DRAFT

ENVIRONMENTAL IMPACT STATEMENT

Seminoe Road Gas Development Project

Carbon County, Wyoming

U.S. Department of the Interior

Bureau of Land Management

Wyoming State Office

Rawlins Field Office

NOVEMBER 2005 


FACT SHEET 

Project Title: Seminoe Road Gas Development Project 

Document: Draft Environmental Impact Statement 

Issue Date: November 2005 

Project Location: Carbon County, Wyoming 

Proponent: Dudley & Associates, LLC 

1776 Lincoln Street, Room 904 

Denver, Colorado 80203 

Preparing Agency: U.S. Department of the Interior 

Bureau of Land Management 

Rawlins Field Office 

1300 North 3rd Street 

Rawlins, Wyoming 82301-2407 

Responsible Official: Bob Bennett, BLM Wyoming State Director 

Contact Person: David Simons, BLM EIS Coordinator 

Abstract: The Seminoe Road Project draft EIS describes the physical, biological, social and 

economic resources that would be potentially affected by the development of the Seminoe Road 

Project. The BLM is the lead agency in the preparation of this EIS and must decide which 

alternatives to select for the project. This project is a proposed natural gas development and 

operation planned for an area 20 miles northeast of Rawlins, Wyoming. The Seminoe Road 

Project would involve the drilling and developing of up to 1,240 wells, on up to 785 well pad sites 

spaced at one well pad site every 160 acres. Associated facilities would include roads, gas and 

water collection pipelines, compressor stations, water disposal systems, and an electric power 

supply system. The project area encompasses 137,000 acres. Total disturbance for drill pads, 

access roads and associated facilities would be an estimated 6,174 acres (4.5% of the project 

area). Construction and drilling activities are planned to occur over a 10-year period from the start 

of the project. Approximately 60% of the initial site disturbance would be reclaimed after 

construction; therefore, an estimated 2,349 acres (1.7% of the project area) would remain 

disturbed for long-term operations; this area would be reclaimed at the conclusion of the estimated 

30-year project life. 

Comment Period: The comment period on this draft EIS will be 60 days from the date the 

Environmental Protection Agency publishes the Notice of Availability in the Federal Register. 

Comments to the Seminoe Road EIS Project draft EIS should be sent to the BLM Rawlins 

Field Office, P.O. Box 2407, Rawlins, Wyoming 82301-2407, faxed to (307) 328-4224 or emailed to rawlins_wymail@blm.gov, Attention David Simons. 

Important Notice: 

Reviewers must provide the BLM with their comments during the review period of the draft EIS. 

This will enable the BLM to analyze and respond to the comments at one time and to use 

information acquired in the preparation of a final EIS. Comments on the draft EIS should be 

specific and should address the adequacy of the statement, as well as the merits of the 

alternatives discussed (40 CFR 1503.3). 
EXECUTIVE SUMMARY
November 2005 Draft Environmental Impact Statement

Executive Summary

I. INTRODUCTION 

The Bureau of Land Management (BLM) is analyzing a proposed coalbed natural gas 

development and operation known as the Seminoe Road Gas Development (Seminoe Road) 

Project. Dudley and Associates, LLC is the project proponent. 

This Seminoe Road Project is located in an area approximately 20 miles northeast of Rawlins, in 

Carbon County, Wyoming. The project contemplates the drilling and development of up to 1,240 

wells, on up to 785 well pad sites, which would be spaced at one well pad site every 160 acres. 

Associated facilities would include access roads, gas and water collection pipelines, compressor 

stations, water disposal systems, and an electric power supply system. 

In September 2002, the BLM determined that the requirements of the National Environmental 

Policy Act (NEPA) would be best served by preparing an environmental impact statement (EIS) 

for the project. 

This EIS encompasses a 137,000-acre analysis area, which involves a checkerboard pattern of 

mostly federal (greater than 49%) and private (greater than 49%) surface, with some state lands 

(less than 1%). The purpose of examining this large area is to provide BLM resource managers 

with a broad overview of the full development potential for coalbed natural gas resources in this 

part of Wyoming and to obtain a general understanding of the effects and impacts that might 

occur with such a development. The BLM decided that a comprehensive analysis of the entire 

potential development serves the interests of the BLM, the Proponent and the general public 

versus piecemeal analysis of commercial development “add-ons” to the Proponent’s existing Pilot 

Project. 

In practical terms, both the BLM and Proponent recognize that prudent management dictates that 

a project of this size would be best engineered, analyzed, and developed in a series of phases. As 

a result, the Proponent plans for approximately ten distinct development phases across the EIS 

analysis area. Each phase would be individually and independently reviewed by the BLM with 

subsequent site-specific environmental reviews that conform with NEPA regulations and 

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Draft Environmental Impact Statement November 2005

guidelines. Experience and knowledge gained from each phase would be applied to better plan 

and implement each subsequent phase. 

Each phase would involve the drilling of an average of 124 wells, with associated road 

construction and installation (burial) of water, gas and electrical distribution lines. The Proponent 

would submit plans to the BLM for each phase, and the BLM would conduct appropriate NEPA 

analysis for each phase before making a final decision. This EIS would serve as an “over-arching” 

tool to assist the BLM in making better decisions regarding individual projects phases. 

The BLM (Rawlins Field Office) is the lead agency in the preparation of this EIS. As required by 

NEPA, the BLM announced their intent to prepare an EIS for the Seminoe Road Project in the 

Federal Register on March 13, 2003. A 60-day EIS scoping process was initiated to solicit 

comments from the general public, businesses, special interest groups, Native American tribes, 

and government agencies regarding the project. Public scoping meetings were held on May 7, 

2003, at the Town Hall in Hanna, Wyoming, and on May 8, 2003, at the BLM Rawlins Field Office 

in Rawlins, Wyoming. Eighteen letters were received during the EIS scoping process, which 

ended on May 14, 2003. 

A. Background 

During the summer of 2001, the Proponent completed construction of the Seminoe Road Coalbed 

Methane Pilot Project (Pilot Project) to determine the commercial feasibility of producing gas from 

coal formations in this area. Sixteen pilot production wells and one pressure observation well were 

installed. Many of these wells have begun to produce small amounts of gas; however, the Pilot 

Project production results are still being analyzed. 

The BLM previously prepared an environmental assessment (EA) for the Pilot Project (WY-030­

EA00-288). In addition, the BLM prepared a separate EA (WY-030-EA2-229) for the installation of 

a compressor facility and a 20-mile long, high-pressure pipeline from the Pilot Project to a 

commercial interconnect near Walcott, Wyoming. The BLM approved their construction in 2002; 

installation of the compressor and high-pressure pipeline is pending further Pilot Project results. 

B. Purpose and Need 

With the preparation of this EIS, the BLM is responding to the proposed project plans submitted 

by the Proponent for full field development. The Proponent’s purpose for the Seminoe Road 

Project is the economical recovery and sale of natural gas resources to US markets. As America's 

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November 2005 Draft Environmental Impact Statement

need for energy continues, natural gas has emerged as an important industrial and domestic fuel 

source. The development of domestic gas reserves reduces the country's dependence on foreign 

sources of energy and maintains a supply of fuel for domestic consumption, industrial production, 

power generation and national security. Natural gas development has also historically been, and 

continues to be, an important and integral part of the state and local economies in Wyoming. 

C. Phased Approach 

This EIS analyzes full field development to be implemented in phases. The Proponent plans for a 

minimum of ten distinct development phases across the EIS analysis area, and each phase would 

be individually and independently reviewed by the BLM, with subsequent site-specific 

environmental reviews that conform to NEPA regulations and guidelines. Experience and 

knowledge gained from each phase would be applied to better plan and implement the next 

subsequent phase. 

Each phase would involve the drilling of an average of 124 wells, with associated road 

construction and installation (burial) of water, gas, and electrical distribution lines. The Proponent 

would submit plans to the BLM for each phase, and the BLM would conduct appropriate 

environmental analyses for each phase before making a final decision. 

D. Issues and Concerns 

The 2003 scoping process helped the BLM focus on key issues and concerns important to the 

public and various governmental agencies in preparation of a full field EIS. The issues and 

concerns addressed in the Seminoe Road EIS are as follows: 

� Air Quality: Identify and mitigate project-related air quality impacts. 

� Cultural Resources: Identify cultural resources, minimize disturbance impact to these 

resources, and conduct Native American consultation. 

� Hydrology (Surface and Ground Water): Identify and mitigate surface and ground 

water impacts to ensure watersheds are protected and maintained. 

� Land Use: Minimize land disturbances and consider issues arising from area surface 

and mineral ownership differences. 

� Noise: Identify and mitigate noise impacts. 

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Draft Environmental Impact Statement November 2005

� Weeds: Prevent the introduction and spread of weeds in the project area. 

� Health and Safety: Protect public and worker health and safety. 

� Recreation: Mitigate impacts on recreational activities. 

� Roads/Transportation: Address construction and operational traffic impacts. 

� Socioeconomics: Address the social and economic impacts on local residents. 

� Soils: Identify and minimize project-related soil impacts. 

� Vegetation: Address project-related impacts to vegetation and wetlands. 

� Visual Resources: Mitigate project-related impacts on protected view sheds. 

� Wildlife: Mitigate impacts on wildlife and wildlife habitat. 

E. Decisions to be Made 

Following the close of the 60-day draft EIS review and comment period, the BLM will consider 

comments submitted by the public, interested organizations and government agencies, and the 

BLM will respond to substantive comments in a final EIS. In accordance with 40 CFR 1503.4, the 

BLM may decide to modify alternatives, develop new alternatives, modify the draft EIS analysis, 

make revisions in the final EIS, and/or explain why comments do or do not warrant further 

response. 

After the release of the final EIS, the BLM will issue a Record of Decision (ROD) regarding its 

respective decision on the proposed action or selected alternative. In the ROD, the BLM 

responsible official may decide to adopt the no action alternative, adopt the proposed action (with 

or without additional mitigation monitoring measures), adopt an alternative with features of several 

of the alternatives, or adopt one of the action alternatives with additional mitigation and monitoring 

measures. 

II. ALTERNATIVES INCLUDING PROPOSED ACTION 

The discussion of alternatives is the foundation of the EIS process. Alternatives are developed 

and analyzed for an EIS to respond to the purpose for and need of the proposed action, to 

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November 2005 Draft Environmental Impact Statement

address social and environmental issues, to respond to public and agency input, and to satisfy 

NEPA regulations. 

The BLM explored and evaluated numerous ideas and options during the selection and 

development of action alternatives for this draft EIS. In total, four alternatives, which include the 

no action and proposed action alternatives, are evaluated. 

A. Alternative A – No Action 

NEPA regulations [40 CFR 1502.14(d)] require that EIS alternative analysis include the alternative 

of no action. However, in reality, BLM authority to implement a no-action alternative that totally 

denies an oil and gas project is limited because issued oil and gas leases already grant the lessee 

the “exclusive right and privilege to drill for, mine, extract, remove and dispose of oil and gas 

deposits.” In checkerboard ownership, where the surface and mineral rights of every other 

section have private (non-federal government) control, a project proponent could pursue 

development and drilling on those private lands, if BLM delayed or denies approval of drilling on 

federal sections. 

For purposes of this EIS, the no action alternative assumes that the proposal as submitted by the 

Proponent is denied. Previously authorized operations including those approved by the Seminoe 

Pilot Project EA would be developed, and gas would be transported in the manner described in 

the EA and Decision Record prepared for the distribution pipeline. 

B. Alternative B – Proposed Action 

Alternative B presents the actions proposed by the Proponent for the development, operation and 

reclamation of this gas extraction project. 

The Proponent proposes to drill up to 1,240 natural gas wells on up to 785 well pad locations, 

which would be spaced at approximately one well pad site every 160 acres. The life of the project 

is anticipated to be 30 years. Following BLM’s satisfaction of its NEPA requirement and other 

regulatory approval, the Proponent desires to initiate field development in late 2005 or early 2006. 

Disturbance projections for the project are set forth in Table ES-1, Preliminary Estimate of 

Surface Area Disturbance. 

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Draft Environmental Impact Statement November 2005

Table ES-1, Preliminary Estimate of Surface Area Disturbance 

Facility 

Initial Disturbance Area2 

(acres) 

Operational Disturbance Area3 

(acres) 

Drill Pads 4 1,727 785 

Access Roads5 2,854 1,427 

Utilities6 1,427 0 

Water Discharge Facilities7 79 79 

Erosion Management Facilities8 57 28 

Compressor Facilities9 30 30 

Total Disturbed Area 6,174 2,349 

Percentage Disturbance of Total Project Area10 4.5% 1.7% 

Notes: 

1. This table presents the total area estimated to be disturbed within the Seminoe Road Project during the 

projected 30-year life of the project. 

2. The initial disturbance represents the area disturbed as a result of drill pad construction, access roads, gas, 

water and utility rights-of-way, compressor stations, and treated water-handling systems. 

3. Part of the area initially disturbed by drilling operations would be reclaimed (~55%) shortly after each well is 

completed and equipped. The area not reclaimed would be used for ongoing operations. Once the gas 

resource is depleted, facilities would be removed and the balance of the drill pad would then be reclaimed. 

4. An estimated 785 drill pads would be created in the project area. The area needed for drilling operations 

would average about 2.2 acres for each well pad location. Subsequent reclamation would reduce the drill 

pad size to approximately 1 acre, the area needed for production operations. 

5. Each drill pad would require an estimated average 0.6 miles of access road for which an estimated width of 

50 feet will be physically affected by the construction process. Fifty percent of the area initially disturbed by 

road construction (25’) would be reclaimed following construction activities. Access roads would remain in 

service for the life of the project. 

6. “Utilities” include gas and water collection pipelines, power lines and their ancillary facilities, and 

communications lines. Utilities corridors are ordinarily laid out parallel to and installed simultaneously with 

the access roads, initially utilizing an average width of 25 feet and an estimated average 0.6 miles length for 

each drill pad. Once utilities are installed and buried, the disturbed areas would be fully reclaimed. 

7. The measured surface disturbance at the Pilot Project for DS-1, DS-2 and DS-3 water treatment facilities is 

1.26 acres serving sixteen wells. Experience indicates that the construction, installation, and operation of 

water discharge facilities would entail an average disturbance of 0.1 acre allocated to each drill pad. These 

facilities would remain in service for the life of the project. 

8. The Proponent did not include erosion control and management for ephemeral drainages below produced 

water discharge points as part of its proposed action. Given potential erosion concerns in the ephemeral 

drainages down-drainage of where produced water would be released, the BLM is considering possible 

mitigation that would include erosion control management facilities and structures, such as Gabions, 

concrete weirs, sheet piling, grade control, or other similar structures, as necessary to minimize erosion in 

ephemeral drainages resulting from produced water. To inform agency decision makers and the public, the 

BLM has made an estimate of the possible acreage that might be disturbed as a result of the installation of 

such erosion control management structures. See Appendix O, Erosion Management for Ephemeral 

Drainages. 

9. It is also presumed that three compressor stations would be required to adequately serve the project, each 

requiring an estimated 10 acres, for a total projected disturbance of 30 acres. 

10. This percentage is based on an estimated 137,000 acres within the EIS analysis area. 

Natural gas would be produced in separate well bores from two distinct Cretaceous coal 

formations (the Mesaverde and Medicine Bow/Fox Hills formations); these targeted zones are 

separated by several thousand feet of low permeability sand and shale. Productive windows of 

gas extraction range from depths of 500 to 14,000 feet for the Mesaverde coals, with projected 

production depths of 500 to 10,000 feet for the overlying Medicine Bow/Fox Hills coals. The 

apparent duplication of producing horizons is due to the locally steep dip of the Cretaceous 

formations, which plunge east into the Hanna Basin at 10 to 15 degrees within the EIS analysis 

area. 

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November 2005 Draft Environmental Impact Statement

Natural gas would be produced in separate well bores from two distinct Cretaceous coal 

formations (the Mesaverde and Medicine Bow/Fox Hills formations); these targeted zones are 

separated by several thousand feet of low permeability sand and shale. Productive windows of 

gas extraction range from depths of 500 to 14,000 feet for the Mesaverde coals, with projected 

production depths of 500 to 10,000 feet for the overlying Medicine Bow/Fox Hills coals. The 

apparent duplication of producing horizons is due to the locally steep dip of the Cretaceous 

formations, which plunge east into the Hanna Basin at 10 to 15 degrees within the EIS analysis 

area. 

Produced natural gas from wells would be transported to one of three centralized compressor 

stations via an underground pipeline gathering system. From the compressors, natural gas would 

be transported in a buried, high-pressure gathering pipeline to a commercial interconnect near 

Walcott, Wyoming. Water gathering lines would be installed in the same trench as the gas 

gathering pipelines; water would be delivered to appropriate treatment and discharge systems. 

An estimated 29 to 44 gallons of water per minute (gpm) would be pumped from each well via a 

submersible pump. This expected water production range would remain constant for each well for 

at least a year, and thereafter is expected to decline at 10 to 15% annually. This produced water 

would be discharged to intermittent and ephemeral drainages and playa areas at various locations 

within the EIS analysis area. 

The plan proposes that the Seminoe Road Project would be completely electrified; however, the 

Proponent may temporarily use propane, natural gas-fired or diesel engines or generators at 

individual well sites. Electric distribution lines would be buried in trenches, alongside access 

roads, separate from the infield gas and water lines. Electricity for the Seminoe Road Project 

would likely come from the existing Western Area Power Authority (WAPA) 115kV transmission 

line that crosses the EIS analysis area. An approximate 8,000 foot-long overhead transmission 

line extension would be constructed from the WAPA line to a substation, from which electric 

distribution lines would feed the compressors and well pad sites. 

During the 10 years of expected construction and well development, an estimated workforce of 80 

to 110 people would be employed. A range of approximately 40 to 60 employees and contractors 

would be needed for normal day-to-day operations. Decommissioning and final reclamation 

activities at the end the project life would require approximately 30 to 50 people. 

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Draft Environmental Impact Statement November 2005

Both interim and final reclamation would be implemented for the project. The purpose of 

reclamation is to return disturbed areas to stabilized and productive conditions that ensure longterm protection of land and water resources. The post-project land uses would be managed for 

grazing, wildlife habitat and dispersed recreation. 

C. Alternative C – Direct Discharge 

Alternative C would be similar to Alternative B with two exceptions. First, unlike Alternative B, 

where produced water is discharged to intermittent/ephemeral drainages and playa areas, 

produced water from the water collection and treatment facilities would be routed to and 

discharged directly into the North Platte River or Seminoe Reservoir. Second, as a comparison to 

the electrified scenario presented for Alternative B, natural gas powered compressors and downhole well pumps would be utilized for Alternative C. 

Although there are a number of possible design and engineering options for routing produced 

water for direct discharge into Seminoe Reservoir or the North Platte River, including buried 

pipelines, surface pipelines, open ditches or canals, Alternative C contemplates using buried 

pipelines that would parallel drainages. 

Because produced water has a relatively warm temperature (90 to 95°F), ponds would be used to 

“cool” produced water to a temperature consistent with the receiving water. These ponds would 

have capacity of storing several days of produced water, and each pond would be designed and 

constructed with a principal and emergency spillway. The principal spillway would allow for 

discharge of produced water into the buried pipeline that would conduct water for direct discharge 

into Seminoe Reservoir or the North Platte River. 

An estimated 16 ponds would be required. Assuming 2 to 3 acres of disturbance for pond 

construction and water impoundment, approximately 32 to 48 acres would be affected with the 

installation of these ponds. An estimated 17 miles of buried water pipeline would also be installed 

and buried in a trench at depths of 4 to 6 feet. Assuming a 50-foot wide disturbance corridor for 

this pipeline installation, an estimated additional 103 acres would be disturbed for pipeline 

installation. The BLM expects that this disturbance would be reclaimed within a year of installation. 

D. Alternative D – Underground Injection 

Under Alternative D, produced water would be injected into the Dad Sandstone, a 30 to 40 feet 

thick sandstone layer found within the 1,000-foot thick Lewis Shale Formation that separates the 

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November 2005 Draft Environmental Impact Statement

Medicine Bow/Fox Hills and Mesaverde coals. Within the EIS project area, a series of water 

injection facilities would be installed at strategic locations and produced water would be piped 

there. 

Injection facilities would require electric-powered water-injection pumping equipment and 

associated infrastructure (water holding tanks, water storage ponds, enclosed structures for 

pumps and operational controls, pumps, and storage room for piping, valves and other spare 

parts. Similar to Alternative C, several days of reserve water capacity (tanks or water holding 

ponds) would be necessary adjacent to water injection facilities to allow time for routine or 

emergency maintenance on water injection facilities. 

Two or more injection wells would be needed at each point of injection to allow for efficient and 

continuous injection. Experience at the existing coalbed natural gas activities at the Atlantic Rim 

Project, located southwest of Rawlins, Wyoming, indicates that one injection well is needed for 

every 8 to 12 gas wells. At this ratio, the Seminoe Road Project would require approximately 100 

to 150 water injection wells, distributed throughout the EIS analysis area. 

The other aspects of Alternative D would remain the same as for Alternative B. 

III. ALTERNATIVES CONSIDERED BUT ELIMINATED FROM DETAILED 

EVALUATION 

A number of alternatives were considered but eliminated from detailed study in the EIS. Based on 

technical environmental, legal and regulatory constraints, the alternatives considered but 

eliminated include: 

� Mandated directional or horizontal drilling; 

� Tighter well pad spacing; 

� On-site centralized power; 

� Individual well site power generation; 

� Alternative energy sources, such as wind or solar power; 

� Overhead electric distribution lines; 

Seminoe Road Gas Development Project ES­9
Draft Environmental Impact Statement November 2005

� Alternative water handling systems, including irrigation, evaporation, piping to local 

municipalities and/or industries, and misting towers; 

� Alternative water treatment methods, including ion exchange, reverse osmosis, 

nanofiltration, and electrodialysis; and, 

� Sole use of existing roads. 

ES­10  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Table of Contents

Chapter 1 – Purpose of and Need for Action

1.1 Introduction.....................................................................................................1­1

1.2 Background ......................................................................................................1­1

1.3 Purpose and Need ...........................................................................................1­2

1.4 EIS Scoping Process .........................................................................................1­2

1.5 Issues and Concerns ........................................................................................1­3

1.5.1 Air Quality ......................................................................................................1­3

1.5.2 Cultural Resources........................................................................................1­3

1.5.3 Hydrology (Surface and Ground Water)....................................................1­3

1.5.4 Land Use.........................................................................................................1­4

1.5.5 Noise...............................................................................................................1­4

1.5.6 Weeds.............................................................................................................1­4

1.5.7 Public and Worker Health and Safety .......................................................1­4

1.5.8 Recreation .....................................................................................................1­4

1.5.9 Roads/Transportation ..................................................................................1­4

1.5.10 Socioeconomics............................................................................................1­5

1.5.11 Soils.................................................................................................................1­5

1.5.12 Vegetation.....................................................................................................1­5

1.5.13 Visual Resources............................................................................................1­5

1.5.14 Wildlife...........................................................................................................1­5

1.6 Critical Elements Not Considered in Detail...................................................1­6

1.7 Decisions to be Made ......................................................................................1­6

1.8 Agency Responsibilities and Jurisdictions....................................................1­7

1.9 Conformance With BLM Land Use Plans........................................................1­7

1.10 Additional NEPA Analysis ................................................................................1­8

1.11 Regional Activity..............................................................................................1­8

Chapter 2 – Alternatives Including the Proposed Action

2.1 Introduction.....................................................................................................2­1

2.2 No Action Alternative (Alternative A)............................................................2­1

2.3 Formulation of Action Alternatives ..............................................................2­1

2.4 Alternative B – Proposed Action ...................................................................2­2

2.4.1 Planning and Pre­Construction Activities.................................................2­4

2.4.2 Roads..............................................................................................................2­4

2.4.3 Well Pads........................................................................................................2­6

2.4.4 Drilling and Production Operations ..........................................................2­6

2.4.5 Gas and Water Gathering Systems .............................................................2­7

2.4.6 Compressor Stations....................................................................................2­7

2.4.7 Gas Gathering Pipeline and Terminal Facilities ........................................2­8

2.4.8 Produced Water Management...................................................................2­8

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Draft Environmental Impact Statement November 2005

2.4.9 Beneficial Use of Produced Water...........................................................2­10

2.4.10 Power ...........................................................................................................2­11

2.4.11 Work Force ..................................................................................................2­12

2.5 Direct Discharge of Produced Water Into Seminoe Reservoir and

North Platte River (Alternative C) ................................................................2­12

2.6 Underground Injection of Produced Water (Alternative D).....................2­14

2.7 Reclamation Measures ..................................................................................2­16

2.8 Management, Mitigation and Monitoring Measures .................................2­16

2.8.1 Planning and Design ..................................................................................2­17

2.8.2 Sewage, Trash and Other Waste Material................................................2­17

2.8.3 Cultural and Historic Resources................................................................2­18

2.8.4 Paleontological Resources ........................................................................2­18

2.8.5 Vegetation...................................................................................................2­18

2.8.6 Weeds...........................................................................................................2­19

2.8.7 Road Construction/Transportation..........................................................2­19

2.8.8 Chemicals and Hazardous Materials.........................................................2­21

2.8.9 Air Quality ....................................................................................................2­22

2.8.10 Topography and Phisiography.................................................................2­22

2.8.11 Soils and Erosion Control ..........................................................................2­22

2.8.12 Water Resources.........................................................................................2­23

2.8.13 Wetlands, Special Aquatic Sites, and Waters of the U.S........................2­24

2.8.14 Noise and Odor ...........................................................................................2­25

2.8.15 Wildlife and Fisheries.................................................................................2­25

2.8.16 Threatened, Endangered, Proposed, Candidate and Sensitive

Species .........................................................................................................2­26

2.8.17 Livestock/Grazing Management ...............................................................2­27

2.8.18 Socioeconomics..........................................................................................2­27

2.8.19 Land Use.......................................................................................................2­27

2.8.20 Recreation ...................................................................................................2­27

2.8.21 Visual Resources..........................................................................................2­27

2.8.22 Health and Safety.......................................................................................2­28

2.9 Environmental Monitoring Measures..........................................................2­28

2.9.1 Air Quality ....................................................................................................2­29

2.9.2 Water Resource Monitoring .....................................................................2­29

2.9.3 Wildlife Monitoring....................................................................................2­30

2.9.4 Reclamation Monitoring ...........................................................................2­30

2.9.5 Weed Monitoring .......................................................................................2­30

2.9.6 Reporting to Regulatory Authorities ......................................................2­30

2.10 Alternatives Considered but Eliminated From Detailed Evaluation .......2­30

2.10.1 Mandated Directional or Horizontal Drilling..........................................2­31

2.10.2 Tighter Well Pad Spacing...........................................................................2­31

2.10.3 On­site Centralized Power.........................................................................2­32

2.10.4 Individual Well Site Power Generation....................................................2­33

2.10.5 Alternative Energy Sources ......................................................................2­33

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November 2005 Draft Environmental Impact Statement

2.10.6 Overhead Electric Distribution Lines.......................................................2­34

2.10.7 Alternative Water Handling Systems.......................................................2­35

2.10.7.1 Irrigation ............................................................................................2­35

2.10.7.2 Evaporation and/or Percolation Ponds .........................................2­36

2.10.7.3 Piping Water to Municipalities and/or Industries.........................2­36

2.10.7.4 Misting Towers ..................................................................................2­37

2.10.8 Alternative Water Treatment Methods ..................................................2­38

2.10.9 Sole Use of Existing Roads.........................................................................2­38

2.11 Comparison of Alternatives .........................................................................2­39

Chapter 3 – Affected Environment

3.1 Air Quality/Climate...........................................................................................3­1

3.1.1 Regional Climate...........................................................................................3­1

3.1.2 Ambient Air Quality Standards...................................................................3­3

3.1.3 Regional Air Quality......................................................................................3­3

3.1.4 Air Permitting Requirements for Industrial Sources ..............................3­6

3.2 Soils ...................................................................................................................3.7

3.2.1 General Soil Characteristics.........................................................................3­8

3.2.2 Saline/Sodic Soils...........................................................................................3­8

3.2.3 Shallow Soils ..................................................................................................3­9

3.2.4 Soils Overlying Steep (>25 Percent) Slopes............................................3­10

3.2.5 Highly Erodible Soils ..................................................................................3­10

3.2.6 Areas of Sensitive Soil Concentrations....................................................3­11

3.2.7 Cryptobiotic Soils .......................................................................................3­11

3.3 Geology...........................................................................................................3­11

3.3.1 General Geology .........................................................................................3­12

3.3.2 Geologic Hazards ........................................................................................3­12

3.3.3 Paleontology...............................................................................................3­13

3.4 Surface Water.................................................................................................3­13

3.4.1 Hydrologic Setting.....................................................................................3­13

3.4.2 North Platte River.......................................................................................3­14

3.4.2.1 General Overview of the North Platte Drainage System ...............3­15

3.4.2.2 North Platte River Upstream of Seminoe Reservoir.......................3­17

3.4.2.3 Seminoe Reservoir ...............................................................................3­17

3.4.2.4 Kortes Reservoir ...................................................................................3­19

3.4.2.5 Miracle Mile ...........................................................................................3­19

3.4.2.6 Pathfinder Reservoir ...........................................................................3­20

3.4.2.7 North Platte River Downstream of Pathfinder Reservoir..............3­20

3.4.3 Medicien Bow River....................................................................................3­21

3.4.4 Intermittent Drainages Within the EIS Analysis Area............................3­21

3.4.4.1 O’Brien Creek ........................................................................................3­21

3.4.5 Ephemeral Drainages Within the EIS Analysis Area ...............................3­22

3.4.5.1 Pool Table Draw....................................................................................3­24

3.4.5.2 Ayers Draw ............................................................................................3­26

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Draft Environmental Impact Statement November 2005

3.4.5.3 Dirtyman Draw......................................................................................3­27

3.4.5.4 Dry Ditch................................................................................................3­27

3.4.5.5 Unnamed Drainage #1.........................................................................3­28

3.4.5.6 Longhart Draw......................................................................................3­28

3.4.5.7 Unnamed Drainage #2.........................................................................3­28

3.4.5.8 St. Mary’s Ditch .....................................................................................3­28

3.4.5.9 Mountain Lion Draw.............................................................................3­29

3.4.5.10 Unnamed Drainage #3.........................................................................3­29

3.4.6 Playas Within the EIS Analysis Area..........................................................3­29

3.4.6.1 Ferris Lake .............................................................................................3­30

3.4.6.2 Alkali Flats..............................................................................................3­30

3.4.6.3 St. Mary’s Anticline Basin.....................................................................3­30

3.5 Ground Water.................................................................................................3­30

3.5.1 Hanna Basin.................................................................................................3­30

3.5.2 Hanna Basin Bedrock Ground Water Systems in the EIS Analysis

Area ..............................................................................................................3­31

3.5.2.1 Mesaverde Group (Deep ground water bearing formations) .......3­31

3.5.2.2 Lewis Shale ............................................................................................3­32

3.5.2.3 Fox Hills Sandstone/Medicine Bow Formation (Shallow Ground

Water Bearing Formations) ................................................................3­33

3.5.3 Hanna Basin Alluvial Ground Water Systems ..........................................3­34

3.5.4 Springs Within and Adjacent to the EIS Analysis Area ..........................3­34

3.5.4.1 O’Brien Spring .......................................................................................3­34

3.5.4.2 Corral Creek Spring ..............................................................................3­35

3.5.4.3 Ayers Draw Spring ................................................................................3­35

3.5.4.4 Miller Bend Spring................................................................................3­36

3.5.4.5 Alkali Flat Spring #1 ..............................................................................3­36

3.5.4.6 Alkali Flat Spring #2 ..............................................................................3­36

3.5.4.7 St. Mary’s Spring ...................................................................................3­37

3.5.5 Stock Wells Within and Adjacent to the EIS Analysis Area ...................3­37

3.5.5.1 Section 19 Well......................................................................................3­37

3.5.5.2 Miller #1 Well .........................................................................................3­38

3.5.5.3 Little Shoe Well .....................................................................................3­39

3.5.5.4 Dry Ditch Well #1...................................................................................3­39

3.5.5.5 Dry Ditch Well #2...................................................................................3­39

3.5.5.6 Alkali Flat Well .......................................................................................3­39

3.5.6 Domestic Wells Within and Adjacent to the EIS Analysis Area ............3­40

3.5.6.1 ID Ranch Well.........................................................................................3­40

3.5.6.2 Boat Club “Winter” Well .......................................................................3­40

3.5.6.3 Sheller Well............................................................................................3­41

3.6 Vegetation......................................................................................................3­41

3.6.1 Vegetation Communities ..........................................................................3­41

3.6.1.1 Wyoming Sagebrush/Mixed Grass ......................................................3­41

3.6.1.2 Wyoming Sagebrush/Threadleaf Sedge............................................3­42

iv  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.6.1.3 Wyoming Sagebrush/Green Rabbitbrush .........................................3­43

3.6.1.4 Low Shrub/Mixed Grass ........................................................................3­43

3.6.1.5 Mixed Sagebrush ..................................................................................3­44

3.6.1.6 Mixed Shrub ..........................................................................................3­44

3.6.1.7 Mixed Grass............................................................................................3­45

3.6.1.8 Threadleaf Sedge/Mixed Grass............................................................3­45

3.6.1.9 Basin Big Sagebrush/Greasewood......................................................3­45

3.6.1.10 Greasewood ..........................................................................................3­46

3.6.1.11 Juniper ...................................................................................................3­46

3.6.1.12 Playas......................................................................................................3­46

3.6.1.13 Rock Outcrop/Broken Land/Miscellaneous Land Types...................3­47

3.6.1.14 Mine Area...............................................................................................3­47

3.6.2 Wetlands and Riparian Areas ....................................................................3­47

3.6.2.1 Pilot Project Produced Water Riparian and Wetland Areas...........3­49

3.6.2.2 Seeps, Springs and Stock Ponds.........................................................3­49

3.6.3 Weeds...........................................................................................................3­50

3.6.4 Threatened and Endangered Plant Species ...........................................3­51

3.6.5 Sensitive Plant Species...............................................................................3­51

3.7 Wildlife/Fisheries............................................................................................3­53

3.7.1 Big Game......................................................................................................3­53

3.7.1.1 Mule Deer...............................................................................................3­53

3.7.1.2 Elk............................................................................................................3­54

3.7.1.3 Bighorn Sheep ......................................................................................3­54

3.7.1.4 Pronghorn.............................................................................................3­54

3.7.2 Predators, Furbearers, and Small Mammals ...........................................3­55

3.7.3 Waterbirds...................................................................................................3­55

3.7.4 Raptors.........................................................................................................3­56

3.7.5 Upland Game Birds.....................................................................................3­56

3.7.6 Migratory Birds ...........................................................................................3­57

3.7.7 Fisheries .......................................................................................................3­58

3.7.8 Threatened, Endangered and Other Species of Concern....................3­59

3.7.8.1 White­tailed Prairie Dog (BLM Sensitive) ...........................................3­62

3.7.8.2 Black­footed Ferret (Federal Endangered).......................................3­63

3.7.8.3 Swift Fox (BLM Sensitive) .....................................................................3­63

3.7.8.4 White­faced Ibis (BLM Sensitive) .........................................................3­64

3.7.8.5 Trumpeter Swan (BLM Sensitive)........................................................3­64

3.7.8.6 Mountain Plover (BLM Sensitive) ........................................................3­64

3.7.8.7 Bald Eagle (Federal Threatened, Proposed for Delisting)...............3­64

3.7.8.8 Ferruginous Hawk (BLM Sensitive)......................................................3­65

3.7.8.9 Peregrine Falcon (BLM Sensitive)........................................................3­65

3.7.8.10 Greater Sage­grouse (BLM Sensitive)..................................................3­66

3.7.8.11 Long­billed Curlew (BLM Sensitive).....................................................3­66

3.7.8.12 Burrowing Owl (BLM Sensitive) ...........................................................3­67

3.7.8.13 Loggerhead Shrike (BLM Sensitive) ....................................................3­67

Seminoe Road Gas Development Project v
Draft Environmental Impact Statement November 2005

3.7.8.14 Sage Thrasher, Sage Sparrow and Brewer’s Sparrow (BLM

Sensitive)................................................................................................3­67

3.7.8.15 Northern Leopard Frog (BLM Sensitive) ............................................3­67

3.7.8.16 North Platte River Species (Federal Threatened and

Endangered)..........................................................................................3­67

3.8 Land Use..........................................................................................................3­68

3.8.1 Private and Public Lands ...........................................................................3­68

3.8.2 Rangeland....................................................................................................3­68

3.8.3 Residential and Urban Land......................................................................3­68

3.8.4 Mining ..........................................................................................................3­69

3.8.5 Recreation ...................................................................................................3­69

3.8.6 Oil and Gas ...................................................................................................3­70

3.8.7 Utilities .........................................................................................................3­70

3.8.8 Land Use Plans and Policies.......................................................................3­70

3.9 Noise................................................................................................................3­70

3.10 Cultural Resources .........................................................................................3­72

3.10.1 Introduction................................................................................................3­72

3.10.2 Cultural Chronology of the General Region...........................................3­73

3.10.2.1 Paleoindian Period ...............................................................................3­74

3.10.2.2 Archaic Period.......................................................................................3­74

3.10.2.3 Late Prehistoric Period........................................................................3­75

3.10.2.4 Protohistoric Period ............................................................................3­75

3.10.2.5 Historic Period ......................................................................................3­76

3.10.3 Summary of Previous Cultural Resource Investigations.......................3­76

3.10.3.1 Summary of Recorded Cultural Resources .......................................3­77

3.10.3.2 National Register of Historic Places Sites..........................................3­77

3.10.3.3 Prehistoric Sites ....................................................................................3­77

3.10.3.4 Historic Sites..........................................................................................3­79

3.10.3.5 Excavated Sites .....................................................................................3­80

3.10.4 Site Frequency and Distribution..............................................................3­80

3.10.5 Archaeologically Sensitive Areas..............................................................3­80

3.10.5.1 Topography and Physiography Associated With Known Sites......3­81

3.11 Recreation ......................................................................................................3­82

3.12 Transportation...............................................................................................3­83

3.12.1 Interstate 80................................................................................................3­84

3.12.2 Highway 30 (287).........................................................................................3­84

3.12.3 Highway 72..................................................................................................3­85

3.12.4 Highway 287................................................................................................3­85

3.12.5 Highway 130................................................................................................3­85

3.12.6 County Road 351 (Seminoe Road) ............................................................3­85

3.12.7 Existing Roads Within EIS Analysis Area...................................................3­86

3.13 Visual Resources.............................................................................................3­86

3.13.1 Visual Resource Management Classes......................................................3­87

3.14 Socioeconomics .............................................................................................3­88

vi Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.14.1 Population...................................................................................................3­88

3.14.2 Housing........................................................................................................3­89

3.14.3 Demographic Characteristics ...................................................................3­91

3.14.4 Employment and Economic Conditions.................................................3­93

3.14.5 Income.........................................................................................................3­94

3.14.6 Community and Public Services...............................................................3­95

3.14.6.1 Education...............................................................................................3­96

3.14.6.2 Law Enforcement................................................................................3­96

3.14.6.3 Fire Protection.....................................................................................3­97

3.14.6.4 Ambulance ...........................................................................................3­97

3.14.6.5 Hospital and Medical Services............................................................3­98

3.14.6.6 Social Services ......................................................................................3­98

3.14.6.7 Water Supply........................................................................................3­98

3.14.6.8 Wastewater Treatment ......................................................................3­98

3.14.6.9 Solid Waste ...........................................................................................3­99

3.14.6.10 Electric Utilities ....................................................................................3­99

3.14.7 Fiscal Conditions.........................................................................................3­99

3.14.7.1 State of Wyoming Revenues .............................................................3­99

3.14.7.2 Retail Sales and Use Taxes.................................................................3­100

3.14.7.3 Property Tax.......................................................................................3­100

3.14.7.4 Severance Tax ....................................................................................3­101

3.14.7.5 Federal Royalties ...............................................................................3­101

3.14.8 Social Values ..............................................................................................3­102

Chapter 4 – Environmental Consequences

4.1 Air Quality/Climate...........................................................................................4­1

4.1.1 Effects of Alternative A (No Action) ..........................................................4­3

4.1.2 Effects Common to All Action Alternatives .............................................4­3

4.1.2.1 Fugitive Dust Emissions .........................................................................4­4

4.1.2.2 Gaseous Criteria Pollutant Emissions...................................................4­4

4.1.2.3 Hazardous Air Pollutant Emissions.......................................................4­6

4.1.2.4 Visibility....................................................................................................4­6

4.1.2.5 Indirect Impacts .....................................................................................4­6

4.1.3 Cumulative Impacts .....................................................................................4­7

4.1.4 Effects of Alternative B (Proposed Action) ............................................4­10

4.1.5 Effects of Alternative C (Pipeline to Reservoir) .....................................4­10

4.1.6 Effects of Alternative D (Underground Injection).................................4­11

4.1.7 Potential Monitoring and Mitigation ......................................................4­11

4.2 Soils .................................................................................................................4­11

4.2.1 Effects of Alternative A (No Action) ........................................................4­12

4.2.2 Effects Common to All Action Alternatives ...........................................4­12

4.2.2.1 Saline/Sodic Soils...................................................................................4­14

4.2.2.2 Soils Overlying Steep Slopes ...............................................................4­15

4.2.2.3 Shallow Soils ....................................................................................... 4­16

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Draft Environmental Impact Statement November 2005

4.2.2.4 Highly Erodible Soils.............................................................................4­16

4.2.2.5 Indirect Effects Common to All Action Alternatives ......................4­17

4.2.3 Effects of Alternative B (Proposed Action) ............................................4­17

4.2.4 Effects of Alternative C (Pipeline to Reservoir) .....................................4­18

4.2.5 Effects of Alternative D (Underground Injection).................................4­19

4.2.6 Cumulative Impacts ...................................................................................4­19

4.2.7 Potential Monitoring and Mitigation ......................................................4­19

4.3 Geology...........................................................................................................4­20

4.3.1 Effects of Alternative A (No Action) ........................................................4­20

4.3.2 Effects Common to All Action Alternatives ...........................................4­20

4.3.3 Effects of Alternative B (Proposed Action) ............................................4­21

4.3.4 Effects of Alternative C (Pipeline to Reservoir) .....................................4­21

4.3.5 Effects of Alternative D (Underground Injection).................................4­21

4.3.6 Cumulative Impacts ...................................................................................4­21

4.3.7 Potential Monitoring and Mitigation ......................................................4­22

4.4 Surface Water.................................................................................................4­22

4.4.1 Effects of Alternative A (No Action) ........................................................4­23

4.4.2 Effects Common to All Action Alternatives ...........................................4­25

4.4.3 Effects of Alternative B (Proposed Action) ............................................4­27

4.4.3.1 Effects to Ephemeral Drainages Within the EIS Analysis Area.......4­28

4.4.3.2 Effects From Intensive Erosion Management of Ephemeral

Drainage Channels................................................................................4­29

4.4.3.3 Effects to Intermittent Drainages Within the EIS Analysis Area....4­31

4.4.3.4 Effects to Playas Within the EIS Analysis Area..................................4­32

4.4.3.5 Effects to North Platte River Upstream of Seminoe Reservoir.....4­33

4.4.3.6 Effects to Seminoe Reservoir .............................................................4­34

4.4.3.7 Effects to “Miracle Mile........................................................................4­35

4.4.3.8 Effects to North Platte River Downstream of Pathfiner

Reservoir................................................................................................4­36

4.4.4 Effects of Alternative C (Pipeline to Reservoir) .....................................4­36

4.4.5 Effects of Alternative D (Underground Injection).................................4­37

4.4.6 Indirect Effects ...........................................................................................4­37

4.4.7 Cumulative Impacts ...................................................................................4­37

4.4.8 Potential Monitoring and Mitigation ......................................................4­39

4.5 Ground Water.................................................................................................4­40

4.5.1 Overview of Ground Water Model...........................................................4­40

4.5.2 Effects of Alternative A (No­Action) ........................................................4­41

4.5.2.1 Effect to Mesaverde Coal Bearing Formations (Lower

Formation).............................................................................................4­42

4.5.2.2 Effects to Medicine Bow/Fox Hills Coal Bearing Formation

(Upper Formation)................................................................................4­42

4.5.2.3 Effects to Alluvial Ground Water Systems Within and Adjacent

to EIS Analysis Area...............................................................................4­42

4.5.2.4 Effects to Springs Within and Adjacent to the EIS Analysis Area..4­43

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November 2005 Draft Environmental Impact Statement

4.5.2.5 Effects to Stock Wells Within and Adjacent to the EIS Analysis

Area ........................................................................................................4­43

4.5.2.6 Effects to Domestic Wells Within and Adjacent to the EIS

Analysis Area .........................................................................................4­43

4.5.3 Effects Common to All Action Alternatives ...........................................4­43

4.5.4 Effects of Alternative B (Proposed Action) ............................................4­44

4.5.4.1 Effects to Mesaverde Coal Bearing Formation (Lower

Formation).............................................................................................4­45

4.5.4.2 Effects to Medicien Bow/Fox Hills Coal Bearing Formation

(Upper Formation)................................................................................4­45

4.5.4.3 Effects to Alluvial Ground Water Systems WIhtin and Adjacent

to EIS Analysis Area...............................................................................4­45

4.5.4.4 Effects to Springs Within and Adjacent to the EIS Analaysis Area4­45

4.5.4.5 Effects to Stock Wells Within and Adjacent to the EIS Analysis

Area ........................................................................................................4­46

4.5.4.6 Effects to Domestic Wells Within and Adjacent to the EIS

Analysis Area .........................................................................................4­47

4.5.5 Effects of Alternative C (Pipeline to Reservoir ......................................4­47

4.5.6 Effects of Alternative D (Underground Injection).................................4­48

4.5.6.1 Effects to Mesaverde Coal Bearing Formation (Lower

Formation).............................................................................................4­49

4.5.6.2 Effects to Medicine Bow/Fox Hills Coal Bearing Formation

(Upper Formation)................................................................................4­49

4.5.6.3 Effects to Alluvial Ground Water Systems Within and Adjacent

to EIS Analysis Area...............................................................................4­49

4.5.6.4 Effects to Springs Within and Adjacent to the EIS Analysis Area..4­49

4.5.6.5 Effects to Stock Wells Within and Adjacent to the EIS Analysis

Area ........................................................................................................4­50

4.5.6.6 Effects to Domestic Wells Within and Adjacent to the EIS

Analysis Area .........................................................................................4­50

4.5.7 Indirect Effects ...........................................................................................4­50

4.5.8 Cumulative Impacts ...................................................................................4­50

4.5.9 Potential Monitoring and Mitigation ..................................................... 4­51

4.6 Vegetation......................................................................................................4­52

4.6.1 Effects of Alternative A (No Action) ........................................................4­53

4.6.2 Effects Common to All Action Alterantives ...........................................4­54

4.6.2.1 Upland Vegetation ...............................................................................4­54

4.6.2.2 Wetland and Riparian Vegetation......................................................4­56

4.6.2.3 Weeds.....................................................................................................4­56

4.6.2.4 Sensitive Plant Species.........................................................................4­57

4.6.2.5 Threatened and Endangered Plant Species .....................................4­57

4.6.3 Effects of Alterantive B (Proposed Action) ............................................4­57

4.6.4 Effects of Alternative C (Pipeline to Reservoir) .....................................4­60

4.6.5 Effects of Alternative D (Underground Injection).................................4­61

Seminoe Road Gas Development Project ix
Draft Environmental Impact Statement November 2005

4.6.6 Cumulative Impacts ...................................................................................4­61

4.6.7 Potential Monitoring and Mitigation ......................................................4­62

4.7 Wildlife/Fisheries............................................................................................4­62

4.7.1 Effects of Alternative A (No Action) ........................................................4­63

4.7.2 Effects Common to All Action Alternatives ...........................................4­64

4.7.2.1 Physical Loss of Habitat .......................................................................4­64

4.7.2.2 Displacement of Wildlife.....................................................................4­65

4.7.2.3 Habitat Fragmentation and Isolation................................................4­66

4.7.2.4 Wildlife Mortality..................................................................................4­67

4.7.2.5 Increased Competition for Wildlife and Fishery Resources...........4­68

4.7.2.6 Wildlife Threshold Classifications.......................................................4­68

4.7.2.7 Big Game................................................................................................4­69

4.7.2.8 Predators, Furbearers and Small Mammals ......................................4­70

4.7.2.9 Waterfowl..............................................................................................4­71

4.7.2.10 Raptors...................................................................................................4­71

4.7.2.11 Upland Game Birds...............................................................................4­72

4.7.2.12 Migratory Songbirds ............................................................................4­72

4.7.2.13 Fisheries .................................................................................................4­72

4.7.2.14 Sensitive Species...................................................................................4­73

4.7.2.15 Threatened and Endangered Species ...............................................4­76

4.7.3 Effects of Alternative B (Proposed Action) ............................................4­77

4.7.4 Effects of Alternative C (Pipeline to Reservoir) .....................................4­78

4.7.5 Effects of Alternative D (Underground Injection).................................4­78

4.7.6 Cumulative Impacts ...................................................................................4­79

4.7.7 Potential Monitoring and Mitigation ......................................................4­79

4.8 Land Use..........................................................................................................4­79

4.8.1 Effects of Alternative A (No Action) ........................................................4­79

4.8.2 Effects Common to All Action Alternatives ...........................................4­80

4.8.3 Effects of Alternative B (Proposed Action) ............................................4­82

4.8.4 Effects of Alternatives C (Pipeline to Reservoir) and D

(Underground Injection) ...........................................................................4­83

4.8.5 Cumulative Impacts ...................................................................................4­83

4.8.6 Potential Monitoring and Mitigation ......................................................4­83

4.9 Noise................................................................................................................4­83

4.9.1 Effects of Alternative A (No Action) ........................................................4­84

4.9.2 Effects Common to All Action ALterntaives ..........................................4­84

4.9.3 Effects of Alternatives B, C and D ............................................................4­86

4.9.4 Cumulative Impacts ...................................................................................4­86

4.9.5 Potential Monitoring and Mitigation ......................................................4­86

4.10 Cultural Resources .........................................................................................4­86

4.10.1 Effects of Alternative A (No Action) ........................................................4­86

4.10.2 Effects Common to All Action Alterntaives ...........................................4­87

4.10.3 Effects of Alternatives B, C and D ............................................................4­88

4.10.4 Cumulative Impacts ...................................................................................4­88

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November 2005 Draft Environmental Impact Statement

4.10.5 Native American Consultation..................................................................4­88

4.10.6 Potential Monitoring and Mitigation ......................................................4­89

4.11 Recreation ......................................................................................................4­89

4.11.1 Effects of Alternative A (No Action) ........................................................4­89

4.11.2 Effects Common to All Action Alterntaives ...........................................4­90

4.11.3 Effects of Alternatives B, C and D ............................................................4­92

4.11.4 Cumulative Impacts ...................................................................................4­92

4.11.5 Potential Monitoring and Mitigation ......................................................4­92

4.12 Transportation...............................................................................................4­92

4.12.1 Effects of Alternative A (No Action) ........................................................4­93

4.12.2 Effects Common to All Action Alterntaives ...........................................4­93

4.12.2.1 Public Access .........................................................................................4­95

4.12.2.2 Traffic Load ...........................................................................................4­95

4.12.2.3 Public Safety..........................................................................................4­96

4.12.2.4 Environmental Safety..........................................................................4­97

4.12.2.5 Road Maintenance................................................................................4­97

4.12.2.6 Indirect Effects .....................................................................................4­98

4.12.3 Effects of Alternatives B, C and D ............................................................4­98

4.12.4 Cumulative Impacts ...................................................................................4­98

4.12.5 Potential Monitoring and Mitigation ......................................................4­98

4.13 Visual Resources.............................................................................................4­98

4.13.1 Effects of Alternative A (No Action) ......................................................4­100

4.13.2 Effects Common to All Action ALterntaives ........................................4­100

4.13.3 Effects of Alternatives B, C and D ..........................................................4­102

4.13.4 Cumulative Impacts .................................................................................4­102

4.13.5 Potential Monitoring and Mitigation ....................................................4­102

4.14 Socioeconomics ...........................................................................................4­102

4.14.1 Effects of Alternative A (No Action) ......................................................4­104

4.14.2 Effects Common to All Action Alterntaives .........................................4­104

4.14.2.1 Employment .......................................................................................4­104

4.14.2.2 Income (Wages)...................................................................................4­105

4.14.2.3 Population...........................................................................................4­107

4.14.2.4 Housing................................................................................................4­108

4.14.2.5 Community and Public Services.......................................................4­109

4.14.2.6 Fiscal Conditions .................................................................................4­109

4.14.2.7 Social Values ........................................................................................4­113

4.14.3 Effects of Alternative B (Proposed Action) ..........................................4­114

4.14.4 Effects of Alternative C (Pipeline to Reservoir) ...................................4­114

4.14.5 Effects of Alternative D (Underground Injection)...............................4­114

4.14.6 Cumulative Impacts .................................................................................4­114

4.14.7 Potential Monitoring and Mitigation ....................................................4­115

4.15 Accidents and Spills.....................................................................................4­115

4.16 Irreversible and Irretrievable Commitment of Resources .....................4­116

4.16.1 Irreversible Resource Commitment ......................................................4­117

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Draft Environmental Impact Statement November 2005

4.16.2 Irretrievable Resource Commitment ....................................................4­118

4.17 Unavoidable Adverse Effects .....................................................................4­118

4.18 Short­Term Use Versus Long­Term Productivity......................................4­118

Chapter 5 – List of Agencies, Organizations and Individuals to

Whom Copies of the EIS Were Sent

5.1 Federal Agencies..............................................................................................5­1

5.2 Tribal Governments.........................................................................................5­2

5.3 Elected Officials ...............................................................................................5­3

5.4 State Government ...........................................................................................5­3

5.5 County and Local Government ......................................................................5­4

5.6 Businesses and Organizations ........................................................................5­4

5.7 Individuals ........................................................................................................5­8

Chapter 6 – List of Preparers

6.1 Introduction.....................................................................................................6­1

6.2 Bureau of Land Management.........................................................................6­1

6.3 Saratoga – Encampment – Rawlins Conservation District ..........................6­1

6.4 S. Edwards Inc. .................................................................................................6­1

6.5 S. Edwards Inc. Primary Consultants .............................................................6­2

Chapter 7 – References

Chapter 8 – Glossary

Chapter 9 – Index

xii Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

List of Tables

Chapter 1

1­1 Critical Elements Not Considered in Detail............................................1­6

Chapter 2

2­1 Preliminary Estimate of Surface Area Disturbance..............................2­3

2­2 Raptor Nest Protection Dates ...............................................................2­26

2­3 Alternate Water Treatment Methods ..................................................2­39

2­4 Summary of Impacts by Alternative for Each Issue...........................2­40

Chapter 3

3.1­1 Temperature and Precipitation Data for Rawlins, Wyoming .............3­2

3.1­2 Ambient Air Quality Standards and Air Increments.............................3­3

3.1­3 Representative Background Ambient Air Concentrations .................3­4

3.1­4 2001 Measured Acid Deposition Data.....................................................3­4

3.1­5 Monitored Background Conditions at Sensitive Lakes ........................3­5

3.4­1 Summary of Surface Water Classes and Uses ......................................3­15

3.4­2 Intermittent Drainage Watershed Characteristics.............................3­21

3.4­3 Erosion Potential of Proposed Discharge Drainages .........................3­23

3.4­4 Ephemeral Drainage Watershed Characteristics ................................3­25

3.4­5 Playa Characteristics Summary .............................................................3­29

3.5­1 Spring Information.................................................................................3­35

3.5­2 Well Information .....................................................................................3­38

3.6­1 Vegetation Communities .......................................................................3­42

3­6­2 State of Wyoming Designated Noxious Weeds, BLM Weedy Species

of Concern, and Carbon County Declared Weeds Known to Occur

in the EIS Analysis Area...........................................................................3­52

3.7­1 Threatened, Endangered and BLM Sensitive Species Potentially

Occurring Within the EIS Analysis Area ................................................3­59

3.8­1 Allotment Summary ...............................................................................3­69

3.9­1 Typical Range of Common Sounds.......................................................3­71

3.9­2 Permissible Occupational Noise Exposures .........................................3­73

3.10­1 Prehistoric Chronology of the Wyoming Basin..................................3­74

3.10­2 Historic Chronology of the Wyoming Basin........................................3­76

3.10­3 Summary of Prehistoric and Historic Sites Within the Seminoe

Road Analysis Area ..................................................................................3­78

3.12­1 Traffic Counts for 2003...........................................................................3­84

3.14­1 Historic Populations................................................................................3­89

3.14­2 Population Trends...................................................................................3­89

3.14­3 Housing Profile: 2000..............................................................................3­89

3.14­4 Average Household Size: 2000...............................................................3­90

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Draft Environmental Impact Statement November 2005

3.14­5 Housing Values and Costs: 2000.............................................................3­91

3.14­6 General Demographic Characteristics: 2000........................................3­92

3.14­7 Educational Attainment: 2000...............................................................3­93

3.14­8 Employment Status: 2000 ......................................................................3­94

3.14­9 School Enrollment ..................................................................................3­96

Chapter 4

4.1­1 Maximum Modeled PM10 and PM2.5 Impacts...........................................4­4

4.1­2 Maximum Modeled SO2 Impacts..............................................................4­5

4.1­3 Maximum Modeled O2 Impacts................................................................4­6

4.1­4 Maximum Modeled NO2 and CO Impacts – Alternative C...................4­10

4.1­5 Maximum Modeled Formaldehyde Impacts .......................................4­10

4.1­6 Long­term Formaldehyde Cancer Risk Analysis..................................4­11

4.2­1 Soil Impacts by Alternative....................................................................4­12

4.4­1 Pilot Project NPDES Limits......................................................................4­23

4.4­2 Summary of Potential Discharge Locations ........................................4­27

4.4­3 Erosion Potential of Proposed Discharge Drainages .........................4­29

4.4­4 Estimates of Produced Water Discharge Into Playas .........................4­32

4.5­1 Potential Flow Reduction at Springs (Alternatives B and C) .............4­46

4.5­2 Potential Water Level Reduction at Stock Wells (Alternatives

B and C) .....................................................................................................4­47

4.5­3 Potential Water Level at Domestic Wells (Alternatives B and C).......4­47

4.5­4 Potential Flow Reduction at Springs (Alternative D)..........................4­49

4.5­5 Potential Water Level Reduction at Stock Wells (Alternative D).......4­50

4.6­1 Vegetation Impact Acreage Estimates.................................................4­53

4.8­1 Grazing Allotment Impact Summary....................................................4­81

4.9­1 Equipment Noise Levels .........................................................................4­84

4.9­2 Noise Impacts Versus Distance ..............................................................4­85

4.12­1 Accident Data: Carbon County Road 351 (1999­2003).........................4­96

4.12­2 Accident Data: Interstate 80 Walcott to Rawlins (1999­2003)............4­96

4.14­1 Employment Assumptions ..................................................................4­105

4.14­2 Estimated Payroll Income....................................................................4­106

4.14­3 Population Increase Potential.............................................................4­107

4.14­4 Estimated Revenues and Costs ...........................................................4­110

4.14­5 Projected Tax Revenues & Royalties...................................................4­111

xiv  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

List of Figures

Please note – All figures are located in the separate figure volume

1 General Location Map

2 Surface Ownership Map

3 Mineral (Oil and Gas) Lease Map

4 General Layout Map

5 Projected Build­out Scenario (Mesaverde Formation)

6 Projected Build­out Scenario (Medicine Bow and Fox Hills Formations)

7 Typical Access Road

8 Typical Well Pad Layout During Drilling Activities

9 Typical Producing Well Layout

10 Compressor Station Layout

11 Water Treatment Facilities Layout

12 Produced Water Discharge Points – Alternative B

13 Conceptual Details for Erosion Management Structures

14 Direct Discharge into Seminoe Reservoir – Alternative C

15 Design Concepts for Direct Discharge – Alternative C

16 Underground Injection of Produced Water – Alternative D

17 Steep Slopes

18 Conceptual Schematic of Plugged and Abandoned Wellbore

19 Regional Activity

20 Air Quality Modeling Domain

21 Wind Rose – Rawlins, Wyoming

22 Soils Map

23 Saline and Sodic Soils

24 Steep Slope Soils

25 Shallow Soils

26 Erodible Soils

27 Areas of Sensitive Soil Concentrations

28 Regional Geology

29 General Stratigraphic Column and Geologic Cross Section A­A’

30 Platte River Drainage Basin

31 Hanna Basin

32 Summary of Flow Data

33 Hydrologic Monitoring Sites Location Map

34 Summary of Surface Water Salinity Data

35 Hydrologic Process and Geomorphic Cycle (Part I)

36 Hydrologic Process and Geomorphic Cycle (Part II)

37 Watershed Map

38 Pool Table Draw Photographs

39 Pilot Project Discharge Rates

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Draft Environmental Impact Statement November 2005

40 Pilot Project Water Quality

41 Project Water Production Schedule

42 Diagram of a Surface Water Mixing Model

43 Potential Ground Water Drawdown and Recovery (Alternatives B and C)

44 Vegetation Map

45 Wildlife Map

46 Mountain Plover and Prairie Dog Habitat

47 Grazing Allotments

48 Visual Resource Management

49 Key Observation Point No. 1

50 Key Observation Point No. 2

51 Key Observation Point No. 3

52 Key Observation Point No. 4

53 Key Observation Point No. 5

54 Carbon County Employment by Industry (1970­2000)

55 Carbon County Jobs – 1970 and 2000

56 Carbon County Personal Income (1970­2000)

57 Unemployment Rates

58 Wyoming State General Revenues (1992­2002)

59 Wyoming General Revenue Source

60 Wyoming State Tax Revenue Collection 2002 and 2003

61 Wyoming State Expenditures – 2002

62 Wyoming Severance Tax Trends (1992­2003)

xvi Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

List of Appendices

Appendix A Proponent’s Project Description

Appendix B The NEPA Process

Appendix C Great Divide Resource Management Plan Analysis

Appendix D Agency Jurisdictions (Permits and Approvals)

Appendix E Regional Activity

Appendix F Reclamation Plan

Appendix G Hazardous Materials Management Plan

Appendix H Air Quality Information

Appendix I Monitoring Results for Seminoe Road Pilot Project

Appendix J Overview of Surface Water Mixing Model

Appendix K Wildlife Monitoring and Protection Plan

Appendix L Biological Assessment

Appendix M Cultural Resource Management Plan

Appendix N Soils and Vegetation Information

Appendix O Erosion Management for Ephemeral Drainages

Seminoe Road Gas Development Project xvii
November 2005 Draft Environmental Impact Statement 

Chapter 1 – Purpose of and Need for Action

1.1 Introduction 

Dudley & Associates, LLC (referred to as the Proponent) proposes to develop and operate a 

coalbed natural gas project in the northwest part of the Hanna Basin in Carbon County, Wyoming, 

approximately 20 miles northeast of Rawlins. See Figure 1, General Location Map. 

The proposed operation is identified as the Seminoe Road Gas Development (Seminoe Road) 

Project. This Project considers up to 1,240 wells, drilled on up to 785 well pad sites, spaced at 

approximately one well pad site for every 160 acres (4 wells per square mile). Associated facilities 

would include access roads, gas and water collection pipelines, compressor stations, water 

disposal systems and an electric power supply system. See Appendix A, Proponent’s Project 

Description. 

The project area totals approximately 137,000 acres and involves a checkerboard pattern of 

mostly federal (greater than 49%) and private (greater than 49%) surface, with some state lands 

(less than 1%). See Figure 2, Surface Ownership Map. The Proponent owns or controls mineral 

(oil and gas) interests comprising approximately 80% of the project area. The Bureau of Land 

Management (BLM) manages the federal mineral estate underlying the public lands administered 

by the BL Rawlins Field Office. See Figure 3, Mineral (Oil & Gas) Lease Map. 

1.2 Background 

During the summer of 2001, the Proponent completed construction of the Seminoe Road Coalbed 

Methane Pilot Project (Pilot Project) to determine the commercial feasibility of producing gas from 

coal formations. Sixteen pilot production wells and one pressure observation well were installed. 

Many of these wells have begun to produce small amounts of gas. Although the Pilot Project 

production results are still being analyzed, the Proponent has decided to plan for further natural 

gas development within their lease holdings in the area. 

The BLM previously prepared an environmental analysis (EA) for the Pilot Project (WY-030-EA00­

288). In addition, the installation of a compressor facility and a 20 mile-long high-pressure pipeline 

from the Pilot Project to a commercial interconnect near Walcott, Wyoming are discussed in the 

Seminoe Road Natural Gas Gathering Pipeline/Access Road and Compressor Station/Storage 

Seminoe Road Gas Development Project 1-1 
Draft Environmental Impact Statement November 2005 

Yard/Access Road (Pipeline) Project EA (WY-030-EA2-229). The BLM approved their 

construction in 2002; installation is pending further Pilot Project results. 

In September 2002, the Proponent notified the BLM Rawlins Field Office of its desire to continue 

to drill and develop natural gas wells in the lands surrounding the Pilot Project. With the 

Proponent’s notification, the BLM determined that the requirements of the National Environmental 

Policy Act (NEPA) would be best served by preparing an environmental impact statement (EIS) for 

the proposed full-scale project. The BLM is serving as the lead agency for preparation of the EIS, 

which is designed to inform the public of the potential environmental consequences of the project, 

present a range of reasonable alternatives, and assist in determining mitigation measures to be 

employed for protection of non-gas resources. 

1.3 Purpose and Need 

The Proponent’s purpose for the Seminoe Road Project is the economical recovery and sale of 

natural gas resources to U.S. markets. This project is consistent with the National Energy Policy. 

America’s need for energy continues to grow, and natural gas has emerged as an important 

industrial and domestic fuel source. The development of domestic gas reserves reduces the 

country’s dependence on foreign sources of energy and maintains a supply of fuel for domestic 

consumption, industrial production, power generation, and national security. Natural gas 

development has also historically been, and continues to be, an important and integral part of the 

state and local economies in Wyoming. 

The BLM, as agent for the U.S. Secretary of the Interior, has responsibility for managing federally 

owned gas resources. For more than 100 years, it has been federal policy to make lands available 

for mineral exploration and development. Privately owned gas resources are likely to continue to 

be developed, regardless of gas development on federal lands. 

1.4 EIS Scoping Process 

The BLM announced their intent to prepare the Seminoe Road Project EIS in the Federal Register 

on March 13, 2003. 

The BLM conducted two public meetings during a 60-day comment period to solicit comments on 

the Seminoe Road Project. These meetings were held on May 7, 2003, at the Town Hall in Hanna, 

1-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Wyoming, and on May 8, 2003 at the BLM Rawlins Field Office in Rawlins, Wyoming. Eighteen 

letters were received during the scoping process. 

Scoping documents, containing more detail about the scoping process, are on file at the BLM 

Rawlins Field Office in Rawlins, Wyoming. Additional information about the EIS process employed 

for the Seminoe Road Project is set forth in Appendix B, The NEPA Process. 

1.5 Issues and Concerns 

The issues and concerns for the Seminoe Road Project, follow. Key issues, as designated by the 

BLM interdisciplinary (ID) team, are denoted with an asterisk (*). 

1.5.1 Air Quality* 

Identify and mitigate project-related air quality impacts. Areas of consideration are fugitive 

dust and gaseous emissions affecting air quality; activities that affect state and federal public 

health and welfare standards; and those activities affecting visibility protection standards in highly 

valued areas (e.g. National Parks and Wilderness Areas). 

1.5.2 Cultural Resources 

Identify cultural resources, minimize disturbance impacts to these resources, and, as 

appropriate, conduct Native American consultation. Areas of consideration are the effects to 

historic properties listed or eligible for listing on the National Register of Historic Places. 

1.5.3 Hydrology (Surface and Ground Water)* 

Identify and mitigate surface and ground water impacts to ensure surrounding watersheds 

are protected and maintained. Areas of consideration are the potential erosion in ephemeral 

drainages resulting from produced water surface discharge, potential alteration to existing 

hydrologic systems, specifically project drainages and area aquifers; potential changes in 

downstream water flow rates; and potential alterations to North Platte River and Seminoe 

Reservoir water chemistry. 

1.5.4 Land Use* 

Minimize land disturbances and consider issues arising from area surface and mineral 

ownership differences. Areas of consideration are the acreage to be disturbed by the Seminoe 

Seminoe Road Gas Development Project 1-3 
Draft Environmental Impact Statement November 2005 

Road project, including the amount of disturbance to BLM, state and private land; effects on area 

livestock grazing; and possible future land use changes. 

1.5.5 Noise 

Identify and mitigate noise impacts. Areas of consideration are construction traffic and project 

development noise levels; compressor and generator operation noise levels; effects of projectrelated noise on Seminoe Reservoir recreational activities and area wildlife. 

1.5.6 Weeds 

Minimize the introduction and spread of weeds in the project area. Areas of consideration are 

the introduction and/or spread of weeds where project activities disturb the land; and the 

implementation of reclamation, use of innovative weed control methods (goats, mechanical, etc.) 

and careful herbicide use to avoid water quality, wildlife and vegetation impacts to plants not 

targeted for control. 

1.5.7 Public and Worker Health and Safety 

Protect worker health and safety. Areas of consideration are health and safety risks from project 

activities and accidents necessitating emergency responses. 

1.5.8 Recreation 

Mitigate impacts on recreational activities. Areas of consideration are project-related 

disruptions to recreational activities including hunting, fishing and boating, the potential for 

increased access to the Seminoe Reservoir and North Platte River, and potential impacts to 

outfitted (commercial guided) hunting on the checkerboard surface ownership within the EIS 

analysis area where legal public access is limited. 

1.5.9 Roads/Transportation 

Address project construction and operations traffic impacts. Areas of consideration are the 

amount of project-related road use and traffic; project-related traffic and maintenance demands on 

Carbon County Road 351; new roads necessary for serving well pads and compressor sites; 

possible access impacts to Western Area Power Authority’s (WAPA) electric transmission line that 

traverses the project area; and project-related traffic accident increases. 

1-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

1.5.10 Socioeconomics 

Address the social and economic impacts on Carbon County residents. Areas of 

consideration are project-related income generation and nearby community impacts, including 

those on housing, utilities, employment, public services, tax and governmental revenues, and 

present lifestyles and quality of life. 

1.5.11 Soils 

Identify and minimize project-related impacts. Areas of consideration are project-related soil 

erosion increases and sedimentation, particularly from produced water and at construction 

activities; potential soil chemistry changes or soil quality degradation from produced water; and 

alterations in the ability of soil to support revegetation. 

1.5.12 Vegetation 

Address project-related impacts to vegetation and wetlands. Areas of consideration are the 

potential impacts to the vegetation communities within the EIS analysis area, including impacts on 

threatened, endangered or sensitive plants; avoidance, where possible, of impacts to vegetation 

within wetlands and riparian areas; and impacts to drainage vegetation affected by discharge of 

produced water. 

1.5.13 Visual Resources 

Mitigate project-related impacts on protected viewsheds. Areas of consideration are potential 

impacts of project facilities and activities on viewsheds within and adjacent to the EIS analysis 

area, including Seminoe State Park, Carbon County Road 351 (a National Back Country Byway 

from Sinclair to Alcova), Coal Creek fishing access, and from the Bennett Mountain Wilderness 

Study Area; and mitigation necessary to meet BLM Visual Resource Management (VRM) Class II 

requirements. 

1.5.14 Wildlife* 

Mitigate impacts on wildlife and wildlife habitat. Areas of consideration are potential impacts to 

certain wildlife and their habitats within and surrounding the EIS analysis area, including impacts 

on BLM species of concern and threatened, endangered, or candidate species identified by the 

U.S. Fish and Wildlife Service (USFWS). 

Seminoe Road Gas Development Project 1-5 
Draft Environmental Impact Statement November 2005 

1.6 Critical Elements Not Considered in Detail 

Table 1-1, Critical Elements Not Considered in Detail, presents those resources or elements of 

the environment that are not expected to be encountered or affected by the build-out of the 

Seminoe Road Project. Critical elements of the human environment are those subject to 

requirements specified in statute, regulation or executive order. 

Table 1-1, Critical Elements Not Considered in Detail

1 

Resource Rationale 

Areas of Critical Environmental Concerns2 

No areas of critical environmental concerns are found in the EIS 

analysis and surrounding areas so there would be no impacts by the 

proposed action or other action alternatives. 

Environmental Justice No minority or economically disadvantaged communities or 

populations are present that could be affected by the alternatives. 

Wilderness and Wilderness Study Areas 

None of the areas within and adjacent to the EIS analysis area are 

wilderness areas or identified by the BLM as Wilderness Study 

Areas. 

Prime or Unique Farmlands None present. 

Wild and Scenic Rivers None present. 

Fuels and Fire Management Negligible. As appropriate, the BLM would impose standard practices 

to control the potential for wildfires. 

Mineral Resources Project wells would be completed across coal seams. Other than 

natural gas, no mineral resources would be extracted. 

Paleontology 

Underlying bedrock may contain paleontological resources. If 

discovered during excavation for pipelines and electric utilities, work 

would be stopped at the location of the discovery, and the BLM would 

be notified. Appropriate protection and/or mitigation would be 

implemented. 

Wild Horses and Burros None present. 

Notes: 

1. Elements considered and documented as a negative declaration according to BLMH-1790-1, Appendix 5, 

1988. 

2. Areas of critical environmental concern is defined in Section 103(a) of the Federal Land Policy and 

Management Act of 1976 (43 CFR 1610). 

1.7 Decisions to be Made 

The BLM is responsible for completing this draft EIS and has followed specific established 

procedures that began with scoping and data collection and continued with analysis of data and 

evaluation of alternatives. See Appendix B, The NEPA Process. Following the close of the draft 

EIS review and comment period, the BLM will consider comments submitted by the public, 

interested organizations, and government agencies and will respond to those comments in a final 

EIS. In accordance with 40 CFR 1503.4, the BLM may decide to: 

1-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

3⁄4 Modify alternatives; 

3⁄4 Develop new alternatives; 

3⁄4 Modify the analysis; 

3⁄4 Make revisions in the final EIS; or, 

3⁄4 Explain why comments do or do not warrant further agency response. 

After the release of the final EIS, the BLM will issue a Record of Decision (ROD) regarding its 

respective decision on the proposed action or selected alternative. In the ROD, the BLM 

responsible official may decide to: 

3⁄4 Adopt the No Action Alternative; 

3⁄4 Adopt the Proposed Action (with or without additional mitigation and monitoring 

measures); 

3⁄4 Adopt an alternative with features of several of the alternatives; or, 

3⁄4 Adopt one of the action alternatives with additional mitigation and monitoring 

measures. 

1.8 Agency Responsibilities and Jurisdictions 

The proposed Seminoe Road Project gas wells would be developed in accordance with the 

Mineral Leasing Act of 1920 (Title 30; USC 181-287), Onshore Oil and Gas Leasing Act, and 43 

CFR 3101.1-2. These statutes grant the Proponent the rights to develop their federal leases. 

However, compliance with various federal, state and local statutes (including NEPA), permits, 

easements and rights-of-way (ROW) is required for any action alternative, including the proposed 

action if selected. See Appendix D, Agency Jurisdictions (Permits and Approvals). 

Consistent with lease terms and conditions, the BLM will only approve development proposals that 

minimize adverse impacts to resources. 

1.9 Conformance With BLM Land Use Plans 

The Seminoe Road Project as proposed is in conformance with the Great Divide Resource 

Management Plan (RMP) (1990). The BLM-administered land in this area is generally open space 

Seminoe Road Gas Development Project 1-7 
Draft Environmental Impact Statement November 2005 

used for oil and gas exploration and production, mineral exploration and mining, livestock grazing, 

wildlife habitat, and recreation. 

The BLM is revising the Great Divide RMP, known also as the Rawlins RMP that provides 

guidance for managing an estimated 3.5 million acres of BLM-administered public land surface 

and 4.5 million acres of federal mineral estate in Albany, Carbon, Laramie and portions of 

Sweetwater counties in southern Wyoming. A draft of the Rawlins RMP revision and draft EIS 

were released in December 2004. A final EIS is not expected to be released until mid to late 2006 

or later. 

Until the Rawlins RMP is completed and its associated ROD is issued , the BLM will manage 

proposed activities, including the Seminoe Road Project, in conformance with the Great Divide 

RMP. See Appendix C, Great Divide Resource Management Plan Analysis. 

1.10 Additional NEPA Analysis 

As explained in Appendix A, Proponent’s Project Description, the Proponent plans for 

approximately of ten distinct development phases across the entire 137,000-acre EIS analysis 

area. Prior to the implementation of any new phase or activities proposed by he Proponent on 

BLM administered lands, the BLM must process an application for permit to drill (APD), and ROW 

or other similar authorization in accordance with its policy of including additional NEPA analysis. 

These site-specific plans would include location surveys showing the specific area to be disturbed 

for access roads, well pads, utility (gas, water and electric) lines, and compressor facilities. Each 

submittal must comply with the general terms and conditions outlined in the ROD that will be 

issued as part of this EIS process, as well as the approved BLM RMP. Also see Section 2.4.1, 

Planning and Pre-Construction Activities and Appendix D, Agency Jurisdictions (Permits and 

Approvals). 

1.11 Regional Activity 

A number of activities occur in the region within and surrounding the proposed Seminoe Road 

Project. These activities include mining, oil and gas development, oil refining, gas and oil 

pipelines, electric power generation, railroad and highway ROWs, ranching and recreation. A 

discussion of these activities is set forth in Appendix E, Regional Activity. 

1-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Chapter 2 - Alternatives Including the Proposed Action

2.1 Introduction 

The BLM explored and evaluated various ideas and options during the selection and 

development of alternatives for this draft EIS. The alternatives considered in detail in this chapter 

are a no action alternative, the proposed action, and two other action alternatives. A discussion of 

reclamation and environmental management, mitigation and monitoring measures is included. 

The environmental consequences associated with each of the alternatives are analyzed in 

Chapter 4, Environmental Consequences. 

To assist in the development of alternatives for this draft EIS, representatives from the BLM, 

cooperating agencies and interested government agencies met numerous times in 2002 through 

2005, and visited the project area on many occasions to become familiar with the Pilot Project 

operations, existing conditions, and surrounding areas. 

2.2 No Action Alternative (Alternative A) 

NEPA regulations require that EIS alternative analyses in the EIS “include the alternative of no 

action” (40 CFR 1502.14(d)). For this analysis, “no action” means that the BLM would reject the 

Proponent’s proposal and the proposed activity would not take place. 

2.3 Formulation of Action Alternatives 

The BLM ID team met on August 4, October 9 and December 9, 2003, to consider possible EIS 

alternatives that might have lesser environmental impacts than the proposed action. The key 

issue that drove alternative development was the Proponent’s proposal to dispose of produced 

water by discharging it directly into ephemeral draws as was proposed with the Seminoe Pilot 

Project. Field observations made in 2004 and 2005 found that produced water that was being 

directly discharged into ephemeral drainages was causing soil erosion and had possibly 

accelerated natural “headcutting” or erosion of the soil or stream channel that recedes towards 

the point of discharge. A number of options were identified. Alternatives were eliminated from 

consideration if they clearly could not meet the purpose and need for the project, did not address 

the identified issues, were impractical or unreasonable, did not respond to public and agency 

concerns, or did not satisfy NEPA regulations. 

Seminoe Road Gas Development Project 2-1 
Draft Environmental Impact Statement November 2005

Those action alternatives screened from detailed evaluation, as well as a synopsis of the reasons 

for their dismissal, are delineated in Section 2.10, Alternatives Considered but Eliminated From 

Detailed Evaluation. 

In addition to the no action alternative (Alternative A), the BLM has chosen to analyze three 

“action” alternatives in detail in this draft EIS: 

3⁄4 Proposed Action (Alternative B); 

3⁄4 Direct Discharge of Produced Water Into Seminoe Reservoir (Alternative C); and 

3⁄4 Underground Injection of Produced Water (Alternative D). 

2.4 Alternative B – Proposed Action 

Alternative B presents the actions proposed by the Proponent for the development, operation and 

reclamation of the gas extraction project. The detailed description of the Seminoe Road Project is 

set forth in Appendix A, Proponent’s Project Description. 

The Proponent proposes to drill up to 1,240 natural gas wells on up to 785 well pad locations, 

which are spaced at one well pad site every 160 acres. Development would also require 

construction of access roads, gas and water collection lines, electric utility lines, water treatment 

and discharge facilities, and compressor stations. Figure 4, General Layout Map, illustrates the 

tentative locations of well pad sites and access roads to be installed over the development phase 

of the project. 

The Proponent plans to initiate field development in early 2006 following satisfaction of NEPA and 

other federal, state and local regulatory approvals. The life of the project is anticipated to be 30 

years; this timeframe would include development, operations, and final decommissioning and 

reclamation work. Disturbance projections for the project are set forth in Table 2-1, Preliminary 

Estimate of Surface Area Disturbance. 

Gas from two distinct coal formations (the Mesaverde and Medicine Bow/Fox Hills formations) 

would be produced in separate well bores, which would share a common well pad. Sharing well 

pads would minimize disturbed land surface in the development of the two formations and require 

less construction activity. 

2-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Table 2-1, Preliminary Estimate of Surface Area Disturbance


Facility 

Initial Disturbance Area2 

(acres) 

Operational Disturbance Area3 

(acres) 

Drill Pads 4 1,727 785 

Access Roads5 2,854 1,427 

Utilities6 1,427 0 

Water Discharge Facilities7 79 79 

Erosion Management Facilities8 57 28 

Compressor Facilities9 30 30 

Total Disturbed Area 6,174 2,349 

Percentage Disturbance of Total Project Area10 4.5% 1.7% 

Notes: 

1. This table presents the total area estimated to be disturbed within the Seminoe Road Project during the 

projected 30-year life of the project. 

2. The initial disturbance represents the area disturbed as a result of drill pad construction, access roads, gas, 

water and utility rights-of-way, compressor stations, and treated water-handling systems. 

3. Part of the area initially disturbed by drilling operations would be reclaimed (~55%) shortly after each well is 

completed and equipped. The area not reclaimed would be used for ongoing operations. Once the gas 

resource is depleted, facilities would be removed and the balance of the drill pad would then be reclaimed. 

4. An estimated 785 drill pads would be created in the project area. area needed for drilling operations would 

average about 2.2 acres for each well pad location. Subsequent reclamation would reduce the drill pad size 

to approximately 1 acre, the area needed for production operations. 

5. Each drill pad would require an estimated average 0.6 miles of access road for which an estimated width of 

50 feet will be physically affected by the construction process. Fifty percent of the area initially disturbed by 

road construction (25’) would be reclaimed following construction activities. Access roads would remain in 

service for the life of the project. 

6. “Utilities” include gas and water collection pipelines, power lines and their ancillary facilities, and 

communications lines. Utilities corridors are ordinarily laid out parallel to and installed simultaneously with 

the access roads, initially utilizing an average width of 25 feet and an estimated average 0.6 miles length for 

each drill pad. Once utilities are installed and buried, the disturbed areas would be fully reclaimed. 

7. The measured surface disturbance at the Pilot Project for DS-1, DS-2 and DS-3 water treatment facilities is 

1.26 acres serving sixteen wells. Experience indicates that the construction, installation, and operation of 

water discharge facilities would entail an average disturbance of 0.1 acre allocated to each drill pad. These 

facilities would remain in service for the life of the project. 

8. The Proponent did not include erosion control and management for ephemeral drainages below produced 

water discharge points as part of its proposed action. Given potential erosion concerns in the ephemeral 

drainages down-drainage of where produced water would be released, the BLM is considering possible 

mitigation that would include erosion control management facilities and structures, such as Gabions, 

concrete weirs, sheet piling, grade control, or other similar structures, as necessary to minimize erosion in 

ephemeral drainages resulting from produced water. To inform agency decision makers and the public, the 

BLM has made an estimate of the possible acreage that might be disturbed as a result of the installation of 

such erosion control management structures. See Appendix O, Erosion Management for Ephemeral 

Drainages. Actual engineering design and siting of possible erosion control management structures would 

be completed as necessary for each phase of the proposed project build-out. 

9. It is also presumed that three compressor stations would be required to adequately serve the project, each 

requiring an estimated 10 acres, for a total projected disturbance of 30 acres. 

10. This percentage is based on an estimated 137,000 acres within the EIS analysis area. 

Field development and drilling would occur in a phased sequence as illustrated on Figure 5, 

Projected Build-out Scenario (Mesaverde Formation), and on Figure 6, Projected Build-out 

Scenario (Medicine Bow and Fox Hills Formations). The actual timing of field development 

and operations could be affected by the availability of drilling contractors and other third-party 

services, oil and gas lease acquisition, regulatory requirements and stipulations, contractual 

obligations, weather, and commodity prices. 

Seminoe Road Gas Development Project 2-3 
Draft Environmental Impact Statement November 2005

2.4.1 Planning and Pre-Construction Activities 

The Proponent plans for approximately ten distinct development phases across the entire 

137,000-acre EIS analysis area. See Figure 5, Projected Build-out Scenario (Mesaverde 

Formation), and Figure 6, Projected Build-out Scenario (Medicine Bow and Fox Hills 

Formations). 

Each phase would be individually assessed and approved by the BLM with site-specific NEPA 

analysis and environmental reviews. Experience and knowledge gained from each phase would 

be applied to better planning and implementation of each subsequent phase. 

Prior to the start of a new phase of construction and drilling, the Proponent would submit a sitespecific APD plan of development and ROW applications to the BLM that would include a 

description of the activities to be conducted and/or completed in the forthcoming phase. These 

applications would conform to BLM regulations and include site-specific plans for the drilling, 

testing, completing and equipping process including but not limited to location surveys showing 

the exact area for access roads, well pads, and ancillary facilities (gas/water/electric lines; 

compressor stations, water treatment and discharge facilities, etc.). 

To support BLM’s efforts to review the applications, the Proponent would stake proposed 

development sites in the field. The BLM would inspect these staked sites to ensure consistency 

with the application and that environmental resources are evaluated such that proposed 

operations comply with the governing RMP and any EIS decisions made for the Seminoe Road 

Project. The BLM would undertake subsequent NEPA analysis tied to this EIS, as necessary. See 

Section 1.10, Additional NEPA Analysis. 

As appropriate, the applications for construction and development activities would be revised per 

negotiations with the BLM. The BLM may approve or deny site-specific proposals, and any 

conditions of approval would be attached to and become part of each permit. Upon receipt of final 

BLM site-specific NEPA review and approval, the Proponent could commence with the specific 

approved activities, as long as other applicable federal, state and local permits are obtained. 

2.4.2 Roads 

Up to approximately 470 miles of roads would be necessary to access Seminoe Road Project 

well pad sites and ancillary support facilities at the time of full project build-out. Of this total, 

2-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

approximately 200 miles of existing roads would be upgraded to access those sites, and an 

estimated 270 miles of new roads would be constructed. Rock aggregate, such as sand and 

gravel, would be used to surface roads to benefit year-round use, which would allow the transport 

of heavy loads, minimize dust generation and reduce road maintenance. 

BLM road standards are set forth in BLM Manual 9113; these standards would be applied to new 

and upgraded roads on both BLM and fee (private) lands, although the Proponent would consider 

the private landowner needs for roads on private lands. See Section 2.8.7, Road Construction/ 

Transportation. Depending primarily on traffic and volume, the BLM standards provide for three 

different functional classifications: 

Collector roads provide primary access to large blocks of land and connect with or are 

extensions of a public road system. They generally receive the highest volume of traffic of 

the roads in the BLM road system. 

Local roads normally serve a smaller area than collector roads and connect either to 

collector roads or public road systems. Local roads receive lower volumes, carry fewer 

traffic types, and generally serve fewer users than collector roads. These local roads can be 

single lane roads with turnouts. 

Resource roads normally are single lane spur roads that provide point (well pad) access 

and connect to local or collector roads. They carry very low volume and accommodate only 

one or two types of use. 

Roads within the EIS analysis area would be single lane (14-foot gravel surface) all-weather local 

and resource roads, with turnouts as necessary on the local roads. They would be used by the 

Proponent employees and contractors, BLM and other governmental personnel, and local ranch 

operational and management personnel. There should be no or minimal public use on these 

roads. 

Projected locations of access roads within the EIS analysis area are shown on Figure 4, General 

Layout Map. A typical road cross-section with parallel, buried gas/water gathering and electric 

lines is illustrated as Figure 7, Typical Access Road. 

Seminoe Road Gas Development Project 2-5 
Draft Environmental Impact Statement November 2005

Access roads would be reclaimed as soon as they are no longer needed. However, to satisfy 

possible requests by the BLM or the fee surface owner, an access road may be stabilized and 

allowed to revert to a two-track trail upon completion of the proposed project. Reclamation would 

be completed by the Proponent as set forth in Appendix F, Reclamation Plan. 

2.4.3 Well Pads 

The area physically affected by a typical well pad for drilling operations would be approximately 

2.2 acres. Each well pad must be a level area for placement of the drilling rig and its support 

equipment, along with space for an earthen reserve pit to contain drilling fluids and for topsoil 

material storage. The projected locations of well pads are shown on Figure 4, General Layout 

Map. There would be a minimum setback of 500 feet between the well pad and the high water 

mark of Seminoe Reservoir and the North Platte River. A typical drill pad layout is shown on 

Figure 8, Typical Well Pad Layout During Drilling Activities. 

After drilling is completed and production equipment is installed, the Proponent would implement 

interim reclamation measures for each well pad site, thereby reducing the disturbed area from 2.2 

acres to 1 acre, which is the size needed for production operations. See Appendix F, 

Reclamation Plan. 

Well pad sites would be recontoured to approximate the original topography to blend with 

surrounding terrain. Produced water, gas lines and electric distribution lines would be buried and 

installed at the wellhead. The well pump, separator building, and other production facilities are 

shown on Figure 9, Typical Producing Well Layout. 

2.4.4 Drilling and Production Operations 

Following access road and well pad construction, the components of a rotary drilling rig would be 

transported to the well pad and erected on site. Drilling would be conducted to the desired target 

zone, and appropriate casing would be installed and cemented in place as required by the 

Wyoming Oil and Gas Conservation Commission (WOGCC). Cuttings and drilling fluids would be 

contained in the reserve pit. See Figure 8, Typical Well Pad Layout During Drilling Activities. 

After development drilling, each well would be production tested. The rig used to drill the well 

would be replaced with a smaller surface rig, which would be used to ensure proper perforation of 

the target coals. Well pumping units and other production facilities would be installed to facilitate 

2-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

the pumping activities. Produced water and gas would be separated at each wellhead in a small 

separator building. Following production testing and facility installation, interim reclamation 

activities would be conducted to reduce the well pad site to approximately 1 acre in size. See 

Figure 9, Typical Producing Well Layout. 

2.4.5 Gas and Water Gathering Systems 

Produced natural gas from wells would be transported to one of three centralized compressor 

stations (see Figure 4, General Layout Map) via an underground pipeline gathering system. 

These infield gas-gathering pipelines would normally be located adjacent to and parallel to water 

lines and access roads to minimize disturbance. Infield gas pipelines generally would be 3 to 6 

inches in diameter, and buried to depths of 4 to 6 feet, which would be below expected frost 

zones, and located adjacent to roads. 

Water-gathering lines would be installed within the same trench as the gas-gathering pipelines. 

Water would be piped via 3 to 6 inch diameter pipelines, buried at depths of 4 to 6 feet, which 

would be below expected frost zones, and delivered to appropriate treatment and discharge 

systems. See Section 2.4.8, Produced Water Management. Produced water pipelines would 

typically be located adjacent to roads. 

The Proponent also plans to bury electric distribution lines adjacent to access roads as set forth 

in Section 2.4.10, Power. 

2.4.6 Compressor Stations 

The Seminoe Road Project would eventually require three compressor stations; their general 

locations are shown on Figure 4, General Layout Map, and these sites would be accessed by 

local or resource roads. The three compressor stations would be installed as the gas field is 

developed. Each station would require approximately 10 acres, and a planned layout for a 

compressor station is shown on Figure 10, Compressor Station Layout. Plans for building and 

operating the compressor station in Section 10, T23N, R85W, were discussed in detail in the 

Pipeline Project EA (WY-030-EA2-229); and the BLM has approved this compressor for 

construction and operation. The remaining two compressor sites are likely to be located in 

Section 34, T23N, R85W and Section 23, T22N, R85W, respectively. See Figure 4, General 

Layout Map. The exact locations of the two compressor sites could be shifted to mitigate impacts 

to any sensitive wildlife issues, such as sage grouse leks, or to minimize visual impacts. 

Seminoe Road Gas Development Project 2-7 
Draft Environmental Impact Statement November 2005

Equipment associated with each compressor station would likely include two 1,000 horsepower 

compressors and a single dehydration unit. This equipment would be housed in a metal, sound 

reducing building, painted with a BLM approved color, and have a stack anticipated to be no 

higher than 25 feet. A work building would also be located at each compressor station location. 

The compressor station storage yard would contain a small maintenance building, pipe racks for 

casing, tubing and rods, and fuel storage, as well as additional storage space for pumping units, 

motor separators, miscellaneous valves, fittings, poly pipe, and other equipment. 

A pig launching facility for pipeline maintenance would likely be sited within each compressor 

station storage area. “Pigs” remove condensate liquids from the pipeline by “pigging” the line 

regularly. This activity maintains line efficiency and controls corrosion. 

2.4.7 Gas Gathering Pipeline and Terminal Facilities 

A high-pressure gas gathering pipeline would connect the three compressor stations with an 

interconnect near Walcott, Wyoming. Plans for building and operating the high-pressure gas 

gathering pipeline and terminal interconnect facilities were discussed in detail in the Pipeline 

Project EA (WY-030-EA2-229) and previously approved for construction and operation by the 

BLM. 

The approved pipeline alignment and Walcott interconnect facilities are shown on Figure 4, 

General Layout Map. A pig catcher, separator, dehydrator and associated tanks would be 

constructed at the southern terminus of the high-pressure, gas-gathering pipeline where it joins 

the commercial transmission/sales pipeline. Please refer to the related discussion in the Pipeline 

Project EA (WY-030-EA2-229) for further information; this document is on file at the BLM Rawlins 

Field Office. 

2.4.8 Produced Water Management 

The coals of the western Hanna Basin are water bearing, and the desorption (release) of natural 

gas occurs when the formation’s hydrostatic pressure is reduced by pumping water out of the 

coal formation through a well bore. As hydrostatic pressure drops, the physical bond between the 

coal and the natural gas molecules breaks, the gas diffuses through the coal into the natural 

fractures, and flows with the water stream towards the zone of lower pressure at the well bore. 

Therefore, to create favorable conditions for the release of natural gas from the coal seams, 

2-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

water must be produced prior to and during natural extraction, and water management would be 

a key component of the Seminoe Road Project. 

If the proposed action is selected, an estimated 29 to 44 gallons of water per minute (gpm) (0.06­

0.10 cubic feet per second [cfs] or 1,000 to 1,500 barrels per day) would be pumped (via 

submersible pump) from each well. This expected production range would remain constant for 

each well for at least a year and thereafter is expected to decline at 10 to 15% annually. Actual 

discharge from each borehole might be less, depending on geologic conditions, pumping rates, or 

interference from adjacent wells. Produced water would be discharged to ephemeral drainages at 

various locations in the EIS analysis area. See Figure 12, Produced Water Discharge Points - 

Alternative B. 

Daily water production during the build-out would be expected to increase for the first 4 to 5 years 

of operations, then stabilize at a level of approximately 5,250 gallons of water per minute (12 cfs 

or 180,000 barrels per day). After 9 to 10 years, water production would decline for the remainder 

of the project life because no additional wells are planned. 

A detailed Water Management Plan for the Pilot Project, dated April 2001, is on file with the BLM 

Rawlins Field Office. A schematic of a typical water treatment facility (as is being used for the 

Pilot Project) is illustrated on Figure 11, Water Treatment Facilities Layout. Water produced 

from the Pilot Project wells is regulated under a National Pollutant Discharge Elimination System 

(NPDES) permit (NPDES Permit WYW004-1807) issued from the Wyoming Department of 

Environmental Quality (DEQ). The proposed method for managing produced water as the project 

expands is expected to be similar to that currently employed by the Pilot Project, and this 

assumes that the Wyoming DEQ would continue to require treatment for iron and manganese at 

future discharge points. Under future modifications to the NPDES permit, the Wyoming DEQ 

could change discharge standards, which, in turn, could cause the Proponent to alter or refashion 

water treatment facilities and methods. 

The Proponent currently discharges produced water into Pool Table Draw and uses three 

approved discharge points, pursuant to the aforementioned Pilot Project NPDES permit. At the 

appropriate time during the Seminoe Road Project, the Proponent would seek to modify its 

NPDES permit to allow for up to fifteen additional discharge points. The tentative location of these 

discharge points is shown on Figure 12, Produced Water Discharge Points – Alternative B. 

Seminoe Road Gas Development Project 2-9 
Draft Environmental Impact Statement November 2005

With three exceptions, water released at project discharge points would flow down various 

drainages, which are tributaries of the Seminoe Reservoir or North Platte River. 

The exceptions to release of produced water discharge into drainages would be in the project 

area south of the Seminoe Reservoir, where discharge water would be routed into three closed 

basin playas. From the playas, the water would evaporate and/or infiltrate. 

2.4.9 Beneficial Use of Produced Water 

Water produced at the Seminoe Road Project would have a number of beneficial uses, including 

the production of natural gas. The following beneficial uses are proposed by the Proponent: 

(1)	 Project construction, development and operational activities would use water for drilling 

operations, road dust control, and on-site facilities. Water could also be available for fire 

suppression purposes, whether such a fire would be a structure or rangeland fire. In 

addition, it is expected that Carbon County and other government agencies would 

request and use water for road maintenance activities. 

(2) 	 The Proponent has and would continue to work with the BLM and private landowners to 

place stock watering tanks and/or construct stock ponds throughout the EIS analysis 

area where practical and reasonable. Although most of the EIS analysis area is 

managed for winter livestock grazing, these tanks and ponds, supplied with produced 

water, could assist the private landowners and the grazing permitees with more efficient 

rangeland and grazing management practices. 

(3)	 The Wyoming Water Development Commission (WWDC) and the Wyoming State 

Engineer’s Office, in partnership with the U.S. Bureau of Reclamation initiated 

development of a water conservation program from Wyoming in 1998. The purpose of 

this effort is to develop options for conserving water that targets best water 

conservation practices. One of the major obstacles facing these agencies in the North 

Platte River Basin is the development of a program that would help conserve and 

recover federally listed threatened and endangered species and critical habitat along 

the river that depend on flows in the North Platte River system in the state of Nebraska. 

Recognizing these concerns, the WWDC is proposing that Seminoe Road Project 

2-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

produced water not otherwise used for the beneficial uses discussed above could aid in 

this effort of downstream conservation. 

2.4.10 Power 

The Seminoe Road Project would eventually be completely electrified. However, during the first 

two years of development, the Proponent would temporarily need to use propane, natural gas 

fired or diesel engines or generators at the well sites. These two years are the anticipated 

timeframe for substation construction and installation of buried electric distribution lines. These 

electric distribution lines, occurring between the substation and well sites, would be buried in 

trenches alongside the roads, however, separated from the infield gas lines. In addition, 

throughout the construction and drilling portion of the project, there would probably be a need for 

some propane and natural gas fired or diesel engines or generators at certain “out-lying” well 

sites; these would be replaced with electrification as electric lines are installed (buried) to these 

“out-lying” sites. Appropriate Wyoming DEQ air quality permits would be acquired for all 

combustion equipment. 

Electricity for the Seminoe Road Project would likely come from the existing WAPA 115 kV 

transmission line located within the EIS analysis area, on the west side of County Road 351. A 

high voltage substation would be constructed to accept power from the transmission line. This 

substation would be located at the compressor station site in Section 10, T23N, R85W. See 

Figure 4, General Layout Map. An approximate 8,000-foot long overhead transmission line 

extension would be constructed from the existing line to the substation. This extension line would 

be built using standard industry procedures to prevent raptor electrocution. 

Substations would also be installed at the other two proposed compressor sites. The electric 

distribution lines that feed the other two substations, as well as the electric distribution lines to 

well pad sites, would be buried along access roads in most cases. 

Once power supplies are established, the Proponent would maintain up to five portable propane 

or natural gas fired engines and/or generators on site to serve well pad and compressor 

operations during emergency situations where electric power is disrupted. 

Seminoe Road Gas Development Project 2-11 
Draft Environmental Impact Statement November 2005

2.4.11 Work Force 

The construction and well development phases of the Seminoe Road Project would require a 

workforce of 70 to 90 people. These phases would occur during the first ten years of build-out. 

The Proponent estimates that approximately 50% of this workforce would be hired locally, within 

Carbon County. 

As the project operation phase begins, the Proponent would require a fulltime workforce. This 

workforce would handle day-to-day operations, including routine maintenance. The Proponent 

estimates that a peak operating and maintenance force of approximately 40 to 60 employees and 

contractors would be employed. This workforce would be needed throughout the projected 30­

year life of the project. The Proponent estimates that approximately 80% of this workforce would 

be hired locally within Carbon County. 

Decommissioning and final reclamation activities at the end of project life would require 

approximately 30 to 50 people. The Proponent would manage this work using subcontractors that 

specialize in reclamation activities. The Proponent estimates that approximately 95% of this 

workforce would be hired locally within Carbon County. 

2.5 Direct Discharge of Produced Water Into Seminoe Reservoir 

and North Platte River (Alternative C) 

Alternative C would be similar to Alternative B with two exceptions. First, unlike Alternative B 

where produced water is discharged to ephemeral drainages, produced water from the water 

collection and treatment facilities would be routed for direct discharge into Seminoe Reservoir or 

the North Platte River. Second, in comparison with the electrified scenario presented for 

Alternative B, gas powered down-hole well pumps and compressors would be utilized for 

Alternative C. 

There are a number of possible design and engineering options for routing produced water for 

direct discharge into Seminoe Reservoir or the North Platte River, including buried pipelines, 

surface-laid pipelines, open ditches or canals; it is expected that the selected option would 

parallel the drainages as shown in Figure 14, Direct Discharge Into Seminoe Reservoir – 

Alternative C. 

2-12 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

An estimated 17 miles of water pipelines would be installed from the collection and treatment 

facilities to the discharge locations into Seminoe Reservoir or the North Platte River. See Figure 

14, Direct Discharge into Seminoe Reservoir – Alternative C. These pipelines would be sized 

to accommodate produced water volumes and would probably range from 12 to 18 inches in 

diameter. There would be only limited disturbance if such pipelines are placed on the surface. 

However, if such pipelines are buried below expected frost zones, at depths of 4 to 6 feet, with an 

estimated 50-foot wide disturbance corridor for this pipeline installation, an estimated 103 acres 

would be disturbed. A buried pipeline would also probably be constructed outside the floodplain of 

the drainages to avoid erosion impacts from flash floods to the disturbed pipeline ROW. 

Canals or ditches could be used to convey produced water, but they would be less efficient than 

pipelines as some water would be lost to infiltration and evaporation (similar to Alternative B). 

Canals or ditches, like buried pipelines, would probably be constructed outside the floodplain of 

the drainages, less they become susceptible to erosion impacts from flash floods. In addition, 

canals and ditches must be installed at a relatively constant shallow grade (probably at around 

0.5%) and/or lined with rock rip-rap to avoid channel erosion. They would be constructed to 

essentially parallel natural contours, and this would cause them to be configured in a serpentine 

fashion. This alignment could also create more disturbance than a buried pipeline ROW. In 

addition, aqueduct-like structures would be needed where the canal or ditch crossed over 

drainage channels. 

The produced water is relatively warm temperature (90 to 95° F). Given the coldwater fishery of 

the North Platte River and Seminoe Reservoir, produced water likely would have to be “cooled” to 

a temperature consistent with the receiving water. Although there are numerous possible 

engineering design options for cooling produced water, this alternative considers the use of indrainage ponds (similar to “stock ponds”). See Figure 15, Design Concepts for Direct 

Discharge – Alternative C. Such storage time would allow for produced water to cool to 

ambient temperatures and also allow for possible maintenance time on pond outlet structures, 

pipelines, or the pipeline outlet structures, if necessary. 

In-drainage ponds would be designed and constructed with both a principal and an emergency 

spillway. The principal spillway would allow for discharge of produced water, while the emergency 

spillway would only be necessary in the event of major runoff events. See Figure 15, Design 

Concepts for Direct Discharge – Alternative C. 

Seminoe Road Gas Development Project 2-13 
Draft Environmental Impact Statement November 2005

Based on the design option set forth for this alternative on Figure 14, Direct Discharge into 

Seminoe Reservoir – Alternative C, it is estimated that 16 ponds would be required. Assuming 

2 to 3 acres for each pond, approximately 32 to 48 acres would be affected with the installation of 

these ponds. 

The water pipelines would terminate at the high water mark of Seminoe Reservoir or the North 

Platte River. Outlet structures would be designed and installed with energy dissipaters. See 

Figure 15, Design Concepts for Direct Discharge – Alternative C. 

No permanent all-weather roads would be established parallel to the pipeline. No maintenance 

should be needed for water pipelines; but, if problems develop, crews could access the pipeline 

along the pipeline ROW make necessary repairs. 

At the end of the project, the in-drainage ponds could remain as long-term stock ponds to satisfy 

possible requests by the BLM of the fee surface owner. However, if there is no long-term need 

for such ponds, they would be removed and the areas reclaimed. 

2.6 Underground Injection of Produced Water (Alternative D) 

Underground injection of produced water is an alternative to surface discharge, and this process 

is typically used when the produced water quality is of very poor quality, when there are 

regulatory restrictions on surface discharge, and where the local geology is conducive to such a 

disposal method. 

Underground injection of produced water beneath the Mesaverde coals, the deepest target of the 

Seminoe Road Project, was considered but not evaluated in detail given, impermeable geologic 

formations, coupled with the expected complexity and costs of delivery. The rock strata directly 

beneath the Mesaverde coals are deep and are thought to exist under intense hydrostatic (water) 

pressure, which would make the injection of anticipated volumes of produced water infeasible. 

The review of geologic logs from the Pilot Project drilling revealed a 30 to 40 foot thick sandstone 

layer, identified as the “Dad Sandstone,” found within the 1,000 foot thick Lewis Shale Formation 

that separates the Medicine Bow/Fox Hills and Mesaverde coals (HydroGeo 2003a). Little is 

known about the Dad Sandstone; however, based on existing information and geologic inference, 

this Dad Sandstone is projected to be continuous across the EIS analysis area at a depth of a few 

2-14 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

hundred feet to over 10,000 feet, and have similar geologic characteristics as sandstones found 

in the Fox Hills formation. 

Under Alternative D, produced water would be injected into the Dad Sandstone, and a series of 

water injection facilities would be installed at strategic locations within the EIS analysis area. See 

Figure 16, Underground Injection of Produced Water – Alternative D. 

Preliminary modeling based on general geologic interpretations indicates the Dad Sandstone may 

be able to accommodate the injection of water (HydroGeo 2004); however, additional evaluation 

would be necessary with future drilling into the Dad Sandstone and when the associated data 

(obtained from drilling) are analyzed. For purposes of this EIS, it is assumed that water injection 

facilities would be located at the same locations proposed for water treatment facilities under 

Alternative B, but specific future study of the Dad Sandstone might reveal that additional facilities 

and infrastructure would be required to inject and distribute produced water homogeneously 

throughout the formation. 

Injection facilities would require electric-powered water-injection pumping equipment and 

associated infrastructure (water holding tanks, water storage ponds, enclosed structures for the 

pumps and operational controls, compressors, and storage room for pipes, values and other 

spare parts). Similar to Alternative C, surge water capacity (tanks or water holding ponds) would 

be necessary adjacent to water injection facilities. Water storage would allow for routine or 

emergency maintenance on water injection facilities. Without such storage, well field production 

pumping could be stopped or curtailed. 

It may be necessary to have two or more injection wells at each point of injection to allow for 

efficient and continuous injection. Experience at the existing coalbed natural gas activities at the 

Atlantic Rim Project (southwest of Rawlins) indicates that one injection well would be needed for 

every eight to twelve coalbed wells. At this ratio, the Seminoe Road Project would require 

approximately 100 to 150 water injection wells; however, the Seminoe Road and Atlantic Rim 

projects have different geologies, so the actual number of possible water injection wells for the 

Seminoe Road Project would be determined only when additional data and analyses are 

completed on the Dad Sandstone. It is projected that these Seminoe Road Project injection wells 

would be distributed throughout the EIS analysis area and could be located on existing well pads. 

The other aspects of Alternative D would remain the same as for Alternative B. 

Seminoe Road Gas Development Project 2-15 
Draft Environmental Impact Statement November 2005

2.7 Reclamation Measures 

BLM reclamation policies focus on returning disturbed areas to productive uses consistent with 

land management policies. The purpose of reclamation is to return disturbed areas on both 

private and public land to stabilized and productive conditions that ensure long-term protection of 

land and water resources. 

The Proponent discusses reclamation for the Seminoe Road Project in Appendix A, 

Proponent’s Project Description. The BLM has developed its requirements for reclamation at 

the Seminoe Road Project. See Appendix F, Reclamation Plan. 

The reclamation objectives for the Seminoe Road Project would be as follows: 

3⁄4 Reclaim wildlife habitat; 

3⁄4 Reclaim livestock grazing land; 

3⁄4 Protect water quality; 

3⁄4 Protect public, livestock and wildlife by proper well abandonment; 

3⁄4 Minimize overall disturbance levels by implementing interim reclamation; 

3⁄4 Minimize the establishment and spread of weeds; 

3⁄4 Reclaim areas to pre-project viewshed quality; and, 

3⁄4 Ensure reclamation is consistent with BLM Great Divide RMP. 

The post-project land uses on federal lands would be managed for multiple uses, including 

grazing, wildlife habitat, and dispersed recreation, consistent with the provisions of the RMP. 

2.8 Management, Mitigation and Monitoring Measures 

The Proponent proposes numerous management, mitigation and monitoring measures to 

minimize environmental impacts and to ensure productive multiple uses both during and 

following final project closure and decommissioning. Some of these measures are standard 

practices or the result of BLM or other government agencies regulations and policies. 

The Proponent would incorporate environmental management and mitigation measures into dayto-day operations and use monitoring to establish whether anticipated impacts are realized. 

These measures would be employed with certain refinements evolving from the alternative that 

2-16 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

the BLM selects at the end of this EIS process. In addition, depending on the decision(s) for this 

EIS, BLM may identify additional site-specific management and mitigation measures during the 

APD application processes; this would occur in subsequent site-specific NEPA analysis tiered to 

the ROD for this EIS. The Proponent would also be subject to additional operating requirements, 

including permit limits and conditions, emanating from a variety of other applicable regulations 

administered and enforced by other local, state and federal government agencies. 

2.8.1 Planning and Design 

(1)	 Prior to construction, the Proponent would submit to the BLM an APD for each well 

pad, pipeline segment, and access road, or groupings of such project features, and the 

BLM would conduct site-specific NEPA analysis tiered to the ROD. See Section 2.4.1, 

Planning and Pre-Construction Activities. Well pad locations and the routing of 

associated access roads/pipelines/electric utilities on both public and private lands 

would be selected and designed to minimize disturbance to areas of important wildlife 

habitat, scenic quality, and/or recreational value. 

(2) 	 Following APD submittal, representatives from the Proponent and the BLM would 

conduct an on-site inspection of proposed disturbance sites (e.g., well pads, roads, 

pipelines, electric utility lines, etc.) to finalize site-specific environmental management 

and mitigation measures. 

(3)	 BLM would consult with the Wyoming Game and Fish Department (WGFD), the 

USFWS, the State Historic Preservation Office (SHPO), and other governmental 

agencies, as appropriate or when required. 

2.8.2 Sewage, Trash and Other Waste Material 

(1)	 Portable self-contained chemical toilets would be provided for human waste disposal. 

Upon completion of drilling activities, or as required, toilet holding tanks would be 

pumped and their contents disposed of at an approved sewage facility in accordance 

with applicable rules and regulations regarding sewage treatment and disposal. 

(2)	 Garbage and non-flammable waste materials would be collected in self-contained 

portable dumpsters or trash cages and hauled off site to an approved sanitary landfill. 

Seminoe Road Gas Development Project 2-17 
Draft Environmental Impact Statement November 2005

(3) 	 No trash would be placed in the reserve pit at the well pad locations, nor would any 

open burning of garbage and refuse be allowed on the project area. 

(4) 	 Debris and other waste material not contained in the trash cage or dumpsters would be 

cleaned up, removed from the well sites, and disposed of at state-approved sanitary 

landfill. 

(5)	 No potentially harmful materials or substances would be left on the project site. 

2.8.3 Cultural and Historic Resources 

(1)	 Cultural surveys would be conducted prior to disturbance according to procedures 

outlined in Appendix M, Cultural Resource Management Plan affected by 

construction and operations. 

(2)	 The Proponent and its contractors would inform their employees about relevant federal 

regulations protecting cultural resources. 

(3)	 Any objects of historic or cultural interest discovered during construction and operation 

would be brought to the attention of the responsible BLM official. The Proponent would 

halt construction activities in potentially affected areas in the event that previously 

undetected cultural resource properties are discovered during construction. The BLM 

would consult with the SHPO as necessary. Proper mitigation measures would be 

developed, and construction in the affected area would not resume until authorized. 

2.8.4 Paleontological Resources 

(1)	 Any objects of paleontological interest discovered as a result of construction would be 

brought to the attention of the BLM. Construction activities in the affected area would 

cease until appropriate clearances are issued by the BLM. 

2.8.5 Vegetation 

(1)	 Removal or disturbance of vegetation would be kept to a minimum by using previously 

disturbed areas wherever possible (including existing ROWs) and by limiting the area 

used by equipment/material storage yards and staging areas. 

2-18 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

(2) 	 Disturbed areas would be stabilized and seeded in accordance with BLM approved 

reclamation plan. See Appendix F, Reclamation Plan. 

2.8.6 Weeds 

(1) 	 The Proponent would control weeds along road ROWs, at well sites, and within any 

other areas disturbed by the project or areas infested as a result of weeds in project 

disturbed areas. 

(2) 	 Prompt interim reclamation would be implemented, and native seed mixtures would be 

used for reclamation. See Appendix F, Reclamation Plan. 

(3) 	 Hand pulling/digging, biological control (e.g. goats), mechanical methods, and/or 

application of approved herbicides would be used for control of weeds, as appropriate. 

(4) 	 Only BLM-approved herbicides would be used, and the Proponent must receive BLM 

approval before using such herbicides. 

2.8.7 Road Construction/Transportation 

(1)	 Roads would be constructed specifically to support field development and operations, 

while following BLM guidance and considering private landowner needs. 

(2) 	 Access road location and design would be considered and approved by BLM before 

any ground disturbing activities occur. 

(3)	 Roads would be designed to minimize surface disturbance and surfaced with gravel to 

provide year-round use necessary for project operations. Telemetry and other 

technology would be employed to minimize traffic during periods of wildlife sensitivity. 

Existing roads would be used and upgraded where possible to access the planned drill 

pad sites or help minimize surface disturbance. 

(4) 	 Small and short road loops would be discouraged to minimize surface disturbance and 

vehicle traffic. 

(5) 	 Standard BLM design and construction procedures as outlined in the BLM Manual, 

Section 9113 (Roads), and in the “Gold Book” Oil and Gas Surface Operating 

Seminoe Road Gas Development Project 2-19 
Draft Environmental Impact Statement November 2005

Standards for Oil and Gas Exploration and Development, 3rd Ed. for oil and gas access 

roads would be employed for road development on both public and private land, unless 

other effective and safe design options that cause less surface disturbance are 

approved by BLM. The Proponent and its contractors would comply with existing 

federal, state and county requirements and restrictions with regard to transportation. 

(6)	 Available soil material (up to 12 inches) would be removed from road corridors prior to 

construction activities. This material would be stockpiled for later redistribution on back 

slope areas of the borrow ditch. Borrow ditches would be seeded in the first season 

after initial disturbance. 

(7)	 Roads would be constructed with effective drainage and erosion control structures, 

such as relief culverts, drainage culverts, wing ditches, etc. 

(8) 	 Roads would be built, surfaced, and maintained to be safe. A regular maintenance 

program would include activities such as blading, ditching, re-surfacing, and culvert and 

cattle guard maintenance/replacement, as needed. 

(9)	 Special road designs would be completed when roads are sited in areas of rough 

terrain or high erosion potential, and these roads would be monitored for erosion during 

and after construction. 

(10)	 During drilling and operation, traffic would be restricted to state and county roads, such 

as Carbon County Road 351, and to roads developed for the project. Given 

checkerboard ownership, there would be no new public access to the project area, 

such as to the Seminoe Reservoir and the North Platte River. Access from Carbon 

County Road 351 would be limited to private surface, where gates would be used to 

control public access to the project area. 

(11)	 The Proponent would set and self-enforce speed limits (25 mph) commensurate with 

road type, traffic volume, vehicle types, wildlife stipulations and site-specific conditions, 

as necessary, to ensure safe and efficient traffic flows. As necessary, signs would be 

placed along roads to identify speed limits, travel restrictions, and other standard traffic 

control information. 

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November 2005 Draft Environmental Impact Statement

(12)	 Off-road travel by Proponent and contractor vehicles would be prohibited except in 

emergency situations. 

(13)	 New or improved roads through crucial wildlife habitats would be gated and locked, with 

appropriate cautionary signage, as directed by the BLM to prevent unnecessary access 

and wildlife disturbances. 

(14)	 Following permanent project closure, the Proponent would close and reclaim roads as 

set forth in Appendix F, Reclamation Plan. 

(15)	 The Proponent and its contractors would comply with requirements of the Wyoming 

Department of Transportation and Carbon County for any oversize or over weight 

loads. Special arrangements would be made with the Wyoming Department of 

Transportation and/or Carbon County to transport any oversized loads to the project 

area. 

2.8.8 Chemicals and Hazardous Materials 

(1)	 The Proponent and its contractors would manage chemicals and hazardous materials 

in a manner that complies with applicable federal, state, and local regulations. A list of 

hazardous materials that may be present on site is set forth in Appendix G, 

Hazardous Materials Management Plan. 

(2)	 Releases of hazardous materials would be reported to the BLM and would be handled 

under the Rawlins Field Office “HazMat Release Contingency Plan.” 

(3) 	 The Proponent and its contractors would transport, locate, handle, store and use 

regulated hazardous materials in an appropriate manner that protects workers and the 

public, and prevents accidental releases to the environment. 

(4) 	 The Proponent would develop and use, as necessary, a Spill Prevention Control and 

Countermeasure (SPCC) Plan for the operation as required by the Federal Oil Spill 

Prevention regulation (40 CFR 112) as administered by the Environmental Protection 

Agency (EPA). In the SPCC Plan, the Proponent would identify a spill response 

program that includes overall management objectives, instrumentation and equipment 

needs, response actions, monitoring and reporting requirements, and general safety 

Seminoe Road Gas Development Project 2-21 
Draft Environmental Impact Statement November 2005

considerations for employees, contractors, and the general public. Copies of the SPCC 

plan would be given to appropriate Proponent’s personnel, contractors, and field 

personnel. This plan would also be kept on file at the Proponent’s Denver, Colorado 

office. In addition, the Proponent would develop a Hazard Communication Program and 

Emergency Response Plan and would coordinate with the BLM in the development of 

this plan. See Appendix G, Hazardous Materials Management Plan. 

2.8.9 Air Quality 

(1) 	 The Proponent would meet all applicable state and federal air quality requirements. 

This would mean compliance with applicable Wyoming ambient air quality 

requirements. (WAAQS), National Ambient Air Quality Standards (NAAQS), permit 

requirements (including pre-construction, testing, and operating permits), and other 

applicable regulations, as required by the Wyoming DEQ, Air Quality Division. 

2.8.10 Topography and Physiography 

(1) 	 Areas with high erosion potential and/or rugged topography, such as steep slopes, 

would be avoided where possible. See Figure 17, Steep Slopes, for slopes greater 

than 25% within the EIS analysis area. 

(2) 	 Upon completion of construction and/or production activities, the Proponent would 

restore the topography to blend with surrounding terrain at well site locations, facilities, 

corridors, pipelines, and other facility sites. 

2.8.11 Soils and Erosion Control 

(1) 	 Available topsoil material would be removed during the construction operations to 

achieve reclamation plan objectives. Soil stockpiles would be constructed with the 

lowest profile feasible to reduce the potential for wind erosion, to minimize visual 

impacts, and to diminish the loss of mycorrihizal fungi in the topsoil. Where possible, 

given safety and area considerations, topsoil stockpiles would be oriented to further 

reduce wind erodibility. In addition, soil stockpiles would avoid steep slopes (>25%) 

and would be seeded or otherwise protected to prevent erosion within a year following 

their placement. 

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November 2005 Draft Environmental Impact Statement

(2)	 Considering natural gas production requirements, the location of proposed facilities 

would be sited to avoid or minimize, to the degree possible, disturbance to sensitive 

soils. While it is not possible to avoid sensitive soils entirely given their occurrence over 

the EIS analysis area, a minimization approach would serve to decrease the potential 

for erosion and increase the potential for successful and timely reclamation. Minor 

siting modifications in sensitive soil areas, targeting lesser slope angles or higherquality soils, would result in lesser and more manageable impacts to the soil resource. 

(3) 	 Off-road vehicle travel by Proponent and contractor vehicles would be prohibited except 

in emergency situations. 

(4) 	 The Proponent would minimize project related travel during periods when soils are 

saturated and excess road rutting (e.g., greater than 4 inches) may occur. To reduce 

erosion and soil loss, the Proponent would use, as appropriate, water bars, silt fencing, 

diversion ditches, revegetation or other erosion control techniques. 

(5) 	 The area of disturbance would be kept to the minimum needed for drilling activities and 

subsequent production activities while still providing for safety. Interim reclamation 

practices would be conducted throughout the life of the project. See Appendix F, 

Reclamation Plan. 

(6)	 Cut and fill slopes for well pads and access roads would be designed to prevent soil 

erosion. Disturbed slopes would be reseeded, mulched, or otherwise stabilized to 

minimize erosion within a year following completion of construction. 

(7)	 Topsoil material would be replaced over disturbed surfaces prior to both interim and 

permanent revegetation. Compacted disturbed areas would be “ripped” to alleviate 

compaction prior to topsoil replacement. Mulching would be used after topsoil 

replacement as set forth in Appendix F, Reclamation Plan. 

2.8.12 Water Resources 

(1) 	 The Proponent would adhere to the limits and conditions contained in the NPDES 

permit issued by the Wyoming DEQ. 

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Draft Environmental Impact Statement November 2005

(2)	 The Proponent would avoid well pad, road and compressor site disturbances within 500 

feet of a perennial stream and within 100 feet of intermittent and ephemeral drainages. 

Road crossings of ephemeral, intermittent and perennial streams would be made 

perpendicular to flow direction. 

(3) 	 Well pad disturbances within 500 feet of wetland and riparian areas should be avoided. 

Where wetland and riparian areas are disturbed by linear features such as roads and 

pipelines, the following measures would be employed: 

3⁄4 Construction across riparian areas would occur during dry conditions (i.e., late 

summer, fall, or dry winters); 

3⁄4 BLM-approved plant species would be used to revegetate any disturbed riparian 

areas; and, 

3⁄4 Reclamation would be completed on affected areas in the first appropriate 

season of the first year after completion of construction activities. 

(4) 	 Discharge of water would comply with the applicable rules and regulations of the BLM, 

WOGCC, and Wyoming DEQ. See Appendix D, Agency Jurisdictions (Permits and 

Approvals). 

(5)	 WOGCC casing and cementing criteria for wellbore plugging would be implemented in 

accordance with standard oil field practices to protect subsurface water bearing zones. 

See Figure 18, Conceptual Schematic of Plugged and Abandoned Wellbore. 

(6) 	 Reclamation of reserve pits containing drilling fluids and muds would be completed 

within one year following completion of drilling, unless additional time is allowed by 

BLM. See Appendix F, Reclamation Plan. 

2.8.13 Wetlands, Special Aquatic Sites, and Waters of the U.S. 

(1)	 Wetlands and Other Waters of the U.S. are regulated under Section 404 of the Clean 

Water Act. See Section 3.0, Army Corps of Engineers, in Appendix D, Agency 

Jurisdictions (Permits, and Approvals). The Proponent would avoid these sensitive 

areas, wherever practical. 

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November 2005 Draft Environmental Impact Statement

(2) The Proponent would conduct inventories for jurisdictional wetlands and waters of the 

U.S. ahead of construction and drilling activity. See Section 2.4.1, Planning and PreConstruction Activities. 

(3) 	 Before any wetlands or other special aquatic sites, riparian areas, streams, and 

Wyoming DEQ Section 401 ephemeral/intermittent stream channels are disturbed, the 

Proponent would obtain the necessary Section 404 permits and authorizations. 

2.8.14 Noise and Odor 

(1) 	 The Proponent would muffle and maintain motorized equipment according to 


manufacturer’s specifications.


(2) 	 In construction and operation areas (such as a drill site or compressor station) where 

noise levels exceed limits specified by the U.S. Occupational Safety and Health 

Administration (OSHA), employees and contractors would use proper personnel 

protective equipment. 

2.8.15 Wildlife and Fisheries 

(1) 	 Reserve pits or other project-related impoundments potentially hazardous to wildlife 

would be fenced. As necessary, if there is a water quality problem, reserve pits or other 

project-related impoundments would be netted to prohibit wildlife access and to ensure 

protection of migratory birds and other wildlife. 

(2) 	 The Proponent would notify employees and contractors of applicable wildlife laws and 

the penalties associated with unlawful take and harassment of wildlife. 

(3)	 During the raptor-nesting period, no disturbance would occur during nesting season 

within designated seasonal buffer zones of an identified raptor nest (depending on 

raptor species and line of sight) until the nest is surveyed by a qualified biologist to 

determine nest activity status or unless an exception is granted by BLM. See Table 2­

2, Raptor Nest Protection Dates. If an active raptor nest is identified, the Proponent 

would restrict construction within the designated buffer zone during the critical nesting 

season for that species. 

Seminoe Road Gas Development Project 2-25 
Draft Environmental Impact Statement November 2005

Table 2-2, Raptor Nest Protection Dates


Raptor Seasonal Buffer 

Golden eagle; barn owl; red-tailed hawk; great-horned owl; other 

raptors February 1 – July 15 

Osprey; merlin; sharpshinned hawk; kestrel; prairie falcon; 

northern harrier; Swainson’s hawk; Cooper’s hawk April 1 – July 31 

Short-eared owl; long-eared owl; ferruginous hawk; screech owl March 1 – July 31 

Burrowing owl April 15 – September 15 

Goshawk April 1 – August 31 

Notes: 

1. Seasonal buffers are for 3⁄4-mile radius for all active raptor nests except for active nests of bald 

eagles, golden eagles, and ferruginous hawks where a 1- mile radius is recommended. 

2. These seasonal buffers have been established as a result of BLM coordination and interaction 

between the WGFD and the USFWS. 

(4)	 Known occupied sage grouse leks would be avoided, and road and well pad 

construction activities within adjacent (2-mile radius from lek) public land areas would 

be avoided during the breeding and nesting season (March 1 – June 30). No 

construction or drilling activities would occur within a 0.25-mile (1,320 foot) perimeter of 

known occupied sage grouse lek sites. Playa lakes would not be inundated by projectproduced water within a 0.25-mile (1,320 foot) perimeter of known occupied sage 

grouse lek sites. The Proponent would conform and comply with current BLM sage 

grouse policy for avoidance, in coordination and cooperation with sage grouse policies 

of Wyoming Game and Fish Department. 

(5) 	 The Proponent would avoid construction activities in crucial big game (mule deer and 

antelope) habitat between November 15 and April 30, unless the Proponent requests 

and the BLM grants a site-specific exception for a portion of this time frame. 

2.8.16 Threatened, Endangered, Proposed, Candidate and Sensitive 

Species 

(1) 	 The Proponent would conduct site-specific analysis for each individual APD for 

compliance with the Endangered Species Act. Given the changing nature of USFWS 

species listings, accepted mitigations and timing stipulations, each APD would be 

assessed and must comply with the standards in existence at the time the APD is filed. 

(2)	 Similarly, the Proponent would implement any BLM requirements concerning BLM 

sensitive species. 

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November 2005 Draft Environmental Impact Statement

2.8.17 Livestock/Grazing Management 

(1) 	 The Proponent would coordinate project activities with ranching operations and BLM 

rangeland management specialist(s) to minimize conflicts with livestock movement or 

other ranch operations. The Proponent would maintain fences, cattle guards, and other 

existing livestock related structures. In areas of high livestock use, the Proponent would 

fence reclaimed areas, as necessary, to ensure successful revegetation. 

2.8.18 Socioeconomics 

(1)	 The Proponent would implement hiring practices that encourage the use of local 

contractors and workers, and would only go outside the region to hire if an adequate 

local pool of candidates cannot be generated. 

2.8.19 Land Use 

(1) 	 The Proponent would minimize disturbance by maintaining as compact an operation as 

possible. See Section 2.8.5, Vegetation; Section 2.8.7 Road Construction and 

Transportation; and Appendix F, Reclamation Plan. 

(2) 	 Roads, power lines, and pipelines would be located adjacent to existing compatible 

linear facilities where practical. 

2.8.20 Recreation 

(1) 	 Generally, access to public land is open. Under conditions of checkerboard land 

ownership, public access is typically constrained by the private landowners. The 

Proponent would work with BLM, state and private landowners to ensure public access 

is consistent with BLM policies. 

2.8.21 Visual Resources 

(1)	 Seminoe Road Project surface facilities would be designed to reduce direct visual 

impacts to visitors using the North Platte River, Seminoe Reservoir, and County Road 

351, which the BLM has designated as a Back Country Byway. The Proponent would 

conform to standards for applicable BLM VRM requirements. 

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Draft Environmental Impact Statement November 2005

(2) 	 The Proponent would minimize road access into the EIS analysis area from Carbon 

County Road 351. Access points would likely be located on private land and gated to 

control public access. 

(3) 	 External lighting would be kept to the minimum required for safety and security 


purposes. 


(4) 	 Facilities would be painted a flat, to blend with the surrounding landscape. Exceptions 

would be allowed for facilities requiring safety coloration by OSHA requirements. 

(5) 	 Reclamation seed mixes would be selected so that revegetated areas would blend into 

surrounding undisturbed vegetation. See Appendix F, Reclamation Plan. 

2.8.22 Health and Safety 

(1) 	 The Proponent considers worker safety as the highest priority of Seminoe Road Project 

construction and operation. 

(2) 	 Well and pipeline installations would meet reliability and safety standards set by 

federal, state and local government agencies. Adherence to such standards would 

minimize or prevent hazards to the Proponent’s employees, contractors, and the public 

and ensure a high level of system reliability. 

(3) 	 The Proponent would set and self-enforce speed limits (25 mph) commensurate with 

road type, traffic volume, wildlife stipulations, and site-specific conditions. Special care 

would be needed by Proponent employees and contractors near where project roads 

intersect Country Road 351 to avoid conflicts or accidents with recreational drivers on 

this county road. 

2.9 Environmental Monitoring Measures 

The Proponent would implement and maintain environmental monitoring programs that meet the 

requirements of the BLM and other agencies as part of the project. Monitoring would determine 

the effects of the development and operations, as well as the effectiveness of the environmental 

management and mitigation measures. Monitoring would also provide valuable input to 

government agencies regarding project performance. The information acquired by monitoring 

2-28 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

would be used as the basis for additional mitigation measures, if necessary, and be considered 

by BLM when reviewing site-specific NEPA documents. 

The Proponent, the BLM and other agencies would develop specific monitoring plans prior to 

project approval or permit issuance, and these plans would become part of the operational plan. 

General monitoring measures are discussed in the following sections. 

2.9.1 Air Quality 

Given the results of the detailed air quality modeling work (see Section 4.1, Air Quality, and 

Appendix H, Air Quality Information), no site-specific air quality monitoring is planned for the 

Seminoe Road Project. The Wyoming DEQ would require the Proponent to obtain air quality 

permits to construct and operate the project. See Appendix D, Agency Jurisdictions (Permits 

and Approvals). The BLM is currently assessing the possibility of statewide air quality 

monitoring, but any plans for such monitoring have yet to be finalized. 

2.9.2 Water Resources Monitoring 

The Proponent would establish or maintain water monitoring throughout project life to assess: 

3⁄4 Compliance with state and federal permits; 

3⁄4 Operational performance; 

3⁄4 Changes in water quality; 

3⁄4 Permanent closure and final reclamation success; and, 

3⁄4 Magnitude and extent of unanticipated releases of regulated substances. 

The Wyoming DEQ would regulate the discharge of produced water under the provisions of a 

NPDES permit (see Appendix D, Agency Jurisdictions (Permits and Approvals). The 

discharge of produced water from the Pilot Project is currently regulated under NPDES Permit 

WYW004-1807. For produced water discharge contemplated under Alternatives B and C, the 

NPDES monitoring program likely would include water quality and flows at the discharge points, 

as is the case for the current NPDES permit for the Pilot Project. Some examples of key 

parameters include pH, conductivity (measure of salinity), sodium, calcium, magnesium, and iron. 

For the underground injection program set forth in Alternative D, the WOGCC would monitor this 

process under the provisions of an underground injection permit. 

Seminoe Road Gas Development Project 2-29 
Draft Environmental Impact Statement November 2005

For an approved action alternative, the Proponent would update the project’s water management 

plan. This plan includes the location of monitoring stations (surface water points, springs and 

seeps), the frequency of monitoring, the parameters for field and laboratory analysis, and quality 

assurance and quality control plans. 

2.9.3 Wildlife Monitoring 

The proposed wildlife monitoring procedures for the Seminoe Road Project are set forth in 

Appendix K, Wildlife Monitoring and Protection Plan. 

2.9.4 Reclamation Monitoring 

The Proponent would monitor for reclamation success according the plans that are approved by 

the BLM. See Appendix F, Reclamation Plan. Areas to be monitored would include soil 

placement, revegetation success, presence of soil erosion, etc. Inspections would be conducted 

by the BLM to verify reclamation success criteria. 

2.9.5 Weed Monitoring 

Because weeds occur and can invade into disturbed and newly reclaimed areas, the Proponent 

would monitor disturbed and reclamation sites for weeds and would implement weed control 

measures to control weeds during operations and until reclamation success criteria have been 

successfully met. See Appendix F, Reclamation Plan. 

2.9.6 Reporting to Regulatory Authorities 

The Proponent would comply with the reporting requirements of the federal, state and local 

government authorities. Such reporting would occur on forms provided or in a report format 

approved by those agencies. Likewise, the timing of reporting would correspond to the 

stipulations set forth in various permit and plan approvals. 

2.10 Alternatives Considered but Eliminated From Detailed 

Evaluation 

Many of the considered alternatives were eliminated from detailed study in this EIS based on 

technical, environmental, legal and regulatory constraints. Following are summaries of those 

alternatives, along with the reasons for eliminating them from detailed consideration. 

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November 2005 Draft Environmental Impact Statement

2.10.1 Mandated Directional or Horizontal Drilling 

Directional and horizontal drilling are two related yet distinct drilling techniques, and they are the 

source of great interest for many people from both inside and outside the drilling industry. 

Directional drilling is used to guide a well to a predefined target. Horizontal drilling is a process of 

guiding a well to a predefined rock strata (like a coal seam), then realigning the well to track 

within or parallel to the strata. 

The BLM and the Proponent recognize that directional and horizontal drilling techniques are tools 

to be used when unacceptable surface effects would occur, and they have the option to utilize 

these techniques as necessary based on site-specific issues and conditions. However, mandating 

directional or horizontal drilling for every well is not a practical alternative for the Seminoe Road 

Project based in part on the nature and arrangement of the coal formations. Instead, the BLM and 

the Proponent can manage environmental impacts with careful planning, using site data to realign 

roads and shift well pad sites, and implementing environmental management and mitigation 

measures and proper interim and final reclamation techniques. 

2.10.2 Tighter Well Pad Spacing 

As set forth in Section 2.4, Alternative B – Proposed Action, the Proponent plans to space well 

pads every 160 acres. This spacing is determined by the results from the Pilot Project, which 

analyzed many factors including geology, permeability of the target coal seams, and economics. 

One of the important goals of the Proponent is to maximize the natural gas production while 

minimizing surface disturbance and capital and operating expenses. 

The WOGCC regulates well spacing for oil and gas projects. See Appendix D, Agency 

Jurisdictions (Permits and Approvals). This agency strives to ensure maximum recovery of oil 

and gas reserves. That is one of the reasons that coalbed natural gas wells are generally spaced 

evenly within land sections; such spacing allows for uniform recovery of the gas resource. If wells 

are spread too far apart, portions of the gas can be left un-recovered. 

Many coalbed natural gas projects have tighter spacing than one well pad per 160 acres 

proposed for the Seminoe Project. For example, the Powder River Basin in northeastern 

Wyoming has well spacings of 80, 40 and even 20 acres. The tighter well spacing in this region is 

dictated by the coal seam permeability and the general geology, where the coal seams are 

Seminoe Road Gas Development Project 2-31 
Draft Environmental Impact Statement November 2005

thicker and shallower, with relatively flat dips, as compared to the target coals of the Seminoe 

Project. 

The impacts of tighter well spacing were not analyzed for the Seminoe Road Project. This 

alternative was considered but not analyzed given the current reasonable expectation from Pilot 

Project results that the gas resources would be recovered by the wells at a spacing of one per 

160 acres. If it is determined in the future that tighter spacing would be necessary, environmental 

and NEPA analysis would be required to assess additional impacts. 

2.10.3 On-site Centralized Power 

Large on-site generators could be installed to provide permanent electric power to drive the onsite compressors, as well as power the pumps at each well site. Similar to electric power 

distribution in Alternative B, Proposed Action (see Section 2.4.9, Power), electric power would be 

distributed to individual well pad sites from the centralized compressor areas via buried electric 

utility lines. 

The turbine generators would be run on either diesel or methane/propane. Initially, diesel fuel 

would probably be transported to the Seminoe Road Project to operate the on-site generators. 

However, once gas is produced at the site, the turbine generators would then be reconfigured to 

operate on natural gas. 

The use of large on-site generators for permanent project-wide electric power would require 

additional operational and maintenance staff. Their use could also result in elevated noise levels 

(both from operation of generators and increased traffic from fuel transport and extra staff), 

increased air emissions (again from operator of generators [gaseous] and traffic [gaseous and 

particulates]), increased visual impacts to Back Country Byway travelers, and extra traffic on 

Carbon County Road 351 (fuel shipments and employees). Additional traffic would increase the 

potential for wildlife collisions and possible accidents involving fuel spills. For these reasons, the 

use of on-site generators for permanent project-wide electric power was eliminated from detailed 

consideration in the EIS. The assessment of any environmental conflicts from the use of WAPA 

electricity was considered to be outside the scope of this EIS. 

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November 2005 Draft Environmental Impact Statement

2.10.4 Individual Well Site Power Generation 

Pumps at the Seminoe Road Pilot Project are currently powered by individual, propane-fueled 

motors. This system provided the start-up power needed for the Pilot Project and required no 

installation of electric utility lines. So far, this system has sufficed for Pilot Project operations. 

Under this scenario, propane fuel must be regularly transported to each well site, and the 

individual well site motors require prudent and routine monitoring and maintenance activities. 

If this system were employed for the build-out, it would require over 1,200 individual motors/ 

generators to be located on the project site. Each motor would create gaseous emissions, as well 

as require regular maintenance and fueling. Although produced natural gas could be used to run 

these motors, initial start-up would require fuel to be delivered from a remote source. At the scale 

proposed for development, and given the increased impacts expected under such a proposal, 

electrification resolves most, if not all, resource conflicts in this context and makes further 

consideration of permanent, individual well site power generation needless. 

Given the logistics, operating and maintenance requirements, and possible air quality effects, this 

alternative was eliminated from detailed consideration in the EIS. However, it should be noted 

that the proposed action does allow for some small number of on-site power generation. See 

Section 2.4.9, Power. 

2.10.5 Alternative Energy Sources 

In lieu of fossil fuel electric energy, such as that generated by the Jim Bridger coal-fired power 

plant near Rock Springs, Wyoming, or hydro-electric energy such as produced at the Seminoe 

and Kortes hydroelectric power stations on the North Platte River, wind and solar power sources 

were considered for the Seminoe Road Project, but their use was eliminated from detailed 

evaluation in this EIS. Use of these sources would still require a stable full-time back-up energy 

source, such as electrification. Addition of these energy generation systems, while providing extra 

energy to the grid, would not resolve environmental effects; rather, they would increase effects to 

the environment, primarily due to surface disturbance. 

Both wind and solar power require many acres of land and are visually obstructive. Wind turbo 

blades are noisy, and they can kill birds and disturb livestock. Wind towers, like power line 

structures, can also affect ground-nesting birds such as sage grouse. In addition, both wind and 

solar power can only provide intermittent supplies, which would be unacceptable to the Seminoe 

Seminoe Road Gas Development Project 2-33 
Draft Environmental Impact Statement November 2005

Road Project where constant power would be required to supply compressors and well site 

pumps. 

2.10.6 Overhead Electric Distribution Lines 

Electric distribution lines generally transmit electric loads of 13 kV or less; these would be the 

type of lines needed to supply power to the individual well pads, the compressor facilities and 

miscellaneous operational and maintenance facilities. 

Electric distribution lines should be distinguished from electric transmission lines, which carry 

higher voltage (>13 kV). As an example, the existing WAPA 115 kV line would be considered a 

“transmission” line, as would the proposed line transmitting electricity from the WAPA line to the 

proposed Seminoe Road Project substation. 

Electric transmission lines are rarely buried given the problems of electrically insulating each 

phase and dissipating the heat generated by the conductors. Underground transmission lines 

require three-phase conductors to be encased separately in sealed piping systems with 

constantly circulating oil or nitrogen for cooling. These pipes must be placed in thermal backfill to 

transfer heat. Underground transmission lines are difficult to maintain, and, if problems occur, 

power outages of several days or even weeks might be needed to locate and repair the system. 

Overhead electric distribution lines could be installed to transmit electric power from either a 

substation or an on-site generator to each individual well pad. Overhead lines would require 

wooden or metal power pole structures. Although overhead electric distribution lines and 

associated structures can be easily constructed, they are visually obstructive and can create 

problems for wildlife, particularly electrocution of raptors and reduction or elimination of breeding 

activities for sage grouse. The electric distribution lines could be constructed with a raptor proof 

insulation, to prevent electrocution of raptors; however, the power structures (poles) would 

provide convenient perches for raptors. Not only the presence of raptors on the poles but also 

merely the presence of aboveground structures could affect ground-nesting birds such as sage 

grouse. 

Given visual effects and possible impacts to wildlife, along with the Proponent’s preference for 

burying electric distribution lines, the construction of overhead electric distribution lines was 

considered but eliminated from detailed evaluation in the EIS. 

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November 2005 Draft Environmental Impact Statement

2.10.7 Alternative Water Handling Systems 

Handling and disposal of natural gas produced water are major and essential aspects of the 

Seminoe Road Project. As part of BLM deliberations, the relative merits of the following water 

handling alternatives were discussed: 

3⁄4 Surface discharge to drainages (Alternative B - Proposed Action); 

3⁄4 Surface discharge directly to Seminoe Reservoir and North Platte River (Alternative C); 

3⁄4 Underground injection (Alternative D); 

3⁄4 Irrigation; 

3⁄4 Evaporation; 

3⁄4 Piping to local municipalities and/or industries; and, 

3⁄4 Misting towers. 

Alternatives considered in detail in the EIS are surface discharge to drainages (Alternative B), 

surface discharge directly to Seminoe Reservoir and North Platte River (Alternative C), and 

underground water injection (Alternative D). 

The remaining water handling systems were considered but eliminated from detailed evaluation 

within the EIS. The reasons for this elimination are described in the following sections. 

2.10.7.1 Irrigation 

No irrigation has ever occurred in the EIS analysis area, and irrigation will not be carried forward 

for detailed evaluation in this EIS. Irrigation would result in changes to the native environment, 

modifying or eliminating vegetation communities currently present, and is not consistent with land 

management planning in the RMP or the purpose and need for the Seminoe Road Project. 

Irrigation would also be considered outside the scope of this EIS as no specific proposal for 

irrigation has been submitted from private landowners or mineral lessees. If such a proposal 

should come forward in the future, a separate environmental and NEPA analysis would be 

required to address the specific proposal and to assess impacts. 

Although irrigation may be technically feasible with natural gas produced water, the Wyoming 

BLM presently does not allow irrigation on public lands. In addition, none of the private 

landowners within the EIS analysis area want to invest in the type of irrigation system and 

Seminoe Road Gas Development Project 2-35 
Draft Environmental Impact Statement November 2005

associated management infrastructure required to ensure productive long-term irrigation. 

Furthermore, the area’s soil chemistry is not conducive to irrigation. Soil amendments requiring 

significant and costly land management techniques and resources would be needed to ensure 

long-term soil productivity. In addition, natural gas produced water chemistry must also be 

regularly analyzed and a water-conditioning facility would probably be required to regulate sodium 

adsorption ratio (SAR) levels in the irrigation water. 

2.10.7.2 Evaporation and/or Percolation Ponds 

Evaporating natural gas produced water as the sole means of water handling at the Seminoe 

Road Project was considered but eliminated from detailed evaluation. 

Evaporation ponds would require an extensive expanse of area and cause large scale effects to 

vegetation, which would be inconsistent with land management planning in the RMP. Shallow 

ponds (5 to 10 feet deep), encompassing an estimated area of 3,000 to 4,000 acres, would be 

needed to provide sufficient surface area to evaporate the large quantity of natural gas project 

produced water. In addition, the ponds may need to cover even larger areas to have ample 

volume to account for limited evaporation during freezing conditions. Further, the ponds would 

probably require an elaborate and expensive spray system to further assist the evaporation 

process. Water quality in the constructed evaporation and/or percolation ponds could deteriorate 

over time due to evapo-concentration of salts. Use of large-scale evaporation and/or percolation 

ponds would cause more effects (land disturbance, construction noise and air quality impacts, 

elevated traffic, reduction in grazing area for livestock and habitat for wildlife, visual impacts, etc.) 

than the analyzed alternatives and does not address unresolved resource conflicts from other 

alternatives. 

However, although evaporation as sole means of natural gas produced water is not practical, nor 

feasible, there is the possibility of using the natural playas south of the Seminoe Reservoir for 

some limited evaporation. The Proponent is requesting the use of the natural playas to store and 

evaporate produced water. This system would be combined with a discharge program as outlined 

in Section 2.4, Proposed Action (Alternative B). 

2.10.7.3 Piping Water to Municipalities and/or Industries 

Because the produced water at the Seminoe Road Project is expected to meet drinking water 

standards, the Proponent approached several municipalities in close proximity to the project area 

2-36 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

and the Sinclair Oil Refinery about using water from the project, but the Proponent found no 

interest at this time. It was thought that the towns of Sinclair, Rawlins and/or Hanna might put this 

water to beneficial use to supplement their present water supply. 

Under this alternative, a pipeline infrastructure would need to be developed to supply water to 

these municipalities and the refinery, and modifications would be necessary to the existing water 

treatment facilities. The availability of water for municipality or industrial purposes would be tied to 

the Seminoe Road Project, which in turn would be subject to technical, regulatory, and 

economical conditions that could cause fluctuation in water availability. Because of this, and the 

availability of other water sources, the use of produced water from the Seminoe Road Project 

gives uncertainty to municipalities and industry; therefore, little interest was shown by these 

entities at the time they were approached by the Proponent. 

Given the need for an expensive pipeline infrastructure, existing water plant modifications, the 

uncertainty of supply, and the lack of interest, this alternative was eliminated from further 

consideration. 

2.10.7.4 Misting Towers 

Produced water could be evaporated at the wellhead using misting towers. Misting towers are 

essentially vertical pipes, up to 30 feet in height, with a spray head at the top. At the spray head, 

nozzles produce a fine water mist, which would be adjusted to evaporate the water before it 

reaches the ground. 

Each individual well would require an infrastructure of these towers, spaced far enough apart so 

that the water would not saturate the soil; however, salt would probably still be deposited on the 

soil and could create salt loading problems that could change vegetation species composition. 

Misting towers work best on hot and dry days, and lose effectiveness at night and during winter 

conditions. As a result, misting towers can only be used in combination with another water 

handling technique. 

Misting towers require many acres of land, can be visually obstructive, may create surface 

crusting and sealing of soil beneath the towers, given elevated salinity in produced water require 

a backup system of water handling, and often operate with less than total efficiency and 

effectiveness. For these reasons, their use has been eliminated from detailed consideration in 

this EIS. 

Seminoe Road Gas Development Project 2-37 
Draft Environmental Impact Statement November 2005

2.10.8 Alternative Water Treatment Methods 

Discharge of coalbed natural gas produced water in Wyoming is regulated by the Wyoming DEQ, 

Water Quality Division, under provisions of an NPDES permit. Although the produced water at the 

Seminoe Road Pilot Project meets NPDES discharge standards and requires little, if any, 

treatment, the Proponent has installed and has the ability to use an aeration and filtration system, 

when necessary at two of it’s current NPDES discharge points. See Section 2.4.8, Produced 

Water Management, and Appendix A, Proponent’s Project Description. 

Existing water quality data for the Seminoe Road Project indicate that parameters of interest are 

primarily dissolved iron and manganese. Any qualitative comparison of available water treatment 

processes for produced water must be based on the specific characteristics of the water to be 

treated and the effluent criteria to be achieved. Removal effectiveness, energy and chemical 

requirements, by-products treatment and residual disposal requirements, operational simplicity, 

and system reliability must be assessed as part of any water treatment system screening criteria. 

Water treatment processes not evaluated in detail and eliminated from consideration are shown 

on Table 2-2, Alternative Water Treatment Methods. In addition, a number of proprietary or 

experimental processes have been reported for water treatment but are likewise not addressed in 

the EIS. 

Given expected water quality, none of the processes included in Table 2-3, Alternate Water 

Treatment Methods, are currently expected to be needed for water treatment at the Seminoe 

Road Project. Water treatment, when and if used, must ensure compliance with NPDES permit 

requirements. 

2.10.9 Sole Use of Existing Roads 

Although approximately 300 miles of existing roads currently exist within the EIS 

analysis area, nearly 100 miles of these roads are not in the proper position to access 

the proposed well pad sites or of high enough quality to carry project related traffic. To 

achieve the desired 160-acre spacing for development, an estimated 250 miles of new roads 

must be constructed. In addition, most of the existing roads that can be used (~200 miles) in the 

2-38 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Table 2-3, Alternate Water Treatment Methods


Process General 

Effectiveness 

Comparative Cost 

(capital + operating 

& maintenance) 

Advantages Disadvantages 

Ion Exchange Excellent Moderate - High Selective metal 

treatment possible 

Regenerate 

disposal, possible 

reactive material 

Reverse Osmosis Excellent Moderate - High Effectively removes 

most metals 

Brine disposal, low 

membrane life 

Nanofiltration Good Moderate - High Easier to operate than 

reverse osmosis 

Brine disposal, low 

membrane life 

Electrodialysis Excellent Moderate - High 

Membrane life 

improvement over 

reverse osmosis and 

nanofiltration 

Brine disposal, 

possible reactive 

material 

Granular Activated 

Carbon Good Moderate - High Low technology, lower 

removal effectiveness 

Limited 

effectiveness; need 

to replace carbon 

on frequent basis 

Evaporation / 

Distillation / 

Crystallization 

Excellent High - Very High Very effective, zero 

discharge 

Difficult operation, 

very costly, not 

proven on larger 

scale, brine 

disposal 

Electrolytic Varies Very High Stabilizes available 

metals 

Limited 

effectiveness, metal 

specific, high 

energy cost 

EIS analysis area are two-track roads that do not provide all-weather access. Therefore, even 

though the existing footprint of these roads is used, they would be upgraded to an all-weather 

condition so that personnel and equipment could access well pad sites on a year-round basis. 

Given the impracticality of using only existing roads, and using those roads in their present state, 

this alternative was eliminated from further consideration. 

2.11 Comparison of Alternatives 

Environmental impacts of each alternative are addressed in Chapter 4, Environmental Analysis. 

Table 2-4, Summary of Impacts by Alternative for Each Issue, compares alternatives to the 

issues identified in Chapter 1, Purpose of and Need for Action. 

Seminoe Road Gas Development Project 2-39 
Draft Environmental Impact Statement November 2005

1 Table 2-4, Summary of Impacts by Alternative for Each Issue

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Air Quality 

Fugitive dust 

emissions 

PM10 

PM2.5 

Pilot Project 

permitted with 

Wyoming DEQ Air 

Quality Division; 

impacts much less 

than Alternative B. 

515 tons/year 

120 tons/year 

Same as Alternative 

B 

Same as Alternative 

B 

Gaseous 

emissions 

NO(x) 

SO2 

VOC 

Pilot Project 

permitted by 

Wyoming DEQ Air 

Quality Division; 

impacts much less 

than Alternative B 

320 tons/year 

42 tons/year 

30 tons/year 

1,420 tons/year 

42 tons/year 

1,130 tons/year 

Same as Alternative 

B 

Visibility effects to 

Class I air sheds 

(Wilderness 

Areas) by 

Seminoe Road 

Project 

None expected Unlikely; below 0.5 

deciview (dv) level 

Similar to Alternative 

B 

Same as Alternative 

B 

Cumulative 

visibility impacts 

from all regional 

sources including 

both Atlantic Rim 

and Seminoe 

Road Projects 

None expected 

1 to 4 days per year 

visibility impacts 

greater than 1.0 dv 

threshold for Bridger 

& Popo Agie 

Wilderness Areas in 

western Wyoming. 

Similar to Alternative 

B 

Same as Alternative 

B 

Cultural Resources 

Impacts to cultural 

and historic sites 

None impacted: Pilot 

Project cleared by 

BLM and SHPO 

16% of EIS analysis 

area has been 

previously surveyed 

with results showing 

approximately 1 site 

per 80 acres. Based 

on this ratio, it could 

be projected that 

1,700 sites could be 

identified in entire EIS 

analysis area, but 

with less than 5% 

direct disturbance, 

avoidance of sites 

highly likely. 

Same as Alternative 

B 

Same as Alternative 

B 

Hydrology (Surface and Ground Water) 

Alterations to 

downstream flow 

rates 

Produced water from 

Pilot Project being 

discharged directly 

into Pool Table Draw 

and tributaries. 

A maximum 

discharge rate of 35.5 

acre-feet of water per 

day (1,430 gpm) 

would be added to the 

hydrologic system. 

This represents 

approximately 5% of 

the average January 

low flow and 0.4% of 

the average June 

high flow of the North 

Platte River into the 

Seminoe Reservoir. 

Discharging produced 

Same as Alternative 

B with no infiltration 

losses in ephemeral 

drainages as 

produced water 

discharged through 

pipelines directly into 

Seminoe Reservoir. 

Beneficial use of 

produced water for 

downstream use. 

None of the produced 

water would be added 

to downstream flow 

rates; produced water 

would be injected into 

underground 

formation (Dad 

Sandstone). 

No beneficial use of 

produced water for 

downstream use. 

2-40 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

water into EIS 

analysis area 

drainages would 

result in an infiltration 

loss of an estimated 

2.9 gallons of water 

per foot of drainage 

length per day of flow. 

Beneficial use of 

produced water for 

downstream use. 

Head cutting has 

occurred in Pool 

Erosion of 

ephemeral 

channels 

Table Draw both 

above and below the 

high water mark of 

Seminoe Reservoir. 

Mitigation measures 

are underway above 

the high water mark 

of Seminoe 

Reservoir. Peak 

runoff in drainages 

increased slightly 

due to project-related 

surface disturbances 

Discharge of 

produced water to 

ephemeral drainages 

would cause further 

erosion in drainage 

channels. Peak runoff 

in drainages 

increased slightly due 

to project-related 

surface disturbances 

in the watersheds. 

No additional erosion 

as produced water 

piped to Seminoe 

Reservoir or North 

Platte River. Peak 

runoff in drainages 

increased slightly due 

to project-related 

surface disturbances 

in the watersheds. 

No additional erosion 

as produced water 

injected into 

underground 

formation (Dad 

Sandstone). Peak 

runoff in drainages 

increased slightly due 

to project-related 

surface disturbances 

in the watersheds. 

in the watersheds. 

Sodium levels could 

Impacts to water 

chemistry in 

Seminoe 

Reservoir from 

produced water 

No water chemistry 

changes have been 

noted for Seminoe 

Reservoir as a result 

of Pilot Project. 

increase from 42 mg/l 

to 48 mg/l in Seminoe 

Reservoir during low 

flow month of January 

and if drought 

conditions recur. 

During high flows, 

natural dilution and 

mixing effects would 

essentially eliminate 

Similar but the 

potential to be slightly 

higher than 

Alternative B as 

produced water 

discharged directly 

into Seminoe 

Reservoir via 

pipelines. 

None; water would be 

injected into 

underground 

formation (Dad 

Sandstone) 

any adverse effects. 

Land Use 

Total area 

disturbed by initial 

construction and 

drilling activities 

146 acres (1.8% of 

8,320 acre Pilot 

Project area) 

6,174 acres (4.5% of 

137,000 acre EIS 

analysis area) 

Similar to Alternative 

B 

Similar to Alternative 

B 

Total operational 

disturbance area 

following interim 

reclamation 

69 acres (0.8% of 

8,320 acre Pilot 

Project area) 

2,349 acres (1.7% of 

EIS analysis area) 

Similar to Alternative 

B 

Similar to Alternative 

B 

activities 

Initial land 

disturbance by 

ownership 

BLM 

Private 

State 

73 acres 

73 acres 

0 acres 

3,014 acres 

3,014 acres 

144 acres 

Similar to Alternative 

B 

Similar to Alternative 

B 

Seminoe Road Gas Development Project 2-41 
Draft Environmental Impact Statement November 2005

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Changes in future 

land use 

None; after 

completion of Pilot 

Project, the disturbed 

area reclaimed to 

pre-disturbance land 

use as rangeland. 

None: after 30-year 

project life, the 

operational disturbed 

areas would be 

reclaimed as 

rangeland for 

livestock grazing and 

wildlife habitat. 

Same as Alternative 

B 

Same as Alternative 

B 

Noise 

Construction and 

drilling noise 

effects 

Construction and 

drilling completed. 

Average construction 

and drilling noise 

estimated at 85 dBA 

at 50 feet 

Same as Alternative 

B 

Same as Alternative 

B 

Operational noise 

effects from 

surface facilities 

Individual motors and 

generators provide 

power to well pumps 

at Pilot Project and 

they operate 24 

hours per day, 

creating 70 to 80 

dBA at 50 feet. 

Electrified option; 

negligible noise at 

well sites; electric 

compressor noise at 

50 to 60 dBA at 50 

feet; if enclosed, 

noise levels are 

negligible. 

Non-electric 

alternative: gas 

powered compressor 

noise estimated at 80 

to 90 dBA at 50 feet; 

if in enclosed 

structure, noise 

estimated at 55 to 65 

dBA at 50 feet from 

structure. 

Same as Alternative 

B 

Weeds 

Spread of weeds 

Weed infestation has 

occurred at some 

disturbed sites at 

Pilot Project. 

Potential for weed 

infestations in some 

disturbed sites is high 

to very high. 

Similar as Alternative 

B 

Same as Alternative 

B 

Public and Worker Health and Safety 

Potential 

possibility of 

accident that 

would necessitate 

an emergency 

response 

The probability of 

accidents always 

exists, but incident 

level is expected to 

remain low given 

safety awareness 

and safety protection 

measures. 

Potential for accidents 

expected to be low, 

but slightly greater 

than Alternative A as 

this alternative 

contemplates full 

project build-out. 

Same as Alternative 

B 

Same as Alternative 

B 

Possible impact to 

WAPA 115 kV 

electric 

transmission line 

Pilot Project has not 

caused any impacts 

to this transmission 

line. 

Project would obtain 

electricity from this 

line. Road crossings 

beneath line minimal 

and perpendicular to 

the line to avoid 

impacts. 

Non-electric 

alternative; no 

impacts to WAPA line 

anticipated. Road 

crossings beneath 

line minimal at 

perpendicular to line. 

Same as Alternative 

B 

Recreation 

Disruption to 

undeveloped 

recreational 

opportunities 

Public access to site 

is limited by 

checkerboard 

ownership pattern. 

Access to site from 

private surface is 

gated. Small extent 

of Pilot Project has 

not affected guided 

hunting opportunities 

in EIS analysis area. 

Similar to Alternative 

A in that public 

access to site would 

be limited. Guided 

hunting experience in 

EIS analysis area 

would be diminished 

given impacts to 

wildlife and the 

natural setting by 

construction, drilling, 

roads and well 

facilities. 

Similar to Alternative 

B, but no produced 

water is discharged 

into surface drainage 

channels. Temporary 

(20 o 30 years 

vegetation and wildlife 

benefits would not 

occur. 

Similar to Alternative 

B, but no produced 

water is discharged 

into surface drainage 

channels. Temporary 

(20 to 30 years) 

vegetation and wildlife 

benefits would not 

occur. 

2-42 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Disruption to 

developed 

recreation 

facilities 

No direct effect; no 

developed recreation 

facilities exist in Pilot 

Project area 

No developed 

recreation facilities 

exist in EIS analysis 

area; users of 

Dugway Recreational 

site may notice 

increased traffic on 

Carbon County Road 

351; fisherman at 

Coal Creek Bay area 

could be indirectly 

affected by 

construction and 

drilling activity. 

Same as Alternative 

B; fisherman at Coal 

Creek Bay area would 

be subject to higher 

operational noise 

levels than Alternative 

B given gas-powered 

facilities. 

Same as Alternative 

B 

Possible impacts 

to recreation 

users of Country 

Road 351 

(Seminoe Road) 

designated as 

national Back 

Country Byway. 

Pilot project is visible 

to visitors on the 

Back Country Byway, 

but it does not 

dominate the view, 

although it does not 

attract attention from 

viewpoints due to 

coloration f facilities. 

Similar to Alternative 

A, but increased well 

density and the 

associated road 

network would create 

an industrial setting 

along the Back 

Country Byway. 

Similar to Alternative 

B, but additional noise 

and emissions from 

gas-powered facilities 

would further degrade 

the Back Country 

Byway experience. 

Similar to Alternative 

B, but with the 

incremental increase 

of industrialization 

associated with the 

water re-injection 

pumping facilities. 

Disruption to 

recreation at 

Seminoe State 

Park and at 

Miracle Mile on 

the North Platte 

River 

No direct effect. Pilot 

Project is visible to 

recreational users 

traveling on Carbon 

County Road 351. 

Similar to Alternative 

A with construction, 

drilling, operational 

facilities and roads 

being noticeable to 

travelers on Carbon 

County Road 351. For 

some travelers, the 

feeling of solitude 

could be diminished 

from increased 

project traffic. 

Same as Alternative 

B 

Same as Alternative 

B 

Roads/Transportation 

Road use and traffic 

Maintenance 

impacts to Carbon 

County Road 351 

Negligible as Carbon 

County Road 351 

has been recently 

upgraded and traffic 

to Pilot Project is 

limited to operations 

workers. 

Construction to cause 

50% increase in traffic 

on Carbon County 

Road 351; expect 

increased 

maintenance needs 

for this road given 

construction traffic to 

involve more truck 

traffic. 

Same as Alternative 

B 

Same as Alternative 

B 

Potential for 

accidents with 

increased 

construction and 

operational traffic 

Negligible – Pilot 

Project only 

With increase in traffic 

on Carbon County 

Road 351, the 

possibility for projectrelated traffic 

accidents also 

increases. 

Same as 

Alternative B 

Same as Alternative 

B 

Seminoe Road Gas Development Project 2-43 
Draft Environmental Impact Statement November 2005

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Socioeconomics 

Projected project 

life 

Unknown; depends 

on amount of time 

needed to assess the 

natural gas potential 

of the site. 

Construction and 

drilling activities to 

occur over 10-year 

period. Total project 

life estimated at 30 

Same as Alternative 

B 

Same as Alternative 

B 

years. 

Employment 

Direct 

Indirect 

New Job 

Not Estimated 

50 – 110 

40 – 88 

90 – 198 

Similar to Alternative 

B 

Similar to Alternative 

B 

Opportunities 

Total estimated 

tax revenues over 

30-year project life 

Not applicable $480 million 

Similar but slightly 

less than Alternative 

B 

Similar by slightly less 

than Alternative B 

Estimated ad 

valorem property 

taxes over 30­

year project life 

Not applicable $121 million 

Similar but slightly 

less than Alternative 

B 

Similar but slightly 

less than Alternative 

B 

Estimated 

Wyoming Similar but slightly Similar but slightly 

severance taxes Not applicable $90 million less than Alternative less than Alternative 

over 30-year B B 

project life 

Estimated federal 

mineral royalties 

over 30-year 

project life 

Not applicable $186 million 

Similar but slightly 

less than Alternative 

B 

Similar but slightly 

less than Alternative 

B 

Estimated state 

mineral royalties 

from state 

administered 

lands over 30­

Not applicable $3 million 

Similar but slightly 

less than Alternative 

B 

Similar but slightly 

less than Alternative 

B 

year project life 

Estimated sales 

and use taxes 

over 30-year 

project life 

Not applicable $4 million 

Similar but slightly 

less than Alternative 

B 

Similar but slightly 

less than Alternative 

B 

Estimated 

corporate federal 

income taxes over 

30-year project life 

Not applicable $35 million 

Similar but slightly 

less than Alternative 

B 

Similar but slightly 

less than Alternative 

B 

Estimated direct 

and indirect Similar but slightly Similar but slightly 

employee related Not applicable $ 41 million less than Alternative less than Alternative 

taxes over 30­ B B 

year project life 

Low. Carbon County 

reports a vacancy 

rate of over 1,000 

Impacts to 

Rawlins housing 

utilities, public 

service, and 

present lifestyles 

Very low as a result 

of Pilot Project 

units for sale or rent 

(Rawlins has 500 

vacant units). Peak 

project demand for 

Seminoe Project 

estimated at 60 units, 

Similar to Alternative 

B 

Similar to Alternative 

B 

with 25-30 units of 

long-term demand. 

2-44 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Soils 

Potential for soil 

erosion 

No erodible soils 

found in Pilot Project 

area 

Approximately 19% of 

EIS analysis area 

covered with erodible 

soils; estimated 1,300 

acres of erodible soils 

to be disturbed. 

Similar to Alternative 

B 

Similar to Alternative 

B 

Potential for 

sedimentation 

Channel head cutting 

and erosion in Pool 

Table Draw where 

produced water from 

Discharge of 

produced water in 

drainage channels in 

EIS analysis area 

could contribute to 

Channel 

sedimentation 

potential is low 

because produced 

water to be 

Channel 

sedimentation 

potential is low 

because produced 

water to be injected 

Pilot Project channel erosion and discharged directly into underground 

discharged. down-channel 

sedimentation. 

into Seminoe 

Reservoir. 

“Dad Sandstone” 

formation. 

Revegetation 

potential of 

disturbed soils 

Low to Moderate Low to Moderate Same as Alternative 

B 

Same as Alternative 

B 

Vegetation 

Potential impacts 

to U.S. Fish & None. No threatened None. No threatened 

Wildlife and endangered and endangered plant Same as Alternative Same as Alternative 

threatened and plant species occur species occur in the B B 

endangered plant in Pilot Project area. EIS analysis area. 

species 

Potential impacts 

to Wyoming BLM 

sensitive plant 

species 

Persistent sepal 

yellow cress only 

BLM sensitive plant 

species known to 

occur in area. 

Produced water 

discharge in Pool 

Table Draw may 

enhance the 

development of this 

species, but effects 

would be reversed 

Persistent sepal 

yellow cress only BLM 

sensitive plant species 

known to occur in 

area. Produced water 

discharge in EIS 

analysis area 

drainages may 

enhance the 

development of this 

species, but effects 

would be reversed 

Low potential for 

effects to Persistent 

sepal yellow cress as 

produced water 

would be discharged 

directly into Seminoe 

Reservoir. 

Low potential for 

effects to Persistent 

sepal yellow cress as 

produced water would 

be injected 

underground. 

when water 

discharge ceases. 

when water discharge 

ceases. 

Potential impacts 

would be minimal as 

Potential impacts 

to wetlands and 

riparian areas 

Pilot Project road 

and well pad 

construction avoided 

wetland and riparian 

areas. 

construction 

disturbance would 

avoid wetland and 

riparian areas. Roads 

would cross drainage 

channels at right 

angles. 

Same as Alternative 

B 

Same as Alternative 

B 

Impacts to 

vegetation in 

drainages where 

produced water is 

discharged 

Increased vegetative 

cover and diversity of 

wetland and riparian 

species in Pool Table 

Draw below 

produced water 

discharge points. 

This would continue 

until discharge 

ceases. 

Increase in vegetative 

cover and diversity of 

wetland and riparian 

species drainages 

where produced water 

is discharged. This 

would occur until 

discharge ceases. 

Long-term discharge 

could cause increase 

in salt tolerant 

None. Produced 

water discharged 

directly to Seminoe 

Reservoir and North 

Platte River. 

None. Produced 

water to be injected 

underground. 

species. 

Seminoe Road Gas Development Project 2-45 
Draft Environmental Impact Statement November 2005

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Visual Resources 

Impact to 

Seminoe State 

Park 

recreationists 

No direct effects. 

Pilot Project not 

visible to Seminoe 

State Park 

recreationists. 

No direct effects. 

Travelers of Carbon 

County Road 351 

may notice drilling 

activities, as well as 

well pads and roads 

during project 

operations. Boaters 

on Seminoe 

Reservoir may see 

drill rig masts during 

drilling activities 

Same as Alternative 

B 

Same as Alternative 

B 

Impacts to 

travelers from 

Carbon County 

Road 351 

Travelers can see 

some of the Pilot 

Project facilities 

adjacent to Carbon 

County Road 351. 

Travelers would be 

able to observe 

construction and well 

drilling activities and 

operational well 

installations and 

roads adjacent to 

Carbon County Road 

351. Facilities that 

draw the attention of 

the viewer from 

Carbon County Road 

351 would exceed 

VRM Class II 

objectives. 

Same as Alternative 

B 

Same as Alternative 

B 

Impacts from 

Bennett Mountain 

Wilderness Study 

Area 

Portions of Pilot 

Project visible from 

ridges of Seminoe 

Mountains but view 

would be visible from 

nearly 10 miles 

away, which would 

diminish the visual 

impacts. 

Portions of the project 

activities within the 

EIS analysis area 

would be visible from 

ridges of Seminoe 

Mountains but view 

would be from nearly 

10 miles away, which 

would diminish the 

visual impacts. 

Same as Alternative 

B 

Same as Alternative 

B 

Wildlife (Terrestrial) 

Impacts to wildlife 

habitat 

Loss of 69 acres of 

wildlife habitat during 

Pilot Project 

operations. Habitat to 

be restored with 

reclamation after 

cessation of Pilot 

Project operations. 

Loss of 2,321 acres of 

wildlife habitat during 

long-term operations 

(1.7% of EIS analysis 

area). Habitat to be 

restored after 

cessation of 

operations in 30 yrs. 

Similar to Alternative 

B 

Similar to Alternative 

B 

Impacts to sage 

grouse 

No sage grouse leks 

in Pilot Project area 

and no sagebrush 

habitat directly 

disturbed. 

No direct disturbance 

in 0.25- mile radius of 

known sage grouse 

leks in the EIS 

analysis area. Nearly 

3,000 acres of 

sagebrush habitat 

would be disturbed, 

with approximately 

half of the habitat 

within 2–mile radius 

of sage grouse leks. 

Same as Alternative 

B 

Same as Alternative 

B 

2-46 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Project development 

would cause loss of 

Impacts to 

mountain plover 

Pilot Project 

disturbed 

approximately 146 

acres of mountain 

plover habitat, but 77 

acres of that 

disturbance has 

been reclaimed and 

returned to mountain 

plover habitat. 

approximately 850 

acres of the estimated 

43,000 acres of this 

habitat in the EIS 

analysis area over 30 

year project life (a 2% 

loss in mountain 

plover habitat). 

However, interim 

reclamation to 

grasses of nearly 

4,000 acres of 

Same as Alternative 

B 

Same as Alternative 

B 

disturbance would 

increase mountain 

plover habitat. 

Impacts similar to Impacts similar to 

Impacts to prairie mountain plover mountain plover Same as Same as Alternative 

dogs impacts under impacts under Alternative B B 

Alternative A. Alternative B. 

No crucial 

winter/yearlong 

Approximately 9,500 

acres of crucial 

pronghorn habitat in 

the Pilot Project 

winter/yearlong 

pronghorn habitat in 

Impacts to 

pronghorn 

area; however, 

displacement of the 

species during 

construction and 

drilling. Pronghorn 

the EIS analysis area; 

some displacement of 

the species expected 

in areas adjacent to 

construction and 

Same as Alternative 

B 

Same as Alternative 

B 

seem to be drilling. Pronghorn 

habituating to Pilot 

Project operations 

expected to habituate 

to operations traffic 

traffic and human and human presence. 

presence. 

No crucial winter No crucial winter mule 

mule deer range in 

the Pilot Project 

area; however, 

deer range in the EIS 

analysis area; 

however, 

Impacts to mule 

deer 

displacement of the 

species during 

construction and 

drilling. Mule deer 

seem to be 

habituating to Pilot 

Project operations 

traffic and human 

displacement of the 

species expected in 

areas adjacent to 

construction and 

drilling. Mule deer 

expected to habituate 

to operations traffic 

and human presence. 

Same as Alternative 

B 

Same as Alternative 

B 

presence. 

Ferruginous hawk 

generally avoids 

human activity and Same as Alternative 

Impacts to 

ferruginous hawks 

presence so 

construction and 

development likely to 

A but extended to the 

entire EIS analysis 

area. 

Same as Alternative 

B 

Same as Alternative 

B 

reduce foraging 

habitat. 

Seminoe Road Gas Development Project 2-47 
Draft Environmental Impact Statement November 2005

Issue/Concern Alternative A Alternative B Alternative C Alternative D 

Impacts to blackfooted ferret 

No black-footed 

ferrets sighted made 

within and 

surrounding Pilot 

Project during 

surveys in 2000, 

2001, 2002 and 

2003. No impacts to 

this species 

Black-footed surveys 

would continue to be 

conducted in whitetailed prairie dog 

towns greater than 

200 acres in size. 

Based on surveys 

conducted from 2000 

to 2003, no blackfooted ferrets have 

been sighted. Not 

likely to adversely 

affect this species 

Same as Alternative 

B 

Same as Alternative 

B 

Impacts to bald 

eagles 

No nesting or winter 

roosting habitat 

found in Pilot Project 

area. Some nesting 

and nesting habitat 

found along North 

Platte River South of 

Pilot Project area. 

Bald eagles may fly 

over area but no 

impacts expected to 

this species as a 

result of operations. 

Some nesting and 

winter roosting habitat 

found along North 

Platte River within 

and adjacent to the 

EIS analysis area. 

Federal laws and 

regulations prohibit 

any disturbance to 

within a 1-mile radius 

of nesting sites. Bald 

eagles may fly over 

area but no impacts 

expected to this 

species as a result of 

operations. 

Same as Alternative 

B 

Same as Alternative 

B 

Impacts to North 

Platte River 

species such as 

whooping crane, 

least tern, pallid 

sturgeon, Eskimo 

curlew and piping 

plover 

No suitable habitat 

for these species 

within or surrounding 

the Pilot Project 

area. No water 

deletions to affect 

these species. 

No suitable habitat for 

these species within 

or surrounding the 

EIS analysis area. No 

water depletions to 

affect these species. 

Discharge of 

produced water to 

area drainages could 

provide extra water to 

benefit these 

downstream species. 

No suitable habitat for 

these species within 

or surrounding the 

EIS analysis area. No 

water depletions to 

affect these species. 

Discharge of 

produced water to 

Seminoe Reservoir 

could provide extra 

water to benefit these 

downstream species. 

No suitable habitat for 

these species within 

or surrounding the 

EIS analysis area. No 

water depletions to 

affect these species. 

Notes: 

1. This table summarizes the potential impacts of the alternatives. Environmental impacts of each alternative 

are described in detail in Chapter 4, Environmental Consequences. This table also compares alternatives to 

the issue used to develop alternatives and those issues identified as being important to assess the impacts 

of the alternatives. Issues are identified in Chapter 1, Purpose of and Need for Action. When reviewing 

specific alternative actions, please note that there may be some minor differences in acres and volumes. 

These differences are due to rounding and are not important to the descriptions of the actions or their effects. 

2-48 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Chapter 3 – Affected Environment

This chapter describes the existing condition of the EIS analysis area and is provided to assist the 

reviewer in understanding the environmental consequences presented for each resource in 

Chapter 4, Environmental Consequences. The discussions are separated into individual resource 

topics such as air quality, soils, geology, surface water, ground water, etc. Resource specialists 

compiled existing and available information and, as appropriate, conducted on-the-ground surveys 

of the EIS analysis area. 

The EIS analysis area is the specific area within which proposed surface disturbance and 

development activities would occur. The study area is the area where direct and indirect effects to 

a specific resource would occur. For certain resources, such as soils and vegetation, the study 

area was considered to be the area of potential direct disturbance. For other resources, such as 

wildlife, transportation and socioeconomics, a broader study area was utilized to account for the 

potential off-site effects related to these resource categories. 

3.1 Air Quality/Climate

3.1.1 Regional Climate

The EIS analysis area is located in a semi-arid, steppe (dry and cold), mid-continental climate 

regime typified by dry windy conditions, limited rainfall, and long cold winters. 

Temperature and precipitation data for the Seminoe Dam and for the Rawlins airport are listed in 

Table 3.1-1, Temperature and Precipitation Data. Seminoe Dam is located approximately 7 

miles north of the EIS analysis area, while the Rawlins airport is located about 12 miles southeast 

of the EIS analysis area. See Figure 19, Regional Activity. 

Annual mean temperatures in this region of south-central Wyoming range from a low of about 

13°F in January to a high near 85°F in July. Prolonged cold conditions are frequent in the winter, 

with temperatures plunging below 0°F. Conversely, summertime temperatures can climb above 

100°F. 

Seminoe Road Gas Development Project 3­1
Draft Environmental Impact Statement November 2005

Table 3.1-1, Temperature and Precipitation Data for Rawlins, Wyoming 

Month 

Mean Temperature (°F) 

Daily Max Daily Min Mean 

Seminoe Dam Rawlins 

Airport Seminoe Dam Rawlins Airport Seminoe Dam Rawlins Airport 

January 30.0 33.4 12.5 12.5 21.3 23.0 

February 33.6 37.1 15.1 15.1 24.6 26.1 

March 40.6 45.5 19.7 22.1 33.0 33.8 

April 52.8 55.1 28.3 28.0 41.0 41.6 

May 63.7 65.7 37.4 36.1 50.8 50.9 

June 75.0 77.9 46.8 44.6 61.8 61.3 

July 83.6 85.3 53.8 50.5 68.6 67.9 

August 81.5 83.8 52.0 49.2 67.1 66.5 

September 71.3 73.3 42.7 40.5 57.1 56.9 

October 57.8 59.8 32.9 31.1 45.4 45.5 

November 41.4 42.9 22.6 20.1 31.7 31.5 

December 32.3 34.6 15.3 13.5 23.7 24.1 

ANNUAL 55.3 57.9 31.6 30.3 43.8 44.1 

Month 

Precipitation (inches) 

Mean Total As Snowfall Mean Snow Dept 

Seminoe Dam Rawlins 

Airport Seminoe Dam Rawlins Airport Seminoe Dam Rawlins Airport 

January 0.53 0.56 3.5 9.0 4 3 

February 0.65 0.52 5.9 7.7 5 2 

March 1.09 0.65 4.5 8.3 2 1 

April 1.62 1.06 1.4 7.3 0 Trace 

May 2.12 1.49 0.4 1.6 0 Trace 

June 1.39 0.93 0.3 0.3 0 Trace 

July 0.96 0.90 0.0 0.0 0 0 

August 0.75 0.81 0.0 0.0 0 0 

September 0.97 0.82 0.2 0.8 0 Trace 

October 1.13 0.86 1.6 4.2 0 Trace 

November 0.92 0.65 3.7 9.7 1 1 

December 0.65 0.49 4.2 8.4 3 2 

ANNUAL 12.78 9.74 26.0 57.3 - -

Source: Western Regional Climate Center. Period of record for both stations used in this table is 1971-2000. Seminoe 

Dam station is in Carbon County at an elevation of 6,838 feet (Latitude 42°09’N, Longitude 106°55’W). The Rawlins 

Municipal Airport Station is in Carbon County at an elevation of 6,736 feet (Latitude 41°48’N, Longitude 107°12’W). 

Annual precipitation typically ranges around 10 to 13 inches, with highest monthly amounts 

occurring in May. Snowfall is variable, and patterns are influenced by wind and topography and 

have an effect on vegetation, wildlife, hydrology and human activities. Summertime rain (June 

through August) is sporadic, often associated with passing thunderstorms, which can be locally 

intense. 

Wind directions can vary in this region, but the predominant wind direction is west to east as 

illustrated on Figure 21, Wind Rose – Rawlins, Wyoming. Wind roses depict the joint frequency 

of occurrence, in percentage, of wind speed and direction categories for a particular location and 

time period. The radials of the wind rose indicate the direction from which the wind is blowing. The 

length of the radials indicates the frequency of occurrence for that direction for certain wind speed 

3­2 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

classes. The annual-average wind speed for this area ranges between 10 to 15 miles per hour 

(mph); with gusts frequently above 30 mph. Calm conditions rarely occur. 

3.1.2 Ambient Air Quality Standards

The Federal Clean Air Act requires the EPA to set ambient air quality standards (AAQS) to protect 

public health and welfare. These standards were developed to protect public health (primary 

standards) with a margin of safety. EPA also has specified secondary standards that are more 

restrictive than the primary standard in instances when a primary standard does not adequately 

protect public property or resources (for example, ensuring that dust concentrations are low 

enough to prevent damage to crops or soiling of buildings). Further, the state of Wyoming has 

adopted ambient standards for SO2 and H2S that are more restrictive than EPA’s limits. 

The Prevention of Significant Deterioration (PSD) program set forth by 40 CFR 52.21 is designed 

to prevent the deterioration of air quality to the AAQS levels. EPA has established ambient air 

increments for selected air pollutants that limit incremental concentration increases of the 

selected pollutants. The allowable increments vary in magnitude depending upon the classification 

of the region regulated. Special areas that warrant greater protection, such as national parks and 

wilderness areas, are classified as Class I areas. Class II areas generally have less restrictive air 

quality standards that allow possible development. Applicable AAQS and ambient air increments 

are listed in Table 3.1-2, Ambient Air Quality Standards. 

3 Table 3.1-2, Ambient Air Quality Standards and Air Increments (μg/m ) 

Pollutant Averaging Time 

Ambient Air Quality Standards PSD Ambient Air Increment 

National Wyoming Class I Class II 

CO 1-hour 40,000 40,000 None 8-hour 10,000 10,000 

NO2 Annual 100 100 2.5 25 

O3 

1-hour 235 235 None 8-hour 157 157 

PM10 

24-hour 150 150 8 30 

Annual 50 50 4 17 

PM2.5 

24-hour 65 65 None Annual 15 15 

3-hour 1,300 1,300 25 512 

SO2 24-hour 365 260 5 91 

Annual 80 60 2 20 

3.1.3 Regional Air Quality

No air quality monitoring has been conducted within the EIS analysis area. However, air quality 

constituents that have been measured throughout the region indicate that existing air quality in 

Seminoe Road Gas Development Project 3­3
Draft Environmental Impact Statement November 2005

south-central Wyoming is generally good and achieves all state and national AAQS. Regional air 

quality data representative of the EIS analysis area is summarized in Table 3.1-3, 

Representative Background Ambient Air Concentrations. 

Atmospheric deposition refers to the processes by which air pollutants are removed from the 

atmosphere and deposited on terrestrial and aquatic ecosystems, and it is reported as the mass 

of material deposited on an area per year (kilograms per hectare per year). Air pollutants are 

deposited by wet deposition (precipitation) and dry deposition (gravitational settling of pollutants). 

3 Table 3.1-3, Representative Background Ambient Air Concentrations (μg/m ) 

Pollutant Averaging Period Measured Background Concentration 

CO1 1-hour 3,336 

8-hour 1,381 

NO2 2 Annual 3.4 

O3 3 1-hour 169 

8-hour 147 

PM10 4 24-hour 33 

Annual 16 

PM2.5 4 24-hour 13 

Annual 5 

SO2 5 

3-hour 132 

24-hour 43 

Annual 9 

Notes: 

1. Data collected by Amoco at Ryckman Creek for an 8-month period during 1978-1979 as 

summarized in the Rile Ridge EIS (BLM 1983) 

2. Data collected at the Green River Basin Visibility Study Site, Green River, Wyoming, between 

January and December 2001 (Air Resource Specialists 2002) 

3. Data collected at the Green River Basin Visibility Study Site, Green River, Wyoming, between 

June 10, 1998 and December 31, 2001 (Air Resource Specialists 2002) 

4. Data collected by Wyoming DEQ, Air Quality Division at the Emerson Building, Cheyenne, 

Wyoming, for Year 2001. Second highest concentrations are listed for 24-hour averages 

5. Data collected at the LaBarge Study Area, Northwest Pipeline Craven Creek Site, 1982-1983 

Total deposition (wet and dry) reported as total sulfur and total nitrogen deposition for each of 

these sites for year 2001 is provided in Table 3.1-4, 2001 Measured Acid Deposition Data 

(kg/ha-yr). 

Table 3.1-4, 2001 Measured Acid Deposition Data (kg/ha-yr) 

Site Location Nitrogen Deposition Sulfur Deposition 

Pinedale 1.6 0.8 

Centennial/Brooklyn Lake 7.5 2.8 

Total deposition levels of concern (LOC) have been estimated for several areas, including the 

Bridger Wilderness Area. The “red line” LOC is defined as the total deposition that the area can 

tolerate and the “green line” LOC is defined as the acceptable level of total deposition. Cumulative 

3­4 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

impacts plus background are compared to these LOCs. The Bridger Wilderness nitrogen 

deposition red line LOC is 10 kg/ha-yr and nitrogen deposition green line LOC is 3-5 kg/ha-yr. The 

Bridger Wilderness sulfur deposition red line LOC is 20 kg/ha-yr and sulfur deposition green line is 

5 kg/ha-yr. 

The levels of concern used for comparison in the deposition analysis have been a topic of 

discussion between the BLM and the Forest Service for the past few years. The Forest Service 

has expressed some concern that the LOC values are too high; but this agency has not, however, 

provided input as to what values would be more acceptable. These LOC values are presently the 

only comparison values available and have been in use for most acid deposition analyses 

conducted since the mid 1990s. 

Site-specific lake chemistry background data (pH, acid neutralizing capacity, elemental 

concentrations, etc.) have been collected by the U.S. Geological Survey (Water Quality Division) 

in several high mountain lakes within wilderness areas in Wyoming and northern Colorado. Lake 

acidification is measured in terms of change in acid neutralizing capacity (ANC), which is the 

lake’s buffering capacity to resist acidification from atmospheric deposition of acid compounds 

such as sulfates and nitrates. Measured baseline ANC data for sensitive lakes within the 

cumulative study domain are provided in Table 3.1-5, Monitored Background Conditions at 

Sensitive Lakes. 

Table 3.1-5, Monitored Background Conditions at Sensitive Lakes 

Sensitive Lake Lake Location Background ANC 

(μeq/l)

1 

Number of 

Samples 

Period of 

Monitoring 

Black Joe Lake Bridger Wilderness Area 67.0 61 1984-2003 

Deep Lake Popo Agie Wilderness Area 59.9 58 1984-2003 

Hobbs Lake Bridger Wilderness Area 69.9 65 1984-2003 

Lazy Boy Lake Bridger Wilderness Area 18.8 1 1997 

Upper Frozen Lake Bridger Wilderness Area 5.0 6 1997-2003 

Ross Lake Fitzpatrick Wilderness Area 53.5 44 1988-2003 

West Glacier Lake Glacier Lakes Ecosystem 

Experiments Sites (GLEES) 35.2 14 1988-1996 

Lake Elbert Mount Zirkel Wilderness Area 51.9 55 1985-2003 

Seven Lakes Mount Zirkel Wilderness Area 36.2 55 1985-2003 

Summit Lake Mount Zirkel Wilderness Area 47.3 95 1985-2003 

Lower Saddlebag 

Lake Popo Agie Wilderness Area 55.5 43 1989-2003 

Island Lake Rawah Wilderness Area 68.7 15 1996-2002 

Kelly Lake Rawah Wilderness Area 181.1 13 1995-2202 

Rawah #4 Lake Rawah Wilderness Area 41.2 13 1996-2002 

Note: 

1. 10th Percentile Lowest ANC values reported. Values provided by Terry Svalberg U.S. Forest Service. 

Seminoe Road Gas Development Project 3­5
Draft Environmental Impact Statement November 2005

Lakes with ANC values ranging from 25 to 100 microequivalents per liter (μeq/l) are considered to 

be sensitive to atmospheric deposition, lakes with ANC values ranging from 10 to 20 μeq/l are 

considered very sensitive, and lakes with ANC values less than 10 μeq/l are considered extremely 

sensitive. 

The Forest Service has identified specific “Level of Acceptable Change” (LAC) values, which are 

used to evaluate potential air quality impacts from deposition within their wilderness areas (USFS 

2000). The Forest Service has identified a LAC of no greater than 1 μeq/l change in ANC (from 

human causes) for lakes with existing ANC levels less than 25 μeq/l. A limit of 10% change in 

ANC reduction was adopted for lakes with existing ANC greater than 25 μeq/l. 

The EIS analysis area is located in the Hanna Basin, in an area known as the Laramie Air Basin, 

which includes much of south-central Wyoming. This basin is bordered by the Wyoming-Colorado 

state line to the south, the Laramie Mountains to the east, the Granite Mountains to the north, and 

the Great Divide Basin to the west. Air transport from the west and southwest dominates in level 

terrain areas, and dispersion results from unstable conditions induced by surface heating during 

the day. Conditions generally stabilize at night as air temperatures cool. 

The EIS analysis area is located within a PSD Class II area, where the release of limited 

concentrations of certain pollutants is permitted as long as the AAQS are maintained, and 

modeled concentrations of increment-consuming sources are below stipulated PSD Class II 

increments. 

The nearest PSD Class I area (an area where little air quality deterioration is allowed) is the 

Savage Run Wilderness Area, located approximately 47 miles south-southeast of the EIS analysis 

area. Another PSD Class I area in the region is the Mount Zirkel Wilderness Area, located in 

northern Colorado about 57 miles south of the EIS analysis area. The proximity of the proposed 

Seminoe Road Project to Class I areas is shown on Figure 20, Air Quality Modeling Domain. 

3.1.4 Air Permitting Requirements for Industrial Sources

Wyoming industrial sources must secure a Construction Permit as required by Wyoming Air 

Quality Regulations, Chapter 6, Section 2 from the Wyoming DEQ, Air Quality Division prior to 

commencing construction of any source that has the potential to emit regulated air pollutants (see 

Appendix D, Agency Jurisdictions (Permits and Approvals). 

3­6 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

The Wyoming DEQ, Air Quality Division imposes stringent requirements for large industrial 

sources under a PSD program. PSD permitting applies only to projects that emit 250 tons per year 

or more of PM10, NOX, CO, SO2 or other regulated air pollutants from stationary, non-fugitive 

sources. Non-fugitive sources are air pollutants that are typically emitted to the atmosphere 

through a vent or stack. The Seminoe Road Project is not expected to be subject to PSD 

permitting regulations because non-fugitive emissions would be low. 

3.2 Soils

Information for the soils occurring to the north and west of the North Platte River and Seminoe 

Reservoir was provided by the BLM office in Rawlins, Wyoming (Foley 2002, Foley 2004, Simons 

2003). (See Figure 22, Soils Map.) The information collected from the BLM included a general 

soils map providing an overview of the general soils present, a more detailed Order 3 soils map, 

and map unit and pedon descriptions. An interpretations table was also provided by the BLM 

depicting ratings for the majority of the map units occurring within the entire project area with 

respect to runoff potentials, water and wind erosion hazards, and the presence of elevated salt 

and sodium levels. This table provided the basic information used to identify and characterize 

potentially sensitive soils (saline/sodic, shallow, and highly erodible soils) on site. 

Soil maps, map unit descriptions, and pedon descriptions for the remainder of the project area 

were provided by the Natural Resources Conservation Service (NRCS) (Cox 2004). Pertinent 

maps and descriptions on file in the NRCS Office in Saratoga, Wyoming were copied and the map 

unit boundaries drawn on a project map. The data gathered were the result of various contract soil 

surveys managed by the NRCS and remain unpublished at this time. For the area south of 

Seminoe Reservoir where no surveys had been conducted, existing soils data and mapping were 

used to interpolate the soil map units that could occur within this area. 

The following section was based on the maps and data collected from these sources. Soil 

chemical and physical characteristics related to impact assessment, mitigation planning, and 

potential revegetation success are stressed. Appendix N, Soils and Vegetation Information, 

supports this discussion and identifies the map units overlying a majority of the project area 

across the dominant topographic features. 

Seminoe Road Gas Development Project 3­7
Draft Environmental Impact Statement November 2005

3.2.1 General Soil Characteristics

Soils range from shallow to deep with shallow soils dominating ridges, residual uplands, hills, and 

knolls. Deeper soils are most common on terraces, alluvial fans, floodplains, and bottomlands. 

Surficial textures are generally sandy and loamy in nature. Heavy clay textures are uncommon. 

High profile coarse fragment contents are usually limited to soils overlying ridge, uplift, and similar 

topographic features. 

The soils are typically alkaline with pH values of 7.5 to 8.8. High alkalinity, coupled with high soil 

salinity values, is a common condition associated with alluvial fans, bottomland, drainage bottom, 

pediment, and some upland topographic features. Saline soil profiles are more common in the 

northern portion of the EIS analysis area. 

Available water capacities range from low to high depending upon soil depth and texture, with 

effective rooting depths following a similar pattern. Water erosion hazards range from slight to 

severe. With moderate to severe ratings most common, wind erosion hazards are typically 

moderate, although a number of the soils are subject to higher hazards. 

No prime farmland soil units occur in the EIS analysis area (Cox 2004). 

Soils classed as “sensitive” include soils having physical or chemical characteristics that could 

inhibit the revegetation of sites disturbed by construction or operational activities. Such soils 

include saline/sodic soils, soils overlying steep slopes, shallow, and highly erodible soils. These 

soils are described later in this section. It should be noted that the acreage calculations developed 

were based essentially on worst-case interpretations pertaining to soil mapping units as a whole. 

For example, a map unit made up of two soils, one of which is deep and one shallow, would have 

been classed as shallow in its entirety thereby skewing the map to display a worst-case scenario. 

This approach was unavoidable given the baseline data, map unit interpretations, and map scales 

available. 

3.2.2 Saline/Sodic Soils

Saline and sodic soils typically occur on alluvial fans, terraces, bottomlands, and some residual 

uplands and pediment formations. Figure 23, Saline and Sodic Soils depicts areas overlain by 

soil map units that contain all or in part, soils that may be classed as saline and/or sodic. Saline 

soils are characterized by increased levels of soluble calcium, magnesium, and sodium salts 

3­8 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

resulting in electrical conductivities (ECs) greater than 4.0 milliohms per centimeter. These 

conditions result in droughty soils due to the salt compounds present that absorb soil moisture or 

otherwise render soil moisture unavailable to plant species. Sodic soils are typified by high levels 

of exchangeable sodium in the soil complex. Soils classed as sodic have SARs of 12 (unitless 

value) or greater. Increased soil sodium levels can cause soil particles to disperse resulting in 

reduced soil infiltration and permeability, particularly during wetting and drying cycles, resulting in 

a droughty seedbed with limited air exchange. These effects are most prevalent, and have the 

greatest negative impact on plant growth, when occurring in fine textured soils having high clay 

percentages. 

Saline and sodic soils can form as a result of the weathering of parent materials high in salts or 

sodium or as a result of the deposition of these chemical constituents via sedimentation, overland 

flows, or flooding. Although neither salt nor sodium are toxic to plants, per se, high levels of either 

can reduce plant establishment, growth, and productivity, as well as limit the variety of plant 

species adapted to such conditions. 

The revegetation potential of saline and sodic soils is directly related to the level of salts and 

sodium in the soil complex, as well as to soil texture, depth, moisture regime, etc.; higher levels 

generally, the lower the potential for the soil to support a diverse, productive plant community. 

3.2.3 Shallow Soils

Shallow soils are generally characterized by a depth of 20 inches or less to bedrock or other 

layers incapable of serving as a growth medium. These soils have developed in association with 

steeper slope topographic positions and in conjunction with less weatherable parent material 

formations on low ridges, residual/sloping uplands, undulating hills, and low knolls. (Figure 25, 

Shallow Soils). Shallow soils are not typical of alluvial fans, pediments, terraces, and 

bottomlands. Shallow soils, by definition, are characterized by shallow rooting depths having 

limited fertility levels and low available water holding capacities. Overall, the revegetation 

potentials for shallow soils are considered to be limited given the edaphic characteristics noted. 

Mitigation techniques do exist whereby revegetation constraints associated with this soil condition 

can be reduced or overcome. 

Seminoe Road Gas Development Project 3­9
Draft Environmental Impact Statement November 2005

3.2.4 Soils Overlying Steep (>25 Percent) Slopes)

Soils overlying steep slopes are depicted on Figure 24, Steep Slope Soils. Steep slopes of the 

project area are typically found in association with ridge, rolling upland and prominent uplift 

formations. While soil depths ranging from shallow to moderately deep may occur across steeper 

slopes, shallow to very shallow soils are the norm. Soil depths on steep slopes are limited by a 

variety of factors including shallow depths to bedrock, as noted above, and increased surface 

runoff and erosion potentials. Shallow soil map units on steeper slopes may also include surface 

rock exposures and rock outcrop formations having little to no soil cover. Further, soils on steeper 

slopes may contain a higher percentage of coarse fragments (gravels, cobbles, and stones) 

throughout the profile. These characteristics, acting individually or in concert, serve to limit the 

revegetation potential of steep slope sites by limiting soil fertility and the soil moisture available for 

plant establishment and growth. Steep slope conditions may also limit soil salvage and handing 

efficiencies as well as the application of desirable revegetation techniques. 

3.2.5 Highly Erodible Soils

Highly erodible soils include those soil map units, all or in part, that are considered to have severe 

susceptibilities to the erosive forces of wind and/or water (Figure 26, Erodible Soils). Wind 

erosion susceptibility is a function of soil structure, surface roughness, wind speed and direction, 

soil moisture, “field” length, and vegetative cover. A dry soil supporting little in the way of 

vegetation and having a sandy surface texture overlying a long, smooth unbroken topography 

would typically be considered to have a severe wind erosion potential. Conversely, a moist clay 

loam-textured soil supporting a dense stand of vegetation across a rough surface topography 

would typically be considered to have a slight susceptibility to wind erosion. The soil map units of 

the project area exhibit, in the main, moderate wind erosion susceptibilities. Soil map units having 

severe susceptibilities are somewhat rare across the project area. 

Water erosion is a function of precipitation regimes, soil surface physical characteristics (texture, 

structure, coarse fragment content), slope angle and length, vegetation cover, and any practices or 

natural features that promote soil stability. A silty soil overlying a long, steep, sparsely vegetated slope 

would be considered to have a severe water erosion hazard. A loam soil, supporting a dense stand of 

vegetation and overlying a nearly level slope broken by an undulating topography would typically have 

a slight erosion hazard. A partial surface cover of gravels reducing the percent of exposed soil would, 

in turn, further reduce susceptibility. The likelihood of water erosion occurring to the greatest extent is 

3­10  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

correlated with the spring snowmelt period and intense summer thunderstorms that give rise to 

increased runoff and flooding. Soil map units having, all or in part, severe water erosion potentials are 

common across the proposed project area and generally correlate with high runoff potentials. 

Revegetation potentials of soils having high erosion susceptibilities are considered to be low to 

moderate under ideal erosion - inducing conditions. However, conservation practices can be 

employed that dramatically reduce susceptibilities and underscore the positive chemical and 

physical characteristics of impacted soil map units. 

3.2.6 Areas of Sensitive Soil Concentrations

Areas within the project boundaries exhibiting a combination of saline/sodic soil characteristics, 

shallow soil depths, and severe erosion potentials are depicted on Figure 27, Areas of Sensitive 

Soil Concentrations. The revegetation potentials of such sites are constrained by a combination 

of these three sensitive soil characteristics. Mitigation of such sites would require that soil 

handling and revegetation techniques designed to address all of these constraints be employed to 

achieve revegetation goals and objectives. 

3.2.7 Cryptobiotic Soils

Cryptobiotic soils have recently become of greater concern to the BLM in terms of the ability of 

these types of soils to stabilize essentially undisturbed soil surfaces and enhance the growth of 

plant species in semi-arid areas. The EIS analysis area has not been inventoried for cryptobiotic 

soils, but they are found throughout semi-arid areas of the western U.S., often in association with 

pinyon-juniper vegetation. The EIS analysis area has very limited juniper vegetation. See Section 

3.6.11, Juniper. 

Cryptobiotic soils are biological soil crusts typically composed of cyanobacteria, green algae, 

lichens, mosses, microfungi and other bacteria (Beinap et al 2001). These crusts resemble a 

rough “carpet” on the surface of the soil, which reduces wind and water erosion, fixes nitrogen, 

and adds to the soil organic matter (Eldridge and Green 1994). The soil crust is essentially a 

matrix of bacteria and other organic matter that binds soil particles together (Beinap 1995). 

3.3 Geology

The characteristics of the geology, specifically the coal seam deposits, dictate the most 

economical and practical method of coalbed natural gas development in the EIS analysis area. 

Seminoe Road Gas Development Project 3­11
Draft Environmental Impact Statement November 2005

Geologic data and the interpretations form the basis for gas extraction by providing coal seam 

location and general geologic structure data (such as strike, dip, faults, fracture patterns, etc.). 

3.3.1 General Geology

The EIS analysis area is situated in the western portion of the Hanna Basin. The Shirley and 

Seminoe mountains bound the northern part of the basin; the St. Mary’s and Pass Creek 

anticlines form the southern edge of the basin, the Rawlins Uplift bounds the basin on the west, 

and the eastern margin of the basin is defined by the Simpson Ridge anticline that separates the 

Hanna Basin from the Carbon Basin. 

The geology at the site is shown on Figure 28, Regional Geology and includes a thick sequence 

of sedimentary rocks as shown on Figure 29, General Stratigraphic Column and Geologic 

Cross-Section A-A’. 

The targeted zones for natural gas extraction in the EIS analysis area include the deeper 

Mesaverde coals and the shallower Medicine Bow/Fox Hills coals. See Figure 29, General 

Stratigraphic Column and Geologic Cross-Section A-A’. 

Productive windows of natural gas extraction range from depths of 500 to 14,000 feet for the 

Mesaverde coals, with production depths of 500 to 10,000 feet for the overlying Medicine Bow/Fox 

Hills coals. The apparent duplication of production horizons is due to the locally steep dip of the 

Cretaceous age formations, which plunge east into the Hanna Basin at dips of 10 to 15 degrees. 

Both sets of coal targets outcrop at different points on the surface near the western edge of the 

Hanna Basin and rapidly dip to over 30,000 feet just 25 miles east of the outcrop. 

Faulting is common within the Hanna Basin. A major thrust fault separates the Hanna Basin from 

the pre-Cambrian rocks to the north. Faults within the EIS analysis area are typically normal faults 

with a northerly trend. See Figure 28, Regional Geology. Cross faulting between major trending 

fault systems is also common, and major faults typically occur within 500 feet of one another. 

3.3.2 Geologic Hazards

The seismic activity potential at the EIS analysis area is considered low. Twenty-five magnitude 

2.0 or greater earthquakes have been recorded in Carbon County (Case et al. 2002). Most of the 

recorded earthquakes occurred in the 1970’s. The most recent earthquake in the region was 

3­12 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

recorded in February 2000 with the epicenter located 27 miles northwest of the town of Hanna; 

this earthquake had a magnitude of 3.0 (Case et al. 2002). 

Geologic hazards, such as landslides, are rare in the EIS analysis area because of the generally 

low topographic relief. However, isolated minor mass movements are found along drainage 

banks. 

3.3.3 Paleontology

The EIS analysis area is primarily underlain by Cretaceous age deposits of the Lewis Shale and 

Medicine Bow formations and late Cretaceous/early Tertiary age strata of the Ferris Formation. 

No significant fossil-bearing sites have been reported in the EIS analysis area. 

3.4 Surface Water

This section discusses the regional hydrologic setting, flow characteristics of surface drainages, 

and surface water quality within the EIS analysis and surrounding areas. 

The following information resources were used for this evaluation: 

� Surface water quality and quantity historical data collected by the United States


Geological Survey (USGS);


� Surface water quality and quantity data collected for the Seminoe Road Pilot Project by 

the Proponent; and 

� Surface water-monitoring data collected by the BLM for the Seminoe Road Pilot Project. 

3.4.1 Hydrologic Setting

The EIS analysis area and surrounding region contains perennial rivers (North Platte and 

Medicine Bow rivers), Seminoe Reservoir, an intermittent stream (O’Brien Creek), stock ponds, 

playas, many ephemeral stream channel systems, and downstream water resources such as the 

Miracle Mile tail-water fishery and Pathfinder Reservoir used for irrigation storage. 

There are numerous stock ponds and playas in the area that may receive Project produced water 

under some of the alternatives. 

Seminoe Road Gas Development Project 3­13
Draft Environmental Impact Statement November 2005

The North Platte and Medicine Bow rivers supply most of the water to Seminoe Reservoir during 

snow melt from the Medicine Bow, Snowy Mountains, Sierra Madres and other mountain ranges 

located in Colorado and Wyoming, but can have high flows in response to spring, summer and fall 

storm events (see hydrograph figures). Ephemeral channels occur throughout the Seminoe Road 

Project area and only flow in response to storm events. 

The climate of the Seminoe Road Project area is arid with precipitation averaging 9-13 inches per 

year depending on elevation and geography. The mean annual precipitation measured on 

Seminoe Dam from 1948 to 2004 was 12.8 inches and mean annual precipitation measured near 

the town of Rawlins from 1951-2004 was 9.2 inches. Typical storm patterns in the Seminoe Road 

Project area are influenced by the North Platte River valley and surrounding uplifts such as the 

Haystack Ferris, and Seminoe mountains. Winter snow precipitation is subject to sublimation and 

wind deposits making spring melting events short lived and mainly in response to individual 

snowstorms. Spring has the highest monthly precipitation with May being the wettest month for 

both Rawlins and Seminoe Dam. Convective thunder storms in the spring, summer and late 

summer account for the most intense storms and can be very localized resulting in short duration 

precipitation of 0.5 to over 2 inches in a day (WRCC, 2005). During storm events, flooding in 

ephemeral drainages can result in substantial local erosion and sediment deposition. 

3.4.2 North Platte River

The EIS analysis area is located in the North Platte River drainage basin. See Figure 30, Platte 

River Drainage Basin. The North Platte River flows from its source in northern Colorado into 

south-central Wyoming, passes through a series of water storage and power generation projects, 

then flows eastward into Nebraska, where it merges with the South Platte River. The Platte River 

ultimately flows into the Missouri River. 

Flows in the North Platte River upstream of Seminoe Reservoir are unregulated; however, 

downstream of the Kortes Reservoir, North Platte River flows are influenced by reservoir 

discharges. North Platte River reservoirs provide and store water for irrigation, are utilized for 

hydroelectric power production, municipal and industrial water supplies, and provide for flood 

control, recreation, and fish and wildlife habitat. Additional information and details about the 

Seminoe, Kortes and Pathfinder dams and reservoirs along the North Platte River are set forth in 

Appendix E, Regional Activity. 

3­14 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.4.2.1 General Overview of the North Platte Drainage System

The EIS analysis area is situated within the Hanna Basin, which is drained by the North Platte 

River. See Figure 31, Hanna Basin. The total surface relief of the Hanna Basin is approximately 

1,600 feet with elevations reaching a maximum of about 7,900 at Pass Creek Ridge and a 

minimum of about 6,300 feet at Seminoe Dam. The Medicine Bow River is a major tributary to the 

North Platte River within the Hanna Basin and has its confluence with the North Platte in the 

central part of the Seminoe Reservoir. Other prominent drainages that are tributary to the North 

Platte River in the Hanna Basin include the Walcott Ditch, St. Mary’s Ditch, Big Ditch, Middle Ditch 

and North Ditch. 

Seminoe Reservoir bisects the eastern portion of the EIS analysis area. Downstream of Seminoe 

Reservoir, the North Platte River flows into and out of Kortes Reservoir, through a stretch known 

as “Miracle Mile” and finally into Pathfinder Reservoir. See Figure 30, Platte River Drainage 

Basin, and Appendix E, Regional Activity. 

The Wyoming DEQ categorizes Wyoming streams and rivers into different water quality “classes.” 

Water classes are a hierarchical categorization of waters according to existing and designated 

uses. The regulations defining water classes and other water quality standards are promulgated 

pursuant to Wyoming Statute 35-11-101 through 1507 specifically 302 (a) (i) and 302 (b) (i) and 

(ii). Examples of surface waters and their classes are presented in Table 3.4-1, Summary of 

Surface Water Classes and Uses. 

Table 3.4-1, Summary of Surface Water Classes and Uses 

Water 

Classification Streams 

Surface Water 

Type 

Protected Uses Comments 

Class 1 

North Platte River 

from the headwaters 

of Pathfinder 

Reservoir upstream 

to Kortes Dam 

(“Miracle Mile” 

segment) and some 

reaches of the North 

Platte River up 

stream of the Project 

area 

Perennial, 

intermittent, or 

ephemeral 

Water quality, physical, and 

biological integrity 

Outstanding waters, non 

degradation by point 

sources, surface waters in 

parks or wilderness areas 

Class 2 

Perennial, 

intermittent, or 

ephemeral 

Fisheries and drinking water 

Waters other than those 

designated Class 1 that 

support fish or drinking 

water 

Seminoe Road Gas Development Project 3­15
Draft Environmental Impact Statement November 2005

Water 

Classification Streams 

Surface Water 

Type 

Protected Uses Comments 

Class 2AB 

N Platte R 

(Remainder) 

Seminoe Reservoir 

Medicine Bow River 

Perennial, 

intermittent, or 

ephemeral 

Game fisheries, drinking water, 

non-game fisheries, fish 

consumption, aquatic life other 

than fish, recreation, wildlife, 

industry, agriculture, and scenic 

value 

Waters known to support 

game fisheries and used as 

a drinking water source 

Class 2A None in Project Area 

Perennial, 

intermittent, or 

ephemeral 

Drinking water, non-game fish, 

aquatic life other than fish, 

recreation, wildlife, industry, 

agriculture, and scenic value 

Waters not known to 

support game fish but used 

as a drinking water source 

Class 2B None in Project Area 

Perennial, 

intermittent, or 

ephemeral 

Game fisheries, non-game 

fisheries, fish consumption, 

aquatic life other than fish, 

recreation, wildlife, industry, 

agriculture, and scenic values 

Water known to support 

game fish but not used for 

drinking water 

Class 2C None in Project Area 

Perennial, 

intermittent, or 

ephemeral 

Non-game fish, aquatic life other 

than fish, recreation, wildlife, 

industry, agriculture, and scenic 

value 

Water known to support 

non-game fish 

Class 3 

Intermittent, 

ephemeral, or 

isolated 

including 

wetlands 

Aquatic life other than fish, 

recreation, wildlife industry, 

agriculture, and scenic value 

Not known to support fish 

or used as a drinking water 

source 

Class 3A None in Project Area Wetlands or 

isolated 

Aquatic life other than fish, 

recreation, wildlife, industry, 

agriculture, and scenic value 

Not known to support fish 

or used as a drinking water 

source 

Class 3B 

All proposed 

discharge drainages 

and playas in the EIS 

Analysis Area 

Intermittent, 

ephemeral, or 

isolated waters 

including 

wetlands 

Aquatic life other than fish, 

recreation, wildlife, industry, 

agriculture, and scenic value 

Generally characterized as 

frequent linear wetland 

occurrences or 

impoundments within or 

adjacent to the stream 

channel 

Class 3C None in Project Area 

Perennial 

streams with 

wetland 

characteristics 

Aquatic life other than fish, 

recreation, wildlife, industry, 

agriculture, and scenic value 

Includes geothermal waters 

and waters with high 

concentrations of salts, 

metals, or extreme pH 

Class 4 

Perennial, 

intermittent, 

ephemeral, 

artificial 

Recreation, wildlife, industry, 

agriculture, and scenic value 

Waters now known to 

support aquatic life 

Class 4A Big Ditch, Middle 

Ditch, North Ditch 

Artificial canals 

or ditches 

Recreation, wildlife, industry, 

agriculture, and scenic value 

Waters not known to 

support aquatic life 

Class 4B None in Project Area 

Intermittent or 

ephemeral 

stream channels 

Recreation, wildlife, industry, 

agriculture, and scenic value 

Infrequent wetland 

occurrences or 

impoundments within or 

adjacent to stream 

channels not known to 

support aquatic life 

Class 4C None in Project Area 

Intermittent, 

ephemeral, or 

artificial stream 

channels 

Recreation, wildlife, industry, 

agriculture, and scenic values Effluent dominated streams 

Adapted from WDEQ, 2001 

3­16  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.4.2.2 North Platte River Upstream of Seminoe Reservoir

The Wyoming DEQ classifies the North Platte River within the EIS study area and above Seminoe 

Reservoir as Class 2AB surface water. 

Average, minimum and maximum monthly flows for the North Platte River above Seminoe 

Reservoir are shown in Figure 32, Summary of Flow Data. The monthly averages shown in this 

figure include data from the full period of record, December 1960 – August 2002 (HydroGeo 

2003a). The flow-monitoring location is shown on Figure 33, Hydrologic Monitoring Sites 

Location Map. Flows are generally highest in the spring. Maximum daily flows as high as 15,000 

cfs are possible during May and June; however, during drought cycles, maximum daily flows in 

spring months may be as low as 1,000 cfs. Flows are much lower in the fall months, and flows 

less than 50 cfs have been observed. 

Water in the North Platte River above Seminoe Reservoir is calcium bicarbonate type with slightly 

alkaline pH. The USGS and the Proponent have compiled baseline and background water quality 

measurements for the North Platte River (USGS 2004, BLM 2001, HydroGeo et al. 2001, 

HydroGeo 2001 and 2003a). A summary of water quality data is presented in Figure 34, 

Summary of Surface Water Salinity Data. These data were collected at the monitoring locations 

shown on Figure 33, Hydrologic Monitoring Sites Location Map. 

The water quality in the North Platte above Seminoe Reservoir varies with flow volume and, thus, 

exhibits seasonal changes. TDS, specific conductivity, and concentrations of calcium, 

magnesium, sodium and chloride are lowest during the high-flow months May and June. The 

variability in water quality in the North Platte Rive above Seminoe Reservoir is relatively high 

(Figure 34, Summary of Surface Water Salinity Data). 

3.4.2.3 Seminoe Reservoir

The construction and operation of Seminoe Reservoir has substantially impacted the surface 

water flows of the North Platte River downstream of Seminoe Reservoir. Seminoe Reservoir 

inundated a large portion of the North Platte River and its tributaries in the Hanna Basin. The 

drainage area for Seminoe Reservoir encompasses 7,210 square miles, and its storage capacity 

is approximately 1,017,000 acre-feet of water. The average volume of Seminoe Reservoir 

between 1939 and 2003 was 557,000 acre-feet, with a minimum volume of 56,000 acre-feet in 

Seminoe Road Gas Development Project 3­17
Draft Environmental Impact Statement November 2005

April 1961. In 2000, annual evaporation from Seminoe Reservoir was estimated at 62,800 acrefeet. 

The Wyoming DEQ classifies Seminoe Reservoir as Class 2AB surface water. Average monthly 

discharges from Seminoe Reservoir are shown in Figure 32, Summary of Flow Data. The 

monthly averages shown in this table include data from the full period of record (HydroGeo 

2003a). The U.S. Bureau of Reclamation manages discharges from Seminoe Reservoir to meet 

irrigation demands downstream, to maintain in-stream minimum flows below Kortes Reservoir, 

and to capture the large spring flows due to snowmelt in the North Platte River. The flowmonitoring location for Seminoe Reservoir is shown on Figure 33, Hydrologic Monitoring Sites 

Location Map. 

Water in Seminoe Reservoir is calcium bicarbonate type with slightly alkaline pH. The USGS, the 

Wyoming Game and Fish Department, the EPA, and the Proponent have compiled water quality 

information for the Seminoe Reservoir (USGS 2004, BLM 2001, HydroGeo et al. 2001, HydroGeo 

2001 and 2003a, WRDS 2005). The USGS conducted two days of water quality measurements in 

Seminoe Reservoir in August 1978 (USGS 2004). The Wyoming Game and Fish Department 

conducted annual measurements between 1969 and 1972 (WRDS 2005). The EPA conducted 

measurements in May, August and October 1975 for specific conductivity (WRDS 2005). The 

Proponent’s water quality measurements in Seminoe Reservoir have been ongoing since the 

spring of 2000 (HydroGeo 2003a). 

There are a number of arms in Seminoe Reservoir formed by major tributary drainages that are 

typically inundated. Since these arms are backwater systems with little input from their tributary 

drainages, there is less mixing potential as compared to arms with substantial tributary input such 

as the Medicine Bow arm of the reservoir. Of particular note is the Coal Creek arm, which is a 

popular local fishery, especially in the winter. 

A summary of the water quality data for Seminoe Reservoir is presented in Figure 34, Summary 

of Surface Water Salinity Data. These data were collected at the monitoring locations shown on 

Figure 33, Hydrologic Monitoring Sites Location Map. No seasonal water trends can be 

established from historic data for the Seminoe Reservoir, because existing water quality data are 

highly variable between the different monitoring locations and times. 

3­18  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.4.2.4 Kortes Reservoir

Kortes Reservoir is located about 2 miles below the Seminoe Reservoir dam. Details about Kortes 

Reservoir and dam are set forth in Appendix E, Regional Activity. Kortes Reservoir is a small 

4,700 acre-foot reservoir, whose main purpose is to provide water for power generation. Water 

released from Seminoe Dam to Pathfinder Reservoir passes through the Kortes turbines to 

generate power. Maximum power generation benefits are obtained when Kortes Reservoir 

remains full and the power releases are coordinated with those from the Seminoe power plant. 

Thus, discharges from Kortes Reservoir are generally kept the same as Seminoe Reservoir. 

Wyoming DEQ classifies Kortes Reservoir as Class 2AB surface water. 

Average monthly discharge flows from Kortes Reservoir are the same as from Seminoe Reservoir 

dam as shown in Figure 32, Summary of Flow Data. The monthly averages shown in this table 

include data for the full period of record (HydroGeo 2003b). The flow-monitoring location is shown 

on Figure 33, Hydrologic Monitoring Sites Location Map. No water quality data are available 

for Kortes Reservoir. 

3.4.2.5 Miracle Mile

The Wyoming DEQ classifies the North Platte River below Kortes Reservoir (the stretch known as 

the Miracle Mile) as a blue ribbon fishery and as Class 1 surface water. Class 1 waters are 

surface waters in which no further water quality degradation by point source discharges are 

allowed. 

Flows in the Miracle Mile are determined by discharge from Kortes Reservoir. Senate Bill 2553 

passed by the 90th Congress (1967-1968) mandated operational modification of Kortes Dam to 

provide a minimum stream flow of 500 cubic feet per second (cfs) in the North Platte River 

between Kortes Reservoir and the headwaters of Pathfinder Reservoir. The minimum flow permits 

the maintenance of a fishery in the Miracle Mile stretch of the North Platte River. See Appendix 

E, Regional Activity. Several small tributary streams also contribute water to this stretch of the 

North Platte. 

The USGS and the Proponent compiled baseline water quality information for the Miracle Mile 

(USGS 2004, HydroGeo 2004). A summary of the collected data is presented in Figure 34, 

Summary of Surface Water Salinity Data. These data were collected at monitoring locations 

shown on Figure 33, Hydrologic Monitoring Sites Location Map. 

Seminoe Road Gas Development Project 3­19
Draft Environmental Impact Statement November 2005

The USGS analyzed Miracle Mile from 1969 through 1989 for temperature, specific conductivity, 

dissolved oxygen, and pH. Between 1987 and 1989, the USGS expanded their water quality 

monitoring to include major ions, calcium, magnesium, sodium, chloride, and TDS. The Proponent 

sampled water from the Miracle Mile in May 2003. Based on specific conductivity data, there are 

no definite seasonal trends in the Miracle Mile water quality. Water storage in the Seminoe and 

Kortes reservoirs tends to abate and nullify seasonal water quality variability. Therefore, waters 

released into the Miracle Mile reach of the North Platte River do not exhibit the more definitive 

seasonal water quality variability observed in the North Platte River upstream of the Seminoe 

Reservoir. 

3.4.2.6 Pathfinder Reservoir

The Pathfinder Reservoir is located downstream of the Miracle Mile. The Sweetwater River is a 

tributary of the North Platte River and empties into the Pathfinder Reservoir. Pathfinder Reservoir 

collects water from a 14,600 square mile drainage area and has an estimated storage capacity of 

1,016,000 acre-feet of water. The U.S. Bureau of Reclamation manages discharges from 

Pathfinder Reservoir mainly to meet downstream irrigation demands. During the non-irritation 

season, water is released to satisfy other water rights, enhance fish and wildlife habitat, and 

provide water to operate downstream power plants. 

Wyoming DEQ classifies the Pathfinder Reservoir as Class 2AB surface water. Average 

discharges from Pathfinder Reservoir are shown in Figure 32, Summary of Flow Data. The 

monthly averages shown in this table include data from full period of record (HydroGeo 2003a). 

The flow-monitoring location is shown on Figure 33, Hydrologic Monitoring Sites Location 

Map. 

3.4.2.7 North Platte River Downstream of Pathfinder Reservoir

Flows in the North Platte River between the Pathfinder Dam and the Alcova Reservoir (a stretch 

of approximately 5 miles) are largely determined by discharge from the Pathfinder Reservoir. The 

WDEQ has classified this stretch of the North Platte River as Class 2AB surface water. 

Average, minimum and maximum monthly flows for the North Platte River below Pathfinder 

Reservoir are shown in Figure 32, Summary of Flow Data. The monthly averages shown in this 

figure include data from full period of record (HydroGeo 2003a). Maximum flows generally occur 

in the spring, when natural flows are high; however, high average flows can be and often are 

3­20  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

maintained for irrigation purposes throughout the growing season. This is the first place that 

irrigation occurs form the North Platte River below the Seminoe Reservoir. The flow-monitoring 

location for this stretch of the North Platte River is shown on Figure 33, Hydrologic Monitoring 

Sites Location Map. 

The USGS analyzed water quality for the North Platte River at Alcova Reservoir from 1965 to 

1983 (USGS 2004). A summary of water quality data is presented in Figure 34, Summary of 

Surface Water Salinity Data. No seasonal water quality trends are apparent from the historic 

data. 

3.4.3 Medicine Bow River

The Medicine Bow River is a perennial stream and enters the central portion of Seminoe 

Reservoir from the east. See Figure 30, Platte River Drainage Basin. Wyoming DEQ classifies 

the Medicine Bow River as Class 2AB surface water. The Medicine Bow River inflows into 

Seminoe Reservoir are about 10% to 25% of total North Platte River inflows. The Medicine Bow 

River is outside the EIS analysis area. 

3.4.4 Intermittent Drainages Within the EIS Analysis Area

An “intermittent drainage” means a steam or a reach of a stream that is below the local water 

table for at least some part of the year, and obtains its flow from both surface runoff and ground 

water discharge. O’Brien Creek is the sole intermittent drainage in the EIS analysis area. A 

general summary of the EIS analysis area intermittent drainage characteristics is presented in 

Table 3.4-2, Intermittent Drainage Watershed Characteristics. 

Table 3.4-2, Intermittent Drainage Watershed Characteristics 

Watershed / 

Drainage 

Characteristic 

Subwatershed Area 

(acres) 

Length 

(ft) 

Headwaters 

Elevation 

(ft) 

Discharge 

Elevation 

(ft) 

Average 

Gradient 

(%) 

Discharge 

End Point 

O’Brien Creek Intermittent -- 19,302 58,000 7,400 6,360 1.8 Seminoe 

Reservoir 

3.4.4.1 O’Brien Creek

The Wyoming DEQ classifies O’Brien Creek as Class 3B water, and this intermittent drainage 

does not support fish populations; however other aquatic life, such as macro-invertebrates, can be 

present. 

Seminoe Road Gas Development Project 3­21
Draft Environmental Impact Statement November 2005

The USGS monitored O’Brien Creek in 1967 (WRDS 2005); the BLM in 1979 (WRDS 2005); and 

the Proponent in 2001 and 2002 (HydroGeo 2003a). Measurement locations are shown on Figure 

33, Hydrologic Monitoring Sites Location Map. O’Brien Creek was dry during the 2002 fall 

survey (HydroGeo 2003a), but a flow of 30 gpm was measured in the fall of 2001. The water in 

O’Brien Creek can be classified as sodium sulfate\bicarbonate with a variable TDS concentration 

(961 to 2,720 mg/l), and with moderate alkalinity pH (7.5 -8.3). O’Brien Creek flows into the Coal 

Creek arm of Seminoe Reservoir. 

3.4.5 Ephemeral Drainages Within the EIS Analysis Area

An “ephemeral drainage” means a drainage that flows only in direct response to precipitation in 

the immediate watershed or in response to melting of a cover of snow or ice, and a drainage, 

which has a channel bottom that is nearly always above the local water table. The EIS analysis 

area includes ten main ephemeral drainages that are being considered as potential discharge 

drainages for Seminoe Road Project produced water. The potential discharge drainages are Pool 

Table Draw (East, West, and Main forks), Ayers Draw, Dirtyman Draw, Dry Ditch, Unnamed 

Drainage 1, Longhart Draw, Unnamed Drainage 2, St. Mary’s Ditch, Mountain Lion Draw, and 

Unnamed Drainage 3. See Figure 33, Hydrologic Monitoring Sites Location Map. 

The Wyoming DEQ classifies ephemeral drainages and closed basins in the EIS analysis area as 

Class 3 waters (WDEQ 2001). Class 3 waters are defined as waters that are intermittent, 

ephemeral, or isolated and, because of natural habitat conditions, do not have the potential to 

support fish populations (WDEQ 2001). See Table 3.4-1, Summary of Surface Water Classes 

and Uses. The Wyoming DEQ classifies St. Mary’s Ditch and Pool Table Draw as Class 3B 

waters. These ephemeral drainages do not support fish populations, but other aquatic life, such 

as macro-invertebrates, can be present during certain times of the year when water is flowing in 

the lower reaches of these drainages. 

Ephemeral drainage channels dry out between storm events, which reduce infiltration and 

increases surface runoff along the bottom of the channels. Sediment moves in pulses with these 

storm events resulting in wide channel forms with fine textured bed deposited material. Due to the 

dry soils in these channel bottoms, water predominantly moves as sheet flow or in macropores 

created by preferential erosion and/or animal burrows. Abrupt changes in surface water flows due 

to surface roughness from vegetation (sagebrush, greasewood, and grasses), the channel 

gradient, and/or preferential channels have formed in features like animal trails cause surface 

3­22 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

water to concentrate and velocities to increase. This process can increase the erosive energy of 

the water during storm events. See Figure 35, Hydrologic Process and Geomorphic Cycle 

(Part I). Erosion potential was evaluated during baseline data collection efforts. (See Table 3.4-3, 

Erosion Potential of Proposed Discharge Drainages). 

Flood events are usually short lived since a typical summer thunderstorm lasts less than several 

hours. The majority of the water in these systems moves quickly through the drainage in flash 

floods and storm pulses that are only attenuated based on the travel time of the water. 

Table 3.4-3, Erosion Potential of Proposed Discharge Drainages 

Drainage Drainage 

Type Erosion Potential (1) 

Pool Table Draw Ephemeral Minor 

Ayers Draw Ephemeral Moderate 

Dry Ditch Ephemeral Moderate 

Dirtyman Draw Ephemeral High 

Longhart Draw Ephemeral Moderate 

Unnamed Drainage #2 Ephemeral Moderate 

O'Brien Creek Intermittent Minor 

Unnamed Drainage #1 Ephemeral Moderate 

Mountain Lion Draw Ephemeral High 

St. Mary’s Ditch Ephemeral Moderate to High 

Unnamed Drainage #3 Ephemeral Moderate to High 

Note: 

1. General erosion potential based on observations made 

during the baseline drainage surveys (HydroGeo, 2001, 

2003a, and 2003b). Location of drainages shown on 

Figure 37, Watershed Map. 

Ephemeral channels are susceptible to vertical erosion in the drainage channel bed, called 

“headcuts.” A headcut is an abrupt vertical drop in a channel that is a result of the breakdown of 

soil structure or an increase in flow concentration or velocity. Erosion can continue in the channel 

below a headcut causing a gulley to form, and can cause the channel to be incised deeper than 

before, a process called downcutting. The abrupt change in elevation over the headcut increases 

the erosive energy of the water and can allow the headcut to migrate upstream (See Figures 35 

and 36, Hydrologic Process and Geomorphic Cycle (Parts I and II). Downcutting of the 

drainage channels causes gulley formation and sediment deltas at the mouth of the drainages or 

where the gradient is less (i.e. when water velocity drops). In natural ephemeral drainages, most 

of the erosion activity occurs during storm events or during spring runoff caused by snowmelt. 

The initial causes of headcut and gulley formation are typically the result of changes in water 

discharge timing and amount resulting from improved channel conveyance capacity upstream, the 

Seminoe Road Gas Development Project 3­23
Draft Environmental Impact Statement November 2005

removal of water storage areas such as wetlands or stockponds upstream, less surface 

roughness in the channel, loss of soil structure, and/or changes in the water table. Gulley 

formation is accelerated by the breakdown of soil structures that might normally protect channel 

sides and bottoms; this can result from animal hoof action on soils, animal burrows, changes in 

the water table or grazing by livestock or wildlife. 

During periods of maximum reservoir pool levels, the drainage channels flowing into Seminoe 

Reservoir become inundated further upstream than during low water levels. Sediments 

transported by drainage flows tend to settle where the drainage enters the reservoir pool. As the 

reservoir pool level falls (due to irrigation demands or climatic conditions such as drought), the 

newly deposited sediments again become exposed. As this cycle of inundation and drying repeats 

itself, erosion activity is exacerbated. Previously inundated channels and newly exposed areas are 

extremely susceptible to erosion, and runoff from the drainages can wash out the exposed 

sediments, leading to bank erosion of the drainage channel and headcuts. 

Soil samples were collected at each of the ephemeral drainage being considered for surface 

discharge to measure baseline conditions and to assess the potential geochemical interactions 

that could occur with project produced water (HydroGeo, 2003a). Based on data collected from 

Pool Table Draw, there appear to be seasonal changes in these geochemical interactions, which 

change surface water quality. See Appendix I, Monitoring Results for Seminoe Road Pilot 

Project. 

A general summary of the EIS analysis area potential discharge drainage characteristics is 

presented in Table 3.4-4, Ephemeral Drainage Watershed Characteristics. 

3.4.5.1 Pool Table Draw

Pool Table Draw has two unnamed tributary forks, referred to as the East and West forks of Pool 

Table Draw. The East and West forks merge to form the Main Fork of Pool Table Draw. See also 

Figure 37, Watershed Map, and Table 3.4-4, Ephemeral Drainage Watershed 

Characteristics. 

The drainage channel of the Main Fork of Pool Table Draw is characterized by a low gradient and, 

in places, its natural incision ranges from 3 to 20 feet deep. The channel bottom averages about 1 

to 3 feet across. 

3­24 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Table 3.4-4, Ephemeral Drainage Watershed Characteristics 

Watershed / 

Drainage 

Characteristic 

Subwatershed Area 

(acres) 

Length 

(ft) 

Headwaters 

Elevation 

(ft) 

Discharge 

Elevation 

(ft) 

Average 

Gradient 

(%) 

Discharge 

End Point 

Pool Table 

Draw Ephemeral West Fork 6,572 39,800 7,300 6,420 2.2 

Confluence of 

E. and W. 

Forks 

Pool Table 

Draw Ephemeral East Fork 3,634 27,800 6,670 6,420 0.9 

Confluence of 

E. and W. 

Forks 

Pool Table 

Draw from E&W 

Forks 

Confluence to Ephemeral Main Fork 980 14,400 6,400 6,360 0.4 Seminoe 

Reservoir 

Seminoe 

Reservoir 

Ayers Draw Ephemeral -- 7,229 24,787 6,660 6,360 1.3 Seminoe 

Reservoir 

Dirtyman Draw Ephemeral Main Fork 18,880 48,000 7,200 6,373 1.7 North Platte 

River 

Dry Ditch Ephemeral -- 9,984 35,100 6,760 6,360 1.0 Seminoe 

Reservoir 

Unnamed 

Drainage #1 Ephemeral -- 2,285 8,000 6,580 6,360 2.8 Seminoe Reservoir 

Longhart Draw Ephemeral -- 3,744 16,000 6,720 6,360 2.3 North Platte 

River 

Unnamed 

Drainage #2 Ephemeral -- 2,330 20,000 6,680 6,360 1.5 Seminoe Reservoir 

St. Mary’s Ditch Ephemeral From Project 

Boundary 

3,690 17,500 6,580 6,360 1.3 Seminoe 

Reservoir 

Mt. Lion Draw Ephemeral -- 1,113 11,000 6,550 6,360 1.7 Seminoe 

Reservoir 

Unnamed 

Drainage #3 Ephemeral -- 2,797 14,000 7,000 6,360 4.4 North Platte River 

Pool Table Draw Reservoir is a constructed stock pond located on the West Fork of Pool Table 

Draw, and this stock pond reservoir is fed by Pilot Project produced water. Photos of Pool Table 

Draw and Pool Table Draw Reservoir prior to and during the Pilot Project are shown on Figure 38, 

Pool Table Draw Photographs. 

When Seminoe Reservoir is full, Pool Table Draw flows into the Coal Creek arm of Seminoe 

Reservoir. Under low water conditions in Seminoe Reservoir, Pool Table Draw flows into O’Brien 

Creek, which then flows into Seminoe Reservoir via the Coal Creek arm. See Figure 37, 

Watershed Map. In 2002, given extreme drought conditions, O’Brien Creek was dry, and the Pilot 

Project produced water flowed down Pool Table Draw and into O’Brien Creek before entering into 

Seminoe Reservoir (HydroGeo 2003a). 

Pilot Project produced water has been continuously discharged into the West Fork of Pool Table 

Draw from discharge point DS-2 since December 2001. In May 2002, discharge commenced from 

Seminoe Road Gas Development Project 3­25
Draft Environmental Impact Statement November 2005

DS-3 into the East Fork of Pool Table Draw. Pilot Project produced water from discharge point 

DS-1 was discharged into the West Fork of Pool Table Draw beginning in November 2002. These 

discharges were permitted by Wyoming DEQ Water Quality Division under Permit 37­

WY0041807. See Figure 37, Watershed Map. The average flows from the Pilot Project are about 

1 cfs as shown on Figure 39, Pilot Project Discharge Rates. Continuous flows from the Pilot 

Project have initiated downcutting in the Pool Table Draw, increasing the potential for bank 

erosion during storm events. Given this increased potential for erosion, several storm and runoff 

events have accelerated gulley formation. This erosion is mostly near the confluence with O’Brien 

Creek and the high pool elevation of Seminoe Reservoir. Several small headcuts were also noted 

downstream of the high water mark of Seminoe Reservoir in lake bottom sediments that are 

typically submerged. 

A small headcut (less than 1 foot) in the West Fork of Pool Table Draw has developed as a result 

of the Pilot Project produced water, this headcut area is present near the Conoco pipeline access 

road, and a larger headcut, about 10 feet deep, occurs near the mouth of the drainage at 

Seminoe Reservoir. See Figure 38, Pool Table Draw Photographs. This headcut was noted in 

the baseline survey (HydroGeo et al, 2001) but has eroded and increased in size due, in part, to 

the Pilot Project produced water flow. The Proponent placed riprap at this headcut site in 

November 2002, but these efforts were ineffective in stopping the upstream migration of the 

headcut. 

3.4.5.2 Ayers Draw

Pilot Project-produced water is not currently discharged to this drainage. See also Figure 37, 

Watershed Map, and Table 3.4-4, Ephemeral Drainage Water Characteristics. 

Ayers Draw has several areas of headcutting and ponding at the head of the drainage near a 

stock pond and along the central portion of the drainage (HydroGeo 2003a). The channel in Ayers 

Draw varies from deeply incised zones to broad areas of dispersed flow. The maximum size of the 

incised channel is about 30 feet deep by 5 feet wide. The channel sediments are uniform, 

composed of porous sandy loam soil. An abandoned and a new stock pond are located in the 

upper reaches of Ayers Draw, but both ponds are unnamed. The new pond was full of water at the 

time of the 2001 survey and had a surface area of about 0.5 acres. The new pond was noted as 

being partially full during the 2002 riparian vegetation survey (HydroGeo 2003a). The abandoned 

pond was dry during both 2001 and 2002 surveys (HydroGeo 2003a). 

3­26  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.4.5.3 Dirtyman Draw

The Dirtyman Draw watershed is shown on Figure 37, Watershed Map. Particulars about 

Dirtyman Draw are set forth in Table 3.4-4, Ephemeral Drainage Watershed Characteristics. 

Dirtyman Draw sediments are primarily a sandy loam texture. Headcutting and ponding were 

noted at isolated areas throughout the drainage, particularly in the lower reaches (HydroGeo 

2003a). The upper portion of the drainage is a low gradient overland flow area with little 

headcutting and no ponding. The middle portion of the drainage has minor headcutting and the 

flow channel varies from moderately incised to overland flow. The drainage is deeply incised in the 

lower portions of the drainage with sections over 25 feet deep and 10 feet wide. Several areas of 

ponding occur in the lower reach of the drainage. These ponded areas were flooded in the spring 

of 2001 due to snowmelt, but were dry at the time of the 2002 survey. 

Two small stock ponds are located in the upper reaches of Dirtyman Draw, one stock pond area is 

located in the middle portion of the drainage, and another occurs in the lower reaches. The stock 

ponds in the upper and middle reaches of the drainage were dry at the time of the 2001 and 2002 

surveys. The stock pond area in the lower reaches of Dirtyman Draw was dry at the time of both 

the 2001 and 2002 surveys, but water was present in 2003 (HydroGeo, 2003a). An off channel 

storage basin is located adjacent to the lower stock pond. Water was present in the storage basin 

during the 2001 survey, but the basin was dry in 2002 and in 2003 (HydroGeo, 2003a). 

3.4.5.4 Dry Ditch

Dry Ditch drains the east side of the EIS analysis area. See Figure 37, Watershed Map. 

Particulars about Dry Ditch are set forth in Table 3.4-4, Ephemeral Drainage Watershed 

Characteristics. 

Dry Ditch sediments range from a sandy loam to a clay loam texture. Headcutting and ponding 

were noted at dispersed areas throughout the drainage, particularly in the upper and middle 

reaches (HydroGeo 2003a). The channel is deeply incised in the upper and middle portion of the 

drainage reaching over 20 feet deep and 10 feet wide. Isolated areas of ponding associated with 

headcuts were found throughout the drainage. All ponded areas were dry during the 2002 field 

survey (HydroGeo 2003a). 

Seminoe Road Gas Development Project 3­27
Draft Environmental Impact Statement November 2005

Three stock ponds occur in Dry Ditch, and these are identified as Pond #1, Pond #2, and Pond #3 

located in the upper, middle, and lower portions of the drainage, respectively. All three ponds were 

dry during the surveys (HydroGeo 2003a), but they showed signs of having been flooded. These 

signs included hydric soils, well-defined shoreline marks, mud cracks, and hydrophytic vegetation. 

Shallow wells are located below the upper and middle stock ponds. Pond #1 is approximately one 

acre in size, Pond #2 is approximately 4 acres in size, and Pond #3 has an area of 2.5 acres. 

Hydric soils and hydrophytic vegetation were present downstream of these ponds. 

Two sediment samples were collected from Dry Ditch in September 2002. One sample was 

collected at Pond #2 in the middle part of the drainage, and the second sample was collected 

toward the bottom of the drainage near the road crossing. The sediment sample from the pond 

was a dry sandy clay loam material. 

3.4.5.5 Unnamed Drainage #1

The Unnamed Drainage #1 is shown on Figure 37, Watershed Map, and details about this 

drainage are set forth in Table 3.4-4, Ephemeral Drainage Watershed Characteristics. 

3.4.5.6 Longhart Draw

Longhart Draw is shown on Figure 37, Watershed Map, and details about this drainage are set 

forth in Table 3.4-4, Ephemeral Drainage Watershed Characteristics. 

3.4.5.7 Unnamed Drainage #2

Unnamed Drainage #2 is shown on Figure 37, Watershed Map, and details about this drainage 

are set forth in Table 3.4-4, Ephemeral Drainage Watershed Characteristics. 

3.4.5.8 St. Mary’s Ditch

St. Mary’s Ditch drains the east side of the EIS analysis area south of the North Platte River. This 

drainage is shown on Figure 37, Watershed Map, and details about this drainage are set forth in 

Table 3.4-4, Ephemeral Drainage Watershed Characteristics. 

St. Mary’s Ditch several large headcut areas and associated ponding areas were dispersed 

throughout the middle portion of the drainage (HydroGeo 2003a). The channel is deeply incised 

more than 10 feet deep and 15 feet wide in the middle portion of the drainage. The channel 

sediments range from a sandy loam to a clay loam texture. 

3­28  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

One stock pond, referred to as St. Mary’s Spring, is located off channel but adjacent to St. Mary’s 

Ditch. The spring was flowing and the pond was full at the time of the 2002 and 2003 surveys 

(HydroGeo, 2003a). The stock pond and spring area together encompass an area of 

approximately 0.5 acre in size. 

3.4.5.9 Mountain Lion Draw

Mountain Lion Draw drains the north central side of the EIS analysis area south of the North Platte 

River. See Figure 37, Watershed Map. Particulars about this drainage are set forth in Table 3.4­

4, Ephemeral Drainage Watershed Characteristics. 

Mountain Lion Draw has several small to medium headcut areas and associated minor ponding 

areas were dispersed throughout the upper portion of the drainage (HydroGeo 2003a). The 

channel is deeply incised more than 10 feet deep and 15 feet wide in the middle and lower portion 

of the drainage. The channel sediment ranges from a sandy loam to a clay loam texture in the 

upper reaches, within a very sandy texture in the middle and lower reaches. 

3.4.5.10 Unnamed Drainage #3

Unnamed Drainage #3 is shown on Figure 37, Watershed Map, and details about this drainage 

are set forth in Table 3.4-4, Ephemeral Drainage Watershed Characteristics. 

3.4.6 Playas Within the EIS Analysis Area

Three closed playa basins (Ferris Lake, Alkali Flats, and St. Mary’s Anticline Basin) are located in 

the EIS analysis area south of Seminoe Reservoir. See Figure 37, Watershed Map. 

Particulars about the three playas are presented in Table 3.4-5, Playa Characteristics 

Summary. 

Table 3.4-5, Playa Characteristics Summary 

Watershed / Drainage Characteristic 

Contributing 

Area (acres) 

Natural Extent 

(acres) 

Ferris Lake Ephemeral (Closed Basin) 4,491 20-25 

Alkali Flats Ephemeral (Closed Basin) 12,094 50-60 

St. Mary’s Anticline Basin Ephemeral (Closed Basin) 11,002 10-50 

Seminoe Road Gas Development Project 3­29
Draft Environmental Impact Statement November 2005

3.4.6.1 Ferris Lake

The Ferris Lake playa is a broad, flat, sparsely vegetated area about 20 to 25 acres in size. 

Drainage into the Ferris Lake occurs primarily by overland flow with poorly defined channels. 

However, occasional channels do occur intermittently in higher gradient portions of the area. No 

headcuts or other erosional features have been observed in these channels (HydroGeo, 2003a). 

3.4.6.2 Alkali Flats

Taylor Draw drains into Alkali Flats and has poorly defined channels. However, some channeling 

occurs intermittently in higher gradient portions of the watershed. The Alkali Flats playa covers a 

broad area of approximately 1,000 acres, with a barren lake bottom zone of approximately 50 to 

60 acres in size. 

A soil sample was collected near the center of Alkali Flats. The sediment was a dry clay loam 

material with a high concentration of salts and trace metals. The soil sample results were typical 

of evaporative basins (HydroGeo 2003a) and were as follows: aluminum (47,800 mg/kg), iron 

(29,500 mg/kg), manganese (373.9 mg/kg), zinc (105.9 mg/kg), arsenic (7.7 mg/kg), chromium 

(42.0 mg/kg), copper (24.2 mg/kg), nickel (24.5 mg/kg), mercury (7.5 mg/kg), and lead (24.0 

mg/kg). The soil pH was neutral at 7.5 units. The EC, SAR and alkalinity were 1.5 mmhos/cm, 

15.89 (unitless), and 250.1 mg/kg, respectively. 

3.4.6.3 St Mary’s Anticline Basin

The St. Mary’s Anticline playa is a broad, flat, sparsely vegetated area about 50 acres in size, with 

a barren lake bottom of approximately 10 acres. Two unnamed drainages enter this basin. 

3.5 Ground Water

3.5.1 Hanna Basin

The Seminoe Road Project is located within the Hanna Basin, which is a deep closed geologic 

basin containing sedimentary rock that extends to a depth over 30,000 feet. The Hanna Basin 

covers an area of approximately 1,750 square miles (1.1 million acres). The aerial extent of the 

Hanna Basin and its relation to the EIS analysis area and Pilot Project are shown on Figure 31, 

Hanna Basin. Additional geologic discussion is presented in Section 3.3, Geology. 

3­30  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

The ground water-bearing zones in the Hanna Basin include both shallow and deep bedrock 

ground water systems. Minor ground water resources are also present in the surficial 

unconsolidated and alluvial sediments within the region’s drainages. 

Recharge to the ground water system occurs by infiltration of precipitation into the shallow 

sediments or bedrock exposed at the surface, typically on the edges of the Hanna Basin. Ground 

water recharge from precipitation is estimated to range between 5 to 10% of the average annual 

precipitation (Lowham et al. 1985). A small amount of ground water recharge also comes from 

infiltration along losing reaches of streams, ponds, and lakes. Recharge to the deep ground water 

system is at a much lower rate. 

Shallow ground water zones generally discharge to the surface as springs and seeps and 

underflow into local streams and rivers. It is possible that some ground water also exits the Basin 

along marginal faults and fracture systems. Deep ground water is believed to be very old, 

relatively stagnant, and effectively not connected to surface water. Deep basin ground water 

generally flows from the edges toward the center of the Hanna Basin. See Figure 31, Hanna 

Basin. 

3.5.2 Hanna Basin Bedrock Ground Water Systems in the EIS Analysis

Area

This section focuses on the ground water systems that could be directly affected by operations of 

the Seminoe Road Project. The discussion starts with the deepest (oldest) bedrock formations in 

the Mesaverde Group and concludes with the shallowest (youngest) bedrock formations of the 

Fox Hills Sandstone\Medicine Bow Formation. See Figure 29, General Stratigraphic Column 

and Geologic Cross Section A-A’. 

3.5.2.1 Mesaverde Group (Deep ground water bearing formations)

The Mesaverde Group is approximately 4,000 feet thick in the EIS analysis area and is composed 

of sandstone, shale, and coalbeds of the Haystack Mountain, Allen Ridge, Pine Ridge, and 

Almond formations. The Seminoe Road Project would develop and produce natural gas from 

coalbeds in the Allen Ridge and Almond formations. 

Ground water is known to occur in the sandstone and coalbeds in the Mesaverde strata. The 

water-bearing strata of the Mesaverde formations are unconfined near the fringes of the Hanna 

Seminoe Road Gas Development Project 3­31
Draft Environmental Impact Statement November 2005

Basin and become confined toward the center of the Hanna Basin as the Mesaverde formations 

dip beneath the overlying Lewis Shale. See Figure 29, General Stratigraphic Column and 

Geologic Cross Section A-A’. Mesaverde water-bearing zones are not considered major 

aquifers in the EIS analysis area; however, a few low yield stock wells are completed in the 

Mesaverde strata on the flanks of the Haystack Mountains to the west and southwest of the EIS 

analysis area. No known domestic water wells are installed in this area, but several springs do 

issue from the Mesaverde strata in this area. See Figure 33, Hydrologic Monitoring Sites 

Location Map. 

The Proponent has installed 16 coalbed natural gas test wells as part of their Pilot Project. These 

wells are installed in the Almond and Allen Ridge formations of the Mesaverde Group strata at a 

depth of about 5,000 feet below the surface. The wells produce about 35 gpm and have generally 

good water quality, suitable for domestic or stock watering purposes. The water from these wells 

do not meet secondary domestic drinking water criteria for TDS (limit of 500 mg/l) or agricultural 

water quality criteria because of high SAR (agricultural limit of 8.0). Secondary domestic water 

quality limits are based on aesthetic criteria and not human health. 

The Pilot Project produced water is sodium bicarbonate type with slightly alkaline pH (8.1 to 8.6) 

and moderate concentrations of TDS (600 to 1,200 mg/l). The produced water has low 

concentrations of trace constituents and moderately SAR ranging from 20 to 40. Passive aeration 

and filtration has been used to treat Pilot Project produced water to meet NPDES permit 

limitations prior to surface discharge to Pool Table Draw. Produced water quality has improved 

since the Pilot Project began pumping water in 2004. See Figure 40, Pilot Project Water 

Quality. 

A water sample from Pilot Project well 4-35 was age-dated using carbon 14, tritium, and oxygen 

18/16 stable isotope methods. The results of the analyses indicated that the water is over 5,000 

years old. The antiquity of the ground water demonstrates that the deep Mesaverde ground water 

system is stagnant with little or no connectivity with shallow ground water-bearing zones or area 

surface water resources (BLM 2001). 

3.5.2.2 Lewis Shale

The Lewis Shale is approximately 2,500 feet thick in the EIS analysis area and is composed 

primarily of shale with some interbedded sandstone layers (USGS 1978). The Lewis Shale as a 

3­32 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

whole has a very low permeability and acts as a confining unit that hydraulically separates the 

underlying Mesaverde Group rocks from younger Fox Hills Sandstone and Medicine Bow 

Formation strata (HydroGeo 2003b). 

The Dad Sandstone is a member of the Lewis Shale and is thought to be a laterally extensive 

water-bearing unit; however; little information is available regarding the hydraulic properties or 

water quality of the Dad Sandstone because it is not considered a viable aquifer or a natural gas 

bearing zone. 

The Dad Sandstone is being considered as a injection horizon for Project produced water under 

Alternative D (See Section 2.6, Underground Injection of Produced Water, Alternative D). There 

are no known water wells installed in the Dad Sandstone within the EIS analysis area. 

3.5.2.3 Fox Hills Sandstone\Medicine Bow Formation (Shallow Ground Water

Bearing Formations)

The Fox Hills Sandstone is about 970 feet thick in the EIS analysis area. It is composed of 

interbedded sandstone, shale and coal units. The Fox Hills Sandstone has moderate to good 

permeability and is considered an aquifer that yields ground water to wells where the formation 

occurs near the surface. 

The Medicine Bow Formation is about 4,500 feet thick in the EIS analysis area. Medicine Bow 

Formation strata consist of sandstone, shale and coal units. The lower portion of the formation is 

composed of massive bedded to cross-bedded brown sandstone with numerous coalbeds. The 

Seminoe Road Project would develop and produce natural gas from coalbeds of the lower 

Medicine Bow Formation. Locally, the formation exhibits moderate permeability and can be 

considered an aquifer, but intervening shale beds limit the formation ability to transmit ground 

water vertically (USGS 1978). 

Several wells are completed in the Fox Hills Sandstone\Medicine Bow Formation ground waterbearing strata and several springs issue from this system. Water from these wells and springs are 

utilized for livestock and wildlife watering. No known domestic water wells are installed in these 

strata within the EIS analysis area. 

In addition to the Fox Hills Sandstone\Medicine Bow Formation, several other shallow ground 

water-bearing formations are present in the EIS analysis area including the Hanna and Ferris 

Seminoe Road Gas Development Project 3­33
Draft Environmental Impact Statement November 2005

formations, which overly the Medicine Bow Formation. Water-bearing zones in these formations 

have limited hydraulic connectivity and exist under both unconfined and semi-confined conditions. 

Several wells are completed in these zones, and a few springs issue from this system. Water from 

these wells and springs are primarily utilized for livestock and wildlife watering; however; the ID 

Ranch domestic well is believed to be installed in this formation. See Figure 33, Hydrologic 

Monitoring Sites Location Map. No other known domestic water wells are installed in these 

strata within or surrounding the EIS analysis area. 

3.5.3 Hanna Basin Alluvial Ground Water Systems

Ground water exists in the alluvial sediments along the North Platte River and the terrace deposits 

surrounding Seminoe Reservoir. These zones are generally unconfined. These water-bearing 

sediments are locally considered an aquifer and contain shallow water wells. Several domestic 

wells in the area (Boat Club and Sheller) are completed in alluvial sediments (Hydro Geo 2003a). 

See Figure 33, Hydrologic Monitoring Sites Location Map. 

Limited ground water resources also exist in the surficial unconsolidated and alluvial sediments 

within and adjacent to the area’s ephemeral drainages where ground water presence is generally 

seasonal, the result of precipitation and snowmelt events; however, no know wells are installed in 

the shallow sediments along ephemeral drainages within the EIS analysis area. 

3.5.4 Springs Within and Adjacent to the EIS Analysis Area

The primary springs in the area are part of the baseline monitoring for the Seminoe Road Project. 

A summary of the spring monitoring sites is presented in Table 3.5-1, Spring Information. A 

complete listing of the spring water quality data is presented in HydroGeo (2003a). Spring flow 

and water quality generally shows large ranges of natural\seasonal variability because they are 

recharged from nearby surface areas. 

3.5.4.1 O’Brien Spring

O’Brien Spring was monitored in May 2000, May 2001, September 2001, and September 2002 

(HydroGeo 2003a). The spring flows at a rate of about 30 to 60 gpm and issues from faulted 

Mesaverde bedrock. The water at this site is good quality meeting domestic, agricultural and 

livestock water criteria and is classified as sodium/calcium bicarbonate/sulfate type, with a 

moderate TDS concentration (728 to 767 mg/l), slightly alkaline pH (8.0 to 8.4), and low 

3­34 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Table 3.5-1, Spring Information 

Spring Location(1) Flow Rate 

(gpm) 

Total 

Dissolved 

Solids 

(mg/l) 

pH Occurrence 

O’Brien 

NE 1⁄4 SW 1⁄4 

Section 9 

T25N R85W 

30 to 60 728 – 767 8.0 – 8.4 

Mesaverde 

sandstone bedrock 

fault 

Corral Creek 

NE 1⁄4 SE 1⁄4 

Section 27 

T24N R86W 

<1 608 – 990 7.0 – 8.4 Mesaverde shallow 

bedrock or alluvium 

Ayers 

SW 1⁄4 NE 1⁄4 

Section 19 

T24N R84W 

<1 to Dry 19,400 8.3 

Medicine Bow 

shallow bedrock or 

alluvium 

Miller Bend 

SE 1⁄4 SE 1⁄4 

Section 12 

T22N R86W 

<1 10,852 8.1 Mesaverde fractured 

bedrock 

Alkali Flat #1 

SW 1⁄4 SW 1⁄4 

Section 12 

T21N R84W 

32 1,464 7.9 

Medicine Bow 

shallow bedrock or 

alluvium 

Alkali Flat #2 

SE 1⁄4 NW 1⁄4 

Section 3 

T22N R84W 

<1 3,517 8.0 

Medicine Bow 

shallow bedrock or 

alluvium 

St. Mary’s 

SE 1⁄4 NE 1⁄4 

Section 12 

T22N R84W 

3 2,430 8.0 

Ferris Formation 

shallow bedrock 

fracture 

Note: 

1. Spring locations are shown on Figure 33, Hydrologic Monitoring Sites Location Map. 

concentrations of trace constituents with the exception of total manganese (66 to 266 μg/l) and 

sulfate (241 to 275 mg/l). 

3.5.4.2 Corral Creek Spring

Corral Creek Spring was monitored in June 2000, May 2001, September 2001, and September 

2002 (HydroGeo 2003a). The spring flows at a rate of less than one gpm and issues from shallow 

Mesaverde bedrock or alluvium. Corral Creek Spring water is poor quality and does not meet 

domestic water quality criteria. It is classified as a sodium bicarbonate type with moderate TDS 

concentrations (608 to 990 mg/l) and neutral to slightly alkaline pH (7.0 to 8.4). The water from 

this spring has low concentrations of trace constituents with the exception of elevated 

concentrations of aluminum (164 μg/l), total iron (72 to 4,900 μg/l), and total manganese (140 to 

200 μg/l). 

3.5.4.3 Ayers Draw Spring

Ayers Spring was monitored in September 2001 and September 2002 (HydroGeo 2001 and 

2003a). The spring was not flowing in 2002 and a laboratory sample was not collected, but field 

water quality measurements were taken from a small stagnant pond below the spring. This spring 

Seminoe Road Gas Development Project 3­35
Draft Environmental Impact Statement November 2005

issues from shallow Medicine Bow bedrock or alluvium. The spring is very poor quality and does 

not meet domestic, agricultural, or livestock standards. The pH of the spring water was slightly 

alkaline (8.3), the EC was >20,000 μmhos/cm, and the temperature was 68.2° F. In 2001, a water 

quality sample from Ayers Creek Spring indicated that it was sodium sulfate type. The water was 

highly saline with high concentrations of many trace constituents including sodium (4,200 mg/l), 

sulfate (9,400 mg/l), chloride (698 mg/l), TDS (19,400 mg/l), dissolved manganese (268 μg/l), and 

SAR (36 unitless) (HydroGeo 2003a). 

3.5.4.4 Miller Bend Spring

Miller Bend Spring was monitored in September 2002 (HydroGeo 2003a). The spring was flowing 

at a rate of less than one gpm and issues from fractured shallow Mesaverde bedrock. Miller Bend 

Spring water is poor quality and does not meet water quality criteria for domestic, agricultural, or 

livestock. It is classified as a sodium sulfate type with a slightly alkaline pH (8.1) and a high 

concentration of TDS (10,852 mg/l). The water from this spring has low concentrations of trace 

constituents with the exception of elevated concentrations of sulfate (6,940 mg/l), total iron (1,803 

μg/l), total manganese (161.5 μg/l), and SAR (10.8 unitless). This spring was located outside the 

2000 and 2001 survey areas and was not sampled during those years. 

3.5.4.5 Alkali Flat Spring #1

Alkali Flat Spring #1 was monitored in September 2002 (HydroGeo 2003a). This is a developed 

spring with a solar powered pump and stock tank. Flow into the stock tank was measured as 32 

gpm. This spring issues from shallow Medicine Bow bedrock or alluvium. Alkali Flat Spring #1 

water is of moderate quality and meets water quality criteria for agriculture and livestock, but not 

for domestic purposes. It is classified as a sodium sulfate type with slightly alkaline pH (7.9) and 

moderate TDS concentration (1,464 mg/l). The water from this spring has low concentrations of 

trace constituents with the exception of elevated concentrations of sulfate (911 mg/l), total iron 

(1,248 μg/l), and total manganese (156.9 μg/l). This spring was located outside the 2000 and 

2001 survey areas and was not sampled during those years. 

3.5.4.6 Alkali Flat Spring #2

Alkali Flat Spring #2 was monitored in September 2002 (HydroGeo 2003a). Flow from this small is 

less than one gpm, into a small pond, and the water has a foul odor. This spring issues from 

shallow Mesaverde bedrock or alluvium. Alkali Flat Spring #2 is poor quality and only meets 

livestock water quality criteria. The water is sodium sulfate type with a slightly alkaline pH (8.0) 

3­36  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

and a high TDS concentration (3,517 mg/l). The water from this spring has low concentrations of 

trace constituents with the exception of elevated concentrations of sulfate (1,988 mg/l), aluminum 

(850 μg/l), total iron (5,430 μg/l), total manganese (330.6 μg/l), and SAR (18.4 unitless). This 

spring was located outside the 2000 and 2001 survey areas and was not sampled. 

3.5.4.7 St. Mary’s Spring

St. Mary’s Spring was monitored in September 2002 (HydroGeo 2003a). This spring flow is about 

3 gpm into a small stock pond and issues from a fractured Ferris Formation sandstone bed. St. 

Mary’s Spring water is poor quality meeting only livestock water quality criteria. The water is 

sodium sulfate type with a slightly alkaline pH (8.0) and a high TDS concentration (2,430 mg/l). 

The water from this spring has low concentrations of trace constituents with the exception of 

elevated concentrations of sulfate (1,452 mg/l), aluminum (434 μg/l), total iron (5,040 μg/l), and 

total manganese (609.7 μg/l). This spring was located outside the 2000 and 2001 survey areas 

and was not sampled. 

3.5.5 Stock Wells Within and Adjacent to the EIS Analysis Area

The primary stock wells in the area are part of the baseline monitoring for the Seminoe Road 

Project. Well producing zones were projected based on preliminary geologic mapping of the area 

and estimated well depth; in many cases well completion information was not available. Shallow 

well levels and water quality generally shows large ranges of natural\seasonal variability because 

they are recharged from nearby surface sources. A summary of the well monitoring sites is 

presented in Table 3.5-2, Well Information. A complete listing of the well water quality data is 

presented in HydroGeo (2003a). 

3.5.5.1 Section 19 Well

The Section 19 Well was monitored in May 2000, June 2000, May 2001, September 2001, and 

September 2002 (HydroGeo 2003a). This well is artesian, and flows are diverted to a stock tank 

one-half mile to the east. This well is believed to be completed in the Mesaverde strata. The water 

at this site is poor quality only suitable for livestock but not for domestic or agricultural purposes. 

The water at this site is calcium sulfate/bicarbonate type with a slightly alkaline pH (7.2 to 7.8) and 

a moderate TDS concentration (842 to 969 mg/l). The water has low concentrations of trace 

constituents, with the exception of high concentrations of sulfate (220 to 411 mg/l), and total iron 

(230 to 2,800 μg/l). Flow from the well is about 2 gpm. 

Seminoe Road Gas Development Project 3­37
Draft Environmental Impact Statement November 2005

Table 3.5-2, Well Information 

Well Location (1) Type of 

Well 

Well 

Depth 

(fee) 

Water Level 

Below 

Surface 

(feet or 

Flow Rate 

(gpm) 

Total 

Dissolved 

Solids 

(mg/l) 

pH 

Projected 

Producing 

Interval 

Section 19 

SW 1⁄4 NW 1⁄4 

Section 19 

T23 N R85W 

Stock 

watering 

NA 2 gpm 842 – 969 7.2 – 7.8 Mesaverde 

Miller #1 

NW 1⁄4 NE 1⁄4 

Section 33 

T23N R85W 

Stock 

watering 

246 2 gpm 775 – 860 8.2 – 8.7 Medicine Bow 

Little Shoe 

NE 1⁄4 NW 1⁄4 

Section 1 

T23N R86W 

Stock 

watering 

520 23–24.5 ft 1,150 – 1,720 7.9 – 8.2 Mesaverde 

Dry Ditch 

#1 

NW 1⁄4 NE 1⁄4 

Section 7 

T23N R84W 

Stock 

watering 

NA 30 ft 1,372 7.8 Medicine Bow 

Dry Ditch 

#2 

SE 1⁄4 NW 1⁄4 

Section 11NA 

T23N R85W 

Stock 

watering 

NA 6 ft 2,574 7.9 Medicine Bow 

Alkali Flat 

SW 1⁄4 NE 1⁄4 

Section 23 

T22N R84W 

Stock 

watering 

NA 34 ft 4,372 7.9 Mesaverde 

ID Ranch 

NE 1⁄4 SW 1⁄4 

Section 29 

T24N R84W 

Domestic 

use NA NA 497 – 1,720 7.7 – 8.3 Medicine Bow 

Seminoe 

Boat Club 

(winter) 

NW 1⁄4 NW 1⁄4 

Section 9 

T24N R84W 

Domestic 

use 287 16 ft 1,130 – 1,360 8.0 – 8.2 

Medicine Bow or 

Seminoe 

Reservoir 

Alluvium 

Sheller 

SE 1⁄4 NE 1⁄4 

Section 18 

T22N R85W 

Domestic 

use 55 9 ft 329 7.1 North Fork Alluvium 

Note: 

1. Water well locations are shown on Figure 33, Hydrologic Monitoring Sites Location Map. 

3.5.5.2 Miller #1 Well

The Miller #1 well was monitored in May 2001, September 2001, and September 2002 (HydroGeo 

2003a). This well is artesian, and its flow is diverted to a stock tank next to the well. This well is 

believed to be complete in the Medicine Bow Formation. The water at this site is poor quality and 

only meets livestock water quality criteria. It is unsuitable for domestic or agricultural purposes. 

The water is sodium bicarbonate type with a moderately alkaline pH (8.2 to 8.7) and a moderate 

TDS concentration (775 to 860 mg/l). The water has low concentrations of trace constituents and 

has a high value of SAR (22.0 to 26.8). Flow into the stock tank is about 2 gpm. 

3­38  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.5.5.3 Little Shoe Well

The Little Shoe Well was monitored in May 2001, September 2001, and September 2002 

(HydroGeo 2003a). The water level in this well is between 23 to 24.5 feet below surface. This well 

is believed to be complete in the Mesaverde strata. The water at this site is poor quality and is 

only suitable for livestock watering. It does not meet domestic or agricultural standards. The water 

is sodium sulfate type with a slightly alkaline pH (7.9 to 8.2) and a high TDS concentration (1,150 

to 1,720 mg/l). The water has moderate concentrations of trace constituents including sulfate (497 

to 945 mg/l), total aluminum (<50 to 291 μg/l), total iron (381 to 16,200 μg/l), total manganese (62 

to 166 μg/l), and a high value of SAR (7.1 to 11.1). 

3.5.5.4 Dry Ditch Well #1

The Dry Ditch #1 well was monitored in September 2002 (HydroGeo 2003a). The water level in 

this well was about 30 feet below surface. This well is believed to be complete in the Medicine 

Bow Formation. The water at this site is poor quality and is only suitable for livestock watering. 

Water quality does not meet domestic or agricultural water quality criteria. The water is sodium 

sulfate type with a slightly alkaline pH (7.8) and a high TDS concentration (1,372 mg/l). The water 

has moderate concentrations of trace constituents including sulfate (827 mg/l), total aluminum 

(365 μg/l), total iron (3,363 μg/l), total manganese (62 μg/l), and SAR (12.4). This well is located 

outside the 2000 and 2001 survey areas and was not monitored during those years. 

3.5.5.5 Dry Ditch Well #2

The Dry Ditch #2 well was monitored in September 2002 (HydroGeo 2003a). The water level in 

this well was about six feet below surface. This well is believed to be complete in the Medicine 

Bow Formation. The water at this site is sodium sulfate type with a slightly alkaline pH (7.9) and a 

high TDS concentration (2,574 mg/l). The water has high concentrations of trace constituents 

including sulfate (1,451 mg/l), total aluminum (786.5 μg/l), total iron (5910 μg/l), and total 

manganese (261 μg/l). This well was located outside the 2000 and 2001 survey areas and was 

not monitored during those years. 

3.5.5.6 Alkali Flat Well

The Alkali Flat Well was monitored in September 2002 (HydroGeo 2003a). The water level in this 

well was about 34 feet below surface. This well is believed to be complete in the Mesaverde 

strata. The water at this site is poor quality and only meets livestock water quality criteria. It is not 

Seminoe Road Gas Development Project 3­39
Draft Environmental Impact Statement November 2005

suitable for domestic or agricultural purposes. The water is sodium sulfate type with a slightly 

alkaline pH (7.9) and a high TDS concentration (4,372 mg/l). The water has high concentrations of 

trace constituents including sulfate (2,751 mg/l), total iron (791 μg/l), total manganese (453 μg/l), 

and SAR (11.8). This well was located outside the 2000 and 2001 survey areas and was not 

monitored during those years. 

3.5.6 Domestic Wells Within and Adjacent to the EIS Analysis Area

Three domestic water wells were identified and monitored for the Seminoe Road Project (ID 

Ranch, Seminoe Boat Club (Winter), and Sheller domestic wells). See Figure 33, Hydrologic 

Monitoring Sites Location Map. Two additional domestic wells in the Dugway home site area 

were located but have been abandoned (HydroGeo 2003a). The general producing zones of these 

wells were projected based on preliminary geologic mapping of the area and estimated well depth; 

well completion information was not available for these wells. Shallow well levels and water quality 

generally shows large ranges of natural\seasonal variability because they are recharged from 

nearby surface sources. A summary of the well monitoring sites is presented in Table 3.5-2, Well 

Information. A complete listing of the well water quality data is presented in HydroGeo (2003a). 

3.5.6.1 ID Ranch Well

The ID Ranch Well was monitored in May 2000, May 2001, September 2001, and September 

2002 (HydroGeo 2003a). The water level in this well was not measured because the wellhead was 

sealed, though it is reported to be shallow. The water at this site does not meet secondary 

domestic drinking water criteria for TDS (limit of 500 mg/l). Secondary domestic water quality 

limits are based on aesthetic criteria and not human health. Water from this well is calcium 

bicarbonate type with a slightly alkaline pH (7.7 to 8.3) and a high TDS concentration (497 to 1720 

mg/l). The water has low concentrations of trace constituents. 

3.5.6.2 Boat Club “Winter” Well

The Boat Club “Winter” Well was sampled in May 2001, September 2001, and September 2002 

(HydroGeo 2003a). The water level was not measured because the wellhead was sealed. This 

well is completed in the Medicine Bow Formation. The water at this site does not meet secondary 

domestic drinking water criteria for TDS (limit of 500 mg/l) or sulfate (250 mg/l). Secondary 

domestic water quality limits are based on aesthetic criteria and not human health. The water is 

sodium sulfate type with a slightly alkaline pH (8.0 to 8.2) and has high TDS concentrations (1,130 

3­40  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

to 1,360 mg/l). The water has low concentrations of trace constituents with the exception of 

moderately high concentrations of sulfate (482 to 657 mg/l). 

3.5.6.3 Sheller Well

The Sheller Well was sampled in September 2002 (HydroGeo 2003a). The water level in the well 

was 9 feet below surface. This well is completed in the North Platte River alluvium. The well water 

does not meet secondary domestic drinking water criteria for iron (300 μg/l), manganese (50 μg/l), 

and zinc (500 μg/l). Secondary domestic water quality limits are based on aesthetic criteria and 

not human health. The water is sodium chloride\bicarbonate type with a neutral pH (7.1) and a low 

TDS concentration (329 mg/l). The water has low concentrations of trace constituents with the 

exception of high concentrations of total iron (6,530 μg/l), total manganese (265 μg/l), and total 

zinc (2,288 μg/l). This well was located outside the 2000 and 2001 survey areas and was not 

monitored during those years. 

3.6 Vegetation

3.6.1 Vegetation Communities

Fourteen upland vegetation types were mapped within the EIS analysis area. See Figure 44, 

Vegetation Map. The acreage of each vegetation community within the EIS analysis area is 

presented in Table 3.6-1, Vegetation Communities. 

Aerial photos obtained from the Proponent were used to map vegetation. This “office” mapping 

was followed by a 2003 field reconnaissance survey to corroborate the vegetation delineations 

made from examination of aerial photos. 

3.6.1.1 Wyoming Sagebrush/Mixed Grass

This vegetation community occurs over broad expanses in the EIS analysis area on level to gently 

rolling uplands and alluvial plains. 

Wyoming sagebrush (Artemisia var. tridentata wyomingensis) dominates this community with an 

understory composed of a variety of grass species including Sandberg bluegrass (Poa secunda), 

threadleaf sedge (Carex filifolia), green needlegrass (Nassella viridula), Indian ricegrass 

(Achnatherum hymenoides), thickspike wheatgrass (Elymus lanceolatus) and western wheatgrass 

(Pascopyrum smithii). Sandberg bluegrass is the most common grass species. Needle-andthread (Hesperostipa comata var. comata) dominates on more sandy soils to the general 

Seminoe Road Gas Development Project 3­41
Draft Environmental Impact Statement November 2005

exclusion of most other grass species. Plant cover typically ranges from 25 to 40%, although 

cover values up to 50% may be found. 

Table 3.6-1, Vegetation Communities 

Vegetation Community1 Area2 

(acres) 

Portion of EIS 

Analysis Area 

(%) 

Reclamation 

Potential 

Wyoming Sagebrush/Mixed Grass 29,320 21.4 Moderate 

Wyoming Sagebrush/Threadleaf Sedge 29,230 21.3 Moderate 

Wyoming Sagebrush/Green Rabbitbrush 1,910 1.4 Moderate 

Low Shrub/Mixed Grass 34,010 24.9 Low to Moderate 

Mixed Sagebrush 3,250 2.4 Low to Moderate 

Mixed Shrub 12,180 8.9 Low to Moderate 

Mixed Grass 3,120 2.3 Moderate 

Threadleaf Sedge/Mixed Grass 1,260 0.9 Moderate 

Basin Big Sagebrush/Greasewood 1,970 1.4 Low to Moderate 

Greasewood 1,080 0.8 Low to Moderate 

Juniper 250 0.2 Low 

Rock Outcrop 5,670 4.1 Low 

Mined Area3 4,400 3.2 Low to Moderate 

Seminoe Reservoir Lake4 9,350 6.8 --

Total 137,000 100.0 --

Notes: 

1. See Figure 44, Vegetation Map. 

2. These represent the estimated areas of the various vegetation communities within the EIS analysis area. 

3. Because coal mining companies maintain reclamation bonds on reclaimed land with the Wyoming DEQ, 

Land Quality Division, any redisturbance of bonded mine reclaimed areas by operations at the Seminoe 

Road Project would require a transfer of reclamation success liability and responsibility from the coal mining 

company to the Proponent. 

4. Acreage at normal high water level of Seminoe Reservoir, not vegetation community, but listed here to 

illustrate relative size of reservoir within EIS analysis area. 

Reference (HydroGeo 2004) 

Pedestalling and sheet wash have commonly occurred across this vegetation community, and 

transition zones are moderately broad. The broadest zone is located in the northern portion of the 

EIS analysis area where this unit borders the Low Shrub/Mixed Grass Community. 

3.6.1.2 Wyoming Sagebrush/Threadleaf Sedge

This vegetation community shares many characteristics of the Wyoming Sagebrush/Mixed Grass 

Community but differs in its overall vegetation composition. The community occurs over broad 

expanses on all aspects and is most prevalent in the eastern half of the EIS analysis area. The 

upland topography is nearly level to moderately rolling. 

Wyoming Sagebrush dominates this community, with threadleaf sedge the most common 

understory species. Sandberg bluegrass, green needlegrass, Indian ricegrass, and thickspike 

wheatgrass are also found in the understory of this community. In sandy soils, green needlegrass 

3­42 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

or needle-and-thread dominates the understory. Vegetation cover typically ranges from 30 to 40%, 

although cover values up to 50% may be found. 

Pedestalling and sheet wash are common across this vegetation community, and vegetation 

transition zones are also moderately broad, but not to the extent displayed by the Wyoming 

Sagebrush/Mixed Grass Community. 

3.6.1.3 Wyoming Sagebrush/Green Rabbitbrush

This vegetation community occurs on rolling hills and ridges in the southeastern part of the EIS 

analysis area. Wyoming sagebrush and Green rabbitbrush (Chrysothamnus viscidiflorus) 

dominate this community. Rubber rabbitbrush (Chrysothamnus nauseosus) may be an occasional 

co-dominant species. Threadleaf sedge is the most common understory species with Sandberg 

bluegrass also present. Vegetation cover typically ranges from 25 to 35%. Pedestalling was 

common. 

Broad transition zones exist between this community and the adjacent Wyoming Sagebrush/ 

Mixed Grass and Wyoming Sagebrush/Threadleaf Sedge communities. 

3.6.1.4 Low Shrub/Mixed Grass

This vegetation community is common across the central portion of the EIS analysis area and 

occupies a wide variety of sites including upland ridge tops and dissected side-slopes, broad 

alluvial plains, saline basins, and alkali flats. This community also comprises the largest 

vegetation delineation in the EIS analysis area, and occurs on flat to steeply sloping areas 

although it is most prevalent on gentle slopes. The soils supporting this community are typically 

alkaline and may or may not be saline. 

This community is typically dominated by a Gardner’s saltbush (Atriplex gardneri)/Sandberg 

bluegrass association. A Gardner saltbush/birdsfoot sagebrush (Artemisia pedatifida) type is also 

common on more level areas and, with a notable percentage of foxtail barley (Critesion jubatum), 

can be found in association with playa areas. In certain locales, birdsfoot sagebrush can be locally 

dominant on hillsides and ridge tops. Plant cover values for this community generally range from 

20 to 30%, but values can approach 40%. 

Seminoe Road Gas Development Project 3­43
Draft Environmental Impact Statement November 2005

Pedestalling was common and some sheet wash is found in this unit. Transition zones can be 

exceptionally broad, particularly when bordering the Wyoming Sagebrush/Mixed Grass and 

Wyoming Sagebrush/Threadleaf Sedge communities. 

3.6.1.5 Mixed Sagebrush

This vegetation community is limited to the southern half of the EIS analysis area on moderately 

steep to steep ridges and hills. Wyoming sagebrush, birdsfoot sagebrush, fringed sagebrush 

(Artemisia frigida), and black sagebrush (Artemisia nova) are interspersed throughout this 

community, depending on site-specific conditions. A few isolated stands of Rocky Mountain 

juniper (Juniperus scopulorum) to small to delicate trees are also found in this unit. Understory 

grass species include threadleaf sedge, Sandberg bluegrass, and western wheatgrass. Percent 

total plant cover is highly variable across this unit ranging, on average, from 25 to 70%. 

Vegetation transition zones are narrow to moderately broad, depending on slope and soil 

characteristics. Pedestalling, sheet wash and riling are common, and some gullying was 

observed. 

3.6.1.6 Mixed Shrub

This vegetation community occurs primarily on ridge complexes and hills where slopes are 

moderate to steep. At higher elevations, mountain mahogany (Cercocarpus montanus), 

skunkbush sumac (Rhus aromatica var. trilobata), squaw current (Ribes cereum), and black 

sagebrush are present. Further downslope, Wyoming sagebrush becomes a sub-dominant 

community component with shrub species such as broom snakeweed (Gutierrezia sarothrae) and 

shadscale saltbush (Atriplex confertifolia) occurring in association. On south-facing slopes, 

shadscale saltbush dominates where soil moisture regimes are drier. A Wyoming 

sagebrush/greasewood (Sarcobatus vermiculatus) association occurs in drainages along toe 

slopes. 

Plant cover is highly variable within this community ranging from 10% (across surface rock 

exposures) to 70% (on north- and east-facing aspects with deeper soils). Herbaceous understory 

species include Sandberg bluegrass, green needlegrass, Indian ricegrass, and western 

wheatgrass. 

3­44 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Transition zone and erosion characteristics of this unit are similar to those of the Mixed 

Sagebrush Community. 

3.6.1.7 Mixed Grass

Threadleaf sedge, Sandberg bluegrass, Indian ricegrass, and thickspike wheatgrass dominate 

this vegetation community, which is found on nearly level to gently rolling areas. Green 

needlegrass dominates where more sandy soils occur. Plant cover ranges from about 25 to 35%. 

Wyoming sagebrush has established in incised drainages within this unit where soils are 

sufficiently deep, while mountain mahogany occurs as an occasional community inclusion. 

Vegetation community transition zones range from abrupt in the Mixed Sage Community (due to 

slope) to comparatively broad where it borders the Wyoming Sagebrush/Mixed Grass Community. 

Pedestalling and sheet wash are common in this community. 

3.6.1.8 Threadleaf Sedge/Mixed Grass

This vegetation community is similar to the Mixed Grass Community with the exception that 

threadleaf sedge is the dominant herbaceous species. This unit occurs over nearly level to gently 

rolling uplands and is typified by vegetation cover values ranging from 20 to 30%. Community 

component species include Sandberg bluegrass, needle-and-thread, Indian ricegrass, and 

western wheatgrass. Broom snakeweed and low density Wyoming sagebrush stands are also 

present. The Alkali Flat playa is included in this unit. 

Pedestalling was noted in this community. Transition zone characteristics parallel the Mixed 

Grass Community. 

3.6.1.9 Basin Big Sagebrush/Greasewood

This vegetation community has become established along drainages and depressions, and in 

swales where greasewood does not dominate. It can also be found in association with alkali flat 

and playa communities upslope from areas dominated by more calcareous and salt tolerant 

species. Mixed shrub species are often intermixed with the Basin Big Sagebrush (Artemisia 

tridentata var. tridentata)/Greasewood (Sarcobatus vermiculatus) Community where better quality 

soils border drainages. This community is more common than the Greasewood Community on 

broad stream terraces because of the adaptive capabilities of Basin Big Sagebrush. 

Seminoe Road Gas Development Project 3­45
Draft Environmental Impact Statement November 2005

Plant cover ranges between 50 and 80%. This community often transitions into a Greasewood 

Community in drainage topographies. Pedestalling and sheet wash are common. 

3.6.1.10 Greasewood

Similar to the Basin Big Sagebrush/Greasewood Community described in Section 3.6.1.9, Basin 

Big Sagebrush/Greasewood, this community is found in depressions, basins, stream courses and 

stream terraces where wetter soil moisture regimes have developed. It is also commonly 

associated with alkali flats and playas. Slopes are typically gentle, with deep soils that exhibit a 

basic (high) pH. Higher than normal soil salinities may occur. Pedestalling and sheet wash are 

common in this community. 

Plant cover typically ranges from 50 to 80% with alkali sacaton (Sporobolus airoides) a common 

understory component. Vegetation community transition zones range from abrupt to broad, 

particularly where this community intergrades with the Basin Big Sagebrush/Greasewood 

Community. 

3.6.1.11 Juniper

This vegetation community is rare but does occur sporadically on foothills, ridge tops and steep 

ridges in the southwest part of the EIS analysis area. This community may also be found 

intermixed at higher elevations within the Mixed Shrub and Mixed Sagebrush communities where 

steep to very steep slopes are overlain by shallow soils having a high coarse fragment content. 

Surface rock exposures and rock outcrops are relatively common. 

Rocky Mountain juniper is the dominant species in this community. Plant cover ranges from 30 to 

50% (including the tree canopy) though significant bare areas can be found. The plant understory 

ranges from a mixed shrub type on slopes to black sagebrush stands on more exposed ridge 

tops. A gravel pavement is common indicating a susceptibility to erosion. Vegetation community 

transition zones are abrupt to narrow along toe-slopes where an increase in soil depths promote 

the establishment of shrub and grass-dominated communities. 

3.6.1.12 Playas

Ferris Lake, Alkali Flat and St. Mary’s Anticline Basin are playas occurring within the EIS analysis 

area. Each consists of a closed basin into which drainage flows from the surrounding terrain. 

Playas pond water during springtime snowmelt or after an intense summer thunderstorm, but are 

3­46  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

relatively dry for most of the year. Depending upon annual precipitation rates, playas are either 

unvegetated or support limited stands of herbaceous species. Foxtail barley and annual species 

such as prostrate knotweed (Polygonum aviculare), and silverscale saltbush (Atriplex argentea) 

are commonly supported by playas where growing conditions are amenable. 

3.6.1.13 Rock Outcrop/Broken Land/Miscellaneous Land Types

Rock outcrops, surface rock exposures and highly weathered geologic formations are scattered 

throughout the EIS analysis area. These sites are typified by little or no soil, high surficial coarse 

fragments and sparse vegetation. Sand beaches along the shoreline of Seminoe Reservoir are 

also included in this unit. Where soils have accumulated along toe slopes, in depressions, or in 

broader incised drainages, a variation of the Mixed Shrub Community often develops. The 

potential for erosion is highly variable, given the lack of soil across major portions of this unit, 

though considered “high” where soil exists and a gravel pavement is absent. 

3.6.1.14 Mined Area

Surface coal mining has occurred within the EIS analysis area. See Appendix E, Regional 

Activity. The areas affected by this mining activity have been delineated into a unique category 

and are in various stages of reclamation. 

3.6.2 Wetlands and Riparian Areas

No formal delineations of jurisdictional wetlands or other Waters of the U.S. have been completed 

for the EIS analysis area. To complete this section, information from 2001, 2002, 2003 and 2004 

baseline and follow up field surveys were used to describe the essential characteristics of 

drainage vegetation, wetlands and riparian areas. (TRC Mariah 2001; HydroGeo 2003a, 2004c). 

In addition, National Wetlands Inventory maps, utilizing the wetland classification described by 

Cowardin et al. (1979), were reviewed. 

Wetland and riparian plant communities occur in all 14 sub-watersheds in the EIS analysis area. 

Other than those associated with Seminoe Reservoir, the North Platte River, seeps, springs, stock 

ponds and playas, they are typically confined to areas in or adjacent to the drainage channels. 

Wetland hydrology is provided by channel flooding, lateral flow and subirrigation. The wetland 

hydrology in Pool Table Draw is also enhanced by the continuous flows of Pilot Project produced 

water. 

Seminoe Road Gas Development Project 3­47
Draft Environmental Impact Statement November 2005

Wetland and riparian zones along drainages are generally characterized by narrow vegetation 

communities that have wetter soil hydrologic conditions than the surrounding upland areas. 

Wetland and riparian vegetation communities vary across the EIS analysis area, but they are 

comparatively simplistic in terms of diversity. Species occurring within these wetland and riparian 

areas have become established in direct response to soil/hydrologic conditions reflecting soil 

depth, water holding capacity, and period of saturation. Six wetland and riparian plant 

communities are found in the EIS analysis area. 

Herbaceous Riparian. This community is confined to areas within drainages and occurs 

primarily on the banks and in channel bottoms of ephemeral drainages. Hydrophytic grasses, 

rushes (Juncus spp.), sedges (Carex spp.) and forbs are the dominant species. The plant species 

presented in the upper, drier reaches of the drainages varies from those found in lower, wetter 

reaches, including those drainage sections that have standing or gently flowing water. Aquatic and 

floating vegetation growing in standing or gently flowing water is included in this community. 

Shrubby Riparian. This community is confined to areas within and along drainages. It is 

characterized by shrubby vegetation growing in channel bottoms and on the banks of ephemeral 

drainages. The dominant shrub species varies throughout drainages and overlaps the Basin Big 

Sagebrush/Greasewood and Greasewood communities immediately upslope from the drainage 

proper as described in sections 3.6.1.9, Basin Big Sagebrush/Greasewood and 3.6.1.10, 

Greasewood. This community also includes areas in the lower reaches of most drainages where 

the water table is high and sandbar willow (Salix exigua) and tamarisk (Tamarisk chinensis) are 

the dominant shrubs. 

Wet Meadow. This community typically occurs in areas adjacent to drainage flow channels and 

springs where soils are saturated for a portion of the growing season. This community also 

includes sub-irrigated vegetated terraces and drainage areas downstream of stock ponds. 

Hydrophytic grasses, rushes, sedges, and forbs are the dominant species. 

Forested Riparian. This community is characterized by deciduous trees such as cottonwood 

(Populus spp.). Cottonwood trees are very rare in the EIS analysis area; however, they do occur in 

small isolated locations along the North Platte River. 

3­48  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Playa. The Ferris Lake and Alkali Flat and St. Mary’s Anticline playa areas occur in the EIS 

analysis area south of the North Platte River. These closed playa basins can be inundated with 

water for a few months of the year (depending on weather conditions) and support hydrophytic 

vegetation. During drought cycles, vegetation cover can disappear (HydroGeo 2003a, 2004c). 

This community is also described in Section 3.6.1.12, Playas. 

Shoreline/Sandy Beach. The fluctuating water levels of the Seminoe Reservoir create 

shoreline and sandy beach conditions. During drought conditions (such as experienced over the 

past several years), vast areas of shoreline are exposed, and little or no vegetation grows in these 

areas with the exception of scattered weedy and annual species, and alkali-tolerant hydrophytic 

grasses, rushes and forbs. Although highly variable in size depending on weather conditions and 

reservoir storage levels, wetland plant communities have developed in the lower reaches of many 

EIS analysis area drainages, above the normal high water level of the Seminoe Reservoir. These 

areas are subjected to varying water levels and erosion. The shoreline/sandy beach community 

overlaps the community described in Section 3.6.1.13, Rock Outcrop/Broken Land/Miscellaneous 

Land Types. 

3.6.2.1 Pilot Project Produced Water Riparian and Wetland Areas

Since December 2001, Pilot Project produced water has been released into Pool Table Draw. 

Prior to the introduction of produced water, Pool Table Draw was a sparsely vegetated ephemeral 

stream channel (TRC Mariah 2001). The presence of continuous, low velocity flows of Pilot 

Project produced water have enhanced the development of hydric soils and increased the 

vegetative cover and diversity of riparian and wetland species along narrow bands of Pool Table 

Draw and some localized areas in Pool Table Draw where the gradient flattens along the channel 

(HydroGeo 2003a, 2004c). Sagebrush and greasewood are less tolerant of anaerobic conditions 

and are stressed or dying in isolated areas where soils are becoming saturated due to the 

continuous flows of Pilot Project produced water. 

3.6.2.2 Seeps, Springs and Stock Ponds

Seeps and springs are naturally occurring and exhibit seasonal or perennial flows with recharge 

coming from direct precipitation or snowmelt infiltration. Known springs in the EIS analysis area 

are shown on Figure 33, Hydrologic Monitoring Sites Location Map. It is estimated that 10 to 

15 stock ponds are located within the EIS analysis area. Depending on soil moisture conditions, 

Seminoe Road Gas Development Project 3­49
Draft Environmental Impact Statement November 2005

the areas surrounding seeps, springs, and stock ponds support hydrophytic wetland vegetation, 

occurring in herbaceous and shrubby riparian to wet meadow communities. 

Stock ponds are man-made features that are filled by flow from springs or overland flow. 

Hydrophytic vegetation often grows in areas surrounding stock ponds due to seepage. The areal 

extent is typically limited and such vegetation can be damaged by animal use or the stock ponds. 

3.6.3 Weeds

The existence, extent and type of weeds likely to inhabit an area is affected by many factors 

including elevation, slope aspect, soil pH, soil texture, distance from water sources, distance from 

disturbance, proximity to existing infestations, annual precipitation, and vegetation cover. 

Additionally, with the windy conditions of south-central Wyoming, weed seeds can be blown from 

great distances to gain “foot holds” in disturbed or stressed sites. 

The EIS analysis area is comparatively undisturbed and dominated by native vegetation species 

with relatively low weed and cover. Weeds are prone to establishment on disturbed sites such as 

those resulting from human (recreation, ranching, and livestock) activities. The drought conditions 

of the past several years have also contributed to the spread of weeds. 

Pilot Project related activities such as the construction of roads, drill pads, pipelines, reservoir 

improvements, and ancillary facilities have resulted in surface disturbances of 146 acres that have 

enhanced the establishment and spread of weeds. The presence of continuous flows of produced 

water in Pool Table Draw has also resulted in increased growth and diversity of plant species 

including weeds (HydroGeo 2003a, 2004c). In general, weeds develop in disturbed sites 

throughout the EIS analysis area with varying density and composition (TRC Mariah 2001, 

HydroGeo 2003a, 2004c). Weeds are typically confined to narrow corridors along roadways, areas 

disturbed by ranching, recreational use; areas disturbed by the Pilot Project and County Road 351 

construction activities; areas impacted by livestock such as surrounding stock ponds; areas 

subject to erosion including headcuts; and areas exposed by fluctuating water storage levels in 

Seminoe Reservoir. 

The state of Wyoming, Carbon County, and BLM weedy species of concern known to occur in the 

EIS analysis area are presented on Table 3.6.2, State of Wyoming Designated Noxious 

3­50  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Weeds, BLM Weedy Species of Concern, and Carbon County Declared Weeds Known to 

Occur in the EIS Analysis Area. 

The information on weed species occurrences was based on information provided by the BLM Field 

Office (Foley 2003) and data collected in surveys conducted in 2001-2004 (TRC Mariah 2001; 

HydroGeo 2003a, 2004c). Nine designated noxious weeds, four BLM weedy species of concern, and 

three Carbon County declared weeds are known to occur in or near the EIS analysis area. BLM and 

State of Wyoming regulations require that noxious weeds be controlled where they become newly 

established. 

3.6.4 Threatened and Endangered Plant Species

There are no known threatened, endangered, candidate, or proposed plant species or critical 

habitats in the EIS analysis area (TRC Mariah 2001, HydroGeo 2003, 2003a, WYNDD 2003, 

2004). However, the blowout penstemon (Penstemon haydenii), an endangered plant species, is 

known to occur in the Ferris and Seminoe mountains north of the EIS analysis area (WYNDD 

2004). There are no known active sand dunes or areas of potential habitat for blowout penstemon 

in the EIS analysis area. Based on known distribution and habitat characteristics for blowout 

penstemon, this species is not likely to occur in the EIS analysis area. 

3.6.5 Sensitive Plant Species

Persistent sepal yellow-cress, the only BLM sensitive plant species of concern known to be 

present in the EIS analysis area, occurs in portions of Pool Table Draw, Ayers Draw, Dry Ditch, St. 

Mary’s Ditch, Mountain Lion Draw and the Ferris Lake playa (TRC Mariah 2001). It occurs on 

banks adjacent to standing or flowing water, along the shoreline of Seminoe Reservoir near the 

high water line, and in areas subject to flooding. It frequently occurs in semi-disturbed and recently 

flooded areas, so it occurs with varying density from year to year and may not be observed when 

water levels are high. There are seven known occurrences of persistent sepal yellow-cress, 

mostly on the shores of Seminoe Reservoir, that represent nearly 33% of all occurrences in 

Wyoming and there are no extant occurrences of this species outside of Wyoming (WYNDD 

2004). The WYNDD (2002) notes occurrences of persistent sepal yellow-cress as comprising 

“one of the highest concentrations of this species in the state.” 

Seminoe Road Gas Development Project 3­51
Draft Environmental Impact Statement November 2005

Table 3.6-2, State of Wyoming Designated Noxious Weeds, BLM Weedy Species of 

Concern, and Carbon County Declared Weeds Known to Occur in the EIS Analysis Area 

Common Name Scientific Name Comments3,4 Observed in Field 

Surveys4 

State of Wyoming Designated Noxious Weeds1 

Canada thistle Cirsium arvense Yes 

Dalmation toadflax Linaria dalmatica 

Known t occur north of the project 

area along road right-of-way and 

outside right-of-way in native 

rangeland 

No 

Diffuse knapweed Centaurea diffusa 

Known to occur north of the project 

area along road right-of-way and 

outside right-of-way in native 

rangeland. Some areas are being 

treated already.

3 

No 

Leafy spurge Euphoribia esula 

Known to occur along the North 

Platte River where pipeline route is 

proposed to bore under.

3 

No 

Russian knapweed Centaurea repens 

Known to occur north of the project 

area along road right-of-way and 

outside right-of-way in native 

rangeland.

3 

Yes 

Salt cedar, tamarisk Tamarisk spp. Known to occur along Seminoe 

Reservoir.

3 Yes 

Scotch thistle Onopordum acanthium 

Known to occur near CBM well on 

west side of road in drainage 

bottom. Small patch being treated.

3 

Not observed in 2002 or 2003 

surveys but three individuals 

observed in summer 2004.

3 

Yes 

Spotted knapweed Centaurea maculosa 

Known to occur north of the project 

area along road right-of-way and 

outside right-of-way in native 

rangeland. Some areas are being 

treated already.

3 

No 

Whitetop, Hoary cress Cardaria spp. Known to occur along highway.

3 Yes 

BLM Weed Species of Concern2 

Cheatgrass Bromus (Anisantha) 

tectorum Yes 

Curlycup gumweed Grindelia squarrosa Yes 

Halogeton Halogeton glomeratus Yes 

Russian thistle Salsola tragus Yes 

Annual chenopods Specific plant species not identified 

by BLM Yes 

Annual mustards Specific plant species not identified 

by BLM Yes 

2003 List of Declared Weeds for Carbon County5 

Halogeton Halogeton glomeratus Yes 

Plains larkspur Delphinium geyeri Yes 

Plains pricklypear Opuntia polyacantha Yes 

Wyeth lupine Lupinus wyethi No 

Notes: 

1. Adapted from Designated Noxious Weed List – Wyoming Weed and Pest Control Act (Wyoming Weed and 

Pest Council). 

2. BLM Weed Species of Concern (Foley 2003) 

3. Adapted from Foley (2003, 2004). 

4. Adapted from HydroGeo (2003a, 2004); TRC Mariah (2001). 

5. Adapted from 2003 Declared List of Weed and Pests for Carbon County (Wyoming Weed and Pest Council). 

3­52 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.7 Wildlife/Fisheries

Information regarding wildlife species and current habitat conditions within and near the EIS 

analysis area was obtained from field surveys and reports completed for the Seminoe Road Pilot 

Project Area and Gas Gathering Pipeline and Access Roads Project (USDI, BLM 2001; TRC 

2000, 2002a, 2002b, 2002c, 2002d, 2002e; and Cedar Creek Associates, Inc. 2004), published 

sources pertinent to the area, BLM file information, and WGFD information, discussions with the 

USFWS, and Wyoming Natural Heritage Program (WNHP) file and mapping data. 

3.7.1 Big Game

Pronghorn, mule deer, elk and bighorn sheep are the four big game species that occupy habitats 

on or near the EIS analysis area. Populations of mule deer, elk and bighorn sheep are mostly 

peripheral to the EIS analysis area, while pronghorn is the only common big game resident. The 

following information presented on population trends for big game animals is taken from the 

WGFD’s 2002 Annual Big Game Unit JCRs. 

3.7.1.1 Mule Deer

Mule deer populations in the region are part of the Ferris Herd Unit (647, Hunt Area 87) west of 

Seminoe Reservoir and north of the North Platte River and part of the Platte Valley Herd Unit 

(541, Hunt Area 161) east of Seminoe Reservoir and south of the North Platte River. The EIS 

analysis area north of the North Platte River is outside of occupied mule deer range, but the area 

south of the river is yearlong mule deer range. Crucial winter/yearlong mule deer range is located 

to the south along the North Platte River and west and north of the EIS analysis area (see Figure 

45, Wildlife Map). Crucial winter/yearlong range is defined by the WGFD as winter/yearlong 

range that has been documented as the determining factor in a population’s ability to maintain 

itself at a desired level over the long-term. 

Since 1990, the Ferris Mule Deer Unit has not met the WGFD population objective of 5,000 

animals. Poor fawn production in 1991 and 1992, coupled with heavy losses in the 1992-93 

winter, reduced the herd to less than one half the objective size. Reductions in fawn production 

continued until 1998 when fawning returned to more normal levels; however, there were increased 

losses of fawns during the 2000-01 winter. Current estimates place the overall population at less 

than half the objective population in spite of conservative harvests over the past decade. 

Seminoe Road Gas Development Project 3­53
Draft Environmental Impact Statement November 2005

The Platte Valley Herd Unit includes the west slope of the Snowy Range and the east slope of the 

Sierra Madre Range, including the North Platte River valley. The eastern edge of the EIS analysis 

area (Hunt Area 161) supports drier and less productive habitats for mule deer, but it is included in 

the Platte Valley Herd Unit because during more severe winters mule deer migrate from higher 

elevation habitats to winter range in Hunt Areas 161 and 83. Summer and fall densities of mule 

deer in Hunt Areas 161 and 83 are low. The mule deer population objective for the Platte Valley 

Herd Unit is 20,000 animals. Following the 2002 hunting seasons, the population was estimated at 

25,900 deer, almost 30% above the WGFD objective. 

3.7.1.2 Elk

The entire EIS analysis area is outside of occupied elk range, but elk may occasionally pass 

through the project area. Elk populations west of the Seminoe Reservoir and north of the North 

Platte River are part of the Ferris Herd Unit (639, Hunt Area 111). Elk populations east of 

Seminoe Reservoir and south of the North Platte River are part of the Shirley Mountain Herd Unit 

(534, Hunt Area 16). 

3.7.1.3 Bighorn Sheep

Bighorn sheep reside north of the EIS analysis area in the Ferris/Seminoe Mountains. The area is 

closed to hunting. 

3.7.1.4 Pronghorn

Pronghorn populations within and surrounding the EIS analysis area are separated into two herd 

units: 

� South Ferris Herd Unit (637, Hunt Area 62) - located west of Seminoe Reservoir and 

north of the North Platte River; and, 

� Medicine Bow Herd Unit (525, Hunt Area 48) - located east of Seminoe Reservoir and 

south of the North Platte River. 

The majority of the EIS analysis area is classified as winter/yearlong range. See Figure 45, 

Wildlife Map. Winter/yearlong winter range is defined by the WGFD as range that is used 

yearlong; but, during winter, the area has a substantial influx of pronghorn from other seasonal 

ranges. 

3­54 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

The WGFD population objective of 6,500 animals for the South Ferris Pronghorn Herd Unit has 

not been met since the 1992-93 winter, and subsequent years of poor fawn production have 

hindered recovery from that winter. Fawn production improved in the late 1990s but decreased 

from 2000 to 2002. The estimated post-hunt population in 2002 was roughly 20% less than the 

objective population. 

The pronghorn population in the Medicine Bow Herd Unit likewise declined after the 1992-93 

winter. The WGFD population objective of 60,000 animals has not been met since 1991, despite 

mild winters over the last several years and conservative hunting license numbers. Poor habitat 

conditions appear to be limiting population growth in this herd unit, and hunting license numbers 

were increased in 2002 and 2003 to reduce pronghorn foraging pressure on habitat. 

3.7.2 Predators, Furbearers, and Small Mammals

Due to the secretive nature and nocturnal habits of many furbearers and other small mammals, 

the specific distribution and population densities within the EIS analysis and surrounding areas are 

unknown. Furbearers and predators known or likely to occur in the area include coyote, badger, 

red fox, swift fox, ermine, long-tailed weasel, western spotted skunk, striped skunk, bobcat, and 

beaver. All of these species, except for beaver, are adapted to a wide range of grassland and 

shrubland habitats. Distribution of beaver is restricted to aquatic habitat along the North Platte 

River. Further discussion of swift fox is provided in Section 3.7.8.3, Swift Fox. 

Other small mammals known or likely to be common inhabitants of the region include desert 

cottontail, white-tailed jackrabbit, white-tailed prairie dog, thirteen-lined ground squirrel, least 

chipmunk, Wyoming ground squirrel, deer mouse, olive-backed pocket mouse, Ord’s kangaroo 

rat, and sagebrush vole. Further discussion of white-tailed prairie dog is provided in Section 

3.7.8.1, White-tailed Prairie Dog. 

3.7.3 Waterbirds

Waterbirds include waterfowl, shorebirds and other wading birds typically associated with 

wetlands and bodies of surface water. Within the EIS analysis area, aquatic and wetland habitat 

for waterbirds is restricted to the North Platte River, Seminoe Reservoir, and a few scattered stock 

ponds. Various species of waterfowl, shorebirds and waders utilize these water bodies during 

spring and fall migration, but few remain as summer residents and breeders. Fluctuations in 

Seminoe Reservoir water levels prohibits the development of shallow water shoreline areas with 

Seminoe Road Gas Development Project 3­55
Draft Environmental Impact Statement November 2005

emergent vegetation, favored by many species of waterfowl and shorebirds. Therefore, waterbird 

nesting use of the reservoir is limited. Waterbird nesting in the area is limited primarily to species 

such as puddle ducks (mallard, teal, etc.), spotted sandpiper, and killdeer. White pelicans and 

double-crested cormorants are known to forage for fish in Seminoe Reservoir (WGFD 1998). 

3.7.4 Raptors

Raptor species known or likely to hunt in the open shrublands and grasslands and possibly nest 

within the EIS analysis area are turkey vulture, northern harrier, bald eagle, golden eagle, 

peregrine falcon, prairie falcon, red-tailed hawk, ferruginous hawk, American kestrel, burrowing 

owl, short-eared owl, and great horned owl. BLM file information and recent field surveys (TRC 

2000 and Cedar Creek Associates 2004) have documented nesting by golden eagle, ferruginous 

hawk, red-tailed hawk, American kestrel, great horned owl, and burrowing owl. Additional 

discussion of bald eagle, peregrine falcon, and ferruginous hawk is provided in Section 3.7.8, 

Threatened, Endangered and Other Species of Concern. 

Suitable nest sites for red-tailed hawk, golden eagle, and great horned owl are provided by large 

cottonwood trees, cliff ledges, and rock outcrops along the North Platte River and Seminoe 

Reservoir, as well as by isolated rock outcrop and escarpments scattered throughout the upland 

areas. Great horned owls do not build their own nests and often occupy old nests of eagles, 

hawks, ravens, and crows, in larger trees or on cliff faces. Turkey vultures nest on cliff ledges, in 

hollows in snags or stumps, or in caves, while prairie falcons nest on cliff ledges or in rock 

cavities. 

Northern harriers usually nest on the ground or in low shrubs in pockets of dense shrub and grass 

cover, along drainages or near wetlands. The American kestrel is a cavity nester using 

abandoned woodpecker holes, magpie nests and rock outcrop crevices. Short-eared owls prefer 

habitats of shortgrass prairie, agricultural areas, and marshes (Andrews and Righter 1992; Ehrlich 

et al. 1988), 

3.7.5 Upland Game Birds

Greater sage-grouse are the only upland game bird inhabitants in the EIS analysis area. A 

discussion of greater sage-grouse is provided in Section 3.7.8.10, Greater Sage-grouse. 

3­56  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

3.7.6 Migratory Birds

The Migratory Bird Treaty Act (MBTA) provides federal legal protection of migratory bird species, 

and the BLM is required to evaluate the potential effects of a project on such species. A draft 

USFWS Memorandum of Understanding (MOU) defines BLM responsibilities under the MBTA. 

The MOU directs the BLM to avoid or minimize the unintentional take of migratory birds to the 

extent practicable. The MOU also places high management priority on Birds of Conservation 

Concern (BCC) identified by the USFWS (USFWS 2002). 

The BCC listings for the Badlands and Prairies, Shortgrass Prairie, and USFWS Region 6 

(USFWS 2002) were reviewed and the birds on these listings that are known or potential breeders 

within the EIS analysis area include golden eagle, ferruginous hawk, northern harrier, peregrine 

falcon, prairie falcon, burrowing owl, short-eared owl, mountain plover, long-billed curlew, Wilson’s 

phalarope, loggerhead shrike, and Brewer’s sparrow. A number of other species, including the 

American golden plover, marbled godwit, buff-breasted sandpiper, sanderling, Sprague’s pipit, 

and Le Conte’s sparrow, may occur as occasional or accidental migrants in the EIS analysis area 

during spring and fall migration. 

Potential nesting habitat for raptors is discussed in Sections 3.7.4, Raptors. Bird species listed as 

threatened, endangered or BLM sensitive are discussed in Section 3.7.8, Threatened, 

Endangered and Other Species of Concern. 

Long-billed curlew, mountain plover and Brewer’s sparrow are Neotropical migrants which may 

occur in the area from spring through early fall. Loggerhead shrike and Brewer’s sparrow winter in 

the southwestern United States and Mexico. The mountain plover winters in California and 

Mexico. Additional discussion on these three bird species is found in Section 3.7.8, Threatened, 

Endangered and Other Species of Concern. 

The breeding range of Wilson’s phalarope includes the EIS analysis area; this Neotropical migrant 

is a semi-colonial nester that prefers to nest at the margins of quiet, shallow waters of ponds and 

sloughs, ashore or on islets (Terres 1980). Nests for Wilson’s phalarope are well concealed in 

moist meadows or other wetland habitats often surrounded by water (Ehrlich et al. 1988). Suitable 

nesting habitat for this species within the EIS analysis area is limited to backwater areas along the 

North Platte River or stock ponds with a semi-permanent water source and well-developed 

peripheral wetlands. 

Seminoe Road Gas Development Project 3­57
Draft Environmental Impact Statement November 2005

3.7.7 Fisheries

Aquatic habitats supporting fisheries in the area are limited to Seminoe Reservoir and the North 

Platte River. The “Miracle Mile” reach of the North Platte River, considered to be a “world-class” 

tailwater fishery, is located north of the EIS analysis area between Kortes Dam and Pathfinder 

Reservoir. Data on the North Platte River between Seminoe Reservoir and Interstate 80 (I-80) 

was obtained from Regional River Data provided by Mike Snigg, WGFD 2004. 

The Seminoe Reservoir exhibits large annual water level fluctuations, averaging 37 vertical feet 

between 1968 and 1998 (WGFD 1998). Drought conditions over the last several years have 

resulted in an even greater seasonal decline in minimum water levels. The reservoir fills during 

spring and early summer, then water levels decrease during the mid and late summer irrigation 

season. Water levels further drop as water is released for downstream storage in Glendo 

Reservoir. These annual water level fluctuations in the Seminoe Reservoir tend to limit fisheries 

productivity. 

The principal game fish in Seminoe Reservoir are walleye, rainbow trout, and brown trout, 

although some remnants of the historically-planted Snake River cutthroat trout are also present. 

Other common non-game fish species (carp, lake chub, emerald shiner, white sucker, longnose 

sucker and fathead minnow) are also present in the reservoir. Fishermen first reported walleye in 

Seminoe Reservoir in 1961. Walleye apparently drifted into the reservoir from upstream stocking 

in Colorado, and this species is now abundant in the reservoir. Brown trout exist as a wild selfsustaining population after historic stocking efforts in the North Platte River above the Seminoe 

Reservoir. The WGFD’s current fishery management emphasis for the Seminoe Reservoir is on 

annual autumn stocking of approximately 120,000 9-inch rainbow trout and on maintaining a wild 

walleye fishery (Condor 2004). 

Boats provide most of (and probably the best) access for fishing in the Seminoe Reservoir; there 

are one private and three public boat ramps. Road access for bank fishing is poor, given 

surrounding private property. Further, for most of the year, expanses of exposed shoreline 

“mudflats” also restrict bank fishing opportunities. The WGFD’s angler use management objective 

for the Seminoe Reservoir is to support 40,000 angler days per year (Condor 2004). Actual angler 

use was estimated at 33,250 angler days per year in 1998 (WGFD 1998). 

3­58  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

The North Platte River between Seminoe Reservoir and I-80 is managed by the WGFD as a wild 

trout fishery, and its Wyoming Trout Stream Class is “yellow.” Game fish management 

emphasizes brown trout, rainbow trout, cutthroat trout, and walleye. Brown trout are the most 

abundant game fish in this stretch of the North Platte River, with rainbow trout, walleye, and 

Snake River cutthroat also present in descending order of abundance. Other native and nonnative non-game fish species present in the river are bigmouth shiner, creek chub, carp, emerald 

shiner, Iowa darter, longnose dace, longnose sucker, and white sucker (Snigg 2004). 

3.7.8 Threatened, Endangered and Other Species of Concern

The USFWS provided a listing of threatened, endangered and candidate species for south-central 

Wyoming, and the BLM provided a listing of their sensitive species for the Rawlins Field Office 

area. See Table 3.7-1, Threatened, Endangered and BLM Sensitive Species Potentially 

Occurring Within the EIS Analysis Area. Based on the initial evaluation and screening of the 

listed species, one federal endangered, one federal threatened species, and thirteen BLM listed 

sensitive species may occur within the EIS analysis area. In addition, four federal endangered and 

two threatened species have been identified as susceptible to downstream water depletions in the 

North Platte River system. Discussions of these species follow. 

Table 3.7-1, Threatened, Endangered and BLM Sensitive Species Potentially Occurring 

Within the EIS Analysis Area 

Species 

Common Name 

Scientific Name 

USFWS Status/ or 

BLM Sensitive 

Exclusion 

from Analysis 

Reason for 

Exclusion from 

or Inclusion in 

Analysis 

Mammals 

Long-eared myotis Myotis evotis Sensitive Yes 

No suitable 

habitat in EIS 

analysis area 

Fringed myotis Myotis thysanodes Sensitive Yes 

No suitable 

habitat in EIS 

analysis area 

Townsend’s bigeared bat Corynorhinus townsendii Sensitive Yes 

No suitable 

habitat in EIS 

analysis area 

White-tailed prairie 

dog 

Cynomys leucurus Sensitive No 

Species 

documented in 

EIS analysis 

area 

Black-tailed prairie 

dog 

Cynomys ludovicianus Candidate Yes 

EIS analysis 

area is outside of 

known range of 

this species 

Seminoe Road Gas Development Project 3­59
Draft Environmental Impact Statement November 2005

Species 

Common Name 

Scientific Name 

USFWS Status/ or 

BLM Sensitive 

Exclusion 

from Analysis 

Reason for 

Exclusion from 

or Inclusion in 

Analysis 

Wyoming pocket 

gopher Thomomys clusius Sensitive Yes 

EIS analysis 

area is outside of 

known range of 

this species 

Black-footed ferret Mustela nigripes Endangered No 

Potential habitat 

exists for this 

species in EIS 

analysis area 

Swift fox Vulpes velox Sensitive No 

Potential habitat 

exists for this 

species in EIS 

analysis area 

Birds 

White-faced ibis Plegadis chihi Sensitive No 

Suitable nesting 

habitat lacking in 

EIS analysis 

area. May be 

present as 

occasional 

migrant 

Trumpeter swan Cygnus buccinator Sensitive No 

Suitable nesting 

habitat lacking in 

EIS analysis 

area. May be 

present as 

occasional 

migrant 

Whooping crane Grus americana Endangered No 

Vulnerable to 

water depletions 

in Platte River 

system 

Least tern Sterna antilla7rum Endangered No 

Vulnerable to 

water depletions 

in Platte River 

system 

Eskimo curlew Numenius borealis Endangered No 

Vulnerable to 

water depletions 

in Platte River 

system 

Piping plover Charadrius melodus Threatened No 

Vulnerable to 

water depletions 

in Platte River 

system 

Mountain plover Charadrius montanus Sensitive No 

Species 

documented in 

EIS analysis 

area 

Bald eagle Haliaeetus leucocephalus Threatened No 

Vulnerable to 

water depletions 

in Platte River 

system; 

observed in EIS 

analysis area 

Northern goshawk Accipiter gentiles Sensitive Yes 

No suitable 

habitat in EIS 

analysis area 

3­60  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Species 

Common Name 

Scientific Name 

USFWS Status/ or 

BLM Sensitive 

Exclusion 

from Analysis 

Reason for 

Exclusion from 

or Inclusion in 

Analysis 

Ferruginous hawk Buteo regalis Sensitive No 

Species 

documented in 

EIS analysis 

area 

Peregrine falcon Falco peregrinus Sensitive No 

Potential 

foraging and 

nesting habitat 

along N. Platte 

River 

Greater sage-grouse Centrocercus urophasianus Sensitive No 

Species 

documented in 

EIS analysis 

area 

Columbian sharptailed grouse 

Tympanuchus phasianellus 

columbianus 

Petitioned for 

listing/Sensitive Yes 

No suitable 

habitat in EIS 

analysis area 

Long-billed curlew Numenius americanus Sensitive No 

Yellow-billed cuckoo Coccyzus americanus Candidate/Sensitive Yes 

No suitable 

habitat in EIS 

analysis area 

Burrowing owl Athene cunicularia Sensitive No 

Species 

documented in 

EIS analysis 

area 

Sage thrasher Oreoscoptes montanus Sensitive No 

Species 

documented in 

EIS analysis 

area 

Loggerhead shrike Lanius ludovicianus Sensitive No 

Species 

documented in 

EIS analysis 

area 

Brewer’s sparrow Spizella breweri Sensitive No 

Species 

documented in 

EIS analysis 

area 

Sage sparrow Amphispiza belli Sensitive No 

Potential habitat 

exists for this 

species in EIS 

analysis area 

Baird’s sparrow Ammodramus bairdii Sensitive Yes 

Possible migrant 

only in EIS 

analysis area 

Fish 

Pallid sturgeon Scaphirhynchus albus Endangered No 

Vulnerable to 

water depletions 

in Platte River 

system 

Roundtail chub Gila robusta Sensitive Yes 

Activities in EIS 

analysis area 

would have no 

effect on 

Colorado River 

system 

Seminoe Road Gas Development Project 3­61
Draft Environmental Impact Statement November 2005

Species 

Common Name 

Scientific Name 

USFWS Status/ or 

BLM Sensitive 

Exclusion 

from Analysis 

Reason for 

Exclusion from 

or Inclusion in 

Analysis 

Bluehead sucker Catostomus discobolus Sensitive Yes 

Activities in EIS 

analysis area 

would have no 

effect on 

downstream 

rivers systems 

supporting this 

species 

Flannelmouth sucker Catostomus latipinnis Sensitive Yes 

Activities in EIS 

analysis area 

would have no 

effect on 

Colorado River 

system 

Colorado River 

cutthroat trout 

Oncorhynchus clarki 

pleuriticus Sensitive Yes 

Activities in EIS 

analysis area 

would have no 

effect on 

Colorado River 

system 

Amphibians 

Northern leopard frog Rana pipiens Sensitive No 

EIS analysis 

area is within the 

range of this 

species and 

suitable habitat 

may exist 

Great Basin 

spadefoot toad Spea intermontana Sensitive Yes 

EIS analysis 

area is outside of 

known range of 

this species 

Boreal toad Bufo boreas boreas Candidate/ 

Sensitive Yes 

EIS analysis 

area is below the 

elevation range 

of this species 

3.7.8.1 White­tailed Prairie Dog (BLM Sensitive)

In Wyoming, white-tailed prairie dogs inhabit grasslands and sparse shrublands east of the 

Continental Divide (Clark and Stromberg 1987). White-tailed prairie dogs feed on a variety of 

grasses, forbs and woody plants. Overgrazing by livestock may result in increased prairie dog 

density on favorable sites (Fitzgerald et al. 1994). 

White-tailed prairie dogs typically form loosely organized colonies or towns. Burrow densities in 

towns surveyed within the Pilot Project area ranged from 3.6 to 20.6 per acre (TRC 2000). Whitetailed prairie dogs are prey to a variety of predators including eagles, hawks, badgers, coyotes, 

foxes, black-footed ferrets and rattlesnakes (Campbell and Clark 1981). 

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White-tailed prairie dog towns are located throughout the EIS analysis area, particularly in the 

vegetative communities of low shrub/mixed grass, threadleaf sedge/mixed grass, mixed grass, 

and disturbed sites, as described in Section 3.6, Vegetation. See Figure 46, Mountain Plover 

and Prairie Dog Habitat. 

3.7.8.2 Black­footed Ferret (Federal Endangered)

Black-footed ferrets were historically distributed throughout the high plains of the Rocky Mountain 

and western Great Plains regions. Their distribution was closely tied to white-tailed and blacktailed prairie dogs, their principal prey. Prairie dog burrows were also used by ferrets for shelter 

and denning. 

Black-footed ferrets were considered extinct until a small population was discovered near 

Meeteetsee, Wyoming in 1981. Much of the current knowledge of this species is based on studies 

completed on the Meeteetsee population. Following an outbreak of distemper, all surviving ferrets 

were brought into captivity, and a captive breeding program was initiated (USFWS 2004). Since 

then, an experimental population of black-footed ferrets has been reintroduced in the Shirley 

Basin/Medicine Bow Special Management Area northeast of the Seminoe Road Project. The 

physical barrier imposed by Seminoe Reservoir and the Medicine Bow River precludes any 

potential movement of ferrets from this reintroduced population into the EIS analysis area. 

White-tailed prairie dog towns represent potential habitat for black-footed ferret in the EIS analysis 

area. According to USFWS guidelines (2004), white-tailed prairie dog towns or complexes greater 

than 200 acres in size represent potential habitat for black-footed ferrets. A town complex is 

defined as two or more neighboring towns each less than 7 kilometers (approximately 4 miles) 

from the other. A number of towns met these criteria within the Pilot Project and Pipeline Project 

areas and were surveyed for ferrets by TRC (2002a, 2002e). The results of these 2002 surveys 

were negative. 

3.7.8.3 Swift Fox (BLM Sensitive)

The swift fox resides in shortgrass and midgrass prairies over most of the Great Plains including 

central and eastern Wyoming (Clark and Stromberg 1987). The swift fox will also use agricultural 

lands and irrigated meadows. Swift foxes prey on a variety of small rodents, lagomorphs and 

birds. In many areas, cottontails and jackrabbits constitute the bulk of their diet (Fitzgerald et al. 

1994). 

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The EIS analysis area is near the periphery of the known range of the swift fox, but expanses of 

shortgrass prairie are generally lacking within the EIS analysis area. Swift fox has not been 

observed within or in the vicinity of the EIS analysis area (WNHP 2004). 

3.7.8.4 White­faced Ibis (BLM Sensitive)

The EIS analysis area is located within the breeding range of white-faced ibis, but suitable nesting 

habitat is essentially lacking. This species nests in small colonies in freshwater marshes or wet 

meadows. Backwater and associated riparian areas along the North Platte River within the EIS 

analysis area may provide marginal habitat for the white-faced ibis; however, the large annual 

water level fluctuations in Seminoe Reservoir preclude the development of suitable nesting habitat 

for white-faced ibis adjacent to reservoir shoreline. This species is most likely to occur within the 

EIS analysis area as occasional migrants or transitory birds in small wetlands surrounding stock 

ponds or in marshy areas along the North Platte River. 

3.7.8.5 Trumpeter Swan (BLM Sensitive)

No known trumpeter swan breeding areas exist in the EIS analysis area (Dorn and Dorn 1990), 

and suitable nesting habitat is lacking. Trumpeter swan are most likely to occur as occasional 

spring and fall migrants on the North Platte River and Seminoe Reservoir. 

3.7.8.6 Mountain Plover (BLM Sensitive)

The mountain plover was previously proposed as a federal candidate for listing as threatened or 

endangered, but its proposed listing has been withdrawn. Mountain plover is one of the few 

shorebirds that do not prefer habitats near or associated with water, but prefers to inhabit arid 

shortgrass prairie. Potential mountain plover habitat within the EIS analysis area includes low 

shrub/mixed grass, threadleaf sedge/mixed grass, mixed grass, disturbed sites and playas. See 

Section 3.6, Vegetation. Mountain plovers are relatively common in the low shrub/mixed grass 

habitats and in prairie dog towns. 

3.7.8.7 Bald Eagle (Federal Threatened, Proposed for Delisting)

Summer bald eagle nesting habitat consists of large trees, cliffs or sheltered canyons associated 

with preferred food sources that consist of fisheries or waterfowl concentration areas along large 

rivers, lakes or reservoirs. During the non-breeding season (fall and winter), bald eagles forage 

along rivers and over uplands with big game carrion or prairie dog populations. Winter roosting 

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November 2005 Draft Environmental Impact Statement

sites are generally large trees protected from the weather along open water portions of rivers or 

on lakes and reservoirs where waterfowl are available as prey. 

Potential bald eagle foraging, perching, and nesting habitat exists along the North Platte River. 

Bald eagles foraging along the river may occasionally fly over upland portions of the EIS analysis 

area. 

3.7.8.8 Ferruginous Hawk (BLM Sensitive)

The ferruginous hawk inhabits grasslands, shrublands, and steppe-deserts of the Western United 

States. During the winter months, they migrate to similar habitats in the southwestern United 

States and northern Mexico. Foraging habitat consists of non-forested, non-mountainous areas 

such as desert shrub and grassland communities. Nesting habitat consists of low shrub or 

grassland communities with isolated trees, bluffs, buttes, rock outcrop and open country with 

rolling topographic relief. This hawk nests on a variety of substrates including rock outcrops or 

pillars, high points on open ground, and low trees or shrubs. Because of their habit of nesting on 

or near the ground, nest sites are often vulnerable to predation. 

Carbon County contains one of the highest densities of ferruginous hawks in Wyoming. The BLM 

Rawlins Field Office and other entities have established a number of elevated nesting platforms in 

the region to improve ferruginous hawk nesting opportunities and nest security. Ferruginous hawk 

nests are scattered throughout the EIS analysis area, although many are currently inactive. Most 

of these nest sites are located on man-made rock pillars or natural rock outcrops. 

3.7.8.9 Peregrine Falcon (BLM Sensitive)

On August 25, 1999, the American peregrine falcon was “delisted” as a federally endangered 

species. The EIS analysis area is located within the nesting range of the American peregrine 

falcon. The peregrine's preferred nest sites are rugged, remote cliffs (100 to 300 feet in height) 

that usually overlook water, marshes or riparian areas where prey is abundant (USFWS 1984). 

Preferred hunting areas include cropland, meadows, river bottoms, marshes and lakes that attract 

abundant bird life. Peregrines prey on small to moderate sized birds such as blackbirds, doves, 

robins, flickers, jays, meadowlarks, waterfowl and pigeons, and they can travel up to 17 miles to 

hunt (USFWS 1984). 

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Potential peregrine falcon foraging, perching and nesting habitats within the EIS analysis area 

exist along the North Platte River, although there are no records of nesting use in this area 

(WNHP 2004). Peregrine falcons may forage along the river and occasionally fly over upland 

portions of the EIS analysis area. 

3.7.8.10 Greater Sage­grouse (BLM Sensitive)

Greater sage-grouse have declined throughout its range, although the causes of the decline have 

not been quantified (WGFD 2003). USFWS has reviewed petitions for listing the greater sagegrouse as threatened or endangered, but has determined that listing the greater sage-grouse is 

not warranted at this time (Federal Register 70(8): 2244-2249, 1/12/05). The WGFD has 

developed the Wyoming Greater Sage-grouse Conservation Plan (WGFD 2003) to identify 

reasons for the decline of sage-grouse and to increase the present distribution and abundance of 

sage-grouse in Wyoming. 

Sagebrush with interspersed diverse native grass and forb understory is key to sage-grouse 

habitat (WGFD 2003). Sagebrush provides forage and nesting, security and thermal cover for 

sage-grouse. During the summer, moist areas that support succulent herbaceous vegetation are 

used as brood rearing habitat. During the winter, sage-grouse feed on sagebrush leaves and 

buds, and require sagebrush above snow (WGFD 2003). 

Sagebrush habitat is available throughout the EIS analysis area, and open areas within the 

sagebrush vegetation serve as breeding areas (strutting ground or lek). A total of 10 active or 

historic sage-grouse leks are known to be located within the EIS analysis area, with an additional 

10 leks located within 2 miles of the EIS analysis area boundaries. See Figure 45, Wildlife Map. 

3.7.8.11 Long­billed Curlew (BLM Sensitive)

The EIS analysis area is located near the periphery of the breeding range of long-billed curlew. 

This Neotropical migrant winters along beaches and mudflats on the California coast and as far 

south as Honduras and Costa Rica (Ehrlich et al. 1988). This species nests in shortgrass prairie, 

rangeland, and meadows, usually near water. Meadows and grassland habitats along the North 

Platte River, Seminoe Reservoir, and stock ponds represent potential breeding habitat within the 

EIS analysis area. These species may also migrate through the EIS analysis area and utilize the 

shoreline areas of the North Platte River and the Seminoe Reservoir during their migration. 

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November 2005 Draft Environmental Impact Statement

3.7.8.12 Burrowing Owl (BLM Sensitive)

Burrowing owls are a migratory species in Wyoming and are known to occur in the EIS analysis 

area. This species resides in the state from early March through October, typically in grasslands 

and mountain parks in or near prairie dog towns. Abandoned prairie dog holes are used for cover 

and nesting, and burrowing owls hide in burrows when they feel threatened. Families of owls 

remain together in a prairie dog town until they migrate south to Mexico and Central America to 

spend the winter. 

3.7.8.13 Loggerhead Shrike (BLM Sensitive)

The loggerhead shrike is a summer resident in Wyoming and migrates to the southwestern United 

States and as far south as central Mexico in the winter (Ehrlich et al. 1988). This species prefers 

open country, thinly wooded, or scrubby land with clearings (Terres 1980). Robbins et al. (1989) 

indicate that this species has shown population declines over most of North America. Sagebrush 

and greasewood communities within the EIS analysis area represent suitable habitat for summer 

loggerhead shrike populations and this species was commonly observed during field surveys. 

3.7.8.14 Sage Thrasher, Sage Sparrow and Brewer’s Sparrow (BLM Sensitive)

These birds are summer residents in Wyoming and winter in the southwestern United States and 

Mexico. These birds breed in sagebrush habitats such as those found in the EIS analysis area. 

Field surveys documented the presence of sage thrasher and Brewer’s sparrow. 

3.7.8.15 Northern Leopard Frog (BLM Sensitive)

The northern leopard frog occurs in Wyoming along the banks and in the shallow water areas of 

marshes, ponds, streams, lakes and reservoirs. Water bodies with rooted aquatic or emergent 

vegetation are preferred (Baxter and Stone 1985). Backwater areas of the North Platte River and 

upland stock ponds with rooted emergent vegetation represent suitable northern leopard frog 

habitat in the EIS analysis area. Large water level fluctuations in Seminoe Reservoir preclude the 

development of suitable northern leopard frog habitat along the reservoir’s shoreline. 

3.7.8.16 North Platte River Species (Federal Threatened and Endangered)

No suitable habitat exists within or near the EIS analysis area for the whooping crane 

(endangered), least tern (endangered), pallid sturgeon (endangered), Eskimo curlew 

(endangered), and piping plover (threatened). However, important habitat areas do exist for these 

Seminoe Road Gas Development Project 3­67
Draft Environmental Impact Statement November 2005

species along downstream portions of the Platte River system, particularly in Nebraska. The 

USFWS requires Section 7 Consultations where federal actions in the Platte River system result 

in water depletions. 

3.8 Land Use

Dominant land uses within the region are agriculture (livestock grazing), recreation, mining, and oil 

and gas development. Specifics about land use within and adjacent to the EIS analysis area are 

set forth in Appendix E, Regional Activity. 

3.8.1 Private and Public Lands

Mixed surface ownership occurs within the 137,000-acre EIS analysis area as shown on Figure 2, 

Surface Ownership Map. Ownership assumes a “checkerboard” pattern of mostly federal 

(>49%) and private (>49%) control. State lands are less than 1% of the EIS analysis area. Within 

this checkerboard surface ownership, the general public does not typically have access to the 

BLM lands because the public needs permission to cross private surface. Although two-track 

roads crisscross the entire EIS analysis area, use of these roads is restricted, and public access 

is limited, in particular to the shoreline of the Seminoe Reservoir. 

3.8.2 Rangeland

The predominate land use activity within the EIS analysis area is livestock grazing. Portions of five 

BLM grazing allotments are contained within the EIS analysis area. See Figure 47, Grazing 

Allotments. Grazing management on BLM-administered lands is directed towards meeting and/or 

exceeding, “Healthy Rangeland Standards”. Presently, livestock grazing is permitted on all five 

allotments. Some range improvements, such as fencing and stock ponds, have been made to the 

BLM grazing allotments in this region. Table 3.8-1, Allotment Summary, displays permitted use 

and allotment management. 

3.8.3 Residential and Urban Land

Residential and urban lands are outside of the EIS analysis area, primarily concentrated in the 

towns of Rawlins, Sinclair and Hanna. The community known locally as the “Boat Club” is located 

adjacent to Seminoe Reservoir north of the EIS analysis area (Section 9, T24N, R84W). 

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November 2005 Draft Environmental Impact Statement

A few cabins and houses are located on privately owned surface north of the North Platte River in 

the EIS analysis area; these structures are used principally for recreational purposes. 

The “Miller Bend” development is a grouping of (5-20 acres) lots located in Section 17, T22N, 

R85W. To date, only one building and well permit application has been received in this platted 

development. 

1 Table 3.8-1, Allotment Summary

Allotment Name 

Ft. Steele 

Breaks 

North 

Walcott 

Quealey 

Block Seminoe 

Horseshoe 

Ridge 

Allotment Number 00816 00819 00820 10218 00807 

Total Allotment Size (acres) 18,946 70,680 54,262 157,703 44,036 

Allotment Size in EIS Analysis 

Area (acres)2 5,300 41,400 5,850 75,000 100 

Percentage of Allotment in EIS 

Analysis Area (%) 28% 59% 11% 48% >1% 

Total Animal Unit Month 

(AUMs)3 790 2,348 3,848 11,066 2,279 

Acres/AUM 23.98 30.10 14.10 14.25 19.32 

AUMs/Acre 0.042 0.033 0.071 0.070 0.052 

Class of Livestock Cattle/Sheep Cattle/Sheep Cattle/Sheep Cattle Cattle/Sheep 

Grazing System Management Deferred 

Rotation 

Year Long 

Permit 

Year Long 

Permit 

Deferred 

Rotation 

Year Long 

Permit 

Current Number of Cattle/Sheep 

Permitted4 

67 Cattle 

335 Sheep 

425 Cattle 682 Cattle 1,808 Cattle 250 Cattle 

1,249 Sheep 

Notes: 

1. For location of allotments, see Figure 47, Grazing Allotments. 

2. Acreage calculations for allotments within EIS analysis area assume an estimated 9,350 acres for the 

Seminoe Reservoir at the high water level within the EIS analysis area. 

3. AUMs = Animal Unit Month: the amount of forage required by an “animal unit” grazing for one month. The 

standard animal unit is defined as one mature 1,000 pound cow with a calf, or equivalent, and is based upon 

average daily forage intake of 26 pounds dry matter per day. That consumption, combined with a factor for 

tramping and waste of about 25%, results in an estimate of about 1,000 pounds of dry matter from forage to 

supply one animal unit each month. 

4. Animal numbers may vary based on operator’s annual application for use. 

Source: BLM 2004, Murray personal communication 

3.8.4 Mining

Surface and underground coal mining activities have and continue to be conducted on lands 

within and adjacent to the EIS analysis area. Much of the land disturbed by these coal mining 

activities has been reclaimed. The mines are now either closed, conducting reclamation work, or 

operating in a reduced capacity. See Appendix E, Regional Activity. 

3.8.5 Recreation

No developed recreation facilities are operated by the BLM or the State of Wyoming within the EIS 

analysis area; however, developed recreation sites are located on Seminoe Reservoir north of the 

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EIS analysis area and on the North Platte River (Dugway Recreational Site) south of the EIS 

analysis area. Hunting is the primary dispersed recreation activity within and adjacent to the EIS 

analysis area, however, much of the hunting within the EIS analysis area is conducted through 

outfitters. Another popular recreational activity in the EIS analysis area is fishing, both on Seminoe 

Reservoir and on the North Platte River. See Section 3.11, Recreation and Appendix E, 

Regional Activity. 

3.8.6 Oil and Gas

The Seminoe Road Pilot Project is the principal oil and gas development within the EIS analysis 

area; its target is coalbed natural gas. Attempts by the Proponent and others to develop 

conventional oil and gas resources within and immediately adjacent to the EIS analysis area have 

not been successful to date. Numerous exploration boreholes and wells have been drilled, but no 

economic oil and gas reserves have been discovered. One gas well, located on Windy Ridge 

north of the EIS analysis area, is reported to have been productive, but it is currently capped. 

(BLM, personal communication 2004a). 

Oil and gas development and operations in the general area are discussed in Appendix E, 

Regional Activity. 

3.8.7 Utilities

A WAPA 69kV transmission line and a Conoco high-pressure oil pipeline cross the EIS analysis 

area. See Appendix E, Regional Activity. 

3.8.8 Land Use Plans and Policies

The EIS analysis area is zoned ranching, mining and agriculture and is located within an area 

recommended for oil and gas exploration and development (Carbon County Land Use Plan, 

Chapter 7, June 16, 1998). 

The BLM Great Divide Resource Area RMP (dated November 1990) states that the area 

encompassed by the EIS analysis area is open to oil and gas leasing and operations. 

3.9 Noise

Noise is defined as unwanted, disturbing sound. The impact of a noise source depends on the 

levels and characteristics of the background sound, as well as the characteristics of the sound. 

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Sound is transmitted through the atmosphere as low-intensity pressure waves. People can detect 

and respond to a wide range of sound intensities and frequencies. 

The logarithmic decibel scale (dB) is used to indicate the intensity of sound. To measure sound on 

a scale that approximates the way people hear, more emphasis must be placed on those sound 

frequencies (or pitch) that people hear. EPA recommends the use of “A-weighted” sound pressure 

levels, expressed as A-weighted decibels or dBA, for analyzing community noise issues. 

Table 3.9-1, Typical Range of Common Sounds, shows the range of dBA sound intensities that 

are produced by various noise sources. The threshold of human hearing is 0 dBA. Quiet whispers 

and birdcalls produce about 25 to 40 dBA. Ambulance sirens can reach 100 dBA, while a military 

jet takeoff with an after burner can exceed 140 dBA. 

Table 3.9-1, Typical Range of Common Sounds 

Noise Source 

(at a given distance) 

A-Weighted Sound Level 

(dBA) 

Military jet take-off with after burner (50 feet) 140 

Commercial jet take-off (200 feet) 120 

Ambulance siren (100 feet) 100 

Power lawn mower (3 feet) 100 

Motorcycle (25 feet) 90 

Propeller plane flyover (1,000 feet) 90 

Diesel truck, 40 mph (50 feet) 90 

Garbage disposal (3 feet) 80 

Passenger car, 65 mph (25 feet) 70 

Vacuum cleaner (3 feet) 70 

Normal conversation (5 feet) 60 

Light traffic (9,100 feet) 50 

Birdcalls (distant) 40 

Soft whisper in quiet room (5 feet) 30 

Recording studio 20 

Threshold of hearing 0 

Because decibels are a logarithmic scale, a doubling of the sound pressure corresponds to a 

noise increase of 3 dBA. For example, a single bulldozer typically produces about 85 dBA of noise 

at a distance of 50 feet from the bulldozer. Therefore, two identical bulldozers operating side-byside (with each bulldozer producing 85 dBA) produce a theoretical noise level of 88 dBA. 

Many factors determine whether an increase in the noise level above the existing background is 

“audible.” The most important factor is the nature of the new noise source as compared to the 

nature of the background noise. In the case of the proposed Seminoe Road Project, the noise 

caused by drilling activities would be different from the rural background sounds, so relatively 

small increases in noise levels caused by the mechanical equipment would be noticeable. 

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The EIS analysis area is unpopulated and relatively remote. There are no permanently occupied 

residences or human receptors in the vicinity of the project area. The closest site with daily, yeararound human activity is the “Boat Club” area, which is located approximately 1 mile north of the 

northern boundary of the EIS analysis area (Section 9, T24N, R84W). An undeveloped fishing site 

known locally as Coal Creek Bay is used by local fishermen. This site is located within the project 

boundary in Section 12, T24N, R85W. These sites, along with the Seminoe Reservoir, experience 

year-round daily recreational use. 

In general, the background noise of the EIS analysis area would be relatively quiet, with wind 

noise being a principal sound source. The existing Pilot Project creates some noise, as a result of 

propane-powered water pumps. In addition, traffic along Carbon County Road 351 (Seminoe 

Road) would generate noise. There could also be localized noise from all-terrain vehicles (ATVs), 

dirt bikes, and/or four-wheel drive vehicles using the two-track roads in the area, as well as the 

occasional over flight by jet aircraft. In addition, recreationists on Seminoe Reservoir and at 

shoreline campgrounds would create noise with powerboats, jet skis, trailers, stereos, parties, and 

bug zappers. 

Neither Carbon County, the state of Wyoming nor the BLM has noise regulations that would affect 

natural gas development and operations in the EIS analysis area. In 1974, the EPA established a 

24-hour average level of 55 dBA as a guideline threshold for acceptable environmental noise. This 

level is used as a general basis for evaluating effects from noise when no other local, county or 

state standards have been established. Typically, this guideline level would be directed at areas 

where people would live and work, not the remote region found in the EIS analysis area; however, 

this 55 dBA threshold level would serve as a general target level by which to assess noise levels 

at the Seminoe Road Project. 

OSHA regulations require worker hearing protection when noise levels exceed 90 dBA. See Table 

3.9-2, Permissible Occupational Noise Exposures. 

3.10 Cultural Resources

3.10.1 Introduction

Cultural resources on public lands, including prehistoric and historic properties, are protected by 

various laws and regulations. The most notable federal regulation is the National Historic 

Preservation Act (NHPA) of 1966, as amended with its implementation regulations contained in 36 

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1 Table 3.9-2, Permissible Occupational Noise Exposures

Sound Level 

(dBA) 

Duration 

(hr/day) 

90 8 

92 6 

95 4 

97 3 

100 2 

102 1.5 

105 1 

110 0.5 

115 <0.25 

Notes: 

1. U.S. Department of Labor, “Occupational Noise 

Exposure,” Code of Federal Regulations, Title 29, Part 

1926. 

CFR 800. The laws and regulations require that any proposed activities, which disturb public 

lands, take into consideration the effects of the activities on significant cultural resources. 

herefore, cultural resources within the disturbed area boundaries of the Seminoe Road Project 

must be identified and evaluated. The laws and regulations require that appropriate mitigation 

measures be taken to prevent, minimize, or mitigate adverse effects to cultural resources included 

in, or eligible for, the National Register of Historic Places (NRHP). 

The existing cultural resource database for the Seminoe Road Project analysis area indicates that 

roughly 16% of the area has been inventoried for cultural resources, and 277 sites have been 

recorded. Based on the existing inventory, 44% of the recorded sites are eligible or recommended 

to be eligible for the NRHP, while 40% are ineligible and 16% remain unevaluated. A description 

of these existing inventoried sites is discussed later in this section. Potential for impacts to cultural 

resource sites and the procedures for analyzing the potential impacts are discussed in Section 

4.10, Cultural Resources. 

This section of the Seminoe Road EIS contains a summary of the cultural chronology of the 

general region, a summary of the previous cultural resource investigations, a description of 

existing cultural resources and the potential for new cultural resources in uninventoried areas. 

3.10.2 Cultural Chronology of the General Region

Archaeological investigations in the Wyoming Basin indicate that this region was occupied by 

prehistoric people for more than 11,000 years, from the Paleoindian through Protohistoric periods. 

The Wyoming Basin prehistoric chronology, with periods, phases, and ages is presented in Table 

3.10-1, Prehistoric Chronology of the Wyoming Basin. 

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Table 3.10-1, Prehistoric Chronology of the Wyoming Basin 

Period Phase Age (B.P.)

1 

Paleoindian NA 12000 – 8500 

Archaic 

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 NA 300/250 - 150 

Note: 

1. B.P. = Before Present 

The following discussion of the cultural chronology of the Wyoming Basin includes sites that are 

not necessarily located within the Seminoe Road Project analysis area. 

3.10.2.1 Paleoindian Period

The oldest period for which there is solid archaeological evidence is the Paleoindian, beginning 

circa 12,000 years before present (B.P.) and ending around 8500 B.P. This is the transition period 

from the periglacial conditions of the Wisconsin Ice Advance during the terminal Pleistocene to 

the warmer and drier climate conditions of the Holocene. A savanna-like environment with higher 

precipitation than occurs today was prevalent in southwest Wyoming. Paleoindian sites are 

relatively rare, although isolated surface finds of Paleoindian projectile points are not uncommon 

and suggest that site preservation may be a major factor affecting the number of known sites. The 

Paleoindian tool assemblage includes lanceolate points, gravers, and end-scrapers. Within the 

Wyoming Basin, about twenty sites with Paleoindian components have been excavated, including 

the Seminoe Beach Site (48CR1166), located about 1 mile north of the EIS analysis area. 

3.10.2.2 Archaic Period

Settlement and subsistence practices in the Wyoming Basin remained largely unchanged from the 

end of the Paleoindian Period through the Archaic Period. In some places these practices 

continued until at least the introduction of the horse and historic contact. Reduced precipitation 

and warmer temperatures prevailed until 8500 B.P. This environmental change led to a pattern of 

broad spectrum resource exploitation associated with more diverse subsistence and settlement 

practices. The Archaic Period is divided into the early and late periods, which are subdivided into 

the Great Divide and Opal and the Pine Spring and Deadman Wash phases, respectively. Large 

side- and corner-notched dart points were used for hunting. The presence of groundstone 

implements suggests a greater use of plant resources during the Archaic Period. Faunal 

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November 2005 Draft Environmental Impact Statement

assemblages from Archaic components document increased use of small animals. Large sidenotched points from areas adjacent to the Wyoming Basin occurred as early as 7000 B.P. Within 

the Wyoming Basin at least 30 sites with Archaic Period components have been excavated. At 

least three such sites are in the general vicinity of the EIS analysis area, including the Scoggin 

site, the Muddy Creek site, and the Shoreline site (48CR122). The Shoreline site located within 

the Seminoe Road Project analysis area has been radiocarbon dated to 5000 – 5220 B.P. 

The remains of dwelling structures referred to as houspits also appear during this period. At least 

twenty sites with housepits are known in Carbon County. Housepits from this period generally 

consist of semi-subterranean dwellings with interior hearths, storage pits and other interior 

features. At least one housepit was identified during excavation of the Shoreline site, which is 

located within the Seminoe Road Project analysis area. 

3.10.2.3 Late Prehistoric Period

The Late Prehistoric Period in the Wyoming Basin dates between 2000/1800 B.P. and 300/250 

B.P. and is subdivided into the Uinta and the Firehole phases. Large scale seed processing and 

an increase in the number of cultural features is noted in the Late Prehistoric Period, as is the 

presence of pottery and the introduction of bow and arrow technology. A characteristic of the Uinta 

phase is clusters of semi-subterranean structures dating to 1050 B.P. In the southern Wyoming 

Basin, west of the current EIS analysis area, at least two different types of structures have been 

identified; a more substantial, cold weather habitation structure at the Nova site and a less 

substantial, warm weather structure serving more as a windbreak at the Buffalo Hump site. 

The Firehole phase is distinguished from the preceding Uinta phase by a dramatic decline in 

components that have been radiocarbon dated to that phase, possibly reflecting a decline in 

population density. Several sites within the EIS analysis area have Late Prehistoric components 

as well as Archaic components. Two of these sites are the Seminoe Beach and Shoreline sites 

that were previously described in Section 3.10.2.2, Archaic Period. 

3.10.2.4 Protohistoric Period

The Protohistoric Period generally begins after 300 years B.P. with the introduction of European 

trade goods into the area, and ends with the development of the Rocky Mountain fur trade 

approximately 150 years ago. The Wyoming Basin was the heart of Shoshone territory during this 

period although there were occasional forays into the area by other peoples such as the Crow and 

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the Ute. The most profound influence on native cultures during this time was the introduction of 

the horse, enabling Native Americans to expand their range. All forms of rock art denoting horses, 

metal projectile points and other metal implements and other Euro-American trade goods are 

associated with the Protohistoric Period. Metal projectile points associated with this period have 

been recovered from both surface and subsurface excavations in the Wyoming Basin. At least ten 

sites with Protohistoric components have been identified within the EIS analysis area. 

3.10.2.5 Historic Period

Historic use of the Wyoming Basin has been influenced largely by the exploitation of various 

natural resources, including rangeland, minerals, timber, and surface water. Areas with difficult 

terrain and limited or no exploitable natural resources have remained largely unsettled and have 

been used only for limited ranching. (See Table 3.10-2, Historic Chronology of the Wyoming 

Basin). 

Table 3.10-2, Historic Chronology of the Wyoming Basin 

Phase Age A.D. 

Pre-Territorial 1842-1868 

Territorial 1868-1890 

Expansion 1890-1920 

Depression 1920-1939 

Modern 1939-Present 

The Pre-Territorial and Territorial phases are represented to the south of the EIS analysis area by 

the Transcontinental Railroad and Fort Fred Steele, both of which date to the 1860s. 

Homesteading as well as sheep and cattle ranching began in this area during the Territorial phase 

in the 1870s. The expansion, depression and modern phases are dominated within the EIS 

th analysis area by a coal mining theme, which began in the late 19 Century and continues to the 

present. The modern phase includes continued ranching as well as the 1930s era construction of 

Seminoe Reservoir and by ongoing coal and oil and gas developments. 

3.10.3 Summary of Previous Cultural Resource Investigations

Research conducted through the Wyoming Cultural Records Office provided information on the 

previous archaeological work and recorded cultural resources sites within the EIS analysis area. A 

total of 136 cultural resource investigations have been conducted in the past within the analysis 

area, covering 22,434 acres (or 16% of the analysis area). Nearly all of these investigations (130) 

have been Class III Intensive Inventories. The other six investigations consisted of Class II 

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November 2005 Draft Environmental Impact Statement

Sampling Inventories, test excavations, and construction monitoring. All past investigations were 

conducted between 1975 and 2002. Past investigations were conducted to provide NHPA 

compliance for various projects including coal mining, seismic exploration, oil and gas well and 

pipeline construction, access roads, and transmission lines. The majority of these cultural 

resource investigations have covered relatively small areas, mostly in the 20 to 50 acre range, 

including 10 acre blocks for well sites and 100 foot corridors for seismic lines, access roads, and 

pipelines. Several larger block investigations have been conducted for coal mining projects, 

involving between 1,000 and 4,800 acres per inventory. 

3.10.3.1 Summary of Recorded Cultural Resources

A total of 277 sites have been recorded within the EIS analysis area, consisting of 262 prehistoric 

sites (95%), eight of which have historic components and fifteen historic sites (5% of total). Most 

of the prehistoric sites are described as prehistoric campsites with lithic scatters and/or hearths. 

Tipi ring or stone circle sites, some of which can also be interpreted as campsites, are the second 

most numerous prehistoric site types comprising 11% of the total prehistoric sites. The remaining 

14% of the total prehistoric sites consists of one large lithic procurement site, two human burials, 

three bison/processing sites, several cairn sites and one housepit site. 

3.10.3.2 National Register of Historic Places Sites

The Wyoming SHPO lists 23 (8%) of the 277 recorded cultural resource sites as eligible for the 

NRHP. An additional 100 sites (36%) have been field evaluated as eligible but presently lack 

SHPO concurrence. The SHPO database lists 111 sites (40%) as ineligible for the NRHP. The 

remaining 43 sites (16%) are unevaluated for the NRHP. However, those sites, which are 

unevaluated, that are managed as though they are eligible to the NRHP until they are formally 

evaluated; at which time they are managed according to the formal eligibility determination. 

3.10.3.3 Prehistoric Sites

Prehistoric open campsites comprise the majority of the total cultural resource sites within the 

Seminoe Road Project analysis area, as shown in Table 3.10-3, Summary of Prehistoric and 

Historic Sites Within the Seminoe Road Analysis Area. Ninety percent of the prehistoric sites 

in this category contain hearth remains, and most also contain lithic reduction debris and/or 

groundstone. 

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Table 3.10-3, Summary of Prehistoric and Historic Sites Within the Seminoe Road Analysis 

Area 

Site Type Number of Sites Percent of Site Type 

Prehistoric Sites 

Open campsite, with hearths and/or 

flaked stone/groundstone lithics 193 71 

Tipi ring/stone circle sites 29 11 

Lithic scatters 34 12 

Sites with human remains 2 0.7 

Kill/butchering sites 3 1.0 

Housepit sites 1 0.4 

Total Prehistoric Sites 262 

Historic Sites 

Mine Sites 4 1.4 

Stockherding camps 5 1.8 

Historic transmission line segments 3 1.0 

Historic trash scatters 3 1.0 

Total Historic Sites 15 

Notes: 

Site types and sites containing less common/rare components and features (e.g. ceramics and 

stone circles,) are listed separately. 

Prehistoric campsites are present throughout the Wyoming Basin and generally are interpreted as 

representing short-term activities (lithic reduction, food preparation, and short-term occupation). 

One lithic procurement site (48CR2680) has been recorded in the EIS analysis area. Lithic 

procurement sites or quarries occur where raw materials such as cherts and quartzite were 

obtained from natural geologic deposits and initially processed for use in making flaked stone 

tools. Ceramics are rare in the project area. Only three sites containing pottery have been 

recorded, all of which have been identified as Shoshonean. Two sites with steatite have also been 

identified. These materials are generally associated with the Uinta phase of the Late Prehistoric 

Period. Also, Late Prehistoric glass trade beads have been identified at three sites. As noted 

earlier, one site within the EIS analysis area contained at least one semi-subterranean housepit, 

apparently dating to the early portion of the Late Prehistoric Period. 

Two bison kill/butchering sites, 48CR74 and 48CR4112 have been recorded within the project 

analysis area. Site 48CR74 was reported as a bison trap, located at the head of a canyon. One or 

more hunting blinds and several stone circles were associated with this discovery. Site 48CR4112 

was described as a butchering site, located on a river terrace, and containing a quantity of bison 

bone and hearth remains. 

A few sites located within and immediately surrounding the EIS analysis area have been identified 

as being sensitive or sacred to Native Americans. These sites may include human burials, some 

rock alignments, and rock art. Consultation with appropriate Native American tribes concerning 

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November 2005 Draft Environmental Impact Statement

these areas of sacred or sensitive significance for traditional, cultural, or religious purposes will 

occur in accordance with the NEPA, the NHPA, the Federal Land Policy and Management Act, the 

American Indian Religious Freedom Act, and Executive Order 13084 on Consultation and 

Coordination with Indian Tribal Governments. Please refer to Section 4.10.5, Native American 

Consultation. Two sites listed as human burials have been recorded within the project site. A 

bundle burial, site 48CR933, was excavated by the University of Wyoming in the 1970s. No date 

was given for this site, although the bone beads associated with it suggest that it may date as 

early as the Late Archaic Period. Another burial, site 48CR405, was recorded in the early 1980s 

within the project area. This site was reported as a rock crevice burial, heavily disturbed and 

containing only two human bones. Glass trade beads and a small side-notched projectile point 

associated with this burial suggest a Late Prehistoric affiliation. Only three of the known sites 

within the EIS analysis area contain rock alignments, which may be the remains of disturbed tipi 

rings/ceremonial features, or linear alignments possibly associated with hunting. Rock art, which 

is primarily composed of pictographs or petroglyphs has not been identified within the project area 

boundaries. 

A number of tipi ring or stone circle sites were identified in the database for the EIS analysis area. 

In addition to their presumed use to anchor hide covered tipis, stone circle sites may also have 

Native American religious significance. 

3.10.3.4 Historic Sites

There are 15 historic sites that have been formally recorded within the EIS analysis area. Four of 

the historic sites are described as mines, five are sheep or cattle herder’s camps, three are 

segments of an historic transmission line, and the remaining three are historic trash scatters. 

According to the 1883-1884 GLO Plats for the EIS analysis area, there appears to be two historic 

ranches also located within the project area. However, neither of these former ranches have been 

formally recorded and therefore are not included in the fifteen historic sites. It does appear 

however, that one of these ranches, the “Dorrety’s Ranch” was probably covered by water when 

the Seminoe Dam was constructed. 

The four mines that have been formally recorded consist of two mines described as gold mines 

and two described as “wagon” mines. The gold mines were reportedly operated sporadically 

between circa 1900 and as late as the 1950s era. The wagon mines were actually small coal 

mines and were only used by individual ranchers to obtain fuel for their own use and were fairly 

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th th common in the late 19 -20 Century era. The coal mines were generally located on the surface 

where the coal outcropped. They were mostly on public domain and were usually operated 

informally without legal title to the minerals. 

In addition to the fifteen recorded historic sites, the 1983-1984 GLO Plats show approximately 

eight historic wagon road segments, none of which have been formally recorded. One segment 

bears the name “Ferris” while the rest are unnamed. A few of these roads appear to roughly 

correspond to unimproved roads shown on the current quadrangle maps and at least one of these 

wagon roads is currently an improved county road. These wagon roads apparently served mostly 

local uses. There are no immigrant trails or other known historically-significant trails within the EIS 

analysis area. 

3.10.3.5 Excavated Sites

Archaeological excavations have been conducted at a number of sites both within the EIS 

analysis area and the surrounding area. Excavated sites within the project area include the 

Shoreline site and site 48CR4112. Both of these are prehistoric campsites with hearths and 

butchered bone and both are located within about one-half mile of the North Platte River or 

Seminoe Reservoir. Excavated sites outside of the Seminoe Road analysis area but within 1 to 4 

miles of the project boundaries include the Seminoe Beach site and the Scoggin site and several 

sites in the Seminoe coal mine area located east of the project. The Seminoe Beach site has 

yielded Hell Gap, McKean, and later artifacts demonstrating occupation from the late Paleoindian 

through the late Prehistoric periods. The Scoggin site is an Early Archaic bison kill/butchering site 

with McKean artifacts. 

3.10.4 Site Frequency and Distribution

Based on the existing inventory in the EIS analysis area (22,434 acres inventoried) and the 277 

previously recorded sites, a site density of 0.01 sites/surveyed acre or one site per 81 acres can 

be assumed. Projecting this average to the entire EIS analysis area, it could be assumed based 

on the existing data that an additional 1,400 sites could occur in the EIS analysis area. 

3.10.5 Archaeologically Sensitive Areas

Archaeologically sensitive areas within the EIS analysis area would include the North Platte River 

valley and its adjoining terraces, bluffs, and side ravines, as well as its larger tributaries. Existing 

data for these areas demonstrate a high potential for significant sites, including but not limited to 

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November 2005 Draft Environmental Impact Statement

open campsites, lithic scatters, and kill/butchering sites. Because of the deeper soil depth in the 

alluvial depositional areas, there is potential for undisturbed archaeological sites from the 

Paleoindian through the Protohistoric periods. Areas of stabilized dunes and sand sheets also 

have potential for sites of these types. Additionally, most of the prominent topographic features, 

including hills and ridges such as the Cedar Ridge in the southern portion of the EIS analysis area 

may have relatively higher archaeological potential, especially for ceremonial sites. Areas 

containing surface deposits of siliceous lithic materials have potential for lithic procurement/quarry 

sites. Prehistoric campsites and lithic scatters may also occur in proximity to playa depressions 

and areas of more open, flat lands such as in the central portion of the EIS analysis area, south of 

the North Platte River. 

3.10.5.1 Topography and Physiography Associated With Known Sites

The distribution of cultural sites within the EIS analysis area has been influenced by various 

environmental conditions, including topography, physiography, proximity to reliable water sources, 

and soil deposition, all of which are known to be factors in archaeological site formation and 

preservation. The known concentration of sites along the North Platte River suggests a 

preference for the floodplain and terrace areas, possibly related to higher concentrations of game 

and/or other food resources. Similarly, a relatively high number of sites occur in the stabilized 

dune formations as well as draws, which provide additional hunting opportunities. At least two 

bison kill sites are known in these areas. Several of the previously recorded cultural sites were 

discovered on relatively flat areas and in areas where soils averaged plus or minus 50 centimeters 

in depth. Nearly a third of the EIS analysis area has slopes generally less than 13 degrees and 

about half the project area has soils averaging greater than 50 centimeters. Areas with the 

deepest soils generally occur on the terraces, fans, floodplains and bottomlands and to some 

extent in Aeolian deposits. The eroded soils, which occur in about 25% of the EIS analysis area, 

and specifically in the northwestern portion, may be a factor in exposing buried archaeological 

sites. Based on the favorable topography, the grazing potential, and the known mining and 

ranching activities in the area, it can be assumed that the potential exists for more historic sites, 

including ranching and homestead structural remains, and adits and small surface coal mining 

pits. 

Although there is no definitive means to accurately project how many and what typed of resource 

sites may be contained within the EIS analysis area, existing information on known recorded sites 

can be used and projected to areas within the project boundaries that have not been inventoried. 

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This includes using existing site frequency and distribution information, as well as knowledge of 

archaeologically sensitive areas associated with known sites and projecting this information to 

unknown areas within the project boundaries. 

3.11 Recreation

There are no developed recreation facilities within the EIS analysis area. Recreation in the area is 

dispersed in nature, except at Seminoe State Park (and its associated facilities) and at the BLM 

Dugway Recreation Site. 

The dominant dispersed recreation activity in the EIS analysis area is hunting, which mainly 

occurs during the fall hunting seasons. Due to the checkerboard land ownership patterns, most 

hunters access the area only by permission from the private landowners. Some landowners also 

have agreements allowing licensed outfitters to use private lands. Without landowner permission, 

hunters can use BLM administered lands with public access, but they cannot use private land. 

Other dispersed recreation in the EIS analysis area includes boating (on Seminoe Reservoir), 

fishing, driving for pleasure and sight-seeing, horseback riding, target shooting, partying, camping 

and hiking. Like hunting, dispersed recreational access is limited by the checkerboard land 

ownership pattern. 

Approximately 9 miles of the Seminoe Road (Carbon Country Road 351) passes through the EIS 

analysis area (see Figure 1, General Location Map). The BLM has designated the Seminoe 

Road from Sinclair to Alcova as a “National Back Country Byway.” The BLM uses this designation 

to inform the public of roadways that provide visitors and recreationists an opportunity to see 

historic, scenic or unique natural environments. Travelers on Seminoe Road would have the 

opportunity to observe wildlife (antelope, mule deer, bighorn sheep, golden eagles and 

ferruginous hawks). The road crosses the rugged Seminoe Mountains and accesses the Miracle 

Mile, a blue-ribbon trout fishery on the North Platte River. North of the EIS analysis area, the road 

passes by huge sand dunes, which are part of the Killpecker Sand Dunes, a dune field which 

reaches from western Wyoming into Nebraska. 

In winter, the area lacks sufficient snow to be desirable for snow-shoeing, cross-country skiing or 

snowmobiling; however, ice-fishing is a popular activity on Seminoe Reservoir, particularly at Coal 

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November 2005 Draft Environmental Impact Statement

Creek Bay, an arm of Seminoe Reservoir that is within the project area. It is popular for bank and 

boat fishing, as well. 

Developed recreational areas outside of the EIS analysis area include (see Figure 19, Regional 

Activity): 

� Seminoe State Park; 

� The Miracle Mile; and, 

� Dugway Recreation Site. 

Seminoe State Park is a developed park managed by the State of Wyoming, and this park 

includes Seminoe Reservoir and facilities for camping picnicking, fishing, boating and water 

skiing. Primitive camping is allowed along the shoreline. The reservoir is approximately 20,300 

acres in size with about 180 miles of shoreline. 

The Miracle Mile is a 5 1⁄2-mile stretch of blue ribbon trout fishing stream located below the Kortes 

Dam north of the project site. The Miracle Mile is a popular fishery, where non-locals generally 

outnumber locals. The Bureau of Reclamation manages the recreation at the Miracle Mile area; 

however, this agency does not keep daily user visit counts or visitor days. Traffic counts 

immediately adjacent to the Miracle Mile reveal that 43,400 vehicles passed through this area in 

2003, although some of these may not have been recreational visitors. 

The Dugway Recreation Site is located on Seminoe Road adjacent to the North Platte River about 

3/4 mile southwest of the EIS analysis area boundary. It is available for day and overnight use. 

Facilities include a campground, a picnic area, a toilet and a water well. 

3.12 Transportation

The transportation analysis for the Seminoe Road Project includes I-80, Wyoming State Highway 

30, County Road 351 (known locally as the “Seminoe Road”), and the roads within the EIS 

analysis area. The roads within the region are shown on Figure 1, General Location Map. 

Traffic loads/traffic counts are identified as average daily traffic (ADT). ADT is defined as the 

measure of traffic over a 24-hour period and is determined by counting the number of vehicles 

passing a specific point on a particular road from either direction. 

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The Wyoming Department of Transportation estimates ADT values based on actual traffic counts 

made at various locations along federal, state and county roads. See Table 3.12-1, Traffic 

Counts for 2003. 

1 Table 3.12-1, Traffic Counts for 2003

Location2 Average Daily 

Traffic 

Estimate (%) of Commercial 

Trucks (greater than 10,000 

lb-gross vehicle weight) 

Interstate 80 at Walcott 11,540 54% 

Interstate 80 at Sinclair 12,410 53% 

Interstate 80 at Rawlins 11,620 54% 

Highway 30 (287) at Walcott, just north of Interstate 80 1,200 22% 

Highway 130, just south of Interstate 80, connecting to 

Saratoga 1,390 10% 

Highway 72, just north of intersection with Interstate 80 

connecting to Hanna 1,560 4% 

Highway 72, just south of intersection with Interstate 80 

connecting with Elk Mountain 290 14% 

County Road 351 (Seminoe Road) at Sinclair 308 4% 

County Road 351 at North Platte River (Miracle Mile) 118 Not available 

Notes: 

1. Traffic counts based on 2003 data obtained from the Wyoming Department of Transportation (WDOT, 2003) 

2. See Figure 1, General Location Map and Figure 19, Regional Activity. 

3.12.1 Interstate 80

I-80 is a major U.S. highway that traverses Wyoming from east to west. It serves as a main 

commercial truck route in the central Rocky Mountain region and over 50% of the traffic on I-80 in 

Carbon County, Wyoming, is 18-wheelers. See Table 3.12-1, Traffic Counts for 2003. 

I-80 is an asphalt and concrete, all-weather four-lane highway. In Carbon County, this highway is 

generally flat. This highway provides exit access to the communities of Rawlins, Sinclair, and 

Walcott. 

3.12.2 Highway 30 (287)

Highway 30 (287) is an asphalt, all-weather two-lane highway. In Carbon County, this road 

intersects with I-80 at Walcott and generally traverses the county in an east-west direction, 

passing south of Hanna but through Medicine Bow. Before the construction of I-80, Highway 30 

(287) was the primary east-west highway in Carbon County serving commercial, tourist and local 

traffic. Today, the role of this road as a major commercial routing is greatly reduced; however, 

during extreme winter conditions (snow storms, ground blizzards), Highway 30 (287) is sometimes 

used as an alternate for I-80 between Laramie and Walcott. 

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3.12.3 Highway 72

Highway 72 is an asphalt, all weather two-lane highway. North of I-80, this road connects with 

Hanna. South of I-80, it connects with Elk Mountain. Highway 72 is principally used by local 

residential and commercial traffic. 

3.12.4 Highway 287

Highway 287 is an asphalt all weather two-lane highway that traverses north-south in Carbon 

County. The portion of Highway 287 north of Rawlins is a primary route for local and commercial 

traffic to the communities of Lander, Riverton and Casper. Tourists also utilize this road for 

access to the Grand Teton and Yellowstone National parks. 

3.12.5 Highway 130

Highway 130 is an asphalt, all-weather two-lane highway. In Carbon County, this road intersects I80 near Walcott and traverses to the south to connect with Saratoga. South and east of Saratoga, 

Highway 130 passes through the Medicine Bow National Forest, crosses over Snowy Range Pass 

(at elevation of 10,847 feet), passes through the community of Centennial, and eventually 

connects to Laramie. 

3.12.6 County Road 351 (Seminoe Road)

Carbon County Road 351 (Seminoe Road) originates in Sinclair, bisects the EIS analysis area in a 

general north-south orientation, and provides access to Seminoe Reservoir and “Miracle Mile” on 

the North Platte River, then continues to Alcova, where it intersects State Highway 220 (the main 

road to the city of Casper). 

From Sinclair through the EIS analysis area, the Seminoe Road is an asphalt, all-weather twolane highway. Recent construction and paving have greatly improved the condition of the road 

within and south of the EIS analysis area. Seminoe Road has been designated a National Back 

Country Byway by the BLM (see Section 3.11, Recreation). 

Approximately 10 miles north of the northern boundary of the EIS analysis area, the asphalt 

pavement ends, and the Seminoe Road becomes a graveled all-weather road. 

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3.12.7 Existing Roads Within EIS Analysis Area

An estimated 300 miles of two-track roads currently exist within the EIS analysis area. Most of 

these roads are unimproved and inaccessible during wet periods and often during winter months. 

However, of this total, nearly 7 miles of all-weather gravel roads service the existing wells at the 

Pilot Project, and an estimated 10 miles of improved gravel roads provide access to the area 

north of the North Platte River in the southwest corner of the EIS analysis area. 

Given the “checkerboard” surface land ownership pattern of the EIS analysis area (see Figure 2, 

Surface Ownership Map), the public has limited access to the project area. Although roads on 

BLM-administered lands are generally open to the public, these roads are typically closed to public 

access once they cross onto the privately-owned land surface. 

3.13 Visual Resources

Broad stretches of moderate to flat topography characterize the majority of the EIS analysis area, 

although the landscape is periodically interrupted with rock outcroppings and eroded drainage 

channels. A series of ridges occur in the southern portion of the EIS analysis area, and these 

ridges obscure the site from I-80. Localized steep topography, including eroded cliff faces, exists 

in several places along the shoreline of the North Platte River and Seminoe Reservoir, which 

bisect the EIS analysis area. 

The EIS analysis area landscape is vegetated with grasses and shrubs, with only a few scattered 

cottonwood trees present along the banks of the North Platte River. The dominant colors in the 

area range from light to moderate greens in the springtime and early summer, to yellows and 

browns in the summer and the fall with sagebrush being grey-green year-around. The Seminoe 

Reservoir interrupts the existing landscape with a dominant bluish coloring; however, with recent 

drought conditions and low water levels, the shoreline of the reservoir presents a stark edging of 

light brownish coloration. 

Five key observation points (KOP) were established within and adjacent to the EIS analysis area 

to establish the general visual conditions. They do not include every possible viewpoint within the 

EIS analysis area. However, they provide representative views of the area and several are located 

at high points along CR 351 where drivers can see a vast expanse of the EIS analysis area. The 

locations of these KOPs are shown on Figure 48, Visual Resource Management, and the 

photographs taken from these sites are shown as: 

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November 2005 Draft Environmental Impact Statement

� Figure 49, Key Observation Point #1, 

� Figure 50, Key Observation Point #2, 

� Figure 51, Key Observation Point #3, 

� Figure 52, Key Observation Point #4, and 

� Figure 53, Key Observation Point #5. 

Two important factors considered in selecting the KOPs were 1) points where the most viewers 

would see the project and 2) the length of time they would see the project. Most viewers would 

see the project from Seminoe Road, where they would view portions of the project for 

approximately 9 miles. In addition, as stated in Section 3.11, Recreation, the Seminoe Road has 

been designated as a “National Back Country Byway” by the BLM. 

3.13.1 Visual Resource Management Classes

BLM uses VRM classes to represent the degree of acceptable visual change within a 

characteristic landscape. A class is based on the physical and sociological characteristics of any 

given homogenous area and serves as a management objective. The objectives for the four 

classes as described in the BLM VRM manual 8432 are described below: 

Class I Objective. The objective of this class is to preserve the existing character of the 

landscape. This class provides for natural ecological changes; however, it does not preclude very 

limited management activity. The level of change to the characteristic landscape should be very 

low and must not attract attention. There are no Class I VRM areas in the EIS analysis area. 

Class II Objective. The objective to this class is to retain the existing character of the landscape. 

The level of change to the characteristic landscape should be low. Management activities may be 

seen, but should not attract the attention of the casual observer. Any changes must repeat the 

basic elements of form, line, color, and texture found in the predominant natural features of the 

characteristic landscape. Approximately 55% of the EIS analysis area is designated as Class II 

VRM area. See Figure 48, Visual Resource Management. 

Class III Objective. The objective of this class is to partially retain the existing character of the 

landscape. The level of change to the characteristic landscape should be moderate. Management 

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activities may attract attention but should not dominate the view of the casual observer. Changes 

should repeat the basic elements found in the predominant natural features of the characteristic 

landscape. Approximately 45% of the EIS analysis area is designated as Class III VRM area. See 

Figure 48, Visual Resource Management. 

Class IV Objectives. The objective of this class is to provide for management activities, which 

require major modification of the existing character of the landscape. The level of change to the 

characteristic landscape can be high. These management activities may dominate the view and 

be the major focus of viewer attention. However, every attempt should be made to minimize the 

impact of these activities through careful location, minimal disturbance, and repeating the basic 

elements. There are no Class IV VRM areas in the EIS analysis area. 

Under the existing Great Divide RMP dated November 1990, the EIS analysis area contains both 

Class II and Class III areas (BLM 1990). See Figure 48, Visual Resource Management. 

Approximately 55% of the EIS analysis area is Class II, while 45% is Class III. 

3.14 Socioeconomics

The EIS analysis area is located in Carbon County, which covers nearly 8,000 square miles, 

making this county the third largest in size in Wyoming. This section provides an overview of the 

existing socioeconomic conditions of Carbon County, with particular focus on the city of Rawlins 

where such data is available. Other cities included in this overview are Hanna and Sinclair; 

information about these two Carbon County towns is included where data are available and 

pertinent. 

3.14.1 Population

As of 2000, Carbon County had an estimated population of 15,639 persons, which was 

approximately 3.2% of the 2000 Wyoming population. The town of Rawlins, the county seat of 

Carbon County, had a population of 9,006 persons. Census populations for 1970 through 2000 for 

Wyoming, Carbon County, Rawlins and other nearby towns are set forth in Table 3.14-1, Historic 

Populations. 

Carbon County and the towns of Rawlins, Hanna and Sinclair have experienced declining 

population since the 1980 census. This is primarily the result of a declining economic environment 

over the past two decades caused by decreased coal and oil and gas production in the county. 

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Table 3.14-1, Historic Populations 

Place 1970 1980 % Change 

1970-80 1990 % Change 

1980-90 2000 % Change 1990-2000 

Wyoming 332,416 469,557 41% 453,589 (3%) 493,782 9% 

Carbon 

County 

13,354 21,896 64% 16,659 (24%) 15,639 (6%) 

Rawlins 7,855 11,547 47% 9,380 (19%) 9,006 (4%) 

Hanna 460 2,288 397% 1,076 (53%) 873 (19%) 

Sinclair 445 586 32% 500 (15%) 423 (15%) 

Source: U.S. Department of Commerce, Bureau of the Census 

( ) denotes negative decline 

Although Wyoming expects moderate population growth into the future, population in Carbon 

County is predicted to continue to decline. See Table 3.14-2, Population Trends. 

Table 3.14-2, Population Trends 

Place 2000 2003 2005 2010 % Change 2000-10 2020 % Change 2010-20 

Wyoming 493,782 501,242 506,184 519,595 5% 533,534 3% 

Carbon 

County 

15,639 15,302 15,047 14,671 (6%) 13,965 (5%) 

Rawlins 9,006 8,665 8,539 8,325 (8%) 7,925 (5%) 

Hanna 873 874 855 834 (4%) 793 (5%) 

Sinclair 423 408 404 394 (7%) 375 (5%) 

Sources: 

1. U.S. Department of Commerce, Bureau of the Census for year 2000 

2. Wyoming Department of Administration and Information, Economic Analysis Division for 2003, 2005, 2010 

and 2020 population estimates and forecasts 

( ) denotes negative decline 

3.14.2 Housing

The 2000 census provides housing data for Wyoming, Carbon County and towns with the county. 

See Table 3.14-3, Housing Profile: 2000. 

Table 3.14-3, Housing Profile: 2000 

Housing Units 

Wyoming Carbon County Rawlins Hanna Sinclair 

Number % Number % Number % Number % Number % 

Owner-occupied 135,514 61 4,354 52 2,247 58 273 53 146 69 

Renter-occupied 58,094 26 1,775 21 1,073 28 94 18 22 11 

Sub-total 

Occupied 193,608 87 6,129 73 3,320 86 367 71 168 80 

Vacant: For Sale 

or Rent 17,857 8 1,128 14 490 13 132 26 40 19 

Seasonal Vacant 12,389 5 1,050 13 50 1 15 3 3 1 

Sub-total Vacant 30,246 13 2,178 27 540 14 147 29 43 20 

Total 223,854 100 8,307 100 3,860 100 514 100 211 100 

Source: Wyoming Department of Administration and Information, Economic Analysis Division 

In 2000, vacant housing units for sale or rent in Carbon County were 6% higher than the average 

Wyoming statewide rate. In 2000, the town of Hanna had vacant housing rates 18% higher than 

the Wyoming average. 

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Owner-occupied housing units in Carbon County were lower in 2000 than the Wyoming statewide 

average, except in the town of Sinclair, where there were 8% more owner-occupied housing units 

than the Wyoming statewide average. 

In 2000, Carbon County reported an 8% higher seasonal vacancy rate than the Wyoming 

statewide average. Hanna had a 10% higher rate. These elevated figures represent that certain 

individuals are maintaining houses until the economy rebounds with new jobs or housing prices 

increase to a level where the houses can be sold. In addition, there may be vacation houses or 

trailers located in places like the “Boat Club” at Seminoe Reservoir, or communities such as 

Saratoga and Encampment. 

Household size for owner and renter occupied units are set forth in Table 3.14-4, Average 

Household Size: 2000. Households throughout Wyoming and in Carbon County tend to average 

between two to three persons. 

Table 3.14-4, Average Household Size: 2000 

Subject Wyoming Carbon County Rawlins Hanna Sinclair 

Average household size of owner-occupied 

units 2.58 2.46 2.58 2.36 2.49 

Average household size of renter-occupied 

units 2.25 2.24 2.16 2.43 2.73 

Source: Wyoming Department of Administration and Information, Economic Analysis Division 

Housing values in Carbon County are typically lower than in the rest of Wyoming. See Table 3.14­

5, Housing Values and Costs: 2000. The median value for a home in Carbon County in 2000 

was $76,500 as compared to $96,600 in Wyoming. Hanna had the lowest reported 2000 median 

housing value in Carbon County at $45,500. Further, for the year 2000, there were no housing 

values in the towns of Rawlins, Hanna and Sinclair that exceeded values of $300,000, whereas 

nearly 4% of the houses in Wyoming exceeded that amount. 

In 2000, more than 65% of Wyoming homeowners made monthly mortgage payments that 

averaged $825. In Carbon County, slightly less homeowners (59.2%) than the statewide average 

made monthly mortgage payments averaging between $515 (Hanna) and $681 (Rawlins). See 

Table 3.14-5, Housing Values and Costs: 2000. 

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Table 3.14-5, Housing Values and Costs: 2000 

Subject Wyoming Carbon County Rawlins Hanna Sinclair 

HOUSING VALUE (%) 

Less than $50,000 8.3% 20.1 18.1 60.7 31.3 

$50,000 to $99,999 45.3% 55.7 60.7 36.9 62.7 

$100,000 to $149,999 27.2% 15.6 15.0 -- 6.0 

$150,000 to $199,999 10.0% 5.1 4.0 2.4 --

$200,000 to $299,999 5.6% 2.6 2.2 -- --

$300,000 to $399,999 2.0 0.4 -- -- --

$500,000 to $999,999 0.9 0.3 -- -- --

More than $1,000,000 0.6 0.3 -- -- --

Median Value (dollars) $96,600 $76,500 $73,700 $45,500 $68,800 

MORTGAGE DATA (%) 

With a mortgage 65.7 59.2 63.9 60.7 58.2 

Less than $300 0.6 0.7 0.8 -- --

$300 to $499 6.1 9.0 8.4 28.2 16.4 

$500 to $699 15.6 21.8 25.6 24.3 18.7 

$700 to $999 23.0 20.0 22.1 8.3 18.7 

$1,000 to $1,499 14.9 6.8 6.5 -- 4.5 

$1,500 to $1,999 3.7 0.5 0.5 -- --

More than $2,000 1.9 0.5 -- -- --

Not mortgaged 34.3 40.8 36.1 39.3 41.8 

Median Monthly Mortgage (dollars) $825 $685 $681 $515 $638 

GROSS RENT DATA 

Less than $200 6.4 9.5 12.5 5.0 --

$200 to $299 10.0 13.9 13.9 22.0 16.1 

$300 to $499 42.0 43.3 46.8 50.0 67.7 

$500 to $749 23.6 14.8 15.7 6.0 16.1 

$750 to $999 5.5 1.5 1.8 5.0 --

$1,000 to $1,499 2.0 0.5 0.6 -- --

More than $1,500 0.7 0.4 0.6 -- --

No cash rent 9.8 16.0 8.1. 12.0 --

Median Monthly Gross Rent (dollars) $437 $377 $369 $390 $363 

Source: Wyoming Department of Administration and Information Economic Analysis Division 

Monthly rent in 2000 averaged $437 in Wyoming (statewide) as compared to an average Carbon 

County monthly rent of $377. Monthly rental payments averaged slightly higher in Hanna ($390), 

while monthly average rental payments were lower in Rawlins ($365) and Sinclair ($363). See 

Table 3.14-5, Housing Values and Costs: 2000. 

3.14.3 Demographic Characteristics

According to the 2000 Wyoming Census, Wyoming and the town of Rawlins had nearly similar 

median ages of 36 years, although the median age of residents in Hanna and Sinclair was older, 

averaging over 41 years. In Wyoming and Carbon County, on average, there were more males 

than females; however, the town of Sinclair had slightly more females than males. See Table 

3.14-6, General Demographic Characteristics: 2000. 

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Table 3.14-6, General Demographic Characteristics: 2000 

Subject Wyoming Carbon County Rawlins Hanna Sinclair 

Sex 

Male (%) 50.3 53.6 52.7 51.4 49.4 

Female (%) 49.7 46.4 47.3 48.6 50.6 

Age 

Under 5 years (%) 6.3 5.7 6.8 4.9 3.5 

5 to 9 years (%) 6.9 6.1 6.7 7.9 6.9 

10 to 14 years (%) 7.8 7.1 7.2 7.6 10.2 

15 to 19 years (%) 8.5 7.9 8.4 6.8 9.7 

20 to 24 years (%) 6.8 5.9 7.1 4.5 3.1 

25 to 34 years (%) 12.1 11.4 12.3 9.5 8.0 

35 to 44 years (%) 16.0 16.9 17.1 14.1 18.0 

45 to 54 years (%) 15.0 16.5 15.3 17.4 19.6 

55 to 59 years (%) 5.0 5.8 5.3 7.6 4.3 

60 to 64 years (%) 4.0 4.4 3.6 5.2 4.0 

65 to 74 years (%) 6.3 6.8 5.6 10.1 4.5 

75 to 84 years (%) 4.0 4.0 3.7 4.4 5.2 

85 years and over (%) 1.4 1.4 1.0 0.2 3.1 

Median Age (years) 36.2 38.9 36.1 41.6 41.4 

Racial/Ethnic Minorities 

Black/African American (%) 0.8 0.7 0.8 0.2 0.5 

American Indian (%) 2.3 1.3 1.5 -- 1.4 

Hispanic or Latino (%) 6.4 13.8 21.0 5.5 2.6 

Asian (%) 0.6 0.7 0.8 0.1 --

Other (%) 4.4 7.4 11.0 4.1 1.8 

In addition, according to the 2000 U.S. Census, an estimated 14.5% of Wyoming residents and 

23.9% of Carbon County residents represented racial and ethnic minorities. In Rawlins, an 

estimated 35.1% of the town’s residents represented racial and ethnic minorities. Hispanic or 

Latino residents represented the largest minority/ethnic group, accounting for 6.4% of Wyoming’s 

population, 13.8% of Carbon County population, and 21.0% of Rawlins residents. See Table 3.14­

6, General Demographic Characteristics: 2000. 

According to 2000 data from the U.S. Bureau of Census, nearly 90% of Wyoming’s population (25 

years and older) had earned a high school degree or higher. This ranked Wyoming third in all 50 

states. Approximately 20% of Wyoming residents (25 years and over) have a Bachelor’s degree 

or higher. 

Educational information is set forth in Table 3.14-7, Educational Attainment: 2000. These 

statistics show that over 80% of residents in both Carbon County and throughout Wyoming have 

earned high school degrees; however, on a percentage basis, less people in Carbon County have 

received high school degrees than in Wyoming statewide. Similarly, the population 25 years and 

older receiving a Bachelor’s degree or higher is slightly lower in Carbon County (17.2%) than in 

Wyoming (21.9%), with the lowest readings being Hanna (13.4%) and Sinclair (13.5%). 

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Table 3.14-7, Educational Attainment: 2000 

Subject Wyoming Carbon County Rawlins Hanna Sinclair 

Percent High School Graduate or Higher 87.9 83.5 81.7 85.3 86.5 

Percent Bachelor’s Degree or Higher 21.9 17.2 15.0 13.4 13.5 

Population 25 Years and Over 

Total 315,663 10,508 5,522 552 281 

Percentage 100.0 100.0 100.0 100.0 100.0 

Less Than 9th Grade 

Total 10,614 541 344 18 7 

Percentage 3.4 5.1 6.2 3.3 2.5 

9th to 12th Grade No Diploma 

Total 27,703 1,192 664 63 31 

Percentage 8.8 11.3 12.0 11.4 11.0 

High School Graduate (includes equivalency) 

Total 97,779 3,678 1,971 239 92 

Percentage 31.0 35.0 35.7 43.3 32.7 

Some College – No Degree 

Total 85,184 2,685 1,391 132 86 

Percentage 27.0 25.6 25.2 23.9 30.6 

Associate Degree 

Total 25,221 609 323 26 27 

Percentage 8.0 5.8 5.8 4.7 9.6 

Bachelor’s Degree 

Total 47,066 1,254 559 55 31 

Percentage 14.9 11.9 10.1 10.0 11.0 

Graduate or Professional Degree 

Total 22,096 549 270 19 7 

Percentage 7.0 5.2 4.9 34 2.5 

Source: Wyoming Department of Administration and Information, Economic Analysis Division 

3.14.4 Employment and Economic Conditions

Total employment in Carbon County decreased from 7,820 persons in 1992 to 7,672 in 2002. 

During that same period, the Carbon County unemployment rate also dropped from 6% to 4.6%. 

In 1992, the labor force in Carbon County was 8,318 persons; in 2002, the labor force had 

declined to 8,038. These figures reveal that persons have left Carbon County and left the labor 

force. 

The services and professional segment accounts for the largest segment of the Carbon County 

economy, consistently being above the 50% level. The second largest job segment in Carbon 

County is employment with federal, state and local government. The government segment of the 

local employment economy remained fairly consistent between 1970 and 2000, averaging around 

20%. See Figure 55, Carbon County Jobs - 1970 and 2000. 

Carbon County employment between 1970 and 2000 is graphically shown on Figure 54, Carbon 

County Employment by Industry (1970-2000). Coal mining employment peaked in Carbon 

County in 1981 with over 3,500 jobs. The Carbon County coal mining industry has yet to recover 

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to those early 1980s levels. Even if coal mine production (tonnage) returns to its former peak 

levels, the mining employment would not replicate the peak job levels of the early 80s. Over the 

past two decades, the U.S. coal mining industry has undergone a period of economic restructuring 

and resulting productivity gains. Coal tonnage being produced in America today is accomplished 

with much lower employment levels. 

The composition for employment in Wyoming and Carbon County showed that in 2000 

approximately 60% of those who were 16 years and older were in the labor force. See Table 3.14­

8, Employment Status: 2000. In the town of Sinclair, 73.1% of those 16 years and older were in 

the labor force; while in Hanna, only 54.4% of those 16 years and older were in the labor force. 

Table 3.14-8, Employment Status: 2000 

Subject Wyoming Carbon County Rawlins Hanna Sinclair 

Population 16 Years and Over 

Total 381,912 12,392 6,725 656 320 

Percentage 100.0 100.0 100.0 100.0 100.0 

Employed Civilian Labor Force 

Total 241,055 7,335 4,087 357 234 

Percentage 63.1 59.2 60.8 54.4 73.1 

Armed Forces 

Total 3,300 -- -- -- --

Percentage 0.9 -- -- -- --

Unemployed 

Total 13,453 409 233 40 12 

Percentage 3.5 3.3 3.5 6.1 3.8 

Not in Labor Force 

Total 124,104 4,648 2,405 259 74 

Percentage 32.5 37.5 35.8 39.5 23.1 

Source: Wyoming Department of Administration and Information, Economic Analysis Division 

In 2002, the unemployment rate in Carbon County was 4.6%, slightly higher than the Wyoming 

statewide unemployment rate of 4.2%. In 2002, the unemployment rate for the entire United 

States was 5.8%. 

With the exception of a period from 1997 to 2000, Wyoming unemployment rates have 

consistently been below U.S. unemployment rates since 1990. See Figure 57, Unemployment 

Rates. 

3.14.5 Income

In 2000, personal income per capita in Carbon County averaged $23,671, 17% below the $28,463 

per person income for Wyoming and 21% below the $29,847 per capita income for the U.S. 

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Personal income is the amount of income an individual receives annually before taxes. It includes 

wages, salaries, proprietors’ income, other labor income, investment income and transfer 

payments. Between 1990 and 2000, personal income per capita in Carbon County increased by 

from $17,234 to $23,671, a 27% increase. 

Between 1970 and 2000 total personal income in Carbon County remained relatively stagnant, 

with the exception of a period between the mid 70s and mid 80s, when mining income peaked 

(1981) then dramatically dropped (1987). See Figure 56, Carbon County Personal Income 

(1970-2000). 

In 2000, the average wage per worker in Carbon County was $24,825 compared to $26,602 in 

Wyoming and $36,167 for the U.S. highest-paid wages in Carbon County were in the mining 

sector (which includes oil and gas workers) where the average worker earned $45,781, almost 

twice the county and statewide wage average. 

Reported income data alone does not necessarily provide a complete picture of economic activity 

in an area. Residents of rural areas may accept lower incomes than residents of metropolitan 

areas to obtain amenities such as rural life styles, low crime rates and recreational opportunities. 

3.14.6 Community and Public Services

During the EIS process, area community and public service providers were contacted to obtain 

information regarding current services. This assessment focused on the following providers: 

� Education 

� Law Enforcement 

� Fire Protection 

� Ambulance 

� Hospital and Medical Services 

� Social Services 

� Water Supply 

� Wastewater Treatment 

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� Solid Waste 

� Electric Utilities 

3.14.6.1 Education

Public schools in Rawlins, Hanna and Sinclair are included in Carbon County School District #1. 

This school district includes four elementary schools with grades K-5, one middle school located 

in Rawlins, one middle school located in Bairoil and two high schools. School enrollment has 

decreased over the past 5 years. The total 1999 enrollment equaled 1,951 students, while total 

enrollment in 2003 dropped to 1,708 students, a decrease of 12%. 

Student enrollment and occupancy rates for District #1 high schools are set forth in Table 3.14-9, 

School Enrollment. Most District #1 schools have occupancy rates between 60 and 80%. 

Table 3.14-9, School Enrollment 

School Grades 

Design 

Occupancy 

Current 

Occupancy 

Student Teacher 

Ratio 

Highland Hills K-5 361 75% 17.5:1 

Mountain View K-5 209 112% 16.4:1 

Pershing K-5 247 70% 15.7:1 

Sinclair K-5 76 51% 10.9:1 

Bairoil K-5 95 80% 6:1 

Rawlins Middle School 6-8 735 78% 17.1:1 

Rawlins High School 9-12 882 78% 17.8:1 

Cooperative High School 9-12 168 66% 22.5:1 

Source: Sanders, Carbon County District 1, 2004 

There are currently no plans for new schools or expansions of existing schools, or school staffing 

increases (Sanders, personal communication 2004). 

Carbon County School District #1 currently employs a total of 284 administrative, teacher and 

support staff. The teacher/class ratios for the various District #1 schools are set forth in Table 

3.14-9, School Enrollment. 

3.14.6.2 Law Enforcement

The Carbon County Sheriff’s and Rawlins’s Police Department staffs provide law enforcement 

services in the area. These two groups cooperate on law enforcement in and around the town of 

Rawlins. The Carbon County Sheriff’s Department provides law enforcement services for the 

communities of Hanna and Sinclair. 

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The Rawlins Police Department consists of twenty-one sworn officers, eight dispatchers, and one 

victim’s advocate. There are twenty-one police vehicles assigned to the Rawlins police force. The 

Rawlins Police Department currently considers themselves slightly under staffed (Chapman, 

personal communication 2004). 

The Carbon County Sheriffs Department employs a sheriff, an under sheriff, seven deputies and 

two full time dispatchers. There are nine vehicles for this department. Currently, the Sheriff’s 

Department considers itself adequately staffed for the needs of the county. 

The Wyoming State Patrol patrols I-80 through Carbon County on a daily basis. In addition to 

providing law enforcement for the Wyoming interstate and state highway system, the state police 

also provide assistance to the Carbon County Sheriff’s Department and the Rawlins Police 

Department on an as-needed basis. 

In addition, the Wyoming Department of Game & Fish (WDGF) employs wildlife enforcement 

officers who are responsible for enforcing fish and game regulations in Carbon County. 

3.14.6.3 Fire Protection

Fire protection is provided for Carbon County by a countywide fire protection district. The fire 

protection district includes eleven fire stations, two of which are located in the town of Rawlins. 

Fire stations are equipped with at least three pieces of fire protection equipment, with eight pieces 

of equipment permanently located in Rawlins. Fire protection personnel are volunteers. There are 

a total of 120 volunteer firefighters countywide, with 30 located in the town of Rawlins. Firefighting 

volunteers are trained for fire control and first aid. The Fire Protection District Manager believes 

that the district is adequately staffed (France, Carbon County Fire Warden, personal 

communication 2004). 

The BLM provides fire protection coverage for their holdings, and seasonal fire crews and 

personnel are stationed in Rawlins. The BLM coordinates with local fire districts for initial 

response, mutual aid and cooperative fire control. 

3.14.6.4 Ambulance

Ambulance service is owned and operated by the Rawlins Hospital. The medical director of the 

ambulance service also serves as the medical director for the Hanna, Wamsutter, and Bairoil 

ambulance services. This ambulance service provides ground transportation to the Rawlins 

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Hospital. Air ambulance service is available for Carbon County from hospitals located in Laramie 

and Cheyenne. 

3.14.6.5 Hospital and Medical Services

The Memorial Hospital of Carbon County provides medical care and services for the county. The 

hospital is licensed as a home health agency and community-based in-home service for Carbon 

County. The hospital also operates as a pediatric clinic, orthopedic clinic and a medical clinic in 

Hanna. The hospital maintains thirty-five acute care beds, including medical, surgical, pediatric 

unit, five intensive care unit beds, three bed and five bassinette obstetric unit, two operating 

rooms and ambulatory surgical unit and an emergency room. 

On average, per month, there are 700 to 800 emergency room visits; eight to ten babies 

delivered; and 70 to 90 surgeries performed. 

The hospital employs 200 people. The staff includes four physicians on active medical time, three 

family practioners, two family practitioners that also do OB, five emergency room physicians, one 

general vascular surgeon, one orthopedic surgeon, one radiologist and one pediatrician. In 

addition, there are sixteen physicians on courtesy medical staff that come to Rawlins to conduct 

clinics one to two times per month. There are no plans to expand hospital or medical services 

since they currently meet Carbon County demands (Carter, personal communication 2004). 

3.14.6.6 Social Services

Carbon County Social Services provides public assistance to low-income families and the elderly. 

Overall, caseloads are decreasing, except for assistance to the elderly, which has been 

increasing. Carbon County non-profit organizations, such as churches, also provide a variety of 

social service programs. 

3.14.6.7 Water Supply

The town of Rawlins maintains a new water treatment facility with a 7 million gallon per day 

capability. Current water use in Rawlins is less than 5 million gallons per day. 

3.14.6.8 Wastewater Treatment

A Rawlins wastewater treatment facility serves the towns of Rawlins and Sinclair. This wastewater 

treatment plant is designed for twice the current population or roughly 20,000 homes. Since 1999, 

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over $9 million has been invested in improvements on the Rawlins wastewater treatment plant. 

3.14.6.9 Solid Waste

A solid waste landfill near Rawlins serves the communities of Rawlins and Sinclair and solid waste 

pick-up service in these towns is provided by privately-licensed local contractors. The landfill is 

owned by the town of Rawlins and has a projected life of eight more years. The state of Wyoming 

is currently assessing the possibility of enlarging the facility to serve the entire county, but, at 

present, plans are not finalized and no decisions to expand the existing landfill have been made. 

3.14.6.10 Electric Utilities

Electrical power for Rawlins and vicinity is provided by Pacific Power and Light Company, which 

has adequate capabilities to serve customers. Carbon Power and Light Company serves 

customers in Saratoga and vicinity. 

3.14.7 Fiscal Conditions

Oil, gas and coal mining operations generate a significant amount of federal, state and local 

government revenues. The federal government receives revenue for land and mineral right 

leases, as well as royalties. The state of Wyoming receives tax revenues primarily from federal 

royalties, sales, severance, and property taxes. There are no personal or corporate income taxes 

in Wyoming. Local governmental entities receive property, sales and severance taxes, as well as 

a share of federal royalties and PILT (payment in lieu of taxes) from the federal government. 

Additional governmental revenues are generated from businesses that supply oil and gas 

operations with goods and services, as well as from employees of oil and gas exploration, 

development and production. Local purchases made by oil and gas operations generate sales 

taxes. 

Oil and gas workers are also a source of government revenues. Income earned by oil and gas 

workers are subject to federal income taxes. Household purchases generate sales taxes, and the 

property owned by oil and gas workers is subject to property taxes. 

3.14.7.1 State of Wyoming Revenues

Net state revenue collections totaled over $1.2 billion in 2003, up nearly 10% from 2002 when just 

under $1.1 billion was collected. Wyoming revenue collections have been increasing steadily over 

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the past 5 years. See Figure 58, Wyoming State General Revenues (1992-2002) and Figure 

59, Wyoming General Revenue Source. 

Over 42% of Wyoming revenue collections are from sales and gross receipts. Severance tax, 

collected from oil, gas and mining operators, accounts for over 36% of Wyoming revenues, and 

this revenue is redistributed back to local jurisdictions. The various sources of tax collections for 

Wyoming are shown on Figure 60, Wyoming State Tax Revenue Collections 2002 and 2003. 

The state of Wyoming also receives “intergovernmental” revenue; this revenue is distributed by 

the federal government. In 2002, intergovernmental received by Wyoming was approximately $1.2 

billion, or slightly more than the $1.1 billion collected within the state of Wyoming. 

The state of Wyoming distributes approximately 33% of its total revenues back to county and local 

government entities. On a statewide expenditure basis (i.e., direct expenditures), the state of 

Wyoming expends nearly 30% of its direct expenditures on education, nearly 13% on public 

welfare, and 12% for highways. See Figure 61, Wyoming State Expenditures - 2002. 

3.14.7.2 Retail Sales and Use Taxes

Wyoming has a statewide 4% sales and use tax. Carbon County collects an additional 2% in sales 

taxes: 1% as a general purpose county option tax and another 1% as a specific-purpose county 

option tax. For fiscal year 2001, Carbon County collected a total of $19.8 million in sales and use 

taxes; this was down approximately 5% from fiscal year 2000, when Carbon County collected 

about $21 million in sales and use tax. 

An estimated 28% (less administrative costs) of statewide sales and use tax collections and all of 

the local sales and use tax collections (also less administrative costs) are distributed to Carbon 

County and its incorporated municipalities according to a population-based formula. 

3.14.7.3 Property Tax

Wyoming’s total assessed valuation for the 2001 tax year was $10.5 billion, up 33.5% from the 

2000 tax year, when assessed valuation was $7.9 billion. Property tax levies increased a 

corresponding 31.5%, up $167 million from $529 million in 2000 and $696 million in 2001. 

Wyoming treats mineral production as personal prop100100100y for Ad Volorem tax purposes; 

prior year calendar production is included in the state’s current-year tax base. The 2001 taxable 

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value of 2000 production was $6.4 billion, 57% higher than the 2000 taxable value of 1999 

production, which was $4.1 billion. 

Wyoming residential property increased in value by 12.2%, from $1.8 billion (2000) to nearly $2 

billion (2001). Industrial property increased from a 2000 assessed value of $1.36 billion to $1.41 

billion in 2001, a 3.9% increase. Commercial property also increased 8.7%, from $534 million 

(2000) to $580 million (2001). The value of agricultural lands decreased 2.2% from 2000 to 2001, 

from $146 million to $142 million. 

Mineral production is assessed at 100% of value, industrial property at 11.5% and all other 

property at 9.5% of market value. Agricultural land is assessed at 9.5% of productivity value. 

Carbon County experienced a 64% increase in property tax revenues, going from $21.3 million in 

2000 to $34.9 million in 2001. The primary reason for this increase in property tax revenues was 

the increase in oil and gas activity. 

3.14.7.4 Severance Tax

Wyoming collects a 6% severance tax on oil and gas. Revenues from severance taxes are 

distributed to the Wyoming Mineral Trust Fund, General Fund, Water Development Fund, 

Highway Fund, Budget Reserve Account, and to counties and incorporated cities and towns. In 

2003, severance tax collections totaled $441 million, up nearly 32% from the $302 million 

collected in 2002. 

Since 1995, the trend in severance taxes paid in Wyoming generally has been up, but with 

significant annual variations. See Figure 62, Wyoming Severance Tax Trends (1992-2003). 

3.14.7.5 Federal Royalties

The federal government collects a 12.5% royalty on oil, natural gas and surface-mined coal 

extracted from federal lands. For underground coal mining on federal land, there is an 8% royalty. 

Fifty percent of federal royalties are retained in the federal treasury, while the other 50% is 

returned to the state where production occurred to help address impacts from mineral 

development on federal lands. 

In Wyoming, the state’s share of federal mineral royalties is distributed to a variety of accounts as 

follows: 

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� 50% to the county where production occurred, 

� 25% to the State School Fund, 

� 15% to the Highway Fund, and 

� 10% to the General Fund. 

Wyoming also receives federal funds under the Payment In Lieu of Taxes Act, which 

compensates county governments whose jurisdictions contain tax-exempt federal lands. For fiscal 

year 2004, Wyoming will receive $14.6 million, of which Carbon County will receive $654,838. 

3.14.8 Social Values

The communities of Rawlins, Hanna and Sinclair have a long history with transportation, 

agriculture, mining and construction. Most households in these communities identify with “making 

a living from the land,” and these communities continue to obtain economic benefits from the 

relatively high-wage jobs associated with oil and gas exploration and development. Most residents 

in these communities tend to value economic opportunity as represented by natural resource 

activities (agriculture, mining, construction, oil and gas exploration and development) but some 

also raise concerns about the impacts of such activity on land use and recreation. 

As explained in Section 3.14.1, Population, Carbon County has experienced a decrease in 

population and employment over the past several decades. Unlike other communities in the west, 

the towns of Rawlins, Hanna and Sinclair have not experienced a migration of newer residents 

that are less supportive of traditional natural resource activities. Most residents of the region still 

view mining and oil and gas activities as having a positive effect on the quality of life because of 

economic stimulus and job opportunities. 

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Chapter 4 ­ Environmental Consequences

This EIS chapter examines the anticipated environmental effects associated with the 

implementation of the action alternatives in comparison to the no action alternative. The 

environmental analysis for the action alternatives presented in Chapter 4 represents mitigated 

effects, based on mitigation and reclamation measures discussed in Chapter 2. 

For ease of presentation and comparison, the impact analysis discussions in Chapter 4 are 

grouped by the same technical disciplines as addressed in Chapter 3. This chapter’s analyses 

emphasize those effects related to key issues and concerns identified in Chapter 1. Some effects 

are expressed in qualitative terms, others in quantitative terms. 

Impact descriptions under each resource area are divided into the following categories: 

� Effects of the no action alternative; 

� Effects common to all action alternatives; and, 

� Effects unique to each action alternative. 

Impacts are evaluated for the alternatives and are defined as follows. 

� Direct Impacts – Those effects, which occur at the same time and in the same general 

location as the activity causing the effects. 

� Indirect Impacts – Those effects which occur at a different time or different location than 

the activity to which the effects are related. 

� Cumulative Impacts – Those effects which result from the incremental impact of the 

action when added to other past, present and reasonably foreseeable actions. 

4.1 Air Quality/Climate

Air Quality/Climate Impact Significance Criteria: Potential impacts considered significant if: 

� Potential total near-field concentrations are greater than WAAQS and NAAQS; 

� Potential total far-field concentrations are greater than WAAQS and NAAQS; 

Seminoe Road Gas Development Project 4­1
Draft Environmental Impact Statement November 2005

� Potential cumulative near-field concentrations are greater than PSD Class II increments; 

� Potential cumulative far-field concentrations in parks and Wilderness Areas in the region 

are greater than PSD Class I increments; 

� Potential decrease in visibility in parks and Wilderness Areas in the regions are greater 

than FLAG. Potential visibility impacts as compared to established Forest Service and 

Park Service thresholds (See Appendix H, Air Quality Information); 

� Potential decrease in ANC in sensitive lakes in the region are greater than levels of 

acceptable change; 

� Potential total deposition from the proposed project as compared to deposition analysis 

thresholds (See Appendix H, Air Quality Information). 

Fugitive dust and gaseous emissions would occur during the construction, production, and final 

reclamation phases of all action alternatives. However, no adverse direct, indirect or cumulative 

impacts to air quality from the project alone are0 anticipated. Further, no long-term air quality 

impacts would occur from the project because disturbed areas would be stabilized and reclaimed 

upon project closure. 

A comprehensive air quality analysis was conducted to assess potential direct and indirect nearfield criteria air pollutant impacts, hazardous air pollutant (HAP) impacts, and far-field (cumulative) 

impacts on ambient air pollutant concentrations, visibility, and atmospheric deposition (acid rain) 

that would most likely occur from the project (TRC 2004). Air quality specialists from the BLM, 

EPA, Wyoming DEQ Air Quality Division, U.S. Forest Service, and the National Park Service 

jointly participated in the development of a protocol that was applied to this analysis. A discussion 

of the modeling assumptions and protocol, along with an overview of the process that led to the 

completion of the Seminoe Road Project’s air quality analysis is set forth in Appendix H, Air 

Quality Information. 

The air quality impact analysis results presented in this EIS should be used to compare the 

relative impacts from various activities, alternatives and sources. Wyoming state law requires that 

the Wyoming DEQ, Air Quality Division ultimately determine whether this project would cause or 

contribute to any violation of ambient air quality standards and conforms to other regulatory 

requirements prior to approving an Air Quality Construction Permit. See Appendix D, Agency 

Jurisdictions (Permits and Approvals). The Wyoming DEQ, Air Quality Division would make 

4­2 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

the final determination in their permitting processes even though the results of the air quality 

analysis presented herein demonstrate compliance with these requirements. 

4.1.1 Effects of Alternative A (No Action)

The Pilot Project operations could continue under the no action alternative. The BLM has 

previously assessed Pilot Project air quality impacts in a 2001 EA (WY-030-EA00-288), and the 

Wyoming DEQ Air Quality Division has issued the appropriate construction permits for this 

project. Fugitive dust and gaseous emissions do occur from the Pilot Project, but these emissions 

are localized and minimal. There have been no violations of state or federal air quality regulations 

or standards as a result of the Pilot Project. 

Air quality of the EIS analysis and surrounding areas would remain under the influence of existing 

cumulative sources and land use trends. Current land use trends in south-central Wyoming would 

continue, including increased oil and gas exploration and development, continued coal mining, 

increased truck and other vehicular traffic on I-80 and other highways, and increased recreational 

use including hunting, camping, off-road vehicle (ORV) traffic, boating and fishing activity on 

Seminoe Reservoir, fishing on the Miracle Mile, and other dispersed and developed recreation. 

Increased emissions in this region could cause incremental and localized degradation of air 

quality over time, although this increase may not be measurable unless the density of 

development increases significantly. 

The EIS analysis and surrounding areas are currently classified as being in attainment with 

existing EPA AAQS for all pollutants. With current and anticipated land use trends, the area is 

expected to continue to be classified as being in attainment with existing standards. 

4.1.2 Effects Common to All Action Alternatives

Emission sources would include vehicular traffic, well pad and access road construction, drilling, 

and compressor facilities under all action alternatives. Air pollutant emissions from these sources 

and activities would include fugitive dust, oxides of nitrogen (NOX), carbon monoxide (CO), sulfur 

dioxide (SO2), volatile organic compounds (VOC), and federally listed HAP that may include 

benzene, toluene, ethylbenzene, and xylenes (collectively called BTEX), and formaldehyde (TRC 

2004). 

Seminoe Road Gas Development Project 4­3
Draft Environmental Impact Statement November 2005

4.1.2.1 Fugitive Dust Emissions

Fugitive dust emissions would occur during construction and drilling activities within the EIS 

analysis area. Airborne dust is classified as PM10 and PM2.5, which are particulate matter with an 

aerodynamic diameter of less than 10 and 2.5 microns, respectively. Particulate emissions would 

occur during construction of access roads, well pads, compressor sites, utilities and pipeline 

installations, traffic on unpaved roads, and from wind erosion in areas of soil disturbance and 

topsoil stockpiling. These fugitive emissions would continue from traffic associated with drilling 

activities, long-term gas production operations, and project decommissioning and final 

reclamation. 

Maximum localized particulate matter impacts would result from well pad and road construction 

activities. A most-likely modeling scenario consisting of a well pad and a 2-mile access road was 

evaluated to predict particulate impacts. The EPA dispersion model AERMOD was utilized to 

model this configuration along with meteorological data collected at the Rock Springs airport 

during 2003. Representative background concentrations summarized in Table 3.1-2, 

Representative Background Ambient Air Concentrations (presented in Chapter 3), are added 

to model results to yield predicted ambient concentrations. 

Fugitive dust emissions generated by activities within the EIS analysis area are not predicted to 

have any significant effects on air quality. No violation of applicable state and federal PM10 and 

PM2.5 standards is expected to occur. Near-field particulate matter modeling results are 

summarized in Table 4.1-1, Maximum Modeled PM10 and PM2.5 Impacts. 

Table 4.1-1, Maximum Modeled PM10 and PM2.5 Impacts 

Pollutant Averaging 

Time 

Direct 

Modeled 

(μg/m3) 

Background 

(μg/m3) 

Total 

Predicted 

(μg/m3) 

WAAQS 

(μg/m3) 

NAAQS 

(μg/m3) 

PM10 

24-hour 20.4 33 53.4 150 150 

Annual 3.5 16 19.5 50 50 

PM2.5 

24-hour 7.1 13 20.1 65 65 

Annual 1.0 5 6.0 15 15 

4.1.2.2 Gaseous Criteria Pollutant Emissions

Gaseous emissions would result from the construction equipment used to build access roads and 

well pads, as well as from drill rig engines. In addition, work crew, management and supply 

vehicles commuting to and from the work sites would emit gaseous constituents. 

4­4 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Compressor units and well “down-hole” pumps would be powered by electricity as a result of the 

Proponent’s plans to electrify the field; this would essentially eliminate gaseous emissions from 

these production components. Proposed build-out plans provide for a few wells to be drilled in 

outlying areas in advance of full development of particular drilling phases; these wells would 

require temporary powered engines to drive down-hole well pumps until electric utility lines are 

installed (buried) to reach those wells. Therefore, the electrified alternative assessment would 

include very minor gaseous emissions. 

Gaseous emissions for a field-wide gas powered compressor and down-hole well pump scenario 

were modeled for comparison with the electrified scenario. This scenario would obviously produce 

greater NO2 and CO ambient concentrations than the electrified proposed action alternative. 

Maximum model NO2 and CO impacts are discussed in Section 4.1.5, Effects of Alternative C 

(Pipeline to Reservoir). 

The majority of SO2 ambient concentrations for any of the action alternatives would occur from 

construction drilling emissions. The modeling scenario developed to predict these impacts 

included a drilling rig at a well pad. The AERMOD model was utilized, and maximum predicted 

concentrations are provided in Table 4.1-2, Maximum Modeled SO2 Impacts. 

Table 4.1-2, Maximum Modeled SO2 Impacts 

Pollutant Averaging 

Time 

Direct 

Modeled 

(μg/m3) 

Background 

(μg/m3) 

Total 

Predicted 

(μg/m3) 

WAAQS 

(μg/m3) 

NAAQS 

(μg/m3) 

3-hour 15.4 132 147.4 1,300 1,300 

SO10 24-hour 7.6 43 50.6 260 365 

Annual 2.8 9 11.8 60 80 

Ozone is a criteria pollutant that would not be directly emitted from project activities but is formed 

in the atmosphere as a result of photochemical reactions that involve ambient concentrations of 

NO2 and VOC. Compliance with ambient air quality standards cannot be determined with 

conventional dispersion models because of the complex photochemical reactions that form 

ozone. As such, a nomograph developed from the Reactive Plume Model (Scheffe 1988) was 

utilized to predict maximum ozone impacts. 

Maximum ozone concentrations would result during periods when NOX and VOC emissions are at 

their highest, which would occur during production activities. The scenario developed to evaluate 

ozone concentrations consisted of 26 gas-powered, down-hole well pumps and a compressor 

Seminoe Road Gas Development Project 4­5
3

Draft Environmental Impact Statement November 2005

station. This arrangement represents the maximum number of wells anticipated to operate outside 

of the electrified region, combined with emissions from a single compressor station. The ozone 1­

hour ambient impact predicted to occur from the NOX and VOC emissions estimated for this 

3 configuration was 21.0 μg/m , and an 8-hour average ozone impact was estimated to be 14.7 

μg/m . These impacts combined with background concentrations are compared to the Ozone 

AAQS in Table 4.1-3, Maximum Modeled O3 Impacts. 

Table 4.1-3, Maximum Modeled O3 Impacts 

Pollutant Averaging 

Time 

Direct 

Modeled 

(μg/m3) 

RPM 

Background 

(μg/m3) 

Total 

Predicted 

(μg/m3) 

WAAQS 

(μg/m3) 

NAAQS 

(μg/m3) 

Ozone 1-hour 21.0 62.6 83.6 235 235 

8-hourl 14.7 62.6 77.3 157 157 

4.1.2.3 Hazardous Air Pollutant Emissions

HAP can be subject to “Maximum Available Control Technology” (MACT) if they qualify as major 

or area sources. Major sources are defined as those sources having the potential to emit 10 tons 

per year of any individual HAP or 25 tons per year of any combination of HAP. All other sources of 

HAP are referred to as area sources. 

The only expected HAP for the Seminoe Road Project would be formaldehyde. Very low levels of 

formaldehyde would be emitted during the production phase of the project from gas-powered 

engines used to power certain individual down-hole well pumps; however, these emissions would 

not qualify as a major or area source, and therefore would not be subject to MACT standards. 

Formaldehyde emissions from the project would not have any adverse effects on regional air 

quality, nor cause any short-term or long-term human health issues. 

4.1.2.4 Visibility

Visibility impacts are predicted utilizing far-field models. This modeling is discussed in more detail 

in Section 4.1.3, Cumulative Impacts, particularly as it relates to individual project contribution to 

periods of cumulative visibility impairment. 

4.1.2.5 Indirect Impacts

Indirect air quality impacts associated with the Seminoe Road Project would be negligible and 

primarily associated with vehicular traffic of employees and their families that would move into the 

4­6 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

region. Such traffic would probably be focused in the town of Rawlins and would not be 

concentrated in the vicinity of the EIS analysis area. 

4.1.3 Cumulative Impacts

Given the relative remoteness of the Seminoe Road Project and the expected low project 

emissions, no cumulative air quality impacts are expected for the near-field that would cause 

effects on the human environment based on ambient air quality standards. 

The nearest industrial source to this project is the Sinclair Refinery that is located approximately 

15 miles southwest of the EIS analysis area. 

Cumulative impacts were analyzed because each site-specific increase in pollutant emissions, 

including those from the Seminoe Road Project, adds to cumulative air quality impacts within 

south-central Wyoming. Currently expanding oil and gas exploration and development activities 

continue to contribute to cumulative effects on regional air quality. 

Possible impacts to Class I and sensitive Class II areas were analyzed for the Seminoe Road 

Project using the CALMET/CALPUFF modeling system (TRC 2004). This modeling system is 

approved by the EPA for use in conducting far-field air quality analyses. As shown on Figure 20, 

Air Quality Modeling Domain, the modeling domain included the following Class I and sensitive 

Class II areas existing in southwestern Wyoming and portions of eastern Idaho, northeastern Utah 

and northern Colorado: 

Class I Areas Class II Areas 

Bridger Wilderness Area Popo Agie Wilderness Area 

Fitzpatrick Wilderness Area Wind River Roadless Area 

Mt. Zirkel Wilderness Area 

Rawah Wilderness Area 

Savage Run Wilderness Area (Federal Class II, Designated as Class I by Wyoming) 

Dinosaur National Monument (Federal Class II, Designated as Class I by Colorado) 

Predicted pollutant ambient concentrations at these sensitive areas were compared to applicable 

air quality standards and to the Class I and Class II ambient air increments, as well as to assess 

impacts to Air Quality Related Values (AQRV). The AQRV analyzed included visibility/regional 

Seminoe Road Gas Development Project 4­7
Draft Environmental Impact Statement November 2005

haze and atmospheric deposition. Potential lake acidification from atmospheric deposition impacts 

was analyzed for the following lakes designated as acid sensitive: 

Lake Area 

Deep Lake Bridger Wilderness Area 

Black Joe Lake Bridger Wilderness Area 

Hopps Lake Bridger Wilderness Area 

Upper Frozen Lake Bridger Wilderness Area 

Lazy Boy Lake Bridger Wilderness Area 

Ross Lake Popo Agie Wilderness Area 

Lower Saddlebag Lake Glacier Lakes Ecosystem Experiments Site 

West Glacier Lake Mt. Zirkel Wilderness Area 

Lake Elbert Mt. Zirkel Wilderness Area 

Seven Lakes Mt. Zirkel Wilderness Area 

Summit Lake Mt. Zirkel Wilderness Area 

Island Lake Rawah Wilderness Area 

Kelly Lake Rawah Wilderness Area 

Rawah Lake #4 Rawah Wilderness Area 

A regional emissions inventory of industrial sources located within the far-field modeling domain 

was used in the cumulative impact analysis. Oil and gas wells permitted and approved between 

January 1, 2001 and March 31, 2004 were included in this inventory. Impacts from sources in 

operation prior to this date were assumed to be included in regional background concentrations. 

Potential sources currently being analyzed in Wyoming under BLM and Forest Service EIS 

processes were also included in the regional emissions inventory, providing that such sources had 

been defined and analyzed sufficiently to yield a project emission inventory by March 31, 2004. 

Modeled impacts were compared to applicable Class I and Class II increments, and to the AAQS 

when background pollutant concentrations were added. When all pollutants were analyzed, the 

Bridger Wilderness Area proved to be the most sensitive area with regards to potential impacts. 

However, the modeled impacts were well below their respective ambient air increment 

concentrations although an expansion of annual SO2 increment was predicted. Predicted total 

ambient concentrations (background concentrations added to modeled impact) were also below 

the respective state AAQS for each sensitive receptor modeled. 

4­8 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Annual deposition fluxes of sulfur and nitrogen at sensitive lake receptors predicted by the far-field 

model were used to estimate the change in ANC. A Forest Service screening methodology (Fox 

1989) was used for this estimate, which indicated that cumulative emissions would cause less 

than a 0.23% change in ANC with the exception of Upper Frozen Lake located in the Bridger 

Wilderness Area, where the predicted ANC change was 2.41%. However, the model indicted that 

the Seminoe Road Project would not contribute to the cumulative ANC change for any analyzed 

sensitive lake. 

Impacts to visibility (regional haze) at Class I and sensitive Class II areas were analyzed using the 

CALPUFF modeling system (TRC 2004). This model predicted concentrations of PM10, PM2.5, 

SO4 and NO3, which, in turn, were used to calculate the change in atmospheric light extinction. 

Change in atmospheric light extinction relative to background conditions is used to assess 

regional haze. Natural background visibility conditions were obtained from FLAG (TRC 2004), a 

federal land managers’ report on air quality related values, and data measured at the Bridger 

Wilderness (Wyoming), Mount Zirkel Wilderness area (Colorado), and Rocky Mountain National 

Park (Colorado). 

Analysis thresholds for atmospheric light extinction are set forth in FLAG (TRC 2004) at 5% and 

10% of the reference background visibility or 0.5 and 1.0 deciview (dv) for project sources alone 

and cumulative impacts, respectively. There are no applicable local, state, tribal or federal 

regulatory visibility standards; however, the BLM does consider a 1.0 dv change to be a significant 

adverse impact. 

The far-field modeling analysis predicted that the Seminoe Road Project would not contribute to 

any visibility impairment at Class I and sensitive Class II areas. 

FLAG and IMPROVE background visibility data were used to analyze visibility impacts at each 

Class I and sensitive Class II area. Direct visibility impacts from the Seminoe Road Project alone 

were predicted to be below the 0.5-dv threshold at all Class I and sensitive Class II areas. 

Although the cumulative visibility analysis for all regional sources (including the Seminoe Road 

Project) revealed that there could be 4 days per year (IMPROVE) and 1 day per year (FLAG) 

when visibility impacts were greater than the 1.0-dv threshold for the Bridger and Popo Agie 

Wilderness areas in western Wyoming, it was determined that the Seminoe Road Project would 

not be a major contributor to these few visibility exceedances. Impacts from the Seminoe Road 

Seminoe Road Gas Development Project 4­9
Draft Environmental Impact Statement November 2005

Project were predicted to be below the 0.04 dv visibility significance threshold for all days where 

the cumulative visibility impacts were estimated to be 1.0 dv or greater (TRC 2004). 

4.1.4 Effects of Alternative B (Proposed Action)

The air quality effects of Alternative B would be the same as addressed in Section 4.1.2, Effects 

Common to All Action Alternatives, and Section 4.1.3, Cumulative Impacts. 

4.1.5 Effects of Alternative C (Pipeline to Reservoir)

Under Alternative C, as a means to compare emissions to the electrified scenario set forth in 

Alternative B, the compressors and the down-hole pumps would be gas powered. Emissions for 

down-hole pump engines, vehicle diesel engines, and gas-fired compressor engines were 

modeled utilizing AERMOD, and, as expected, emissions of NOx, CO and formaldehyde would be 

greater for Alternative C than for Alternative B. See Table 4.1-4, Maximum Modeled NO2 and 

CO Impacts – Alternative C. 

Table 4.1-4, Maximum Modeled NO2 and CO Impacts – Alternative C 

Pollutant Averaging 

Time 

Direct 

Modeled 

(μg/m3) 

PSD Class II 

Increment 

(μg/m3) 

Background 

(μg/m3) 

Total 

Predicted 

(μg/m3) 

WAAQS 

(μg/m3) 

NAAQS 

(μg/m3) 

NO2 Annual 11.1 25 3.4 14.5 100 100 

CO 1-hour 101.7 None 3,336 3,438 40,000 40,000 

8-hour 46.6 None 1,381 1,428 10,000 10,000 

Potential formaldehyde emissions from compressor engines, down-hole well pumps and diesel 

truck emissions were also modeled. Short-term impacts were compared to Reference Exposure 

Levels (REL) developed by the National Institute for Occupational Safety and Health. Long-term 

impacts of formaldehyde are compared to the EPA Reference Concentrations for Chronic 

Inhalation (RfC). Table 4.1-5 Maximum Modeled Formaldehyde Impacts. 

Table 4.1-5, Maximum Modeled Formaldehyde Impacts 

Averaging Time 

Modeled Concentration 

(μg/m3) 

Comparison Threshold 

(μg/m3) 

1-hour 4.07 94 REL 

Annual 0.027 9.8 RfC 

Because formaldehyde is a suspected carcinogen and long-term exposures to this constituent can 

increase latent cancer risk over a 70-year lifetime, possible exposure impacts to the residence 

nearest the EIS analysis area (located in NW1/4, Section 12, T22N, R85W) were evaluated. 

EPA’s Unit Risk Factors (RF) were used to analyze cancer risk (TRC 2004). Results of this 

4­10  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

analysis are set forth in Table 4.1-6, Long-term Formaldehyde Cancer Risk Analysis, and the 

results indicate an extremely low cancer risk, nearly less than a one-in-a billion risk. 

Table 4.1-6, Long-term Formaldehyde Cancer Risk Analysis 

Analysis HAP Constituent 

Modeled 

Concentration 

(μg/m3) 

Unit Risk Factor 

1/(μg/m3) 

Exposure 

Adjustment 

Factor 

Cancer Risk 

MLE Formaldehyde 0.027 1.3 x 10-5 0.0949 3.31 x 10-8 

Even with gas-powered compressors and down-hole well pumps, the cumulative air quality effects 

of Alternative C would essentially be the same as discussed in Section 4.1.3, Cumulative Impacts. 

There would be no visibility impairment at Class I and sensitive Class II areas as a result of the 

Seminoe Road Project, Alternative C. 

4.1.6 Effects of Alternative D (Underground Injection)

The air quality effects of Alternative D would be the same as addressed in Section 4.1.2, Effects 

Common to All Action Alternatives, and Section 4.1.3, Cumulative Impacts. 

4.1.7 Potential Monitoring and Mitigation

No site specific monitoring is proposed for the Seminoe Road Project. The mitigation measures 

addressed in Section 2.8.9, Air Quality, should be sufficient for the project. 

Predicting cumulative air quality impacts for future oil and gas development in Wyoming continues 

to be problematic for the BLM. Past EIS analyses often over-predict cumulative impacts because 

recent and spatially relevant air quality and meteorological data is lacking. BLM and state of 

Wyoming land managers should consider installing a statewide network of PM10 meteorological 

stations, particularly in regions of high oil and gas development. The data from these new 

monitoring stations would be effective to improve future air quality analyses and permitting efforts 

in Wyoming. 

4.2 Soils

Soils Impact Significance Criteria: Soils impacts would be considered significant if the 

Proponent failed to salvage available quantities of soil for reclamation and soil disturbance caused 

a loss of soil productivity and/or created a sustained increase in erosion above normal conditions 

such that excessive sediments entered Seminoe Reservoir or North Platte River. 

Seminoe Road Gas Development Project 4­11
Draft Environmental Impact Statement November 2005

4.2.1 Effects of Alternative A (No Action)

Under the no action alternative, the EIS analysis area would essentially remain in its endemic 

state supporting current land uses. The Pilot Project operations could continue under the no 

action alternative. 

4.2.2 Effects Common to All Action Alternatives

Table 4.2-1, Soil Impacts by Alternative depicts the acreages of disturbances to sensitive soils 

(saline/sodic soils, shallow soils and erodible soils) associated with each action alternative. 

Table 4.2-1, Soil Impacts by Alternative 

Soil Category1 

Area Within EIS 

Analysis Area 

(acres) 

Portion of EIS 

Analysis Area 

(%) 

Area Disturbed 

Alternative B 

(acres) 

Area Disturbed 

Alternative C 

(acres) 

Area Disturbed 

Alternative D 

(acres) 

Shallow Soils2 49,280 36 2,460 2,530 2,460 

Saline/Sodic Soils3 38,720 28 1,940 2,010 1,940 

Erodible Soils4 25,920 19 1,300 1,340 1,300 

Overlap of the Above 

Three Soil Cagegories5 6,400 5 320 350 320 

Notes: 

1. These soil categories occur throughout the EIS analysis area; they are not additive as they overlap on each 

other in many areas. 

2. See Figure 23, Saline and Sodic Soils. 

3. See Figure 25, Shallow Soils. 

4. See Figure 26, Erodible Soils. 

5. See Figure 27, Areas of Sensitive Soils Concentrations. 

It is assumed that no soils would be disturbed under Alternative A beyond those disturbed under the previouslyapproved Pilot Project and gas pipeline to Walcott. 

During the construction phase, facility and utility sites would be cleared of vegetation, graded or 

excavated to specifications, and the construction/burial of facilities and utilities completed. Surface 

soils would be salvaged and windrowed/stockpiled along the borders of all proposed disturbed 

sites. Subsoils and other subgrade materials would remain in place for the life of the project, 

excepting for utility line burial disturbances where the subsoils would be excavated and replaced 

within a relatively short time span. Erosion and sediment control features would be constructed as 

required. The construction phase of the project would be completed with the implementation of an 

interim reclamation plan applied to those areas not required for the production phase of this 

project. This acreage includes all of the disturbed areas associated with utility line burial and the 

majority of the acreage disturbed in association with well pad and access road construction. Soil 

reapplication would occur during the same year as construction to be followed by revegetation at 

the beginning of the next recognized planting season. 

4­12 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

The operations phase of this project would involve the extraction of natural gas from well pad 

facilities, the use of access roads, and the operation of compressor facilities. At the close of 

operations, aboveground facilities would be removed, disturbed sites regraded to the desired 

contours, stockpiled soil replaced, and revegetation completed. Erosion and sediment features 

would remain in place until no longer needed. 

The linear nature of the proposed project, coupled with surficial limitations of many proposed 

disturbances leaving a relatively intact subsurface soil profile, would increase the potential for 

overall reclamation as compared to broader-type disturbances. Desirable plant species invasion 

from adjacent undisturbed areas would be enhanced and the time required to achieve successful 

reclamation potentially shortened. 

Impacts to the soil resource resulting from these proposed disturbances include those that would 

affect the chemical, physical, and microbial nature of the endemic soils as well as the volumes 

available for reclamation. Soil chemical parameters would be permanently modified as a result of 

the proposed soil salvage program. Soil surface horizons would be mixed during salvage resulting 

in a blending of characteristics as compared to the soils in their natural state. Such characteristics 

include pH, salinity, and fertility. Soil chemistry would also be modified through soil stockpiling as 

anaerobic conditions within the stockpiles develop, depending on stockpile size, depth, and 

longevity. A number of soil physical characteristics such as structure, texture, and rock fragment 

content would be permanently modified through blending during surface soil salvage and 

replacement operations. Given that only surface soils would be salvaged/stockpiled, individual 

disturbances would be comparatively small in any one area, and that little mixing of divergent soil 

types would likely occur, the impacts to soils associated with salvage and replacement activities 

are considered to be limited in duration and intensity. The surface soil horizons that would be 

mixed at any one site would likely be similar in terms of both chemical and physical characteristics 

and, given the site-specific soil volumes involved, would not likely result in a negative impact in 

terms of reclamation potential. Revegetation plans prepared on a site-specific basis should 

adequately address these soil chemical and physical concerns and limit the impacts of soil 

salvage and replacement to the short-term following soil reapplication on disturbed surfaces. 

Isolated spill accidents, should they occur, would result in minor soil contamination from oils, solvents, 

etc. (See Section 4.15, Accidents and Spills) Spills would normally result in soils deemed unsuitable 

for reclamation. Soils impacted by chemical spills would be excavated and disposed of in a licensed 

Seminoe Road Gas Development Project 4­13
Draft Environmental Impact Statement November 2005

landfill facility approved by the BLM. The volume of soil subject to spills should be limited, however, 

given the plan to salvage suitable soils prior to operational disturbances and the proposed 

implementation of a SPCC Plan. No impact to the revegetation potential of the soil resource is 

anticipated. 

Compaction, particularly along access road disturbances, would likely reduce the aeration, 

permeability, and water-holding capacity of impacted soils from construction through the operations 

phase of this project. Ripping and similar surface manipulations are proposed as a part of the 

reclamation plan to address compaction concerns. The effects of compaction can be reduced once 

these techniques are properly applied. 

Soil microbial populations would likely change with a potential overall loss of nitrifying-type species 

as surface soils are salvaged and placed in stockpiles. This impact would be most notable in 

larger stockpiles where surface soils supporting microbial populations are buried to depths 

dominated by anaerobic conditions. The loss of such species would be less notable in smaller 

stockpiles windrowed along access roads or well pad boundaries where aerobic conditions 

dominate. Impacted soil microbial populations should reestablish readily over time following soil 

reapplication through natural invasion from adjacent undisturbed soils given the small acreage 

impacted in any one area and/or the linear nature of the road and utility corridor disturbances. The 

reclamation techniques to be applied would also aid in reestablishing soil microbial populations as 

reclaimed plant communities develop. This is a generally accepted premise based on 

observations of reclaimed mine areas in the Northern Great Plains where stockpiled soil has been 

respread and revegetation has been successful. This is considered to be a short-term, mitigable 

impact. 

4.2.2.1 Saline/Sodic Soils

Impacts to saline and/or sodic soils (Figure 23, Saline and Sodic Soils) center around the 

suitability of these soils for reclamation and the availability of sufficient quantities of soil material 

for salvage and reapplication. As noted previously, these soils often exhibit droughty profiles due 

to high salinity levels and may also be subject to decreased soil aeration, infiltration, and 

permeability under high sodium levels when coupled with clayey soil textures. Soil stockpile 

stabilization and revegetation plantings can be hindered in the face of such edaphic 

characteristics resulting in reduced seed germination, plant establishment, and growth. The low 

average annual rainfall characteristic of this region further exacerbates this condition. However, 

4­14 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

the soils exhibiting these constraints, for the most part, readily support adapted, native vegetation 

communities on site. It can be assumed that with sufficient soil depths, efficient soil handling, and 

the planting of adapted species, reclamation of these disturbances can be achieved in the shortterm. 

Where saline and/or sodic soil constraints are coupled with a shallow soil condition, reclamation 

goals would be more difficult to achieve in the short-term. Soil handling efficiencies should not be 

affected given dominant slope angles. However, a shallow soil depth replaced over bedrock, or 

less weatherable parent material, would likely enhance a droughty soil profile already constrained 

by soil chemistry and regional climatic influences. These soil conditions do, however, support saltand drought-tolerant plant communities on site so it is assumed that the reclamation of 

disturbances characterized by these conditions can be achieved through time. 

These soils are only rarely found on slopes exceeding 25%. 

4.2.2.2 Soils Overlying Steep Slopes

Soil map units overlying steep slopes are characterized, all or in part, by water erosion 

constraints. Shallow soils are also common while few steep slope soils exhibit saline or sodic 

profiles. A primary concern with respect to impacts to steep slope soils (Figure 24, Steep Slope 

Soils) is construction and reclamation equipment efficiencies as related to soil handling. Soil 

salvage and handling efficiencies on slopes up to and including 25% are not typically constrained 

to a great degree unless influenced by shallow soil conditions, extreme topographic variations, or 

high surface coarse fragment cover. The majority of slopes proposed for disturbance are less 

than 25%. Conversely and depending upon slope gradient, equipment efficiencies can be 

curtailed on slopes greater than 25%. A reduction in efficiencies can, in turn, result in a 

displacement of soil materials rendering them unavailable for salvage and, in a disturbed state, 

subject to increased water and wind erosion. Stockpiled soils and soils respread over regraded 

disturbances on steep slopes are also subject to increased runoff and higher erosion potentials 

until soil stabilization goals have been met. Mulching may be required to successfully stabilize 

these disturbed soils and to meet vegetation establishment goals. 

Impacts to steep slope soils are considered to be mitigable and short-term, assuming that proper 

soil handling and revegetation techniques are employed. It is likely, however, that steep slope 

Seminoe Road Gas Development Project 4­15
Draft Environmental Impact Statement November 2005

disturbance footprints would be visible for some years beyond the point when they are 

successfully stabilized and vegetation productivity is restored. 

4.2.2.3 Shallow Soils

Shallow soils (Figure 25, Shallow Soils) are more susceptible to the negative affects of 

increased erosion due to the limited soil material initially available and capable of supporting 

vegetation. Soil salvage and reapplication operations occurring on more gentle slopes could be 

conducted in shallow soil situations with adequate efficiencies. Conversely, salvage/reapplication 

operations conducted under steep slope conditions would potentially be less efficient. Soil 

stockpile stabilization would be critical for disturbances located in shallow soil situations to ensure 

that sufficient soil material is stockpiled and available for reapplication. Similarly, surface 

stabilization following soil reapplication would be important to be certain that a sufficient depth of 

soil remains over disturbed sites to achieve site stabilization and plant establishment goals. 

Shallow soils rarely exhibit saline or sodic profiles. 

Impacts to shallow soils, where soil salvage/replacement and revegetation techniques can be 

applied efficiently, are considered to be short-term and mitigable. Impacts to shallow soils where 

soils could not be salvaged or replaced due to equipment inefficiencies would be viewed as a 

long-term, negative impact. 

4.2.2.4 Highly Erodible Soils

Soil map units characterized by slight to severe and severe water erosion potentials are common 

across the project area (Figure 26, Erodible Soils). The vast majority of soils overlying steep 

slopes are included in either one of these classifications as are units on more gentle slopes 

subject to high runoff potentials. These soils may also be shallow and/or saline/sodic. Soil map 

units characterized by slight to severe or severe wind erosion potentials are not common on site. 

Soils subject to this hazard typically exhibit sandy surface soil textures and may support a 

comparatively sparse vegetation community. 

Water or wind erosion left unchecked can result in a loss of stockpiled soils suitable for 

reapplication that, in turn, can reduce the revegetation success potential of any disturbed site. Soil 

erosion occurring on recently planted or establishing vegetation communities can also have 

detrimental affects on revegetation success, particularly on steeply sloping sites. Erosion 

potentials are typically highest during the construction phase of this type of project, falling in 

4­16  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

severity as interim revegetation, soil stockpile, and erosion control activities are completed. 

Hazards would again rise at specific sites as the project is terminated and regrading/resoiling 

operations are initiated. Erosion hazard potentials would then again fall as the reapplied soils are 

stabilized and vegetation communities become established. 

The Proponent has committed to a number of site management and construction techniques, in 

addition to soil salvage and concurrent reclamation that would serve to reduce the erosion 

hazards. These activities include using existing roads for access purposes to the degree possible, 

applying BLM “best management practices” during construction and revegetation activities, 

minimizing new disturbances to the acreage necessary to complete construction and operations, 

and employing road surfacing as a part of overall road maintenance. 

Overall, impacts to highly erodible soils on more gentle slopes are mitigable and short-term 

assuming the application of the appropriate construction and reclamation techniques. The 

confounding factors of salinity/sodicity, steep slopes, and/or shallow soil depths added to high 

erosion hazards would inhibit reclamation potentials to varying degrees and increase the time 

required to achieve site stabilization and reclamation objectives. 

4.2.2.5 Indirect Effects Common to All Action Alternatives

There are no indirect effects associated with the Seminoe Road Project for soils. 

4.2.3 Effects of Alternative B (Proposed Action)

Impacts to soils of the development area under Alternative B would include those common to all 

action alternatives plus those associated with the release of process water down project area 

drainages. Points of discharge are shown on Figure 12, Produced Water Discharge Points – 

Alternative B. Process water contains varying levels of salts and sodium that would be introduced 

into existing soil profiles over and above those levels existing normally. As noted in Section 4.4, 

Surface Water, the approximate average concentration for sodium (371 mg/l) in the produced 

water is higher than the concentration in the North Platte River and Seminoe Reservoir (42 mg/l). 

The introduction of salts and sodium, as well as the additional water itself, would give rise to a soil 

continuum having the potential for supporting a different array of plant species than is normal for 

the drainages proposed to be affected. This would probably also be true for the playa areas where 

produced water would be discharged and allowed to infiltrate and evaporate. This can also 

currently be seen on site where process water has been released into Pool Table Draw. The soils 

Seminoe Road Gas Development Project 4­17
Draft Environmental Impact Statement November 2005

exhibit, at least temporarily, an enhanced soil moisture regime supporting a fairly diverse array of 

wetland-classed plant species. Saltmarsh bulrush (Boboschoenus maritimus) is occasionally 

present indicating, where this species exists, a potentially saline soil condition though there is no 

direct evidence of salinity increases in the soil materials present which have been subject to 

produced water discharges since 2001. It can be assumed that, with the release of process water 

down the drainages during operations, soil moisture regime characteristics as well as soil salt and 

sodium levels would be enhanced. With the close of operations, process water releases would be 

terminated. It is likely that soil moisture regimes would return to pre-disturbance conditions. 

However, any increase in salt or sodium levels would remain. The potential increase in soil salinity 

and sodicity that could result cannot be accurately calculated. See Section 4.6.3, Effects of 

Alternative B (Proposed Action) for a summary of such impacts to the vegetation resource. 

The drainages to be affected may also experience increased erosion of the channel bottoms and 

side slopes. The degree of erosion would depend, typically, on the amount, velocity, and timing of 

discharges as well as the condition of the channels. Where such channels are now vegetated or 

are overlain by a gravel/cobble surface, all or in part, erosion would be curtailed. 

4.2.4 Effects of Alternative C (Pipeline to Reservoir)

Impacts to soils across the EIS analysis area, as a whole, would be identical to those described 

for Alternative B (Proposed Action) under this alternative. Impacts to drainage-way soils not 

affected to date, conversely, would be eliminated since produced water would be conveyed to 

Seminoe Reservoir via a buried pipeline (see Figure 14, Direct Discharge into Seminoe 

Reservoir – Alternative C). Revegetation of these disturbances would occur following 

construction and be completed during the first appropriate planting season. Assuming the proper 

vegetation techniques are applied, this impact to soils would compare to that associated with the 

interim reclamation of other utility lines to be constructed. 

Although the water conveyance pipeline would be designed and installed to prevent leaks, there 

remains a possibility, albeit remote, that any pipeline constructed to convey water to the reservoir 

could develop leaks resulting in process water entering the soils surrounding this utility. Although 

produced water is slightly saline and sodic, no impact to soils would be expected in terms of the 

soil’s capability to support native plant communities if a leak is quickly prepared. If the pipeline is 

surface-laid, any leaks could be readily identified and repaired. Leaks in buried water pipelines are 

more difficult to detect, and repairs would be made by excavating to the pipeline, thus disturbing 

4­18  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

ground at and surrounding the area of the leak. This short-term impact would be considered to be 

of limited magnitude and duration assuming the leak is repaired and the construction area 

revegetated with the appropriate plant species in a timely manner. 

4.2.5 Effects of Alternative D (Underground Injection)

The surface disturbances proposed under this alternative, and the potential impacts to the soil 

resource, are the same as for Alternative B (Proposed Action) with one exception. Since produced 

water would be injected underground, soils overlying drainage-ways not affected to date would not 

be subject to potential impacts from produced water. Injection wells would be located in areas 

already affected by produced water treatment facilities (see Figure 16, Underground Injection 

of Produced Water – Alternative D). The physical and chemical characteristics of these soils 

would remain at baseline levels. 

4.2.6 Cumulative Impacts

In the past, soil resources in the EIS analysis area has been impacted through road building, 

electrical transmission line construction, mining, and pipeline installation. The implementation of 

any of the proposed action alternatives could result in a loss of soil productivity and the potential 

for increased soil erosion. The potential for soil erosion from the project disturbance is not 

expected to result in any major increases in sedimentation of area drainages. The contribution by 

the Seminoe Road Project disturbances to overall soil erosion within the various watersheds 

would be small given erosion/sediment control techniques and revegetation activities to be 

employed and the relatively minor total project disturbance (less than 5% of the EIS analysis area) 

proposed. 

4.2.7 Potential Monitoring and Mitigation

When considering natural gas production requirements, the location of proposed facilities would 

be sited to avoid or minimize, to the degree possible, disturbances to sensitive soils, including 

cryptobiotic soils. While it is not possible to avoid sensitive soils entirely given their occurrence 

over the project area, a minimization approach would serve to decrease the potential for erosion 

and increase the potential for successful and timely reclamation. Minor siting modifications in 

sensitive soil areas targeting lesser slope angles or higher quality soils would result in lesser and 

more manageable impacts to the soil resource. 

Seminoe Road Gas Development Project 4­19
Draft Environmental Impact Statement November 2005

4.3 Geology

Geology Impact Significance Criteria: Geology impacts would be significant if the project 

resulted in landslides or subsidence. 

4.3.1 Effects of Alternative A (No Action)

Under the no action alternative, the Pilot Project could continue; however, natural gas would not 

be extracted from the remainder of the EIS analysis area. The potential to recover the natural gas 

resource at some point in the future would remain. 

4.3.2 Effects Common to All Action Alternatives

There would be negligible effect to the geologic resources as a result of drilling activities and 

extraction of natural gas. Although the gas resource would be extracted, the existing geologic 

structure and lithology in the area would not be altered. The potential recoverability of any oil and 

gas resources present in the geologic formations below the targeted coal seams would also be 

unaltered. In addition, there would also be no indirect effects to the geologic resources for any of 

the alternatives. 

The potential of the project to create landslides is unlikely. If an earthquake of the typical historic 

intensity (2.0 to 4.1 magnitude) occurs in the vicinity of the Seminoe Road Project, no property or 

equipment destruction is expected. 

In addition, dewatering activities would not cause aquifer compression or ground subsidence as 

the production coal formations (Medicine Bow/Fox Hills and Mesaverde formations) would 

continue to exist under confined hydraulic conditions, where the potentiometric surface (pressure 

head of the ground water) would remain above the top of the formations. Although the pressure 

head in the coals would be reduced during dewatering activities to promote release of natural gas, 

the formations would remain saturated, albeit under less hydraulic pressure. Therefore, aquifer 

compression and ground subsidence would not occur. 

Given projected depths of gas extraction at the Seminoe Road Project, the continued pressure 

head on the target coal zones, and the drilling and well completion techniques, the potential for 

fugitive natural gas seepage to reach surface outcrops or affect local wells is expected to be low. 

4­20  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

The potential of the Seminoe Road Project activities to disturb or damage paleontological 

resources is low as there are no known significant fossil-bearing localities in the area. 

On the eastern side of the EIS analysis area, or in undeveloped isolated leases within the analysis 

area, it is possible that natural gas production could drain gas resources from outside the active 

extraction area; however, given the planned 160-acre well spacing and with proper well 

connection techniques, the well drainage is expected to be negligible. In addition, the BLM and 

WOGCC would monitor drilling activities 

4.3.3 Effects of Alternative B (Proposed Action)

The effects of Alternative B would be the same as those described in Section 4.3.2, Effects 

Common to All Action Alternatives. 

4.3.4 Effects of Alternative C (Pipeline to Reservoir)

The effects of Alternative C would be the same as those described in Section 4.3.2, Effects 

Common to All Action Alternatives. 

4.3.5 Effects of Alternative D (Underground Injection)

Effects of Alternative D on geologic resources would be similar to that of Alternatives B and C, 

except that underground injection would be used for disposal of produced water. Underground 

injection would need to be permitted in accordance with federal and state regulations, and 

pressure buildup in injected geologic zones could cause seismic activity to occur. However, any 

impact from such seismic activity is expected to be low, even negligible. 

4.3.6 Cumulative Impacts

As explained in Appendix E, Regional Activity, underground and surface coal mining activities 

have occurred in the Hanna Basin over the past century. The targeted coal zones for mining 

activities were the sub-bituminous and bituminous coals occurring in the Tertiary age Hanna 

Formation; the Hanna Formation is located stratigraphically well above the targeted Medicine 

Bow/Fox Hills and Mesaverde coals, which are the extraction zones for the Seminoe Road 

Project. See Figure 29, General Stratigraphic Column and Geologic Cross-Section A-A’. 

Historic attempts to develop oil resources within and surrounding the EIS analysis area have not 

been successful. Although numerous exploration wells have been drilled, no economic oil 

Seminoe Road Gas Development Project 4­21
Draft Environmental Impact Statement November 2005

reserves were discovered. There are no existing oil wells within the EIS analysis area that would 

be disturbed by the planned Seminoe Road Project. North of the Seminoe Road Project, on a 

topographic feature known as “Windy Ridge,” a single gas well, which was reported to have been 

productive, is currently capped (BLM, personal communication, 2004). Activities at the Seminoe 

Road Project should have no impact to this “Windy Ridge” capped gas well. 

4.3.7 Potential Monitoring and Mitigation

If any paleontological resources are discovered during construction activity at the Seminoe Road 

Project, further operations would be stopped within the area of the discovery, and the BLM 

authorized officer would be notified to ensure that appropriate protection and/or mitigation could 

be implemented. 

4.4 Surface Water

Surface Water Impact Significance Criteria: Impacts to surface water would be considered 

significant if: 

� Produced water discharge or surface disturbance negatively affects the beneficial uses in 

North Platte River, Seminoe Reservoir or downstream of Seminoe Reservoir; 

� Produced water discharge results in violation of Wyoming Pollutant Discharge Elimination 

System (WYPDES) permit conditions; 

� Produced water discharges degrade Class I waters in the Miracle Mile such that the 

beneficial use (blue ribbon trout fisheries) is negatively affected; 

� Surface disturbance or erosion from project actions causes grazing allotments within the 

project area to fail standards for healthy rangelands for public lands (BLM 1997); 

� Surface disturbance from roads and construction activities and/or from project discharges 

increase sediment loads into Seminoe Reservoir above background conditions; and 

� Produced water discharge causes erosion in the ephemeral and intermittent drainages in 

the EIS analysis area beyond the erosion expected to occur under natural conditions. 

A surface water-quality mixing model (mixing model) was prepared to assess potential water 

quality impacts to the Seminoe Reservoir and the North Platte River both upstream and 

downstream of the Seminoe Reservoir (HydroGeo 2003b). This mixing model was adapted from 

4­22 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

an EPA model developed for the Powder River Basin in northeast Wyoming and was altered to fit 

the site-specific conditions of the Seminoe Road Project. A discussion of the mixing model 

assumptions and general protocol is set forth in Appendix J, Overview of Surface Water Mixing 

Model. The surface water impact analysis results presented from this model were used to 

compare the relative impacts from various activities under the identified alternatives. WDEQ, 

Water Quality Division, issues permits for surface discharge and determines conditions governing 

timing, potential treatment or other conditions designed to protect Wyoming waters (i.e. NPDES 

permits, the name was recently changed to WYPDES permits). See Appendix D, Agency 

Jurisdictions (Permits and Approvals). 

In addition to the surface water quality model, baseline data were collected in the Seminoe Road 

Project area for water quality, vegetation, channel stability and other factors that may be 

influenced by Seminoe Road Project actions. This information was presented in Chapter 3, 

Affected Environment, and reports referenced throughout this document. The Pilot Project 

contains many of the elements that are proposed in the alternatives, most notably road/pad 

construction, interim and final reclamation, surface water discharge, produced water quality, 

treatment systems, a reconstructed stock pond that collects project and runoff waters, and water 

quality and flow data collected by the Proponent and the BLM. Information and data from the Pilot 

Project are presented throughout this section to aid in the analysis of project alternatives. 

4.4.1 Effects of Alternative A (No­Action)

Pilot Project operations would continue under the no action alternative, with produced water being 

discharged into Pool Table Draw under the terms and conditions of a NPDES permit issued by the 

WDEQ Water Quality Division. See Table 4.4-1, Pilot Project NPDES Limits. The Pilot Project has 

not caused any measurable water quality effects to the Seminoe Reservoir or to the Miracle Mile 

stretch of the North Platte River; however, it has increased in-channel erosion in Pool Table Draw. 

Table 4.4-1, Pilot Project NPDES Limits 

Daily Discharge at any Discharge Point 1.5 cfs 

Chloride 46 mg/l 

Dissolved Iron 0.2 mg/l 

Dissolved Manganese 0.621 mg/l 

Specific Conductance 2,000 μmhos/cm 

Sulfate 3,000 mg/l 

Total Arsenic 0.0014 mg/l 

Total Barium 1.8 mg/l 

Total Dissolved Solids 5,000 mg/l 

Total Petroleum Hydrocarbons 10 mg/l 

Total Radium 1.0 pCi/l 

Seminoe Road Gas Development Project 4­23
Draft Environmental Impact Statement November 2005

Recently completed acute Whole Effluent Toxicity tests (WET tests) show no impacts of produced 

water on aquatic organisms; all mortality is insignificant as compared to a laboratory standard or to 

other sampling points. WET testing was performed by Energy Laboratories, Billings, Montana. 

Samples were collected from five locations by HydroGeo. The locations tested were: 

� DS-3 Discharge, pre-aeration, pre-treatment 

� DS-3 Discharge at bubbler, post-treatment 

� AMP-4 (old POC), mouth of Pool Table Draw 

� AMP-2, Seminoe Reservoir, Coal Creek Arm 

� North Platte River, Miracle Mile at Bridge 

After discharge, de-gassing of project-produced water causes a 5-10% increase in the produced 

water’s pH. In addition, upon being discharged into drainage channels, the quality of the produced 

water can be influenced by the channel sediments over and through which the water flows; the 

degree of this influence is seasonally variable (See Appendix I, Monitoring Results for 

Seminoe Road Pilot Project). In general, during warmer months, produced water flowing in Pool 

Table Draw has experienced concentration increases in TDS (15 to 20%), iron (200 to 400%) and 

conductivity (15 to 20%), while sustaining a 10 to 15% reduction in SAR values. (HydroGeo 2004) 

Although Pilot Project produced water is subject to energy dissipation measures before being 

released to the surface (See Figure 11, Water Treatment Facilities Layout), constant 

downstream flow tends to saturate channel soils and sediments, which creates conditions more 

conducive to erosion than dry soils and sediments. Where the drainage gradient increases, 

surface roughness changes and/or soils have less structure; drainage channels are subject to 

downward cutting or bank erosion as the drainage system seeks equilibrium. 

Pool Table Draw, like other drainages in the EIS analysis area, has erosion features along 

portions of the drainage, such as headcuts and bank erosion. See Figure 38, Pool Table Draw 

Photographs. These features in the lower portion of Pool Table Draw include a deep gulley in the 

high pool of the reservoir, a narrow incised headcut dropping 3-5 feet and a number of small nick 

points as the channel drops to the elevation of the headcut (see Appendix I, Monitoring Results 

for Seminoe Road Pilot Project). The constant flow of Pilot Project produced water has 

exacerbated and, in several places, accelerated the natural erosion processes. Heavy runoff from 

4­24 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

thunderstorms, including one in August 2003, intensified the erosion, especially the downcutting 

and bank erosion in the drainage. See Figures 35 and 36, Hydrologic Process and 

Geomorphic Cycle (Parts I and II). 

For several years, given drought conditions and fluctuating (downward trending) water levels, 

Seminoe Reservoir has been below its full pool level. Immediately downstream of the area where 

the Pool Table Draw drainage channel intersects with the full pool level of the Seminoe Reservoir, 

headcutting and gully formation is more prevalent. See Figure 38, Pool Table Draw 

Photographs and Figures 35 and 36, Hydrologic Process and Geomorphic Cycle (Parts I 

and II). 

The Pilot Project ROD, issued in 2001 by the BLM, requires mitigation to minimize project related 

channel erosion impacts (BLM 2001b). In-channel mitigation is expected to require at least one 

major drop structure and at least 5 small armoring structures for nick points (small vertical drops 

in the channel elevation) to stabilize the system; this may change as the plans are finalized. These 

major drop structures can be built using sheet piling (interlocking corrugated sheet metal), rock 

gabion structures (metal wire reinforced baskets for rock aggregate), large rock placement without 

gabions to form vortex weirs, and/or concrete weirs. These structures require heavy equipment 

such as bulldozers, backhoes, front-end loaders, haul trucks etc. and would need the construction 

of temporary roads or the upgrade of existing two tracks to access construction sites and haul 

material such as rock used for rip-rap. The small armoring structures would include the installation 

of fabric anchored into the drainage sides and rock rip-rap to reduce channel energy. 

4.4.2 Effects Common to All Action Alternatives

All action alternatives would produce approximately 101,000 acre-feet of water from coal seams 

over the life of the project. Water production would begin in year 1 and conclude in year 30, with 

maximum water production in year 7. See Figure 41, Project Water Production Schedule. The 

actual effects of produced water disposal would vary amongst the action alternatives. 

Erosion and sedimentation would be the predominant common effect to all action alternatives; 

however, the amount and extent of such erosion and sedimentation would vary with each 

alternative, as each action alternative has a different level of disturbance and a different means of 

produced water disposal. 

Seminoe Road Gas Development Project 4­25
Draft Environmental Impact Statement November 2005

Development and construction activities (well pads, roads, utility installations) are potential 

sources of soil erosion and increased sediment loading to area drainages. The potential for 

erosion and sediment loading below disturbed areas would be the greatest during the initial 

construction phase. During production operations, potential erosion would decrease due to less 

surface disturbance and the implementation of interim reclamation activities. 

As described in Section 2.4, Alternative B – Proposed Action, the Proponent has proposed that 

approximately 60% of the original construction disturbance would be reclaimed; this is called 

interim reclamation. See Table 2-1, Preliminary Estimate of Surface Area Disturbance. Road 

and well pads used for production purposes would be graveled. Sediment control measures are 

set forth in Section 2.8.12, Water Resources, and reclamation techniques and measures are 

discussed in Section 2.7, Proponent Committed Reclamation Measures, and Appendix F, 

Reclamation Plan. 

The proposed interim reclamation (and final reclamation) would help protect surface water 

resources from additional sedimentation. The type and extent of sediment control measures 

employed and used would depend on the area disturbed, weather conditions, and the potential for 

sediment to be delivered to surface drainages using Best Management Practices (BMPs) and 

following the reclamation plan (see Appendix F, Reclamation Plan). Areas of particular 

emphasis with regard to potential erosion and sedimentation would be those sites where roads, 

utility corridors, and other project related activities cross or disturb drainage areas. 

All action alternatives and even with the implementation of BMPs would produce erosion rates 

above background conditions in the uplands (hillslopes above the stream channels). Intense 

rainfall (which implies heavy runoff) would increase the potential for sediment loading during 

severe thunderstorms common in the project area. The reduction of infiltration and concentration 

of flows from roads and pads would result in localized erosion and deposition, especially during 

the construction phase. For the most part, this sediment would be stored in the uplands and in 

ephemeral channels, but a portion would be transported to Seminoe Reservoir during storm 

events. However, a portion of this sediment would make it into surface waters under all action 

alternatives. The amount of this sediment would depend largely on the effectiveness of the 

erosion control practices. 

4­26  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

If accidental spills of project related materials were to occur, impacts to surface water would be 

common to all alternatives. Surface water quality impacts from spills could occur as a result of an 

accident during transportation, storage or use of site materials, such as diesel fuel. See also 

Section 4.12, Transportation, and Section 4.15, Accidents and Spills. 

4.4.3 Effects of Alternative B (Proposed Action)

Alternative B contemplates a phased implementation of 17 individual produced water discharge 

points emptying into 13 ephemeral drainages, one intermittent drainage, and three playa basins. 

See Figure 12, Produced Water Discharge Points – Alternative B. 

Table 4.4-2, Summary of Potential Discharge Locations, summarizes the proposed discharge 

site information. With data collected from Pool Table Draw, an estimated seven percent of the 

produced water discharged into the ephemeral and intermittent drainages would be lost to 

infiltration and evaporation before entering the North Platte River and Seminoe Reservoir, while 

the produced water discharged to the playa basins would temporarily pool before infiltrating back 

into the ground or evaporating. 

Table 4.4-2, Summary of Potential Discharge Locations 

Discharge 

Point (1) Watershed Drainage Type 

Number of 

Production 

Wells 

Feeding 

Discharge 

Estimated 

Average 

Discharge 

(cfs) 

Estimated 

Maximum 

Discharge 

(cfs) 

Estimated 

Avg Volume 

Reaching 

North Platte 

River 

System (cfs) 

Estimated 

Max Volume 

Reaching 

North Platte 

River 

System (cfs) 

DS-02 W. Fork Pool 

Table Draw Ephemeral 31 0.2 1.1 0.12 0.75 

DS-03 E. Fork Pool 

Table Draw Ephemeral 72 0.4 2.4 0.36 2.24 

DS-04 Ayers Draw Ephemeral 88 0.5 2.3 0.45 2.25 

DS-05 Dry Ditch Ephemeral 146 0.8 2.7 0.73 2.59 

DS-06 

Upper 

Dirtyman 

Draw 

Ephemeral 74 0.4 2.6 0.35 2.04 

DS-07 

Lower 

Dirtyman 

Draw 

Ephemeral 67 0.4 3.2 0.36 2.78 

DS-08 Longhart 

Draw Ephemeral 76 0.4 1.9 0.35 1.68 

DS-09 Unnamed 

Drainage #2 Ephemeral 50 0.3 1.5 0.24 1.40 

DS-10 

Upper West 

Fork Pool 

Table Draw 

Ephemeral 61 0.4 3.2 0.31 2.37 

DS-11 O'Brien Crk. Intermittent 45 0.4 1.8 0.31 1.49 

DS-12 Unnamed 

Drainage #1 Ephemeral 72 0.3 1.7 0.28 1.62 

Seminoe Road Gas Development Project 4­27
Draft Environmental Impact Statement November 2005

DS-13 Mountain 

Lion Draw Ephemeral 26 0.2 1.4 0.20 1.40 

DS-14 St. Mary’s 

Ditch Ephemeral 92 0.4 3.1 0.40 3.00 

DS-18 Unnamed 

Drainage #3 Ephemeral 43 0.2 1.5 0.20 1.42 

Notes: 

1. Flows from Pilot Project DS-1 would be re-routed to DS-2 for the full development phase of the Seminoe Road 

Project. 

Produced water is expected to be of similar quality to Pilot Project produced water for the 

proposed full project “build-out” and is expected to meet primary and secondary drinking and 

livestock standards. 

4.4.3.1 Effects to Ephemeral Drainages Within the EIS Analysis Area

Ephemeral drainage channels would likely adjust vertically and laterally in response to continuous 

water discharges from the Seminoe Road Project and storm events would accelerate or 

compound these effects. The extent of the erosion in ephemeral drainages would vary depending 

on the produced water flow volume, the drainage channel gradient and morphology, geology, and 

vegetative cover. However, in ephemeral drainages below where produced water is discharged, 

erosion can be expected to be above undisturbed conditions and would lead to increases in 

sediment loads into Seminoe Reservoir beyond background conditions. 

Based on experience from the Pilot Project, sections of ephemeral drainages would be expected 

to sustain substantial erosion (channel headcutting and bank erosion) downstream of where 

produced water is discharged. Pool Table Draw was listed as minor for erosion potential and yet 

experienced substantial erosion in portions of the channels, especially near the confluence with 

O’Brien Creek. The rest of the proposed drainages have a moderate to high rating for erosion 

potential, and are expected to have substantial erosion in portions of the drainage under this 

alternative. See Table 4.4-3, Erosion Potential of Proposed Discharge Drainages. 

As described earlier, produced water flowing continuously in ephemeral drainages would cause 

channels to form in areas with broad swells (low gradient drainage bottoms with no defined 

channel, typically moist with good grass production) and cause channels to adjust vertically and 

laterally. Due to these impacts to ephemeral channels, allotments may fail standards and guides 

assessments in the future, since forage production would be reduced in the channel bottoms 

(Standard 1) and riparian vegetation in channels bottoms would be less able to withstand storm 

events due to increased erosion (Standard 2) (BLM 1997). These impacts are expected even with 

4­28  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Table 4.4-3, Erosion Potential of Proposed Discharge Drainages 

Drainage Drainage Type Erosion Potential (1) 

Pool Table Draw Ephemeral Minor 

Ayers Draw Ephemeral Moderate 

Dry Ditch Ephemeral Moderate 

Dirtyman Draw Ephemeral High 

Longhart Draw Ephemeral Moderate 

Unnamed Drainage #2 Ephemeral Moderate 

O'Brien Creek Intermittent Minor 

Unnamed Drainage #1 Ephemeral Moderate 

Mountain Lion Draw Ephemeral High 

St. Mary’s Ditch Ephemeral Moderate to High 

Unnamed Drainage #3 Ephemeral Moderate to High 

Notes: 

1. Erosion potential based on observations made during the baseline drainage 

surveys (HydroGeo 2001, 2003a, and 2003b). Location of drainages shown 

on Figure 37, Watershed Map. 

the intensive management of ephemeral drainages; however, they would be reduced somewhat 

through intensive management in drainage channels. 

Standards 1 and 2 for healthy rangelands are (BLM 1997): 

� Standard 1 – Watershed Health: Within the potential of the ecological site (soil type, 

landform, climate, and geology), soils are stable and allow for water infiltration to provide 

for optimal plant growth and minimal surface runoff. 

� Standard 2 – Riparian/Wetland Health: Riparian and wetland vegetation have structural, 

age, and species diversity characteristic of the state of channel succession and is resilient 

and cable of recovering from natural and human disturbance in order to provide forage 

and cover, capture sediment, dissipate energy, and provide for ground water recharge. 

Ephemeral channel sediments, over and through which produced water would flow, would 

influence the quality of the produced water. Similar to the current situation in Pool Table Draw, 

downstream of where Pilot Project produced water is being discharged, it is expected that 

produced water flowing in ephemeral drainages would experience concentration increases in pH 

(5 to 10%), TDS (15 to 20%), iron (200 to 400%) and conductivity (15 to 20%), but sustain a 10 to 

15% reduction in SAR values. 

4.4.3.2 Effects From Intensive Erosion Management of Ephemeral Drainage

Channels

The Pilot Project has shown that continuous discharge of water into ephemeral channels results in 

channel incision and lateral adjustment producing channel erosion substantially above 

Seminoe Road Gas Development Project 4­29
Draft Environmental Impact Statement November 2005

undisturbed conditions. Although intense erosion management in ephemeral drainge channels 

has not been proposed by the Proponent, the BLM feels that such action would be necessary as a 

mitigation measure to reduce the energy of discharged water by increasing channel length and 

controlling vertical drops in the channel. This would be done with engineered channels, armoring 

small vertical drops fabric and rock, and building large vertical drop structures using Gabion 

basket structures (metal wire reinforced baskets for rock aggregate), large rock placements, 

sheet piling, and/or concrete weirs. These intensive erosion management actions would occur 

before surface discharge of project water begins to reduce in channel erosion from project 

actions. Under this alternative, detailed water management plans would be prepared for each 

phase of the development, techniques would be designed for each drainage channel impacted, 

and structures and/or engineered channels described above would be placed using heavy 

equipment before surface water discharges. 

Large vertical drop structures would be placed in areas with greater than 3 feet vertical incision 

and would need to be anchored into stable soils in the sides of drainages. According to the 

drainage survey, there would be about 20 large vertical drop structures. These drop structures as 

mentioned above can be built using sheet piling (interlocking corrugated sheet metal), large rock 

placements, rock Gabions, and/or concrete. These structures require heavy equipment and would 

need the construction of temporary roads to access construction sites and haul material. 

Engineered channels would require the disturbance of vegetation within drainages using heavy 

equipment, would require revegetation efforts, and could be subject to long term maintenance 

needs especially after storm events. Smaller structures would require temporary haul roads to 

place rip-rap (angular rock) and other materials, and would also require maintenance. 

Experience from the Pilot Project indicates that to intensively manage Pool Table Draw (listed as 

having minor erosion potential during baseline surveys) to handle current volumes of water (less 

than 1.5 cfs) without severe erosion or deposition would require at least one major drop structure, 

at least five small armoring structures for nick points. Additional well sites planned in the proposed 

action would use Pool Table Draw for water disposal and could result in at least 5.4 cfs of water 

discharge in the next few years and would require about three large structures. This additional 

discharge could require different efforts to intensively manage the Pool Table Draw. The water 

management plan for the first phase of the project build-out would include the design of the 

structures needed. Assuming these estimates are accurate, at least three temporary construction 

roads would need to be built, and maybe five additional haul roads. This would be in addition to 

4­30  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

the rest of the project disturbance needed to access and produce well sites in the watershed for 

Pool Table Draw. 

The design of effective, stable, naturally regulating, open channels that are not subject to severe 

erosion and/or deposition is a very difficult engineering problem. Even with the proper design of inchannel structures, the variability of natural conditions such as severe storm events, local 

conditions such as soil types, would require active management of these structures over the life of 

the project. A substantial reclamation effort at the end of the project would also be needed to 

redesign the structures for natural precipitation regimes. Also, unless the entire channel is treated, 

there would most likely be substantial erosion and deposition even with these efforts due to 

natural channel adjustment to project induced flows. 

Intensively managing these ephemeral systems (all additional channels were rated as moderate 

to high for erosion potential) would require a tremendous planning effort (at least 20 large 

structures and maybe 100 smaller grade control structures), construction with heavy equipment in 

channel bottoms, construction of temporary roads, hauling material for construction, revegetation 

efforts, long-term intensive management, and extensive reclamation efforts. New structures 

beyond original plans could be anticipated and secondary impacts from surface disturbance could 

be substantial. All of these efforts would be difficult to anticipate and would most likely not reduce 

overall channel erosion below undisturbed conditions. 

4.4.3.3 Effects to Intermittent Drainages Within the EIS Analysis Area

Sections of O’Brien Creek, the only intermittent drainage within the EIS analysis area, would be 

expected to sustain minor erosion (channel headcutting and side cutting) downstream of where 

produced water is discharged. See Table 4.5-3, Erosion Potential of Proposed Discharge 

Drainages. Similar to the effects expected for ephemeral drainages, the extent of the erosion in 

O’Brien Creek would vary depending on the produced water flow volume and the drainage 

channel gradient, morphology, geology and vegetative cover. 

O’Brien Creek water quality, including conductivity (salinity), is very similar to the water quality to 

be produced from the Seminoe Road Project coalbed natural gas wells (HydroGeo 2003a). As a 

result, no negative water quality impacts are expected from produced water being discharged into 

O’Brien Creek. 

Seminoe Road Gas Development Project 4­31
Draft Environmental Impact Statement November 2005

4.4.3.4 Effects to Playas Within the EIS Analysis Area

Under Alternative B, approximately one-fourth of the produced water (25,000 acre feet of water for 

the 30 year project life) would be discharged from discharge points DS-15, DS-16 and DS-17, and 

routed into three closed playa basins: Ferris Lake, Alkali Flats and St. Mary’s Anticline. See 

Figure 12, Produced Water Discharge Points – Alternative B. 

Playas within the EIS analysis area are typically dry but periodically flood in the spring with winter 

snowmelt and following periods of high precipitation. The estimated amount and volume of 

coalbed natural gas produced water to be discharged annually into the three EIS analysis area 

playas are set forth in Table 4.4-4, Estimates of Produced Water Discharge into Playas. 

Discharge to these playas (which are closed basins) would begin in year 4 or 5 and conclude at 

the end of project operations. 

Table 4.4-4, Estimates of Produced Water Discharge Into Playas 

Discharge Point DS-15 DS-16 DS-1 

Playa Ferris Lake Alkali Flats St. Mary’s Anticline Flats 

Area of Closed Basin Watershed (acres) 4,491 12,094 11,002 

Number of Coalbed Natural Gas Wells Feeding Discharge 67 181 47 

Estimated Average Discharge (cfs) 0.4 0.9 0.3 

Estimated Average Annual Discharge to Playa (acre-feet) 290 652 217 

Estimated Maximum Discharge (cfs) 1.8 5.0 2.3 

Estimated Maximum Annual Discharge to Playa (acre-feet) 1,303 3,620 1,665 

Estimated natural Inundated Area (acres) 20 - 25 50 - 60 10 - 50 

Maximum Inundated Area With Project Discharges (acres) 100 – 150 350 - 400 100 - 150 

Any water discharged into playa lakes in the closed basins would be subject to both infiltration and 

evaporation. Infiltration in the playas would be estimated to range from 10 to 20%. The annual 

evaporation for this part of south central Wyoming is estimated to be approximately 36 inches (3 

feet). Monthly evaporation is lowest during the winter and highest during the summer. 

During project operations, produced water is expected to pool in the three playas. The water 

levels would vary throughout the life of the project, depending on the amount of water discharged. 

Typically, because of varying evaporation rates throughout the year, playa lakes would cover the 

greatest area during the late winter and spring, then shrink in size during the summer. 

The barren lake bottom of the Ferris Lake playa covers an area of approximately 20 to 25 acres in 

size. During the years of maximum produced water discharge from discharge point DS-15 (years 

5 to 8), water in the Ferris Lake playa would expand to approximately 100 to 150 acres during the 

spring of that year (with a maximum depth of approximately 2 to 3 feet). During the summer 

4­32 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

months, with high evaporation rates, this playa lake would shrink to about 40 to 50 acres. During 

other years of the project, the water levels in the Ferris Lake would be less than the maximum 

pumping rate years. 

The Alkali Flats playa covers a broad area of approximately 1,000 acres, with a barren lake 

bottom zone of approximately 50 to 60 acres in size. During the years of maximum produced 

water discharge from discharge point DS-16 (years 6 to 9), water in the Alkali Flats playa would 

expand to approximately 350 to 400 acres during the spring of that year (with a maximum depth of 

approximately 4 to 5 feet). During the summer months, with high evaporation rates, this playa lake 

would shrink to about 100 to 150 acres. During other years of the project, the water levels in the 

Alkali Flats playa would be less than the maximum pumping rate years. 

The barren lake bottom of St. Mary’s Anticline Flats playa lake covers an area of approximately 10 

acres in size. During the years of maximum produced water discharge from discharge point DS17 (years 6 to 9), water in the St. Mary’s Anticline Flats Lake playa would expand to approximately 

100 to 150 acres during the spring of that year (with a maximum depth of approximately 2 to 3 

feet). During the summer months, with high evaporation rates, this playa lake would shrink to 

about 40 to 50 acres. During other years of the project, the water levels in the St. Mary’s Anticline 

Flats playa lake would be less than the maximum pumping rate year. 

Proposed water discharges into these playas would inundate areas greater than their maximum 

natural extent. The inundated vegetation in the areas outside the current lake beds would be 

replaced by salt and water tolerant plants. Since the inundated area is expected to change 

seasonally and over the life of the project, at times the vegetation may not meet Standard 3 for 

rangeland management (BLM 1997). 

Water that currently collects in playa lakes as well as project produced water would be affected by 

evaporation and chemical interaction with the poor quality playa soils. As a result, the playa lake 

water quality would be expected to have higher concentrations of trace constituents and salinity 

than produced water. 

4.4.3.5 Effects to North Platte River Upstream of Seminoe Reservoir

There would be very small flow increases to the North Platte River upstream of Seminoe 

Reservoir as a result of produced water discharge into Dirtyman Draw (DS-6 and DS-7) and 

Unnamed Drainage #3 (DS-18). See Figure 12, Produced Water Discharge Points – 

Seminoe Road Gas Development Project 4­33
Draft Environmental Impact Statement November 2005

Alternative B. An estimated 0.9 cfs from Dirtyman Draw (DS-6 and DS-7) and 0.9 cfs from 

Unnamed Drainage #3 (DS-18) would empty into the North Platte River upstream of Seminoe 

Reservoir. These flows combined would represent less than one percent of the average historic 

monthly flows in the North Platte River in this area. Historical flows in the North Platte have ranged 

from 300 to 4,100 cfs as measured at USGS gauging station #0663000. 

Likewise, there would be no adverse water quality effects to the North Platte River upstream of 

the Seminoe Reservoir as a result of produced water discharge. With the exception of conductivity 

(a measure of salinity), the water quality of produced water and the North Platte River are similar. 

Although the produced water has a higher average conductivity (1,580 μmhos/cm) than water in 

the North Platte River (historic range of 140 to 720 μmhos/cm), the disproportionate mixture of the 

two water volumes would result in negligible water quality changes to the North Platte River. For 

example, during the low flow period (October through March) of project year 7, (which is the 

estimated year of maximum project pumping), the mixing model (see Appendix J, Overview of 

Surface Water Mixing Model) predicts that salinity in the North Platte River above Seminoe 

Reservoir could increase approximately 3% (HydroGeo 2004b). The modeling effort reveals that 

this calculated maximum salinity would be well within the natural variation of the water quality 

within the river. Therefore, the discharge of produced water into the North Platte River above 

Seminoe Reservoir would not affect beneficial uses of the water. 

4.4.3.6 Effects to Seminoe Reservoir

An estimated daily average of 10 to 11 acre-feet of produced water would empty into the Seminoe 

Reservoir during project operations contemplated under Alternative B. During project year 7, 

pumping would peak such that a maximum daily rate of around 35 acre-feet of produced water 

would be discharged into the Seminoe Reservoir. See Figure 41, Project Water Production 

Schedule. These daily volumes are negligible when compared to the capacity of the Seminoe 

Reservoir, which has the potential to contain an estimated 1,017,000 acre-feet. 

Even given the recent low water levels in Seminoe Reservoir, which have ranged between 

approximately 435,000 and 770,000 acre-feet over the past few years, the maximum yearly 

volume of produced water (12,800 acre-feet) predicted to enter the Seminoe Reservoir in year 7 

of the project only represents 3% of the above low volume. On average, the project would 

discharge 3,600 to 4,100 acre feet of water per year into the reservoir; these volumes represent 

less than 1% of the reservoir’s total capacity. 

4­34 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

In the year 2000, an estimated 62,800 acre-feet of water evaporated from the Seminoe Reservoir 

(USDI Bureau of Reclamation 2000). The projected average monthly discharge of around 330 

acre feet of produced water into the Seminoe Reservoir would be much less than the monthly 

evaporation off the reservoir, which ranged from 1,100 acre feet in February to 11,100 acre feet in 

July (USDI Bureau of Reclamation 2000). 

With the exception of conductivity (a measure of salinity), the water quality of produced water and 

the North Platte River are similar. Although the produced water has a higher average conductivity 

(1,580 μmhos/cm) than water in the Seminoe Reservoir, which ranges from around 500 to 600 

μmhos/cm near the Seminoe dam, the disproportionate mixture of the two water volumes would 

result in negligible salinity changes in the Seminoe Reservoir. During project year 7 (which is year 

of maximum project pumping), the mixing model (see Appendix J, Overview of Surface Water 

Mixing Model) predicts that salinity in the Seminoe Reservoir could increase approximately 3%. 

For example, a natural conductivity of 600 μmhos/cm could potential increase to 620 μmhos/cm. 

Reservoir arms that lack mixing from tributary inputs and could have locally higher increases in 

salinity; however, these amounts would still be less than what would likely impact beneficial uses 

such as trout fisheries (See Section 4.7.2.13, Fisheries). Acute WET tests described in the 

impacts for Alternative A show the produced water is not toxic to common aquatic organisms 

(Fathead Minnows and Daphnia Magna). 

4.4.3.7 Effects to “Miracle Mile”

Produced water discharge would not affect flows in the stretch of the North Platte River known as 

the “Miracle Mile.” The federal government has mandated that discharge from Kortes Reservoir, 

which is located immediately downstream of Seminoe Reservoir, must maintain a discharge rate 

of 500 cfs into the Miracle Mile. 

Likewise, there would be no adverse water quality effects to the Miracle Mile as a result of 

produced water discharge. With the exception of conductivity (a measure of salinity), the water 

quality of produced water and the Miracle Mile are very similar. Although the produced water has a 

higher average conductivity (1,580 μmhos/cm) than water in the Miracle Mile (historic range of 

300 to 660 μmhos/cm as measured at USGS gauging station 06636000), the disproportionate 

mixture of the two water volumes would result in negligible water quality changes to the North 

Platte River. During the low flow period (October through March) of project year 7 (which is year of 

Seminoe Road Gas Development Project 4­35
Draft Environmental Impact Statement November 2005

maximum project pumping), the mixing model (see Appendix J, Overview of Surface Water 

Mixing Model) predicts that salinity in the North Platte River above Seminoe Reservoir could 

increase approximately 3%. For example, a natural conductivity of 600 μmhos/cm could 

potentially increase to 620 μmhos/cm. The modeling effort reveals that this calculated maximum 

salinity would be within the natural variation of the water quality within the river and the discharge 

of Project produced water is not expected to affect beneficial uses of the Miracle Mile water, 

particularly the blue ribbon trout fishery (see Section 4.7.2.13, Fisheries). 

4.4.3.8 Effects to North Platte River Downstream of Pathfinder Reservoir

There would be no adverse water quality effects to the North Platte River downstream of 

Pathfinder Reservoir as a result of produced water discharge. 

The theoretical annual average TDS load to the North Platte System from the Seminoe Road 

Project was calculated to be about 7,000 tons per year. To put this number in context, the TDS 

load from the North Platte River above Seminoe Reservoir is about 250,000 tons per year. 

4.4.4 Effects of Alternative C (Pipeline to Reservoir)

Under Alternative C, produced water would be piped and directly discharged into either the 

Seminoe Reservoir or a stretch of the North Platte River just upstream of Seminoe Reservoir. See 

Figure 14, Direct Discharge into Seminoe Reservoir – Alternative C. 

Produced water from the proposed full project “build-out” would meet primary and secondary 

drinking and livestock standards, and is expected to be of similar quality to Pilot Project produced 

water. As discussed in Section 4.5.1, Effects of Alternative A – No Action, Pilot Project produced 

water has met conditions and water quality standards imposed by the WDEQ NPDES permit. The 

watersheds and playas within the EIS analysis area would not be subjected to produced water 

discharge. 

This alternative would result in surface disturbance and potential increased sedimentation in 

drainages where reservoirs are constructed to store and cool project produced water before it is 

piped directly to perennial waters in the North Platte River and Seminoe Reservoir. Surface 

disturbance from construction of pipeline corridors and ancillary facilities could also result in some 

increase of sedimentation to drainages. However, BMP’s to control erosion and sedimentation 

would be implemented to mitigate and minimize adverse affects. These reservoirs would have a 

4­36  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

similar design to the stock pond in Pool Table Draw (see Figure 15, Design Concepts for Direct 

Discharge – Alternative C). 

There would be negligible flow increases to the North Platte River upstream of Seminoe 

Reservoir, and these would be the same as described for Alternative B. Likewise, under 

Alternative C, no adverse water quality effects are expected to the Seminoe Reservoir and the 

North Platte River, both upstream and downstream (Miracle Mile) of the reservoir. There is 

expected to be a slight increase in conductivity in the Miracle Mile, but would not effect the 

beneficial uses of this blue ribbon trout fishery. Salt loading is expected to be similar as those 

described in Alternative B, about 3% per year during maximum discharges of produced water. 

Surface water quality effects would be similar to those for Alternative B. See Section 4.5.3, Effects 

to Alternative B (Proposed Action). 

4.4.5 Effects of Alternative D (Underground Injection)

Under Alternative D, produced water would be routed to collection points then injected 

underground into the Dad Sandstone. See Figure 16, Underground Injection of Produced 

Water – Alternative D. 

With underground injection of produced water, there would be no effects to the flows and water 

quality in the North Platte River system. The entire estimated 101,000 acre feet of produced water 

would be re-injected underground and not available to downstream flows. The drainages and 

playas within the EIS analysis area would not be subjected to produced water discharge. 

4.4.6 Indirect Effects

Potential impacts could result from off-site spills or releases, but the potential for such impacts are 

low. See also Section 4.12, Transportation, and Section 4.15, Accidents and Spills. 

4.4.7 Cumulative Impacts

Downstream demands for water in the Platte River drainage would continue to influence the 

operations of North Platte River reservoirs, and water levels in these reservoirs (particularly in 

Seminoe Reservoir) are expected to fluctuate into the future. In addition, regional surface water 

quality would continue to be influenced by local and regional land use trends and activities, which 

include ranching and farming, oil and gas exploration and development, coal mining (albeit 

reduced from historic levels), and recreational use. 

Seminoe Road Gas Development Project 4­37
Draft Environmental Impact Statement November 2005

Because regional coal mining activities are greatly reduced from historic levels and given the strict 

federal and state governmental drainage and sediment control measures, there would be no 

measurable surface water cumulative effects as a result of coal mining activities in the region. 

There are some coal mining activities that are currently under the process of reclamation on the 

east side of Seminoe Reservoir, and this reclamation work is not expected to impact surface 

waters. 

Ranch management and grazing activities within and adjacent to the EIS analysis area would be 

required to meet standards for rangeland management on public lands (BLM 1997), and therefore 

are not expected to have measurable effects to surface water resources. Since livestock tend to 

concentrate around stock ponds and in drainage areas in search of water, there would be 

localized effects to surface waters, which could lead to greater erosion where surface disturbance 

occurs and livestock concentration areas coincide. 

Irrigation activities and municipal water systems above and below the EIS analysis area would 

contribute additional salt loading into the North Platte System. The total annual average TDS load 

to Seminoe Reservoir from the Seminoe Road Project was calculated to be a maximum of 7,000 

tons per year. The existing TDS load from the North Platte into Seminoe reservoir is about 

250,000 tons per year. 

Recreational activities like boating, fishing, swimming, hunting and camping would have minimal 

additional effects on surface water. Off-road travel in drainage areas could locally cause effects to 

surface waters, but these effects would be limited in the EIS analysis area given restricted travel 

through the checkerboard federal and private ownership. 

Additional oil and gas exploration and development could potentially occur in the areas within and 

surrounding the EIS analysis area. Another coalbed natural gas pilot project development, known 

as the Hanna Draw Project, is being considered for an area approximately 20 miles east of the 

EIS analysis area. The proponent for this Hanna Draw Project is currently assessing the possibility 

of discharging produced water into the Medicine Bow River, which flows into Seminoe Reservoir. 

This project is in the exploratory stage, but could potentially produce as much water as the 

Seminoe Project. The conditions of the future discharge and the potential water quality are 

uncertain. The most likely cumulative effect if this project is developed would be salt loading to the 

North Platte River system. 

4­38  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

4.4.8 Potential Monitoring and Mitigation

As explained in Section 2.4, Alternative B – Proposed Action, the Seminoe Road Project would be 

developed in a phased approach. Individual NEPA analyses and water management plans would 

be prepared for each new build-out phase of the Seminoe Road Project. Specific monitoring and 

mitigation requirements would also be developed for each project phase. As part of the first 

development phase of the project, it is recommended that the Proponent complete or obtain the 

following information and data: 

� Monitor water quality of the North Platte River above Seminoe Reservoir, Seminoe 

Reservoir, and in the Miracle Mile stretch of the North Platte River. This data would be 

used to assess potential effects from produced water discharge into the North Platte River 

drainage. This would include routine water quality monitoring of existing sites on the North 

Platte River above Seminoe Reservoir like the Dugway Recreational area, sites on 

Seminoe Reservoir (near the mouth of O’Brien Creek), and monitoring at the current 

USGS gauging station on the Miracle Mile. 

� If Alternative B is selected, analyze hydraulic characteristics of ephemeral and intermittent 

drainages prior to any produced water discharge into drainages and include structure 

designs in the water management plan for each project phase. This analysis would 

assess the capacity of the drainage to handle projected flows without causing excessive 

erosion, and would involve establishing pre-discharge drainage cross-sections and 

monitoring these areas during operations. 

� If Alternative B is selected, develop drainage-specific erosion mitigation plans to address 

potential erosional problem areas prior to produced water discharge. Such plans could 

include targeted grade control structures, check dams, impact basins, channel 

reconstruction, or other possible engineered erosion control measures. Any structures 

would be inspected once in the spring and once in the fall. 

� If Alternative B is selected, complete a site-specific water balance for any produced water 

released into the three playas. This assessment would address the expected aerial 

coverage of produced water in these playas by season and by year. The information 

would be used to ensure that access roads, well pad sites or any sensitive environmental 

sites (e.g., sage grouse leks, raptor nests, cultural sites, etc.) are not inundated by 

produced water accumulating in the playas. 

Seminoe Road Gas Development Project 4­39
Draft Environmental Impact Statement November 2005

4.5 Ground Water

Ground Water Impact Significance Criteria: Ground water impacts would be considered 

significant if: 

� Ground water depletions cause measurable effects to ground water wells; 

� Ground water depletions cause measurable effects to surface water flow in the North 

Platte River downstream of Seminoe Reservoir; and, 

� Ground water quality is degraded in any freshwater aquifer. 

The desorption (release) of coalbed natural gas occurs when the ground water pressure (hydrostatic 

pressure) in coal formation is reduced by pumping water out of the formation via a well. As hydrostatic 

pressure drops, the physical bond between the coal and the entrained natural gas breaks, and the 

gas diffuses through the coal into the production well. Therefore, to create favorable conditions for the 

release of natural gas from coal seams, ground water must be pumped from the coal seam prior to 

and during natural gas extraction. Studies conducted in conjunction with coalbed natural gas 

production in Wyoming’s Powder River Basin have shown that up to 20% of the entrained water must 

be removed in order to depressure the coal sufficiently to facilitate gas desorption (HydroGeo 2004b). 

It is important to note that the gas producing coal seams are often confined, and the ground water in 

these formations is naturally under high pressure. Simply put, this means that a well installed in a 

confined coalbed may have a ground water level far above the actual top of the coalbed and in many 

cases thousands of feet above the top of the coal. A reduction in ground water pressure does not 

mean the coalbed would be dewatered, only that the hydrostatic pressure would be reduced. 

The drop in hydrostatic pressure due to well pumping also creates ground water drawdown. 

Drawdown is typically the greatest at the pumping well and declines with distance from the well, 

resulting in a drawdown cone (or cone of depression) around the pumped well. 

4.5.1 Overview of Ground Water Model

A regional scale three-dimensional ground water flow model was prepared for the Seminoe Road 

Project (Seminoe Road Ground Water Model). Regional ground water models provide a relative tool 

to simulate very complex large scale natural systems and are used regularly in EIS analyses to help 

evaluate the effects of various action alternatives and the cumulative effects from other activities. 

4­40  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

These types of models generate numerical results; however, the results only show the general 

character of the effects of the modeled action alternative as opposed to the actual size or magnitude 

of the effects. The Seminoe Road Ground Water Model was used to simulate and compare the short 

and long-term effects to the natural ground water system of Alternative B and C (ground water 

pumping and surface discharge of produced water) and Alternative D (pumping and re-injection of 

produced water). 

The Seminoe Road Ground Water Model was developed using the computer program MODFLOW. 

MODFLOW, which is a well used and acceptable model to analyze the potential effects of gas 

development projects on ground water resources. The Seminoe Road Ground Water Model is based 

on a conceptual model of the Hanna Basin hydrogeologic system derived from site specific and 

regional geologic and hydrogeologic information (HydroGeo 2003a). The model domain encompasses 

the entire Hanna Basin, an area of approximately 1,750 square miles, see Figure 31, Hanna Basin, 

and incorporates nine layers which represent the major geologic formations, listed from geologically 

youngest to oldest: Fern’s Formation, Hanna Formation, Medicine Bow Formation, Fox Hills 

Sandstone, Dad Sandstone, and Mesaverde Coal Bearing Formation (Almond Formation, Pine Ridge 

Sandstone, Allen Ridge Formation, and Haystack Formation). 

The boundaries of the model utilize natural hydrogeologic features such as major faults, anticlines, 

and surface water features. The bottom of the model is bound by the impermeable Steele Shale. The 

hydraulic input parameters (hydraulic conductivity, storage, specific yield) for the Seminoe Road 

Ground Water Model were derived from site-specific data and literature based information. A more 

detailed description of the numerical model used to analyze ground water impacts and the detailed 

modeling results are set forth in the August 2004 Draft Ground Water Modeling Technical Report 

(HydroGeo 2004a). 

4.5.2 Effects of Alternative A (No­Action)

Under Alternative A (no action), Pilot Project operations could continue under the terms and 

conditions of the 2001 BLM approval for this activity. There have been no measurable Pilot 

Project induced effects to ground water quality or ground water levels in water wells, spring flows 

or changes in ground water quality, or reduction of surface water flows or changes in water quality 

in the North Platte River. 

Seminoe Road Gas Development Project 4­41
Draft Environmental Impact Statement November 2005

Existing land use trends in the area would continue, and other oil and gas development and coal 

mining activities could cause localized impacts to ground water resources. It is not expected that 

ranch management activities (grazing) and recreation would have any effect on ground water 

resources in the area. 

4.5.2.1 Effect to Mesaverde Coal Bearing Formations (Lower Formation)

The Pilot Project pumping has not caused any measurable effects either to water levels or water 

quality in ground water wells installed in the Mesaverde strata in the area, although the pumping 

activity has removed ground water from the Mesaverde formations and has caused a localized 

reduction in ground water pressure in the coal-bearing formations and possibly adjacent 

formations within and immediately surrounding the Pilot Project area. Current data from the Pilot 

Project observation well (a pressure monitoring well located in the center of the Pilot Project well 

field) indicates that the ground water level in the Mesaverde formations has lowered about 1,000 

feet since the start of project ground water pumping in 2001 (Dudley 2005). The drawdown cone 

is localized, and Pilot Project pumping has not affected any of the area’s ground water resources 

used for other purposes. 

4.5.2.2 Effects to Medicine Bow/Fox Hills Coal Bearing Formation (Upper

Formation)

Pilot Project operations involve only pumping from Mesaverde formations, and there is no 

indication of any hydraulic connection between the Mesaverde and Medicine Bow strata. There 

have been no measurable effects to either water levels or water quality in ground water wells 

installed in the Medicine Bow/Fox Hills Sandstone formations resulting from Pilot Project pumping 

activities. 

4.5.2.3 Effects to Alluvial Ground Water Systems Within and Adjacent to EIS

Analysis Area

Surface discharge of produced water from the Pilot Project into Pool Table Draw has saturated 

the alluvium in the drainage creating a localized shallow ground water system. Prior to Pilot 

Project operations, Pool Table Draw was an ephemeral drainage that flowed only during 

precipitation and snow melt events. As a result of the discharge of Pilot Project produced water, 

the alluvium in the drainage has become saturated and riparian vegetation has developed in some 

areas. See Section 3.6.2.1, Pilot Project Produced Water Riparian Zones, and Section 4.6.1, 

Vegetation Effects of Alternative A (No Action). 

4­42 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Figure 38, Pool Table Draw Photographs, illustrates some of the effects of Pilot Project 

produced water on the drainage. The saturated soils in Pool Table Draw are also more prone to 

erosion from surface water flow than unsaturated soils and as a result have shown accelerated 

erosion such as headcutting and downcutting of the drainage channel. The BLM has installed 

several monitoring sites in Pool Table Draw to evaluate changes in channel configuration. See 

Appendix I, Monitoring Results for Seminoe Road Pilot Project. 

4.5.2.4 Effects to Springs Within and Adjacent to the EIS Analysis Area

There have been no measurable effects to either flows or water quality in area springs resulting 

from Pilot Project or other activities in the area. No additional effects to springs are anticipated at 

the current activity level. 

4.5.2.5 Effects to Stock Wells Within and Adjacent to the EIS Analysis Area

There have been no measurable effects to either water levels or water quality in area stock wells 

from Pilot Project or other activities in the area based on recent monitoring data. See Section 

3.4.5, Stock Wells Within and Adjacent to the EIS Analysis Area. No additional effects to stock 

wells are anticipated at the current activity level. 

4.5.2.6 Effects to Domestic Wells Within and Adjacent to the EIS Analysis Area

There have been no measurable effects to either water levels or water quality in area domestic 

wells from Pilot Project or other activities in the area based on recent monitoring data. See 

Section 3.4.6, Domestic Wells Within and Adjacent to the EIS Analysis Area. No additional effects 

to domestic wells are anticipated at the current activity level. 

4.5.3 Effects Common to All Action Alternatives

Under all action alternatives, the same amount of ground water would be pumped from the 

Mesaverde and Medicine Bow formations to liberate the natural gas entrapped in the target coal 

seams. The partial removal of ground water from the coal-bearing zones would affect ground 

water pressures and would lessen water availability within the target coal seams, as well as in the 

overlying and underlying water-bearing formations. No degradation of ground water quality would 

be expected as a result of pumping. 

Existing land use trends in the area would continue, and other oil and gas development and coal 

mining activities could cause localized impacts to ground water resources. It is not expected that 

Seminoe Road Gas Development Project 4­43
Draft Environmental Impact Statement November 2005

ranch management activities (grazing) and recreation would have any effect on ground water 

resources in the area. 

4.5.4 Effects of Alternative B (Proposed Action)

Under the Alternative B (Proposed Action), the Seminoe Road Project operations would develop 

and produce natural gas from the Mesaverde formation coals (Almond and Allen Ridge 

formations) and coalbeds in the Medicine Bow Formation. Ground water would be pumped from 

these formations to promote natural gas production and the project-produced water would be 

discharged to surface drainages. 

Under this alternative, ground water modeling (HydroGeo 2004a) indicates that the greatest 

drawdown within the EIS analysis area would occur during year 7 of project operations, when 

pumping is at its maximum. Following year 7, pumping rates and the resultant ground water 

drawdown would decrease until the end of the operations. The modeled ground water levels 

recovered to near their pre-pumping elevations within about a year of the end of the project 

(HydroGeo 2004b). Predicted temporary ground water depressurization (drawdown) and recovery 

during and post project operations is presented in Figure 43, Potential Ground Water 

Drawdown and Recovery (Alternatives B and C). 

Pumping of ground water is not expected to cause any measurable depletion to flows in the North 

Platte River system (HydroGeo 2004b). However, discharge of project-produced water would 

increase flows to the North Platte River system during the life of the project. It is predicted that 

ground water levels would return to pre-pumping levels within a year after project operations 

cease and long-term depletions of the North Platte River system waters are not anticipated 

(HydroGeo 2004b). 

A ground water sample from the Mesaverde formations from a Pilot Project well was age-dated to 

be over 5,000 years old. The antiquity of the water demonstrates that the Mesaverde ground 

water system is stagnant with little or no connectivity with shallow ground water-bearing zones or 

area surface water resources (BLM 2001). The ground water from the Medicine Bow Formation 

has not been age dated. 

Existing land use trends in the area would continue, and other oil and gas development and coal 

mining activities could cause localized impacts to ground water resources. It is not expected that 

4­44 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

ranch management activities (grazing) and recreation would have any effect on ground water 

resources in the area. 

4.5.4.1 Effects to Mesaverde Coal Bearing Formation (Lower Formation)

In the target coal zones in the Mesaverde formations (Almond and Allen Ridge formations), maximum 

modeled drawdown could potentially exceed 1,000 feet near the center of the EIS analysis area and 

could approach 2,000 feet on the west side project area near the Haystack Mountains in year 7. After 

year 7, ground water drawdown would decrease to less than 5 feet at the end of operations and return 

pre-pumping levels a year later. 

4.5.4.2 Effects to Medicine Bow/Fox Hills Coal Bearing Formation (Upper

Formation)

Modeled drawdown in the Medicine Bow Formation would be greatest in outcrop areas in the 

Haystack Mountains where drawdown could exceed 250 feet in year 7. After year 7, ground water 

drawdown would decrease to less than 5 feet at the end of operations and return to pre-pumping 

levels a year after cessation pumping. 

4.5.4.3 Effects to Alluvial Ground Water Systems Within and Adjacent to EIS

Analysis Area

Project-related ground water drawdown is not expected to affect any alluvial ground water 

systems. However, under Alternative B, produced water would infiltrate and saturate the alluvium 

material in the drainages below discharge points. See Figure 12, Produced Water Discharge 

Points - Alternative B. This would create an alluvial ground water system that did not exist 

previously. After discharge ceases, these localized alluvial ground water systems would dry up 

and return to pre-discharge conditions. This situation is happening in Pool Table Draw 

downstream of the Pilot Project produced water discharge points. See Section 4.4.2, No Action 

Alternative. Natural alluvial ground water systems along the North Platte River and other perennial 

streams in the area would not be affected by operations of the Seminoe Road Project. 

4.5.4.4 Effects to Springs Within and Adjacent to the EIS Analysis Area

The drawdown of ground water levels at the water table could affect spring flows within and 

adjacent to the EIS analysis area. However, because of the complex hydrogeology in the area, it 

is not possible to predict the quantitative effect of project-induced drawdown on area springs. The 

Seminoe Road Gas Development Project 4­45
Draft Environmental Impact Statement November 2005

potential flow changes at springs in the EIS analysis area are shown in Table 4.5-1, Potential 

Flow Reduction at Springs (Alternatives B and C). 

Based on the Seminoe Road Ground Water Model drawdown results, the potential reduction of 

spring flow or water level reduction in wells has been characterized as follows: 

� High - modeled drawdown greater than 500 feet; 

� Moderate - modeled drawdown between 200 to 500 feet; 

� Low - modeled drawdown less than 200 feet; and, 

� Negligible – modeled drawdown less than 10 feet. 

In all cases, after cessation of project pumping, potential reductions of water levels in alluvial wells 

would be negligible. 

Table 4.5-1, Potential Flow Reduction at Springs (Alternatives B and C) 

Monitored Site (1) Projected Producing Interval 

Potential Reduction of 

Spring Flow at Maximum 

Drawdown in Year 7 

Potential Spring Flow 

Reduction at the End 

of Operations 

O’Brien Spring Mesaverde sandstone bedrock fault High Negligible 

Corral Creek Spring Mesaverde shallow bedrock or alluvium Low Negligible 

Ayers Spring Medicine Bow shallow bedrock or alluvium Low Negligible 

Miller Bend Spring Mesaverde fractured bedrock Moderate Negligible 

Alkali Flat Spring #1 Medicine Bow shallow bedrock or alluvium Low Negligible 

Alkali Flat Spring #2 Medicine Bow shallow bedrock or alluvium Low Negligible 

St. Mary’s Spring Ferris Formation shallow bedrock fracture Low Negligible 

Note: 

1. Spring locations are shown on Figure 33, Hydrologic Monitoring Sites Location Map. 

Project operations are not expected to affect spring water quality. 

4.5.4.5 Effects to Stock Wells Within and Adjacent to the EIS Analysis Area

The drawdown of ground water levels could reduce water levels in stock wells within and adjacent 

to the EIS analysis area. The potential water level changes in EIS analysis area wells are shown 

in Table 4.5-2, Potential Water Level Reduction at Stock Wells (Alternatives B and C). 

Project operations are not expected to affect stock well water quality. 

4­46  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Table 4.5-2, Potential Water Level Reduction at Stock Wells (Alternatives B and C) 

Monitored Site (1) Projected Producing 

Interval 

Potential Reduction 

of Water Levels in 

Year 7 

Modeled Reduction of 

Water Levels at the End 

of Operations 

Section 19 Well Mesaverde High Negligible 

Miller # 1 Well Medicine Bow Moderate Negligible 

Little Shoe Well Mesaverde High Negligible 

Dry Ditch Well #1 Medicine Bow Low Negligible 

Dry Ditch Well #2 Medicine Bow Low Negligible 

Alkali Flat Well Mesaverde Low Negligible 

Note: 

1. Well locations are shown on Figure 33, Hydrologic Monitoring Sites Location Map 

4.5.4.6 Effects to Domestic Wells Within and adjacent to the EIS Analysis Area

The drawdown of ground water levels could affect reduce water levels in domestic wells within 

and adjacent to the EIS analysis area. The potential drawdown in EIS analysis area wells is shown 

in Table 4.5-3, Potential Water Level Reduction at Domestic Wells (Alternatives B and C). 

Table 4.5-3, Potential Water Level at Domestic Wells (Alternatives B and C) 

Monitored Site (1) Projected Producing 

Interval 

Potential Reduction 

of Water Levels in 

Year 7 

Modeled Reduction 

of Water Levels at the 

End of Operations 

ID Ranch Well Medicine Bow Moderate Negligible 

Boat Club Well 

Medicine Bow or 

Seminoe Reservoir 

Alluvium 

Low Negligible 

Sheller Well North Fork Alluvium Low Negligible 

Note: 

1. Well locations are shown on Figure 33, Hydrologic Monitoring Sites Location Map 

Project operations are not expected to affect domestic well water quality. 

4.5.5 Effects of Alternative C (Pipeline to Reservoir)

Under Alternative C, produced water would be routed directly to the Seminoe Reservoir and/or the 

North Platte River, and the volume of produced water and production timeframes would be the 

same as Alternative B. The effects on water resources in the bedrock aquifers would also be 

expected to be the same as Alternative B. Under Alternative C, alluvium in the discharge 

drainages would not receive recharge from surface infiltration of produced water, as produced 

water would be discharged directly into the Seminoe Reservoir and/or the North Platte River. See 

Figure 14, Direct Discharge into Seminoe Reservoir – Alternative C. 

Seminoe Road Gas Development Project 4­47
Draft Environmental Impact Statement November 2005

4.5.6 Effects of Alternative D (Underground Injection)

As discussed in detail in Section 2.6, Underground Injection of Produced Water Under Alternative 

D, produced water would be routed to centralized locations within the EIS analysis area and 

injected into the Dad Sandstone. See Figure 16, Underground Injection of Produced Water – 

Alternative D. The volume of produced water and production timeframes under Alternative D 

would be the same as for Alternatives B and C. 

Impermeable shale layers of the Lewis Shale Formation encapsulate the Dad Sandstone. As a 

result, it is assumed that the Dad Sandstone is saturated, and the water in this formation is 

probably under relatively high pressure, with limited groundwater movement into adjacent to 

impermeable shale strata. 

Given this situation, the Proponent may probably need to employ high-pressure injection, as well 

as hydro-fracturing techniques to increase the permeability of the Dad Sandstone. Hydrofracturing involves injecting a sand/water mixture under very high pressure through the injection 

well, borehole into the target formation, creating open fractures, thus increasing the formation 

permeability. Further, if the existing water within the Dad Sandstone is too highly pressurized, it 

may be necessary to increase the number of injection wells beyond those shown on Figure 16, 

Underground Injection of Produced Water – Alternative D. 

Injecting water into the Dad Sandstone would increase pressure in that formation, such that 

localized underground pressure mounds would be created around the injection wells. Because the 

Lewis Shale has very low permeability, it is not expected that re-injected produced water would 

migrate, or leak, into the surrounding shale strata. 

It is assumed that the water quality of the Dad Sandstone is similar to that of the Mesaverde 

Formation. If this is true, there should be no impact to the water quality of the Dad Sandstone with 

underground injection of produced water. 

Under Alternative D, the Seminoe Road Project ground water pumping is not expected to have 

any measurable effects on flows in the North Platte River system (HydroGeo 2004b). However, 

without surface discharge of project-produced water, there would be no increase flows to the 

North Platte River system for the life of the project as in Alternatives B and C. It is predicted that 

ground water levels would return to pre-pumping levels within a year after project operations 

4­48  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

cease, and no long-term depletions of the North Platte River system waters are anticipated 

(HydroGeo 2004b). 

4.5.6.1 Effect to Mesaverde Coal Bearing Formation (Lower Formation)

Same as Alternative B and C. 

4.5.6.2 Effects to Medicine Bow/Fox Hills Coal Bearing Formation (Upper

Formation)

Because the Dad Sandstone might have some hydraulic connectivity to the Medicine Bow 

Formation, re-injection of produced water into the Dad Sandstone could potentially offset some of 

the project induced drawdown in the Medicine Bow Formation. The Ground Water Modeling 

results indicate that there would be negligible drawdown in the Medicine Bow Formation, and, in 

some areas, ground water levels could actually increase, due to pressurized injection of produced 

water into the Dad Sandstone (HydroGeo 2004a). 

4.5.6.3 Effects to Alluvial Ground Water Systems Within and Adjacent to EIS

Analysis Area

Same as Alternative C. 

4.5.6.4 Effects to Springs Within and adjacent to the EIS Analysis Area

The drawdown of ground water levels could affect spring flows within and adjacent to the EIS 

analysis area. However, because of the complex hydrogeology in the area it is not possible to 

predict the actual effect of project-induced drawdown on area springs. The predicted drawdown 

would peak in Year 7, then decrease for the rest of the project life. See Table 4.5-4, Potential 

Flow Reduction at Springs (Alternative D). 

Table 4.5-4, Potential Flow Reduction at Springs (Alternative D) 

Monitored Site (1) Projected Producing Interval 

Potential Reduction of 

Spring Flow at Maximum 

Drawdown in Year 7 

Potential Spring Flow 

Reduction at end of 

Operations 

O’Brien Spring Mesaverde sandstone bedrock fault High Negligible 

Corral Creek Spring Mesaverde shallow bedrock or alluvium High Negligible 

Ayers Spring Medicine Bow shallow bedrock or alluvium None Negligible 

Miller Bend Spring Mesaverde fractured bedrock Moderate Negligible 

Alkali Flat Spring #1 Medicine Bow shallow bedrock or alluvium Low Negligible 

Alkali Flat Spring #2 Medicine Bow shallow bedrock or alluvium Negligible Negligible 

St. Mary’s Spring Ferris Formation shallow bedrock fracture Negligible Negligible 

Note: 

1. Well locations are shown on Figure 33, Hydrologic Monitoring Sites Location Map 

Seminoe Road Gas Development Project 4­49
Draft Environmental Impact Statement November 2005

4.5.6.5 Effects to Stock Wells Within and Adjacent to the EIS Analysis Area

The drawdown of ground water levels could reduce water levels in stock wells within and adjacent 

to the EIS analysis area. The predicted water level changes at wells in the EIS analysis area is 

shown in Table 4.5-5, Potential Water Level Reduction at Stock Wells (Alternatives D). 

Table 4.5-5, Potential Water Level Reduction at Stock Wells (Alternative D) 

Monitored Site (1) Projected Producing 

Interval 

Potential Reduction of Water 

Levels in Year 7 

Modeled Reduction of Water Levels 

at end of Operations 

Section 19 Well Mesaverde Negligible Negligible 

Miller # 1 Well Medicine Bow High Negligible 

Little Shoe Well Mesaverde Negligible Negligible 

Dry Ditch Well #1 Medicine Bow Low Negligible 

Dry Ditch #2 Medicine Bow Negligible Negligible 

Alkali Flat Well Mesaverde Low Negligible 

Note: 

1. Well locations are shown on Figure 33, Hydrologic Monitoring Sites Location Map 

4.5.6.6 Effects to Domestic Wells Within and Adjacent to the EIS Analysis Area

Same as Alternatives B and C. 

4.5.7 Indirect Effects

The potential for indirect ground water impacts to the region are expected to be minimal, because 

most employees live or would choose to live in communities with established water and sewer 

systems. If employees choose to live in rural areas, domestic water wells would probably be 

drilled; however, these wells should have little indirect effect on ground water quality or quantity. 

4.5.8 Cumulative Impacts

The primary activities that could affect ground water resources within and adjacent to the EIS analysis 

area include natural gas projects, coal mining, and pumping from local livestock and domestic wells. 

Pumping operations related to future coalbed natural gas projects like the proposed Hanna Basin 

Project (20 miles east of the EIS analysis area) could potentially amplify the ground water drawdown 

effects. The Hanna Formation coal zones are the production targets for the Hanna Basin Project. 

These coal horizons are stratigraphically much higher than the Mesaverde Group coal targeted by the 

Seminoe Road Project and are not believed to be hydraulically connected. However, the Medicine 

Bow coals targeted for the Seminoe Road Project are relatively close to the Hanna Formation and 

could potentially have some hydraulic connectivity. Pumping from both of these formations could 

increase ground water drawdown effects in areas where the cone of depressions of the two projects 

4­50  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

overlap. The timing and pumping rates for the Hanna Basin Project are not known, so overall 

cumulative hydrologic impacts are not possible to assess at this time. 

Coal mining operations within and surrounding the EIS analysis area have been curtailed in recent 

years, and much of the disturbed areas have been reclaimed. There are no known new coal mining 

projects planned in the future in this area. No cumulative effects due to coal mining is anticipated. 

Pumping of local livestock and domestic wells use comparatively little ground water; therefore no 

cumulative effects as a result of pumping these wells is expected. 

4.5.9 Potential Monitoring and Mitigation

As explained in Section 2.4, Alternative B, Proposed Action, the Seminoe Road Project would be 

developed in a phased approach. Individual EA and WMPs would be developed and updated for each 

new “build-out” phase of the Seminoe Road Project. Specific monitoring and mitigation requirements 

would also be developed for each phase of the Project. As part of the first development phase of the 

project, it is recommended the Proponent complete or obtain the following information and data: 

� Age dating of the ground water in the target coal zones of the Medicine Bow/Fox Hills 

formations to determine possible connectivity to the North Platte River system; 

� Hydrologic testing of the target coal zones Medicine Bow/Fox Hills formations to measure the 

hydraulic properties and allow better ground water characterization of these zones; 

� Install monitoring wells within the target coalbeds and adjacent formations in the proposed 

well field of each development phase to allow on-going assessment of water pressures and 

water quality conditions; 

� Monitoring of water levels in the new monitoring wells during and after operations to assess 

potential project induced ground water drawdown; 

� Monitoring of water levels and flows of major springs, stock wells, and domestic wells in the 

area as identified in the Baseline Monitoring Study (HydroGeo 2003a) to assess potential 

effects from project induced ground water drawdown; 

� If there is a reduction of flow to a developed springs or reduced water levels in wells, the 

Proponent would replace this water source with an acceptable alternative; 

� Ground water replacement alternatives could include: 

Seminoe Road Gas Development Project 4­51
Draft Environmental Impact Statement November 2005

•	 Replace a spring with a guzzler (a device that captures and stores rainfall); 

•	 Replace a spring with a water well; 

•	 Route project produced discharge water to the effected site or to an acceptable 

alternative site; 

•	 Replace a well with another well; and 

•	 Replace a domestic well with hauled water. 

� If produced water is to be re-injected into the Dad Sandstone, hydrologic testing of this 

sandstone unit would be necessary to measure hydraulic properties and allow better ground 

water characterization. 

4.6 Vegetation

Vegetation Impact Significance Criteria: Vegetation impacts would be considered significant if: 

� There was non-compliance with the Great Divide RMP; 

� Reclamation was not in compliance with Executive Order 13112 (Invasive Species); 

� Reclamation would not support the pre-existing land uses, including wildlife habitat; 

� The project violated the Clean Water Act, Executive Order 11988 (Floodplains), and 

Executive Order 11990 (Wetlands and Riparian Zones); 

� Weeds jeopardized reclamation efforts or post-project land use; or, 

� The project jeopardized the persistence of any BLM Wyoming state sensitive plant. 

Native vegetation plays an important role in controlling erosion, providing wildlife habitat and 

maintaining biological diversity. Disturbance to the vegetation resources can result in impacts to 

these ecosystem functions. 

Anticipated impacts to vegetation are directly related to the estimated acres of disturbance. 

Reclamation would eventually mitigate most impacts to vegetation. See Table 4.6-1, Vegetation 

Impact Acreage Estimates. 

4­52 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Table 4.6-1, Vegetation Impact Acreage Estimates 

Vegetation Community2 Total Area3 

(acres) 

Reclamation 

Potential

4 

Alternatives B & D5 

(acres) 

Alternative C5 

(acres) 

Wyoming Sagebrush/Mixed Grass 29,320 M 1,465 / 554 1,520 / 594 

Wyoming Sagebrush/Threadleaf 

Sedge 

29,230 M 1,469 / 558 1,499 / 581 

Wyoming Sagebrush/Green 

Rabbitbrush 

1,910 M 63 / 23 63 / 23 

Low Shrub/Mixed Grass 34,010 L/M 1,727 / 664 1,817 / 729 

Mixed Sagebrush 3,250 L/M 120 / 44 120 / 44 

Mixed Shrub 12,180 L/M 421 / 155 423 / 156 

Mixed Grass 3,120 M 182 / 67 182 / 67 

Threadleaf Sedge/Mixed Grass 1,260 M 63 / 23 65 / 23 

Basin Big Sagebrush/Greasewood 1,970 L/M 63 / 23 65 / 24 

Greasewood 1,080 L/M 25 / 9 65 / 44 

Juniper 250 L 19 / 7 19 / 7 

Rock Outcrop 5,670 L 253 / 100 273 / 115 

Mined Area 4,400 L/M 247 / 94 249 / 95 

Seminoe Reservoir Lake 9,3506 NA 0 / 0 25 / 25 

Total 137,000 6,117 / 2,321 6,383 / 2 527 

Notes: 

1. Also see Table 3.6-1, Vegetation Communities; it is assumed that no acreage would be disturbed under 

Alternative A beyond that affected under the previously approved Pilot Project and gas pipeline to Walcott. 

2. See Figure 44, Vegetation Map. 

3. These represent the estimated areas of the various vegetation communities within the EIS analysis area. 

4. M means medium potential; L means low potential; L/M means low to medium potential. 

5. First number represents “initial disturbance area” in acres. Second number represents “ operational 

disturbance area” in acres. Also see Table 2-1, Preliminary Estimate of Surface Area Disturbance. 

6. Acreage at normal high water level of Seminoe Reservoir within the EIS analysis area. 

4.6.1 Effects of Alternative A (No Action)

Under the no action alternative, the Pilot Project area would be reclaimed following the termination 

of exploration activities. The road network, well pads, water treatment facilities, and associated 

disturbances would be decommissioned according to approved plans and revegetated. Vegetation 

would develop across the disturbed area in response to climatic influences, the seedbed materials 

replaced, and the revegetation techniques employed. 

As stated in Section 3.5.2.1, Pilot Project Produced Water Riparian Zones, the presence of 

continuous, low velocity flows of the Pilot Project – produced water below discharge points in Pool 

Table Draw has, in some areas, increased vegetative cover and the diversity of riparian and 

wetland species such as creeping spike rush (Eleocharis palustris), cattails (Typha latifolia), 

seaside buttercup (Ranunculus cymbalaria), and water thread pondweed (Potamogeton 

diversifolius). When Pilot Project operations cease, this trend would be reversed, produced water 

flows would be discontinued, and vegetation communities that have evolved in drainages as a 

result of these activities would revert to the type of communities that occurred prior to this 

development; possibly with an emphasis on more salt-tolerant plants. 

Seminoe Road Gas Development Project 4­53
Draft Environmental Impact Statement November 2005

That portion of the Seminoe Road Gas Development Project area proposed for future disturbance 

under this EIS would continue in its present state, subject to the vagaries of climatic influences 

and continued land use activities. Current land use trends in the region would continue including 

coal mining, oil and gas exploration ranching, and increased recreational activity. These land uses 

would cause incremental increased disturbances and some loss of vegetation productivity. 

Weed species such as tamarisk, whitetop and Scotch thistle have also been observed in areas of 

disturbance related both to Pilot Project activities and recent improvements to Carbon County 

Road 351. The drought conditions of the past several years have likewise promoted the 

propagation of competitive weedy species. 

4.6.2 Effects Common to All Action Alternatives

4.6.2.1 Upland Vegetation

Implementation of any action alternative would disturb vegetation as a result of road construction, 

well pad establishment and utility line installation. Approximately 5% of the entire EIS analysis 

area would be disturbed during the first ten years of project development (see Table 2-1, 

Preliminary Estimate of Surface Area Disturbance). Direct and indirect impacts of this 

proposed project are essentially the same in terms of size, location, intensity, and duration across 

all action alternatives with few exceptions. Direct effects to the vegetation resource include the 

removal of vegetation as a result of the construction and burial of various project components. 

The burial of gas and water collection lines, as well as electric distribution lines, would occur in 

association with road construction. This disturbance would be mitigated concurrently following 

utility line burial through trench backfilling, replacement of topsoil, and the application of approved 

revegetation techniques. Reclamation techniques for these disturbances would be completed by 

the first full growing season following disturbance to begin the re-establishment of the appropriate 

native vegetation communities. 

The construction of access roads, well pad disturbances, the two compressor facilities, and the 

water discharge facilities would entail the initial removal of vegetation from these facility sites. 

Disturbances would be confined essentially to the surface soils capable of supporting the 

identified vegetation communities leaving the remaining subsoils in place. As for the impacts 

associated with utility installation, the portions of these disturbances not needed for continuing 

operations would be reclaimed concurrently following the construction of the necessary operations 

facilities. The remaining disturbed acreage would continue in a disturbed state from initial 

4­54 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

disturbance through the life of the project or until such facilities are no longer needed and are 

reclaimed. 

The magnitude and duration of impacts related to the acreage reclaimed concurrently are reduced 

overall in comparison to other impacts due to the timely application of revegetation techniques. 

The loss of existing vegetation would reduce the plant productivity of this acreage until vegetation 

has become re-established. The time this would take cannot be calculated with certainty. It is 

assumed that acceptable revegetation on amenable sites, in terms of site stability and 

herbaceous vegetation production, can be achieved in a 5-year period given the application of the 

appropriate revegetation and weed control techniques along with a viable monitoring plan. 

Disturbed sites exhibiting low reclamation potentials due to soil physical/chemical, slope, 

erodibility, or depth limitations (see Section 4.2, Soils) could take longer to respond and require 

the application of more specific revegetation techniques and materials. 

The approach to concurrently revegetating over half of the proposed disturbance presents a 

reclamation opportunity that would benefit this project. By reclaiming all or portions of disturbed 

facilities on a regular basis through time, observations can be made regarding the success or 

failure of applied revegetation techniques and materials. As a result, the reclamation program 

would evolve eventually employing only the most efficient and cost-effective techniques and 

materials thereby enhancing the potential for success and shortening the time required to achieve 

vegetation establishment. This approach is particularly valuable given the variability of vegetation 

communities occurring over the proposed disturbed area and the characteristics of the soils that 

support them. 

The acreage associated with the operations phase of this development would remain in a 

disturbed state for the life of the project. Depending upon the year of construction, this timeframe 

would range from approximately 20 to 30 years. Less than 2% of the EIS analysis area would 

remain devoid of vegetation for the life of the project. Final reclamation of these sites would occur 

in the same manner as for the sites subject to compensatory reclamation in terms of the 

mitigation approach. However, these sites would remain unvegetated for a notably longer period 

resulting in a loss of vegetation production through time commensurate with the acreage 

remaining disturbed and unreclaimed by year. It is assumed that the timeframe required to 

achieve acceptable revegetation on amenable sites, as well as those exhibiting reclamation 

Seminoe Road Gas Development Project 4­55
Draft Environmental Impact Statement November 2005

limitations, would be essentially the same as noted above for concurrent reclamation once 

revegetation activities are initiated. 

It is reasonable to assume under all reclamation scenarios that, following the application of 

revegetation techniques, herbaceous species would become established initially with the 

development of a desired shrub component lagging due to typical shrub establishment and growth 

potentials. As compared to pre-disturbance conditions, the form, texture, and color of the 

vegetation communities establishing on disturbed sites would differ visually through time until forb 

and shrub species become established mirroring the diversity and density of adjacent, 

undisturbed vegetation communities. The narrow, linear nature of road disturbances and the 

relatively small disturbed acreage associated with well pad sites would promote the invasion of the 

desire native shrub and forb species from adjacent, undisturbed areas over time. The upland 

vegetation communities proposed to be disturbed, ranging from the Low Shrub/Mixed Grass 

across those dominated by Wyoming sagebrush, to the Playa type, are not considered rare in this 

region. 

Impacts to grazing are discussed in Section 4.8, Land Use. 

4.6.2.2 Wetland and Riparian Vegetation

All of the action alternatives have the potential to impact wetland and riparian areas, but this 

impact would principally involve road and buried utility crossings of EIS analysis area drainages. 

At these crossings, any wetland and riparian vegetation would be removed. To minimize impacts 

to wetland or riparian vegetation, the Proponent plans that such crossings would be made 

perpendicular to drainages. Road crossings of drainages would remain in a disturbed state for the 

life of the project. Final reclamation of disturbed wetland and riparian areas could take longer and 

would require more specific revegetation techniques and materials. 

4.6.2.3 Weeds

Project related surface disturbances associated with all of the action alternatives would increase 

the potential for the introduction and spread of weeds such as tamarisk, whitetop, Canada thistle, 

Russian knapweed, and Scotch thistle. 

If not controlled, weeds can become established in disturbed areas and can spread to overwhelm 

nearby native plant communities. Weeds can hinder the success of revegetation efforts and be 

4­56  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

poisonous to livestock and wildlife. In addition, weeds can threaten the grazing capacity of 

rangeland, property values, public health and safety, and general native ecosystem diversity. Tall 

weed species established adjacent to roads can create “snow-fence” effects, which can increase 

snow removal costs for roads. 

Experience gained from the Pilot Project weed management, monitoring, and reclamation efforts 

would be incorporated into the development and implementation of aggressive weed control and 

monitoring programs throughout the life of the project. The most sensitive areas for potential 

weed infestations would occur in disturbed areas along roads and utility corridors, at drainage 

crossings, and in areas surrounding treatment system and well pad sites. Site-specific weed 

management strategies would be dependent upon several factors including the location, areal 

extent and duration of disturbance and the plant species present. 

4.6.2.4 Sensitive Plant Species

Persistent sepal yellow-cress is the only BLM sensitive plant species of concern known to occur in 

the EIS analysis area. Because this species typically occurs in semi-disturbed areas, areas 

subject to flooding, and along the high water mark of standing or flowing water, only minimal 

disturbance (roads crossing drainages) would occur. Potential adverse impacts to this sensitive 

plant and its habitat could be minimized by conducting field surveys to locate populations prior to 

final well site siting and the implementation of construction activities. Although all of the action 

alternatives have the potential to affect this sensitive plant species and its habitat, it is expected 

that adverse impacts could be minimized or avoided. 

4.6.2.5 Threatened and Endangered Plant Species

No federally listed threatened or endangered plant species are known to occur within the EIS 

analysis area. Therefore, no impacts to such species are anticipated. 

4.6.3 Effects of Alternative B (Proposed Action)

Table 4.6-1, Vegetation Impact Acreage Estimates, depicts, by alterative, the acreages of each 

vegetation type to be impacted by the proposed project. Acreages for both concurrent and final 

reclamation are presented. The vegetation potentials shown, ranging from low to moderate, are 

estimates based on the observations made during the field surveys and cross-checked with 

available soil map unit data and interpretations. The low annual precipitation and high evapotransportation rates typical for the region precluded a higher potential from being considered. 

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Interim and final phase reclamation would be required on a total of 3,242 acres in vegetation types 

having a moderate reclamation potential. These vegetation map units typically occur on nearly 

level to gently rolling terrain and exhibit comparatively deeper soils, the primary revegetation 

constraints associated with these map units include moderate to high pH values, the potential for 

sandy soil textures leading to droughty seedbed conditions, and occasional steep slopes. 

Reclamation potentials ranging from low to moderate are characteristic for vegetation map units 

for which 2,603 acres of reclamation would be required. The Mixed Sagebrush and Mixed Shrub 

map units are typically among the more productive of the vegetation communities mapped on site. 

However, portions of these units occur on steeper slopes and may exhibit shallow soils that limit, 

in part, the revegetation potentials of these units. Revegetation constraints associated with the 

Low Shrub/Mixed Grass unit are predominantly allied with soil chemistry parameters including pH, 

salinity, and sodicity. Revegetation potentials of the Basin Big Sagebrush/Greasewood and 

greasewood map units are constrained by soil chemistry factors, as noted for the Low 

Shrub/Mixed Grass unit, though soils are typically deeper. Lower potentials are assumed where 

soil salinity and sodicity levels are higher, with the rating increasing to a moderate level where 

these soil characteristics are not a controlling factor. The constraints limiting the revegetation 

potential for the Disturbed map unit are varied, but revolve around the volume of suitable soil 

available for use as a growth medium. As available soil increases, the reclamation potential 

increases. 

Approximately 272 acres of reclamation would be required within vegetation map units rated as 

having a low potential for revegetation. The low potentials stem primarily from steep slopes 

combined with shallow soils, or a lack there of, and high soil coarse fragment contents for the 

Juniper and Rock Outcrop/Broken Land/Miscellaneous map units. The Playa unit is constrained 

by the potential for high soil pH values and salt and sodium levels. Added to these is the potential 

for ponding in the spring and during periods of intense rainfall. 

Under the proposed action, produced water would be discharged into ephemeral drainages and 

historically dry playas that currently are only seasonally inundated with water. Produced water 

discharge would result in the development of new wetland and riparian vegetation areas along the 

drainage areas, similar to what has occurred in Pool Table Draw (HydroGeo 2003a, 2004c). 

Hydric soils would develop, especially in areas with low gradients, where water could infiltrate into 

the ground. Although vegetation cover in most of the historically dry ephemeral drainages is 

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sparse, produced water flows could affect sagebrush and other vegetation that is unable to 

tolerate flooding and developing saturated anaerobic conditions. Produced water could cause 

erosion, sedimentation, and downcutting that could adversely impact existing and developing 

wetlands. 

Changes in plant community composition resulting from produced water discharges cannot be 

predicted with accuracy. Such changes would be dependent upon, among other factors, soil 

chemical and physical parameters, slope, amount and quality of water discharged and the timing, 

frequency and duration of such discharges. It would also depend to some degree on the 

vegetation communities, or lack thereof, currently existing in each drainage. 

It can be assumed that the existing vegetation conditions of subject drainages would change 

through time. Within the drainage zone affected by discharges, upland plants would gradually be 

replaced by species more tolerant of saturated soils and flooding. Assuming sufficient water is 

discharged throughout the growing season, wetland (hydric) species would become established to 

the general exclusion of upland species. Community gradations would likely occur typically with 

grass – like species (sedges, rushes, bulrushes, etc.) tolerant of flooding inhabiting the central 

portions of flooded drainages or in areas with continually saturated soil moisture regimes. 

Immediately upslope, or adjacent to such zones, a fringe wetland community could become 

established where intermittent flooding or subsurface irrigation gives rise to temporarily saturated 

soil conditions supporting a mixture of grass, grass-like, and forb species. This type of community 

could also dominate where drainage floor slopes are nearly level, notably wide, and saturated soil 

conditions occur throughout the majority of the growing season. Where drainage banks are 

gradually sloping, and not abrupt, a narrow wetland/upland transition zone, supporting an array of 

both upland and wetland species could form taking advantage of the enhanced soil moisture 

regime. Plant community fluctuations would normally occur as the factors noted above change. 

When flows are terminated, a plant community reversal would take place with upland species 

rapidly invading the existing wetland communities though various wetland plant species would 

continue to be present for a limited time depending upon rooting depth and above-ground 

biomass. Depending upon the quality of the water that was discharged, salt- and sodium-tolerant 

plants could dominate the resulting plant community. 

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Extensive areas of tamarisk occur along the edge of Seminoe Reservoir and the North Platte 

River. Produced water flows in historically dry ephemeral drainages could increase the potential 

for tamarisk, and other weedy species such as Canada thistle, Scotch thistle, and whitetop to 

spread and become established in drainages and playa areas receiving produced water flows for 

the life of the project. 

Because Persistent sepal yellow-cress (the only BLM sensitive plant species known to occur in 

the EIS analysis area) typically occurs along the high waterline of flowing or standing water, the 

discharge of produced water into historically dry ephemeral drainages could provide additional 

suitable habitat for this species during the life of the project. This effect would be reversed upon 

cessation of produced water pumping at the end of the project life. The discontinuation of 

pumping would cause the artificially generated habitat to disappear for this sensitive plant species. 

Produced water discharged into the playas would pool and evaporate, or infiltrate. Playas are 

closed basins that are naturally inundated by spring runoff or periods of high precipitation, but, in 

this region of south-central Wyoming, they are typically dry for extended periods of time. The 

continuous presence of water in these playas would facilitate the development of hydric soils and 

enhance development of wetland and riparian habitat. However, over time, evaporation of 

produced water, which is slightly alkaline and contains elevated concentrations of salts, could 

cause increased concentrations of these alkaline salts in the closed basins. Increasing salt 

concentrations in these playas could affect the diversity and nature of the vegetation growing in 

430 to 575 acres within and surrounding the three playas (Ferris Lake, Alkali Flats, and St. Mary’s 

Anticline Flats) found in the EIS analysis area. See Section 3.4.4, Playas Within the EIS Analysis 

Area, and Section 4.4.3.2, Effects to Playas Within the EIS Analysis Area. 

4.6.4 Effects of Alternative C (Pipeline to Reservoir)

The disturbances proposed under this alternative would result in similar impacts to vegetation as 

described for Alternative B in Section 4.6.2, Effects Common to All Action Alternatives and 

Section 4.6.3, Effects of Alternative B (Proposed Action), with one exception. No water would be 

discharged into drainages or playa areas. Rather, pipelines, located away from drainages, would 

discharge water directly into the North Platte River and/or Seminoe Reservoir. Under Alternative 

C, there would be no development or enhancement or hydrophytic vegetation and/or hydric soils 

along the drainages or within playa areas. The potential spread of weeds including species such 

as tamarisk would be lower than with the proposed action, since there would be no continuous 

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flows of produced water in the drainages. In addition, there would be no need for reclamation of 

the playas. 

The pipeline constructed to convey process water to the river and/or reservoir would require the 

removal of vegetation. This disturbance would be reclaimed following pipeline burial to stabilize 

the disturbed area and reestablish native plant communities. 

Pipeline or road drainage crossings could adversely impact existing wetlands and persistent sepal 

yellow-cress habitat. 

4.6.5 Effects of Alternative D (Underground Injection)

With underground injection, the effects of Alternative D to vegetation would be similar to the 

effects of Alternative C. See Section 4.6.4, Effects of Alternative C (Pipeline to Reservoir). The 

areal extent of surface disturbance and potential for spreading weedy species would be 

proportionally lower with this alternative than with the proposed alternative or Alternative C. 

Groundwater model results (HydroGeo 2004a) indicate that the development of surface springs 

could potentially enhance small, localized areas of suitable habitat for persistent sepal yellowcress. When the project operations cease, this effect would be reversed. 

4.6.6 Cumulative Impacts

Current land use practices that contribute to cumulative impacts on vegetation communities 

include coal mining, oil and gas exploration and development, range management activities (such 

as grazing) and recreational use. Potential short-term incremental cumulative impacts to wetland 

and riparian areas are anticipated from present and foreseeable activities in the region. 

Information is not available to allow for a quantitative analysis of impacts to these sites. Current 

and future uses combined with the proposed Seminoe Road Project operations would continue to 

create surface disturbances that provide potential habitat for weeds to be introduced, spread, 

and/or become established. Minimizing the areal extent and duration of surface disturbances and 

implementing aggressive reclamation monitoring, and weed control programs would minimize the 

potential spread of weedy species in the EIS analysis area. Actual cumulative surface disturbance 

and vegetation removal associated with other potential projects in the area is expected to be low, 

thus actual vegetation disturbance and removal would likewise not contribute to any major 

regional cumulative impacts. Grazing levels and disturbance from grazing is expected to remain 

relatively constant. 

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Livestock tend to concentrate in areas where density of grass cover is the highest (e.g., channel 

bottoms, edges of drainages, in wetlands and riparian areas, and near stock ponds). The 

continuous presence of produced water in drainage channels would attract cattle and increase the 

potential for soil compaction and trampling and could contribute to the inadvertent introduction of 

weedy species in and around wetlands and riparian areas. To prevent cumulative impacts, careful 

range management practices must be maintained such that livestock use would not over graze an 

area or cause trampling of vegetation, which can subsequently cause an influx of weeds. Given 

current range management practices in the region and oversight by BLM range management 

specialists for activities on BLM-administered lands, no substantive cumulative impacts from such 

practices are anticipated. 

Since there are no known occurrences of threatened, endangered, candidate or proposed plant 

species and/or critical habitats in the EIS analysis area, no incremental increase in impacts is 

expected from current or foreseeable activities in the area. 

Activities within and surrounding the EIS analysis area could cause impacts to populations and habitat 

to sepal yellow-cress, a BLM sensitive species, but these impacts would be minor because most 

activities avoid disturbing the riparian habitat where this species is known to exist. 

4.6.7 Potential Monitoring and Mitigation

No vegetation monitoring and mitigation measures are proposed beyond those committed by the 

Proponent in Section 2.8.5, Vegetation; Section 2.8.6, Weeds; Section 2.8.13, Wetlands, Special 

Aquatic Sites and Waters of the U.S; and Section 2.8.16, Threatened, Endangered, and 

Proposed, Candidate and Sensitive Species. 

General revegetation plans set forth in Appendix F, Reclamation Plan, need to be finalized in 

advance of construction. 

4.7 Wildlife/Fisheries

Wildlife Impact Significance Criteria: Wildlife impacts would be considered significant if: 

� The project resulted in non-compliance with existing BLM, USFWS, or Wyoming 

Game and Fish Department wildlife management objectives for natural gas mineral 

developments; 

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November 2005 Draft Environmental Impact Statement

� The project caused a substantial increase in direct wildlife mortality due to road kills; 

� There was total elimination or a sustained reduction of crucial wildlife habitat in the 

project area; 

� The project resulted in a long-term decline in recruitment and/or survival of a wildlife 

population; 

� The project caused disruption of greater sage-grouse, or raptor breeding or nesting 

activities to the extent that reproductive success is impaired; 

� The project jeopardized or substantially decelerated the recovery program of any 

USFWS listed or proposed species; 

� The Biological Assessment (prepared for compliance with Section 7 of the 

Endangered Species Act of 1973) concluded a “likely to adversely affect” any listed 

threatened or endangered species; this designation would trigger formal USFWS 

consultation, or 

� The project jeopardized the persistence of any BLM Wyoming state sensitive wildlife 

or fish species. 

General effects on for wildlife are the physical loss of habitat; displacement of wildlife; habitat 

fragmentation and isolation; increased competition for wildlife and fishery resources; and impacts 

to threatened, endangered, and sensitive species. These effects can be classified as short-term 

and long-term. Short-term impacts arise from habitat removal and disturbance, as well as from 

activities associated with construction, drilling and production. These impacts would cease upon 

project closure and completion of successful reclamation. Long-term impacts would consist 

primarily of permanent changes to habitats and the wildlife populations dependent on those 

communities. 

4.7.1 Effects of Alternative A (No Action)

Under the no action alternative, there would be no direct disturbance or indirect effects to wildlife, 

wildlife habitat and fisheries from the proposed build-out of the Seminoe Road Project. However, 

current land use trends in the area would continue, including Pilot Project operation, potential for 

increased oil and gas development, coal mining, and increased recreational use, such as hunting, 

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Draft Environmental Impact Statement November 2005

camping, fishing and boating. These land use trends would have continued effect on wildlife 

populations and habitat. 

Deer and pronghorn populations in the region are expected to remain stable into the near future. 

Sage-grouse populations statewide seem in decline, although there is no documented evidence 

as to the reasons, wildlife specialists from the BLM, USFWS, and WGFD believe that drought 

conditions of the past decade and increased natural resource development activities (such as oil 

and gas exploration and development) may be contributing factors. There are no established 

trends for other wildlife species in the area, and wildlife populations seem to be stable. 

4.7.2 Effects Common to All Action Alternatives

The principal effects to wildlife and fisheries populations under all action alternatives would be 

direct habitat removal or alteration, increased human presence and activities, and habitat 

fragmentation and isolation. These potential effects are expected to be the same for each action 

alternative. Impacts to threatened, endangered and sensitive species are also discussed in this 

section. 

4.7.2.1 Physical Loss of Habitat

Direct habitat losses would result from well pad, access road and utility line construction, and 

indirectly from increased human presence (see Table 2-1, Preliminary Estimate of Surface 

Area Disturbance). 

Direct habitat losses would account for approximately 4.5% of the total project area. With interim 

reclamation, these direct habitat losses would be reduced over time to 1.7% of the project area 

(see Table 2-1, Preliminary Estimate of Surface Area Disturbance). 

Final reclamation would be implemented after project closure and would focus on replacement of 

existing grassland and shrub communities. With successful revegetation, there should be no longterm net loss of habitat within the EIS analysis area. 

Disturbed habitats would be anticipated to recover to a productive state for grasses and shrubs 

over a 3 to 5 year period after reclamation, but vegetation succession toward mature sagebrush 

and other shrub habitats could take 20 years or more. 

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November 2005 Draft Environmental Impact Statement

4.7.2.2 Displacement of Wildlife

The most common wildlife responses to noise and human presence are avoidance and 

accommodation. 

Displacement is unavoidable in the short-term under all action alternatives, and this displacement 

has the potential to be the most significant effect on wildlife. Avoidance of disturbed areas would 

result in wildlife displacement from an area larger than the actual disturbed sites. The extent of 

displacement would be related to the duration, magnitude, and the visual prominence of the 

activity, as well as the extent of construction and operational noise levels above existing 

background levels. Visual prominence of facilities is dependent upon surrounding topography. 

Displacement would result in local reductions in wildlife populations if adjacent, undisturbed 

habitats are at carrying capacity. In this situation animals are either forced into less than optimal 

habitats or they compete with other animals that already occupy unaffected habitats. Possible 

consequences of such displacement are lower survival, lower reproductive success, lower 

recruitment, and ultimately lower carrying capacity and reduced populations (Oil and Gas 

Mitigation Working Group 2004). 

Reaction of animals to noise and human presence varies depending on the intensity of the noise 

source and whether it is continuous or intermittent. Transient loud noises would provoke alarm 

responses; however, many animals learn to ignore more constant, lower level noise sources that 

are not associated with negative experiences such as being chased or hunted (Busnel 1978). 

The extent of wildlife displacement is impossible to predict for most species since the response 

severity varies from species to species and can even vary between different individuals of the 

same species. After initial avoidance, some wildlife species (usually certain birds and rodents and 

to a lesser extent deer and pronghorn) may acclimate to the activity and begin to reinvade areas 

previously avoided. This acclimation and reoccupation would be expected to occur following 

construction and drilling when the project moves into the production phases where less noise and 

human activity would take place. Acclimation to activity may increase predation on some species. 

Construction and drilling noise have the potential of affecting wildlife species at the project site as 

well as areas surrounding disturbance sites. Man-made construction such as well pads and roads 

can reduce use of surrounding habitat by wildlife. These impacted sites reduce foraging due to the 

direct loss of native vegetation from ground disturbance. In addition, there is an area surrounding 

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these sites that tends not to be utilized due to the increased human activity. This “zone” can 

extend up to a half mile from the developed area. Consequently, development impacts to wildlife 

can extend further offsite than the actual amount of disturbed area. Although some individual 

animals can habituate to the increased infrastructure, it is generally assumed that, overall the 

increased human footprint on a previously lightly developed area is detrimental to big game 

species. In addition to the avoidance response, increased human presence intensifies the 

potential for wildlife-human interactions ranging from the harassment of wildlife to poaching and 

increased legal hunting pressure. Also, increased traffic levels on new and existing roads could 

increase the potential for wildlife-vehicle collisions. Following drilling and well completion 

operations, noise levels would be essentially eliminated because well pumps would be powered 

by electric motors. As a result, species might acclimate to the well pad production facilities and 

utilize habitats immediately adjacent to such sites. This has been observed at other natural gas 

production sites in Wyoming. 

4.7.2.3 Habitat Fragmentation and Isolation

Habitat fragmentation and isolation are difficult to determine and probably vary species to species 

but they could occur as a result of gas field developments, which are typically configured as point 

and linear disturbances scattered throughout broader areas. Although these types of disturbances 

(well pads, utility lines and access roads) do not usually create physical barriers to wildlife 

movement, the effective use of adjacent undisturbed habitats could diminish as densities of well 

pads, utility lines and roads increase. A total of 270 miles of new roads, 200 miles of upgraded 

existing roads, and 470 miles of utility lines (gas, water, electric) are proposed to be constructed in 

the 137,000 acre EIS analysis area under all action alternatives. Habitat fragmentation and 

isolation can be problematic in areas of limited habitat such as crucial big game winter range and 

sage-grouse breeding areas. 

The BLM standard mitigation stipulation of restricting or prohibiting surface occupancy in big game 

crucial winter range (November 15 – April 30) would limit impacts to big game crucial winter 

range; however, the action alternatives would result in the construction of approximately 42 miles 

of new or upgraded roads and 42 miles of pipelines within pronghorn and mule deer crucial winter 

ranges. 

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The greatest concern for habitat fragmentation and isolation within the EIS analysis area would 

involve sage-grouse leks. See Figure 45, Wildlife Map. Additional discussion on sage-grouse is 

set forth in Section 4.7.2.14, Sensitive Species. 

4.7.2.4 Wildlife Mortality

During construction, most larger, mobile wildlife species would be displaced to adjacent 

undisturbed habitats; however, direct habitat disturbance could result in some direct losses of 

smaller, less mobile species of wildlife, such as small mammals, reptiles and ground nesting 

birds. 

Predictions of wildlife population losses based on habitat disturbance and displacement are hard 

to make since accurate information on wildlife population numbers is difficult to obtain for many 

species. Even if accurate population numbers were available, projections of losses may not be 

accurate since it is impossible to account for the effects of weather and natural cyclical population 

changes. If it is assumed that the existing adjacent habitats are at carrying capacity for most 

species, locally displaced populations may be eliminated until final reclamation is successful. 

However, due to their relatively high reproductive potentials, populations of most small mammals, 

reptiles and birds would be expected to rapidly recover once construction and production activities 

are complete. Similarly, with successful reclamation, other wildlife species would be expected to 

reutilize the once disturbed areas. However, successful reclamation, especially for sagebrush and 

other shrub habitats, may take 5 to 20 years or longer. 

Although roads would access well pad sites, overall public access to the EIS analysis area would 

be limited. The Proponent plans to locate site access from public roads (i.e., Carbon County Road 

351) to private surface, where gates can be kept closed and/or locked. Although there may be 

increased access roads in the area, this should not translate to an increased legal or illegal 

harvest of mule deer and pronghorn. 

Mule deer and pronghorn road kills along Carbon County Road 351 have not been a major 

problem in the past, although nearly 50% of the accidents reported for this road do involve animalvehicle collisions. See Section 4.12, Transportation. Increased human presence and subsequent 

related increases in traffic levels, specifically on Carbon County Road 351, could result in more 

animal-vehicle collisions. The potential for animal-vehicle collisions is typically highest in the early 

morning and evening hours and where roads traverse areas where big game concentrates. The 

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risk of animal-vehicle collisions is expected to be relatively low on the project-internal graveled 

access roads because of low speed limits. 

4.7.2.5 Increased Competition for Wildlife and Fishery Resources

The level of increased competition for wildlife and fishery resources is unknown. Currently, 

hunting access within the EIS analysis area is limited given the checkerboard ownership pattern. 

However, private guided hunting groups do utilize the project area (see Section 3.11, Recreation). 

Hunting and fishing is expected to increase in the general area as recreation activities increase. 

However, given hunting and fishing management policies of the WGFD, no detrimental increased 

competition for wildlife and fishery resources is anticipated. 

4.7.2.6 Wildlife Threshold Classifications

The WGFD has recently developed criteria for wildlife impact thresholds and mitigation 

recommendations for oil and gas development projects (Oil and Gas Mitigation Working Group 

2004). The impact thresholds are based on the density of well locations and the cumulative 

disturbance (acres) per section, and the WGFD describes impacts as “moderate”, “high”, or 

“extreme”. 

Given the relative density of wells for the Seminoe Road Project (four wells per 1-mile square 

section) and cumulative disturbances of up to 28.6 acres per 1 square mile section, the wildlife 

impacts created within the EIS analysis area would be considered “low” to “moderate” for most 

species. Given the number of sage-grouse leks in the EIS analysis area (see Figure 45, Wildlife 

Map), special attention and mitigation measures would be needed for any construction and drilling 

activity within 2 miles of a lek. For more information about sage-grouse, see Section 4.7.2.14, 

Sensitive Species. The 28.6-acre average initial construction disturbance per section (640 acres) 

assumes a 75-foot wide ROW disturbance for roads, and pipelines and utilities. In reality, total 

ROW disturbance would probably be less; the actual Pilot Project initial construction disturbance 

width for roads and pipelines averaged around 30 feet. Under a 30-foot disturbance corridor, the 

average disturbance per section would be approximately 20 acres. Interim reclamation would 

reduce the initial construction disturbance per section by almost 60%. Even using the 75-foot 

ROW, the long-term disturbance per section would be reduced to 16.6 acres. This reduces the 

WGFD impact category to moderate for most species. 

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4.7.2.7 Big Game

Mule deer and pronghorn are expected to be displaced within the immediate area of construction 

activities (well pad construction, road building and utilities installation) and drilling operations. 

Displacement would occur in the immediate vicinity of the construction or drilling activity due to 

noise and human presence; however, most pronghorn should move back into the area upon 

completion of the construction or drilling activity. Mule deer populations are more sensitive and 

may not return to pre-project levels for the life of the project. As the project is put into production, 

there would be little noise related impacts because well pumps and compressors would be 

powered with electricity. Traffic and human presence would be associated with ongoing 

operational production and maintenance activities; however, mule deer and pronghorn would be 

expected to habituate to some extent to the periodic traffic and human presence. 

The majority of the EIS analysis area is outside occupied mule deer range. However, a small 

portion of crucial winter/yearlong mule deer range is located within the southeast corner and the 

extreme northwest corner of the EIS analysis area. See Figure 45, Wildlife Map. There is no 

development activity planned in mule deer crucial winter range in the northwest part of the EIS 

analysis area, and only minor development (five wells) is planned in crucial winter range in the 

extreme southeast corner of the EIS analysis area. Given the general avoidance of crucial winter 

range, no significant impacts to mule deer populations are expected as a result of the Seminoe 

Road Project. 

For pronghorn, most gas development would be within winter/yearlong range, which is not 

considered limiting to pronghorn populations. However, portions of crucial winter/yearlong range 

would be impacted in the western and northwest portions of the project area. In pronghorn crucial 

winter/yearlong range, the total possible maximum disturbance resulting from well development 

and road construction would be 28.6 acres per 1-mile square section. This level of disturbance 

would exceed the “moderate” category specified by the WGFD (Oil and Gas Mitigation Working 

Group 2004) though the number of wells would not exceed four per section, which does meet the 

“moderate” impact category. As indicated in Section 4.7.2.6, Wildlife Threshold Classifications, the 

average of 28.6 acres of disturbance per section represents disturbing a 75-foot construction 

ROW for roads and utilities and actual disturbance per section would likely be closer to the 20 

acres per section threshold level. Given additional careful design of development layout schemes, 

the Proponent should be able to reduce the total acreage of disturbance within pronghorn crucial 

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winter/yearlong range to less than or equal to 20 acres, which would not exceed the “moderate” 

category. In addition, each phase of the Seminoe Road Project would require an APD and an EA, 

and project planning within pronghorn crucial winter/yearlong range may need to be revised to 

maintain disturbance levels within the “moderate” category. Once short-term disturbances are 

reclaimed, the average acreage of disturbance per section would be below the less than 20-acre 

requirements to meet the “moderate” impact classification. 

Under the “moderate” category of impact, “impacts can be minimized or avoided through effective 

management practices and habitat treatments” (Oil and Gas Mitigation Working Group 2004). 

Therefore, significant impacts to pronghorn populations in the project area are not likely if 

appropriate mitigation measures are implemented. 

The BLM stipulation of prohibiting construction and other activities potentially disruptive to 

wintering wildlife during the period of November 15 to April 30 for the protection of big game 

winter habitat would minimize the potential for direct and indirect disturbance of wintering mule 

deer and pronghorn during construction phases. It does not address the potential loss of wintering 

habitat due to the presence and operation of wells in winter range for the life of the project after 

construction is complete. The BLM may need to consult with the WGFD to determine what 

additional mitigation measures may be necessary to minimize the impacts. Not all areas of 

designated crucial winter range are of equal quality. Habitats with better quality and quantity of 

forage and topography and/or vegetation that provide cover from extreme weather conditions 

provide higher quality crucial winter habitat. 

4.7.2.8 Predators, Furbearers and Small Mammals

Predators and furbearers are typically shy, some being wide ranging; they typically avoid areas 

with human activities. Construction activities may cause these animals to avoid the site of activity, 

but this effect would be relatively short-term and temporary. Similarly, a small reduction in prey 

base could affect the populations of these species, but such effects are not expected to be 

significant. Following construction and drilling, they would move back into the area, but they may 

continue to avoid any areas of human presence. Many of these species are secretive and mainly 

nocturnal. Much of the construction would be conducted during daylight hours, although drilling 

would be conducted on a 24-hour schedule. 

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Construction activities could result in some direct losses of smaller, less mobile mammal species 

such as voles, cottontails, and deer mice. In addition, these species could be displaced from 

areas construction and development. However, reclamation that would occur following 

construction would minimize long-term disturbance and provide favorable grassland habitat for 

many of these species. 

4.7.2.9 Waterfowl

No impacts are projected for habitats utilized by this group of species. Based on the analysis 

provided in Section 3.5.3, Hanna Basin Alluvial Ground Water Systems, no water quality or 

quantity impacts are anticipated for Seminoe Reservoir or the North Platte River. Therefore, 

waterbird use of these water bodies as well as adjacent wetland habitats is not likely to change. 

4.7.2.10 Raptors

Raptor nesting activity could potentially be affected by construction activities within 0.5 mile to 1.0 

mile of active nest sites, depending on topography and direct line-of-sight exposure to 

development activities. In addition, raptor foraging activity and prey populations could be impacted 

by project development. Potential impacts to raptors include: 1) nest desertion or reproductive 

failure because of project activities or proximity of new roads, 2) reductions in prey populations, 

and 3) mortality associated with roads. The primary potential impact to raptors with project 

development would be nest disturbance resulting in reproductive failure. To minimize this potential 

the BLM stipulates that there would be no construction activity within 3/4 to 1 mile of active or 

inactive nest according to the time constraints set forth in Table 2-2, Raptor Nest Protection 

Dates. Raptor nest surveys would also be required for all new disturbance areas prior to 

construction to locate any potential nest sites that may not be recorded in the BLM’s or WGFD’s 

raptor nesting map database. The nature of the restrictions, exclusion dates, and the protection 

radius would vary depending upon activity status of nests, species involved, natural topographic 

barriers, and line-of-sight distances and would be determined by the BLM on a case-by-case 

basis. Buffer restrictions are important for inactive nest sites since an inactive nest may be used in 

subsequent years and precluding development near these nests may ensure these nests are 

suitable for use in future years. 

To prevent impacts on raptor breeding activity, the Proponent has committed to avoiding 

construction and drilling activity that might affect occupied raptor nests. See Section 2.8.15, 

Wildlife and Fisheries. With the implementation of this Proponent-proposed environmental 

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protection measure, there would be no anticipated adverse effects on nesting raptors in the 

project area. 

4.7.2.11 Upland Game Birds

Discussion of impacts on the greater sage-grouse is provided in Section 4.7.2.14, Sensitive 

Species. 

4.7.2.12 Migratory Songbirds

Construction activities (e.g., well pad and road construction, utilities line installation) have a 

potential for unintentional loss of ground or shrub nesting species, primarily during the avian 

breeding season, but ground-dwelling species could be impacted outside the breeding season as 

well. 

Species of greatest management concern are the migratory birds of Conservation Concern listed 

by the USFWS for the region of the project area (USFWS 2002). These birds of Conservation 

Concern are comprised entirely of waterbirds, raptors, or BLM listed sensitive species. Potential 

impacts to raptors and waterbirds were discussed in preceding sections. Potential effects on BLM 

sensitive species are discussed under Section 4.7.2.15, Sensitive Species. 

4.7.2.13 Fisheries

Short-term, local increases in turbidity and suspended sediments could occur in drainages 

adjacent to construction activities, but, because construction activities are remote from the 

Seminoe Reservoir and the North Platte River, the impact of increased sediment levels on aquatic 

species and their habitat would be low. The Miracle Mile, below Kortes dam, would not be affected 

by any project-related sediment generation. Sediment concentrations would stabilize and return to 

typical background concentrations after construction activities are completed. 

As explained in Section 4.4, Surface Water, under Section 4.4.1, Effects of Alternative A (No 

Action), WET tests showed no impacts on aquatic organisms from produced water. The 

conductivity of produced water (1,580 μmhos/cm) is below the 2,000 μmhos/cm, a threshold value 

where concentrations of dissolved solids maybe sufficient to cause acute toxicity to aquatic 

organisms (Goodfellow et. al. 2000). The volume of produced water to be discharged annually 

represents a volume less than one percent of Seminoe Reservoir’s total capacity. Given this 

disproportionate mixture of the two waters, conductivity in the Seminoe Reservoir water is 

4­72 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

expected to remain in it’s current range of 500 to 600 μmhos/cm. Therefore, given the above 

referenced threshold value, there would be no impacts to aquatic resources from conductivity in 

Seminoe Reservoir, or downstream in Miracle Mile. See Section 4.4.3.5, Effects to Seminoe 

Reservoir, and Section 4.4.3.6, Effects to Miracle Mile. 

The use and transport of fuels to the construction and operational facilities could represent a risk 

to aquatic species and their habitat, if a spill or accident was to occur adjacent to the North Platte 

River. Based on the expected frequency of traffic and mitigation measures employed by trucking 

firms, the risk of a fuel spill or leak reaching the North Platte River, is considered extremely low. 

See Section 4.15, Accidents and Spills. 

4.7.2.14 Sensitive Species

The BLM has identified a number of sensitive species potentially occurring within and adjacent to 

the EIS analysis area. This section describes the expected impacts on those sensitive species. 

White­tailed Prairie Dog. White-tailed prairie dog towns are located in low shrub/mixed grass, 

threadleaf sedge/mixed grass, mixed grass, and disturbed site habitats throughout the EIS 

analysis area. See Figure 44, Vegetation Map. Project development and construction activities in 

these habitats could impact prairie dog towns. Under BLM sensitive species policies, the BLM 

would require the operator to locate development sites outside of prairie dog towns whenever 

possible. Although project development may result in some short-term reduction in white-tailed 

prairie dog populations, these species have a high reproductive potential and should rapidly 

recover following concurrent and final reclamation activities. Additional habitat would also be 

available for these species as reclamation of disturbed shrublands would result in open grassland 

habitats that would be readily reoccupied by prairie dogs. 

Swift Fox. The EIS analysis area is near the periphery of the known range of the swift fox, and 

expanses of shortgrass prairie preferred by this species are generally lacking. In the unlikely event 

that swift foxes inhabited the EIS analysis area, this species, like other predators, would avoid 

areas of construction and development. 

White­faced Ibis, Trumpeter Swan, Long­billed Curlew. These species would not be 

impacted by construction or production activities of the Seminoe Road Project. Their habitat of 

riparian areas surrounding permanent stock ponds or marshy wetlands and riparian areas along 

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Draft Environmental Impact Statement November 2005

the North Platte River would remain undisturbed. Under Alternative B, Proposed Action, produced 

water discharged into the three closed playa basins (St. Mary’s anticline basin, Alkali Flats, and 

Ferris Lake) located in the southern portion of the EIS analysis area would create additional 

habitat, which could increase the use of the area by white-faced ibis and long-billed curlew. 

Mountain Plover. Mountain plovers utilize low shrub/mixed grass, thread-leaved sedge/mixed 

grass, mixed grass, disturbed sites, and playa habitats and are often found in association with 

prairie dog towns. Project development and construction activities would result in minor losses of 

mountain plover habitat. The Proponent would prohibit construction in suitable mountain plover 

habitat from April 10 through July 10 (see Section 2.8.16, Threatened, Endangered, Proposed, 

Candidate and Sensitive Species); therefore, impacts to mountain plovers would be minimized. 

Although project development may cause some short-term reduction in mountain plover habitat, 

these species should return to the area following concurrent and final reclamation activities. 

Additional habitat would be available as reclamation of disturbed shrublands would result in a 

long-term (20 years or more) increase in open grassland habitats favored by mountain plover. 

Peregrine Falcon. Peregrine falcons may fly over the construction and production sites of the 

EIS analysis area, but their preferred foraging habitat would be primarily along the North Platte 

River. No impacts are anticipated to this species as a result of the Seminoe Road Project. 

Ferruginous Hawk. Ferruginous hawks are generally shy of human activity and presence; 

project construction and development activities within the EIS analysis area are likely to reduce 

the total extent of foraging habitat for this species. Nesting activity would be protected by standard 

BLM nest protection stipulations. 

Burrowing Owl. Burrowing owls rely on prairie dog towns for nesting, foraging and protective 

cover. Because project development and construction activities could result in minor loss to prairie 

dog towns, there would be a subsequent reduction in available burrowing owl habitat. Habitat for 

prairie dogs, and subsequently burrowing owls would be restored following interim and final 

reclamation activities. There would be an overall gain in potential habitat for prairie dogs (and thus 

burrowing owls) as disturbed mature shrublands would be initially re-established as open 

grassland habitats that would attract prairie dogs. 

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November 2005 Draft Environmental Impact Statement

Greater Sage­grouse. Sage-grouse leks exist in and within 2 miles of the EIS analysis area. 

See Figure 45, Wildlife Map. 

In Wyoming, information suggests that greater sage-grouse populations are negatively affected by 

energy development activities, especially those that degrade important sagebrush habitat, even 

when mitigation measures are implemented (Braun 1998, Lyon 2000). Greater sage-grouse 

populations can repopulate areas developed for resource extraction after habitat reclamation for 

the species (Braun 1987). However, there is no evidence that populations attain their previous 

levels and reestablishment of sage-grouse in a reclaimed area may take 20 to 30 years, or longer 

(Braun 1998). BLM mitigation standards are established to ensure that energy development 

projects do not exacerbate greater sage-grouse declines on either a local or range-wide level. 

Sage-grouse leks ­ 1) Avoid surface disturbance or occupancy within 0.25 mile of the 

perimeter of occupied sage-grouse leks. 2) Avoid human activity between 8 p.m. and 8 a.m. 

from March 1 through May 15 within 0.25 mile of the perimeter of occupied sage-grouse leks. 

Sage-grouse nesting/early brood-rearing habitat ­ Avoid disturbing the disruptive activities 

in suitable sage-grouse nesting and early brood-rearing habitat within 2 miles of an occupied 

lek, or in identified sage-grouse nesting and early brood-rearing habitat outside the 2-mile 

buffer from March 15 through July 15. 

Sage-grouse winter habitat ­ Avoid disturbance and disruptive activities in sage-grouse 

winter habitat from November 15 through March 15. 

The Proponent has committed to these protection measures as stated in Section 2.8.15, Wildlife 

and Fisheries. 

The level of disturbance per 1-mile square section could be as high as 28.6 acres, with four wells 

per section. This level of development would result in “moderate” category specified by the WGFD 

(Oil and Gas Mitigation Working Group 2004) though the number of wells would not exceed four 

per section, which does meet the “moderate” impact category for sage-grouse. As indicated in 

Section 4.7.2.6, Wildlife Threshold Classifications, the average of 28.6 acres of disturbance per 

section represents completely disturbing 75 feet of construction ROW for roads and utilities and 

actual disturbance per section would likely be closer to the 20 acres per section threshold level. 

Given additional careful design of development layout schemes, the Proponent should be able to 

Seminoe Road Gas Development Project 4­75
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reduce the total acreage of disturbance within sage-grouse nesting and brood-rearing habitat to 

less than or equal to 20 acres. In addition, each phase of the Seminoe Road Project would require 

an APD and an EA, and project planning within sage-grouse nesting and brood-rearing habitat 

may need to be revised to maintain disturbance levels within the “moderate” category. Once shortterm disturbances are reclaimed, the average acreage of disturbance per section would be below 

the less than 20-acre requirement to meet the “moderate” impact classification. 

Under the “moderate” category of impacts, “impacts can be minimized or avoided through 

effective management practices and habitat treatments” (Oil and Gas Mitigation Working Group 

2004). Significant impacts to sage-grouse populations in the EIS analysis area are not likely if 

appropriate mitigation measures are implemented. 

Loggerhead Shrike, Sage Thrasher, Sage Sparrow, Brewer’s Sparrow. These avian 

species utilize sagebrush habitats. Project development and construction activities would result in 

the loss of approximately 1 to 2% of sagebrush habitat within the EIS analysis area for the life of 

the project (30 years) and up to an additional 20 years until mature sagebrush habitats reestablish following final reclamation activities. Construction of roads and well pads, along with the 

installation of buried utility lines, in sagebrush habitats could displace these species and possibly 

eliminate nest sites. 

Northern Leopard Frog. The northern leopard frog is a highly aquatic species and is usually 

found in close association with banks and shallow water areas of permanent marshes, ponds, 

streams, lakes and reservoirs. Water bodies with rooted aquatic vegetation are preferred. No 

impacts to populations of the northern leopard frog are anticipated as a result of the Seminoe 

Road Project because permanent stock ponds and backwater areas of the North Platte River with 

rooted emergency vegetation would not be directly affected by project development and 

construction. 

4.7.2.15 Threatened and Endangered Species

Impacts to threatened and endangered species would be similar for all alternatives and result 

from removal of potential suitable habitat and displacement from increased human activity. 

Black­footed Ferret (Federal Endangered). No black-footed ferret sightings have been 

made within and surrounding the Pilot Project area during surveys in 2000, 2001, 2002, and 2003. 

4­76  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

White-tailed prairie dog towns or complexes greater than 200 acres represent potential habitat for 

black-footed ferrets, and, if development within such habitat cannot be avoided, the USFWS 

requires ferret surveys within 1 year of planned development. If no ferrets are found, the prairie 

dog town would be cleared for development for the next year. Although no black-footed ferrets 

have been sighted within the area of past activity (Pilot Project), annual surveys for black-footed 

ferrets would be necessary in white-tailed prairie dog towns or complexes greater than 200 acres 

for development and construction. At this time, it is not possible to predict if black-footed ferrets 

would be found but, given past survey results, future annual surveys and appropriate mitigation 

(avoidance if black-footed ferrets are found), project development is not likely to adversely affect 

black-footed ferrets within the EIS analysis area. 

Bald Eagle (Federal Threatened, Proposed for De­listing). Suitable nesting and winter 

roosting habitat exists along the North Platte River within the EIS analysis area, and bald eagles 

may fly over the more upland sites within the region. The BLM has identified two potential nest 

sites along the river that need to be verified. To prevent disturbance of any bald eagle nest sites, 

the Proponent, would only allow construction activities to occur within a mile of any occupied nest 

site between August 1 and February 1. This restriction would preclude any disturbance to nesting 

eagles. 

North Platte River Species. No suitable habitat exists within or near the EIS analysis area for 

whooping crane (endangered), least tern (endangered), pallid sturgeon (endangered), Eskimo 

curlew (endangered) and the piping plover (threatened). Important habitat areas do exist for these 

species along downstream portions of the Platte River system, particularly in Nebraska. No water 

depletions in the North Platte River are expected as a result of production from the Mesaverde 

formation at the Seminoe Road Project. See Appendix L, Biological Assessment. The BLM 

would continue to coordinate and consult with the U.S. Fish & Wildlife Service on potential 

impacts to downstream threatened and endangered species once the exact method of produced 

water discharge is established and before production from the Fox Hill/Medicine Bow formations 

to assess any depletions in the North Platte River. 

4.7.3 Effects of Alternative B (Proposed Action)

Wildlife impacts for Alternative B would be the same or similar to those discussed in Section 

4.7.2, Direct Effects Common to All Action Alternatives. 

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Draft Environmental Impact Statement November 2005

Discharge of produced water in drainages and closed playa basins could provide benefit to wildlife 

species. Produced water discharge would result in the development of narrow, linear habitats 

along discharge drainages (similar to what is currently happening in Pool Table Draw as a result 

of Pilot Project produced water discharges). This would provide additional short-term habitat for 

waterfowl and short-term watering areas for other types of wildlife, including mule deer and 

antelope. Further, the year-round inundation of the three closed playa basins (St. Mary’s anticline 

basin, Alkali Flats and Ferris Lake) in the southern portion of the EIS analysis area could create 

additional wildlife watering area. However, losses of existing sagebrush and other habitats, 

including playa, would occur as a result of these gains in surface water and wetlands. 

The vegetative habitats created through the discharge of produced water would disappear at the 

completion of the project and would revert to pre-project conditions. Any increase in wildlife 

populations as a result of these artificially created or enhanced vegetative communities would 

likewise diminish at the close of the project. 

4.7.4 Effects of Alternative C (Pipeline to Reservoir)

Impacts to wildlife under this alternative would be the same as set forth in Section 4.7.2, Direct 

Effects Common to All Action Alternatives. Under this alternative, produced water would be piped 

directly to the North Platte River and Seminoe Reservoir rather than being released in drainages 

(Alternative B) or discharged through underground injection (Alternative D). Water quality and 

quantity effects to the North Platte River and Seminoe Reservoir would be similar to those 

described before the proposed action (Alternative B) except the quantity of produced water 

reaching those receiving waters would be greater. The increase in available water would provide 

additional water to downstream portions of the Platte River system, which, in turn, could provide 

additional benefits to the threatened and endangered species in this river system, particularly in 

Nebraska. 

4.7.5 Effects of Alternative D (Underground Injection)

The effects of this alternative would be similar or the same as those discussed in Section 4.7.2, 

Direct Effects Common to All Action Alternatives. However, there would be no creation of 

enhanced vegetative habitats along drainages and in playa areas, and no produced water would 

be available for down stream benefits. 

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November 2005 Draft Environmental Impact Statement

4.7.6 Cumulative Impacts

Historic and ongoing land uses in the area have resulted in the loss of some native wildlife 

habitats. Land use practices that contribute to cumulative effects on vegetation communities and 

wildlife habitats include coal mining, oil and gas exploration and development, grazing, and 

increased recreational use for hunting and other dispersed recreation. Increased and ongoing 

human presence in the area would cause cumulative effects to big game and other wildlife 

species through vehicle mortalities, increased legal or illegal hunting, noise effects, and 

harassment. In the context of cumulative impacts, any proposed disturbance, especially linear 

disturbance such as new roads, incrementally add to wildlife habitat losses and overall habitat 

fragmentation within the project area and surrounding region. 

4.7.7 Potential Monitoring and Mitigation

See Appendix K, Wildlife Monitoring and Protection Plan. 

4.8 Land Use

Land Use Impact Significance Criteria: Land use impacts would be significant if the project 

jeopardized current land uses or reclamation failed to achieve post-project land uses of rangeland, 

wildlife habitat and dispersed recreation. 

In the long-term, following natural gas extraction, the EIS analysis area would be used much as it 

is now. The reclamation and revegetation techniques to be undertaken on disturbed sites are 

comparatively simplistic, and commonly accepted techniques with a history of successful 

application in Wyoming and other western states. Reclamation would be initially employed 

concurrently for site stability and to lessen overall disturbance. Both interim and final reclamation 

would allow disturbed sites to return to conditions that existed prior to any disturbance. See 

Appendix F, Reclamation Plan. 

4.8.1 Effects of Alternative A (No Action)

Under the no action alternative, the land use of the EIS analysis area would not be disturbed by 

construction and production activities associated with the proposed action. Current land use 

trends in the region would continue, including coal mining, oil and gas exploration and 

development, electric power generation and transmission, grazing activities, and increased 

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Draft Environmental Impact Statement November 2005

recreational use. Pilot Project operations could continue, but disapproval of the entire build-out 

would probably cause cessation of such operations in the near-term. 

4.8.2 Effects Common to All Action Alternatives

Although oil and gas exploration and development activities have historically occurred within and 

adjacent to the EIS analysis area, the construction and operation of the proposed project would 

introduce a noticeable land use change within the immediate EIS analysis area. However, on a 

more regional basis, the Seminoe Road Project would not substantially change other land uses in 

Carbon County or on BLM-administered lands in south-central Wyoming. 

Disturbance would occur almost equally on both public and private lands. Approximately 4.5% of 

the 137,000-acre EIS analysis area would be disturbed with initial construction and drilling 

activities. With concurrent reclamation following drilling operations and installation (burial) of 

electric, water and gas utility lines, the area of total disturbance would be reduced to 1.7% of the 

137,000-acre EIS analysis area. See Table 2-1, Preliminary Estimate of Surface Area 

Disturbance. Upon project closure, these remaining disturbed areas would be reclaimed. 

A small portion of the EIS analysis area (approximately 3.2%) includes areas disturbed (mined) 

and reclaimed by coal mining companies. See Appendix E, Regional Activity; Figure 19, 

Regional Activity, Figure 44, Vegetation Map; and, Table 3.6-1, Vegetation Communities. 

Because coal mining companies maintain reclamation bonds of reclaimed lands with the 

Wyoming DEQ, Land Quality Division, any redisturbance of bonded mine reclaimed areas by 

Seminoe Road Project operations would require a transfer of reclamation success liability and 

responsibility from the coal mining company to the Proponent. 

Interim and final reclamation of surface disturbance is planned to re-establish wildlife habitat and 

livestock grazing. With mitigation and reclamation, the approval of any of the action alternatives 

would not substantially affect the long-term land use or land use planning on BLM-administered or 

adjacent private areas. 

The Seminoe Road Project would cause a short-term loss of rangeland, non-shrub wildlife habitat 

and dispersed recreation. Site access restrictions would continue to exist, primarily because of 

“checkerboard” land ownership patterns; disturbed sites would be restored as part of reclamation 

although re-establishment of shrub (sagebrush) habitat may take 15 to 20 years following 

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November 2005 Draft Environmental Impact Statement

reclamation. The short-term impacts would essentially be the same for all action alternatives, with 

very slight differences in the total number of acres disturbed. 

The main consequence effecting grazing management is the loss of available forage for livestock, 

as expressed in the short-term (0 to 10 years) and long-term (11 to 30 years). See Table 4.8-1, 

Grazing Allotment Impact Summary. AUMs lost are calculated by multiplying disturbed areas 

times the percent of allotment acres suitable for livestock grazing, then dividing by the allotment 

stocking rate on suitable lands. 

Table 4.8-1, Grazing Allotment Impact Summary 

Allotment Name 

Ft. Steele 

Breaks 

North 

Walcott 

Quealey 

Block Seminoe 

Horseshoe 

Ridge1 Totals 

Total Allotment Within EIS Analysis 

Area (acres) 5,300 41,400 5,850 75,000 100 127,6505 

Disturbance Within Allotment Short-term 

(acres)2 274 1,990 280 3,630 0 6,174 

Disturbance Within Allotment Long-term 

(acres)2 99 762 110 1,380 0 2,349 

Total Potential AUMs Within EIS 

Analysis Area3 221 1,375 415 5,260 5 7,276 

Lost AUMs – Short-term (0-10 years)4 11 66 20 252 0 349 

Lost AUMs – Long-term (10-30 years)4 4 25 7 95 0 131 

Notes: 

1. There would be no development on the Horseshoe Ridge allotment. 

2. Based on a short-term estimated disturbance of 4.5% and a long-term disturbance of 1.7% based on a total EIS 

area of 137,000 acres. (See Table 2-1, Preliminary Estimate of Surface Area Disturbance.) 

3. Based on AUMs/acre for each allotment (see Table 3.8-1, Allotment Summary). 

4. Based on AUMs/disturbed acre for each allotment. 

5. Acreage calculations for allotments within EIS analysis area indicates land area. An estimated 9,350 acres for 

the Seminoe Reservoir at the high water level within the EIS analysis area is not included in total. 

Source: BLM, 2004b. 

Minor impacts to roadside vegetation are anticipated as a result of dust generated along site 

roads within the EIS analysis and adjacent areas. Deposition of dust may result in the loss of vigor 

or plants because they would have reduced capability of photosynthesis as a result of lessened 

light availability. These effects are not considered substantial and would be minimized by 

proposed dust control measures (graveling of roads, speed limits). 

Project-related traffic, particularly during field development and drilling activities, would increase 

the potential for vehicle/livestock accidents. This potential would be greater in areas where calves 

and lambs are present. Traffic volume would decrease following development and drilling so 

vehicle/livestock collisions would be of less concern during field operations. 

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There is also a potential for damage to BLM and livestock operator fences, gates and cattle 

guards from the movement of trucks, drilling rigs and other heavy equipment and for the 

scattering of livestock off allotments and on to highways (Carbon County 351) from gates being 

left open. Unless gates, fences, or cattle guards are promptly repaired to appropriate standards, 

livestock may scatter off the allotment. Livestock scattering would result in additional costs for 

grazing permittees for locating and moving livestock and potential damage to the range outside of 

authorized allotments. 

Disturbance of soil and movement of vehicles would increase the potential for introduction and 

spreading of weed species. See Section 4.6, Vegetation. 

Reclamation objectives for all the action alternatives would be to return disturbed areas to a 

stabilized and productive condition and to protect and maintain the area’s land and water 

resources. Preliminary evaluations of the reclamation work at the Seminoe Road Pilot Project 

indicate that revegetation can be successfully accomplished. 

4.8.3 Effects of Alternative B (Proposed Action)

The impacts associated with Alternative B would be the same as those described in Section 4.8.2, 

Effects Common to All Action Alternatives. With proposed water discharges into drainages within 

the EIS analysis area, livestock would tend to congregate adjacent to flowing water or any ponds 

in the drainages. This activity would lead to concentrated livestock use, increased animal 

distribution, trampling of vegetation, and the potential for introduction and spread of weeds. 

Any erosion (head-cutting and side-cutting) of drainages caused by concentrated livestock use 

along water discharges (or by natural processes) could cause livestock to “trail” both sides of the 

drainages to locations where they can access water or cross the drainage. This natural process 

presently occurs in Pool Table Draw (where Pilot Project produced water is currently discharged) 

and in most of the drainages in the surrounding area. Pool Table Draw and other drainages have 

been incised by natural causes including heavy runoff from snow melt and summer 

thunderstorms. 

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4.8.4 Effects of Alternatives C (Pipeline to Reservoir) and D

(Underground Injection)

The impacts associated with Alternatives C and D would be the same as those described in 

Section 4.8.2, Effects Common to All Action Alternatives. There would be no water released in the 

draws and drainages of the EIS analysis area by either of these alternatives; therefore, no 

increased livestock trailing along drainages would occur. Under Alternative C, if a produced water 

pipeline is buried in the floodplain drainages, there would be a long term loss of sagebrush habitat 

in the stretch of area disturbed by produced water pipeline installation. 

4.8.5 Cumulative Impacts

No major cumulative land use effects are expected for any of the alternatives. Oil and gas 

development, coal mining, grazing, and recreation would remain the dominant land uses within 

and immediately adjacent to the EIS analysis area. 

4.8.6 Potential Monitoring and Mitigation

The BLM is responsible for issuing and managing leases that involve federal minerals and for 

specifying mitigation measures to protect surface resources as part of the APD approval process. 

4.9 Noise

Noise Impact Significance Criteria: Noise effects would be considered significant if activities 

exceeded 55 dBA at either human or animal sensitive locations. 

Noise has historically been recognized as a health hazard with the potential for causing hearing 

damage. Efforts by industry and regulatory actions have lessened the likelihood for hearing 

damage occurrence. OSHA imposes noise standards on industrial operations for worker hearing 

protection. 

A secondary impact associated with noise is the nuisance effects of noise that include 

interference with speech, psychologically unsettling environment at home and work, and more 

specific problems such as sleep disruption. The extent of these effects varies, sometimes 

significantly, between individuals and as a factor of the noise source. The noise characteristics 

which affect the listener’s response include overall loudness, sound pressure level, duration of 

exposure, time distribution of occurrence, and sound frequency. Other factors include the 

listener’s total exposure, age and individual susceptibility. 

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4.9.1 Effects of Alternative A (No Action)

Under the no action alternative, noise level from the propane-powered water pumps at the Pilot 

Project would continue, albeit in relatively isolated locations. Noise levels in the remainder of the 

EIS analysis area would continue at background levels, affected by wind speed and direction, 

traffic, recreational activities, nearby coal mining operations, and general rangeland management. 

Upon decommissioning and reclamation of the Pilot Project, the overall site would return to 

existing background noise levels. 

4.9.2 Effects Common to All Action Alternatives

Noise impacts associated with the Seminoe Road Project would be short-term and primarily occur 

during site development and construction activities, which include road building, well pad 

construction, utility installation and well drilling. Noise levels would essentially disappear after 

construction and drilling activities. Sources of operational noise would involve periodic vehicle trips 

to the well sites, noise from three compressors, and a few isolated, gas-powered, well-site pumps. 

Expected equipment and facility noise levels are presented in Table 4.9-1, Equipment Noise 

Levels. 

Table 4.9-1, Equipment Noise Levels 

Equipment dBA Range1 

Drills 85 - 90 

Loaders 75 – 85 

Backhoes 80 – 90 

Dozers 80 – 90 

Graders 80 – 85 

Compressors 80 – 90 gas powered2 

50 – 60 electric powered 

Well Pumps 70 – 80 gas powered 

40 – 50 electric powered 

Notes: 

1. As projected at 50 feet from source. 

2. If compressor is enclosed in a building, noise levels at 

50 feet would drop to 55 to 65 dBA. 

The inverse square law of noise propagation states that noise will decrease (attenuate) by 6 dBA 

for every doubling of distance. For example, if noise levels from a bulldozer measure 85 dBA at 50 

feet, the noise levels would be expected to drop to 79 dBA at 100 feet, 73 dBA at 200 feet, 67 dBA 

at 400 feet, 61 dBA at 800 feet, and 55 dBA at 1,600 feet. 

Not all construction equipment operates continuously or at full load, so the average noise level 

during well pad construction or during drilling is estimated to be approximately 85 dBA. Using the 

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November 2005 Draft Environmental Impact Statement

propagation formulation, average construction and drilling noise levels would decrease as set 

forth in Table 4.9-2, Noise Impacts Versus Distance. 

Table 4.9-2, Noise Impacts Versus Distance 

Distance From 

Source 

(feet) 

General Construction 

Noise 

(dBA) 

Well Pump Noise 

(Gas Powered) 

(dBA) 

Compressor Facility 

Gas Powered/Enclosed) 

(dBA) 

50 85 80 65 

100 79 74 59 

200 73 68 53 

400 67 62 47 

800 61 56 41 

1600 55 50 --

3200 49 44 --

Assuming well pad construction and/or drilling activities have average noise levels of 

approximately 85 dBA, it would be expected that noise levels would drop to near 55 dBA at 

approximately a quarter mile from the construction and/or drilling activities. 

Gas powered well pumps would drop to 55 dBA at approximately 900 feet from the well pad, while 

noise levels from electric-powered compressors (which are located in an enclosed building) would 

be negligible immediately outside the structure. 

Since the Boat Club is located over a mile north of the EIS analysis area, there would be no 

construction or operational noise from the Seminoe Road Project; before reaching the Boat Club, 

noise levels would attenuate to background levels given the distance. Conversely, during 

proposed road and drill pad construction and drilling activities, fishermen and other recreationists 

using the Coal Bay area would be subject to elevated noise levels. With completion of drilling and 

well installation, noise levels would return to existing background conditions. 

Recreationists and visitors to the Dugway Picnic area and Campground would be exposed to the 

noise from increased traffic on Seminoe Road (County Road 351). 

The effects of noise on wildlife is generally avoidance and accommodation. See Section 4.7, 

Wildlife/Fisheries. 

Indirect noise effects would result from additional non-work related trips made by new persons 

(workers and their families) that would move into Carbon County as a result of the Seminoe Road 

Project. This might include new workers hired for the project, workers hired to be employed for the 

service industries, or people simply looking for potential jobs associated with oil and gas activities. 

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This increase in activity would be minor and dispersed throughout Carbon County, primarily in the 

town of Rawlins. 

4.9.3 Effects of Alternatives B, C and D

The noise effects of Alternatives B, C and D would generally be the same as those described in 

Section 4.9.2, Effects Common to All Action Alternatives; however, gas-powered compressors 

would cause elevated noise levels surrounding the three compressor sites. 

4.9.4 Cumulative Impacts

Noise generated by the Seminoe Road Project would attenuate to near background noise levels 

within a relative short distance from its source. Overall noise on a cumulative basis would be 

negligible. Traffic noise would continue along the Seminoe Road (County Road 351) and from 

recreation users and visitors at Seminoe Road State Park and Reservoir. 

4.9.5 Potential Monitoring and Mitigation

If permanent residents become established in the Miller Bend development (Sections 17 and 18, 

T22N, R85W), the Proponent should conduct noise monitoring to obtain a more detailed 

understanding of noise impacts generated by construction and drilling activities, as well as for 

ongoing operational aspects. This survey work would provide additional site-specific data, but the 

overall conclusions from the additional survey work would probably confirm the EIS noise 

assessment. Specific noise mitigation could be implemented to lessen noise level impacts at 

residential receptors. This could include relocating the well pad access roads near the Miller Bend 

development, as well as providing additional noise control measures for construction, drilling, and 

operations. 

4.10 Cultural Resources

Cultural Resource Impact Significance Criteria: Cultural resource impacts would be 

considered significant if project development or activities result in adverse effects to properties 

listed or determined eligible for listing on the NRHP or considered important to Native American 

groups. 

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4.10.1 Effects of Alternative A (No Action)

Under the no action alternative, both known or undiscovered cultural resources would continue to 

exist in their present state. There would be no project-related surface disturbances beyond those 

currently permitted for the Pilot Project. Cultural resources would continue to be exposed to 

natural geomorphic processes or other disturbances associated with coal mining, oil and gas 

exploration and production, residential development and ranch management. 

4.10.2 Effects Common to All Action Alternatives

During each phase of the planned development of the Seminoe Road Project, the Proponent 

would construct access roads and drill pads and install utility lines (gas, water and electricity). This 

development would have the potential to affect cultural resources. As described in detail in 

Chapter 2 under Alternative B, the Seminoe Road Project would be developed in distinct 

development phases. Each phase of the project would be permitted by the BLM under APD permit 

regulations, and NEPA compliance (environmental assessment) would be needed for each APD. 

Prior to any development, i.e. construction of each phase of the project, cultural resources 

surveys would be conducted for any areas planned to be disturbed by project construction 

including roads, drill pads, compressor sites, ROWs, water discharge points, etc. Any cultural 

resource sites discovered during the surveys, would be identified as well as evaluated based on 

practices as outlined in Appendix M, Cultural Resource Management Plan. 

Prior to any project disturbance, Class III cultural field surveys must be conducted. Identification, 

evaluation and recording of any cultural resources would follow BLM cultural resource 

management guidelines as described in Appendix M, Cultural Resource Management Plan. 

The BLM operates under procedures promulgated under NHPA, 36 CFR 800, and/or the National 

Programmatic Agreement and Statewide Protocol to assess effects to sites deemed eligible for 

nomination to the NRHP. Significant adverse affects to cultural resources within the Seminoe 

Road Project analysis area would include: 

(1)	 Destruction or alteration to all or part of a property; 

(2)	 Isolation of a cultural resource from or alteration of, its surrounding environment; 

(3)	 Introduction of visual, audio or atmospheric elements that are out of character with the 

property or alter its setting; and, 

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(4)	 Neglect and subsequent deterioration. 

The BLM prefers to avoid disturbance to cultural resources and employ mitigation measures only 

if a site cannot be avoided. 

In the event an unanticipated discovery is made during the construction or operational activities, 

the following procedures will be employed: 

(1)	 Disturbance activities in the immediate vicinity of the discovery would be halted; 

(2)	 The BLM Rawlins Field Office Area Manager would be contacted; 

(3)	 A qualified BLM and/or Proponent-designated archaeologist would evaluate the site 

discovery. The BLM would be responsible for notifying Native American representatives, if 

necessary, for the particular discovery; and, 

(4)	 Mitigation measures would be employed at the site, which could include total avoidance, 

redesign of the development activities, or other measures as required by the BLM. 

4.10.3 Effects of Alternatives B, C and D

The impacts associated with Alternatives B, C and D would be similar to those discussed in 

Section 4.10.2, Effects Common to All Action Alternatives. 

4.10.4 Cumulative Effects

Oil and gas exploration and development, coal mining, recreational activities, livestock grazing 

and residential development could cause continued use and impacts to the region. This increased 

activity could cause impacts to cultural resources 

4.10.5 Native American Consultation

Pursuant to the NEPA, NHPA, the Federal Land Policy and Management Act, the American Indian 

Religious Freedom Act, and Executive Order 13084, the BLM has engaged in consultation talks 

with Native American representatives for the EIS development process. As part of the formal EIS 

scoping process in 2003, the BLM mailed letters, which requested input on any issues and 

concerns resulting from the proposed Seminoe Road Project, to the following Native American 

tribes: Eastern Shoshone, Northern Arapaho, Northern Ute, Northern Cheyenne, Ogallala Sioux, 

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November 2005 Draft Environmental Impact Statement

Rosebud Sioux, Shosone-Bannock, Crow, Comanche, Ute Mountain Ute, Uinta-Ouray Ute, and 

Southern Ute. 

Only one comment was received during the formal EIS scoping process, that from the Southern 

Ute Tribe, which stated: “There are no known impacts to areas of Native American cultural sites 

that are sensitive to this (Southern Ute Indian) tribe in regards to the Seminoe Road Project.” 

Subsequent to the scoping process, the BLM mailed follow-up letters in 2004, again seeking input 

on the project, to the Native American tribes listed in the previous paragraph, plus the Cheyenne 

River Sioux. These 2004 letters offered meetings and tours of the project site. 

The BLM will continue the Native American consultation process, as appropriate, throughout the 

completion of the EIS. No specific Native American sensitive sites (Native American Sacred Sites, 

TCPs) or issues have been identified by the tribes for the EIS analysis area; however, potentially 

sensitive sites such as burials, Native American cairns, and stone circle sites are known to occur 

in the region. The BLM plans to correspond with aforementioned Native American tribes prior to 

the implementation of each phase of the proposed project. As necessary or when requested, the 

BLM would meet with any interested tribe and conduct a tour of the planned development areas. 

4.10.6 Potential Monitoring and Mitigation

See Appendix M, Cultural Resources Management Plan. 

4.11 Recreation

Recreation Impact Significance Criteria: Recreation impacts would be considered significant if 

the project resulted in elimination or displacement of recreation activities for more than one 

season of use. 

4.11.1 Effects of Alternative A (No Action)

Under the no action alternative, recreational activity in the area (hunting, fishing, boating, 

camping, wildlife viewing, sightseeing, etc.) would continue, but the region is expected to 

experience increased recreational visitation. Current land use trends would also continue, 

including oil and gas development, coal mining and grazing, and these activities could 

incrementally degrade dispersed recreational opportunities, especially for certain visitors who 

seek solitude. 

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4.11.2 Effects Common to All Action Alternatives

Construction, drilling and production activities would have no impacts on developed recreational 

facilities (such as the Seminoe State Park and Dugway Recreation Site) and only minimal effects 

on dispersed recreation within the EIS analysis area, due to the checkerboard land ownership 

patterns within the EIS analysis area. Access to private lands is limited to those who obtain 

permission from the private landowners. Recreationalists can only access and use the few BLMadministered lands where legal public access is available. 

Hunting would be the primary dispersed recreation activity that would be directly affected by the 

project; this effect would result from wildlife avoidance in the immediate vicinity of construction 

and drilling activities. 

Recreation users traveling through the EIS analysis area on Carbon County Road 351 in route to 

the Seminoe State Park or Miracle Mile area would be subject to increased traffic on Carbon 

County Road 351 and to the visual impact of equipment and crews during construction and drilling 

periods, and to a lesser extent during actual production activities. The presence of equipment and 

crews may affect a user’s recreational experience, with noise levels and elevated traffic, which 

could increase the possibility of an accident (construction and drilling traffic merging onto Carbon 

County Road 351, trouble in passing, increased speed). 

During 2 or 3 years of construction and drilling in this area, fishermen and boaters on Seminoe 

Reservoir adjacent to the EIS analysis area and on Coal Creek Bay could be affected by the 

noise, dust, and visual intrusions caused by construction and drilling equipment and activities. 

Visitors to Seminoe Reservoir and Coal Creek Bay would not be displaced from the entire 

reservoir, but they may chose to go to other parts of the reservoir while construction and drilling is 

underway in the vicinity of Coal Creek Bay. 

As described in Appendix A, Proponents Project Description, the project would be completed 

in phases generally expanding to the south. Once construction and drilling activities are completed 

in a particular phase, the only residual activity would be routine operations and maintenance 

activities thus reducing any noise, dust, and visual impacts. During operations, the physical 

presence of roads, drill pads and compressor sites would remain, thus making the area less 

desirable for recreation than before the project. 

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The visual impacts associated with natural gas construction and production activities affect the 

aesthetic quality of the recreational experience. Such impacts would be considered substantial in 

VRM Class II areas until reclamation is successful, but the same impacts would be considered 

minimal in VRM Class III areas. See Section 4.13, Visual Resources and Figure 48, Visual 

Resource Management. Interim and final reclamation work would allow disturbed sites to 

eventually blend into the natural surroundings once revegetation is successful. 

Recreation visitors traveling on Carbon County Road 351 from Sinclair would experience 

increased traffic (see Section 4.12, Transportation) and would view construction and production 

activities as they pass through the EIS analysis area (see Section 4.13, Visual Resources). 

Production operations and maintenance would have little effect on recreation resources or 

opportunities in the region, since such activities would be relatively infrequent, primarily be 

adjacent to Carbon County Road 351 and would be located primarily in areas without legal public 

access. 

Recreationists at the developed campgrounds of Seminoe State Park and Dugway Recreation 

Site would not hear any project-related noise. If visitors, such as hunters or boaters on Seminoe 

Reservoir (particularly in Coal Creek Bay), pass through the EIS analysis area, they might hear 

project-related noise; however, such noise levels are expected to be low (see Section 4.9, Noise). 

There would be no direct impact to visitors or individuals fishing at the Miracle Mile section of the 

North Platte River, which is located 10 miles north of the EIS analysis area. 

Indirect effects to recreational resources could result from Seminoe Road project-related 

population increases in Carbon County. All of the action alternatives would require a temporary 

workforce during construction, some of which would migrate to the area. Given the current 

availability of housing in Rawlins and other communities in Carbon County, these temporary 

workers should not place pressure on local recreation facilities. Project workers would not be 

allowed to camp during the week on BLM lands or recreation sites. 

Project-related population growth could, however, increase demand on recreation resources in the 

area, especially the developed recreation facilities at Seminoe State Park and at Miracle Mile. 

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Draft Environmental Impact Statement November 2005

4.11.3 Effects of Alternatives B, C and D

The impacts associated with Alternatives B, C and D would be similar to those discussed in 

Section 4.11.2, Effects Common to All Action Alternatives. However, Alternative C might generate 

a noticeable increase in noise from gas-powered facilities, which could affect the recreation 

experience within and adjacent to the EIS analysis area. 

4.11.4 Cumulative Impacts

Cumulative impacts on recreational resources would result from the combined effects of normal 

increase in recreational demand in the region and the increased intensity of other land use 

practices. Current land use practices that could contribute to cumulative impacts to recreation 

would include oil and gas exploration and development, coal mining and grazing activities. 

With regional increases in employment from oil and gas development and increased use of the 

region by people from distant population centers such as the Denver/Front Range, developed 

recreational sites at Seminoe State Park and at the Miracle Mile would be expected to experience 

increased use. Since undeveloped and dispersed recreational use within the EIS analysis area is 

limited by the checkerboard ownership pattern, such dispersed undeveloped recreational use 

would not be expected to increase in the future, unless landowners choose to allow increased 

access to their private lands. 

4.11.5 Potential Monitoring And Mitigation

The Seminoe Road Project would comply with U.S. Bureau of Reclamation buffer zones from the 

Seminoe Reservoir (i.e., well pads and roads are required to be at least 500 feet from the 

Seminoe Reservoir high water line unless exemptions are granted). Exemptions would be 

required for Alternative C for the installation of produced water pipeline facilities adjacent to the 

high water line of the Seminoe Reservoir. 

4.12 Transportation

Transportation Impact Significance Criteria: Transportation impacts would be significant if: 

� Public highways were unable to handle project-related traffic levels; 

� Project-related traffic would cause measurable increases in accident rates or greatly 

increase the risk to highway users; or, 

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� Project roads did not comply with BLM road construction regulations. 

ADT is defined as the measure of traffic over a 24-hour period and is determined by counting the 

number of vehicles passing a specific point from both directions on a given road. 

4.12.1 Effects of Alternative A (No Action)

Under the no action alternative, no project build-out would occur, and no well pad access road 

network would be constructed. Existing two-track roads would continue to experience traffic for 

ranch management activities and dispersed recreational activities, such as hunting. 

Traffic patterns and volumes on Carbon County Road 351 and other highways in Carbon County 

would continue, and current land use trends in the area would also continue, including expected 

increased recreational activity such as hunting, boating, fishing and camping. This activity would 

cause additional traffic on Carbon County Road 351, but this road has been recently improved 

within and immediately outside of the EIS analysis area (see Section 3.12, Transportation), so any 

added traffic volume associated with recreational use would not effect the integrity of this road. 

Under the no action alternative, the Proponent’s activities at the Pilot Project could continue under 

existing permits and approvals until the Proponent decides to close and reclaim the project. Pilot 

Project final reclamation would probably take place in the summer and related increased in traffic 

for such reclamation work would be minimal and short-term. 

4.12.2 Effects Common to All Action Alternatives

If an action alternative is selected, direct effects to the existing transportation network, especially 

Carbon County Road 351, would result from an increase in daily traffic to the EIS analysis area. 

This would result from employee related traffic combined with drilling equipment, supply and 

material transport. 

With all proposed action alternatives, there are three separate phases: 

� Construction and drilling; 

� Operations and production; and, 

� Final reclamation. 

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The construction and drilling phase for all action alternatives would last approximately 10 years 

and would have the largest impact to traffic loads. Supply trucks, gravel trucks and pickup trucks 

associated with construction and drilling would cause an increase of approximately 110 trips per 

day to the EIS analysis area. For the first 5 years, the main access to the project would be via 

County Road 351. Traffic levels would increase by 50% on this road during this time period. Drill 

rigs and heavy equipment used to construct roads and well pads would be transported to the site 

and would typically remain on site until construction and drilling activities are completed. 

Construction and drilling traffic would peak during the summer and fall construction seasons, then 

decline during the winter and spring months. 

Operational and production traffic would require approximately 40 trips per day. This traffic would 

mainly be pickup trucks for operational and maintenance personnel required on site. Periodically, 

work-over drill rigs and associated equipment would be required for refurbishing wells; this traffic 

would occur sporadically during the operational and production phase of the project. There would 

be operation and production traffic through the first 10 years of the project. During the final 10 to 

20 years of operation, traffic would consist primarily of operation and maintenance personnel. 

Upon cessation of gas production from the site, final reclamation activities would commence. It is 

anticipated that final reclamation activities would require 2 years, with most reclamation occurring 

during summer and fall months. Final reclamation would experience a peak traffic load of 

approximately 40 trips per day to the project site. Heavy equipment used for final reclamation 

would be transported to the site at the beginning of each season and would probably remain until 

reclamation activities are complete. 

The following aspects of the Carbon County transportation network would be affected by 

employee, supply and equipment transport to the EIS analysis area: 

� Public Access, 

� Traffic Load, 

� Public Safety, 

� Environmental Safety, and 

� Road Maintenance. 

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4.12.2.1 Public Access

Under all action alternatives, public access into the “working” sites of the EIS analysis area would 

be restricted. Access from Carbon County Road 351 would be located on private surface such 

that access points could be gated. In addition, access north of the Union Pacific Railroad line in 

Section 26, T21N, R84W would similarly be restricted. Access in the ROW of the WAPA 69 kV 

electric transmission line would be limited to “perpendicular” crossings. Unless otherwise needed 

for some long-term land use (i.e., WAPA 69 kV line and Conoco pipeline maintenance) or 

requested by the private landowners, access roads throughout the EIS analysis area would be 

reclaimed following completion of natural gas extraction. 

4.12.2.2 Traffic Load

Existing traffic loads for County Road 351, State Highway 30/287, and I-80 are set forth in Section 

3.12, Transportation. 

County Road 351. During the first 5 years of the project, construction and drilling traffic would 

access the project site via County Road 351 and cause an estimated 50% increase in traffic over 

current traffic levels. Much of the traffic would include tractor-trailer rigs and gravel trucks. 

However, because County Road 351 has recently been upgraded, the additional traffic should not 

result in any major increased maintenance costs for the road. 

Following construction and drilling activities, project-related traffic loads on Carbon County 351 

would decline. Ongoing operations and production traffic would be approximately 25% higher than 

2002/2003 traffic levels. 

State Highway 30/287. For construction and drilling activities south of Seminoe Reservoir and 

the North Platte River, traffic would access the site via Walcott Junction on I-80 east of Sinclair, 

utilize State Highway 30/287 for approximately one-quarter mile, then use an existing gravel road 

north into the project site. Construction and drilling traffic on State Highway 30/287 would be 

approximately 20% above current levels; and, similar to traffic on Carbon County Road 351, 

operations, production and reclamation traffic would decrease but still be approximately 5% above 

2002 and 2003 levels. 

Interstate 80. Given the large current traffic load on I-80 in the vicinity of Rawlins and Sinclair, 

any traffic volume created by Seminoe Road Project activities would be minimal on I-80. Even at 

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peak construction and drilling periods, project related traffic on I-80 would be less than 1% of the 

total traffic loads. 

Internal Project Roads. Although there are an estimated 300 miles of existing, two-track roads 

criss-crossing throughout the EIS analysis area, these roads are subject to minimal traffic, 

principally traffic associated with ranch management activities. Approximately 200 miles of 

existing roads and 270 miles of new roads would be needed for the Seminoe Road Project. These 

roads would be constructed to provide year-round access, with gravel surfacing, and they would 

be maintained throughout the life of the project. The existing two-track roads would require 

upgrading. See Figure 4, General Layout Map, for projected project road locations. 

4.12.2.3 Public Safety

Accident statistics were collected for Carbon County Road 351 and I-80 (Walcott Junction to 

Rawlins) from the Wyoming Department of Transportation. The data were collected for 1999 

through 2003. A summary of the data is presented on Table 4.12-1, Accident Data: Carbon 

County Road 351 (1999-2003) and Table 4.12-2, Accident Data: Interstate 80 Walcott to 

Rawlins (1999-2003). 

Table 4.12-1, Accident Data: Carbon County Road 351 (1999-2003) 

Year Number Persons 

Injured 

Number Persons 

Killed 

Crashes Involving 

Property Damage 

Only 

Injury 

Crashes 

Fatal 

Crashes 

Total 

Crashes 

1999 0 0 6 0 0 6 

2000 4 0 9 2 0 11 

2001 0 0 6 0 0 6 

2002 9 0 3 4 0 7 

2003 6 0 2 4 0 6 

Total 19 0 26 10 0 36 

Source: Wyoming Department of Transportation (2004) 

Table 4.12-2, Accident Data: Interstate 80 Walcott to Rawlins (1999-2003) 

Year Number Persons 

Injured 

Number Persons 

Killed 

Crashes Involving 

Property Damage 

Only 

Injury 

Crashes 

Fatal 

Crashes 

Total 

Crashes 

1999 64 10 77 34 5 116 

2000 48 0 83 32 0 115 

2001 56 3 69 29 2 100 

2002 49 2 62 2 2 92 

2003 88 3 82 45 2 129 

Total 305 18 373 168 11 552 

Source: Wyoming Department of Transportation (2004) 

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The data for Carbon County Road 351 reveals that there were 36 accidents from 1999 through 

2003. Of these, 18% were alcohol and speed related, 18% due to bad weather, 41% caused by 

animal-vehicle collisions, and the remaining 23% due to miscellaneous factors including driver 

fatigue. There were no fatalities on Carbon County Road 351 from 1999 through 2003. 

A reported 552 accidents occurred on I-80 between Walcott Junction and Rawlins from 1999 

through 2003. There were eleven fatal accidents with a total of 18 fatalities. Winter weather 

conditions were a factor in 58% of the accidents, with only 5% involving animal-vehicle collisions. 

With the expected increase in traffic and the transport of equipment and supplies to the EIS 

analysis area, there is a potential for accidents involving employees or the supplies and 

equipment hauled to the site. 

4.12.2.4 Environmental Safety

Diesel fuel would be the principal supply transported to the EIS analysis area. Whenever and 

wherever diesel, propane, or other dangerous or environmentally hazardous materials are 

transported, there is a potential for an accidental spill. These materials would be transported to 

the project site in conformance with U.S. and Wyoming Departments of Transportation 

regulations. Spill prevention would be an important objective during transportation of such 

materials. Areas approximate to the North Platte River and the various intermittent/ephemeral 

streams within the EIS analysis area would be susceptible to degradation if an accident resulting 

in a spill occurred. 

4.12.2.5 Road Maintenance

Given projected traffic loads, coupled with the existing conditions of Carbon County Road 351, 

State Highway 30/287, and I-80, minimal additional maintenance would be required on these 

roads for the life of the project. These roads have the surfacing, grade and width to handle any 

project-related traffic. State and county maintenance departments are responsible for any regular 

road maintenance and snow removal. It is expected that there would be times during extreme 

snowstorms or blizzard conditions when these state and county roads would be closed to traffic. 

Internal project roads, however, would require routine maintenance throughout the life of the 

project. Such maintenance measures would include grading, watering or other dust controls, 

resurfacing with gravel, and snowplowing in winter months. Since there is expected to be no or 

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negligible public use of these access roads, such maintenance requirements, including 

snowplowing, would be the responsibility of the Proponent. 

4.12.2.6 Indirect Effects

Indirect effects to the Carbon County transportation network would result from additional non-work 

related trips made by new persons (workers and their families) that would move into the region as 

a result of the Seminoe Road Project. The projected number of new workers is expected to be 

minimal (see Section 4.14, Socioeconomics). Any increase in traffic would probably be dispersed 

throughout Carbon County. It would not be concentrated in the vicinity of the EIS analysis area. 

Therefore, this traffic would be only a minor component in the cumulative impacts on any roads 

near the project site. 

4.12.3 Effects of Alternatives B, C and D

The impacts associated with Alternatives B, C and D would be the same or very similar to those 

discussed in Section 4.12.2, Direct Effects Common to All Action Alternatives. 

4.12.4 Cumulative Impacts

Project traffic combined with traffic associated with future recreational and other land use 

activities, particularly on Carbon County Road 351 would result in some cumulative effects and 

could add to the possibility of accidents. However, even with the projected traffic volumes 

associated with the Seminoe Road Project and surrounding future activities, it is not expected that 

such activities would affect the operational conditions of Carbon County Road 351, State Highway 

30/287 or I-80. 

4.12.5 Potential Monitoring and Mitigation

No additional mitigation beyond that discussed in Section 2.8.7, Road Construction/Transportation 

would be needed for the project. 

4.13 Visual Resources

Visual Resources Impact Significance Criteria: Visual impacts would be considered significant 

if there was long-term non-compliance with the RMP designations for visual resources within the 

project area (VRM Class II and III). 

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The visual resource analysis is based on the premise that many travelers on County Road 351 (a 

BLM-designated National Back Country Byway) and visitors who recreate on Seminoe Reservoir 

and at Miracle Mile would prefer to see the landscape in a condition as close as possible to its 

natural state. Approximately 55% of the EIS analysis area designated as a VRM Class II area, and 

the BLM manages Class II area so any development is as compatible as possible with the 

landscape’s natural form, line, color and texture. 

The severity of a visual effect is dependent upon a number of factors including: 

� The capability of the surrounding landscape to integrate visual changes without attracting 

attention; 

� The distance from sensitive viewing areas; 

� The level of disturbance to the visual resource; and/or, 

� Reclamation potential of disturbed landscapes. 

The duration of the impact would be a function of both the time to complete the action and the 

time to return the disturbed area to a pre-disturbance condition. In general, the visual impact 

would be greatest where visual contrast exists and revegetation would be slow to restore the 

landscape to pre-project vegetative conditions (such as in sagebrush communities where mature 

sagebrush revegetation may take 20 years after reclamation to blend with surrounding 

undisturbed areas). 

As indicated in Section 3.13, the EIS analysis area contains BLM VRM Class II and III areas. See 

Figure 48, Visual Resource Management. The Class II areas, which constitute over half (55%) 

of the EIS analysis area allow only minor changes to the existing landscape, and these areas are 

visible to travelers along County Road 351 and by recreationists who visit Seminoe Reservoir and 

the North Platte River. The remainder of the EIS analysis area, including the lands adjacent to 

Carbon County Road 351 are VRM Class III areas, which allow for moderate changes to the 

existing landscape. 

A viewer would judge visual impacts of natural gas development and production activities from a 

perspective of foreground, middleground and background. These terms are defined as follows: 

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Foreground – generally the area that lies within one-half mile of the viewer; 

Middleground – the area between the foreground and background in a landscape, typically 

from 1/2 mile to 5 miles from the viewer; and, 

Background – the distant part of a landscape located beyond 5 miles from the viewer. 

4.13.1 Effects of Alternative A (No Action)

Under the no action alternative, visual contrasts would remain in their current state and, other than 

the localized visual effects created by the Pilot Project, the overall viewshed in the EIS analysis 

area would not be disturbed. 

The Pilot Project would continue under the terms of its previous approval, but upon cessation of 

this activity, the disturbed areas would be reclaimed. For the near term, signs of Pilot Project 

operations would be visible to those passing through the immediate area. However, following 

reclamation and as vegetation becomes established, the disturbed areas would blend into the 

surrounding landscape. 

The area’s visual character would continue to be affected by existing facilities, such as the WAPA 

69kV electric transmission line and Carbon County Road 351. Seminoe Reservoir and its 

fluctuating shoreline would remain visible. In the southern portion of the EIS analysis area, the 

communications tower in Section 31, T22N, R84W, would be visible from I-80 near Walcott. Coal 

mining operations and reclamation activities would also remain visible within and adjacent to the 

southeast portion of the EIS analysis area. 

4.13.2 Effects Common to All Action Alternatives

All action alternatives would present short-term visual contrasts between the industrial character 

of construction and drilling equipment and surrounding natural landscape. Roads constructed and 

used to access well pad sites would present distinct linear contrasts with the existing natural 

landscape’s colors and textures. 

Regardless of the direction of travel on County Road 351, surface disturbance (roads and well 

pads) within the EIS analysis area would be visible from both a foreground and middleground 

perspective. The compressor sites would be generally hidden from view for travelers on Carbon 

County Road 351; these facilities would be located in lower areas or behind low ridgelines to hide 

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them. The perspective of background for viewers traveling north on Carbon County Road 351 

through the EIS analysis area would be dominated by the Seminoe Mountains located north of the 

project area, while the south-looking view from a background perspective would be dominated by 

Elk Mountain to the southeast and the ridgeline (Cedar Ridge) that forms the southwest boundary 

of the EIS analysis area. Recreationists, hiking the ridges of the Seminoe Mountains would see 

the road network within the project area. However, the view would be from nearly 10 miles away, 

which would tend to diminish the visual effects. 

Mitigation measures set forth in Section 2.8.21, Visual Resources, would minimize the visual 

impacts of construction and production activities from Carbon County Road 351. As a result, the 

proposed Seminoe Road Project would not violate the VRM Class II and III direction for the area 

or produce contrasts beyond the degree allowed for in VRM guidelines from a middleground or 

background perspective. From a foreground perspective, surface disturbance and non-blending 

facility coloration may attract viewer attention, thus exceeding the Class II VRM objective in some 

locations. 

Approximately 5 miles of County Road 351 in the EIS analysis area traverses lands designated by 

the BLM as VRM Class II. Travelers on this stretch of road would be able to observe construction 

and drilling activities. The masts of the drill rigs would be particularly noticeable on each side of 

the roadway, although actual drilling time for each well would be minimal, averaging one to two 

weeks. Following well development and interim reclamation, well site facilities (well head and 

gas/water separator building) and well site access roads would remain visible, but mitigation and 

reclamation would cause well site facilities to blend with surrounding undisturbed areas. Sections 

of the project graveled access roads would remain visible from Country Road 351 throughout the 

project life. 

Because electric utility (power) lines to well pad sites would be buried, there would be no visual 

impacts associated with overhead powerlines, except for the 115kV 8,000-foot long feeder line 

that would provide electricity to the compressor site located in Section 10, T23N, R85W. The 

projected centerline for this feeder line is located in a VRM Class III area and is shown on Figure 

4, General Layout Map. 

Boaters on Seminoe Reservoir would generally be screened for direct viewing of project well pads 

and roads by topography. The lower the water level, the less likely that boaters would be to view 

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construction and production activity. In addition, the U.S. Bureau of Reclamation regulates 

construction activities within 500 feet of the high water mark of the Seminoe Reservoir. 

Drill rig lights would be visible from Carbon County Road 351 at night, depending on the type, 

intensity, location of lighting used, and on weather conditions. Given the remoteness of the EIS 

analysis area and the concentrated nature of the drilling activity, this lighting is not expected to 

impact the general nighttime scenic quality of the area for campers and stargazers. Similarly, 

lighting from production facilities, such as compressor facilities, would not affect nighttime scenic 

quality. 

4.13.3 Effects of Alternatives B, C and D

The visual effects of Alternatives B, C and D would be the same as those described in Section 

4.13.2, Direct Effects Common to All Action Alternatives, except that the increase in the scope of 

the project would cause visual impacts to be apparent over a greataer acreage, thereby 

increasing the probability that development would exceed Class II VRM objectives. 

4.13.4 Cumulative Impacts

Roads, the Conoco pipeline, the WAPA 69 kV electric transmission line, coal mining and the 

Seminoe Reservoir have permanently altered the scenery of the EIS analysis area. The visual 

effects of these developments would continue into the foreseeable future. 

4.13.5 Potential Monitoring and Mitigation

To avoid unacceptable visual impacts that would exceed BLM VRM objectives, mitigation would 

be employed for the permanent structures (facilities onsite for 6 months or longer) including 

pumping units, well-site separator buildings, compressor housings, water treatment tanks, roads, 

etc. Roads must be planned and sited to minimize visibility from Carbon County Road 351, 

especially in Class II VRM areas. 

4.14 Socioeconomics

Socioeconomic Impact Significance Criteria: Socioeconomic impacts would be significant if: 

� An increase in county or community population would strain the ability of Rawlins to 

provide housing and services or otherwise adapt to growth related social and economic 

changes; or, 

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November 2005 Draft Environmental Impact Statement

� An aggregate change in revenue and expenditure flows would cause Carbon County or 

the town of Rawlins to be unable to maintain public services and facilities at established 

service levels. 

The socioeconomic effects discussed in this section consider information presented in Section 

3.14, Socioeconomics. In addition, projections regarding the Proponent’s project description 

(Appendix A, Proponent’s Project Description) and specifically the workforce projections made 

in Section 2.4.11, Workforce, were used for the impact analysis. 

Direct and indirect socioeconomic impacts are evaluated for Carbon County. Fiscal effects are 

evaluated primarily in terms of direct consequences, as indirect effects are less readily quantified. 

Cumulative impacts are discussed in the context of other activities occurring in Carbon County. 

See Appendix E, Regional Activity. 

Whenever possible, socioeconomic effects are identified in quantitative or numerical terms (such 

as number of jobs, housing units or school students). Some impacts (such as effects on social 

values) are more difficult to evaluate numerically and so are described primarily in a qualitative or 

narrative manner. 

All of the action alternatives would have socioeconomic effects, including increased employment 

and additional federal, state and local government tax revenues. Statistical measures such as 

population, school enrollments, housing and community and public services would not be 

significantly affected by the Seminoe Road Project as Carbon County (and in particular the town 

of Rawlins) already has the general infrastructure necessary to support the proposed employment 

at the project. 

Many of the socioeconomic effects can be assessed from an historic perspective. Oil and gas 

exploration, development and production in south-central Wyoming have been cyclical rather than 

constant. Further, the “boom” cycle created by coal mining in Carbon County during the late 1970s 

and early 1980s created peak population, employment, and general socioeconomics to which 

Carbon County has not yet recovered. The projected pace of development and production from 

the Seminoe Road Project would not cause any dramatic influx of population or employment. To a 

great extent, many persons already living within Carbon County would be afforded opportunities 

for employment at the Seminoe Road Project. 

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4.14.1 Effects of Alternative A (No Action)

Under the no action alternative, the EIS analysis area would remain undeveloped. Selection of the 

no action alternative would forgo an opportunity for increased economic activity and income for 

Carbon County and Wyoming. Pilot Project operations could continue, but disapproval of the 

entire build-out would probably cause cessation of such operations in the near-term. 

4.14.2 Effects Common to All Action Alternatives

There would be little variation in the socioeconomic effects among action alternatives: the primary 

differences in the alternatives relate to physical design and operation. The effects for all action 

alternatives are discussed for the following aspects: 

� Employment 

� Income 

� Population 

� Housing 

� Community and Public Services 

� Fiscal Conditions 

� Social Values 

4.14.2.1 Employment

All of the action alternatives would result in increased employment in Carbon County. Both direct 

and indirect employment estimates are based on assumptions as outlined in Table 4.14-1, 

Employment Assumptions. 

The proposed construction and drilling activities are scheduled to take place in phases over a 

period of 10 years. Actual gas production would follow construction and drilling activities and is 

projected to last over a 30-year period. Employment would be scaled back as production ceases 

and final reclamation activities begin. 

Each phase of the Seminoe Road Project would involve a different workforce component. The 

construction and drilling workforce would be composed of many different categories of 

occupations including drillers, driller helpers, heavy equipment operators, truck drivers and 

miscellaneous support laborers. In addition, carpenters, electricians and pipe fitters would be 

employed to complete specialized tasks. 

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November 2005 Draft Environmental Impact Statement

Table 4.14-1, Employment Assumptions 

Category Years 

1 – 2 3 – 4 5 – 9 10 – 30 31 - 32 

Direct Employment

1 

Construction & Drilling 60 60 60 -- --

Operations 20 35 50 50 --

Closure & Reclamation -- -- -- -- 30 

Total Direct Employment 80 95 110 50 30 

Indirect Employment

2 64 76 88 40 24 

Total New Job Opportunities 144 171 198 90 54 

Notes: 

1. These direct employment numbers represent an estimate of annual job equivalents. Typically in Wyoming, oil 

and gas construction, development and operational employment rates are higher from July into December, 

and they are lower from late December to June because of wildlife concerns and weather (winter and 

springtime) conditions. These numbers are used to “annualize” employment. Like other Wyoming operations, 

the Seminoe Road Project would experience peak employment in the months between July and December, 

especially for drilling and construction activities where such related employment in years 1 – 9 could peak at 

over a hundred workers. 

2. Indirect employment refers to new jobs that would be created in the service, retail and non-gas related sectors 

to support the Seminoe Road Project and its workforce. For this analysis, an employment multiplier of 1.8 was 

used. The 1.8 multiplier means that for every 100 new basic jobs at the Seminoe Road Project, another 80 

service and retail jobs would be created in the local economy. 

The operational production phase of the Seminoe Road Project would require crews experienced 

in gas production, along with on-site supervisory personnel. Administration and maintenance 

personnel would also be employed during production. 

Reclamation would employ heavy equipment operators, construction personnel, and individuals 

experienced in reclamation. On-site management and reclamation specialists would also be 

involved during this period. 

New (indirect) jobs would be created in the service, retail and other non-gas related sectors of the 

local and regional economy to support the Seminoe Road Project and its workforce. A wide variety 

of employment multipliers are used to predict indirect employment. For purposes of this analysis, 

and employment multiplier of 1.8 was used. This means that for every new job created at the 

Seminoe Road Project, an estimated 0.8 support or service sector job would be created in Carbon 

County. This figure represents that some gas related service and retail jobs already exist in 

Carbon County (particularly in Rawlins); however, many oil and gas supporting industries are 

located outside of Carbon County. 

4.14.2.2 Income (Wages)

According to 2000 occupational employment and wage figures published by the Wyoming 

Department of Labor for Carbon County (see Section 3.14.5, Income), medium wage for oil and 

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Draft Environmental Impact Statement November 2005

gas workers within this County was approximately $46,000 per year. Similarly, annual wage for all 

occupations within Carbon County was approximately $25,000 per year. 

During the first 9 years of activity, which would include construction, drilling and production, payroll 

income from direct employment would range from an estimated $3.7 to $5.1 million per year. 

Following the completion of all drilling and construction activities in year 9, the payroll income from 

direct employment at the Seminoe Road operation for years 10 through 30 would average 

approximately $2.3 million per year. During closure and final reclamation activities (projected to be 

in years 31 and 32), payroll income as a result of direct employment would be approximately $1.4 

million per year. All of these estimates regarding payroll income for direct employment are based 

on 2000 Wyoming Department of Labor wage figures. 

Over the life of the entire Seminoe Road Project, total payroll from direct employment is estimated 

to reach approximately $925 million. See Table 4.14-2, Estimated Payroll Income. 

Table 4.14 2, Estimated Payroll Income1,2 

Payroll 

($ x 1,000,000) 

Years Total 1 – 2 3 – 4 5 – 9 10 – 30 31 - 32 

Construction/Drilling 5.52 5.52 13.80 -- -- 24.84 

Operations 1.84 3.22 11.50 48.30 -- 64.86 

Closure/Reclamation -- -- -- -- 2.76 2.76 

Direct Payroll Income3 7.36 8.74 25.30 48.30 2.76 92.46 

Indirect Payroll Income4 3.20 3.80 11.00 21.00 1.20 40.20 

Total Payroll Income5 10.56 12.54 36.30 69.30 3.96 132.66 

Notes: 

1. Payroll income estimates are based on employment assumptions set forth in Table 3.14-1, 

Employment Assumptions. 

2. 2000 dollars. 

3. Annual average 2000 wage for oil and gas workers in Carbon County, Wyoming estimated at $46,000 

based on Occupational Employment and Wage Figures from Wyoming Department of Labor. 

4. Annual mean 2000 wage for all occupations in Carbon County, Wyoming estimate at $25,000 based 

on Occupational Employment and Wage figures from Wyoming Department of Labor. 

5. Total payroll income = direct payroll income + indirect payroll income. 

During the life of the Seminoe Road Project, payroll income from indirect employment would 

average over $1 million annually. Indirect payroll would range from approximately $0.6 million 

during reclamation (years 31-32), to a peak of $2.2 million during the first 9 years of operation. 

Total payroll income for indirect employment over the life of the project would amount to $40.2 

million. 

Total direct and indirect payroll income for the life of the Seminoe Road Project is estimated to be 

$132.7 million. See Table 4.14-2, Estimated Payroll Income. 

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November 2005 Draft Environmental Impact Statement

4.14.2.3 Population

The Seminoe Road Project is not expected to significantly increase the population of Carbon 

County. See Table 4.14-3, Population Increase Potential. Even during the peak employment 

periods projected for years 5 through 9 of the project, the population of Carbon County would 

increase less than 1%. Assuming that all newcomers were to move into the town of Rawlins, the 

peak population growth for Rawlins itself would still be less than 2%. 

The projected population increases as a result of the Seminoe Road Project would not (by itself) 

reverse the projected declines in Carbon County population that are expected to occur over the 

next 20 years. See Table 4.14-3, Population Increase Potential. 

Table 4.14-3, Population Increase Potential 

Employment Category 

Peak Years 5 - 9 

Total Employment

1 Non-local Employment Population Growth 

Construction & Drilling 60 302 635 

Operations 50 103 266 

Indirect Jobs 88 224 537 

Total 198 62 142 

Notes: 

1. See Table 3.14-1, Employment Assumptions. 

2. Assumes 50% of employees from outside of Carbon County. 

3. Assumes 20% of employees from outside of Carbon County. 

4. Assumes 25% of employees from outside of Carbon County. 

5. Assumes 20% of non-local employees single; 40% with household size (rental-occupied for Rawlins of 

2.16); and 40% with household size (owner-occupied for Rawlins of 2.58). See Table 3.14-4, Average 

Household Size: 2000. 

6. Assumes 100% with household size of 2.58 for owner-occupied for Rawlins. See Table 3.14-4, 

Average Household Size: 2000. 

7. Assumes 50% split between those who rent and own, for household sizes for Rawlins. See Table 3.14­

4, Average Household Size: 2000. 

Changes in population from this proposal are driven by three factors: 

(1)	 The number of new (or non-local) employees transferred or recruited to the area by the 

Proponent; 

(2)	 The number of households and average household size associated with new


employees that become new residents; and


(3)	 The number of new (non-local) workers and their families drawn to the area in


industries that provide goods or services to those employed at the oil and gas


operations.


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Construction and drilling related jobs at the Seminoe Road Project would occur over a 9-year 

period; however, these jobs would not have a long-term impact on Carbon County population. 

Many drilling and construction workers generally do not bring their families to the area due to the 

relative short duration of construction activities, which occur mainly between July and November 

of any given year. About 50% of the construction workers are expected to be non-local, due to a 

need for specific task experienced workers who have experience in oil and gas field construction 

and drilling. 

For operations and production, an estimated 80% of the workforce would consist of local hires. 

This represents a fairly high rate of local hiring, but there are many people in Carbon County who 

have experience in the oil and gas industry and a portion of the construction and drilling 

employees that do move to the area may decide to stay and work permanently at the Seminoe 

Road Project. 

Local expenditures made directly for the Seminoe Road Project and by employees would result in 

an increased demand for goods and services in Carbon County. Some of this demand would be 

met by existing residents working in stores, real estate offices and other businesses. However, 

the new demands generated by the Seminoe Road Project (and other potential oil and gas 

projects in Carbon County) would be expected to draw new service providers and residents into 

the area, even though they are not directly connected with the Seminoe Road Project. Given the 

current relatively high availability of local labor force, it has been assumed that approximately 75% 

of the new indirect jobs would be taken by existing Carbon County residents. About 25% would 

involve non-local hires. 

The term “local hire” is intended to mean persons who have lived in Carbon County prior to hiring 

and who did not move into Carbon County in anticipation of being hired at the Seminoe Road 

Project. Employment used to characterize construction and drilling, operations and indirect 

employment are set forth in Table 4.14-3, Population Increase Potential. 

4.14.2.4 Housing

The Seminoe Road Project could create a potential long-term demand for 25 to 30 housing units 

(houses, apartments, mobile homes, etc.) with a potential peak of 60 units. This demand can be 

accommodated by existing housing resources, which report a vacancy rate of over 1,000 unit for 

sale or rent in Carbon County and nearly 500 units in Rawlins. See Table 3.14-3 Housing 

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November 2005 Draft Environmental Impact Statement

Profile: 2000. Even with a peak demand of 60 units, the Seminoe Road Project would only 

account for slightly more than 10% of the available housing supply in Rawlins. 

The Seminoe Road Project could also generate demand for temporary housing, particularly during 

the construction and drilling phases of the project. The town of Rawlins would be able to 

accommodate temporary housing needs, specifically for those individuals seeking hotel or motel 

rooms and recreational vehicle park spaces. Similarly, it is expected that workers seeking 

apartments, houses or mobile homes to rent could be accommodated by the available supply of 

such rental units in Rawlins and Carbon County. 

4.14.2.5 Community and Public Services

The Seminoe Road Project would not strain community facilities and public services in Carbon 

County, specifically in the town of Rawlins. As explained in Section 3.14.1, Population, the 

population levels in Carbon County, and specifically Rawlins, remain substantially below peak 

levels of the 1980s. Most public facilities were sized to accommodate larger populations and 

would be able to accommodate the relatively small population increment associated with the 

Seminoe Road Project. Further, the Seminoe Road Project is expected to generate substantial tax 

revenues, which could be used to fund any demand for community or public services created by 

direct or indirect employment and population as a result of the project. 

4.14.2.6 Fiscal Conditions

Over its projected 30-year life, the Seminoe Road Project would generate substantial tax 

revenues, including ad volorem property taxes on production and field facilities, Wyoming 

severance taxes, federal mineral royalties, Wyoming state mineral royalties, and sales and use 

taxes on materials, supplies and equipment used at the project site. In addition, drilling and 

construction, production and reclamation workers, combined with the indirect workforce created 

as a result of the project, would pay federal, state and local taxes. 

Assuming that the Seminoe Road Project produces 500 million cubic feet (mcf) of natural gas 

over its 30 year life (an average of approximately 16,700,000 mcf per year), the estimated 

revenues associated with this production, along with the costs associated with development, 

operation and reclamation are set forth in Table 4.14-4, Estimated Revenues and Costs. It is 

important to note that the estimated revenues and costs set forth for the Seminoe Road Project 

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Draft Environmental Impact Statement November 2005

are simply a “best guess” at this time. Actual revenues and costs could be substantially different 

as the Proponent gains actual field experience during project build-out. 

Table 4.14-4, Estimated Revenues and Costs 

TOTAL REVENUES $1,500,000,000 

500 million mcf @ $3/mcf at wellhead in Wyoming (mcf = thousand cubic feet: typical measure of 

gas production) 

CAPITAL AND DEVELOPMENT INVESTMENT $620,000,000 

(For project development, drilling, completion, gas gathering systems and field infrastructure) 

1,240 wells @ $500,000/well and associated infrastructure 

LABOR (DIRECT) $92,460,000 

(For construction and drilling, operations and production, closure and reclamation: See Table 

4.14-1, Employment Assumptions and Table 4.14-2, Estimated Payroll Income) 

LABOR (GENERAL OVERHEAD) $27,740,000 

(Includes costs for health and life insurance, retirement, vacation, FICA, unemployment, 

workman’s compensation, training, etc. – assume 30% of direct labor costs) 

DEVELOPMENT. OPERATIONAL & RECLAMATION EXPENDITURES $155,000,000 

(For ongoing expenditures such as fees, general site costs, contract engineering and 

environmental costs, administration, repair and maintenance, periodic well work-over costs, 

electric power consumption, miscellaneous supplies) 1,240 wells @ $5,000/well/year for 25 years 

TAXES AND ROYALTIES $402,500,000 

(See Table 4.14-5, Projected Tax Revenues and Royalties: includes ad volorem property tax, 

severance tax, federal and state mineral royalties, and sales and use taxes) 

EARNINGS $202,300,000 

(Pre-corporate federal income tax, before depreciation expense and allowable depletion rates) 

The various tax revenues for the proposed 30-year life of the Seminoe Road Project are set forth 

in Table 4.14-5, Projected Tax Revenues and Royalties. Details of these revenues are set forth 

in the following discussion. 

Ad Volorem Property Taxes. These are taxes on a commodity as a percentage of its value. 

Ad volorem taxes on natural gas production in Wyoming go directly to the county in which the gas 

is produced. Wyoming ad volorem taxes are divided into two types: 

(1) Production and 

(2) Property. 

Production taxes, as the name implies are levied on the assessed valuation of the commodity 

amount produced. Property taxes are levied on wells and producing equipment. The property 

taxes are levied in mils (thousandths of a percent) set by each Wyoming county. The Carbon 

County ad volorem tax rate was estimated at 75 mils. This value was used to calculate project life 

ad volorem property tax estimates. See Table 4.14-5, Projected Tax Revenues and Royalties. 

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November 2005 Draft Environmental Impact Statement

1 Table 4.14-5, Projected Tax Revenues & Royalties

AD VOLOREM PROPERTY TAXES $120,500,000 

Production Ad Volorem - $1,500,000,000 @ 75 mil rate @ 100% of value = $112,500,000 

Property Ad Volorem 

� Assume 10% of capital and development assessment from Table 4.14-4, Estimated 

Revenues and Costs subject to property ad volorem $62,000,000 @ 10% $62,000,000 

� Assume average 50% depreciation in Property over 30 year life $62,000,000 @ 50% = 

$31,000,000 

� Assume industrial property taxes at 11.5% of value $31,000,000 @ 11.5% = $3,565,000 

� Assume 75 mil rate for 30 year life $3,565,000 @ 75 mil rate for 30 years = $8,021,000 

(assume $8,000,000) 

SEVERANCE TAXES $90,000,000 

($1,500,000,000 total revenues @ 6% rate) 

FEDERAL MINERAL ROYALTIES $185,625,000 

(Assume 99% of gas production from federal leases: 0.99 x $1,500,000,000 @ 12.5% rate) 

STATE MINERAL ROYALTIES $2,500,000 

(Assume 1% of gas production from state leases: 0.01 x $1,500,00,000 @ 16.67% rate) 

SALES AND USE TAXES $3,875,000 

(Assume 50% of development, operational and reclamation expenditures shown on Table 4.14-4, 

Estimated Revenues & Costs, subject to sales and use taxes) 

� Wyoming sales tax – 0.50 x $155,000,000 @ 4% rate = $3,100,000 

� Carbon County local use tax – 0.50 x $155,000,000 @ 1% rate = $775,000 

CORPORATE FEDERAL INCOME TAXES $35,400,000 

(Assume 50% of earnings from Table 4.14-4, Estimated Revenues and Costs, taxable at 35% tax 

rate) $202,300,000 x 0.50 x 0.35 = $36,785,000 

EMPLOYEE RELATED TAXES $40,730,000 

(Assume $132,660,000 in total (direct and indirect) payroll income – see Table 4.14-2, Estimated 

Payroll Income 

� State/local taxes as % of income (8.5%) = $11,280,000 

� Federal taxes as % of income (22.2%) = $29,450,000 

Note: 

1. Tax revenues and royalties are estimated for life of the project in 2003 dollars. 

In reality, the ad volorem property tax mil levies are adjusted each year by Carbon County 

commissioners and officials of the various taxing districts, and most mil levies change year to year 

in order to reflect the revenue needs of the taxing entity and the estimates of assessed valuation 

within each taxing district. Natural gas is assessed based on the previous year’s production, and 

well field facilities are depreciated after the first year of production. 

Ad Volorem property taxes are primarily used to fund school districts. 

Wyoming Severance Taxes. The Wyoming Department of Revenue collects and distributes a 

state tax based on mineral production. The current severance tax rate for natural gas is 6% on the 

fair market value of natural gas produced within the state. The severances taxes expected to be 

collected from the Seminoe Road Project over the life of the project are estimated in Table 4.14­

5, Projected Tax Revenues and Royalties. Severance tax revenues fund a variety of state level 

projects and go into a number of accounts, including the General Fund, the Water Development 

Fund, the Mineral Trust Fund and the Budget Reserve, as well as a portion being distributed back 

Seminoe Road Gas Development Project 4­111
Draft Environmental Impact Statement November 2005

to Wyoming counties and municipalities. Wyoming distributed $279 million in severance taxes in 

the year 2000. 

Federal Mineral Royalties. The U.S. government collects a 12.5% royalty on the fair market 

value of gas produced from federal leases, less production and transportation costs. Half of the 

mineral royalty revenues are returned to the state where the minerals were produced. In 

Wyoming, a portion of the state’s share is distributed to local governments and to the Wyoming 

School Foundation Fund. Federal mineral royalties expected to be collected over the life of the 

Seminoe Road Project are set forth in Table 4.14-5, Projected Tax Revenues and Royalties. 

Wyoming Mineral Royalties. The State of Wyoming receives a royalty of 16.67% on the fair 

market value of gas produced from state leases. Similar to severance taxes, these state royalties 

are used for state expenses, and a portion of these royalties are returned to local counties and 

municipalities. 

Sales and Use Taxes. Wyoming collects a 4% sales and use tax on the gross receipt of sales 

and tangible goods and certain services (drilling services are exempt). The state returns 28% of 

the revenue (less administrative costs) to the county where the taxes were collected. Counties 

distribute the revenues to incorporated municipalities based on population. 

Carbon County also levies a 1% local optional sales and use tax that is distributed to the County 

and its municipalities. 

The amount of sales and use taxes to be paid on goods and services for the life of the Seminoe 

Road Project is estimated in Table 4.14-5, Projected Tax Revenues and Royalties. 

Employee Related Taxes. Wyoming does not have corporate or personal income taxes. State 

and local taxes are (property taxes, general sales taxes, motor vehicle licensing, and other 

miscellaneous taxes) estimated to be 8.5% of Wyoming workers’ income. Employee related state 

and local taxes collected over the life of the Seminoe Road Project are set forth in Table 4.14-5, 

Projected Tax Revenues and Royalties. 

In addition, the Seminoe Road Project workforce and the indirect employment workforce would 

pay federal income tax and other federal taxes based on income. It is estimated that these federal 

taxes represent 22.2% of a worker’s income. The amount of employee related federal taxes paid 

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November 2005 Draft Environmental Impact Statement

over the life of the Seminoe Road Project are set forth in Table 4.14-5, Projected Tax Revenues 

and Royalties. 

4.14.2.7 Social Values

Carbon County has a long history of oil and gas development, and consequently most residents 

are generally familiar with the natural gas industry activities and their economic benefits. The 

combination of familiarity and anticipated economic benefit creates a climate of general 

community acceptance of and support for continued and expanded oil and gas development 

within the County. Combined with this general climate of acceptance are resident attitudes and 

values that may diminish support or create opposition for a particular development proposal, 

especially if residents perceive that such development might damage wildlife habitat or degrade 

the quality of recreation. 

These attitudes and values are evident in the comments submitted in response to the BLM 

scoping process for the Seminoe Road Project. Additionally, a discussion of these attitudes and 

values, as expressed by Carbon County residents, is included in the findings of the 1996 Resident 

Survey conducted for the Carbon County Land Use Plan. 

According to the Carbon County Land Use Plan, resident response to the survey suggests “a 

need to balance the conservation of natural resources and the economic viability of resourcebased industries in the County.” This sentiment coupled with partial support for leasing more 

federal lands for oil and gas development (about 50% countywide) suggests that development of 

natural gas resources on existing leases would be generally supported by Carbon County 

residents. 

Livestock operators who control property or hold grazing permits within the EIS analysis area may 

experience dissatisfaction with the proposed project if conflicts between grazing and drilling/field 

development activities arise. Opportunities for conflict would probably be reduced once drilling and 

field development activities are completed. 

Objections to the Seminoe Road Project would typically be related to concern over unknown 

changes, loss of personal or local control, concern for long-term well being of the environment, 

and protection of lifestyle. Those who opposed coalbed natural gas development express concern 

that water quality and quantity could be negatively impacted within and immediately surrounding 

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Draft Environmental Impact Statement November 2005

the project. This is coupled with concerns about aesthetic qualities of the environment (such as air 

pollution, noise, traffic, and impact to wildlife). 

Those who support the Seminoe Road Project relate to employment potentials, economic benefit 

to the region, and stimulation of change and growth in the area such as housing, social services 

and infrastructure. Also identified are interests in providing jobs for area youth and unemployed 

workers, and maintaining an ongoing tradition of oil and gas activity in the county. 

4.14.3 Effects of Alternative B (Proposed Action)

The socioeconomic effects of Alternative B would be the same as those addressed under Section 

4.14.2, Effects Common to All Action Alternatives. 

4.14.4 Effects of Alternative C (Pipeline to Reservoir)

The socioeconomic effects of Alternative C would essentially be the same as discussed in Section 

4.14.2, Effects Common to All Action Alternatives. 

4.14.5 Effects of Alternative D (Underground Injection)

The socioeconomic effects of Alternative D would be similar to those addressed in Section 4.14.2, 

Effects Common to All Action Alternatives; however, given the underground injection program, an 

additional 10 to 15 workers will be needed during operations. Like Alternatives B and C, 80% of 

these additional workers would be hired locally in Carbon County so there would be negligible 

increase to the local population as a result of Alternative D. 

The community and public services would not be impacted with these additional workers; 

however, these workers would add to the tax base of Carbon County and at the same time slightly 

diminish overall Proponent earnings. 

4.14.6 Cumulative Impacts

Natural gas exploration and development activities are expected to increase in Carbon County, 

while oil activities remain steady and coal mining continues to decline. 

The Atlantic Rim Project, located southwest of Rawlins, is a major natural gas project in Carbon 

County, and this proposal encompasses over 300,000 acres with expectations of drilling over 

2,000 new wells. The BLM is currently assembling an EIS for the project, and the draft EIS is 

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November 2005 Draft Environmental Impact Statement

expected to be released for public review in mid 2005. It is assumed that the Atlantic Rim Project 

would operate in the same general time frame as the Seminoe Road Project. 

Carbon County, specifically the town of Rawlins, would have sufficient motels, empty trailer 

spaces, and housing to accommodate both the Seminoe Road and Atlantic Rim projects, along 

with other miscellaneous natural gas development in the area. In addition, Rawlins has sufficient 

community and public service infrastructure for these projects. The local economy and tax base 

would benefit from the potential revenues and taxes generated from these two natural gas 

projects. 

4.14.7 Potential Monitoring and Mitigation

Consistent with any surface owner agreement, the Proponent would coordinate project activities 

with ranch management operations to minimize conflicts with livestock movement or other ranch 

operations. 

4.15 Accidents and Spills

Accident and Spill Impact Significance Criteria: Accidents and spills would be considered 

significant if they caused environmental damage (such as a fuel spill into an area drainage) or 

caused injury to public and employee health and safety. 

There are an infinite number of accident and spill scenarios that could be developed for a project 

like the Seminoe Road Project. Analysis of such scenarios can include varying levels of 

complexity and portray a variety of results. 

Strict safety procedures and precautions are mandated by safety regulations of OSHA. Over the 

years, systems have been developed to ensure safe working environment for the people who 

work the well sites, as well as those individuals working with natural gas pipelines. Strict safety 

procedures and precautions are mandated by safety regulations of OSHA. 

As discussed in Section 4.12, Transportation, diesel fuel would be hauled to the EIS analysis 

area, with the most substantial volumes needed during construction and drilling activities. There is 

always the risk of an accidental spill during the transportation of diesel fuel. The impact from a 

transport related diesel spill would depend on a number of conditions including: 

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Draft Environmental Impact Statement November 2005

� Accident severity and volume of spill; 

� Integrity of the transport containers; 

� Clean-up response time and effectiveness; 

� Weather conditions; 

� Local soil and vegetation types; 

� Proximity of the accident to a stream; and, 

� Volume of receiving water body. 

A WAPA 69 kV electric transmission line and a Conoco high-pressure fuel pipeline cross the EIS 

analysis area. Similar to what was stated above, scenarios for accidents associated with these 

two facilities are unlimited. 

Prior to project start-up, the Proponent would prepare a detailed Hazardous Material Management 

Plan, which would include emergency response procedures. The Proponent would coordinate with 

the BLM in the preparation of this plan, as the BLM has its own Rawlins Field Office procedures 

for emergency response measures. The Proponent’s plan would be kept on-site, and employees 

would receive training pertaining to hazardous materials and emergency response. The 

Hazardous Material Management Plan is described in Appendix G, Hazardous Materials 

Management Plan. 

4.16 Irreversible and Irretrievable Commitment of Resources

Irreversible resource commitments are those that cannot be reversed (loss of future options), 

except perhaps in the extreme long-term. It relates primarily to non-renewable resources, such as 

oil and gas, minerals, cultural resources or those resources that are renewable only over long 

periods of time, such as mature vegetation or forests. Projects such as the Seminoe Road Project 

are designed to remove natural gas from the ground; this action results in an irreversible loss of 

the natural gas resource. 

Irretrievable resource commitments are those that are lost for a period of time. Examples are: the 

loss of production, harvest, or use of natural resources such as wildlife habitat or grazing use, until 

disturbed sites are reclaimed and revegetation success is achieved. For example, if a grazing 

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November 2005 Draft Environmental Impact Statement

allotment is in poor condition and is likely to remain so, the time gap between its current condition 

and its ideal (potential) productivity is an ongoing irretrievable loss. 

Given the planned well pad spacing within the EIS analysis area, overall disturbance would be 

minimal, less than 5% of the area would be affected by well pads and access roads. However, 

during this activity, some existing grazing and wildlife habitat would be disturbed during the 

estimated life of the project and for a period thereafter. With reclamation of these disturbed sites, 

land uses would essentially return to current uses and levels of use or even be enhanced, but this 

could take a period of time for some resources. 

4.16.1 Irreversible Resource Commitment

The irreversible commitment of resources would include the consumption of non-renewable 

energy or materials, such as diesel fuel and gasoline, and effects to natural gas resources and 

cultural resources. 

To extract the natural gas resources from coal seams, ground water resources would be pumped 

during the project life. Given the low recharge rates within and surrounding the EIS analysis area, 

the pumping of water would result in an irreversible commitment. Eventually, the hydrology of the 

area would return to a similar condition that existed prior to natural gas extraction, but this could 

take decades. On the other hand, pumping of water from the EIS analysis area during the 30 year 

life of the project could be used to offset downstream depletions in the North Platte River, 

particularly for threatened and endangered waterfowl species in Nebraska. 

Fossil fuels (diesel and gasoline) used during the construction, operation and transportation 

aspects of the project would result in irreversible commitments of those resources. The extraction 

of natural gas from the EIS analysis area would also result in an irreversible use of the natural gas 

resource. On the other hand, however, the extraction and use of natural gas would make this 

resource available for society. 

Any soil or subsoil material not salvaged prior to disturbance could result in an irreversible 

commitment. In addition, any disturbance of cultural sites could result in an irreversible 

commitment. 

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4.16.2 Irretrievable Resource Commitment

Vegetation removed from well pad sites, roads, and utility line corridors would result in an 

irretrievable resource commitment. Similarly, such activity could displace wildlife (e.g., loss of 

habitat). Reclamation plans and mitigation measures would eventually return vegetation and 

restore wildlife habitat. 

4.17 Unavoidable Adverse Effects

There are unavoidable impacts, which could occur as a result of natural gas extraction from the 

EIS analysis area. Some of these effects would be short-term, while others would be long-term. 

These unavoidable effects could include: 

� The generation of fugitive dust and gaseous emissions (short-term); 

� The loss of vegetation and wildlife habitat (short- and long-term); 

� The extraction of ground water resources (long-term); 

� The use of water resources for dust control (short-term); 

� The demand on public services and utilities (short-term); 

� Loss of wetlands, riparian areas, springs and seeps (short- and long-term); 

� The visual effects for travelers on County Road 351 (short-and long-term); 

� Increases in noise levels which could effect human aesthetics and wildlife use and 

effectiveness (short-term); and, 

� Increased road traffic (short-term). 

4.18 Short­Term Use Versus Long­Term Productivity

Short-term uses are those that generally occur on a year-to-year basis. Examples are wildlife and 

livestock use of forage, recreation and use of the water resource. Long-term productivity is the 

capability of the land to provide resources, both market and non-market, for future generations. 

Relationships between short-term uses of the environment and long-term productivity occur in all 

alternatives. Short-term uses such as natural gas extraction may be said to represent irretrievable 

commitments of resources. As an example, removal of vegetation from well pads and roads 

certainly prevents the vegetation from serving as forage for wildlife and livestock for a certain 

4­118  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

period of time. However, following project closure and final reclamation, revegetation would again 

re-establish and serve the desired purpose. This would occur because the basic long-term 

vegetative productivity would not be destroyed by the short-term use of natural gas extraction; 

therefore, no irreversible damage would occur. 

Natural gas production would be relatively short-term, expecting to last up to 30 years. The shortterm use of the EIS analysis area would be to recover as much natural gas as is economically 

feasible, while mitigating adverse impacts to acceptable levels. 

Long-term productivity refers to the basic capability of the land to produce according to desired 

future levels (e.g., vegetation, wildlife habitat, etc.). Long-term productivity would depend on the 

reclamation measures applied, the ability to retain soil productivity, and the desired long-term 

management objectives. 

All of the alternatives discussed in this EIS result in short-term uses which irretrievably commit 

certain resources. Proper reclamation and environmental mitigation should restore any disturbed 

sites to long-term productivity. 

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Chapter 5 – List of Agencies, Organizations and 

Individuals to Whom Copies of the 

Draft EIS Were Sent 

Copies of the draft EIS are available for review at the BLM offices in both Rawlins and Cheyenne, 

Wyoming, as well as the Carbon County Library in Rawlins. 

Copies of the draft EIS were distributed to the following governmental agencies, organizations and 

individuals. 

5.1 Federal Agencies 

Army Corps of Engineers 

Bureau of Indian Affairs 

Bureau of Land Management Library 

Bureau of Land Management, MS1075 

Bureau of Land Management, Rawlins Field Office 

Bureau of Land Management, Wyoming State Office 

Bureau of Reclamation, Casper Office 

Bureau of Reclamation, Office of Program and Policy Services 

Department of Energy, Western Area Power Administration 

Department of the Interior, National Science and Technology Center 

Department of the Interior, Natural Resources Library 

Department of the Interior, Office of Environmental Policy and Compliance 

Department of the Interior, Office of Environmental Policy and Compliance 

Department of the Interior, Regional Environmental Officer 

Environmental Protection Agency, Office of Federal Activities 

Environmental Protection Agency, Region VIII 

Federal Energy Regulatory Commission 

Fish and Wildlife Service, Denver Office 

Fish and Wildlife Service, Division of Federal Projects 

Fish and Wildlife Service, Ecological Services 

Forest Service, Bridger-Teton National Forest 

Forest Service, Medicine Bow-Routt National Forest 

Seminoe Road Gas Development Project 5-1 
Draft Environmental Impact Statement November 2005 

Forest Service, Pinedale Ranger District 

State Government 

Geological Survey 

Government Printing Office 

Library of Congress 

Minerals Management Service 

National Park Service 

National Park Service, Air Resources Division 

National Park Service, NEPA/Section 106 Specialist 

Natural Resource Conservation Service, Wyoming State Office 

Office of Surface Mining 

5.2 Tribal Governments 

Cheyenne River Sioux Tribal Council 

Cheyenne River Sioux Tribe, Tribal historic Preservation Officer 

Comanche Tribal Business Council 

Crow Tribal Administration, Cultural Director 

Crow Tribal Council 

Medicine Wheel Coalition for Sacred Sites of North America 

Northern Arapaho Business Council 

Northern Arapaho Tribe, Tribal historic Preservation Officer 

Northern Cheyenne Tribal Council 

Northern Cheyenne Tribe, Traditional Spokesman 

Northern Cheyenne Tribe, Tribal Historic Preservation Officer 

Ogala Sioux Tribal Council 

Rosebud Sioux Tribal Council 

Rosebud Sioux Tribe, Cultural Resource Coordinator 

Shoshone and Northern Arapaho Tribes, Wind River Environmental Quality Commission 

Shoshone Business Council 

Shoshone Business Council 

Shoshone Cultural Office 

Shoshone-Bannock Tribes of Fort Hall, Business Council 

Shoshone-Bannock Tribes, Interim Cultural Resource Coordinator 

5-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Southern Ute Indian Tribe 

Ute Indian Tribe, Cultural Rights and Protection 

Ute Tribal Council 

5.3 Elected Officials 

U.S. Representative Barbara Cubin 

U.S. Representative Barbara Cubin, Cheyenne Field Office 

U.S. Representative Barbara Cubin, Rock Springs Field Office 

U.S. Representative Craig Thomas, Cheyenne Field Office 

U.S. Senator Craig Thomas 

U.S. Senator Craig Thomas, Rock Springs Field Office 

U.S. Senator Mike Enzi 

U.S. Senator Mike Enzi, Casper Field Office 

U.S. Senator Mike Enzi, Cheyenne Field Office 

U.S. Senator Mike Enzi, Gillette Field Office 

Wyoming Senator Bill Vasey 

5.4 State Government 

Colorado State University Libraries 

Field Museum of Natural History, Department of Geology 

Governor’s Planning Office 

Medicine Bow Conservation District 

Nebraska Department of Natural Resources 

Office of the Governor, Environmental Policy Division 

Saratoga-Encampment-Rawlins Conservation District 

University of Wyoming Libraries, Collection and Development Office 

Western Wyoming College, Archeological Services 

Wyoming Association of Municipalities 

Wyoming Business Council 

Wyoming Department of Agriculture 

Wyoming Department of Employment, Research and Planning Division 

Wyoming Department of Environmental Quality, Air Quality Division 

Wyoming Department of Environmental Quality, Land Quality Division 

Seminoe Road Gas Development Project 5-3 
Draft Environmental Impact Statement November 2005 

Wyoming Department of Environmental Quality, Water Quality Division 

Wyoming Department of Environmental Quality, Water Quality Division, Lander 

Wyoming Department of Revenue, Ad Volorem Tax 

Wyoming Game and Fish Department, Green River 

Wyoming Game and Fish Department, Office of the Director 

Wyoming Game and Fish Department, Savery 

Wyoming Natural Diversity Database 

Wyoming Oil and Gas Conservation Commission 

Wyoming Public Service Commission 

Wyoming State Engineer’s Office 

Wyoming State Geological Survey 

Wyoming State Historic Preservation Office 

Wyoming State Parks and Cultural Resources, Historic Sites Division 

5.5 County and Local Government 

Carbon County Commissioners 

Carbon County Planning Commission 

Carbon County Public Library 

Carbon County Road and Bridge Department 

City of Rawlins 

Rawlins and Carbon County Chamber of Commerce 

Rock Springs Library 

Sweetwater County Library System 

Town of Bairoil 

Town of Hanna 

Town of Medicine Bow 

Town of Saratoga 

Town of Sinclair 

5.6 Businesses and Organizations 

3-Shot Sage Grouse Foundation 

Air Quality Resource Management 

Anadarko Petroleum Corporation 

5-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Anadarko Petroleum Corporation, Rock Springs 

Animal Welfare Institute 

Audubon Society, Cheyenne 

Bio Environmental Associates 

Biodiversity Conservation Alliance 

Bjork, Linkley, and Little, PC 

Carbon County Coalition 

Casper Star-Tribune 

Casper Star-Tribute, Green River 

CBMCC 

Coleman Oil and Gas 

Colorado Interstate Gas Company 

Colorado River Basin Salinity Control Forum 

Continental Divide Trail Society 

Defenders of Wildlife 

Desert Cattle Company 

Devon SFS Operating Inc. 

DRU Consulting, LLC 

Dudley and Associates, LLC 

Earth Tech 

Earthjustice Legal Defense Fund, Inc. 

Energy Analysts 

Environmental Defense 

Evergreen Construction 

Fisher Ranch 

Flying J Oil and Gas Inc. 

Forsberg Ranch 

Gary Holsan Environmental Planning 

Gerald Jacob Environmental Consulting 

Greystone 

Hayden Wind Associates 

Hi-Allen Ranch Company 

HIS Energy Group 

Seminoe Road Gas Development Project 5-5 
Draft Environmental Impact Statement November 2005 

Hyland Enterprises 

ID Ranch 

IPAMS 

Julander Energy Company 

Kaiser-Francis Oil Company 

KCWY-TV 

Klabzuba Oil and Gas 

KRAL/KIQZ 

KTWO-TV and KTWO Radio 

KUWR 

Land and Water Fund of the Rockies, Wyoming Representative 

Lander Journal 

Laramie Daily Boomerang 

MacPherson, Kelly and Thompson, LLC 

McElvain Oil and Gas Properties 

Miller Estate Company 

National Wildlife Federation 

National Wildlife Federation, Boulder Office 

Natural Resources Defense Council 

OCI Wyoming LP 

OCTA 

OCTA – Wyoming Chapter 

Oil and Gas Accountability Project 

PacifiCorp 

People for the West 

Petrogulf Corporation 

Petroleum Association of Wyoming 

Poulson, Odell and Peterson 

Power River Basin Resource Council 

Predator Project 

Public Lands Advocacy 

Q Creek Grazing Association, LLC 

Qwest 

5-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Rawlins Daily Times 

River Gas Corporation 

Rocky Mountain Casing Crews Inc. 

Rocky Mountain Sheep Grazing Association 

Saratoga Sun 

Schmid Oilfield Services, Inc. 

Seminoe Boat Club 

Sierra Club 

Sierra Club, Montana 

Sinclair Oil Company, Casper Refinery 

Sinclair Oil Corporation 

Southwest Wyoming Industrial Association 

Swift Creek Consulting 

The Natural Resources Defense Council 

The Nature Conservancy 

The Nature Conservancy, Public Land Program 

The Sierra Club, Wyoming Chapter 

The Wilderness Society 

Three Forks Ranch Corporation 

Thunder Basin Consulting 

TRC Environmental Corporation 

TRC Mariah 

Trigon-Sheehan, LLC 

Trout Unlimited 

Uintah Engineering and Lands Surveying 

URS, Woodward-Clyde 

US Energy/Crested 

Wamsutter Ltd. Partnership 

WESTECH 

Western Ecosystems 

Western Gas Resources 

Western Wyoming Mule Deer Foundation 

Wildlife Management Institute 

Seminoe Road Gas Development Project 5-7 
Draft Environmental Impact Statement November 2005 

Wildlife Management Institute 

Williams Field Services 

Wyoming Association of Professional Archaeologists 

Wyoming Association of Professional Archeologists, Governmental Affairs Committee 

Wyoming Outdoor Council, Attorney at Law 

Wyoming Outdoor Council, Field Director 

Wyoming Outdoor Council, Rawlins 

Wyoming People for the USA 

Wyoming Sportsman’s Association 

Wyoming Wilderness Association, Greater Yellowstone Coalition 

Wyoming Wildlife Federation 

Wyoming Wildlife Federation, Lander 

Wyoming Woolgrowers Association 

Yates Petroleum Corporation 

5.7 Individuals 

Archard, James A. and Betty C.


Arthur, Tom


Barber, Craig


Bate, Richard H.


Bayless, Robert L.


Binger, Terry L. and Janet L.


Bowen, Roland E. and Cheryl J.


Brashier, G.W.


Bryan, James M. and Joanne H.


Cameron, Isaac


Cameron, Vanessa


Capehart, Lewis F. and Connie M.


Clark, Rita


Comeau, Nancy H.


Cope, Leroy J. and Margaret M.


Corrado, Robert J. and Patricia L.


Cox, Gerald D. and Judith N.


5-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Dally, Maro 

Dixon, Donald and Mary 

Duchame, Richard 

Dyer, Brenda Dawn and James E. 

Fitzgerald, Byron 

Fleming, Linda 

France, Dwight 

France, John W. 

French, Kathryn Capeline 

Frost, Chris 

Graebert, Thomas A. and Jeanne 

Hall, Roy L. and Marie E. 

Hammarsten, LaVern 

Hardy, Max D. and Naomi 

Head, Jennifer 

Heisner, William C. Jr. 

Hepworth, William 

Herman, Darlene G., Carrie, and Roberta 

Hittel, Earline 

Hochenauer, John A. 

Holt, Gabriel 

Hornbeck, Kirby C. 

Hunt, Mary E. 

Hurst, Neil 

Ihasz, Oliver D. 

Jaramillo, Catherine J. and John V. 

Jerome, Mary Ann 

Johnson, M.C. 

Jones, Bill 

Jons, Leroy and Margaret 

Kamon, Ken 

Kem, Carl 

Kempa, Stanley W. 

Seminoe Road Gas Development Project 5-9 
Draft Environmental Impact Statement November 2005 

Kinnamen, Angeline M. 

Kromrey, Jerry E. 

Larsen, Sain 

Manierre Ernest R. 

Martzke, James F. and Vicki J. 

Maxson, Joe 

McCarthy, Tom 

McKean, Lee G. and Barbara J. 

McKenna, Malcolm 

McNulty, Terrence M. 

Miller, Damien 

Morgan, Trent 

Morrison, Jimmy D. 

Morrison, Orview E. and Carolyn 

Morrow, Land and Jill 

Morrow, Moe 

Mullen, Tim 

O’Connel, R.K. 

Patterson, Sandra Earlene 

Perez, Henry G. and Teresa 

Pilgrim, Roger J. and Margaret 

Porter, Pat R. and Faye 

Ravia, Noah C. and Julia 

Reiker, Joseph C. 

Rochelle, Curtis 

Roush, Rodger A. and Mary E. 

Sarver, Thomas R. Jr. 

Scherer, Robert L. 

Shaffer, William K. 

Shipman, Randy 

Sikocinski, Lorraine T. 

Simon, Charles W. and Evelyn M. 

Slattery, Frederick M., Jr. 

5-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Southerlands, The


Strang, John P.


Todd, Harry L., Jr.


Todd, Raymond L.


Vievins, Michael J.


Vold, Joseph S. and Charlotte L.


Waldron, Mary F. and Lewis C.


Wiggins, Audrey C.


Zieger, Art


Zielinski, Richard Charles


Seminoe Road Gas Development Project 5-11 
November 2005 Draft Environmental Impact Statement 

Chapter 6 – List of Preparers

6.1 Introduction 

The BLM is the lead agency for the Seminoe Road Project EIS and is responsible for the contents 

of this EIS document. S. Edwards Inc. served as the third-party EIS contractor under the direction 

of the lead agency and utilized numerous subcontractors in the assemblage of the EIS. A number 

of individuals have contributed to this document. The academic background and experience of the 

third-party contractor (S. Edwards Inc) and its subcontractors are presented in this chapter. 

6.2 Bureau of Land Management 

David Simons – Environmental Coordinator 

Bob Lange – Hydrology 

Heath Cline – Wildlife 

Mike Bower – Fisheries 

Patrick Walker – Archaeology 

Krystal Clair – Recreation and Visual Resources 

Susan Foley – Soils and Vegetation 

Larry Jackson – Natural Resource Specialist 

Mike Murray – Range 

Mark Newman – Geology 

Hugh Wolfe – Realty Specialist 

Susan Caplan – Air Quality 

6.3 Saratoga – Encampment – Rawlins Conservation District 

Jeb Stewart 

Larry Bentley 

6.4 S. Edwards Inc. 

Alan Czarnowsky – Project Manager: B.S. in Mining Engineering, 1975, Colorado School of 

Mines. Experience in mining and oil/gas operations and environmental aspects of projects and 

operations in western North America, including Alaska. 

Seminoe Road Gas Development Project 6-1 
Draft Environmental Impact Statement November 2005 

Dan Keuscher – Assistant Project Manager/Engineer/Transportation: B.S. in Mining Engineering, 

1974, University of Nevada, Mackay School of Mines. A.A.S. in Hazardous Materials 

Management, Mount Hood Community College. Additional college coarse work in ecology, 

reclamation and wildlife habitat. Experience in planning, operations, environmental management, 

and reclamation of western United States and South American mining operations. 

Rita Edinger – Document Coordination/Word Processing – United States Army Training Center, 

Fort Jackson, South Carolina, 1974. Clerical, management, and administrative experience, in 

particular on EA and EIS documents for western United States mining and oil/gas activities. 

6.5 S. Edwards Inc. Primary Consultants 

Joe Frank – Groundwater: M.S. in Hydrogeology/Geology, 1987, and B.S. in Geology 1978, 

University of Colorado. President and Senior Hydrogeologist/Geologist with HydroGeo 

Consultants, Inc. Twenty-five years experience in hydrogeologic studies for mining and oil/gas 

projects in the United States and abroad. Experience includes surface and ground water technical 

studies, ground and surface water computer modeling, well installation and logging, aquifer testing 

and analysis, and water quality sampling. 

Scott Effner – Groundwater: B.S. in Geology, 1988 and M.S. in Geological Science, 1992, 

University of Idaho. Senior Hydrogeologist and Geochemist with HydroGeo Consultants, Inc. and 

Whetstone Associates Over twelve years experience working on projects in the United States and 

abroad. Experience in geochemical and ground water technical studies, ground water flow and 

contaminant transport modeling, well installation and testing, packer permeability testing, and 

water quality sampling. 

Gabriele Walser Ph.D.: – Surface Water Model: Ph.D. in Civil Engineering from the University of 

Colorado; an M.S. degree in Environmental Engineering from the University of Montana; and a 

Dipl. Ing. (FH) degree in Engineering Physics and Environmental Engineering from 

Fachhochschule München, Germany. Senior Engineer and Hydrologist for HydroGeo, Inc. with 

over 12 years of experience in surface and ground water hydrologic studies and surface and 

ground water computer modeling. 

Steve Long – Soils/Vegetation/Wetlands: M.S. in Regional Resource Planning/Soil Science 

Reclamation, 1977, Colorado State University. B.S. in Wildlife Biology, 1972, Colorado State 

6-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

University. Principal of Cedar Creek Associates, serving as the soils and wetlands specialist. 

Twenty-seven years of experience in environmental management and remediation design. 

Cathy Frank – Vegetation/Wetlands: B.A. Biological Sciences, 1977, University of Colorado – 

Boulder. Colorado Department of Education Type A Secondary Science Teaching Certification, 

Biological Sciences, University of Colorado - Boulder 1979. Senior botanist and plant ecologist for 

HydroGeo, Inc. Twenty-seven years of experience in botanical fieldwork and environmental 

studies. 

Mike Phelan – Wildlife/Fisheries: B.A. in Zoology, 1972, University of California, with postgraduate studies in biology and ecology from San Diego State University. Principal of Cedar 

Creek Associates, serving as the wildlife specialist. Nearly thirty years of experience in wildlife 

studies in western North America. 

Jim Brechtel – Archaeology: M.A. in Anthropology/Archaeology, 1980, University of Northern 

Colorado and B.A. in Anthropology, 1976, Colorado State University. Nearly twenty-five years as 

consulting archaeologist working on hundreds of archaeological compliance projects in the 

western United States. 

Gary McFaddin – Air Quality: B.S. in Chemical Petroleum Refining, 1981 and M.S. Chemical 

Petroleum Refining, 1985, Colorado School of Mines. President and Principal Engineer of 

Compliance Partners, Inc. Nearly twenty years of air quality experience working on mining and 

oil/gas projects in western North America. 

Joe Nagengast – Drafting and Graphics: Billings Vo-Tech College, AA Drafting Technology, 

1978. Design technology studies at Northern Montana College and geologic studies at Eastern 

Washington University. Studies in AutoCAD I, II, III and AutoCAD Management at CAD Institute in 

Phoenix, Arizona. President and Principal Graphics Specialist at Nagengast Brothers, LLC. Over 

twenty-five years experience in geologic, mining, civil, oil and gas, and environmental graphics 

and design. 

Seminoe Road Gas Development Project 6-3 
November 2005 Draft Environmental Impact Statement 

Chapter 7 - References 

Andrews, R. and R. Righter. 1992. Colorado birds. Denver Museum of Natural History, Denver, 

Colorado. 442 pp. 

Arch Coal. 2004. http://www.archcoal.com/aboutus/archofwyoming.asp. 

Baxter, G.T. and M.D. Stone. 1985. Amphibians and reptiles of Wyoming. (2nd Edition) Wyoming 

Game and Fish Department, Cheyenne, Wyoming. 137 pp. 

Beinap, Jayne, R. Rosentreter, S. Leonard, J.H. Kaltenechkler, J. Williams, and D. Eldridge. 2001. 

Biological soil crusts: ecology and management. USDI Bureau of Land Management 

Technical Reference 1730-2. 

Beinap, Jayne. 1995. Surface disturbances: their role in accelerating decertification. 

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Breithaupt, B.H., 1985. Non-mammalian Vertebrate Faunas from the late Cretaceous of Wyoming. 

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Busnel, R.G. 1978. Introduction, pp 7-22 In: Fletcher, J.L. and R.G. Busnel (eds). 1978. Effects of 

Noise on Wildlife. Academic Press. New York. 

Seminoe Road Gas Development Project 7-1 
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Campbell, T.M., III and T.W. Clark. 1981. Colony characteristics and vertebrate associates of 

white-tailed and black-tailed prairie dogs in Wyoming. American Midland Naturalist, 105:269­

275. 

Carter, Patsy, Memorial Hospital of Carbon County, 2004. Personal Communication. 

Case, J.C., R.N. Toner, and R. Kirkwood, 2002. Basic Seismological Characterization for Carbon 

County, Wyoming. Wyoming State Geological Survey, September 2002. 

Cedar Creek Associates, Inc. 2004. Biological investigations for the Seminoe Road Coalbed 

Methane Pilot Project area and potential expanded pilot project area. Unpublished report to be 

prepared by Cedar Creek Associates, Inc., Fort Collins, Colorado. 

Clark, T.W. and M.R. Stromberg. 1987. Mammals in Wyoming. Public Education Series, 

University of Kansas, Museum of Natural History, 10:1-314. 

Conder, Al. 2004. Biologist, Wyoming Game & Fish Department. Personal communication with 

Mike Phelan, Cedar Creek Associates. 

Cowardin, L.M., V. Cater, F. Golet, and E. LaRoe. 1979. Classification of Wetlands and deepwater 

habitat of the United States. USFWS. FWS/OBS-79/31, 103 pp. 

Cox, Roger. District Conservationist. Natural Resources Conservation Service. Saratoga, 

Wyoming. Personal communication. January 2004. 

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Paleontology of the Fox Hills and Lower Medicine Bow Formations of Southern Wyoming and 

Northwestern Colorado; 2, Flora of the Lance Formation at its Type Locality, Niobrara County, 

Wyoming. Carnegie Institution of Washington Publication 508. 

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138 pp. 

Dudley & Associates, LLC, 2005. Pilot Project pressure observation well data. 

7-2 Seminoe Road Gas Development Project 
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Eberle, J.J. and J.A. Lillegraven, 2003. A new important record of the earliest Cenozoic 

mammalian History: Geologic Setting, Multituberculata, Peradictia and Eutheria 

paleogeographic/biostratigraphic summaries. In Rocky Mountain Geology 33.1. 

Ehrlich, P.R., D.S. Dobkin, and D. Wheye. 1988. The birder's handbook, a field guide to the 

natural history of North American birds. Simon & Schuster Inc., New York. 785 pp. 

Eldridge, D.J. and R.S. B. Greene. 1994. Microbiotic soil crusts: a review of their roles in soil and 

ecological processes in the rangelands of Australia. 

EPP, Robert. 2004. BLM, Rawlins Field Office. Information Provided to Daniel Keuscher (SEI). 

Fitzgerald, J.P., C.A. Meaney, and D.M. Armstrong. 1994. Mammals of Colorado. Denver 

Museum of Natural History, University Press of Colorado, Niwot, Colorado. 467 pp. 

Foley, Susan. Soil Scientist. Bureau of Land Management. Rawlins, Wyoming. Personal 

communication with Mr. Steve Long of Cedar Creek Associates. August 2002. 

Foley, Susan. Soil Scientist. Bureau of Land Management. Rawlins, Wyoming. Personal 

communication with Mr. Steve Long of Cedar Creek Associates. August 2003. 

Foley, Susan. Soil Scientist. Bureau of Land Management. Rawlins, Wyoming. Personal 

communication with Mr. Steve Long of Cedar Creek Associates. January 2004. 

France, Carbon County Fire Marshal, 2004. Personal Communication with Mr. Dan Keuscher of S. 

Edwards Inc. 

Freeze, R.A., and J.A. Cherry, 1979. Groundwater. Prentice Hall, Inc., Englewood Cliffs, New 

Jersey, 603 pp. 

Frison, George C. 1991. Prehistoric Hunters of the High Plains. Second Edition. Academic Press, 

New York. 

Seminoe Road Gas Development Project 7-3 
Draft Environmental Impact Statement November 2005 

Gill, J.R., E.A. Merewether, and W.A. Cobban, 1980. Stratigraphy and Nomenclature of Some 

Upper Cretaceous and Lower Tertiary Rocks in South-central Wyoming. U.S. Geological 

Survey Professional Paper 667. 

Glass, G.B. and J.T. Roberts, 1980. Coals and Coal Bearing Rocks of the Hanna Coal Field, 

Wyoming, Geological Survey of Wyoming, Report of Investigations No. 22. 

Goodfellow, W.L., L.W. Ausley, D.T. Burton, D.L. Denton, P.B. Dorn, D.R. Grothe, M.A. Heber, 

T.J. Norberg-King, and J.H. Rodgers, Jr., 2000: Major ion toxicity in effluents: a review with 

permitting recommendations. Environ. Toxicol. Chem. 19: 175-182. 

Hausel, W.D., 1994. Economic Geology of the Seminoe Mountains Mining District. Wyoming State 

Geological Survey, Report of Investigation, No. 50. 

HydroGeo, Inc. and TRC Mariah Associates, Inc. 2001. Spring 2001 Monitoring, Seminoe Road 

Project. Report prepared for Dudley & Associates, LLC. 

HydroGeo, Inc., 2001. Fall 2001 Monitoring, Seminoe Road Project. Report prepared for Dudley & 

Associates, LLC. 

HydroGeo, Inc. 2003a. 2002 Baseline Hydrologic Monitoring Study, Seminoe Road Gas 

Development Project. Prepared for Dudley & Associates, LLC. 

HydroGeo, Inc. 2003b. Modeling Approach and Preliminary Input Parameters for Numerical 

Modeling of Ground Water Flow and Surface Water Quality, Dudley & Associates, LLC, 

Seminoe Road Gas Development Project. Prepared for Bureau of Land Management, 

Rawlins Field Office, June 2003. 

HydroGeo, Inc. 2004a. Draft Groundwater Modeling Technical Report, August 2004. 

HydroGeo, Inc. 2004b. Draft Surface Modeling Technical Report, August 2004. 

HydroGeo, Inc. 2004c. Draft 2003 Vegetation Addendum Report, October 2004. 

7-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

HydroGeo, Inc. 2004d. Seminoe Road Project Water Quality Database, unpublished document. 

Lillegraven, J.A., 1993. Correlation of Paleogene Strata Across Wyoming. A User’s Guide. 

Wyoming State Geological Survey Memoir 5. 

Lillegraven, J.A., 1995. Nature Timing, and Paleogeographic Consequences of Laramide 

Deformation in the Northeastern Hanna Basin, Wyoming. AAPG Rocky Mountain Section 

Meeting; Abstracts AAPG Bulletin 78. 

Lowham, H.W., D.A. Peterson, E.A. Zimmerman, B.H. Ringer, and K.C. Mora, 1985. Hydrology of 

Area 52, Rocky Mountain Coal Province, Wyoming, Colorado, Idaho and Utah. U.S. 

Geological Survey Water Resource Investigations Open File Report 83-761. 

Lyon, A.G. 2000. The potential effects of natural gas development on sage-grouse (Centrocercus 

urophasianus) near Pinedale, Wyoming. Thesis, University of Wyoming, Laramie, USA. 

Robbins, C.S., J.R. Sauer, R.S. Greenberg, and S. Droege. 1989. Population declines in North 

American birds that migrate to the neotropics. Proceedings of the National Academy of 

Science 86:7658-7662. 

Sanders, Carbon County School District 1, 2004. Personal Communication. 

Scheffe, Richard D. 1988. VOC/NOx Point Source Screening Tables. Office of Air Quality Planning 

and Standards, Research Triangle Park, North Carolina. August 1988. 

Simons, Dave. Planning and Environmental Coordinator. Bureau of Land Management. Rawlins, 

Wyoming. Personal communication. November 2003 

Snigg, Mike. 2004. Fisheries Biologist, Wyoming Game & Fish Department. Personal 

communication with Mike Phelan, Cedar Creek Associated. 

Terres, J. K. 1980. The Audubon Society encyclopedia of North American birds. Alfred A. Knopf, 

New York. 1109 pp. 

Seminoe Road Gas Development Project 7-5 
Draft Environmental Impact Statement November 2005 

TRC Mariah Associates, Inc. 2001. Riparian Vegetation Baseline Investigation of Discharge 

Drainage Channels for the Seminoe Road Pilot Project, Carbon County, Wyoming. December 

2001. 

TRC Mariah Associates, Inc. 2000. Biological Assessment for the Seminoe Road Coalbed 

Methane Pilot Project, Carbon County, Wyoming. Prepared by TRC for the BLM, Rawlins 

Field Office, Rawlins, Wyoming. December 2000. 40 pp. + appendices. 

TRC Mariah Associates, Inc. 2002a. Black-footed ferret survey of prairie dog towns 6, 7, 8, 9, 10, 

11, 12, 13, 14, 15, 16, and 18, Seminoe Road Coalbed Methane Pilot Project pipelines, 

Carbon County, Wyoming. Unpublished report prepared by TRC, Laramie, Wyoming. March 

2002. 7 pp. + appendix. 

TRC Mariah Associates, Inc. 2002b. Seminoe Road Coalbed Methane gas gathering pipeline and 

access road project biological investigation. Unpublished letter report prepared by TRC, 

Laramie, Wyoming. April 16, 2002. 9 pp. + table. 

TRC Mariah Associates, Inc. 2002c. Supplement to the Seminoe Road Coalbed Methane gas 

gathering pipeline and access road project biological investigation. Unpublished letter report 

prepared by TRC, Laramie, Wyoming. May 22, 2002. 4 pp. + maps. 

TRC Mariah Associates, Inc. 2002d. 2002 sage grouse lek inventory of the Dudley Leasehold, gas 

gathering pipeline and access road routes, and 2-mile buffer. Unpublished letter report 

prepared by TRC, Laramie, Wyoming. May 22, 2002. 2 pp. + data sheets & map. 

TRC Mariah Associates, Inc. 2002e. Black-footed ferret survey, Seminoe Road Coalbed Methane 

natural gas gathering pipeline and access road project, Carbon County, Wyoming. 

Unpublished report prepared by TRC, Laramie, Wyoming. July 2002. 6 pp. + map & 

appendices. 

TRC Mariah Associates, Inc. 2004. Air Quality Technical Support Document, Atlantic Rim Natural 

Gas Project and the Seminoe Road Gas Development Project. October 2004. 

7-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

USDA Forest Service. 2000. Screening Methods for Calculating ANC Change to High Elevation 

Lakes, User’s Guide. USDA Forest Service, Rocky Mountain Region. January 2000. 

USDI, Bureau of Land Management (BLM), 1990. Great Divide Resource Management Plan. 

USDI, Bureau of Land Management (BLM). 1997. Standards for Healthy Rangelands and 

Guidelines for Livestock Grazing Management for Public Land Administered by the Bureau of 

Land Management in the State of Wyoming August 12, 1997, Bureau of Land Management, 

Wyoming State Office, Cheyenne, Wyoming. 

USDI, Bureau of Land Management (BLM). 2001. Environmental Assessment for the Seminoe 

Road Coalbed Methane Pilot Project, Carbon County, Wyoming, April 2001. 

USDI, Bureau of Land Management (BLM). 2001b. Decision Record and finding of no significant 

impact for the Seminoe Road Coalbed Methane Pilot Project, Carbon County, Wyoming. 

USDI, Bureau of Land Management (BLM). 2002. Environmental Assessment for the Hanna Draw 

Coalbed Methane Exploration Project, Carbon County, Wyoming, June 2002. 

USDI, Bureau of Land Management (BLM). 2002. Water Resources in the Seminoe Reservoir 

Area. Data provided by Bob Lange and Robert Epp of the Rawlins Field Office of the BLM, 

September 2002. 

USDI, Bureau of Land Management (BLM). 2003. Final Environmental Impact Statement and 

Proposed Plan Amendment for the Powder River Basin Oil and Gas Project. January 2003. 

USDI, Bureau of Land Management (BLM). 2004. Phone conversation between Mr. Mike 

Neumann, geologist for the Rawlins Field Office of the BLM and Mr. Joe Frank of HydroGeo, 

Inc., February 10, 2004. 

USDI, Bureau of Land Management (BLM). 2004a. Personal Communication between Mr. David 

Simons, Project Manager for BLM Rawlins Field Office, and Mr. Dan Keuscher of S. Edwards 

Inc. 

Seminoe Road Gas Development Project 7-7 
Draft Environmental Impact Statement November 2005 

USDI, Bureau of Reclamation. 2003. http://www.usbr.gov/gp/aop/np/0102/tables.htm 

USDI, Bureau of Reclamation. 2004. http://www.usbr.gov/dataweb/html/kendrick.html 

USDI, Bureau of Land Management (BLM). 2004b. Personal Communication between Mr. Mike 

Murray, Rangeland Specialist for the BLM Rawlins Field Office, and Mr. Dan Keuscher of S. 

Edwards Inc. 

USDI, Bureau of Reclamation. 2000. Seminoe Reservoir Systems Operation Water Year 2000. 

U.S. Department of Labor, 2003. Occupational Noise Exposure, CFR 29, Part 1926. 

U.S. Fish and Wildlife Service (USFWS). 1984. American peregrine falcon recovery plan (Rocky 

Mountain/ Southwest population). Prepared in cooperation with the American Peregrine 

Falcon Recovery Team. U.S. Fish and Wildlife Service, Denver, Colorado. 105 pp. 

U.S. Fish and Wildlife Service (USFWS). 1984. American peregrine falcon recovery plan (Rocky 

Mountain/ Southwest population). Prepared in cooperation with the American Peregrine 

Falcon Recovery Team. U.S. Fish and Wildlife Service, Denver, Colorado. 105 pp. 

U.S. Fish and Wildlife Service (USFWS). 1989. Black-footed ferret survey guidelines for 

compliance with The Endangered Species Act. U.S. Fish and Wildlife Service, Denver, 

Colorado and Albuquerque, New Mexico. 10 pp. + appendices. 

U.S. Fish and Wildlife Service (USFWS). 2004. http://mountainprairie.fws.gov/special/mammals/blackfootedferret. 

U.S. Fish and Wildlife Service (USFWS). 2002. Birds of Conservation Concern. USFWS, Division 

of Migratory Bird Management. Arlington, Virginia. 99 pp. 

U.S. Geological Survey. 1978. Coal Resource Occurrence Maps of the Seminoe Dam SW 

Quadrangle, Carbon County, Wyoming. Open-File Report 78-060. 

7-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

U.S. Geological Survey. 2002. Streamflow data for the N. Platte River above Seminoe Reservoir 

USGS station 06630000. http://www.waterdata.usgs.gov/nwis 

U.S. Geological Survey. 2004.	 Water quality data for the N. Platte River and Seminoe Reservoir. 

http://www.waterdata.usgs.gov/nwis 

WRCC (Western Regional Climate Center). 2005. Wyoming Climate Summaries. 

http://www.wrcc.dri.edu 

WRDS (Water Resources Data System). 2005. Hydrological and climatological data for the State 

of Wyoming. http://www.wrds.uwyo.edu/. 

Wyoming Department of Environmental Quality. 2001. Water Quality Rules and Regulations, 

Chapter 1, adopted June 21, 2001. 

Wyoming Department of Transportation. 2004. Personal Communication by Mr. Dan Keuscher of 

S. Edwards Inc. 

Wyoming State Engineer. 2002. Surface Water and Ground Water Records for Carbon County 

Wyoming. 

Wyoming Game and Fish Department. 1998. Basin management plan. Provided to Mike Phelan 

(Cedar Creek Associates) by Al Conder (WGFD). 

Wyoming Game and Fish Department. 2003. Wyoming greater sage-grouse conservation plan. 

Wyoming Game and Fish Department, June 24, 2003. 78 pp. + appendices. 

Wyoming Natural Diversity Database (WYNDD). 2002. Botany Comments, Plant Species of 

Special Concern for J. Frank, HydroGeo, Inc. Completed September 12, 2002. University of 

Wyoming, Laramie, Wyoming. Unpublished document. 

Wyoming Natural Diversity Database (WYNDD). 2003. Botany Comments Compiled by B. Heidel 

for C. Frank, HydroGeo, Inc., completed May 5, 2003. University of Wyoming, Laramie, 

Wyoming. Unpublished document. 

Seminoe Road Gas Development Project 7-9 
Draft Environmental Impact Statement November 2005 

Wyoming Natural Diversity Database (WYNDD). 2004. Botany Comments for C. Frank, 

HydroGeo, Inc. completed February 9, 2004. University of Wyoming, Laramie, Wyoming. 

Unpublished document. 

Wyoming Natural Diversity Database (WYNDD). 2004a. Data compilation for C. Frank, HydroGeo, 

Inc., completed February 25, 2004. University of Wyoming, Laramie, Wyoming. Unpublished 

document. 

Wyoming Natural Heritage Program. 2004. Database search for rare animal occurrences within 

the SREPA. 

7-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Chapter 8 – Glossary

A 

AAQS: Ambient Air Quality Standards (set by EPA based on Federal Clean Air Act). 

acre-foot: The amount of water or sediment volume which covers an acre of land to a depth of 

one-foot; an acre-foot is equal to 325,851 gallons or 43,560 cubic feet. 

ADT: Average daily traffic – A measure of traffic over a 24-hour period. Determined by counting 

the number of vehicles (from both directions) passing a specific point on a given road. 

aeration: The supplying of air to reach or penetrate something, such as spraying water. 

aerial: Consisting of, moving through, found, or suspended in the air. 

affect: To conduct an activity which will impact land, air, or water resources, so as to disturb the 

natural land surface. 

affected environment: A physical, biological, social, and economic environment within which 

human activity is proposed. 

air quality: Measure of the health-related and visual characteristics of the air, often derived from 

quantitative measurements of the concentrations of specific injurious or contaminating 

substances. 

alluvial: Used to describe the environment, action, and sedimentary deposits of rivers or streams. 

alluvium: Unconsolidated sedimentary material (including clay, silt, sand, gravel, and mud) 

deposited by flowing water. 

alternatives: The different means by which objectives or goals can be attained. One of several 

policies, plans, or projects proposed for decision-making. 

ambient: The environment as it exists at the point of measurement and against which changes 

(impacts) are measured. 

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ambient air quality standard: Air pollutant concentrations of the surrounding outside 

environment, which cannot legally be exceeded during fixed time intervals within specific 

geographic areas. 

anticline: An arch-shaped formation of layers of sedimentary rock folded upward by movements 

in the earth’s crust. 

APD: Application to Permit Drilling. 

aquatic: Growing, living in, frequenting, or taking place in water; in this environmental impact 

statement, used to indicate habitat, vegetation, and wildlife in fresh water. 

aquifer: A body of rock that is sufficiently permeable to conduct groundwater and to yield 

economically significant quantities of water to wells and springs. 

aquitard: A confining bed that retards but does not prevent the flow of water to or from an 

adjacent aquifer; a leaky confining bed. It does not readily yield water to wells or springs, but 

may serve as a storage unit for ground water. 

areal: The spatial extent or location. 

ARM (coast). A long, narrow inlet of water, extending inland from another body of water, such as 

an “arm of the sea.” 

artesian well: A well drilled through impermeable rocks into strata where water is under enough 

pressure to force it to the surface without pumping. 

artifact: An object made or modified by humans. 

aspect: The direction toward which a slope faces. 

attachment area: A geographic region with which National Ambient Air Quality Standards 

(NAAQS) are met; three categories of attainment are defined as Class I, Class II, and Class 

III on the basis of the level of degradation of air quality which may be permitted. 

ATV: All terrain vehicle. 

audible: Capable of being heard. 

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November 2005 Draft Environmental Impact Statement

B


BA: Biological Assessment – Refers to the information prepared by or under the direction of the 

federal agency concerning listed and proposed species and designated and proposed 

critical habitat that may be present in the action area and the evaluation of potential effects 

of the action on such species and habitat. 

BACT: Best available control technology. 

base flow: A sustained or fair-weather flow of a stream. 

baseline data: Data gathered prior to the proposed action to characterize pre-development site 

conditions. 

BCC: Birds of Conservation Concern. 

BE: Biological Evaluation – Refers to the information prepared by or under the direction of the 

Forest Service concerning listed and Regional Forester Sensitive Species that may be 

present in the action area and the evaluation of potential affects of the alternatives on such 

species and habitat. 

Best Management Practices (BMPs): Management actions that are designed to maintain water 

quality by preventative rather than corrective means. 

big game: Large mammals that are hunted, for sport or sustenance. These include animals such 

as deer, bear, elk, bobcats and mountain lions. 

biological opinion: A document that states the opinion of the USDI Fish and Wildlife Service as 

to whether or not the federal action is likely to jeopardize the continued existence of listed 

species or result in the destruction or adverse modification of critical habitat. 

BLM: Bureau of Land Management – The agency of the United States Government, under the 

Department of the Interior, responsible for administering certain public lands of the United 

States. 

bond: A sum of money which, under contract, one party pays another party under conditions that 

when certain obligations or acts are met, the money is then returned; such as after mining 

reclamation occurs. Also referred to as performance security. See “reclamation guarantee.” 

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Draft Environmental Impact Statement November 2005

BOR: Bureau of Reclamation - Agency of the United States government, under the Department of 

the Interior, responsible for managing, development, and protection of water resources in 

the interest of the American public. 

BP: Before present. 

BTU: British Thermal Unit – The amount of heat required to raise the temperature of one pound of 

water one degree Fahrenheit. 

capability: The potential of an area of land to produce resources, supply goods and services, and 

allow resource users under an assumed set of management practices at a given level of 

management intensity. Capability depends upon current conditions and site conditions such 

as climate, slope, landform, soils, and geology, as well as the application of management 

practices. 

capillarity. The action by which a fluid, such as water, is drawn up (or depressed) in small 

interstices of tubes as a result of surface tension. 

Carbon 14: A naturally radioactive isotope of carbon with atomic mass of 14 and a half-life of 

5,780 yeas, used as a tracer element and in carbon dating. 

CBM: Coalbed methane. 

CEQ: Council on Environmental Quality – An advisory council to the President of the United 

States; established by the National Environmental Policy Act of 1969. It reviews federal 

programs for their effect on the environment, conducts environmental studies, and advises 

the President on environmental matters. 

CFR: Code of Federal Regulations – A codification of the general and permanent rules published 

in the Federal Register by the executive departments and agencies of the Federal 

Government. 

cfs: Cubic feet per second – 1 cfs equals 448.33 gallons per minute. 

colluvium: Soil material or rock fragments moved down slope by gravitational force in the form of 

creep, slides, and local wash. 

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November 2005 Draft Environmental Impact Statement

concern: A point, matter, or question raised by management or the public that must be addressed 

in the planning process. 

cone of depression (or drawdown cone): The groundwater drawdown surrounding a pumped 

well. 

confined aquifer: In hydrogeology where groundwater pressure is controlled by a confining layer 

and not atmospheric pressure. 

confining bed: A body of impermeable or distinctly less permeable material stratigraphically 

adjacent to one or more aquifers. 

confining layer: Geologic layer that prevents movement of fluids such as groundwater. 

consumptive use: A use, which lessens the amount of water available for another use. Water 

uses normally associated with man’s activities, primarily municipal, industrial, and irrigation 

uses that complete water supplies. Water removed from available supplies without direct 

return to a water resource system, for uses such as manufacturing, agriculture, and food 

preparation. A non-consumptive use would be one such as boating or swimming. Combined 

amounts of water needed for transpiration by vegetation and for evaporation from adjacent 

soil, snow, or intercepted precipitation. 

consumptive water use: Total amount of water used by vegetation, man’s activities, and 

evaporation of surface water. 

critical habitat: Defined in Section 3, (5)(A) of the Endangered Species Act (ESA) as: (1) The 

specific areas within the geographical area occupied by the species at the time it is listed, 

on which are found those physical and biological features essential to the conservation of 

the listed species and which may require special management considerations for protection; 

and (2) specific areas outside the geographical area occupied by a species at the time it is 

listed upon a determination by the Secretary of the Department of the Interior that such 

areas are essential for the conservation of the species. These areas have been legally 

designated via Federal Register notices. 

crucial winter range: Those areas, which, during the winter months, determine a population’s 

ability to maintain and reproduce itself at a certain level over the long term. 

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Draft Environmental Impact Statement November 2005

cultural resources: The remains of sites, structures, or objects used by humans in the past, 

historic or prehistoric. More recently referred to as heritage resources. 

cumulative effects or impacts: Cumulative effect or impact is the impact on the environment, 

which results from the incremental impact of the action when added to other past, present, 

and reasonable foreseeable future actions, regardless of what agency (federal or nonfederal) or person undertakes such other actions. Cumulative impacts can result from 

individually minor but collectively significant actions taken place over a period of time (40 

CFR 1508.7 – these regulations use effects and impacts synonymously). For example, the 

impacts of a proposed timber sale and the development of a mine together result in 

cumulative impacts. 

D 

dam: A barrier built across a watercourse to impound or divert water. A barrier that obstructs, 

directs, retards, or stores the flow of water. Usually built across a stream. A structure built to 

hold back a flow of water. 

DB: Decibel – A unit of expressing the relative intensity (loudness) of sound (decibel or dBA), 

weighted along the audible frequencies. 

decision-makers: The agencies, or designated representatives within the agencies, who must 

make the final decisions based upon the information presented in this Environmental Impact 

Statement. 

decommissioning: Suspension and/or closure of operations and possible removal of facilities. 

demography: Statistical study of the characteristics of human populations with reference to size, 

density, growth, distribution, migration, and effect on social and economic conditions. 

density: The number of individuals in a given area. Expressed per unit area. 

deposit: A natural accumulation, such as precious metals, minerals, coal, gas, oil, etc., that may 

be pursued for its intrinsic value; coal deposit. 

DEQ: Department of Environmental Quality (Wyoming). 

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November 2005 Draft Environmental Impact Statement

desorption: The action or process of releasing an absorbed substance from something, for 

example, gas from rocks. 

detection limit: The lowest concentration of a chemical that can be reliability reported to be 

different from zero concentration. Various analytical instrumentation has different detection 

limits. 

dewatering: The removal and control of ground water from pores and other open spaces in rock 

or soil formations. 

dilution: The act of mixing or thinning, and therefore decreasing a certain strength or 

concentration. 

dip (structural geology): The angle that a structural surface, e.g. a bedding or fault plane, 

makes with the horizontal, measured perpendicular to the strike of the structure and in a 

vertical plane. 

direct effects: The effects that result from an action and occur at the same time and place as the 

action. 

direct impacts: Impacts which are caused b the action and occur at the same time and place. 

Directional drilling: Used to guide a well to a predefined target. 

discharge: See water discharge. 

domestic water use: Water for household purposes, such as drinking, food preparation, bathing, 

washing clothes and dishes, flushing toilets, and watering lawns and gardens. 

DOT: Department of Transportation (Federal). 

Draft EIS: The draft state of environmental effects which is required for major federal actions 

under Section 102 of the National Environmental Policy Act, and released to the public and 

other agencies for comment and review. 

drainage area: The area which drains to a particular point on a river or stream. The drainage area 

of a stream at a specified location is that area, measured in a horizontal plane, enclosed by 

a topographic divide from which direct surface runoff from precipitation normally drains by 

gravity into the stream above the specified point. 

Seminoe Road Gas Development Project 8­7
Draft Environmental Impact Statement November 2005

drawdown: The drop in hydrostatic pressure in an aquifer due to pumping of a well. 

drilling: Mechanical process of boring into the earth’s surface to gather subsurface geologic, 

physical, or chemical data to determine the location, quantity, or quality of the natural 

mineral deposit on an area, including holes drilled for use as water wells. 

drought: Climactic condition in which there is insufficient soil moisture available for normal 

vegetative growth. A prolonged period of below-average precipitation. 

droughty soil conditions: Dry soils caused by the lack of rain or water; soils affected by the 

prolonged dryness of weather, which prevents or inhibits plant growth. 

E 

EA: Environmental Assessment - A NEPA compliance document used to determine if an action 

would have a significant effect on the human environment. If not, a finding of no significant 

impact (FONSI) is written. If so, an environmental impact statement (EIS) is written. 

effects: “Effect” and “impact” are synonymous as used in this document. Environmental changes 

resulting from a proposed action. Included are direct effects, which are caused by the action 

and occur at the same time and place, and indirect effects, which are caused by the action 

and are later in time or further removed in distance, but which are still reasonably 

foreseeable. Indirect effects may include growth-inducing effects and other effects related to 

induced changes in the pattern of land use, population density, or growth rate, and related 

effects on air and water and other natural systems, including ecosystems. 

EIS: Environmental Impact Statement – An analytical document prepared under the National 

Environmental Policy Act that portrays potential impacts to the environment of a proposed 

action and its possible alternatives. An EIS is developed for use by decision-makers to 

weigh the environmental consequences of a potential decision. 

employment: Labor input into a production process, measured in the number of person-years or 

jobs. A person-year is approximately 2,000 working hours by one person working yearlong 

or by several persons working seasonally. The number of jobs required to produce the 

output of each sector. A job may be one week, one month, or one year. 

8­8 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

endangered species: Any species of animal or plant that is in danger of extinction throughout all 

or a significant portion of its range. Plant or animal species identified by the Secretary of the 

Interior or endangered in accordance with the 1973 Endangered Species Act. 

environment: The physical conditions that exist within the area that will be affected by a proposed 

project, including land, air, water, minerals, flora, fauna, ambient noise, and objects of 

historical or aesthetic significance. The sum of all external conditions that affect an 

organism or community to influence its development or existence. 

EPA: Environmental Protection Agency – An agency of the Executive Branch of the Federal 

Government which has responsibility for environmental matters of national concern. 

ephemeral stream: A stream or portion of a stream that flows only in direct response to 

precipitation or snow melt. Such flow is usually of short duration. 

epoch: A term used to designate a length of geologic time. 

erosion: The wearing away of the land surface by running water, wind, ice, or other geologic 

agents, including gravitation creep. 

ERP: Emergency Response Plan. 

entrained: In hydrogeology where fluid is entrapped in porous rock, sediment, or soil. 

evaporation: Water vapor losses from water surfaces, sprinkler irrigation, and other related 

factors. Loss of water to the atmosphere. The process by which water is changed from a 

liquid into a vapor. Water from land areas, bodies of water, and all other moist surfaces is 

absorbed into the atmosphere as a vapor. 

evapotranspiration: The quality of water transpired by plants or evaporated from adjacent soil 

surfaces in a specific time period. Usually expressed in depth of water per unit area. The 

combined processes of evaporation and transpiration. 

exploration: The search for economic deposits of minerals, gas, oil or coal through the practices 

of geology, geochemistry, geophysics, drilling, shaft sinking, and/or mapping. 

Seminoe Road Gas Development Project 8­9
Draft Environmental Impact Statement November 2005

F 

fault: Displacement of rock along a sheer surface or linear plane. 

feasible: Capable of being accomplished in a successful manner within a reasonable period of 

time, taking into account economic, environmental, legal, social, and technological factors. 

Final EIS: Means a detailed written statement as required by Section 102(2)(C) of the National 

Environmental Policy Act (40 CFR 1508.11). It is a revision of the Draft Environmental 

Impact Statement to include public and agency comments to the draft. 

Finding of No Significant Impact (FONSI): A NEPA compliance document which affirms that an 

environmental assessment found that alternatives were evaluated and a proposed action 

would have no significant impact on the human environment. 

fisheries habitat: Streams, lakes, and reservoirs that support fish populations. 

fishery: All activities related to human harvest of a fisheries resource. 

FLPMA: Federal Land Policy and Management Act. 

fugitive dust: Dust particles suspended randomly in the air, usually from road travel, excavation, 

and /or rock loading operations. 

full pool: Volume of water in a reservoir at normal water surface. The reservoir level that would 

be attained when the reservoir is fully utilized for all project purposes, including flood 

control. 

G 

game species: Any species of wildlife or fish for which season and bag limits have been 

prescribed and which are normally harvested by hunters, trappers, and fishermen under 

state or federal laws, codes and regulations. 

generator: Machine that converts mechanical energy into electrical energy. 

8­10  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

geochemistry: The study of the distribution and amounts of the chemical elements in minerals, 

ores, rocks, soils, water, and the atmosphere, and the study of the circulation of the 

elements in nature, on the basis of the properties of their atoms and ions. 

geohydrology: Refers to the hydrologic or flow characteristics of subsurface waters. Often 

interchangeable with hydrogeology. 

geologic basin A large, sometimes regional scale circular outcrop of rock I which strata dip 

inward toward the center. In geography, a broad area of land drained by a single river and 

its tributaries, or draining into a lake 

geology: The science that deals with the physical history of the earth, the rocks of which it is 

comprised, and the physical changes which the earth has undergone or is undergoing. 

geomorphology: Geological study of the configuration, characteristics, origin, and evolution of 

landforms and earth features. 

gpd, ph, gpm: Gallons per day, gallons per hour, gallons per minute. 

gravel surfacing: Layer of gravel spread over an area intended for vehicular or personnel traffic, 

such as roads and parking lots. 

Ground water: Water found beneath the land surface in the zone of saturation below the water 

table. 

growth media: All materials, including topsoil, specified soil horizons, vegetative debris, and 

organic water, which are classified as suitable for stockpiling and/or reclamation. 

guidelines: An indication or outline of policy or conduct; (i.e., any issuance that assists in 

determining the course of direction to be taken in any planned action to accomplish a 

specific objective). 

gullying: Small-scale stream erosion. 

Guzzler: A stock water device used to capture and store rainfall. 

Seminoe Road Gas Development Project 8­11
Draft Environmental Impact Statement November 2005

H 

habitat: A natural environment of a plant or animal, including all biotic, climatic, and soil 

conditions, or other environmental influences affecting living conditions. The place where an 

organism lives. 

habitat capability: The estimated ability of an area, given existing or predicted habitat conditions, 

to support a wildlife, fish, or plant population. It is measured in terms of potential population 

numbers. 

habitat effectiveness: Degree to which a physical wildlife habitat is free from man-caused 

disturbances, and therefore attractive to wildlife occupancy. 

headcut. A vertical face or drop on the bed of a stream channel, occurring at a knickpoint. 

herbicide: A compound, a man-made organic chemical used to kill or control plant growth. 

HMMP: Hazardous Materials Management Plan. 

Holocene: An epoch of the Quaternary period, from the end of the Pleistocene, approximately 

8,000 – 10,000 years ago, to the present time. 

horizontal drilling: A process of guiding a well to a predefined rock strata (like a coal seam), 

then realigning the well to track within or parallel to the strata. 

human environment: Natural and physical environment and the relationship of people with that 

environment, including combinations of physical, biological, cultural, social, and economic 

factors in a given area. 

hydraulic conductivity: A measure of the ability of rock or soil to permit the flow of groundwater 

under a pressure gradient; permeability. 

hydraulic fracturing: A general term, for which there are numerous trade or service names, for 

the fracturing of rock usually in an oil or gas reservoir, but pumping in water (or other fluid) 

and sand under high pressure. The purpose is to produce artificial openings in rock to 

increase permeability. 

8­12 Seminoe Road Gas Development Project
I 

November 2005 Draft Environmental Impact Statement

hydric: Set of a habitat that has or required abundant moisture. In the case of soils, hydric means 

soils that are saturated with water or moisture. 

hydrofracture: Involves injecting a sand/water slurry mixture under very high pressure through 

the injection well borehole into the target receiving formation creating open fractures, thus 

increasing the permeability of the formation. This practice allows for more water to be 

injected into the formation at less pressure. 

hydrogeology: The science that deals with sub-surface waters (groundwater) and with related 

geologic aspects of surface waters (springs and seeps). 

hydrologic system: All physical factors, such as precipitation, stream flow, snowmelt, 

groundwater, etc., that effects the hydrology of a specific area. 

hydrology: Scientific study of water in nature: it’s properties, distribution and behavior. The 

science that treats the occurrence, circulation properties, and distribution of the waters of 

the earth and their relation to the environment. The science dealing with the properties, 

distribution and flow of water on or in the earth. 

hydrophytic vegetation: Vegetation growing in water, either submerged, emergent or floating. 

Vegetation that requires large quantities of water for its growth. 

hydrostatic pressure: The pressure exerted by water. The hydrostatic pressure of ground water 

is generally due to the weight of water at higher levels in the zone of saturation. 

ID Team: Interdisciplinary Team – The interdisciplinary team is comprised of a group of personnel 

with different training assembled to solve a problem or perform a task. The team will 

consider problems collectively, rather than separate concerns along disciplinary lines. The 

interaction is intended to insure systematic, integrated consideration of physical, biological, 

economic, environmental design arts and sciences. 

impermeable: Property of a substance that inhibits passage of fluids through its mass. 

impoundment: The collection and confinement of water in a reservoir or other storage area. 

Seminoe Road Gas Development Project 8­13
Draft Environmental Impact Statement November 2005

increment: The amount of change from an existing concentration or amount, such as air pollutant 

concentrations. 

indirect impacts: Impacts which are caused by the action but are later in time or farther removed 

in distance, although still reasonably foreseeable. 

infiltration: The movement of water or some other fluid into the soil through pores or other 

openings. 

informal consultation: An optional process that includes all discussions, correspondence, etc., 

between the USDI Fish and Wildlife Service and another federal agency or the designated 

non-federal representative prior to formal consultation, if required. 

infrastructure: The underlying foundation or basic framework; substructure of a community (i.e., 

schools, police, fire services, hospitals, water and sewer systems). 

interdisciplinary approach: Using a variety of expertise to prepare analyses which ensure the 

integrated use of natural and social sciences and the environmental design arts. An 

interdisciplinary team is used as no single scientific discipline can adequately identify and 

resolve problems. 

Interdisciplinary Team (IDT): A group of specialists assembled as a cohesive team with frequent 

interactions to solve a problem or perform a task. Note: Interdisciplinary teams are 

assembled because commonly, no one scientific discipline is sufficiently broad to 

adequately analyze a problem or proposed action. 

intermittent stream: A stream that runs water in most months, but does not contain water yearround. 

interstice: An opening or space, as in a rock or soil. 

irretrievable: Commitments that are lost for a period of time. 

irreversible: Commitments that cannot be reversed, except perhaps in the extreme long term. 

irrigation: Act of supplying dry land with water in order to grow crops or other plants. Application 

of water to lands for agricultural purposes. 

8­14 Seminoe Road Gas Development Project
L 

November 2005 Draft Environmental Impact Statement

isotope: Either of two or more forms of a chemical element with the same atomic number but 

different numbers of neutrons. 

issue: A point, matter, or question of public discussion or interest to be addressed or decided 

through a planning process. 

J 

jeopardy or jeopardize the continued existence of: Means to engage in an action that 

reasonably would be expected, directly or indirectly, to reduce appreciably the likelihood of 

both the survival and recovery of a listed species in the wild by reducing the reproduction, 

numbers, or distribution of that species. A jeopardy opinion would result in the USDI Fish 

and Wildlife Service developing reasonable and prudent alternatives for the proposed 

action. 

jurisdictional wetland: A wetland area delineated and identified by specific technical criteria, field 

indicators and other information for purposes of public agency jurisdiction. The U.S. Army 

Corps of Engineers regulate “dredging and filling” activities associated with jurisdictional 

wetlands. Other federal agencies that can become involved with matters that concern 

jurisdictional wetlands include the USDI Fish and Wildlife Service, the Environmental 

Protection Agency, and the Natural Resource Conservation Service. 

K 

kilovolt (kV): 1,000 volts. 

knickpoint. Any interruption or break of slope, especially, a point of an abrupt change or inflection 

in the longitudinal profile of a stream or of its valley. 

Lanceolate: spear-shaped, or shaped like a lance head, such as a leaf or prism that is much 

longer than broad, widening above the base and tapering to a point at the apex. 

land management: The intentional process of planning, organizing, programming, coordinating, 

directing, and controlling land use actions. 

Seminoe Road Gas Development Project 8­15
Draft Environmental Impact Statement November 2005

land status: The ownership status of lands. 

lead agency: In NEPA (40 CFR 1501.5), the agency(s) with main responsibility for complying with 

NEPA procedural requirements, such as supervising the preparation of an Environmental 

Impact Statement. 

lease: A document through which interests are transferred from one party to another, subject to 

certain rights, obligations, and considerations. 

listed species: Species that are listed as threatened or endangered under the Endangered 

Species Act of 1973 (as amended). 

lithic: Pertaining to or made of stone, e.g. “lithic artifacts.” 

long-term impacts: Impacts that normally result in permanent changes to the environment. An 

example is a topographic change resulting from tailings disposal in a drainage. Each 

resource, by necessity, may vary in its delineation of long-term. 

M 

macropore. A pore too large to hold water by capillarity. 

management activity: An activity of man imposed on a landscape for the purpose of harvesting, 

traversing, transporting, or replenishing natural resources. 

management area: An area with similar management objectives and a common management 

prescription. 

management direction: A statement of multiple-use and other goals and objectives, and the 

associated management prescriptions, and standards and guidelines for attaining them. (36 

CFR 219.3) 

map: Usually a 2-dimensional representation of all or part of the earth’s surface showing selected 

natural or manmade features or data, preferably constructed on a definite projection with a 

specified scale. 

MBTA: Migratory Bird Treaty Act. 

8­16  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

mean: A statistical value calculated by dividing the sum of a set of sample values by the number 

of samples. Also referred to as the arithmetic mean or average. 

Micron: A particle having a diameter of one millionth of a meter. 

migratory: Moving from place to place, daily or seasonally. 

migration: Migration includes: (a) avoiding the impact altogether by not taking a certain action or 

parts of an action; (b) minimizing impacts by limiting the degree or magnitude of the action 

and its implementation; (c) rectifying the impact by repairing, rehabilitating, or restoring the 

affected environment; (d) reducing or eliminating the impact over time by preservation and 

maintenance of operations during the life of the action; and, (e) compensating for the impact 

by replacing or providing substitute resources of environments (40 CFR 1508.20). 

MOA: Memorandum of Agreement. 

monitoring and evaluation: A watching, observing or checking, in this instance, a testing of 

specific environmental parameters and of project waste streams for purposes of comparing 

with permit stipulations, pollution control regulations, mitigation plan goals, etc. The periodic 

evaluation of management practices on a sample basis to determine how well objectives 

have been met. 

MOU: Memorandum of Understanding – Usually documenting an agreement reached amongst 

federal agencies. 

MSDA: Material Safety Data Sheet. 

mulch: Material spread on the ground to reduce soil erosion and evaporation of water. Any 

substance spread or allowed to remain on the soil surface to conserve soil moisture and 

shield soil particles from the erosive forces of raindrops and runoff. 

multiple use: The management concepts under which National Forest and BLM lands are 

managed. The management of the lands and their various resource values so they are 

utilized in the combination that will best meet the present and future needs of the American 

people. 

Seminoe Road Gas Development Project 8­17
Draft Environmental Impact Statement November 2005

N 

NAAQS: National Ambient Air Quality Standards. 

NADP: National Atmospheric Deposition Program. 

NEPA (National Environmental Policy Act): An act declaring a national policy which encourages 

productive and enjoyable harmony between humankind and the environment, promotes 

efforts which will prevent or eliminate damage to the environment and biosphere and 

stimulate the health and welfare of humanity, enriches the understanding of the ecological 

systems and natural resources important to the nation, and establishes a Council on 

Environmental Quality. 

NPDES (National Pollution Discharge Elimination System): A program authorized by Sections 

3.18, 402 and 405 of the Clean Water Act, and implemented by regulations 40 CFR 122. 

NPDES program requires permits for the discharge of pollutants from any point source into 

Waters of the United States. 

NRHP (National Register of Historic Places): A federally maintained register of districts, sites, 

buildings, structures, architecture, archaeology and culture. 

NRCS: Natural Resources Conservation Service. 

NSPS (New Source Performance Standards): Standards set by EPA defining the allowable 

pollutant discharge (air and water) and applicable pollution control for new facilities; by 

industrial category (Clean Air Act and Clean Water Act). 

NEPA Process: Measures necessary to comply with the requirements of Section 2 and Title I of 

the National Environmental Policy Act. 

non-consumptive water uses: Water uses that do not substantially complete water supplies, 

including swimming, boating, water skiing, fishing, maintenance of stream related fish and 

wildlife habitat, and hydro power generation. 

non-game species: Animal species which are not hunted, fished, or trapped. 

NOx: Nitrogen oxides – A product of vehicle exhaust. 

8­18  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

noxious weed: (from the 1974 Federal Noxious Weed Act) any living stage, such as seeds and 

reproduction parts, of any parasitic or other plant of a kind, which is of foreign origin, is new 

to or not widely prevalent in the United States, and can directly or indirectly injure crops, 

other useful plants, livestock, or poultry or other interests of agriculture, including irrigation, 

or navigation, or the fish or wildlife resources of the United States or the public health. 

O 

O & M: Operations and maintenance. 

objective: A concise, time-specific statement of measurable planned results that respond to preestablished goals. An objective forms the basis for further planning to define the precise 

steps to be taken and the resources to be used in achieving identified goals. 

observation well: A whole used to observe ground water surface at atmospheric pressure within 

soil or rock. 

organism: Any form of animal or plant life. 

OSHA: Occupational Safety and Health Administration. 

overland flow: That part of surface runoff flowing overland surfaces toward stream channels. 

P 

parent material: The unconsolidated material (mineral and/or organic) from which soils develop.


particulates: Small particles suspended in the air or generally considered pollutants.


peak flow: Maximum instantaneous flow in a specified period of time.


pedestalling: Undercutting rock or soil as a result of wind erosion and abrasion.


pedon: The smallest unit or volume of soil that represents or exemplifies all the horizons of a soil


profile. The term is part of the soil classification system of the National Cooperative Soil 

Survey. 

perennial stream: A stream that flows year-round. 

Seminoe Road Gas Development Project 8­19
Draft Environmental Impact Statement November 2005

performance bond: See “reclamation guarantee.” 

permeability: The property or capacity of a porous rock, sediment, or soil for transmitting a fluid; 

it is a measure of the relative ease of fluid flow under unequal pressure. 

pH: Symbol for the negative common logarithm of the hydrogen ion concentration (acidity) of a 

solution. The pH of 7 is considered neutral. A pH number below indicates acidity, and a pH 

value above 7 indicate alkalinity or a base. 

piezometer: A device for measuring moderate groundwater pressure. 

piezometric surface: Any imaginary surface coinciding with the hydraulic pressure level of the 

water in a confined aquifer, or the surface representing the static head of groundwater and 

defined by the level to which water will rise in a well. A water table is a particular piezometric 

surface. 

planning records: The body of information documenting the National Environmental Policy Act 

decisions and activities which result from the process of developing environmental 

documents; also known as an administrative record. 

plant communities: A vegetation complex unique in its combination of plants which occurs in 

particular locations under particular influences. A plant community is a reflection of 

integrated environmental influences on the site such as soils, temperature, elevation, solar 

radiation, slope aspects, and precipitation. 

playa: A dry, vegetation-free, flat area at the lowest part of an undrained basin, underlain by 

stratified clay, silt or sand, and commonly by soluble salts. The term is also applied to the 

basin containing an expanse of playa, which may be marked by ephemeral lakes. 

Pleistocene: An epoch of the Quaternary period, starting about two to three million years ago and 

lasting until the start of the Holocene some 8,000 – 10,000 years ago. 

PM10: Particulates of 10 microns in size or less, usually describing a source of air quality 

degradation. 

point source: Stationary sources of potential pollutants. 

policy: A guiding principle upon which is based a specific decision or set of decisions. 

8­20  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

pollution: Human-caused or natural alteration of the physical, biological and radiological integrity 

of water, air, or other aspects of the environment producing undesired effects. 

potable water: Suitable, safe, or prepared for drinking. 

potentiometric surface: Surface to which water in an aquifer would rise by hydrostatic pressure. 

ppm: Parts per million. 

precipitation event: A quantity of water resulting from drizzle, rain, snow, sleet, or hail in a limited 

period of time. It may be expressed in terms of recurrence, interval, and duration. 

prehistoric: Relating to the times just preceding the period of recorded history. 

project: The whole of an action, which has a potential for resulting in a physical change in the 

environment. An organized effort to achieve an objective identified by location, timing, 

activities, outputs, effects, and time period and responsibilities for executions. 

Proponent: Dudley & Associates, LLC. 

proposed action: A description of the project as proposed by a project proponent in a plan of 

operations. 

PSD: Prevention of Significant Deterioration – A specific permit procedure established in the 

Clean Air Act, as amended, used to ensure that economic growth occurs in a manner 

consistent with the protection of public health; preservation of air quality related values in 

national special interest areas; the opportunity for informed public participation in the 

decision-making process. 

public land: Land administered by the Bureau of Land Management, Forest Service, or other 

government agencies. 

public participation: Meetings, conferences, seminars, workshops, tours, written comments, 

responses to survey questionnaires, and similar activities designed and held to obtain 

comments from the public about planning. 

public scoping: Giving the public the opportunity for oral or written comments concerning the 

intentions, activity, or influence of a project on an individual, the community, and/or the 

environment. 

Seminoe Road Gas Development Project 8­21
Draft Environmental Impact Statement November 2005

pump: Mechanical device, components or pieces of equipment, that are powered by an engine or 

motor to create the flow of a fluid or viscous material. 

pumping: Mechanical transfer of fluids. 

Q 

qualitative: Having to do with quality or qualities. Descriptive of kind, type or direction, as 

opposed to size, magnitude or degree. 

quantitative: Having to do with quantity, capable of being measured. Descriptive of size, 

magnitude or degree. 

Quaternary: A geological time period beginning approximately two to three million years ago and 

extending to the present. It consists of two grossly unequal epochs; the Pleistocene, up to 

about 8,000 – 10,000 years ago and the Holocene since that time. 

R 

raptor: Bird of prey, including eagles, hawks, falcons, and owls. 

recharge: The processes involved in the absorption and addition of water to the zone of 

saturation. 

recharge area: An area in which water is absorbed that eventually reaches the zone of saturation 

in one or more aquifers. 

recharge rate: The quantity of water per unit time that replenishes or refills an aquifer. 

reclamation: Returning disturbed land to a productive form. 

reclamation guarantee: A binding commitment payable to a government agency in the event that 

decommissioning and reclamation of an operation is not completed according to an 

approved plan or permit. See “bond.” 

reservoir: A body of water impounded by a dam and in which water can be stored. Artificially 

impounded body of water. Any natural or artificial holding area used to store, regulate or 

8­22 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

control water. Body of water, such as natural or constructed lake, in which water is collected 

and stored for use. 

resident: A species, which is found in a particular habitat for a particular time period (i.e., winter 

resident, summer resident, year-round) as opposed to those found only when passing 

through on migration. 

rill: A very small eroded channel. 

riparian: A type of ecological community that occurs adjacent to streams and rivers and is directly 

influenced by water. It is characterized by certain types of vegetation, soils, hydrology, and 

fauna and requires free or unbound water or conditions more moist than that normally found 

in the area. 

riparian zone: Terrestrial areas where the vegetation and microclimate are influenced by 

perennial and/or intermittent water, associated high water tables and soils which exhibit 

some wetness characteristics; this habitat is transitional between true bottom land wetlands 

and upland terrestrial habitats. 

riprap: A layer of angular rock placed together to prevent erosion on embankments and 

engineered channels. 

riverine: Riparian; pertaining to a riverbank. 

RMP: Resource Management Plan. 

ROD: Record of Decision – A document separate from, but associated with, and Environmental 

Impact Statement which states the decision, identifies alternatives, specifying which were 

environmentally preferable, and states whether all practicable means to avoid 

environmental harm from the alternative have been adopted, and if not, why not (40 CFR 

1505.2). 

ROW: Right-of-way. 

runoff: Precipitation that is not retained on the site where it falls, not absorbed by the soil; natural 

drainage away from an area. 

Seminoe Road Gas Development Project 8­23
Draft Environmental Impact Statement November 2005

S 

saline: The condition of containing dissolved or soluble salts. Saline soils are those whose 

productivity is impaired by high soluble salt content. Saline water is that which would impair 

production if used to irrigate sensitive crops without adequate leaching to prevent soil 

salinization. 

saline sodic land: Soil that contains soluble salts in amounts that impair plant growth but not an 

excess of exchangeable sodium. 

saline water: Water that contains more than 1,000 milligrams per liter of dissolved solids. 

salinity: The relative concentration of dissolved salts, usually sodium chloride, in a given water 

supply. A measure of the concentration of dissolved mineral substances in water. 

saturated soils: Soil condition during which all the spaces between soil particles are filled with 

water. 

scoping process: A part of the National Environmental Policy Act process; early and open 

activities used to determine the scope and significance of the issues, and the range of 

actions, alternatives, and impacts to be considered in an Environmental Impact Statement 

(40 CFR 1501.7). 

scour: Erosion in a stream bank, particularly if caused or increased by channel changes. 

sediment: Any finely divided organic and/or mineral matter deposited by air or water in nonturbulent areas. Unconsolidated solid material that comes from weathering of rock and is 

carried by, suspended in, or deposited by water or wind. 

sedimentary: Term used to describe rocks formed from material, including debris of organic 

origin, deposited as sediment by water, wind or ice and then consolidated by pressure. 

sediment load: The quantity of sediment, measured in dry weight or by volume, transported 

through a stream cross-section in a given time. Sediment discharge consists of both 

suspended load and bedload. 

sediment yield: The quantity of sediment transported through a stream cross-section in a given 

time. 

8­24 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

seismicity: The phenomenon of earth movements. 

semi confined aquifer: In hydrogeology where groundwater pressure is partially controlled by a 

confining layer and partially by atmospheric pressure. 

sensitive species: Plant or animal species which are susceptible or vulnerable to activity impacts 

or habitat alterations. Those species that have appeared in the Federal Register as 

proposed for classification or are under consideration for official listing as endangered or 

threatened species, that are on an official state list, or that are recognized by the BLM as 

needing special management to prevent placement on federal or state lists. 

sheetflow. See sheetwash. 

sheetwash: An overland flow of downslope movement of water – taking the form of a thin, 

continuous film over relatively smooth soil or rock surface and not concentrated into 

channels larger than rills (also referred to as sheet flow). 

SHPO: State Historic Preservation Office. 

short-term impacts: Impacts occurring during project construction and operation, and normally 

ceasing upon project closure and reclamation. Each resource, by necessity, may vary in its 

definition of short-term. 

significant: Requires consideration of both context and intensity. Context means that the 

significance of an action must be analyzed in several contexts such as society as a whole, 

and the affected region, interests, and locality. Intensity refers to the severity of impacts. 

The severity of an impact should be weighted along with the likelihood of its occurrence. 

SO2: Sulfur oxides, including sulfur dioxide (SO2). A product of vehicle tailpipe emissions. 

socioeconomic: Pertaining to, or signifying the combination or interaction of social and 

economic factors. 

Sodium Absorption Ratio (SAR): The ratio of the ions of sodium, calcium, and magnesium. High 

SAR levels can damage soil structure by binding up clay molecules and reducing water 

infiltration. 

soil horizon: A layer of soil material approximately parallel to the land surface differing from 

adjacent genetically related layers in physical, chemical, and biological properties. 

Seminoe Road Gas Development Project 8­25
Draft Environmental Impact Statement November 2005

solid waste: Garbage, refuse, and/or sludge from a waste treatment plant, water supply 

treatment plant, or air pollution control facility, and other discarded material, including solid, 

liquid, semi-solid, or contained gaseous material resulting from industrial, commercial, 

mining, agricultural, and community activities. 

sound level (dBA): The sound pressure level in decibels as measured on a sound level meter 

using the A-weighing filter network. The A-weighing filter de-emphasizes the very low and 

very high frequency components of the sound in a manner similar to the responses of the 

human ear and gives good correlation with subjective reactions to noise. 

SPCC: Spill Prevention Control and Countermeasure Plan – A plan which the EPA requires 

having on file within six months of project inception. It is a contingency plan for avoidance of 

containment of, and response to hazardous materials spills or leaks. 

special-use authorization: A permit, term permit, lease, or easement that allows occupancy or 

use. 

stable isotope: In physics, an isotope incapable of becoming a different isotope or element by 

radioactive decay. Often used in age dating of water. 

standard: A model, example, or goal established by authority, custom, or general consent as a 

rule for the measurement of quantity, weight, extent, value or quality. 

strata (stratum): Distinctive layers of stratified rock. A layer of sedimentary rock, visually 

separable from other layers above and below. 

stream: Natural water course containing water at least part of the year. The type of runoff where 

water flows in a channel. 

stream gradient: The rate of fall or loss of elevation over the physical length of a segment or total 

stream usually express in ft/ft (%). 

strike (structural geology): The direction or trend taken by a structural surface, e.g. a bedding or 

fault plane, as it intersects the horizontal. A strike is at right angles to the line of dip. 

structure (structural geology): The general disposition, attitude, arrangement or relative 

positions of the rock masses of a region or area. Structure can be influenced by 

deformational processes such as faulting and folding. 

8­26  Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

submersible pump: Pump designed to be totally submerged in the fluid it is pumping. 

Submersible pumps eliminate suction lift limitations, loss of prime, the need for suction 

hose, and noise. 

subsidence: The sudden sinking or gradual downward settling of the ground’s surface. 

substantive comment: A comment that provides factual information, professional opinion, or 

informed judgment germane to the action being proposed. 

succession: The gradual supplanting of one community of plants by another. 

surface runoff: Precipitation, snowmelt, or irrigation in excess of what can infiltrate the soil 

surface and be stored. 

suspended load (suspended sediment): Sediment that is supported by the upward components 

of turbulence in a stream and that stays in suspension for an appreciable length of time. 

T 

TDS: Total Dissolved Solids – Any finely divided materials (with a diameter smaller than a few 

hundred micrometers) suspended in liquids such as water. 

terrace deposits: Sediments deposited along stream banks at high and low flow periods. 

terrestrial: Of or relating to the earth, soil, or land; an inhabitant of the earth or land. 

threatened species: Those plant or animal species likely to become endangered species 

throughout all or a significant portion of their range within the foreseeable future. 

third-party contractor: An independent firm, usually contracted by a government agency, to 

perform work related to a proposed action or another organization; due to the financial and 

contractual arrangements governing such relationships, the third-party contractor has not 

financial or other interest in the decision to be reached on the project. 

tiering: The coverage of general matters in a broad NEPA document with subsequent narrowly 

focused documents; helps to eliminate repetitive discussions and allows the site-specific 

documents to focus on specific issues. 

Seminoe Road Gas Development Project 8­27
Draft Environmental Impact Statement November 2005

topography: A configuration of a surface including its relief, elevation, and the portion of its 

natural and human-created features. 

tpd: Tons per day. 

tph: Total petroleum hydrocarbons. 

transient equation: Time dependent mathematical equation that solves a problem for various 

time segments. 

transmission: The act or process of transporting electric energy in bulk. 

transmission line: Facility for transmitting electric energy at high voltage from one point to 

another point. 

transmissivity: The ability of an aquifer to transmit water. 

transpiration: The process by which water and plants is transferred into water vapor in the 

atmosphere. Evaporation of water through the leaves of plants. 

Tritium: A radioactive isotope of hydrogen occurring naturally in trace amounts and having atomic 

mass 3 and a half-life of 12.3 years. An isotope deposited by surface testing of nuclear 

weapons and used as a tracer in age dating of water. 

TSP: Total suspended Particulates – Any finely divided material (solid or liquid) that is airborne 

with an aerodynamic diameter smaller than a few hundred micrometers. 

TSS: Total suspended solids – As it applies to sediments in streams. 

turbidity: Reduced water clarity resulting from the presence of suspended matter. 

two-track road: a lightly-used road formed in native vegetation by vehicles such as pick-up 

trucks. 

U 

unavoidable effects: Those effects which would occur from a project but cannot be eliminated or 

minimized by management requirements and mitigation measures. 

8­28  Seminoe Road Gas Development Project
V 

November 2005 Draft Environmental Impact Statement

unconfined aquifer: An aquifer containing water that is not under pressure; the water level in a 

well is the same as the water table outside the well. An aquifer that discharges and 

recharges with an upper surface that is the water table. 

underground injection: Injection of fluids under high pressure through a well into a subsurface 

geologic horizon. 

unconsolidated: In geology, not combined into a single or solid mass. 

USDI: United States Department of the Interior. 

USFWS: United States Fish and Wildlife Service – United States Department of the Interior. 

USGS: United States Geological Survey – United States Department of the Interior. 

vertical conductance: The property or capacity of porous rock, sediment, or soil for transmitting 

a fluid vertically up or down typically between different strata. 

visitor use: Visitor use of recreation and wilderness resource for inspiration, stimulation, solitude, 

relaxation, education, pleasure or satisfaction. 

volt (V): The unit of measurement of electromotive force. It is equivalent to the force required to 

produce a current of 1 ampere through a resistance of 1 OHM. 

VRM: Visual Resource Management. 

W 

WAAQS: Wyoming Ambient Air Quality Standards.


WAPA: Western Area Power Administration.


water depletion: To permanently remove water from a system for a specific use. Loss of water


from stream, river, or basin resulting from consumptive use. 

Seminoe Road Gas Development Project 8­29
Draft Environmental Impact Statement November 2005

water discharge: The volume of water flowing past a point per unit time, commonly expressed as 

cubic feet per second, million gallons per day, gallons per minute, or cubic meters per 

second. 

water diversion: Removing water from the natural course or location, or controlling water in its 

natural course or location, by means of a ditch, canal, flume, reservoir, bypass, pipeline, 

conduit, well, pump, or other structure or device. 

water table: The surface of underground, gravity-controlled water. The level of ground water. The 

boundary in the ground between where the ground is saturated with water and where the 

ground is filled with water and air. 

water management plan: A plan developed to help assure water quality compliance for both 

point and non-point pollution sources. 

watershed: The entire land area that contributes water to a particular drainage system or stream. 

water quality: The interaction between various parameters that determines the usability or nonusability of water for on-site and downstream uses. Major parameters that affect water 

quality include: temperature, turbidity, suspended sediment, conductivity, dissolved oxygen, 

pH, specific ions, discharge, and fecal coliform. 

WDOT: Wyoming Department of Transportation. 

weathering: The process whereby larger particles of soils and rock are reduced to finer particles 

by wind, water, temperature changes, and plant and bacteria action. 

well: A hole or shaft drilled into the earth to get water or other underground substances. A bored, 

drilled, or driven shaft, or dug hole, whose depth is greater than the largest surface 

dimension and whose purpose is to reach underground water supplies or oil, or to store or 

bury fluids below ground. 

well field: Area containing one or more wells that produces useable amounts of water, oil or gas. 

WET tests: Acute whole effluent toxicity (WET) tests. Laboratory tests where Fathead Minnows 

and Daphnia magna are placed in effluent water for up to 96 hours to determine 

survivability. 

8­30  Seminoe Road Gas Development Project
X 

November 2005 Draft Environmental Impact Statement

wetlands: Those areas that are inundated or saturated by surface or groundwater at a frequency 

and duration sufficient to support, and that under normal circumstances, do support a 

prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands 

generally include swamps, marshes, bogs, etc. (See “jurisdictional wetlands.”) 

WGFD: Wyoming Game and Fish Department. 

wilderness: Land designated by Congress as a component of the National Wilderness 

Preservation System. 

wind rose: A diagram showing the relative frequency of winds blowing from different directions. 

withdrawal: Water removed from the ground or diverted from the surface water source for use. 

The process of taking water from a source and conveying it to a place for a particular type 

of use. 

WNHP: Wyoming Natural Heritage Program. 

WOGCC: Wyoming Oil and Gas Conservation Commission. 

Y 

yield: The quantity of water that can be collected for a given use from surface or ground water 

sources. 

Z 

zone of saturation: A subsurface zone in which all the interstices are filled with water under 

pressure greater than that of the atmosphere. Although the zone may contain gas-filled 

interstices, it is still considered saturated.. 

zoning: Identification of areas of specified uses or restrictions. 

Seminoe Road Gas Development Project 8­31
November 2005 Draft Environmental Impact Statement

Chapter 9 – Index

Chapter 1

APD, 8 

BLM, 1, 2, 3, 4, 5, 6, 7, 8 

Carbon County, 1, 4, 5 

Hanna, 1, 3 

Hanna Basin, 1 

Issues, 3 

National Environmental Policy Act, 2 

Native American, 3 

NEPA, 2, 3, 6, 7, 8 

No Action Alternative, 7 

Noise, 4 

North Platte River, 3, 4 

Paleontology, 6 

Pilot Project, 1, 2 

Rawlins, 1, 2, 3 

Resource Management Plan, 7, 8 

RMP, 7, 8 

Scoping, 2, 3 

Seminoe Reservoir, 3, 4 

Seminoe Road, 1, 2, 3, 4, 6, 7, 8 

Seminoe State Park, 5 

U.S. Fish and Wildlife Service, 6 

USFWS, 6 

Visual Resource Management, 5 

VRM, 5 

WAPA, 5 

Weeds, 4 

Wildlife, 5 

Seminoe Road Gas Development Project 9­1
Draft Environmental Impact Statement November 2005

Chapter 2

Alternatives, 1, 2, 29, 30, 35, 39 

APD, 4, 17, 26 

Aquatic, 24 

BLM, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 14, 16, 17, 

18, 19, 21, 22, 24, 25, 26, 27, 28, 29, 30, 

31, 35, 40, 41, 45 

Bureau of Reclamation, 10 

Carbon County, 10, 12, 20, 21, 28, 32, 43, 

44, 46 

County Road 351, 11, 20, 27 

Directional drilling, 31 

Employment, 44 

Endangered, 26 

Environmental Protection Agency, 21 

EPA, 21 

Erosion, 3, 22, 41 

Evaporation, 35, 36, 39 

Fox Hills, 2, 3, 4, 14 

Grazing, 27 

Hanna, 8, 37 

Hanna Basin, 8 

Irrigation, 35 

Issues, 48 

Medicine Bow, 2, 3, 4, 14 

Mesaverde, 2, 3, 4, 14 

Miracle Mile, 43 

NEPA, 1, 2, 4, 17, 29, 32, 35 

No Action Alternative, 1 

Noise, 25, 42 

North Platte River, 6, 10, 12, 13, 14, 20, 27, 

33, 35, 40, 41, 43, 45, 48 

Pilot Project, 1, 3, 9, 14, 29, 31, 32, 33, 38, 

40, 41, 42, 43, 44, 45, 46, 47, 48 

Pool Table Draw, 9, 40, 41, 45 

Pronghorn, 47 

Raptor, 25, 26 

Rawlins, 9, 15, 21, 37, 44 

Reclamation, 6, 16, 19, 21, 23, 24, 27, 28, 

30 

Resource Management Plan, 18 

RMP, 4, 16, 35, 36 

Seminoe Reservoir, 2, 6, 10, 12, 13, 14, 20, 

27, 35, 36, 40, 41, 45, 46, 48 

Seminoe Road, 2, 3, 4, 7, 9, 10, 11, 12, 14, 

15, 16, 27, 28, 29, 30, 31, 32, 33, 34, 35, 

36, 37, 38, 40 

Seminoe State Park, 43, 46 

SHPO, 17, 18, 40 

Sinclair, 37 

State Historic Preservation Office, 17 

Underground injection, 14, 35 

USFWS, 17, 26 

VRM, 27 

WAPA, 11, 32, 34, 42 

Weeds, 19, 42 

Wetlands, 24 

WGFD, 17, 26 

Wildlife, 25, 26, 30, 45, 46 

WOGCC, 6, 24, 29, 31 

Wyoming Department of Environmental 

Quality, 9 

Wyoming Department of Transportation, 21 

Wyoming DEQ, 9, 11, 22, 23, 24, 25, 29, 38, 

40 

Wyoming Game and Fish Department, 17 

Wyoming Oil and Gas Conservation 

Commission, 6 

9­2 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Chapter 3

ADT, 83, 84 

Alkali Flat Spring #1, 36 

Aquatic, 16, 48, 58 

Ayers Draw, 22, 23, 25, 26, 35, 51, 52 

Black-footed ferret, 60, 63 

BLM, 4, 5, 7, 11, 13, 17, 18, 22, 32, 50, 51, 

52, 53, 56, 57, 59, 62, 63, 64, 65, 66, 67, 

68, 69, 70, 72, 82, 85, 86, 87, 88, 97 

Bureau of Reclamation, 18, 20, 83 

Carbon County, 2, 12, 50, 51, 52, 65, 70, 72, 

75, 84, 85, 88, 89, 90, 91, 92, 93, 94, 95, 

96, 97, 98, 100, 101, 102 

Climate, 1, 2 

Corral Creek Spring, 35 

County Road 351, 50, 83, 84, 85 

Cumulative impacts, 5 

Developed recreation, 83 

Dirtyman Draw, 22, 23, 25, 27 

Dry Ditch, 22, 23, 25, 27, 28, 38, 39, 51, 52 

Elk, 54, 84, 85 

Employment, 93, 94 

Endangered, 51, 52, 56, 57, 59, 60, 61, 63, 

67 

EPA, 3, 18, 71, 72 

Ephemeral drainage, 22 

Erosion, 23 

Forest Service, 5, 6 

Fox Hills, 12, 31, 33 

Geology, 11, 12, 30 

Grazing, 68, 69 

Hanna, 6, 12, 13, 15, 17, 30, 31, 33, 34, 68, 

84, 85, 88, 89, 90, 91, 92, 93, 94, 96, 98, 

102 

Hanna Basin, 6, 12, 15, 17, 30, 31, 32, 34 

Headcutting, 27 

Income, 94, 95, 99 

Interstate 80, 58, 84 

Kortes Reservoir, 14, 15, 18, 19 

Medicine Bow, 12, 13, 14, 15, 16, 18, 21, 31, 

33, 35, 36, 38, 39, 40, 54, 55, 63, 84, 85 

Mesaverde, 12, 31, 32, 33, 34, 35, 36, 37, 

38, 39 

Miller Bend Spring, 36 

Miracle Mile, 13, 15, 19, 20, 58, 82, 83, 84, 

85 

Mountain Lion Draw, 22, 23, 29, 51, 52 

Mountain plover, 60, 64 

Native American, 76, 78, 79 

NEPA, 79 

Noise, 70, 71, 72, 73 

North Platte River, 7, 14, 15, 17, 18, 19, 20, 

21, 25, 28, 29, 34, 41, 47, 48, 49, 52, 53, 

54, 55, 56, 57, 58, 59, 64, 65, 66, 67, 69, 

70, 80, 81, 82, 83, 84, 85, 86 

Paleontology, 13 

Pathfinder Reservoir, 13, 15, 19, 20, 58 

Pilot Project, 13, 25, 26, 30, 32, 47, 49, 50, 

53, 62, 63, 70, 72, 86 

Pool Table Draw, 22, 23, 24, 25, 26, 32, 47, 

49, 50, 51 

Precipitation, 1, 2 

Pronghorn, 53, 54, 55 

Range, 54, 71, 85 

Raptor, 56 

Rawlins, 1, 2, 7, 12, 14, 59, 65, 68, 84, 85, 

88, 89, 90, 91, 92, 93, 94, 96, 97, 98, 99, 

102 

Reclamation, 42 

Revenue, 100 

Riparian, 47, 48, 49 

RMP, 70, 88 

Sage-grouse, 56, 66 

Seminoe Reservoir, 7, 13, 14, 15, 16, 17, 18, 

19, 20, 21, 22, 24, 25, 26, 29, 34, 38, 42, 

47, 49, 50, 51, 52, 53, 54, 55, 56, 58, 59, 

63, 64, 66, 67, 68, 69, 72, 76, 80, 82, 83, 

85, 86, 90 

Seminoe Road, 6, 7, 13, 14, 22, 30, 31, 33, 

34, 37, 40, 53, 63, 70, 71, 72, 73, 74, 75, 

77, 78, 80, 82, 83, 84, 85, 87 

Seminoe State Park, 82, 83 

SHPO, 77 

Sinclair, 68, 82, 84, 85, 88, 89, 90, 91, 92, 

93, 94, 96, 99, 102 

Temperature, 1, 2 

U.S. Geological Survey, 5 

USFWS, 53, 57, 59, 63, 65, 66, 68 

USGS, 13, 17, 18, 19, 20, 21, 22, 32, 33 

Visual Resource Management, 86, 87, 88 

VRM, 87, 88 

WAPA, 70 

Weeds, 50, 51, 52 

Wetlands, 16, 47 

WGFD, 53, 54, 55, 56, 58, 59, 66 

Seminoe Road Gas Development Project 9­3
Draft Environmental Impact Statement November 2005

Wildlife, 53, 54, 66


Wyoming Department of Transportation, 84


Wyoming DEQ, 4, 6, 7, 15, 17, 18, 19, 20,


21, 22, 26


Wyoming Game and Fish Department, 18


9­4 Seminoe Road Gas Development Project
November 2005 Draft Environmental Impact Statement

Chapter 4

ADT, 92 

Air quality, 2, 3 

Alkali Flat Spring #1, 46, 49 

Alternatives, 3, 10, 11, 12, 17, 20, 21, 25, 

43, 44, 46, 47, 48, 50, 53, 54, 60, 64, 77, 

78, 80, 82, 83, 84, 86, 87, 88, 90, 92, 93, 

98, 100, 102, 104, 114 

APD, 70, 76, 83, 87 

Aquatic, 62 

Ayers Draw, 27, 29 

BLM, 2, 3, 8, 9, 11, 14, 17, 21, 22, 23, 25, 

28, 29, 33, 38, 41, 43, 44, 52, 57, 60, 62, 

63, 64, 66, 70, 71, 72, 73, 74, 75, 77, 80, 

81, 82, 83, 87, 88, 89, 90, 91, 93, 99, 101, 

113, 114, 116 

Bureau of Reclamation, 35, 92, 102 

Carbon County, 54, 67, 80, 82, 85, 89, 90, 

91, 93, 94, 95, 96, 97, 98, 99, 100, 101, 

102, 103, 104, 105, 106, 107, 108, 109, 

110, 111, 112, 113, 114, 115 

Climate, 1 

Corral Creek Spring, 46, 49 

County Road 351, 67, 85, 86, 90, 93, 94, 95, 

96, 97, 98, 99, 100, 101, 118 

Cultural resources, 86 

Cumulative impacts, 7, 92, 103 

Dirtyman Draw, 27, 29, 33 

Dry Ditch, 27, 29, 47, 50 

Elk, 101 

Emissions, 4, 6, 10 

Employment, 104, 105, 106, 107, 108, 110 

Endangered, 57, 62, 63, 74, 76 

EPA, 2, 3, 4, 7, 10, 23 

Ephemeral drainage, 28 

Erosion, 12, 13, 16, 25, 28, 29, 31 

Forest Service, 2, 8, 9 

Fox Hills, 20, 21, 41, 42, 45, 49, 51 

Geology, 20 

Grazing, 61, 81 

Hanna, 21, 38, 41, 50, 71 

Hanna Basin, 21, 41, 50, 71 

Income, 104, 105, 106, 110, 111 

Interstate 80, 95, 96 

Irrigation, 38 

Kortes Reservoir, 35 

Land use, 79 

Medicine Bow, 20, 21, 38, 41, 42, 43, 44, 45, 

46, 47, 49, 50, 51, 77 

Mesaverde, 20, 21, 41, 42, 43, 44, 45, 46, 

47, 48, 49, 50, 77 

Miller Bend Spring, 46, 49 

Miracle Mile, 3, 22, 23, 24, 35, 37, 39, 72, 

73, 90, 91, 92, 99 

Mountain Lion Draw, 28, 29 

Mountain plover, 74 

Native American, 86, 88, 89 

NEPA, 39, 87, 88 

No Action Alternative, 45 

Noise, 83, 84, 85, 86, 91 

North Platte River, 11, 17, 22, 23, 24, 27, 33, 

34, 35, 36, 37, 38, 39, 40, 41, 44, 45, 47, 

48, 51, 60, 71, 72, 73, 74, 76, 77, 78, 91, 

95, 97, 99, 117 

Pathfinder Reservoir, 36 

Pilot Project, 3, 12, 20, 23, 24, 25, 28, 29, 

30, 36, 41, 42, 43, 44, 45, 53, 54, 57, 63, 

68, 76, 78, 80, 82, 84, 87, 93, 100, 104 

Pool Table Draw, 17, 23, 24, 25, 27, 28, 29, 

30, 37, 42, 43, 45, 53, 58, 78, 82 

Range, 92 

Raptor, 71 

Rawlins, 7, 86, 88, 91, 95, 96, 102, 103, 105, 

107, 108, 109, 114, 115, 116 

Reclamation, 26, 35, 52, 53, 54, 58, 62, 79, 

82, 99, 105, 106, 118 

Resource Management Plan, 87 

Revenue, 111 

Riparian, 29, 42, 52, 53, 56 

RMP, 52, 98 

Sage-grouse, 64, 75 

Sediment control, 26 

Seminoe Reservoir, 3, 11, 17, 18, 22, 23, 24, 

25, 26, 27, 28, 33, 34, 35, 36, 37, 38, 39, 

40, 47, 53, 60, 71, 72, 78, 81, 90, 91, 92, 

95, 99, 101, 101, 102 

Seminoe Road, 2, 6, 7, 9, 11, 17, 19, 20, 21, 

22, 23, 28, 31, 36, 38, 39, 40, 41, 44, 45, 

46, 48, 50, 51, 54, 61, 63, 68, 69, 70, 73, 

74, 76, 77, 80, 82, 84, 85, 86, 87, 88, 89, 

91, 92, 95, 96, 98, 101, 103, 104, 105, 

106, 107, 108, 109, 110, 111, 112, 113, 

114, 115, 116 

Seminoe State Park, 90, 91, 92 

Sinclair, 7, 91, 95 

Seminoe Road Gas Development Project 9­5
Draft Environmental Impact Statement November 2005

Underground injection, 21 

USFWS, 62, 63, 64, 68, 72, 77 

USGS, 34, 35, 39 

Visual Resource Management, 91, 99 

VRM, 91, 98, 99, 101 

WAPA, 95, 100, 102, 116 

Weeds, 52, 56, 62 

Wetlands, 52, 62 

WGFD, 64, 68, 69, 70, 71, 75 

Wildlife, 62, 65, 67, 68, 69, 71, 74, 75, 77, 

79, 85 

WOGCC, 21 

Wyoming Department of Transportation, 96 

Wyoming DEQ, 2, 3 

Wyoming Game and Fish Department, 62 

9­6 Seminoe Road Gas Development Project
APPENDICES
Appendix A 

Proponent’s Project Description 
November 2005 Draft Environmental Impact Statement

Appendix A – Proponent’s Project Description

PREFACE 

This document is the product of several years of geological exploration, reservoir engineering 

evaluation, economic feasibility studies, environmental investigations, as well as the preliminary 

results from the pilot project operations conducted by Dudley & Associates, LLC (Dudley) in 

Carbon County, Wyoming. 

The planning process has sought to consistently balance the application of these professional 

disciplines. By working closely with a combination of government agencies and independent 

technical experts, Dudley believes this plan represents the best overall approach to coalbed 

natural gas development in the Hanna Basin. 

This project description provides key background information for the National Environmental 

Policy Act (NEPA) work initiated by the Bureau of Land Management (BLM) for the Seminoe 

Road Gas Development (Seminoe Road) Project and includes discussion on the following items: 

3⁄4 General project description; 

3⁄4 Existing related projects; 

3⁄4 Pre-construction planning and site layout; 

3⁄4 Construction and drilling operations; 

3⁄4 Production and maintenance activities; 

3⁄4 Miscellaneous related operations; 

3⁄4 Reclamation and decommissioning; 

3⁄4 Water management; 

3⁄4 Power; 

3⁄4 Workforce; 

3⁄4 Transportation and traffic; and, 

3⁄4 Environmental mitigation and management measures. 

Seminoe Road Gas Development Project A-i 
Draft Environmental Impact Statement November 2005

Dudley notes that the design and planning of coalbed natural gas development is an evolving 

science. This project description represents the proponent’s current proposal; however, 

modifications often result from the feasibility studies and design engineering processes. Any such 

material changes will, of course, be reflected in the forthcoming draft environmental impact 

statement (EIS), the permitting processes, as well as the final design for the approved plan of 

development. 

A-ii Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

LIST OF ACRONYMS AND ABBREVIATIONS 


APD Application for Permit to Drill or Reenter 

BLM Bureau of Land Management 

CBL Cement Bond Log 

CFR Code of Federal Regulations 

CIG Colorado Interstate Gas Company 

Dudley Dudley & Associates, LLC 

EA Environmental Assessment 

EIS Environmental Impact Statement 

EPA Environmental Protection Agency 

NAAQG National Ambient Air Quality Standards 

NEPA National Environmental Policy Act 

NOS Notice of Staking 

NPDES National Pollutant Discharge Elimination System 

PM Principal Meridian 

RMP Resource Management Plan 

ROW Right-of-Way 

SAR Sodium Adsorption Ratio 

SHPO State Historic Preservation Office 

SPCC Spill Prevention, Control and Countermeasure 

TDS Total Dissolved Solids 

USFWS United States Fish & Wildlife Service 

WAAQS Wyoming Ambient Air Quality Standards 

WDEQ Wyoming Department of Environmental Quality 

WGFD Wyoming Game and Fish Department 

WOGCC Wyoming Oil and Gas Conservation Commission 

Seminoe Road Gas Development Project A-iii 
November 2005 Draft Environmental Impact Statement

Contents

1.0 GENERAL PROJECT DESCRIPTION (SUMMARY OF THE PROPOSED ACTION) ... A-1

2.0 ANCILLARY PROJECTS.................................................................................... A-5

2.1 Pilot Project.............................................................................................. A-6

2.2 Interconnect Pipeline and Compressor Facility....................................... A-6

2.3 Water Handling and Treatment Facilities................................................ A-7

3.0 PRE-CONSTRUCTION PLANNING AND SITE LAYOUT ....................................... A-7

4.0 CONSTRUCTION ACTIVITIES ........................................................................... A-8

4.1 Roads and Well Pads................................................................................. A-8

4.1.1 Road Construction........................................................................................A-8

4.1.2 Well Pad Construction..................................................................................A-9

4.2 Construction Staging and Laydown Areas............................................. A-10

5.0 DRILLING OPERATIONS ................................................................................ A-10

5.1 General Description................................................................................ A-10

5.2 Completion and Testing Operations ...................................................... A-12

5.3 Drilling Water ......................................................................................... A-12

6.0 PRODUCTION OPERATIONS .......................................................................... A-13

6.1 Well Pads (including wellsites)............................................................... A-13

6.2 Gas and Water Gathering Systems......................................................... A-14

6.2.1 Gas Lines .....................................................................................................A-14

6.2.2 Water Lines.................................................................................................A-14

6.3 Compressor Stations .............................................................................. A-14

6.4 Pipeline Delivery and Terminal Facilities............................................... A-16

7.0 MAINTENANCE ACTIVITIES .......................................................................... A-16

7.1 Roads ...................................................................................................... A-16

7.2 Compressor Stations .............................................................................. A-16

7.3 Water Treatment Facilities .................................................................... A-16

7.4 Natural Gas Production Wells ................................................................ A-17

7.4.1 Operations ..................................................................................................A-17

7.4.2 Well Site Work-Overs..................................................................................A-17

8.0 RECLAMATION ............................................................................................. A-17

8.1 Interim Reclamation............................................................................... A-18

8.1.1 Soil Removal and Stockpiling......................................................................A-19

8.1.2 Interim Stabilization and Revegetation......................................................A-19

8.1.3 Well Site and Road Reclamation.................................................................A-19

8.2 Final Closure and Reclamation............................................................... A-19

8.2.1 Facilities Decommissioning ........................................................................A-20

8.2.2 Structures, Facilities and Roads Removal ..................................................A-20

8.2.3 Well Abandonment and Sealing .................................................................A-20

8.2.4 Recontouring and Regrading .....................................................................A-20

8.2.5 Soil Replacement and Mulching .................................................................A-20

8.2.6 Permanent Revegetation...........................................................................A-21

8.2.7 Reclamation Management and Monitoring................................................A-21

9.0 WATER MANAGEMENT................................................................................. A-21

9.1 Water Use ............................................................................................... A-22

Seminoe Road Gas Development Project A-i 
Draft Environmental Impact Statement November 2005

9.2 Dewatering Operations .......................................................................... A-22

9.3 Water Treatment and Discharge............................................................ A-23

10.0 POWER ........................................................................................................ A-25

11.0 WORK FORCE ............................................................................................... A-26

12.0 TRANSPORTATION/TRAFFIC ........................................................................ A-26

13.0 APPLICANT-COMMITTED MITIGATION AND MANAGEMENT MEASURES FOR

ENVIRONMENTAL PROTECTION ................................................................... A-27

13.1 Pre-construction Planning and Design .................................................. A-28

13.2 Sewage, Trash and Other Waste Material.............................................. A-29

13.3 Cultural and Historic Resources............................................................. A-29

13.4 Paleontological Resources...................................................................... A-30

13.5 Vegetation .............................................................................................. A-30

13.6 Noxious Weeds........................................................................................ A-30

13.7 Road Construction/Transportation ....................................................... A-31

13.8 Chemicals and Hazardous Materials....................................................... A-32

13.9 Air Quality............................................................................................... A-33

13.10 Topography and Physiography............................................................... A-33

13.11 Soils......................................................................................................... A-33

13.12 Water Resources..................................................................................... A-34

13.13 Wetlands, Other Special Aquatic Sites, Other Waters of the U.S.......... A-35

13.14 Noise and Odor ....................................................................................... A-35

13.15 Wildlife and Fisheries ............................................................................. A-35

13.16 Threatened, Endangered, Proposed, Candidate and Sensitive Species A-36

13.17 Livestock/Grazing Management............................................................. A-36

13.18 Socioeconomics ...................................................................................... A-36

13.19 Land Status Use/Access.......................................................................... A-36

13.20 Recreation .............................................................................................. A-36

13.21 Visual Resources ..................................................................................... A-36

13.22 Health and Safety................................................................................... A-37

Tables 

Table A-1, Preliminary Estimate of Surface Area Disturbance ....................................................A-2


A-ii Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

1.0 GENERAL PROJECT DESCRIPTION (SUMMARY OF THE PROPOSED 

ACTION) 

Dudley submits this project description to the BLM in preparation for the development and 

operation of a full-scale coalbed natural gas project identified as the Seminoe Road Gas 

Development (Seminoe Road) Project. 

The Seminoe Road Project is situated in Townships 21, 22, 23 and 24 North, Ranges 84, 85 and 

86 West, 6th Principal Meridian (PM), which lie in the northwest Hanna Basin, Carbon County, 

Wyoming. The project area is located approximately 20 miles northeast of the City of Rawlins, 18 

miles north-northeast of the Town of Sinclair, and generally east of Carbon County Road 351 

(Seminoe Road). See Figure 1, General Location Map. 

Dudley is the project proponent and has identified potential well sites for as many as 1,240 

coalbed natural gas wells on 785 drill pad locations. See Table A-1, Preliminary Estimate of 

Surface Area Disturbance. 

The project area is approximately 137,600 acres (215 sections) in size and embraces a 

checkerboard ownership pattern of federal (>49%) and private (fee) (>49%), with some state 

surface. The BLM Rawlins Field Office manages the federal surface and mineral estates. 

Dudley owns or controls oil and gas leasehold interests comprising approximately 83% of the 

project area. The BLM manages the balance of the leased and un-leased federal oil and gas 

interests in the project area. 

Two discrete Cretaceous coal formations are found in the potential development area, each 

separated by several thousand feet of low permeability sand and shale--the deeper Mesaverde 

coals (more specifically, the Almond and Allen Ridge members) and the shallower Medicine Bow 

and Fox Hills coals (regional equivalents of the Lance formation). For the purposes of this 

document, the Mesaverde members may be commercially productive of coalbed natural gas at 

depths ranging from 500’ to 14,000’. Similarly, the overlying Medicine Bow and Fox Hills 

formations may produce commercial quantities of coalbed natural gas from 500' to 10,000' 

depths. 

Seminoe Road Gas Development Project A-1 
Draft Environmental Impact Statement November 2005

1 Table A-1, Preliminary Estimate of Surface Area Disturbance

Facility 

Initial Disturbance Area2 

(acres) 

Area of Operations3 

(acres) 

Drill Pads 4 1,727 785 

Access Roads5 2,854 1,427 

Utilities6 1,427 0 

Water Discharge Facilities7 79 79 

Compressor Facilities8 30 30 

Total Disturbed Area 6,117 2,321 

Percentage Disturbance of Total Project Area9 4.5% 1.7% 

Notes: 

(1) This table presents the total area estimated by the Proponent to be disturbed within the Seminoe Road Gas 

Development Project during the projected 30-year life of the project. 

(2) The initial disturbance represents the area disturbed as a result of drill pad construction, access roads, gas, 

water and utility rights-of-way, compressor stations, and treated water-handling systems. 

(3) Part of the area initially disturbed by drilling operations would be reclaimed (~55%) shortly after each well is 

completed and equipped. The area not reclaimed would be used for ongoing operations. Once the gas 

resource is depleted, facilities would be removed and the balance of the drill pad would then be reclaimed. 

(4) An estimated 785 drill pads would be created in the project area. The initial drill pad surface disturbance (i.e., 

the area needed for drilling operations) will average 2.2 acres apiece. Subsequent reclamation would reduce 

the drill pad size to approximately one (1) acre, the area needed for production operations. 

(5) Each drill pad will require an estimated 0.6 miles of access road for which an estimated width of 50’ will be 

physically affected by the construction process. Fifty percent (50%) of the area initially disturbed by road 

construction (25%) will be reclaimed following construction activities. Access roads would remain in service 

for the life of the project. 

(6) “Utilities” include gas and water collection pipelines, power lines and their ancillary facilities, and 

communications lines. Utilities corridors are ordinarily laid out parallel to and installed simultaneously with 

the access roads, initially utilizing an average width of 25’ and an average 0.6 miles length for each drill pad. 

Once utilities are installed and buried, the disturbed areas will be fully reclaimed. 

(7) The measured surface disturbance at the Seminoe Road CBM Pilot Project for DS-1, DS-2 and DS-3 water 

treatment facilities is 1.26 acres serving 16 wells. Experience indicates that the construction, installation, and 

operation of water discharge facilities will entail a disturbance of 0.1 acres allocated to each drill pad. These 

facilities would remain in service for the life of the project. 

(8) It is also presumed that three (3) compressor stations will be required to adequately serve the project, each 

requiring an estimated ten (10) acres, for a total projected disturbance of 30 acres. 

(9) This percentage is based on a measured 137,000 acres within the EIS analysis. 

The apparent duplication of producing horizons is due to the locally steep dip of the sedimentary 

section, which plunges east, into the basin, at 10° to 15° within the area of interest. Both sets of 

coals outcrop (i.e. intersect the surface) at different points along the western edge of the Hanna 

Basin and rapidly dip to over 30,000' only 25 miles east of that outcrop. The Hanna Basin is 

geologically unique in the Rocky Mountain oil and gas provinces in that it is both the smallest and 

the deepest such basin; it is only 50 miles across at its widest point but carries a stratigraphic 

interval 7~ miles deep. 

The Cretaceous coals of the western Hanna Basin are well-cleated (i.e. fractured), highly 

permeable, freshwater aquifers. Methane, commonly called natural gas, is the simplest of all 

hydrocarbon molecules (CH4); it is physically bound to the coal by positive-negative ion attraction. 

The accepted theory is that methane is adsorbed onto the internal surface of the coal in a 

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November 2005 Draft Environmental Impact Statement

monolayer—a single layer of methane molecules stuck to the surface with no stacking. When the 

coal is fully saturated with methane molecules, the monolayer approaches what could be called a 

liquid, but it never reaches the solid phase. 

Methane molecules are held in place by the hydrostatic head—the pressure exerted by the height 

of a column of water at a given depth. Freshwater has a hydrostatic gradient of 0.433 psi/ft; 

accordingly, the formation pressure at 6,000' is 2,598 psig (6,000' x 0.433 = 2,598). 

Coalbed reservoir temperature and pressure determine how much methane can be held in place 

(i.e. equilibrium). As the reservoir pressure is drawn down, the methane will try to equalize as 

CH4 molecules in the matrix react to lower pressure in the cleats; eventually, the pressure 

differential grows large enough to break the physical bond, and the gas molecule peels off into 

the micropores inside the coal matrix. Gradually it diffuses through the coal micropore network 

and works its way toward the cleat. It enters the cleat as a gas, and since water in the cleat is 

already saturated with gas, it cannot accept any more methane into solution. These new methane 

molecules entering the system of coal cleats build gas saturation levels, which, in turn, increase 

the relative permeability of gas to the wellbore, and provide the inclining production trend. 

In this hydraulically closed system, everything is at equilibrium, and pressure depletion can only 

occur by artificial means, ordinarily by drilling and casing a well and setting a pump to bring 

formation water to the surface. The rated pump capacity must exceed the rate of fluid entry from 

the coalbed for hydrostatic pressure to drop and lower the fluid level in the wellbore. The more 

the reservoir pressure drops, a “pressure sink” is created around each wellbore. As the radius of 

this “sink” enlarges, the formation pressures between multiple wellbores will interfere with each 

other, increasing the rate of depletion and hence, the rate of gas desorption. 

Accordingly, it is critical that the pilot project yields sufficient data to develop models of the 

physical behavior of these several coal formations at different hydrostatic pressures. By 

determining the theoretical maximum gas storage capacity at a given pressure and temperature, 

a series of data points can be extrapolated called the “adsorption isotherm.” From that point, it’s 

possible to infer whether the coal is gas-saturated and how much pressure depletion must occur 

before coalbed gas will begin to desorb. 

Simply put, the goal is to produce enough water, quickly enough, to lower the ambient formation 

pressure to the point where it intersects the isotherm curve. 

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Draft Environmental Impact Statement November 2005

Pressure versus depth plot


Dudley plans to request 160-acre drilling and spacing units across the project area. The shallower 

Medicine Bow and Fox Hills coalbed formations will be produced from separate, “twin” wellbores, 

so-called because they share a common drill pad with their Mesaverde counterparts to minimize 

the surface area disturbed by the development of both formations. 

Field development will require construction of access roads, drill pads, gas gathering and water 

collection lines, electric utilities, water treatment and discharge facilities, equipment storage yards 

and compressor stations. It is estimated that 55% of the originally disturbed surface will be 

reclaimed as soon as is practicable following drilling, completing, testing and equipping 

operations. The aerial extent of surface disturbance for the Seminoe Road Project is estimated in 

Table A-1, Preliminary Estimate of Surface Area Disturbance. 

The initial analysis of natural gas taken from Pilot Project (well UPLRC 4-35-24-85) producing 

from the Mesaverde coals indicates the presence of “pipeline quality” gas. Consequently, there 

appears to be no present need for nitrogen or CO2 extraction facilities. An EA for a compressor 

facility, storage yard and a 20.3-mile high-pressure gathering pipeline was approved in 2002 to 

enable future delivery of produced gas to markets at interconnections near Walcott, Wyoming. 

Construction of these facilities, however, will await further production testing of the pilot project to 

confirm that coalbed natural gas can, in fact, be produced in paying quantities. 

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November 2005 Draft Environmental Impact Statement

The surface discharge of water produced from coalbed natural gas wells is regulated under a 

National Pollutant Discharge Elimination System (NPDES) permit issued by the Wyoming 

Department of Environmental Quality (WDEQ). Dudley currently monitors and discharges treated 

water from pilot project wells under NPDES Permit WYW 004-1807. 

Applications for Permits to Appropriate Ground Water (Form U.W. 5) have been issued by the 

Office of the State Engineer for each of the pilot project wells. As and when additional wells may 

be drilled, similar ground water appropriation permits will be sought by application to the State 

Engineer. 

Produced water pipelines will be constructed, as necessary, from well pad sites to water 

treatment and discharge facilities. Produced water quality will continue to be monitored in 

accordance with state and federal regulations. 

Primary field development of the Mesaverde coals is anticipated to occur over the course of 6 to 8 

years, with secondary, shallower objectives in the Medicine Bow and Fox Hills formations 

requiring an additional 3 to 4 years. Dudley plans to initiate field development in 2005 following 

satisfaction of NEPA requirements and receipt of certain federal, state, and local regulatory 

approvals. 

The overall period of drilling, operating, and reservoir production to its economic limit, as well as 

the decommission and final reclamation stages of the project, can be estimated to last thirty (30) 

years, or more, if field development reaches the potential limits described herein. 

In addition to the usual and customary federal, state and local regulatory requirements, the 

factors that will control the rate of field development and production operations include, but are 

not limited to: a.) the diminishing availability of qualified drilling contractors and, more particularly, 

equally qualified personnel to operate those rigs; b.) third-party services essential to drilling, 

logging, completing, testing and equipping processes; c.) oil and gas lease acquisitions, expiries, 

and attendant stipulations limiting the period for surface access; d.) contractual obligations; e.) 

weather; and, f.) access to capital and gas markets, and g.) fluctuating commodity prices. 

2.0 ANCILLARY PROJECTS 

The Seminoe Road Project has been preceded by the following activities: 

Seminoe Road Gas Development Project A-5 
Draft Environmental Impact Statement November 2005

3⁄4 Pilot Project; 

3⁄4 Gas Gathering Pipeline and Compressor Facility EA; and, 

3⁄4 Pilot Project Water Handling and Treatment Facilities. 

2.1 Pilot Project 

The pilot project consists of 16 wells drilled, completed and produced to evaluate whether the 

objective formations have suitable reservoir characteristics for commercial development of 

coalbed natural gas. Two additional wells have been approved, but those locations have not yet 

been developed. The pilot project wells are drilled and spaced on 160-acre units; in each case 

the plug-back total depth (PBTD) penetrates through the Allen Ridge member of the Mesaverde 

formation (6,000'). 

The pilot project wells and associated roads lie in Townships 23 and 24 North, Range 85 West, 

6th PM, Carbon County, Wyoming. See Figure 4, General Layout Map. 

Details of the pilot project are discussed in the Environmental Assessment (EA) for the Seminoe 

Road Coalbed Methane Pilot Project (WY-030-EA00-288). 

2.2 Interconnect Pipeline and Compressor Facility 

Dudley received approval from the BLM in 2002 for the construction of a natural gas compressor 

facility and a 20.3-mile, 16'' diameter, high-pressure gathering pipeline to move gas from the pilot 

project to markets located at a set of commercial interconnects near Walcott, Wyoming. The 

pipeline rights-of-way and associated facilities are shown on Figure 4, General Layout Map. 

The design calls for relatively low-pressure wellhead gas from the pilot project wells to flow 

through an infield gathering system to the inlet of a centrally located dehydration and compressor 

site. From the compressor outlet, gas will be delivered to the Walcott interconnects in the highpressure gathering pipeline. Detailed specifications for construction and development are set 

forth in the EA for the Seminoe Road Coalbed Methane Natural Gas Gathering Pipeline/Access 

Road and Compressor Station/Storage Yard/Access Road Project (WY-030-EA2-229). 

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November 2005 Draft Environmental Impact Statement

2.3 Water Handling and Treatment Facilities 

The water produced during pilot project operations has been collected through underground 

water gathering lines to two separate but identical treatment facilities (DS-2 and DS-3). Produced 

water is initially sprayed through nozzles into horizontal 400 bbl aeration tanks. The nozzles, 

resembling modified shower heads, are designed to mix air and produced water, which causes 

iron dissolved in the water to oxidize; that is, they turn to rust particles which tend to drop out of 

solution. 

The aerated water flows by gravity to specially constructed fiberglass containers filled with both 

sand and gravel, a process that effectively “polishes” the aerated water by filtering total iron and 

manganese. See Figure 11, Water Treatment Facilities Layout. 

As was mentioned in Section 1.0, General Project Description, Dudley has obtained an NPDES 

permit from the WDEQ specifying three (3) approved discharge points. Samples of water 

discharged from the pilot project are regularly collected, analyzed, and have consistently met 

water quality standards set by the NPDES permit. 

3.0 PRE-CONSTRUCTION PLANNING AND SITE LAYOUT 

Prior to the start of construction activities for each individual project phase, Dudley will submit 

site-specific APD plans for the drilling, testing, completing and equipping process, including, but 

not limited to location surveys showing the area to be disturbed for access roads, drill pads, 

topsoil piles, pits, drilling and all related downhole procedures (including safety plans) and any 

other information the operator or the BLM deems relevant to the process. Each individual project 

phase will include a group of wells. 

The proposed development sites will be staked in the field and inspected by the BLM to ensure 

consistency with the application and that environmental resources are evaluated in such a way 

that proposed operations comply with the Great Divide Resource Management Plan (RMP) and 

any site-specific EIS decisions made for the Seminoe Road Project. 

Two procedural options are available to the operator for securing approval to drill: a.) a Notice of 

Staking (NOS); and, b.) an Application for Permit to Drill or Reenter (APD). Although timeframes 

set forth in the regulations are the same for both options, they do contain individual advantages. 

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Draft Environmental Impact Statement November 2005

The NOS system, properly coordinated at the beginning of the action, may expedite final permit 

approval; however, the APD system is the most familiar to oil and gas operators and often 

requires less coordination effort at the start. The choice of which option to use is the decision of 

the operator. 

Access roads and pipelines located on federal surface outside the leasehold or the unitized area 

require a right-of-way (ROW) for BLM lands. The NOS or APD for BLM land will be accepted as a 

ROW application for these off-lease facilities and the application should, therefore, detail the 

entire development proposal. At the NOS or APD onsite inspection, the operator will be provided 

the Form 2800-14 (ROW/Temporary Use Permit) containing standard terms and conditions, and 

Form 1323-2 (ROW cost recovery and fee determination record) for any ROWs involved on BLM 

land. Complete APDs involving a BLM ROW should include a signed form 2800-14 and any 

required ROW cost recovery fees. APD conditions of approval will also apply to ROW portions of 

the permit. 

The applications will be revised as necessary per negotiations with the BLM. The BLM may 

approve or deny site-specific proposals and any such conditions of approval will be attached to 

and become a part of each permit. Upon receipt of final BLM approval, the operator could 

commence with proposed activities. 

4.0 CONSTRUCTION ACTIVITIES 

4.1 Roads and Well Pads 

Construction activities on federal lands will follow procedures approved by the BLM each APD 

and any attached Conditions of Approval. 

The operator will save and separately retain topsoil bladed from any excavation activity for the 

eventual revegetation of the location. Topsoil stockpiles, if any, will be segregated from subsoils, 

stockpiled, and stabilized until used for reclamation. 

4.1.1 Road Construction 

Dudley will obtain proper authorizations for access roads. When the proposed project requires 

roads to be built on or across federal and private surface, they will be constructed following 

guidelines specified in the BLM Road Standards Manual, Section 9113. 

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November 2005 Draft Environmental Impact Statement

The plan for a typical road cross-section with parallel gas and water gathering lines is illustrated 

as Figure 7, Typical Access Road. 

Exact locations of project access roads within the project area are not finalized, however, as 

noted above, these locations will become a part of APD and ROW applications to the BLM prior 

to any actual construction. Newly constructed roads will be situated for minimal surface 

disturbance and will avoid sensitive resources (e.g., raptor nests, cultural resource sites, etc.), 

and maximize transportation efficiency. Roads will be built and maintained to provide year-round 

access. 

Surface disturbance for access roads will be contained within a requested 50-foot ROW. Actual 

disturbance created by road construction will vary with the topography. Wherever possible, 

existing roads will be upgraded to provide access to well sites; however, it is certain that new 

roads will need to be constructed. 

Access roads within the project area will serve well sites and support facilities. Maintenance 

practices will include road surface grading and maintaining drainage. Roads will be surfaced with 

rock aggregate (gravel) to accommodate year-round use, to allow the transport of heavy loads, 

and to minimize dust generation. 

Access roads will be reclaimed when the road is no longer needed. However, to satisfy possible 

requests by the BLM or the fee surface owner, an access road may be stabilized and allowed to 

revert to a two-track trail upon completion of the proposed project and/or need for the road. 

4.1.2 Well Pad Construction 

A typical drill pad will require approximately 2.2 acres for drilling operations. Each drill pad will 

include a level area for placement of the drilling rig and its ancillary equipment, as well as space 

for an earthen reserve pit, lined with impermeable fabric that will adequately contain drilling fluids 

and cuttings. See Figure 8, Typical Well Pad Layout During Drilling Activities. 

Topsoil will be separately stockpiled for future use in reclamation. Drill pads will be leveled and/or 

contoured using standard surveys, construction techniques and machinery. 

As previously addressed in Section 1.0, General Project Description, it is estimated that 785 drill 

pads would be constructed in the project area to adequately recover coalbed natural gas from the 

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Draft Environmental Impact Statement November 2005

Mesaverde coals. Dudley further surmises that 455 of these drill pads are also prospective for 

recovery of coalbed natural gas from the Medicine Bow and Fox Hills coals from a second well 

bore. After drilling activities and wellhead installations are completed the well pad site would be 

reclaimed, reducing disturbance from 2.2 acres to 1 acre. 

Well pads will be constructed over time as graphically illustrated on Figure 4, General Layout 

Map. 

4.2 Construction Staging and Laydown Areas 

The proposed project will eventually require three compressor sites, which also serve as staging 

locations for construction. Such activity may include, but is not limited to pipe racks, pipeline 

storage, equipment security, dispatch and maintenance. See Section 6.3, Compressor Stations 

and Figure 5, Projected Build-out Scenario (Mesaverde Formation). Truck transport will be 

used for moving equipment and supplies to and from the Seminoe Road Project. The 

compressor sites will double as equipment laydown and storage areas throughout the life of the 

project. 

5.0 DRILLING OPERATIONS 

5.1 General Description 

Once access road and drill pad construction are completed, rotary rig components will be 

transported by trucks to the drill pad and assembled on site. This is ordinarily a 10 to 12 hour 

process, depending upon the size and nature of the rig. See Figure 8, Typical Well Pad Layout 

During Drilling Activities. 

Cuttings and drilling fluids will be contained in the reserve pit, and drilling fluids will be recovered 

and reused as practical. The reserve pit will be lined, as specified in the APDs, to prevent loss of 

drilling fluids through seepage. If necessary, the reserve pit will first receive a sufficient layer of 

bedding material (e.g., sand) to prevent contact between the liner and any exposed rock. The 

reserve pit will be fenced to protect livestock and wildlife until the pit is backfilled and reclaimed. 

In the unlikely event that undesirable materials (e.g., hydrocarbon liquids) are [reserve pits are 

designed and intended to receive oil and condensate which is often produced while drilling 

petroliferous formations] discharged into a reserve pit, the materials will be carefully separated, 

A-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

removed and discarded in accordance with WDEQ and WOGCC requirements. If oil is observed 

in the pit and if it is not possible or practical to immediately remove such oil, the pit will be 

covered by a net to prevent waterfowl use. 

In the event that oil, gas or other noxious fluids are spilled during drilling, completing, testing or 

equipping operations, the operator will contact the BLM and such other regulatory agencies as 

are deemed necessary (or indicated in the APD) and will initiate clean-up procedures. Every 

reasonable effort will be made to confine equipment and vehicles to access roads, well pads, and 

ancillary facility areas specified in the approved APD. Dudley will prepare a spill prevention 

control & countermeasure plan and a Hazardous Materials Management Plan, which, will outline 

spill prevention and clean-up procedures. 

No abnormal temperatures, pressures or hydrogen sulfide gas is likely to be encountered during 

drilling. Freshwater aquifers and minable coals will be adequately protected in accordance with 

good oilfield practice and WOGCC requirements. This common practice ordinarily entails setting 

and cementing adequate steel casing across the appropriate intervals to isolate the formation in 

question and eliminate the possibility of fluid or pressure communication between zones. 

The quality of a primary cement job is evaluated by running a wire line acoustical geophysical log 

(cement bond log or CBL) through production casing after the cement has set. A favorable 

acoustic coupling occurs if there is adequate cement to fill the annular space between casing and 

wellbore. The resulting log signature evidences the degree of bonding across the cemented 

intervals. Dudley will use sufficient cement and make every reasonable effort to obtain full return 

of cement to the surface; however, a full return cannot always be obtained. For this reason, 

cement bond logs will be run in all wells completed for production. 

If a partial or incomplete cement bond can be identified within 100' above or below a production 

zone, the casing will be perforated at the appropriate interval, and additional cement pumped into 

the casing-wellbore annulus, and a second CBL will be run to determine the effectiveness of the 

additional cementing. The procedure will be repeated as necessary to ensure an adequate 

cement bond. 

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Draft Environmental Impact Statement November 2005

5.2 Completion and Testing Operations 

Production wells will be tested once casing and cementing activities are completed. Potentially 

productive coal seams will be perforated and tested to determine the ability of each to produce 

methane at commercially acceptable rates. Mesaverde, Medicine Bow, and Fox Hill coals 

typically average 2 to 12 feet in individual thickness. The interval between the coals in the 

Medicine Bow and Fox Hill formations averages between 40 and 70 feet. 

During well production testing, the rig used to drill the well will be replaced with a smaller surface 

rig that operates primarily during daylight hours. Well testing will occur by perforating the steel 

casing across potentially productive zones. Smaller tubing will then be placed in the cased hole 

and pumping equipment is set below the perforated intervals. 

Water will be pumped from the completed zone using progressive cavity or submersible pumps 

(see Section 6.0, Production Operations) until methane flow is established. This process may 

require 90 days or more of pumping to initiate diagnostic gas flow rates. 

Gas flows will be measured at the surface, as required by the BLM and the WOGCC. Produced 

water will flow from the well pad through buried pipelines to treatment facilities and discharge 

points (see Section 9.0, Water Management). 

Within 365 days of drilling and well completion activities, any remaining reserve pit liquids will be 

removed and disposed of at an approved waste disposal facility. If adverse weather conditions 

prevent removal of the fluids within 365 days, an extension will be requested of the BLM. 

Upon well completion and after the liquid contents of the reserve pit have evaporated or been 

removed, the reserve pit will be reclaimed by filling it with the soil material removed during initial 

pit construction. The area will then be reseeded in accordance with BLM specifications. The 

portion of the well pad not needed for gas production facilities will also be reclaimed in the same 

manner as described above. This reclamation effort will result in a producing well pad size of 

approximately 1.0 acre. 

5.3 Drilling Water 

An average of approximately 7,000 42-gallon barrels of water will be required to drill each well 

(294,000 gallons of water per well). This water will be obtained from the water produced during 

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November 2005 Draft Environmental Impact Statement

drilling and existing dewatering operations. Water used to drill one well may be reused to drill 

subsequent wells. Maximum life-of-project water requirements are estimated to be approximately 

365 million gallons (1,120 acre feet). See further discussion in Section 9.0, Water Management. 

6.0 PRODUCTION OPERATIONS 

Production will involve the following facilities: 

3⁄4 Well Pads (including well sites); 

3⁄4 Gas and Water Gathering and Treatment Systems; 

3⁄4 Compressor Stations; and, 

3⁄4 Gas Gathering Delivery and Terminal Facilities. 

6.1 Well Pads (including well sites) 

Well pads include well site production facilities, which will be installed after well completion to 

facilitate dewatering. This will occur even though commercial gas production may not occur until 

well testing has been completed. See Figure 9, Typical Producing Well Layout, and Section 

9.0, Water Management. 

A Well Completion Report will be filed with the BLM within 30 days of well completion, in 

accordance with 43 CFR 3164. This report will include a facilities/site security diagram. In 

addition, site security procedures will be implemented, as specified in the BLM’s Onshore Oil and 

Gas Order #3. 

Progressive cavity, or submersible pumps will be used to dewater the methane-bearing 

formations. Each well location may include a propane tank of approximately 1,000-gallon capacity 

for emergency operations in the event electric power is unavailable. See Section 11.0, Power. 

Produced water and gas will be separated at the well site, located on each well pad. As 

discussed below, water from each well will be delivered to the water treatment facility and/or 

approved discharge point via an underground infield water gathering pipeline system. See 

Section 6.2, Gas and Well Gathering Systems, and Section 9.0, Water Management. Produced 

gas will be transported from the well through a separate gas gathering pipeline system installed 

beside the underground water gathering pipeline system to a nearby compressor station. See 

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Draft Environmental Impact Statement November 2005

Section 6.2, Gas and Well Gathering Systems, and Section 6.3, Compressor Station. These lines 

will run parallel to access roads to minimize surface disturbance. 

6.2 Gas and Water Gathering Systems 

6.2.1 Gas Lines 

As mentioned above, produced gas from wells will be transported to a centralized compressor 

station via an underground pipeline gathering system. These infield gas-gathering pipelines will 

parallel access roads to minimize disturbance. Infield gas pipelines generally will be 3 to 6” in 

diameter, buried to depths of 4 to 6 feet, which is below expected frost zones, and located 

adjacent to the water lines, electric distribution lines and roads. The estimated total surface 

disturbance associated with gas gathering pipeline construction is set forth in Table A-1, 

Preliminary Estimate of Surface Area Disturbance. 

6.2.2 Water Lines 

As with the gas gathering pipelines, the water gathering lines will be installed within each well pad 

and adjacent to the gas water separator. Water will be piped via 3 to 6 inch diameter pipelines, 

buried at depths of 4 to 6 feet, which is below expected frost zones, and delivered to appropriate 

treatment and discharge systems (see Section 9.0, Water Management). Produced water 

pipelines will typically be located adjacent to the gas pipelines and roads. The estimated total 

surface disturbance associated with water pipeline construction is presented in Table A-1, 

Preliminary Estimate of Surface Area Disturbance. 

6.3 Compressor Stations 

The proposed project will eventually require three compressor stations, which also serve as 

staging locations for construction. Such activity may include, but is not limited to pipe racks, 

pipeline storage, equipment security, dispatch and maintenance. Relatively low-pressure 

wellhead gas from the wells will flow through the infield gathering system to the inlet of one of 

three centrally located dehydration and compressor stations. The purpose of the compressor 

station is to remove residual water vapor from the gas stream and compress the gas for 

placement into a high-pressure gas-gathering pipeline. From the compressor outlets, gas will be 

piped through the gas-gathering pipeline and delivered to the Walcott interconnects. 

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November 2005 Draft Environmental Impact Statement

The three compressor stations will be installed as the gas field is developed. Each station will 

require approximately 10 acres. A planned layout for a compressor station is shown in Figure 10, 

Compressor Station Layout. Plans for building and operating the compressor station in Section 

10, T23N, R85W were discussed in detail in an EA (WY-030-EA2-229) and has been approved 

for construction and operation by the BLM. See Section 2.2, Interconnect Pipeline and 

Compressor Facility. The location of the three compressor stations is shown on Figure 4, 

General Layout Map. The location of the compressor sites will be shifted to account for any 

sensitive wildlife species and to minimize visual impacts. 

Equipment associated with each compressor station will include two 1,000 horsepower 

compressors and a single dehydration unit. See Figure 10, Compressor Station Layout. This 

equipment mostly likely will be housed in a metal, sound reducing building, with a stack 

anticipated no higher than 25 feet and will be painted to blend with the surrounding landscape, 

per BLM specifications. The storage yard will contain a small maintenance building, pipe racks for 

casing, tubing and rods, as well as additional storage space for pumping units, motors, 

separators, miscellaneous valves, fittings, poly pipe and other equipment. 

A pigging launching facility for pipeline maintenance will likely be sited within each compressor 

station storage area. “Pigs” remove any free liquids from the pipeline by “pigging the line” 

regularly. This maintains line efficiency and controls corrosion. 

Prior to the construction of the compressors and dehydration units, soil material will be removed 

from the site and stockpiled for later use in reclamation. The site will be graded for drainage and 

appropriately surfaced. High-use areas will be graveled. The compressor station site will be 

fenced with four-strand barbed wire and equipped with a locked gate. 

A work building will be located at each compressor station location. This building will house an 

office, shop and warehouse. A vehicle-wash facility will be maintained at each site. 

As previously mentioned, a portion of the compressor station site will be used for equipment and 

supply storage. 

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Draft Environmental Impact Statement November 2005

6.4 Pipeline Delivery and Terminal Facilities 

A pig catcher, separator, dehydrator, and associated tanks will be constructed at the southern 

terminus of the high-pressure gas-gathering pipeline where it joins the commercial 

transmission/sale pipeline. Please refer to the related discussion the EA (WY-030-EA2-229) for 

further information. 

7.0 MAINTENANCE ACTIVITIES 

This section discusses maintenance activities on the following project features: 

3⁄4 Roads; 

3⁄4 Compressor Stations; 

3⁄4 Water Treatment Facilities; and, 

3⁄4 Coal Methane Extraction Wells. 

7.1 Roads 

Access roads (see Section 4.1.1, Road Construction) will be maintained to provide year-round 

access to the well pads, compressor stations, and ancillary facilities. Road maintenance will vary 

depending on road usage. Maintenance objectives will include maintaining drainages, resurfacing 

selected segments with gravel, and grading road surfaces. Road maintenance will typically 

involve applying surface materials and grading the roads during the summer and fall months. It 

will also include snow removal during the winter months. To minimize dust, speed limits will be 

set, roads will be surfaced with rock aggregate material (such as gravel), and water/chemical dust 

suppressants will be applied to roads, as appropriate and practical. 

7.2 Compressor Stations 

Compressor facilities will be designed, constructed, and operated to minimize maintenance 

requirements. 

7.3 Water Treatment Facilities 

Water treatment facilities will be designed, monitored and maintained to ensure their effective 

operation. The objective of such maintenance will be to ensure that discharged project water 

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November 2005 Draft Environmental Impact Statement

meets the requirements of the NPDES permit issued and enforced by the WDEQ. See Section 

9.3, Water Treatment and Discharge. 

7.4 Natural Gas Production Wells 

All wells will be maintained regularly and periodic work-overs will be scheduled to maximize well 

production. Details are presented below. 

7.4.1 Operations 

Wells will be operated in a safe manner according to standard industry operating practices. 

Producing wells will require routine maintenance to maximize performance and to detect 

operational difficulties. Each well site will be routinely inspected to ensure operations are 

proceeding safely and efficiently. Inspections will include checking gauges, valves, fittings, and 

other on-site facilities. Routine on-site equipment maintenance will also be performed, as 

necessary. 

7.4.2 Well Site Work-Overs 

Periodic work-overs will be employed to correct any down-hole problems and to ensure that 

producing wells are operating properly. Work-overs will occur on an as-needed basis, to change 

or replace tubing, re-fracture producing formations, clear water and other debris from the wellbore 

and perforations, and/or re-complete a well in additional production zones. Wells will generally 

require several work-overs during the life of the project, with the last work-over being conducted 

when the well is abandoned (see Section 9.2.3, Well Abandonment and Sealing). Work-overs will 

normally take 3 to 5 days and occur during daylight hours. 

8.0 RECLAMATION 

The goal of reclamation is to return disturbed areas to a stabilized and productive condition, and 

to ensure area-wide long-term land and water resources protection. The purpose of interim 

reclamation programs are to stabilize disturbed areas annually following well completion, access 

road construction, water and gas pipeline installation, and electric utility distribution lines burial. 

Reclamation practices, such as those addressed in this document, have been developed and 

successfully utilized for many other oil and gas operations in Wyoming, including The Seminoe 

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Draft Environmental Impact Statement November 2005

Road Coalbed Methane Pilot Project. These practices will mitigate impacts of the proposed gas 

development activities. 

Dudley considers reclamation to be an integral component of the Seminoe Road Project. 

Reclamation will occur in two stages: 

3⁄4 Interim reclamation occurring after well completion, access road construction, infield 

water, gas pipeline and electric utility line installation; and, 

3⁄4 Final reclamation occurring when the project is decommissioned and wells are 

abandoned. 

Specific Seminoe Road Project reclamation program objectives are as follows: 

3⁄4 Re-establish wildlife habitat; 

3⁄4 Re-establish livestock grazing; 

3⁄4 Protect water quality; 

3⁄4 Protect public, livestock, and wildlife by proper well abandonment; and, 

3⁄4 Protect recreational resources found in the area. 

Dudley will prepare specific erosion control, restoration, and revegetation plans for specific areas 

within the Seminoe Road Project during the APD and ROW application process. These plans will 

be approved by the BLM prior to site disturbance. 

8.1 Interim Reclamation 

As part of the Seminoe Road Project road and well site construction activities, Dudley will 

undertake the following to ensure reclamation objectives are met: 

3⁄4 Remove and stockpile soil and cover material, as practicable; 


3⁄4 Implement concurrent reclamation and revegetation programs; 


3⁄4 Reduce well pad site size after drilling to accommodate well production; 


3⁄4 Implement drainage stabilization and erosion controls; and,


3⁄4 Decommission and perform final reclamation of the project site. 


A-18 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

8.1.1 Soil Removal and Stockpiling 

Topsoil or soil suitable for revegetation will be removed from areas used for roads, well pads, or 

compressor station areas. This soil material will be stockpiled for future reclamation. Salvaged 

soil will be stockpiled either in windrows adjacent to the area of its place of origin or placed in 

nearby soil stockpiles. 

Stockpiled soil will be protected as much as possible from wind, water, and other possible 

sources of erosion. During the first normal planting season following the development of a soil 

stockpile, the stockpile will be seeded with a mixture approved by the BLM. 

8.1.2 Interim Stabilization and Revegetation 

Following construction activities, areas such as cut and fill embankments, soil stockpiles, etc. will 

be reseeded to reduce the wind and water erosion potential. To minimize the potential for fire 

hazard, certain areas around compressor stations, storage areas, electrical substations, etc. will 

not be reseeded. Dudley will use a seed mixture approved by the BLM. 

8.1.3 Well Site and Road Reclamation 

After production equipment is installed, the well pad size will be reduced from 2.2 acres to 1 acre, 

the size necessary for production operations. Drilling and other fluids contained in reserve pits will 

be evaporated and covered in place, pursuant to requirements of the BLM and/or WOGCC. 

Material requiring removal will be extracted from the reserve pits and disposed of at an authorized 

location outside the project area (e.g., existing lined evaporation ponds, injector wells or landfills). 

Reseeding will be performed on portions of roads, pipeline ROWs, and well pads which are not 

required for use during production. Those wells not brought into production will be plugged, 

abandoned and reclaimed as per requirements of the BLM and/or WOGCC. 

8.2 Final Closure and Reclamation 

At the time of final and permanent project closure, a number of reclamation steps will occur: 

3⁄4 Decommission facilities; 

3⁄4 Remove structures, facilities and roads; 

3⁄4 Abandon and seal wells; 

Seminoe Road Gas Development Project A-19 
Draft Environmental Impact Statement November 2005

3⁄4 Recontour and regrade disturbed surfaces; 

3⁄4 Replace and mulch soils where necessary; 

3⁄4 Revegetate disturbed areas; and, 

3⁄4 Manage and monitor reclamation efforts. 

8.2.1 Facilities Decommissioning 

Following permanent closure of the operation, equipment, instrumentation, and/or unused 

chemicals and fuels will be removed from the site. The various pipelines will be purged of any 

combustible materials and retired in place. 

8.2.2 Structures, Facilities and Roads Removal 

Except where an ongoing beneficial use is identified, project-related structures, facilities and 

roads will be dismantled and removed from the site once the operation is closed permanently. 

Roads will be ripped to alleviate compaction, and adjacent culverts will be removed. Any 

salvageable structures will be sold. Unsalvageable structures, such as foundations, will be 

removed from the site and disposed of in an approved disposal facility. 

8.2.3 Well Abandonment and Sealing 

When Dudley is ready to abandon a well, an abandonment plan will be submitted to and 

approved by to the BLM, provided it is acceptable. BLM will authorize abandonment activities 

through a Sundry Notice. Wells will be plugged according to BLM Onshore Il and Gas Order #2 

and/or WOGCC rules and regulations. See Figure 18, Conceptual Schematic of Plugged and 

Abandoned Wellbore. 

8.2.4 Recontouring and Regrading 

Disturbed areas, such as roads, and well pads, will be recontoured and regraded, as appropriate, 

to achieve acceptable post-operational topographical conditions. During this phase of project 

closure, high traffic areas, such as roads, will be ripped to alleviate compaction. Culverts will be 

removed from roads to re-establish natural surface drainage patterns. 

8.2.5 Soil Replacement and Mulching 

Following regrading activities, disturbed surfaces will be covered with topsoil material and, where 

necessary, mulched. Topsoil or other suitable material will be replaced to serve as a rooting zone 

A-20 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

for revegetation. Soil material will be applied and the surface will be left in a roughened 

configuration to resist wind and water erosion. This practice will also maximize water retention in 

the replaced soil. Surface manipulation treatments such as ripping and chiseling will be employed 

in heavily compacted areas. Contour furrows and/or contour terraces will be employed and/or 

constructed in areas likely to develop rills and gullies. 

As necessary to initially stabilize the soil, erosion and sedimentation control materials such as 

wood fiber mulch, straw, or erosion control/mulch blankets will be applied in a separate step 

following seeding. 

8.2.6 Permanent Revegetation 

Disturbed sites will be reseeded with a seed mixture approved by the BLM using appropriate 

application methods, such as broadcast seeding, drill seeding, or hydroseeding. 

8.2.7 Reclamation Management and Monitoring 

Newly reclaimed areas will be managed consistent with reclamation goals outlined above. 

Reclaimed sites will be monitored during the first two years after revegetation to ensure erosion is 

prevented and plant species are being re-established. Site maintenance will occur during those 

two years as to ensure that the reclamation program succeeds. 

9.0 WATER MANAGEMENT 

Water management is a key component of the Seminoe Road Project. As explained in Section 

5.0, Drilling Operations, and Section 6.0, Production Operations, water will be produced as a byproduct of gas extraction. 

The following water management considerations are discussed in this section: 

3⁄4 Water use; 

3⁄4 Dewatering operations; 

3⁄4 Water treatment; and, 

3⁄4 Water discharge. 

Seminoe Road Gas Development Project A-21 
Draft Environmental Impact Statement November 2005

9.1 Water Use 

Seminoe Road Project water will be used for drilling operations, dust control, and livestock and 

wildlife watering. 

Drilling operations require water either by itself, or mixed with barite (a natural clay) to make 

drilling mud. This fluid is pumped down the inside of the drill pipe and out through nozzles in the 

drill bit to cool the bit and lift the rock cuttings to the surface. The cuttings return to the surface by 

water or mud flowing up the annulus, which is the space between the outside of the drill pipe and 

the inside wall of the wellbore. The mud flows out onto a shale-shaker and into the mud pits 

where the cuttings drop out of solution and the mud is returned to the pump for another trip 

downhole. Water is often used by itself for drilling the large diameter hole for surface casing, as 

well as the smaller diameter wellbore. 

Water will also be placed on roads during dry months to help control fugitive dust. Livestock and 

a variety of wildlife species will also use the water. 

9.2 Dewatering Operations 

The coals of the western Hanna Basin are water bearing, and the desorption (release) of 

methane gas occurs when the formation hydrostatic pressure is reduced by pumping water out of 

the coal formation through a wellbore. As hydrostatic pressure drops, the physical bond between 

the coal and methane molecules breaks, methane diffuses through the coal into the natural 

fractures and flows with the water stream towards the zone of lower pressure at the wellbore. 

Therefore, to create favorable conditions for the release of methane gas from the coal seams, 

water must be produced prior to and during methane extraction. 

The water production rate from each well is expected to be 1,000 to 1,500 barrels per day 

(42,000 to 63,000 gallons per day or 29 to 44 gallons per minute or 0.06 to 0.10 cubic feet per 

second (cfs)). This range of expected production is derived from the performance of the pilot 

project, as well as technical data. The theoretical maximum, which was calculated from early well 

tests, is about 1,500 barrels per day. The pilot project results to date indicate that peak rates will 

most likely range from 1,000 to 1,200 barrels of water per day due to downhole pump limitations. 

These initial rates will remain constant for up to three months and thereafter decline at 10 to 15% 

A-22 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

annually. Actual discharge from each borehole may be less, depending on geologic conditions, 

pumping equipment limitations, or interference from adjacent wells. 

Produced water volumes will increase as new wells begin producing. While the amount of water 

discharged from individual wells will remain the same or decrease, well density increases will 

cause overall water discharge volumes to increase. 

As with the pilot project operations, the initial pumping rate of 1,000 to 1,500 barrels of water per 

day (29 to 44 gallons per minute or 0.06 to 0.10 cfs) will remain constant for up to three months 

and decline thereafter at 10 to 15% annually. As a result, daily water production during the buildout will stabilize in the fourth or fifth year to a level of approximately 180,000 barrels of water per 

day (5.250 gallons per minute (gpm) or 12 cfs). This level is projected to remain constant for a 

period of nine to ten years then decline (because no additional wells will be established). At this 

point, water production will continue to decline for the remainder of the project life. 

The pumping equipment used for the dewatering actions of the project will be the same type 

generally used by the petroleum industry to produce liquids. This equipment includes, but is not 

limited to progressive cavity pumps and electric submersible pumps. 

Progressive cavity pumps are also commonly used, particularly in coalbed methane production. 

These pumps contain a rotor (metal road with corkscrew shape) inside a stator (hardened rubber 

with a corkscrew interior for the rotor) that rotates to work pockets of water from the bottom to the 

top. 

Electric submersible pumps are less common in coalbed methane production applications, but 

they can handle greater water production rates if necessary to effectively dewater the coals. 

Dudley will obtain all necessary dewatering permits, as well as any water right appropriations for 

produced waters, from the Wyoming State Engineer’s Office. 

9.3 Water Treatment and Discharge 

The planned method for produced water disposal from the build-out will be similar to that currently 

employed by the pilot project. Dudley prepared a detailed Water Management Plan for the pilot 

project. This plan, revised April 2001, is on file with the BLM Rawlins Field Office. In addition, 

water produced from the pilot project wells is regulated under an NPDES permit issued from the 

Seminoe Road Gas Development Project A-23 
Draft Environmental Impact Statement November 2005

WDEQ (NPDES Permit WYW004-1807), as discussed in Section 1.0, General Project 

Description. 

Currently, Dudley uses three approved discharge points, pursuant to the aforementioned NPDES 

permit. At the appropriate time during the proposed build-out, Dudley will seek to modify its 

NPDES Permit to allow for up to fifteen additional discharge points. The Wyoming DEQ could 

revise discharge standards on future discharge points. 

Seminoe Road Project produced water will be transported from well locations via buried water 

pipelines that will generally be located parallel to the roads and placed in the same trench as the 

gas pipelines. 

Dudley has collected water quality samples from wells since 2001 and analyzed water discharge 

from the pilot project since 2002. Discharges from the Pilot Project comply with the all applicable 

NPDES permit limits and conditions. The pilot project discharge water meets drinking water 

standards, and the quality of this water has improved during the sample period of record, 

particularly for barium and iron. 

The discharge water type is sodium chloride, with a slightly alkaline pH and moderately elevated 

total dissolved solids (TDS) concentrations. The water has generally low concentrations of trace 

constituents, with the exception of chloride, iron, manganese, and barium. The water has a 

sodium adsorption ratio (SAR) that is higher than the Wyoming agricultural standard. 

During the build-out, Dudley will install water treatment facilities similar to those presently utilized 

for the pilot project in a manner that ensures compliance with NPDES permit limits and 

conditions. A schematic of a typical water treatment facility (as is being used for the pilot project) 

is illustrated on Figure 11, Water Treatment Facilities Layout. 

Produced water will be routed from the wells into aeration tanks, designed to remove dissolved 

iron from the water stream to prevent any iron staining downstream of discharge points. From the 

aeration tanks, water will be routed into filter tanks that trap and remove any iron and manganese 

particles. The filter tanks use a combination of sand and gravel to facilitate the filtration process. 

Once water passes through the filtration tanks, it will be routed to a discharge point. Outfall 

structures for the water discharge will consist of energy dissipaters and rock riprap to minimize 

erosion at the point of discharge. 

A-24 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Water treatment facilities and NPDES discharge points will be installed at strategic locations 

within the project area. See Figure 12, Produced Water Discharge Points – Alternative B. 

With one exception, water released at project discharge points will flow down various drainages, 

which are tributaries of the Seminoe Reservoir. The exception will be in the project area south of 

the Seminoe Reservoir, where discharge water will be routed into three closed basin playas. 

From here, the water will simply evaporate. 

10.0 POWER 

Presently propane-fired engines are used to run Pilot Project generators at individual wells. 

However, the Seminoe Road Project build-out plans call for eventual electrification of the entire 

field. 

During the first two years of the build-out (2006-2007), Dudley will continue using propane or 

natural gas fired engines at the well sites. This is the anticipated time frame for substation 

construction and installation of buried electric distribution lines burial. These lines, occurring 

between the substation and well sites, will be placed in trenches alongside the roads and infield 

gas and water lines. Throughout the project build-out, there would be a need for propane or 

natural gas powered engines at out-lying well sites. 

The electricity will come from the existing Western Area Power Authority (WAPA or Western) 115 

kV transmission line located within the EIS analysis area (on the west side of Seminoe Road). 

Because WAPA is a part of the U.S. Department of Energy and is not a provider of retail 

electricity sales, Dudley will need to purchase the power from a local district distribution company 

(probably PacifiCorp). 

A high-voltage substation will be constructed to accept power from the existing WAPA 115 kV 

transmission line. This substation will be located at the previously approved compressor station 

located in Section 10, Township 23 North, Range 85 West. See Figure 4, General Layout Map. 

An approximate 8,000-foot overhead transmission line extension will be constructed from the 

WAPA 115 kV line to the substation. This extension line will be built using standard industry 

procedures and will follow guidelines established to prevent raptor electrocution. 

Seminoe Road Gas Development Project A-25 
Draft Environmental Impact Statement November 2005

Low-voltage substations will be installed at the other two proposed compressor sites. See Figure 

4, General Layout Map. The electric distribution lines that feed the two low-voltage substations, 

as well as the electric distribution lines to the well pad sites will be buried next to access roads in 

the same right-of-way used for the gas and water pipelines. 

Dudley will maintain up to five portable propane or natural gas fired engines on site to serve well 

pad operations during emergency situations where electric power is disrupted. 

11.0 WORK FORCE 

The construction and well development phases of the Seminoe Road Project will require a work 

force of 70 to 90 people. These phases are estimated to occur during the first 9 years of build-out. 

Work included in these phases involves pre-construction/site surveying, well pad and access road 

construction, well drilling and completion, and gas and water pipeline installation. Dudley will 

manage the construction and well development phases; however the actual work will be 

subcontracted to construction and drilling firms that specialize in this type of work. Dudley 

estimates that approximately 50% of this work force will be hired locally, within Carbon County. 

As the project operations phase begins, Dudley will require a fulltime work force. This workforce 

will handle day-to-day operations, including routine maintenance. Dudley estimates that a peak 

operating and maintenance work force of approximately 40 to 60 people would be employed. This 

work force would be needed throughout the projected 30-year life of project term. Dudley 

estimates that approximately 80% of this work force will be hired locally within Carbon County. 

Decommissioning and reclamation activities will require approximately 30 to 50 people. Dudley 

will manage this work using subcontractors that specialize in reclamation activities. Dudley 

estimates that approximately 95% of this work force will be hired locally within Carbon County. 

12.0 TRANSPORTATION/TRAFFIC 

Work force personnel will commute each workday to and from the site. They will do so from 

various locations (Rawlins, Sinclair, Hanna, etc). Dudley expects that approximately 50% of the 

work force will carpool to the site, with personnel being free to choose how they commute. 

Carpooling will result in less traffic. 

A-26 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Materials required for operations, including drilling supplies, piping and fuel will be delivered to 

the site by truck from various locations (Rawlins, Cheyenne, Rock Springs, and from outside the 

State of Wyoming). During peak drilling operations, Dudley expects there will be approximately 15 

to 20 weekly trips required to deliver bulk materials, resulting in an estimated 3 to 4 truck trips per 

day. 

Both work force and supply traffic will access the site via the Seminoe Road (Carbon County 

Road 351). This road is a two-lane, blacktop road that runs south from the project site 

approximately 18 miles to the Town of Sinclair, Wyoming. It has recently been widened and 

resurfaced. Interstate 80, runs adjacent to Sinclair and is a major four-lane federal highway that 

crosses southern Wyoming. The southern portion of the project area will be accessed at Walcott, 

Wyoming, from Interstate 80. 

13.0 APPLICANT-COMMITTED MITIGATION AND MANAGEMENT 

MEASURES FOR ENVIRONMENTAL PROTECTION 

For the pilot project, Dudley adopted a host of mitigation and management measures to ensure 

minimal environmental impacts. The following elements of an environmental impacts mitigation 

and management program will also be employed for the Seminoe Road Project. Dudley’s 

adherence to this program will ensure that the project site remains productive for multiple uses 

both during and following final project closure and decommissioning. 

Dudley will incorporate environmental management and mitigation measures into Seminoe Road 

Project operations. These measures will be employed with certain refinements evolving from the 

alternatives BLM selects at the end of this EIS process. Furthermore, BLM may identify additional 

site-specific mitigation/management measures during the APD and ROW application processes, 

which will occur subsequent to the Record of Decision on this EIS. Dudley will also be subject to 

additional operating requirements, including permit limits and conditions, emanating from other 

applicable regulations administered and enforced by other local, state and federal government 

agencies. 

BLM may waive mitigation/management measures and design features identified in this 

document if, after thorough analysis, the agency determines that the resource(s) for which the 

measure was developed will not be impacted and/or alternative BLM-approved measures of 

guidance for protecting the resource(s) are developed. 

Seminoe Road Gas Development Project A-27 
Draft Environmental Impact Statement November 2005

Environmental mitigation and management program elements for the Seminoe Road Project are 

discussed in this section as follows: 

3⁄4 Pre-construction Planning and Design; 

3⁄4 Sewage, Trash and Other Waste Material; 

3⁄4 Cultural and Historic Resources; 

3⁄4 Paleontological Resources; 

3⁄4 Vegetation; 

3⁄4 Noxious Weeds; 

3⁄4 Road Construction and Transportation; 

3⁄4 Chemicals and Hazardous Materials; 

3⁄4 Air Quality; 

3⁄4 Topography and Physiography; 

3⁄4 Soils; 

3⁄4 Water Resources; 

3⁄4 Wetlands, Other Special Aquatic Sites, and Waters of the U.S.; 

3⁄4 Noise and Odor; 

3⁄4 Wildlife and Fisheries; 

3⁄4 Threatened, Endangered, Proposed, Candidate and Sensitive Species; 

3⁄4 Livestock and Grazing Management; 

3⁄4 Socioeconomics; 

3⁄4 Land Status, Use and Access; 

3⁄4 Recreation; 

3⁄4 Visual Resources; and, 

3⁄4 Health and Safety. 

13.1 Pre-construction Planning and Design 

Prior to construction, Dudley will submit a “Plan of Development” (POD) for each well pad, 

pipeline segment, and access road, or groupings of such project features. Well pad locations and 

the routing of associated access roads/pipelines/electric utilities will be selected and designed to 

A-28 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

minimize disturbance to areas of high wildlife habitat and/or recreational value, including riparian 

areas. In this effort, Dudley will work with both the BLM and the private landowners. 

Following submittal of each POD representatives from Dudley and the BLM will conduct an onsite inspection of proposed disturbance sites (e.g., well pads, roads, pipelines, electric utility lines, 

etc.) to finalize site-specific recommendations and mitigation measures. BLM will consult with the 

Wyoming Game and Fish Department (WGFD), the U.S. Fish and Wildlife Service (USFWS), and 

the State Historic Preservation Office (SHPO), as appropriate, where construction activities might 

affect restricted areas and/or, when the timing of such construction activities might occur during 

periods of wildlife restrictions. 

13.2 Sewage, Trash and Other Waste Material 

Portable self-contained chemical toilets will be provided for human waste disposal. Upon 

completion of drilling activities, or as required, toilet holding tanks will be pumped and their 

contents disposed of at an approved sewage facility in accordance with applicable rules and 

regulations regarding sewage treatment and disposal. 

Garbage and non-flammable waste materials will be collected in self-contained portable 

dumpsters or trash cages and hauled off site to an approved sanitary landfill. No trash will be 

placed in the reserve pit at the well pad locations, nor will any open burning of garbage and 

refuse be allowed on the project area. As soon as practical after removal of the drilling rig, debris 

and other waste material not contained in the trash cage or dumpsters will be cleaned up, 

removed from the well sites, and disposed of at an approved sanitary landfill. No potentially 

harmful materials or substances will be left on the project site. 

13.3 Cultural and Historic Resources 

Class III inventories will be conducted prior to disturbance on all federal lands and on state and 

private lands affected by construction and operations, unless private landowner denial for access 

is documented in writing. 

Dudley and its contractors will inform their employees about relevant federal regulations 

protecting cultural resources. Dudley will adhere to the requirements of the National Historic 

Preservation Act of 1966 (as amended) and the Archaeological Resource Protection Act of 1979, 

Seminoe Road Gas Development Project A-29 
Draft Environmental Impact Statement November 2005

in particular, specific BLM and SHPO recommendations prior to construction activities near 

known historic sites (e.g., cabins, grave sites, etc.) or any prehistoric sites within the project area. 

Any objects of historic or cultural interest discovered during construction and operation will be 

brought to the attention of the responsible BLM official immediately. Dudley will halt construction 

activities in potentially affected areas in the event that previously undetected cultural resource 

properties are discovered during construction. The BLM will consult with the SHPO as necessary. 

Proper mitigation measures will be developed, and construction in the affected area will not 

resume until authorized. 

13.4 Paleontological Resources 

Any objects of paleontological interest discovered as a result of construction will be brought to the 

attention of the BLM. Construction activities in the affected area will cease immediately, until 

appropriate clearances are issued by the BLM. 

13.5 Vegetation 

Removal or disturbance of vegetation will be kept to a minimum by using previously disturbed 

areas wherever possible (including existing ROWs) and by limiting the area used by 

equipment/material storage yards and staging areas. Vegetation and soil removal will be occur in 

a manner that minimizes erosion and sedimentation. Disturbed areas will be stabilized and 

reseeded in accordance with BLM approved guidelines and/or private ownership specifications. 

See Section 8.0, Reclamation and Decommissioning. 

13.6 Noxious Weeds 

Dudley will be responsible for controlling noxious weeds along road ROWs, at well sites, and 

within any other areas disturbed by the project. The list of noxious weeds requiring control will be 

obtained from the BLM and/or the Carbon County Weed and Pest Office. Hand pulling/ digging, 

biological control (e.g. goats), and/or application of approved herbicides will be used for control of 

noxious weeds, as appropriate. Only BLM-approved herbicides will be used. Herbicide 

applications will be kept at least 500 feet from any known special status plant populations. 

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November 2005 Draft Environmental Impact Statement

13.7 Road Construction/Transportation 

Roads will be constructed specifically to support field development and operations, with the 

option of considering private landowner needs. Access road location and design will be 

considered and approved by BLM before any ground disturbing activities occur. Roads will be 

designed to minimize surface disturbance wherever possible. Existing roads will be used and 

upgraded where possible for the same reason. Roads that loop will be discouraged to minimize 

surface disturbance and vehicle traffic. Road access to well sites will be designed to maximize 

directness and shortness in length, wherever possible. 

Standard BLM design and construction procedures as outlined in the BLM Manual, Section 9113 

(Roads), and in the “Gold Book” Oil and Gas Surface Operating Standards for Oil and Gas 

Exploration and Development, 3rd Ed. for oil and gas access roads will be employed for road 

development, unless other identifiable and safe design options causing cause less surface 

disturbance are approved by BLM. 

Available soil material (up to 12 inches) will be removed from road corridors prior to construction 

activities. This material will be windrowed or stockpiled for later redistribution on back slope areas 

of the borrow ditch. Borrow ditches will be reseeded in the first appropriate season after initial 

disturbance. 

Roads will be constructed with adequate drainage and erosion control structures, such as relief 

culverts, drainage culverts, wing ditches, etc. Roads will be built, surfaced, and maintained to be 

safe. Roads in rough terrain or areas of high erosion potential will be designed and monitored 

during construction by a professional engineer. Areas disturbed for road construction will be 

minimized to reduce impacts and therefore the needs for reclamation. All road construction 

activities will be restricted to areas authorized in the approved ROWs. 

Dudley will maintain roads in a safe, useable condition. A regular maintenance program will 

include activities such as blading, ditching, culvert and cattle guard maintenance/replacement, 

and re-surfacing, as needed. Dudley and its contractors will comply with existing federal, state, 

and county requirements and restrictions with regard to transportation. During drilling and 

operation, traffic will be restricted to Carbon County Road 351 and roads developed for the 

project. Off-road travel or use of unimproved roads will be allowed only in emergency situations. 

Seminoe Road Gas Development Project A-31 
Draft Environmental Impact Statement November 2005

Speed limits will be set commensurate with road type, traffic volume, vehicle types, wildlife 

stipulations and site-specific conditions, as necessary, to ensure safe and efficient traffic flows. 

As necessary, signs will be placed along roads to identify speed limits, travel restrictions, and 

other standard traffic control information. In addition, newly developed or improved roads through 

critical wildlife habitats will be gated and locked as directed by the BLM to prevent unnecessary 

wildlife disturbances. 

Following permanent project closure and production activities, Dudley will close and reclaim 

roads. 

Dudley and its contractors will comply with requirements of the Wyoming Department of 

Transportation and Carbon County for any oversize or over weight loads. Special arrangements 

will be made with the Wyoming Department of Transportation and/or Carbon County to transport 

any oversized loads to the project area. 

13.8 Chemicals and Hazardous Materials 

Dudley and its contractors will manage chemicals and hazardous materials in a manner that 

complies with applicable federal, state, and local regulations. 

Dudley and its contractors will transport, locate, handle, store and use regulated hazardous 

materials in an appropriate manner that protects workers and the public, as well as preventing 

accidental releases to the environment. 

Dudley will develop, and use as necessary, a Spill Prevention Control and Countermeasure Plan 

(SPCC) for the operation as required by the Federal Oil Spill Prevention regulation (40 CFR 112) 

as administered by the Environmental Protection Agency (EPA). In the SPCC, Dudley will identify 

a spill response program that includes overall management objectives, instrumentation and 

equipment needs, response actions, monitoring and reporting requirements, and general safety 

considerations for employees, contractors, and the general public. Copies of the SPCC plan will 

be given to appropriate Dudley personnel, contractors, and field personnel. This plan will also be 

kept on file at Dudley’s Denver, Colorado office. 

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November 2005 Draft Environmental Impact Statement

13.9 Air Quality 

Dudley will meet all applicable state and federal air quality standards. This will mean compliance 

with applicable Wyoming ambient air quality standards (WAAQS), National Ambient Air Quality 

Standards (NAAQS), permit requirements (including pre-construction, testing, and operating 

permits), and other applicable regulations, as required by the WDEQ, Air Quality Division. 

13.10 Topography and Physiography 

Areas with high erosion potential and/or rugged topography, such as steep slopes, stabilized 

sand dunes, floodplains, and unstable soils, will be avoided where possible. Special mitigation 

measures to control erosion will be applied to such areas if they are disturbed. 

Upon completion of construction and/or production activities, Dudley will restore the topography 

to near pre-existing contours at well site locations, facilities, corridors, pipelines, and other facility 

sites. 

13.11 Soils 

Soil material will be removed during the construction operations in sufficient quantities to achieve 

reclamation plan objectives. Soil stockpiles will be seeded or otherwise protected to prevent 

erosion. 

Dudley will restrict off-road vehicle activity by employees and subcontractors. Dudley will 

minimize project related travel during periods when soils are saturated and excess road rutting 

(e.g., greater than 6 inches) may occur. The area of disturbance will be kept to the minimum 

needed for drilling activities and subsequent production activities while still providing for safety. 

Pipelines will be located adjacent to roads or other pipelines to avoid creating additional areas of 

disturbance. 

Cut and fill slopes for well pads and access roads will be designed to prevent soil erosion. 

Disturbed slopes will be revegetated, mulched, or otherwise stabilized to minimize erosion as 

soon as practicable following construction. Soil material will be replaced over disturbed surfaces 

prior to permanent revegetation. 

Seminoe Road Gas Development Project A-33 
Draft Environmental Impact Statement November 2005

13.12 Water Resources 

Dudley will adhere to the limits and conditions contained in any NPDES permit issued by the 

WDEQ, Water Quality Division. Project actions will be conducted in compliance with this permit. 

Dudley will limit disturbance within drainage channels, including ephemeral and intermittent 

draws, where practical. Surface disturbance to perennial surface water (and/or wetland and 

riparian areas) will be avoided, where practical. In addition, any crossings of ephemeral, 

intermittent and perennial streams will be made perpendicular to flow where practical. 

Where riparian areas must be disturbed, the following measures will be employed: 

3⁄4 Construction across riparian areas will occur during dry conditions (i.e., late summer, fall, 

or dry winters). 

3⁄4 Riparian areas disturbed during project construction will be restored as near as 

practicable to pre-project conditions. If impermeable soils contributed to riparian area 

formation, soils will be compacted to re-establish that state. 

3⁄4 Riparian area topsoil will be selectively handled. 

3⁄4 Recontouring and BLM-approved plant species will be used to revegetate any disturbed 

riparian areas. 

3⁄4 Revegetation operations will begin on affected areas in the first appropriate season after 

completion of project activities. 

Discharge of water will conform to the rules and regulations of the BLM, WOGCC, and the 

WDEQ, Water Quality Division. Current water uses on and adjacent to the project area will be 

protected, and project activities will be conducted to prevent adverse effects on water quality and 

quantity. 

The casing and cementing criteria for wellbore plugging, as established by the BLM and 

WOGCC, will be implemented to protect subsurface water bearing zones in accordance with 

standard oil field practices. 

A-34 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

13.13 Wetlands, Other Special Aquatic Sites, Other Waters of the U.S. 

Wetlands and Other Waters of the U.S. are regulated under Section 404 of the Clean Water Act. 

Dudley will avoid these sensitive areas wherever practical. If wetlands or other special aquatic 

sites, riparian areas, streams, and WDEQ Section 401, Ephemeral/Intermittent Stream Channels 

are likely to be disturbed, Dudley will obtain the necessary Section 404 permits and 

authorizations and apply appropriate mitigation measures. 

13.14 Noise and Odor 

Internal combustion engines associated with the Seminoe Road Project will be maintained and 

muffled to minimize noise and odor. 

13.15 Wildlife and Fisheries 

Reserve pits or other project-related impoundments potentially hazardous to wildlife will be 

adequately protected (e.g., fenced or netted) to prohibit wildlife access and to ensure protection 

of migratory birds and other wildlife, as directed by BLM. 

Dudley will implement policies designed to control poaching and littering and will notify all 

employees and subcontractors that conviction of a major game violation may result in disciplinary 

action. Contractors will be informed that any intentional poaching or littering within the project 

area may result in dismissal. 

Proposed disturbance within 0.5 mile of identified raptor nests will require survey by a qualified 

biologist to determine nest activity status prior to commencement of drilling and construction 

during the raptor-nesting period. If an active raptor nest is identified within 0.5 mile (depending on 

species and line of sight) of a proposed site, Dudley will restrict construction during the critical 

nesting season for that species. 

Known active sage grouse leks and adjacent (2-mile radius from lek centers) public land areas 

will be avoided during the breeding and nesting season (March 1 – June 30). No construction 

activities will occur on public lands within 0.25 mile of known active sage grouse lek sites. 

Construction activities on public lands in sage grouse nesting habitat and within 2.0 miles of 

active sage grouse leks will not occur without a BLM-approved biologist first surveying for sage 

grouse nests. If a nest is found, the area will be avoided until after nesting is complete. 

Seminoe Road Gas Development Project A-35 
Draft Environmental Impact Statement November 2005

13.16 Threatened, Endangered, Proposed, Candidate and Sensitive Species 

Dudley will implement requirements outlined in the USFWS Biological Assessment (BA) for any 

threatened, endangered, proposed, or candidate species found in the project area. Similarly, 

Dudley will implement any BLM requirements concerning BLM sensitive species. 

13.17 Livestock/Grazing Management 

Dudley will coordinate project activities with ranching operations to minimize conflicts with 

livestock movement or other ranch operations. Dudley will maintain fences, cattle guards, and 

other existing livestock related structures. In areas of high livestock use, Dudley will fence 

reclaimed areas, as necessary, to ensure successful revegetation. 

13.18 Socioeconomics 

Dudley will implement hiring practices that encourage the use of local contractors and workers, 

using the local job service center, as necessary, and only going outside the region to hire if an 

adequate pool of candidates cannot be generated. 

13.19 Land Status Use/Access 

Dudley will minimize disturbance by maintaining as compact an operation as possible. Roads, 

power lines, and pipelines will be located adjacent to existing compatible linear facilities where 

practical. All abandoned wells will be plugged utilizing BLM, WOGCC, and WDEQ procedures 

designed to protect subsurface aquifers. 

13.20 Recreation 

Only authorized travel will be allowed into the project area. No unauthorized vehicles, personnel, 

or firearms will be permitted on the site. Plans will be implemented to control public access, such 

as fencing, gate locking or notice posting to prohibit unauthorized entry. Dudley will also inform 

their employees, contractors, and subcontractors that long-term camping (greater than 14 days) 

is prohibited on federal lands or at federal recreation sites. 

13.21 Visual Resources 

Seminoe Road Project surface facilities will be designed to preserve the view shed from the 

Seminoe Road and Seminoe Reservoir; and to conform to standards for applicable BLM visual 

A-36 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

resource management requirements. External lighting will be kept to the minimum required for 

safety and security purposes. Facilities will be painted to blend with the surrounding landscape. 

13.22 Health and Safety 

Dudley will consider worker safety as the highest priority of Seminoe Road Project construction 

and operation. Well and pipeline installations will meet reliability and safety standards set by 

federal, state and local government agencies. Adherence to such standards will minimize or 

prevent hazards to Dudley’s employees, contractors, and the public and ensure a high level of 

system reliability. 

Seminoe Road Gas Development Project A-37 
Appendix B 

The NEPA Process 
November 2005 Draft Environmental Impact Statement 

Contents

1.0 Introduction..................................................................................................... B-1

2.0 The EIS Process ................................................................................................ B-2

2.1 Scoping................................................................................................................ B-2

2.2 Analysis Action .................................................................................................... B-4

2.2.1 Collection and Interpretation of Baseline/Background Information............B-4

2.2.2 Development of Alternatives ....................................................................... B-4 

2.2.2.1 No Action Alternative ............................................................................ B-5

2.2.2.2 Action Alternatives ................................................................................B-5

2.2.3 Estimate of Effects of Each Alternative .......................................................B-6

2.2.4 Evaluation of Alternatives ............................................................................ B-6

2.3 Documentation ...................................................................................................B-6

2.4 Implementation, Mitigation and Monitoring.......................................................B-6

3.0 Public’s Role in the Process............................................................................. B-7

4.0 Role of Government Agencies and Private Entities ....................................... B-7

4.1 Lead Agency........................................................................................................ B-8

4.2 Cooperating Agencies .........................................................................................B-8

4.3 Project Proponent ..............................................................................................B-8

4.4 Independent Third-Party Contractor ..................................................................B-9

4.5 Interested Agencies ..........................................................................................B-10

5.0 EIS Mailing List ............................................................................................... B-11

Seminoe Road Gas Development Project B-i 
November 2005 Draft Environmental Impact Statement 

Appendix B – The NEPA Process 1 

1.0 Introduction 

Congress passed the National Environmental Policy Act (NEPA) in 1969 as the “National Charter 

for the Protection of the Environment” (40 CFR 1500.1). BLM management activities are subject 

to the provisions set forth in the law. 

NEPA is “intended to help public officials make decisions that are based on an understanding of 

environmental consequences.” Projects requiring a permit from a federal agency must meet NEPA 

requirements. 

There are three levels of project analysis available to deciding officials: 

(1) Categorical Exclusions 

(2) Environmental Assessments 

(3) Environmental Impact Statements 

Categorical exclusions (CE) are used for routine projects with little risk of environmental effects, 

and in some emergency situations. Environmental assessments (EA) are used to determine if a 

proposed project may have significant environmental effects. If the significance finding in an EA 

is positive, an environmental impact statement (EIS) must be prepared. 

The BLM determined the proposed Seminoe Road Project might have significant environmental 

effects as defined under the NEPA; therefore, the BLM decided to prepare an EIS for the Seminoe 

Road Project. 

A discussion of the responsibilities of the BLM, as well as other federal, state, and local agencies, 

with regard to coalbed methane extraction activities, is set forth in Appendix D, Agency 

Jurisdictions (Permits and Approvals). 

1 This appendix was included to assist individuals and organizations with an overview of NEPA. During the 

scoping process, there were many questions and misunderstandings about NEPA, its process, and how this 

law would be applied to the Seminoe Road Project. 

Seminoe Road Gas Development Project B-1 
Draft Environmental Impact Statement November 2005 

2.0 The EIS Process 

The environmental analysis actions leading to a final EIS are prescribed by NEPA and consist of 

the following: 

3⁄4 Scoping; 

3⁄4 Analysis Actions; 

3⁄4 Documentation; and 

3⁄4 Implementation, Mitigation and Monitoring. 

2.1 Scoping 

The scoping process determines the extent of the environmental analysis necessary for a decision 

on a project. Elements of the scoping process include the following: 

3⁄4 Describe the proposed action; 

3⁄4 Collect existing data and information about the project and general area; 

3⁄4 Initiate public participation in the EIS process; 

3⁄4 Determine the type and extent of analysis to be used in EIS preparation; 

3⁄4 Identify and initiate contact with involved government agencies and the appropriate 

responsible officials from each agency; 

3⁄4 Prepare plans for the preparation of the draft and final EIS, including selection of a formal 

organization for the document;


3⁄4 Develop a tentative schedule for EIS completion and publication; and,


3⁄4 Narrow the scope of the EIS to key issues.


As part of scoping, the BLM often cultivates discussions with private citizens, concerned and 

special interest groups, and government agencies regarding the proposed project. 

On March 13, 2003, a Notice of Intent (NOI) to prepare an EIS for the Seminoe Road Project was 

published in the Federal Register; this notice officially began the 60-day scoping period for the 

project. In addition, the BLM placed notices in local papers and mailed “interested parties” letters 

B-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

to its Rawlins NEPA mailing list announcing the preparation of an EIS for the Seminoe Road 

Project. See Section 5.0, Rawlins BLM NEPA Mailing List. 

The BLM further hosted public scoping “open house” meetings in Hanna, Wyoming on May 7, 

2003 and in Rawlins, Wyoming on May 8, 2003, and the following individuals attended: 

May 7, 2003 – Hanna, Wyoming May 8, 2003 – Rawlins, Wyoming 

Dwight France Art Zeiger 

B.J. Kristanson Jeff Matney 

Bill Nation Bill Nation 

Margo Dally Bill Shaffer 

Fred Kelly Tim Mullen 

Scott Burgess 

Steve Olsen 

Jessie Spehar 

Ed Griebel 

Glendon Merrell 

John France 

The BLM received eighteen comment letters on the Seminoe Road Project from the following 

agencies, organizations, and individuals: 

3⁄4 U.S. Department of Health & Human Services – Public Health Service 

3⁄4 USDA Forest Service – Bridger Teton National Forest 

3⁄4 U.S. Department of Energy – Western Area Power Administration 

3⁄4 U.S. Fish & Wildlife Service 

3⁄4 Environmental Protection Agency 

3⁄4 Office of the Governor – State of Wyoming 

Seminoe Road Gas Development Project B-3 
Draft Environmental Impact Statement November 2005 

3⁄4 Wyoming Game & Fish Department 

3⁄4 Wyoming Department of State Parks & Cultural Resources 

3⁄4 Wyoming DEQ - Air Quality Division 

3⁄4 Southern Ute Indian Tribe 

3⁄4 Petroleum Association of Wyoming 

3⁄4 Biodiversity Conservation Alliance – Wyoming Outdoor Council 

3⁄4 Miller Estate Company 

3⁄4 Anadarko E & P Company LP 

3⁄4 Dwight H. France 

3⁄4 Barbara Parsons 

The comments from these letters were used to help identify the issues listed in Chapter 1, 

Purpose of and Need for Project, of the this EIS. 

2.2 Analysis Action 

Based on the scoping efforts, the BLM analyzed the nature and significance of the physical, 

biological, and socioeconomic effects of the proposal and reasonable alternatives. 

2.2.1 Collection and Interpretation of Baseline/Background Information 

Data collection and interpretation for the Seminoe Road Project was focused on the present and 

expected physical, biological, and socioeconomic conditions affecting or affected by the proposal. 

The BLM reviewed and analyzed environmental data and information to ensure adequacy and 

accuracy. 

2.2.2 Development of Alternatives 

Besides the proposed action, an EIS must address a No Action Alternative and consider other 

alternatives. 

B-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

2.2.2.1 No Action Alternative 

NEPA requires that a “No Action” Alternative be considered in EIS documents. This alternative 

serves as the baseline for estimating the effects of action alternatives. The baseline for the 

Seminoe Road EIS is the existing condition of the environment today. This accounts for the 

existing Seminoe Road Pilot Project and the approved transport pipeline. Under this alternative, 

the proposed coalbed methane “build-out” project on federal lands would be denied. 

2.2.2.2 Action Alternatives 

As part of the EIS process, alternatives are reviewed. Social and environmental issues, concerns, 

and opportunities are considered in this review. In developing project alternatives for consideration 

in the EIS, numerous location, operational methods, and mitigation measures are examined. The 

type and range of alternatives are determined from public comments and key issues that have 

been identified during the scoping process, by reviewing the purpose of and need for 

development, and determining unresolved conflicts involving alternate uses of available 

resources. 

The actual analysis of alternatives is included in the draft EIS and includes a discussion of 

environmental protection measures, mitigation requirements, and operational constraints. Review 

of alternatives and understanding of key issues serve as the foundation to meeting the mandate of 

NEPA. 

In 40 CFR 1500.1(b), it is stated: 

NEPA procedures must ensure that environmental information is available to public 

officials and citizens before decisions are made and before actions are taken. The 

information must be of high quality. Accurate scientific analysis, expert agency 

comments, and public scrutiny are essential to implementing NEPA. Most important, 

NEPA documents must concentrate on the issues that are truly significant to the 

actions in question, rather than amassing needless detail. 

The BLM gathers both public and government input as part of the scoping process. The Record of 

Decision from the BLM must be based on input from the public and numerous federal, state, and 

local governmental authorities. 

Seminoe Road Gas Development Project B-5 
Draft Environmental Impact Statement November 2005 

2.2.3 Estimate of Effects of Each Alternative 

Direct, indirect, and cumulative effects of the proposed actions are considered. Effects are 

described in terms of changes in the physical, biological, and socioeconomic environment. These 

changes are also described by the magnitude, duration, frequency, reversibility, and significance 

of the effects. 

2.2.4 Evaluation of Alternatives 

Alternatives are compared on the basis of its impacts on the environment and socioeconomic 

considerations. This evaluation provides a means of identifying the preferred alternative. 

Evaluation methods include the use of environmental controls and operational technology as 

mitigation measures and management considerations to the proposed action. 

2.3 Documentation 

The BLM documents the EIS process by maintaining an administrative record. Documentation 

includes the Notice of Intent to prepare the EIS, scoping information, Notices of Availability for the 

draft and final EIS, the draft and final EIS documents, the Record of Decision, and supporting 

reference materials. 

2.4 Implementation, Mitigation and Monitoring 

The BLM reviews input and comments on the draft EIS from the public and interested federal, 

state, and local government authorities prior to publishing a final EIS. 

Proposed development within a project area on public lands is subject to a finding that such 

development is consistent with the current BLM resource management plan (RMP) for the region. 

Although the Seminoe Road Project area is presently being managed under the 1990 Great 

Divide RMP, this 1990 RMP is currently being revised under the title of Rawlins RMP. The 

Seminoe Road Project EIS and the Rawlins RMP revision have overlapping schedules; therefore, 

where possible, the information and analyses needed for these planning efforts are being used for 

both EIS documents. 

Based on comments received on the Seminoe Road Project draft EIS process, the Proponent may 

elect to modify their proposal before release of the final EIS in order to respond to certain 

B-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

concerns. In addition, the BLM may modify an action alternative or create a new alternative for 

analysis in the final EIS. 

Once alternatives analysis is completed in the final EIS, a Record of Decision (ROD) would be 

published by the BLM for the project and would render a decision on the project. The ROD is the 

findings document for the EIS. The ROD would include specific monitoring and mitigation 

stipulations for the project. If an action alternative is approved in the ROD, the BLM and other 

federal agencies will consider the final EIS when specific approvals and permits are being 

considered and may attach additional approval conditions or stipulations designated to further 

mitigate possible environmental impacts. 

In addition, based on the analysis of the EIS and findings in the ROD, environmental monitoring 

programs may be developed and/or stipulated to respond to site-specific conditions. However, 

natural gas operations are monitored by various federal, state and local agencies to ensure that 

environmental safeguards are implemented and maintained. 

3.0 Public’s Role in the Process 

Public involvement and scrutiny are important parts of the scoping and the environmental analysis 

process. A key component of NEPA is the opportunity for the public to actively participate by 

commenting during scoping as well as on the draft EIS. This public involvement is typically 

focused during the scoping process and during the review of the draft EIS. 

4.0 Role of Government Agencies and Private Entities 

The organization and preparation of the EIS document is developed by the lead agency (BLM) 

and is based on legal requirements. EIS responsibilities are characterized by the following 

interrelated entities: 

3⁄4 Lead Agency; 

3⁄4 Cooperating Agency; 

3⁄4 Project Proponent; 

3⁄4 Independent Third Party Contractor; and, 

Seminoe Road Gas Development Project B-7 
Draft Environmental Impact Statement November 2005 

3⁄4 Interested Agencies. 

4.1 Lead Agency 

For the preparation of the Seminoe Road Project EIS, the BLM is the federal lead agency. 

The BLM has several levels of responsibility established in order to fully meet its NEPA 

obligations. The Wyoming State Director of the BLM is the NEPA authorized officer for the project 

and will decide whether of not to allow natural gas development on public lands in the project 

area. The Wyoming State Director is also directly responsible for NEPA compliance regarding the 

scope and content of the EIS. The Director will make decisions to approve or disapprove natural 

gas development on public lands once the EIS is finalized. 

The BLM assigned Mr. David Simons as the EIS project lead to oversee the various aspects of the 

EIS effort including study design, public involvement, review of data collection and analysis, and 

the final content of the EIS. Mr. Simons is serving as the primary liaison among the BLM, the thirdparty contractor, and other agencies and organizations. 

The BLM has selected specialists for the Interdisciplinary (ID) Team for the Seminoe Road EIS. 

The primary responsibilities of the ID Team are to help develop the scope of work, furnish 

guidance to the third-party contractor, and participate in the evaluation and presentation of data 

leading to the final EIS and the Record of Decision. They are also be responsible for working with 

the technical specialists of the third-party contractor, miscellaneous other interested government 

agency personnel, and various other organizations in the area of their expertise. 

4.2 Cooperating Agencies 

The Saratoga-Encampment-Rawlins Conservation District (SERCD) is a cooperating agency with 

the BLM on the Seminoe Road Project EIS. As such, SERCD officials provided input into the EIS 

process and documents. 

4.3 Project Proponent 

Dudley & Associates (Dudley) is the project proponent. 

B-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

During the summer of 2001, Dudley completed construction of the Seminoe Road Pilot Project, 

which consisted of sixteen pilot production wells and one pressure observation well. For this Pilot 

Project, the BLM prepared an environmental analysis for the Seminoe Road Coalbed Methane 

Pilot (Seminoe Road Pilot) Project (WY-030-EA00-288). 

When many of these Pilot Project wells began to show the promise of gas production, Dudley 

pursued and received approval for a gas compressor facility and a gas-gathering pipeline that 

could deliver gas to a commercial gas transmission pipeline. The BLM prepared an environmental 

analysis for the Seminoe Road Coalbed Methane Natural Gas Gathering Pipeline/Access Road 

and Compressor Station/Storage Yard/Access Road (Seminoe Road Pipeline) Project (WY-030­

EA2-229). The construction of these facilities is pending. 

Dudley continued to analyze Pilot Project results, and, in September of 2002, the company 

notified the BLM Rawlins Field Office of its desire to expand drilling, develop coalbed methane 

natural gas wells, and install associated facilities within the firm’s lease holdings in the area. It was 

this notification that triggered the preparation of an EIS. 

As a result of their role as project proponent for the development and operation of coalbed 

methane extraction from their leases in the project area, Dudley has been responsible for 

preparation of project development and operational plans. In addition, Dudley is providing the BLM 

and other appropriate regulatory agencies with environmental information and data required to 

address the environmental impacts of potential development on their leases. 

Dudley is also responsible for funding an independent consulting firm to assemble the EIS and 

related documents. The BLM conducts the assessment and prepares the documents with the 

assistance of a contractor. 

4.4 Independent Third-Party Contractor 

The independent third-party contractor for the Seminoe Road EIS is S. Edwards Inc. (SEI) and 

assists the BLM in the preparation of the EIS. The contractor obtains data, assists in alternative 

development, and documents the analysis leading to the final EIS. An SEI project manager acts 

as the liaison with the BLM. This manager oversees his own group of resource and technical 

specialists who are assisting the BLM in analyzing data, estimating effects, recommending 

mitigation measures, and developing the technical sections of the draft and final EIS documents. 

Seminoe Road Gas Development Project B-9 
Draft Environmental Impact Statement November 2005 

4.5 Interested Agencies 

The BLM has contacted the following federal, state, and local agencies regarding the Seminoe 

Road EIS: 

3⁄4 Environmental Protection Agency; 

3⁄4 U.S. Fish and Wildlife Service; 

3⁄4 U.S. Forest Service; 

3⁄4 U.S. National Park Service; 

3⁄4 U.S. Army Corps of Engineers; 

3⁄4 U.S. Department of Energy – Western Area Power Administration; 

3⁄4 U.S. Bureau of Reclamation; 

3⁄4 Wyoming Department of Environmental Quality – Air Quality Division; 

3⁄4 Wyoming Department of Environmental Quality – Water Quality Division; 

3⁄4 Wyoming Department of Environmental Quality – Land Quality Division; 

3⁄4 Wyoming State Engineer’s Office; 

3⁄4 Wyoming Game & Fish Department; 

3⁄4 Wyoming Department of State Parks & Cultural Resources; 

3⁄4 Wyoming State Historical Preservation Office; 

3⁄4 City of Rawlins; and, 

3⁄4 Carbon County. 

The participation of these agencies on the EIS is based upon their interest, their legal 

requirements involved with potential future permitting responsibilities, and their expertise. The 

BLM has submitted a draft EIS to these agencies to solicit their comments and to ensure that 

relevant issues are addressed. 

B-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

5.0 EIS Mailing List 

The BLM Rawlins Field Office maintains a NEPA mailing list of agencies, organizations, and 

individuals to whom NEPA notices are mailed. 

Seminoe Road Gas Development Project B-11 
Appendix C 

Great Divide Resource Management 

Plan Analysis 
November 2005 Draft Environmental Impact Statement 

Appendix C – Great Divide Resource Management 

Plan Analysis 

A January 14, 2005 review of the Wyoming Oil & Gas Conservation Commission (WOGCC) 

database for the Rawlins Field Office (RFO) revealed a total of 3,292 wells on state, federal and 

privately held surface in the RFO that are active (this includes dormant wells [43], completed wells 

[2,951], notices of intent to abandon [57], and spuds [241]). The number of spuds are those wells 

where applications to permit drilling (APD) are approved and notice has been received that drilling 

has been initiated, but there is no report yet of the wells being completed or plugged and 

abandoned. The total count of 3,292 wells goes back to the beginning of oil and gas production 

within the RFO in 1911. From the Great Divide Resource Management Plan (RMP) EIS 

(Assumptions for Analysis, Chapter 4, page 220), the number of wells existing at the time the 

RMP draft EIS (USDI-BLM 1987) was 3,671 wells drilled in the planning area on all ownership; 

and, of these, 1,896 wells were dry and abandoned. That left 1,775 wells (3,671 minus 1,896) 

active prior to the RMP. Subtracting this figure from the 3,292 wells currently in the RFO according 

to the WOGCC leaves 1,517 active producing wells since the RMP EIS. See Table C-1, Well 

Status Summary-Rawlins Field Office. 

Table C-1, Well Status Summary – Rawlins Field Office1 

Status Federal Fee or State Total Wells Present 

Plugged & Abandoned 1,355 1,634 2,989 

Dormant Wells 20 23 43 43 

Completed Wells 1,433 1,518 2,951 2,951 

Monitoring Wells 0 0 0 

Notice of Intent to 

Abandon 19 38 57 57 

Spuds 118 123 241 241 

Expired Permits 788 455 1,243 

Permits to Drill 423 232 655 

Permits Issued 4,161 4,023 8,184 

Total 4,151 4,025 8,176 3,292 

Notes: 

1. Information in this table was obtained from WOGCC on January 14, 2005. 

Plugged and abandoned (P&A) wells are well pads that were drilled and at some point 

abandoned. To enter into P&A status, the wells must be plugged, abandoned, reclaimed and 

subsequently inspected and accepted as reclaimed by the BLM. Wells in the status of “notice of 

intent to abandon” (NOIA) fit into two categories: (1) plugged, abandoned, and awaiting final 

reclamation or (2) plugged, abandoned, reclaimed and awaiting acceptance by the BLM or 

Seminoe Road Gas Development Project C-1 
Draft Environment Impact Statement November 2005 

applicable land manager. For the purposes of this analysis, no NOIA wells are considered 

reclaimed. 

Analysis of 26 wells drilled under the Desolation Flats (DFPA) interim drilling program as of 

January 2004 shows that long-term disturbance has averaged 6.3 acres/well. This includes well 

pads and roads. This comes from actual experience from the DFPA. This figure contrasts with the 

simple average of 3.0 acres of long-term disturbance projected from the five natural gas projects 

listed in Table C-2, Long-Term Disturbance Figures for Existing Oil and Gas Development 

NEPA Documents. 

Table C-2, Long-Term Disturbance Figures for Existing Oil and Gas Development NEPA 

Documents 

Project Title 

Wells 

Approved to 

Drill

1 

Wells 

Drilled to 

Date1 

Authorized 

Wells 

Remaining 

Average 

Disturbance Per 

Well

2 

(acres) 

Authorized 

Disturbance 

Remaining 

(acres) 

Sierra Madre 46 38 8 1.95 16 

Continental 

Divide / 

Wamsutter II 

1,200 964 236 2.9 684 

South Baggs 50 15 35 2.03 71 

Desolation Flats3 250 31 219 6.5 1,424 

Atlantic Rim 113 86 27 1.9 52 

Totals 525 NM 2,247 

Notes: 

1. Dormant, completed, notice of intent to abandon, and wells spud combined 

2. Estimate from environmental analysis document. 

3. Desolation Flats at 6.5 acres is considerably larger than the other. This is due to the exploratory nature of the 

play as compared to the other projects. 1.5 miles of new road per well were projected. 

To convert the current number of wells (1,517) to current acres disturbed long-term, the well 

number was multiplied by 6.5 acres disturbed per well. 1,271 wells x 6.5 acres per well = 9,861 

acres of long-term disturbance to date within the RFO under the Great Divide RMP. 

Currently, there are five projects in the RFO where drilling and production activities are authorized 

but not yet completed. These wells and associated disturbances need to be considered before a 

determination of the number of wells remaining under the RFD scenario described in the RMP can 

be made. Simply adding in the acres of disturbance approved would double count wells already 

constructed and listed in the WOGCC database read-out. See Table C-2, Long-Term 

Disturbance Figures for Existing Oil and Gas Development NEPA Documents, for a 

summary of the oil and gas development projects with wells authorized but not completely drilled. 

C-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Table C-2, Long-Term Disturbance Figures for Existing Oil and Gas Development NEPA 

Documents, shows that approximately 525 wells and 2,247 acres of disturbance remain to be 

completed under existing authorizations for these projects. The well count for wells remaining to 

be drilled was taken on January 14, 2005 from the WOGCC on-line database. 

The total disturbance then for existing and authorized (but not yet drilled) wells is 2,247 acres plus 

9,861 acres = 12,107 acres of long-term disturbance either existing or authorized. Reasonably 

foreseeable development for oil and gas activity within the RFO administrative area as described 

in the Great Divide RMP (BLM 1988a) was projected to include 1,440 new wells (16,092 acres of 

long-term disturbance) over a 20-year period (1986-2005). As stated above, 12,107 acres of 

disturbance are either existing or authorized within the RFO. Long-term disturbance acreage 

available for future, as yet unauthorized oil and gas related disturbance within the RFO area would 

be 3,985 acres (16,092 minus 12,107). 

Wells that are drilled but not successful are short-term disturbance that would be completely 

reclaimed following plugging and abandonment. Successful wells would have short-term 

disturbance during construction and drilling, and long-term disturbance over a smaller area during 

the operational phase of their life. 

Seminoe Road Gas Development Project C-3 
Appendix D 

Agency Jurisdictions 

(Permits and Approvals) 
July 2005 Draft Environmental Impact Statement

Contents

1.0 Introduction ................................................................................................. D-1

2.0 Bureau of Land Management Responsibility............................................... D-1

3.0 U.S. Army Corps of Engineers’ Responsibilities ........................................... D-6

4.0 Environmental Protection Agency Responsibilities .................................... D-7

4.1 Clean Water Act................................................................................................D-7

4.2 Clean Air Act .....................................................................................................D-8

5.0 U.S. Fish and Wildlife Service Responsibilities ............................................ D-8

6.0 Bureau of Reclamation Responsibilities ...................................................... D-9

7.0 Advisory Council on Historic Preservation Responsibilities ........................ D-9

8.0 Wyoming Department Of Environmental Quality – Air Quality Division

Responsibilities ............................................................................................ D-9

8.1 Permit to Construct .......................................................................................D-10

8.2 Permit to Operate ..........................................................................................D-10

8.3 Prevention of Significant Deterioration.........................................................D-10

9.0 Wyoming Department Of Environmental Quality –Water Quality Division

Responsibilities .......................................................................................... D-10

10.0 Wyoming State Engineer’s Office Responsibilities.................................... D-11

11.0 Wyoming Department Of State Parks And Cultural Resources – Division Of

State Parks & Historic Sites Responsibilities ............................................. D-12

12.0 Wyoming Department Of Transportation Responsibilities ....................... D-12

13.0 Wyoming Oil And Gas Conservation Commission....................................... D-12

14.0 Saratoga-Encampment-Rawlins Conservation District ............................. D-13

15.0 Carbon County............................................................................................ D-13

Tables 

Table D-1, List of Tentative Permits and Approvals for Wyoming Coalbed Methane

Operations ................................................................................................................D-2

Seminoe Road Gas Development Project D-i 
November 2005 Draft Environmental Impact Statement

Appendix D– Agency Jurisdictions (Permits and Approvals)

1.0 Introduction 

Coalbed natural gas development and operations in Wyoming require a number of federal, state 

and local permits and approvals. See Table D-1, List of Tentative Permits and Approvals for 

Coalbed Methane Operations. 

Preparation of an environmental impact statement (EIS) and the actual permitting processes are 

related but distinctively separate. An EIS is designed to explore alternatives and discuss 

environmental impacts, but the EIS is not a permit nor does an EIS constitute an approval for a 

particular project. See Appendix B, The NEPA Process. 

The permitting or approval processes give individual federal government decision makers the 

authority to grant, conditionally grant, or deny individual permit applications. Permits may be 

granted with requirements and conditions to eliminate and/or mitigate specific adverse impacts 

pursuant to their individual regulations and guidelines. 

2.0 Bureau of Land Management Responsibility 

The Bureau of Land Management (BLM) typically serves as the lead agency in EIS processes 

that assess large-scale coalbed natural gas development and operational activities on the public 

lands that are administered by the BLM. 

In the case of the Seminoe Road Project EIS, the BLM Wyoming State Director is responsible to 

ensure that the National Environmental Policy Act (NEPA) is implemented correctly and is the 

responsible official for selecting an alternative, defining mitigation measures, outlining any 

monitoring tasks and issuing the Record of Decision (ROD) for any development and operation. 

Prior to the start of any drilling activities on BLM-administered lands, an applicant must submit to 

the BLM site-specific plans for the drilling, testing, completing and equipping process including 

but not limited to location surveys showing the area to be disturbed for access roads, drill pads, 

topsoil piles, pits, drilling and related down hole procedures (including safety plans) and any other 

information the applicant or the BLM deems relevant to the process. 

Seminoe Road Gas Development Project D-1 
Draft Environmental Impact Statement November 2005

Table D-1, List of Tentative Permits and Approvals for Wyoming Coalbed Methane 

Operations 

Agency Permit, Approval, or Action Authority 

Federal Government 

Bureau of Land Management (BLM) 

Permit to drill, deepen, or plug back 

on BLM-managed land (APD process) 

Mineral Leasing Act of 1920, as 

amended (30 U.S.C. 181 et seq.); 

Requirements for Operating Rights 

Owners and Operators, as amended 

(43 C.F.R. 3162) 

ROW grants and temporary use 

permits for pipelines on BLMmanaged land 

Mineral Leasing Act of 1920, as 

amended (30 U.S.C. 185); Onshore 

Oil and Gas Unit Agreements: 

Unproven Areas, as amended (43 

C.F.R. 3180) 

ROW grants for access roads on 

BLM-managed land 

Federal Land Policy and 

Management Act (43 U.S.C. 1761­

1771); Right-of-Way, Principles and 

Procedures, as amended (43 C.F.R. 

2800) 

Authorization for flaring and venting of 

natural gas on BLM-managed land 

Mineral Leasing Act of 1920, as 

amended (30 U.S.C. 181 et seq.); 

Requirements for Operating Rights 

Owners and Operators, as amended 

(43 C.F.R. 3162) 

Plugging and abandonment of a well 

on BLM-managed land 

Mineral Leasing Act of 1920, as 

amended (30 U.S.C. 181 et seq.); 

Requirements for Operating Rights 

Owners and Operators, as amended 

(43 C.F.R. 3162) 

Bureau of Land Management (BLM) 

(Continued) 

Antiquities and cultural resource 

permits on BLM-managed land 

Antiquities Act of 1906, as amended 

(16 U.S.C. 431-433); Archaeological 

Resources Protection Act of 1979, 

as amended (16 U.S.C. Sections 

470aa-47011); Preservation of 

American Antiquities, as amended 

(43 C.F.R.3) 

Approval to dispose of produced water 

on BLM-managed land 

Mineral Leasing Act of 1920, as 

amended (30 U.S.C. 181 et seq.); 

Special Provisions, as amended (43 

C.F.R. 3164); Onshore Oil and Gas 

Order No. 7, as amended (58 Fed. 

Reg. 47,354) 

U.S. Army Corps of Engineers 

Section 404 permits and coordination 

regarding placement of dredged or fill 

material in area waters and adjacent 

wetlands 

Sections 404 of the Clean Water Act 

of 1972, as amended (33 U.S.C. 

1344); Section 404(b)(1) Guidelines 

for Specification so f Disposal Sites 

for Dredged or Filled Material, as 

amended (40 C.F.R. 230) 

U.S. Bureau of Reclamation Right-of-use authorization Regulations @43 CFR 429 

U.S. Fish and Wildlife Service 

(USFWS) 

Coordination, consultation and impact 

review on federally listed threatened 

and endangered (T&E) species 

Fish and Wildlife Coordination Act 

(16 U.S.C. 661-666c); Section 7 of 

the Endangered Species Act of 

1973, as amended (16 U.S.C. 1536); 

Bald Eagle Protection Act (16 U.S.C. 

668-668dd) 

Migratory bird impact coordination Migratory Bird Treaty Act (16 U.S.C. 

704) 

D-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Agency Permit, Approval, or Action Authority 

U.S. Department of Transportation Control pipeline maintenance and 

operation 

Transportation of Natural and Other 

Gas by Pipeline, Annual Reports, 

Incident Reports, and Safety Related 

Condition Reports, as amended (49 

C.F.R. 191); and Transportation of 

Natural and Other Gas by Pipeline: 

Minimum Safety Standards, as 

amended (49 C.F.R. 192) 

State Government 

Wyoming Department of 

Environmental Quality – Water 

Quality Division 

Permits to construct settling ponds 

and waste water systems, including 

groundwater injection and disposal 

wells 

Wyoming Environmental Quality Act, 

Article 3, Water Quality, as amended 

(W.S. 35-11-301 through 35-11-311) 

Wyoming Department of 

Environmental Quality – Water 

Quality Division (Continued) 

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) 

NPDES permits for discharging 

produced water and storm water 

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): 

EPA-administered Permit Programs: 

NPDES, as amended (40 C.F.R. 

122); State Program Requirements 

(40 C.F.R. 123): EPA Water 

Program Procedures for Decisionmaking, as amended (40 C.F.R. 

124) 

Administrative approval for discharge 

of hydrostatic test water 

Wyoming Environment Quality Act, 

Article 3, Water Quality, as amended 

(W.S. 35-11-301 through 35-11-311) 

Wyoming Department of 

Environmental Quality – Air Quality 

Division 

Permits to construct and permits to 

operate 

Clean Air Act, as amended (42 

U.S.C. 7401 et seq.); Wyoming 

Environmental Quality Act, Article 2, 

Air Quality, as amended (W.S. 35­

11-201 through 35-11-212) 

Wyoming Department of 

Environmental Quality – Land 

Quality Division 

Mine permits, impoundments, and drill 

hole plugging on state lands 

Wyoming Environmental Quality Act, 

Article 4, Land Quality, as amended 

(W.S. 35-11-401 through 35-11-437) 

Wyoming Department of 

Environmental Quality – Solid Waste 

Division 

Construction fill permits and industrial 

waste facility permits for solid waste 

disposal during construction and 

operations 

Wyoming Environmental Quality Act, 

Article 5, Solid Waste Management, 

as amended (W.S. 35-11-501 

through 35-11-520) 

Wyoming Department of 

Transportation 

Permits for oversize, over length, and 

overweight loads 

Chapters 17 and 20 of the Wyoming 

Highway Department Rules and 

Regulations 

Access permits to state highways Chapter 13 of the Wyoming Highway 

Department Rules and Regulations 

Wyoming Oil and Gas Conservation 

Commission / Wyoming Board of 

Land Commissioners / Land and 

Farm Loan Office 

Approval of oil and gas leases, ROWs 

for long-term or permanent off-lease / 

off-unit roads and pipelines, temporary 

use permits, and developments on 

state lands 

Public Utilities, W.S. 37-1-101 et 

seq. 

Seminoe Road Gas Development Project D-3 
Draft Environmental Impact Statement November 2005

Agency Permit, Approval, or Action Authority 

WOGCC 

Permit to drill, deepen, or plug back 

(APD process) 

WOGCC Regulations, Chapter 3, 

Operational and Drilling Rules, 

Section 2 Location of Wells 

Permit to use earthen pit (reserve pits) 

WOGCC Regulations, Chapter 4, 

Environmental Rules, including 

Underground Injection Control 

Program Rules for Enhanced 

Recovery and Disposal Projects, 

Section 1, Pollution and Surface 

Damage (Forms 14A and 14B) 

Authorization for flaring or venting of 

gas 

WOGCC Regulations, Chapter 3, 

Operational and Drilling Rules, 

Section 45 Authorization for Flaring 

or Venting of Gas 

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, State-administered 

program – Class II Wells, as 

amended (40 C.F.R. 147.2551) 

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) 

Change in depletion plans Wyoming Oil and Gas Act, as 

amended (W.S. 30-5-110) 

Wyoming State Engineer’s Office Permits to appropriate ground water 

(use, storage, wells, dewatering) 

W.S. 41-3-901 through 41-3-938, as 

amended (Form U.W. 5) 

Wyoming State Historic Preservation 

Office 

Cultural resource protection, 

programmatic agreements, 

consultation 

Section 106 of National Historic 

Preservation Act of 1966, as 

amended (16 U.S.C. 470 et seq.) 

and Advisory Council Regulations on 

Protection of Historic and Cultural 

Properties, as amended (36 C.F.R. 

800) 

Local Government 

Carbon County 

Construction/use permits County Code and Zoning Resolution 

Conditional use permits County Code and Zoning Resolution 

Road use agreements/oversize trip 

permits County code 

County and crossing/access permits County Code/Engineering 

Department 

Small wastewater permits County Health Department 

Hazardous material recordation and 

storage County Code 

Zone changes Zoning Resolution 

Filing fees County Code 

Noxious weed control County Code 

D-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

The proposed development sites must be staked in the field and inspected by the BLM to ensure 

consistency with the application and that the environmental resources are evaluated in such a 

way that the proposed operations comply with the Resource Management Plan for the specific 

drilling area, as well as any site-specific EIS decisions made for the project. 

Two procedural options are available to the applicant for securing approval to drill: 

3⁄4 A Notice of Staking (NOS) 

3⁄4 An Application for Permit to Drill or Re-enter (APD) 

The NOS system, properly coordinated at the beginning of the action, may expedite final permit 

approval; however, the APD system is the most familiar to oil and gas operators and often 

requires less coordination effort at the start. The choice of which option to use is the decision of 

the applicant. 

Access roads and pipelines located on federal surface outside the leasehold or the unitized area 

require a right-of-way (ROW) for BLM-administered lands. The NOS or APD for BLM land will be 

accepted as a ROW application for these off-lease facilities and the application should detail the 

entire development proposal. 

At the NOS or APD on site inspection, the operator will be provided the Form 2800-14 

(ROW/Temporary Use Permit) containing standard items and conditions, ad Form 1323-2 (ROW 

Cost Recovery and Fee Determination Record) for any ROWs involved on BLM-administered 

land. Complete APD applications involving a BLM ROW should include a signed Form 2800-14 

and any required ROW cost recovery fees. APD conditions of approval will also apply to ROW 

portions of the permit. 

The NOS, APD, and ROW applications will be revised as necessary per negotiations with the 

BLM. The BLM may approve or deny site-specific proposals and any such conditions of approval 

will be attached to and become part of each permit. Upon receipt of final BLM approval, the 

operator could commence with proposed activities. 

Seminoe Road Gas Development Project D-5 
Draft Environmental Impact Statement November 2005

3.0 U.S. Army Corps of Engineers’ Responsibilities 

The Corps of Engineers is responsible for issuing permits under Section 404 of the Clean Water 

Act which requires permits for the “discharge of dredged or fill material into navigable waters.” 

Guidelines promulgated by the Environmental Protection Agency (EPA) under Section 404(b)(1) 

generally prohibit the discharge of dredged or fill materials into “Waters of the United States” 

unless it can be shown that the discharge is the least environmentally damaging practicable 

alternative to achieve the basic purpose of the proposed project. 

The term “Waters of the United States” is broadly defined as waters that are or could be used in 

interstate or foreign commerce. In addition to territorial seas and interstate waters, this includes 

other waters such as lakes, mud flats, sloughs, and wetlands, which are or could be used in 

interstate or foreign commerce. To the degree that they impact “Waters of the United States,” 

various activities associated with coalbed methane operations, such as road construction or 

upgrades, well pad site development and construction, staging area construction sites, 

compressor station sites, etc., may require a Section 404 Permit. 

The Corps of Engineers must comply with Executive Orders 11990 and 11998 with respect to 

impacts to the nations wetlands and/or floodplains. The “no net loss” wetlands policy is outlined 

in an agreement between Corps of Engineers and the EPA. The policy goal of the no net loss to 

wetland acreage or function is implemented primarily through permit review. 

Two types of permits apply to wetland fill proposals. These are nationwide permits and individual 

permits. Nationwide permits can be authorized for a number of low-impact actions, but these 

permits carry a number of standard mitigation measures. If the affected area is not isolated 

wetlands or wetlands above the headwaters, or if the proposed activity would affect more than 0.5 

acres of jurisdictional wetlands, an individual permit is required. 

In reviewing Section 404 permit applications, the Corps of Engineers must evaluate whether the 

benefits from the project outweigh the predicted environmental impacts. This is called a “public 

interest review.” Factors considered during the public interest review include the following: 

3⁄4 Basic project purpose and need;


3⁄4 Water dependency; 


D-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

3⁄4 Availability of practicable alternatives, taking into consideration cost, logistics, and 

technology; and, 

3⁄4 Environmental impacts. 

The Corps of Engineers evaluate whether the proposal is the least environmentally damaging 

practicable alternative. It may be necessary to include mitigation measures that will reduce 

impacts to the aquatic environment to an acceptable level. These measures may include 

avoiding fills to reducing the area of fill, creating or restoring aquatic environments, and/or 

enhancing the value of an existing aquatic area. 

4.0 Environmental Protection Agency Responsibilities 

NEPA documents, such as the Seminoe Road Project draft EIS, the final EIS, and the ROD 

completed by the BLM will be filed with the Environmental Protection Agency (EPA). 

In addition to its NEPA oversight responsibilities, the EPA has responsibilities involved with the 

following: 

3⁄4 Clean Water Act; and 


3⁄4 Clean Air Act.


4.1 Clean Water Act 

The Clean Water Act has established the following surface water programs, which may concern 

coalbed natural gas operations: 

3⁄4 The NPDES permit program regulating the point source and storm water discharge of 

pollutants, including sediment; 

3⁄4 The Section 404 permit program regulating the discharge of dredged or fill material; and, 

3⁄4 The Section 311 program regulating spills of oil and hazardous substances. 

EPA established the National Pollutant Discharge Elimination System (NPDES) program for 

regulating surface water quality. The Federal Water Pollution Control Act Amendments of 1972 

and supplement amendments and re-authorization principally established this program. In its 

amended and re-authorized form, this statute as a whole is now generally referred to as the 

Clean Water Act. 

Seminoe Road Gas Development Project D-7 
Draft Environmental Impact Statement November 2005

Section 402 of the Clean Water Act establishes the NPDES permit program. The Wyoming 

Department of Environmental Quality is the permitting authority in the state of Wyoming for the 

issuance of NPDES permits pursuant to Section 402 of the Clean Water Act. 

Section 404 of the Clean Water Act authorizes the Corps of Engineers to issue permits “for the 

discharge of dredged or fill materials into navigable waters.” These permits are addressed under 

14.2, U.S. Army Corps of Engineers Responsibilities. The EPA is responsible for reviewing the 

consistency of any proposed 404 action with Section 404(b)(1) guidelines. 

Section 311 of the Clean Water Act establishes requirements relating to discharges or spills of oil 

or hazardous substances. Discharges or spills of oil in “harmful quantities” are prohibited. The 

EPA has established a requirement for the preparation of a spill prevention control and 

countermeasure (SPCC) plan by facilities that handle substantial quantities of oil. 

4.2 Clean Air Act 

In addition to water quality oversight, the EPA also maintains control over the air resources as 

outlined in the Clean Air Act. The Clean Air Act’s most basic goals are to protect public health 

and welfare. The EPA can comment on, but is not responsible for, a new source (air quality) 

construction permit issued by the Wyoming Department of Environmental Quality. 

5.0 U.S. Fish and Wildlife Service Responsibilities 

The U.S. Fish and Wildlife Service administers the Endangered Species Act, as re-enacted in 

1982, and the Bald Eagle Protection Act of 1940, as amended. 

On coalbed methane projects, the BLM must consult with the U.S. Fish and Wildlife Service 

regarding any federally listed threatened or endangered species that might be impacted by 

proposed operations. This is known as the Section 7 Consultation. 

If needed, a biological assessment will be prepared by the BLM for any federally listed threatened 

or endangered species, and this document will be submitted to the U.S. Fish and Wildlife Service. 

If adverse impacts to threatened or endangered species are projected, specific design measures 

to protect the affected species may need to be developed. 

D-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

6.0 Bureau of Reclamation Responsibilities 

The U.S. Bureau of Reclamation manages dams, hydro-electric power stations, canals and 

reservoirs in seventeen western states, including Wyoming. These include the Seminoe, Kortes 

and Pathfinder dams on the North Platte River. See Appendix E, Regional Activity. 

In compliance with 43 CFR 429, government agencies, corporations and the public may submit 

an application for right-of-use authorization to use Bureau of Reclamation Lands or the surfaces 

of any project body of water. Consideration of Applications to use Bureau of Reclamation project 

lands and water surfaces is completely discretionary, and the Bureau of Reclamation reserves 

the right to refuse authorization of any use which may be incompatible with the federallyauthorized purposes of the Bureau of Reclamation project or interferes with the Bureau’s rights or 

operations. 

7.0 Advisory Council on Historic Preservation Responsibilities 

A copy of both the draft EIS and final EIS documents must be filed with the Advisory Council on 

Historic Preservation. This agency works in an advisory role to assist the BLM with compliance 

with the National Historic Preservation Act and the American Indian Religious Freedom Act. In 

addition, the Wyoming Department of State Parks & Cultural Resources, Wyoming State Historic 

Preservation Office will give concurrence with any agency determined cultural impacts. The 

Advisory Council on Historic Preservation would be available to serve in an advisory role if 

requested by the Wyoming agency. The Advisory Council on Historic Preservation may also 

review state program activities and determine relative compliance to the previously mentioned 

National Historic Preservation Act. 

8.0 Wyoming Department Of Environmental Quality – Air Quality 

Division Responsibilities 

The Wyoming Department of Environmental Quality, Air Quality Division has review and approval 

authority over new source construction or additions or modifications to existing sources for 

releasing contaminants into the air. The Air Quality Division has regulatory responsibility for the 

permits to construct, operate and prevent significant deterioration of air resources. 

Seminoe Road Gas Development Project D-9 
Draft Environmental Impact Statement November 2005

8.1 Permit to Construct 

This permit requires the applicant to submit an emissions inventory listing sources and amounts 

of air pollution released, an analysis of best available control technology, and a demonstration 

that ambient air quality standards, including levels for toxic air pollutants will not be exceeded. 

The statutory authority for new source construction approval is the Wyoming Environmental 

Quality Act, Article 2, Air Quality Act and subsequent regulations. 

8.2 Permit to Operate 

The Wyoming DEQ Air Quality Division has a comprehensive air operating permit program, which 

is consistent with the requirements of Title V of the Federal Clean Air Act. Facilities will be 

required to obtain operating permits within six months of the issuance of construction activities. 

8.3 Prevention of Significant Deterioration 

The basic objective of the prevention of significant deterioration (PSD) air quality program is to 

prevent substantial degradation of air quality in areas that are in compliance with national ambient 

air quality standards, while maintaining a margin for future growth. As part of the new source 

review, PSD applicability is determined. 

Criteria that trigger the requirements for a PSD permit vary depending on the type of facility. 

Pollutants can include both particulate (dust) and gaseous (SO2, CO2, NOx, and HC) emissions. 

Specific information on PSD requirements can be found in 40 CFR 52.221. 

9.0 Wyoming Department Of Environmental Quality – 

Water Quality Division Responsibilities 

Under authority delegated by the EPA, and requirements in the Wyoming Environmental Quality 

Act, Article 3, Water Quality, the Wyoming DEQ, Water Quality Division regulates the discharge 

of pollutants into Wyoming’s surface waters through the NPDES and stormwater runoff permit 

programs. 

An application for an individual NPDES permit requires information on water supply volumes, 

water utilization, waste water flow characteristics and disposal methods, planned improvements, 

D-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

storm water treatment, plant operation, materials and chemicals used, production, and other 

related information. 

Operations for which EPA has not promulgated storm water effluent limits are required to obtain 

coverage under a general storm water permit issued by the Wyoming DEQ, Water Quality 

Division. 

10.0 Wyoming State Engineer’s Office Responsibilities 

The State Engineer’s office considers coalbed natural gas production different than traditional 

natural gas production, given the necessity for water production to allow the release of the gas 

resource. The intentional production (or appropriation) of groundwater for coalbed natural gas 

production lead to the designation of coalbed natural gas as a beneficial use of water and, 

subsequently, to a requirement for a permit to appropriate the groundwater. 

Prior to drilling a well for the purpose of extracting natural gas from coalbeds, a groundwater 

(well) permit must be obtained from the Wyoming State Engineer. The proponent for the coalbed 

natural gas wells will need to file Form U.W.5 with the State Engineer. The beneficial use of this 

water, as stated on the application form, is water produced in the production of coalbed natural 

gas. Unless specified in the well permit, there is no other beneficial use of this produced water 

authorized by the issuance of the well permit. In addition, unless specified in the groundwater 

permit, coalbed natural gas produced water has no other implied use and is considered to be 

unappropriated waters of the State of Wyoming. If the coalbed natural produced water is 

discharged and not used for any other beneficial purposes, the Wyoming State Engineer requires 

no further groundwater permitting. 

If the coalbed natural produced water is used for purposes other than coalbed methane 

production, these uses must be specified in the well application at the time of filing. If the 

produced water is to be stored in an impoundment, surface water reservoir filing procedures must 

be followed unless there are no other beneficial uses of the water and the impoundment is 

located off the channel of a natural water course. Under these specific conditions, the Wyoming 

Oil and Gas Conservation Commission (WOGCC) rules apply. See Section 12.0, Wyoming Oil 

and Gas Conservation Commission. 

Seminoe Road Gas Development Project D-11 
Draft Environmental Impact Statement November 2005

Coalbed natural proponents seeking to store produced water or put produced water to some 

beneficial use should consult the April 26, 2004 revised interim policy memo issued by the 

Wyoming State Engineer’s office detailing permitting requirements for water produced during the 

recovery of coalbed natural. 

11.0 Wyoming Department Of State Parks And Cultural Resources – 

Division Of State Parks & Historic Sites Responsibilities 

The Wyoming State Historic Preservation Office also must be consulted when projects are 

subject to review under Section 106 of the National Historic Preservation Act of 1966. This act 

requires that all federal agencies take into account the effect of their actions on historic 

properties. The Wyoming State Historic Preservation Office should be consulted to determine if 

the site has been surveyed, if there are identified historic resources on site, and if the property is 

listed or eligible for listing on the National Register of Historic Places. If the project will adversely 

affect property that meets the National Historic Register criteria, the Wyoming State Historic 

Preservation Office will recommend ways to avoid or mitigate that adverse affect. Also see 

Appendix M, Cultural Resources Management Plan. 

12.0 Wyoming Department Of Transportation Responsibilities 

The Wyoming Department of Transportation is responsible for compliance with Wyoming state 

requirements for road design and construction. This agency’s responsibilities include review and 

approval of applications for any upgraded road access permits. The Wyoming Department of 

Transportation also monitors traffic loads on highways to ensure that proper maintenance is 

completed and that any future highway expansions to handle traffic are budgeted. 

13.0 Wyoming Oil And Gas Conservation Commission 

The WOGCC has jurisdiction and authority to promote the responsible development of 

Wyoming’s oil and gas natural resources. This agency’s responsibilities include approval of oil 

and gas leases, granting ROWs for long-term or permanent off-lease/off-unit roads, permits to 

drill, deepen or plug back wells (APD process), permits for Class II underground injection wells, 

and eventual well plugging and abandonment. See Table D-1, List of Tentative Permits and 

Approvals for Wyoming Coalbed Methane Operations. 

The WOGCC has overall responsibility for a number of activities, including: 

D-12 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

3⁄4 The efficient exploration, development, production, and conservation of Wyoming’s oil 

and natural gas resources; 

3⁄4 The protection of public health, safety and welfare, the environment, and mineral owners 

correlative rights; 

3⁄4 The coordination with and maintenance of working relationships with those having an 

interest in Wyoming’s oil and natural gas resources; and, 

3⁄4 The responsibility to provide information to support oil and natural gas decision-making 

activities within the State of Wyoming. 

The WOGCC maintains a staff to implement its permitting, approval, oversight, and informational 

mandates. 

14.0 Saratoga-Encampment-Rawlins Conservation District 

The Saratoga-Encampment-Rawlins Conservation District (SERCD) is serving as an EPA 

cooperating agency with the BLM on the Seminoe Road Project EIS 

The SERCD is a member of the Wyoming Association of Conservation Districts whose mission 

incorporates the following principles: 

3⁄4 Conservation of soil and water resources;


3⁄4 Control of soil erosion; 


3⁄4 Protection of water quality;


3⁄4 Reduction of siltation of stream channels and reservoirs;


3⁄4 Wise use of water and all other natural resources; 


3⁄4 Preservation and enhancement of wildlife habitat; 


3⁄4 Protection of tax base; and,


3⁄4 Promotion of the health, safety and general welfare of citizens through a responsible


conservation ethic. 

15.0 Carbon County 

Carbon County has zoning requirements, which are overseen by the Carbon County Planning 

Department and County Commissioners. No special use permit is required for this project. 

Seminoe Road Gas Development Project D-13 
Draft Environmental Impact Statement November 2005

Carbon County does require permits to construct permanent buildings. The applications for 

building permits require detailed plans for structures including electrical plans, plumbing plans, 

floor layout, sewage facilities, drainage plans, size and shape of the buildings, access, size and 

shape of the foundation walls, beams, air vents, window access, and heating and cooling 

mechanical aspects. Permits are issued upon approval of the plans. The county may inspect the 

buildings during construction. 

D-14 Seminoe Road Gas Development Project 
Appendix E 

Regional Activity 
November 2005 Draft Environmental Impact Statement 

Contents

1.0 Introduction......................................................................................................................E-1


2.0 Oil and Gas Activities ......................................................................................................E-1


3.0 Oil Refining.......................................................................................................................E-1


4.0 Oil and Gas Pipelines ......................................................................................................E-1


4.1 Conoco Pipeline .............................................................................................................E-1


4.2 Proposed Natural Gas Transmission Pipeline................................................................E-4


5.0 Mining Activities ..............................................................................................................E-4


5.1 Shoshone Mine ..............................................................................................................E-4


5.2 Seminoe I and II Mines...................................................................................................E-4


5.3 Medicine Bow Mine ........................................................................................................E-4


6.0 Union Pacific Railroad.....................................................................................................E-5


7.0 Highways ..........................................................................................................................E-5


8.0 Dams .................................................................................................................................E-5


9.0 Hydro-Electric Generating Power Stations ...................................................................E-6


9.1 Seminoe Power Station..................................................................................................E-6


9.2 Kortes Power Station......................................................................................................E-7


10.0 Electric Transmission Lines ...........................................................................................E-7


11.0 Reservoirs ........................................................................................................................E-7


11.1 Seminoe Reservoir .....................................................................................................E-7


11.2 Pathfinder Reservoir...................................................................................................E-8


12.0 Recreation ........................................................................................................................E-8


12.1 Seminoe State Park....................................................................................................E-8


12.2 North Platte River .......................................................................................................E-8


12.3 Miracle Mile.................................................................................................................E-9


12.4 Seminoe-Alcova Backcountry Byway .........................................................................E-9


13.0 Wilderness Areas.............................................................................................................E-9


13.1 Mount Zirkel Wilderness .............................................................................................E-9


13.2 Savage Run Wilderness ...........................................................................................E-10


13.3 Platte River Wilderness ............................................................................................E-10


13.4 Huston Park Wilderness ...........................................................................................E-10


13.5 Encampment River Wilderness ................................................................................E-10


14.0 Wilderness Study Areas................................................................................................E-11


14.1 Adobe Town..............................................................................................................E-11


14.2 Encampment River Canyon......................................................................................E-11


14.3 Ferris Mountains .......................................................................................................E-11


14.4 Prospect Mountain....................................................................................................E-11


14.5 Bennett Mountains....................................................................................................E-12


15.0 Agricultural Activities....................................................................................................E-12


16.0 Housing Development...................................................................................................E-12


17.0 Historic Sites ..................................................................................................................E-12


18.0 Other Potential Projects ................................................................................................E-13


Seminoe Road Gas Development Project E-i 
Draft Environmental Impact Statement November 2005 

Tables

Table E-1, Projects Analyzed Under NEPA in Southern Wyoming ..............................................E-2


Table E-2, Dam Statistics .............................................................................................................E-6


Figures 

Figure 19, Regional Activity 

Figure 20, Air Quality Modeling Domain 

E-ii Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Appendix E – Regional Activity

1.0 Introduction 

A number of activities have, are, or will occur in the areas within and adjacent to the Seminoe 

Road Project. These activities involve oil and gas activities, coal mining, power generation from 

hydro-electric generating power stations, electric transmission, recreation, and agricultural 

activities. See Figure 19, Regional Activity. 

2.0 Oil and Gas Activities 

Oil and gas production, development and exploration continue in Wyoming. A listing of oil and gas 

projects previously and currently under review by the BLM in southern Wyoming are set forth in 

Table E-1, Projects Analyzed Under NEPA in Southern Wyoming. 

3.0 Oil Refining 

The Sinclair Oil Refinery is located in Sinclair, Wyoming. The Sinclair Oil Corporation purchased 

the refinery from Pasco Corporation in 1976. The refinery is capable of processing approximately 

54,000 barrels of crude oil per day into fuels and asphalt. 

4.0 Oil and Gas Pipelines 

Two major pipelines presently exist in the area within and adjacent to the Seminoe Road Project. 

Another major new natural gas transmission pipeline that would parallel I-80 across southern 

Wyoming is under consideration. 

4.1 Conoco Pipeline 

Conoco Oil and Refining Company owns and operates a refined oil pipeline which traverses 

through the Seminoe Road Project. This pipeline is part of the Seminoe pipeline system which 

connects refineries in Billings, Montana and Sinclair, Wyoming (about 335 miles). 

Seminoe Road Gas Development Project E-1 
Table E-1, Projects Analyzed Under NEPA in Southern Wyoming 

Project 

Date 

ROD/DR 

Signed 

Number of 

Wells Existing 

When EIS/EA 

Was Written 

Number of 

Wells 

Allowed by 

ROD/DR 

Number of 

Wells Drilled 

Since 

ROD/DR2 

Dry Hole, 

Depleted or 

Plugged & 

Abandoned2 

Completed 

but not 

Production(2) 

Producin

Wells 

Riley Ridge 1/25/84 10 238 19 5 1 23 Burley 6/7/94 15 32 19 3 0 31 Jonah II Field 4/27/98 88 450 41 0 0 129 Coordinated Activity Plan Area 8/16/91 1,080 500 409 354 0 1,135 Soda Unit 4/12/89 4 17 0 1 0 3 Castle Creek 10/24/83 2 16 6 0 0 8 Moxa Arch 3/7/97 849 1,325 163 62 0 947 Hickey Mountain 5/13/87 16 70 19 9 10 26 Road Hollow 9/83 1 9 8 5 0 4 Fontenelle 8/16/96 907 1,292 151 6 6 1,052 Stagecoach 9/27/95 5 72 8 1 9 9 East LaBarge 5/29/92 83 28 19 1 83 19 Bird Canyon 6/25/93 6 14 6 0 6 6 Essex Mountain 8/4/95 0 3 0 0 0 0 Bravo Unit 7/20/95 3 10 6 1 3 7 Mulligan Draw 9/23/92 11 40 12 3 11 17 Creston Blue Gap 10/4/94 202 200 100 3 7 234 Dripping Rock/Cedar Break 4/3/85 11 58 20 2 11 24 Sierra Madre 9/21/87 16 46 27 2 16 30 Hay Reservoir 6/24/92 36 26 20 2 20 40 Jack Morrow Hills Pending 66 1104 NA 14 20 46 Continental Divide/Greater Wamsutter 

7/20/95 845 3,0004 277 13 0 328 

Pinedale Anticline 7/27/2000 41 7003 105 1 0 85 South Baggs Pending 17 904 NA 13 1 16 Upper Green River – USFS MA 72 Pending 23 174 NA 23 0 0 Hoback Basin – USFS MA 21 Pending 8 874 NA 8 0 0 Bitter Creek Shallow Gas Project Area 

Pending 14 NA NA 64 6 14 

Pacific Rim Shallow Gas Pending 0 150 NA 0 0 0 
November 2005 Draft Environmental Impact Statement 

Project 

Date 

ROD/DR 

Signed 

Number of 

Wells Existing 

When EIS/EA 

Was Written 

Number of 

Wells 

Allowed by 

ROD/DR 

Number of 

Wells Drilled 

Since 

ROD/DR2 

Dry Hole, 

Depleted or 

Plugged & 

Abandoned2 

Completed 

but not 

Production(2) 

Producin

Wells 

Copper Ridge Pending 0 89 NA 0 0 0 Vermillion Basin 8/15/02 0 56 NA 0 0 0 Jonah Infill Pending 0 1,250 NA 0 0 0 Desolation Flats Peding 0 385 NA 0 0 0 South Piney Pending 0 210 NA 0 0 0 Lower Bush Creek Pending 0 22 0 0 0 Seminoe Road Pending 1,240 Atlantic Rim 

Pending 

7/26/02 6/26/02 

2,000 

Wolverine/Shell 3 2 Little Monument Pending 31 31? 

Total 4,359 13,886 1,053 

Notes: 

1. Reasonably foreseeable development that could take place within the next 10 to 15 years within southwestern Wyoming 2. As of 12/98 3. 700 pads – not wells 4. No ROD available – pending completion of EISs and EAs 

Seminoe Road Gas Development Project E-5 
Draft Environmental Impact Statement November 2005 

4.2 Proposed Natural Gas Transmission Pipeline 

The construction and operation of another major natural gas transmission pipeline that would 

essentially parallel to I-80 from Rock Springs to Cheyenne, Wyoming is under consideration. 

5.0 Mining Activities 

Coal mining has and continues to occur within and surrounding the Seminoe Road Project area. 

5.1 Shoshone Mine 

The Shoshone Mine is located approximately 4 miles north of Hanna, Wyoming, and was 

operated until 2001 as both a surface and an underground coal mine. Final reclamation activities, 

including the removal of surface facilities and the coal loadout, were completed in 2002. 

Reclamation is currently being monitored by officials from the Wyoming Department of 

Environmental Quality (DEQ), Land Quality Division. Such monitoring will continue for up to 10 

years, as required by Wyoming DEQ regulations, to ensure that revegetation has met permit 

specifications. 

5.2 Seminoe I and II Mines 

The Seminoe I Mine was operated as a surface coal mine. This operation is now closed and has 

been reclaimed. 

The Seminoe II Mine, which is approximately 6 miles northeast of Hanna, Wyoming, has been 

operating since 1973. This mine is owned and operated by Arch Coal, Inc. The mine is permitted 

by the Wyoming DEQ, Land Quality Division, to produce 2 million tons of coal per year, but, in 

recent years, this mine has produced less than 300,000 tons of coal per year. The Seminoe II 

Mine is reported to have additional coal resources; however, the mine is now in temporary 

cessation. Future economics will determine if these resources are economically minable. 

5.3 Medicine Bow Mine 

The Medicine Bow Mine is a surface coal mine with a production capability of approximately 2 

million tons of coal per year. This mine is owned and operated by Arch Coal, Inc. and is located 

E-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

approximately 6 miles west of Hanna, Wyoming, on U.S. Highway 30. Historical production at the 

mine has reached 1.8 million tons of coal per year; however, 2003 production was less than 

400,000 tons per year. The mine is now in temporary cessation. Future economics will determine 

if production is to resume. 

6.0 Union Pacific Railroad 

The main routing of the Union Pacific Railroad is located south of the Seminoe Road Project. This 

rail line roughly parallels Interstate 80. Rail spurs have been constructed near the Town of Hanna 

to serve the coal mines in the area. See Section 5.0, Mining Activities. 

7.0 Highways 

Interstate 80 is a federal four-lane interstate highway, which transects southern Wyoming. This 

major interstate highway experiences about 12,000 trucks per day of freight movement from the 

west coast to Midwest markets. 

Seminoe Road (County Road 351) is a two-lane asphalt road that basically bisects the Seminoe 

Road EIS analysis area. This highway was recently upgraded from the Town of Sinclair to 

Seminoe State Park. The upgrade work included widening and paving of the road and was 

completed in early 2003. Refer to Section 3.12, Transportation for a description of all other roads 

within and adjacent to the Seminoe Road Project. 

8.0 Dams 

The Bureau of Reclamation operates the following three dams on the North Platte River north of 

the Seminoe Road Project: 

3⁄4 Seminoe Dam 

3⁄4 Kortes Dam 

3⁄4 Pathfinder Dam 

Details about these facilities are set forth in Table E-2, Dam Statistics. 

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Draft Environmental Impact Statement November 2005 

Table E-2, Dam Statistics 

Seminoe Dam Kortes Dam Pathfinder Dam 

County in Wyoming Carbon Carbon Natrona 

Location 

31 miles northeast of 

Rawlins 

60 miles southwest of 

Casper 

47 miles southwest of 

Casper 

Dam Type 

Concrete Medium-Thick 

Arch Concrete Gravity 

Cyclopean Masonry 

Arch Gravity 

Watercourse North Platte River North Platte River North Platte River 

Reservoir Seminoe Kortes Pathfinder 

Original Construction 1936-1939 1946-1951 

1905-1909 

(Modified 1910-12; 

1915; 1919-22; 1931; 

1949-50; 1958-61; 

1996-97) 

National ID Number WY01297 WY01294 WY01296 

Drainage Area 

(square miles) 7,210 0 14,600 

Total Storage 

(acre-feet) 

1,017,279 @ 

Elevation 7,358 ft 

4,739 @ 

Elevation 6,142 ft 

1,016,500 @ 

Elevation 5,858.1 ft 

Outlet Works (cfs) 3,000 @ Elevation 

6,357 ft NA 3,000 @ Elevation 5,858.1 ft 

Crest Elevation (ft) 6,361 6,169 5,858.1 

Structural Height (ft) 295 244 214 

Hydraulic Height (ft) 206 200 192 

Crest Length (ft) 530 440 432 

Crest Width (ft) 15 24 10.9 

Base Width (ft) 85 193 96.5 

Volume of Concrete 

(cubic yards) 210,000 147,000 65,700 

Power Plant Yes Yes No 

Service Date August 1939 June 1950 -

Capacity (kW) 51,750 36,000 -

9.0 Hydro-Electric Generating Power Stations 

Electric power is generated from two hydro power plants on the North Platte River north of the 

Seminoe Road Project. 

9.1 Seminoe Power Station 

The Seminoe Power Station is located at the Seminoe Dam and is operated by the U.S. Bureau of 

Reclamation. The power plant is located at the base of the Seminoe Dam and has a rated head of 

166 feet. The plant contains three units, each composed of a 1,015-kilowatt generator driven by a 

20,800 horsepower turbine. The Seminoe Dam and associated power plant were constructed 

E-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

between 1936 and 1939. The original capacity of the plant was 32,400 kilowatts; however, the 

plant was upgraded in the mid 1970s to its current installed capacity of 45,000 kilowatts. 

9.2 Kortes Power Station 

The Kortes Power Station is located at Kortes Dam, downstream of the Seminoe Dam. This 

electric power generating facility is also operated by the U.S. Bureau of Reclamation. Power 

generation from the Kortes Power Plant is coordinated with that from the Seminoe Power Plant. 

The reinforced concrete power house at the Kortes Power Plant occupies the entire width of the 

Platte River Canyon at the toe of the Kortes Dam. This plant has three 18,500 horsepower 

turbines and three 12,000-kilowatt generators with a combined capacity of 36,000 kilowatts. The 

Kortes Power Plant is used as a peaking plant except when lower water years restrict outflow. The 

power plant was originally constructed in 1941. Unit 2 was reworked in 1973; Units 1 and 3 were 

reworked in 1985. 

10.0 Electric Transmission Lines 

Western Area Power Administration (WAPA or Western) owns and operates a series of 115 kV 

electric transmission lines that originate from the Kortes and Seminoe hydro power stations. One 

of these 115 kV transmission lines crosses the Seminoe Road EIS analysis area. 

11.0 Reservoirs 

Two large reservoirs are located within and north of the Seminoe Road Project area. They are the 

Seminoe Reservoir and the Pathfinder Reservoir. 

11.1 Seminoe Reservoir 

The Seminoe Reservoir is approximately 20 miles north of the Town of Sinclair and can be 

accessed via Carbon County Road 351. The reservoir encompasses an estimated 20,300 acres 

and offers recreational opportunities such as boating, fishing, water skiing, and wildlife and 

waterfowl observation. The predominate fish species caught in the reservoir are trout and walleye. 

Seminoe Road Gas Development Project E-7 
Draft Environmental Impact Statement November 2005 

11.2 Pathfinder Reservoir 

The Pathfinder Reservoir is located on the North Platte River approximately 10 miles north of the 

Seminoe Reservoir. This reservoir encompasses an area of approximately 26,600 acres. Only 80 

of these acres have been developed for public use. All 117 miles of shoreline are available for 

recreation, including primitive campsites. Water in the Pathfinder Reservoir is used for drinking 

and irrigation needs. The predominate fish species caught in the reservoir include brown trout, 

cutthroat trout, rainbow trout, and walleye. 

12.0 Recreation 

Recreational areas and opportunities within and adjacent to the Seminoe Road EIS analysis area 

include boating, fishing, camping, hiking, hunting, four wheeling, picnicking, horseback riding, and 

general sight seeing. 

No developed recreation facilities are operated by the BLM or private interests within the 

boundaries of the Seminoe Road EIS analysis area; however, the project area does cover the 

southern end of the Seminoe Reservoir. This reservoir provides boating and fishing opportunities 

with public access to the reservoir at Seminoe State Park. North of Kortes Dam is a 5-mile stretch 

of the North Platte River, which is accessed by fisher people along the riverbanks; this stretch of 

river is known as the “Miracle Mile,” which is a world class fishery. The Miracle Mile is located 

approximately 10 miles north of the northern boundary of the Seminoe Road EIS analysis area. 

12.1 Seminoe State Park 

Seminoe State Park encompasses the northern half of the Seminoe Reservoir. The southern 

boundary of the State Park coincides with the northern boundary of the Seminoe Road EIS 

analysis area. Numerous campsites, picnic areas and boat launching facilities are located within 

the Seminoe State Park. 

12.2 North Platte River 

The North Platte River originates within the Mount Zirkel Wilderness Area in northern Colorado, 

passes through the Seminoe Road EIS analysis area, and flows through southeastern Wyoming 

into Nebraska, where it eventually joins the Missouri River. 

E-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

Three dams have been constructed on the North Platte River north of the Seminoe Road Project 

area. See Section 8.0, Dams. 

12.3 Miracle Mile 

The North Platte River is renowned for its trout fishing, in particular, a 5-mile stretch of the river 

located below Kortes Dam. This stretch of the river is referred to as the “Miracle Mile.” The Miracle 

Mile is a year-round fishery that can be productive during any month of the year, although it may 

be difficult to access this stretch of the river during winter months. Brown, rainbow and cutthroat 

trout are prevalent in the Miracle Mile. 

12.4 Seminoe-Alcova Backcountry Byway 

The BLM has designated a 64-mile stretch of County Road 351 between Sinclair and Alcova, 

Wyoming as a scenic backcountry byway. 

13.0 Wilderness Areas 

No wilderness areas are located within or immediately adjacent to the Seminoe Road Project 

area. Wilderness areas in the broader general region include: 

3⁄4 Mount Zirkel Wilderness Area 

3⁄4 Savage Run Wilderness Area 

3⁄4 Platte River Wilderness Area 

3⁄4 Huston Park Wilderness Area 

3⁄4 Encampment River Wilderness Area 

Wilderness areas are shown on Figure 20, Air Quality Modeling Domain, and are briefly 

described in the following sections. 

13.1 Mount Zirkel Wilderness 

Mount Zirkel Wilderness is located in northern Colorado in the Routt National Forest and 

encompasses approximately 160,000 acres. Elevations within this wilderness range from 7,000 

Seminoe Road Gas Development Project E-9 
Draft Environmental Impact Statement November 2005 

feet to 12,180 feet at the top of Mount Zirkel. The wilderness is accessible from U.S. Highway 40 

and Colorado State Highway 15 and numerous Forest Service roads, mainly Forest Service 

Roads 129 and 60. There are an estimated 150 miles of hiking trails within Mount Zirkel 

Wilderness. 

13.2 Savage Run Wilderness 

Savage Run Wilderness is located in southeast Wyoming in the Medicine Bow National Forest 

and encompasses approximately 14,900 acres. Elevations in this wilderness range from 8,000 to 

10,000 feet. The Savage Run Wilderness is accessed by Wyoming State Highway 230 and 

various Forest Service roads. 

13.3 Platte River Wilderness 

Platte River Wilderness is located in southeast Wyoming, mainly in the Medicine Bow National 

Forest, approximately 30 miles southeast of Saratoga. This wilderness encompasses about 

23,500 acres, with approximately 750 of these acres in northern Colorado. The Platte River 

Wilderness is accessed by Wyoming State Highway 230 and Forest Service roads. Elevations in 

this wilderness area range from about 6,000 to 9,000 feet 

13.4 Huston Park Wilderness 

Huston Park Wilderness is located in southern Wyoming in the Medicine Bow National Forest, 

approximately 25 miles south/southwest of Saratoga and encompasses about 30,600 acres. This 

wilderness area is accessed from Wyoming State Highway 70 and Forest Service roads. 

Elevations in Huston Park Wilderness range from approximately 6,000 to 10,000 feet. 

13.5 Encampment River Wilderness 

Encampment River Wilderness is located in southern Wyoming in the Medicine Bow National 

Forest, approximately 25 miles south of Saratoga, and encompasses about 10,100 acres. Access 

to this wilderness area is from Wyoming State Highways 70 and 230 and Forest Service roads. 

Elevations in this wilderness range from about 6,000 to 10,000 feet. 

E-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

14.0 Wilderness Study Areas 

No Wilderness Study Areas (WSA) are located within or immediately adjacent to the Seminoe 

Road EIS analysis area. The WSAs in the broader general area include: 

3⁄4 Adobe Town 

3⁄4 Encampment River Canyon 

3⁄4 Farris Mountains 

3⁄4 Prospect Mountain 

3⁄4 Bennett Mountains 

14.1 Adobe Town 

The Adobe Town WSA is located 80 miles southwest of Rawlins and contains an estimated 

85,700 acres. Approximately 11,000 acres of this WSA were recommended for actual Wilderness 

status in a 1992 BLM report to Congress. 

14.2 Encampment River Canyon 

The Encampment River Canyon WSA is located 2 miles south of the town of Encampment and 

contains approximately 4,600 acres. This entire WSA was recommended as suitable for 

wilderness status in a 1992 BLM report to Congress. 

14.3 Ferris Mountains 

The Farris Mountains WSA is located 45 miles north of Rawlins and contains approximately 

22,300 acres. The entire WSA was recommended as suitable for wilderness designation in a 1992 

BLM report to Congress. 

14.4 Prospect Mountain 

The Prospect Mountain WSA is located about 15 miles southeast of the town of Encampment, 

adjoin the U.S. Forest Service’s Platte River Wilderness and contains approximately 4,350 acres. 

Seminoe Road Gas Development Project E-11 
Draft Environmental Impact Statement November 2005 

This entire WSA was recommended suitable for wilderness designation in a 1992 BLM report to 

Congress. 

14.5 Bennett Mountains 

The Bennett Mountains WSA is located northeast of the Seminoe Reservoir, about 32 miles 

northeast of Rawlins and approximately 4 miles north of the northern boundary of the Seminoe 

Road EIS analysis area. This WSA contains approximately 6,000 acres; however, this WSA was 

not recommended as suitable for wilderness status in the 1992 BLM report to Congress. 

15.0 Agricultural Activities 

Livestock grazing has historically been and continues to be a part of the Carbon County economy. 

Cattle grazing occurs on both federal and private lands within and surrounding the Seminoe Road 

EIS analysis area. There is no irrigated agricultural land within and surrounding the EIS analysis 

area; hay production is typically confined to stretches along the North Platte River near the Town 

of Saratoga, which is upstream of the Seminoe Road EIS analysis area. 

16.0 Housing Development 

The Town of Rawlins is the region’s main population center. No major housing development is 

expected to occur in the areas within or immediately surrounding the Seminoe Road Project area. 

A small development known as Miller Estates is platted along the North Platte River as shown on 

Figure 19, Regional Activity. To date, only one building and well permit has been submitted for 

this development. 

The “boat club” is a small un-incorporated area north of the EIS analysis area on private land 

adjacent to the Seminoe Reservoir. This “boat club” is an area which contains mobile homes and 

is primarily used for summer recreational activities on the reservoir. 

17.0 Historic Sites 

Fort Steele is an historic site located east of the Town of Sinclair, near where Interstate 80 

crosses the North Platte River. This site was originally established in June 1868 by the U.S. 

E-12 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

government to protect the Union Pacific Railroad from Indian attacks. See also Section 3.10, 

Cultural Resources. 

18.0 Other Potential Projects 

A Texas company (Houston-based DKRN Energy LLC) has announced a proposal for a plant to 

process coal into diesel, electricity and other products. DKRW Energy is contemplating the 

construction of this coal gasification and liquefaction facility on the Medicine Bow River Ranch in 

Carbon County, Wyoming. 

Seminoe Road Gas Development Project E-13 
Appendix F 

Reclamation Plan 
November 2005 Draft Environmental Impact Statement

Contents

1.0 Introduction ................................................................................................. F-1

2.0 Reclamation Goals and Objectives ............................................................... F-1

3.0 Reclamation Schedule.................................................................................. F-2

4.0 Construction and Interim Reclamation ....................................................... F-3

4.1 Topsoil Removal ............................................................................................... F-3

4.2 Erosion and Sediment Control ......................................................................... F-4

4.3 Interim Revegetation ....................................................................................... F-5

4.4 Noxious Weed Control...................................................................................... F-5

5.0 Concurrent Reclamation .............................................................................. F-5

6.0 General Reclamation Practices .................................................................... F-5

6.1 Decommissioning and Removal of Facilities .................................................... F-6

6.2 Recontouring and Regrading ........................................................................... F-6

6.3 Topsoil Replacement ........................................................................................ F-7

6.4 Topsoil Sampling and Fertilization.................................................................... F-7

6.5 Mulching........................................................................................................... F-7

6.6 Revegetation.................................................................................................... F-7

6.7 Reclamation Management and Monitoring...................................................... F-7

Seminoe Road Gas Development Project F-i 
November 2005 Draft Environmental Impact Statement

Appendix F – Reclamation Plan

1.0 Introduction 

The purpose of reclamation is to return disturbed areas to a stabilized and productive condition 

following natural gas development and production activities and to protect long-term land, water 

and air resources in the area. Bureau of Land Management (BLM) reclamation policies are to 

ensure the return of disturbed lands to productive uses consistent with land management policies. 

Each Application to Permit Drilling (APD) approval would require a reclamation plan acceptable to 

the BLM, and one that would conform to other appropriate federal, state and Carbon County 

regulations and guidelines. The reclamation plan would describe measures to reduce long-term 

impacts with the goal of returning the land to a productive state similar to that which existed on 

the site prior to natural gas development and production. 

The BLM understands that reclamation practices and technology are ever evolving and 

improving. Although reclamation practices have become an integral component of activities such 

as coal mining, highway construction, and oil and gas exploration and development activities, and 

existing measures have proved to be successful, it is expected that there will be future 

improvements in reclamation planning as techniques are refined or expanded. The BLM would 

work with the Proponent to take advantage of opportunities to explore new reclamation 

techniques and new methods for erosion control. 

2.0 Reclamation Goals and Objectives 

The current land use within the Seminoe Road Project EIS analysis area is primarily for 

rangeland for cattle grazing and wildlife habitat. The emphasis of the reclamation plan would be 

to create habitats similar to what currently exists. 

The reclamation plan would incorporate the following basic goals: 

3⁄4 Establishment of stable surface, topographic and drainage conditions that are compatible 

with the surrounding landscape and that control erosion, water quality and air quality 

impacts from the operation; 

Seminoe Road Gas Development Project F-1 
Draft Environmental Impact Statement November 2005

3⁄4 Establishment of surface soil conditions that are conducive to regeneration of a stable 

vegetative community through removal, stockpiling, and reapplication of topsoil material; 

3⁄4 Revegetation of disturbed areas using species adapted to site conditions and approved 

by the BLM in order to establish long-term productive self-sustaining, biotic communities 

compatible with future land uses and comparable to what currently exists on the site; 

3⁄4 Consideration of public, livestock and wildlife safety including proper plugging of 


abandoned drill holes and removing production structures or facilities that could


constitute future hazards; and, 


3⁄4 Retaining access roads across the EIS analysis area where desired by the BLM and the 

private landowners. 

The post mining land uses on BLM administered lands would be managed for grazing, wildlife 

habitat, and dispersed recreation, or other land use emphasis developed for the area through the 

BLM’s resource management planning. 

3.0 Reclamation Schedule 

Reclamation measures would be incorporated into design work at the start of the Seminoe Road 

Project and would be an integral part of APD permitting and project development and operations. 

Three types of reclamation would be scheduled and implemented at the Seminoe Road Project. 

These are: 

3⁄4 Interim reclamation 


3⁄4 Concurrent reclamation 


3⁄4 Final reclamation


During the life of the Seminoe Road Project, interim reclamation would occur to reduce erosion 

and the potential for water quality degradation. Interim reclamation refers to reclamation efforts on 

lands disturbed during the course of the construction and development activities and is intended 

to temporarily stabilize an area prior to concurrent or final reclamation. Interim reclamation would 

include revegetation to reduce erosion and sediment. Topsoil would probably not be applied to 

interim revegetatated area. Mulch would be applied, as appropriate, following seeding. The areas 

F-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

which would require interim reclamation include temporary road cuts/embankments and topsoil 

stockpiles. 

Concurrent reclamation refers to reclamation activities which can be implemented at the same 

time as ongoing construction activities and drilling operations. Concurrent reclamation activities 

would be initiated as soon as practical after construction activities and drilling operations in a 

particular area are completed, thus minimizing erosion and sedimentation problems. Such areas 

would include road outslopes (cuts and fills) for permanent roadways, areas disturbed during 

installation (burial) of electric utility lines and water and gas pipelines, and areas at well pad sites 

no longer needed for operational drilling activities. 

Final reclamation activities would be completed upon cessation of natural gas production from the 

Seminoe Road Project. The areas to undergo final reclamation upon project closure would 

include well pad sites, access roads (those not needed for long-term land use purposes), 

compressor site facilities, and water treatment facilities. 

In general, reclamation activities (whether interim, concurrent and/or final) would be timed to take 

advantage of optimal climatic conditions. Seedbeds would be prepared and seeding would be 

completed generally in the late summer or fall months to take advantage of winter and spring 

moisture. 

4.0 Construction and Interim Reclamation 

As part of construction activities (roads, well pads, and gas, water and electric utility installations), 

the following reclamation steps would be undertaken: 

3⁄4 Topsoil would be removed and stockpiled (or reapplied as part of concurrent reclamation 

activities); 

3⁄4 Erosion and sediment control would be implemented and installed; and 

3⁄4 Interim reclamation would be implemented. 

4.1 Topsoil Removal 

Topsoil suitable for revegetation would be salvaged and stockpiled prior to any construction 

activities. Topsoil salvage would be conducted using dozers, front-end loaders, scrapers, haul 

trucks, and other equipment, as appropriate. The salvage stockpile would be placed in 

Seminoe Road Gas Development Project F-3 
Draft Environmental Impact Statement November 2005

designated stockpiles; this could include “windrowing” topsoil adjacent to roads and utility line 

installations. Stockpiled topsoil would be revegetated with an interim seed mixture to reduce the 

potential of wind and water erosion. 

4.2 Erosion and Sediment Control 

Erosion and sediment control would be an important component of construction activity. These 

practices would be implemented to eliminate excess surface runoff across disturbed areas and to 

avoid sedimentation and erosion outside of those areas needed for natural gas operations and 

production. Erosion and sediment control practices include the following measures: 

3⁄4 Disturbed areas would be kept to a minimum at any given time through phased 

disturbance and concurrent reclamation. 

3⁄4 Appropriate drainage structures would be installed as part of access road construction. 

These would include side ditching, water bars, culverts and sediment traps. 

3⁄4 Rapidly developing vegetation species would be planted as part of interim reseeding to 

promote rapid stabilization. 

3⁄4 Seeding would occur in the first appropriate season after topsoil stockpiling and/or 

redistribution. 

3⁄4 Mulches would be applied to aid in erosion control and moisture retention. 

3⁄4 Interim seeding would be used to stabilize inactive and disturbed areas. 

3⁄4 Roads and water control structures would be maintained periodically as needed. 

3⁄4 Reclamation grading would be conducted to minimize erosion potential. 

3⁄4 Reclaimed areas would be inspected after major storm events. Any rills or gullies greater 

than 6 inches deep that develop would be stabilized and revegetated. 

3⁄4 Sediment control measures (side ditches along roads, culverts, etc.) would be maintained 

until reclamation efforts are completed and such sediment control structures are no 

longer needed. 

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November 2005 Draft Environmental Impact Statement

4.3 Interim Revegetation 

Stockpiled soil would be protected from wind and water erosion. During the first normal planning 

season following development of soil salvage, soil stockpiles would be seeded with an interim 

seed mixture. 

In addition, following construction activities, areas such as cut and fill embankments along roads 

should also be seeded to reduce the potential of wind and water erosion. 

Certain areas around electric substations, storage areas, compressor buildings, producing 

wellheads, etc., would not be re-seeded in order to reduce potential fire hazard to these areas. 

Areas not revegetated following construction activities should be covered with gravel to reduce 

aesthetic impacts and limit erosion potential. These areas include roads, production well pad 

areas, sites around buildings and electric substations. 

4.4 Noxious Weed Control 

Necessary control measures utilizing various mechanical, biological, cultural and chemical control 

techniques would be implemented to prevent and restrict the spread of noxious weeds. 

5.0 Concurrent Reclamation 

Because the Seminoe Road Project would be a phased operation, opportunities for concurrent 

reclamation exist. As mentioned earlier, concurrent reclamation refers to those reclamation 

activities that can be implemented at the same time as ongoing production and development 

activities. Concurrent reclamation activities would be conducted on well pad sites not needed for 

operational production, utility corridors (water and gas pipelines, buried electric lines) have been 

buried, and along road right of ways. Concurrent reclamation would be essentially final 

reclamation, as there would be no need to re-enter these areas once reclamation activities are 

complete. Concurrent reclamation would follow the procedures outlined in Section 6.0, General 

Reclamation Practices. 

6.0 General Reclamation Practices 

The general steps used in reclaiming disturbed areas are as follows: 

3⁄4 Decommissioning and Removal of Facilities 

Seminoe Road Gas Development Project F-5 
Draft Environmental Impact Statement November 2005

3⁄4 Recontouring and Regarding 

3⁄4 Topsoil Replacement 

3⁄4 Topsoil Sampling and Fertilization 

3⁄4 Mulching 

3⁄4 Revegetation 

3⁄4 Reclamation Management and Monitoring 

6.1 Decommissioning and Removal of Facilities 

The following permanent cessation of production operations, salvageable equipment, 

instrumentation and furniture would be removed from the Seminoe Road Project site. The BLM 

does not anticipate any ongoing beneficial use for structures and facilities following project 

closure; however, the BLM would coordinate with the Proponent and any private landowners 

regarding possible beneficial use. Assuming there is no ongoing beneficial use, any structures 

and facilities on site would be dismantled and removed at the time of permanent operational 

closure. This would include well site production facilities (including separator building and well 

head infrastructure), compressor buildings, electric substations, any overhead electric 

transmission lines, maintenance and storage buildings, and water treatment facilities. 

Salvageable equipment would be moved to another natural gas project, sold or properly disposed 

of off site. Unsalvageable portions of any buildings and facilities, such as foundations, would be 

broken up and buried on site. Well bores (drill holes) would be abandoned and plugged in 

accordance with BLM and Wyoming Oil and Gas Commission (WOGC) regulations, standards 

and guidelines. The underground gas gathering pipelines, water pipelines, and electric 

distribution lines would be left buried in place. 

6.2 Recontouring and Regrading 

Disturbed areas would be recontoured and regraded to blend into surrounding topography. 

Compacted areas such as road and well pads would be ripped and or disced prior to replacing 

topsoil material. Any recontouring and regrading program would also involve removal of culverts 

and restoration of surface water channels to handle flows through the area. 

F-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

6.3 Topsoil Replacement 

Following regarding activities, disturbed sites would be covered with topsoil. Topsoil would be 

respread by scraper and/or bulldozer, possibly in combination with front-end loaders and trucks. 

Stockpiled topsoils would be reapplied to regraded areas in a uniform thickness, approximately 6 

to 12 inches in depth. Topsoil would serve as the rooting zone for revegetation. 

6.4 Topsoil Sampling and Fertilization 

Following replacement, topsoil samples would be analyzed for pH, nitrogen, phosphorous and 

potassium to determine its fertility status. In the event that soil amendments or fertilizers are 

needed, they would be applied at levels recommended by the BLM prior to revegetation. 

6.5 Mulching 

If determined necessary to aid in initial stabilization and erosion control, wood fiber mulch, straw, 

or erosion control/mulch blankets would be applied to reduce initial erosion and sedimentation, 

promote stabilization and enhance seed germination. 

6.6 Revegetation 

Seeding would be conducted by either drilling or broadcast seeding. Seeding would generally be 

conducted in the late summer or fall of the year to take advantage of winter and spring moisture. 

Seed mixtures used for permanent revegetation would be based upon recommendations of the 

BLM and other public sources for reclamation work in south-central Wyoming. 

6.7 Reclamation Management and Monitoring 

Newly reclaimed areas would be managed and monitored by the Proponent consistent with 

reclamation goals and BLM revegetation success criteria outlined in future APD approvals. 

Reclaimed sites would be examined periodically during the first several years after revegetation 

to determine the effectiveness of the reclamation program. The success of revegetation would be 

monitored during this time to assure erosion has been prevented, invasion by noxious weeds 

prevented and appropriate species re-establishment has been occurring. Maintenance would be 

conducted on site as necessary to ensure establishment of appropriate vegetation species. 

Seminoe Road Gas Development Project F-7 
Appendix G 

Hazardous Materials Management Plan 
November 2005 Draft Environmental Impact Statement

Appendix G – Hazardous Materials Management Plan

Contents

1.0 Introduction ................................................................................................. G-1

2.0 Hazardous or Extremely Hazardous Materials ............................................ G-1

2.1 Fuels .................................................................................................................G-1

2.2 Lubricants/Solvents..........................................................................................G-2

2.3 Antifreeze.........................................................................................................G-2

2.4 Drilling Materials...............................................................................................G-2

2.5 Cementing/Plugging ........................................................................................G-2

2.6 Fracturing.........................................................................................................G-2

2.7 Miscellaneous Materials....................................................................................G-2

3.0 Spill Prevention and Control Countermeasure Plan ................................... G-2

4.0 Emergency Response Plans .......................................................................... G-3

5.0 Hazard Communication Program................................................................. G-3

Tables 

Table G-1, List of Hazardous and Extremely Hazardous Materials....................................G-3

Seminoe Road Gas Development Project G-i 
November 2005 Draft Environmental Impact Statement

1.0 Introduction 

Numerous local, state and federal laws, regulations and guidelines oversee the use, transport, 

and disposal of hazardous materials. The agencies involved include: 

3⁄4 Bureau of Land Management (BLM) through Instruction Memorandums #WY-93-344 & 

WY-94-059 

3⁄4 Environmental Protection Agency (EPA) through the Resource Conservation and 

Recovery Act (RCRA), Superfund Amendments and Reauthorization Act of 1986 (SARA), 

Clean Water Act, Toxic Substances Act (TSCA), and Clean Air Act 

3⁄4 U.S. Department of Transportation (DOT) 


3⁄4 U.S. Occupational Safety and Health Administration (OSHA)


3⁄4 Wyoming Department of Environmental Quality (WDEQ) 


3⁄4 Wyoming Department of Transportation (WDOT)


2.0 Hazardous or Extremely Hazardous Materials 

A listing of possible hazardous and extremely hazardous materials (hazardous materials) that 

could be present on site during construction, development, production and reclamation activities 

at the Seminoe Road Project are set forth in Table G-1, List of Hazardous and Extremely 

Hazardous Materials. Hazardous materials are those substances listed in EPA’s Consolidated 

List of Chemicals Subject to Reporting Under Title III of the Superfund Amendments and 

Reauthorization Act (SARA-1986). Extremely hazardous materials are those substances listed in 

40 CFR 355. 

Examples of hazardous materials that could be present at the Seminoe Road Project include 

fuels, lubricants, solvents, antifreeze, drilling muds, borehole plugging materials, and fracturing 

substances. 

2.1 Fuels 

Gasoline and diesel fuel would be used to power employee vehicles, transport vehicles, drill rigs, 

and construction equipment. 

Seminoe Road Gas Development Project G-1 
Draft Environmental Impact Statement November 2005

2.2 Lubricants/Solvents 

Lubricants include motor oil, greases, hydraulic and transmission fluids, and other lubricating oils. 

Solvents are substances like acetone and methanol used to clean equipment parts. 

2.3 Antifreeze 

Antifreeze keeps engines from overheating in the summer and freezing in the winter. Ethylene 

glycol is a common chemical compound used for antifreeze. 

2.4 Drilling Muds 

Drilling rigs use water-based “muds,” known as drilling fluids that lubricate the drill hole and cool 

the drill bit. Common drilling fluids include barite and bentonite. 

2.5 Cementing/Plugging 

Drill holes must be abandoned in accordance with BLM and state regulations. This includes 

plugging with materials such as bentonite, cement, and diatomaceous earth. 

2.6 Fracturing 

Fracturing is a method of formation stimulation, typically used to improve formation permeability, 

which would increase oil and gas production. In fracturing, fluids are pumped under pressure into 

the wellbore. These fluids can include quantities of methanol, sand and naphthalene. 

2.7 Miscellaneous Materials 

Various miscellaneous materials can be present at an oil and gas operation; these include 

batteries, cleaners, fertilizers, herbicides, lubricants, paints and starting fluids. 

3.0 Spill Prevention and Control Countermeasure Plan 

EPA requires that a spill prevention and control countermeasure plan (SPCC) be maintained and 

available for review on site. A SPCC will describe the facilities and processes that would be used 

to prevent, handle and/or control spills of petroleum products and hazardous materials. 

G-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

4.0 Emergency Response Plans 

Oil and gas product projects require an emergency response plan (ERP), which would outline the 

basic procedures to be followed in the event of an emergency that might involve a fire, explosion, 

major spill or dangerous weather condition. An emergency response coordinator must be 

identified in an ERP, along with emergency phone numbers, which should also be displayed at 

key locations throughout the project site and in project vehicles. 

5.0 Hazard Communication Program 

Material Safety Data Sheets (MSDS) must be available on site for any hazardous materials 

stored, used or disposed of on site. MSDS describe the hazardous materials common name, 

chemical and physical makeup, health effects from exposure, and recommended first aid, if 

exposed to the material. 

Table G-1, List of Hazardous and Extremely Hazardous Materials 

Source Hazardous Substances1 Extremely Hazardous 

Substances 

Drilling Material 

Barite Barium compounds 

Fine mineral fibers 

Bentonite Fine mineral fibers 

Caustic Soda Sodium hydroxide 

Glutaraidehyde Isopropyl alcohol 

Lime Calcium hydroxide 

Mica Fine mineral fibers 

Modified Tannin Ferros sulfate 

Fine mineral fibers 

Phoephaza Esters Methanol 

Polyacrylamides 

Acrylamide 

PAHs 

Petroleum distillates 

POM 

Retarders Fine mineral fibers 

Anionic Polyacrylamide Acrylamide 

Polyanionic Cellulose Fine mineral fibers 

Cementing/Plugging 

Bentonite Fine mineral fibers 

Anti-foamer Glycol ethers 

Calcium Chloride Flake Fine mineral fibers 

Cellophane Flake Fine minerals fibers 

Cements Aluminum oxide 

Fine mineral fibers 

Chemical Wash Ammonium oxide 

Glycol ethers 

Diamaceous Earth Fine mineral fibers 

Extenders Aluminum oxide 

Fine mineral fibers 

Seminoe Road Gas Development Project G-3 
Draft Environmental Impact Statement November 2005

Source Hazardous Substances1 Extremely Hazardous 

Substances 

Fluid Loss Additive 

Acrylamide 

Fine mineral fibers 

Napthalene 

Friction Reducer 

Fine mineral fibers 

Napthalene 

PAHs 

POM 

Mud Flash Fine mineral fibers 

Retarder Fine mineral fibers 

Salt Fine mineral fibers 

Silica Flour Fine mineral fibers 

Fracturing Materials 

Biocides 

Fine mineral fibers 

PAHs 

POM 

Breakers 

Ammonium persulphate 

Ammonium sulphate 

Copper compounds 

Ethylene glycol 

Fine mineral fibers 

Glycol ethers 

Clay Stabilizer 

Fine mineral fibers 

Glycol ethers 

Isopropyl alcohol 

Methanol 

PAHs 

POM 

Crosslinkers 

Ammonium chloride 

Methanol 

Potassium hydroxide 

Zirconium nitrate 

Zirconium sulfate 

Foaming Agency Glycol ethers 

Gelling Agent 

Benzene 

Ethylbenzene 

Methyl tert-butyl ether 

Napthalene 

PAHs 

POM 

Sodium hydroxide 

m-Xylene 

o-Xylene 

p-Xylene 

pH Buffers 

Acetic acid 

Benzoic acid 

Fumeric acid 

Hydrochloric acid 

Sodium hydroxide 

Sands Fine mineral fibers 

Solvents Glycol ethers 

G-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Source Hazardous Substances1 Extremely Hazardous 

Substances 

Surfactants 

Glycol ethers 

Isopropyl alcohol 

Methanol 

PAHs 

POM 

Corrosion Inhibitor 

Production Products 

Natural Gas 

n-Hexane 

PAHs 

POM 

Produced Water/Drill Cuttings 

Fuels 

Diesel Fuel 

Benzene 

Cumene 

Ethylbenzene 

Methyl tert-butyl ether 

Naphthalene 

PAHs 

POM 

Toluene 

m-Xylene 

o-Xylene 

p-Xylene 

Gasoline 

Benzene 

Cumene 

Cyclohexane 

Ethylbenzene 

n-Hexane 

Methyl tert-butyl ether 

Naphthalene 

PAHs 

POM 

Tetraethyl lead 

Toluene 

m-Xylene 

o-Xylene 

p-Xylene 

Natural Gas 

n-Hexane 

PAHs 

POM 

Propane Propylene 

Pipeline Materials 

Coating Aluminum oxide 

Cupric Sulfate Solution Cupric sulfate 

Sulfuric acid 

Diethanolamine Diethanolamine 

LP Gas 

Benzene 

n-Hexane 

Propylene 

Molecular Sieves Aluminum oxide 

Pipeline Primer Naphthalene 

Toluene 

Potassium Hydroxide Solution Potassium hydroxide 

Seminoe Road Gas Development Project G-5 
Draft Environmental Impact Statement November 2005

Source Hazardous Substances1 Extremely Hazardous 

Substances 

Rubber Resin Coatings 

Acetone 

Coal tar pitch 

Ethyl acetate 

Methyl ethyl ketone 

Toluene 

Xylene 

Emissions 

Gases 

Formaldehyde 

Nitrogen dioxide 

Ozone 

Sulfur dioxide 

Sulfur trioxide 

Hydrocarbons 

Benzene 

Ethylbenzene 

n-Hexane 

PAHs 

Toluene 

m-Xylene 

o-Xylene 

p-Xylene 

Particulate Matter 

Barium 

Cadmium 

Copper 

Fine mineral fibers 

Lead 

Manganese 

Nickel 

POM 

Zinc 

Miscellaneous Materials 

Acids 

Acetic anhydride 

Formic acid 

Sodium chromate 

Sulfuric acid 

Antifreeze, heat control, and 

dehydration agents 

Acrolein 

Cupric sulfate 

Ethylene glycol 

Freon 

Phosphoric acid 

Potassium hydroxide 

Sodium hydroxide 

Triethylene glycol 

Batteries 

Cadmium 

Cadmium oxide 

Lead 

Nickel hydroxide 

Potassium hydroxide 

Sulfuric acid 

Biocides 

Formaldehyde 

Isopropyl alcohol 

Methanol 

Cleaners Hydrochloric acid 

G-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Source Hazardous Substances1 Extremely Hazardous 

Substances 

4-4’ methylene dianiline 

Acetic acid 

Ammonium bisulfite 

Basic zinc carbonate 

Diethylamine 

Dodecylbenzenesulfonic acid 

Corrosion Inhibitors Ethylene glycol 

Isobutyl alcohol 

Isopropyl alcohol 

Methanol 

Napthalene 

Sodium nitrite 

Toluene 

Xylene 

Acetic acid 

Acetone 

Ammonium chloride 

Benzoic acid 

Emulsion Breakers Isopropyl alcohol 

Methanol 

Napthalene 

Toluene 

Xylene 

Zinc chloride 

Lead-free Thread Compound Copper 

Zinc 

1,2,4-trimethylbenzene 

Barium 

Cadmium 

Copper 

n-Hexane 

Lubricants Lead 

Manganese 

Nickel 

PAHs 

POM 

Zinc 

Methanol Methanol 

Motor Oil Zinc compounds 

Aluminum 

Barium 

n-Butyl alcohol 

Cobalt 

Lead 

Paints Manganese 

PAHs 

POM 

Sulfuric acid 

Toluene 

Triethylamine 

Xylene 

Carbon disulfide 

Ethylbenzene 

Paraffin Control Methanol 

Toluene 

Xylene 

Photoreceptors Selenium 

Seminoe Road Gas Development Project G-7 
Draft Environmental Impact Statement November 2005

Source Hazardous Substances1 Extremely Hazardous 

Substances 

Scale Inhibitors 

Acetic acid 

Ethylene diamine tetra 

Ethylene glycol 

Formaldehyde 

Hydrochloric acid 

Isopropyl alcohol 

Methanol 

Nitrilotriacetic acid 

Sealants 

1,1,1-trichlorethane 

n-Hexane 

PAHs 

POM 

Solvents 

1,1,1-trichloroethane 

Acetone 

t-Butyl alcohol 

Carbontetrachloride 

Isopropyl alcohol 

Methyl ethyl ketone 

Methanol 

PAHs 

POM 

Toluene 

Xylene 

Starting Fluid Ethyl ether 

Surfactants 

Ethylene diamine 

Isopropyl alcohol 

Petroleum naphtha 

Notes: 

1. PAH = polynuclear aromatic hydrocarbons, POM = polycylic organic matter 

G-8 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

GENERAL AIR QUALITY MITIGATION INFORMATION


(This information has been provided by Wyoming BLM State Office in Cheyenne) 


Type of 

Mitigation 

Estimated Cost of 

Mitigation 

Environmental 

Cost 

Environmental 

Benefit 

Potential 

Limitations 

NOx and CO Mitigation Measures 

Utilize selective 

catalytic reduction 

on compressors. 

Relatively expensive 

as compared to nonselective catalysts. 

Typical costs are 

$125/horsepower 

(EPA Cost Control 

Manual January 

2002). 

Requires the use and 

storage of ammonia, 

which presents health 

and safety issues. 

Results in increased 

ammonia emissions 

which may contribute to 

the formation of 

ammonium sulfates and 

increased visibility 

degradation. 

NOx emission rate 

reduced to 0.1 g/hphr. Reduced 

ammonium nitrate 

formation and 

resulting visibility 

impacts. 

Not applicable for 2­

stroke engines. 

Application of nonselective catalytic 

reduction. 

$5,000 to $25,000 

per unit. 

Regeneration/disposal 

costs for catalysts. 

As a result of the 

BACT process, 

average NOx 

emission rates for 

Wyoming engines 

100 hp or greater is 

1.0 g/hp-hr. The 

application of nonselective catalysts 

may reduce the NOx 

emission rate to 0.7 

g/hp-hr for some 

types of engines. 

Not applicable for 

lean-burn or 2-stroke 

engines. 

Utilize compressors 

driven by electrical 

motors. 

Capital costs equal 

40% of gas turbine 

costs. Operating cost 

dependent upon the 

location of high 

voltage power lines. 

Displaced air emissions 

from compressor units to 

electrical power plant. 

May potentially 

relocate emissions 

away from sensitive 

Class I areas. 

Requires high 

voltage power lines. 

Increased diameter 

of sales pipelines. 

With larger diameter 

sales pipelines, 

capital costs 

increase while 

operating costs 

decrease. 

Slightly more surface 

disturbance. 

Lower pipeline 

pressures resulting 

in lower 

compression hp 

requirements. 

Utilize wind 

generated electricity 

to power 

compressors. 

Capital costs are 

very large. 

Visual impacts from 

generation equipment. 

Increased mortality of 

birds including raptors. 

Reduced use of 

fossil fuels and 

associated 

emissions. 

Location of wind 

generation facilities 

is critical. Requires 

consistent strong 

winds for economic 

operation. Also 

requires high voltage 

transmission lines 

between generation 

facility and 

compressor stations. 

Seminoe Road Gas Development Project G-9 
Draft Environmental Impact Statement November 2005

Type of 

Mitigation 

Estimated Cost of 

Mitigation 

Environmental 

Cost 

Environmental 

Benefit 

Potential 

Limitations 

Increased 

monitoring. 

Unknown. None. The WDEQ-AQD 

currently has an 

emission tracking 

agreement with the 

BLM. The Amended 

Letter of Agreement 

for Tracking 

Nitrogen Oxide 

Emissions dated 

April 2000 calls for 

annual reports 

tracking changes in 

NOx emission 

beginning January 1, 

1996. 

The monitoring of 

emission sources 

provides improved 

information for 

estimating impacts, 

but does not reduce 

the magnitude of the 

impacts. 

Phased 

development. 

Short-term loss of 

state and federal 

royalties. 

Emissions generated at 

a lower rate averaged 

over a longer period. 

Peak emissions and 

associated impacts 

reduced. 

Administration / 

jurisdiction 

limitations – The 

WDEQ-AQD is the 

regulatory authority 

for air quality within 

the state of 

Wyoming. 

Therefore, the BLM 

cannot limit or 

otherwise restrict 

development based 

upon potential air 

quality impacts. 

Economic limitations 

– A minimum 

production rate is 

required to cost 

effectively develop 

the resource while 

maintaining the 

processing and 

transportation 

infrastructure. 

Particulate Matter Mitigation Measures 

Increase water 

application rate to 

achieve greater than 

50% fugitive dust 

control. 

Varies with the 

source of the water 

and the trucking 

distance. 

None. Can achieve fugitive 

dust control rates up 

to 95%. 

Diminishing returns 

per gallon of water 

applied. Water must 

be applied at much 

greater rates to 

achieve control 

efficiencies greater 

than 75%. 

Unpaved road dust 

suppressant 

treatments. 

$2,400 to $50,000 

per mile. 

Treatment chemicals 

have the potential to 

negatively impact water 

quality. 

Estimated 20% to 

100% reduction in 

fugitive dust 

emissions. 

Administrative 

control of speed 

limits. 

Relatively low costs 

for installation of 

signs and 

enforcement. 

None. Slower speeds may 

provide 20% to 50% 

reduction in dust 

emissions. 

State or county may 

retain authority for 

determining speed 

limits on primary 

roads. 

G-10 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Type of 

Mitigation 

Estimated Cost of 

Mitigation 

Environmental 

Cost 

Environmental 

Benefit 

Potential 

Limitations 

Installation of 

remote telemetry. 

Approximately 

$13,000 per well. 

None. Reduction in vehicle 

miles traveled and 

associated vehicle 

emissions during 

production 

operations. No 

benefit for 

construction 

operations which 

generate the 

greatest amount of 

PM. 

Effective only for the 

production phase of 

the operations. 

Would have no 

impact upon 

construction 

activities which 

generate the 

greatest amount of 

particulate matter. 

Gravel roads. Approximately 

$9,000 per mile. 

None. Estimated 30% 

reduction in fugitive 

road dust. 

Pave roads. Approximately 

$11,000 to $60,000 

per mile. 

None. Estimated 90% 

reduction in fugitive 

road dust. 

Phased 

development. 

Short-term loss of 

state and federal 

royalties. 

Emissions generated at 

a lower rate averaged 

over a longer period. 

Peak emissions and 

associated impacts 

reduced. 

Administration / 

jurisdiction 

limitations – The 

WDEQ-AQD is the 

regulatory authority 

for air quality within 

the state of 

Wyoming. 

Therefore, the BLM 

cannot limit or 

otherwise restrict 

development based 

upon potential air 

quality impacts. 

Economic limitations 

– A minimum 

production rate is 

required to cost 

effectively develop 

the resource while 

maintaining the 

processing and 

transportation 

infrastructure. 

Seminoe Road Gas Development Project G-11 
Appendix H 

Air Quality Information 
Draft Environmental Impact Statement November 2005

Contents

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

2.0 PROTOCOL DEVELOPMENT PROCESS ............................................................. H-2

3.0 EMISSION INVENTORY ...................................................................................H-3

3.1 Project Emission Inventory ..............................................................................H-3

3.1.1 Construction Emissions ................................................................................H-4

3.1.2 Production Emissions ...................................................................................H-5

3.1.3 Total Field Emissions ....................................................................................H-7

3.2 Regional Emissions Inventory ..........................................................................H-8

4.0 NEAR-FIELD MODELING ................................................................................. H-9

4.1 Particulate Matter Near-Field Modeling Results ............................................H-10

4.2 SO2 Near-Field Modeling Results ....................................................................H-11

4.3 NO2 and CO Near-Field Modeling Results .......................................................H-11

5.0 FAR-FIELD / CUMULATIVE IMPACTS MODELING........................................... H-13

5.1 Modeling Methodology ..................................................................................H-14

5.2 Project Modeling Scenarios............................................................................H-15

5.3 Meteorological Model Input And Options.......................................................H-16

5.4 Dispersion Model Input And Options..............................................................H-17

5.4.1 Chemical Species ........................................................................................H-17

5.4.2 Model Receptors ........................................................................................H-17

5.4.3 Source Parameters .....................................................................................H-18

5.5 Criteria Pollutant Background Data ...................................................... H-18

5.6 Visibility Background Data ..................................................................... H-19

5.7 Lake Chemistry Background Data.......................................................... H-20

5.8 Impact Assessment................................................................................. H-20

5.8.1 Concentration.............................................................................................H-21

5.8.2 Deposition ..................................................................................................H-22

5.8.3 Sensitive Lakes ...........................................................................................H-22

5.8.4 Visibility ......................................................................................................H-22

Seminoe Road Gas Development Project H-i 
Draft Environmental Impact Statement November 2005

Tables

Table H-1, Single Well Construction Emissions Summary ..........................................................H-5


Table H-2, Single Well Production Emissions Summary .............................................................H-7


Table H-3, Estimated Annual In-Field Emissions Summary ........................................................H-8


Table H-4, Summary of Regional Inventory Emissions Changes from January 1, 2001 to H-


March 31, 2004 .........................................................................................................H-9


Table H-5, Maximum Modeled PM10 and PM2.5 Impacts ............................................................H-11


Table H-6, Maximum Modeled and SO2 Impacts .......................................................................H-11


Table H-7, Maximum Modeled NO2 and CO Impacts ................................................................H-12


Table H-8, Maximum Emissions.................................................................................................H-15


Table H-9, Far-field Analysis Background of Ambient Air Quality Concentrations ....................H-19


Table H-10, IMPROVE Background Aerosol Extinction Values.................................................H-19


Table H-11, Background ANC Values for Acid Sensitive Lakes ................................................H-20


Table H-12, FLAG Report Background Extinction Values ........................................................H-23


Table H-13, Monthly Relative Humidity Factors From IMPROVE Sites.....................................H-24


Figures 

Figure 5, Projected Build-out Scenario (Mesaverde Formation) 


Figure 6, Projected Build-out Scenario (Medicine Bow and Fox Hills Formations) 


Figure 20, Air Quality Modeling Domain


H-ii Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

Appendix H – Air Quality Information 

1.0 INTRODUCTION 

The Bureau of Land Management (BLM) decided that a joint far-field (cumulative) air quality 

impact assessment should be prepared to encompass both the Seminoe Road Gas Development 

(Seminoe Road) and the Atlantic Rim Gas Development (Atlantic Rim) projects. Both of these 

coalbed natural gas projects are located in south-central Wyoming and are tracking on similar 

development schedules. 

In conjunction with the joint far-field assessment, the BLM further decided that separate near-field 

air quality analyses should be assembled for each project to assess localized impacts within and 

immediately surrounding their individual development areas. 

Government air quality specialists from the BLM, the U.S. Environmental Protection Agency 

(EPA), the Wyoming Department of Environmental Quality (DEQ) Air Quality Division, the 

U.S.D.A. Forest Service (Forest Service), and the U.S.D.I. National Park Service worked together 

as “stakeholders” on this air quality impact assessment. 

Air quality experts from TRC Environmental Consultants (TRC) and Compliance Partners Inc. 

(CPI) were retained to assist in the development of detailed study protocol and to perform the 

actual modeling work. The two project proponents, Anadarko Resources Inc. (Anadarko) of the 

Atlantic Rim Project and Dudley & Associated L.L.C. (Dudley) of the Seminoe Road Project, 

provided development data and operational information and data to the stakeholders and funded 

the efforts of TRC and CPI. 

A detailed study protocol was prepared for this air quality impact assessment (TRC 2004a). This 

protocol identified the study domain boundaries and the methodologies to be used to quantify 

potential air quality impacts from the two projects. A series of meetings and conference calls 

were held in 2003 and 2004 amongst the stakeholders to assure agreement with the protocol. 

These discussions lead to joint concurrence about the study domain, the modeling approach, the 

various input data, the impact computation methods, and the results of the modeling. 

Seminoe Road Gas Development Project H-1 
Draft Environmental Impact Statement November 2005

The protocol dictated that air quality impacts be analyzed based on air emissions from project 

sources, coupled with emissions from other non-project sources within the far-field study domain, 

which was established by the stakeholders and included portions of Wyoming, Idaho, Utah, and 

Colorado. See Figure 20, Air Quality Modeling Domain. 

The non-project sources incorporated into the modeling effort included both permitted and 

reasonably foreseeable future action and development sources identified within the study domain. 

Subsequent to protocol acceptance, the following tasks were completed: 

3⁄4 Development of construction and production emission inventories for each project; 

3⁄4 Compilation of a cumulative emissions inventory within the study domain that included 

non-project sources permitted between January 1, 2001 and March 31, 2004, as well as 

other reasonably foreseeable future action and development sources 

3⁄4 Separate assessment of near-field ambient impacts for each project; 

3⁄4 Assessment of project-related and cumulative air emission impacts at EPA-designated 

Class I and sensitive Class II Prevention of Significant Deterioration (PSD) areas within 

the study domain. 

Following the completion of air emissions modeling, TRC prepared and released a 

comprehensive technical support report that presented the details and results of the air emissions 

near-field and far-field modeling work (TRC 2004b). This report, entitled Air Quality Technical 

Support Document, Atlantic Rim Natural Gas Project and the Seminoe Road Gas Development 

Project, is available for review at the BLM State Office in Cheyenne, Wyoming and the BLM 

Rawlins Field Office in Rawlins, Wyoming. The report is also available for review on the BLM 

Rawlins Field Office website. 

2.0 PROTOCOL DEVELOPMENT PROCESS 

On August 14, 2003, an initial “kick-off” meeting amongst individuals from the BLM, Anadarko, 

Dudley, TRC, and CPI was held in Cheyenne, Wyoming, to discuss the air quality aspects of the 

Seminoe Road and Atlantic Rim projects. 

At this August 2003 meeting, it was decided that a joint air emissions assessment should be 

completed for the Seminoe Road and Atlantic Rim projects, and that effort should begin with the 

H-2 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

development of a comprehensive air quality impact assessment study protocol. It was also 

decided that air quality specialists from EPA, Wyoming DEQ Air Quality Division, Forest Service, 

and National Park Service (collectively with the BLM to be identified as the “stakeholders”) should 

be invited and encouraged to participate in the review of the protocol and the actual air impact 

modeling work. 

Subsequent to this August 2003 meeting, conference calls amongst the BLM, Anadarko, Dudley, 

TRC, CPI, SEI and Holsan & Associates were conducted on September 24, 2003 and October 8, 

2003. The purpose of these ensuing discussions was to determine the status of the preliminary 

draft protocol, clarify certain project plans and details, and ascertain the timing for submitting a 

preliminary draft protocol document to the invited stakeholders. 

On November 4, 2003, a preliminary draft protocol was issued to stakeholders for review, and the 

first formal stakeholders meeting was held on November 24, 2003 in Cheyenne, Wyoming. Other 

stakeholder meetings and conference calls followed in 2004, and a final protocol document was 

released on August 23, 2004. This protocol is presented as TRC 2004a. 

3.0 EMISSION INVENTORY 

Emissions inventories were developed for both the Atlantic Rim and Seminoe Road projects, and 

for other existing and reasonably foreseeable regional sources within the study domain. Criteria 

pollutant and hazardous air pollutant (HAP) emissions were inventoried for construction and 

production activities and for ancillary facilities for use in the near-field air quality analysis. 

Criteria pollutants include nitrogen oxides (NOX), carbon monoxide (CO), sulfur dioxides (SO2), 

volatile organic compounds (VOC), and particulate matter. Particulate matter is further classified 

by its size; PM10 refers to particulate matter less than 10 microns in diameter, and PM2.5 refers to 

particulate matter less than 2.5 microns in diameter. HAP includes n-hexane, BTEX (benzene, 

toluene, ethylbenzene, and xylenes), and formaldehyde. Emission calculations were completed in 

accordance with Wyoming DEQ Oil and Gas Guidance, EPA’s AP42 emission factor 

compendium, and other accepted engineering methods (TRC 2004a). 

3.1 Project Emission Inventory 

The Seminoe Road Project would involve the development of an estimated 1,240 natural gas 

wells on up to 785 well pad sites, which are spaced at approximately one well pad site every 160 

Seminoe Road Gas Development Project H-3 
Draft Environmental Impact Statement November 2005

acres. Vehicle traffic, well pad construction, well drilling and completion activities, pipeline and 

utilities installations, and other project-related development and production activities would cause 

particulate and gaseous emissions. These actions and activities formed the basis for the air 

quality assessment for the Seminoe Road Project. A similar assessment was completed for the 

Atlantic Rim Project. 

3.1.1 Construction Emissions 

Construction-related emissions would result from well pad and access road construction and 

traffic, drill rig moving, drilling and associated traffic, pipelines and electric utility line installations 

and associated traffic, and general wind erosion from exposed areas disturbed during 

construction activities. Well pad and access road emissions would include fugitive PM10 and 

PM2.5 emissions from construction activities and traffic to and from the construction sites. Other 

criteria pollutant emissions would occur from diesel combustion in large supply trucks and other 

heavy construction equipment. Use of gravel on Seminoe Road Project area roads would reduce 

the “silt content” of the roads, thereby reducing particulate emissions. The use of water or 

chemical dust suppressant on the graveled roads was not considered as part of the emissions 

inventory for the Seminoe Road Project; however, these measures, if used, would further reduce 

traffic-related emissions from roads. 

When sufficient well pad sites are available and access to these sites has been established, drill 

rig movement and operation could commence. Emissions from these drill rig equipment 

mobilization and actual drilling activities would include fugitive particulate matter from travel to 

and from the drilling site on unpaved (but graveled) access roads within the project area and 

combustion emissions from diesel drilling engines. Drilling engine emissions were calculated 

using manufacturer’s emission data. Emissions from the well completion phase, which follows 

the drilling phase, would also include fugitive PM10 and PM2.5 emissions from traffic and 

emissions from diesel combustion in supply trucks and completion drill rigs. 

A summary of the estimated construction emissions for a single well is shown in Table H-1, 

Single Well Construction Emissions Summary. Emission factors, input parameters, and 

assumption details used in estimating emissions are provided in TRC 2004b. 

H-4 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

Table H-1, Single Well Construction Emissions Summary


Pollutant 

Well Pad and 

Access Road 

Construction 

Rig Move and 

Drilling 

Completing and 

Testing 

Pipeline 

Construction Total 

Lb/Hr Tons/ 

Well Lb/Hr Tons/ 

Well Lb/Hr Tons/ 

Well Lb/Hr Tons/ 

Well Lb/Hr Tons/ 

Well 

NOX 4.37 0.041 17.12 3.49 4.59 0.183 4.16 0.031 30.23 3.748 

CO 1.20 0.011 2.94 0.60 0.99 0.040 1.55 0.010 6.69 0.66 

SO2 0.47 0.0045 1.82 0.37 0.30 0.012 0.41 0.0031 3.0053 0.39 

PM10 29.79 0.59 3.34 0.58 2.24 0.071 7.48 0.14 42.85 1.39 

PM2.5 6.38 0.12 2.16 0.43 0.61 0.022 2.03 0.036 11.18 0.61 

VOC 0.40 0.0039 0.49 0.10 0.37 0.015 0.43 0.0031 1.70 0.12 

3.1.2 Production Emissions 

Coalbed natural gas well field production equipment and operations would also be a source of 

criteria pollutants. 

For the Seminoe Road Project, two alternatives were considered: 

(1) An electric power option with minimal use of natural gas power during phased build-out, 

mostly at isolated well pad locations (this alternative is proposed by Dudley, the project 

proponent); and, 

(2) A complete natural gas (non-electric) power option, where natural gas powered 

compressors and well pad engines would be a source of criteria pollutants and HAP. 

For both of the above alternatives, pollutant emission sources during field production would 

include the following: 

3⁄4 Travel on access roads to and from well sites within the project area; 


3⁄4 Diesel combustion emissions from supply and gravel-hauling trucks; 


3⁄4 Wind erosion from well pad disturbed areas (areas where vegetation and soil have been


removed); 

3⁄4 Natural gas-fired reciprocating internal combustion compressor engines (under the nonelectrified option); 

3⁄4 Natural gas-fired down-hole pumps installed at each well outside of the field electrification 

boundary (under the Proponent’s proposed action); and 

Seminoe Road Gas Development Project H-5 
Draft Environmental Impact Statement November 2005

3⁄4 Natural gas-fired down-hole pumps installed at each well, which would be used for entire 

project life of the well (under the non-electrified option). 

Fugitive PM10 and PM2.5 emissions would occur from road travel and wind erosion from well pad 

disturbances. NOX, CO, VOC, and PM10/PM2.5 emissions would occur from diesel combustion in 

large supply and gravel-hauling trucks traveling in the field during construction and production. 

Three compressor stations would be used during the operational life of the Seminoe Road 

Project. One of these compressor stations is currently permitted under Wyoming Permit Number 

CT-2833. Under this existing permit, the compressor is approved using natural gas. 

Under the Proponent’s proposed action, the three compressor stations would be powered with 

electricity. There would be no gaseous emissions from these electrified stations. 

Under the non-electric alternative, emissions for the remaining two compressor stations are 

assumed to be identical to the presently permitted compressor station. Each compressor station 

would have two compressor engines (1,340 hp Caterpillar 3516 LE or equivalent) and one 20 

MMSCFD glycol dehydration unit. Natural gas powered compressor station engines would be a 

source of NOX, CO, VOC, and formaldehyde. Natural gas powered dehydrators would be a 

source of NOX and CO; however, only minor amounts of HAP would be emitted from the 

dehydrators. 

The Seminoe Road Project coalbed natural gas wells would be developed in a “ring-like 

progression” outward from the existing Pilot Project as shown on Figure 5, Projected Build-out 

Scenario (Mesaverde Formation), and Figure 6, Projected Build-out Scenario (Medicine 

Bow and Fox Hills Formations). Each year, the majority of the wells would be drilled within 

that year’s designated development area. 

Under the Proponent’s proposed action, these wells would be electrified and would have no 

emissions from the installed down-hole pumps. As mentioned previously, however, there would 

be a small number of isolated wells drilled each year outside of the electrification “boundary”. 

These wells would use natural gas-fired down-hole pumps until the electric “grid” is extended 

outward to their locations. 

Under the non-electric alternative, down-hole well pumps would be powered with natural gas. 

H-6 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

Total production emissions of criteria pollutants and HAP occurring from a single electrified well 

and from a single non-electrified well are presented in Table H-2, Single Well Production 

Emissions Summary. Production emission calculations showing emission factors, input 

parameters, and assumptions are provided in detail in TRC 2004b. 

Table H-2, Single Well Production Emissions Summary 

Well Configuration Pollutant 

Traffic Emissions 

Single Well 

(tons/year) 

Production Emissions 

Single Well 

(tons/year) 

Total Emissions 

Single Well 

(tons/year) 

NOX 0.00032 -- 0.00032 

CO 0.00041 -- 0.00041 

SO2 8.85E-06 -- 8.85E-06 

PM10 0.28 -- 0.28 

PM2.5 0.043 -- 0.043 

Electrified Well VOC 0.00016 -- 0.00016 

Formaldehyde -- -- 0.000 

Benzene -- -- 0.00 

Toluene -- -- 0.00 

Ethylbenzene -- -- 0.00 

Xylenes -- -- 0.00 

n-hexane -- -- 0.00 

NOX 0.00032 1.00 1.00 

CO 0.00041 2.98 2.98 

SO2 8.85E-06 -- 8.85E-06 

PM10 0.28 -- 0.28 

PM2.5 0.043 -- 0.043 

Non-Electrified Well VOC 0.00016 1.00 1.000 

Formaldehyde -- 0.050 0.050 

Benzene -- -- 0.00 

Toluene -- -- 0.00 

Ethylbenzene -- -- 0.00 

Xylenes -- -- 0.00 

n-hexane -- -- 0.00 

3.1.3 Total Field Emissions 

Estimated annual emissions in the Seminoe Road Project area under the proposed action and 

non-electric scenario are shown in Table H-3, Estimated Annual In-Field Emissions Summary. 

Emissions assume construction and production occurring simultaneously in the field and include 

one year of maximum construction emissions plus one year of production at maximum emission 

rates. Construction emissions were calculated based on the number of wells constructed per 

year and the type of well constructed. Production emissions were calculated based on the total 

number of producing wells in the field. Total producing wells were equal to the difference in 

number of wells proposed and the number of wells constructed per year. 

Seminoe Road Gas Development Project H-7 
Draft Environmental Impact Statement November 2005

Table H-3, Estimated Annual In-field Emissions Summary


Alternative/ 

Pollutant 

Wells 

Developed 

Annual 

Construction 

Emissions 

(tons/year) 

Total 

Proposed 

Wells 

Total 

Producing 

Wells 

Wells Outside 

Electrification 

Boundary 

Annual 

Production 

Emission1 

(tons/year) 

Total 

Annual 

Emissions 

(tons/year) 

Proposed Action2 

NOx 129 309.39 1,240 71,111 9 9.35 318.74 

SO2 42.15 0.0098 42.16 

PM10 199.54 315.77 515.31 

PM2.5 73.75 47.27 121.02 

VOC 20.87 9.17 30.05 

Non-Electric Case3 

NOx 129 309.39 1,240 1,111 1,111 1,111.35 1,420.74 

SO2 42.15 0.0098 42.16 

PM10 199.54 315.77 515.31 

PM2.5 73.75 47.27 121.02 

VOC 20.87 1,111.17 1,132.05 

Notes: 

(1) Production emissions are taken from an average of the three most active years, 2008-2010. 

(2) Includes emissions from wells outside electrification boundary in year 2009. 

(3) Includes down-hole pump emissions at all producing wells. 

3.2 Regional Emissions Inventory 

Industrial sources, including oil and gas wells and associated infrastructure facilities, permitted 

between January 1, 2001 and March 31, 2004 through state air quality regulatory agencies and 

state oil and gas permitting agencies were identified for the modeling study domain (TRC 2004b). 

Those sources (or portions thereof) that had begun operations on or before March 31, 2004 were 

classified as “state-permitted sources”, while those sources not yet in operation were classified as 

reasonably foreseeable future actions. Wyoming industrial sources proposed under NEPA 

analyses were also included within the regional emissions inventory. 

When expansion was proposed for an existing industrial (oil and gas project), it was assumed that 

the developed portions of those existing industrial sources were either included in monitored 

ambient background or included in the state-permitted source inventory. The undeveloped 

portions of projects proposed under a NEPA study were classified as reasonable foreseeable 

development. These included (1) NEPA-authorized but not yet developed projects and (2) 

presently unauthorized NEPA projects for which air quality analyses were in progress. 

The inventory methodologies used to compile the regional source emissions inventory for the 

Atlantic Rim and Seminoe Road projects are provided in TRC 2004b. This document provides a 

description of the data collected, the period of record for the data collected, inclusion and 

exclusion methodology, stack parameter processing methods, and the state-specific 

H-8 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

methodologies utilized to distinguish the differences in the content and completeness of data 

obtained from each state. Values presented in Table H-4, Summary of Regional Inventory 

Emissions Changes from January 1, 2001 to March 31, 2004 represent the change in 

emissions between January 1, 2001 (the inventory start date) and March 31, 2004 (the inventory 

end-date). 

Table H-4, Regional Inventory Summary of Emissions Changes from January 1, 2001 to 

March 31, 2004 

Source/Category 

Number of 

Included 

Sources 

NOX 

(tons/year) 

SO2 

(tons/year) 

PM10 

(tons/year) 

PM2.5 

(tons/year) 

Colorado 

Excluded 353 -- -- -- --

RFD(1) 0 -- -- -- --

RFFA(2) 0 -- -- -- --

State Permitted 35 495.0 16.1 218.7 116.5 

Idaho 

Excluded 53 -- -- -- --

RFD(1) 0 -- -- -- --

RFFA(2) 0 -- -- -- --

State Permitted 3 94.73 93.67 13.62 13.62 

Utah 

Excluded 437 -- -- -- --

RFD(1) 0 -- -- -- --

RFFA(2) 0 -- -- -- --

State Permitted 12 257.6 4.8 (283.6) (283.6) 

Wyoming 

Excluded 1369 -- -- -- --

RFD(1) 44 6,224.2 55.5 48.1 48.1 

RFFA(2) 164 4,568.8 (1,394.3) (833.6) (330.0) 

State Permitted 91 2,020.72 3.6 36.6 20.4 

Total 

Excluded 2,212 -- -- -- --

RFD(1) 44 6,224.2 55.5 48.1 48.1 

RFFA(2) 164 4,568.8 (1,394.3) (833.6) -330.0 

State Permitted 141 2,868.0 118.2 (14.8) (133.1) 

Notes: 

(1) RFD=Reasonably Foreseeable Development 

(2) RFFA=Reasonably Foreseeable Future Actions 

4.0 NEAR-FIELD MODELING 

A near-field ambient air quality impact analysis was performed to quantify the maximum criteria 

pollutant (PM10, PM2.5, CO, NO2, SO2, and Ozone [O3]) and HAP (benzene, toluene, 

ethylbenzene, xylenes, n-hexane, and formaldehyde) impacts that could occur within and near 

the Seminoe Road Project area. These impacts would result from emissions associated with 

construction and production activities, and the projected impacts are compared to applicable 

Seminoe Road Gas Development Project H-9 
Draft Environmental Impact Statement November 2005

ambient air quality standards and significance thresholds. Modeling analyses were performed in 

accordance with TRC 2004a. 

EPA's AERMOD model was used to assess near-field impacts of criteria pollutants PM10, PM2.5, 

CO, NO2 and SO2, and to estimate short-term and long-term HAP impacts. The AERMOD model 

utilizes the PRIME building downwash algorithms, which are the most recent “state of science” 

algorithms for modeling applications. One year of Rawlins meteorological data was used with the 

AERMOD dispersion model to assess these pollutant impacts. 

Ozone impacts were estimated using a screening methodology developed by Scheffe (1988) that 

utilizes NOX and VOC emissions ratios to calculate ozone concentrations. NOX and VOC 

emissions would typically be highest during production activities, and these emissions were used 

to estimate ozone impacts. 

4.1 Particulate Matter Near-Field Modeling Results 

Maximum localized PM10 and PM2.5 impacts would occur from well pad construction, access road 

construction, and wind erosion. The modeling scenario examined the construction of a 2.2-acre 

well site pad and two miles of access road per well pad. Model receptors were placed beginning 

200 meters from the edge of the well pad and road and at 50-meter intervals along the first row 

and at 100-meter intervals out to 1 kilometer. Flat terrain was assumed. 

Volume sources were used to represent emissions from well pads and access roads. Hourly 

emission rate adjustment factors were applied to account for daylight construction emissions, and 

modeling was conducted for the period of March 1 through October 31 to reflect an expected 

eight months of annual construction activities. 

Maximum predicted concentrations of PM10 and PM2.5 are presented in Table H-5, Maximum 

Modeled PM10 and PM2.5 Impacts. These modeled concentrations would be less than the 

Wyoming ambient air quality standards (WAAQS) and National ambient air quality standards 

(NAAQS) for PM10 and proposed standards for PM2.5, even after combined with representative 

background concentrations. 

H-10 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

Table H-5, Maximum Modeled PM10 and PM2.5 Impacts 

Pollutant Averaging 

Time 

Direct 

Modeled 

(Pg/m3

) 

Background 

(Pg/m3) 

Total 

Predicted 

(Pg/m3) 

WAAQS 

(Pg/m3) 

NAAQS 

(Pg/m3) 

PM10 

24-hour 20.4 33 53.4 150 150 

Annual 3.5 16 19.5 50 50 

PM2.5 

24-hour 7.1 13 20.1 65 65 

Annual 1.0 5 6.0 15 15 

4.2 SO2 Near-Field Modeling Results 

Maximum SO2 emission concentrations would occur during well drilling activities. The modeling 

scenario developed included a drilling rig at the center of the 2.2-acre well pad, with model 

receptors beginning 200 meters from the edge of the well pad at 50-meter intervals along the first 

row and at 100-meter intervals out to one kilometer. Drilling rigs were modeled as point sources. 

Maximum modeled SO2 emission concentrations are set forth in Table H-6, Maximum Modeled 

and SO2 Impacts. These modeled SO2 concentrations, even when added to representative 

background concentrations, are below applicable Federal and Wyoming standards. 

Table H-6, Maximum Modeled SO2 Impacts 

Pollutant Averaging 

Time 

Direct 

Modeled 

(Pg/m3

) 

Background 

(Pg/m3

) 

Total 

Predicted 

(Pg/m3

) 

WAAQS 

(Pg/m3

) 

NAAQS 

(Pg/m3) 

3-hour 15.4 132 147.4 1,300 1,300 

SO10 24-hour 7.6 43 50.6 260 365 

Annual 2.8 9 11.8 60 80 

4.3 NO2 and CO Near-Field Modeling Results 

Emissions from non-electrified production activities (well site pumps and compression facilities) 

would represent the maximum near-field NO2 concentrations. An analysis was performed to 

quantify the maximum NO2 impacts that could occur within and nearby the project area using the 

emissions from the non-electrified scenario. Proposed well emissions include those from downhole pumps and supply, gravel and work-over trucks. The three compressor stations were 

included. 

Seminoe Road Gas Development Project H-11 
Draft Environmental Impact Statement November 2005

NOX emissions provided for down-hole pumps and trucks were modeled using a single source 

polygon that spanned the entire project area. Receptors were placed throughout the project area 

at 1-kilometer intervals, increasing to 2-kilometers outside the project area boundary. 

Point sources were used to model the compressor station emissions. Refined receptor grids 

were placed around each of the three compressor stations, beginning 200 meters from the 

compressor station at 50-meter intervals along the compressor site perimeter and at 100-meter 

intervals from the compressor site perimeter outward to one kilometer. 

AERMAP was used to determine receptor height parameters from a 30-meter digitized elevation 

map (DEM) data. Aerodynamic building downwash parameters were considered for each 

compressor station. 

The AERMOD model was used to predict maximum NOX impacts for the modeled scenario. The 

maximum modeled concentrations occurred near the center of the project area. Maximum 

predicted NO2 concentrations were determined by multiplying maximum predicted NOX 

concentrations by 0.75 in accordance with EPA’s Tier 2 NOX to NO2 ambient ratio conversion 

method. 

The modeled NO2 concentrations for the Seminoe Road Project would be below the PSD Class II 

Increment for NO2. Even when combined with the representative background NO2 

concentrations, the ambient NO2 concentrations are below the applicable WAAQS and NAAQS. 

Maximum CO emissions would occur from the same production activities (well site pumps and 

compression facilities) that result in maximum NO2 impacts. Maximum CO modeled 

concentrations, when combined with representative background CO concentrations, remain 

below the applicable WAAQS and NAAQS. 

Maximum predicted NO2 and CO emission concentrations are presented in Table H-7, Maximum 

Modeled NO2 and CO Impacts. 

Table H-7, Maximum Modeled O3 Impacts 

Pollutant Averaging 

Time 

Direct 

Modeled 

(Pg/m3

) 

RPM 

Background 

(Pg/m3) 

Total 

Predicted 

(Pg/m3

) 

WAAQS 

(Pg/m3

) 

NAAQS 

(Pg/m3) 

Ozone 1-hour 21.0 62.6 83.6 235 235 

8-hourl 14.7 62.6 77.3 157 157 

H-12 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

5.0 FAR-FIELD/CUMULATIVE IMPACTS MODELING 

The purpose of the far-field analyses was to quantify potential air quality impacts on Class I and 

sensitive Class II areas from emissions of NOX, SO2, PM10, and PM2.5 expected to result from the 

development and operation of the Seminoe Road Project. As shown on Figure 20, Air Quality 

Modeling Domain, the modeling domain for the cumulative impact assessment included the 

following Class I and sensitive Class II areas: 

Bridger Wilderness Area (Class I); 

3⁄4 Fitzpatrick Wilderness Area (Class I); 

3⁄4 Popo Agie Wilderness Area (Class II); 

3⁄4 Wind River Roadless Area (Class II); 

3⁄4 Mount Zirkel Wilderness Area (Class I); 

3⁄4 Rawah Wilderness Area (Class I); 

3⁄4 Savage Run Wilderness Area (Federal Class II, Wyoming Class I); 

3⁄4 Rocky Mountain National Park (Class I); and 

3⁄4 Dinosaur National Monument (Federal Class II, Colorado Class I). 

Predicted pollutant concentrations at these sensitive areas were compared to applicable ambient 

air quality standards and PSD Class I and Class II increments and were used to assess potential 

impacts to the air quality related values (AQRV) of visibility (regional haze) and acid deposition. 

Potential lake acidification from acid deposition impacts was analyzed for the following 14 lakes 

designated as acid sensitive: 

3⁄4 Deep Lake in the Bridger Wilderness Area; 

3⁄4 Black Joe Lake in the Bridger Wilderness Area; 

3⁄4 Hobbs Lake in the Bridger Wilderness Area; 

3⁄4 Upper Frozen Lake in the Bridger Wilderness Area; 

3⁄4 Lazy Boy Lake in the Bridger Wilderness Area; 

3⁄4 Ross Lake in the Fitzpatrick Wilderness Area; 

3⁄4 Lower Saddlebag Lake in the Popo Agie Wilderness Area; 

Seminoe Road Gas Development Project H-13 
Draft Environmental Impact Statement November 2005

3⁄4 West Glacier Lake in the Glacier Lakes Ecosystem Experiments Site (GLEES); 

3⁄4 Lake Elbert in the Mount Zirkel Wilderness Area; 

3⁄4 Seven Lakes in the Mount Zirkel Wilderness Area; 

3⁄4 Summit Lake in the Mount Zirkel Wilderness Area; 

3⁄4 Island Lake in the Rawah Wilderness Area; 

3⁄4 Kelly Lake in the Rawah Wilderness Area; and 

3⁄4 Rawah Lake #4 in the Rawah Wilderness Area. 

5.1 Modeling Methodology 

The EPA-approved CALMET/CALPUFF modeling system (CALMET Version 5.53, Level 030709, 

and CALPUFF Version 5.711, Level 030625) was used for the far-field cumulative modeling 

analyses. The CALMET meteorological model used wind fields developed from 1995 

meteorological data, and the CALPUFF dispersion model combined these wind fields with 

project-specific and regional emissions inventories of SO2, NOX, PM10, and PM2.5 to estimate 

ambient concentrations and AQRV impacts at in-field and far-field receptor locations. 

The CALMET and CALPUFF models follow the methods described in TRC 20004a and the 

following standard guidance sources: 

3⁄4 Guideline on Air Quality Models, 40 CFR, Part 51, Appendix W; 

3⁄4 Interagency Work Group on Air Quality Modeling Phase 2 Summary Report and 

Recommendations for Modeling Long Range Transport Impacts, EPA-454/R-98-019, 

Office of Air Quality Planning and Standards, December 1998; and, 

3⁄4 Federal Land Managers - Air Quality Related Values Workgroup (FLAG), Phase I Report, 

December 2000. 

The CALMET wind fields developed for this analysis follow the CALMET methodologies 

established as part of the Southwest Wyoming Technical Air Forum for southwest Wyoming, and 

were further enhanced through the use of additional meteorological data sets and revised 

CALMET model code. 

H-14 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

5.2 Project Modeling Scenarios 

Modeling scenarios were developed for the electrified proposed action and a non-electrified 

scenario. The modeled proposed action scenario included 26 wells outside the electrification 

zone and one non-electrified compressor facility. The non-electrification scenario modeled 

assumed that well pumps and compressor facilities would be powered by natural gas. 

Maximum field-wide emissions reflect the last year of field development for both scenarios, which 

show 1,040 wells in production and 200 wells being drilled and developed by six drilling rigs. 

Compression for both scenarios was assumed at 90% of permitted capacity. The modeled 

emissions for these two scenarios are shown in Table H-8, Maximum Emissions. 

Table H-8, Maximum Emissions (tons/year) 

Project Phase/Constituent Proposed Action Non-Electrification Scenario 

Production Well

1 

NOx 5.1 205.9 

SO2 0.0 0.0 

PM10 0.0 0.0 

PM2.5 0.0 0.0 

Production Traffic2 

NOx 0.3 0.3 

SO2 0.01 0.01 

PM10 295.6 295.6 

PM2.5 44.2 44.2 

Compression3 

NOx 34.7 104.2 

SO2 0.0 0.0 

PM10 0.0 0.0 

PM2.5 0.0 0.0 

Construction4 

NOx 300.1 300.1 

SO2 31.9 31.9 

PM10 70.7 70.7 

PM2.5 39.7 39.7 

Total 

NOx 340.2 610.5 

SO2 31.9 31.9 

PM10 366.3 366.3 

PM2.5 83.9 83.9 

Notes: 

(1) Includes emissions from well site down-hole water pump engines. 

(2) Includes emissions from all traffic associated with 1040 wells in production. 

(3) Includes emissions from the proposed compressor stations. 

(4) Includes emissions associated with 6 drilling rigs, 2 under construction (rig-up/rig-down), 4 

operating continuously. 

Seminoe Road Gas Development Project H-15 
Draft Environmental Impact Statement November 2005

5.3 Meteorological Model Input And Options 

CALMET was used to develop wind fields for the model domain (TRC 2004a). Model domain 

extent was selected based on available refined mesoscale meteorological model (MM5) data 

from the Southwest Wyoming Technical Air Forum study and the locations of the PSD Class I and 

sensitive Class II wilderness areas within the modeling domain. 

The modeling domain was processed to a uniform horizontal grid using a 4-kilometer resolution 

based on a Lambert Conformal Projection defined with a central longitude/latitude at 

(-108.55°/42.55°) and first and second latitude parallels at 30° and 60°. The modeling grid 

consisted of 125 x 100, 4-kilometer grid cells, and covered the Seminoe Road project area and l 

analyzed Class I and sensitive Class II areas. The total area of the modeling domain was 500 x 

400 kilometers. Ten vertical layers were used, with heights of 20, 40, 100, 140, 320, 580, 1,020, 

1,480, 2,220, and 2,980 meters. 

The CALMET analysis utilized the MM5 data (processed at a 20-kilometer horizontal grid 

spacing), data from 51 surface meteorological stations and 134 precipitation stations, and four 

upper air meteorological stations to supplement MM5 upper air estimates. USGS 

1:250,000-Scale Land Use and Land Cover (LULC) data, and USGS 1-degree DEM data were 

used for land use and terrain data in the development of the CALMET wind fields. The CALMET 

model was run following control switch settings that were developed as part of SWWYTAF to 

develop the one-year (1995) wind field data set. 

The modeling domain extended as far south and east as possible given the available refined 

MM5 data. The Interagency Work Group on Air Quality Modeling (IWAQM) guidance for 

CALMET/CALPUFF recommends that the horizontal domain of a model grid extend 50 to 80 

kilometers beyond the receptors and sources being modeled to ensure potential re-circulation 

wind flow effects are properly modeled. The re-circulation wind patterns may not be completely 

resolved by CALMET for the generated wind field in the southern and eastern portions of the 

Rocky Mountain National Park area because this area is less than 50 kilometers from the 

modeling grid boundary. However, the potential impacts from the Seminoe Road Project would 

be appropriately assessed because the direct wind flow patterns that could transport potential 

project (and other regional) emissions to the Rocky Mountain National Park are properly 

characterized in the modeling domain. 

H-16 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

5.4 Dispersion Model Input And Options 

The CALPUFF model was used to model project-specific and regional emissions of NOX, SO2, 

PM10, and PM2.5 (TRC 2004a). 

CALPUFF was run using the IWAQM-recommended default control file switch settings for all 

parameters. Chemical transformations were modeled based on the MESOPUFF II chemistry 

mechanism for conversion of SO2 to sulfate (SO4) and NOX to nitric acid (HNO3) and nitrate 

(NO3). Each of these pollutant species was included in the CALPUFF model runs. 

NOX, HNO3, and SO2 were modeled with gaseous deposition, and SO4, NO3, PM10, and PM2.5 

were modeled using particle deposition. The PM10 emissions input to CALPUFF included only 

the PM10 emissions greater than the PM2.5 (i.e., modeled PM10 = PM10 emission rate – PM2.5 

emission rate). Total PM10 impacts were determined in the post-processing of modeled impacts. 

5.4.1 Chemical Species 

The CALPUFF chemistry algorithms require hourly estimates of background ozone and ammonia 

concentrations to predict the conversion of SO2 and NO/NO2 to sulfates and nitrates, respectively. 

Background ozone data for the 1995 meteorological data year were available for six stations 

within the modeling domain: 

3⁄4 Pinedale, Wyoming, 

3⁄4 Centennial, Wyoming, 

3⁄4 Yellowstone National Park, Wyoming, 

3⁄4 Craters of the Moon National Park, Idaho, 

3⁄4 Highland, Utah, and 

3⁄4 Mount Zirkel Visibility Study, Hayden, Colorado. 

Hourly ozone data from these stations were used in the CALPUFF modeling, with a default value 

of 44.7 parts per billion (ppb) (7 a.m.-7 p.m. mean) used for missing hours. A background 

ammonia concentration of 1.0 ppb was used as suggested in the IWAQM guidance for arid lands. 

5.4.2 Model Receptors 

CALPUFF model receptors, at which the concentration, deposition, and AQRV impacts were 

calculated, were defined along the boundaries of Class I and other sensitive areas at a 2­

Seminoe Road Gas Development Project H-17 
Draft Environmental Impact Statement November 2005

kilometer spacing and within the boundaries of these areas on a 4-kilometer Cartesian grid. 

Discrete receptors were placed on a Cartesian grid at a 4-kilometer spacing within the Seminoe 

Road Project area. Individual receptor points were defined at each of the 14 acid-sensitive lakes. 

Receptor elevations for Class I and sensitive Class II areas were determined from 1:250,000 

scale USGS DEM data. Elevations for the sensitive lake receptors were derived from 7.5-minute 

USGS topographical maps. 

5.4.3 Source Parameters 

CALPUFF source parameters were determined for project and regional source emissions of NOX, 

SO2, PM10, and PM2.5 (TRC 2004a). Project sources were input to CALPUFF using point sources 

to idealize compressor stations, drilling rigs, pit flares, and down-hole well pump engines. 

Additionally, 4-kilometer-square area sources at a 4-kilometer spacing were placed throughout 

the project area to idealize vehicle traffic, wind erosion and down-hole well pump emissions. 

Non-project regional emissions were input to CALPUFF using area sources to idealize 

non-compression RFD sources and countywide well sites; and point sources to idealize 

state-permitted, RFD compression, and RFFA sources. Non-compression RFD emissions were 

modeled using area sources developed for each proposed field development as a best fit to the 

respective project area. Countywide well emissions were modeled using area sources that best 

fit the respective county area. 

5.5 Criteria Pollutant Background Data 

Ambient air concentration data collected at regional monitoring sites provided the measure of the 

background conditions during the most recent available time period. Regional monitoring-based 

background values for criteria pollutants (PM10, PM2.5, NO2, and SO2) were collected at 

monitoring sites in Wyoming and northwestern Colorado and are summarized in Table H-9, Farfield Analysis Background of Ambient Air Quality Concentrations. These ambient air 

background concentrations are added to modeled pollutant impacts to yield total predicted 

ambient air quality concentrations for comparison to applicable ambient air quality standards. 

H-18 Seminoe Road Gas Development Project 
3

Draft Environmental Impact Statement November 2005

Table H-9, Far-Field Analysis Background of Ambient Air Quality Concentrations (μg/m )


Pollutant Averaging Period Measured Background Concentration 

Nitrogen dioxide (NO2)

1 Annual 3.4 

PM10 

2 24-hour 

Annual 

33 

16 

PM2.5 

2 24-hour 

Annual 

13 

5 

Sulfur dioxide (SO2)

3 3-hour 

24-hour 

Annual 

132 

43 

9 

Notes: 

(1) Data collected at Green River Basin Visibility Study site, Green River, Wyoming during period JanuaryDecember 2001 (ARS 2002). 

(2) Data collected by WDEQ-AQD at Emerson Building, Cheyenne, Wyoming, Year 2001. 

(3) Data collected at LaBarge Study Area at the Northwest Pipeline Craven Creek Site 1982-1983. 

5.6 Visibility Background Data 

Background visibility data were obtained from IMPROVE monitoring sites located at the Bridger 

Wilderness Area, the Mount Zirkel Wilderness Area, and the Rocky Mountain National Park. See 

Table H-10, IMPROVE Background Aerosol Extinction Values. Background visibility data are 

used in combination with modeled pollutant impacts to estimate change in visibility conditions that 

is measured as change in light extinction. The IMPROVE background visibility data are provided 

as reconstructed aerosol total extinction data based on the quarterly mean of the 20 percent 

cleanest days measured at each site for the historical monitoring period of record through 

December 2002. 

Table H-10, IMPROVE Background Aerosol Extinction Values 

IMPROVE Site Quarter Hygroscopic 

(Mm-1

) 

Non-Hygroscopic 

(Mm-1) Monitoring Period 

1 0.845 1.666 1989-2002 

Bridger Wilderness Area 2 1.730 3.800 1988-2002 

3 1.902 5.637 1988-2002 

4 0.915 2.035 1988-2002 

1 1.269 2.591 1995-2002 

Mount Zirkel Wilderness Area 2 2.028 4.163 1995-2002 

3 2.358 5.151 1994-2002 

4 0.961 2.262 1994-2002 

1 0.986 2.117 1991-2002 

Rocky Mountain National Park 2 2.457 5.261 1991-2002 

3 2.651 6.709 1991-2002 

4 0.790 2.720 1990-2002 

Seminoe Road Gas Development Project H-19 
Draft Environmental Impact Statement November 2005

5.7 Lake Chemistry Background Data 

The most recent lake chemistry background ANC data were obtained for each sensitive lake. 

The 10th percentile lowest ANC values were calculated for each lake following procedures 

provided by the Forest Service. These ANC values and the number of samples used in the 

calculation of the 10th percentile lowest ANC values are provided in Table H-11, Background 

ANC Values for Acid Sensitive Lakes. 

Table H-11, Background ANC Values for Acid Sensitive Lakes 

Wilderness 

Area Lake Latitude 

(Deg-Min-Sec) 

Longitude 

(Deg-Min-Sec) 

10th Percentile 

Lowest ANC 

Value 

(μeq/l) 

Number of 

Samples 

Monitoring 

Period 

Bridger Black Joe 42o44'22" 109o10'16" 67.0 61 1984-2003 

Bridger Deep 42o43'10" 109o10'15" 59.9 58 1984-2003 

Bridger Hobbs 43o02'08" 109o40'20" 69.9 65 1984-2003 

Bridger Lazy Boy 43o19'57" 109o43'47" 18.8 1 1997 

Bridger Upper Frozen 42o41'13" 109o09'39" 5.0 6 1997-2003 

Fitzpatrick Ross 43o22'41" 109o39'30" 53.5 44 1988-2003 

GLEES(1) West Glacier Lake 41o22'38" 106o15'31" 35.2 14 1988-1996 

Mount Zirkel Lake Elbert 40o38'3" 106o42'25" 51.9 55 1985-2003 

Mount Zirkel Seven Lakes 40o53'45" 106o40'55" 36.2 55 1985-2003 

Mount Zirkel Summit Lake 40o32'43" 106o40'55" 47.3 95 1985-2003 

Popo Agie Lower Saddlebag 42o37'24" 108o59'38" 55.5 43 1989-2003 

Rawah Island Lake 40o37'38" 105o56'26" 68.7 15 1996-2002 

Rawah Kelly Lake 40o37'32" 105o57'34" 181.1 13 1995-2002 

Rawah Rawah Lake #4 4040'16" 105o57'28" 41.2 13 1996-2002 

Note: 

(1) GLEES (Glacier Lakes Ecosystem Experiments Site) – Medicine Bow National Forest, Snowy Range, 

Wyoming. 

5.8 Impact Assessment 

ALPUFF modeling was performed to compute direct and cumulative impacts from the Seminoe 

Road Project and regional sources. 

CALPUFF-modeled concentration impacts were post-processed with POSTUTIL and CALPOST 

for each far-field sensitive area to derive: 

3⁄4 Concentrations for comparison to ambient standards (WAAQS and NAAQS), PSD Class I 

significance thresholds, and PSD Class I and II Increments; 

3⁄4 Deposition rates for comparison to sulfur (S) and nitrogen (N) deposition thresholds and 

to calculate changes to acid neutralizing capacity (ANC) at sensitive lakes; and 

H-20 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

3⁄4 Light extinction changes for comparison to visibility impact thresholds. For in-field 

locations, CALPUFF concentrations were post-processed to compute maximum 

concentration impacts for comparison to WAAQS and NAAQS. 

5.8.1 Concentration 

The CALPOST and POSTUTIL post-processors were used to summarize concentration impacts 

of NO2, SO2, PM10, and PM2.5 at PSD Class I and sensitive PSD Class II areas, and at in-field 

locations. Predicted impacts are compared to applicable ambient air quality standards, PSD 

Class I and Class II increments, and significance levels. 

PM10 concentrations were computed by adding predicted CALPUFF concentrations of PM10, 

PM2.5, SO4, and NO3. PM2.5 concentrations were calculated as the sum of modeled PM2.5, SO4, 

and NO3 concentrations. The PM10 impacts from project-related traffic emissions (production and 

construction) were not included when post-processing the PM10 impacts at all far-field receptor 

locations, only the PM2.5 impacts were considered. This assumption was based on supporting 

documentation from the Western Regional Air Partnership (WRAP) analyses of mechanically 

generated fugitive dust emissions that suggest that particles larger than PM2.5 tend to deposit out 

rapidly near the emissions source and do not transport over long distances (TRC 2004b). This 

phenomenon is not modeled adequately by CALPUFF. Therefore, these sources were not 

considered in the total modeled impacts to avoid overestimating PM10 impacts at far-field 

locations. The total PM10 impacts from traffic emissions were included in the in-field 

concentration modeling. 

Far-Field Results. The modeling indicates that the Seminoe Road Project would cause and 

direct or cumulative impacts above any federal or state air quality standards or established PSD 

increments, and such impacts would be below the proposed PSD Class I significant impact levels 

at the evaluated Class I areas (TRC 2004b). 

In-Field Results. The modeling of the Seminoe Road Project shows that there would be no 

exceedences of air quality standards within and nearby the project Area from project construction 

and production activities. 

Seminoe Road Gas Development Project H-21 
Draft Environmental Impact Statement November 2005

5.8.2 Deposition 

Sulfur (S) and nitrogen (N) deposition impacts were modeled. The POSTUTIL utility was used to 

estimate total S and N fluxes from CALPUFF predicted wet and dry fluxes of SO2, SO4, NOX, 

NO3, and HNO3. CALPOST summarized the annual S and N deposition values from the 

POSTUTIL program. Predicted Seminoe Road Project direct impacts were compared to the NPS 

deposition analysis thresholds (DAT) for total N and S deposition in the western U.S., which are 

defined as 0.005 kilograms per hectare per year (kg/ha-year) for both elements. 

Modeling results indicated that there would be no direct project N or S deposition impacts above 

the DAT and that cumulative N and S deposition impacts would be well below the cumulative 

analysis thresholds. Further, there would be no adverse impacts from acid deposition as 

modeled results were well below Forest Service thresholds, defined as 5 kg/ha-yr for S and 3 

kg/ha-yr for N (TRC 2004b). 

5.8.3 Sensitive Lakes 

The modeling indicates that direct and cumulative deposition impacts from the Seminoe Road 

Project would not contribute significantly to an increase in acidification at any of the sensitive 

lakes (TRC 2004b). 

The CALPUFF-predicted annual deposition fluxes of S and N at sensitive lake receptors were 

used to estimate the change in ANC. The change in ANC was calculated following the January 

2000, Forest Service Rocky Mountain Region's Screening Methodology for Calculating ANC 

Change to High Elevation Lakes, User's Guide. The predicted changes in ANC were compared 

with the Forest Service's Level of Acceptable Change (LAC) thresholds of 10 percent for lakes 

with ANC values greater than 25 microequivalents per liter (μeq/l) and 1 μeq/l for lakes with 

background ANC values of 25 μeq/l or less. 

5.8.4 Visibility 

The CALPUFF model-predicted concentration impacts at far-field PSD Class I and sensitive 

Class II areas were post-processed with the CALPOST model to estimate potential impacts to 

visibility (regional haze) for both the electrified and non-electrified scenarios. 

The CALPOST model was used to estimate visibility impacts from predicted concentrations of 

PM10, PM2.5, SO4, and NO3. Similar to post-processing far-field PM10 concentration impacts, 

H-22 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

PM10 impacts from project-related traffic emissions were not included in the total estimated 

impacts. Only PM2.5 impacts were considered. 

Background Conditions. Visibility impairment calculations were performed using estimated 

natural background visibility conditions and measured background visibility conditions from the 

Bridger Wilderness Area, the Mount Zirkel Wilderness Area, and Rocky Mountain National Park 

IMPROVE sites (TRC 2004b). 

The IMPROVE background visibility data are provided as reconstructed aerosol total extinction 

data, based on the quarterly mean of the 20 percent cleanest days measured at each site for the 

historical monitoring period of record through December 2002. 

The natural background visibility data used with the FLAG visibility analysis are shown in Table 

H-12, FLAG Report Background Extinction Values. 

Table H-12, FLAG Report Background Extinction Values 

Season Hygroscopic 

(Mm-1

) 

Non-hygroscopic 

(Mm-1) 

Winter 0.6 4.5 

Spring 0.6 4.5 

Summer 0.6 4.5 

Fall 0.6 4.5 

Note: 

(1) Federal Land Managers’ Air 

December 2000. 

Quality Related Values Workgroup (FLAG) Phase I Report, 

The IMPROVE method used EPA-provided monthly relative humidity factors (TRC 2004b). See 

Table H-13, Monthly Relative Humidity Factors From IMPROVE Sites. 

Change in atmospheric light extinction relative to background conditions is used to measure 

regional haze. Analysis thresholds for atmospheric light extinction are reported in percent change 

in light extinction and change in deciview (dv). The thresholds are defined as 5 percent and 10 

percent of the reference background visibility or 0.5-dv and 1.0-dv for project and cumulative 

source impacts, respectively. The BLM considers a 1.0-dv change as a significant adverse 

impact. It should be noted that there are no applicable local, state, tribal, or federal regulatory 

visibility standards. 

Seminoe Road Gas Development Project H-23 
Draft Environmental Impact Statement November 2005

Table H-13, Monthly Relative Humidity Factors From IMPROVE Sites


IMPROVE Site Quarter Months f(RH) Values 

Bridger Wilderness Area1 

1 Jan, Feb, Mar 2.5, 2.3, 2.3 

2 Apr, May, Jun 2.1, 2.1, 1.8 

3 Jul, Aug, Sep 1.5, 1.5, 1.8 

4 Oct, Nov, Dec 2.0, 2.5, 2.4 

Mount Zirkel Wilderness Area2 

1 Jan, Feb, Mar 2.2, 2.2, 2.0 

2 Apr, May, Jun 2.1, 2.2, 1.8 

3 Jul, Aug, Sep 1.7, 1.8, 2.0 

4 Oct, Nov, Dec 1.9, 2.1, 2.1 

Rocky Mountain National Park 

1 Jan, Feb, Mar 1.9, 2.0, 2.0 

2 Apr, May, Jun 2.1, 2.3, 2.0 

3 Jul, Aug, Sep 1.9, 1.9, 2.0 

4 Oct, Nov, Dec 1.8, 2.0, 1.9 

Notes: 

(1) Also used for Fitzpatrick and Popo Agie Wilderness Areas, and Wind River Roadless Area. 

(2) Also used for Rawah and Savage Run Wilderness Areas, and Dinosaur National Monument. 

Far-Field Results. Using both the FLAG and IMPROVE background visibility data, direct 

visibility impacts from Seminoe Road Project sources were predicted to be below 0.5-dv. 

However, the cumulative modeled results (encompassing the Atlantic Rim Project, the Seminoe 

Road Project, and other regional sources) revealed that the BLM 1.0-dv significance threshold 

could be exceeded for a few days each year at the Bridger, Popo Agie, and Wind River 

Wilderness areas. The highest predicted impact would occur at the Bridger Wilderness, where it 

was modeled that the BLM 1.0-dv threshold could be exceeded on four days per year (using 

IMPROVE data) but only one day per year (using FLAG data). The maximum deciview change 

at the Bridger Wilderness Area was estimated as 2.1 dv (Using IMPROVE data) and 1.8 dv (using 

FLAG data) (TRC 2004b). 

The FLAG report defines a 0.4 percent change in extinction (0.04 dv) to be a project-specific 

significance level for cumulative visibility analyses. As such, a project is regarded as having an 

insignificant contribution to a cumulative visibility impact if that project contribution to a cumulative 

visibility impact of 1.0 dv is less than 0.04 dv. Using these criteria, an analysis was performed for 

all days when estimated cumulative visibility impacts for sensitive receptor areas were predicted 

to be at or above the BLM 1.0-dv significance threshold. The results of this analysis showed that 

Seminoe Road Project impacts were below the 0.04-dv visibility threshold for all days when the 

cumulative visibility impacts were predicted to be 1.0 dv or greater (TRC 2004b). Thus, it was 

H-24 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

concluded that the Seminoe Road Project would not contribute to any significant visibility impacts 

to any of the Class I or sensitive Class II PSD areas in the region. 

Seminoe Road Gas Development Project H-25 
Appendix I 

Monitoring Results for the 

Seminoe Road Pilot Project 
Monitoring Results for the Seminoe Road Pilot Project


Bob Lange - November 14, 2005 


I. Introduction: 

This appendix details monitoring data collected for the Seminoe Road Pilot Project by the BLM. 

Data included cross-sections to look at channel erosion in Pool Table Draw, water quality 

sampling in Pool Table Draw and a shallow groundwater well cluster below the stock pond in 

Pool Table Draw. 

Monitoring of the Pilot Project has shown that continuous discharge of water into ephemeral 

channels near Seminoe Reservoir results in channel incision and lateral adjustment producing 

channel erosion significantly above undisturbed conditions. Further, water quality changes and 

conveyance loss is minimal to water moving down drainages and appears to be seasonally 

dependent and the shallow groundwater in the alluvium below the reservoir on Pool Table Draw 

is connected to reservoir waters. 

II. Channel Erosion in Pool Table Draw 

An “ephemeral drainage” means a drainage that flows only in direct response to precipitation in 

the immediate watershed or in response to melting of a cover of snow or ice, and a drainage, 

which has a channel bottom that is nearly always above the local water table. The EIS analysis 

area includes ten main ephemeral drainages that are being considered as potential discharge 

drainages for Seminoe Road Project produced water. 

Ephemeral drainage channels dry out between storm events, which reduces infiltration and 

increases surface runoff along the bottom of the channels. Sediment moves in pulses with these 

storm events resulting in wide channel forms with fine textured bed deposited material. Due to 

the dry soils in these channel bottoms water predominantly moves as sheet flow or in macropores 

created by preferential erosion and/or animal burrows. Abrupt changes in surface water flows 

due to surface roughness from vegetation (sagebrush, greasewood, and grasses), the channel 

gradient, and/or preferential channels form in features like animal trails cause surface water to 

concentrate and velocities to increase. This process can increase the erosive energy of the water 

during storm events. 

These flood events are usually short lived since a typical summer thunderstorm last less than 

several hours. The majority of the water in these systems moves quickly through the drainage in 

flash floods and storm pulses that are only attenuated based on the travel time of the water 

(Figure 4). 

Ephemeral channels are susceptible to erosion in the drainage channel bed, called “headcuts”. 

Erosion potential was evaluated during baseline data collection efforts. A headcut is an abrupt 

vertical drop in a channel that is a result of the breakdown of soil structure or an increase in flow 

concentration or velocity. Erosion can continue in the channel below a headcut causing a gulley 

to form, and can cause the channel to be incised deeper than before, a process called downcutting. The abrupt change in elevation over the headcut increases the erosive energy of the 

water and can allow the headcut to migrate upstream. 
The channel erosion (one headcut beginning the pool of the reservoir, and the other a nick point 

or nick points that have extended up past the high pool level for the reservoir) were first observed 

in 2001. These erosional features have steadily extended up the drainage and can be grouped into 

three types of features. Farthest upstream is a series of nick points that are typically 1 foot or less 

in elevation drop (Map 1), at about XS-2 a significant vertical adjustment takes place to a 

severely incised channel 3 to 5 feet deep and 1 foot wide, and finally to a widening gulley driven 

by bank slumping due to undercutting by the channel that is 5-15 feet deep and 3 to 20 feet wide 

(Figure 1). 

Figure 1: Pictures of headcut during the first two years (2001-2002). The picture on the left shows the 

change in velocity that down cuts the headcut and allows it to migrate upstream with small disharges. After 

the initial vertical adjustment the headcut widens with bank sluffing shown on the right. Note the current 

position of the headcut is in the sagebrush shown in the background.

Riprap was placed in the channel in 2002 in an attempt to reduce the erosional energy at the 

location of the downstream headcut and was unsuccessful as shown in the Figure 2. Figure 2 was 

taken the winter after the rip-rap was installed and shows one section of the rip-rap channel 

undercut by flows. In the background, two piles of riprap can be seen that had not yet been 

installed. 

Figure 2: Riprap in Channel

In January of 2003, the BLM established three cross-sections (XSs) upstream of the high 

pool line of the reservoir (Map 1). 

Map 1: Cross-sections and Current Locations for Headcut Features.

Data from these cross-sections show that the headcut (the narrow incised portion) moved through 

XS-4 in the months after the storm event on 8/16/03. The headcut did not cut through XS-4 

during the storm event, but did so after (Figure 3). The data also shows a consistent increase in 

depth, cutting 1/3 ft. deeper from 8/24/04 to 9/15/04 during periods of moderate rainfall. 

The channel sides in the vicinity of XS-4 are beginning to be undercut and it can be anticipated to 

result in a wider channel similar to what occurs just below XS-4. The headcut is fast approaching 

XS-3, and the highest nick point is just beyond XS-3. These facts support the opinion that the 

continuous discharge from the project provides the energy for the vertical adjustment, which 

contributes to the later widening of the channel. 
8/26/04 

8/28/04 8/30/04 

9/1/04 9/3/04 9/5/04 9/7/04 9/9/04 

9/11/04 

9/13/04 9/15/04 

Cross Section Comparison 

0 

5 

10 

50 55 60 65 70 

Distance (ft) 

(From Left Bank to Right Bank, Facing Upstream) 

Elevation (ft) 

1/29/2003 8/26/2003 8/12/2004 9/15/2004 

Inches 

Daily Precipitation 

0.40 

0.35 

0.30 

0.25 

0.20 

0.15 

0.10 

0.05 

0.00 

Date 

Figure 3: Cross-section 4 Measurements and precipitation from 8/26-9/15/2004.

Empirical methods used to calculate peak storm are notoriously inaccurate for ephemeral 

systems. This is because the equations are based on relationships calculated from perennial 

gaged watersheds. The USGS released, “Peak-Flow Characteristics of Wyoming Streams, Report 

03-4107” in 2003. Using this method the 2 year storm event is estimated to be 53 cfs and the 

95% confidence interval around this value would be 15 cfs and 182 cfs (Figure 4). 

The flood event in August 2003 was photographed and the flows can be estimated at XS-4 using 

the Mannings equation (Figure 4). As can be seen from Figure 4 the terrace had overland flow 

during the storm event. Using the elevations from 8/26/03 and assuming the high elevation of the 

water was 3.5 feet above the channel bottom and an average of 0.5 ft above the terrace (much 

higher than what is shown in the photograph), the peak would conservatively be under 82 cfs. 

Return 

Interval 

Flow 

(cfs) 

95% Confidence 

Lower 

Limit 

Higher 

Limit 

Q1.5 = 33 9 125 

Q2 = 53 15 182 

Q2.33 = 65 19 215 

Q5 = 131 43 399 
Seminoe XS-4 Cross Section Profile 

0 

3 

6 

9 

12 

0 20 40 60 80 100 120 

Distance (ft) 

(From Left Bank to Right Bank, Facing Upstream) 

Elevation (ft) 

Elev. (ft) Storm Event 

Figure 4: Flood Event Downstream of XS-4, XS-4 and Storm Events using Miller, 2003.

The original water management plan used accepted methods at the time (Lowham, 1976 and 

Craig and Rankl, 1978), however with the new USGS method (Figure 4) estimates much lower 

flows for the peak events. As can be seen from the large range between the 95% confidence 

intervals these flows are still only estimate. The storm event in August 2003 was probably about 

a 5 year event and not entirely uncommon in this drainage. In itself this or other storm events 

don’t last long enough to trigger the types of vertical adjustment in the channels witnessed. This 

point is further substantiated by cross-sectional data collect that show a fairly consistent 

downcutting with typical precipitation. 

Monitoring of these sites has shown consistent movement of active headcutting upstream from 

the locations observed in early 2003. The process is vertical adjustment via a series of knick 

points that eventually form a narrow trench for the channel. This narrow trench with steep sides 

is then widened due to bank slumping and piping. The final state is a gulley detached from the 

flood-plane with very few lateral features to reduce erosional energy (figure 1). 

III. Water Quality Sampling 

Two channel sampling trips were implemented, one in 12/6/2003 and the other in 8/04/2004. 

The water quality data collected on December 6, 2003 showed that the discharged water was not 

changing significantly as it moves down the channel during the winter months. This relationship 

may change in other seasons. This can be seen from comparing site XS-1 and XS-2 and also by 

comparing XS-3 and XS-4 with TDS. There is a 19 mg/L increase between 1 and a decrease of 

40 mg/L from 3 to 4. Iron shows a similar response, except showing a minor increase between 1 

and a slight decrease between 3 and 4. Other parameters show a similar pattern, i.e. not changing 

very much as the water moves down the channel. 
Table 1: Summary Field Data for All Cross Sections


XS # Discharge 

12/3/03 (cfs) 

Discharge 

8/4/04 (cfs) 

Dissolved 

Iron 

12/3/03 

(mg/L) 

Dissolved 

Iron 8/4/04 

(mg/L) 

Dissolved 

Manganese 

12/3/03 (mg/L) 

Dissolved 

Manganese 

8/4/04 (mg/L) 

XS1 0.40 0.12 0.95 0.94 0.020 0.040 

XS2 0.40 0.11 0.92 1.35 0.020 0.040 

EF 0.76 0.60 0.79 0.15 0.040 0.010 

XS3 1.04 0.72 0.84 0.03 0.010 0.010 

XS4 1.02 0.87 0.84 0.28 0.030 0.010 

Dissolved Iron Concentrations along Pool Table Draw 

-10% 

0% 

10% 

20% 

30% 

40% 

50% 

60% 

Above Confluence Below Confluence 

XS1-XS2 XS3-XS4 

Reach Locations 

Dissolved Iron/ % 

Change 

U

pstream to 

D

o

wnstream 

Iron 12/6/2003 

Iron 8/12/2004 

Figure 5: Iron Concentration Changes in Channel Reaches, Represents the Difference between an 

Upstream and Downstream Site. 

Figure 5 shows the change between two locations on two different reaches. Notice that the iron 

concentrations changed significantly in August, but not in December. 
Appendix J 

Overview of Surface Water Mixing Model 
Draft Environmental Impact Statement November 2005

Appendix J – Overview of Surface Water Mixing Model

A surface-water mixing model (Mixing Model) was prepared to evaluate the potential impacts of 

the Seminoe Road Project action alternatives. The Mixing Model was based on a geochemical 

model developed by the EPA for the Powder River Basin EIS (BLM, 2003). The Mixing Model 

differs from the EPA model as it was designed to fit the site-specific conditions of the Seminoe 

Road Project and to determine the potential effects of releasing produced water into the North 

Platter River and Seminoe Reservoir. The Mixing Model estimates the mixed concentrations of 

sodium, calcium, and magnesium for the calculation of the sodium absorption ratio (SAR), as well 

as the mixed specific conductivity (a measure of overall salinity). The Mixing Model was 

designed to estimate the potential effect of project discharge on the quality of the North Platte 

River system water for irrigation purposes and to show general changes in overall water quality. 

No other constituents were considered for the modeling. A surface-water mixing model is 

illustrated in Figure 42, Diagram of a Surface Water Mixing Model. 

The Mixing Model utilizes conservative assumptions and the model results likely over-estimate 

potential surface water quality effects. As stated previously, the model was designed to 

qualitatively compare the potential effects of the various action alternatives. The model results 

provide numeric values, but these values should only be used to compare relative differences 

between project action alternatives. The assumptions used for the modeling include: 

x Inflows into Seminoe Reservoir for each month are equal to the average historical inflows 

for that month. 

x Water volume in Seminoe Reservoir is constant on an annual basis, i.e. the water volume 

changes month to month, but is constant for any 12-month period. 

x Seminoe Road Project discharge water will not increase the reservoir volume or


evaporation, but only increase outflow.


x Existing baseline water quality in the North Platte River above Seminoe Reservoir and in 

Seminoe Reservoir is assumed to be constant during low and high flow. 

Seminoe Road Gas Development Project J-1 
Draft Environmental Impact Statement July 2005

x Evapo-concentration does not play a significant role in changing the water quality in 

Seminoe Reservoir. 

x Water quality of the Seminoe Road Project produced water is similar to water quality of 

the Pilot Project and does not change between the discharge points and the receiving 

waters of the North Platte River or Seminoe Reservoir. 

x All constituents calculated behave conservatively, i.e. do not undergo chemical reactions 

or adsorption. 

To approximate the mixing effects as they occur along the North Platte River and in Seminoe 

Reservoir, the Mixing Model provided results for the following six locations: 

x Location 1 is in the North Platte River, below Dirtyman Draw. The flow in the North Platte 

River and discharge from discharge points DS-6, DS-7, and DS-18 are combined. 

x Location 2 is in Upper Seminoe Reservoir. The flow mixes with discharge from discharge 

points DS-8, DS-13, and DS-14 and with 16% of the total Seminoe Reservoir volume. 

x Location 3 is in Upper Middle Seminoe Reservoir. The flow mixes with discharge from 

discharge points DS-5, DS-9 and DS-12, and with 20% of reservoir volume. 

x Location 4 is in Middle Seminoe Reservoir. The flow mixes with discharge from 

discharge points DS-2, DS-3, DS-4, DS-10 and DS-11 and 34% of reservoir volume. 

Additional inflows enter Seminoe Reservoir at this location from the Medicine Bow River 

and O’Brien Creek. It was assumed that all inflows not attributable to the North Platter 

River would enter the reservoir at this location. Outflow from Location 4 mixes with 30% 

of Seminoe Reservoir volume. 

x Location 5 is in Lower Seminoe Reservoir at the dam and has no additional inflows from 

either discharge or tributary streams. Outflow from Seminoe Reservoir mixes with the 

volume in Kortes Reservoir. 

x Location 6 is at the outflow of Kortes Reservoir (Miracle Mile) and does not have inflows 

except for the outflow from Seminoe Reservoir. 

J-2 Seminoe Road Gas Development Project 
Draft Environmental Impact Statement November 2005

The locations of the modeled sites are shown in Figure 12, Produced Water Discharge Points 

– Alternative B. Additional details on the Mixing Model setup, assumptions, input parameters, 

and results are described in the Surface Water Modeling Technical Report (HydroGeo 2004c). 

Seminoe Road Gas Development Project J-3 
Appendix K 

Wildlife Monitoring and Protection Plan 
Table of Contents 


1.0 Introduction........................................................................................................................1


2.0 Implementation Protocol ..................................................................................................1


2.1 Annual Reports and Meetings .....................................................................................2


2.1.1 Reports ...................................................................................................................2


2.1.1 Meetings .....................................................................................................................3


2.2 Annual Inventory And Monitoring ...............................................................................3


2.2.1 Threatened, Endangered, Candidate, and Other Species of Concern ..................3


2.2.2 Raptors ...................................................................................................................6


2.2.3 Big Game Crucial Range........................................................................................6


2.2.4 Other Inventory and Monitoring Measures.............................................................7


2.2.5 General Wildlife ......................................................................................................7


2.3 Protection Measures.....................................................................................................7


2.3.1 TEC & SC ...............................................................................................................8


2.3.2 Raptors ...................................................................................................................9


2.3.3 Big Game Species................................................................................................11


2.3.4 General Wildlife ....................................................................................................11


3.0 Literature Cited ................................................................................................................12


List of Tables 

Table 1	 Summary of General Wildlife Reporting, Inventory, and Monitoring, Seminoe 

Road Natural Gas Development Project 

Table 2	 Summary of General APD/ROW Application Stage Survey/Protection 

Measures, Seminoe Road Natural Gas Development Project 

Table 3	 Threatened, Endangered, Candidate, and Sensitive Species Potential 

Occurring on or in the Vicinity of the Seminoe Road Natural Gas 

Development Project 

List of Figures 

Figure 1	 General Wildlife Observation Data Sheet 

Figure 2	 Mountain Plover Additional Protection Measures 

List of Maps 

Map 1	 Wildlife Survey Areas 

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1.0 Introduction 

This wildlife monitoring/protection plan was prepared in conjunction with the environmental impact 

statement (EIS) for the Seminoe Road Natural Gas Development Project (SRNGD). The goal of 

the plan is to avoid and/or minimize adverse impacts to wildlife present on project-affected areas 

by monitoring wildlife population trends on the SRNGD during the course of project development 

and operations and by developing appropriate mitigation actions. Map 1 shows the location of the 

SRNGD and associated wildlife monitoring areas. Implementation of the plan will allow land 

managers and project personnel opportunities to achieve and maintain desired levels of wildlife 

productivity and populations on the SRNGD (e.g., at pre-project levels) by minimizing and/or 

avoiding potential adverse impacts to wildlife species. In addition, the implementation of this plan 

will facilitate the maintenance of a diverse assemblage of wildlife populations on the SRNGD 

simultaneously with the development of natural gas reserves. 

The proposed SRNGD, located in Townships 21, 22, 23 and 24 North, Ranges 84, 85 and 86 

West, in Carbon County, Wyoming, involves the development of a maximum of 1,240 wells, on up 

to 785 well pad sites. Associated facilities would include access roads, gas and water pipelines, 

compressor stations; water disposal systems and an electric power supply system. The proposed 

life-of-project (LOP) is estimated to be 30 or more years. Alternative development strategies also 

have been proposed. A complete description of the proposed project and alternatives is provided 

in Chapter 2 of the EIS. 

Proposed inventory, monitoring, and protection measures will be implemented under each 

potential development scenario, except that the plan will not be implemented under the No Action 

Alternative. Implementation of the plan will begin in 2005, and is estimated to continue for the 

LOP; however, the plan may be terminated at the end of any year when there is sufficient 

evidence that wildlife populations and productivity in the SRNGD have been successfully 

protected. The plan will receive a major review for effectiveness every 5 to 6 years or as 

determined b y the Review Team. 

2.0 Implementation Protocol 

This section provides preliminary wildlife inventory, monitoring, and protection protocol. A 

summary of primary protocol components is provided in Table 1. Standard protocol for 

Application for Permit to Drill (APD) and right-of-way (ROW) application field reviews are provided 

in Table 2. Alternative protocols likely will be developed in the future in response to specific needs 

identified in annual reports (Section 2.1.1). Methods are provided for each wildlife 

species/category, and additional species/categories may be added based on needs identified in 

annual reports. The wildlife species/categories for which specific inventory, monitoring, and 

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protection procedures will be applied were developed based on management agency (Bureau of 

Land Management [BLM], U.S. Fish and Wildlife Service [USFWS], Wyoming Game and Fish 

Department [WGFD]) and individual concerns identified during the preparation of the EIS. 

Considerable efforts will be required by agency and operator personnel for plan implementation. 

Many of the annually proposed agency data collection activities are consistent with current 

agency requirements. Additionally, during annual planning (Section 2.1.2) and throughout project 

implementation, all efforts will be made to accommodate agency personnel schedules and 

responsibilities, and further agency cost-sharing approaches will be considered such that public 

demands and statutory directives are achieved. 

2.1 Annual Reports and Meetings 

2.1.1 Reports 

During project development, operators will provide an updated inventory and description of all 

existing project features (i.e., location, size, and associated level of human activity at each 

feature), as well as those tentatively proposed for development during the next 12 months in a 

format that is compatible with a Geographic Information System (GIS). This inventory will be 

submitted to the BLM by operators no later than October 15 of each calendar year. These data 

will be coupled with annual wildlife inventory, monitoring, and protection data obtained for the 

previous year and included in annual reports. Annual reports will be prepared by the operator or 

operators’ third party contractor with BLM oversight. Annual wildlife inventory, monitoring and 

protection data gathered in conjunction with the project will be provided to the BLM by October 15 

of each calendar year. 

Annual reports will summarize annual wildlife inventory and monitoring results, note any trends 

across years, identify and assess protection measures implanted during past year, specify 

monitoring and protection measures proposed for the upcoming year, recommend modifications 

to the existing wildlife monitoring/protection plan based on the success and/or failures of past 

years and identify additional species/categories to be monitored. Where possible, the data 

presented in reports will be used to identify potential correlations between development and 

wildlife productivity and/or abundance, as well as, sources of potential disturbance to wildlife. A 

GIS will be used for information storage; retrieval, planning, and annual GIS data updates will be 

conducted. Raw data collected each year also will be provided to other management agencies, at 

the request of the agencies. 

Annual reports will be completed in draft and submitted to the BLM, operators and other 

interested parties by November 15 of each year. A final annual report will be issued to all 

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potentially affected individuals and groups by early February of each year. Additional reports may 

be prepared in any year, as necessary, to comply with other relevant wildlife laws, rules, and 

regulations. 

2.1.1 Meetings 

A one day meeting will be organized by the BLM and held in December of each year to discuss 

and modify, as necessary, proposed wildlife inventory, monitoring and protection protocol for the 

subsequent year. A protocol regarding how to accommodate previously unidentified development 

sites will also be determined during the annual meeting. Any final decisions regarding wildlife 

inventory, monitoring and protection protocol will be made by the BLM based on the input of all 

affected parties. 

Additional meetings may be held in any given year to inform and update cooperators on the 

findings of additional reports as necessary. 

2.2 Annual Inventory And Monitoring 

Inventory and monitoring protocols will be as identified below for each wildlife species/category. 

These protocols will be unchanged across development alternatives, except as authorized by the 

BLM or specified in this plan. Additional wildlife species/categories and associated surveys may 

be added or wildlife species/categories and surveys may be omitted in future years, pending 

results presented in the coordinated review of annual reports. Opportunistic wildlife observations 

may be made throughout the year by agency and operator personnel present in the project area. 

The frequency of inventory and monitoring will be dependent upon the level of development in the 

project area. Inventory and monitoring results may lead to further, currently unidentifiable, 

scientific studies specifically designed to determine cause and effect. The review team and/or 

BLM will identify the level of effort required by this wildlife plan subject to the standard listed 

below. Site and species-specific surveys will be conducted in association with APD and ROW 

application field reviews. 

2.2.1 Threatened, Endangered, Candidate, and Other Species of Concern 

The level of inventory/monitoring required for threatened, endangered, candidate, and other 

species of concern (TEC & SC) will be commensurate with established protocols for the 

potentially affected species. All surveys will be conducted in coordination with the BLM. 

Methodologies and results of these surveys will be included in annual reports and provided in 

separate supplemental reports. A preliminary list of TEC & SC species proposed for management 

and known from or potentially occurring in the vicinity of the project area is shown on Table 3. As 

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TEC & SC species are added to or withdrawn from USFWS, BLM, and/or WGFD lists, 

appropriate modifications will be incorporated to this plan and specified in annual reports. 

TEC & SC data collected during surveys and described below will be provided only as necessary 

to those requiring the data for specific management and/or project development needs. Site- and 

species-specific TEC & SC surveys will be conducted as necessary in association with all APD 

and ROW application field reviews. 

2.2.1.1 Black-Footed Ferret 

The USFWS, in coordination with the WGFD, has developed a list of habitat blocks that are not 

likely to be inhabited by black-footed ferrets (block cleared). In these areas, take of individual 

ferrets and effects to a wild population are not an issue and surveys for ferrets are no longer 

recommended. Although ferret surveys are not required in these areas, the area may still 

maintain value for the survival and recovery of the species in the future. Additionally, areas 

remain that require ferret surveys (non-block cleared) in potential habitat. A portion of the project 

area coincides with the Seminoe complex, which is a non-block cleared area, requiring ferret 

surveys in areas that would likely result in the take of a ferret during project implementation. 

BLM biologists will determine the presence/absence of prairie dog colonies at each proposed 

development site during APD and ROW application field reviews. Prairie dog colonies in the 

project area will be mapped and burrow densities determined by a BLM-approved operatorfinanced biologist, as necessary and in association with proposed development plans. Colonies 

that meet USFWS criteria as potential black-footed ferret habitat (USFWS 1989), in non-block 

cleared areas, will be surveyed for black-footed ferrets by an USFWS-certified, operator-financed, 

surveyor prior to BLM authorizing disturbance of these colonies. Surveys will be conducted as 

deemed necessary, during consultation with the BLM and/or USFWS. Black-footed ferret surveys 

will be conducted in accordance with USFWS guidelines (USFWS 1989) and approved by BLM 

and USFWS. 

2.2.1.2 Bald Eagle, Peregrine Falcon, and Ferruginous Hawk 

Inventory and monitoring protocol for bald eagle, peregrine falcon, and ferruginous hawk will be 

as described for raptors (Section 2.2.2). 

2.2.1.3 Greater Sage-Grouse 

Sage grouse lek inventories will be conducted by the BLM on the project area and a two mile 

buffer to determine lek locations every 5 years, or as deemed appropriate by the BLM. Surveys 

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may be conducted aerially, with operator-provided financial assistance for aircraft rental, or on the 

ground, in order to determine lek locations. 

Selected leks within the two miles of existing and proposed disturbance areas will be monitored 

annually to determine lek attendance by the BLM or a BLM-approved operator-financed biologist, 

between March 1 and May 15, such that all leks on these areas are monitored at least once every 

3 years. Monitoring efforts will be implemented at all leks present on affected sections, two-mile 

buffers, and selected undeveloped comparison areas. The BLM will direct lek-monitoring efforts 

such that efforts are made to have the same individuals monitor the same leks within and across 

years. Data must be collected by all parties using accepted WGFD techniques and meeting 

accuracy standards agreed upon by WGFD and BLM. Standard site- and species-specific sage 

grouse lek surveys will be conducted as necessary in association with all APD and ROW 

application field reviews. 

2.2.1.4 Mountain Plover 

Mountain plover habitat will be mapped within proposed disturbance areas (as identified in annual 

reports) prior to development of these areas by the BLM or a BLM-approved operator-financed 

biologist. In addition, these areas will be surveyed annually by the BLM or a BLM-approved 

operator-financed biologist to detect the presence of plovers. Surveys will be conducted during 

the period of May 1 through June 20. Data collected during these surveys will be provided on 

mountain plover route survey forms. Standard site-specific habitat surveys will be conducted as 

necessary in association with all APD and ROW application filed reviews. 

2.2.1.5 Western Burrowing Owl 

Prairie dog colonies and other suitable burrowing owl nesting areas on and within 0.75 miles of 

existing and proposed disturbance areas will be searched for western burrowing owls by the BLM 

or during June through August to determine the presence or absence of nesting owls. If 

burrowing owls are found, attempts will be made to determine reproductive success. Standard 

site-specific surveys will be conducted in association with all APD and ROW application field 

reviews. 

2.2.1.6 Other TEC & SC Species 

Surveys for other TEC & SC species will be conducted by the BLM or a BLM-approved operatorfinanced biologist in areas of potential habitat within 0.5 mile of proposed disturbance sites prior 

to disturbance. These surveys may be implemented in conjunction with surveys for other species 

or as components of APD and/or ROW application processes. If any TEC & SC species are 

observed, the observations will be noted on appropriate data forms and efforts will be made to 

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determine their activities (e.g., breeding, nesting, foraging, hunting, etc.). If any management 

agency identifies a potential for concern regarding any of these species, additional inventory and 

monitoring and mitigation may be implemented as specified in annual reports. 

2.2.2 Raptors 

Raptor inventories will be conducted by the BLM, at least every five years or prior to development 

of proposed disturbance areas (as identified in annual reports), to determine the location of raptor 

nests. Raptor nest monitoring will be conducted by the BLM or a BLM approved operatorfinanced biologist, annually, at known nest locations, between April and July, in order to ascertain 

nest activity status. These surveys may be implemented aerially, via helicopter, or from the 

ground. Operators may provide financial assistance for aircraft rental. 

Nest productivity monitoring will be conducted by the BLM at active nests, for selected species, to 

determine nesting success. Monitoring generally will be conducted from the ground, and attempts 

will be made to determine the cause of any documented nest failure. Operators may provide 

financial assistance for aircraft rental, as necessary. Site- and species-specific raptor nest 

inventories will be conducted as necessary in association with all APD and ROW application field 

reviews. 

All raptor nest/productivity surveys will be conducted using procedures that minimize potential 

adverse effects to nesting raptors. Specific survey measures for reducing detrimental effects are 

listed in Grier and Fyfe (1987) and Call (1978) and include the following. 

x Nest visits will be delayed for as long as possible in the nesting season. 

x Nests will be approached cautiously, and their status (i.e., number of nestlings/fledglings) 

will be determined from distance with binoculars or a spotting scope. 

x Nests will be approached tangentially and in an obvious manner to avoid startling adults. 

x Nests will not be visited during adverse weather conditions (e.g., extreme cold, 

precipitation events, windy periods, and hottest part of the day). 

x Visits will be kept as brief as possible. 

x All inventories will be coordinated by the BLM. 

x The number of nest visits in any year will be kept to a minimum. 

x All raptor nest location data will be considered confidential. 

2.2.3 Big Game Crucial Range 

Data on big game use of crucial winter ranges on the project area and an adjacent one mile 

buffer will be requested annually by the BLM from the WGFD, as deemed necessary by the BLM. 

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This information will be used to assess the effectiveness of protection measures implemented for 

the project. 

2.2.4 Other Inventory and Monitoring Measures 

Additional inventory and monitoring measures may be applied for other species as specified in 

annual reports. Surveys will be conducted in adherence with protocol to be established by the 

BLM, other agencies and operators. Operators may provide financial assistance for these 

investigations. 

2.2.5 General Wildlife 

BLM staff will be responsible for maintaining records of selected wildlife species observed during 

the course of their activities on the project area. Operator personnel may also provide data on 

wildlife observations. The information provided will include observations of wildlife species, their 

numbers, location, activity, and other pertinent data as applicable and identified on the General 

Wildlife Observation Data Sheet presented in Figure 1 of this plan. Where operators are uncertain 

of the USGS coordinates for an observation, a general description of the location may be 

provided and in instances where species of sex information is questionable, operators will identify 

the observation as such. 

2.3 Protection Measures 

The wildlife protection measures proposed herein have been developed from past measures 

identified for oil and gas developments in Wyoming. Additional measures may be included and/or 

existing measures may be modified in any given year as allowable and as deemed appropriate by 

BLM in consultation with other agencies, operators and interested parties. These measures will 

be specified in annual reports. Protection measures will be implemented by operators with 

assistance from and/or in consultation with the BLM. In addition, these measures may be 

modified on a site-specific basis as deemed appropriate by the BLM after completion of APD and 

ROW application field reviews. 

The principal protection measure for most wildlife will be species- and project-specific measures 

as well as general wildlife protection measures (Section 2.3.4). Implementation of these 

measures may benefit other wildlife species found on and adjacent to the project area. 

Sensitive/crucial habitats should be avoided where possible. 

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2.3.1 TEC & SC 

USFWS and WGFD consultation and coordination will be conducted for all protection activities 

relating to TEC & SC species and their habitats. Where possible, these actions will be specified in 

advance in the annual reports. 

2.3.1.1 Black-footed Ferret 

In general, all prairie dog colonies on the project area will be avoided, where practical. If prairie 

dog colonies, in non-block cleared areas, of sufficient size and burrow density for black-footed 

ferrets are scheduled to be disturbed, black-footed ferret surveys of these colonies will be 

conducted pursuant to BLM and/or USFWS decisions made during informal consultations. Survey 

protocol will adhere to USFWS guidelines as established in USFWS (1989) and will be conducted 

by a USFWS-qualified biologist a maximum of one year in advance of the proposed disturbance. 

Reports identifying survey methods and results will be prepared and submitted to the USFWS 

and BLM in accordance with Section 7 of the Endangered Species Act of 1973, as amended, and 

the Interagency Cooperation Regulations. Surveys will be financed by the operators. 

If black-footed ferrets are found on the project area, the USFWS will be notified immediately and 

formal consultations will be initiated to develop strategies that ensure no adverse effects to the 

species. Before ground-disturbing activities are initiated in black-footed ferret habitat, 

authorizations to proceed must be received from the BLM, in consultation with the USFWS. 

2.3.1.2 Bald Eagle, Peregrine Falcon, and Ferruginous Hawk 

Protection protocol will be as described for raptors (see Section 2.3.2). Additional measures will 

be applied on a species- or site-specific bases, as deemed appropriate by the BLM and/or 

USFWS, and specified in annual reports. 

2.3.1.3 Greater Sage-Grouse 

Surface disturbance or occupancy will be prohibited with 0.25 miles of the perimeter of occupied 

greater sage-grouse leks; Human activity would be avoided between 6:00 p.m. and 9:00 a.m. 

from March 1 to May 20 within 0.25 miles of the perimeter of occupied greater sage-grouse leks; 

Surface disturbance and other actions that create permanent and high-profile structures such as 

buildings, storage tanks and overhead power lines, will not be constructed within 0.25 to 1.0 mile 

of the perimeter of greater sage-grouse leks on and adjacent to the project area, as determined 

on a case-by-case basis; Surface disturbing and disruptive activities will not be allowed within two 

miles of an occupied greater sage-grouse lek or in nesting and early brood-rearing habitat 

associated with individual leks (when identified and delineated), from March 1 to July 15; Surface 

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disturbing and disruptive activities will not be allowed between November 15 and March 14 in 

delineated winter concentration areas; and, in order to minimize noise disturbances to strutting 

greater sage-grouse, compressor stations will be muffled with hospital style mufflers. Other 

techniques and/or equipment can be utilized, when it is demonstrated that they result in similar or 

increased noise reduction. Additional noise reduction techniques may be required if research 

shows that current techniques are not adequate. 

2.3.1.4 Mountain Plover 

Mountain plover habitat will be avoided where practical. Where these habitats will be disturbed, 

reclamation will utilize procedures designed to reestablish suitable plover habitat. The primary 

protection measure for mountain plover on the project area will be avoidance plover habitat 

during the breeding season. All surface-disturbing activities will be restricted from April 10 to July 

10 in mountain plover habitat. Addition protection measures, as shown in figure 2, may be 

implemented in identified mountain plover occupied habitat (i.e., areas where broods and/or 

adults have been observed in the current year or documented in at least 2 of the past 3 years). 

2.3.1.5 Western Burrowing Owl 

Protection protocol will be as described for raptors (Section 2.3.2) as well as avoidance of prairie 

dog colonies, where practical (Section 2.3.1.1). 

2.3.1.6 Other TEC&SC Species 

If crucial features for any TEC & SC species are found during surveys of areas within 0.5 miles of 

proposed disturbance sites, avoidance of these features will be accomplished in consultation and 

coordination with BLM, USFWS, and WGFD. Construction activities in these areas will be 

curtailed until there is concurrence between BLM, USFWS, and WGFD on what activities can be 

authorized. Activities will, in most cases, be delayed until such time that no adverse effects will 

occur. 

It is assumed that protocol specified in Section 2.3.4 for general wildlife will likely benefit TEC & 

SC species as well. If any management agency identifies a potential for impacts to any TEC & 

SC species, additional measures may be implemented as specified in annual reports. 

2.3.2 Raptors 

The primary protection measure for raptor species on the project area will be avoidance of nest 

locations during the breeding season. All surface-disturbing activities will be restricted from 

February 1 through July 31 within a 0.75 to 1.0 mile radius of raptor nests, depending upon 

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species. In addition, well locations, roads, ancillary facilities, and other surface structures 

requiring a repeated human presence will not be constructed within 825 feet of raptor nests, 

except ferruginous hawk, where the restriction will be to 1,200 feet (restrictions will generally 

exclude surface disturbance). 

Operators will notify the BLM immediately if raptors are found nesting on or within 1,200 feet of 

project facilities, and operators will assist the BLM as necessary in erecting artificial nesting 

structures (ANSs), as appropriate. The use of ANSs will be considered as a last resort for raptor 

protection. If nest manipulation or a situation requiring a “taking” of a raptor nest becomes 

necessary, a special permit will be obtained from the Denver USFWS Office, Permit Section, and 

will be initiated with sufficient lead time to allow for development of mitigation. Required 

corresponding permits will be obtained from the WGFD in Cheyenne. Consultation and 

coordination with the USFWS and WGFD will be conducted for all protection activities relating to 

raptors. 

If it is found that project activities could potentially affect raptor nesting on or adjacent to the 

project area, as determined from decreased raptor productivity or nesting, or documented nest 

abandonment or failure, ANSs may be constructed at a rate of up to two ANSs for on impacted 

nest. Existing degraded raptor nests may be upgraded or reinforced to minimize potential 

impacts. ANSs will be located within the nesting territory of potentially affected raptor pairs, 

outside of the line-of-sight or nest buffer of actively nesting pairs, where possible. Operators will 

be responsible for the annual maintenance of ANSs throughout the LOP. Annual ANS 

maintenance activities will be completed after August 15 and prior to October 15 each year, as 

necessary. All ANSs on public lands will become the property of the BLM upon completion of the 

project. Pertinent data regarding ANSs or nests proposed for upgrading will be identified in 

annual reports. 

In cases where existing project features are located within the nest buffers of active raptor nests, 

no prolonged maintenance activities will be allowed during critical periods. The exact dates of 

exclusion will be determined by the BLM and will likely vary between nests and from year to year, 

depending on the species present and variations in weather, nesting chronology, and other 

factors. 

Any power line construction will follow the recommendations of the Avian Power Line Interaction 

Committee (APLIC) (1994, 1996) and Olendorff et al. (1981) to avoid collisions and/or 

electrocution of raptors. 

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2.3.3 Big Game Species 

No construction activities or prolonged maintenance actions will be conducted within big game 

crucial winter range during the crucial winter periods of November 15 – April 30. If right-of-way 

fencing is required, it will be kept to a minimum, and the fences will meet BLM/WGFD approval 

for facilitating wildlife movement. Wildlife-proof fencing will be used only to enclose areas that are 

potentially hazardous to wildlife species, or reclaimed areas where it is determined that wildlife 

species are impeding successful vegetation establishment. Snow fences, if used, will be limited to 

segments of 0.25 miles or less. Project personnel will also be advised to minimize stopping and 

exiting their vehicles in big game winter habitat during crucial winter periods. In addition, escape 

openings will be provided along roads in big game crucial winter ranges, as designated by the 

BLM, to facilitate exit of big game animals from snowplowed roads. Additional habitat 

protection/improvement measures may also be applied in any given year as directed by the BLM, 

in consultation with operators and other agencies, and specified in annual reports. 

2.3.4 General Wildlife 

Unless otherwise indicated, the following protection measures will be applied for all wildlife 

species. Additional measures primarily designed to minimize impacts to other project area 

resources (e.g., vegetation and surface water resources, including wetlands, steep slopes, etc.) 

are identified in EIS section 2.8 and Chapter 4, and these measures may provide additional 

protection for wildlife. Additional actions may be applied in any given year to further minimize 

potential impacts to wildlife. These actions will be specified in annual reports. 

All roads on and adjacent to the project area that are required for the proposed project will be 

appropriately constructed, improved, maintained, and signed to minimize potential wildlife/vehicle 

collisions and facilitate wildlife (most notably big game) movement through the project area. 

Appropriate speed limits will be adhered to on all project roads, and operators will advise 

employees and contractors regarding these speed limits. Some existing roads on the project area 

and surrounding transportation planning area may be reclaimed if they become redundant or 

closed (gated and locked) to deny unnecessary access. 

To protect important habitat in portions of the project area (i.e., ephemeral draws dominated by 

basin big sagebrush) areas with sagebrush greater than three feet tall will be avoided where 

possible. 

Addition non-species-specific wildlife mitigations include the following. 

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Reserve, workover, and flare pits and other locations potentially hazardous to wildlife will be 

adequately protected by netting and/or fencing as directed by the BLM to prohibit wildlife access. 

If dead or injured raptors, big game, migratory birds, or unusual wildlife are observed on the 

project area, operator personnel will contact the appropriate BLM and WGFD offices. Under no 

circumstances will dead or injured wildlife be approached or handled by operator personnel. 

Employee and contractor education will be conducted regarding wildlife laws. If violations are 

discovered on the project area, operators will immediately notify the appropriate agency. If the 

violation is committed by an employee or contractor, said employee or contractor will be 

disciplined and may be dismissed by the operator and/or prosecuted by the WGFD and/or 

USFWS. 

Operators will implement policies designed to control off-site activities of operational personnel 

and littering, and will notify all employees (contract and company) that conviction of a violation 

can result in disciplinary action, including dismissal. 

Additional project- and site-specific mitigation measures may be added in future years, as 

specified in annual reports. 

3.0 Literature Cited 

Avian Power Line Interaction Committee. 1994. Mitigating bird collisions with power lines: The 

state of the art in 1994. Edison Electric Institute, Washington, D.C. 78 pp. + append. 

Baxter, G.T., and M.D. Stone. 1980. Amphibians and reptiles of Wyoming. Wyoming Game and 

Fish Department, Bulletin No. 16. 137 pp. 

Call, M.W. 1978. Nesting habitats and surveying techniques for common western raptors. U.S. 

Department of the Interior, Bureau of Land Management, Technical Note No. 316. 115 

pp. 

Cerovski, A.O., M. Grenier, B. Oakleaf, L. Van Fleet, and S. Patla. 2004. Atlas of Birds, 

Mammals, Amphibians, and Reptiles in Wyoming. Wyoming Game and Fish Department 

Nongame Program, Lander. 206pp. 

Dorn, J.L., and R.D. Dorn. 1990. Wyoming birds. Mountain West Publishing, Cheyenne, 

Wyoming. 138 pp. 

Grier, J.W., and R.W. Fyfe. 1987. Preventing research and management disturbance. Pages 173­

182 In B.A.G. Pendleton, B.A. Milsap, K.W. Cline, and D.M. Bird, editors. Raptor 

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management techniques. Institute of Wildlife Research, National Wildlife Federation, 

Scientific and Technical Series No. 10. 420 pp. 

Olendorff, R.R., A.D. Miller, and R.M. Lehman. 1981. Suggested practices for raptor protection on 

power lines: The state of the art in 1981. 

Raptor Research Report No. 4, Raptor Research Foundation, Inc., University of Minnesota, St. 

Paul 111 pp. 

Stebbins, R.C. 2003. Western Reptiles and Amphibians, 3rd Ed. Houghton Mifflin Company, 

Boston, Massachusetts and New York, New York. 533pp. 

U.S. Fish and Wildlife Service. 1989. Black-footed ferret survey guidelines for compliance with the 

Endangered Species Act. U.S. Fish and Wildlife Service, Denver, Colorado and 

Albuquerque, New Mexico (April 1989). 10 pp + append. 

K-13

Table 1 – Summary of General Wildlife Reporting, Inventory, and Monitoring, Seminoe 

Road Natural Gas Development Project 

Action Dates Responsible Entity 

Annual tentative plan of 

development 

By October 15, annually Operator 

Annual inventory, monitoring 

and protection data 

By October 15, annually 

Annual reports Annually: 

Draft – early November 

Final – early January 

Operator 

Annual meeting December and as necessary BLM with participation by other 

agencies and operators 

Inventory/Monitoring 

Raptor nest inventory At least every five years, prior to 

development 

BLM or BLM approved operator 

financed biologist with operator 

provided financial assistance for 

aircraft rental, as necessary 

Raptor monitoring Annually from April to July BLM or BLM approved operator 

financed biologist with operator 

provided financial assistance for 

aircraft rental, as necessary 

Greater sage-grouse lek 

inventory 

At least every five years BLM or BLM approved operator 

financed biologist with operator 

provided financial assistance for 

aircraft rental, as necessary 

Greater sage-grouse lek 

monitoring 

Annually from March to mid-May BLM or BLM approved operator 

financed biologist 

Big game crucial winter range 

use/monitoring 

As available BLM will request data from WGFD 

Mountain Plover surveys Annually from May to June BLM or BLM approved operator 

financed biologist 

K-14

Table 2, Summary of General APD/ROW Application Stage Survey/Protection Measures, 

Seminoe Road Natural Gas Development Project 

Protection Measure Dates Responsible Entity 

Raptor nest survey/inventory 

within 0.75 to 1.0 miles of 

proposed disturbance 

Yearlong BLM, operator 

Raptor nest season avoidance 

within 0.75 to 1.0 miles 

February 1 to July 31 BLM, operator 

Raptor nest avoidance with 825 

feet (1200 feet for ferruginous 

hawk nests) 

Yearlong BLM, operator 

BLM Yearlong, as necessary BLM, operator 

BLM Yearlong, as necessary BLM, operator 

BLM Yearlong, as necessary BLM, operator 

BLM Yearlong, where practical BLM, operator 

Black-footed ferret surveys As appropriate in accordance with 

USFWS guidelines 

Operator financed USFWSapproved biologist 

Mountain Plover habitat surveys Yearlong BLM, operator 

Mountain Plover nest/brood 

avoidance 

April 10 to July 10 BLM, operator 

Greater sage-grouse lek/nesting 

habitat avoidance within 2.0 

miles of proposed disturbance 

March 1 to June 30 BLM, operator 

Greater sage-grouse lek 

avoidance within 0.25 miles of 

proposed disturbance 

Yearlong BLM, operator 

Big game crucial winter range 

avoidance 

November 15 to April 30 BLM, operator 

General wildlife 

avoidance/protection 

A necessary BLM, other agencies, operator 

K-15

Table 3, Threatened, Endangered, Candidate, and Sensitive Species Potentially Occurring 

on or in the Vicinity of the Seminoe Road Natural Gas Development Project 

Species Habitat 

Endangered Species 

Black-footed Ferret Prairie dog colonies with black-tailed prairie dog complex greater 

than 80 acres or white-tailed prairie dog complex greater than 200 

acres 

Threatened Species 

Bald Eagle Conifers, cottonwood-riparian river ecosystems 

Endangered/Threatened Species 

North Platte River species Platte River System 

Candidate Species 

Western boreal toad Riparian habitat above 7,500 feet in elevation 

BLM Wyoming Sensitive Species 

Swift Fox Grasslands 

Townsend’s Big-eared Bat Forests, basin-prairie shrub, caves and mines 

White-tailed Prairie Dog Basin-prairie shrub, grasslands 

Wyoming Pocket Gopher Meadows with loose soil 

Baird’s Sparrow Grasslands, weedy fields 

Brewer’s Sparrow Basin-prairie shrub 

Burrowing Owl Grasslands, basin-prairie shrub 

Ferruginous Hawk Basin-prairie shrub, grassland, rock outcrops 

Greater Sage-grouse Basin-prairie shrub, mountain-foothill shrub 

Loggerhead Shrike Basin-prairie shrub, mountain foothill shrub 

Long-billed Curlew Grasslands, plains, foothills, wet meadows 

Peregrine Falcon Tall Cliffs 

Sage Thrasher Basin-prairie shrub, mountain foothill shrub 

Trumpeter Swan Lakes, ponds, rivers 

White-faced Ibis Marshes, wet meadows 

Northern Leopard Frog Beaver ponds, permanent water in plains and foothills 

K-16

Figure 1, General Wildlife Observation Data Sheet


Species Date Time Datum 

(i.e. NAD 

27/83) 

UTM 

Zone 

Northing Easting # 

Adult 

# 

Juvenile 

Distance 

(meters) 

Direction 

(degrees) 

K-17

Figure 2, Mountain Plover Additional Protection Measures


Mountain Plover- Additional Protection Measures 

x To protect the identified mountain plover occupied habitat, the proposed activity will not be allowed 

as proposed. An alternative such as moving the facility, directional drilling, piping and storage of 

condensate off the identified mountain plover occupied habitat to a centralized facility, or other 

technique for the minimization of ground disturbance and habitat degradation will be required. 

x To protect the identified mountain plover occupied habitat, the proposed facility will be moved 1⁄2 

mile from the identified occupied habitat. 

x To protect the identified mountain plover occupied habitat and because mountain plover adults and 

broods may forage along roads during the night, traffic speed and traffic volume will be limited 

during nighttime hours from April 10 to July 10. 

x Within 1⁄2 mile of the identified mountain plover occupied habitat, speed limits will be posed at 25 

mph on resources roads and 35 mph on local roads during the brood rearing period (June 1-July 

10). 

x The access road will be realigned to avoid the identified mountain plover occupied habitat. 

x To protect the identified mountain plover occupied habitat, traffic will be minimized from Jun 1-July 

10 by car-pooling and organizing work activities to minimize trips on roads within 1⁄2 mile of the 

mountain plover occupied habitat. 

x To protect the identified mountain plover occupied habitat, work schedules and shift changes will 

be modified from Jun 1-July 10 to avoid the periods of activity from 1⁄2 hour before sunrise to 1⁄2 hour 

after sunset. 

x To protect the identified mountain plover occupied habitat, power lines will be either buried or poles 

will include a perch inhibitor in their design. This will be required within 1⁄2 mile of the identified 

mountain plover occupied habitat. 

x To protect the identified mountain plover occupied habitat, fences, storage tanks, and other 

elevated structures will be either constructed as low a possible and/or will incorporate perchinhibitors into their design. 

x Road-killed animals will be promptly removed from areas within 1⁄2 miles the identified mountain 

plover occupied habitat. 

x To protect the identified mountain plover occupied habitat, seed mixes and application rates for 

reclamation will be designed to produce stands of sparse, low-growing vegetation suitable for 

plover nesting. 

x To minimize destruction of nests and disturbance to breeding mountain plovers, no reclamation 

activities or other ground-disturbing activities will occur from April 10 to July 10 unless surveys 

consistent with the Plover Guidelines or other USFWS approved method find that no plovers are 

nesting in the area. 

x A plugged and abandoned well within 1⁄2 mile of the identified mountain plover occupied habitat will 

be identified with a marker 4 feet tall with a perch inhibitor on the top of the marker. 

K-18


Appendix L 

Biological Assessment 
Draft


Biological Assessment


of


Threatened, Endangered, Proposed, and Candidate Species


for the


Seminoe Road Gas Development Project


Prepared by 

U.S. Department of the Interior


Bureau of Land Management


Rawlins Field Office


Rawlins, Wyoming


and


Cedar Creek Associates, Inc.


Fort Collins, Colorado


February 2005

TABLE OF CONTENTS 

Page No. 

1.0 Project Description........................................................................................................ L-1


1.1 Alternative A (No Action)......................................................................................... L-2


1.2 Alternative B (Proposed Action).............................................................................. L-2


1.3 Alternative C (Pipeline to Reservoir)....................................................................... L-3


1.4 Alternative D (Underground Injection)..................................................................... L-4


2.0 Methods ........................................................................................................................ L-4


2.1 Published Literature................................................................................................ L-4


2.2 Unpublished Agency Reports and Data.................................................................. L-4


2.3 Personal Communications ...................................................................................... L-5


2.4 Meetings ................................................................................................................. L-5


2.5 Field Surveys .......................................................................................................... L-6


2.6 BA Preparation........................................................................................................ L-6


3.0 Species Current Status and Habitat Use ...................................................................... L-6


3.1 Threatened, Endangered, Proposed, and Candidate Species ............................... L-7


3.1.1 Black-footed Ferret (Endangered) ................................................................. L-7


3.1.2 Canada Lynx (Threatened)............................................................................ L-8


3.1.3 Preble’s Meadow Jumping Mouse (Threatened) ........................................... L-8


3.1.4 Bald Eagle (Threatened................................................................................. L-9


3.1.5 Yellow-billed Cuckoo (Candidate).................................................................. L-9


3.1.6 Western Boreal Toad (Candidate) ............................................................... L-11


3.1.7 Wyoming Toad (Endangered)...................................................................... L-12


3.1.8 Blowout Penstemon (Endangered).............................................................. L-12


3.1.9 Ute Ladies’-tresses Orchid (Threatened)..................................................... L-13


3.1.10 Colorado Butterfly Plant (Threatened) ....................................................... L-14


3.2 Platte River Species.............................................................................................. L-14


3.2.1 Whooping Crane (Endangered)................................................................... L-14


3.2.2 Interior Least Tern (Endangered)................................................................. L-14


3.2.3 Piping Plover (Threatened).......................................................................... L-15


3.2.4 Eskimo Curlew (Endangered)...................................................................... L-15


3.2.5 Bald Eagle (Threatened).............................................................................. L-15


3.2.6 Pallid Sturgeon (Endangered)...................................................................... L-16


3.2.7 Western Prairie Fringed Orchid (Threatened).............................................. L-16


3.3 Petitioned Species ................................................................................................ L-16


3.3.1 Pygmy Rabbit............................................................................................... L-17


3.3.2 Columbian Sharp-tailed Grouse................................................................... L-17


4.0 Direct and Indirect Impacts of the Proposed Project................................................... L-18


4.1 Proposed Action.................................................................................................... L-18


4.1.1 Threatened, Endangered, Proposed, and Candidate Species .................... L-18


4.1.2 Platte River Species..................................................................................... L-22


L-i

4.2 Alternative A – No Action ...................................................................................... L-23


4.3 Alternative C (Pipeline to Reservoir)..................................................................... L-23


4.4 Alternative D (Underground Injection)................................................................... L-23


5.0 Cumulative Impacts..................................................................................................... L-24


6.0 Coordination Measures to Avoid or Reduce Adverse Impacts.................................... L-25


6.1 Standard BLM Stipulations ................................................................................... L-27


7.0 Effects of the Project on the Expected Status of Species in the Future...................... L-28


8.0 References Cited ........................................................................................................ L-28


L-ii
1.0 PROJECT DESCRIPTION 

This Biological Assessment (BA) discusses the potential effects of the proposed 

Seminoe Road Gas Development (Seminoe Road) Project on threatened and 

endangered species, proposed species, and candidate and petitioned species pursuant 

to the Endangered Species Act (ESA) of 1973. This BA also presents recommendations 

to assure that the construction and subsequent operation of the proposed project will 

neither jeopardize the continued existence of those species nor result in the destruction 

or adverse modification of their critical habitats. Analysis of effects of this proposed 

project on threatened, endangered, proposed, and candidate species complies with the 

provisions of the ESA. 

Dudley & Associates, LLC (Dudley) has notified the Bureau of Land Management (BLM), 

Rawlins Field Office, that Dudley intends to drill additional development wells within the 

Seminoe Road Project Area (SRPA). The SRPA currently contains 16 active producing 

wells, with accompanying production-related facilities within the smaller Seminoe Road 

Pilot Area. Two additional wells have been approved, but those locations have not yet 

been developed. The pilot project wells are drilled and spaced on 160-acre units. The 

pilot project wells and associated roads lie in Townships 23 and 24 North, Range 85 

West, 6th PM, Carbon County, Wyoming. 

While the Seminoe Road Environmental Impact Statement (EIS) is being prepared, BLM 

may approve additional interim coalbed methane gas wells within an expanded Pilot 

Area in the SRPA. The objective of the Pilot Area wells is to allow Dudley to drill, 

complete, and produce sufficient wells to determine which geologic objectives are gas 

productive, which drilling and completion techniques are economical, if dewatering of the 

drilling objectives can be achieved, and what depths or pressure windows may be 

preferred to target economic gas production. 

The SRPA is located in Townships 21, 22, 23 and 24 North, Ranges 84, 85 and 86 

West, 6th Principal Meridian (PM) in the northwest Hanna Basin, Carbon County, 

Wyoming. The project area is located approximately 20 miles northeast of the City of 

Rawlins, 18 miles north-northeast of the Town of Sinclair, and generally east of Carbon 

L-1
County Road 351 (Seminoe Road), although portions of the SRPA also lie to the west of 

Seminoe Road (see Figure 1, General Location Map). 

The project area is approximately 137,000 acres (215 sections) in size and 

encompasses a checkerboard ownership pattern of federal (>49 percent) and private 

(fee) (>49 percent), with some state surface. The BLM Rawlins Field Office manages 

the federal surface and mineral estates. Dudley owns or controls oil and gas leasehold 

interests comprising approximately 80 percent of the project area. The BLM manages 

the balance of the leased and un-leased federal oil and gas interests in the project area. 

Four alternatives are being analyzed in the EIS being prepared for the proposed project: 

No Action (Alternative A), Proposed Action (Alternative B), Direct Discharge (Alternative 

C), and Underground Injection (Alternative D). Descriptions of each alternative are 

discussed in detail in Chapter 2 of the Draft EIS (BLM 2005) and are summarized below. 

1.1 Alternative A (No Action) 

Under the No Action Alternative, there would be no additional gas development or 

production activities beyond those permitted under the existing Pilot Project, and there 

would be no additional effects to wildlife habitat or wildlife species. As a result, wildlife 

habitat distribution, extent, and condition as well as wildlife populations would remain 

similar to existing conditions, assuming there are no major alterations in current land use 

activities or practices. Wildlife habitats within the SRPA would continue to be subject to 

low levels of disturbance in the form of existing gas production wells as well as livestock 

grazing, recreation, and coal mining. 

1.2 Alternative B (Proposed Action) 

Full project development would result in an initial direct habitat loss of 6,174 acres or 4.5 

percent of the SRPA over an approximate 9-year period. Specific well locations are not 

known at this time, but gas well development would occur at a scale of four wells per 

section or per square mile (160-acre spacing). In addition, some surface locations within 

the SRPA may not be feasible to drill, either for economical (e.g., high road construction 

costs), physical (e.g., steep terrain), or other environmental reasons (e.g., proximity to 

the North Platte River or Seminoe Reservoir). 

L-2
Much of the initial disturbance associated with well pads, roads, and utility installation 

would be reclaimed following well development and infrastructure construction. The 

area that would remain disturbed for operations during the approximate 30-year life of 

project would be approximately 2349 acres or 1.7 percent of the SRPA. A total of 3,825 

acres would be reclaimed to grassland habitat as soon as possible after well installation 

and associated construction are completed. Specifics on reclamation timing, goals, and 

methodology are provided in the reclamation plan contained within the Seminoe Road 

Project Draft EIS (BLM 2005). The remaining acreage would not be reclaimed until the 

cessation of project operations. 

Discharge of produced water would result in the development of narrow, linear wetland 

habitats along the discharge drainages, and watering areas for wildlife would be 

available in the proposed discharge drainages. In addition, year-round inundation of the 

three closed playa basins (St. Mary’s Anticline Basin, Alkali Flats, and Ferris Lake) from 

produced water discharge south of Seminoe Reservoir and the North Platte River would 

create additional wildlife watering areas and wetland habitat in these basins for the life of 

the project. 

1.3 Alternative C (Direct Discharge) 

This alternative would be similar to the Proposed Action except that produced water 

would be piped directly to the North Platte River and Seminoe Reservoir rather than 

being released down existing ephemeral drainages. As a result, there would be no 

development of narrow, linear wetland habitats along the discharge drainages, but some 

discharge water would be made available at strategic locations for wildlife and livestock 

use. In addition, year-round inundation of the three closed playa basins: St. Mary’s 

Anticline Basin, Alkali Flats, and Ferris Lake would not occur, thereby reducing the 

amount of wildlife watering areas and potential wetland habitat development in these 

basins for the life of the project. Water quality and quantity effects in the North Platte 

River and Seminoe Reservoir would be the same as described for the Proposed Action 

except the quantity of produced water reaching these receiving waters would be about 

5,000 acre-feet or 7 percent greater than the Proposed Action, because there would be 

no infiltration into alluvium/colluvium or evaporation along the drainages. 

L-3
1.4 Alternative D (Underground Injection) 

This alternative would be similar to the Proposed Action except that produced water 

would not be discharged into the North Platte River, Seminoe Reservoir, or the closed 

basin playas. Similar to Alternative C, there would be no potential for development of 

wetland habitats within discharge drainages or in the closed basin playas, but some 

discharge water would be made available at strategic locations for wildlife and livestock 

use. There would also be no produced water available for wildlife use in the closed 

basin playas. 

2.0 METHODS 

The assessments and recommendations contained within this BA are based upon 

information obtained from several sources: (1) published literature, (2) unpublished 

agency reports and data, (3) personal communications with state and federal agency 

wildlife specialists, (4) meetings with state and federal agency plant and wildlife 

specialists, and (5) field surveys. 

2.1 Published Literature 

Published scientific documents that pertain directly to the specific circumstances and 

issues involved in this analysis were reviewed and incorporated into this BA. Literature 

sources used in this assessment are appropriately cited. 

2.2 Unpublished Agency Reports and Data 

Unpublished documents and data from the files of the Wyoming Game and Fish 

Department (WGFD) and U.S. Fish and Wildlife Service (USFWS) were reviewed, 

utilized, and referenced, where applicable, in this BA. Available data on threatened and 

endangered species in the project area were reviewed in the preparation of the Draft EIS 

and this BA. Materials reviewed include distribution and habitat maps, progress reports, 

recovery plans, sighting records, management plans, and survey guidelines for 

threatened and endangered species. 

L-4
Some information concerning historical wildlife usage of the project area was obtained 

through the BLM Rawlins Field Office and District IV biologists of the WGFD. This 

information was specific to current and historical locations for wildlife species. The 

Wyoming Natural Diversity Database (WYNDD) was also queried for reports of rare or 

unique plant and wildlife species within the SRPA. 

2.3 Personal Communications 

Individuals interviewed during the fact-finding process, either directly or by telephone, 

included: Mr. Larry Apple and Heath Cline (BLM Wildlife Biologists, Rawlins), Ms. 

Kathleen Erwin (USFWS Biologist, Cheyenne), and Mr. Greg Hiatt (WGFD Wildlife 

Biologist, Sinclair). 

2.4 Meetings 

Numerous meetings were held among state and federal wildlife specialists and Cedar 

Creek Associates, Inc. (Cedar Creek) concerning potential impacts to wildlife that may 

result from the proposed project. Concerns raised in these meetings regarding 

development of the proposed project have been addressed in either this BA or in the 

Draft EIS (BLM 2005). 

2.5 Field Surveys 

Existing special status wildlife information available from the BLM and WGFD for the 

project area was supplemented through wildlife surveys conducted by Cedar Creek and 

TRC from 2000 to 2004. These data collections consisted of aerial and ground surveys 

to determine: (1) occurrence of threatened, endangered, proposed, candidate, or 

sensitive species and/or habitats in the SRPA; (2) the occurrence, location, size, and 

burrow density of white-tailed prairie dog colonies within portions of the SRPA; (3) 

presence or absence of black-footed ferrets within portions of the SRPA, and (4) the 

location and activity status of raptor nests within portions of the SRPA. 

L-5
2.6 BA Preparation 

Personnel who cooperated in the preparation of this BA were Michael Phelan, wildlife 

biologist with Cedar Creek Associates, Inc. (Cedar Creek) and Heath Cline, wildlife 

biologist with the BLM. Cedar Creek and TRC staff biologists assisted in the collection 

of field data. 

3.0 SPECIES CURRENT STATUS AND HABITAT USE 

The USFWS has determined that 14 species, listed under the ESA as threatened, 

endangered, proposed, or candidate or as a petitioned species pursuant to the ESA, are 

potentially present within the area under the management of the Rawlins BLM Field 

Office (USFWS 2004a; Table 1). In addition, four federal endangered and two 

threatened species have been identified as susceptible to downstream water depletions 

in the North Platte River system. 

Common Name Scientific Name Status 

Mammals 

Black-footed ferret Mustela nigripes Endangered 

Canada lynx Lynx Canadensis Threatened 

Preble’s meadow jumping mouse Zapus hudsonius preblei Threatened 

Pygmy rabbit Brachylagus idahoensis Petitioned 

Birds 

Bald eagle* Haliaeetus leucocephalus Threatened 

Yellow-billed cuckoo Coccyzus americanus Candidate 

Columbian sharp-tailed grouse Tympanuchus phasianellus columbianus Petitioned 

Whooping crane* Grus Americana Endangered 

Interior least tern* Sterna antillarum Endangered 

Piping plover* Charadrius melodus Threatened 

Eskimo curlew* Numenius borealis Endangered 

Amphibians 

Western boreal toad Bufo boreas boreas Candidate 

Wyoming toad Bufo baxteri Endangered 

Fish 

Pallid sturgeon* Scaphirhynchus albus Endangered 

Plants 

Blowout penstemon Penstemon haydenii Endangered 

Ute-ladies’-tresses Spiranthes diluvialis Threatened 

Colorado butterfly plant Gaura neomexicana ssp. Coloradensis Threatened 

Western prairie fringed orchid* Platanthera praeclara Threatened 

* Water depletions in the Platte River system may affect these species found downstream of the SRPA, but 

there would be no water depletions resulting from the Seminoe Road Project. 

L-6 
There would be no downstream water depletions associated with any of the alternatives, 

and water would be added to the North Platte River system under Alternatives B and C. 

All of these species and their federal status under the ESA are listed in Table 1. 

3.1 Threatened, Endangered, Proposed, and Candidate Species 

3.1.1 Black-footed Ferret (Endangered) 

The black-footed ferret’s original distribution in North America closely corresponded to 

that of prairie dogs (Hall and Kelson 1959, Fagerstone 1987). Black-footed ferrets were 

considered extinct until a small population was discovered near Meeteetsee, Wyoming in 

1981. Much of our current knowledge of this species is based on studies completed on 

the Meeteetsee population. Following an outbreak of distemper, surviving ferrets were 

brought into captivity and a captive breeding program was initiated. Since then a nonessential experimental population of black-footed ferrets has been reintroduced in the 

Shirley Basin/Medicine Bow Special Management Area. The Shirley Basin/Medicine 

Bow Special Management Area is located immediately east of Seminoe Reservoir and 

north of the Medicine Bow River arm of Seminoe Reservoir. The physical barrier 

imposed by Seminoe Reservoir and the Medicine Bow River precludes any potential 

movement of ferrets from this reintroduced population into the SRPA. 

In Wyoming, prairie dog colonies provide essential habitat for black-footed ferrets. 

Ferrets depend almost exclusively on prairie dogs for food and they also use prairie dog 

burrows for shelter, parturition, and raising young (Hillman and Clark 1980, Fagerstone 

1987). Within the SRPA, white-tailed prairie dog towns represent potential habitat for 

black-footed ferret. According to USFWS guidelines (1989), white-tailed prairie dog 

towns or complexes greater than 200 acres represent potential habitat for black-footed 

ferrets. A town complex is defined as two or more neighboring towns each less than 7 

kilometers from the other. A number of towns meeting these criteria within the Pilot 

Project Area and along the related gas gathering pipeline and access road were 

identified and surveyed for ferrets by TRC (2002a, 2002b). The results of these surveys 

were negative. It is expected that other white-tailed prairie dog towns or complexes of 

towns within the SRPA would require black-footed ferret clearance surveys prior to 

project development in these areas. The BLM would require avoidance of these towns 

L-7
where possible, but if avoidance is not feasible, clearance surveys for black-footed 

ferrets may be warranted prior to ground disturbing activities within qualifying prairie dog 

colonies. Surveys would be conducted according to the most current USFWS guidelines 

(USFWS 1989 or later). Portions of the SRPA within Townships 23 North and 24 North, 

Range 86 West; Township 22 North, Ranges 84 West and 85 West; and Township 21 

North, Range 84 West have been blocked cleared by the USFWS and surveys for blackfooted ferrets in white-tailed prairie dog colonies within these portions of the SRPA 

would not be required. However, the USFWS may require that prairie dog towns within 

block cleared areas be evaluated for their suitability for reintroduction of black-footed 

ferrets. 

3.1.2 Canada Lynx (Threatened) 

Although Wyoming comprises part of the species’ historic geographical range, no lynx 

sightings have been documented in the SRPA or within a 6-mile perimeter (WYNDD 

2004). In a collaborative effort, the BLM and WYNDD completed a lynx habitat suitability 

map for the State of Wyoming (Beauvais et al. 2001). According to the habitat map, no 

Lynx Analysis Units (LAU) exist within the SRPA, and lands within the SRPA provide low 

to poor quality lynx habitat. Lynx could potentially travel through the SRPA, but this 

likelihood is very low due to a lack of suitable habitat. 

Due to the facts that: (1) the SRPA does not include high elevation lodgepole 

pine/spruce-fir habitat types preferred by this species, (2) the SRPA does not support 

suitable habitat for snowshoe hares, a principal prey for lynx, (3) there are no recorded 

lynx sightings within a 6-mile buffer in either the SRPA (WYNDD 2004), and (4) the 

closest potential habitat is approximately 18 miles to the southeast and 30 miles to the 

south in the Medicine Bow Mountains and Sierra Madre Mountains, respectively, it is 

unlikely that lynx would occur on or near the SRPA and is therefore not discussed further 

in this document. 

3.1.3 Preble’s Meadow Jumping Mouse (Threatened) 

In Wyoming, Preble’s meadow jumping mouse is found within riparian habitat corridors 

east of the Laramie Range Mountains and south of the North Platte River (USFWS 

L-8
2004a). A petition to delist this species is currently being evaluated by the USFWS. The 

SRPA is located more than 75 miles west of the known distribution of the Preble’s 

meadow jumping mouse, and this 

species is not expected to occur on the project area. Therefore, Preble’s meadow 

jumping mouse is not discussed further in this document. 

3.1.4 Bald Eagle (Threatened) 

Summer nesting habitat for this species consists of large trees, cliffs, or sheltered 

canyons associated with preferred food sources that consist of fisheries or waterfowl 

concentration areas along large rivers, lakes, or reservoirs. During the non-breeding 

season (fall and winter), bald eagles forage along rivers with open water as well as over 

uplands with big game carrion or prairie dog populations. Potential winter roosting sites 

are generally associated with large trees protected from the weather along open water 

portions of rivers or on lakes and reservoirs where waterfowl are available as prey. 

Potential foraging, perching, and nesting habitat for bald eagle exists along the North 

Platte River within the SRPA. 

Although there are no records of nesting or winter roosting use along this segment of the 

North Platte River (WYNDD 2004), incidental observations made by BLM biologists 

indicate a possible nesting attempt by a bald eagle pair along the North Platte River near 

Seminoe Reservoir. Cedar Creek biologists’ observation of an adult and immature bald 

eagle in cottonwood trees near the North Platte River (SW 1/4, Section 10, T. 22 N., R. 

85 W.) in August 2003 also provided indirect evidence of possible nesting by bald eagles 

somewhere along this segment of the North Platte River. 

3.1.5 Yellow-billed Cuckoo (Candidate) 

The yellow-billed cuckoo is a Neotropical migrant that winters in South America and 

breeds from southeast Canada, throughout most of the United States (except the 

northern Great Plains to the northwest coast) and northern Mexico (Payne 1997). In 

North America, the cuckoo population is divided into two subspecies. The population 

west of the Continental Divide is considered the Western or California subspecies and 

L-9
the population east of the Continental Divide is the Eastern subspecies. Trends 

developed from Breeding Bird Survey (BBS) data indicate that the yellow-billed cuckoo 

is declining throughout its range, and the most dramatic declines have been associated 

with the Western subspecies. As a result, the yellow-billed cuckoo has twice been 

petitioned as an endangered species pursuant to the Endangered Species Act (ESA). 

The Southwest Region of the U.S. Fish and Wildlife Service rejected the first petition 

submitted in 1987. The second petition was submitted in 1998 and called for the listing 

of cuckoos west of the Continental Divide as a subspecies or a geographically, 

morphologically, behaviorally, and ecologically distinct population from cuckoos east of 

the Continental Divide. In July 2001, the USFWS concluded that the petitioned action 

was warranted but precluded by higher priority listing actions. Currently, the yellowbilled cuckoo is considered a candidate species. 

The last record of a yellow-billed cuckoo being detected on a BBS route in Wyoming was 

from 1995 (USGS Patuxent Wildlife Research Center 2004). The yellow-billed cuckoo is 

a BLM sensitive species throughout Wyoming, and it may be found in cottonwood/ 

riparian habitats below 7,000 feet and in urban areas throughout the state (WGFD 

1999). In Wyoming, it is thought to prefer cottonwood stands for foraging and willow 

thickets for nesting. Stands of narrow-leaf cottonwoods along the North Platte River 

near Seminoe Reservoir may represent potential foraging habitat for yellow-billed 

cuckoo, although well-developed willow thickets are generally lacking probably because 

of cattle grazing along the river and large fluctuations of reservoir levels. The WYNDD 

(2005, http://uwadmnweb.uwyo.edu/wyndd/) indicates the possible breeding distribution 

of both the western and eastern subspecies of the yellow-billed cuckoo to be outside of 

the SRPA and Carbon County. In addition, the WYNDD (2005, 

http://uwadmnweb.uwyo.edu/wyndd/) indicates there has been only one observation of 

yellow-billed cuckoo in Carbon County since 1982. This observation was near the North 

Platte River upstream of Seminoe Reservoir and was probably of a transient or nomadic 

individual. The WYNND (2004) has no records of this species within the SRPA, and the 

yellow-billed cuckoo has not been documented in southeast Wyoming by Breeding Bird 

Surveys (BBS) conducted by the USGS, Patuxent Wildlife Research Center from 1966 

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through 2003 (Sauer et al. 2004). No further discussion is provided for yellow-billed 

cuckoo in this document. 

3.1.6 Western Boreal Toad (Candidate) 

One of the true toads (Bufo) endemic to Wyoming, the boreal toad occurs in wet areas of 

the foothills, montane, and subalpine zones to 10,500 feet. Boreal toads range from 

Alaska to northern New Mexico in the Rocky Mountains, west to the Pacific coast 

(Baxter and Stone 1992). Along the western periphery of this toad’s range, it may be 

found in relatively dry habitats at elevations down to sea level (Stebbins 1951). This 

toad is generally found near water during the day but may move farther from water to 

forage during the night (Baxter and Stone 1992). This species congregates near water 

bodies to breed from mid-May to July dependent upon seasonal weather and elevation. 

Boreal toads breed in any body of water lacking a strong current and with gradually 

descending banks at some point around the perimeter (Loeffler 1998). Egg placement is 

usually in shallows where the thermal effects of the sun are optimized (Loeffler 1998). 

Available evidence indicates that females may disperse over greater distances and into 

drier habitats than the males (Loeffler 1998). Recent studies of toads by the Colorado 

Department of Wildlife (CDOW) indicate that male toads remain within 300 meters of 

breeding sites, while females can move up to 3 to 4 miles from breeding areas (Jones 

1999). Selected upland habitats for both males and females include aspen and conifer 

habitats with rocky areas or ground squirrel holes where toads seek refuge in rock 

crevices or rodent burrows to avoid temperature extremes and desiccation. 

In Wyoming, this species is restricted to mountains and foothills in areas having 

relatively moist conditions. It inhabits the central and western mountain ranges but has 

not been observed in the Bighorn Mountains or the Black Hills (Baxter and Stone 1992). 

The range for boreal toads is thought to encompass the North Platte River and Seminoe 

Reservoir (Baxter and Stone 1992), and the Wyoming Species Atlas (WGFD 1999) 

indicates sightings within Carbon County. However, no sightings of this species within 

six miles of the project area have been reported (WYNDD 2004). It appears that habitat 

within the majority of the SRPA is too arid for this species to persist and breed. Also, 

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suitable breeding habitat, shallows with slow-moving water, is generally lacking along 

the North Platte River and the banks of Seminoe Reservoir. 

3.1.7 Wyoming Toad (Endangered) 

The Wyoming toad was historically associated with floodplain ponds along the Big and 

Little Laramie Rivers in Albany County (Baxter and Stone 1992). Currently, the 

Wyoming toad is only known to occur at Mortenson Lake National Wildlife Refuge. 

However, reintroduction efforts are underway in other portions of its former range. The 

Wyoming toad did not historically, and does not currently occur on or near the SRPA and 

is therefore not discussed further in this document. 

3.1.8 Blowout Penstemon (Endangered) 

The Wyoming Natural Diversity Database ranking for blowout penstemon is G1/S1, 

indicating this plant is critically imperiled because of extreme rarity (5 or fewer 

occurrences) at both the global and state levels (WYNDD 2004). Blowout penstemon is 

probably the rarest plant species native to the Great Plains (NGPC 2002). The species is 

most common in the open, sandy habitats of wind-excavated depressions (blowouts) in 

dune tops. In Wyoming, the species has also been documented on very steep, unstable 

sand dunes (Fertig 2001). Within these limited habitats, this short-lived perennial 

frequently occurs in large, multi-stemmed clumps. In June and July, when in bloom in 

Wyoming, its lavender-purple flowers stand out against other sparse vegetation found in 

and around sandy blowouts. In addition to features of its leaves and flowers, blowout 

penstemon’s lavender or vanilla-like fragrance distinguishes it as only one of two 

fragrant species of the 300 penstemons in the world (NGPC 2002). 

Blowout penstemon is a regional endemic of the Sand Hills in Nebraska and the Great 

Basin Divide in Carbon County, Wyoming and is known from 15 extant occurrences 

rangewide. Two of these occurrences are located in Wyoming in northwest Carbon 

County in the Ferris and Seminoe Mountains. These two sites occupy approximately 80 

acres within a 5 square mile area (Fertig 2001). Rangewide this species occurs on 

sparsely vegetated shifting sand dunes and wind eroded blowout depressions. In 

Wyoming, blowout penstemon typically grows on sandy aprons or steep sandy slopes at 

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the base of granitic or sedimentary mountains or ridges at elevations ranging from 6,680 

to 7,440 feet. 

Blowout penstemon was not observed by any of the vegetation surveys conducted in the 

SRPA (HydroGeo 2004; TRC 2001). Several steep, sparsely vegetated, sandy slopes 

on the lee (east) side of ridges in the lower portion of Mountain Lion Draw were 

surveyed, but no populations of blowout penstemon were located (HydroGeo 2004). 

There are no known active sand dunes or areas of potential habitat for blowout 

penstemon in the SRPA and based on known distribution and habitat characteristics for 

blowout penstemon, this species is not likely to occur in the SRPA. 

3.1.9 Ute Ladies’-tresses Orchid (Threatened) 

Ute ladies’-tresses orchid is a perennial, terrestrial orchid with stems 8 to 20 inches tall, 

and flowers consisting of white or ivory flowers clustered into a spike arrangement at the 

top of the stem. The plant blooms mainly from late July through August; however, 

depending on location and climatic conditions, it may bloom in early July or still be in 

flower as late as early October. Habitat for Ute ladies’-tresses orchid can occur in major 

riparian corridors subject to fluvial erosion/deposition, or more ideally, in moist to very 

wet meadows along streams. It has also been found in abandoned stream meanders 

that still have ample ground water, near springs, and lakeshores. The habitat on which 

the species depends has been drastically modified by urbanization, agriculture, and 

development (description adapted from NatureServe 2004). 

Ute ladies’-tresses orchid was designated as threatened in 1992 when it was only known 

from Colorado, Utah, and Nevada. Since that time, it has been found in Wyoming, 

Montana, Nebraska, and Idaho (NatureServe 2004), and a petition to delist this species 

is currently being evaluated by the USFWS. The known locations of the species in 

Wyoming include Converse, Goshen, Laramie, and Niobrara Counties. Ute ladies’­

tresses orchid was not observed by any of the vegetation surveys conducted in the 

SRPA (HydroGeo 2004; TRC 2001). Although suitable habitat for Ute ladies’-tresses 

orchid may exist along the North Platte River, the SRPA is outside of the known 

occurrences of this species and its presence is unlikely. 

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3.1.10 Colorado Butterfly Plant (Threatened) 

The Colorado butterfly plant is a short-lived perennial herb that typically occurs on 

subirrigated soils on level or slightly sloping floodplains and drainage bottoms at 

elevations of 5,000-6,400 feet (Fertig 2000). The species is often found a short distance 

from meandering stream channels. This species is known to occur in Laramie County in 

southeastern Wyoming, in southwestern Nebraska and in northeastern Colorado. This 

species is not known and is not expected to occur on or near the SRPA and is therefore 

not discussed further in this document. 

3.2 Platte River Species 

The SRPA is within the Platte River drainage basin. According to the USFWS (USFWS 

2004), water depletion in the Platte River system may affect and is likely to adversely 

affect the species addressed in this section. These species and their habitats are not 

found within the SRPA, but they could be adversely affected if actions within the SRPA 

result in downstream water depletions. Although none of the Seminoe Road Project 

would result in water depletions in the Platte River System, there is the potential for 

water quality impacts to the system as a result of produced water discharge. 

3.2.1 Whooping Crane (Endangered) 

Critical habitat for the whooping crane many miles downstream of the SRPA and 

Wyoming is located along the Platte River floodplain between Lexington and Dehman, 

Nebraska (Federal Register 1978). Whooping crane habitat consists of large expanses 

of wetlands that provide suitable food (insects, crayfish, frogs, small fish) and open 

expanses near wetlands for nightly roosting (Federal Register 1978). 

3.2.2 Interior Least Tern (Endangered) 

The interior least tern nests on unvegetated sand-pebble beaches and islands of large 

reservoirs and rivers. Interior least terns avoid areas where relatively thick vegetation 

provides cover for potential predators. No habitat for the interior least tern is found on 

the SRPA or in Wyoming, but habitat is located downstream along the Platte River in 

Nebraska (USFWS 1990). 

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3.2.3 Piping Plover (Threatened) 

Critical habitat for the piping plover includes prairie alkali wetlands and surrounding 

shoreline, including 200 feet of uplands above the high water mark; river channels and 

associated sandbars, and islands; reservoirs and their sparsely vegetated shorelines, 

peninsulas, and islands; and inland lakes and their sparsely vegetated shorelines and 

peninsulas (Federal Register 2002). Critical habitat for the species is downstream of the 

SRPA and Wyoming in Nebraska beginning at the Lexington Bridge and extending to the 

Platte’s confluence with the Missouri River 252 mi (405.5 km) downstream (Federal 

Register 2002). Open shorelines and sandbars of rivers, large reservoirs, alkali 

wetlands, lakes and rivers provide suitable breeding habitat for the piping plover. 

3.2.4 Eskimo Curlew (Endangered) 

The Eskimo curlew migrates from wintering grounds in the pampas of Argentina, 

northward through Central America and the central Great Plains of North America to 

breeding grounds in northern Canada and Alaska (Gollop et al. 1986). The spring 

migration route passes through Nebraska, but not Wyoming (Gollop et al. 1986), where 

the birds may stopover along the Platte River. In the fall they migrate eastward to 

Labrador, then south over the Atlantic Ocean back to South America (Gollop et al. 

1986). Habitat for the Eskimo curlew includes grasslands, tundra, burned prairies, 

plowed fields, marshes, mudflats, meadows, and pastures. Burned prairies and 

marshes may be attractive during migration (Gollop et al. 1986). The loss of prairie 

habitat in North America may have contributed to the decline of the Eskimo curlew, but 

the primary reason for the rarity of the bird was market hunting in the late 1800s and 

early 1900s (Gollop et al. 1986). No suitable habitat for the Eskimo curlew occurs on the 

SRPA, and the species has not been reported within or near the SRPA (WYNDD 2004). 

3.2.5 Bald Eagle (Threatened) 

Aside from this species potential presence within the SRPA, bald eagles are also known 

to nest and forage along downstream portions of the North Platte River and other rivers 

within the Platte River system. Nesting and foraging habitat in the North Platte River 

system is similar to that described for bald eagle under Section 3.1.4. 

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3.2.6 Pallid Sturgeon (Endangered) 

The pallid sturgeon is a native fish found in the Mississippi/Missouri River system. The 

pallid sturgeon is present in the lower Platte River in eastern Nebraska but does not 

occur in the Platte River system in western Nebraska or Wyoming. Suitable habitat for 

the pallid sturgeon consists of large turbid rivers with sand or gravel bottoms. The pallid 

sturgeon is threatened by habitat degradation such as decreased turbidity, which can be 

caused by impoundments. 

3.2.7 Western Prairie Fringed Orchid (Threatened) 

The western prairie fringed orchid is a long-lived perennial herb with stems that can grow 

to 1.2 meters tall from an underground tuber. The plant blooms for about a three-week 

period starting in mid-June in the southern portion of its range to late July in the north. 

Habitat of the western prairie fringed orchid is the western portions of North American 

tall-grass prairie, and it is most commonly observed on moist, calcareous soils, subsaline prairies and sedge meadows (many flooded for a period of 1-2 weeks during the 

year). Published accounts and herbarium records suggest that this plant was 

widespread and perhaps locally common prior to European settlement. Declines are 

due to the extensive and on-going conversion of the tall-grass prairie to agricultural uses 

throughout its range (description adapted from NatureServe 2004). 

The western prairie fringed orchid was designated as a threatened species in its entire 

range in 1989. Within the area covered by this listing, this species is known to occur 

outside of Wyoming in Iowa, Kansas, Minnesota, Missouri, North Dakota, Nebraska, 

Oklahoma, and in Manitoba Province, Canada (NatureServe 2004). 

3.3 Petitioned Species 

The following species that do or may occur on the SRPA have been petitioned for listing 

under the ESA. 

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3.3.1 Pygmy Rabbit 

The former range of the pygmy rabbit was thought to be limited to portions of Idaho and 

Utah until their presence was confirmed in southwest Wyoming (Campbell et al. 1982). 

HWA also documented sightings of pygmy rabbit south of Fontenelle Reservoir in 

southwest Wyoming in eastern Lincoln County and western Sweetwater County in 1994 

(HWA 1994). Pygmy rabbits are limited to areas of dense and tall big sagebrush in 

predominantly sandy soils (Campbell et al. 1982, Clark and Stromberg 1987, Heady et 

al. 2002). The SRPA is well east of the known range of pygmy rabbit, and no pygmy 

rabbit records within 6 miles of the SRPA are listed by the WYNDD (2004). In addition, 

tall, dense stands of sagebrush and friable soils preferred by pygmy rabbit are 

essentially lacking within the SRPA. No further discussion of pygmy rabbit is provided in 

this document. 

3.3.2 Columbian Sharp-tailed Grouse 

The USFWS was petitioned on October 14, 2004 to list the Columbian sharp-tailed 

grouse under the Endangered Species Act (ESA) because of population declines over 

much of the species’ range. The BLM has also placed the Columbian sharp-tailed 

grouse on the BLM Wyoming State Director’s Sensitive Species List (BLM 2002). It is 

one of six sub-species of sharp-tailed grouse found in North America. Habitat types 

associated with the distribution of the species in the northwestern United States include 

sagebrush-bunch grass, meadow-steppe, mountain-shrub, and riparian zones (Giesen 

and Connelly 1993). Reductions in these native vegetation types due to agricultural 

practices and livestock grazing are believed to be the primary causes of population 

declines since the turn of the 20th century. Suitable habitat for Columbian sharp-tailed 

grouse is essentially lacking within or near the SRPA, and there are no records of this 

species presence or breeding activity (leks) in or within 2 miles of the SRPA. No further 

discussion of Columbian sharp-tailed grouse will be provided in this document. 

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4.0 DIRECT AND INDIRECT IMPACTS OF THE PROPOSED ACTION AND 

DETERMINATION OF EFFECTS FOR LISTED SPECIES 

Although the total acres of wildlife habitat that would be disturbed under the action 

alternatives is known, the distribution of this disturbance will not be known until actual 

well locations are determined. Therefore, in order to assess the direct and indirect 

impacts of the proposed project, it was assumed that any section of land may potentially 

be developed at the level of four locations per section under the action alternatives. 

4.1 Proposed Action 

Under the Proposed Action approximately 6,174 acres of wildlife habitat would be 

sequentially disturbed over 30 years. However, with concurrent reclamation of disturbed 

habitats the total unreclaimed disturbance area at any given point in time would never 

equal the sequential total. Under the action alternatives, reclamation would reduce 

impacts to 2,349 acres or 1.4 percent of the SRPA by the end of the development phase 

of the project. Timing of reclamation and climatic conditions will influence reclamation 

success. 

4.1.1 Threatened, Endangered, Proposed, and Candidate Species 

Black-footed Ferret. White-tailed prairie dog towns are known to occur in areas of 

suitable habitat throughout the SRPA. It is likely that some of these towns or complexes 

of towns, outside of the block clearance area would meet the requirements for 

consideration as black-footed ferret habitat. Development of the Proposed Action may 

result in direct disturbance of some portions of these prairie dog towns or complexes. 

Surveys for black-footed ferrets would be required prior to ground disturbing activities 

within prairie dog towns or town complexes determined to provide potential habitat for 

black-footed ferret. Surveys would be conducted according to the most current USFWS 

guidelines (USFWS 1989 or later). Surveys would not be required for white-tailed prairie 

dog colonies within the “block clearance” portion of the SRPA. However, these prairie 

dog colonies may analyzed as potential black-footed ferret reintroduction sites. 

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x

Consultation with the USFWS would be initiated prior to surveys being conducted. If 

black-footed ferrets or sign are found, no project related disturbance would occur within 

the prairie dog complex, and previously authorized project related activities on-going in 

such towns or complexes would be suspended immediately. The USFWS would be 

notified within 24 hours if a black-footed ferret or their sign is observed. As long as 

surveys for black-footed ferrets are conducted in suitable prairie dog towns or town 

complexes before they are disturbed and the prescribed avoidance measures (listed in 

the Coordination Measures section) are applied, impacts to the black-footed ferret are 

unlikely to occur. Based upon the analyses of the proposed project, the current and 

potential status of the species in the project area, other land use activities in the area, 

and incorporation of the coordination measures recommended in this BA, it is concluded 

that implementation of the Proposed Action may affect but is not likely to adversely 

affect the black-footed ferret. 

Bald Eagle. Potential nesting habitat for bald eagles is located only in proximity to the 

North Platte River. Bald eagles may utilize other portions of the SRPA for foraging 

during winter months because the majority of the SRPA is classified as pronghorn 

winter/yearlong range. (Winter/yearlong range is defined by the WGFD as range that is 

used yearlong, but during winter, has a substantial influx of animals from other seasonal 

ranges.) In addition, a small portion of crucial winter/yearlong mule deer range is 

located within the southwest corner of the SRPA near the North Platte River. Upland 

habitat use by bald eagles within the project area would probably be limited to winter 

scavenging forays. Few trees large enough for eagle roosting or nesting exist on the 

project area, and these are found along the North Platte River. In order to preclude the 

potential for any disturbance of bald eagle nest or winter roost sites, the following 

mitigation measures would be employed. 

Before any project disturbance occurs within 1 mile of suitable tree stands along 

the North Platte River, appropriate surveys would be conducted, during the 

appropriate season, to determine if any winter roost or nest sites exist within 1 

mile of proposed disturbance sites. The 1-mile requirement could be reduced 

depending on intervening topography between suitable habitat and potential 

disturbance sites. Surveys would be coordinated with the USFWS. 

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x If any bald eagle winter roost or nest sites are located, appropriate buffers and 

mitigation measures will be developed in consultation with the USFWS to 

preclude any impacts to these sites. At a minimum, no disturbance activities 

would be permitted within 1 mile of winter roost or nest sites during the period of 

occupation of these sites. No permanent surface disturbance would also be 

permitted within 1,200 feet of a bald eagle nest site. 

The potential for vehicle collisions with big game would increase as a result of increased 

vehicular traffic associated with the presence of construction crews and activities in the 

project area. Because bald eagles commonly feed on carrion, particularly during the 

winter months, the presence of road-killed big game carcasses on and adjacent to 

Seminoe Road and other access roads could serve as an attractant to foraging bald 

eagles. Eagles feeding on these carcasses are in danger of being struck by moving 

vehicles. Any increase in the death rate of bald eagles from vehicular collisions would 

constitute a significant impact. Because the potential for an increase in the incidence of 

big game-vehicle-eagle encounters exists, measures to avoid and/or reduce such 

incidents would be taken. Such measures shall include the following. 

x Regular drivers undergo training describing the circumstances under which 

vehicular collisions with bald eagles are likely to occur and the measures that can 

be employed to minimize them, including reduced speeds 

x Prohibition of unnecessary off-site activities of operational personnel and inform 

all project employees of applicable wildlife laws and penalties associated with 

unlawful take and harassment. 

x Removal of vehicle-killed carcasses from the ROWs of access roads on the 

project area to eliminate the exposure of carrion-feeding eagles to the threat of 

being struck by vehicles. 

x Operators will internally enforce existing drug, alcohol, and firearms policies. 

x Posting of a 25 mph speed limit on access roads controlled by Dudley. 

Based upon the analyses of the proposed project, the current and potential status of the 

species in the project area, other land use activities in the area, and incorporation of the 

coordination measures recommended in this BA, it is concluded that implementation of 

the Proposed Action may affect but is not likely to adversely affect the bald eagle. 

Western Boreal Toad. In Wyoming, this species is restricted to mountains and foothills 

in areas having relatively moist conditions. It inhabits the central and western mountain 

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ranges but has not been observed in the Bighorn Mountains or the Black Hills (Baxter 

and Stone 1992). The range for boreal toads is thought to encompass the Muddy Creek 

watershed (Baxter and Stone 1992), and the Wyoming Species Atlas (WGFD 1999) 

indicates sightings within both Sweetwater and Carbon counties. However, no sightings 

of this species within 6 miles of the project area have been reported (WYNDD 2004). 

This species has not been documented within the SRPA. Habitat within the majority of 

the SRPA is too arid for this species to persist and thrive, but it may occur in isolated 

areas where habitat is suitable along the North Platte River. Three BLM standard 

stipulations would limit project development near the North Platter River or Seminoe 

Reservoir. They are as follows. 

x No surface occupancy or drilling within 1,000 feet of the Seminoe Reservoir 

maximum water surface, which has been determined to be at an elevation 

6357.00 feet. (Only applies where the United States owns 100 percent of the fee 

mineral interest.) 

x No surface occupancy within 500 feet of the normal high water line of any and all 

live streams. (Only applies where the United States owns 100 percent of the fee 

mineral interest.) 

x No surface occupancy within 0.25 mile of the North Platte River unless the 

operator and BLM arrive at an acceptable plan for mitigation of anticipated 

impacts. 

Based on these stipulations, it is unlikely the BLM would permit project disturbance 

activities within riparian or wetland habitats along the North Platte River within the 

SRPA. In the event that disturbance within riparian or wetland habitats is permitted by 

the BLM, the BLM would require that surveys for western boreal toad be completed. 

Therefore, it is unlikely that the Proposed Action would impact the western boreal toad or 

lead to its listing as threatened or endangered. 

Blowout Penstemon. Potential habitat for blowout penstemon is not present within the 

SRPA since there are no active sand dune areas known to be present. Site-specific field 

surveys required by the BLM for each development phase of the proposed project would 

ensure that suitable habitat for blowout penstemon would not be affected by project 

development. In the unlikely event that suitable habitat or a population of this species is 

located within the SRPA, specific mitigation measures would be developed to preclude 

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any impacts to this species or its preferred habitat. Based upon the analyses of the 

proposed project, the current status of this species, other land use activities in the area, 

and incorporation of the coordination measures recommended in this BA, it is concluded 

that implementation of the Proposed Action would have no effect on blowout 

penstemon. 

Ute Ladies’-tresses. Suitable habitat for Ute ladies’-tresses orchid may exist along the 

North Platte River, but the SRPA is well outside of the known populations of this species 

and its presence is unlikely. As indicated under the preceding section on boreal toad, 

three BLM standard stipulations would limit project development near the North Platter 

River or Seminoe Reservoir. Based on these stipulations, it is unlikely the BLM would 

permit project disturbance activities within riparian or wetland habitats along the North 

Platte River within the SRPA, and, therefore, it is unlikely that project implementation 

would impact Ute ladies’-tresses orchid. 

Based upon the analyses of the proposed project, the current and potential status of the 

species in the project area, other land use activities in the area, and incorporation of the 

coordination measures recommended in this BA, it is concluded that implementation of 

the Proposed Action would have no effect on Ute ladies’-tresses orchid. 

4.1.2 Platte River Species 

The whooping crane, interior least tern, piping plover, Eskimo curlew, bald eagle, pallid 

sturgeon, and western prairie fringed orchid are all found considerably downstream of 

the SRPA along the Platte River in Nebraska. No habitat for any of these species, 

except bald eagle (see Section 4.1.1) occurs on the SRPA and they are not likely to 

occur there. The USFWS has taken the position in its Section 7 Consultations that 

federal actions resulting in water depletion to the Platte River system may affect and are 

likely to adversely affect these species. However, the action alternatives would not 

result in any water depletions in the Platte River system, and Alternatives B and C would 

result in added water to the system. Based on the hydrologic analyses presented in 

Section 3.5.3 of the Draft EIS (see Appendix A), project development would result in only 

minor increases in SAR values in Seminoe Reservoir and would not have any impact on 

water quality in downstream portions of the North Platte River or the Platte River system. 

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In addition, project development would result in an increase in water supply to Seminoe 

Reservoir and the North Platte River and would not result in any water depletions in 

downstream portions of the Platte River system. Therefore, implementation of the 

Proposed Action would have no effect on threatened or endangered species in the 

Platte River system. 

4.2 Alternative A – No Action 

Under the No Action Alternative, there would be no additional development or production 

activities beyond those permitted under the existing Pilot Project, and there would be no 

additional effects to wildlife habitat or wildlife species. Therefore, this alternative would 

have no effect on threatened, endangered, proposed, candidate, or petitioned species 

in the SRPA. 

4.3 Alternative C (Pipeline to Reservoir) 

The Pipeline to Reservoir alternative (Alternative C) would be similar to the Proposed 

Action except that produced water would be piped directly to the North Platte River and 

Seminoe Reservoir rather than being released down existing ephemeral drainages. 

Therefore, potential impacts to threatened, endangered, proposed, candidate, or 

petitioned species in the SRPA would be the same as those discussed for the Proposed 

Action in Section 4.1. 

4.4 Alternative D (Underground Injection) 

The Underground Injection alternative (Alternative D) is the same as the Proposed 

Action except that produced water would not be discharged into the North Platte River or 

Seminoe Reservoir. Therefore, potential impacts to threatened, endangered, proposed, 

candidate, or petitioned species in the SRPA would be the same as those discussed for 

the Proposed Action in Section 4.1 except there would be water discharge added to the 

Platte River system. 

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5.0 CUMULATIVE IMPACTS


The cumulative impact analysis (CIA) approach is used to evaluate the influences of 

recent, past, present, and reasonably foreseeable future human developments on the 

local wildlife resources. This approach examines impacts associated with a proposed 

project in context with all other past and future developments, whether or not they are 

related. It also allows the wildlife manager and land management agency to evaluate 

impacts on a broader scale. However, one of the inherent problems associated with CIA 

is that there are no definable limits as to the exact boundary or size of the geographic 

area to be considered. The BLM recommends evaluating cumulative impacts on a 

watershed basis for natural resources related to watershed function and stability. 

However, with special concern wildlife and plant species, there are no clear, definable 

limits as to the most appropriate area to be considered in CIA. Moreover, complete 

information on the distribution, population levels, and habitats of specific species of 

concern is lacking and most accounts of these species are incidental in nature. 

During the construction phase, the Proposed Action would disturb 6,174 acres. 

Disturbance areas within the SRPA would be reduced upon reclamation of pipeline 

ROWs, unused portions of the drill pad, portions of roads, and ancillary facility 

disturbances during the production phase for each alternative, resulting in long-term 

disturbance of 2,349 acres under the Proposed Action. 

Black-footed Ferret 

Provided that avoidance measures outlined in this document are followed, the potential 

for an incremental increase in cumulative impacts due to the implementation of the 

Proposed Action may affect the black-footed ferret but is not likely to adversely affect 

the black-footed ferret. 

Bald Eagle 

Provided that avoidance measures outlined in this document are followed, the potential 

for an incremental increase in cumulative impacts due to the implementation of the 

Proposed Action may affect but is not likely to adversely affect the bald eagle. 

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Western Boreal Toad 

Implementation of the Proposed Action is not expected to contribute to cumulative 

impacts upon the western boreal toad due to a lack of confirmed occurrences of the 

species within the SRPA and protection of wetland habitat along the North Platte River. 

Blowout Penstemon 

Implementation of the Proposed Action is not expected to contribute to cumulative 

impacts upon blowout penstemon due to a lack of potential habitat and confirmed 

occurrence of the species within the SRPA. 

Ute Ladies’-tresses 

Implementation of the Proposed Action is not expected to contribute to cumulative 

impacts upon Ute ladies-tresses because the SRPA is outside of the known range of this 

species. 

Platte River Species 

No habitat for any of these species occurs in the SRPA, and they would not occur there. 

The Proposed Action would not have any impact on water quality in downstream 

portions of the North Platte River or the Platte River system. In addition, Alternatives B 

and C would result in an increase in water supply to Seminoe Reservoir and the North 

Platte River and would not result in any water depletions in downstream portions of the 

Platte River system. Therefore the Proposed Action would have no cumulative impacts 

on listed species in the Platte River system. 

6.0 COORDINATION MEASURES TO AVOID OR REDUCE ADVERSE IMPACTS 

The following procedures will be implemented to eliminate or substantially reduce 

potential adverse effects of the proposed project to threatened, endangered, proposed, 

candidate, and petitioned species that may occur on or near the SRPA or that may be 

impacted by the project. 

L-25
x If disturbance of prairie dog colonies located within non-block clearance areas 

cannot be avoided, black-footed ferret surveys will be conducted in town or town 

complexes according to USFWS guidelines (USFWS 1989) if the affected towns 

meet the survey requirements. Towns or colonies within block-clearance areas 

will be analyzed for their suitability as potential reintroduction sites for blackfooted ferrets. 

x Well pads and disturbances shall be placed outside of prairie dog colonies where 

feasible. 

x Should black-footed ferrets be documented in a prairie dog complex located 

within the project area, impacts to the species or its habitat will be completely 

avoided, and previously authorized project-related activities on-going in the 

prairie dog complex shall be suspended immediately. 

x The BLM and operators shall conduct educational outreach to employees 

regarding the nature, hosts, and symptoms of canine distemper, and its effects 

on black-footed ferrets, focusing attention on why pets would be prohibited from 

work sites. 

x All suspected observations of black-footed ferrets, their sign, or carcasses on the 

SRPA, however obtained, shall be promptly (within 24 hours) reported to the 

BLM and USFWS. 

x Before any project disturbance occurs within 1 mile of suitable tree stands along 

the North Platte River, appropriate surveys would be conducted to determine if 

any winter roost or nest sites exist within 1 mile of proposed disturbance sites. 

Surveys would be coordinated with the USFWS. 

x If any bald eagle winter roost or nest sites are located appropriate buffers and 

mitigation measures will be developed in consultation with the USFWS to 

preclude any impacts to these sites. At a minimum, no disturbance activities 

would be permitted within 1 mile of winter roost or nest sites during the period of 

occupation of these sites. 

x All drivers shall undergo a training session describing the type of wildlife in the 

area that are susceptible to vehicular collisions in order to reduce the potential for 

vehicle-big game collisions and subsequent jeopardy to bald eagles feeding on 

road-killed carrion. The circumstances under which such collisions are likely to 

occur, and the measures that could be employed to minimize them shall be 

discussed. Reduced speed limits shall be implemented to reduce potential for 

vehicle-wildlife collisions. 

x Carcasses shall be removed from access roads, shoulders, and the ROWs to 

minimize bald eagle exposure to vehicle collisions. 

x Appropriate sedimentation, erosion control, and produced water control 

measures included in the Record of Decision will be implemented to avoid 

L-26 
x

changes in water quality or quantity in the streams within the SRPA. Water 

discharge into Seminoe Reservoir will be regulated by the Wyoming Department 

of Environmental Quality (DEQ). 

Construction equipment fueling and servicing areas shall be located at least 150 

feet from surface water drainages and riparian areas. 

6.1 Standard BLM Stipulations 

Several Standard BLM Stipulations would apply to the SRPA. They are listed below in 

no particular order. 

x Prior to surface occupancy, surveys are required to ensure no threatened, 

endangered, candidate, proposed, or other special status species are present. 

Exploration and development proposals may be limited, or modifications 

required, if activity is planned within the boundaries of a threatened, endangered, 

candidate, or other special status plant/animal species as it then exists. 

x No surface occupancy or drilling within 1,000 feet of the Seminoe Reservoir 

maximum water surface, which has been determined to be at an elevation 

6357.00 feet. (Only applies where the United States owns 100 percent of the fee 

mineral interest.) 

x No surface occupancy within 500 feet of the normal high water line of any and all 

live streams. (Only applies where the United States owns 100 percent of the fee 

mineral interest.) 

x Surface occupancy is restricted or prohibited in big game crucial winter range 

(November 15 – April 30) unless the operator and BLM arrive at an acceptable 

plan for mitigation of anticipated impacts. Construction and other activities 

potentially disruptive to wintering wildlife are prohibited during the period of 

November 15 to April 30 for the protection of big game winter habitat. 

x No surface occupancy within 0.25 mile of the North Platte River unless the 

operator and BLM arrive at an acceptable plan for mitigation of anticipated 

impacts. 

x No surface occupancy within 0.25 mile of sage grouse leks unless the operator 

and BLM arrive at an acceptable plan for mitigation of anticipated impacts. 

Construction and other activities potentially disruptive to strutting and nesting 

sage grouse are prohibited within a 2-mile radius of active leks during the period 

of March 1 to June 30 for the protection of sage grouse nesting areas. 

x Surface occupancy will be restricted or prohibited within Raptor Concentration 

areas unless the operator and BLM arrive at an acceptable plan for mitigation of 

anticipated impacts. No roads or development within 0.5-1.0 of active or inactive 

raptor nest sites. 

L-27
x

x Construction and other activities potentially disruptive to nesting raptors are 

prohibited during the period of February 1 to July 31 for the protection of raptor 

nesting areas. 

x Construction and other activities are prohibited during the reproductive period of 

April 1 to June 30 for the protection of potential mountain plover habitat. 

Construction and other activities within white-tailed prairie dog towns greater than 

200 acres would require informal/formal consultation with the U.S. Fish and 

Wildlife Service. 

7.0 EFFECTS OF THE PROJECT ON THE EXPECTED STATUS 

OF SPECIES IN THE FUTURE 

Provided that the coordination measures described above are implemented, the 

proposed project is not expected to alter the current status of, or result in any decreased 

survival of, any of the species discussed in this document during the project or after 

project completion. 

8.0 REFERENCES CITED 

Baxter, G. T., and M. D. Stone. 1992. Amphibians and Reptiles of Wyoming. Wyoming 

Game and Fish Department, 137pp. 

Beauvais, G.P., D. Keinath, and J. Ratner. 2001. Habitat mapping and field surveys for 

lynx (Lynx Canadensis) on lands administered by the USDI-Bureau of Land 

Management in Wyoming. Wyoming Natural Diversity Database, Laramie, 

Wyoming. 11 pp. Plus appendices. 

Bureau of Land Management (BLM). 2002. BLM Wyoming sensitive species policy and 

list, September 20, 2002. Bureau of Land Management, Cheyenne, Wyoming. 

14pp. 

Bureau of Land Management (BLM). 2005. Draft Environmental Impact Statement for 

the Seminoe Road Gas Development Project. Document in Preparation. BLM, 

Rawlins Field Office. 

Campbell, T.M., T.W. Clark, and C.R. Groves. 1982. First record of pygmy rabbits 

(Brachylagusidahoensis) in Wyoming. Great Basin Naturalist 42:100. 

Clark, T.W. and M.R. Stromberg. 1987. Mammals in Wyoming. University of Kansas 

Museum of Natural History, Public Education Series No. 10. 313pp. 

Fagerstone, K.A. 1987. Black-footed ferret, long-tailed weasel, and least weasel. Pages 

548-573 in M. Novak, J.A. Baker, M.E. Obbard, and B.Mallock, editors. Wild 

L-28
Furbearer Management and Conservation in North America. Ministry of Natural 

Resources, Ontario. 

Federal Register. 1978. Proposed critical habitat for the whooping crane. 

43(160):36588-36590. 

Federal Register. 2002. Designation of critical habitat for the northern Great Plains 

breeding population of the piping plover; final rule. 67(176):57637-57717. 

Fertig, W. 2000. Status Review of the Colorado Butterfly Plant (Gaura neomexicana 

ssp. coloradensis). Prepared for the Wyoming Cooperative Fish and Wildlife 

Research Unit, U.S. Fish and Wildlife. Wyoming Natural Diversity Database, 

Laramie, WY. Retrieved February 6, 2004 from www.uwyo.edu/wyndd. 

Fertig, W. 2001. 2000 survey for blowout penstemon (Penstemon haydenii) in 

Wyoming. A report prepared for the Bureau of Land Management Wyoming State 

Office. Wyoming Natural Diversity Database, University of Wyoming, Laramie. 

Giesen, K. M. and J. W. Connelly. 1993. Guidelines for management of Columbian 

sharp-tailed grouse habitats. Wildl. Soc. Bull. 21:325-333. 

Gollop, J.B. T.W., Barry, and E.H. Iverses. 1986. Eskimo curlew a vanishing species? 

Saskatchewan Natural History Society special publication No. 17. Regina 

Saskatchewan. Northern Prairie Wildlife Research Center Home Page. 

http://www.npwrc.usgs.gov/resource/othrdata/curlew/curlew.htm (Version 16 July 

1997). 

Hall, E.R. and K.R. Kelson. 1959. The mammals of North America. The Ronald Press 

Company, New York. 1083pp. 

Hayden-Wing Associates (HWA). 1994. Wildlife technical report for the Expanded 

Moxa Arch Analysis Area. Unpublished report prepared for the BLM Kemmerer 

Resource Area and Gary Holsan Environmental Planning. 

Heady, L.T., K.I. Gabler, and J.W. Laundre’. 2002. Habitat selection by pygmy rabbits 

in southeast Idaho. Department of Biological Sciences Idaho State University, 

Pocatello, ID 83209. Website: http://www.id.blm.gov/techbuls/01_07/entiredoc.pdf 

Hillman, C.N. and T.W. Clark. 1980. Mustela nigripes. Mammalian Species No. 126. 

3pp. 

HydroGeo, Inc. 2004. Draft 2003 Vegetation Addendum Report, Seminoe Road Gas 

Development Project, Prepared for Bureau of Land Management. 

Jones, M. 1999. Wildlife biologist, CDOW, Fort Collins, Colorado. Personal 

communication with M. Phelan, Cedar Creek Associates, Inc., January 14, 1999. 

L-29
Loeffler, C. (Ed.). 1998. Conservation plan and agreement for the management and 

recovery of the southern Rocky Mountain population of the boreal toad (Bufo 

boreas boreas). Boreal Toad Recovery Team. 66 pp. + appendices. 

NatureServe. 2004. NatureServe Explorer: An online encyclopedia of life [web 

application]. Version 4.0. NatureServe, Arlington, Virginia. Available 

http://www.natureserve.org/explorer. (Accessed: December 10, 2004 ). 

Nebraska Game and Parks Commission (NGPC). 2002. The blowout penstemon: an 

endangered species. http://www.ngp.ngpc.state.us 

Payne, R.B. 1997. Family Cuculidae (Cuckoos). Pp. 508 – 607 in J. del Hoyo, A. 

Elliott, and J. Sargatal (eds.). Handbook of the Birds of the World. Vol. 4. 

Sandgrouse to Cuckoos. Lynx Edicions, Barcelona. 679 pp. 

Sauer, J. R., J. E. Hines, and J. Fallon. 2004. The North American Breeding Bird 

Survey, Results and Analysis 1966-2003. Version 2004.1. USGS Patuxent 

Wildlife Research Center, Laurel, MD. 

Stebbins, R. C. 1951. Amphibians of western North America. University of California 

Press, Berkeley. 539pp. 

TRC .	 2001. Riparian Vegetation Baseline Investigations of Discharge Drainage 

Channels for the Seminoe Road Pilot Project, Carbon County, Wyoming. 

Prepared for Dudley & Associates, LLC. 

TRC. 2002a. Black-footed ferret survey of prairie dog towns 6, 7, 8, 9, 10, 11, 12, 13, 

14, 15, 16, and 18, Seminoe Road Coalbed Methane Pilot Project pipelines, Carbon 

County, Wyoming. Unpublished report prepared by TRC, Laramie, Wyoming. 

March 2002. 7 pp. + appendix. 

TRC. 2002b. Black-footed ferret survey, Seminoe Road Coalbed Methane natural gas 

gathering pipeline and access road project, Carbon County, Wyoming. Unpublished 

report prepared by TRC, Laramie, Wyoming. July 2002. 6 pp. + map & 

appendices. 

U. S. Fish and Wildlife Service (USFWS).	 1989. Black-footed ferret survey guidelines


for compliance with the Endangered Species Act. U.S. Department of the Interior,


Fish and Wildlife Service, Denver, CO and Albuquerque, NM. 15pp.


USFWS. 1990. Recovery plan for the interior population of the least tern (Sterna 

Antillarum). Twin Cities, Minnesota. 90 pp. 

USFWS. 2004a. Threatened, endangered, and proposed species which may occur 

within the Bureau of Land Management, Rawlins Field Office’s area of 

management. March 23, 2004. Fish and Wildlife Service, Cheyenne, Wyoming. 

USGS Patuxent Wildlife Research Center. 2004. North American Breeding Bird Survey 

Internet data set, 15 September 2004 (http://www.pwrc.usgs.gov/bbs/retrieval/). 

L-30
Wyoming Game and Fish Department (WGFD). 1999. Atlas of birds, mammals, 

reptiles and amphibians in Wyoming. Wyoming Game and Fish Department, 

Biological Services Section, Lander, WY. 190pp. 

Wyoming Natural Diversity Database (WYNDD). 2004. Data compilation for Cedar 

Creek Associates, Inc. and HydroGeo for the Seminoe Road Project Area, 

completed May 28, 2004. Unpublished reports. Wyoming Natural Diversity 

Database, University of Wyoming, Laramie, Wyoming. 

Wyoming Natural Diversity Database (WYNDD). 2005. 

http://uwadmnweb.uwyo.edu/wyndd/ 

L-31
Appendix M 

Cultural Resources Management Plan 
November 2005 Draft Environmental Impact Statement

Appendix M – Cultural Resources Management

Contents

1.0 Program Objectives................................................................................................... M-1


2.0 Identification of Cultural Resources. ................................................................... M-1


3.0 BLM Jurisdiction on Privately Owned and/or Split Estate Lands.................. M-2


4.0 Evaluation of Cultural Resource Sites .................................................................. M-3


5.0 Standard Protective Measures............................................................................... M-4


6.0 Cultural Resource Laws and Regulations ............................................................ M-4


Seminoe Road Gas Development Project M-i 
November 2005 Draft Environmental Impact Statement

1.0 Program Objectives 

The BLM has developed a cultural resources program designed to inventory, evaluate, and 

manage cultural resources on BLM-administered public land and in areas of BLM responsibility. 

The BLM management of cultural resources (archaeological, historic, and socio-cultural 

properties) is in accordance with the provisions of the National Historic Preservation Act (NHPA) 

of 1966, as amended, and other applicable legislation. 

2.0 Identification of Cultural Resources 

The BLM requires cultural resource inventories for actions involving public lands and/or federal 

mineral estate that include surface disturbance as a part of the action. Three classes of inventory 

have been established; Class III is the most intensive and the most often required for areas that 

have not been subjected to previous inventories or have been subjected to complete surface 

disturbance in the past. 

Class I inventories are completed with the use of existing data from cultural resource inventory 

files maintained by both the BLM and the Wyoming State Historic Preservation Office (SHPO). 

Class I inventories serve to identify known properties and are used to determine if more intensive 

inventory of specific areas is appropriate. This determination is made in consultation with the 

Wyoming SHPO and often results in the completion of Class II or Class III inventories. 

Class II inventories are statistically based sample surveys designed to aid in characterizing the 

probable density, diversity, and distribution of cultural properties in the area, to develop and test 

predictive models, and to answer appropriate research questions. Within individual sample units, 

survey aims, methods, and intensity are the same as those applied in Class III survey. Class II 

survey may be conducted in several phases, using different sample designs, to improve statistical 

reliability. 

Class III intensive field surveys are conducted by professional archaeologists through pedestrian 

survey of an entire target area. The intent of a Class III inventory is to locate and record all 

historic properties and is consistent with standards in the Secretary of the Interior’s Standards 

and Guidelines for Archaeology and Historic Preservation (48 FR 44716). Class III inventories 

conform to the prevailing professional survey standards for the region involved, provided that the 

regional standards meet or exceed the Secretary’s Standards and Guidelines. Because Class III 

survey is designed to produce a total inventory of the cultural properties observable within the 

target area, once it has been completed no further survey work should be needed in the target 

Seminoe Road Gas Development Project M-1 
Draft Environmental Impact Statement November 2005

area as long as the current standards are met. Areas with a high probability of containing buried 

cultural materials or known cultural materials may require additional work of professional 

monitoring and/or data recovery excavations. Areas that require additional work are analyzed on 

a case-by-case basis, depending on the proposed action and the types of cultural resources 

present in the project area. 

3.0 BLM Jurisdiction on Privately Owned and/or Split Estate Lands 

Class III inventories are generally required before surface-disturbing actions are authorized on 

publicly owned surface lands and/ or on private or state owned surface lands if the proposed 

project could not occur without the use of federally owned lands. If a project requires the use of 

federally owned surface lands as well as privately owned surface lands, there are two authorities 

that require federal agencies to apply the same NHPA Section 106 compliance standards to 

private lands as they do federal lands. The regulations at 36 CFR, Part 800.4(b) require the 

Federal agency to “take the steps necessary to identify historic properties within the area of 

potential effect.” That this includes both Federal and nonfederal lands is implicit throughout the 

statute and the regulations, since the regulatory definition of “area of potential effect is “the 

geographic area or areas within which an undertaking may directly or indirectly cause changes in 

the character or use of historic properties” [36 CFR, Part 800.16(d)]. It makes no distinction 

between Federal and nonfederal lands. More explicit, however, is Executive Order No. 11593, 

entitled “Protection and Enhancement of the Cultural Environment.” Under the EO, Section 1(3) it 

states that all Federal agencies: “...in consultation with the Advisory Council on Historic 

Preservation, institute procedures to assure that Federal plans and programs contribute to the 

preservation and enhancement of non-federally owned sites, structures and objects of historical, 

architectural, or archaeological significance.” 

Split estate lands are defined as those lands where surface ownership has been transferred to 

private landowners from the Federal government but the mineral rights were retained by the 

Federal government. These situations arose either through patent under 1914 amendment to the 

Homestead Act or purchase under the Stock-raising Act of 1916. Each of these Acts also allowed 

for the Federal government to “reenter and occupy so much of the surface...as may be required 

for all purposes reasonably incident to the mining or removal of coal or other minerals.” At the 

time of purchase, the buyer agreed to these terms. Since completing compliance of the NHPA 

Section 106 process is required of a Federal agency by statute and regulation prior to the Federal 

M-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

action, then being able to complete that process is a purpose reasonably incident to the 

extraction of the minerals. 

4.0 Evaluation of Cultural Resource Sites 

The BLM evaluates the significance of cultural resources identified during inventory in 

consultation with the Wyoming SHPO to determine if the resources are eligible for inclusion in the 

National Register of Historic Places (NRHP). Cultural resource properties may be considered 

eligible for listing in the National Register if they meet one or more of the following criteria: 

3⁄4 Criterion A: An historic property is associated with an event or events that have made a 

significant contribution to the broad patterns of America’s History. 

3⁄4 Criterion B: An historic property is associated with the lives of persons significant to our 

past. 

3⁄4 Criterion C: An historic property embodies the distinctive characteristics of a type, period, 

or method of construction, or represents the work of a master, or possesses high artistic 

value or represents a significant and distinguishable entity whose components may lack 

individual distinction. 

3⁄4 Criterion D: An historic property has yielded or may be likely to yield information 


important in prehistory or history. 


Those sites eligible under Criteria A, B, or C require case-by-case consultation in which the 

Wyoming SHPO has 30 days to reply. According to a Programmatic Agreement between the 

Wyoming BLM and the Wyoming SHPO, the BLM has implied concurrence for determining 

eligibility of sites under Criterion D of the NHPA. 

To facilitate evaluation of cultural resource values in Wyoming, the BLM has 

devised guidelines for determining the eligibility of archaeological and historical 

sites and historic trails (BLM Manual 8110.32). The guidelines supplement the 

National Register criteria for evaluation (36 CFR 60.4) and provide consistency 

across the state. Application of the guidelines ensures that significant cultural 

resources are recognized and managed accordingly. 

Seminoe Road Gas Development Project M-3 
Draft Environmental Impact Statement November 2005

Properties that encompass large areas can be deemed to have contributing and noncontributing portions. Contributing portions are seen to retain integrity of the values for 

which the property is considered eligible for the NRHP. Non-contributing portions are 

identified portions of the property, which are not deemed to retain the integrity of values, 

which would render the property eligible for the NRHP. The determination of contributing 

versus non-contributing portions of an eligible property can be made at any time after 

adequate evaluation has been conducted. 

5.0 Standard Protective Measures 

Within the framework described above, the BLM has developed protective measures to minimize 

adverse effects on significant cultural resource values. 

Protective measures are used in response to the actions of BLM programs involving surface 

disturbance. These measures include cultural resource inventories, evaluation of cultural 

resources located during inventory, and mitigation of potential adverse impacts on significant 

cultural resources. Mitigation may include avoidance, data recovery (including excavation), or 

other protective measures. Avoidance is the primary and preferred mitigative measure used to 

protect cultural resources. Consultation with the Wyoming SHPO and the Advisory Council on 

Historic Preservation is required when surface-disturbing actions are expected to adversely affect 

properties eligible for the National Register. An adverse effect to an historic property is defined in 

36 CFR 800.5(1). 

Although Class III inventories are completed before any surface disturbance can begin, the BLM’s 

opportunity to preserve significant cultural resource values in place can be precluded if cultural 

properties are not identified prior to initiation of an action. This generally would result in an 

unanticipated discovery situation. In cases such as this, mitigative actions such as data recovery 

would be implemented. 

6.0 Cultural Resource Laws and Regulations 

American Antiquities Act of 1906 – provides for permits to authorize scholarly use of properties, 

for misdemeanor-level penalties to control unauthorized use, and for presidential designation of 

outstanding properties as national monuments for long-term preservation. 

M-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

National Historic Preservation Act of 1966 – 

3⁄4 Section 106 directs all federal agencies to take into account effects of their undertakings 

(actions and authorizations) on properties included in or eligible for the NRHP. 

3⁄4 Section 110 sets inventory, nomination, protection, and preservation responsibilities for 

federally owned cultural properties. Section 110(c) requires each federal agency to 

designate a Preservation Officer to coordinate activities under the act. 

National Environmental Policy Act of 1969 – establishes national policy for the protection and 

enhancement of the environment, including “important historic, cultural, and natural aspects of 

our national heritage.” 

Executive Order 11593 (“Protection and Enhancement of the Cultural Environment,” 36 F.R. 

8921, May 13, 1971) directs federal agencies to inventory cultural properties under their 

jurisdiction, to nominate to the NRHP all federally owned properties that meet the criteria, to use 

due caution until the inventory and nomination processes are completed, and also to assure that 

federal plans and programs contribute to preservation and enhancement of non-federally owned 

properties. 

Federal Land Policy and Management Act of 1979 – directs the BLM to manage public lands on 

the basis of multiple use in a manner that will protect the quality of historical resources and 

archaeological values. No distinction is made regarding National Register eligibility. FLPMA is the 

primary basis for managing cultural resources on the public lands. 

American Indian Religious Freedom Act of 1978 – establishes the policy of the United States to 

protect and preserve for the American Indian, Eskimo, Aleut, and Native Hawaiian the inherent 

right of freedom to believe, express, and exercise their traditional religions. Federal agencies are 

directed to evaluate their policies and procedures to determine if changes are needed to ensure 

that such rights and freedoms are not disrupted by agency practices. 

Archaeological Resources Protection Act of 1979 – provides felony-level penalties for the 

unauthorized excavation, removal, damage, alteration, defacement, or the attempted 

unauthorized removal, damage, alteration, or defacement of any archaeological resource, more 

than 100 years of age, found on public lands or Indian lands. The act also prohibits the sale, 

Seminoe Road Gas Development Project M-5 
Draft Environmental Impact Statement November 2005

purchase, exchange, transportation, receipt, or offering of any archaeological resource obtained 

from public lands or Indian lands. 

Executive Order 13007: Indian Sacred Sites – establishes access to and ceremonial use of Indian 

sacred sites by Indian religious practitioners on federal lands. The federal agencies shall avoid 

adversely affecting the physical integrity of such sacred sites and maintains confidentiality of said 

sites. 

Executive Order 13084: Consultation and Coordination with Indian Tribal Governments – 

establishes all federal agencies are required to consult with Native American tribes when 

developing regulatory policies that may affect tribal communities. 

Programmatic Agreement Among the Bureau of Land Management, The Advisory Council on 

Historic Preservation and the National Conference of SHPOs Regarding the Manner in Which 

BLM will meet its Responsibilities under the National Historic Preservation Act. 

State Protocol Agreement between the Wyoming BLM State Director and Wyoming SHPO. 

M-6 Seminoe Road Gas Development Project 
Appendix N 

Soils and Vegetation Information 
November 2005 Draft Environmental Impact Statement

Appendix N – Soils and Vegetation Information

PLANT SPECIES LIST


Common Name2 Code Scientific Name1 

Region 9 

Wetland 

Status3 

Weed/Sensitive 

Plant Status4, 5, 6 

Graminoids 

Alkali bluegrass POJU Poa juncifolia var. ampla FACU+ 

Alkali bluegrass POJU Poa juncifolia var. juncifolia FACU+ 

Alkali cordgrass SPGR Spartina gracilis FACW 

Alkali sacoton SPAI Sporobolus airoides FAC* 

Annual rabbitfoot grass POMO Polypogon monspeliensis FACW 

Baltic rush JUBA Juncus balticus FACW+ 

Basin wildrye ELCI Elymus cinereus (Leymus 

cinereus) FAC 

Blackroot sedge CAEL Carex elynoides 

Bluebunch wheatgrass ELSP Elymus spicatus UPL 

Bluegrass POA Poa sp. 

Bottlebrush squirreltail ELEL Elymus elymoides 

(Sitanion hystrix) FACUBulrush Scirpus Scirpus sp. OBL 

Burreed Sparganium Sparaganium sp. OBL 

Canada bluegrass POCO Poa compressa FACU+ 

Cattail Typha Typha OBL 

Cheatgrass VRITE/ANTE Bromus tectorum 

(Anisantha tectorum) - BLM Weedy Species 

of Concern 

Clustered field sedge CAPR Carex praegracilis) FACW 

Contracted Indian 

ricegrass ORCO/ACCO Oryzopis contracta 

(Achnatherum contractum) -

Creeping bentgrass AGST Agrostis stolonifera FAC* 

Creeping spikerush ELPA Eleocharis palustris OBL 

Crested wheatgrass AGCR Agropyron cristatum var. 

desortum _ 

Cusick alkaligrass PUCU Puccinellia cusickii NI 

Douglas sedge CADO Carex douglasii FACFlattened rush; 

Roundfruit rush JUCO Juncus compressus OBL 

Foxtail barley 

HOJU; CRJU 

HOCA 

Hordeum jubatum 

(Critesion jubatum) 

Hordeum x caespitosum 

FAC 

Green needlegrass STVI/NAVI Stipa viridula 

(Nasella virdula) -

Hardstem bulrush SCAC 

Schoenplectus acutus var. 

occidentalis 

(Scirpus acutus) 

OBL 

Indian ricegrass ORHY/ACHY Oryzopsis hymenoides 

(Achnatherum hymenoides) UPL 

Inland slatgrass DIST Distichlis stricta 

Distichlis stricta ssp spicata FAC+ 

Kentucky bluegrass POPR Poa pratensis FAC 

Marsh arrowgrass TRPA Triglochin palustris OBL 

Mat muhly MURI Muhlenbergia richardsonis FAC+ 

Meadow barley HOBR Hordeum brachyantherum FACWMeadow foxtail ALPR Alopecurus pratensis FACW 

Seminoe Road Gas Development Project N-1 
November 2005 Draft Environmental Impact Statement

Common Name2 Code Scientific Name1 

Region 9 

Wetland 

Status3 

Weed/Sensitive 

Plant Status4, 5, 6 

Narrow-leaved sedge; 

Neddleleaf sedge CAST Carex stenophylla -

Nebraska sedge CANE Carex nebrascensis OBL 

Needle-and thread STCO/HECO Stipa comata 

(Heterostipa comata) 

Nuttall’s alkaligrass PUNU Puccinellia nuttalliana FACW+ 

Prairie junegrass KOMA Koeleria macrantha -

Pulp muhly MUFI Muhlenbergia filiformis FACWSaltmarsh bulrush BOMA/SCMA 

Bolboschoernus maritimus var 

paludosus 

(Scirpus maritimus) 

OBL 

Sandberg bluegrass POSE 

Poa secunda var. secunda 

(Poa sandbergii) 

(Poa canbyi) 

-

Seaside arrowgrass TRMA Triglochin maritime var. elata OBL 

Sedge CAREX Carex sp. -

Shortawn foxtail ALAE Alopecurus aequalis OBL 

Slender wheatgrass ELTR Elymus trachycaulus 

(Agropyron trachycaulum) FAC 

Thickspike wheatgrass ELLA 

Elymus lanceolatus 

(Agropyron dasystachyum) 

Agropyron lanceolatum) 

FACUThreadleaf sedge CAFI Carex filifolia -

Threesquare bulrush SCPU Schoenoplectus pungens 

Scirpus pungens) OBL 

Toad rush JUBU Juncus bufonius FACW 

Weeping alkaligrass PUDI Puccinellia distans FACW+ 

Western wheatgrass ELSM 

Elymus smithii 

(Agropyron smithii) 

(Pascopyron smithii) 

FACU 

Woolly sedge CALA/CAPE Carex lanuginose 

(Carex pellita) OBL 

Shrubs/Subshrubs/Trees 

Basin big sagebrush ARTRTR Artemisia tridentate var. 

tridentate -

Birdfoot sagebrush; 

Birdsfoot sagebrush ARPE Artemisia pedatifida -

Black sagebrush ARNO Artemisia nova -

Broom snakeweed GUSA Gutierrezia sarothrae -

Fourwing saltbush ATCA Atriplex canescens UPL 

Fringed sagebrush; 

Fringed sagewort ARFR Artemisia frigida -

Gardner’s saltbush ATGA Atriplex gardneri var. gardneri -

Gardner’s saltbush ATGA Atriplex gardneri var. utahensis -

Greasewood SAVE Sarcobatus vermiculatus FACU+ 

Green rabbitbrush; 

Douglas rabbitbrush CHVI Chrysothamnus viscidiflorus -

Mountain mahogany CEMO Cercocarpus montanus 

Mountain snowberry; 

Utah snowberry 

SYOR Symphoricarpos oreophilus var. 

utahensis UPL 

Rocky Mountain juniper JUSC Juniperus scopulorum 

Rose Rosa Rosa sp. -

Rubber rabbitbrush CHNA/ERNA Chrysothamnus nauseosus 

(Ericamerica nauseosa) -

Sandbar willow SAEX Salix exigua OBL 

N-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Common Name2 Code Scientific Name1 

Region 9 

Wetland 

Status3 

Weed/Sensitive 

Plant Status4, 5, 6 

Shadscale saltbush; 

Spiny saltbush; 

Shadscale 

ATCO Atriplex confertifolia -

Shortspine horsebrush; 

Catclaw horsebrush TESP Tetradymia spinosa -

Silver sagebrush ARCA Artemisia cana FACU* 

Skunkbush sumac RHARTR Rhus aromatica var trilobata 

(Rhus trilobata) NI 

Spineless horsebrush TECA Tetradymia canescens -

Spiny hopsage GRSP Grayia spinosa -

Tamarisk, Chinese 

saltcedar; Fivestamen 

tamarisk; saltcedar 

TACH Tamarix chinensis FACW WY Noxious Weed 

Wax currant; 

Squaw currant RICE Ribes cereum FAC 

Winterfat KRLA Krascheninnikovia lanata -

Woods’ rose RWO Rosa woodsii 

Wyoming big sagebrush ARTRWY Artemisia tridentate var. 

wyomingensis -

Forbs 

Alkali buttercup; 

Seaside buttercup 

RACY Ranunculus cymbalaria OBL 

Alkali rayless aster ASBR/SYCI Aster brachyactis 

(Symphyotrichum ciliolatum) FACW 

Alyssum ALPA Alyssum parviflorum -

American vetch VIAM Vicia Americana 

Arrowleaf balsamroot BASA Balsamorhiza sagittata -

Arum leaf arrowhead; 

Northern arrowhead SACU Sagittaria cuneata OBL 

Biennial wormwood ARBI Artemisia biennis FACW 

Blue mustard; 

Crossflower CHTE Chorispora tenella -

Brook cinquefoil PORI Potentilla rivalis FACW 

Buckwheat Eriogonum Eriogonum sp. -

Bull thistle CIVU Cirsium vulgare FACU 

Burreed Saparganium Sparganium 

Bushy bird’s beak CORA Cordylanthus ramosus 

Canadian thistle; 

Canada thistle CIAR Cirsium arvense FACU+ WY Noxious Weed 

Catseye; 

Cryptantha Cryptantha Cryptantha sp. -

Cattail Typha Typha sp. OBL 

Chile aster; 

Aster ASAS/SYAS Aster ascendens 

(Symphyotrichum ascendens)s -

Clasping pepperweed LEPE Lepidium perfoliatum FACU+ 

Common dandelion TAOF Taraxacum officinale FACU 

Curlycup gumweed GRSQ Grindelia squarrosa FACU BLM Weedy Species 

of Concern 

Cushion buckwheat EROV Eriogonum ovalifolium far 

purpureum -

Cutleaf nightshade SOTR Solanum triflorum -

Dandelion Taraxacum Taraxacum sp. 

Desert biscuitroot’ 

Hairy seed lomatium LOFO Lomatium foeniculaceum -

Desert madwort; 

Alyssum ALDE Alyssum desertorum -

European stickseed LASQ Lappula squarrosa -

Seminoe Road Gas Development Project N-3 
November 2005 Draft Environmental Impact Statement

Common Name2 Code Scientific Name1 

Region 9 

Wetland 

Status3 

Weed/Sensitive 

Plant Status4, 5, 6 

Field pennycress THAR Thlaspi arvense NI 

Fivehorn smotherweed BAHY Bassia hyssopifolia FACW BLM Weedy Species 

Flatspine burr ragweed; 

Annual bursage AMAC Ambrosia acanthicarpa 

Flixweed; 

Herb Sophia DESO Desurainia Sophia - BLM Weedy Species 

Flodman’s thistle CIFL Cirsium flodmanii NI 

Fremont’s goosefoot CHFR Chenopodium fremontii 

Geyer’s larkspur DEGE Delphinium geyeri Carbon County 

Declared Weed 

Golden dock RUMA Rumex maritimus FACW+ 

Goldenrod Solidago Solidago sp. 

Goosefoot Chenopodium Chenopodium sp. 

Granite prickly gilia; 

Prickly phlox 

LEPU 

LIPU 

Leptodactylon pungens 

(Linanthus pungens) -

Great Plains stickseed LACE Lappula cenchrusoides -

Hairy whitetop CAPU Cardaria pubescens - WY Noxious Weed 

Halogen HAGL Halogeton glomeratus -

BLM Weedy Species 

of Concern; 

Carbon County 

Declared Weed 

Hoary false madwort BEIN Berteroa incana -

Hoary tansy aster MACA Machaeranthera canescens -

Hooker’s sandwort ARHO/ERHO Arenaria hookeri 

(Eremogone hookeri) -

Indian paintbrush Castilleja Castilleja sp. 

Kochia; 

Mexican summercypress BASI/KOSC Bassia sieversiana 

(Kochia scoparia) FAC 

Large flower 

skeletonplant 

Prairie pink 

LYGR Lygodesmia grandiflora -

Leafy rayless aster ASFR/SYFR Aster frondosus 

(Symphyotrichum frondosum) FACW+ 

Lesser burdock ARMI Arctium minus - WY Noxious Weed 

Littleleaf pussytoes ANMI Antennaria microphylla -

Louisiana -agewort; 

White sagebrush ARLU Artemisis ludoviciana UPL 

Low pussytoes ANDI Antennaria dimorpha -

Lupine Lupinus Lupinus sp. -

Mariposa lily Calochortus Calochortus sp. 

Mat amaranth; 

Prostrate pigweed AMBL Amaranthus blitoides FACW 

Milkvetch Astragalus Astragalus sp. 

Narrowleaf milkvetch ASPE Astragalus pectinatus 

Nodding buckwheat ERCE Eriogonum cemuum -

Northern water plantain ALTR 

Alisma triviale 

(Alisma plantago aquatica ssp. 

Brevipes) 

OBL 

Norwegian cinquefoil PONO Potentilla norvegica FAC 

Nuttail’s larkspur DENU Delphinium nuttallianum 

Nuttail’s povertyweed MONU Monolepis nuttaliana FACOakleaf goosefoot CHGL Chenopodium glaucum var. 

salinum FAC 

N-4 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Common Name2 Code Scientific Name1 

Region 9 

Wetland 

Status3 

Weed/Sensitive 

Plant Status4, 5, 6 

Paradox cinquefoil; 

Bushy cinquefoil POPA Potentilla paradoxa FACW 

Persistent sepal yellowcress ROCA Rorippa calycina FACW BLM Species of 

Concern 

Pinyon goosefoot CHAT Chenopodium atrovirens -

Pitseed goosefoot; 

Zschack’s goosefoot CHBE Chenopodium berlandieri -

Plains pricly pear OPPO Opuntia polyacantha - Carbon County 

Declared Weed 

Povertyweed; 

Smallflower sumpweed IVAX Iva axilaris FAC 

Prairie goldenbanner; 

Round-leaf false-lupine THRH Thermopsis rhombifolia FACU 

Prairie thistle CICA Cirsium canescens -

Prickly lettuce LASE Lactuca serriola FACU 

Princesplume Stanleya Stanleya sp. 

Prostrate knotweed POAV Polygonum aviculare FACWProstrae vervain; 

Big bract verbena VEBR Verbena bracteata FAC* 

Pursh seepweed SUCA Suaeda calceoliformis -

Red goosefoot CHRU Chenopodium rubrum var. 

rubrum FACW+ 

Red swampfire; 

Red saltwort SARU Salicomisrubra OBL 

Redwool plantain; 

Saline plantain PLER Plantago eriopoda FACW 

Rocky Mountain bee 

plant CLSE Cleome serrulata FACU 

Rosy pussytoes ANRO Antennaria rosea -

Rough cocklebur XAST Xanthium strumarium FAC 

Rush skeletonplant; 

Skeletonweed LYJU Lygodesmia juncea -

Russian knapweed CERE Centaurea repens WY Noxious Weed 

Russian thistle; Prickly 

Russian thistle SATR/SAKA Salsola tragus 

(Salsola kali) -/UPL BLM Weedy Species 

of Concern 

Saline saltbush; 

Spearscale ATSU Atriplex subspicata -

Salsify; 

Goatsbeard Tragopogon Tragopogon sp. -

Scarlet globemallow SPCO Sphaeralcea coccinea 

Scotch thistle ONAC Onopordum acanthium - WY Noxious Weed 

Sea-milkwort GLMA Glaux maritime FACW+ 

Silverscale saltbush ATAR Atriplex argentea FACSilverweed cinquefoil POAN Potentilla anserine 

(Argentina anserine) OBL 

Silvery lupine LUAR Lupinus argenteus -

Skeleton burr ragweed; 

Perennial bursage AMTO Ambrosia tomentosa -

Small flower sandpuff; 

Small flower sand 

verbena 

TRMI Tripterocalyx micranthus ?? 

Smooth woodyaster XYGL Xylorhiza glabriuscula var. 

glabriscula 

Spiny phlox; 

Hoods’s phlox PHHO Phlox hoodii -

Stemles goldenweed HAAC Haplopappus acaulis 

Tansymustard Descurainia Descurainia sp. -

Seminoe Road Gas Development Project N-5 
November 2005 Draft Environmental Impact Statement

Common Name2 Code Scientific Name1 

Region 9 

Wetland 

Status3 

Weed/Sensitive 

Plant Status4, 5, 6 

Thistle Cirsium Cirsium sp. 

Tumbling orache; 

Tumbling saltweed ATRO Atriplex rosea FACU 

Two-grooved milkvetch ASBI Astragalus bisulcatus -

Two-seed orache; 

Twoscale saltbush ATHE Atriplex heterosperma -

Water smartweed POAM Polygonum amphibium OBL 

Waterthread pondweed PODI Potamogeton diversifolius OBL 

Western marsh 

cudweed GNPA Gnaphalium palustre FAC+ 

Western tansymustard DEPI Descurainia pinnata 

Western yarrow ACMI Achillea millefolium var. 

lanulosa FACU 

White water crowfoot; 

White water buttercup 

RAAQ Ranunculus aquatilis OBL 

White wild onion; 

Textile onion ALTE Allium textile 

Whitetop; 

Hoary cress; 

Pepperweed whitetop 

CADR Cardaria draba - WY Noxious Weed 

Wild mint; 

Wild field mint MEAR Mentha arvensis FACWWillowleaf dock; 

Willow dock RUSA Rumex salicifolius var. 

triangulivalvis FACW 

Wyoming thistle CIPA Cirsium pulchemimum 

Yellow salsify TRDU Tragopogon dubius 

Yellow spider-flower; 

Yellow bee plant CLLU Cleome lutea FACU 

Yellow sweetclover MEOF Melilotus officinalis FACU 

Miscellaneous 

Field Horsetail EQAR Equisetum arvense FAC 

Lichen PACH/XACH Pamelia chlorochroa 

(Xanthopamelia chlorochroa) 

Soil biomass/algae Oscillatoria, Lyngbya, 

Phormidium 

Notes: 

1. Taxonomy based on Vascular Plants of Wyoming 3rd Edition (Dorn 2001). 

2. Common names based on Vascular Plants of Wyoming 3rd Edition (Dorn, 200); Checklist of the Vascular 

Plants of Wyoming (Nelson & Hartman 1994). 

3. Wetland status based on National List of Plant Species that Occur in Wetlands: Northwest (Region 9) 

(Resource Management Group Inc., 1993) and 1993 Supplement to List of Plant Species that Occur in 

Wetlands Northwest (Region 9); Supplement to Biological Report 88 (Reed, P. 1993) 

4. Weed/Sensitive Plant status per BLM Rawlins Field Office, Wyoming Weed and Pest Control Act of 1973, 

and Wyoming Natural Diversity Database (WYNDD). 

5. BLM Weedy Species of Concern (Foley, 2003). 

6. Adapted from 2003 Declared List of Weed and Pests for Carbon County (Wyoming Weed and Pest Council). 

N-6 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement

Soil Baseline Characteristics and Interpretations of Dominant Soil Map Units 


Northern Project Boundary to Seminoe Reservoir/North Platte River 

Map Unit

1 202 334 336 436 438 

Topographic 

Position Ridges Terraces, Alluvial Fans 

Rolling/Sloping 

Uplands Uplands Sloping Residual Uplands 

Slope % 6 to 30 0 to 8 8 to 30 0 – 6 2 to 10 

Depth Very Shallow – 

Shallow Deep Very Shallow – Shallow 

Moderately Deep 

– Deep 

Shallow – 

Moderately Deep 

pH 8.0 – 8.4 8.2 – 8.4 8.2 – 8.8 8.2 – 8.6 8.6 – 9.2 

Surficial Textures

2 chfsl - chci I (EC) I – cl (EC) fsl l – cl (EC) 

Runoff Potential High Slow High Slow - Moderate Moderate - High 

Water Erosion 

Hazard Severe Slight/Severe Severe Slight/Moderate Slight/Severe 

Wind Erosion 

Hazard Moderate Moderate Moderate Moderate 

Available Water 

Capacity 

Very Low Moderate Very Low - Low Low - Moderate Low 

Range Site 

(Names) 

Very Shallow 

Shale Saline Upland 

Shale, 

Saline Upland, 

Shallow Loamy 

Sandy Saline Upland 

Map Unit

1 452 446 456 483 837 

Topographic 

Position 

Rolling/Sloping 

Uplands Uplands Alluvial Fans, 

Bottomlands 

Alluvial Fans, 

Terraces, 

Bottomlands 

Upland Sideslopes, 

Toe Slopes, 

Alluvial Fans 

Slope % 3 to 8 1 to 4 0 to 3 0 to 3 3 to 15 

Depth 

Shallow – 

Moderately 

Deep 

Very Shallow – 

Shallow Deep Deep Moderately Deep – 

Deep 

pH 8.2 – 8.8 8.2 – 8.8 8.0 – 9.4 8.0 – 9.4 7.2 – 8.8 

Surficial Textures

2 fsl – sl chl – l lls – scl (EC) sl – scl (EC) fsl – scl 

Runoff Potential Moderate – 

High Slow – Medium Low – High High Medium 

Water Erosion 

Hazard Slight/Severe Moderate / 

Severe Slight Slight Slight/Moderate 

Wind Erosion 

Hazard Moderate Moderate / 

Severe Moderate Moderate 

Available Water 

Capacity 

Low Very Low Low – High High Moderate – High 

Range Site 

(Names) Shallow Sandy Shale Saline Upland Saline Upland Loamy 

Map Unit

1 1402 1475 

Topographic 

Position 

Undulating Hills 

With Low 

Ridges and 

Knolls 

Alluvial Fans, 

Terraces 

Slope % 3 to 20 3 to 15 

Depth Shallow – Deep Deep 

pH 8.0 – 8.8 8.0 – 9.0 

Surficial Textures

2 sl sl – scl 

Runoff Potential Moderate ­

High Moderate 

Water Erosion 

Hazard Slight/Severe Slight/Severe 

Wind Erosion 

Hazard Moderate Moderate 

Available Water 

Capacity 

Moderate – 

Very Low 

Moderate – 

High 

Seminoe Road Gas Development Project N-7 
Appendix O 

Erosion Management for 

Ephemeral Drainages 
November 2005 Draft Environmental Impact Statement 

Appendix O – Erosion Management for 

Ephemeral Drainages 

Ten ephemeral drainages are being considered as potential discharge drainages for produced 

water associated with the proposed action (Alternative B) for the Seminoe Road Project. See 

Section 2.4, Alternative B – Proposed Action, in the main body of this EIS. This appendix 

presents information pertinent to the erosion management of these drainages. 

As discussed in Section 3.4.4, Ephemeral Drainages within the EIS Analysis Area, ephemeral 

drainages typically flow in response to precipitation in the contributing watershed or in response to 

runoff created by snowmelt. As flow concentrates in these drainages, the processes of 

aggradation and degradation occur. In ephemeral drainages, degradation of the channel generally 

results from channel incision or headcut formation as the erosive energy of the water dislodges 

and transports the soil material in the channel bed. Channel incision can also create instability in 

the channel banks and facilitate channel widening through bank erosion. 

Aggradation, or sediment deposition, also occurs within an ephemeral drainage as the capacity to 

transport sediment is reduced during the falling limb of the runoff hydrograph. This sediment 

remains in the channel until mobilized by future runoff events. Both processes naturally occur in 

ephemeral drainages with the Seminoe Road Project EIS analysis area as evidenced by the 

presence of headcuts, unstable channel banks, gully formation and sediment deposition within the 

drainage channels. 

This appendix is designed to provide a general overview of the type and extent of erosion 

management that could be implemented within the EIS analysis area to manage and minimize 

potential erosion and channel instability associated with a sustained flow of produced water that 

would be released into the drainages from the proposed action contemplated under Alternative B. 

An erosion process has been historically active within the existing ephemeral drainages of the 

existing drainages (see Section 3.4.4, Ephemeral Drainages within the EIS Analysis Area). It is 

anticipated that this erosion process would continue to occur but would be exacerbated by the 

discharge and flow of project produced water; consequently, the intent of an erosion management 

plan is to minimize or limit the erosion process. 

Seminoe Road Gas Development Project O-1 
Draft Environmental Impact Statement November 2005 

Erosion management would involve the placement of structures within the drainage channels to: 

(1) stabilize areas where headcuts presently exist; and (2) limit the downcutting or depth of 

headcuts that may be created by the addition of water into the drainages. Two general concepts 

have been identified and are described below: 

(a)	 Placement of rock grade control structures in the ephemeral drainages. These 

structures would be placed where the channels are not deeply incised and 

existing headcuts or downcutting do not exceed 3 feet. 

(b)	 Placement of rock check dams in the ephemeral drainages. These structures 

would be placed where the channels are deeply incised and the existing headcuts 

or downcutting exceed 3 feet. Typically, these structures would be placed above 

the confluence of the existing channels with full pool level of Seminoe Reservoir. 

Rock grade control structures would be placed below the invert of the existing drainage channels. 

The intent of the grade control structures (which include sheet piling and gabions) is to limit the 

channel degradation or downcutting, should erosion occur, to a maximum depth not exceeding 3 

feet. Limiting the channel headcut to a depth of 3 feet reflects the historic erosional patterns within 

the drainages, limits the erosion associated with unstable banks, and provides for access by 

wildlife and livestock. The location of the structures is based on the assumptions listed below. 

(a)	 Place a structure immediately upstream of all existing headcuts in the existing 

drainage channels; 

(b)	 Place structures along each drainage to limit the downcutting to a maximum 

depth not exceeding 3 feet. The distance between structures is based on the 

difference between the existing channel slope and the anticipated slope 

associated with the upstream migration of the channel headcut. Based on the 

review of preliminary information available for the ten ephemeral drainage 

channels, this slope is assumed to be 0.5% (0.005 ft/ft). 

(c)	 The project water would concentrate within the drainage channels and create a 

channel/headcut that would migrate upstream. The channel incised into the native 

materials is assumed to be not more than 3 feet in depth, and not more than 2 

O-2 Seminoe Road Gas Development Project 
November 2005 Draft Environmental Impact Statement 

feet in width. A channel with this configuration and a slope of 0.5% would convey 

a maximum discharge (flow) of 26 cubic feet per second (cfs). 

Rock check dams utilized in conjunction with the rock grade control structures would minimize the 

potential for erosion and would also provide a location for sediment deposition upstream of each 

check dam. Installation of rock check dams involves the placement of rock above the invert of the 

existing drainage channels. Plunge pools below each structure would also be stabilized with rock. 

At least one rock check dam would be placed at the downstream reach or outfall of each drainage 

channel above the confluence of the channel with the North Platte River or the full pool level of 

Seminoe Reservoir. 

Table O-1, Estimates of Erosion Management Structures (Alternative B), presents preliminary 

information related to erosion management in the intermittent and ephemeral drainages of the EIS 

analysis area. Figure 13, Conceptual Details for Erosion Management Structures, provides 

conceptual details for both the rock grade control structures and the rock check dam structures. 

Seminoe Road Gas Development Project O-3 
Draft Environmental Impact Statement November 2005 

Table O-1, Estimates of Erosion Management Structures (Alternative B) 

Drainage 

Name1 

Channel 

Length 

(fee)

2 

Average 

Gradient 

(%)

3 

Number of 

Rock Grade 

Control 

Structures4 

Number of 

Rock Check 

Dam 

Structures5 

Length of 

New Roads 

(feet)

6 

Estimated 

Disturbed 

Area 

(acres)7 

Pool Table Draw 30,000 1.2 60 1 30,000 18 

Ayers Draw 1,000 1.3 3 1 1,000 1 

Dry Ditch 6,700 1.0 11 1 6,700 4 

Dirtyman Draw 21,500 1.7 8 1 21,500 14 

Longhart Draw 2,500 2.3 13 1 2,500 2 

Unnamed 

Drainage #1 1,000 2.8 7 1 1,000 1 

Unnamed 

Drainage #2 1,400 15 5 1 1,400 1 

Mountain Lion 

Draw 4,300 1.7 17 1 4,300 3 

St. Mary’s Ditch 3,000 1.3 8 1 3,000 2 

Unnamed 

Drainage #3 1,000 4.4 10 1 1,000 1 

O’Brien Creek8 16,000 1.8 64 1 16,000 10 

Total 88,400 - 284 11 88,400 57 

Notes: 

1. Refer to Figure 12, Produced Water Discharge Points – Alternative B. 

2. This is the estimated length of the drainage channel receiving produced water under Alternative B. 

3. Average gradients for ephemeral drainages from Table 3.4-4, Ephemeral Drainage Watershed 

Characteristics. Average gradient for O’Brien Creek from Table 3.4-2 Intermittent Drainage Watershed 

Characteristics. 

4. Number of rock grade control structures is based on a maximum headcut depth of 3 feet and a slope of the 

headcut channel of 0.005 ft/ft. 

5. Number of rock check dam structures assumes a minimum of one structure per drainage to trap sediment 

and dissipate erosive energy. Where channel incision is increased, the number of structures is determined by 

the slope of the existing channel and a maximum height of 5 feet for each structure. 

6. New roads would need to be constructed to access engineered structures in each drainage. It is assumed 

that the access roads will be located adjacent to the drainages. These roads are assumed to be two-track, 

non all weather roads. 

7. Estimated disturbed areas are determined using the following assumptions: 

Rock Grade Control Structures: 10 feet across (perpendicular to the flow in the drainage) and 50 feet 

wide. (Assume 0.01 acre per structure.) 

Rock Check Dam Structure: 60 feet across (perpendicular to the flow) including the rock apron, 50 feet 

wide. (Assume 0.07 acre per structure.) 

New Road: 25 feet wide for two-track road construction 

8. O’Brien Creek is an intermittent drainage, which is a stream that is below the local water table for at least part 

of the year. 

O-4 Seminoe Road Gas Development Project