U.S. Department of the Interior

Bureau of Land Management

Wyoming State Office

Rawlins Field Office June 2004

ENVIRONMENTAL ASSESSMENT for the

Wind Dancer Natural Gas Development

Project, Sweetwater County, Wyoming

U.S. DEPARTMENT OF THE INTERIOR

BUREAU OF LAND MANAGEMENT
MISSION STATEMENT

It is the mission of the Bureau of Land Management to sustain the health, diversity,

and productivity of the public lands for the use and enjoyment of present and future

generations.

BLM/WY/PL-04/027+1310

WYW-030-04-EA-204
United States Department of the Interior

BUREAU OF LAND MANAGEMENT 

Rawlins Field Office 

 P.O. Box 2407 (1300 North Third Street) In Reply Refer To:

 Rawlins, Wyoming 82301-2407 1790

June 23, 2004 

Re: Environmental Assessment for the 

Wind Dancer Natural Gas Development 

Project

Dear Reader: 

This is to inform you of the availability of the Wind Dancer Natural Gas 

Development Project Environmental Assessment (EA) at the Wyoming Bureau of 

Land Management’s (BLM) website: 

www.wy.blm.gov/rfo/nepa.htm

The Wind Dancer Natural Gas Development Project is a natural gas project that 

would explore and develop natural gas resources within the jurisdiction of 

the Rawlins Field Office. In order to satisfy the requirements of the 

National Environmental Policy Act, this EA was prepared to analyze impacts 

associated with the construction, drilling, production, maintenance, and 

reclamation of natural gas wells northwest of Rawlins, Wyoming. 

It is expected that this EA can be viewed at our website beginning June 23, 

2004. This will begin the 30-day public review/comment period for the 

document. We will review all comments and will address substantive comments 

in the Decision Record. A substantive comment is one that would alter 

conclusions drawn from the analysis based on: 1) new information, 2) why or 

how the analysis is flawed, 3) evidence of flawed assumptions, 4) evidence of 

error in data presented, and 5) requests for clarification that bear on 

conclusions presented in the analysis. 

Your comments should be as specific as possible. Comments on the 

alternatives presented and on the adequacy of the impact analysis will be 

accepted by the BLM until July 23, 2004. 

Comments may be submitted via regular mail to: 

Travis Bargsten, Project Manager 

Bureau of Land Management 

Rawlins Field Office 

P.0. Box 2407 

Rawlins, Wyoming 82301 
2

You may also submit comments electronically at the address shown below 

(please refer to the Wind Dancer Natural Gas Development Project): 

e-mail: rawlins_wymail@blm.gov 

Please note that comments, including names, e-mail addresses, and street 

addresses of respondents, will be available for public review and disclosure 

at the above address during regular business hours (7:45 a.m. to 4:30 p.m.) 

Monday through Friday, except holidays. Individual respondents may request 

confidentiality. If you wish to withhold your name, e-mail address, or 

street address from public review or from disclosure under the Freedom of 

Information Act, you must state this plainly at the beginning of your written 

comment. Such requests will be honored to the extent allowed by law. All 

submissions from organizations or businesses, and from individuals 

identifying themselves as representatives or officials of organizations or 

businesses, will be made available for public inspection in their entirety. 

The EA may also be reviewed at the following locations: 

Bureau of Land Management Bureau of Land Management 

Wyoming State Office Rawlins Field Office 

5353 Yellowstone Road 1300 N. Third Street 

Cheyenne, Wyoming 82009 Rawlins, Wyoming 82301 

If you require additional information regarding this project, please contact 

Travis Bargsten, Project Manger, at the Rawlins address or phone 

(307) 328-4387. 

 Sincerely, 

 Field Manager 

Enclosure
Table of Contents 

Acronyms and Abbreviations........................................................................................................ vi 

Chapter 1 - Purpose and Need 

1.0 INTRODUCTION ........................................................................................................... 1-1 

1.1 PROJECT DESCRIPTION AND LOCATION............................................................... 1-1 

1.2 PURPOSE OF AND NEED FOR ACTION.................................................................... 1-3 

 1.2.1 Purpose and Need for the Proposed Development .............................................. 1-3 

 1.2.2 Purpose of the Environmental Analysis Process ................................................. 1-3 

1.3 RELATIONSHIP TO POLICIES, PLANS, AND PROGRAMS.................................... 1-5 

 1.3.1 Conformance with Great Divide Resource Area RMP........................................ 1-5 

 1.3.2 Relationship to Other Plans and Documents ....................................................... 1-5 

 1.3.3 Issues and Concerns............................................................................................. 1-5 

Chapter 2 - Proposed Action and Alternatives 

2.1 PROPOSED ACTION..................................................................................................... 2-1 

 2.1.1 Construction, Drilling, and Completion............................................................... 2-2 

 2.1.1.1 Access Road Construction, Road Use, and Transportation Plan......................... 2-3 

 2.1.1.2 Well Location Construction................................................................................. 2-5 

 2.1.1.3 Drilling Operations .............................................................................................. 2-7 

 2.1.1.4 Completion Operations ........................................................................................ 2-8 

 2.1.1.5 Well Stimulation/Production Testing .................................................................. 2-8 

 2.1.1.6 Production Facilities .......................................................................................... 2-10 

 2.1.1.7 Ancillary Facilities............................................................................................. 2-10 

 2.1.1.8 Pipelines............................................................................................................. 2-10

 2.1.2 Production Operations and Maintenance........................................................... 2-15 

 2.1.2.1 Maintenance....................................................................................................... 2-15

 2.1.2.2 Workovers.......................................................................................................... 2-15

 2.1.2.3 Characteristics of Produced Gas ........................................................................ 2-16 

 2.1.3 Reclamation and Abandonment......................................................................... 2-16 

 2.1.4 Summary and Mitigation Measures................................................................... 2-18 

2.2 NO ACTION ALTERNATIVE..................................................................................... 2-18 

2.3 ALTERNATIVES CONSIDERED BUT NOT ANALYZED IN DETAIL.................. 2-20 

Chapter 3 - Affected Environment 

3.0 INTRODUCTION ........................................................................................................... 3-1 

3.1 GEOLOGY, MINERALS, AND PALEONTOLOGY.................................................... 3-1 

 3.1.1 Geology................................................................................................................ 3-1

 3.1.2 Mineral Resources ............................................................................................... 3-2 

 3.1.3 Geological Hazards.............................................................................................. 3-2 

 3.1.2 Paleontologic Resources ...................................................................................... 3-4 

3.2 CLIMATE AND AIR QUALITY ................................................................................... 3-4 

 3.2.1 Climate and Precipitation..................................................................................... 3-4 

 3.2.2 Air Quality ........................................................................................................... 3-5
Table of Contents 

 ii 

3.3 SOILS .............................................................................................................................. 3-6 

 3.3.1 Soil Types within the WDNGDP Area................................................................ 3-6 

3.4 WATER RESOURCES ................................................................................................... 3-7 

 3.4.1 Surface Water....................................................................................................... 3-7

 3.4.2 Groundwater ....................................................................................................... 3-7 

3.5 VEGETATION, WETLANDS, AND NOXIOUS WEEDS............................................ 3-9 

 3.5.1 Vegetation Cover Types ...................................................................................... 3-9 

 3.5.1.1 Grassland Type ............................................................................ 3-9 

 3.5.1.2 Sagebrush Type............................................................................ 3-9 

 3.5.1.3 Saltbush Type............................................................................. 3-10 

 3.5.1.4 Greasewood Type ...................................................................... 3-10 

 3.5.2 Wetlands and Riparian Areas............................................................................. 3-10 

 3.5.3 Invasive/Noxious Weeds ................................................................................... 3-10 

3.6 RANGE RESOURCES AND OTHER LAND USES................................................... 3-11 

 3.6.1 Range Resources................................................................................................ 3-11 

 3.6.2 Other Land Uses ................................................................................................ 3-11 

3.7 WILDLIFE AND FISHERIES ...................................................................................... 3-11 

 3.7.1 General Wildlife................................................................................................. 3-11 

 3.7.2 Big Game ........................................................................................................... 3-12

 3.7.3 Wild Horse Management ................................................................................... 3-13 

 3.7.4 Upland Game Birds............................................................................................ 3-13 

 3.7.5 Raptors ............................................................................................................... 3-13

3.8 SPECIAL STATUS PLANT, WILDLIFE, AND FISH SPECIES................................ 3-13 

 3.8.1 Threatened, Endangered, Proposed, or Candidate Species................................ 3-13 

 3.8.2 Sensitive Species................................................................................................ 3-14 

 3.8.2.1 Raptors ....................................................................................... 3-16 

 3.8.2.2 Mountain Plover......................................................................... 3-16 

 3.8.2.3 Sage Grouse ............................................................................... 3-16 

 3.8.4 White-Tailed Prairie Dog................................................................................... 3-16 

 3.8.5 Sensitive Plant Species ...................................................................................... 3-16 

3.9 RECREATION .............................................................................................................. 3-17

3.10 VISUAL RESOURCES................................................................................................. 3-17 

3.11 CULTURAL RESOURCES .......................................................................................... 3-17 

 3.11.1 Previous investigations ...................................................................................... 3-18 

 3.11.1.1 Prehistoric .................................................................................. 3-18 

 3.11.1.2 Historic....................................................................................... 3-19 

 3.11.2 Native American Religious Concerns................................................................ 3-19 

 3.11.3 Current Investigations........................................................................................ 3-20 

3.12 SOCIOECONOMICS.................................................................................................... 3-20 

 3.12.1 Population and Demographics ........................................................................... 3-21 

 3.12.2 Economy, Employment, and Housing ............................................................... 3-21 

 3.12.3 Local Government Revenues............................................................................ 3-22 

 3.12.4 Environmental Justice........................................................................................ 3-22 

3.13 TRANSPORTATION.................................................................................................... 3-23 

3.14 HEALTH AND SAFETY.............................................................................................. 3-23 

3.15 NOISE ............................................................................................................................ 3-23 
Table of Contents 

 iii 

Chapter 4 - Analysis of Environmental Consequences 

4.0 INTRODUCTION ........................................................................................................... 4-1 

4.1 GEOLOGY, MINERALS, AND PALEONTOLOGY.................................................... 4-1 

 4.1.1 The Proposed Action............................................................................................ 4-1 

 4.1.2 The No Action Alternative................................................................................... 4-2 

4.2 AIR QUALITY ............................................................................................................. 4-2

 4.2.1 The Proposed Action............................................................................................ 4-2 

 4.2.2 The No Action Alternative................................................................................... 4-3 

4.3 SOILS .............................................................................................................................. 4-4 

 4.3.1 The Proposed Action............................................................................................ 4-4 

 4.3.2 The No Action Alternative................................................................................... 4-5 

4.4 WATER RESOURCES ................................................................................................... 4-5 

 4.4.1 The Proposed Action............................................................................................ 4-5 

 4.4.2 The No Action Alternative................................................................................... 4-6 

4.5 VEGETATION, WETLANDS, AND NOXIOUS WEEDS............................................ 4-6 

 4.5.1 The Proposed Action............................................................................................ 4-6 

 4.5.2 The No Action Alternative................................................................................... 4-6 

4.6 RANGE RESOURCES AND OTHER LAND USES..................................................... 4-7 

 4.6.1 The Proposed Action............................................................................................ 4-7 

 4.6.2 The No Action Alternative................................................................................... 4-7 

4.7 WILDLIFE AND FISHERIES ........................................................................................ 4-7 

 4.7.1 The Proposed Action............................................................................................ 4-7 

 4.7.2 The No Action Alternative................................................................................... 4-8 

4.8 SPECIAL STATUS PLANT, WILDLIFE, AND FISH SPECIES.................................. 4-8 

 4.8.1 The Proposed Action............................................................................................ 4-8 

 4.8.1.1 Federally Listed Species ....................................................................... 4-8 

 4.8.1.2 Sensitive Species................................................................................... 4-8 

 4.8.2 The No Action Alternative................................................................................... 4-9 

4.9 RECREATION .............................................................................................................. 4-11

 4.9.1 The Proposed Action.......................................................................................... 4-11 

 4.9.2 The No Action Alternative................................................................................. 4-11 

4.10 VISUAL RESOURCES................................................................................................. 4-11 

 4.10.1 The Proposed Action.......................................................................................... 4-11 

 4.10.2 The No Action Alternative................................................................................. 4-11 

4.11 CULTURAL RESOURCES .......................................................................................... 4-12 

 4.11.1 The Proposed Action.......................................................................................... 4-12 

 4.11.2 The No Action Alternative................................................................................. 4-12 

4.12 SOCIOECONOMICS.................................................................................................... 4-13 

 4.12.1 The Proposed Action.......................................................................................... 4-13 

4.13 TRANSPORTATION.................................................................................................... 4-14 

 4.13.1 The Proposed Action.......................................................................................... 4-14 

 4.13.2 The No Action Alternative................................................................................. 4-14 

4.14 HEALTH AND SAFETY.............................................................................................. 4-14 

 4.14.1 The Proposed Action.......................................................................................... 4-14 

 4.14.2 The No Action Alternative................................................................................. 4-15 
Table of Contents 

 iv 

4.15 NOISE............................................................................................................................ 4-15 

 4.15.1 The Proposed Action.......................................................................................... 4-15 

 4.15.2 The No Action Alternative................................................................................. 4-15 

4.16 CUMULATIVE IMPACTS.......................................................................................... 4-16 

 4.16.1 Geology, Minerals, and Paleontology ........................................................... 4-17 

 4.16.2 Air Quality..................................................................................................... 4-18 

 4.16.3 Soils............................................................................................................... 4-18

 4.16.4 Water Resources............................................................................................ 4-19 

 4.16.5 Vegetation, Wetlands, and Noxious Weeds .................................................. 4-20 

 4.16.6 Range Resources and Other Land Uses ........................................................ 4-20 

 4.16.7 Wildlife and Fisheries ................................................................................... 4-21 

 4.16.8 Special Status Plant, Wildlife, and Fish Species ........................................... 4-23 

 4.16.9 Recreation...................................................................................................... 4-23 

 4.16.10 Visual Resources ........................................................................................... 4-24 

 4.16.11 Cultural Resources ........................................................................................ 4-24 

 4.16.12 Socioeconomics............................................................................................. 4-25 

 4.16.13 Transportation ............................................................................................... 4-25 

 4.16.14 Health and Safety .......................................................................................... 4-25 

 4.16.15 Noise.............................................................................................................. 4-26

Chapter 5 - Consultation and Coordination 

5.0 Consultation and Coordination ........................................................................................ 5-1 

5.1 Public Participation.......................................................................................................... 5-1 

5.1 List of Preparers............................................................................................................... 5-2 

References...................................................................................................................................R-1

Tables

Table 2.1 Well List, WDNGDP........................................................................................... 2-1 

Table 2.2 Proposed Reclamation Seed Mix....................................................................... 2-17 

Table 2.3 Disturbance Summary, Proposed Action........................................................... 2-19 

Table 3.1 Critical Elements of the Human Environment, WDNGDP ................................. 3-1 

Table 3.2 Regional Air Pollutant Background Concentrations and State and Federal

 Ambient Air Quality Standards, WDNGDP........................................................ 3-5 

Table 3.4 STATSGO Soil Information, WDNGDP ............................................................ 3-6 

Table 3.5 Water-Bearing Characteristics of Some Formations, WDNGDP Area............... 3-8 

Table 3.6 Type and Relative Amounts of Vegetation within the WDNGDP Area ............. 3-9 

Table 3.7 Threatened and Endangered Species , WDNGDP Area .................................... 3-13 

Table 3.8 BLM Sensitive Species Potentially Found in Vicinity of WDNGDP ............... 3-14 

Table 3.9 Prehistoric Chronology of the Wyoming Basin................................................. 3-17 

Table 3.10 Population Trends, WDNDGP Project Vicinity ................................................ 3-20 

Table 3.11 Population Ethnicity, WDNDGP Project Vicinity, 2000................................... 3-20 

Table 3.12 Employment by Industry Sector, WDNGDP Vicinity....................................... 3-21 

Table 3.13 County Revenues, Carbon and Sweetwater Counties, 2003.............................. 3-22 

Table 4.1 Near-Field Ambient Air Quality Impacts (μg/m3

)............................................... 4-3 
Table of Contents 

 v 

Table 4.2 Near-Field Increment Comparison(μg/m3

) .......................................................... 4-3 

Table 4.3 WDNGDP Estimated Government Revenues, Life of Project ..........................4-13 

Table 4.4 Existing Oil and Gas Fields Near the WDNGDP .............................................. 4-16 

Table 4.5 Potential Oil and Gas Development Projects, Great Divide Basin....................4-17 

Table 4.6 Areas of Influence Used for Cumulative Impacts Analysis............................... 4-21 

Figures

Figure 1.1 Location of the Wind Dancer Unit in South Central Wyoming .......................... 1-2 

Figure 2.1 Typical Roadway Construction Plans.................................................................. 2-4 

Figure 2.2 Typical Drilling Well Location Layout ............................................................... 2-6 

Figure 2.3 Wellbore Diagram................................................................................................ 2-9 

Figure 2.4 Typical Producing Well Location Layout.......................................................... 2-11 

Figure 2.5 Typical Pipeline Installation .............................................................................. 2-13 

Figure 2.6 Mountain Gas Resources Proposed 8 Inch Gas Pipeline................................... 2-14 

Figure 3.1 Stratigraphic Column, WDNGDP Area.............................................................. 3-3 

Figure 4.1 Raptor Nest and Sage Grouse Lek Locations, Project Area .............................. 4-10 
Table of Contents 

 vi 

ACRONYMS AND ABBREVIATIONS 

Ac-ft Acre Feet 

AOI Area of Influence 

APD Applications for Permit to Drill 

AQRV Air Quality Related Values 

AUM Animal Unit Month 

bbls barrels 

BCFE billion cubic feet equivalent 

bcf billion cubic feet 

BLM U.S. Bureau of Land Management 

BOP blowout preventer 

BCPD barrels condensate per day 

BWPD barrels water per day 

CAA Clean Air Act 

CBNG coalbed natural gas 

CEQ Council for Environmental Quality 

CFR Code of Federal Regulations 

COA Conditions of Approval 

CRO State Historic Preservation Office Cultural Records Office 

CWA Clean Water Act (Federal Water Pollution Control Act) 

dBA A-weighted decibels 

DOT U.S. Department of Transportation 

EA Environmental Assessment 

EIS Environmental Impact Statement 

EPA U.S. Environmental Protection Agency 

FEIS Final Environmental Impact Statement 

FLPMA Federal Land Policy and Management Act of 1976 

FONSI Finding of No Significant Impact 

FOOGRA Federal Onshore Oil and Gas Leasing Reform Act 

ft feet 

gpm gallons per minute 

HAP hazardous air pollutants 

HMA Horse Management Area 

ID Team Interdisciplinary Team 

LOP Life of Project 

MCFD thousand cubic feet per day 

mg/l milligrams per liter 

mi mile 

MMCFD million cubic feet per day 

mmhos millimhos 

mpg miles per hour 

NAAQS National Ambient Air Quality Standards 

NEPA National Environmental Policy Act 

NOI Notice of Intent 

NOX nitrogen oxides 
Table of Contents 

 vii 

NPDES National Pollutant Discharge Elimination System 

NRCS Natural Resource Conservation Service 

NWI National Wetlands Inventory 

O.D. outside diameter 

PFYC Probable Fossil Yield Classification 

PLS Pure Live Seed 

PM10 particulate matter of 10 microns in effective diameter or less 

PM2.5 particulate matter of 2.5 microns in effective diameter or less 

ppm parts per million 

PSD Prevention of Significant Deterioration 

psi pounds per square inch 

psig pounds per square inch gauge 

RCRA Resource Conservation and Recovery Act 

RMP Resource Management Plan 

ROD Record of Decision 

ROW Right-of-Way 

SAR sodium adsorption ratio 

SHPO State Historic Preservation Office 

SPCC Spill Prevention Control and Countermeasure Plan 

STATSGO State Soil Geographic Database 

SUP Surface Use Plan 

SWPP Stormwater Pollution Prevention Plan 

TDS total dissolved solids 

TES Threatened or Endangered Species 

TSP total suspended particulates 

USFWS U.S. Fish and Wildlife Service 

VOC volatile organic compounds 

VRM Visual Resource Management 

WAAQS Wyoming Ambient Air Quality Standards 

WDAI Wyoming Department of Administration and Information 

WDEQ Wyoming Department of Environmental Quality 

WDNGDP Wind Dancer Natural Gas Development Project 

WDOE Wyoming Department of Employment 

WDU Wind Dancer Federal Exploratory Unit 

WGF Wyoming Game and Fish Department 

WSEO Wyoming State Engineer's Office 
 1-1 

CHAPTER 1 - PURPOSE AND NEED 

1.0 INTRODUCTION 

GMT Energy Corp. (GMT) as unit operator (Operator) and its agent operator Cabot Oil & Gas 

Corporation (Cabot), both of Denver, Colorado notified the Bureau of Land Management 

(BLM), Rawlins Field Office, that the company proposes to explore and develop natural gas 

resources within the Wind Dancer (Federal Exploratory) Unit (WDU) located in the Great 

Divide Basin of south central Wyoming (Figure 1-1). Reference in this document to GMT will 

include Cabot as well. The Bureau of Land Management is preparing this Environmental 

Analysis (EA) for the proposed natural gas project which is known as the Wind Dancer Natural 

Gas Development Project (WDNGDP). 

1.1 PROJECT DESCRIPTION AND LOCATION 

This project consists of the construction of up to twelve additional well locations located in the 

WDNGDP. One or more wellbores may be drilled from each well location (such as to different 

target depths). Five exploratory wells have been drilled and completed within the WDNGDP, 

and one replacement well, which is a “twin well” on an existing wellpad, is in the initial 

construction phase. (See Well Location List in Chapter 2, Table 2.1). Initial drilling operations 

for the twelve new well locations are proposed to begin in July of 2004. Drilling at the twelve 

well locations is anticipated to take 6 months to 1 year, with the total life of the project (LOP) 

estimated at 10 to 30 years. The proposed WDNGDP Project Area has some limited existing 

infrastructure (e.g. access roads and natural gas gathering lines) available for support of the 

proposed activity. 

The WDNGDP is located in Township 24 North, Range 96 West, Sweetwater County, 

Wyoming, and is located approximately 30 miles north of Wamsutter and approximately 45 

miles northwest of Rawlins. Access to the WDNGDP is provided by several Sweetwater County 

Roads, including the Tipton Road County #4-67 north from Interstate 80 (I-80) west of 

Wamsutter Wyoming. The Project occurs within the administrative boundary of the BLM’s 

Rawlins Field Office

The WDNGDP Project Area encompasses approximately 6,400 acres. Ownership of all of the 

surface and minerals is by the federal government. 

Chapter 1 - Purpose and Need 

 1-3 

1.2 PURPOSE OF AND NEED FOR ACTION 

1.2.1 Purpose and Need for the Proposed Development 

Exploration and development of federal oil and gas leases by private industry is an integral part 

of the BLM’s oil and gas leasing program under authority of the Mineral Leasing Act of 1920, as 

amended, the Mining and Minerals Policy Act of 1970, the Federal Land Policy and 

Management Act of 1976, the National Materials and Minerals Policy, Research and 

Development Act of 1980, and the Federal Onshore Oil and Gas Leasing Reform Act of 1987. 

The purpose of the proposed WDNGDP is to exercise the lease holders’ rights within the project 

area to drill for, extract, remove, and market gas products. Federal mineral leasing policies and 

the regulations by which they are enforced recognize the statutory right of lease holders to 

develop federal mineral resources to meet continuing national needs and economic demands so 

long as undue and unnecessary environmental degradation is not incurred. 

Also included is the right of the lease holders within the Project Area to build and maintain 

necessary improvements, subject to renewal or extension of the lease or leases in accordance 

with the appropriate authority. The proposed project would allow the Operator to determine, 

through exploration and production of natural gas, if larger scale development is feasible. 

1.2.2 Purpose of the Environmental Analysis Process 

The purpose of this EA is to provide the decision-makers with information needed to make a 

decision that is fully informed and based on factors relevant to the proposal. It also documents 

analyses conducted on the proposal and alternatives in order to identify environmental impacts 

and mitigation measures necessary to address issues. The EA also provides a vehicle for public 

review and comment on the Operator's proposal, the environmental analysis, and conclusions 

about the relevant issues. 

This EA has been prepared to evaluate and disclose the potential environmental impacts 

associated with the proposed natural gas project. The proposed project would occur on BLM 

lands managed by the Rawlins Field Office as shown on Figure 1-2.

Factors considered during the environmental analysis process regarding the WDNGDP include 

the following: 

x A determination of whether the proposal and alternative are in conformance with the 

policies, regulations, and approved resource management plan for the BLM and other 

agencies.

Chapter 1 - Purpose and Need 

 1-5 

x The location of environmentally-suitable well locations, access roads, pipelines, and 

production facilities that are compatible with other resource activities and that minimize 

surface resource impacts yet honor the lease rights within the Project Area. 

x The determination of impacts resulting from the Proposed Action and alternatives on the 

human environment, if conducted in accordance with applicable regulations and lease 

stipulations, and the development of mitigation measures necessary to avoid or minimize 

these impacts. 

1.3 RELATIONSHIP TO POLICIES, PLANS, AND PROGRAMS 

This EA is prepared in accordance with the National Environmental Policy Act (NEPA) and is in 

compliance with all applicable regulations and laws passed subsequent to the act. This EA 

assesses the environmental impacts of the Proposed Action and No Action alternatives and 

serves to guide the decision-making process. 

1.3.1 Conformance with Great Divide Resource Area RMP 

The BLM’s Great Divide Resource Management Plan (RMP) and Record of Decision (ROD) 

(USDI-BLM 1987, 1988a, 1990) directs the management of BLM-administered lands within the 

Project Area. The objective for management of oil and gas resources as stated in the RMP (pg. 

30) is to provide for leasing, exploration and development of oil and gas while protecting other 

resource values. The ROD found that all public lands in the resource area are suitable for oil and 

gas leasing and development, subject to certain stipulations. 

1.3.2 Relationship to Other Plans and Documents 

The proposed project is in conformance with the State of Wyoming Land Use Plan (Wyoming 

State Land Use Commission 1979) and the Sweetwater County Land Use Plan and would 

comply with all relevant federal, state, and local laws and regulations as indicated in Appendix 

A.

The development of this project would not affect the achievement of the Wyoming Standards for 

Healthy Rangelands (August 1977, and as amended). 

1.3.3 Issues and Concerns 

Environmental and social issues of local importance associated with the Operator's WDNGDP 

are identified as follows: 

x Potential impacts to wildlife habitats within the analysis area, primarily nesting raptors 

and sage grouse. 

x Potential impacts to cultural and historical resources within the analysis area. 
Chapter 1 - Purpose and Need 

 1-6 

x Reclamation of disturbed areas and control of non-native plants. 

x Potential impacts to surface water quality. 

x Potential impacts to soil and vegetation within the project area. 

x Potential impacts to groundwater. 

x Cumulative effects of natural gas development activities when combined with other 

ongoing and proposed development activities. 

x Potential conflicts between mineral development activities and recreational activities. 

x Potential impacts to air quality resulting from drilling and production activities. 
 2-1 

CHAPTER 2 - PROPOSED ACTION AND 

ALTERNATIVES

2.1 PROPOSED ACTION 

The Proposed Action would involve the drilling, completion and operation of up to 12 additional 

natural gas well locations by the Wind Dancer Unit (WDU) Operator, GMT Energy Corp. 

(GMT) and/or its partner and agent operator in the WDU, Cabot Oil & Gas Corporation (Cabot). 

A well location would consist of both the short-term and long-term contiguous surface 

disturbance from which one or more wells could be drilled. A well location may have a single 

well drilled from that location, or more than one (such as a twin well drilled to a different 

formation or target depth), but would be restricted to a single, contiguous location where total 

area of the disturbance is minimized. The maximum short-term surface disturbance associated 

with a well pad capable of containing multiple locations would be approximately four acres. The 

actual number of well locations would be determined as development progresses and further 

analysis of the reservoir quality can be made, however the decision record for this EA would 

allow no more than 12 well locations. 

The project is known as the Wind Dancer Natural Gas Development Project (WDNGDP) and the 

project area consists of approximately 6,400 acres. Currently, there are 5 existing producing 

well locations within the project area. If all 12 new well locations are developed, there would be 

a total of 17 well locations in the WDNGDP. Average well location density would be one per 

376 acres upon project completion, if all proposed well locations were to be developed. A listing 

of existing and proposed wells within the Wind Dancer Unit is indicated in Table 2.1.

Table 2.1 Well List, WDNGDP 

Well Location Sec. Twp. Rge. Lease Status

Wind Dancer Unit 40-21 1,184' FSL 1,208' FWL 21 24N 96W WYW132366 Existing 

Wind Dancer Unit 40-28X 1,322' FSL 1,289' FWL 28 24N 96W WYW132367 Existing 

Wind Dancer Unit 40-28 1,315' FSL 1,413' FWL 28 24N 96W WYW132367 Existing 

Wind Dancer Unit 20-29 1,263' FNL 1,359' FEL 29 24N 96W WYW132368 Existing 

Haystack 30-4 1,325 FNL, 1,233 FEL 30 24N 96W WYW125284 Existing 

Wind Dancer Unit #34-20 590' FSL 1,830' FEL 20 24N 96W WYW131838 Proposed 

Wind Dancer Unit #34-21 660' FSL ,980' FEL 21 24N 96W WYW132366 Proposed 

Wind Dancer Unit #12-27 1,981' FNL 561' FWL 27 24N 96W WYW148513 Proposed 

Wind Dancer Unit #14-27 784' FSL 592' FWL 27 24N 96W WYW148513 Proposed 

Wind Dancer Unit 32-28 2,107 FNL, 1947 FEL 28 24N 96W WYW125289 Proposed 

Wind Dancer Unit 34-28 681 FSL, 1,923 FEL 28 24N 96W WYW125289 Proposed 

Wind Dancer Unit #34-29 646' FSL 2,158' FEL 29 24N 96W WYW132368 Proposed 

Wind Dancer Unit #12-29 1,980' FNL 1,120' FWL 29 24N 96W WYW132368 Proposed 

Haystack 11 1,320 FNL, 1,316 FEL 30 24N 96W WYW125284 Proposed 

Wind Dancer Unit #32-32 1,992' FNL 2,145' FEL 32 24N 96W WYW132369 Proposed 
Chapter 2 - Proposed Action and Alternatives 

 2-2 

Well Location Sec. Twp. Rge. Lease Status

Wind Dancer Unit 12-33 1,980 FNL, 660 FWL 33 24N 96W WYW132370 Proposed 

Wind Dancer Unit #32-33 1,980' FNL 1,980' FEL 33 24N 96W WYW132370 Proposed 

The anticipated natural gas production will be from Cretaceous-age sandstone formations. 

Anticipated objective formations are the Lance and Lewis formations, and the Mesaverde Group, 

including the Almond, Ericson and Rock Springs formations. Individual well depths would 

range from 6,000 feet to 13,000 feet depending on the actual objective formation. 

All activities would be conducted according to the regulatory requirements of the BLM and the 

Wyoming Oil and Gas Conservation Commission (WOGCC). The project would begin in the 

summer and fall of 2004 and continue for approximately twelve months, ending in fall, 2005. It 

is estimated that approximately 4.75 miles of additional roads and approximately 4.75miles of 

additional pipelines would be needed to service the well locations. The program would require 

one drilling rig operating continuously. It is possible that a second rig would be added during the 

summer and fall peak drilling periods. The level of activity would be determined by a number of 

factors, some of which are weather, lease wildlife stipulations, drilling rig availability, and 

product price. 

Prior to commencement of drilling for each well, the Operator would file with the BLM and the 

WOGCC an Application for Permit to Drill (APD) containing technical drilling information and 

surface use information. As all acreage consists of federal leases, the drilling plan and surface 

use plan would be in conformance with Federal Oil and Gas Onshore Orders Nos. 1 and 2. 

There are no well location proposals on state or fee mineral ownership. This EA will disclose 

and analyze the site-specific effects of the Proposed Action in detail. Any further necessary sitespecific protection measures or operational requirements for the well could be addressed as 

attached Conditions of Approval (COA) in the APD permitting process. Separate Right-of-Way 

(ROW) permits would be obtained for access roads outside of the WDU. Pipeline easements 

would be filed for under the ROW process as well. The specific requirements and mitigation for 

individual well locations, roads, and/or pipelines are reviewed, discussed and approved within 

these filings. Site-specific environmental analyses may be required for a well location and/or 

portion of pipeline if deviation from the proposed action is required subsequent to a decision for 

this EA. Many of the issues addressed in the individual APD’s and ROW filings are discussed 

below. See Appendix B for a listing of all government agencies with jurisdiction on this project. 

There are no state or fee lands within the WDNGDP area. If access outside of the project area 

were necessary, surface agreements with private surface owner(s) would be completed prior to 

conducting well location, pipeline and road construction. 

2.1.1 Construction, Drilling, and Completion 

The WDNGDP Proposed Project was developed in consultation with the BLM and in 

consideration of comments received during public scoping. The 30 day public scoping period 

ended May 17, 2004. Comments were received from 14 individuals, groups, or government 

agencies. The Proponent and its contractors met with BLM Project Interdisciplinary Team (ID 
Chapter 2 - Proposed Action and Alternatives 

 2-3 

Team) staff March 19, 2004 to review the comments and incorporate suggestions from the 

comments, where warranted, into the EA.

Onsite inspections were conducted for 11 of the 12 proposed wells by BLM ID Team members 

and Proponent's contractors April 19, 2004. Onsite inspection for the Haystack 11 location had 

been conducted in 2002. At that time, the BLM questioned possible flooding issues associated 

with high water in the Hay Reservoir. The reservoir, which had been breached and inactive for 

many years, was recently repaired by the landowner and is again capable of storing water during 

runoff periods. The Operator plans on a modified and elevated well pad and access roads to 

ensure that abnormally high water in the reservoir would not impede access to the well location. 

The Operator has provided a survey that substantiates its claim that the elevation of the Hay 

Reservoir spillway is below the elevation of the proposed well pad (Bargsten, 2004, personal 

communication).

During the onsite inspection, well locations, access roads, and pipeline routes were examined and 

determinations were made as to the necessity of application of COAs during the APD process. 

Modifications to sites were made, as determined necessary by BLM to provide acceptable 

locations for the proposed activities. In addition, numerous mitigative measures have been 

incorporated into the Proposed Action, as indicated in Appendix B. 

2.1.1.1 Access Road Construction, Road Use, and Transportation Plan 

Currently, there are approximately 11.56 miles of roads which service well locations within the 

Project Area, as indicated on Figure 1.2, the Proposed Action. Roads in the WDU are generally 

of two classifications: 1) Local Road (double lane) and 2) Resource Road (single lane). It is 

estimated that an additional 4.75 miles of proposed resource roads would be needed to access 

proposed well locations. The locations of these proposed roads are shown on Figure 1.2. Roads 

would be constructed in accordance with the specifications outlined in the BLM Road Standards 

Manual, Section 9113 and the BLM/USFS Gold Book as shown in cross section on Figure 2.1.

Surface disturbance would generally be less than 40 feet in width, but occasionally surface 

disturbance widths of up to 60 feet could result where unique conditions (such as requirement of 

flat-bottomed ditches) dictate. The typical travel surface would be between 14 and 16 feet wide 

with turnouts as per BLM-9113 as noted above. 

Local contractors would be used for the construction of each road. Two or three people would 

be needed for construction. The length of time to complete each road would vary. A well 

location access road of approximately 1/2 mile would take one or two days depending on 

weather conditions. All roads would be constructed with native materials and maintained to 

provide safe operating conditions at all times as determined by the BLM. Surfacing with gravel, 

scoria, or other approved materials would be used where required by BLM. Brush would be 

removed and windrowed along the road. The topsoil would be windrowed as specified in the 

APD or ROW grant. Some topsoil would be removed from roads and used to reclaim cut slopes 

on permanent roads. 
Figure 2.1 Typical Roadway Construction Plans 

(Source: Surface Operating Standards for Oil and Gas Exploration and Development ("Gold Book"), 1989 
Chapter 2 - Proposed Action and Alternatives 

 2-5 

During the construction, drilling, and completion phases of the Project there would be 

approximately 10 vehicle trips per day to and from the proposed well location, including 50% 

light truck traffic and 50% transport or heavy truck traffic. During the operation, reclamation, 

and maintenance phase of the Project, there would be approximately 1-3 trips per day. Vehicles 

utilized would include pickup trucks for personnel transportation, flatbed semi-trailer trucks for 

transporting construction implements, rig components, tanks, and casing, and other intermediate 

size trucks for activities such as water hauling, well logging and perforating. 

Authorization from the BLM would be obtained prior to any road construction activity through 

the APD and/or ROW process. Other proper authorities would be consulted as necessary. 

Operator would obtain all necessary federal, state, and local permits necessary for conducting 

operations prior to implementation and construction. 

2.1.1.2 Well Location Construction 

The surface disturbance area for each well location, including reserve pit, cut/fill side slopes and 

soil stockpiles, would be up to 4 acres in size. It is anticipated that this size would be required 

for safety during drilling and completion operations (assuming two wellbores drilled from a 

single well location). If only one wellbore were to be drilled from a well location, the 

disturbance area would be approximately 2.7 acres in size. Well location preparation would 

require that vegetation and topsoil be removed. Depending on the site-specific conditions and 

available topsoil in place, 2-12 inches of topsoil would be removed and stockpiled. The amount 

would be determined by the Operator and the BLM at the time of the onsite meeting during the 

APD process. The topsoil would be separated from excess “cut” material and stockpiled for 

future use in reclamation. The well location would be leveled using standard cut-and-fill 

construction techniques and construction machinery. Figure 2.2 shows a typical drilling well 

location layout. 

A reserve pit would be excavated at each well location to temporarily store drilling fluids (mud), 

rock cuttings, and any water which may be produced during drilling. It is estimated that a total 

of 5,000-20,000 cubic yards of material would be excavated with the construction of each well 

location and associated reserve pit. Approximately 15% of excavated material would be topsoil, 

50% would be reserve pit contents, and 35% would be the cut material from the well pad. Where 

considered necessary by the Operator, or at the requirement of the BLM, reserve pits would be 

lined. The liner would be made of synthetic material of sufficient size and qualities to sustain a 

hydraulic conductivity no greater than 1 x 10-7 cm/sec after installation, and which is sufficiently 

reinforced to withstand normal wear and tear associated with the installation and use thereof. 

The liner would be chemically compatible with all substances which would be placed in the pit. 

All reserve pits would be fenced with woven-wire stock fence as typically required by specific 

permit to ensure that wandering wildlife or livestock do not intrude. Netting or flagging would 

be installed over the pit to protect wildlife species, in particular waterfowl, if potentially harmful 

or toxic substances are discharged to the reserve pit. 
Figure 2.2 Typical Drilling Well Location Layout 

Source: GMT Energy Corp.
Chapter 2 - Proposed Action and Alternatives 

 2-7 

2.1.1.3 Drilling Operations 

It is anticipated that the project could be completed using one drilling rig with the possibility that 

a second rig could be added. The rigs would be of sufficient size to be capable of drilling wells 

to a total depth of approximately 12,000 feet. Rigging-up, the preparation of the rig for drilling 

at the site, typically requires 1-3 days and employs approximately 20 people for construction. 

The drilling phase is estimated to take approximately 30 days. During that time there would be 

from 5 to 12 people at the well location, with possibly twice that number during shift changes. 

As many as 4 supervisory people could be residing at the location during various times of the 

drilling phase. This would include the Operator’s representative, wellsite geologist and/or mud 

logger, and drilling contractor’s tool pusher (supervisor), all of whom would reside in trailers 

onsite and located on the well pad. On occasion, some contractors provide a bunkhouse on 

location which would house 8 drilling personnel for several days at a time. This would reduce 

the number of vehicle trips per day by two. 

Sewage disposal facilities require Wyoming Department of Environmental Quality (WDEQ) 

approval. Facilities would be self-contained chemical toilets and waste would be disposed of in 

accordance with state and local regulations. Garbage would be contained in a portable trash cage 

totally enclosed with small mesh wire and would be transported to an authorized disposal facility 

at the completion of operations. 

The drilling rigs are powered by diesel engines. Diesel fuel is supplied to the well location 

during drilling and completion operations by tanker truck, and is stored onsite in tanks during 

operations. Excess diesel fuel is hauled from the site at the end of drilling and completion 

activities. 

Drilling fluids, known as muds, are used to lubricate and cool the drill bit, raise drilled rock 

cuttings to the surface, help protect fresh water zones, and help control underground pressure 

while drilling the well. The muds would consist primarily of fresh water and powdered 

bentonite, a natural clay. Surface drilling would be done with bentonite gel/fresh water. Near 

total depth, a gel-polymer/fresh water system would be used. Muds would be mixed on location 

from dry and liquid components hauled to the rig from nearby towns, and water from the Luman 

water well #2 (SWSW Section 25, T24N, R97W). All drilling mud additives, once used for 

drilling activities, are classified as exempt (non-toxic) under the Resource Conservation and 

Recovery Act (RCRA) guidelines. The specific mud program for each well would be included in 

the APD. 

All drilling programs would include a string of conductor casing (+16 inch diameter) set at a 

depth of 40-80 feet. Surface casing (8-5/8 or 9-5/8 inch diameter) would be set at a minimum 

depth of 1,500 feet and cemented from total depth to surface. Casing setting depths and cement 

programs would be stated in the APD, reviewed and approved on a well-by-well basis, and 

would comply with Onshore Order #2. An 11-inch blowout preventer (BOP), rated at 5,000 

pounds per square inch (psi), would be installed on the surface casing prior to drilling to total 

depth. The BOP would be pressure-tested at installation and at other required intervals per 

Onshore Order #2. 
Chapter 2 - Proposed Action and Alternatives 

 2-8 

2.1.1.4 Completion Operations 

Production casing (41⁄2 or 51⁄2 inch diameter) would be installed from total depth to surface for all 

wells anticipated to produce gas (See well bore diagram, Fig. 2.3). Production casing would not 

be installed in any wells that are determined to be uneconomical. Any well determined to be 

uneconomical would be plugged and abandoned per BLM and/or Wyoming Oil and Gas 

Conservation Commission requirements (See Section 2.1.3 Reclamation and Abandonment, 

below). Casing would be cemented in place by a well cementing service company crew using 

specialized equipment which mixes dry cement and water into a slurry, and which is then 

pumped down the well. During the running-in and cementing of the production casing, an 

additional eight people would be on location. 

Once the production casing is cemented in place, the drilling rig would be moved off the 

location. Completion procedures would then be carried out with a smaller service rig. After 

ensuring that the casing is cleaned out, a cement bond log would be run to evaluate the adequacy 

of the cement. Upon determining that the cement sheath is adequate, the producing formation 

would be perforated. If the sheath were determined to be inadequate, additional cementing 

would be completed. The perforating of the casing and cement sheath would be accomplished by 

a perforating tool assembly, which fires shaped explosive charges. These charges penetrate the 

casing, cement, and producing formation. The holes allow formation fluids (primarily natural 

gas and condensate at Wind Dancer) to enter the wellbore. During completion operations, 3-30 

people would be on location, including service rig crew, perforating and/or other service 

company personnel, and supervisory personnel. 

2.1.1.5 Well Stimulation/Production Testing 

After perforating, the well would be allowed to flow if it were capable of doing so, and the 

produced fluids would be measured or estimated. Typically, because the sandstone producing 

zones at the WDNGDP have low permeabilities, the wells often require fracture stimulation. 

This treatment would be done by pumping fluids (typically polymer-gelled fresh water) down the 

wellbore and into the formation under pressures sufficiently high to fracture the rock formation. 

Sand grains, glass beads, or other similar materials, called proppants, are carried in suspension 

by the fluids into the fractures. These proppants remain when the pumping ceases. The polymer 

is designed to break down within a few hours and the thinned fluid is allowed to flow back to the 

surface at controlled rates. The remaining proppant prevents closure of the induced fractures and 

allows the reservoir fluids to flow more efficiently into the wellbore. Hydrocarbon liquids would 

be separated and stored in steel tanks on location until removed for sale. Fresh water would be 

flowed to a reserve pit during production testing and allowed to evaporate. 

Six or seven people would likely be on location during production testing, but nearly all would 

be commuting to the location except for the testing personnel who are on location 24 hours per 

day. Production testing for WDNGDP wells is anticipated to take 3-15 days. 
 Figure 2.3 Well Bore Diagram

Wing Valve and Choke

Master Valve

Casing Valve

Well Name Wind Dancer # 

Field Wind Dancer

County Sweetwater

State Wyoming

Surface Casing 9 5/8", 40#, J-55 set at 1,500' - C

Production Casing 4 1/2", 11.60#, P-110 or N-80

2 3/8", 6.5#, N-80 tubing

FLOAT COL. 11,957

SHOE 11,999

TD 12,000

Wind Dancer Unit

Typical Lewis/Almond Completion

GMT Energy Corp
Chapter 2 - Proposed Action and Alternatives 

 2-10 

2.1.1.6 Production Facilities 

Once the well has been tested and determined to be economically feasible, it would be equipped 

for production. Tubing would be placed in the well to conduct the flow of gas and liquids to the 

surface. The tubing string also provides a safety measure by causing any deterioration to take 

place on the tubing, which is removable and repairable, instead of the permanent production 

casing. Figure 2.3 shows the tubing string inside the casing. 

A series of valves (the “tree”), designed to regulate the flow of gas and liquids from the well, 

would be installed on top of the wellhead, which is in turn attached to the casing (Figure 2.3). 

Pressure gauges would be installed on the wellhead and tree to monitor casing and tubing 

pressures and maximize well production. 

Once the gas passes through the tree, it is routed to a gas production unit, which is a high 

pressure, separator that isolates the three phases of the well production, 1) natural gas; 2) 

condensate and; 3) water. The natural gas enters a sales pipeline, the liquids flow to tanks. 

Figure 2.4 is a schematic of a productive well location. Condensate would be diverted to 

separate storage tanks for eventual sale. Condensate would be removed by tanker truck. 

Produced water, if any, would be flowed to a tank for eventual transportation to an approved 

water disposal facility (See Part 2.1.2 below regarding disposition of produced water).

In order to maintain aesthetic values, all permanent and semi-permanent facilities would be 

painted Munsell Soil Color Chart “Carlsbad Canyon (2.5Y 6/2)” standard environmental color. 

Firewalls/containment dikes would be constructed and maintained around all storage 

facilities/batteries. The containment structure will have sufficient volume to contain, at a 

minimum, 110% of the entire contents of the largest tank within the facility/battery, per Spill 

Prevention Control and Countermeasure Plan regulations as required under 40 CFR, Part 112. 

2.1.1.7 Ancillary Facilities 

There are currently no compressors or major treatment facilities located in the WDNGDP. 

Based on anticipated production rates, capacity of the existing infrastructure, and current 

production rates, compressors or major treatment facilities may be required for optimum 

production efficiency in the future. The proposed WDNGDP is designed to provide the 

production data necessary to design the field operating systems. No ancillary facilities are 

proposed, however, under the Proposed Action. 

2.1.1.8 Pipelines 

Currently, there are approximately 9.74 miles of pipeline serving the existing wells within the 

WDNGDP as identified on Figure 1.2. It is estimated that an additional 4.75 miles of pipeline 

would be needed to service the additional wells that would be drilled. Several of the locations or 

routes of these pipelines are identified at this time. (Figure 1.2). The main pipeline system 

interconnect to the Red Desert Plant is adequate to handle the anticipated additional production.
Figure 2.4 Typical Producing Well Location Layout 

Source: GMT Energy Corp.
Chapter 2 - Proposed Action and Alternatives 

 2-12 

Authorization for any additional or new pipelines would be applied for separately through the 

BLM ROW application or APD process. 

New natural gas pipelines would become part of the existing gas transportation system owned 

and operated by Mountain Gas Resources, Inc. which is a subsidiary of Western Gas Resources. 

All necessary authorizing actions for natural gas pipelines would be addressed on a case-by-case 

basis. New gas-gathering pipelines would be 6 inches in diameter and the distance from a new 

well to the existing gathering system would average one half mile. The maximum width of the 

pipeline construction ROW and short-term disturbance width would be 50 feet. The ROW 

would be placed adjacent to existing roads and pipelines where possible. Figure 2.5 illustrates 

typical pipeline installation procedures within a 50-foot ROW adjacent to an existing pipeline. 

Following completion of construction, the permanent pipeline ROW would be reduced to a width 

of 30 feet. 

From the proposed gathering pipelines, gas would be transported beyond the Project Area by a 

proposed Mountain Gas Resources pipeline to the existing Hay Reservoir Compressor Station, 

located in NWNE Section 17, T23N, R96W. The proposed pipeline would be an 8 inch 

diameter, steel pipeline with a maximum operating pressure of approximately 1,200 psig. The 

proposed pipeline would extend from the 6 inch gathering pipeline network from a point near the 

Wind Dancer Unit 32-32 proposed well location, SWNE Section 32, T24N, R96W. The pipeline 

would extend in a direction nearly due south to the compressor. Total length of the proposed 8 

inch pipeline would be approximately 2.96 miles. The maximum width of the pipeline 

construction and operational ROW and short-term and long-term disturbance width would be 50 

feet. The ROW would be placed adjacent to an existing road along most of its length. 

Hydrostatic pressure testing would not be conducted. The route of the proposed pipeline is 

illustrated in Figure 2.6. 

Construction methods are specified in the individual Application for Right-of Way, Plan of 

Development. These would be reviewed and approved or modified as agreed to by BLM and 

Western Gas. Construction details, including topsoil stripping, trenching, pipe type and 

installation, backfilling, ripping compacted surface, topsoil replacement and reseeding would be 

considered at this time. Additionally, technical points of pipeline design such as location and 

number of clean-out ports or “pig launchers” and “pig receivers” would be stated, as well as 

pressure test methods and maximum test pressures. Pressure testing would be completed before 

the trenches would be backfilled. Location of pipelines and the clean-out “pig launchers” and 

“pig catchers” would conform to the existing transportation system and would be designed to 

minimize travel off existing roads and/or production locations. It is estimated that well hook-up 

would occur 30-60 days after the well would be completed. 
Full Width ROW Topsoil Salvage

Figure 2.5 Typical Pipeline Installation

Source: Western Gas Resources
Figure 2.6 Mountain Gas Resources Proposed 8 Inch Gas Pipeline 
Chapter 2 - Proposed Action and Alternatives 

 2-15 

Within 12 months of the installation of additional pipelines, the ground would be returned to 

natural contour, and seeded with a seed mix as agreed upon by Western Gas Resources and the 

BLM (see Section 2.1.3 for typical seed mixes). 

2.1.2 Production Operations and Maintenance 

In the vicinity of the WDNGDP, wells produce in a range of 200 thousand cubic feet of gas per 

day (MCFD) to over 5 million cubic feet of gas per day (MMCFD), between 1 and 30 barrels of 

condensate per day (BCPD), and a range of 1 to 30 barrels of water per day (BWPD),. The gas 

would be transported from the well by pipeline, and the condensate would be hauled out by 

tanker truck at such time as approximately 240 barrels were accumulated in the storage tanks. 

Produced water would be managed per Onshore Order #7. All produced water will be 

temporarily stored on-site in tanks, and then trucked in 80-120 barrel quantities to an approved 

disposal facility. 

2.1.2.1 Maintenance 

Routine maintenance of the producing wells would be necessary to maximize performance and 

detect operational difficulties. Company personnel, known as pumpers, would visit each well 

location daily to ensure that operations are proceeding efficiently and safely. This visit would 

include, but would not be limited to, checking gauges, valves, fittings, and on-site water and 

condensate storage. Routine on-site equipment maintenance would also be performed. 

Pipelines would be periodically patrolled and inspected by pipeline personnel on foot or by 

vehicle to check for problems such as erosion, right-of-way condition, unauthorized 

encroachment and any other situations which could cause a safety hazard or require preventive 

maintenance. 

The Operator would be responsible for preventive and corrective road maintenance on all areas 

covered by the ROW grant and approved APD, from the beginning to completion of operations 

and as affected by their operations. On roads under BLM jurisdiction with multiple rights-ofway issued, the Operator will enter into a joint maintenance agreement with all other ROW 

holders. This would include, but not be limited to, snow removal, blading the roadways, 

cleaning ditches and drainage facilities, or other requirements as directed by the Authorized 

Officer. Weed control is by spraying herbicides as necessary. Prior to herbicide application, the 

BLM would be contacted and a Pesticide Use Permit obtained. Where necessary and required by 

BLM, gravel would be placed on roadways. 

2.1.2.2 Workovers 

If a well’s performance is considered by company personnel to be below its potential, the well 

would be subjected to remedial action, known as a "workover", to improve its production. This 

action could entail removing the production tubing from the well, stimulating the formation, 

cleaning obstructing material from the well, or other activity. Workovers for the types of wells 

with an average production rate of less than 5 barrels of water per day (BWPD), would be 

performed with a truck-mounted completion rig. Workovers occur an average of once every 5 
Chapter 2 - Proposed Action and Alternatives 

 2-16 

years. The traffic associated with a workover would be similar to that of a completion. However, 

it takes approximately 10 days for a workover as opposed to 15 days for a completion. Fluids 

generated during workover operations would be handled as indicated above in Section 2.1.1.4, 

Completion Operations and Section 2.1.1.5, Production Testing. 

2.1.2.3 Characteristics of Produced Gas 

The Lance, Lewis, Almond and Ericson gas streams consist predominately of methane gas with 

some heavier hydrocarbon gases. Trace amounts of nitrogen and carbon dioxide are produced. 

Hydrogen sulfide gas (H2S) is not present in the gas streams. 

2.1.3 Reclamation and Abandonment 

The Wyoming State Office has issued the following goal statement with respect to reclamation 

(Instruction Memorandum No. WY-90-231): 

The Wyoming BLM’s primary long-term goal for reclamation is eventual ecosystem 

reconstruction. This means to return the land to a condition approximate or equal to that 

which existed prior to disturbance or to a stable and productive condition compatible with 

that described in the land use plan. Our short-term reclamation goal is to immediately 

stabilize disturbed areas and protect both disturbed and adjacent undisturbed areas from 

unnecessary degradation. 

The Operator intends on complying with BLM’s reclamation policy. After installation of 

production equipment, the producing well location would be reduced from an area of 

approximately 4 acres to an area of approximately 1.5 acres (for a well location with multiple 

wellbores) and from an area of approximately 2.7 acres to an area of approximately 1.5 acres (for 

a well location with a single wellbore). All unneeded, previously disturbed areas would be 

recontoured, then “ripped” 12 inches to 18 inches deep to relieve compaction. Topsoil 

proportionate to the acreage reclaimed and consistent with the site-specific plan approved with 

the APD would be spread over the recontoured portion of the well location and would be 

reseeded within one or two years, subject to weather conditions and time of year of the 

reseeding. The depth of topsoil redistributed would be equivalent to the depth removed at time 

of construction. (See Section 2.1.1.2, Well Location Construction). The remaining topsoil 

stockpile would be stabilized by seeding with a recommended seed mixture and left in place until 

the well location is ultimately reclaimed at the end of its productive life. Reseeding would be 

performed on outside portions of the road disturbance not needed to maintain the road. This 

would be 6 feet or more on both sides of the road. Reseeding would also be performed over the 

entire disturbed area of the pipeline ROW’s, reducing the overall disturbance area. The entire 

well location area and access roads for all unproductive locations would be reclaimed within two 

years, according to BLM requirements. 

Seeding would take place during the spring or fall “seed window” as determined by the BLM, 

subject to weather conditions. Erosion control methods as agreed to by BLM and the Operator 

would be implemented. These could include water bars on contours, water diversion ditches, 
Chapter 2 - Proposed Action and Alternatives 

 2-17 

and other methods as appropriate on a site-specific basis. Compacted soils will be ripped 12 to 

18 inches deep prior to reseeding. 

At the end of the project’s useful life (10-30 years or more), the Operator would obtain any 

necessary authorization from the appropriate regulatory agency to abandon facilities. Orders for 

procedure to plug and abandon the wells and production facilities would be received from the 

BLM. Plugging and abandonment of a well would be consistent with the guidelines and 

regulations of the WOGCC. The gas wells would be permanently plugged, or temporarily shutin until decisions are reached regarding future production options. Upon abandonment, the 

pipelines would be purged of all combustible products and retired in place to avoid unnecessary 

additional disturbance. All above-ground facilities would be removed, and all recontouring and 

reseeding of disturbed land areas (if applicable) would be completed. Abandoned ROWs would 

revert to the appropriate agency control. 

When determining to abandon the facilities authorized by each grant and/or permit, the Operator 

would contact the Authorized Officer to arrange a joint inspection of the ROW and well location. 

The inspection would be held to review implementation of abandonment procedures and the 

reclamation plan. 

All disturbed areas not needed for production which had previously been covered with 

vegetation would be stabilized and revegetated following the drilling phase. Surface areas that 

previously had no vegetation would not be seeded unless it is determined by BLM that removing 

and replacing soil material might improve conditions that would make vegetation growth 

possible.

All disturbed areas will be seeded with the seed mixture indicated in Table 2.2, in quantities 

which would be determined by the BLM and the Operator at the time of the APD or ROW 

application and which would be reviewed at the time of seeding. 

Table 2.2 Proposed Reclamation Seed Mix 

Cited seed rates are for drill seeding, in pounds pure live seed (PLS) For broadcast seeding, double the 

rates indicated. 

Seed will be broadcast or drilled depending on site conditions. Applicant would monitor the 

reseeding on an ongoing basis and replant, if needed. 

Species Scientific Name Variety Pounds

PLS/Acre*

Grasses 

Slender wheatgrass Agropyron techycaulum 2.0 

Thickspike wheatgrass Agropyron dasystachyum Critana 4.0 

Western wheatgrass Agropyron smithii 2.0 

Indian ricegrass Oryzopsis hymenoides 1.0 

Bottlebrush squirreltail Sitanion hystrix 1.0 

Needle-and-thread Stipa comata 1.0 

Shrubs 

Gardner's saltbush Atriplex gardnerii 1.0 

Total 12.0 
Chapter 2 - Proposed Action and Alternatives 

 2-18 

2.1.4 Summary and Mitigation Measures 

Implementation of the Proposed Action would result in short-term and long-term disturbances to 

the surface. Long-term disturbance is that associated with the life of the Project. Short-term 

disturbance would occur during a portion of the Project life, typically prior to commencement of 

the production phase. Short-term disturbance would affect between 87.8 acres (all single well 

locations) and 103.4 acres (all multiple well locations), or 1.4% to 1.6% percent of the Project 

Area, respectively. Well pads represent the largest component of short-term disturbance. 

Interim reclamation would occur after a well is drilled, completed, and pipelines and compressor 

stations are installed. Interim reclamation restores areas not needed for production to their 

original state, or as close as possible. After interim reclamation takes place, the Proposed 

Action's disturbance would be reduced to approximately 61.9 acres, or 1.0% of the Project Area, 

for the long term. 

A summary of short- and long-term disturbance associated with the Project is indicated in Table

2.3.

The results of the scoping process were used to develop alternatives for identified unresolved 

resource conflicts resulting from the Proposed Action. The BLM and the Operator have 

identified appropriate mitigation measures designed to minimize potential impacts from the 

Project. These measures have been incorporated by the Operator into the Proposed Action and 

are indicated in Appendix B.

The proposed facilities locations for the WDNGDP are illustrated in Figure 1.2, Proposed 

Action.

2.2 NO ACTION ALTERNATIVE 

The National Environmental Policy Act (NEPA) requires that a “no action” alternative be 

considered in all environmental documents. For the WDNGDP proposal, the “no action” 

alternative would preclude the oil and gas development described in the Proposed Action within 

the lease and unit areas. The No Action alternative would not, however, preclude the future 

consideration or proposal of additional development. It is likely, furthermore, that the oil and 

gas resources in this area would continue to be developed outside the Unit at their current rate. 

A decision to select this alternative could be supported by one of three findings:
Chapter 2 - Proposed Action and Alternatives 

Table 2.3 Disturbance Summary, Proposed Action  2-19 

Short- Term (Acres) Total Short Term (Acres)) Long-Term (Acres) Total Long-Term (Acres) 

Location Well

Pad

(Single

Locn.)

Well

Pad

(Mult.

Locns.)

Pipeline Access Road Single Well Pad Multi- Well Pad Well Pad (Single Locn.) Well Pad (Mult. Locns.) Pipeline Access Road Single Well Pad Multi- Well Pad

Haystack 11

2.7 4.0 2.7 0.8 6.2 7.5 1.5 1.5 1.6 0.8 3.9 3.9

WDU 34-20

2.7 4.0 2.5 0.8 6.0 7.3 1.5 1.5 1.5 0.8 3.8 3.8

WDU 34-21

2.7 4.0 1.4 0.4 4.5 5.8 1.5 1.5 0.8 0.4 2.7 2.7

WDU 12-27

2.7 4.0 2.6 0.8 6.1 7.4 1.5 1.5 1.6 0.8 3.8 3.8

WDU 14-27

2.7 4.0 2.5 0.7 5.9 7.2 1.5 1.5 1.5 0.7 3.7 3.7

WDU 32-28

2.7 4.0 1.9 0.6 5.1 6.4 1.5 1.5 1.1 0.6 3.2 3.2

WDU 34-28

2.7 4.0 3.1 0.9 6.7 8.0 1.5 1.5 1.8 0.9 4.3 4.3

WDU 12-29

2.7 4.0 3.7 1.1 7.5 8.8 1.5 1.5 2.2 1.1 4.8 4.8

WDU 34-29

2.7 4.0 3.9 1.2 7.7 9.0 1.5 1.5 2.3 1.2 5.0 5.0

WDU 32-32

2.7 4.0 1.3 0.4 4.4 5.7 1.5 1.5 0.8 0.4 2.7 2.7

WDU 12-33

2.7 4.0 0.9 0.3 3.9 5.2 1.5 1.5 0.6 0.3 2.3 2.3

WDU 32-33

2.7 4.0 2.4 0.7 5.8 7.1 1.5 1.5 1.4 0.7 3.6 3.6

MGR 8 in. pipeline

0.0 0.0 18.0 0.0 18.0 18.0 0.0 0.0 18.0 0.0 18.0 18.0

TOTALS 32.4 48.0 46.7 8.6 87.8 103.4 18.0 18.0 35.2 8.6 61.9 61.9
Chapter 2 - Proposed Action and Alternatives 

 2-20 

1) the level or rate of development is no longer in the best interest of the public;

2) endangered or threatened species and/or their habitat would be adversely affected; or

3) the environmental impacts of the proposed action are unacceptable. 

Federal, state, and fee oil and gas leases grant the right and privilege to drill for, mine, extract, 

remove, and dispose of all the oil and gas deposits in the leased lands, subject to the terms and 

conditions incorporated in the lease. The denial of the right to drill could void the lessee’s 

contractual rights. 

2.3 ALTERNATIVES CONSIDERED BUT NOT ANALYZED IN DETAIL 

Some of the issues obtained during the scoping process suggested potential alternatives to the 

Proposed Action. These issues have been examined and a determination has been made that: 

x The suggested alternative is non-viable for reasons indicated, or

x Applicant-committed mitigation measures will eliminate or mitigate the concern. 

Proposed alternatives are required to be technically and economically feasible and to provide the 

opportunity to achieve the Proposed Project (CEQ, Forty Questions, 2a). BLM-mandated 

directional drilling was considered as and alternative. However, it was decided that the geologic 

nature of the target horizons, comprising series of discontinuous, lenticular, low permeability 

sand reservoirs at both shallow and deep stratigraphic levels, rendered directional drilling 

technology technically and economically unfeasible. 

The responses from the public scoping period were considered to identify any unresolved 

resource conflicts. The BLM determined that no unresolved resource conflicts remained, with 

mitigation, that would require analysis of additional alternatives. 
 3-1 

CHAPTER 3 - AFFECTED ENVIRONMENT 

3.0 INTRODUCTION 

Construction of the WDNGDP could potentially affect certain critical elements of the human 

environment, as defined in the BLM Handbook H-1790-1 (NEPA Handbook), Appendix 5, as 

amended. These elements must, at a minimum, be considered in all EAs developed by the BLM. 

The status of the critical elements for the WDNGDP are indicated in Table 3.1.

Table 3.1 Critical Elements of the Human Environment, WDNGDP 

Element N/A or Not 

Present 

Applicable

or Present, 

No Impact 

Discussed 

in EA 

Air Quality X 

Areas of Critical Environmental Concern (ACEC) X 

Cultural Resources X 

Environmental Justice X 

Farm Lands (Prime or Unique) X 

Floodplains X 

Invasive, Non-Native Species X 

Migratory Birds X 

Native American Religious Concerns X 

Threatened or Endangered Species X 

Wastes, Hazardous or Solid X 

Water Quality Drinking/Ground X X 

Wetlands/Riparian Zones X 

Wild and Scenic Rivers X 

Wilderness X 

If the resources or value is not present or is not affected by the Proposed Action, this may be 

documented as a negative declaration. These items will not be discussed further in this EA. In 

addition to the critical elements, this EA discusses the current status and potential environmental 

effects from the Project in the areas of geology, minerals, and paleontology, climate and air 

quality, soils, water resources, vegetation and noxious weeds, range resources, wildlife and 

special status species, recreation, visual resources, cultural resources, socioeconomics, 

transportation, health and safety, and noise.

3.1 GEOLOGY, MINERALS, AND PALEONTOLOGY 

3.1.1 Geology 

The Project Area lies within the Great Divide Basin of southwestern Wyoming. The basin is 

bounded by the Rock Springs Uplift on the southwest, the Wind River Mountains on the north, 

the Rawlins Uplift on the north and east, and the Wamsutter Arch on the south. The current 

structural setting was determined during the Laramide Orogeny (Late Cretaceous-Late Eocene) 

with the creation of the mountain uplifts as sediment sources and the intermontane basins as 

sediment receptors (Mallory, 1972, pgs. 35-44). 
Chapter 3 - Affected Environment 

 3-2 

Surface rocks in the area are comprised of brown sandstones, carbonaceous shales, and coal from 

the Niland Tongue of the Tertiary Wasatch Formation; oil shales, carbonaceous shales, and coal 

from the Luman Tongue of the Tertiary Green River Formation; dunal sands and loess (including 

active and dormant dunes) from the Quaternary period; and clay, silt, and fine sand from playa 

lake and other lacustrine deposits from the Quaternary period. Underlying rocks penetrated by 

drilling are the Tertiary Fort Union Formation, the Upper Cretaceous Lance Formation, the gas 

productive Cretaceous Lewis Formation, and the underlying Cretaceous Mesa Verde Group. The 

latter unit is subdivided in the Project Area into the Almond Formation, Ericson Sandstone, Rock 

Springs Formation, and Blair Formation, in descending order. Virtually all of the subsurface 

rocks are composed of lenticular, discontinuous sand and shale units deposited in fluvial to 

marine marginal environments. 

Rock units below the Upper Cretaceous would not be penetrated by WDNGDP drilling, and they 

are not discussed further in this EA. A stratigraphic column illustrating the Project Area Tertiary 

and Upper Cretaceous rock units is indicated in Figure 3.1.

3.1.2 Mineral Resources 

Mineral resources with proven economic reserves known at this time are limited to gas and 

condensate. All of the Upper Cretaceous units noted above are known to be productive within 

the vicinity of the Project Area. There are currently five producing wells located within the 

Project Area. WOGCC data (WOGCC, 2004, online data) indicate that 61 wells have been 

completed in the Hay Reservoir field which immediately adjoins the Project Area to the west. 

Production at Hay Reservoir is from the Almond, Lance, Lewis and Mesaverde formations, the 

same horizons targeted by the Proposed Action. 

Although underlain by coal-bearing strata, the Project Area is not within an area with coal 

development potential (BLM, 1987, Map 24). Uranium is present north and east of the study 

area, but is not known to exist within the Project Area (BLM, 1987, Map 27). Potentially 

commercial aggregate materials are located in alluvial deposits to the north of the Project Area 

(Harris, 1996) and sodium sulfate deposits have been located in the Lost Creek Lake area 

immediately east of the Project Area (Harris et al., 1985). Oil and gas development does not 

preclude development of other minerals if they should be determined to be economically 

significant in the future. There is no other known economically significant mineral resource in 

the area. 

3.1.3 Geological Hazards 

There are no known significant geological hazards in the Project Area (Case, 1986; Case, 1986a; 

Case, 1997; Case and Boyd, 1987; Case and Green, 2000; Newman, 2004, personal 

communication).
Chapter 3 - Affected Environment 

 3-3 

Figure 3.1 Stratigraphic Column, WDNGDP Area 

Period Formations Project Area 

Production

 

 Green

Wasatch River

Fm. Tipton Tounge 

Fm.

 Niland Tounge 

 

 Luman Tounge 

Tertiary 

Main Body 

Ft. Union Formation 

Lance Fm. 

 Fox Hills Ss. 

 Lewis Sh. 

 

Almond Fm. 

Ericson Ss. 

Rock Springs Fm. 

Upper Cretaceous 

Source: Love and Christiansen, 1985, as modified from McMillen and Winn, 1991 
Chapter 3 - Affected Environment 

 3-4 

3.1.2 Paleontologic Resources 

Surface formations in the Project Area are composed primarily the Niland Tongue of the 

Wasatch Formation and, in the southwest portion of the Project Area, the Luman Tongue of the 

Green River Formation, both of Eocene age (Love and Christiansen, 1985). No significant 

paleontological resources have been identified within the areas of potential disturbance (BLM, 

2003).

The BLM is cooperating with the USFS Rocky Mountain Region and the University of 

Wyoming in an experimental program to classify geological formations according to their 

probability of containing vertebrate fossil resources. The classification system is being 

developed by the Paleontology Center for Excellence. The paleontological classification system 

is designed to provide BLM management with a way to prioritize protection of paleontological 

resources. The program has resulted in the development of the Probable Fossil Yield 

Classification (PFYC) system. The objective of the program is to develop a predictive model 

that will better focus agency management activities and budgets for protection of paleontological 

resources. Under this system, surficial formations are classified on a scale of 1 (lowest) to 5 

(highest) to reflect the likelihood of containing vertebrate fossils. Numeric classifications have 

been developed for both geological formations and individual localities; however, formation 

rankings determine what formations are investigated in detail. Locality or site rankings provide 

an indication of the presence of fossils in exposures of a given formation at a specified site. 

Under the PFYC classification system, both the Wasatch and Green River formations are ranked 

as PFYC Class 5 (Newman, 2004, personal communication). 

3.2 CLIMATE AND AIR QUALITY 

3.2.1 Climate and Precipitation 

The Project Area lies within the Great Divide Air Basin (BLM, 1987, Map 42), in which the 

terrain is essentially homogeneous and regional transport is from the southwest throughout the 

year (Western Regional Climate Center, 2004, online data). The main air quality pollutant is 

total suspended particulates (TSP). The concentration of pollutants is inversely proportional to 

wind speed. Wind speed data from Rawlins, on the eastern edge of the air basin, tend to indicate 

adequate dispersion potential in the Project Area (BLM, 1987, Figure 9). Average annual wind 

speed in the Rawlins area, located approximately 55 miles east southeast of the Project Area, is 

approximately 13.6 mph, and average annual precipitation is less than 10 inches (Western 

Regional Climate Center, 2004, online data). Precipitation data from the nearest station at 

Wamsutter, approximately 25 miles south, indicates average annual precipitation of 

approximately 7.5 inches (Curtis and Grimes, 2004, online data). 
Chapter 3 - Affected Environment 

 3-5 

3.2.2 Air Quality 

Air quality modeling has not been conducted within the Project Area. Regional background air 

quality data, however, suggest that local air quality conditions are well within minimums for 

both Wyoming Ambient Air Quality Standards (WAAQS) and National Ambient Air Quality 

Standards (NAAQS). The area is characterized by few emission sources and good atmospheric 

dispersion conditions (BLM, 2003a, pg. 3-14). With respect to classification in terms of 

Prevention of Significant Deterioration (PSD) of air quality values, the Project Area is a Class II 

area. A summary of some regional criteria pollutant background levels is indicated in Table 3.2.

Table 3.2 Regional Air Pollutant Background Concentrations and State and 

Federal Ambient Air Quality Standards, WDNGDP 

Pollutant/Averaging Time Measured 

Background 

Concentration 

State and National 

Ambient Air 

Quality Standards 

Carbon Monoxide (CO) 1 

1-hour 3,336 40,000 

8-hour 1,381 10,000 

Nitrogen dioxide (NO2) 2 

Annual 3.4 100 

Ozone 3 

1-hour 169 235 

8-hour 147 157 

Particulate Matter (PM10) 4 

24-Hour 47 150 

Annual 16 50 

Particulate Matter (PM2.5) 4 

24-Hour 15 65 

Annual 5 15 

Sulfur dioxide (SO2) 5 

3-hour (National) 132 1,300 

24-hour (National) 43 365 

24-hour (Wyoming) 43 260 

Annual (National) 9 80 

Annual (Wyoming) 9 60 

1. Background data collected by Amoco at Ryckman Creek for an 8-month period during 1978-

1979, summarized in the Riley Ridge EIS (BLM, 1983). 

2. Background data collected at Green River Basin Visibility Study site, Green River, Wyoming, 

during period January-December 2001 (ARS, 2002). 

3. Background data collected at Green River Basin Visibility Study site, Green River, Wyoming, 

during period June 10, 1998 through December 31, 2001 (ARS, 2002). 

4. Background data collected by WDEQ-AQD at Emerson Building, Cheyenne, Wyoming, Year 

2002.

5. Background data collected at LaBarge Study Area the Northwest Pipeline Craven Creek Site 

1982-1983. 

Source: Environmental Assessment for the Atlantic Rim Coalbed Methane Project, Brown Cow POD, 

Carbon Co., Wyoming. 
Chapter 3 - Affected Environment 

 3-6 

3.3 SOILS 

3.3.1 Soil Types within the WDNGDP Area 

Soils within the Project Area are forming in mostly residual sandy materials weathering from the 

sandstones and shales of the Wasatch and Green River formations (Love and Christiansen, 1985) 

within the Great Divide Basin of southwestern Wyoming. Limited areas of alluvium and aeolian 

deposits occupy some of the drainage bottoms in the mostly rolling topography of the Project 

Area. Soils mapping compiled in the STATSGO data based (NRCS, 1995) identifies four 

mapping units within the boundaries of the WDNGDP (Table 3.4). 

Table 3.3 STATSGO Soil Information, WDNGDP 

STATSGO Unit 

ID Unit Name Location WDNGDP Area (Acres) % Area 

WY 139 Huguston-TeagulfWintCentral Project Area 4,328 67.5% 

WY 166 Forelle-VonasonFarsonNortheastern Project 

Area

717 11.2% 

WY 170 Dines-FluventsChrisman Northwestern Project 

Area

778 12.1% 

WY 173 Dune Land-CotopaxiTerada Southeastern Project 

Area

590 9.2% 

TOTAL 6,413 100.0% 

All field development activities associated with the proposed wells and ancillary facilities, such 

as roads and pipelines, would occur within soil mapping unit WY139 with the exception of one 

proposed well that is situated within WY170. The remaining description of soils will focus on 

soil characteristics of those soils comprising map unit WY139 and WY170 based on STATSGO 

data (NRCS, 1995). 

The dominant upland soils are predominately fine sandy loam to loam surface soils over bedrock 

to loamy subsoils that are shallow to moderately deep and well drained. Slopes range from 

gently sloping (3 percent) to steep (30 percent) with some isolated rock outcrops supporting very 

steep slopes (75 percent). The remaining mostly upland soils, occupying lower slopes, range 

from fine sandy loam to loam surface soils over fine sand to sandy clay loam subsoils that are 

moderately deep to deep and well drained. Slopes range from level (0 percent) to sloping (6 

percent).

The potential for accelerated soil water erosion and soil loss is limited to the mostly shallow to 

moderately deep soils of the steeper slopes (generally greater than 15 percent). Areas with 

slopes in excess of 15 percent represent approximately 5 to 10 percent of the Project Area. The 

potential for wind erosion is mostly moderate for the soils in the Project Area with the exception 

of the fine sandy soils forming in the limited aeolian deposits which make up about 5 percent of 

the Project Area. 

Rogrube soils likely occupy the bottoms of the larger drainages and closed playas in the Project 

Area. These loamy soils comprise approximately 5 percent of the Project Area and have 

elevated salinity (4 to 8 mmhos/cm) and sodic (SAR) (5 to 8) levels in surface and subsoil 
Chapter 3 - Affected Environment 

 3-7 

horizons (NRCS, 1995). Surface horizon values for salinity and SAR range from 0 to 4 

mmhos/cm (non-saline to slightly saline) and 2 to 5 (SAR values), respectively. Neither range of 

values for the surface horizon would pose limitations on vegetative productivity (BLM, 2003d). 

3.4 WATER RESOURCES 

Historical precipitation for the study area is reported by the National Weather Service Oceanic 

and Atmospheric Administration (NOAA) weather stations at Wamsutter, Bitter Creek, South 

Pass, and Sand Draw, Wyoming. These recording gauges surround the Project Area. The gauge 

elevations average is 7,243 feet above mean sea level. The average annual precipitation data for 

the gauges are: Wamsutter, 7.4 inches; Bitter Creek, 6.7 inches; South Pass, 14.1 inches; and 

Sand Draw, 9.66 inches. The reading at Wamsutter is the most representative for the Project 

Area. The winter period (November 15 through April 30) accounts for approximately 20 percent 

of the average annual precipitation. Average annual pan evaporation (Seminoe Dam, Carbon 

County) is 36.21 inches (Western Regional Climate Center, 2004, online data). 

3.4.1 Surface Water 

The Project Area is located within the Great Divide Basin physiographic province which is 

internally drained. Red Creek, which flows south from Cyclone Rim and Honeycomb Buttes 

into Hay Reservoir, just grazes the northwestern portion of the Project Area. The eastern 

portions of the Project Area are drained by two unnamed easterly-flowing tributaries to the Lost 

Creek Lake, a dry lakebed. All streams in the vicinity are ephemeral, flowing only in response to 

runoff. Due to the current drought conditions and extremely dry conditions in this basin, the 

limited run-off seeps into the ground and/or evaporates almost immediately. 

Hay Reservoir is located southwest of the Project Area. The dam for the reservoir is on private 

land and in the past the dam had been maintained by ranchers, but washed out many years ago. 

The current landowner in recent years repaired the dam and the reservoir is again functional, 

holding water during runoff periods (Bargsten, 2004, personal communication). 

3.4.2 Groundwater 

Groundwater aquifers in the area are principally lower Tertiary, primarily Wasatch and Ft. Union 

Formations, although deeper aquifers in Upper Cretaceous sandstone units are known to exist. 

Aquifers within the Great Divide Basin comprise a portion of the Upper Colorado River Basin 

regional aquifer system. 

Permeability of the lower Tertiary aquifers is variable and somewhat dependent on the degree of 

secondary porosity. The upper part of the Wasatch aquifer interfingers with shales and 

mudstones of the overlying Green River Formation, and portions of these units form the surface 

within the Project Area. The Wasatch-Ft. Union aquifer is commonly confined and artesian 

flows are common. Most of the freshwater within the Upper Colorado River Basin regional 

aquifer system is contained within the Wasatch and Ft. Union formations. The combined 

thickness of the two contiguous units is approximately 7,000 feet near the center of the Great 

Divide Basin. 
Chapter 3 - Affected Environment 

 3-8 

Potentiometric surface mapping of the Wasatch-Ft. Union aquifer indicates that groundwater 

flow is generally towards the center of the Great Divide Basin. A local depression of the surface 

in northeastern Sweetwater County is the result of extensive groundwater withdrawals. 

Estimated depth to groundwater is generally less than 200 feet in the vicinity of the Project Area 

(USGS, 1996, pg. I-19). 

Sandstone units within the Upper Cretaceous Mesaverde Group comprise the Mesaverde aguifer. 

Shales may form locally confined units, but in general the Mesaverde exists in hydraulic 

continuity with the overlying lower Tertiary aquifers. The Mesaverde, in turn, is hydraulically 

separated from underlying aquifers by thick, confining Lower Cretaceous shale formations. The 

Mesaverde is exposed around the margins of the Rock Springs Uplift, and relatively fresh water 

may extend a limited distance down dip. Groundwater flow is toward the central portion of the 

Great Divide Basin. In the deeper portions of the basin, the formation's groundwater tends to be 

saline or briny. In the vicinity of the Project Area, regional salinity , as measured by Total 

Dissolved Solids (TDS) values, are in the range of 3,000-10,000 mg/l (USGS, 1996, pg. I-19). 

The online database of the Wyoming State Engineer's Office (WSEO) was searched for water 

well locations within one mile of the Project Area. Three permits were located: P55110W, 

BLM, SWNE of Section 18, T24N, R96W; P155774, William Jolley and BLM, NWSE of 

Section 5, T23N, R96W; P46934W, Davis Oil and BLM, NWSE Section 5, T23N, R96W. The 

latter permit is abandoned. 

Data from the WSEO for the above and nearby wells with both active and voided water rights 

suggest that the shallow Wasatch aquifer is reached with wells of generally less than 500 feet 

depth. Static water levels typically ranged from 100 to 400 feet, but have been found as shallow 

as 30 feet. Actual yields from the shallow aquifer typically ranged from approximately 20 

gallons per minute (gpm) to approximately 70 gpm. Wells in Section 36, T24N, R97W in the 

vicinity of the Hay Reservoir produced from a deeper Wasatch/Ft. Union aquifer at depths of 

approximately 3,200 feet to 5,200 feet. Artesian flow was observed with rates up to 225 gpm. 

Wells with currently valid permits near the Project Area are principally used for stock watering 

(WSEO, 2004, online data). 

A summary of characteristics of potential aquifers within the Project Area is indicated in Table

3.4.

Table 3.4 Water-Bearing Characteristics of Some Formations, WDNGDP Area 

Formation Approximate Depth, Characteristics 

Wasatch Surface Flows to 250 gpm, TDS < 2,800 ppm 

Ft. Union 4,400 Flows to 300 gpm, TDS < 3,350 ppm 

Lewis 10,600 Sands may have artesian flows 

Almond 11,300 Flows to 100 gpm, TDS < 1,500 ppm 

Source: BLM, Rawlins Field Office 

The region surrounding the study area contains local areas of spring discharges, but the Project 

Area is located in an area of groundwater recharge.
Chapter 3 - Affected Environment 

 3-9 

Water produced in association with gas and condensate production in the Wind Dancer Unit, is 

stored in on-site tanks prior to trucking to an approved disposal facility not located on BLM 

surface. Water production averages less than 5 bbls per day per well. No produced water is 

discharged to water courses or to the surface in the Project Area. Quality of the produced water 

exhibits TDS ranges from approximately 256 ppm to approximately 14,000 ppm, depending 

upon productive horizon. 

3.5 VEGETATION, WETLANDS, AND NOXIOUS WEEDS 

3.5.1 Vegetation Cover Types 

Vegetative cover in the Project Area is representative of the semi-arid Wyoming Basin floristic 

region, where precipitation and soil parent material are controlling factors for plant composition. 

Vegetation may be sparse in areas. Cover of the Project Area is a mix of vegetation types typical 

of the basins of south-central Wyoming and is dominated by plant species that are drought 

tolerant: big sage, black sagebrush, rabbitbrush, winterfat, shadscale saltbush, gardner saltbush, 

horsebrush, spiney hopsage, greaseswood, bud sage, mustard, buckwheat, phlox, purple aster, 

paintbrush, cactus, thickspike wheatgrass, needle and thread, squirreltail, bluegrass, Indian and 

contracted ricegrass. The percent composition of major vegetation types within the Project Area 

is presented in Table 3.5. 

Table 3.5 Type and Relative Amounts of Vegetation within the WDNGDP Area 

Type Relative Amount of Vegetation 

Grassland 60% 

Sagebrush 15% 

Saltbush 10% 

Greasewood 15% 

* Percentages are approximations from a recent on-site survey and from the Hay Reservoir EA (BLM, 

1992). 

3.5.1.1 Grassland Type 

Within the Project Area, grasslands make up approximately 60 percent of the vegetative cover. 

The major grass species comprising this type are Indian ricegrass (Oryzopis hymenoides),

needle-and-thread (Stipa comata), bluebunch wheatgrass (Agropyron spicatum), western 

wheatgrass (Agropyron smithii), and thickspike wheatgrass (Agropyron dasystachyum) (BLM, 

1992).

3.5.1.2 Sagebrush Type 

Big sagebrush (Artemisia tridentate) is the most common constituent of the sagebrush type. 

Predominant subtypes include black sagebrush (Artemisia nova), bud sagebrush (Artemisia 

spinescens), Douglas rabbitbrush (Chrysothamnus vicidiflorus), and rubber rabbitbrush 

(Chrysothamnus nauseous) (BLM, 1992). 
Chapter 3 - Affected Environment 

 3-10 

3.5.1.3 Saltbush Type 

The dominant shrub is Gardener saltbush (Atriplex nuttallii) with shadscale saltbush (Atriplex 

conferifolia) and winterfat (Ceratoides lanata) common at some locations. Understory species 

include bluegrass (Poa spp.), bottlebrush squirreltail (Sitanion hystrix), Indian ricegrass, Phlox, 

and summer cypress (Kochia Americana) (BLM, 1992). 

3.5.1.4 Greasewood Type 

This type is normally located in narrow gulches and low flats which are heavily impregnated 

with alkali. Shrubs dominate the composition of this vegetation type. The dominant shrub is the 

greasewood (Sarcobatus vermiculatus) with rabbitbrush and saltbush common in the overstory. 

Bottlebrush squirreltail, foxtail barley (Hordeum jubatum), and summer cypress are common in 

the understory. Halogeton (Halogeton glomeratus), usually considered a weed, is also present 

(BLM, 1992). 

3.5.2 Wetlands and Riparian Areas 

The Wind Dancer Unit does not contain any wetland or Riparian areas. The Hay Reservoir area 

to the west of the Project Area supports riparian areas but lies outside of the Project Area.

3.5.3 Invasive/Noxious Weeds 

Increased occurrences of non-native invasive species, as well as those noxious weeds defined by 

Wyoming Statutes (WS 11-5-102.a.xi) as "the weeds, seeds or other plant parts that are 

considered detrimental, destructive, injurious or poisonous, either by virtue of their direct effect 

or as carriers of diseases or parasites that exist within this state, and are on the designated list" 

(National Agricultural Library, 2004, online data) may accompany oil and gas development. 

Wyoming statute has designated 23 species of noxious weed. In addition, under authority of the 

Wyoming Weed and Pest Control Act of 1973 (WS 11-5-119), counties may designate additional 

weeds of concern.

The Project Area has the potential for the following State-designated noxious weeds: 

x hoary cress

x Russian knapweed 

x Canada thistle

x perennial pepperweed (wet areas)

A Sweetwater county weed of concern is black henbane, which may possibly occur along roads 

and ditches (Cotterman, 2004, personal communication). 
Chapter 3 - Affected Environment 

 3-11 

3.6 RANGE RESOURCES AND OTHER LAND USES 

Livestock management operations and oil and gas extraction characterize the major land uses in 

the Project Area. 

3.6.1 Range Resources 

Due to arid conditions and limited water resources, livestock grazing of federal lands represents 

the primary form of agriculture in the WDGNP. Federal allotment 10103, Cyclone Rim, 

includes the entire WDGNP (BLM, 2003). Seasons of use are winter (cattle and sheep) and 

summer (cattle). Primary use is for cattle during the summer. Estimated carrying capacity in the 

area is 9 to 11 acres per Animal Unit Month (AUM). 

3.6.2 Other Land Uses 

The Project Area is comprised of approximately 6,400 acres of federal, BLM-administered lands. 

No state or private lands are present in the Project Area. Other land uses within and adjacent to 

the Project Area, in addition to livestock grazing, are wildlife habitat, oil and gas exploration, 

development and transmission, and dispersed recreation. 

Conventional oil and gas resources have been developed in and around the WDGNP. Five wells 

have been drilled in the Project Area; four are currently in production, and one is being redrilled. Approximately 55 acres have been disturbed by previous oil and gas development in the 

Project Area. 

3.7 WILDLIFE AND FISHERIES 

3.7.1 General Wildlife 

Mammals found in the vicinity of the Project Area include jackrabbit (Lepus spp.), cottontail 

rabbit (Sylvilagus spp.), coyote (Canis latrans), Richardson's ground squirrel (Spermophilus

richardsonii), thirteen-lined ground squirrel (Spermophilus tridecemlineatus), badger (Taxidea

taxus), and various mice. Areas of tall (> 4 feet) sagebrush along drainages serve as wildlife 

corridors, providing hiding cover from predators as well as thermal shelter for wintering wildlife. 

White-tailed prairie dogs (Cynomys leucurus), a BLM sensitive species, is known from 

sagebrush plain areas (BLM, 1987; Whitaker, 1992). 

Local bird species include horned lark (Eremophila alpestris), sage thrasher (Oreoscoptes 

montanus), mourning dove (Zenaida macroura), and common raven (Corvus coras). Small 

stock ponds in the vicinity of and immediately southwest of the Project Area and Hay Reservoir 

provide water for migratory waterfowl. 
Chapter 3 - Affected Environment 

 3-12 

3.7.2 Big Game 

Most of the Project Area is habitat for pronghorn (Antilocapra americana) and mule deer 

(Odocoileus hemionus). The combination of hills, rough breaks, draw and flats provide a 

mixture of microhabitat sites in terms of snow depth, exposure to wind, sun and forage 

availability. This is a dynamic system, as snow falls and then moves across the topography in 

response to the wind. Antelope and deer move around throughout the winter in response to 

weather conditions and the protection provided by these microhabitats. No crucial big game 

winter range has been identified within the Project Area (BLM, 1987, pg. 43). 

Wyoming Game and Fish Department (WGF) has defined the entire Project Area as winter/year 

long range for antelope. A portion of the antelope population makes use of the local habitat on a 

year long basis. During the winter months (December 1 through April 30), the area is host to a 

significant influx of animals from other seasonal ranges. Antelope in the Project Area belong to 

WGF herd unit 615 (Red Desert) (WGF, 2002, GIS data). Herd Unit 615 comprises 

approximately 2.16 million acres. Estimated population counts for this herd unit for 2002 were 

14,000 individuals with a target population of 15,000 (WGF, 2003, Lander Region, Red Desert 

Herd Unit, pgs 2-10). 

WGF has defined a spring/summer/fall range for mule deer in an area around Hay Reservoir. A 

portion of the population frequents this range outside of the winter months (December 1 through 

April 30). The range around Hay Reservoir extends over approximately 30 percent of the Project 

Area, in the western and southwestern portions. The defined range forms a rough rectangle 

about 40 sq. miles in extent, with Hay Reservoir in the northeastern part of the area. Mule deer 

in the Project Area belong to WGF herd unit 430 (Steamboat) (WGF, 2002, GIS data). Herd 

Unit 430 comprises approximately 2.5 million acres. Estimated population counts for this herd 

unit for 2002 were 3,100 individuals with a target population of 4,000 (WGF, 2003, Green River 

Region, Steamboat Herd Unit, pgs 202-222). 

Wyoming Game and Fish observation data from 1986-1991 showed the number of antelope in 

the Project Area (T24N R96W) to be 239 and mule deer to be 4 (BLM, 1987, pg. 43). Antelope 

fawn production has been low in the Red Desert Herd Unit for at least ten years. Mule deer 

population in the Steamboat Herd Unit has grown slowly since 1993, until 2002 when an 

estimated 10% decline was observed. It is believed this decline is associated with the third year 

of severe drought in the area (WGF, 2003, Green River and Lander Region Herd Unit reports). 

Elk (Cervus elaphus) are not commonly found in the study area. Sightings generally occur 

during hunting season when pressure from that activity tends to drive them from their normal 

habitat. WGF data indicate habitat within the Project Area is of limited importance to 

individuals in the area, a portion of herd unit 426 (Steamboat) (WGF, 2002, GIS data). Estimated 

population counts for this herd unit for 2002 were 1,660 individuals with a target population of 

1,200 (WGF, 2003, Green River Region, Steamboat Herd Unit, pgs 270-290).
Chapter 3 - Affected Environment 

 3-13 

3.7.3 Wild Horse Management 

The wild horse population in the Seven Lakes Herd Management Area (HMA), Great Divide 

Resource Area, is about 475 horses (BLM, 1987, pg. 42). There are two herds in the vicinity of 

the Project Area. The Stewart Creek herd is located 16 miles east of the Project Area. The 

Cyclone Rim herd is north of the Project Area. There is very little mixing of horses between the 

two herds. A small portion of the Project Area is located in the Great Divide Basin HMA, Green 

River Resource Area. Rarely do horses use the area in and around the Project Area in either 

HMA, and use by horses in the Project Area may be considered transient (Bargsten, 2004a, 

personal communication). 

3.7.4 Upland Game Birds 

The Project Area is located within sagebrush/grassland habitat common in southwestern 

Wyoming. The Project Area potentially supports areas of prime habitat for sage grouse 

(Centrocercus urophasianus). Important components of prime habitat for these birds are 

strutting grounds (leks), nesting grounds, and wintering areas; all of these components 

potentially occur in the vicinity of the Project Area. Sage grouse is designated a BLM sensitive 

species and is discussed further in Section 3.8.

3.7.5 Raptors 

The Project Area contains habitat suitable for raptors. A number of raptor species, including 

golden eagles (Aquila chrysaetos), northern harriers (Cirus cyaneus), ferruginous hawks (Buteo

regalis), Swainson’s hawk (Buteoswainsoni), prairie flacon (Falco mexicanus), and red-tailed 

hawks (Buteo jamaicensis) have been observed in the vicinity of the Project Area.

Raptors are considered sensitive species and are also discussed further in Section 3.8. 

3.8 SPECIAL STATUS PLANT, WILDLIFE, AND FISH SPECIES 

For the purposes of this EA, special status species are those listed by the Fish and Wildlife 

Service (USFWS) as threatened, endangered, proposed, or candidate species (USFWS, 2003, 

online data); or species included on BLM's Wyoming state sensitive species list (BLM, 2002, 

online data); or on the WGF native status species list (Fertig et al., 1999, online data). Only 

those species which are known or suspected to occur within the vicinity of the Project Area are 

discussed.

3.8.1 Threatened, Endangered, Proposed, or Candidate Species 

Four federally designated species have the potential to exist within the vicinity of the Project 

Area, as indicated in Table 3.5.
Chapter 3 - Affected Environment 

 3-14 

Table 3.6 Threatened and Endangered Species , WDNGDP Area 

Species Scientific Name Status

Plants

Blowout pestemon Penstomen haydenii Endangered 

Ute Ladies’-tresses Spiranthes diluvialis Threatened 

Mammals

Black-footed ferrets Mustela nigripes Endangered 

Birds

Bald eagle Haliaeetus leucocephalus Threatened 

Source: BLM, 2003c. 

Although no threatened or endangered wildlife species (TES) have been observed in the study 

area, there is potential for three of these species to occur within the vicinity of the WDNGDP. 

Bald eagle foraging probably takes place during winter, but this would be on an infrequent 

opportunistic basis. Bald eagles prefer habitat near water and cliffs or large trees for nesting. No 

such habitat exists in the area. 

Black-footed ferrets have been sited in the vicinity of Wamsutter (approximately 30 miles SE) in 

1977, 1978 and 1983. White-tailed prairie dog complexes greater than 200 acres in extent have 

been observed in the vicinity of the Project Area, indicating the potential presence of blackfooted ferret habitat. Large colonies have not been observed within the Project Area. (BLM, 

2003c, pgs. 15-16). Although the USFWS has determined that portions of an area that includes 

the Project Area meet ferret habitat criteria, black-footed ferret surveys are no longer required in 

this township (Kelly, 2004, letter). However, to protect both potential black-footed ferret habitat 

and white-tailed prairie dog (a BLM Sensitive Species), the BLM does attempt to avoid impacts 

to prairie dog towns, which are utilized by mountain plover, burrowing owls, and swift fox. 

Two federally listed plant species were identified by the USFWS as potentially present in the 

general area . Ute Ladies’-tresses (threatened) occurs in seasonally moist soils and wet meadow 

drainages below 7000 feet elevation. Blowout penstemon (endangered) has been documented 

along the Killpecker Sand Dunes near Rawlins (BLM, 2003c, pg.17). Habitat for these plants 

does not occur within the Project Area. 

As this is a closed drainage basin and does not contribute to the Colorado River watershed, there 

would be no impact on Colorado River endangered species. 

If, through a biological evaluation, the BLM determines that the Proposed Action may affect a 

listed species or critical habitat, consultation with the USFWS is required. 

3.8.2 Sensitive Species 

A number of animal and plant species potentially present in the Project Area have been accorded 

“sensitive species” status by BLM. Thirty-five of the 78 Wyoming species occur within the 

boundaries of the Rawlins Field Office (BLM, 2002, online data). Based upon habitat criteria, 

sensitive species potentially present in the vicinity of the Project Area are indicated in Table 3.6

(BLM, 2003c, pg. 19). 
Chapter 3 - Affected Environment 

 3-15 

Table 3.7 BLM Sensitive Species Potentially Found in Vicinity of WDNGDP 

Common Name Scientific Name Agency Status Heritage Program 

Status * 

Birds 

Ferruginous hawk Buteo regalis BLM, FSR2 Not Listed 

Western burrowing owl Athene cunicularia BLM, FSR2 G4/S3B,SZN 

Mountain plover Charadrius montanus BLM, FSR2 G2/S2B,SZN 

Loggerhead shrike Lanius ludovicianus BLM, FSR2 G5/S4B, SZN 

Sage Thrasher Oreoscoptes montanus BLM G5/S3B, SZN 

Baird's sparrow Ammodramus bairdii BLM, FSR2 G5/S3B, SZN 

Brewer's sparrow Spizella breweri BLM, FSR2 G5/S3B,SZN 

Grasshopper sparrow Ammodramus savannarum WYGF G5/S3B,SZN 

Sage sparrow Amphispiza belli BLM, FSR2 G5/S3B,SZN 

Greater sage grouse Centrocercus urophasianus BLM, FSR2 Not Listed 

Mammals 

White-tailed prairie dog Cynomys leucurus BLM, FSR2 G4/S2S3 

Swift fox Vulpes velox BLM, FSR2, WGF G3/S2S3 

Townsend's big-eared 

bat

Plecotus tonwsendii BLM, FSR2, WGF G4/S1B,S2N 

Plants

Nelson's milkvetch Astragalus nelsonianus BLM G2/S2 

Cedar rim thistle Cirsium aridum BLM G2Q/S2 

Gibben's beardtongue Penstemon gibbensii BLM G1/S1 

* Heritage Program Rankings 

FSR2 - Forest Service Region 2 Sensitive Species. 

WYNDD uses a standardized ranking system developed by The Nature Conservancy's Natural Heritage Network to assess the 

global and statewide conservation status of each plant and animal species, subspecies, and variety. Each taxon is ranked on a 

scale of 1-5, from highest conservation concern to lowest. Codes are as follows: 

G Global rank: Rank refers to the rangewide status of a species. 

T Trinomial rank: Rank refers to the rangewide status of a subspecies or variety. 

S State rank: Rank refers to the status of the taxon (species or subspecies) in Wyoming. State ranks differ from state to state.

1 Critically imperiled because of extreme rarity (often known from 5 or fewer extant occurrences or very few remaining individuals) 

or because some factor of a species’ life history makes it vulnerable to extinction. 

2 Imperiled because of rarity (often known from 6-20 occurrences) or because of factors demonstrably making a species vulnerable

to extinction. 

3 Rare or local throughout its range or found locally in a restricted range (usually known from 21-100 occurrences). 

4 Apparently secure, although the species may be quite rare in parts of its range, especially at the periphery. 

5 Demonstrably secure, although the species may be rare in parts of its range, especially at the periphery. 

H Known only from historical records. 1950 is the cutoff for plants; 1970 is the cutoff date for animals. 

X Believed to be extinct. 

A Accidental or vagrant: A taxon that is not known to regularly breed in the state or which appears very infrequently (typically refers 

to birds and bats). 

B Breeding rank: A state rank modifier indicating the status of a migratory species during the breeding season (used mostly for

migratory birds and bats). 

N Nonbreeding rank: A state rank modifier indicating the status of a migratory species during the non-breeding season (used mostly 

for migratory birds and bats) 

ZN or ZB Taxa that are not of significant concern in Wyoming during breeding (ZB) or non-breeding (ZN) seasons. Such taxa often

are not encountered in the same locations from year to year. 

U Possibly in peril, but status uncertain; more information is needed. 

Q Questions exist regarding the taxonomic validity of a species, subspecies, or variety. 

? Questions exist regarding the assigned G, T, or S rank of a taxon. 

Western burrowing owls and loggerhead shrikes are summer residents of grasslands and prairie 

shrub habitat. Furthermore, Western burrowing owls also utilize prairie dog towns as nesting 

habitat. Sage thrashers and sage sparrows are found in prairie and mountain shrub environments. 

Brewer's sparrows are summer residents found principally in shrubland habitats. Baird's 
Chapter 3 - Affected Environment 

 3-16 

sparrows are uncommon summer residents typically found in short-grass prairie locales 

(Wyoming GAP Analysis, 2001, online data; Udvardy, 1993, BLM, 2002). 

Swift fox are fairly common residents occurring over much of Wyoming and will also commonly 

utilize old prairie dog burrows as den locations. It is a mostly solitary, nocturnal predator. 

Townsend's big-eared bat is a widely distributed but rare species which forms nursing colonies 

(Wyoming GAP Analysis, 2001, online data; Whitaker, 1992). 

3.8.2.1 Raptors 

BLM data show 20 potential raptor nest sites within or adjacent to the Project Area. Ferruginous 

hawks are particularly common. At least four of the five nests within the Project Area have been 

identified as belonging to ferruginous hawks.

3.8.2.2 Mountain Plover 

Mountain plover was classified as a species proposed for listing by USFWS, but that agency has 

dropped the species from further consideration. BLM considers this species as sensitive and 

protective measures continue to apply to actions potentially affecting this species. Much of the 

Project Area has potential habitat for mountain plover, which is often associated with prairie dog 

towns.

3.8.2.3 Sage Grouse 

BLM records show eight greater sage grouse leks and/or nesting habitat within or in the vicinity 

of the Project Area. Probable sage grouse habitat is present in the Project Area. Statewide, sage 

grouse have exhibited a fluctuating, but overall decreasing population trend since WGF began 

monitoring in 1967. Disruption and fragmentation of sagebrush habitat may be responsible for a 

part of this decline (Bill Barrett Corporation, 2004, pg. 3-87). The species has also shown a high 

sensitivity to West Nile virus (Bills, 2004, personal communication). On April 15, 2004, the 

USFWS announced its intention to initiate a review of the status of the greater sage grouse. The 

notice initiated a 90-day review to determine whether to propose the species for listing as 

threatened or endangered.

3.8.4 White-Tailed Prairie Dog 

White-tailed prairie dogs inhabit sagebrush plains at higher elevations than those frequented by 

their black-tailed cousins. White-tailed prairie dogs are less colonial, with only a few of their 

burrows interlink with those of other individuals (Whitaker, 1992, pg. 411). A white-tailed 

prairie dog complex was observed in the Project Area during recent onsite inspections (Fetzer, 

2004, personal observation).

3.8.5 Sensitive Plant Species 

Potential habitat for three sensitive plant species occurs within the Project Area. Nelson's 

milkvetch occurs in alkaline soils in sparsely vegetated shale slopes and sagebrush communities 
Chapter 3 - Affected Environment 

 3-17 

between 5,200 and 7,600 feet elevation. Cedar rim thistle occurs on barren chalky and sandyshaley soils between 6,700 and 7,200 feet. Gibben's beardtongue may be found in habitats 

similar to cedar rim thistle, but at elevations both slightly lower and higher (BLM, 2002). 

3.9 RECREATION 

Recreation activities within the Project Area are characterized as dispersed; there are no 

developed recreational facilities or sites (BLM, 2003). Primary activities in the area include 

hunting for pronghorn, mule deer, upland game birds, coyotes, and small game. Camping, 

hiking, wildlife and wild horse viewing, off-road vehicle (ORV) use, and general sightseeing are 

other recreational opportunities provided in the area inclusive of the Project Area..

3.10 VISUAL RESOURCES 

The landscape of the Project Area is rolling sagebrush steppe comprised mostly of grassland and 

sagebrush vegetation types. The varying level of sagebrush dominance is the major source of 

natural visual contrast across the area in addition to the mostly rolling terrain and isolated rim 

areas. The Project Area is mostly free of tall rock outcrops or abrupt breaks in slope. Although 

natural scenes dominate the area, human intrusions include existing oil and gas wells, bladed and 

two-track roads, stock ponds, and fences. 

The BLM-administered federal lands that comprise all of the Project Area are classified by the 

BLM using the Visual Resource Management (VRM) System. All lands within the Project Area 

are classified as Class III (BLM, 1990, map 24). This classification indicates that the grass and 

sagebrush lands appear moderately altered by oil and gas development and grazing 

improvements. Additional modifications to the landscape from new activities in the area should 

be compatible or complementary to the existing scenic character and be moderate in extent 

3.11 CULTURAL RESOURCES 

Archeological studies of south-central Wyoming indicate that the area has been inhabited by 

prehistoric peoples for at least 10,000 years. A chronology of the area is indicated in Table 3.7.

Table 3.8 Prehistoric Chronology of the Wyoming Basin 

Period Phase Age (B.P.) 

 Paleoindian 12,000 - 8500 

Early Archaic Great Divide 8500 - 6500 

 Opal 6500 - 4300 

Late Archaic Pine Spring 4300 - 2800 

 Deadman Wash 2800-2000/1800 

Late Prehistoric Uinta 2000/1800 - 650 

 Firehole 650 - 300/250 

 Protohistoric 300/250 - 150 

Source: BLM (2003a). Based on Metcalf (1987), as modified by Thompson and Pastor (1995). 
Chapter 3 - Affected Environment 

 3-18 

3.11.1 Previous investigations 

For the purpose of documenting all known cultural resource sites and previous Class III cultural 

resource investigations within the study area, a records search was conducted through the 

Wyoming State Historic Preservation Office (SHPO) Cultural Records Office (CRO). A total of 

11 sections were researched. The 11 sections consist of approximately 7,040 acres largely within 

the Project Area. The CRO records search results revealed a total of 38 previous Class III 

cultural resource investigations and seven previously recorded or reported sites. The previous 

investigations were comprised of both small (well related) block inventories and linear surveys, 

primarily from pipeline construction. The small block investigations accounted for surface 

inspection of 210 acres, or approximately 3.3 percent of the entire study area. Acreage 

inventoried from linear investigations could not be computed from the available information 

(Davis and others, 2004; Pastor, 2004, personal communication; BLM, 1992, pg. 26).

The sections for which a CRO records search was conducted for the Proposed Action are: 

x T24N, R96W: Sections 14, 15, 16, 17, 18, 19, 20, 21, 22, 27, 28, 29, 30, 31, 32, 33, 34, 

and 35

There are relatively few sites recorded in relation to the number of previous investigations 

conducted. When the total number of investigations (38) is divided by the total number of 

recorded sites (7), it indicates that previous investigations have identified and recorded 

approximately 0.18 cultural site per survey. It is apparent that the Project Area is one of 

relatively low site density. Of the seven recorded sites, only two prehistoric open camps in 

sections 20 (48SW13795) and 29 (48SW15208), had been evaluated as eligible for listing on the 

National Registry of Historic Places (NRHP) (Davis and others, 2004).. 

3.11.2 Site Types To Be Expected 

3.11.2.1 Prehistoric 

Based on the CRO records search information, and inventories from nearby areas, the most 

common site type to be expected are those associated with camp/occupation sites. Sites exhibit a 

variety of activities and manifestations, which may include:

x camp/occupation sites (i.e. hearths, stone circles and possibly pit houses) 

x food cooking and processing 

x lithic workshops (exhibiting the latter stages of tool manufacture or tool reworking); an 

abundance of camp related tools (such as manos, metates, pottery, awls, gravers and 

needles) 

x lithic scatter 

x isolated hearths 

The CRO records search for the Project Area indicated a total of five prehistoric sites from 

previous inventories. These included three camps and two sites consisting of lithic scatter. Two 
Chapter 3 - Affected Environment 

 3-19 

of the camps, as indicated above, were evaluated as eligible for NRHP listing (Davis and others, 

2004, Pastor, 2004, personal communication). 

Given the relative flatness of the local terrain, all of these cultural site types can be expected in 

nearly any topographic situation present in the Project Area. Experience in the general area has 

shown that sites typically cluster along major collection drainages (such as Red Creek), around 

playa lakes and in select dunal situations. A few sites have been located on exposed ridges, 

which are generally areas of perceived higher site density. 

Other site types which may be present include stone alignments (cairns, circles, and drive lines). 

These site types are generally found on the crests and upper slopes of ridges, the tops of buttes. 

and in some other elevated topographic situations. 

Stone circles are commonly found throughout Wyoming and adjacent states. Also known as tipi 

rings, they are often found in association with camp sites and are widely considered to represent 

weights placed around the bottom of the tipi to keep out wind and cold. Other more isolated 

stone circles are thought to represent ceremonial or vision quest sites. 

If kill sites are present, then it can also be assumed that faunal processing sites are present. Also 

to be expected are floral processing sites characteristic of the aboriginal hunting and gathering 

cultures which inhabited this portion of the arid west. 

Burial sites, although rare and unlikely, may be present wherever aboriginal peoples were 

present. Similarly, none of the raw lithic materials preferred for tool manufacture (chert, 

quartzite, obsidian, basalt or even porcelanite) are available in the geologic formation present in 

the immediate vicinity, and quarries and large lithic workshop sites are not expected. 

3.11.2.2 Historic 

Four historic sites were listed by the CRO records search information. The sites consisted of 

three areas of debris scatter in sections 19 and 22 and one cairn in Section 28. All four sites are 

considered as ineligible for NRHP listing (Davis and others, 2004; Pastor, 2004, personal 

communication).

3.11.3 Native American Religious Concerns 

Native American resources or religious concerns have not been previously identified in the 

Project Area. Tribal representatives did not respond to the scoping notice with concerns in this 

area. The BLM will consult with the tribes at the project-specific level if sensitive sites are 

identified as a result of the Class III inventory. 

3.11.4 Current Investigations 

Site-specific Class III Inventory surveys were conducted during April, 2004, on 11 of the 

proposed Project well pads, access roads, and pipeline ROWs. The Haystack 11 location had 

been previously surveyed. An inventory was conducted of a 10 acre area centered around each 
Chapter 3 - Affected Environment 

 3-20 

well pad. Linear access features were surveyed out to 50 feet on either side of the center line. A 

total of 158.5 acres was surveyed, or approximately 2.4 percent of the Project Area. 

Overall, the site density for the Project Area is evaluated as low. The current surveys located 

two new and one previously identified cultural sites. The previously identified site 

(48SW15208) and one of the two newly-discovered sites (48SW15278) represent prehistoric 

open camps. Both are considered eligible for listing on the NRHP. The other newly-discovered 

site is a historic cairn which is not considered eligible for listing. 

3.12 SOCIOECONOMICS 

The Project Area occurs in a relatively isolated part of Wyoming, in the heart of the Great Divide 

Basin. The Project is located in Sweetwater County, close to the borders with Carbon County, 

on the east, and Fremont County on the north. Principal access is from the south, so it would be 

Sweetwater and Carbon counties and the communities of Rock Springs, Wamsutter, and Rawlins 

that may be primarily affected by the Proposed Action. 

3.12.1 Population and Demographics 

Both Sweetwater and Carbon counties are two of the four Wyoming counties which exhibited 

population declines between 1990 and 2000. Carbon County declined the greatest of any county 

in Wyoming, 6.1 percent. Sweetwater County's population declined by 3.1 percent. Population 

figures and trends for the two counties are illustrated in Table 3.8 (WDAI, 2004, online data). 

Table 3.9 Population Trends, WDNDGP Project Vicinity 

County or Town Population, 1990 Population, 2000 % Change 

Carbon County 16,659 15,639 -6.1% 

Rawlins 9,380 8,538 -9.0% 

Sweetwater County 38,823 37,613 -3.1% 

Rock Springs 19,050 18,708 -1.8% 

Wamsutter 240 261 8.8% 

State of Wyoming 453,588 493,782 8.9% 

Source: U.S. Census Bureau, retrieved from WDAI (2004). 

Carbon and Sweetwater counties, as well as the State of Wyoming, exhibit relatively low ethnic 

diversity with respect to the rest of the nation. Ethnicity statistics are indicated in Table 3.9

(U.S. Census Bureau, 2004, online data). 

Table 3.10 Population Ethnicity, WDNDGP Project Vicinity, 2000 

Ethnic Group Carbon 

County 

Sweetwater 

County 

State of 

Wyoming 

White 90.1% 91.6% 92.1% 

Black or African American 0.7% 0.7% 0.8% 

American Indian and Alaskan Native 1.3% 1.0% 2.3% 

Asian 0.7% 0.6% 0.6% 

Native Hawaiian and other Pacific Islander 0.1% - 0.1% 

Other 5.2% 3.6% 2.5% 

Persons reporting two or more ethnic groups 2.1% 2.4% 1.8% 
Chapter 3 - Affected Environment 

 3-21 

Ethnic Group Carbon 

County 

Sweetwater 

County 

State of 

Wyoming 

Hispanic or Latino 13.8% 9.4% 6.4% 

White, not of Hispanic or Latino origin 82.4% 86.9% 88.9% 

Language other than English spoken at home 10.5% 6.4% 7.5% 

Source: U.S. Census Bureau (2004). 

High school graduates comprise 83.5 percent and 87.4 percent of the Carbon and Sweetwater 

counties populations, respectively, compared to 87.9 percent for the State of Wyoming. 

Residents achieving a college Bachelor's degree or higher comprise 17.2 percent and 17.0 

percent, respectively for Carbon and Sweetwater counties, compared to 21.9 percent for the State 

of Wyoming. 

3.12.2 Economy, Employment, and Housing 

Employment in Carbon and Sweetwater counties is dominated by services, retail trade, mining 

(including oil and gas development), and local government (including public schools). Only a 

miniscule fraction of employment is in the farming sector. Non-farm employment by industry 

sector, and changes over a 10-year period, are indicated in Table 3.10 (U.S. Census Bureau, 

2004, online data; WDOE, 2004, online data). 

Table 3.11 Employment by Industry Sector, WDNGDP Vicinity 

Carbon County Sweetwater County Industry Sector 

1990 2000

%

Change 1990 2000

%

Change 

Total Farm 538 603 10.8% 220 205 -7.3% 

Total Non-Farm 9,352 9,201 -1.6% 22,636 24,231 6.6% 

Total Private Sector 7,203 7,164 -0.5% 18,607 19,964 6.8% 

Agricultural, Services, 

Forestry, Fishing 

106 254 58.3% 81 163 50.3% 

Mining (including oil and 

gas)

934 318 -193.7% 4,989 3,725 -33.9% 

Construction 515 699 26.3% 1,533 1,540 0.5% 

Manufacturing 684 625 -9.4% 745 1,639 54.5% 

Transportation / Utilities 736 615 -19.7% 1,987 1,809 -9.8% 

Wholesale trade 173 180 3.9% 648 637 -1.7% 

Retail trade 1,686 1,757 4.0% 3,739 4,476 16.5% 

Finance / Insurance / 

Real Estate 

522 575 9.2% 1,125 1,210 7.0% 

Services 1,847 2,141 13.7% 3,760 4,765 21.1% 

Government 2,149 2,037 -5.5% 4,029 4,267 5.6% 

Source: U.S. Census Bureau (2004); WDOD (2004). 

For 2002, the unemployment rate for Carbon and Sweetwater counties was 4.6 percent and 4.7 

percent, respectively, compared to 4.2 percent for the State of Wyoming. 

Mining and oil and gas activity represent fewer jobs than formerly, although the industry 

continues to be a significant employer in Sweetwater County. Significant losses in jobs from the 

mining and oil and gas sector have been offset by increases in services, retail trade, construction 

and manufacturing. Closure of several coal mines has been the main cause of loss of jobs in the 
Chapter 3 - Affected Environment 

 3-22 

mining sector in Carbon County (BLM, 2003a, pg. 3-48). Trona and coal mining, as well as 

natural gas development, are significant employers in Sweetwater County (Sweetwater 

Economic Development Association, 2004, online data). Sweetwater County ranks third among 

Wyoming counties in 2000 coal production with 9.96 million tons produced. In 2000, Carbon 

and Sweetwater counties ranked fourth and sixth in the state in numbers of APDs filed with the 

Oil and Gas Conservation Commission, and ranked third and seventh in gas production (BLM, 

2002a).

Median household income in 2000 was $36,060 and $46,537 in Carbon and Sweetwater 

counties, respectively. These levels represent 91.9 percent and 118.6 percent of the Wyoming 

statewide median income. The levels rank Carbon and Sweetwater counties tenth and fifth, 

respectively, among the 23 counties in Wyoming (WDAI, 2004, online data). The median value 

of owner-occupied housing units in 2000 was $76,500 and $104,200, respectively, for Carbon 

and Sweetwater counties (WDOE, 2004, online data). There were 8,380 and 16,053 housing 

units, respectively, in Carbon and Sweetwater counties in 2002 (U.S. Census Bureau, 2004, 

online data). 

3.12.3 Local Government Revenues 

A summary of county revenues is indicated in Table 3.11. 

Table 3.12 County Revenues, Carbon and Sweetwater Counties, 2003. 

Revenue Source Carbon County 

FY 2003 

Sweetwater County 

FY 2003 

Property taxes 24,595,682 78,174,590

Sales taxes 13,245,550 52,141,752

Use taxes 1,277,668 8,422,017

Retail Taxes 4,700,804 17,543,954

Source: WDAI (2004), Wyoming Taxpayers Association (2003) 

3.12.4 Environmental Justice 

Executive Order 12898 directs federal agencies to address disproportionately high or adverse 

effects to human health and environment on minority or low income populations. For Carbon 

County, 9.8 percent of families and 12.9 percent of individuals earned incomes placing them at 

poverty levels in 1999. For Sweetwater County, the poverty numbers in 1999 were 5.4 percent 

of families and 7.8 percent of individuals, respectively. This compares to numbers for the State 

of Wyoming of 8.0 percent of families and 11.4 percent of individuals in poverty in 1999. 

Carbon County thus has somewhat higher and Sweetwater County somewhat lower poverty 

levels than the state as a whole. 

As discussed above, ethnic minorities make up a small portion of the population in both counties 

and in the State of Wyoming. 
Chapter 3 - Affected Environment 

 3-23 

3.13 TRANSPORTATION 

Primary access to the WDNGDP is provided by a combination of Interstate Highway (I-80), 

county, and BLM improved and unimproved roads. Main routes to the Project Area are the 

county-maintained, dirt-surfaced Bar-X Road and Tipton Road, both of which exit I-80 west of 

west of Wamsutter, Wyoming. Both roads travel north to the county-maintained, dirt-surfaced 

Luman Road. From the Bar-X Road intersection with the Luman Road, travel east to the TiptonNorth Road. Turn north on the Tipton-North Road, RD 67 toward Hay Reservoir and fork to the 

right onto BLM Road 3219 to the Project Area. The Tipton Road route from I-80 intersects the 

Luman Road, west on Luman to the Tipton-North Road, RD 67 and north to BLM RD 3219. 

Traffic to and from the area stems mostly from oil and gas-related activity and livestock 

management. Supplies used for drilling and construction will likely be transported by truck to 

the site from supply centers in Rock Springs, Rawlins, and Casper, Wyoming. All materials and 

equipment would be packaged, loaded, and transported per state (Wyoming Public Utilities 

Commission) and federal (DOT) requirements. 

The BLM requires all roads on BLM-administered lands be designed and constructed or 

reconstructed to minimum standards per BLM Manual Section 9113. Existing roads in the 

Project Area are maintained in compliance with BLM standards. 

3.14 HEALTH AND SAFETY 

Current activities and conditions potentially contributing to the health and safety of individuals 

working or recreating in the Project Area include: 

x occupational hazards associated with oil and gas drilling and field operations,

x risks associated with vehicle operations on improved and unimproved county and BLM 

roads and potential for vehicle collisions with big game species, 

x hunting related firearm-related accidents, and 

x natural hazards such as flash floods and range fires. 

3.15 NOISE 

Sources of noise in the Project Area, other than those associated with natural sources such as 

wind and storms, would include vehicular traffic on local, county .and BLM roads, temporary oil 

and gas maintenance and repair operations, and overhead aircraft passage. In general, day and 

night noise levels in the area would compare to typical levels representative of a rural 

environment with the absence of any noise generating facilities in the Project Area. 
 4-1 

CHAPTER 4 

ANALYSIS OF ENVIRONMENTAL 

CONSEQUENCES

4.0 INTRODUCTION 

This chapter discusses environmental consequences of the Proposed Action and of the No Action 

Alternative. It also discusses potential cumulative impacts (i.e., those impacts resulting from the 

development of the Proposed Action added to existing and ongoing activities in the vicinity of 

the Project Area). Environmental consequences are discussed for each resource in the following 

sections. Mitigation measures and residual impacts are discussed, where appropriate, and have 

been summarized in Appendix B. Mitigation measures are recommended for some resources to 

further minimize impacts. The Proposed Action has been developed to minimize impacts. 

An environmental consequence or impact is defined as a modification in the existing 

environment brought about by the Proposed Action or an alternative. Impacts can be a primary 

result of the action (direct) or a secondary result (indirect), and can be permanent or long-lasting 

(long-term) or temporary and of short duration (short-term). Impacts can vary in degree from 

only a slight discernible change to a total change in the environment. 

Short-term impacts are effects on the environment that occur during and immediately after well 

pad construction, drilling, completion, testing, and/or production facility installation, and last up 

to one to two years, or until completion of interim reclamation. Although short in duration, such 

impacts can be obvious and disruptive. For this project, short-term impacts are defined as lasting 

two years or less. Long-term impacts are changes made in the environment during construction 

and operation of the project that remain longer than two years and perhaps for the life of the 

project (approximately 20 years) and beyond. 

4.1 GEOLOGY, MINERALS, AND PALEONTOLOGY 

4.1.1 The Proposed Action 

Construction using techniques approved by the BLM to minimize disturbance would result in 

some impact to local topography, including cut and fill operations for the well pads, facilities, 

and road construction. Currently, and in the foreseeable future, there are no known exploitable 

mineral resources within the vicinity of the Proposed Action. Development of the Proposed 

Action would have minimal impacts to local topography and none to mineral resources. 

The Project Area is underlain by rock layers not known to exhibit high probabilities of 

containing significant vertebrate fossils. Applicant-committed mitigation measures, discussed in 

Appendix B, would minimize the possibility of loss in the event of discovery of significant 

fossils. 
Chapter 4 - Analysis of Environmental Consequences 

 4-2 

4.1.2 The No Action Alternative 

Impacts would be similar to the Proposed Action, with the exception that no modifications to 

local topography would occur. No negative impacts to paleontological resources would occur. 

4.2 AIR QUALITY 

Issues relating to impacts from the Proposed Action were concerned with possible negative 

impacts to air quality resulting from increased emissions from drilling and production activities. 

4.2.1 The Proposed Action 

Air quality impacts would result from particulates emissions from unpaved roads and well pads 

associated with construction and ongoing maintenance operations, from vehicle emissions during 

construction and operation, and from aspects of the gas and condensate production phase. The 

latter consist principally of: 

x Three-phase separation (water, gas, and condensate) 

x glycol dehydration and 

x condensate storage (including flashing emissions). 

Recently, the BLM has issued a Final Environmental Impact Statement for the Desolation Flats 

Natural Gas Development Project (BLM, 2004). The proposed project is located approximately 

60 miles south of the Project Area and targets similar productive horizons. Detailed air quality 

modeling was conducted for Alternative A of this NEPA analysis. Alternative A consists of the 

drilling and production of 592 gas wells at 555 locations with an assumed 65 percent production 

rate, leading to 385 producing wells. Planned gas compression for the field development is 

estimated at 32,000 horsepower. Modeling was conducted at sub-grid, near-field (to 50 km) and 

far-field (400 by 500 km study area) levels.

The results of modeling studies indicate that no adverse impacts to air quality from the 

Desolation Flats Project alone are anticipated as a result of development of any alternative for 

sub-grid or near-field domains. The Proposed Action will comply with all state and national air 

quality standards. Studies done for the Desolation Flats FEIS suggest the possibility of some 

contribution to far-field visibility reduction within certain Class I airsheds. Studies indicate that 

development associated with the Desolation Flats Project would contribute to far field visibility 

impacts when combined with all other human development in the area. The Proposed Action 

would not materially detract from the area's far field visibility. Localized increases in criteria 

pollutants would occur, but maximum concentrations would be below applicable federal and 

state standards. 

Because the Proposed Action does not involve additional gas compression, the most comparable 

modeling results from Desolation Flats are those based on individual well studies. Near-field 

modeling results from the Desolation Flats Final EIS are illustrated in Table 4.1 and Table 4.2.
Chapter 4 - Analysis of Environmental Consequences 

 4-3 

Table 4.1 Near-Field Ambient Air Quality Impacts (μg/m3

)

Pollutant Averaging 

Period

Total

Project

Impact

Monitored

Background

Level 

Maximum

Impact

Plus

Background

National

Ambient

Air

Quality 

Standard

Wyoming 

Ambient

Air

Quality 

Standard 

Colorado 

Ambient 

Air

Quality 

Standard 

Percentage

of Most 

Stringent 

Ambient 

Air Quality

Standard 

NO2 Annual 1.51 3.4 4.91 100 100 100 5% 

SO2 3-hour 0.15 29 29.15 1,300 1,300 700 4% 

SO2 24-hour 0.08 18 18.08 365 260 365 7% 

SO2 Annual 0.02 5 5.02 80 60 80 8% 

PM10 24-hour 4.88 47 51.88 150 150 150 35% 

PM10 Annual 1.55 16 17.55 50 50 50 35% 

Table 4.2 Near-Field Increment Comparison(μg/m3)

Pollutant Averaging 

Time

Total Project 

Impact

PSD Class II 

Increment

Percentage of 

Class II Increment 

NO2 Annual 1.51 25 6%

SO2 3-hr 0.15 512 0.03% 

SO2 24-hr 0.08 91 0.1% 

SO2 Annual 0.02 20 0.1% 

PM10 24-hr 4.88 30 16%

PM10 Annual 1.55 17 9%

Source: Desolation Flats Natural Gas Field Development Project Final EIS, BLM Rock Springs and 

Rawlins Field Offices. 

The Operator would take measures to minimize impacts to air quality. Non-particulate emissions 

would be minimized by ensuring that vehicles, rig engines, and similar equipment are maintained 

in proper operational condition. Watering of Project access roads, as required, would achieve 

reductions in PM10 particulate emissions of 50 percent (BLM, 2003b, pg 4-11), or better. 

4.2.2 The No Action Alternative 

Under the No Action Alternative, proposed development would not occur and no Project 

emissions would be generated. 
Chapter 4 - Analysis of Environmental Consequences 

 4-4 

4.3 SOILS 

Issues relating to potential impacts to this resource from development of the Proposed Action 

were concerned with possible negative impacts to sensitive soils and potential damage to 

biological soil crusts. 

Sensitive soils in the WDNGP are those occupying steeper slopes and the drainage and playa 

bottoms. Potential for accelerated erosion from steeper slopes and the potential limitations of 

reestablishing vegetation in disturbed saline and/or sodic soils are the issues of concern arising 

from proposed implementation of the Proposed Action. 

4.3.1 The Proposed Action 

Implementation of the Proposed Action would result in disturbance to soils from construction of 

roads, pipelines, and well sites. Anticipated impacts are: 

x Clearing or mowing of protective vegetative cover at well sites and along pipeline 

corridors resulting in increased potential for accelerated soil erosion. 

x Burial and loss of productivity beneath all-season, graveled roads and maintained, 

graveled well pads. 

x Mixing of soil materials by pipeline trenching and burial, and by excavation of reserve 

pits at each well site. 

Total maximum, short-term soil disturbance would be approximately 103.4 acres of the 

approximately 6,400-acre project area for 12 multi-well pads plus pipeline and access roads 

(87.8 acres for 12 single well pads plus facilities) (Table 2.3). Following near-term, postconstruction reclamation of those disturbed areas and soils no longer subject to continuing use 

and disturbance, remaining long-term surface disturbance would total approximately 61.9 acres 

for both types of facilities. Proposed locations for facilities have been situated in areas of low 

slopes, and therefore the potential for accelerated erosion would be minimized under the 

Proposed Action (Figure 1.2). The proposed locations avoid drainage bottoms and areas where 

overland flow could accumulate. Disturbance to potentially saline and/or sodic soils would not 

occur as neither pipelines nor access roads cross these bottomland soils. 

Biological soil crusts are well adapted to severe growing conditions, but poorly adapted to 

compressional disturbances such as those resulting from trampling or vehicle off-road driving 

(BLM, 2004, pgs. 2-56 to 2-57). Applicant-committed measures are designed to reduce off-road 

travel. Total long-term surface disturbance of the Project Area would be approximately one 

percent. Where biological crusts do occur in the vicinity of the Project Area, they can be 

adversely impacted or eliminated as a functional component of the soil. 

All disturbed soils occupying areas of short-term disturbance would be reclaimed after cessation 

of drilling and construction of pipelines and access roads per BLM requirements and COAs 

presented in Appendix B. Areas of long-term disturbance would also be reclaimed following 

the decommissioning of facilities per BLM specifications.
Chapter 4 - Analysis of Environmental Consequences 

 4-5 

4.3.2 The No Action Alternative 

Under the No Action Alternative, none of the proposed activities would occur. Disturbance of 

soils by oil and gas well drilling and field development would not occur. Grazing-associated 

impacts would continue at their current levels. 

4.4 WATER RESOURCES 

Issues relating to potential impacts to this resource from development of the Proposed Action 

were concerned with possible negative impacts to groundwater resources, in particular possible 

effects associated with hydraulic fracturing technology. 

4.4.1 The Proposed Action 

Produced water discharge from the Proposed Action would not adversely affect surface water 

because there would be no surface discharges. The Spill Prevention, Control and 

Countermeasure (SPCC) Plan, as required under federal law, has been prepared and submitted 

for each existing site. 

Surface water would be impacted by some short-term erosion. As a result of increased run-off 

from roads and well pads, there would be some erosion and resulting soil deposition into small 

intermittent drainages. Mitigation measures would be implemented to reduce these impacts. 

Groundwater would not be adversely affected because there would be no surface discharges 

which would infiltrate into the groundwater system, and because proper drilling practices would 

be utilized which prevent cross-aquifer contamination from the drill holes. Produced water 

would be disposed off federal surface in a manner approved by the BLM. 

Hydraulic fracturing is a recognized and mature technology widely used within the petroleum 

industry. Safe fracture stimulation performance would be achieved by ensuring that proper 

casing and cementing procedures had been followed prior to initiating stimulation. All fracture 

treatment fluids would flow back from the wellbore and would be recovered, to be disposed off 

federal surface in a manner approved by the BLM and consistent with WOGCC regulations. 

Only the target productive horizon would be impacted, within a short radius of the borehole. 

Data from the WSEO indicate that local stock aquifers occur at depths from near surface to 

approximately 700 feet. The Project objective horizons are located a depths of 6,000 to 13,000 

feet and impermeable or low permeability rock layers occur between the objective horizons and 

the stock aquifers. No shallow aquifers potentially or actually used for stock watering purposes 

would be affected. The geologic nature of the target productive formations require the use of 

hydraulic fracturing techniques to achieve economic success and accomplish the purpose and 

need of the Project. 
Chapter 4 - Analysis of Environmental Consequences 

 4-6 

4.4.2 The No Action Alternative 

Under the No Action Alternative, proposed development would not occur and there would be no 

Project effects to surface water or groundwater. 

4.5 VEGETATION, WETLANDS, AND NOXIOUS WEEDS 

Issues of concern regarding implementation of oil and gas field development activities in the 

WDGNP are the loss of vegetative cover, the successful revegetation of disturbed areas, and the 

control of non-native noxious weeds.

4.5.1 The Proposed Action 

Surface disturbance to vegetative cover would result from construction of well pads, roads, and 

pipelines. Total maximum, short-term loss of vegetative cover would be approximately 103.4 

acres of the approximately 6,400-acre project area for 12 multi-well pads plus pipeline and 

access roads (87.8 acres for 12 single well pads plus facilities) (Table 2.3). Following nearterm, post-construction reclamation and revegetation of those disturbed areas no longer subject 

to continuing use and disturbance, remaining long-term loss of vegetative cover would total 

approximately 61.9 acres for both multi-well pad facilities and single-well pad facilities. The 

maintenance of BLM standard roads comprises most of the long-term disturbance. Some 

permanent loss of vegetation cover would occur where roads are not reclaimed following the 

decommissioning of oil and gas operations in the Project Area. BLM-approved seed mixes will 

be applied to areas of disturbance following reclamation activities, including soil preparation, 

where appropriate. 

No impacts to wetlands and riparian areas are anticipated due to their absence in the Project 

Area.

There is a risk of noxious weed and invasive plant infestation under this alternative. Noxious 

weed and invasive plant establishment could result from loss of existing vegetative cover and 

soil disturbance and/or from being brought into the area by vehicles/equipment carrying soil 

material and seeds picked up in another area infested with noxious weeds. Proposed reclamation 

and revegetation/reseeding would minimize the potential for noxious weed infestation. Noxious 

weed or invasive plant species infestations, if identified in the Project Area, would be controlled 

using BLM-approved methods, as discussed in Appendix B.

4.5.2 The No Action Alternative 

There would be no additional adverse effects to vegetation from proposed additional oil and gas 

development under this alternative. However, the potential for noxious weeds or invasive plants 

to become established may result from other activities associated with existing oil and gas 

activities and ranching/grazing land uses.
Chapter 4 - Analysis of Environmental Consequences 

 4-7 

4.6 RANGE RESOURCES AND OTHER LAND USES 

4.6.1 The Proposed Action 

Anticipated impacts to range resources from implementation of the Proposed Action are 

restricted to a minimal loss of 61.9 acres of forage and associated AUMs, an increased potential 

for vehicle/livestock collisions, and an increased potential for spread of noxious and invasive 

weeds for the life of the project. The long-term loss of 61.9 acres of productive vegetation 

represents a reduction of 1.0 percent of the 6,400-acre Project Area. Livestock grazing would 

continue during the field development and operational phases of the project. Forage would be 

reduced in the short-term by a maximum of 103.4 acres until reclamation and revegetation of 

lands disturbed during drilling and construction activities are completed and a vegetative cover is 

reestablished.

Within the Project Area, the carrying capacity of the land is estimated at 9-11 acres/AUM (BLM, 

2003). Therefore, implementation of the Proposed Action would result in a maximum short-term 

productivity loss of approximately 10 AUMs and a maximum long-term productivity loss of 

approximately six AUMs. 

4.6.2 The No Action Alternative 

Under the No Action Alternative, none of the proposed field development activities would occur. 

Loss of forage for livestock and wildlife due to soil disturbance would not occur. Grazingassociated impacts would continue at their current levels. Impacts from current oil and gas 

operations would remain for the duration of production. 

4.7 WILDLIFE AND FISHERIES 

Issues relating to potential impacts to this resource from development of the Proposed Action 

were concerned with potential effects to wildlife and their habitats. 

4.7.1 The Proposed Action 

Wildlife would be affected by ground-disturbing activities, vehicle travel and drilling, and the 

presence of increased human activity and machinery operation. The area would continue to be 

available to wildlife. Big game animals would tend to move away from active construction, 

resulting in increased forage pressure on nearby areas, but tend to become habituated to facilities 

and human presence during the production phase of oil and gas projects (BLM, 2003d, pg. 4-

185). Avoidance would be reduced once the operation reaches the productive phase; however, 

levels of surface disturbance and human activity would be somewhat greater than present due to 

the increased number of wells in the Project Area (BLM, 1987, pg. 50). 

Wild horses, especially young foals and pregnant mares, could react to increased noise levels in 

the area. Wild horses, while present in the vicinity of the Project Area, are infrequent transients 

(Bargsten, 2004b, personal communication). Animals present within the area are already 
Chapter 4 - Analysis of Environmental Consequences 

 4-8 

acclimated to human presence and disturbance by local existing oil and gas developments. 

Response to development of the Proposed Action would primarily involve avoidance within the 

ample available habitat in the vicinity. 

No crucial big game winter range or birthing areas are present in this area (WGF, 2002, GIS 

data).

Short-term and long-term surface disturbance to the Project Area represent 1.4 percent to 1.6 

percent and 1.0 percent, respectively. Reduction of available forage and useable habitat is 

expected to correspond with the extent of surface disturbance planned under this alternative. 

4.7.2 The No Action Alternative 

There would be no effect to wildlife under this alternative. Livestock grazing would be expected 

to continue near its present levels. 

4.8 SPECIAL STATUS PLANT, WILDLIFE, AND FISH 

SPECIES

Issues relating to potential impacts to this resource from development of the Proposed Action 

were particularly concerned with possible effects to sage grouse and mountain plover 

populations and habitat. Concerns were also expressed regarding the possibility of disruption of 

sensitive plant communities. 

4.8.1 The Proposed Action 

4.8.1.1 Federally Listed Species 

No threatened or endangered species have been identified in the Project Area and, therefore, no 

impacts to federally listed species are anticipated. If, during construction of the Proposed 

Action, a threatened or endangered species is observed, the USFWS would be notified 

immediately. The affected area would be studied as per protocol and the appropriate mitigation 

and protective measures implemented. 

4.8.1.2 Sensitive Species 

Noise, vibrations, and construction caused by the proposed operations could cause white-tailed 

prairie dogs and other underground-dwellers to temporarily flee to their burrows while 

equipment is in close proximity. Onsite inspections have resulted in the wells being located to 

avoid burrows, where possible. Burrows were noted as being present near two of the well sites 

(12-27, 32-28). Burrows would be avoided during operations and damage (i.e., burrow failure) 

is not expected. No adverse effects to burrowing mammals are expected. 

Construction and operations would occur outside of critical time frames for certain species such 

as the mountain plover, greater-sage grouse, and raptors; sensitive species which occur or have 
Chapter 4 - Analysis of Environmental Consequences 

 4-9 

the potential to occur in the Project Area. Temporary waivers for the seasonal restrictions to 

protect sensitive species may be requested by the Operator. These waivers (“exception 

requests”) are considered on a case-by-case basis by the BLM and WGF. Approval of the 

temporary waiver requires substantiation that the resource or biota of concern are not present. 

With timing and avoidance limitations, no impacts to these species are expected. Application of 

timing limitations or avoidance measures for mountain plover, raptors, and grouse would benefit 

other sensitive species. Reduction of available forage and useable habitat is expected to 

correspond with the extent of surface disturbance planned under this alternative. 

BLM data show 20 potential raptor nest sites within or adjacent to the Project Area. Nine well 

sites lie in habitat suitable for raptors and/or raptor nesting. Ferruginous hawks are particularly 

common. Seven of the Project well sites (12-33, 14-27, 32-28, 12-27, 34-21, 12-29, Haystack 

11) lie within one mile of raptor nests identified by the BLM. At least four of the five nests 

within the Project Area have been identified as belonging to ferruginous hawks. Two well sites 

(32-32, 32-33) are situated in habitat consistent with raptor nesting and have the potential to 

contain nests.

Seven well sites (12-33, 32-33, 32-28, 12-27, 34-20, 12-29, Haystack 11) are located in habitat 

suitable for mountain plover. 

Seven of the 12 well sites surveyed exhibit possible sage grouse habitat. Five of those well sites 

(32-32, 34-29, 12-33, 32-33) lie within two miles of known sage grouse leks (breeding display 

grounds). The other two well sites (34-28, 14-27) show habitat consistent with sage grouse 

nesting/lek areas. Observations during the onsite inspection at one well site (34-28) indicated 

signs of sage grouse in its immediate area. 

Of the three special status plant species which may occur in the vicinity of the Project Area, the 

topographic limitations of two (cedar rim thistle and Gibben's beardtongue) suggests that their 

habitat, typically on sparsely vegetated slopes, is likely to fall outside of development areas. 

Similar considerations may apply to Nelson's milkvetch, although the species is also known to 

occur on alkali clay flats. None of the specific well site locations are in an area identified as 

habitat for any of these plants. 

Site-specific development COAs applying to several sensitive species are indicated in Appendix

B. Locations of raptor nests and sage grouse leks near the Project Area are indicated in Figure 

4.1

4.8.2 The No Action Alternative 

There would be no effect to special status species under the No Action Alternative. Ongoing 

production activities at existing gas wells would occur and activity from livestock grazing would 

continue.

Chapter 4 - Analysis of Environmental Consequences 

 4-11 

4.9 RECREATION 

4.9.1 The Proposed Action 

Implementation of the Proposed Action would likely cause the temporary displacement of 

hunters should drilling and construction coincide with hunting seasons for the various game 

species present in the Project Area. Displacement is expected to occur over a period of two 

hunting seasons as a result of construction and drilling activities. 

Well drilling, facilities construction, and field operations could impact both hunters and other 

users due to the additional change in the character of the landscape. Although limited oil and gas 

facilities and operations are already present in the Project Area, the addition of more wells and 

facilities will increase visual impacts and will reduce use. Use is expected to be displaced to less 

affected areas. These effects would diminish with the completion of the drilling and construction 

phase of development. Some long-term (Project life) displacement of hunters and other users 

would likely occur from implementation of the Proposed Action. The amount of hunter 

displacement would coincide with the level of game animal displacement. The Proposed Action 

is not expected to affect harvest quotas, game hunting season timing or duration, nor harvest 

success overall. 

4.9.2 The No Action Alternative 

Recreational opportunities would likely remain the same or continue to follow existing trends 

should the No Action Alternative be implemented. 

4.10 VISUAL RESOURCES 

4.10.1 The Proposed Action 

Implementation of the Proposed Action in the Project Area would add facilities and linear 

features such as roads and pipeline ROWs to an existing landscape that already supports 

facilities/features of oil and gas development, roads, and livestock grazing at a greater density 

than otherwise found in the general area. The Proposed Action would result in increased 

presence on the landscape from construction and operation of facilities and features similar in 

form, line, color, and texture to those previously introduced man-made features. Increased dust 

should also be apparent, especially during construction activities. Surface facilities at each well 

site will be painted a BLM standard environmental color to minimize contrast of colors between 

background and the proposed facilities. 

4.10.2 The No Action Alternative 

Changes to the landscape and visual resources would not occur with implementation of the No 

Action Alternative. 
Chapter 4 - Analysis of Environmental Consequences 

 4-12 

4.11 CULTURAL RESOURCES 

4.11.1 The Proposed Action 

Direct impacts to cultural resources would result from construction of well pads, roads, and 

pipelines. Class III cultural resource inventories have been conducted for all lands proposed to 

be disturbed, including drillsites, new access roads, and pipelines on a site-specific basis. All 

sites potentially eligible for listing on the NRHP will be avoided or appropriately mitigated to the 

satisfaction of the BLM. 

Effects to significant cultural resources will be alleviated either by avoidance or by data 

recovery, or by some combination of the two, as necessary. Avoidance consists of moving or 

realigning the proposed zone of construction so as to avoid significant sites or significant 

portions of sites when they are found. Avoidance is almost always the preferred plan of action. 

While data collection is the most common form of mitigation, if sites are avoided it is rarely 

necessary for project implementation. 

Heritage information within the Project Area would be affected by unanticipated discoveries of 

cultural artifacts. Every discovery results in some, unavoidable loss of cultural resource 

information. Such information loss can be partially offset by the imposition of mitigation 

measures. The effect of mitigation is that information regarding cultural resources which would 

otherwise remain unavailable would be systematically recorded. Data recovery entails 

excavation of the site, or portion(s) of the site to be impacted, in a scientific manner by a 

qualified archaeologist so as to recover the significant element(s) of the site prior to construction 

of the proposed well, access road, pipeline, etc. Prior to conducting any data recovery, a sitespecific data recovery plan must be developed and approved by the BLM in consultation with the 

SHPO.

Indirect impacts to heritage resources could occur from increased access on Project roads leading 

to illegal collection activities. Through roads are not proposed, but there may yet be an increase 

in the amount of illegal collection as a result of increased access provided by the new roads. 

New road construction would serve to connect well pads to existing roads and, while providing 

access to humans, would not add to travel through the Project Area. 

Native American resources or religious concerns have not been previously identified in the 

Project Area, but are likely present. Tribal representatives did not respond to the scoping notice 

with concerns in this area. The BLM will consult with local tribes at the project specific level if 

sensitive sites are identified as a result of the Class III Inventory. 

4.11.2 The No Action Alternative 

There would be no effect to cultural resources under the No Action Alternative. 
Chapter 4 - Analysis of Environmental Consequences 

 4-13 

4.12 SOCIOECONOMICS 

4.12.1 The Proposed Action 

The Proposed Action would be planned such that drilling equipment and personnel already 

located in the area would be utilized. It is not anticipated that an outside temporary and transient 

workforce would be required. This would alleviate impacts on housing, government services, or 

facilities. The Project workforce with disposable income would generate spending in the local 

communities resulting in sales to local businesses with associated tax benefits. 

Local sources would be used for the purchase of the materials needed by the operations 

whenever possible. There would be additional tax benefits, including property taxes on the 

capital infrastructure (ad valorem tax), gross products tax, and severance tax. 

At current rates, the cost to drill and complete each well is approximately $750,000, resulting in 

expenditures largely to the local economy of approximately $9,000,000 from construction of the 

Project. It is estimated that each of the proposed locations in the Project would recover 

approximately 4 BCFE (billion cubic feet of gas equivalent) of additional gas reserves (BLM, 

1992). These reserves would generate additional royalties and taxes to the federal government, 

State of Wyoming, and Sweetwater County. 

The United States receives a 12.5 percent royalty on the fair market value of gas produced from 

federal leases, exempting production and transportation costs. Half of federal royalties would be 

returned to the State of Wyoming. The State of Wyoming collects a six percent severance tax on 

gas production, exempting federal royalties and production and transportation costs. The state 

also collects a 4 percent sales and use tax on gross receipts of tangible goods and certain 

services. Of the funds collected, 28 percent is returned to the local county. For the Proposed 

Action, assuming 12 wells, expenditures subject to the sales and use tax are estimated to be 

approximately $3 million (BLM, 2003a, pg. 4-26). 

An estimate of these additional revenues, assuming an average gas price of $3.00/MCF over the 

life of the Project, has been indicated in Table 4.3.

Table 4.3 WDNGDP Estimated Government Revenues, Life of Project 

Revenue 

Source Payee Percentage Tax Basis 

Estimated 

Government 

Revenue 

Project royaly United States 6.25% $144,000,000 $9,000,000 

Project royalty State of Wyoming 6.25% $144,000,000 $9,000,000 

Severance tax State of Wyoming 6.0% $144,000,000 $8,640,000 

Ad valorem 

property tax 

Sweetwater County 

(55.95 mills) 

6.0% $144,000,000 $8,640,000 

Sales and use 

taxes 

State of Wyoming 2.9% $3,000,000 $87,000 

Sales and use 

taxes 

Sweetwater County 1.1% $3,000,000 $33,000 

Assumes 4 BCFE recovered/well location, $3.00/MCF constant gas price, current mill levy, project life. 
Chapter 4 - Analysis of Environmental Consequences 

 4-14 

4.13 TRANSPORTATION 

4.13.1 The Proposed Action 

Implementation of the Proposed Action would result in intermittent and short-term (two years) 

use of the county and BLM roads providing access to and within the Project Area. Traffic on 

Bar X and Tipton roads would increase primarily in daylight hours. The intensity of vehicle use 

would range widely over the two-year drilling and construction period, reflecting type and level 

of well and facilities development activity. After the wells are drilled and construction and postconstruction reclamation activities cease, traffic volume would subside as trips to and within the 

Project Area reflect reduced activity associated with routine operations by pumpers checking 

wells in pickups.

4.13.2 The No Action Alternative 

Traffic levels would remain at existing levels under this alternative. No additional road 

construction would occur in the area to provide access to new oil and gas well sites. 

4.14 HEALTH AND SAFETY 

4.14.1 The Proposed Action 

Implementation of the Proposed Action would create a higher level of risk to persons in the area. 

The increased level of traffic for the two-year drilling and construction period would increase the 

risk of traffic accidents among oil and gas workers, livestock managers, and recreationists. A 

slight increase in traffic over existing levels for the period of field operations would result in a 

proportional increase in potential for traffic accidents for the duration of field operations.

Increasing the mileage of gas gathering pipelines in the Project Area would proportionally 

increase the potential for pipeline failure. Nationally, accident rates for gas transmission 

pipelines have historically averaged 86 per year from 1994 through 1998, with fatalities 

averaging 23 per year over that five year period (USDOT, 1998, online data). During this 

period, average annual construction rates were approximately 9,200 miles. 

The risk of fire/range fire would increase in the Project Area under the Proposed Action due to 

increased activities associated with industrial, construction activities and the presence of fuels, 

storage tanks, natural gas pipelines, and other natural gas production facilities. In compliance 

with BLM requirements and as listed in Appendix B, the Proponent is committed to the 

prevention and suppression of fires on public lands caused by its employees, contractors, or 

subcontractors and to the immediate reporting of any wildland fire to the BLM. 

To minimize risks to health and safety of individuals in the WDNGP, the Proponent would 

operate in compliance with BLM, OSHA, DOT, and WOGCC. The Proponent is also committed 
Chapter 4 - Analysis of Environmental Consequences 

 4-15 

to complying with standard methods of handling any waste materials in compliance with 

methods outlined by the BLM in Appendix B. 

4.14.2 The No Action Alternative 

Implementation of the No Action alternative would result in no change to the existing health and 

safety characteristics of the area. 

4.15 NOISE 

4.15.1 The Proposed Action 

Noise associated with drilling and facilities construction over a two-year period of development 

would be increased near these operations when these individual activities occur. Drilling and 

facilities construction activities and associated increased noise levels would be temporary, lasting 

as long as the activities were ongoing at well sites and along access road and pipeline ROWs. 

EPA has established a level of 55 dBA as a guideline for acceptable environmental noise. A 

noise level of 60 dBA is generated between two people engaged in normal conversation standing 

five feet apart. Anticipated background noise levels in rural areas is anticipated to be 

approximately 40 dBA. Given that the Project Area is subject to frequent winds, the natural 

noise levels in the Project Area may approximate 50 dBA during the daylight hours (BLM, 

2003d, pg. 4-330). Wind typically adds 5 to 10 dBA. Damage to the unprotected human ear can 

occur at noise levels of 115 dBA and above (Farmingdale State University, 2004, online data). 

The 55 dBA EPA standard represents very low noise levels and indicates the level below which 

no environmental effects could reasonably be expected. 

Based on an average noise level of 85 dBA measured at 50 feet from a typical construction site, 

the expected noise levels would be 85 dBA at 50 feet, 65 dBA at 100 feet, 59 dBA at 500 feet, 55 

dBA at 1,500 feet, and 53 dBA at 2,000 feet from the construction equipment. The typical noise 

level associated with an operating drilling rig is 74 dBA at 200 feet (USGS, 1981). Noise from a 

typical drilling rig would decrease to 60 dBA at 1,000 feet, to 57 dBA at 1,500 feet, and to 54 

dBA at 2,000 feet. Therefore, an area of somewhat less than 288 acres around a typical drilling 

site would temporarily experience noise levels in excess of the EPA standard. An area of 

approximately 72 acres around each drilling location would experience temporary noise levels in 

excess of those associated with normal human conversation. The absence of any residence or 

human receptor likely to experience extended noise levels associated with oil and gas 

development under the Proposed Action minimizes potential impacts due to temporary and 

intermittent increases in noise levels for the duration of drilling and construction activity. 

Wildlife-associated impacts are also discussed in Section 4.8, including displacement and 

disturbance.

4.15.2 The No Action Alternative 

Implementation of the No Action Alternative would result in no additional noise in the Project 

Area from drilling of oil and gas wells and associated construction and operations on federal 
Chapter 4 - Analysis of Environmental Consequences 

 4-16 

lands. Noise levels would continue in response to natural conditions and ongoing human 

activity. 

4.16 CUMULATIVE IMPACTS 

Cumulative effects are those determined by summarizing the incremental impacts of an action 

added to other past, present, and reasonably foreseeable future actions in the Area of Influence 

(AOI). The AOI varies by resource. Cumulative effects can be identified both quantitatively 

and qualitatively, by magnitude of single actions, by the number of single actions combined, and 

by a time period in which the actions occur and have an effect on the environment. 

Past and existing activities on or in the vicinity of the Project Area that have a major influence on 

the resources in the area include: 

x Oil and gas exploration, production, and transport 

x Livestock grazing activities (including fences, stock watering facilities, etc.) 

x Recreation activities, principally hunting 

Responses to the scoping notice for the Proposed Action expressed concerns relating to the

cumulative effects of natural gas development activities when combined with other ongoing and 

proposed developments on lands within the BLM Rawlins Field Office area. 

Increasing natural gas prices, geophysical exploration requests, and oil and gas development 

trends suggest that further environmental impacts in the Great Divide Basin would occur from oil 

and gas development, including potential CBNG development. Large increases in grazing and 

recreational pressures are not foreseen. Therefore, this discussion will focus on the effects of 

additional oil and gas development. 

Existing petroleum fields located within six miles of the Project Area, all of which produce gas 

and condensate, are indicated in Table 4.4.

Table 4-4 Existing Oil and Gas Fields Near the WDNGDP 

Field Reservoir(s) Discovery Completed 

Wells

APDs and 

Spuds

Hay Reservoir Lance, Lewis, Almond, Mesaverde 1977 61 4 

Bush Lake Lance, Lewis, Almond, Mesaverde 1978 ABD 0 

Nickey Lewis, Almond 1980 2 0 

Gale Lewis, Ericson 1980 2 0 

Great Divide Lance, Lewis 1978 9 0 

Red Desert Lewis, Mesaverde 1971 27 3 

Lost Creek Basin Lewis, Ericson, Mesaverde 1976 0 0 

Source: WOGCC (2004). ABD indicates abandoned field. 

The BLM is analyzing a number of potential oil and gas development projects within the Great 

Divide Basin. These projects are summarized in Table 4.5.
Chapter 4 - Analysis of Environmental Consequences 

 4-17 

Table 4.5 Potential Oil and Gas Development Projects, Great Divide Basin 

Name Reservoir Proposed

Wells Status

Continental 

Divide/Wamsutter II 

Natural Gas Project 

Almond, Lewis, 

Mesaverde

3,000 EIS ROD signed 2000. 

Approximately half of the analysis 

area covers the Great Divide Basin. 

Located directly south of the Project 

Area. 2,130 wells authorized 

pending planning review of the 

Great Divide Resource Area RMP 

by the Rawlins Field Office. 

Wind Dancer Natural 

Gas Development 

Project 

Lance, Lewis, 

Mesaverde

12 Analysis area of 6,400 acres. EA in 

preparation. Comprises the Project 

Area.

Hay Reservoir CBNG Ft. Union 8 Analysis area of 1,280 acres. EA in 

preparation. Six miles south of 

Project Area. 

Lower Bush Creek 

CBNG

Ft. Union 20 EA in preparation, 20 producing 

wells plus 2 injection wells. 7-10 

miles northwest of Project Area. 

Hay Reservoir Natural 

Gas Infill Drilling 

Almond, Lewis 25 EA in preparation. Adjoins Project 

Area on the west. 

Scotty Lake CBNG Ft. Union 18 EA for pilot project, 18 wells over 

3,000 acres, 3 current producing 

from re-entries. 12 miles north of 

Project Area. 

Source: BLM Rawlins Field Office (2004). 

In addition to the above drilling projects, the BLM Rawlins Field Office is considering or has 

approved three geophysical projects within the vicinity of the Project Area, the Hay Reservoir 

3D Seismic Survey, the Osborne Springs 3D Seismic Survey, and Wind Dancer 3D/2D Seismic 

Survey projects. 

4.16.1 Geology, Minerals, and Paleontology 

The AOI for geology, minerals, and paleontology would be the Project Area. 

Existing, proposed, and reasonably foreseeable actions would not add to the level of geological 

hazards in the Project Area. 

Existing and foreseeably developable mineral resources within the vicinity of the Project Area 

are restricted to oil and gas development. Development of oil and gas resources would result in 

minor alterations to the existing topography. The bulk of these resources within the vicinity of 

the Project Area would be developed on BLM surface or minerals and would require adherence 

to BLM reclamation stipulations. Standard stipulations, augmented by site-specific COAs, 

would effectively mitigate minor levels of topographic disturbance. 

Ongoing development would have the potential to negatively impact paleontological resources. 

However, BLM requirements for the protection of such resources would effectively mitigate 
Chapter 4 - Analysis of Environmental Consequences 

 4-18 

potential losses of fossil information. Net effects to paleontological resources are expected to be 

positive, with the potential for discoveries of significant fossils resulting from development. 

4.16.2 Air Quality 

The AOI for air quality would encompass the Great Divide Basin. Cumulative effects of 

development to air quality could conceivably affect a larger area than for any other resource. 

Ongoing development of oil and gas resources within the Great Divide Basin would negatively 

impact air quality through increased criteria pollutant emissions associated with machinery 

engines and compressors, as well as from fugitive dust resulting from increased developmentassociated vehicular traffic. Most of the effects from seismic surveys would be limited to 

increases in fugitive dust emission. Cumulative impacts from the Proposed Action would be 

similar to those analyzed for the Continental Divide/Wamsutter II Natural Gas Project EIS 

(BLM, 2000) and the Desolation Flats Natural Gas Field Development Project FEIS (BLM, 

2004). The Proposed Action would be responsible for relatively lower levels of emissions since 

additional compression is not planned. 

As discussed in Section 4.2.1, previously, air quality modeling for the Desolation Flats FEIS 

suggests that air impacts from the Proposed Action would be below applicable federal and state 

standards. The Project would represent a very small fraction of emissions resulting from 

increased oil and gas development within the Great Divide Basin. As detailed in Section 4.2, 

there will be small but measurable effects in the immediate Project Area, small but measurable 

effects in the near field, and this project will incrementally contribute to a reduced far field 

visibility effect. 

Cumulative air quality impacts would include emissions from nearby oil and gas production, 

such as the adjacent Hay Reservoir Unit. Disturbances associated with such fields will decline 

over time. At Hay Reservoir, 16 wells have been abandoned and reclaimed, reducing 

disturbance levels. Modernization of facilities, including replacement of numerous, small 

compressors with three modern, lean-burning Western Gas compressors, has also acted to reduce 

overall emissions levels (WOGCC, 2004, online data; Webb, 2004, personal communication). 

4.16.3 Soils 

The AOI for soils consists of the Project Area, including five existing and 12 proposed wells and 

ancillary facilities.

Cumulative soils impacts from past, present, and reasonably foreseeable activities combined with 

the Proposed Action would consist principally of soil impacts from on-going oil and gas 

production and exploration and development activities, continuing livestock management 

activities, and seasonal recreational/hunting activities. The drilling of approximately 12 wells 

and associated construction of ancillary facilities including roads and pipelines would contribute 

both short-term and long-term impacts in the form of soil disturbance for the life of the oil and 

gas projects. Total long-term cumulative surface disturbance would be approximately 63 acres. 

In combination with appropriate livestock use, off-road vehicle activity, primarily during hunting 
Chapter 4 - Analysis of Environmental Consequences 

 4-19 

seasons; implementation of standard stipulations and site-specific construction and reclamation 

procedures for oil and gas facilities would minimize the cumulative impacts to soils. 

4.16.4 Water Resources 

The AOI for surface water resources would be limited to several local watersheds in the vicinity 

of the Project Area. These include the Red Creek-Rocky Crossing watershed, comprising 

approximately 24,000 acres along Red Creek on the north side of the Project; the Red CreekCronin Draw watershed, comprising approximately 12,000 acres along lower Red Creek to the 

west and southwest; and the Lower Lost Creek - Lost Creek watershed to the south and 

southeast, comprising more than 61,000 acres around and southeast of Lost Creek dry lake. 

CBNG development at Scotty Lake, within the Red Creek watershed to the north of the Project 

Area, could contribute produced water to the Red Creek drainage, if surface discharge is used for 

disposal. The project is a pilot development consisting of 18 potential wells. Volumes of 

produced water are anticipated to be small (less than 3 cfs), and it is likely that infiltration would 

prevent any discharge from reaching the Project Area. The Kennedy Hay Reservoir CBM pilot 

to the south is located within the North Red Desert Basin watershed, which is isolated from the 

Red Creek watershed, and would not contribute to cumulative impacts. All streams within the 

Great Divide Basin are internally drained and waters of the Colorado River System would not be 

affected. Neither the Wind Dancer nor the Hay Reservoir conventional gas development projects 

would cause additional effects to surface water since no surface discharge is proposed for either. 

The same situation is true for other gas fields located within watersheds located adjacent to the 

Project Area, including the Nickey and Gale fields.

As indicated in Section 4.4.1, impacts to surface water from the Proposed Action would be 

limited to some short-term erosion as a result of increased run-off from roads and well pads. 

There would be some resulting soil deposition into small intermittent drainages. Mitigation 

measures would be implemented to reduce these impacts. Therefore, no cumulative effects to 

surface water resources are anticipated for this alternative. 

The AOI for groundwater resources would be the Great Divide Basin.

As discussed in Section 3.4.2 previously, groundwater flow is generally toward the basin center, 

which is located near the Project Area. CBNG developments could impact groundwater 

resources through withdrawal of groundwater and/or infiltration of produced water if surface 

discharge is used for disposal. The Scotty Lake, Lower Bush Creek, and Hay Reservoir CBNG 

pilots total 46 proposed wells. Potential volumes of produced water are unknown and disposal 

methods are undetermined at this time, precluding a more quantitative estimated of potential 

groundwater effects.

As discussed in Section 4.4.1 previously, the Proposed Action would not cause impacts to 

groundwater resources since no surface discharge is planned and no infiltration would result. 

Any Project produced water would be trucked from the location to an approved disposal site not 

located on federal surface. Required drilling, completion, and stimulation practices would 
Chapter 4 - Analysis of Environmental Consequences 

 4-20 

protect aquifers from damage from wellbores or cross-contamination between aquifers. No 

cumulative effects are anticipated for this alternative. 

4.16.5 Vegetation, Wetlands, and Noxious Weeds 

The AOI for vegetation consists of the Project Area, including five existing and 12 proposed 

wells and ancillary facilities. 

Cumulative impacts on vegetation from past, present, and reasonably foreseeable activities 

combined with the Proposed Action would consist principally of loss of vegetative cover and 

opportunities for noxious weed infestation from on-going oil and gas production and exploration 

and development activities, continuing livestock management activities, and seasonal 

recreational/hunting activities. The drilling of approximately 12 wells and associated 

construction of ancillary facilities including roads and pipelines, in addition to disturbances 

associated with five existing wells and facilities, would contribute both short-term and long-term 

impacts in the form of loss of vegetative cover for the life of the oil and gas projects. Total 

cumulative long-term surface disruption would be approximately 63 acres. In combination with 

appropriate livestock use and off-road vehicle activity, primarily during hunting seasons; 

implementation of standard stipulations and site-specific construction and reclamation 

procedures for oil and gas facilities would minimize the cumulative impacts to vegetation and 

would minimize potentials for weed infestation and spread. 

4.16.6 Range Resources and Other Land Uses 

The AOI for range resources consists of the Cyclone Rim Allotment area of approximately 

308,000 acres.

Cumulative impacts on livestock and big game management from past, present, and reasonably 

foreseeable activities combined with the Proposed Action would consist principally of the 

previously described loss of vegetative cover, increased potential for noxious weed infestation, 

and subsequent reduction in available forage. These impacts would result from on-going oil and 

gas production and exploration and development activities, and to a lesser degree the continued 

grazing of lands and use for recreational hunting. The drilling of approximately 12 wells and 

associated construction of ancillary facilities including roads and pipelines, in addition to 

disturbances associated with five existing wells and facilities, would contribute both short-term 

and long-term impacts in the form of loss of vegetative cover and forage for the life of the oil 

and gas projects. Total cumulative long-term surface disruption would be approximately 63 

acres. Existing oil and gas development within the Cyclone Rim Allotment is approximately 147 

wells (WOGCC, 2004a, GIS data). As discussed in Section 4.16.7, average per well long term 

surface disturbance for oil and gas development within the Great Divide Basin averages 

approximately 4.9 acres/well. Three foreseeable oil and gas projects occur within the Cyclone 

Rim Allotment, the Hay Reservoir and Scotty Lake CBNG projects and the Hay Reservoir Unit 

Natural Gas Infill Drilling Project, totaling 51 wells. Therefore, planned, existing, and 

foreseeable long-term surface disturbance within the Cyclone Rim Allotment from oil and gas 

development is approximately 1,033 acres. Based upon the estimated carrying capacity of the 

land in the Project Area of 9-11 acres per AMU, cumulative long-term effects are estimated at 
Chapter 4 - Analysis of Environmental Consequences 

 4-21 

approximately 103 AUMs. This represents approximately 0.3 percent of the total of the 40,661 

AUMs in the allotment (Bargsten, 2004a, personal communication). In combination with 

appropriate livestock use and off-road vehicle activity, primarily during hunting seasons, 

implementation of standard stipulations and site-specific construction and reclamation 

procedures for oil and gas facilities would minimize the cumulative impacts to forage 

availability.

4.16.7 Wildlife and Fisheries 

The AOI for wildlife species would vary greatly in extent. Small, terrestrial mammals would not 

travel far from current habitat and impacts would be restricted to the Project Area. Big game 

species have the capability of roaming over much greater areas. For this EA, varying AOIs have 

been selected, as indicated in Table 4.6.

Table 4.6 Areas of Influence Used for Cumulative Impacts Analysis 

Species Area of Influence Rationale 

Big game WGF herd unit Potential range of herd 

Raptors Project Area + 1 mile buffer Current nest stipulation 

Sage grouse Project Area + 2 mile buffer Current lek stipulation 

Other birds Project Area + 1 mile buffer Based on raptor stipulation 

Smaller mammals Project Area Limited mobility for smaller 

species 

Aquatics Streams and wetlands in project 

vicinity 

Not present this project 

Sensitive plants Project Area Limited mobility, habitat 

Cumulative impacts to wildlife may result from harassment resulting from increased human 

access and presence, destruction of forage, increased mortality from collisions with vehicles, and 

fragmentation of habitat. The low levels of surface disturbance associated with most 

conventional oil and gas development projects would not necessarily guarantee a negligible level 

of impacts to wildlife. Several proximal projects occurring simultaneously could magnify the 

effects of the individual developments by hindering the ability of wildlife to relocate away from 

individual sources of disturbance.

Because of the size and range of herd units in the Great Divide Basin, cumulative impacts 

analysis required investigation of foreseeable oil and gas development projects on BLM land in 

areas under the jurisdiction of the Rock Springs and Lander field offices. The levels of surface 

disturbance from existing oil and gas development over the extent of each herd unit was 

estimated, based upon long-term disturbance information from recent NEPA analyses. No 

current or foreseeable projects from the Lander Field Office coincide with Project big game herd 

units. Two current projects from the Rock Springs Field Office with approximately 116 acres of 

long-term disturbance were included. For the Rawlins Field Office, the projects listed in Table

4.5 were included, with the assumption that approximately half of the wells authorized under the 

Continental Divide/Wamsutter II Natural Gas Project would be located within the Great Divide 

Basin. A further assumption was that each location would contain a single wellbore, which is 

likely to be correct in most cases. Based upon all of the data, long-term disturbance from 
Chapter 4 - Analysis of Environmental Consequences 

 4-22 

foreseeable oil and gas development within the extent of Project herd units was estimated to 

approximate 4.9 acres/well for approximately 1,235 wells, for a total foreseeable impact of 

approximately 5,750 acres. 

The Proposed Action would likely result in minimal impacts to the elk population as elk are 

infrequent visitors to the vicinity of the Project Area (WGF, 2002, GIS data). The local elk 

population belongs to the 2.5 million acre Herd Unit Area 426 (Steamboat). Within the 

Steamboat Herd Unit Area, elk are mainly concentrated within the central region, whereas the 

Project Area occupies the center of a large (700,000 acres) area of infrequent visitation to the 

east. The nearest crucial winter/year-long range occurs in a 25,000 acre area located 

approximately six miles to the southwest. Within the Steamboat herd unit, existing oil and gas 

development includes approximately 1,103 wells (WOGCC, 2004a, GIS data). At an average 

long-term disturbance of 4.9 acres/well, plus 5,750 acres of foreseeable disturbance, total 

existing and foreseeable disturbance would be approximately 11,150 acres. Project long-term 

disturbance of 62 acres represents 0.6% percent of the existing and foreseeable disturbance. 

The entire vicinity of the Project Area, and almost all of the 2.16 million acre Herd Unit Area 

615 (Red Desert), comprises antelope winter/yearlong range. Antelope move freely over the 

area and have forage options beyond disturbance areas. Crucial winter range is located only 

along the southern eastern margins of the Herd Unit Area, more than 20 miles beyond the Project 

Area (WGF, 2002, GIS data). Impacts are not anticipated. Within the Red Desert herd unit, 

existing oil and gas development includes approximately 1,512 wells (WOGCC, 2004a, GIS 

data). At an average long-term disturbance of 4.9 acres/well, plus 5,750 acres of foreseeable 

disturbance, total existing and foreseeable disturbance would be approximately 13,150 acres. 

Project long-term disturbance of 62 acres represents 0.5 percent of the existing and foreseeable 

disturbance.

The local mule deer population belongs to the 2.5 million acre Steamboat Herd Unit Area. Mule 

deer are infrequent visitors to the Project Area, with the exception of identified 

spring/summer/fall range in the area immediately around and southwest of Hay Reservoir. This 

local population inhabits a 27,000 acre area near the center of an infrequent visitation range of 

approximately one million acres extent (WGF, 2002, GIS data). The nearest crucial winter range 

is located more than 30 miles to the west. Oil and gas development from the Proposed Action, 

the Hay Reservoir Natural Gas Infill Drilling Project, and the Kennedy Hay Reservoir CBM 

Pilot would occur within the approximate 42 square mile area of spring/summer/fall mule deer 

range. Approximately 53 existing, and an estimated 29 proposed wells would be located within 

this range. Based upon average long-term disturbance levels for the Proposed Action of 

approximately 3.7 acres per well location, total long-term cumulative impact from existing and 

proposed oil and gas development would be approximately 303 acres, or approximately one 

percent of the local mule deer range. Within the entire Steamboat herd unit, existing oil and gas 

development includes approximately 1,265 wells (WOGCC, 2004a, GIS data). At an average 

long-term disturbance of 4.9 acres/well, plus 5,750 acres of foreseeable disturbance, total 

existing and foreseeable disturbance would be approximately 11,950 acres. Project long-term 

disturbance of 62 acres represents 0.5 percent of the existing and foreseeable disturbance. 
Chapter 4 - Analysis of Environmental Consequences 

 4-23 

CBNG pilot developments near the Project Area are probably too remote to add to wildlife 

effects for most terrestrial species from the Proposed Action, other than big game populations. 

The Hay Reservoir Natural Gas Infill Drilling Project, located immediately adjacent to the 

Project Area, and which is likely to be constructed more or less simultaneously with the 

Proposed Action, could potentially magnify the effects of surface disturbance. Cumulative longterm surface disturbance from existing and proposed wells and ancillary facilities within the 

Project area is approximately 124 acres, or 1.9 percent of the Project Area.

4.16.8 Special Status Plant, Wildlife, and Fish Species 

The cumulative impacts areas of influence for certain sensitive species are indicated in Table 

4.6.

An active sage grouse lek is located immediately adjacent to the Project Area and eight leks have 

been identified within 10 miles. Fifteen existing wells and ancillary facilities are located in a 

two mile buffer around the Project Area, with an approximate long-term surface disturbance of 

78 acres. An estimated 7 future wells are likely to be drilled within two miles of the Project Area 

within the Hay Reservoir Unit, with an estimated long-term disturbance of approximately 36 

acres. Total long-term surface disturbance from existing and foreseeable oil and gas 

development within the Project Area and a two mile buffer is approximately 238 acres, or 0.8 

percent of the area. 

The situation for raptors, principally ferruginous hawks, is similar to that for sage grouse. 

Numerous nests have been identified within the general vicinity of the Project Area. Stipulations 

on development imposed by BLM would act to protect raptors Three existing wells and 

ancillary facilities are located in a one mile buffer around the Project Area, with an approximate 

long-term surface disturbance of 16 acres. An estimated one future well is likely to be drilled 

within one mile of the Project Area within the Hay Reservoir Unit, with an estimated long-term 

disturbance of approximately five acres. Total long-term surface disturbance from existing and 

foreseeable oil and gas development within the Project Area and a two mile buffer is 

approximately 145 acres, or 0.9 percent of the area. 

Fish species are not known from the vicinity of the Project Area and Red Creek, which crosses 

the western edge of the Project Area, is a Class 4 stream. 

The habitat for sensitive plant species which may occur in the Project Area is likely to be outside 

of the locations of most oil and gas facilities. Cumulative long-term surface disturbance from 

existing and proposed wells and ancillary facilities within the Project area is approximately 124 

acres, or 1.9 percent of the Project Area. The required application of existing USFWS and BLM 

mitigation measures is expected to reduce any potential impacts to sensitive plant species which 

may occur in the Project Area. 

4.16.9 Recreation 

The AOI for recreational resources would include the Project Area and a surrounding buffer 

area. The buffer would encompass an area in which certain wildlife species, notably big game 
Chapter 4 - Analysis of Environmental Consequences 

 4-24 

and raptors, could be temporarily displaced by, principally, construction and drilling activities. 

The size of the buffer is estimated to be a maximum of two miles. Total long-term surface 

disturbance from existing and foreseeable oil and gas development within the Project Area and a 

two mile buffer is approximately 238 acres, or 0.8 percent of the area, as discussed in Section 

4.16.8.

Cumulative impacts of implementing the WDGNDP in combination with past, present, and 

reasonably foreseeable activities would affect recreational activities within the Project Area and 

beyond. Within the Project Area, the addition of roads to the existing network would facilitate 

roaded travel for recreationists/hunters to more parts of the Project Area. Disturbance from 

operations and construction may temporarily displace game animals and hunters. This 

displacement would be short-term. 

4.16.10 Visual Resources 

The AOI for visual resources would be areas within visual range of the Proposed Action, 

principally an area within approximately one mile of the Project Area. 

As previously discussed in Section 3.10, existing visual qualities in the WDNGDP and adjacent 

lands have already been affected by ongoing oil and gas development, including road building 

and pipeline construction, Livestock management and recreational uses have also contributed 

less noticeable features to the visual quality of the Project Area and adjacent lands including 

fences and off-road tracks in addition to use of the existing road network. The Proposed Action 

along with ongoing and proposed oil and gas projects in and adjacent to the Project Area would 

add to the level of impact to visual resources in the immediate area. However the added features 

of the WDNGDP would be consistent with the existing well site, roads, and reclaimed pipeline 

features in line, form, color, and texture; and would still be consistent with the current VRM 

Class 3 designation with implementation of standard best management practices for all oil and 

gas projects including specifically the mitigation measures proposed in Chapter 2 and Appendix 

B of this EA. Cumulative impacts on visual resources are expected to occur. 

4.16.11 Cultural Resources 

The AOI for cultural resources is the Project Area. 

Provisions of the National Historic Preservation Act and other regulations require identification 

and protection of heritage resources on public lands. In compliance with these requirements, oil 

and gas operators have conducted or would conduct archeological inventories prior to 

development. Cultural sites would be identified and in most cases avoided. Where avoidance is 

impossible, mitigation measures would protect or recover information about the site. The 

completion of these inventories would result in an increase in heritage information and a 

beneficial impact.
Chapter 4 - Analysis of Environmental Consequences 

 4-25 

4.16.12 Socioeconomics 

The AOI for socioeconomics is Sweetwater and Carbon counties, including the communities of 

Rawlins, Rock Springs, and Wamsutter. 

With the completion of several programmatic NEPA analyses covering oil and gas development 

in the Green River, Great Divide, and Washakie basins, southwestern Wyoming is likely to 

experience an increase in the levels of natural gas development activities. 

As discussed in Section 3.12 previously, both counties and the municipalities of Rock Springs 

and Rawlins have experienced net population losses over the last decade. This suggests that 

municipal infrastructures would be able to accommodate any limited and temporary population 

increases associated with initial phases of expanded oil and gas development, including the 

Proposed Action. Should economic conditions continue to favor development, it is possible that 

infrastructure upgrades would be required by local governments and housing shortages could 

occur. The community of Wamsutter has experienced a nearly 9 percent population growth in 

the last decade, potentially resulting in local housing shortage. However, the very small size of 

the town (261, 2000 census) and the availability of temporary housing units suggest that initial 

phases of expanded gas development would have minor negative impacts to Wamsutter. 

Ongoing and expanded gas development in southwestern Wyoming could affect the attitudes of 

local populations by visually altering the landscape and possibly displacing recreational 

opportunities.

Overall, the Proposed Action and other currently-active gas development projects would have a 

beneficial effect on government revenues, local employment, and local merchandising. 

4.16.13 Transportation 

The AOI for transportation issues would include the I-80 corridor and roads reaching the vicinity 

of the Project Area from I-80, principally Bar X, Tipton, and Luman roads. 

These roads provide adequate capacity for existing uses, principally recreational hunting and 

livestock ranching in addition to oil and gas production. Foreseeable increases in natural gas 

development could result in higher maintenance requirements for gravel-surfaced roads north of 

I-80. Large increases in oilfield traffic associated with oil and gas development in both the Great 

Divide Basin to the north and the Washakie Basin to the south could result in increased 

maintenance requirements for I-80. 

4.16.14 Health and Safety 

The AOI for health and safety issues would be similar to that for transportation, described in 

Section 4.16.13.

The most likely sources of risks to human health and safety are anticipated to be from potential 

industrial accidents associated with drilling and completion activities and pipeline construction, 
Chapter 4 - Analysis of Environmental Consequences 

 4-26 

and from potential vehicular accidents associated with increased traffic on Project access routes. 

Cumulative impacts are expected to be those described for the Proposed Action.

4.16.15 Noise 

The AOI for noise would be the Project boundary plus a 2,000 foot buffer, which would 

encompass the area within which noise during drilling operations would exceed the EPA 

standard, as discussed in Section 4.15.1.

No cumulative effects from noise above or beyond those discussed in Section 14.15.1 are 

expected.
 5-1 

CHAPTER 5 - CONSULTATION AND 

COORDINATION 

5.0 CONSULTATION AND COORDINATION 

This EA was prepared by a third-party contractor working under the direction of, and in 

coordination with, the Bureau of Land Management's Rawlins, Wyoming Field Office. During 

the preparation of this EA, the preparers have consulted with representatives of, or otherwise 

obtained information from, the following governmental agencies: 

State of Wyoming, Department of Administration and Information, Division of Economic 

Analysis

State of Wyoming, Department of Environmental Quality 

State of Wyoming, Game and Fish Department 

State of Wyoming, Oil and Gas Conservation Commission 

State of Wyoming, State Historic Preservation Office 

State of Wyoming, State Engineer’s Office 

U.S. Bureau of Land Management, Rawlins, Wyoming Field Office 

U.S. Census Bureau 

U.S. Department of Agriculture, Natural Resources Conservation Service 

U.S. Department of Transportation 

U.S. Fish & Wildlife Service, Ecological Services Office 

U.S. Geological Survey 

5.1 PUBLIC PARTICIPATION 

As part of the preparation of an Environmental Assessment, the Council on Environmental 

Quality (CEQ) requires (40 CFR 1500-1508) an initial public scoping process to assist in the 

determination of issues of concern and provide information to be used in the selection of 

potential alternatives to the Proposed Action. 

A scoping notice was prepared by BLM and submitted to the public on February 17, 2004. The 

notice was sent to all individuals, agencies, companies, and organizations listed on the BLM's 

NEPA mailing list. The 30 day public comment period ended March 17, 2004. Comments were 

received from the following individuals, agencies, or organizations: 

Biodiversity Conservation Alliance / Wyoming Outdoor Council 

Carbon County Economic Development Corporation 

Laura Lindley 

Joe Sachen 

B.J. Tyler 

Petroleum Association of Wyoming 

State of Wyoming, Department of Game and Fish 

State of Wyoming, Department of Environmental Quality 

State of Wyoming, Office of State Lands and Investments 
Chapter 5 - Consultation and Coordination 

 5-2 

State of Wyoming, State Historic Preservation Office 

U.S. Department of Agriculture Natural Resources Conservation Service 

U.S. Fish and Wildlife Service 

U.S. Forest Service, Bridger-Teton National Forest 

5.2 LIST OF PREPARERS 

U.S. Bureau of Land Management, Rawlins, Wyoming Field Office 

Travis Bargsten, Natural Resources Specialist and ID Team Leader 

Mike Calton, Rangeland Management Specialist 

Lloyd Chism, Petroleum Engineer 

Krystal Clair, Recreation Planner 

Heath Cline, Wildlife Biologist 

Bill Falvey, Wildlife Biologist 

Susan Foley, Soils Scientist 

Mike Jensen, District Engineer 

Mark Newman, Geologist 

David Simons, Environmental Planner 

Chuck Valentine, Realty Specialist 

Patrick Walker, Archaeologist 

Banko Petroleum Management, Inc. (Third-Party Contractor) 

David Banko, P.E., Project Manager 

Dana Consultants (Subcontractor) 

Keith Dana, Range and Wildlife Consultant 

O&G Environmental Consulting, LLC (Subcontractor) 

Richard Bell, Soils Scientist and NEPA Specialist 

Joe Fetzer, P.G., Geologist 

Chris Gayer, Wildlife Biologist 

Ethan Jahnke, Hydrologist and GIS Specialist 

Matt Santo, Wildlife Biologist 

Bea Van Horn, Documents Coordinator 

Western Archeological Services (Subcontractor) 

Jana Pastor, Archaeologist 
 R-1 

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Specialist.

Bill Barrett Corporation. 2004. Big Porcupine CBM Project Environmental Assessment, 

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District.

Bills, Tom. 2004. Personal Communication from Tom Bills Regarding West Nile Virus and 

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2004.

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Wyoming. Wyoming State Geological Survey, Open File Report 87-9, September 15, 1987. 

Case, James C. and J. Annette Green. 2000. Earthquakes in Wyoming, Wyoming State 

Geological Survey, Information Pamphlet 6. 

Cotterman, . 2004. Personal Communication with Jim Cotterman, April, 2004, Sweetwater 

County Weed and Pest District, Farson, Wyoming. 

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http://www.wrds.uwyo.edu/wrds/wsc/climateatlas/title_page.html, May 2, 2004. 

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Project, Western Archaeological Services, Rock Springs, Wyoming. 

de Bruin, Rodney. 2002. Oil and Gas Map of Wyoming, Wyoming State Geological Survey, 

Map Series 55. 
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Osborn and R. C. Hassler, I & O Publishing, Omaha, Nebraska. 

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2004.

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Newman, Mark. 2004. Personal Communication on May 12, 2004 with Mark Newman 

Regarding Geological and Paleontological Aspects of Wind Dancer EA, BLM Rawlins Field 

Office Geologist. 
References

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Pastor, Jana. 2004. Personal Communication on May 25, 2004 with Jana Pastor, Consulting 

Archaeologist, Regarding Wyoming State Historic Preservation Office Cultural Records Search, 

Wind Dancer Natural Gas Development Project, Western Archaeological Services. 

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online data, retrieved from http://www.sweda.net/index.htm, May 4, 2004. 

Thompson, K. W., and J. V. Pastor. 1995. People of the Sage: 10,000 Years of Occupation in 

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of Western Wyoming College, Rock Springs, Wyoming. 

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Plan Environmental Impact Statement, Rawlins, Wyoming, Field Office. 

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Approved Resource Management Plan, Rawlins, Wyoming, Field Office. 

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Environmental Assessment, Rawlins, Wyoming, Field Office. 

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Resource Management. 

U.S. Bureau of Land Management. 2000. Record of Decision and Environmental Impact 

Statement Continental Divide/Wamsutter II Natural Gas Project, Rawlins and Rock Springs, 

Wyoming, Field Offices. 

U.S. Bureau of Land Management. 2002. BLM Wyoming Sensitive Species and Policy List, 

U.S. Bureau of Land Management. 14 pp. Cheyenne, Wyoming. Retrieved from: 

http://www.wy.blm.gov/wildlife/02species.pdf

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and the United States, Bureau of Land Management Wyoming State Office, Cheyenne, 

Wyoming. 

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Coalbed Methane Project, Brown Cow POD, Carbon Co. Wyoming, Rawlins, Wyoming, Field 

Office.

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Environmental Impact Statement. BLM Buffalo Field Office. Buffalo, Wyoming. 

U.S. Bureau of Land Management. 2004. Final Environmental Impact Statement, Desolation 

Flats Natural Gas Field Development, Rock Springs and Rawlins, Wyoming, Field Offices. 

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Appendix A 

Approvals and Authorizing Actions
Wind Dancer Natural Gas Development Project A-1 Approvals an

Appendix A: Approvals and Authorizing Actions Necessary for Construction, Operation, MaintAbandonment of the Proposed Action 

Issuing Agency/Permit Nature of Permit Authority Applicab

FEDERAL PERMITS, APPROVALS AND AUTHORIZING ACTIONS U.S. Bureau of Land Management Permit to Drill, Deepen or Plug Back (APD Process) 

Controls drilling for oil and gas on federal onshore leases 

Mineral Leasing Act of 1920 (30 U.S.C. 181 et seq.) 

Well pad cand compl

Approval of Unitization Provides for efficient and timely 

development and production of federal oil and gas leases 

Mineral Leasing Act of 1920 (30 U.S. C. 181 et seq.); 43 CFR 3180 

Wind Danc

Rights-of-way Grants and Temporary Use Permits 

Right-of-way grants on BLMmanaged lands Mineral Leasing Act of 1920 (30 U.S.C. 181 et seq.) Pipelines o

Rights-of-way Grants and Temporary Use Permits 

Right-of-way grants on BLMmanaged lands Federal Land Policy and Management Act of 1976 (43 U.S. 

C. 1761-1771); 43 CFR 2800 

Access roalands 

Antiquities and Cultural Resources Permits 

Issue antiquities and cultural resources use permit to excavate or remove cultural resources from federal lands 

Antiquities Act of 1906 (16 U.S. C. Sections 432-433); Archaeological Resources Public Protection Act of 1979 (16 U.S.C. Sections 470aa-47011); 43 CFR Part 3 

All proposecomponen

Approval to dispose of produced water

Controls disposal of produced water from federal leases 

Mineral Leasing Act of 1920 (30 U.S.C. 181 et seq.); 43 CFR 3160 

Wells 

U.S. Department of the Army (Corps of Engineers) Section 404 Permit (nationwide) Controls placement of dredged or 

fill material in Waters of the U.S. including adjacent wetlands 

Section 404 of the Clean Water Act of 1972 (40 CFR 122-123) 

Pipeline anstreams 

U.S. Fish and Wildlife Service Consultation Process, Endangered or Threatened Species 

Preliminary Biological Assessment Section 7 of the Endangered 

Species Act of 1973, as amended (16 U.S.C. et seq.) 

All surface 
Wind Dancer Natural Gas Development Project A-2 Approvals an

Issuing Agency/Permit Nature of Permit Authority Applicab

STATE PERMITS, APPROVALS AND AUTHORIZING ACTIONS Wyoming Department of Environmental Quality - Water Quality Division (WDEQ-WQD) Water Quality Permit Regulate disposal of drilling fluids 

from abandoned reserve pits 

Wyoming Environmental Quality Act, Article 3, Water Quality, as amended (W.S. 35-11-301 through 35-11-311) 

Reserve p

SWPP Permit NPDES permits for discharging 

produced water and stormwater runoff

WDEQ-WQD Rules and Regulations, Chapter 18; Wyoming Environmental Quality Act, Article 3, Water Quality, as amended (W.S. 35-11-301 through 35-11-311); Section 405 of the Federal Water Pollution Control Act (Clean Water Act)(codified at 33 U.S.C. 1345) 

Well pads 

Hydrostatic Discharge Permit Administrative approval for 

discharge of hydrostatic test water 

Wyoming Environmental Quality Act, Article 3, Water Quality, as amended (W.S. 35-11-301 through 35-11-311) 

Pipelines

Water Quality Permits Temporary sewage facilities (W.S. 

35-11-301 through 35-11-307) 

Wyoming Environmental Quality Act 

Temporary 

Wyoming Department of Transportation Oversize and Overlength Load Permits 

Permits for oversize, overlength and overweight loads regulations 

Chapters 17 and 20 of the Wyoming Highway Department Rules 

Transportamaterials o

Wyoming Oil and Gas Conservation Commission Gas Flaring Permit Authorization for flaring or venting 

of gas 

WOGCC Regulations, Chapter 3, Operational and Drilling Rules, Section 45 Authorization for Flaring or Venting of gas 

Wells 
Wind Dancer Natural Gas Development Project A-3 Approvals an

Issuing Agency/Permit Nature of Permit Authority Applicab

Injection of Produced Water Permit for Class II underground 

injection wells 

Underground Injection Control Program: Criteria and Standards, as amended (40 C.F.R. 146); state Underground Injection Control Programs, Stateadministered program - Class II Wells, as amended (40 C.F. R. 147.2551) 

Wells 

Plugging Abandoned Wells Well plugging and abandonment WOGCC Regulations, Chapter 3, 

Section 14, Reporting (Form 4); Section 15, Plugging of Wells, Stratigraphic Tests, Core, or Other Exploratory Holes (Form 4) 

Wells 

Change in Depletion Plans Regulates drilling of additional 

wells 

Wyoming Oil & Gas Act (W.S. 30-5-110) 

Drilling and 

Drilling on State/Fee Minerals Regulates drilling of wells Wyoming Oil & Gas Act (W.S. 30-

5-110) 

Drilling and state/fee m

State Land Board Rights-of-way Grants Rights-of-way on State Lands W.S. 35-20 and 36-20 Roads and State Engineers Office Water Well Permit Grant Permit to drill water well and 

appropriate groundwater 

W.S. 41-121 through 147 Water Wel

LOCAL PERMITS, APPROVALS AND AUTHORIZING ACTIONS Sweetwater County, Wyoming Class II Permit Controls industrial development 

within the county 

Section 4.6 of the County Permit System 

All proposecomponen

Oil and Gas Location Permit Controls industrial development 

within the county 

County Permit System Wells 

County Road Crossing Permit Controls construction within 

county road rights-of-way 

 Pipelines 

Road Use Agreements and/or Oversize Trip Permit 

Oversize, overlength and overweight truck use of county roads 

Transportation of equipment and materials on county roads 
Appendix B 

Applicant-Committed Mitigation Measures 
Wind Dancer Natural Gas Development Proj. B-1 Applicant-Committed Mitigation Measures 

APPENDIX B: APPLICANT-COMMITTED MITIGATION 

MEASURES

Surface Use Plan 

Existing Roads: 

1. All existing roads to be used for this project shall be reconstructed and/or maintained 

consistent with BLM minimum standards as found in BLM Manual Section 9113. 

2. Existing roads shall be maintained in a condition as good as or better than the condition 

prior to the beginning of operations. The existing access road shall be regularly maintained 

in a safe and usable condition. A regular maintenance program may include, but is not 

limited to, blading, ditching, culvert installation, and gravel surfacing. 

3. All vehicles shall use only the authorized access road(s), as depicted in the approved APD. 

Vehicles shall not use any other access route to the drill/well pad and any ancillary facilities 

including, but not limited to, any two-track roads or trails and pipeline rights-of-way. 

4. If snow removal outside the new and existing roadways is undertaken, equipment used for 

snow removal operations shall be equipped with shoes to keep the blade at least six inches 

off the ground surface. Special precautions shall be taken where the surface of the ground is 

uneven to ensure that equipment blades do not destroy the vegetation. 

5. Unless otherwise exempted, free and unrestricted public access shall be maintained on the 

access road. 

Roads to be Constructed or Reconstructed: 

6. In the event production is established, the sub-base of the proposed road shall be thoroughly 

compacted (to at least 85% maximum dry density), and surfaced with at least four inches of 

gravel where road alignment-specific conditions require or as directed by the BLM. A 

temporary variance to this condition of approval may be granted if the Operator requests 

such a variance, in advance and in writing, during periods when soil moisture is low. 

7. Additional culverts (in addition to those specified in the APD) shall be placed along the 

proposed access road if the need arises, or as directed by the BLM Authorized Officer. The 

minimum diameter for culverts shall be 18 inches. All culverts shall have a minimum of 12 

inches fill or 1⁄2 the pipe diameter of fill, whichever is greater, placed on top of the culvert, 

and shall be of length sufficient to allow at least 24 inches of culvert to extend from the fill 

slope face (on both the inlet and outlet sides). The inlet & outlet shall be set at the gradient 

of the native ground or existing channel. If the culvert is being placed in an existing 

watercourse channel, the culvert shall be aligned with the existing channel. The entire 

length of pipe shall be bedded on native material before backfilling. Backfilling shall be 

completed using unfrozen material and rocks no larger than two inches in diameter. Care 
Wind Dancer Natural Gas Development Proj. B-2 Applicant-Committed Mitigation Measures 

shall be exercised to thoroughly compact the backfill around and under the culvert. Tamp 

each corrugation with a shovel handle. The backfill shall be brought up evenly in 6” lifts on 

both sides of the culvert and compacted. A permanent marker shall be installed at the inlet 

and outlet of the culvert to prevent vehicles from damaging the culvert. 

8. After the road is crowned and ditched, any berm located above the cutslope shall be 

removed, to allow overland flow to sheet across the cutslope into the ditch. 

9. Before proposed road construction activities begin, the topsoil (to a depth of at least 6 

inches) must be bladed to the side of the road and stockpiled to a depth of no greater than 24 

inches. The topsoil stockpile shall be contoured so as to prevent water ponding or flow 

concentration. Once the barrow ditch and the cut slopes are constructed, the topsoil shall be 

spread over the cut slopes. 

10. No construction or routine maintenance activities shall be performed during periods when 

the soil is too wet to adequately support equipment. If equipment (including licensed 

highway vehicles) creates ruts in excess of 4 inches deep, the soil shall be deemed too wet to 

adequately support construction equipment. 

11. Construction-related traffic shall be restricted to routes approved by the BLM Authorized 

Officer. New access roads or cross-country vehicle travel will not be permitted unless prior 

written approval is granted by the BLM Authorized Officer. 

12. Upon completion of the proposed access road(s), the roads shall be regularly maintained in a 

safe and usable condition. A regular maintenance program may include, but is not limited 

to, blading, ditching, culvert installation, and gravel surfacing. 

Existing and/or Proposed Facilities if Productive: 

13. The Operator shall comply with all federal, state, and local laws/regulations pertaining to 

disposal of produced water, including the use of properly permitted and authorized disposal 

sites.

14. All storage batteries and compressor facilities constructed or utilized as components of this 

project, including drain sumps and sludge holdings at compressor facilities, shall be 

surrounded by an impervious dike of sufficient size to hold the entire storage capacity of the 

largest tank in the facility and still allow one foot of freeboard or 110% of the capacity of 

the largest tank in the facility. The containment or diversionary structure shall be 

impervious to any oil, glycol, produced water, or other toxic fluid for 72 hours and would be 

constructed so that any discharge from a primary containment system would not drain, 

infiltrate, or otherwise escape to ground water, surface water, or navigable waters before 

cleanup is completed. 
Wind Dancer Natural Gas Development Proj. B-3 Applicant-Committed Mitigation Measures 

Location and Type of Water Supply: 

15. The water supply source for drilling must be approved and authorized by the State of 

Wyoming. 

Methods for Handling Waste Disposal: 

16. The Operator shall comply with the Hazardous Materials Management Summary provided 

in the Continental Divide/Wamsutter II EIS for hazardous materials that may potentially be 

used, produced, transported, disposed of, or stored on the well location. 

17. The Operator shall comply with all federal, state, and local laws and regulations pertaining 

to disposal of human and solid wastes. 

18. Fluids containing any hydrocarbons (condensate, diesel, etc.) shall not enter the reserve pit 

or production pit. 

19. Produced fluids shall be contained in test tanks during completion and testing. This fluid 

shall not be placed into the reserve pit without prior written approval from the BLM 

Authorized Officer. 

20. Within 90 days of initial production start-up, the Operator shall submit to the BLM 

Authorized Officer an analysis of the produced water. Produced water will be trucked offsite to an approved location not located on federal surface, or will be disposed of by other 

approve methods. Produced water pits will not be used. 

21. The reserve pit, if necessary, shall be lined with an impermeable liner. The impermeable 

liner shall have a permeability less than or equal to 1 X 10-7 cm/sec. The liner shall be 

installed so that the liner will not leak and shall be chemically compatible with all 

substances which may be placed into the pit. Liners made of any man-made synthetic 

material shall be of sufficient strength and thickness to withstand normal installation and pit 

use.

22. After evaporation and when dry, the reserve pit liners (if any) shall be cut off as near to the 

mud surface as possible and hauled to a legal landfill prior to backfilling the pit with a 

minimum of 5 feet of soil material. 

23. Fracturing fluids shall not be released into the flare pit. 

24. No fluids containing hydrocarbons or hazardous substances shall be allowed to accumulate 

in the flare pits. 

Well Site Layout: 

25. For the protection of livestock and wildlife, all pits and open cellars shall be fenced.

Fencing shall be in accordance with BLM specifications. Netting shall be placed over all 
Wind Dancer Natural Gas Development Proj. B-4 Applicant-Committed Mitigation Measures 

open production pits to eliminate any hazard to migratory birds or other wildlife. Netting is 

also required over reserve pits which have been identified as containing oil or hazardous 

substances (CERCLA Section 101(14)). The mesh diameter of netting shall be no larger 

than one inch. The reserve pit shall be fenced on three sides during drilling, and the working 

side shall be fenced immediately after the drilling rig is moved. Fencing shall meet BLM 

specifications. The reserve pit shall remain fenced until reclamation is initiated. 

26. At least 6 inches of topsoil shall be stripped from the well pad and stockpiled within the 

designated topsoil storage areas. 

27. If water is encountered within 50 feet of the surface, during construction of the rathole, 

reserve pit, or drilling of a water well, the Operator must contact the BLM Authorized 

Officer.

Surface Reclamation Plans: 

28. The following seed mixture shall be used. 

* These seed rates are for drill seeding, in pounds PLS (Pure Live Seed). If broadcast seeding, double the 

rates provided. 

29. Seeding shall be completed either late in the autumn (September 15 to November 15, before 

freeze up) after completion, or as early as possible the following spring to take advantage of 

available ground moisture. Seeding shall be repeated until a satisfactory stand is established 

as determined by the BLM Authorized Officer. If the seed is broadcast, twice the proposed 

drilled rate shall be used. 

30. After (1) recontouring all disturbed areas of the project to the original topography and (2) 

final grading and replacement of topsoil, the entire surface of the well site and access road 

shall be ripped to a depth of 18 to 24 inches on 18 to 24 inch centers. 

31. Rat and mouse holes (subgrade excavations for the conduct of drilling operations) shall be 

filled and compacted from the bottom to the top immediately upon release of the drilling rig 

from the location. 

Species Scientific Name Variety Pounds

PLS/Acre*

Grasses 

Slender wheatgrass Agropyron techycaulum 2.0 

Thickspike wheatgrass Agropyron dasystachyum Critana 4.0 

Western wheatgrass Agropyron smithii 2.0 

Indian ricegrass Oryzopsis hymenoides 1.0 

Bottlebrush squirreltail Sitanion hystrix 1.0 

Needle-and-thread Stipa comata 1.0 

Shrubs 

Gardner's saltbush Atriplex gardnerii 1.0 

Total 12.0 
Wind Dancer Natural Gas Development Proj. B-5 Applicant-Committed Mitigation Measures 

32. After the access road is completed, any of the original two-track roads and trails that remain 

shall be reclaimed by ripping to a depth of 18 to 24 inches at 18 to 24 inch spacing. 

33. All equipment, debris, and trash must be removed from the site prior to final reclamation 

operations.

34. Should the well become productive, all disturbed areas not needed for production operations 

shall be reclaimed (partial reclamation) as soon as possible, but no longer than within 2 

years from the date production facilities are completed. The production pad shall be as 

small as possible but no larger than one and a half acres. 

35. After the well is plugged and abandoned, the site shall be reclaimed as soon as possible, but 

no longer than within 2 years from the date of plugging. 

Pipeline Rights of Way (Pipe < 6 inches Inside Diameter)

36. Where pipelines cross ephemeral drainages, the Right-of-Way Holder(s) (Holder) shall 

ensure that the channel geometry after construction is nearly identical to that prior to 

construction, and that ephemeral flows will not be diverted or otherwise result in accelerated 

rates of erosion. 

37. The Holder is prohibited from discharging oil or other pollutants into or upon the navigable 

waters of the United States, adjoining shorelines, or the waters of the contiguous zone in 

violation of Section 311 of the Clean Water Act as amended, 33 U.S.C. 1321, and the 

regulations issued thereunder, or applicable laws of the State of Wyoming and regulations 

issued thereunder. Holder shall give immediate notice of any such discharge to the 

Authorized Officer and such other federal and state officials as are required by law to be 

given such notice. 

38. Prior to any discharge, hydrostatic testing water will be tested and processed, if necessary, to 

ensure that the water meets local, state or federal water quality standards. Prior to discharge 

of hydrostatic testing water from the pipeline, the Holder shall design and install a suitable 

energy dissipater at the outlets, and design and install suitable channel protection structures 

necessary to ensure that there will be no erosion or scouring of natural channels within the 

affected watershed as a result of such discharge. Sandbags, rock, or other materials or 

objects installed shall be removed from the site upon completion of hydrostatic testing. 

39. The Holder shall comply with all applicable Federal laws and regulations existing or 

hereafter enacted or promulgated. In any event, the Holder(s) shall comply with the Toxic 

Substances Control Act of 1976, as amended (15 U.S.C. 2601, et seq.) with regard to any 

toxic substances that are used, generated by or stored on the right-of-way or on facilities 

authorized under this right-of-way grant. (See 40 CFR, Part 702-799 and especially, 

provisions on polychlorinated biphenyls, 40 CFR 761.1-761.193.) Additionally, any release 

of toxic substances (leaks, spills, etc.) in excess of the reportable quantity established by 40 

CFR, Part 117 shall be reported as required by the Comprehensive Environmental Response, 
Wind Dancer Natural Gas Development Proj. B-6 Applicant-Committed Mitigation Measures 

Compensation and Liability Act of 1980, Section 102b. A copy of any report required or 

requested by any Federal agency or State government as a result of a reportable release or 

spill of any toxic substances shall be furnished to the authorized officer concurrent with the 

filing of the reports to the involved Federal agency or State government. 

Other:

40. The Operator shall have a qualified individual to serve as Compliance Coordinator available 

during active operations. This individual will be responsible for ensuring that all 

requirements of the Surface Use Plan and appropriate Conditions of Approval are applied. 

41. The construction of the well pad and all roads constructed or reconstructed on public lands 

shall be monitored by a licensed professional engineer or a qualified inspector (not the dirt 

contractor) to ensure that the construction of the well pad and road meets Bureau of Land 

Management standards as outlined in the approved APD. 

Resource Protection Measures 

Cultural and Paleontological Resources Protection:

42. A BLM-approved archaeologist will complete a Class III cultural resources field inventory 

over all surfaces where disturbance is proposed. Upon completion of the inventory, the 

BLM would review the reports generated by the archaeologist, and the BLM would ensure 

that the appropriate avoidance and mitigation measures were applied as COAs for the permit 

(whether for APD or ROW). 

43. The Operator shall be responsible for informing all personnel associated with this project 

that those persons shall be subject to prosecution for damaging, altering, excavating, or 

removing any archaeological, historical, or fossil objects or sites. If archaeological, 

historical, or fossil materials are discovered, the Operator shall immediately suspend all 

operations that may further disturb or damage such materials. The BLM Authorized Officer 

shall immediately be contacted and informed of the discovery of such materials. Operations 

shall not resume until written authorization to proceed is issued by the BLM Authorized 

Officer.

44. Within five working days, the BLM Authorized Officer will evaluate the discovery of such 

materials, and the Operator will be informed of the mitigations and/or actions necessary to 

prevent the loss of significant cultural or scientific values. 

45. The Operator shall be responsible for the cost of any mitigation required by the BLM 

Authorized Officer. The BLM Authorized Officer will provide technical and procedural 

guidelines for the conduct of mitigation. Upon verification from the BLM Authorized 

Officer that the required mitigation(s) have been completed, the Operator will be allowed to 

resume operations. 
Wind Dancer Natural Gas Development Proj. B-7 Applicant-Committed Mitigation Measures 

Recreational and Visual Resources Protection: 

46. All above-ground structures, production equipment, tanks, transformers, and insulators not 

subject to coloring requirements for safety shall be painted the color of “Carlsbad Canyon” 

(2.5Y 6/2). Further detail on the coloring requirements may be obtained from the BLM 

Authorized Officer, if necessary. 

Soil and Plant Community Resources Protection: 

47. The Operator shall be responsible for the total control of all invasive/noxious weed species 

on any and all disturbed sites associated with this APD, including, but not limited to, the 

drill/well pad, access road(s), and pipeline rights-of-way. The Operator is responsible for 

consulting with the BLM Authorized Officer and, if necessary, local authorities prior to 

control activities of weed-infested areas. The Operator shall notify the Authorized Officer if 

invasive and/or noxious weeds are observed within the disturbed areas associated with this 

APD. The Operator shall obtain written approval from the BLM Authorized Officer prior to 

initiating weed control operations. 

48. The Operator or contractor will obtain proper BLM pesticide application permits and would 

comply with the applicable federal and state laws and regulations concerning the use of 

pesticides (e.g., insecticides, herbicides, fungicides, rodenticides, and other similar 

substances) in all activities/operations under this permit. Pesticides will not be permanently 

stored on public lands. 

Wildlife Resource Protection: 

49. If a raptor tries to nest on or in any well buildings or facilities, the Operator shall 

immediately notify the BLM Authorized Officer. 

50. Within one mile of active ferruginous hawk and eagle nests, and within 3⁄4-mile of all other 

active raptor nests, construction, drilling and other activities potentially disruptive to nesting 

raptors are prohibited during the period of February 1 to July 31. 

51. Within two miles of identified sage grouse leks, construction, drilling and other activities 

potentially disruptive to strutting and nesting sage/sharp-tailed grouse are prohibited during 

the period of March 1 to June 30. 

52. All surface-disturbing activities shall be restricted from encroaching to within 1⁄4-mile of 

identified sage grouse leks. 

53. When located in occupied mountain plover habitat, construction, drilling, reclamation and 

other activities are prohibited during the reproductive period of April 10 to July 10. Should 

construction, drilling and other activities be anticipated between these dates, an exception 

must be granted by the BLM Authorized Officer, and consistent with the March 2002 

USFWS Mountain Plover Survey Guidelines. 
Wind Dancer Natural Gas Development Proj. B-8 Applicant-Committed Mitigation Measures 

54. If it were determined there is any activity in the area by endangered species not previously 

discovered, the BLM and Operator will confer and any necessary and appropriate steps 

would be taken. 

Miscellaneous Permitting Requirements 

55. All survey monuments found within the area of operations shall be protected. Survey 

monuments include, but are not limited to, (1) General Land Office and Bureau of Land 

Management Cadastral Survey Corners, reference corners, witness points, U.S. Coast and 

Geodetic Survey benchmarks and triangulation stations, military control monuments, and 

recognizable civil (both public and private) survey monuments. In the event of obliteration 

or disturbance of any survey monuments, the incident shall be reported in writing to the 

BLM Authorized Officer. 

56. The Operator shall be held responsible for the prevention and suppression of fires on public 

lands caused by its employees, contractors, or subcontractors. During conditions of extreme 

fire danger, surface use operations may be either limited or suspended, or additional 

measures may be required by the BLM Authorized Officer. The occurrence of any wildland 

fire shall be reported immediately to the BLM Fire Dispatch, 1 (800) 295-9953. 

57. No flaring of gas shall be allowed into the reserve pit without prior approval by the BLM 

Authorized Officer. 

58. The Operator shall comply with all Federal, State, and local laws, rules, and regulations, 

including the acquisition of any necessary Federal, State, and/or local permits. 

59. The Operator will construct, operate, and maintain the facilities and structures within the 

grants and/or permits in conformance with the descriptive and technical data which were 

furnished the BLM in connection with the application for these grants and/or permits. Any 

relocation, additional construction, or use which is not in accord with such data may not be 

initiated without prior written approval of the Authorized Officer. 

60. Monitoring of construction, drilling, and rehabilitation operations will be provided by the 

Operator. A BLM compliance officer may make regular inspections of all activities during 

construction, drilling, and follow-up restoration/reclamation. 

61. Discharges, spills, fires, accidents, or blowouts will be reported to the Authorized Officer in 

accordance with “Notice to Lessee-Reporting of Undesirable Events” (NTL-3A), or an 

applicable Onshore Oil and Gas Order. Containment of hydrocarbons and procedures for 

handling the above is contained in the Operator’s Spill Prevention Control and 

Countermeasure Plan (SPCC) as required under 40 CFR, Part 112. 

62. Operator will assist in the prevention of illegal discharge of firearms whenever possible. 

This measure would help reduce vandalism and wildlife violation incidents.