. This phenomenon was also observed and noted 

by Hydro-Engineering during the 2006 pump tests. It is possible that some of the 

drawdown response could be caused by: 1) pumping in the drilling water well 

(LC1) that is completed in both the DE and FG Horizons; 2) communication 

across multiple sands due to the nature of the Fault distance from the pumping 

well location; 3) communication due to juxtapositioning of hydrostratigraphic 

units across the Fault; or 4) leakage through the confining shale, or any 

combination of these. While LCI has aggressively pursued re-plugging of historic 

wells and continues to do so, it is also possible that some of the communication 

could be related to abandoned wells. 

Responses in observation wells across the Fault were negligible relative to the 

magnitude of drawdown observed in monitor wells located on the same side of 

the Fault as the pumping well. The impact of the Fault on groundwater flow can 

be clearly seen from the responses recorded in a pair of observation wells that 

were placed on either side of the Fault, within 100 feet of each other. Well 

HJT104, located on the north side of the Fault and completed in the HJ Horizon, 

had a maximum drawdown of 40.5 feet at the end of the LC19M test. Well 

HJMP107 (south of the Fault) in the HJ Horizon had a net decrease of 1.4 feet 

from the beginning of the test to the end of pumping at LC19M. At least a portion 

of that change is attributable to a declining trend in water levels that was observed 

in all monitor wells prior to the start of the test. The reason for the background 

trend observed has not been identified; however, it might be a result of offset 

pumping (e.g., LCI’s first two water supply wells that are screened over multiple 

sands). 

LC16M Test 

A second long-term pump test was conducted to evaluate aquifer properties on the 

south side of the Fault. The locations of the wells monitored during the test are 

shown on Figure 3.6-13. The average pumping rate during the test was 37.4 

gpm. Maximum drawdown in the pumping well was 69.3 feet. Monitoring was 

continued after pump shut-in to record recovery from the test. Drawdown near 

the end of the test in the HJ aquifer is shown on Figure 3.6-14. A detailed 

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3.0 AFFECTED ENVIRONMENT

discussion of the LC16M test is included in Attachment D6-2b of Appendix D6 of 

the WDEQ-LQD Permit to Mine (LCI, 2011b). 

As in the LC19M pump test, the response of the overlying and underlying 

aquifers during the LC16M pump test was small (e.g., less than one foot in the 

LFG and less than two feet in the UKM); but the water level responses were 

coincident with the start and stop of pumping from LC16M. The response was 

slightly more pronounced in the UKM and occurred on both sides of the Fault. 

The data from this test appear consistent with the first pump test, showing that the 

Fault, while not impermeable, is a significant barrier to groundwater flow. The 

same wells, located about 100 feet apart and across the Fault from one another 

(HJMP107 and HJT104), that were evaluated during the LC19M test were 

evaluated during the LC16M test. Well HJMP107, located on the same side of 

the Fault as the pumping well, had nearly 25 feet of drawdown near the end of the 

test. Well HJT104, located approximately 100 feet north of Well HJMP107 and 

north of the Fault, had approximately 2.2 feet of drawdown at the end of 

pumping. 

2008 Testing 

Two pump tests were conducted within MU1 due to the faulting that bisects the 

mine unit from west-southwest to east-northeast. The north pump test was 

conducted on the north side of the Fault (and associated splinter fault) in 

November 2008, and the south pump test was conducted on the south side of the 

Fault (and associated splinter fault) in December 2008. Both pump tests were 

conducted in the HJ Horizon, with monitoring of the overlying and underlying 

aquifers as well. The locations of the wells monitored during the 2008 testing are 

shown on Figure 3.6-5. The additional information collected from the two pump 

tests did not significantly alter the information on the aquifer characteristics 

attained from previous pump tests. This information is discussed in detail in 

Attachment MU1 2-1 of the WDEQ-LQD MU1 documents (LCI, 2011b). 

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