Final EIS Appendix 19 

APPENDIX 19—AIR QUALITY TECHNICAL SUPPORT 

DOCUMENT 

This Air Quality Technical Support Document (AQTSD) describes the processes used to conduct the air 

quality impact assessment and provides summaries of relevant analysis data. This document served as the 

basis for air quality impact analyses of all alternatives. The contents of this document are— 

• Regulatory Framework 

• Agency Roles and Authorities 

• Existing Air Quality 

• Air Quality Impact Analysis 

• Emission Calculations 

• Internet Resources 

• Mitigation. 

Copies of this technical support document and any data files are available upon request from— 

John Zachariassen 

Physical Scientist: Air Quality 

5353 Yellowstone 

PO Box 1828 

Cheyenne, Wyoming 82003 

307-775-6235 Voice 

307-775-6042 Fax 

john_zachariassen@blm.gov 

Regulatory Framework 

For quantitative analysis, the following air quality criteria apply. Although the criteria listed below do not 

apply to the qualitative analysis presented in this final environmental impact statement (EIS), they are 

identified here for reference purposes. The basic framework for controlling air pollutants in the United 

States is mandated by the 1970 Clean Air Act (CAA) and its amendments, and the 1999 Regional Haze 

Regulations. The CAA addresses criteria air pollutants, state and national ambient air quality standards 

for criteria air pollutants, and the Prevention of Significant Deterioration program. The Regional Haze 

Regulations address visibility impairment. 

Ambient Air Quality Constituents 

Air pollutants addressed in this study include criteria pollutants, hazardous air pollutants (HAP), and 

sulfur and nitrogen compounds that can cause visibility impairment or atmospheric deposition impacts. 

Criteria Pollutants 

Criteria pollutants are those for which national standards of concentration have been established. Ambient 

air concentrations of these constituents greater than the standards represent a risk to human health. 

Criteria pollutants include carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone 

(O3), particulate matter (PM10 and PM2.5), and lead (Pb). 

Pinedale RMP A19-1 
Appendix 19 Final EIS 

• Carbon Monoxide. CO is an odorless, colorless gas formed during any combustion process, such 

as operation of engines, fireplaces, and furnaces. High concentrations of CO affect the oxygencarrying capacity of the blood and can lead to unconsciousness and asphyxiation. Wildland fires 

are a natural source of CO. 

• Nitrogen Dioxide. NO2 is a red-brown gas formed during operation of internal combustion 

engines. Such engines emit a mixture of nitrogen gases, collectively called nitrogen oxides (NOx). 

NOx can contribute to brown cloud conditions and can convert to ammonium nitrate particles and 

nitric acid, which can cause visibility impairment and acid rain. Bacterial action in soil can be a 

natural source of nitrogen compounds. 

• Sulfur Dioxide. SO2 forms during combustion from trace levels of sulfur in coal or diesel fuel. It 

can convert to ammonium sulfate ((NH4)2SO4) and sulfuric acid (H2SO4), which can cause 

visibility impairment and acid rain. Volcanoes are natural sources of SO2. Anthropogenic sources 

include refineries and power plants. 

• Ozone. O3 is a faint blue gas that is generally not emitted directly into the atmosphere but is 

formed from NOx and volatile reactive organic compound (VOC) emissions. Internal combustion 

engines are the main source of NOx. Volatile organic compounds, like terpenes, are very reactive. 

Sources of VOCs include, but are not limited to, paint, varnish, and some types of vegetation. The 

faint acrid smell common after thunderstorms is caused by ozone formation by lightning. O3 is a 

strong oxidizing chemical that can burn lungs and eyes, and damage plants. 

• Particulate Matter. Particulate matter (e.g., soil particles, hair, pollen) is essentially small 

particles suspended in the air that settle to the ground slowly and may be resuspended if 

disturbed. Separate allowable concentration levels for particulate matter are based on the relative 

size of the particle: 

– PM10 particles with diameters smaller than 10 micrometers are small enough to be inhaled 

and can cause adverse health effects. 

– PM2.5 particles with diameters smaller than 2.5 micrometers are so small that they can be 

drawn deeply into the lungs and cause serious health problems. Particles in this size range are 

also the main cause of visibility impairment. 

• Lead. Before the wide use of unleaded fuel for automobiles, lead particles were emitted from 

tailpipes. Lead is not considered in this final EIS because no proposed projects are expected to 

emit lead. The lead standard is not addressed in this Technical Support Document because 

proposed projects will have no lead emission sources. 

Hazardous Air Pollutants 

There are a wide variety of HAPs, including N-hexane, ethylbenzene, toluene, xylene, formaldehyde, and 

benzene. Although HAPs do not have ambient air quality standards associated with them, the 

Environmental Protection Agency (EPA) has issued reference concentrations (RfC) to evaluate the 

inhalation risk for cancerous and noncancerous health effects. 

Although this final EIS is a National Environmental Policy Act (NEPA) document and not a regulatory 

document, there are regulatory issues that should be taken into account in preparing this final EIS and 

ensuing project-specific EISs. Actual regulation of HAPs is achieved through compliance with applicable 

maximum achievable control technology (MACT) standards and not through ambient air quality 

standards. Regulatory agencies implement control through section 112 programs, specifically section 

112(g) case-by-case MACT determinations according to 40 Code of Federal Regulations (CFR) part 63, 

subpart B and section 112(d) MACT emission standards. 

A19-2 Pinedale RMP 
Final EIS Appendix 19 

Any source that emits or has the potential to emit 10 tons per year or more of any HAP or 25 tons per year 

or more of any combination of HAPs is considered a major source and would require a Title V, part 70, 

operating permit review and permit. This may include either compliance with an applicable MACT 

emission standard or a case-by-case 112(g) MACT determination if the source is new or is the result of 

major modifications and no applicable MACT emission standard has been promulgated. Specific 

regulations that would apply in the planning area in 2004 include 40 CFR part 63 subpart HH National 

Emission Standards for Hazardous Air Pollutants From Oil and Natural Gas Production Facilities; 40 

CFR part 63 subpart HHH, National Emission Standards for Hazardous Air Pollutants from Natural Gas 

Transmission and Storage Facilities; and 40 CFR Part 63 Subpart ZZZZ, National Emission Standards for 

Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines. This last regulation 

affects source categories using reciprocating engines for gas compression. 

For quantifiable analysis, short-term (1-hour) HAP concentrations would be compared with acute 

Reference Exposure Levels (REL). RELs are defined as concentrations at or below which no adverse 

health effects are expected. If no RELs were available, the available Immediately Dangerous to Life or 

Health (IDLH/10) values would be used. These IDLH/10 values are determined by the National Institute 

for Occupational Safety and Health (NIOSH) and would be obtained from EPA's Air Toxics Database. 

Also for quantifiable analysis, long-term exposure to HAPs emitted by the proposed action would be 

compared with RfCs. An RfC is defined by EPA as the daily inhalation concentration at which no longterm adverse health effects are expected. RfCs exist for both noncarcinogenic and carcinogenic effects on 

human health. Annual modeled HAP concentrations for all HAPs emitted would be compared directly 

with the noncarcinogenic RfCs. RfCs for the suspected carcinogens benzene and formaldehyde are 

expressed as risk factors. Accepted methods for risk assessment would be used to evaluate the 

incremental cancer risk for these pollutants. 

Annual modeled concentrations would be multiplied by EPA's unit risk factors (URF) (based on 70-year 

exposure) for those pollutants, and then the product would be multiplied by an adjustment factor that 

represents the ratio of projected exposure time to 70 years. The adjustment factors represent two 

scenarios: a most likely exposure (MLE) scenario and one reflective of the maximally exposed individual 

(MEI). 

The MLE duration would be assumed to be 9 years, which corresponds to the mean duration that a family 

remains at a residence. This duration corresponds to an adjustment factor of 9/70 = 0.13. The duration of 

exposure for the MEI is assumed to be 50 years (maximum duration at a location), corresponding to an 

adjustment factor of 50/70 = 0.71. 

A second adjustment would be made for time spent at home versus time spent elsewhere. For the MLE 

scenario, the at-home time fraction is 0.64 (EPA 1993), and it would be assumed that during the rest of 

the day, the individual would remain in an area where annual HAP concentrations would be one-quarter 

as large as the maximum annual average concentration. Therefore, the MLE adjustment factor would be 

(0.13) x [(0.64 x 1.0) + (0.36 x 0.25)] = 0.0949. The MEI scenario assumes that the individual is at home 

100% of the time, for a final adjustment factor of (0.71 x 1.0) = 0.71. 

HAP emissions are associated with industrial activities, such as oil and gas operations, refineries, paint 

shops, dry cleaning facilities, and woodworking shops. 

Because this analysis is qualitative, no specific impact analyses of either short- or long-term HAPs 

impacts are conducted. 

Pinedale RMP A19-3 
Appendix 19 Final EIS 

HAPs emissions are expected to be similar to those found in other EISs and to be composed of benzene, 

toluene, ethylbenzene, xylene, n-hexane, and formaldehyde. 

Atmospheric Deposition Constituents 

Sulfur and nitrogen compounds that can be deposited on terrestrial and aquatic ecosystems include nitric 

acid (HNO3), nitrate (NO3

-

), NH4

+

, and SO4

--. HNO3 and NO3-

 are not emitted directly into the air but 

form in the atmosphere from industrial and automotive emissions NOx. SO4

-- is formed in the atmosphere 

from industrial emission of SO2. Deposition of HNO3, NO3

-

, and SO4

-- can adversely affect plant growth, 

soil chemistry, lichens, aquatic environments, and petroglyphs. NH4

+

 is primarily associated with feedlots 

and agricultural fertilization. Deposition of NH4

+

 can affect terrestrial and aquatic vegetation. While 

deposition may be beneficial as a fertilizer, it can adversely affect the timing of plant growth and 

dormancy. 

Total nitrogen and sulfur deposition is calculated from dry deposition CASTNet data and wet deposition 

National Atmospheric Deposition Program (NADP) data. Total deposition data are then compared to 

levels of concern (LOC) thresholds developed by the Forest Service (Fox, et al 1989). 

Although this analysis is qualitative, future specific projects will require quantitative analyses using the 

following criteria. 

Wyoming and National Ambient Air Quality Standards 

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

(NAAQS) are health-based standards for the maximum concentration of air pollutants at all locations to 

which the public has access. The WAAQS and NAAQS are legally enforceable standards. Concentrations 

above the WAAQS and NAAQS represent a risk to human health. State standards must be equally strict 

or stricter than federal standards. 

The EPA has developed standards for each criteria pollutant for a specific averaging time (Table A19-1). 

Short averaging times (1, 3, and 24 hours) address short-term exposure, while the annual standards 

address long-term exposure. Longer term standards are set to lower allowable concentrations than are 

short-term standards to recognize the cumulative effects of long-term exposure. 

Table A19-1. National and Wyoming Ambient Air Quality Standards 

NAAQS WAAQS Pollutant Averaging 

Time (μg/m3) (ppm) (ppb) (μg/m3) (ppm) (ppb) 

Carbon 1-hour 40,000 35 35,000 40,000 35 35,000 

Monoxide 

(CO) 8-hour 10,000 9 9,000 10,000 9 9,000 

Lead 

(Pb) 

Calendar 

quarter 1.5 1.5 

Nitrogen 

Dioxide 

(NO2) 

Annual 100 .053 53 100 .053 53 

Ozone 

(O3) 8-hour 157 .075 75 157 .075 75 

Particulate 24-hour 150 150 

Matter 

(PM10) Annual revoked revoked 

A19-4 Pinedale RMP 
Final EIS Appendix 19 

Pinedale RMP A19-5 

NAAQS WAAQS Pollutant Averaging 

Time (μg/m3) (ppm) (ppb) (μg/m3) (ppm) (ppb) 

Particulate 24-hour 35 35 

Matter 

(PM2.5) Annual 15 15 

3-hour 1,300 .5 500 695 .266 266 

24-hour 365 .14 140 260 .099 99 

Sulfur 

Dioxide 

(SO2) Annual 80 .030 30 60 .023 23 

On September 21, 2006, EPA announced final revisions to the NAAQS for particulate matter. The 

revision strengthens the 24-hour PM2.5 standard from 65 to 35 micrograms per cubic meter (μg/m3

) and 

revokes the annual PM10 standard of 50 ug/m3

. EPA retained the existing annual PM2.5 standard of 15 

ug/m3

 and the 24-hour PM10 standard of 150 ug/m3. The ozone 8-hour NAAQS and WAAQS was 84 parts 

per billion (ppb) until March 12, 2008; on that date, the 8-hour NAAQS for ozone was revised to 75 ppb. 

After the final rule becomes effective, the State of Wyoming will enter into rulemaking to revise the 

WAAQS. 

Prevention of Significant Deterioration 

The goal of the Prevention of Significant Deterioration (PSD) program is to ensure that air quality in 

areas with clean air does not significantly deteriorate while maintaining a margin for future industrial 

growth. Under the PSD program, each area in the United States is classified by the air quality in that 

region according to the following system: 

• PSD Class I Areas: Congressional mandated PSD Class I Areas with pristine air quality, such as 

wilderness areas, national parks, and some Native American reservations, are accorded the 

strictest protection. Only very small incremental increases in concentration are allowed in order to 

maintain the air quality in these areas.

• PSD Class II Areas: Essentially all areas that are not designated Class I are designated Class II. 

Moderate incremental increases in concentration are allowed, although the concentrations are not 

allowed to reach the concentrations set by Wyoming and federal standards (i.e., WAAQS and 

NAAQS). 

• PSD Class III Areas: No areas have yet been designated Class III. Concentrations would be 

allowed to increase up to the WAAQS and NAAQS. 

The incremental increases allowed for specific pollutants in Class I and Class II areas are provided in 

Table A19-2. 

Table A19-2. PSD Increments 

PSD Increment 

Pollutant Class I Class II Averaging 

Time 

(μg/m3) (ppm) (ppb) (μg/m3) (ppm) (ppb) 

Nitrogen 

Dioxide 

(NO2) 

Annual 2.5 .0013 1.3 25 .013 13 

Particulate 24-hour 8 30 
Appendix 19 Final EIS 

A19-6 Pinedale RMP 

PSD Increment 

Pollutant Class I Class II Averaging 

Time 

(μg/m3) (ppm) (ppb) (μg/m3) (ppm) (ppb) 

Matter 

(PM10) Annual 4 17 

3-hour 25 .0096 9.6 512 .1956 196 

24-hour 5 .0019 1.9 91 .0348 35 

Sulfur 

Dioxide 

(SO2) Annual 2 .0008 .8 20 .0076 8 

Comparisons of potential PM10, NO2, and SO2 concentrations in NEPA air quality analyses with PSD 

concentrations are intended only to evaluate a threshold of concern and do not represent a regulatory PSD 

Increment Consumption analysis. Regulatory PSD Increment Consumption analyses are solely the 

responsibility of the State of Wyoming, which has been granted primacy (with EPA oversight). 

In project-specific EISs, the Bureau of Land Management (BLM) does not perform a regulatory PSD 

analysis. The PSD increments are used only as a reference to give the public a better understanding of the 

level of potential impact. 

Regional Haze Regulations 

Visibility impairment in the form of regional haze obscures the clarity, color, texture, and form of what 

one sees. Haze-causing pollutants (mostly fine particles) are directly emitted into the atmosphere or are 

formed when gases emitted into the air form particles as they are carried downwind. Emissions from 

human-caused and natural sources can be carried great distances, contributing to regional haze. The 

Wyoming Department of Environmental Quality–Air Quality Division (WDEQ-AQD) submitted its 

Regional Haze State Implementation Plan (SIP), in accordance with 40 CFR Part 51.309, in December 

2003. The EPA has not yet taken any action on this SIP. 

Visual range, one of several ways to express visibility, is the greatest distance at which a person can 

distinguish a dark landscape feature from a light background like the sky. Without human-caused 

visibility impairment, natural visual range is estimated to average about 110–115 miles in the western 

United States and 60–80 miles in the eastern United States (Malm 1999). Visibility can also be expressed 

in terms of deciview (dv), a measure for describing perceived changes in visibility. One dv is defined as a 

change in visibility that is just perceptible to an average person. 

The Regional Haze Regulations were developed by the EPA in response to the CAA Amendments of 

1977 and 1990. They are intended to maintain visibility on the least impaired days and improve visibility 

on the most impaired days in mandatory Federal Class I areas across the United States, so that visibility in 

these areas is returned to natural conditions by 2064. These regulations require states to submit a regional 

haze SIP and progress reports to demonstrate reasonable progress toward the 2064 goal. 

APPLICABILITY TO THE PINEDALE AREA

Air pollution impacts are limited by local, state, tribal, and federal air quality regulations, standards, and 

implementation plans established under the CAA and administered by the WDEQ-AQD with oversight 

from the EPA. Air quality regulations require proposed new, or modified existing, air pollutant emission 

stationary sources (including oil and gas compression facilities) to undergo a permitting review before 

their construction can begin. Therefore, the WDEQ-AQD has the primary authority and responsibility to 
Final EIS Appendix 19 

review permit applications and to require emission permits, fees, and control devices, before construction 

and/or operation. 

Fugitive dust and exhaust from construction activities (road and well pad construction; oil or gas well 

drilling and completion), along with air pollutants emitted during operation (e.g., well operations, booster 

[field] and pipeline [sales] compressor engines), are potential causes of air quality impacts. These issues 

are more likely to generate public concern where natural gas development activities occur near residential 

areas or near PSD Class I and sensitive Class II areas. 

The U.S. Forest Service (USFS), National Park Service (NPS), and the U.S. Fish and Wildlife Service 

(USFWS) have also expressed concerns regarding potential atmospheric deposition (i.e., acid rain) and 

visibility impacts within downwind PSD Class I and sensitive Class II areas under their administration 

throughout Wyoming. 

As explained earlier, the NAAQS and WAAQS are health-based standards for the maximum acceptable 

concentrations of air pollutants at locations to which the public has access. The analysis of the proposed 

alternatives must demonstrate continued compliance with all applicable local, state, tribal, and federal air 

quality standards. Existing air quality throughout the planning area (at the time of the preparation of this 

document and the collection of the data presented in Table A19-3) is in compliance with all ambient air 

quality standards, as demonstrated by the relatively low concentration levels presented in Table A19-3. 

The U.S. Congress (through the CAA section 116) authorized local, state, and tribal air quality regulatory 

agencies to establish air pollution control requirements more (but not less) stringent than federal 

requirements. Also, under both the Federal Land Policy and Management Act (FLPMA) and the CAA, 

BLM cannot authorize any activity that would not conform to all applicable local, state, tribal, and federal 

air quality laws, regulations, standards, and implementation plans. 

Given the planning area’s current air quality standards attainment status, future development projects that 

have the potential to emit more than 250 tons per year of any criteria pollutant (or certain listed sources 

that have the potential to emit more than 100 tons per year) would be required to undergo a site-specific 

regulatory PSD Increment Consumption analysis under the federal New Source Review permitting 

regulations. Development projects that require PSD permits may also be required by the applicable air 

quality regulatory agencies to incorporate additional emission control measures (including a best available 

control technology [BACT] analysis and determination) to ensure protection of air quality resources, and 

to demonstrate that the combined impacts of all PSD sources will not exceed the allowable incremental 

air quality impacts for NO2, PM10, and SO2. Minor sources with emissions below the cutoff rates 

mentioned above do not require PSD permits; nevertheless, their emissions contribute to increment 

consumption. 

A regulatory PSD Increment Consumption analysis may be conducted as part of a New Source Review, 

or independently (the WDEQ-AQD is conducting a PSD Increment Consumption analysis in southwest 

Wyoming for NO2). The determination of PSD increment consumption is a legal responsibility of the 

applicable air quality regulatory agencies, with EPA oversight. In addition, an analysis of cumulative 

impacts resulting from all existing sources and the permit applicant’s sources is also required during New 

Source Review to demonstrate that applicable ambient air quality standards will be met during the 

operational lifetime of the permit applicant’s operations. 

Sources subject to the PSD permit review procedure are also required to demonstrate potential impacts on 

Air Quality Related Values (AQRV). These include visibility impacts, degradation of mountain lakes 

from atmospheric deposition (i.e., acid rain), and effects on sensitive flora and fauna in PSD Class I and 

Class II areas. The CAA also provides specific visibility protection procedures for the mandatory federal 

Pinedale RMP A19-7 
Appendix 19 Final EIS 

PSD Class I areas designated by the U.S. Congress on August 7, 1977, which included wilderness areas 

greater than 5,000 acres in size, as well as national parks and national memorial parks greater than 6,000 

acres in size as of that date. 

AGENCY ROLES AND AUTHORITIES

Environmental Protection Agency 

The EPA administers the federal CAA, (42 United States Code [USC] 7401 et seq.) to maintain the 

NAAQS that protect human health and to preserve the rural air quality in the region by ensuring that the 

PSD Class I and Class II increments for SO2, NO2 and PM10 are not exceeded. EPA has delegated this 

CAA authority to the State of Wyoming. 

Wyoming Department of Environmental Quality 

Wyoming regulates pollutants emitted into the air through the Wyoming Environmental Quality Act 

(W.S. 35-11-101 et. seq.). Wyoming is also authorized by an approved SIP to administer all requirements 

of the PSD permit program under the CAA. In addition, the approved Wyoming SIP contains a number of 

programs that provide for the implementation, maintenance, and enforcement of the NAAQS, including a 

New Source Review program for minor source permitting, which includes among its requirements 

application of BACT for all new or modified sources, regardless of size or source category. Included as 

well are authorities for the control of particulate emissions, including fugitive particulate emissions from 

haul roads, access roads, or general facility boundaries. Wyoming is also delegated responsibility to 

operate an approved ambient air quality monitoring network for the purpose of demonstrating compliance 

with the NAAQS and WAAQS. 

Bureau of Land Management 

NEPA requires that federal agencies consider mitigation of direct, indirect, and cumulative impacts 

during their preparation of an EIS (BLM Land Use Planning Manual 1601). Under the CAA, federal 

agencies are to comply with SIPs regarding the control and abatement of air pollution. Prior to approval 

of Resource Management Plans (RMP) or amendments to RMPs, the State Director is to submit any 

known inconsistencies with SIPs to the governor of that state. If the Governor of the state recommends 

changes in the proposed RMP or amendments to meet SIP requirements, the State Director shall provide 

the public an opportunity to comment on those recommendations (BLM Land Use Planning Manual in 

Section 1610.3-2). 

U.S. Forest Service 

The USFS administers national forests, which include four wilderness areas (WA) with mandatory federal 

PSD Class I designation: Teton WA, Bridger WA, Fitzpatrick WA; and Washakie WA. In addition, the 

Class II Popo Agie and Wind River Roadless Areas need to be included in the planning area analysis. As 

Federal Land Managers (FLM), the USFS could act in a consultative role to recommend that BLM impact 

analysis results, or any future EPA or state-administered PSD refined impact analysis results (if justified), 

trigger adverse impairment status. Should the USFS determine impairment of WAs, BLM, the state, 

and/or EPA may need to mitigate this predicted adverse air quality effect. 

A19-8 Pinedale RMP 
Final EIS Appendix 19 

National Park Service 

Grand Teton National Park and Yellowstone National Park could experience direct effects associated with 

the Pinedale Field Office BLM emissions. As FLMs, the NPS could act in a consultative role to 

recommend that BLM impact analysis results, or any future EPA or state-administered PSD refined 

impact analysis results (if justified), trigger adverse impairment status. Should the NPS determine 

impairment of NPS-administered PSD Class I areas, BLM, the state, and/or EPA may need to mitigate 

this predicted adverse air quality effect. 

EXISTING AIR QUALITY

As described in Chapter 3, Affected Environment (Air Resources), specific air quality monitoring is not 

conducted throughout most of the planning area. Table A19-3 summarizes the ambient air quality 

background concentrations in the planning area. This information was provided by the WDEQ. Although 

monitoring is primarily conducted in urban or industrial areas, the data selected are considered to be the 

best available representation of background air pollutant concentrations throughout the planning area. The 

assumed background pollutant concentrations are below applicable ambient air quality standards for all 

pollutants and averaging times. However, ozone levels approach the 84 ppb standard (at the time of this 

writing). These national and Wyoming standards, and PSD increment values are also presented in Table 

A19-1 and Table A19-2. 

Pinedale RMP A19-9 
Appendix 19 Final EIS 

Table A19-3. Assumed Background Concentrations, Applicable Ambient Air Quality 

Standards, and PSD Increment Values (in μg/m3) 

Percent of Standards Data 

Pollutant/Averaging 

Time Measured 

Measured 

Background 

Concentration 

μg/m3 

NAAQS WAAQS 

Data Source 

Carbon Monoxide (CO) 

1-hour 1,979 5 5 

8-hour 931 9 9 

Data collected in 

Yellowstone 

National Park, WY, 

monitoring site near 

“Old Faithful” during 

2005. (Pinedale 

Anticline Draft 

Supplement EIS, 

2006). 

Nitrogen Dioxide (NO2) 

Annual 19.1 6 6 

Data collected in the 

Jonah Field, 

approximately 40 

miles northwest of 

Farson, Sublette 

County, Wyoming. 

Values are based on 

a partial year of data 

(Jan 15 to Dec 31) 

collected during 

2005. (Pinedale 

Anticline Draft 

Supplement EIS, 

2006). 

Ozone 

8-hour 152 97 97 

Data collected in the 

Jonah Field, 

approximately 40 

miles northwest of 

Farson, Sublette 

County, Wyoming. 

Values are based on 

a partial year of data 

(Jan 15 to Dec 31) 

collected during 

2005. (Pinedale 

Anticline Draft 

Supplement EIS, 

2006). 

A19-10 Pinedale RMP 
Final EIS Appendix 19 

Pollutant/Averaging 

Time Measured 

Measured 

Background 

Concentration 

μg/m3 

Percent of Standards Data Data Source 

Particulate Matter (PM 10)

a

24-hour 51 34 34 

Annual 10 NA NA 

Data collected in the 

Jonah Field, 

approximately 40 

miles northwest of 

Farson, Sublette 

County, Wyoming. 

Values are based on 

a partial year of data 

(Jan 15 to Dec 31) 

collected during 

2005. (Pinedale 

Anticline Draft 

Supplement EIS, 

2006). 

Particulate Matter (PM 2.5)

a

24-hour 18 51 28 

Annual 6.5 43 43 

Data collected in the 

Jonah Field, 

approximately 40 

miles northwest of 

Farson, Sublette 

County, Wyoming. 

Values are based on 

a partial year of data 

(Jan 15 to Dec 31) 

collected during 

2005. (Pinedale 

Anticline Draft 

Supplement EIS, 

2006). 

Sulfur Dioxide (SO2) 

3-hour 93 7 13 

24-hour 32 9 12 

Annual 4 1 1 

Data collected at the 

Lost Cabin Gas 

Plant 

Preconstruction 

Monitoring in 

Fremont County 

1986-1987. 

On September 21, 2006, EPA announced final revisions to NAAQS standards for particulate matter. The 

revision strengthens the 24-hour PM2.5 standard from 65 to 35 ug/m3 and revokes the annual PM10

standard of 50 ug/m3

. EPA retained the existing annual PM2.5 standard of 15 ug/m3 and the 24-hour PM10

standard of 150 ug/m3

. The ozone 8-hour NAAQS and WAAQS was 84 ppb until March 12, 2008; on that 

date, the 8-hour NAAQS for ozone was revised to 75 ppb. After the final rule becomes effective, the State 

of Wyoming will enter into rulemaking to revise the WAAQS. 

Air Quality Impact Assessment 

As described in Chapter 4, Environmental Consequences (Air Quality), a qualitative emission comparison 

approach was used. The emissions calculations were based on the best available engineering data and 

Pinedale RMP A19-11 
Appendix 19 Final EIS 

assumptions; air, visibility, and atmospheric deposition data; and emission inventory procedures, as well 

as professional and scientific judgment. However, when specific data or procedures were not available, 

assumptions were applied. (see emission assumptions, page A19-13.) 

Maximum potential near-field particulate matter emissions from traffic on unpaved roads and during well 

pad construction were used to estimate emissions for PM2.5 and PM10 impacts. Maximum air pollutant and 

particulate emissions from each oil and gas well pad would be temporary (i.e., occurring during a 12-day 

construction period) without significantly interacting with adjacent well locations. Particulate matter 

emissions from well pad and resource road construction would be minimized by application of water 

and/or chemical dust suppressants. The control efficiency of these dust suppressants was estimated at 

50% during construction. During well completion testing, natural gas could be burned (flared) for 1 to 6 

days. For any future projects, significance criteria for potential air quality impacts will include local, state, 

tribal, and federally enforced legal requirements to ensure air pollutant concentrations remain within 

specific allowable levels. These requirements and legal limits were presented in Table A19-1. Because 

neither the WDEQ-AQD nor EPA has established ambient HAP standards, only emissions were 

calculated. 

Flaring is a permitted action and done so by the WDEQ (which regulates emissions from project 

components) under the authority of the Wyoming Air Quality Standards and Regulations. The Wyoming 

Oil and Gas Conservation Commission (WOGCC) also has some authority to regulate this type of action, 

under WOGCC Rule: Chapter 3, Section 40. 

Because the potential air pollutant emission sources constitute many small sources spread over a very 

large area, discrete visible plumes are not likely to affect the distant sensitive areas. However, the 

potential for cumulative visibility impacts (from increased regional haze) are a concern. Degradation in 

visibility is caused by increases in the concentration of fine particles and gases that scatter and absorb 

light. Potential changes to regional haze are calculated in terms of a perceptible “just noticeable change” 

(1.0 dv) in visibility when compared with background conditions. A 1.0-dv change is considered 

potentially significant in mandatory federal PSD Class I areas, as described in the EPA Regional Haze 

Regulations (40 CFR §51.300 et seq.) and as originally presented in Pitchford and Malm (1994). A 1.0-dv 

change is defined as about a 10% change in the extinction coefficient (corresponding to a 2% to 5% 

change in contrast, for a black target against a clear sky, at the most optically sensitive distance from an 

observer), which is a small but noticeable change in haziness under most circumstances when viewing 

scenes in mandatory federal PSD Class I areas. 

It should be noted that a 1.0-dv change is not a “just noticeable change” in all cases for all scenes. 

Visibility changes of less than 1.0 dv are likely to be perceptible in some cases, especially when the scene 

being viewed is highly sensitive to small amounts of pollution, such as that caused by preferential forward 

light scattering. Under other view-specific conditions, such as when the sight path to a scenic feature is 

less than the maximum visual range, a change greater than 1.0 dv might be required to be a “just 

noticeable change.” However, any future project-specific NEPA analyses will not be designed to predict 

specific visibility impacts for specific views in specific mandatory federal PSD Class I areas based on 

specific project designs, but rather to characterize reasonably foreseeable visibility conditions that are 

representative of a fairly broad geographic region, based on emission source assumptions. This approach 

is consistent with the nature of regional haze and the requirements of NEPA. At the time of a preconstruction air quality PSD permit review, the WDEQ-AQD may require a much more detailed visibility 

impact analysis. Factors such as the magnitude of change, frequency, time of the year, and the 

meteorological conditions during times when predicted visibility impacts are above the 1.0-dv threshold 

(as well as inherent conservatism in the impact analyses) should all be considered when assessing the 

significance of predicted impacts. 

A19-12 Pinedale RMP 
Final EIS Appendix 19 

The USFS, NPS, and USFWS have published their “Final FLAG Phase I Report” (Federal Register, Vol. 

66, No. 2, January 3, 2001), providing “a consistent and predictable process for assessing the impacts of 

new and existing sources on AQRVs” including visibility. For example, the FLAG report states “A 

cumulative effects analysis of new growth (defined as all PSD increment-consuming sources) on visibility 

impairment should be performed,” and further, “If the visibility impairment from the proposed action, in 

combination with cumulative new source growth, is less than a change in extinction of 10% [1.0 dv] for 

all time periods, the FLMs will not likely object to the proposed action.” 

Estimation of Emission Factors 

For natural gas compressor engines, the emissions of nitrogen oxides, CO, and formaldehyde are 

determined by the average permitted emission rate allowed by the state under BACT processes. For 

fugitive dust impacts, emission rates are obtained from EPA’s AP-42 document entitled A Compilation 

of Air Pollutant Emission Factors. An AP-42 emission factor is a representative value that is an attempt 

to relate the quantity of a pollutant released to the atmosphere to an activity associated with the release of 

that pollutant. Emission factors may be appropriate to use in a number of situations such as making 

source-specific emission estimates for areawide inventories. These inventories have many purposes, 

including ambient dispersion modeling and analysis, control strategy development, and in screening 

sources for compliance investigations. In most cases, these factors are simply averages of all available 

data of acceptable quality and are generally assumed to be representative of long-term averages for all 

sources in a specific category. 

Emission Assumptions 

When reviewing the emission inventory, it is important to understand that assumptions were made 

regarding development. For example, there is uncertainty regarding ultimate development of energy 

resources (i.e., number of wells, equipment to be used, specific locations of wells, etc.). 

For the qualitative emission comparison approach, the following assumptions were used: 

• All emission sources are assumed to operate at their reasonably foreseeable maximum emission 

rates (as identified in the other resource sections of this document), simultaneously throughout the 

area. Given the number of sources included in this analysis, the co-probability of such a scenario 

actually occurring over an entire year (or even 24 hours) is small. 

• In developing the emissions inventory, there is uncertainty regarding ultimate development (i.e., 

number of wells, equipment to be used, specific locations, etc.). All proposed gas wells were 

assumed to be fully operational and remain operating, except for normal well closures throughout 

the area. (Well numbers were provided by the BLM Reservoir Management Group.) 

• The emissions inventory uses peak years of construction and peak years of operations, which 

would not occur throughout the entire development region at the same time. However, it is 

possible that conditions close to these could occur in some isolated areas. In addition, it is 

assumed that the maximum cumulative emissions will occur in the last year (2021) of the 

analysis. 

• The South Piney EIS estimates for compressor engines are used in this RMP (McVehil-Monnett 

Associates 2004) and are 170 horse power (hp) per well in a conventional gas field and 250 hp 

per well for methane compression in a coal field. 

• Mitigation measures are included in the emissions inventory that may not be achievable in all 

circumstances. However, actual mitigation decided upon by the developers and local and state 

Pinedale RMP A19-13 
Appendix 19 Final EIS 

authorities may be greater or lesser than those assumed in the analysis. For example, maintaining 

a construction road speed limit of 15 miles per hour (mph) may be reasonable in a construction 

zone but difficult to enforce elsewhere. Full (100%) mitigation of fugitive dust from disturbed 

lands may not be achievable. Further, 50% reduction in fugitive emissions is assumed based on 

construction road wetting on the unimproved access road to the pad and at the pad, but this level 

of effectiveness is characterized as the maximum possible. Wetting was assumed for maintenance 

traffic. 

• Induced or secondary growth related to increases in vehicle miles traveled (VMT) is not included 

in the emissions inventory. Only activities directly related to BLM actions are considered. (An 

example of ‘secondary’ development is where growth of workers causes growth of more people 

to support them, such as shopping centers. Growth of air emissions would occur to secondary 

activities; such as, workers traveling to the store or to recreational activities.) 

The major assumptions used in developing the emissions calculations are— 

• Except for those emission factors that have been lowered through the WDEQ-AQD BACT 

requirements, EPA-recommended emission factors (i.e., AP-42) are appropriate for all activities. 

• The base year is 2001. 

• Activity factors (or the quantification of activity for each resource program as provided by the 

Pinedale Field Office) are appropriate for the base year and future time frames. 

• Any anticipated recreational growth would follow growth trends for Wyoming over the past 10 

years. 

• For the qualitative analysis, only emissions from Pinedale Field Office BLM-administered 

activities are included. (For the cumulative analysis, emissions calculated by TRC (TRC 2004) 

are included for other federal and non-federal actions throughout the state.) 

• Criteria pollutants and HAPs are included in the calculations. 

• No trona mining activity occurs in the planning area. 

Emissions were calculated for the following activities: lands and realty actions, livestock grazing, offhighway vehicles (OHV), resource roads, saleable minerals, vegetation, fire, and natural gas development. 

Activities related to weed control, and wildlife and fisheries are assumed to be insignificant sources of air 

emissions. 

A qualitative emission comparison approach was selected for this RMP air quality analysis. This 

approach was used because: (1) sufficient specific data were not available on future projects; (2) as 

projects are defined, quantitative analysis will be required; and (3) WDEQ-AQD will require 

demonstration of compliance for any future specific projects. There are limitations associated with this 

approach. However, given the uncertainties with the number, nature, and specific location of future 

sources and activities, the emission comparison approach is defensible and provides a sound basis to 

compare alternatives. 

It is important to note that before actual development could occur, the applicable air quality regulatory 

agencies (including the state, tribe, or EPA) would review specific air pollutant emissions preconstruction 

permit applications that examine potential project-specific air quality impacts. As part of these permit 

reviews (depending on source size), the air quality regulatory agencies could require additional air quality 

impact analyses or mitigation measures. Thus, before development occurs, additional site-specific air 

A19-14 Pinedale RMP 
Final EIS Appendix 19 

quality analyses would be performed to ensure protection of air quality. FLMs will require a 

demonstration that potential impacts from proposed projects will not adversely affect AQRVs (including 

visibility) in PSD Class I and sensitive Class II areas. 

Emissions Calculations 

Emissions for All Activities Except Fire 

A summary of emission inventories for each of the BLM activities for the base year, short-term, and longterm scenarios for all of the alternatives are found in Chapter 4. These emissions were calculated from 

data provided by the Pinedale Field Office and used the best available information, BACT, AP-42, and 

the emission studies from other BLM documents. 

The assumed numbers of oil and gas wells are provided by the Pinedale Field Office and are shown in 

Table A19-4. This table accounts for new wells to be drilled in the planning area. 

Table A19-4. Numbers of Oil and Gas Wells for the Pinedale Field Office 

Well Type Existing Wells 

Through 2001 

2011 Operational 

Wells 

2021 Operational 

Wells 

Alternative 1 (No Action Alternative) 

Total Coalbed Natural Gas (CBNG) 

Wells 5 256 512 

Total Conventional Gas Wells 2,168 3,964 7,927 

Total Combined Wells 2,173 4,220 8,439 

Alternative 2 

Total CBNG Wells 5 293 586 

Total Conventional Gas Wells 2,168 4,233 8,465 

Total Combined Wells 2,173 4,526 9,051 

Alternative 3 

Total CBNG Wells 5 191 382 

Total Conventional Gas Wells 2,168 3,037 6,074 

Total Combined Wells 2,173 3,228 6,456 

Alternative 4 (Proposed RMP) 

Total CBNG Wells 5 224 547 

Total Conventional Gas Wells 2,168 3,918 7,836 

Total Combined Wells 2,173 4,192 8,383 

Using the well numbers and a well abandonment rate of 12%, individual tables of air emissions for all 

BLM activities were calculated in linked spreadsheets. These spreadsheets are available on compact disc 

(CD) at the BLM Pinedale Field Office or Wyoming State Office (see Table A19-5 for a table of contents 

for the information on the CD). 

Because oil and gas field activities comprise many phases (i.e., exploration, development, production, and 

closure), the components that need to be included in emission calculations are complex. Table A19-5 

Pinedale RMP A19-15 
Appendix 19 Final EIS 

presents a summary list of what is included on the emissions CD to provide an understanding of the 

elements and assumptions used in the emissions calculations. 

Table A19-5. Table of Contents for Emissions CD 

Tab Name Tab Description 

Assumptions 

Conventional Oil and Gas Assumptions 

ng-pad const.-fug dust Well Pad Construction and Fugitive Dust Short- and LongTerm Development 

Well Field Gas Charac Well Field Gas Characteristics 

ng-pad const. exh & flare-shrt Well Pad Construction, Equipment Exhaust, and Well 

Completion Flaring, Short-Term Development 

ng-pad const. exh & flare-long Well Pad Construction, Equipment Exhaust, and Well 

Completion Flaring, Long-Term Development 

ng-commuting veh-fug dust-shrt Well Pad Construction, Commuting Vehicles, Fugitive Dust, 

Short-Term Development 

ng-commuting veh-fug dust-long Well Pad Construction, Commuting Vehicles, Fugitive Dust, 

Long-Term Development 

ng-commuting veh-exhaust-shrt Well Pad Construction, Commuting Vehicles, Exhaust, ShortTerm Development 

ng-commuting veh-exhaust-long Well Pad Construction, Commuting Vehicles, Exhaust, LongTerm Development 

ng-Operations-NG compress-shrt Well Pad Operations, Natural Gas Compressors, Short-Term 

Development 

ng-Operations-NG compress-long Well Pad Operations, Natural Gas Compressors, Long-Term 

Development 

ng-Op NG Dehyd&Flash&Flare Well Pad Operations, Dehydrators and Tank Flashing and 

Flaring, Short- and Long-Term Development 

ng-Ops-Dehyd&Sep-heaters Well Pad Operations, Glycol Dehydrators and Three-Phase 

Separator Heaters, Short- and Long-Term Development 

ng-Ops-sta. vis-dust&exh-short Well Pad Operations, Station Visits, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

ng-Ops-sta. vis-dust&exh-long Well Pad Operations, Station Visits, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 

ng-Ops-WO-dust&exh-short Well Pad Operations, Well Workover, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

ng-Ops-WO-dust&exh-long Well Pad Operations, Well Workover, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 

ng-Ops W&P vis-dust&exh-shrt Well Pad Operations, Well and Pipe Visits, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

ng-Ops W&P vis-dust&exh-long Well Pad Operations, Well and Pipe Visits, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 

ng-Road maint-dust&exh-shrt Well Pad Maintenance Roads, Fugitive Dust and Vehicle 

Exhaust, Short-Term Development 

ng-Road maint-dust&exh-long Well Pad Maintenance Roads, Fugitive Dust and Vehicle 

Exhaust, Long-Term Development 

A19-16 Pinedale RMP 
Final EIS Appendix 19 

Pinedale RMP A19-17 

Tab Name Tab Description 

ng-Comp maint-dust&exh-short Well Pad Maintenance Compressors, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

ng-Comp maint-dust&exh-long Well Pad Maintenance Compressors, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 

Tanks Condensate & Loadout Well Pad Operations, Condensate Tanks, VOC Emissions, 

Short- and Long-Term Development 

ng-summary-criteria-short Natural Gas Development, Summary of Short-Term 

Development, Emissions 

Annual Summary 2011 Natural Gas Development Annual Emissions Summary 2011 

Annual Summary 2021 Natural Gas Development Annual Emissions Summary 2021 

ng-summary-criteria-long Natural Gas Development Summary of Long-Term 

Development Emissions 

Assumptions 

CBNG Wells Inputs and Assumptions 

CBNG-pad const.-fug dust Well Pad Construction and Fugitive Dust Short- and LongTerm Development 

CBNG-Well Field Gas Charac Well Field Gas Characteristics 

CBNG-pad const. traff-exh-shrt Well Pad Construction, Equipment Exhaust, Short-Term 

Development 

CBNG-pad const. traff-exh-long Well Pad Construction, Equipment Exhaust, Long-Term 

Development 

CBNG-commut veh-fug dust-shrt Well Pad Construction, Commuting Vehicles, Fugitive Dust, 

Short-Term Development 

CBNG-commut veh-fug dust-long Well Pad Construction, Commuting Vehicles, Fugitive Dust, 

Long-Term Development 

CBNG-commut veh-exhaust-shrt Well Pad Construction, Commuting Vehicles, Exhaust, ShortTerm Development 

CBNG-commut veh-exhaust-long Well Pad Construction, Commuting Vehicles, Exhaust, LongTerm Development 

CBNG-Ops-NG compress-shrt Well Pad Operations, Natural Gas Compressors, Short-Term 

Development 

CBNG-Ops-NG compress-long Well Pad Operations, Natural Gas Compressors, Long-Term 

Development 

CBNG-Dehy Shrt&long Well Pad Operations, Dehydrators, Short- and Long-Term 

Development 

CBNG-Ops-Sep Dehy-shrt&long Well Pad Operations, Separator Heaters and Dehydrators, 

Short- and Long-Term Development 

CBNG-Ops-sta. vis-dust&exh-shrt Well Pad Operations, Station Visits, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

CBNG-Ops-sta. vis-dust&exh-long Well Pad Operations, Station Visits, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 

CBNG-Ops-WO-dust&exh-short Well Pad Operations, Well Workover, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

CBNG-Ops-WO-dust&exh-long Well Pad Operations, Well Workover, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 
Appendix 19 Final EIS 

A19-18 Pinedale RMP 

Tab Name Tab Description 

CBNG-Ops W&P vis-dust&exh-shrt Well Pad Operations, Well and Pipe Visits, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

CBNG-Ops W&P vis-dust&exh-long Well Pad Operations, Well and Pipe Visits, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 

CBNG-road maint-dust&exh-shrt Well Pad Maintenance Roads, Fugitive Dust and Vehicle 

Exhaust, Short-Term Development 

CBNG-road maint-dust&exh-long Well Pad Maintenance Roads, Fugitive Dust and Vehicle 

Exhaust, Long-Term Development 

CBNG-Comp maint-dust&exh-short Well Pad Maintenance Compressors, Fugitive Dust and 

Vehicle Exhaust, Short-Term Development 

CBNG-Comp maint-dust&exh-long Well Pad Maintenance Compressors, Fugitive Dust and 

Vehicle Exhaust, Long-Term Development 

CBNG Water Reinjection Well Pad CBNG Water Reinjection Short- and Long-Term 

Development 

CBNG-summary-criteria-short CBNG Summary of Short-Term Development Emissions 

Annual CBNG Summary 2011 CBNG Annual Emissions Summary 2011 

Annual CBNG Summary 2021 CBNG Annual Emissions Summary 2021 

CBNG-summary-criteria-long CBNG Summary of Long-Term Development Emissions 

Lands and Realty 

L&R-heavyequip-dust-shrt&long 

L&R-heavyequip-exh-shrt&long 

L&R-Commuting-FugDust-short 

L&R-Commuting-FugDust-long 

L&R-Commuting-exhaust-short 

L&R-Commuting-exhaust-long 

Summary-short 

Summary-long 

Livestock Grazing 

LG-heavyequip-dust-shrt&long 

LG-heavyequip-exh-shrt&long 

LG-Commuting-FugDust-shortunpav 

LG-Commuting-FugDust-shortpaved 

LG-Commuting-FugDust-longunpav 

LG-Commuting-FugDust-longpaved 

LG-Commuting-exhaust-short 

LG-Commuting-exhaust-long 

Summary-short 

Summary-long 

Off-Highway Vehicles 

ATVs 
Final EIS Appendix 19 

Pinedale RMP A19-19 

Tab Name Tab Description 

OH Motorcycles 

Snowmobiles 

OHV-Summary 

Resource Roads 

res road-dust&exh-short 

res road-dust&exh-long 

Salable Minerals 

sg-dry,hand,screen,load,etc. 

sg-unpaved roads 

sg-batchdrop 

heavy equipment-all operations 

gran-crush,screen,tx,etc 

gran-unpaved roads 

granite-batchdrop 

lime-crush,screen,tx,etc 

lime-unpaved roads 

limestone-batchdrop 

saleable-summary 

Vegetation 

Veg-heavyequip-dust-shrt&long 

Veg-heavyequip-exh-shrt&long 

Veg-Commuting-FugDust-short 

Veg-Commuting-FugDust-long 

Veg-Commuting-exhaust-short 

Veg-Commuting-exhaust-long 

Summary-short 

Summary-long 

The tables are linked spreadsheets with emissions calculations for the short-term and long-term timeframes. Each set of 

calculations for the non-oil and gas spreadsheets are cumulative, that is, the total emissions for all activities are cumulative for 10 

and 20 years, respectively. At the beginning of each spreadsheet, the emission factors and activity factors are identified in 

tabular format. 

The detailed emissions tables identified above are available on request from Susan Caplan. 

(Same analysis and tabs for Base Year as above for 2001) 

Prescribed Fire Emissions Estimation 

To estimate the total emissions of particulate matter and CO from prescribed fires, the Simple Approach 

Smoke Estimation Model (SASEM) was used. SASEM is a simple screening level Gaussian dispersion 

model designed to predict ground-level particulate matter impacts from a single source (fire) in generally 

flat terrain for the western United States. 
Appendix 19 Final EIS 

Where possible, site-specific information, as provided by the Pinedale Field Office, was used as input to 

the model. Where such information was not available, either built-in model defaults or professional 

judgment were used to supply missing data. Because detailed data on vegetation control and burning were 

lacking, field office personnel estimates were used. It is assumed that 500 acres per year are burned. 

It should be noted that the Emission Production Module (EPM) of SASEM was used only to estimate 

total emissions for each event as input to the qualitative air quality assessment. (see references in Chapter 

4, Sestak and Riebau 1988.) 

The detailed results for these model runs are available from John Zachariassen. 

Planning Area BLM Emissions 

Table A19-6 through Table A19-8 show the summary of total BLM emissions estimated for the base year 

(2001), the short term (2011), and the long term (2021). The tables are broken down by activity for each 

pollutant for emissions within the timeframe referenced (i.e., base year, short term, and long term). The 

emissions are calculated on an annual basis (i.e., tons per year). Emissions were calculated for each 

alternative. Because the base year results are the same for all alternatives, only one set of base year 

emissions was needed. These tables were used to generate the summary tables for Chapter 4. 

Table A19-6. Base Year (2001) Emissions Inventory for BLM-Administered 

Lands Within the Planning Area (tons per year) 

Activity PM10 

Tons 

PM2.5 

Tons 

NOx 

Tons 

SO2

Tons 

CO 

Tons 

VOC 

Tons 

HAPs 

Tons 

Base Case 

Coalbed Natural Gas 70 39 226 3 248 120 20 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 27 15 2 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 82 44 4 

Conventional Natural Gas 1,608 886 7,492 87 8,503 13,298 1,579 

Total Base Year 2001 2,065 1,031 7,724 90 8,833 13,462 1,603 

Table A19-7. Short-term (2011) Emissions Inventory for BLM-Administered 

Lands Within the Planning Area (tons per year) 

Activity PM10 

Tons 

PM2.5 

Tons 

NOx 

Tons 

SO2

Tons 

CO 

Tons 

VOC 

Tons 

HAPs 

Tons 

Alternative 1 (Continuation of Existing Management) 

Coalbed Natural Gas 279 216 1,326 7 2,384 1,389 217 

Lands and Realty 186 28 4 0 21 22 2 

A19-20 Pinedale RMP 
Final EIS Appendix 19 

Pinedale RMP A19-21 

Activity PM10 

Tons 

PM2.5 

Tons 

NOx 

Tons 

SO2

Tons 

CO 

Tons 

VOC 

Tons 

HAPs 

Tons 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 76 29 3 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 97 51 5 

Conventional Natural Gas 2,696 1,899 13,995 110 18,802 30,301 3,650 

Total Short Term 3,362 2,221 15,327 117 21,283 31,741 3,872 

Alternative 2 

Coalbed Natural Gas 319 249 1,514 8 2,722 1,585 247 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 76 29 3 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 97 51 5 

Conventional Natural Gas 2,834 1,987 14,685 117 20,693 31,643 3,811 

Total Short Term 3,540 2,342 16,205 125 23,512 33,279 4,063 

Alternative 3 

Coalbed Natural Gas 210 164 995 5 1,790 1,843 163 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 76 29 3 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 97 51 5 

Conventional Natural Gas 2,223 1,596 11,619 88 16,733 25,274 3,054 

Total Short Term 2,820 1,866 12,620 93 18,620 27,168 3,222 

Alternative 4 (Proposed RMP) 

Coalbed Natural Gas 298 232 1415 7 2,544 1,482 231 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 
Appendix 19 Final EIS 

A19-22 Pinedale RMP 

Activity PM10 

Tons 

PM2.5 

Tons 

NOx 

Tons 

SO2

Tons 

CO 

Tons 

VOC 

Tons 

HAPs 

Tons 

OHV 1 1 0 0 76 29 3 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 97 51 5 

Conventional Natural Gas 2,629 1,880 13,661 105 19,600 29,939 3,609 

Total Short Term 3,314 2,218 15,082 112 22,241 31,472 3,845 

a PM2.5 assumed = PM10 for this activity. b HAP assumed = VOC × 0.1 for non-oil and gas activities 

Table A19-8. Long-Term (2021) Emissions Inventory for BLM-Administered 

Lands Within the Planning Area (tons per year) 

Activity PM10 

Tons 

PM2.5 

Tons 

NOx 

Tons 

SO2

Tons 

CO 

Tons 

VOC 

Tons 

HAPs 

Tons 

Alternative 1 (Continuation of Existing Management) 

Coalbed Natural Gas 496 420 2512 10 4,695 2,745 428 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 94 35 4 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 115 57 6 

Conventional Natural Gas 3,946 3,004 21,006 135 28,100 47,178 5,800 

Total Long Term 4,829 3,530 23,524 145 32,910 49,980 6,234 

Alternative 2 

Coalbed Natural Gas 567 480 2,872 12 5,367 3,138 490 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 94 35 4 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 105 57 6 
Final EIS Appendix 19 

Pinedale RMP A19-23 

Activity PM10 

Tons 

PM2.5 

Tons 

NOx 

Tons 

SO2

Tons 

CO 

Tons 

VOC 

Tons 

HAPs 

Tons 

Conventional Natural Gas 4,180 3,169 22,172 144 29,557 49,666 5,614 

Total Long Term 5,134 3,755 25,050 156 35,029 52,881 6,110 

Alternative 3 

Coalbed Natural Gas 375 315 1,880 8 3515 2,055 321 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 94 35 4 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 105 57 6 

Conventional Natural Gas 3,150 2,443 16,991 107 26,086 39,044 4,738 

Total Long Term 3,912 2,864 18,877 115 29,706 41,156 5,065 

Alternative 4 (Proposed RMP) 

Coalbed Natural Gas 535 449 2,502 11 5,013 2,931 457 

Lands and Realty 186 28 4 0 21 22 2 

Livestock Grazing 18 3 1 0 0 0 0 

OHV 1 1 0 0 94 35 4 

Resource Roads 1 0 1 0 0 0 0 

Salable Minerals 129 28 0 0 0 0 0 

Vegetation 1 0 0 0 0 0 0 

Fire 51 46 0 0 0 0 0 

Subtotal: Other Activities 387 106 6 0 105 57 6 

Conventional Natural Gas 3,878 2,974 20,662 131 31,683 47,434 5,755 

Total Long Term 4,800 3,529 23,170 142 36,801 50,422 6,218 

a PM2.5 assumed = PM10 for this activity. b HAP assumed = VOC × 0.1 for non-oil and gas activities 

RESULTS OF IMPACT ANALYSIS 

Table A19-9 summarizes the existing conditions presented in Chapter 3, Affected Environmental (Air 

Quality). 
Appendix 19 Final EIS 

Table A19-9. Existing Conditions 

Existing Conditions 

Air Pollutant Concentrations 

Criteria Air 

Pollutants • Concentrations are in compliance with NAAQS and WAAQS. 

Nitrogen 

Compounds 

• HNO3 concentrations in Pinedale are consistent with concentrations in other remote 

areas. HNO3 concentrations in Yellowstone National Park are consistent with other 

remote areas. 

• Concentrations of NO3 and NH4 in Pinedale and Yellowstone National Park are 

consistent with other remote areas. 

Sulfur Compounds 

• SO2 concentrations in Pinedale are below concentrations typical in remote areas. SO2

concentrations in Yellowstone National Park are consistent with other remote areas. 

• SO4

-- concentrations in Pinedale and Yellowstone National Park are below typical 

concentrations in remote areas. 

Visibility 

Bridger Wilderness 

• 20% cleanest—155–175 miles 

• Average—112–128 miles 

• 20% haziest—71–90 miles 

Atmospheric Deposition 

Precipitation pH 

• Slight precipitation acidification in Pinedale from 1994 through 2004 (pH as low as 4.9) 

• Precipitation near-natural in Yellowstone National Park from 1980 through 2004 (pH: 

5.1–5.7) 

Total Deposition 

• Pinedale: nitrogen deposition from ammonium (NH4

+

) and nitrate (NO3-) is less than 

2.0 kg/ha/yr.

2

 Sulfur deposition from sulfate (SO4

--) and sulfur dioxide (SO2) is less 

than 1.7 kg/ha/yr.3

The emission inventory results and qualitative impacts for the alternatives are included in Chapter 4, and 

total emissions are shown in Table 19-10. Table A19-11 shows the increases in emissions from 

alternative to alternative, and year to year. 

Table 19-10. Total Emissions for Alternatives (tons per year) 

Constituent Emissions (tons per year) Year 

PM10 NOx SO2 CO VOC HAP 

Total 

Alternative 1 (Continuation of Existing Management) 

2001 2065 7724 90 8833 13462 1603 33777 

2011 3362 15327 117 21283 31741 3872 75702 

2021 4829 23524 145 32910 49980 6234 117622 

Alternative 2 

2001 2065 7724 90 8833 13462 1603 33777 

2011 3540 16205 125 23512 33279 4063 80724 

2021 5134 25050 156 35029 52881 6110 124360 

Alternative 3 

2001 2065 7724 90 8833 13462 1603 33777 

A19-24 Pinedale RMP 
Final EIS Appendix 19 

Pinedale RMP A19-25 

Constituent Emissions (tons per year) Year 

PM10 NOx SO2 CO VOC HAP 

Total 

2011 2820 12620 93 18620 27168 3222 64543 

2021 3912 18877 115 29706 41156 5065 98831 

Alternative 4 (Proposed RMP) 

2001 2065 7724 90 8833 13462 1603 33777 

2011 3314 15082 112 22241 31472 3845 76066 

2021 4800 23170 142 36801 50422 6218 121553 

Table A19-11. Increase in Annual Air Emissions from Base Year Conditions on BLMAdministered Lands Within the Planning Area 

Time 

Frame PM10

 a PM2.5 a NOx a SO2 a CO a VOC a HAP a

Alternative 1 (Continuation of Existing Management) 

2011 1,297 

(63%) 

1,190 

(115%) 

7,603 

(98%) 

27 

(30%) 

12,450 

(141%) 

18,279 

(136%) 

2,269 

(142%) 

2021 2,764 

(134%) 

2,499 

(242%) 

15,800 

(205%) 

55 

(61%) 

24,007 

(273%) 

36,518 

(271%) 

4,631 

(289%) 

Alternative 2 

2011 1,475 

(71%) 

1,311 

(109%) 

8,481 

(110%) 

35 

(39%) 

14,679 

(166%) 

19,817 

(147%) 

2,460 

(153%) 

2021 3,069 

(149%) 

2,724 

(264%) 

17,326 

(224%) 

66 

(73%) 

26,196 

(297%) 

39,421 

(293%) 

4,507 

(281%) 

Alternative 3 

2011 755 

(37%) 

835 

(81%) 

4,896 

(63%) 

3 

(3%) 

9,787 

(111%) 

13,706 

(102%) 

1,619 

(101%) 

2021 1,847 

(89%) 

1,833 

(178%) 

11,153 

(144%) 

25 

(28%) 

20,873 

(236%) 

27,694 

(206%) 

3,462 

(216%) 

Alternative 4 (Proposed RMP) 

2011 1,249 

(60%) 

1,187 

(115%) 

7,358 

(95%) 

22 

(24%) 

13,408 

(152%) 

18,010 

(134%) 

2,242 

(140%) 

2021 2,735 

(132%) 

2,498 

(242%) 

15,446 

(200%) 

52 

(58%) 

27,968 

(317%) 

36,960 

(275%) 

4,615 

(288%) 

a

 Constituents increase in tons per year (and in percentage change from base year emissions) 

OTHER EMISSIONS DATA

Although only BLM activities were included in the qualitative analysis, other emissions data are being 

developed for areas that include the planning area. These data were provided by TRC Environmental 

Corp (Connell 2004) using State of Wyoming air permit information and other information, which 

includes the potential to emit (PTE) and some actual emissions for point sources throughout Wyoming 

that were permitted between January 1, 2001, and June 30, 2003. Table A19-12 and Table A19-13 show 

the calculations of the incremental increase (i.e., change from the base year) in emissions from January 1, 

2001, (the base year) through June 30, 2003, for permitted sources. 
Appendix 19 Final EIS 

The Wyoming Statewide Emission Inventory conducted by TRC indicates that there will be a change in 

future emissions of NOx, SO2, PM10, and PM2.5 in the planning area and for the State of Wyoming. This 

study uses different base year dates. The Wyoming statewide complete emissions increases (or decreases) 

were calculated (1) from all permitted sources, from January 1, 2001, through June 30, 2003, (2) all new 

oil and gas commission’s sources from 2002, and (3) all NEPA authorized and other quantifiable 

emissions from June 30, 2003. (This last case is referred to as the Wyoming Statewide Reasonably 

Foreseeable Development [RFD].) It should be noted that not all emissions permitted or authorized during 

this period are occurring yet. 

The RFD case refers only to oil and gas projects and is the change in emissions after June 30, 2003, for 

authorized NEPA and other quantifiable emissions. (Specifically, the RFD case is defined by TRC as 

“...1) the NEPA-authorized but not yet developed portions of the Wyoming NEPA projects and 2) not yet 

authorized NEPA projects for which air quality analyses were in progress and for which emissions had 

been quantified.”) Complete (total) emissions are calculated as well. Table A19-12 shows these 

emissions. It is expected that these data will someday be integrated with the BLM emissions data to 

depict all emissions in the planning area and can be used for cumulative analysis. Also, this information 

will be needed if air dispersion modeling is performed in the area. 

Table A19-12. Incremental Emissions from Permitted Sources January 2001 Through June 

2003 for the Planning Area–Values in Parentheses Are Total Emissions 

WDEQ-AQD Permitted Sources WOGCC Permitted Oil and Gas Wells2

Area Change in Emissions (tpy) Change in Emissions (tpy) 

NOx SO2 PM10 PM2.5 NOx SO2 PM10 PM2.5

Planning Area1 583 43 22 22 2 -- -- -- 

Wyoming 20,344 (85) (1,812) (1,535) 150.9 -- -- -- 

1

 Permitted oil and gas wells category includes Sublette and Teton counties. 

2 Emission factors per well were assumed according to the following: 0.045 tpy of NOx per producing natural gas or coalbed 

natural gas well, equivalent to well emission rates calculated for the Jonah Infill Project, 2004; and 0.3 tpy NOx per producing oil 

well, obtained from Denise Kohtala, WDEQ-AQD, 2003. 

Table A19-13. RFD and Complete Emissions for the Planning Area 

RFD3 Complete Inventory 

Area Change in Emissions (tpy) Change in Emissions (tpy) 

NOx SO2 PM10 PM2.5 NOx SO2 PM10 PM2.5

Planning Area1 1,135 1 82 80 1,719 44 103 102 

Wyoming 6,016 115 741 195 26,511 30 (1,072) (1,343) 

1

 Permitted oil and gas wells category includes Sublette and Teton counties. 

2 Emission factors per well were assumed according to the following: 0.045 tpy of NOx per producing natural gas or coalbed 

natural gas well, equivalent to well emission rates calculated for the Jonah Infill Project, 2004; and 0.3 tpy NOx per producing oil 

well, obtained from Denise Kohtala, WDEQ-AQD, 2003. 

3

 RFD defined as authorized NEPA projects and NEPA projects not yet authorized but for which air emissions have been 

quantified. 

The data in Table A19-12 indicate that permitted sources from January 1, 2001, through June 30, 2003, 

have contributed to additional NOx emissions of 583 tons per year, and other pollutants were reduced in 

emissions for the planning area. Further, the oil and gas commission data indicate that an incremental 

amount of 2 tons per year for NOx should be added. 

A19-26 Pinedale RMP 
Final EIS Appendix 19 

CONCLUSIONS AND RECOMMENDATIONS

A qualitative emission comparison approach was selected for analysis of impacts on air quality. This 

approach was used because (1) sufficient specific data were not available on future projects, (2) 

quantitative analysis will be required as development projects are defined in the future, and (3) WDEQAQD will require demonstration of compliance with federal and state air quality regulations and standards 

for any future development projects. Given the uncertainties regarding the number, nature, and specific 

location of future emission sources and activities, the emission comparison approach is defensible and 

provides a sound basis to compare the potential impacts under the various alternatives. FLMs will require 

a demonstration that potential impacts from proposed projects will not adversely affect AQRVs 

(including visibility) in PSD Class I and sensitive Class II areas. 

For the RMP specific air quality analysis, BLM concludes the following: 

Under Alternative 1, emissions have been calculated for the base year, 10-year, and 20-year time 

horizons. These will serve as the basis for comparison of alternatives. Information in Tables A19-10 and 

A19-11 indicates that the total emissions of criteria pollutants increase from 33,777 tons per year in the 

base year (2001) to 117,622 tons per year by 2021. Most of the increase is the result of oil and gas 

exploration and development. Alternative 2 produces higher emissions than Alternative 1 (emissions of 

124,360 tons per year in 2021), and Alternative 3 produces lower emissions estimates for 2021 (98,831 

tons per year). Alternative 4 produces emissions that are between those of Alternatives 2 and 3 (121,553 

tons per year). 

Given the low ambient concentrations that exist in the planning area for all of the pollutants except O3, it 

is expected that, for any alternative, the increase in emissions of CO, NO2, SO2, PM10, and PM2.5 will not 

cause any exceedance of state or federal ambient air quality standards. Because a quantitative relationship 

between the expected air emissions calculated above and the subsequent potential impacts on ambient 

criteria pollutant concentrations, visibility, atmospheric deposition, or ozone are not known, it is not 

possible to draw any conclusions regarding potential impacts on these air quality values from any 

alternative. BLM intends to make quantitative estimates of these impacts for project-specific EISs and in 

the statewide air quality analysis. 

For the cumulative analysis, BLM concludes the following: 

Given the low ambient concentrations that exist in the planning area for criteria pollutants except O3, it is 

expected that the cumulative increase in emissions for sources in the region of influence (ROI) of CO, 

NOx, SO2, PM10, and PM2.5 would not cause any exceedance of state or federal ambient air quality 

standards. Because a quantitative relationship between the expected air emissions calculated above and 

the subsequent potential cumulative impacts on the air quality values of visibility, atmospheric deposition, 

or ozone are not known, it is not possible to quantify potential impacts on these air quality values from 

the sources in the ROI. However, because air quality analyses from recent energy development projects, 

such as the Pinedale Anticline EIS (2007), estimate potential impacts on visibility, emissions described in 

Section 4.2 may contribute to significant impacts on visibility. 

INTERNET RESOURCES

To develop the data used in this document, a number of Internet resources were accessed. Key 

information concerning emission factors and emissions was obtained from the EPA websites. 

Pinedale RMP A19-27 
Appendix 19 Final EIS 

Climate 

• Western Regional Climate Center: http://www.wrcc.sage.dri.edu/climsum.html/

• NOAA: http://www.noaa.gov

• Stagnation Index: http://www.ncdc.noaa.gov/oa/climate/research/stagnation/stagnation.html

Air Quality: Emissions 

• EPA: http://www.epa.gov/ttn/chief/ap42

Air Quality: Concentrations 

• EPA: http://www.epa.gov/air/data/geosel.html

• CASTNet: EPA: http://www.epa.gov/castnet

• NPS: http://www2.nature.nps.gov/ard/gas/airatlas-du/viewer_index.htm

• BLM: http://www.blm.gov

• BLM: http://www.wy.blm.gov

Air Quality: Atmospheric Deposition 

• NADP: http://nadp.sws.uiuc.edu/

• CASTNet: EPA: http://www.epa.gov/castnet

• NPS: http://www2.nature.nps.gov/ard/gas/airatlas-du/viewer_index.htm

• WARMS (Wyoming Air Resource Monitoring System): http://12.45.109.13/

Air Quality: Visibility 

• IMPROVE: http://vista.cira.colostate.edu/improve

• IMPROVE: http://vista.cira.colostate.edu/views

• FLAG: http://www.WDEQ-AQD.nps.gov/ard/flagfree

• Wyoming Visibility Monitoring Network: http://www.wyvisnet.com 

MITIGATION OPTIONS

Mitigation may be applied to fugitive dust and NOx impacts. Fugitive dust refers to any particulate matter 

that is not deliberately emitted by a well-defined source. Fugitive dust sources typically include 

windblown dust from unvegetated lands, construction, and unpaved roads. Table A19-14 shows several 

available fugitive dust mitigation options. 

Table A19-14. Effectiveness and Costs of Fugitive Dust Mitigation Measures (PM10) 

Dust Sources 

Disturbed 

Areas Unpaved Roads 

Effectiveness 

Level 

proportional to 

percentage of 

land cover 

0–50% 

reduction in 

uncontrolled 

dust emissions 

33–100% 

control 

efficiency 

80% for 15 

mph 

65% for 20 

mph3

25% for 30 

mph3

30% 

reduction 

90% 

reduction 

A19-28 Pinedale RMP 
Final EIS Appendix 19 

Pinedale RMP A19-29 

Dust Sources 

Disturbed 

Areas Unpaved Roads 

Estimated Cost Unknown $4,000/mile 

$2,000 to 

$4,000/mile 

per year 

Unknown $9,000/mile 

$11,000 to 

$60,000/mil

e 

NOx emissions are associated with combustion. Table A19-15 shows several potential mitigation 

measures that could reduce impacts from NOx emissions. The appropriate level of control will be 

determined by the WDEQ-AQD during the construction permit process. 

Table A19-15. Efficiency of Nitrogen Oxides (NOx) Mitigation Measures 

NOx Emissions Sources 

Field 

Compressors 

Sales 

Compressors 

Temporary 

Diesel 

Generators1

Heavy 

Equipment 

Mitigation 

Options/Efficiency 

Implement BACT 

Typically results in a 

NOx emission rate of 

about 1 g/bhp-hr 

Implement BACT 

Typically results in a 

NOx emission rate of 

about 1 g/bhp-hr 

Register with state; 

WDEQ regulate as 

appropriate 

Voluntary use of 

diesel engines 

1

Wyoming is currently registering these generators to determine whether NOx emissions are significant. 

In addition, Table A19-16 shows additional mitigation measures to be considered in the planning area 

impact assessment. These are general mitigation opportunities that should be considered and applied as 

appropriate. BLM has no authority to require any application of these measures, although industry is 

encouraged to implement these measures on its own before they are required by WDEQ. Advances in 

technology are likely to offer new mitigation options during the time covered by the RMP. Under NEPA, 

the planners of individual projects in the planning area must recommend mitigation measures that are 

appropriate for the projects. The WDEQ, as the permitting authority, will review permit applications and 

require specific emission control devices and measures. All costs shown in this table are approximate. 

Table A19-16. Additional Mitigation Measures with Approximate Costs and Benefits 

Type of 

Mitigation Approximate Cost Environmental Cost 

Potential 

Limitations 

Environmental 

Benefit 

Selective Catalytic 

Reduction for 

Compressor 

Emissions 

$4,000 to $27,000 

per NOx ton-year. 

Possible NH3

releases. 

May be cost 

prohibitive for 

oil and gas 

applications. 

NOx emission rate 

reduced to 0.1 g/hp-hr; 

decreased visibility 

impact. 

“Green 

Completions” and 

Flowback Units 

Capital cost ranges 

from $1,000 to 

$10,000. 

Operating cost is 

$1,000/year. 

Payback 1–3 years. 

Moving equipment to 

and from well 

completions. 

Fugitive dust from 

trucks. 

Saves 100,000 cubic 

feet of gas per well per 

year. 

Reduces flaring 

emissions by 70–90% 

at completion. 

Condenser on 

Glycol Dehydrator $1,000 to $10,000. Unknown. 95% VOC and HAP 

reduction. 
Appendix 19 Final EIS 

A19-30 Pinedale RMP 

Type of 

Mitigation Approximate Cost Environmental Cost 

Potential 

Limitations 

Environmental 

Benefit 

Activated Carbon 

Filter on 

Condensate 

Storage Tank 

$1,000 and up Energy required to 

recycle filter. 

50–80% VOC 

reduction. 

Electrical 

Compressors 

Capital cost is 40% of 

gas turbine cost. 

Operating costs 

depend on location of 

transmission lines. 

Displaced air 

emissions from 

compressor unit to 

electric power plant. 

Moving air emissions 

away from sensitive 

PSD Class I areas. 

Fugitive Dust Road 

Treatment 

$2,400–$50,000 per 

mile. 

Possible vegetation 

effects. 20–100% dust control. 

Fugitive Dust 

Administrative 

Control 

$13,000 per well for 

remote telemetry. A 

few added work 

hours per year 

traveling at enforced 

speed limits. 

Minor/unknown. Difficult to 

enforce. 

Reduced vehicle miles 

traveled (VMT) with 

related emission 

reductions. Slower 

speeds give 20–50% 

reductions in dust 

emissions. 

Larger Diameter 

Sales Pipeline 

Capital costs 

increase with larger 

pipes. Operating 

costs decrease with 

larger pipes. 

Larger trench for 

burying line. Slightly 

more surface 

disturbance. 

Probably 

applicable only 

for large 

producing 

operations. 

Possibly resulting in 

lower compressor 

emissions. 

Microhole Drilling 

Cost of technology 

transfer; then 

potentially less than 

conventional drilling. 

Additional impacts if 

duplicate drilling is 

necessary. 

Lighter equipment on 

roads, smaller drilling 

sites, reduced gaseous 

emissions during 

drilling. 

Condensate 

Pipelines 

Cost of pipe and 

installation minus 

cost of eliminated 

storage tank and 

trucking. 

Trench for burying 

line. 

The cost may 

outweigh 

benefit. 

Eliminate emissions 

from storage vessels; 

eliminate miles 

traveled by vacuum 

trucks. 

Stage I Vapor 

Controls for 

Condensate 

Transfer for Truck 

Loading 

$1,000–$3,000 Potential fire risk with 

improper operation. 

90% VOC emission 

reduction during 

transfer. 

Wind Farm Electric 

Generation 

4 to 5 cents/kW-hr. 

Capital costs are 

large. 

Visual impacts, 

impacts on raptors, 

maintenance. 

Large capital 

costs required 

Reduced power plant 

emissions. (VOC, NOx, 

SO2, CO, CO2) 

Phased Oil and 

Gas Development 

Short-term loss of 

state and federal 

royalties 

Emissions averaged 

over a longer period. 

Peak emissions and 

impacts are reduced.