5.0 CUMULATIVE IMPACTS
 

5.0 CUMULATIVE IMPACTS 

5.1 Introduction 

NEPA requires an assessment of potential cumulative impacts. Federal 

regulations (40 CFR 1500-1508) define cumulative impacts as: “...the impact on

the environment which results from the incremental impact of the action when 

added to other past, present, and reasonably foreseeable future actions regardless 

of what agency (federal or non-federal) or person undertakes such other actions. 

Cumulative impacts can result from individually minor but collectively significant 

actions taking place over a period of time.”

Potential cumulative impacts for this Project are assessed at the resource level. 

The assessment assumes Project development, operation, groundwater restoration, 

and surface reclamation are conducted in accordance with the provisions of the 

NRC License and the WDEQ-LQD Permit to Mine and assumes successful 

implementation of the environmental protection measures discussed in this EIS, 

as well as compliance with the Rawlins RMP and all other applicable federal, 

state, and local regulations and permit requirements. The analysis of cumulative 

impacts addresses both potential negative and positive impacts and is applicable 

to all alternatives. 

Carbon, Fremont, Natrona, and Sweetwater Counties are experiencing 

considerable natural resource development. Past, present, and reasonably 

foreseeable actions include: 

 Uranium exploration and extraction; 

 Oil and natural gas exploration and extraction; 

 Coal-related development; 

 Wind power generation; and 

 Transmission line construction; 

along with dispersed land use/activities, including: 

 Livestock grazing; 

 Wildlife habitat; and 

 Dispersed recreation (e.g., hunting and camping). 

No projects are currently active or planned within the Permit Area other than the 

Proposed Action; although, several projects are proposed along the eastern margin 

of the Great Divide Basin and adjacent areas. The locations of the projects are 

shown on Figure 5.1-1, and additional information is included in Section 5.1.2. 

While several projects have been identified for the cumulative impacts assessment 

for this EIS, the scale and specifics of the dispersed land use activities listed 

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above could not be identified in all cases and thus their contribution to cumulative 

impacts could not be evaluated. 

5.1.1 Physical and Temporal Limits 

The analyses of the cumulative impacts were based on publicly available 

information on existing and proposed projects, general knowledge of the 

conditions in Wyoming, and reasonably foreseeable changes to existing 

conditions. The physical and temporal limits of the cumulative impact assessment 

for each resource vary depending on the physical extent of the impacts and the 

time frame of the projects generating the impact. 

For the majority of the resources, the appropriate Cumulative Impact Assessment 

Area (CIAA) is the north central portion of the Great Divide Basin, roughly a 10-

mile perimeter around the Permit Area. This CIAA covers an area of about 

200,000 acres. The selection of the north central portion of the Basin was based, 

in part, on a balance between assessment of a large enough area to evaluate an 

aggregate of actions but an area not so large that impacts of the Lost Creek 

Project would be lost among other, larger projects, i.e., the Project impacts could 

be discerned given the potential variability and uncertainty of all other project 

impacts. The Lost Creek Permit Area encompasses about two percent of this 

CIAA, and the projected Project disturbance in the Permit Area is less than one 

percent of the CIAA. 

Another factor in selection of the north central portion of the Great Divide Basin 

as the CIAA for most resources was the physical features that should be taken into 

account; some of which function as physical barriers, which limit the influence of 

potential impacts from projects outside of this CIAA. The regional landscape 

within this CIAA is relatively uniform, consisting of rolling plains with some 

draws, rock outcroppings, ridges, bluffs and some isolated mountainous areas. 

All of the major drainages in the Permit Area are included in this CIAA, and the 

vegetation is primarily sagebrush and rabbitbrush throughout the CIAA. The area 

is sparsely populated, and the closest residence is approximately 15 miles from 

the Permit Area boundary. 

The existence of, and potential for, different types of activities were also taken 

into account in selection of the CIAA. However, within this CIAA, the types of 

activities have been similar over time, with some variability in the level of 

activity. This CIAA also contains the majority of the potential uranium projects, 

which would, if developed, tend to impact resources in a similar manner as the 

Lost Creek Project. Uranium projects located in the north central portion of the 

Great Divide Basin are listed in Table 5.1-1. 

For a few of the resources, however, the north central portion of the Great Divide 

Basin CIAA was not appropriate. For example, air quality impacts must consider 

the impacts on any Class I areas in the vicinity of the Permit Area. Additionally, 

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cumulative impacts on transportation, socioeconomics, environmental justice, 

public and occupational health and waste disposal were assessed at a larger scale, 

based on the counties or communities affected. For example, socioeconomic 

impacts were evaluated over about 100 miles, because of the limited number of 

population centers, all of which are small, in this part of Wyoming. Visual and 

cultural resources were based on the maximum viewshed extent. The CIAAs for 

the individual resources are discussed in more detail in Sections 5.2 through 5.18. 

Section 5.1.2 provides additional information on the historic, current, and planned 

projects in the north central portion of the Great Divide Basin. Historic and 

current disturbance was estimated to cover less than five percent of the CIAA, 

based on the extent of historic disturbance within the Permit Area, the similarity 

in activities throughout the CIAA historically, the natural partial regrowth of 

vegetation over some areas of disturbance, and the reclamation of some 

disturbance, such as the Sweetwater Mine. It was assumed that there would be no 

long-term changes in this part of the Great Divide Basin over the next 20 years, 

with the following exceptions: 

	 the possible restart of the Sweetwater Mill (refitted to process ISR 

materials) sometime within the next 20 years; 

	 for uranium exploration over the next 20 years, the installation (and 

subsequent reclamation) of a total about 500 randomly spaced drill pads, 

each occupying about one acre with associated road, in the areas shown on 

Figure 5.1-1; 

	 for uranium production, the installation (and subsequent reclamation) of a 

total of about 5,000 wells, each occupying an average area of about 0.1 

acres with supporting facilities. The wells would be installed (and 

reclaimed) in successive mine units in two adjacent Lost Creek properties 

over the next 20 years (Figure 5.1-1); and 

	 the use (and subsequent reclamation) of a total of 50 drill pads (each 

occupying about 5 acres with associated roads) for oil and gas 

development over the next 20 years (within 10 miles of the Permit Area). 

Therefore, over the next 20 years, the uranium exploration and extraction would 

result in surface disturbance of about 1,000 acres within the north central portion 

of the Great Divide Basin, and oil and gas exploration would result in surface 

disturbance of about 250 acres in that area. This acreage would be less than one 

percent of the CIAA used for most of the resources. 

The Proposed Action includes continued use of the Plant over the next 20 years 

for other LCI projects, including the deeper KM Horizon in the Lost Creek Permit 

Area and adjacent Lost Creek properties. If another operator develops an ISR 

project in the north central portion of the Great Divide Basin, such as the JABAntelope Project, that operator could potentially request a toll milling 

arrangement with LCI to use the LCI Plant. This would depend on Plant capacity 

and would require revision of both the NRC License and the WDEQ-LQD Permit 

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5.0 CUMULATIVE IMPACTS
 

to Mine, as well as BLM project approval. Most other uranium operators 

interested in projects in this part of Wyoming already have plants established 

elsewhere. Therefore, until the Lost Creek Plant became available for toll 

milling, those operators could be reasonably expected to use their existing plants 

rather than building another new Plant in the north central portion of the Great 

Divide Basin. If the Plant were permitted for use by another ISR operation, that 

would extend the time frame prior to Final Reclamation of the Plant and 

associated facilities, i.e., about 85 acres would remain disturbed beyond the 

anticipated time frame. 

It was also assumed that similar requirements for minimizing operational 

footprints and other environmental protection measures (e.g., using existing roads 

if possible and reseeding with a native seed mix) would be required of all energyrelated operations. 

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5.1.2 Historic, Current, and Planned Projects 

5.1.2.1 Uranium Exploration and Production 

Uranium projects located in the north central portion of the Great Divide Basin 

are listed in Table 5.1-1. Currently, there are no operating uranium mines in the 

southwest part of Wyoming. The projects listed in Table 5.1-1 include those in 

the permitting process for uranium production. The table also lists those projects 

for which permit applications are likely to be submitted and those in exploration, 

for which continued development is speculative. The Sweetwater Project is 

included, because even though the mine is reclaimed, the mill is currently on 

standby. Historic projects are also discussed in this section. 

Table 5.1-1 Current and Planned Uranium Projects – North 

Central Portion of the Great Divide Basin 

Site Name Company/ 

Owner Type County 

Approximate 

Distance from 

Lost Creek 

( miles) 

Direction 

from Lost 

Creek 

Project

 In Permitting Process 

Lost Creek UR-Energy 

Corp. ISR Sweetwater 0 --

 Submittal of Permit Application Reasonably Foreseeable 

Lost Creek 

(deeper KM) 

UR-Energy 

Corp. ISR Sweetwater 0.3 S 

Lost Creek 

(adjacent) 

UR-Energy 

Corp. ISR Sweetwater 0.6 N or E 

Lost Creek 

(adjacent) 

UR-Energy 

Corp. ISR Sweetwater 0.6 S or W

 In Exploration (Submittal of Permit Application Speculative) 

JAB & 

Antelope Uranium One ISR Fremont 13 NNW 

EN UR-Energy 

Corp. ISR Sweetwater 5 ESE 

Toby & ER UR-Energy 

Corp. ISR Sweetwater 6 SE 

North 

Hadsell 

UR-Energy 

Corp. ISR Sweetwater & Fremont 10 NNE 

Arrow UR-Energy 

Corp. ISR Sweetwater 12.5 WNW 

RS UR-Energy 

Corp. ISR Freemont 13 N 

Lost Soldier UR-Energy 

Corp. ISR Sweetwater 14 NE 

On Standby 

Sweetwater 

Mill Kennecott Uranium Mill Sweetwater 1 SSW 

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Uranium Production 

For those projects in the permitting process or those for which permit applications 

are likely to be submitted, the impact assessments include the whole project, 

although time frames can only be estimated as the permitting process is not yet 

complete. Within the next 20 years, LCI is currently planning to develop the 

deeper uranium deposits (the KM Horizon), which underlie the HJ Horizon within 

the current Lost Creek Permit Area, and two adjacent Lost Creek properties. LCI 

plans to use the infrastructure in the Lost Creek Permit Area (e.g., the Plant and 

UIC Class I wells) to the extent possible for those projects. For the purposes of 

the cumulative impacts assessment, it has been assumed that these projects would 

be similar in scale to the Lost Creek Project and that they would be developed 

successively. It should be noted that regulatory approval from NRC and WDEQLQD for developing the deeper deposits and for the adjacent properties must also 

be obtained. 

One source of information on other potential uranium projects are the ‘letters of

intent’ from potential operators to the NRC, which were of critical importance to 

the NRC in the mid-2000s for their planning purposes (e.g., determining 

appropriate staffing levels). However, the letters are subject to change by the 

operators, and many projects have been delayed or put on hold. For example, in 

August 2009, the NRC issued a Notice of Intent to Prepare a Supplemental 

Environmental Impact Statement for the JAB-Antelope project (74 FR 41174, 14 

August 2009). However, in October 2009, Uranium One, Inc. requested deferral 

of the NRC review (Uranium One, Inc., 2010), and the projected submittal date is 

NRC’s 2013 fiscal year (NRC, 2012). As another example, plans to redevelop a

previous ISR project, the Bison Basin Project, about 25 miles northwest of the 

Permit Area, were deferred indefinitely (Wildhorse Energy, 2010). 

Uranium Exploration 

For those projects in exploration it is unclear at this time whether production 

license and permit applications will ever be filed for these properties or what the 

actual scale of the projects would be. Without more specific information on the 

projects, including production horizon and schedule, impact assessment would be 

speculative. Therefore, the impact assessment includes the exploration impacts, 

but not production impacts, for these properties. 

It should be noted that exploration permits may not have been filed with BLM or 

WDEQ for some of these projects because no exploration is planned in the 

immediate future; however, they are included because of general knowledge of 

the projects. 

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Historic Uranium Activities 

Previous uranium exploration drill sites are of the most concern to future projects 

because historic reclamation requirements were limited. In particular, future 

operators expend considerable effort to ensure improperly abandoned drill holes 

from historic exploration (including uranium, oil, and gas) are located to prevent 

interference with mining. Within the Lost Creek Permit Area, LCI has made a 

concerted attempt, including record review, site inspection, and pump tests, to 

find old drill holes and properly abandon them. Some old drill holes have been 

repurposed, although information about the holes may be limited. For example, 

one of the BLM wells near the Permit Area, the Battle Springs Draw Well No. 

4551 (Section 3.6.3.1), was an exploration hole. 

Within 25 miles of the Lost Creek Project, the Sweetwater Project was the only 

historic uranium project brought into production. The Sweetwater Project 

consists of a surface uranium mine and conventional mill. Mining began in the 

early 1980s and ended shortly thereafter due to a decline in uranium prices. 

Reclamation, including a pit lake, was completed in the late 1990s. The mine, 

which targeted a different ore zone than the proposed action, was reclaimed in 

accordance with WDEQ-LQD requirements. The mill, which is under NRC 

jurisdiction, was put on standby in the event uranium production became 

economical again. Leakage from the original tailings impoundment resulted in 

creation of a shallow, contaminated water table aquifer, which is under corrective 

action per NRC requirements. Eventually, the mill tailings area must be turned 

over to the State or DOE for long-term care in accordance with the requirements 

of the Uranium Mill Tailings Radiation Control Act (UMTRCA). Because of the 

different ore depths and mining and ore processing methods, the distance between 

the sites, and the mine reclamation, no overlapping impacts are anticipated 

between the Sweetwater and LCI Projects. Also, because LCI is using different 

mining and ore processing methods, none of the Lost Creek Permit Area will 

require long-term care under UMTRCA. 

5.1.2.2 Oil and Natural Gas Exploration and Extraction 

Most of Wyoming’s current oil production is from old oil fields with declining 

production and the level of exploration drilling to discover new fields has been 

low (WSGS, 2002, as cited in BLM, 2008b). Natural gas production, on the other 

hand, has been increasing in Wyoming. The Rawlins RMP summarized oil and 

gas development projects previously or currently subject to NEPA analysis in 

Southwestern Wyoming: 6,469 producing wells and 8,030 wells that can still be 

drilled/produced, encompassing approximately 300,000 acres of land (BLM, 

2008a). Carbon County currently has 47 gas production units (13 active, 34 

inactive), while Sweetwater County currently has 26 gas production units (23 

inactive, 3 active). Three existing and planned oil and gas projects are identified 

in the Project region that have potential to contribute to cumulative impacts 

(Figure 5.1-1). 

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The Lost Soldier-Wertz Oil Fields near Bairoil were discovered in the early 1900s 

and continue to be produced. The closest portion of these fields is located 16 

miles northeast of the Permit Area, and is the primary source for oil and gas 

extraction in the northeast portion of the Great Divide Basin. The oil fields are in 

their final stage of production, under carbon dioxide injection (enhanced oil 

recovery) since 1989. No additional drilling is planned. The Bison Basin Oil 

Field is another old field and is about 25 miles to the west-northwest of the Permit 

Area. These fields are outside the CIAA for most resources, but the fields are 

included for evaluation of impacts to those resources which must be evaluated 

over a larger area, e.g. socioeconomics. 

The most extensive development in the region relates to the Continental Divide 

and Creston Blue Gap gas fields and subsequent infill projects (Figure 5.1-1). 

The development is on the checkerboard pattern of private and federal surface and 

mineral ownership that resulted from historic land grants from the federal 

government for railroad development. One infill project is the Wind Dancer 

Natural Gas Development Project (WDNGDP), which encompasses about 6,400 

acres, 18 miles southwest of the Permit Area. The WDNGDP consists of the 

drilling, completion, and operation of up to 12 natural gas wells and associated 

facilities (access roads, pipelines, utility corridors). The WDNGDP started in 

2004 with an anticipated life of 30 years. Another infill project, the 

approximately 1.1-million-acre Continental Divide – Creston Project involves 

drilling and development of about 9,000 wells with associated facilities (roads, 

pipelines, compressor stations, power system) by numerous companies to further 

develop natural gas resources within the existing Continental Divide and Creston 

Blue Gap natural gas fields. The anticipated duration of the project is 15 years for 

construction and 30 to 40 years of project development and operation. The 

northern boundary of the proposed project is about seven miles south of the 

Permit Area. The BLM published a Scoping Notice in April 2006 (BLM, 2006), 

and work on the Draft EIS is on-going. Even though specifics, such as well 

locations, are not yet known, it was assumed that some of the drilling would be in 

the CIAAs for the Lost Creek Project. 

The Atlantic Rim coal bed methane and natural gas development project covers 

270,080 acres, located approximately 31 miles south of the Permit Area (Figure 

5.1-1). The northern portion of this project is in the checkerboard ownership 

pattern. In March 2007, the BLM published a Record of Decision regarding the 

Final Environmental Impact Statement for this project (BLM, 2007a). Work 

began that year on the 1,800 coal bed methane wells and 200 natural gas wells to 

be drilled over a 20-year period and to be in production for 30 to 50 years. 

Although the Atlantic Rim Project is outside the Lost Creek CIAAs for most 

resources. This project is outside the CIAA for most resources, but the project is 

included for evaluation of impacts to those resources which must be evaluated 

over a larger area, e.g. socioeconomics. 

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Oil and gas leases also exist on properties in the north central portion of the Great 

Divide Basin and adjacent areas, including within the Lost Creek Permit Area 

(Section 3.1.3). An oil and gas lease grants the lessee the “right and privilege to 

drill for, mine, extract, remove, and dispose of all oil and gas deposits” in the 

leased lands, subject to the terms and conditions incorporated in the lease (BLM 

Form 3100-11, Lease for Oil and Gas). The Secretary of the Interior has the 

authority and responsibility to protect the environment within federal oil and gas 

leases, and to accomplish this requirement, restrictions are imposed on the lease 

terms. Therefore, drilling on existing leases would only occur after any proposed 

well locations, road and/or pipeline alignments, and/or other 

facilities/infrastructure have gone through a permitting process and NEPA 

analysis. At present, there are no definitive plans to develop existing leases in the 

eastern north central portion of the Great Divide Basin other than those outlined 

in the previous paragraphs. 

5.1.2.3 Coal-Related Development 

There are no operating surface or underground coal mines or coal gasification 

projects in the north central portion of the Great Divide Basin. The nearest 

planned coal bed methane project is the Atlantic Rim coal bed methane and 

natural gas development project, as discussed in Section 5.1.2.2. A pilot coal bed 

methane project, the Pappy Draw Exploratory Project, was approved by BLM in 

2008 (BLM, 2008b). The proposed location was in the vicinity of the proposed 

JAB and Antelope uranium claims about five miles north of the Permit Area 

(Figure 5.1-1). However, the pilot project was terminated and new approvals 

would be needed for any additional efforts (BLM, 2009a). A pilot underground 

coal gasification project, located about 10 miles west of Rawlins, was conducted 

in the 1990s. No commercial development is planned, and the site is in 

reclamation. 

No coal-related projects are within the CIAA for most of the resources. However, 

the Atlantic Rim Project is included in the CIAA for evaluation of impacts to 

resources which must be evaluated over a larger area, e.g. socioeconomics. 

5.1.2.4 Wind Power Generation 

The nearest wind energy project is the Chokecherry and Sierra Madre Wind 

Energy Project in Carbon County (Figure 5.1-1). It is located 39 miles southsoutheast of the Permit Area. This 1,000-turbine wind farm is proposed by the 

Power Company of Wyoming and construction of the project is anticipated to 

begin in 2012 (Power Company of Wyoming, 2011). The BLM published the 

Draft EIS in July 2011 (BLM, 2011a) and the Final EIS in July 2012 (BLM, 

2012b). This wind project is not within the CIAA for most of the resources. 

However, it is included in the CIAA for evaluation of impacts to resources which 

must be evaluated over a larger area, e.g. socioeconomics. 

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Under the new Greater sage-grouse guidelines developed by the Governor’s SageGrouse Implementation Team (Mead, 2011), no new wind projects would be 

allowed in the core areas for greater sage-grouse breeding and nesting. Much of 

the Great Divide Basin is covered by core areas (Figure 5.1-1). In addition, the 

wind generation potential in the Great Divide Basin is classified as only Fair by 

the Wyoming State Geological Survey (WSGS, 2011) based on information 

developed by the National Renewable Energy Laboratory. Therefore, it is 

unlikely that any other wind energy projects will be developed in the Basin closer 

to the Proposed Action in the foreseeable future. 

5.1.2.5 Transmission Line Projects 

Three large proposed transmission projects of the Project region are the 

TransWest Express Transmission Project, the Gateway West Transmission 

Project, and the Gateway South Transmission Project (Figure 5.1-1). The 

TransWest Express Transmission Project includes a 600-kilovolt direct-current 

transmission system that will extend about 725 miles from south-central 

Wyoming, through northwestern Colorado and central Utah, to southern Nevada. 

The Western Area Power Administration and TransWest Express LLC would be 

joint owners of the extra-high-voltage line designed to carry renewable power 

generated in Wyoming to the Desert Southwest. This project is anticipated to 

begin construction in 2013 (TransWest Express LLC, 2011). The transmission 

line would be as close as about 30 miles directly south of the Permit Area, 

although an alternate route could be closer. 

The Gateway West Transmission Project is a collaborative effort between Idaho 

Power Company and Rocky Mountain Power to construct and operate 230- and 

500-kilovolt transmission lines from Glenrock, Wyoming to Melba, Idaho. This 

project is composed of 11 transmission line segments with a total length of 

approximately 1,000 miles across southern Wyoming and southern Idaho. This 

proposed project crosses approximately 500 miles of public land managed by the 

BLM, including 200 miles in Wyoming. This project is scheduled for line 

segments to be completed in phases between 2014 and 2018 (Idaho Power 

Company and Rocky Mountain Power, 2011). The transmission line would be as 

close as 30 miles south of the Permit Area. 

PacificCorp’s Gateway South Project would add more than 1,900 miles of new 

transmission lines and would be comprised of four segments of high-voltage 

alternating current (AC) transmission lines that would run between existing, 

planned, and proposed substations. The Gateway South Project would follow the 

TransWest Express Transmission Project through Wyoming and Colorado. A 

proposed double-circuit 500kV transmission line or two parallel single-circuit 500 

kilovolt (kV) transmission lines (on the same right-of-way) approximately 350 

miles in length would begin at the planned Aeolus Substation near Medicine Bow, 

Wyoming, continuing southwest near Saratoga, Wyoming, and then continuing 

southwest near Baggs, Wyoming. From the Baggs area, the transmission line 

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would continue into northwestern Colorado in a southwesterly direction towards 

the Utah border near the town of Rangely, Colorado. From that point, the route 

would west-through Utah and Nevada, terminating at the existing Crystal 

Substation near Glendale, Nevada. 

These transmission line projects are outside the CIAA for most of the resources. 

However, they are included in the CIAA for evaluation of impacts to resources 

which must be evaluated over a larger area, e.g. socioeconomics. 

5.2 Cumulative Impacts for Land Use 

The cumulative impacts for land use were assessed within the north central 

portion of the Great Divide Basin, roughly a 10-mile perimeter around the Permit 

Area. The regional landscape within this area is relatively uniform, consisting of 

rolling plains with some draws, rock outcroppings, ridges, bluffs and some 

isolated mountainous areas. Vegetation is primarily sagebrush and rabbitbrush. 

The area is sparsely populated, and the closest residence is approximately 15 

miles from the Permit Area boundary. This area fully encompasses all three 

grazing allotments potentially impacted by the Project. 

Cumulative land use impacts from the energy development projects in the north 

central portion of the Great Divide Basin could impact grazing and hunting and 

recreation access. The projected disturbance would have minimal impact on the 

amount of land available for grazing, but could require changes in fencing, access, 

or other management actions. Environmental protection measures, including 

reclamation requirements, for these projects would reduce the potential for longterm grazing impacts. Recreational and hunting opportunities would also not be 

substantially impacted, but changes in access routes or other management actions 

could impact these land uses. Interference between energy development projects 

would be minimal due to planning requirements for exploration through 

reclamation and the relatively small footprint of the projected activities. 

According to Section 5.2 of the NRC SEIS, the potential future projects (oil, gas, 

coal, and uranium development) could add to the land use impacts from 

construction of new roads and infrastructure that could limit the recreational and 

grazing use of the land. While the impacts associated with the Lost Creek Project 

are expected to be small, the cumulative impacts of past, present and future 

projects could be slightly larger (NRC, 2011a). 

5.3 Cumulative Impacts for Transportation 

Sweetwater, Fremont, Natrona, and Carbon Counties were considered for the 

cumulative effects for transportation because the major transportation routes 

serving the Permit Area pass through these four counties. The cumulative 

impacts for transportation in the north central portion of the Great Divide Basin 

and adjacent areas are minor. If the Sweetwater Mill were restarted for 

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processing ISR materials, the distribution of the transportation impacts would 

probably be similar to that for the Project. During preparation and upgrading of 

the existing mill facilities for new operations, the work force would be larger and 

there would be more deliveries than during actual operations. If another ISR 

project were developed, it is anticipated that the overall traffic volume would be 

less than for the proposed action because another plant would not be built; the ore 

processing would occur at the Lost Creek Plant. The ore-laden fluids from the 

mine unit(s) at the other ISR project could be transported via truck or pipeline, 

depending on distance from the Plant and fluid volumes. 

Exploration activities for uranium, oil, and gas would progress sequentially over a 

multi-year period and would probably occur primarily during the summer and fall, 

so only a limited number of rigs would be active at any one time. While the rig 

crews might commute to Rawlins or other nearby town, the rigs and associated 

vehicles (e.g., water trucks) would probably be left on-site whenever possible. 

Installation of a transmission line in the area would result in a short-term increase 

in traffic as the installation progressed, and the number of commuting vehicles 

would be limited (e.g., five per day). 

Larger projects to the south of the Project, such as the Continental Divide-Creston 

Project will impact transportation primarily because of the scale of the projects. 

One difference is that these larger projects generally use the I-80 corridor and 

roads to the south of the interstate for access. Transportation to and from the 

north central portion of the Great Divide Basin may be more dispersed as 

personnel and equipment travel to the north, toward Casper and Lander, as well as 

along the I-80 corridor and roads north of the interstate. 

Section 5.3 of the NRC SEIS discusses the cumulative impacts to transportation 

in the area. The potential for future projects (oil, gas, coal, and uranium 

development) could add to the impacts from transportation through construction 

of new roads and the increase in traffic associated with the project. The impacts 

associated with the Lost Creek project are expected to be small, with the potential 

to impact smaller towns and roads to a slightly greater extent. The cumulative 

impacts of past, present and future projects could be slightly larger, with a 

moderate impact on the region (NRC, 2011a). 

5.4 Cumulative Impacts for Geology 

The cumulative impacts for mineral resources were assessed within the north 

central portion of the Great Divide Basin. This area contains the majority of the 

potential uranium projects, which would, if developed, tend to impact mineral 

resources in a similar manner as the LCI Project. There is no other natural 

resource development project (e.g., oil and gas, coal or coal bed methane) planned 

within the Permit Area in the foreseeable future. Uranium extraction from the 

deeper sand horizon (KM Horizon) within the Permit Area would not generate 

cumulative impact on the geology of the current target sand units. Therefore, no 

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cumulative impact on geology is expected from the proposed action and all of the 

alternatives. 

The cumulative impact on geologic hazards was also assessed to address any 

faults in the area and any potentially impacted receptors. Incremental effects of 

the proposed project on geologic hazards that could potentially occur in the 

Project region are difficult to quantify because of varying site conditions and 

characteristics of different kinds of projects. However, given appropriate design 

or avoidance, the contribution of the proposed project to the cumulative impacts 

on geologic hazards is expected to be minimal, if any. 

Section 5.4 of the NRC SEIS discusses the cumulative impacts from the 

disturbances to the geology of the region. Since the projects are expected to be 

distributed throughout the region, without a significant amount of activity in one 

location, the cumulative impact to the region’s geology is expected to be minimal

(NRC, 2011a). 

5.5 Cumulative Impacts for Soil 

The cumulative impact for soils were assessed within the north central portion of 

the Great Divide Basin, as the regional landscape within this area is relatively 

uniform and this area adequately covers the extent of possible cumulative erosion 

and nutrient depletion impacts. The impacts to soil were estimated using the 

assumptions described in Section 5.1 about other activities in the north central 

portion of the Great Divide Basin, and assuming similar requirements for 

minimizing operational footprints and other environmental protection measures. 

If the Sweetwater Mill were restarted for processing ISR materials, little, if any, 

additional disturbance beyond the existing footprint would occur. 

Over the next 20 years, the uranium exploration and extraction would result in 

surface disturbance of about 1,000 acres within the north central portion of the 

Great Divide Basin, and oil and gas exploration would result in surface 

disturbance of about 250 acres in that area. Given the similarity of the soils in 

this part of the Basin, this acreage percentage is small, and the disturbance and 

subsequent reclamation would be progressive; therefore, with appropriate 

environmental protection measures, some impacts could be reclaimed before 

others occur and erosion and compaction could be minimized. In particular, 

permitting of any new ISR operations would require Level 1 and Level 3 soils 

surveys, such as those conducted for the Lost Creek Project, to identify specific 

soil types, topsoil stripping depths, and any special protective measures that might 

be necessary for any unique soil type. 

If the Plant were permitted for use by another ISR operation, that would extend 

the time frame prior to Final Reclamation of the Plant and associated facilities, 

i.e., about 85 acres would remain disturbed beyond the anticipated time frame. 

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Adding a dryer circuit to the Plant is not expected to increase the area of 

disturbance generated from the current proposed action. 

Soils impacts for the other energy development projects in the north central 

portion of the Great Divide Basin could include compaction and erosion of soil 

due to two-track roads, well pad construction, and activities similar to those for 

the Lost Creek Project. Environmental protection measures, including 

reclamation requirements, for these projects would reduce the potential for longterm soils impacts, such as those that resulted from previous exploration and 

development activities. 

Section 5.4 of the NRC SEIS discusses the cumulative impacts from the 

disturbances to the soil of the region. Since the projects are expected to be 

distributed throughout the region, without a significant amount of activity in one 

location, the cumulative impact to the region’s soils is expected to be minimal.

Localized erosion could become an issue, but with the topography of the land, this 

is expected to be minimal (NRC, 2011a). 

5.6 Cumulative Impacts for Surface Water 

The cumulative impacts for surface water were assessed within the north central 

portion of the Great Divide Basin, as this area contains all the major drainages in 

the Permit Area. Surface water impacts related to the Project are minimal, such 

that even if combined with surface water impacts from other energy-related 

projects within the north central portion of the Great Divide Basin, the impact 

would be negligible. 

Section 5.5.1 of the NRC SEIS discusses the cumulative impacts to the surface 

water in the region, specifically referencing ephemeral streams. Due to the 

temporary nature of these streams, and the proper protection and clean-up efforts 

after leaks and spills enforced in the area, the impacts to surface water would be 

small (NRC, 2011a). 

5.7 Cumulative Impacts for Groundwater 

The cumulative impact for groundwater was assessed within the north central 

portion of the Great Divide Basin. This area is considered adequate for evaluating 

the cumulative impact to groundwater quantity as the maximum estimated extent 

of drawdown from the LCI Project is on the order of three miles outside the 

Permit Area. Potential impacts on groundwater quality would occur on a much 

smaller scale, i.e., within the mine units. Impacts to groundwater from the Project 

include changes to water levels on- and off-site and to groundwater quality onsite. Environmental protection measures and systematic monitoring (Section 

4.7.1 and Section 4.7.2) would be performed at the Project to ensure actual 

changes in water levels and water quality are in line with the anticipated changes, 

and should an excursion occur, it would be readily detected, stopped, and 

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remediated. The water levels are projected to recharge rapidly within the first 

couple of years after groundwater extraction stops and essentially completely 

within 10 to 15 years. In addition, groundwater restoration would allow for the 

same water uses after ISR as before. To alert any future groundwater users or 

others interested in subsurface activities after Reclamation, a deed notice and/or 

physical marker of well locations is required per the WDEQ-LQD NonCoal 

Rules, Chapter 11, Section 8(h) (WDEQ, 2005b). 

If the Sweetwater Mill were restarted for processing ISR materials, the impacts 

during updating and refurbishment of the mill would probably be similar to those 

during Construction of the Project’s surface facilities. In particular, water supply

wells would be needed for dust suppression and employee use. The impacts 

during mill operation are much more difficult to anticipate without more detailed 

information on the mill design and operation. For example, groundwater 

corrective action has been required for the tailings ponds that were used when the 

mill was in production. Therefore, any future mill operations would need to take 

this action into account. 

Drilling of uranium and oil and gas exploration holes would not be anticipated to 

have any groundwater impacts except as a result of a spill or other accidental 

release. Any groundwater pumping for drilling fluid or well testing would be of 

limited duration and quantity compared to the Project. 

If the deeper KM Horizons in the Lost Creek Permit Area or adjacent Lost Creek 

properties are developed, the development would generally be progressive, with 

mine units being brought on-line and then restored in succession. Therefore, the 

cumulative impacts to groundwater levels are expected to be minimal due to the 

water quality restoration requirements and the time lag between the Project and 

the other projects, allowing time for water level recovery. One concern would be 

the cumulative drawdown if the Project’s Mine Unit Production and Restoration

overlapped with that of a new nearby project producing from the same horizon. If 

the mines are producing from the same horizon the drawdowns would be additive 

and can be readily estimated. In addition, each operation would be required to 

conduct water level measurements, so the impacts of the individual operations 

could be differentiated. Water level recoveries after production could also take 

longer if more than one operation in close proximity to another mine were 

underway. With respect to water quality, the same level of baseline monitoring, 

and commitment to operational and post-restoration monitoring, would be 

required to obtain the necessary NRC License and WDEQ Permit to Mine for any 

future ISR operation. It is likely each ISR uranium mine would be required to 

have an aquifer exemption based on current knowledge of the water quality in the 

north central portion of the Great Divide Basin. Even with an exemption, 

WDEQ-LQD requires groundwater restoration after mining so the water would be 

suitable for the same uses as prior to mining. In addition, excursions and leaks 

require timely remediation, so cumulative impacts to groundwater from future 

excursions or leaks are not expected to be significant. 

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One existing, and continuing activity, in the Great Divide Basin for which water 

sources are essential is grazing. Because of the requirements for identification of 

all existing water rights in the vicinity of a proposed ISR operations and 

assessment of any potential impacts from the ISR operation on those rights, there 

should not be any conflicts between development of water resources for grazing 

and for uranium development. One concern that has been identified during the 

Lost Creek baseline data collection effort is the relatively high, naturally 

occurring levels of uranium and radium in groundwater. These elevated levels are 

not necessarily in areas where the uranium ore is sufficiently concentrated for 

mining, but the potential for them to occur should be a factor to consider in citing 

water supply wells for grazing or similar activities. 

Other potential projects in the north central portion of the Great Divide Basin, 

e.g., the Wind Dancer Gas Project, are not dependent on water production from 

shallow aquifers, (e.g., less than 1,000 feet deep) except for water supply for dust 

control or for workers. Other projects may produce poor quality water from 

deeper formations, e.g., on the order of several thousand feet deep, and these 

projects may also have deep disposal wells similar to those in the Lost Creek 

Permit Area. However, permitting of these wells requires identification of the 

injection interval and confining units, permeability and water quality testing, 

monitoring during use, and proper abandonment. Therefore, impacts are isolated 

to the project areas within the Basin. 

Section 5.5.2 of the NRC SEIS discusses the cumulative impacts to groundwater 

in the region, specifically the water usage of past, present and future projects in 

the region. The NRC assumes that the water usage for future projects would be 

similar to the Lost Creek Project, which is a fairly low usage for select purposes. 

The addition of future projects could result in local changes to the groundwater 

level and groundwater quality (though within the same class of use); however, the 

entirety of the Great Divide Basin would be unaffected (NRC, 2011a). 

5.8 Cumulative Impacts for Vegetation 

The cumulative impacts for vegetation were assessed within the north central 

portion of the Great Divide Basin. The regional landscape within this area is 

relatively uniform, supporting primarily sagebrush and rabbit brush vegetative 

communities. Using the assumptions described in Section 5.1 about other 

activities in the area, and assuming requirements for minimizing operational 

footprints and environmental protection would be implemented, the impacts to 

vegetation were evaluated. 

If the Sweetwater Mill were restarted for processing ISR materials, little, if any, 

additional disturbance beyond the existing footprint would occur. Additional 

deep disposal wells might be installed if regulatory approval were obtained. 

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Over the next 20 years, the uranium exploration and extraction would result in 

surface disturbance of about 1,000 acres within the north central portion of the 

Great Divide Basin, and oil and gas exploration would result in surface 

disturbance of about 250 acres of that area. Given the similarity of the vegetation 

cover in this part of the Basin, this acreage percentage is small, and the 

disturbance and subsequent reclamation would be progressive; therefore, with 

appropriate environmental protection measures, some impacts could be reclaimed 

before others occur and erosion, compaction, and vegetation removal could be 

minimized. In particular, permitting of any new ISR operations would require 

vegetation surveys, such as those conducted for the Lost Creek Project, to identify 

specific vegetation types, distribution, any areas of rare or endangered species, 

and any weedy areas. 

If the Plant were permitted for use by another ISR operation, that would extend 

the time frame prior to Final Reclamation of the Plant and associated facilities, 

i.e., about 85 acres would remain disturbed beyond the anticipated time frame. 

Adding a dryer circuit to the Plant is not expected to increase the area of 

disturbance generated from the current proposed action. 

Vegetation impacts for the other energy development projects in the north central 

portion of the Great Divide Basin and adjacent areas could include compaction 

and erosion of top soils due to two-track roads, vegetation and top soil removal 

for well pad and mine unit construction, and activities similar to those for the Lost 

Creek Project. Environmental protection measures, including reclamation 

requirements, for these projects would reduce the potential for long-term 

vegetation impacts, such as the still-visible sites of previous exploration and 

development activities. 

Section 5.6 of the NRC SEIS discusses cumulative impacts to Ecological 

Resources, including vegetation. Present and future resource development in the 

region and livestock grazing activities could lead to changes in the community 

structure in the vegetation or the introduction of invasive species. As more 

projects are added to the region, the impacts are expected to become more severe; 

however, they are not expected to alter ecosystem function (NRC, 2011a). 

5.9 Cumulative Impacts for Wildlife 

The cumulative impacts for wildlife were assessed within the north central portion 

of the Great Divide Basin. This area accounts for potential cumulative impacts on 

less mobile and range wildlife. Using the assumptions described in Section 5.1 

regarding other activities in the area, and assuming requirements for minimizing 

operational footprints and for environmental protection measures would be 

implemented, the impacts to wildlife were estimated. 

Over the next 20 years, the uranium exploration and production would result in 

surface disturbance of about 1,000 acres within the north central portion of the 

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Great Divide Basin, and oil and gas exploration would result in surface 

disturbance of about 250 acres of that area (Section 5.1.1). Given the similarity 

in wildlife habitat in this part of the Basin, this acreage percentage is small, and 

the disturbance is projected to occur over a long time frame; therefore, with 

appropriate environmental protection measures, some impacts could be reclaimed 

before others occur. 

If the Lost Creek Plant were permitted for use by another operation, that would 

extend the time frame prior to Final Reclamation of the Plant and associated 

facilities, i.e., about 85 acres would remain disturbed beyond the anticipated time 

frame. So would the disruptive activities such as delivery trucks in and out of the 

Plant, which could impact wildlife habitat and migration. 

If the Sweetwater Mill were restarted for processing ISR materials, little, if any, 

additional disturbance beyond the existing footprint would occur. Additional 

deep disposal wells might be installed if regulatory approval were obtained. 

These activities could have temporary cumulative impacts to wildlife at the 

Permit Area, in that wildlife displaced from the Permit Area during Construction 

and Operation of the Proposed Action may be also affected by other projects in 

the broader area. However, long-term cumulative effects of the Project are 

expected to be minimal due to the planned revegetation. Ultimately, the disturbed 

areas would be reclaimed to their pre-operational contours and vegetation to 

support the wildlife habitat. Cumulative impacts to specific wildlife, including 

big game, Greater sage-grouse, raptors, and smaller species, are outlined below. 

The CIAA encompasses winter/yearlong range for pronghorn antelope and 

seasonal range for mule deer and elk. Only the most northern portion of the 

CIAA would be within moose range. There is no crucial range within the CIAA. 

Cumulative impacts to big game could result from collisions due to temporary 

increases in traffic in the immediate vicinity of an exploration site and associated 

changes in use patterns. However, impacts such as habitat fragmentation are not 

anticipated because the exploration would not require establishment of a longterm road network but could rely on temporary roads from existing road 

disturbances. In addition, uranium development would be concentrated in 

relatively small areas on the ore zones. 

Almost all of the CIAA, except to the southwest of the Permit Area, is within 

Greater sage-grouse Core Area. The anticipated exploration and development 

would be subject to review under the provisions of the Governor’s Executive

Order for Greater sage-grouse (2011-05) (Mead, 2011). Under such review, the 

projects would be required to demonstrate the project footprint and implement 

measures to minimize potential cumulative impacts, including disturbance area, 

proximity to leks, and timing restrictions, as well as monitoring to determine the 

effectiveness of such measures. While such measures would not completely 

prevent impacts, such as increased mortality from collisions or disturbance due to 

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5.0 CUMULATIVE IMPACTS
 

habitat fragmentation, the intent would be to minimize such impacts. Adaptive 

management provisions would also allow for adjustment of project requirements 

over time as new information becomes available. 

For all projects in the CIAA, timing restrictions for raptor protection would need 

to be implemented, and distance restrictions relative to nest locations would also 

be required. For any mining project, mapping of raptor nests would be required to 

establish baseline conditions. As with big game and Greater sage-grouse, the 

relatively short-term duration of exploration in any given location and 

concentration of mining in the vicinity of the ore zone would reduce the potential 

for long-term cumulative impacts. 

For smaller species, cumulative impacts are anticipated to be greatest for less 

mobile species. Migrating birds and other relatively mobile species that can 

readily move throughout the CIAA would be less subject to habitat disruption, 

although increased collisions are possible. Less mobile species would be 

impacted to a greater degree from direct mortalities and habitat disruption. Postdisturbance reclamation would provide for reestablishment of habitat. 

Section 5.6 of the NRC SEIS discusses cumulative impacts to Ecological 

Resources, including impacts to wildlife. Present and future resource 

development in the region activities could lead to changes in the habitat and 

direct/indirect wildlife fatalities from project activities. As more projects are 

added to the region, the impacts are expected to become more prevalent and 

widespread, but due to the mobility of wildlife, impacts are still expected to be 

small (NRC, 2011a). 

5.10 Cumulative Impacts for Wild Horses 

The cumulative impacts for wild horses were assessed within the north central 

portion of the Great Divide Basin. Using the assumptions described in Section 

5.1 regarding other activities in the area, and assuming requirements for 

minimizing operational footprints and environmental protection measures would 

be implemented, the impacts to wild horses were estimated. 

Over the next 20 years, the uranium exploration and production would result in 

surface disturbance of about 1,000 acres within the north central portion of the 

Great Divide Basin, and oil and gas exploration would result in surface 

disturbance of about 250 acres of that area (Section 5.1.1). Given the similarity 

in wild horse habitat in this part of the Basin, this acreage percentage is small, and 

the disturbance is projected to occur over a long time frame; therefore, with 

appropriate environmental protection measures, some impacts could be reclaimed 

before others occur. 

If the Lost Creek Plant were permitted for use by another operation, that would 

extend the time frame prior to Final Reclamation of the Plant and associated 

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facilities, i.e., about 85 acres would remain disturbed beyond the anticipated time 

frame. The disruptive activities such as delivery trucks in and out of the Plant 

would also be prolonged, which could impact wild horse habitat and migration. 

Additionally, a small acreage would remain fenced to keep out cattle and wild 

horses. Fencing would be constructed according to BLM and WGFD (2004b) 

guidelines to minimize potential mortality or injury to wild horses and wildlife. This 

fencing could have gates with pitless cattle guards, to avoid the entry of horses into 

the fenced areas even if gates were accidentally left open, or automatic gates. 

If the Sweetwater Mill were restarted for processing ISR materials, little, if any, 

additional disturbance beyond the existing footprint would occur. Additional 

deep disposal wells might be installed if regulatory approval were obtained. 

These activities could have temporary cumulative impacts to wild horses at the 

Permit Area, in that wild horses displaced from the Permit Area during 

Construction and Operation of the Proposed Action may be also affected by other 

projects in the broader area. However, long-term cumulative effects of the Project 

are expected to be minimal due to the planned revegetation. Ultimately, the 

disturbed areas would be reclaimed to their pre-operational contours and 

vegetation to support the wild horse habitat. 

5.11 Cumulative Impacts for Air Quality 

The area evaluated for cumulative impacts includes the Permit Area plus 10 miles 

around that area, the north central portion of the Great Divide Basin. The 

evaluation also includes any Class I areas within 100 km of the project boundary. 

This evaluation area was chosen to include areas that are likely to be affected by 

emissions from the proposed project and was chosen to be large enough to 

address concerns by USEPA and other stakeholders regarding impacts related to 

regional ozone formation, visibility in Class I areas, and climate change. The air 

quality impacts from other potential activities within the north central portion of 

the Great Divide Basin are similar to the activities of the Project, including dust, 

emissions from combustion engines, and greenhouse gases; and thus contribute to 

the cumulative impacts on air quality of the region. However, because all the 

production projects would not be developed at the same time, the impact would be 

constant over time, e.g., Lost Creek South would start in succession with Lost 

Creek. Extended operation of the Plant after the current proposed Lost Creek 

Project would generate additional dusts, emissions from combustion engines, and 

greenhouse gases. 

If the Sweetwater Mill were refitted for processing ISR materials, then 

construction related to refitting and upgrading the existing equipment would be 

expected, and the emissions would be similar to those from the Project. Drilling 

of oil and gas exploration holes would be similar to the drilling of the UIC Class I 

wells. Drilling of uranium exploration holes and development of another ISR 

project would be similar to the mine unit drilling. Presuming these activities took 

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place over the next ten years, the cumulative impact would essentially be double 

the impact from the Project. 

Section 5.7 of the NRC SEIS discusses the cumulative impacts on air quality, 

including emissions and fugitive dust. As more projects are developed in the 

area, more emissions and dust would be generated. This would have a moderate 

impact on the local air quality, but only a small impact farther away from the 

present and future project sites (NRC, 2011a). 

5.12	 Cumulative Impacts for Noise 

On-site noise sources would not be audible by off-site receptors; therefore, the 

contribution to cumulative off-site noise impacts would relate to off-site transport 

of materials and yellowcake slurry. Additional traffic resulting from this transport 

is proportionally small compared to the current traffic load, and the current traffic 

load is not expected to increase substantially during the life of the Project. 

Noise generated from the activities considered for the cumulative impacts 

(Section 5.1) are generally similar to those for this Project and are generally 

short-term. Drilling of oil and gas wells would be the potential exception with 

respect to noise level, due to the substantially larger equipment size that is often 

used, but the impacts from such drilling would be short-term. Because of the 

rapid dissipation nature of the noise, unless sources are located very close to each 

other and generating noise at the same time, no cumulative impacts on individual 

receptors are expected. 

Section 5.8 of the NRC SEIS addresses the cumulative impacts to noise in the 

area. The potential impacts are more significant in smaller towns and roads that 

would be affected by increase traffic noise, but impacts to the region are expected 

to be small. Noise generation of future projects would largely depend on the 

increased traffic, and construction and processing equipment used in the future 

projects (NRC, 2011a). 

5.13	 Cumulative Impacts for Historic and Cultural 

Resources 

Cumulative impacts for cultural and historic resources were assessed within a 

radius of about 12 miles of the Permit Area, which is the same extent used for the 

visual resources cumulative evaluation (Section 5.14). Impacts to historic and 

cultural resources are site specific but cumulative. Any disturbance to identified 

historic and cultural sites would result in the reduction of the resource inventory. 

The majority of the lands within the north central portion of the Great Divide 

Basin are managed by the BLM. Therefore, future actions such as uranium or oil 

and gas exploration or development of other ISR operations would require agency 

consultation to determine the level of survey needed and, depending on survey 

results, the need for avoidance or mitigation of sites. 

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Restart of the Sweetwater Mill would not be expected to result in any impacts to 

historic and cultural resources because disturbance of new lands would be limited 

relative to the current size of the property and the prior extent of the associated 

mine permit area. 

Section 5.9 of the NRC SEIS discusses potential cumulative impacts on historical 

and cultural resources of the area. Current development projections in the region 

suggest that the impacts to the cultural resources would be noticeable, i.e., more 

sites may be inadvertently damaged or disturbance to them may need to be 

mitigated. However, the impacts would not completely degrade the cultural 

resources important to the region (NRC, 2011a). 

5.14	 Cumulative Impacts for Visual and Scenic 

Resource 

Cumulative impacts for visual and scenic resources were assessed within a radius 

of about 12 miles of the Permit Area. This distance was chosen as the geographic 

boundary for the analysis of potential cumulative impacts because it represents 

the maximum line of sight (taking into account the curvature of the earth) on a flat 

plain for a structure with a height of about 100 feet above the surroundings 

(Section 5.10 of the NRC SEIS [2011a]). Thus, it takes into account the view 

shed from the Plant, which would be the most visually obvious facility associated 

with the Project. With the exception of the restart of the Sweetwater Mill and 

other ISR operations, all of the impacts would be short-term in the north central 

portion of the Great Divide Basin. For most uranium exploration drilling, the rig 

mast would be the most visible feature from a distance; however, most 

exploration holes generally require only a few days to drill. Rig masts for oil and 

gas drilling are generally taller, the drilling takes longer, and there may be more 

equipment at the drill site. Even so, the impacts would not last more than a 

season. Uranium exploration seldom occurs at night, but oil and gas exploration 

may occur around the clock, which would result in visible lights on the rig masts 

from a distance. However, this is not an uncommon site in many western states. 

Assuming requirements for environmental protection measures would be 

implemented (e.g., infrastructure paint color, reclamation and revegetation) for all 

new drilling activities, the well sites visual impacts would be consistent with the 

VRM Class III and Class IV objectives in the regions. 

The Sweetwater Mill is within a visual inventory Class IV area because the mill 

has impacted the viewshed. No additional buildings are anticipated as part of the 

restart of the Sweetwater Mill, although there could be additional equipment onsite temporarily. 

The Project would increase the number of buildings that are visible while the 

Project is in operation, but the buildings would be removed as part of the 

reclamation. The visual impact of one of the buildings, the Plant, could last 

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several years after the Lost Creek Project if use of the Plant for additional 

development (e.g., Lost Creek South) were approved. However, the Plant would 

be removed eventually, so there would be no residual impact from the Project. 

The Permit Area is within a visual inventory Class III area, as discussed in 

Section 4.14, so the effects of the Project on the visual resources in the area 

would be limited. 

Elsewhere along the northeastern edge of the Great Divide Basin and adjacent 

areas, visual impact depends on the type of project. The Continental Divide –

Creston Project will be operating within the existing Continental Divide and 

Creston Blue Gap natural gas fields. Most of the additional facilities, if not all, 

will be infill structures and thus impacts to visual and scenic resources are 

expected to be insignificant. 

The NRC SEIS discusses cumulative impacts to visual resources in Section 5.10. 

While the Lost Creek project would not significantly impact this resource in the 

long-term, as more energy-related projects such as wind farms are developed in 

the region, the potential for more significant impacts is increased (NRC, 2011a). 

5.15 Cumulative Impacts for Socioeconomics 

The socioeconomic CIAA includes portions of counties near the Permit Area as 

well as communities near the Permit Area. Since the Permit Area is situated in a 

remote area near the corners of four counties, the CIAA includes the northeast 

portion of Sweetwater County, the northwest portion of Carbon County, the 

southeast portion of Fremont County, and (to be inclusive of Casper, where 

employees and contractors may reside) the southern portion of Natrona County. 

The nearby communities include Rawlins, Casper, Bairoil, Jeffrey City, and 

Wamsutter. At the present time, cumulative adverse socioeconomic impacts from 

the Project and other developing projects in the region are anticipated to be 

minimal due to current demographics, economic trends and characteristics, and 

existing infrastructure and services. The start of additional projects would 

increase the number of people in the workforce and thus help the recovery of local 

and regional economy from the economic downturn which began in 2007. 

If the Sweetwater Mill were restarted, it is not anticipated that the workforce 

would be significantly larger than that needed for the Project. If another ISR 

operation started, the workforce would probably be smaller than that for the 

Project, because the Plant at the Project would be used. 

The NRC SEIS (Section 5.11) suggests that the incremental impacts of the Lost 

Creek project would not have a significant impact on the region’s socioeconomic 

resources. The report also discusses that as more workers move to the region for 

future projects, there would be a higher demand for housing, education, and 

health services, but also more employment opportunities and more tax revenues 

(NRC, 2011a). 

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5.16	 Cumulative Impacts for Environmental Justice 

The CIAA evaluated for cumulative environmental justice impacts included 

Sweetwater, and Carbon Counties, as these are the counties in which the largest 

projects near the Proposed Action, e.g., the Continental Divide - Creston Project 

and the Chokecherry - Sierra Madre Wind Energy Projects are located. 

Cumulative environmental justice impacts are not anticipated because of the lack 

of low minority, low-income, and Tribal populations in these counties, as well as 

in the region. 

The NRC SEIS (Section 5.12) also finds that cumulative environmental justice 

impacts are not expected due to the lack of a significant minority or low-income 

population in the region and the lack of activities that would disproportionately 

impact these populations (NRC, 2011a). 

5.17	 Cumulative Impacts for Public and Occupational 

Health 

As long-range health impacts would most likely result from air quality impacts, 

the CIAA used to assess air quality impacts was also used for assessing 

cumulative impacts on public and occupational health. 

5.17.1	 Radiological Impacts 

For a restart of the Sweetwater Mill or development of other ISR operations, 

radiological monitoring programs and protections, similar to those required for 

LCI, would be required. If a proposed uranium project could not demonstrate that 

the potential public exposures at the respective project boundaries were not within 

specified criteria, NRC would not approve the project. For a restart of the 

Sweetwater Mill, upgrades to existing equipment and procedures could be 

required by NRC. The potential impacts of another ISR operation would be less 

than that of the Project, presuming the Plant at the Permit Area would be used for 

processing the ore from the other operation (i.e., another plant would not be built). 

For pipeline installation and other drilling projects, the potential for radiological 

impacts are minimal, similar to those during the Construction phase of the Project. 

During drilling for any resource in most western states, the potential for 

encountering naturally occurring uranium deposits exists. The potential would be 

slightly higher for uranium exploration, as the purpose is to locate ore, but the 

exploration is intended to locate and outline the deposits on widely-spaced 

drilling locations, in contrast to the closely-spaced drilling locations for mine unit 

development once a project is underway. 

Section 5.13 of the NRC SEIS discusses potential cumulative health impacts. 

Radiological impacts are expected to be moderate for workers, however proper 

protection measures, monitoring, and management can reduce this potential. The 

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general public is not expected to be influenced because even with the addition of 

future projects, the exposure is expected to be below the accepted levels (NRC, 

2011a). 

5.17.2 Non-Radiological Impacts 

For a restart of the Sweetwater Mill or development of other ISR operations, 

standard industry health and safety practices and procedures, similar to those 

required for LCI, would be necessary. As noted above, use of the Plant for ore 

processing from another ISR operation would reduce the potential for additional 

non-radiological impacts. For exploration drilling and pipeline installation, 

availability of skilled workers for drilling and excavating helps reduce the 

potential for industrial accidents. As both of these activities are not uncommon in 

this part of Wyoming, and given the current economic conditions, skilled workers 

should be available. 

In Section 5.13 of the NRC SEIS discusses that the workers of current and future 

projects are more likely to be impacted by non-radiological health effects. 

However, due to the management practices, low exposure time, and low 

concentrations, the impacts are not expected to be significant (NRC, 2011a). 

5.18 Cumulative Impacts for Waste Disposal 

The cumulative impacts for waste disposal were assessed on the same scale as the 

socioeconomic resources, as waste disposal may impact the demand of services at 

the community and county level. Waste disposal impacts are generally 

considered as part of the overall socioeconomic impacts (e.g., landfill capacity for 

non-hazardous solid wastes), unless impacts to specific resources are anticipated 

(e.g., potential impacts to water resources from disposal of produced water 

[Section 4.4.3.1 of the Atlantic Rim FEIS (BLM, 2006a)]. However, because of 

the regulatory requirements for disposal of 11(e)(2) byproduct material associated 

with uranium projects, the cumulative impacts for those projects are evaluated 

separately. 

With respect to quantities of waste generated, other than 11(e)(2) byproduct 

material, the quantities of waste from the other ISR operations and the 

Sweetwater Mill (if restarted) are not anticipated to differ significantly from the 

Project. Because the development of those operations would be successive, over 

a 20-year period, waste disposal needs would remain constant over time. If the 

environmental protection and monitoring practices are similar for all the projects, 

the existing waste disposal facilities would have the capacity for all of the other 

potential uranium projects. Given the relative scale of the potential uranium 

projects compared to other energy development projects in the region, and the less 

seasonal/periodic nature of the projects, the relative additional impact of the 

uranium operations is anticipated to be minor. 

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With respect to solid 11(e)(2) byproduct material, the disposal options are more 

limited because of the limited number of facilities licensed to accept such wastes. 

If the Sweetwater Mill, which has a uranium mill tailings impoundment, were 

restarted, it could be a potential disposal site for solid 11(e)(2) materials from the 

Project. As other ISR operations are developed, the amounts of solid 11(e)(2) 

materials are expected to be less than that from the Project, as it is likely the other 

operations would use the Plant for ore processing, if at all possible, rather than 

building another processing facility. Because the majority of the anticipated 

amounts of solid 11(e)(2) byproduct materials come from the decommissioning of 

the Plant and associated facilities, the amount of solid 11(e)(2) byproduct 

materials from each of the other ISR operations could be about one-fourth of the 

estimated amount from the Project. 

With respect to liquid 11(e)(2) byproduct material, the UIC Class I wells at the 

Project could provide for disposal of liquid wastes from other ISR projects, based 

on both the excess capacity of the disposal wells and the fact that the other 

projects would not start at the same time as the Project. If the Sweetwater Mill 

were restarted, the NRC requirements for restarting the mill would presumably 

address upgrading or replacement of the existing tailings impoundment or finding 

a replacement option. Because conventional mill practices have improved, it is 

likely the amount of water used in the mill would be less than that used 

previously. However, without details on the mill operations, it is not clear that the 

UIC Class I wells of the Project would have any capacity for disposal of liquid 

11(e)(2) wastes from the mill. 

Other energy development projects in the Great Divide Basin may also use 

injection wells for disposal of produced fluids (e.g., Section 4.4.3.1 of the Atlantic 

Rim FEIS [BLM 2005]). However, these wells are completed in different 

formations, and permitting requirements include identification of the area of 

influence of the wells and other wells in the vicinity. No other injection wells, 

other than the five permitted by LCI, were identified within the area of influence 

of the LCI wells and in the vicinity (UIC Class I Application, Attachment ADJ-2, 

WDEQ-LQD Permit to Mine [LCI, 2011b]). 

The NRC SEIS (Section 5.14) finds that waste management impacts are expected 

to be minimal. Due to the well-managed waste management in the region and the 

assumption that future projects would adhere to rules and regulations put in place 

for any wastes generated, future projects are not expected to significantly add to 

these impacts (NRC, 2011a). 

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