Western Energy Company Federal Coal Lease Modification MTM 80697 Environmental Assessment

U.S. Department of the Interior Bureau of Land Management Miles City Field Office

Environmental Assessment DOI-BLM-MT-C020-2016-0115-EA October 2018 Western Energy Company Federal Coal Lease Modification MTM 80697 Environmental Assessment

Location: Rosebud County, Montana Applicant/Address: Western Energy Company 138 Rosebud Lane PO Box 99 Colstrip, MT 59323 Phone: (406) 748-5100

U.S. Department of the Interior Bureau of Land Management Miles City Field Office 111 Garryowen Road Miles City, MT 59301 Phone: (406) 233-2800 Fax: (406) 233-2921

TABLE OF CONTENTS

Chapter 1 Purpose and Need ...... 1 1.1 Proposed Action & Background ...... 1

1.1.1 Existing Rosebud Mine & Federal Coal Lease ...... 1 1.1.2 Proposed Lease Modification ...... 3 1.2 Purpose and Need ...... 3 1.3 Decision to be Made ...... 4 1.4 Conformance with Land Use Plan ...... 4

1.4.1 Coal Screens ...... 5 1.5 Relationship to Statutes, Regulations, Other NEPA Documents ...... 6

1.5.1 Statutes and Regulations Administered by Other Agencies ...... 6 1.5.2 Previous NEPA Analyses ...... 7 1.6 Public Involvement, Consultation and Coordination ...... 7

1.6.1 Scoping ...... 7 1.6.2 Public Comments ...... 8 1.6.3 Consultation and Coordination ...... 8 1.6.4 Resource Issues Identified for Analysis ...... 8 1.7 Resource Issues Eliminated from Further Analysis ...... 9

Chapter 2 Proposed Action and Alternatives ...... 10 2.1 Introduction ...... 10 2.2 Alternatives Considered, but Eliminated ...... 10 2.3 Alternative A – Proposed Action ...... 10

2.3.1 Lease Modification ...... 10 2.3.2 Foreseeable Mining Activities ...... 10 2.4 Alternative B – No Action Alternative ...... 15

Chapter 3 Affected Environment and Environmental Consequences ...... 16 3.1 Introduction ...... 16 3.2 General Setting ...... 17 3.3 Past, Present, and Reasonably Foreseeable Actions ...... 17 3.4 Resource Issue 1 - Wildlife ...... 20

3.4.1 Affected Environment ...... 20 3.4.2 Environmental Impacts – Alternative A (Proposed Action) ...... 21 3.4.3 Environmental Impacts – Alternative B (No Action) ...... 21 3.4.4 Mitigation and Residual Effects ...... 22 3.4.5 Cumulative Impacts ...... 22 3.5 Resource Issue 2 - Air Quality ...... 23

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3.5.1 Affected Environment ...... 23 3.5.2 Environmental Impacts – Alternative A (Proposed Action) ...... 25 3.5.3 Environmental Impacts – Alternative B (No Action) ...... 30 3.5.4 Mitigation and Residual Effects ...... 31 3.5.5 Cumulative Effects ...... 31 3.6 Resource Issue 3 - Climate...... 34

3.6.1 Affected Environment ...... 35 3.6.2 Environmental Impacts – Alternative A (Proposed Action) ...... 35 3.6.3 Environmental Impacts – Alternative B (No Action) ...... 37 3.6.4 Mitigation and Residual Effects ...... 37 3.6.5 Cumulative Effects ...... 37 3.7 Resource Issue 4 - Noise ...... 39

3.7.1 Affected Environment ...... 39 3.7.2 Environmental Impacts – Alternative A (Proposed Action) ...... 39 3.7.3 Environmental Impacts – Alternative B (No Action) ...... 40 3.7.4 Mitigation and Residual Effects ...... 41 3.7.5 Cumulative Impacts ...... 41 3.8 Resource Issue 5 - Waste and Pollution ...... 41

3.8.1 Affected Environment ...... 41 3.8.2 Environmental Impacts – Alternative A (Proposed Action) ...... 42 3.8.3 Environmental Impacts – Alternative B (No Action) ...... 43 3.8.4 Mitigation and Residual Effects ...... 43 3.8.5 Cumulative Impacts ...... 43

List of Preparers ...... 45 References ...... 46

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LIST OF TABLES Table 1. Tons of Coal that could be Permitted and Mined in Association with the Proposed Action...... 14

Table 2. Estimated Criteria Air Pollutant Emissions Associated with Coal Production Under the Proposed Action, tons/year ...... 26

Table 3. Trace Metal Hazardous Air Pollutant Emissions from Fugitive Coal Dust Associated with Coal Production Under the Proposed Action1...... 27

Table 4. Diesel Particulate Matter Emissions Associated with Coal Production Under the Proposed Action ...... 27

Table 5. Global Warming Potential of Greenhouse Gasses as Carbon Dioxide Equivalents ...... 35

Table 6. Estimated Maximum Annual Greenhouse Gas Emissions Associated with the Proposed Action 36

Table 7. Comparisons with Montana, US and Global Annual Greenhouse Gas Emissions Totals ...... 36

Table 8. Estimated Total Greenhouse Gas Emissions Associated with the Proposed Action ...... 37

Table 9. Greenhouse Gas Emission Comparisons ...... 38

Table 10. Greenhouse Gas Emission Comparisons in terms of Greenhouse Gas Equivalency ...... 38

Table 11. BLM staff...... 45

Table 12. NEPA contractors...... 45

LIST OF FIGURES Figure 1. Project Location ...... 2 Figure 2. Existing Condition and Permitted Activity...... 11 Figure 3. Reasonably Foreseeable Activity Associated with the Proposed Action...... 12 Figure 4. Reasonably Foreseeable Development of Area B AM5 ...... 19

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Acronyms and Abbreviations Acronym or Abbreviation Definition Δdv change in deciviews μm micrometers µg/m3 micrograms per cubic meter AQRVs air-quality related values, ARM Annotated Rules of Montana ARMP Approved Resource Management Plan BLM Bureau of Land Management CAPs criteria air pollutants CASTNET Clean Air Status and Trends Network CCR coal combustion residuals CEQ Council on Environmental Quality CERP Contingency and Emergency Response Plan CH4 methane CO carbon monoxide

CO2 carbon dioxide

CO2e CO2 equivalents DEIS Draft Environmental Impact Statement DPM diesel particulate matter EA Environmental Assessment EIS Environmental Impact Statement EPA Environmental Protection Agency FCLAA Federal Coal Leasing Act Amendment (1976) FLPMA Federal Land Policy and Management Act g/ha grams per hectare GHG Greenhouse gas GHGRP Greenhouse Gas Reporting Program GWP global warming potential HAPs Hazardous Air Pollutants IMPROVE Interagency Monitoring of Protected Visual Environments IPCC Intergovernmental Panel on Climate Change kg/ha kilograms per hectare LM Lease Modification LMA Lease Modification Application MAAQS Montana Ambient Air Quality Standards MAQP Montana Air Quality Permit MCFO Miles City Field Office MDEQ Montana Department of Environmental Quality MDN Mercury Deposition Network MDSL Montana Department of State Lands MEPA Montana Environmental Policy Act mg/ha milligrams per hectare MLA Mineral Leasing Act (1920)

October 2018 iv Acronyms and Abbreviations

Acronym or Abbreviation Definition Mn manganese MSUMRA Montana Strip and Underground Mine Reclamation Act MT Montana Mt Million tons Mtpy Million tons per year NAAQS National Ambient Air Quality Standards NADP National Atmospheric Deposition Program NEPA National Environmental Policy Act NHPA National Historic Preservation Act

NO2 nitrogen dioxide N2O nitrous oxide NTN National Trends Network

O3 ozone OSMRE Office of Surface Mining Reclamation and Enforcement Pb lead

PM10 particulate matter with a nominal diameter of 10 microns or less PM2.5 particulate matter with a nominal diameter of 2.5 microns or less ppb parts per billion ppm parts per million PRMP Proposed Resource Management Plan RCRA Resource Conservation Recovery Plan RMP Resource Management Plan SHPO State Historic Preservation Office SHWMP Solid and Hazardous Waste Management Plan SMCRA Surface Mine Control and Reclamation Act of 1977

SO2 sulfur dioxide SPCCMP Spill Prevention Control and Counter Measures Plan THPO Tribal Historic Preservation Office US United States USC United States Code US DOI United States Department of Interior VOCs volatile organic compounds WECo Western Energy Company WY Wyoming

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CHAPTER 1 PURPOSE AND NEED

1.1 Proposed Action & Background

This Environmental Assessment (EA) has been prepared to analyze and disclose the potential environmental effects of modifying Federal Coal Lease MTM 80697; herein referred to as the Proposed Action. Federal coal resources affected by the Proposed Action are managed by the United States Department of Interior (US DOI) Bureau of Land Management (BLM) Miles City Field Office (MCFO).

BLM is required to analyze the environmental effects of modifying the lease in order to comply with the National Environmental Policy Act of 1969 (NEPA [42 United States Code (USC) §4321 et seq.]) per 43 Code of Federal Regulations (CFR) 3432.3c. This EA is a site-specific analysis of potential impacts from the implementation of the Proposed Action (lease modification) and the No Action Alternative. The EA is written to comply with NEPA and assist in making a determination as to whether any significant impacts would result. Significance is defined by the Council on Environmental Quality (CEQ) regulations for implementing NEPA found in 40 CFR § 1508.27. An EA provides evidence for determining whether to prepare an Environmental Impact Statement (EIS) or a Finding of No Significant Impact (FONSI) and potential BLM Decision Record. The BLM will evaluate the impacts and public comments and make its decision.

Potential effects associated with the nearby proposed mine permit known as Area F at the Rosebud Mine were recently analyzed and described in the Area F Draft EIS (hereafter “Area F DEIS”, OSMRE & MDEQ 2018). The background information and impact assessment presented in the Area F DEIS are germane to the description of the Proposed Action and No Action Alternative and their environmental effects; therefore, the Area F DEIS is incorporated by reference into this analysis.

1.1.1 Existing Rosebud Mine & Federal Coal Lease

The applicant for the lease modification, Western Energy Company (WECo), currently operates the Rosebud Mine (hereafter “Mine”) located near Colstrip, in Rosebud County, Montana (Figure 1). The Mine is a surface coal mine composed of five surface mine permits encompassing over 25,000 acres and approved by the Montana Department of Environmental Quality (MDEQ) in accordance with the Montana Surface and Underground Mine Reclamation Act (MSUMRA) and Surface Mine Control and Reclamation Act of 1977 (SMCRA). The Mine annually produces 8.0 to 10.25 million tons (Mt) of low-sulfur subbituminous coal transported to the Colstrip Steam Electric Station (hereafter “Colstrip Power Plant”) and Rosebud Power Plant and combusted for power generation (Area F DEIS Section 1.1).

WECo’s existing MSUMRA mine permits (hereafter “mine permit” or “mine permits”) describe baseline environmental conditions, mineral and surface ownership, mining and reclamation methods, plans for protection of the hydrologic balance, environmental monitoring and mitigation measures, bonding requirements, and related conditions with reference to the regulatory requirements specified by MSUMRA and attendant regulations. The Area B (SMP C1984003B; WECo 2018a) and Area C (SMP C1985003C; WECo 2018b) mine permits are incorporated by reference into this analysis.

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Figure 1. Project Location

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WECo occasionally proposes mine permit revisions (changes to the mining or reclamation plan within a mine permit boundary), mine permit amendments (changes to the mine or reclamation plan that result in expansion or decrease of the operation's permitted boundaries, excluding incidental boundary changes), or new mine permits (e.g., Area F) as needed to increase reserves available for future mining.1 Prior to obtaining MDEQ’s approval of mine permitting actions under MSUMRA, WECo must obtain surface and mineral lease agreements as necessary to allow proposed mining operations.

WECo operates a portion of the Mine under Federal coal lease MTM 80697 which includes approximately 1,431 acres of Federal coal mineral estate located within the Mine’s Area B (WECo 2018a) and Area C (WECo 2018b) mine permit boundaries and permitted mining area. Mining began in the Mine Area B in 1976 and in Area C in 1983 and has progressed to a point where mine passes are near the boundary of unleased Federal coal tracts subject to the Proposed Action. A portion of the privately-owned surface overlying the unleased Federal coal has been disturbed in association with permitted mining. Additional disturbance of the overlying surface is permitted to occur as mining of adjacent leased Federal and private coal resources and associated reclamation advances.

1.1.2 Proposed Lease Modification

On November 1, 2013, BLM received a Lease Modification Application (LMA) to Federal coal lease MTM 80697, which was filed under the lease by modification regulations at 43 CFR Part 3432 and the provisions of the Energy Policy Act of 2005. WECo submitted the LMA to increase mineable coal reserves in the Area B and Area C permits by adding currently unleased Federal coal that lies adjacent to existing private and Federal coal leases and directly in advance of existing adjacent mining activities.

The proposed lease modification tracts (LM Tracts) include approximately 160 acres of Federal coal reserves with the legal descriptions listed below:

Montana Principal Meridian, Rosebud County, Montana

T. 1 N., R. 40 E.,

sec. 6: S½SW¼, S½SW¼SE¼, 100 acres, more or less (hereafter the “Area C LM Tract”)

sec. 14: SE¼SE¼, S½NE¼SE¼, 60 acres, more or less (hereafter the “Area B LM Tract”)

1.2 Purpose and Need

The purpose and need for the BLM is to respond to the proposed LMA to modify Federal coal lease MTM 80697 by including the 160 acres included in the LM Tracts identified above. This action is needed for BLM to respond to WECo’s LMA, which would lead to further permitting and mining of Federal coal in the LM Tracts and facilitate mining of adjacent otherwise uneconomical Federal and private coal. The

1 See ARM 17.24.301 for definitions of “Amendment”, “Minor Revision”, “Major Revision”, and “Incidental Boundary Revisions” under MSUMRA.

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action also satisfies BLM’s requirement to consider leasing Federally-owned minerals under the Mineral Leasing Act (MLA) of 1920, as amended by the Federal Coal Leasing Act (Amendment; FCLAA) of 1976, and provisions of the Energy Policy Act of 2005.

1.3 Decision to be Made

The decision to be made is whether or not to lease the Federal coal resources contained in the LMA for MTM 80697 and, if so, under what terms, conditions, and stipulations pursuant to 43 CFR Part 3432. A decision to modify Federal coal lease MTM 80697 to include the LM Tracts would be a prerequisite for mining, but a BLM coal lease does not authorize mining operations.

1.4 Conformance with Land Use Plan

The Proposed Action is in accordance with decisions contained in the 2015 MCFO Approved Resource Management Plan (hereafter “MCFO ARMP”, BLM 2015a and 2015b) including provisions for the development of mineral resources in an environmentally responsible manner. The 2015 MCFO ARMP replaces the land use plan decisions in the Powder River Resource Area Resource Management Plan (hereafter “Powder River RMP”), (BLM 1984 and 1985) for the planning area.

Specific management direction for mineral resource development provided within the MCFO ARMP includes: • MD MIN 1: Areas identified in the Big Dry and Powder River RMPs (BLM 1996 and 1985) as acceptable for further consideration for coal leasing are carried forward. • MD MIN 2: All coal leasing and coal exchange proposals will be evaluated for their suitability for leasing or exchange. • MD MIN 3: At the time an application for a new coal lease or lease modification is submitted to the BLM, the BLM will determine whether the lease application area is “unsuitable” for all or certain coal mining methods pursuant to 43 CFR § 3461.5. Priority Habitat Management Areas are essential habitat for maintaining greater sage-grouse for purposes of the suitability criteria set forth at 43 CFR § 3461.5(o)(1).

Under the U.S. Montana District Court case Western Organization of Resource Councils (WORC), et, al. vs BLM; CV 16-21-GF-BMM, WORC and other plaintiffs argued that BLM failed to meet NEPA when preparing and issuing the ROD for the MCFO and Buffalo ARMPs (2015). The US District Court in Great Falls, Montana issued an opinion and amended order on March 26, 2018 and another order on July 31, 2018. The March 26, 2018, Order concluded: 1) NEPA requires BLM to conduct new coal screening and consider climate change impacts to make a reasoned decision on the amount of recoverable coal available in the ARMP, 2) BLM must supplement the Miles City Final Environmental Impact Statement with an analysis of the environmental consequences of downstream combustion of coal, oil, and gas open to development under the ARMP, and 3) BLM must provide additional justification and analysis of global warming potential (GWP) over an appropriate planning period consistent with evolving science. The Orders did not vacate the ROD and did not enjoin leasing as long as the NEPA prepared for leasing applications undergo comprehensive environmental analyses in compliance with the District Court’s March 26, 2018 order and all existing procedural requirements under NEPA and the APA. The BLM has addressed these issues from the litigation in several sections of the EA: coal screens are addressed in Section 1.4.1

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and greenhouse gasses (including global warming potentials) and climate change (including downstream combustion) analyses are addressed in Section 3.6.

1.4.1 Coal Screens

The FCLAA requires that lands considered for leasing be included in a comprehensive land use plan and that leases be compatible with that plan. BLM uses four screens designed to identify coal deposits and limit the coal found acceptable for further consideration to those areas with the best coal potential and where no overriding resource or environmental conflicts exist. The screens were applied during development of the Powder River RMP (BLM 1983, 1984, 1985). The 1985 decisions were carried forward (adopted) in the MCFO ARMP (BLM 2015a and 2015b), which also stated that the unsuitability screen would be re-applied in response to individual coal lease applications.

1.4.1.1 Review of Coal Screens from Land Use Planning

The first screen requires that coal tracts have development potential. The LM Tracts are within an area identified as having moderate-high coal development potential (BLM 1983), which is reaffirmed and supported by WECo’s mining plans as presented in the LMA (WECo 2013). The second screen considers unsuitability and is discussed in Section 1.4.1.2. The third screen considers eliminating lands due to multiple use conflicts beyond those identified under the unsuitability screen. Since BLM only has jurisdiction over the mineral estate on the LM tracts and regulations (43 CFR 3400.1) address multiple use of minerals, there are no conflicts under this screen. The fourth screen requires consultation with qualified surface owners to obtain their views on surface mining. The LM tracts did not receive negative views from surface owners (BLM 1983), and were made available for leasing (BLM 1985, 2015a, and 2015c). The current surface owners have agreements with the Mine and are not qualified surface owners under this screen (WECo 2013, Exhibit 4).

1.4.1.2 Application of Unsuitability Criteria

The unsuitability criteria in 43 CFR Part 3461.5 provide that coal lands shall be considered unsuitable for all or certain stipulated methods of coal mining if they fall within any of 20 criteria. During development of the Powder River RMP, all 1,123,600 acres of Federal coal with development potential in the MCFO planning area were assessed relative to the unsuitability criteria (BLM 1983, 1984, and 1985). The LM Tracts were found suitable for further consideration in leasing.

The unsuitability criteria were reapplied to the LM Tracts for this analysis and found suitable for all criterion except Criterion 15. Several active sharp-tailed grouse leks occur within 2 miles of the LM Tracts and are therefore designated unsuitable under Criterion 15. However, impacts to sharp-tailed grouse habitats surrounding leks are mitigatable and “a lease may be issued if, after consultation with the State, the surface management agency determines that all or certain stipulated methods of coal mining will not have a significant long-term impact on the species being protected” [43 CFR § 3461.5(o)(1)]. Montana Fish, Wildlife and Parks (MFWP), after consultation, agrees mitigation identified in Section 3.6.5 would be adequate to prevent significant long-term impacts to sharp-tailed grouse. Therefore, the LM Tracts are considered suitable for leasing with stipulation to protect sharp-tailed grouse.

Complete review of the unsuitability criterion is provided in the administrative record.

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1.5 Relationship to Statutes, Regulations, Other NEPA Documents

WECo’s LMA was submitted and will be processed and evaluated under the following Federal authorities: • Mineral Leasing Act of 1920 (MLA), as amended; • Multiple-Use Sustained Yield Act of 1960; • National Environmental Policy Act of 1969 (NEPA); • Federal Coal Leasing Act Amendment of 1976 (FCLAA); • Federal Land Policy Management Act of 1976 (FLPMA); • Surface Mining Control and Reclamation Act of 1977 (SMCRA); and • Energy Policy Act of 2005.

The BLM, charged with administration of the mineral estate of these Federal lands, is required by law to consider leasing Federally-owned minerals for economic recovery. The FLPMA states that public lands shall be managed in a manner that recognizes the nation’s need for domestic sources of minerals [43 USC 1701(a)(12)]. The BLM regulates coal mining operations to ensure that maximum economic recovery of the coal resource is achieved (43 CFR 3480), while maintaining compliance with other applicable laws and regulations. BLM is the agency responsible for leasing Federal coal lands under the MLA [30 USC §181 et seq.]), as amended by the FCLAA (30 USC §1272 et seq.) and is the lead agency in preparing this EA.

1.5.1 Statutes and Regulations Administered by Other Agencies

SMCRA gives the Office of Surface Mining, Reclamation, and Enforcement (OSMRE) primary responsibility to administer programs that regulate surface coal mining operations in the US. Pursuant to Section 503 of SMCRA, MDEQ developed, and the Secretary of the Interior approved, Montana’s permanent regulatory program authorizing MDEQ to regulate surface coal mining operations (and surface effects of underground coal mining) on private and state lands in Montana, and in April 1981, MDEQ entered into a cooperative agreement with the Secretary of the Interior authorizing MDEQ to regulate surface coal mining operations (as well as the surface effects of underground coal mining) on Federal lands within Montana (per Section 523(c) of SMCRA). Mining and reclamation methods specified in mine permits are required to be consistent with MSMURA and SMCRA (30 USC, Chapter 25) and the implementing state regulations [Annotated Rules of Montana (ARM) 17.24.301-1309] and Federal regulations (30 CFR Chapter VII).

If Federal coal lease MTM 80697 is modified to include the proposed 160-acre LM Tracts, prior to mining the LM Tracts WECo would be required to apply to MDEQ to revise or amend an existing mine permit or propose a new permit. Subsequent to receiving MDEQ’s approval for a proposed mine permit action, and prior to removing coal from the LM Tracts, OSMRE would determine whether the permitting action constitutes a mining plan modification under 30 CFR § 746.18. If the action constitutes a mining plan modification, OSMRE would evaluate the proposed mining as required by 30 CFR Part 746 to make a recommendation to the Secretary of the Interior regarding whether the proposed mining plan modification should be approved, disapproved, or approved with conditions. Mining and other foreseeable activities associated with the Proposed Action would also be subject to state laws and permits pertaining to water quality and air quality.

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In accordance with the CEQ [40 CFR 1501.6 et seq.], opportunity was provided for MDEQ and OSMRE to serve as cooperating agencies for the preparation of this EA given these agencies have jurisdiction by law as well as special expertise. Both agencies declined the opportunity to be a cooperator on this project.

1.5.2 Previous NEPA Analyses

The effects of mining the existing Federal coal lease and LM Tracts were previously analyzed by the Western Energy Coal Lease Application (MTM-80697) EIS (BLM 1994), but the LM Tracts were not leased by WECo at that time. The LM Tracts are also located within an area that has been evaluated within several regional NEPA documents, including the recently prepared Area F DEIS, the 2015 MCFO Proposed Resource Management Plan and Final EIS (PRMP) (BLM 2015c), the 1984 Powder River RMP (BLM 1984 and 1985), and an EIS jointly prepared by Montana Department of State Lands (MDSL) and OSMRE to evaluate environmental effects of mining at the Mine (MDSL and OSMRE 1983). In addition, multiple proposed mining actions in Area B and Area C of the Mine have been analyzed by MDEQ and MDSL in accordance with the Montana Environmental Policy Act (MEPA).

Cumulative analysis of climate resources presented in an EA prepared for the Cedar Creek Anticline CO2 Pipeline and EOR Development Projects (BLM 2018a), hereafter the “Denbury EA”, discusses greenhouse gas (GHG) emissions from within the MCFO planning area, including the Mine (see BLM 2018a, Chapter 3 Resource Issue 1 and Appendix D).

This EA summarizes, incorporates by reference, and ties to information and analyses presented in these and other existing documents, as appropriate.

1.6 Public Involvement, Consultation and Coordination

1.6.1 Scoping

BLM conducted two scoping periods (2014 and 2016) to obtain comments and information from the public. Internal scoping and public scoping comments were used to identify issues to be analyzed in the EA and identify resources and issues that should be dismissed from analysis.

The first public scoping period occurred between September 5 and October 10, 2014. A public scoping meeting was held in Colstrip, Montana on September 25, 2014, and a notice of this meeting was published in the Miles City Star on September 9, 2014. Meeting notices were also mailed out to a compiled list of potentially interested agencies, individuals, organizations, and businesses.

Following a 2-year delay on the Project, the BLM opened another 30-day scoping period from October 31 through November 30, 2016. BLM notified the public by issuing a press release, posting a notice on the BLM Montana/Dakota’s website and E-planning, and sending the announcement to the same 2014 list of interested agencies, individuals, organizations, and businesses.

Notice of this project has been posted in the NEPA Register on the BLM’s ePlanning website since 2016: https://eplanning.blm.gov/epl-front-office/eplanning/lup/lup_register.do

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1.6.2 Public Comments

Scoping letters were received from 144 individuals and representatives of private and public entities during the 2014 and 2016 public scoping period, combined. No one from the public attended the public scoping meeting held in Colstrip on September 25, 2014, and no verbal or written comments were submitted at the meeting. A majority of the written comments received directly by the BLM (141) were attributed to an organized form-letter campaign. The remaining comments (3) represent unique responses, generated individually by organized groups with an interest in the proposed project. A description of issues analyzed in this EA are summarized in Section 1.6.4. Additional details regarding the scoping processes and results are presented in the scoping report prepared by BLM (2018b).

1.6.3 Consultation and Coordination

The BLM consults with Native Americans under various statutes, regulations, and executive orders, including the American Indian Religious Freedom Act, the National Historic Preservation Act (NHPA), the Native American Graves Protection and Repatriation Act, NEPA, and Executive Order 13175 - Consultation and Coordination with Indian Tribal Governments. BLM notified the Tribal chairmen and Tribal Historic Preservation Officers (THPOs) by letter during the 2014 and 2016 public scoping periods. No Tribal chairmen or THPOs responded to requests for consultation.

A full list of Tribes, adjacent land owners, individuals, organizations, and agencies which were consulted during the preparation of this EA is included in the scoping report (BLM 2018b).

The Proposed Action is considered a Federal undertaking, as defined in Section 106 of NHPA and its implementing regulations found in 36 CFR 800. The BLM’s Cultural Resource Program in Montana operates under a National Programmatic Agreement with an implementing protocol with the Montana State Historic Preservation Office (SHPO). The BLM has consulted with the Montana SHPO under provision Section VIII.8D of its state protocol. BLM determined the proposed action would have no effect to historic properties and communicated this to the Montana SHPO on September 18, 2018. The Montana SHPO concurred with BLM’s determination of no effect to historic properties on September 20, 2018.

As noted in Section 1.5.1 above, MDEQ and OSMRE denied BLM’s request to be cooperators on this project.

BLM coordinated with MFWP during reapplication of the unsuitability criterion as required by the MCFO ARMP and FCLAA (see Section 1.4.1.2).

1.6.4 Resource Issues Identified for Analysis

An issue is a point of disagreement, debate, or dispute with a proposed action based on some anticipated environmental effect. CEQ regulations at 40 CFR § 1500.4 and 1501.7 require an EA to focus on issues that are key to the proposed action. Specific issues pertaining to the LMA are outlined in the scoping report (BLM 2018b) and include the following.

Issue 1 – Wildlife

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• What are the potential impacts to sharp-tailed grouse leks from potential indirect surface disturbing and disruptive activities and mining of the 160 acres of Federal coal and adjacent otherwise uneconomical coal?

Issue 2 - Air Quality

• What are the potential indirect impacts to air resources from the estimated magnitude of criteria air pollutants (CAPs), and hazardous air pollutants (HAPs) from future mining activities of the Federal coal tracts and adjacent otherwise uneconomical coal? • What are the potential indirect impacts to air from dispersion and/or deposition of CAPS or HAPs from combustion or mining emissions for the Federal coal tracts and adjacent otherwise uneconomical coal?

Issue 3 – Climate

• How would mining and combustion of coal contribute to GHGs?

Issue 4 – Noise

• What are the potential indirect impacts to local residents from noise created by surface disturbance and mining on the LM Tracts?

Issue 5 - Waste and Pollution

• Would leasing the proposed tracts generate wastes that would impact the local community and environment?

These issues have been brought forward to be analyzed in the EA and are presented in Chapter 3.

1.7 Resource Issues Eliminated from Further Analysis

During the scoping process, the following resources were determined to not be present within or adjacent to the area that would be affected by the Proposed Action: Native American religious concerns, fisheries, special-status species plants, bighorn sheep, crucial big game winter range, northern long-eared bat, black- tailed prairie dog colonies, bald eagles, and colonial nesting birds.

The BLM determined that the following resources were present within or adjacent to the area of the Proposed Action but not affected to a degree that detailed analysis is required at this time: historic or cultural resources, environmental justice, socioeconomics, aquatics (non-fish), migratory birds, golden eagles, surface water resources.

The scoping report (BLM 2018b) documents the rationale for the resources and issues that are not carried forward. The scoping report is available upon request.

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CHAPTER 2 PROPOSED ACTION AND ALTERNATIVES

2.1 Introduction

This EA analyzes the potential impacts of implementing the Proposed Action and the No Action Alternative. The No Action Alternative is considered and analyzed to provide a baseline against which to compare the effects of the Proposed Action.

2.2 Alternatives Considered, but Eliminated

No reasonable alternatives to the Proposed Action and No Action Alternative were developed as a result of public scoping or BLM’s review of the application.

2.3 Alternative A – Proposed Action

The Proposed Action is to approve the LMA. Mining of the LM Tracts and associated activities are reasonably foreseeable if the LMA is approved. The lease modification and reasonably foreseeable mining of the lease tracts are presented together in this section to provide concise reference for impact analysis in Chapter 3.

2.3.1 Lease Modification

WECo has submitted a LMA for Federal coal lease MTM 80697 (WECo 2013). The LM Tracts encompass 160 acres, collectively, adjacent to existing permitted mining areas in Area B (WECo 2018a) and Area C (WECo 2018b) and entirely within the existing mine permit boundaries (Figure 2). Legal descriptions of the land within the LM Tracts are presented in Section 1.1.2.

2.3.2 Foreseeable Mining Activities

WECo’s objective is to mine portions of the two LM Tracts (WECo 2013 and 2018c). Approval of the lease modification would facilitate extraction of adjacent Federal and private coal that would otherwise be uneconomical to mine and be bypassed (hereafter referred to as “bypass coal”) (Figure 3). The coal would ultimately be transported to the Colstrip Power Plant and Rosebud Power Plant and combusted for power generation. Permitted mine passes (coal removal areas) abut both LM Tracts and a substantial portion of the surface overlying the LM Tracts (88 percent of the Area B LM Tract and 50 percent of the Area C LM Tract) would be disturbed in association with permitted activities (Figure 2) (WECo 2018c, 2018b, 2018c). As noted in Section 1.5.1, additional approval by MDEQ and review by OSMRE would be required prior to mining the LM Tracts if the LMA is approved as proposed. Mining and reclamation described in future mine permit application materials would be specific to the affected areas but methods are not expected to differ substantially from those described in the existing Area B (WECo 2018a) and Area C (WECo 2018b) mine permits as mine activities would be expanded or continue to encompass the additional mining areas.

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Figure 2. Existing Condition and Permitted Activity

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Figure 3. Reasonably Foreseeable Activity Associated with the Proposed Action.

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Expected changes (expansion) to approved mining passes (WECo 2018a, 2018b; Exhibit A in both permits) and attendant coal removal and surface disturbances that could occur subsequent to LMA approval are summarized below.

Mine Permit Area B

Mine Permit Revision – A mine permit revision could allow additional mining within the Area B permit boundary. Six permitted mine passes could be extended eastward and three additional passes could be added to the south of permitted passes (Figure 3) to recover 2.1 Mt of coal, including 1.0 Mt Federal coal in the Area B LM Tract plus 1.1 Mt of bypass coal (Table 1). Mining within the existing permit boundary would not require additional surface disturbance beyond that already permitted to occur.

Mine Permit Amendment – A mine permit amendment could incorporate areas south and east of the Area B LM Tract into the mine permit, expanding mining from what could be allowed by mine permit revision alone (discussed above). An amendment would allow eight passes to be extended eastward and four additional passes south of the three added by revision (Figure 2). This would allow economical mining of the entire Area B LM Tract totaling 2.2 Mt of Federal coal plus 3.3 Mt of bypass coal. Mining the complete Area B LM Tract and adjacent bypass coal would disturb an estimated 119 acres in addition to that currently permitted.

Federal Mining Plan Review – Subsequent to receiving MDEQ approval to include additional mine passes in Federal coal and prior to mining Federal coal in the Area C LM Tract, OSMRE would review the mining plan in accordance with 30 CFR Part 746 as discussed in Section 1.5.1.

Mining Schedule – Based on preliminary mine plan data (WECo 2018c, 2018d), coal removal in the Area B LM Tract and adjacent bypass coal could occur during a 16-year period from 2019 to 2034, although removal is not scheduled from year 4 (2022) to year 12 (2030). This schedule further assumes that mining outside the current permit boundary would be conducted in conjunction with proposed Area B permit amendment AM5 (hereafter “Area B AM5”) discussed further in Section 3.3.

Mine Permit Area C

Existing Permitted Passes – A small portion of the Area C LM Tract is within two permitted mine passes (WECo 2018b, Exhibit A) (Figure 2). Removal of the Federal coal in the LM Tract in these passes (0.1 Mt, Table 1) is contingent upon lease approval and receiving approval of a Federal mining plan modification, if required.

Mine Permit Revision – Seven mining passes would be added south of currently permitted passes to recover coal in the Area C LM Tract and adjacent parcels (Figure 2). Preliminary mine plans (WECo 2018c, 2018d) indicate that economical mining could recover 10.8 Mt of coal in total, comprised of 4.9 Mt of Federal coal in the Area C LM Tract, plus 5.9 Mt of bypass coal (Table 1). The additional mine passes would require an estimated 90 acres of surface disturbance beyond that currently permitted. This mining could be approved as a permit revision without amendment to expand the permit boundary.

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Mining Schedule – Based on preliminary mine plans (WECo 2018c, 2018d), coal removal in the Area C LM Tract and adjacent bypass coal could begin within 5 years (2023) and continue for approximately 3 years (2026). This schedule is contingent on receiving approval of the Federal mining plan modification as discussed in Section 1.5.1.

Table 1. Tons of Coal that could be Permitted and Mined in Association with the Proposed Action. Bypass Bypass Bypass Total Permit & Permitting Action LM Tract Private Federal Sub-Total Coal Area B Permit Revision 1,012,956 263,756 818,339 1,082,096 2,095,051 Amendment 1,187,086 2,099,075 74,993 2,174,068 3,361,154 Area B Total 2,200,041 2,362,831 893,332 3,256,164 5,456,205 Area C Permitted Passes1 127,887 Permit Revision 2,571,157 1,994,381 629,280 2,623,661 5,322,705 Area C Total 2,699,044 1,994,381 629,280 2,623,661 5,322,705 Area B and Area C Total 4,899,085 4,357,212 1,522,612 5,879,825 10,778,910 1) Two mine passes approved in the mine permit encompass a portion of the LM Tract. Mining is contingent on LMA approval, and subsequent OSMRE review.

Based on these preliminary plans (WECo 2018c, 2018d), mining in association with the Proposed Action collectively could extract 10.8 Mt of coal in total; consisting of 4.9 Mt within the LM Tracts plus 5.9 Mt of bypass coal. Approximately 6.4 Mt of Federal coal would be mined in association with the Proposed Action, including 1.5 Mt of Federal bypass coal in the existing lease (MTM 80697). Federal coal underlying 30 acres of the 100-acre Area C LM Tract is not within planned mine passes (Figure 2, WECo 2018c) as it could not be economically mined at this time. Mining and reclamation activities associated with coal removal from the LM Tracts and bypass areas would disturb an estimated 209 acres in addition to that authorized by the existing mine permits.

Depending on the timing of requisite approvals, economically recoverable coal in the LM Tracts and bypass coal could be mined beginning as early as 2019 and conclude in 2034, although mining of these areas would not occur in year 4 (2022) or years 9 through 12 (2027 to 2030). Mining would be followed by 2 years of reclamation and 10 years of bond liability period (12 years total, until approximately 2046). The Mine’s recent coal production rate is 8.0 to 10.25 Million tons per year (Mtpy) across all mine permits. Production is forecast to decline after Colstrip Power Plant Units 1 and 2 are closed in 2022, averaging 8.3 Mtpy from 2023 to 2045 (WECo 2018e). Based on this average forecasted mining rate, the Proposed Action would add approximately 1.3 years to the overall mine life relative to the No Action Alternative when considered in the context of both currently permitted and proposed mining areas (i.e., Area F and Area B AM5). The maximum rate of mining from the passes including the LM Tracts and bypass coal could be as high as 3.0 Mt for a single year, which would occur in 2024 when mine-wide production is forecast to be 7.5 Mt (WECo 2018e).

The Area F DEIS analyzes the potential environmental effects of WECo’s proposed new mine permit area (C2011003F) known as Area F. Foreseeable activities related to mining, transporting and combusting coal in association with the Proposed Action are similar to activities described in the following sections of the Area F DEIS, and are incorporated by reference into this analysis:

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• Area F DEIS Section 1.2 describes an overview of coal transport and combustion. Most coal (up to approximately 8 Mtpy) would continue to be combusted at the Colstrip Power Plant and approximately 0.3 Mtpy of higher sulfur content and low calorific value would be combusted at the Rosebud Power Plant. Transport routes would utilize existing haul roads in the Area B and Area C mine permits (Figure 2) and transport distances to the conveyor and Rosebud Power Plant would be shorter than those described for Area F. • Area F DEIS Section 2.2 describes mine and reclamation operations, other existing permits, existing mine support facilities, the general sequence of operations, and the life of operations. This section also describes equipment and personnel that would continue to support mining the LM Tracts and bypass coal.

2.4 Alternative B – No Action Alternative

Under the No Action Alternative, the BLM would not approve the lease modifications and therefore subsequent recovery of coal resources in the LM Tracts would not occur. Coal in adjacent parcels that could not be economically mined without access to the LM Tracts would be bypassed. An estimated 10.8 Mt of coal, including 6.4 Mt of Federal coal, in the LM Tracts and bypass areas would not be recovered, transported, and combusted over the next 16 years, 209 acres would not be disturbed. If proposed mining in Area F and Area B AM5 is authorized, mining could continue until 2045, which is estimated to be 1.3 years less than if the LMA is approved (Proposed Action). Currently permitted mining and reclamation operations at the Mine and combustion at the Colstrip Power Plant and Rosebud Power Plant would continue as described in Section 2.3.

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CHAPTER 3 AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES

3.1 Introduction

This chapter describes the existing environment and the environmental consequences for six resource issues that the BLM determined could be affected by the Proposed Action and No Action Alternative described in Chapter 2. The analysis is intended to allow comparison of the alternatives and to present information useful for determining whether activities proposed would be expected to comply with applicable Federal, state, and local regulations.

Environmental data provided in the existing Area B and Area C mine permits and Area F DEIS are used in conjunction with relevant data from other cited data sources to describe the affected environment and to evaluate environmental effects of the alternatives. Impacts from current mining operations and anticipated cumulative impacts are described in the Area F DEIS as referenced in each resource section of this Chapter. Ongoing mining operations and permitted environmental protection measures employed in Area B and Area C are described in the current mine permits as discussed in Section 2.3.2.

Since approval of the LMA would not authorize any specific mining activities there would be no direct impacts relevant to the issues evaluated in this EA. However, mining, transport, and combustion of coal from the LM Tracts and bypass areas are foreseeable if the LMA is approved, as discussed in Section 2.3, and the associated effects would occur indirectly as a result of the Proposed Action. Many of the indirect effects analyzed in this action are similar to direct effects described in the Area F DEIS, which is incorporated by reference into this analysis.

The following terms are used in this analysis when discussing the context and intensity of effects (40 CFR § 1508.27):

Context • Localized: Changes are perceived at the location of the activity, but dissipate beyond the local setting. • Regional: Changes are perceived at a county level. • Short-term: Changes occur during the mining period or the estimated 12 years during which reclamation will occur following mining (2 years for grading and reclamation plus the 10-year liability period mandated by the MSUMRA). • Long-term: Changes remain after mining is complete and the 10-year liability period has passed.

Intensity • No Impact: No change in current activities or ongoing effects. • Negligible: Effects of activities would be so small as to not be detectable, resulting in no perceptible change in ambient conditions. • Minor: Effects from activities would show a change from current conditions, but would be clearly below regulatory or permitted standards.

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• Moderate: Effects from the proposed activities would show a larger change from current conditions, which are very close to regulatory or permitted standards. • Major: Effects from proposed activities would be detectable at a regional scale, a large enough increase in effects would require controls or mitigation to be implemented to meet regulatory or permitted requirements.

3.2 General Setting

The LM Tracts are located between 5 and 9 miles west of the city of Colstrip in Rosebud County, Montana (Figure 1). Situated in the northern Powder River Basin, the project area is generally east and north of the Little Wolf Mountains. The Northern Cheyenne Indian Reservation is located in Big Horn and Rosebud Counties approximately 11 miles south of the Area B LM Tract. The northeast corner of the Crow Reservation is located in Big Horn County approximately 12 miles southwest of the Area C LM Tract. The area overlying and surrounding the LM Tracts consists primarily of native grassland, introduced (non- native) pasture, silver sage and big sage grasslands, skunkbush sumac shrub-grassland, ponderosa pine grassland, mixed shrub, and deciduous tree/shrub (WECo, 2018a, 2018b; Exhibit E in both permits). Surface overlying the LM Tracts, bypass coal that would be mined under the Proposed Action, and adjacent parcels are all privately owned. Additional description of the LM Tracts and their vicinity is provided in the Area F DEIS (Section 3.1.2) and the 1994 Coal Lease Application MTM-80697 Draft EIS (BLM 1994, Chapter 3)

3.3 Past, Present, and Reasonably Foreseeable Actions

Under CEQ NEPA regulations, cumulative impacts are defined as impacts “on the environment which result from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions” per 40 CFR 1508.7. Detailed descriptions of the past, present, and reasonably foreseeable future actions in the Mine vicinity are presented in the Area F DEIS (Section 5.2), many of which affect the resources analyzed in this EA.

Past and present actions relevant to evaluation of cumulative effects include the following: • Historical and ongoing (permitted) mining and reclamation activities at the Rosebud Mine – The existing permits for Area A, Area B, Area C, Area D and Area E encompass approximately 25,455 acres (MDEQ 2017), including the LM Tracts and surrounding areas (see Area F DEIS Figure 117 for locations). Historical mining and ongoing activities at the Mine are discussed in the Area F DEIS (Section 2.2). • Historical mining and reclamation activities at the Big Sky Mine – As discussed in the Area F DEIS (Section 5.2.1.6), coal was historically mined at the Big Sky Mine located immediately south of the Area B permit boundary in Township 1 North, Range 41 East. The Big Sky Mine disturbed approximately 3,919 acres and is currently reclaimed (MDEQ 2017). • Operation of the Rosebud Power Plant and Colstrip Power Plant – In the Area F DEIS, coal combustion activities are summarized in Section 5.2.2.5, the two power plants are specifically discussed in the Section 1.2.2, air emissions are discussed in Section 3.3, and associated coal combustion residuals (CCR) are discussed in discussed in Sections 3.5.4.2 and 3.21.

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• Agricultural activity, including grazing – The project area and surrounding areas have been and continue to be used for agricultural purposes, primarily livestock grazing and conversion of native grassland to introduced pastureland, which have a substantial effect on land surrounding the LM Tracts. • Wildfire – Wildland fires have occurred in the Mine’s vicinity. Recent land cover data indicate that a portion of the Area B LM Tract and surrounding area was recently burned by a wildfire (MTNHP 2017). This recent burn may be associated with (or is adjacent to) the Chalky-Rosebud Complex fire, which burned over 132,000 acres beginning less than 1 mile southwest of the LM Tracts (DNRC 2017). • Air Emissions from Other Activities - Air emissions from other industrial activities in the region are discussed in the Area F DEIS (Sections 5.3.2 and 5.3.3). The Denbury EA (Appendix D) describes GHG emissions in the MCFO planning area.

Agricultural activity and wildfire are expected to continue for the reasonably foreseeable future as described above. Other reasonably foreseeable actions relevant to analysis of cumulative effects include the following: • Colstrip Power Plant and Rosebud Power Plant – Continued operation of the power plants is discussed in the Area F DEIS (Section 5.2.2.5) which notes that Colstrip Power Plant Units 1 and 2 are scheduled to be retired in 2022. Closure dates have not been set for Colstrip Power Plant Units 3 and 4 (hereafter “Units 3 and 4”) or the Rosebud Power Plant. Associated air emissions, CCR production and disposal would continue as described above. • Continued and Future Air Emissions from Other Activities – Existing emissions would likely continue as described above, except for decreases in emissions as Colstrip Power Plant Units 1 and 2 are retired. Overall mine emissions would change if mining operations progress into Area F and Area B AM5 as proposed. Future GHG emissions in the MCFO planning area are described in the Denbury EA (Appendix D). • Future Mining at Rosebud Mine: o Rosebud Mine Area F – Proposed mining of 70.8 Mt of coal over 19 years (potentially 2019 to 2037) is discussed in detail in the Area F DEIS. The proposed permit area is located approximately 3 miles west of the Area C LM Tract (Area F DEIS, Figure 117). o Rosebud Mine Area B AM5 – WECo recently applied for an amendment to Area B known as AM5. The amendment area is located south of the existing Area B permit boundary and add additional passes south of existing permitted passes (Figure 4). As proposed, mining associated with AM5 would add 9,108 acres allowing production of an additional 104.5 Mt of coal over 26 years (until 2045) (WECo 2018c, 2018d, 2018e). The proposed AM5 permit boundary and associated disturbance limit include the areas south and east of the Area B LM Tract, including the disturbance footprint associated with the Proposed Action. Portions of three mine passes identified as bypass coal associated with the Proposed Action abut the Area B LM Tract (Figure 3) and could instead be mined as part of the Area B AM5 (Figure 4).

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Figure 4. Reasonably Foreseeable Development of Area B AM5

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Based on available mine plan data, approximately 251 Mt of coal would be available for mining in the existing permit, proposed Area F and Area B AM5 permit areas, and LM Tracts and bypass areas after 2017. It is estimated that this coal would be mined, transported, and combusted over 30 years (until 2047), approximately 1.3 years longer than currently planned for Area B AM5 (WECo 2018e). Effects to some resources would continue over the following 12 years (until 2061) as disturbed areas are reclaimed (2 years) and bond release criteria are satisfied during the 10-year bond liability period.

3.4 Resource Issue 1 - Wildlife

Sharp-tailed grouse (Tympanuchus phasianellus), an upland game bird, is a BLM priority species for management because of public interest. The primary threats to sharp-tailed grouse populations include habitat loss and adverse weather. To address the threat of impacts to sharp-tailed grouse, the MCFO ARMP includes a management decision (MD WF 8; pg 3-4) requiring surface disturbances and disruptive activities within 2 miles of sharp-tailed grouse leks to include design features to protect breeding, nesting, and brood- rearing habitats. As noted in Section 1.4.3, this management decision is relevant to Unsuitability Criterion #15 (43 CFR Part 3461). In consideration of the MCFO ARMP management decision, the analysis area is the area within 2 miles of the LM Tracts and areas that would be disturbed in association with mining the LM Tracts and bypass coal. The cumulative effects analysis area is the area within a 2-mile buffer of the mine permits, proposed permits, and power plants.

3.4.1 Affected Environment

Sharp-tailed grouse are native to southeastern Montana and the Mine vicinity and the BLM manages habitat in the MCFO planning area where sharp-tailed grouse are widely dispersed. Sharp-tailed grouse typically inhabit grasslands interspersed with shrub and brush-filled coulees (MTNHP & MFWP 2018). Sharp-tailed grouse require a mosaic of dense grass and shrubs with rich forb and insect foods during nesting and brood- rearing (NatureServe 2018). During winter they often rely on riparian areas and other sites that support deciduous trees and shrub for feeding, roosting, and escape cover.

Breeding grounds (leks) for sharp-tailed grouse exist where surrounding habitat supports them and usually occur in open, elevated areas such as knolls, ridge tops, hilltops, benches, or flat areas providing a broad horizontal view of the surroundings (NRCS 2007). Leks are important because they are essential to reproduction and useful for monitoring population trends. Nests have been detected 50-1,600 meters (0.3- 1.0 miles) from leks, with 75 percent within 1 kilometer (0.6 mile) of a lek site (NatureServe 2018). Spring- to-fall home range sizes are generally less than a 2-kilometers (1.2-mile) radius around leks and seasonal movements to wintering areas from breeding grounds are typically less than 5 to 6.5 kilometers (3.1 to 4 miles) around leks, but more distant movements have been reported.

Approximately 1,483 sharp-tailed grouse dancing grounds (leks) have been documented in the MCFO planning area, with approximately 200 of these leks occurring on BLM-administered lands (BLM 2015b). The Mine’s monitoring program has identified 32 active sharp-tailed grouse leks within the Area A, Area B, Area C, Area D, and Area E permit boundaries, proposed Area F permit boundary and a variable buffer of approximately 0.3 to 2.6 miles (ICF 2017, Fenster 2018). Many of these leks correspond to historical leks reported by MFWP (Fenster 2018). Recent monitoring of the Area B AM5 survey area identified two additional active leks (ICF 2016). Other historical lek locations last monitored by MFWP between 1982 and 2001 are also present in the Mine vicinity (MFWP 2018); however, MFWP, BLM and the Mine neither

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individually nor combined monitor all identified leks on an annual basis. The most current lek surveys for this area have been conducted by the Mine’s contractors.

3.4.2 Environmental Impacts – Alternative A (Proposed Action)

While leks are not known to occur within the LM Tracts, mine monitoring (Fenster 2018, ICF 2016) has identified 10 active sharp-tailed grouse leks within 2 miles of the LM Tracts, potential bypass coal removal areas and associated additional surface disturbance described in Section 2.3.2. Active leks nearest to each LM Tract, respectively, are approximately 1.0 mile north of the Area B LM Tract and less than 0.1 mile south of the Area C LM Tract.

The Proposed Action’s effects on sharp-tailed grouse and their habitats are expected to be consistent with those described in the Area F DEIS (Section 4.12.3). Effects would primarily occur in the vicinity of the additional 209 acres of habitat disturbance associated with mining the LM Tracts and bypass coal. The additional surface disturbance would likely displace sharp-tailed grouse to other areas as they are somewhat mobile and likely to avoid areas of active mining and disturbed habitat. Mitigation and minimization measures such as soil salvaging outside of the spring months, phasing mine development areas, and establishing vegetation following mining would reduce impacts on sharp-tailed grouse. Reclamation described in the mine permits (WECo 2018a, 2018b, Section 17.24.313 and Exhibit C of both permits) emphasizes reestablishment of grassland and shrub-grassland communities using seed mixes composed of native grasses, forbs, and shrubs, which are capable of supporting sharp-tailed grouse in all seasons.

The Area F DEIS (Section 4.12.3) states that impacts from mining activities on sharp-tailed grouse appear to be short-term. This is based in part on long-term monitoring at the Mine where active leks on reclaimed areas have increased from seven in the early 1990’s (Waage 1992) to 13 leks in 2017 (Fenster 2018). Additionally, one of the active leks identified in the Area B AM5 survey area south of the Area B LM Tract is located in a reclamation area in approximately the same location as a historical lek extirpated by coal mining at the Big Sky Mine (MFWP 2018, ICF 2016), further documenting suitability of reclaimed mine lands as habitat for sharp-tailed grouse.

It is anticipated that the Proposed Action’s effects on sharp-tailed grouse would be short-term and minor provided that reclamation of additional disturbance associated with mining the LM Tracts and bypass coal is conducted in the same manner as described in the current mine permits. Impacts of the Proposed Action due to continued operation of support facilities, coal transport, and power plant operation would be comparable to the existing condition, although the duration of impacts would be extended by approximately 1.3 years relative to the No Action Alternative.

3.4.3 Environmental Impacts – Alternative B (No Action)

Under the No Action Alternative, coal in the LM Tracts and bypass coal would not be mined and the additional 209 acres of surface disturbance associated with that mining would not occur. Existing permitted mining activities would disturb approximately 88 percent of the surface overlying the Area B LM Tract and 50 percent of the surface overlying the Area C LM Tract. The surface overlying the LM Tracts would be reclaimed using reclamation methods described in the existing mine permit to restore predominantly native habitats. The duration of impacts associated with coal transport and combustion would be approximately 1.3 years less than the Proposed Action.

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3.4.4 Mitigation and Residual Effects

While habitats will be modified as a result of mining and reclamation, long-term residual effects related to sharp-tailed grouse will be minor. Reclamation performed using the methods described in the mine permits is proven to create habitats suitable for sharp-tailed grouse as demonstrated by the presence of active leks in reclaimed areas (Fenster 2018, ICF 2016). Reclaimed habitat suitability is affirmed by MDEQ in the Area F DEIS (Section 4.12.3.1). Considering these findings, Criterion 15 and the management decision in the MCFO ARMP (MD WF 8) discussed in Section 1.4.1 would be satisfied by stipulating the LM Tracts are reclaimed to native habitats with emphasis on grassland and shrub grassland using methods consistent with those specified in the existing mine permits. Such reclamation methods should use native seed mixes composed of a mixture of at least 4 grasses, 4 forbs, and 2 shrubs and implement supplemental plantings of native shrubs as needed to achieve reclamation objectives.

3.4.5 Cumulative Impacts

Cumulative effects described in the Area F DEIS (Section 5.3.11 and Section 5.3.12) include effects that would occur as a result of the Proposed Action and other past, present, and reasonably foreseeable future actions in the vicinity of the mine permits, proposed Area F, proposed Area B AM5, and the power plant permits. Area F DEIS discusses adverse cumulative effects on wildlife (Section 5.3.11) and special status species (5.3.12) including habitat loss, habitat alteration, habitat fragmentation, displacement, and increased competition. Impacts from mining would be mitigated in part by implementation of conservation practices and reclamation emphasis on grasslands and shrublands, which are suitable for sharp-tailed grouse.

Sharp-tailed grouse and their habitats are affected by past and ongoing mining activities, coal transport, and combustion and those effects will continue during the life of permitted mine activity. The most notable adverse effects of future mining on sharp-tailed grouse leks and habitat would occur as a result of new surface disturbance associated with expanded mining activity. At the end of 2017, 18,269 acres were disturbed within the mine permit boundaries, 54 percent of which was “soiled, seeded, and planted” and 35 percent of which was last “seeded or planted” at least 10 years ago (WECo 2018f, 2018g, 2018h, 2018i, 2018j). New disturbance associated with mining the LM Tracts and bypass coal (209 acres) is approximately 1 percent of the existing disturbance area. Proposed mining in Area F could disturb 4,260 acres (Area F DEIS, Section 1.1) and Area B AM5 could disturb an additional 5,525 acres (WECo 2018c), including the entire area that would otherwise be disturbed in association with mining the Area B LM Tract and associated bypass coal. Overall, currently permitted and proposed future mining would increase the mine disturbance by more than 50 percent relative to the existing condition. One active lek is located in areas that would be disturbed in association with mining in Area B AM5 (WECo 2018c, ICF 2016) and as many as five active leks may be located in areas that would be disturbed in Area F (Area F DEIS, Figure 51).

At the same time as additional mine disturbance occurs, contemporaneous reclamation would be completed in accordance with the mine permits, as required by MSUMRA and applicable regulations. Mine reclamation has been demonstrated to be suitable for sharp-tailed grouse, as noted in Section 3.4.2. If the requisite approvals are granted and mining continues as proposed, the duration of effects from mining would be extended and effects from mining would continue well beyond the 16 years during which the LM Tracts and associated bypass coal would be mined.

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Cumulative impacts of coal transport and power plant operation during the life of the Mine, including the Proposed Action, proposed Area F, and proposed Area B AM5 are expected to be similar to the existing condition during the life of mining. Mining, transport, and combustion effects would occur over the next 29 years without the LM Tracts and an additional 2 years (31 years total) if the LM Tracts and bypass coal are mined in conjunction with the Proposed Action.

Existing agricultural activities (e.g., grazing and cropland production) and other land uses in the vicinity of the mines, power plants, and transportation routes would continue to affect habitats in a manner similar to the existing condition. Fires would likely continue to alter habitats in localized areas, potentially reducing shrub and tree cover in favor of grassland habitats where they occur, as they have recently in the vicinity of the LM Tracts and Area B AM5 area (MTNHP 2017; DNRC 2017).

Overall, cumulative effects on sharp-tailed grouse are expected to be localized and minor relative to the existing condition, but effects would be long-term as future mining and related effects would continue after the LM Tracts and bypass coal areas are mined and reclaimed. In the long term, continued application of reclamation practices currently used by the Mine are expected to reestablish habitats suitable for sharp- tailed grouse ensuring populations do not decline.

3.5 Resource Issue 2 - Air Quality

Both alternatives analyzed in this EA have potential to affect air quality due to emissions from foreseeable coal mining, transport and combustion. Emissions affecting air quality include CAPs and HAPs, both of which can secondarily contribute to pollutant deposition and visibility degradation. Air quality effects from mining, transporting and combusting coal at the Mine were recently analyzed for a similar action in the Area F DEIS, which is incorporated by reference into this analysis.

Because air emissions disperse in the atmosphere, the analysis area for air quality impacts must necessarily be large. The affected environment varies from relatively near the project area when considering mining emissions, to a more regional scale for air pollution, visibility and atmospheric deposition from mining and coal combustion. Consistent with the Area F DEIS (Section 3.3.1.2, Section 5.3.2 and Figure 14), the analysis area for indirect and cumulative effects to air quality is a rectangular region encompassing a 300- kilometer radius circle and all Class I areas intersecting the 300-kilometer radius circle.

3.5.1 Affected Environment

Federal and state regulations applicable to coal production and combustion are discussed in the Area F DEIS (Section 3.3.1.1), which also describes applicable performance standards and air quality standards. National Ambient Air Quality Standards (NAAQS; EPA 2018a) and Montana Ambient Air Quality Standards (MAAQS; Annotated Rules of Montana, Title 17, Chapter 8; the MAAQS are hereafter understood to apply only to those portions of the analysis area that are within Montana) are presented in Area F DEIS Table 15. The climate of the analysis area is semiarid continental. Winds measured at Frank Wiley Field Airport in Miles City, MT are predominantly from the south-southeast and west-northwest (Area F DEIS Section 3.3.2). Miles City has the closest weather station to the mine with a complete dataset. While the weather at the mine may vary due to spatial and topographic differences, the Miles City weather station is still representative for the air and climate analysis.

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3.5.1.1 Mine Air Quality Monitoring

As discussed in Area F DEIS (Section 3.3.3), air quality at the Mine was monitored during most of the 1990s and again during a recent four-year period (2012-2016). Recent monitoring measured particulate matter less than 10 micrometers (μm) (PM10) and/or particulate matter less than 2.5 μm (PM2.5) at mine permit Areas A and F, generally located north and west of the LM Tracts, respectively. All monitored values show PM10 and PM2.5 to be well below national and state ambient air quality standards except for the 2015 PM2.5 value, which was near but below the standard. Monitored PM10 and PM2.5 values are summarized in Area F DEIS Table 16 and Table 17.

3.5.1.2 Existing Regional Air Pollutant Sources and Emissions

The Area F DEIS (Section 3.3.4) identifies emissions from existing emission sources in the analysis area and provides detailed quantification of CAPs and HAPs from these sources. Emissions are separately presented for the Mine (Section 3.3.4.1, Table 18), Colstrip Power Plant, Rosebud Power Plant (Section 3.3.4.2, Tables 19 to 24), and sources elsewhere in the analysis area (Section 3.3.4.3, Table 25).

3.5.1.3 Regional Air Quality

The Area F DEIS (Section 3.3.5) summarizes air quality in the analysis area and includes a description of CAPs (Section 3.3.5.1), other air-quality related values, or AQRVs, such as visibility and regional haze (Section 3.3.5.2), and atmospheric deposition (Section 3.3.5.3). These sections of the Area F DEIS also identify the following locations in the analysis area: • NAAQS nonattainment and maintenance areas (Tables 26 and 27); • Interagency Monitoring of Protected Visual Environments (IMPROVE) (i.e. visibility monitoring) sites (Table 28 and Figure 17); and, • Atmospheric deposition monitoring stations (Table 29 and Figure 19), including o National Atmospheric Deposition Program (NADP) monitoring sites (i.e., National Trends Network, or NTN), o Clean Air Status and Trends Network (CASTNET) (i.e., atmospheric deposition) monitoring sites, and, o NADP Mercury Deposition Network (MDN) monitoring sites. The Area F DEIS concluded the following with respect to regional air quality in the analysis area: • Existing air quality is generally clean with regard to ambient air quality standards; • Visibility in the Class I area nearest to the Area F project shows no clear positive or negative trend in visibility over a recent thirteen-year period; and, • Deposition of sulfur, nitrogen, and mercury as measured at the above referenced monitoring stations (Area F DEIS, Table 29 and Figure 19) are relatively small compared to national deposition rates and especially compared to deposition rates in the eastern U.S.

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3.5.2 Environmental Impacts – Alternative A (Proposed Action)

The Area F DEIS (Section 4.3) quantifies air emission impacts from the development and operation of proposed Area F which would have a mining rate of approximately 4.0 Mtpy. As discussed in Section 2.3, mining associated with the Proposed Action could be as high as 3.0 Mtpy, which would occur in 2024 when mine-wide production is forecasted to be approximately 7.5 Mt. Impacts identified for Area F can be, in most cases, directly proportioned as a means to describe the impacts from mining in association with the Proposed Action. Based on forecasted mining rates and the highest potential mining rate under the Proposed Action, max-year 2024 emissions associated with the Proposed Action would be approximately 75 percent of the emissions quantified for Area F (3.0 Mtpy vs 4.0 Mtpy from Area F) and 40 percent of mine-wide emissions (3.0 Mtpy vs 7.5 Mtpy mine-wide in 2024). Four impact intensity levels used to qualitatively address the severity of air quality effects in the Area F DEIS (Section 4.3.1.2, Table 98) are also used in this analysis.

3.5.2.1 Effects of Coal Production

The Area F DEIS (Section 4.3, and tables and figures presented therein) describes the analysis and findings related to Area F mining-related impacts on air resources within the analysis area, which are referenced throughout this section. Consistent with the action analyzed in the Area F DEIS, the Proposed Action would increase both the period of mining and total disturbance area associated with the Mine but would not increase total annual coal production of the Mine across all permitted areas. WECo’s Montana air quality permit (MAQP) #1570-07 and MAQP #1483-08 may require modification to reference areas permitted to be mined prior to coal production at the LM Tracts and bypass areas.

For this analysis, assumptions pertaining to mine-related emission sources are consistent with those presented in the Area F DEIS (Section 4.3.3) and were used to conservatively evaluate impacts from air emissions associated with the Proposed Action since coal production at the LM Tracts and bypass coal areas will be less than potential coal production at Area F. For instance, truck haulage fugitive emissions associated with the Proposed Action are based on Area F haul road distance. However, haul road distances from the LM Tracts to the coal processing facilities in Area C are shorter than from Area F, resulting in a slight overestimation of emissions in this analysis. No adjustment of haul road distance was made when proportioning emissions from the Area F DEIS to the Proposed Action.

Criteria Air Pollutant Emissions

Maximum potential annual emissions of CAPs from coal production under the Proposed Action presented in Table 2 are scaled emissions based on estimates presented in the Area F DEIS.

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Table 2. Estimated Criteria Air Pollutant Emissions Associated with Coal Production Under the Proposed Action, tons/year1 2 Emission Source(s) PM10 PM2.5 NOx CO SO2 VOC Topsoil Removal 14.11 1.41 ------Topsoil Dumping 0.51 0.08 ------Overburden Drilling 0.20 0.02 ------Overburden Blasting – Cast Blasting 21.74 1.25 ------Overburden Removal by Dragline 45.30 3.99 ------Overburden Handling by Truck/Shovel 70.89 1.79 ------Overburden Dumping 0.51 0.08 ------Overburden Handling by Dozer 6.99 3.87 ------Haul Roads – Travel 147.70 14.68 ------Access Roads – Unpaved 45.63 4.57 ------Coal Drilling 0.04 0.00 ------Coal Blasting 7.96 0.46 ------Coal Removal 0.05 0.01 ------Mobile Sources Diesel Exhaust – Haul/Water 6.87 6.87 177.51 42.79 0.22 11.28 Trucks Mobile Sources Diesel Exhaust – Grader 0.05 0.05 0.72 0.25 0.00 0.06 Mobile Sources Diesel Exhaust – Dozers 2.66 2.57 59.52 17.26 0.06 3.96 Explosives -- -- 55.17 217.41 6.49 -- Disturbed Acres – Complete (< 2 Yr.) 7.50 0.75 ------Disturbed Acres – Complete (> 2 Yr.) 0.00 0.00 ------Disturbed Acres – Facilities 0.00 0.00 ------Disturbed Acres – Partial (< 1 Yr.) 25.26 2.52 ------Disturbed Acres – Partial (> 1 Yr.) 22.52 2.25 ------Disturbed Acres – Pits, Peaks, Soil Stripping 200.84 20.08 ------Portable/Stationary Equipment – Gasoline 0.19 0.19 3.07 1.87 0.16 5.71 Engines Waste Coal Hauling to Rosebud Power Plant 0.20 0.17 4.75 1.30 0.00 0.23 Truck Dump – Coal 0.04 0.01 ------Coal Crushing 0.09 0.01 ------Coal Conveyors 0.02 0.00 ------Total 627.86 67.65 300.74 280.88 6.93 21.24 (1) Values estimated from Area F DEIS Table 100 based on the ratio of maximum projected annual coal production due to the Proposed Action (3,014,183 tons) to the Area F annual coal production rate (4,000,000 tons). (2) VOC – volatile organic compounds

Hazardous Air Pollutant Emissions

Trace metal HAP emissions from fugitive coal dust (Table 3) and potential diesel particulate matter (DPM) emissions (Table 4) from coal production under the Proposed Action are scaled emissions based on estimates presented in the Area F DEIS.

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Table 3. Trace Metal Hazardous Air Pollutant Emissions from Fugitive Coal Dust Associated with Coal Production Under the Proposed Action1 Concentration in Project Area Coal HAP Emissions Metal HAP (ppm) (lb/year) Antimony 0.30 4.91E-03 Arsenic 0.72 1.18E-02 Beryllium 0.28 4.58E-03 Cadmium 0.04 6.55E-04 Chromium 2.56 4.19E-02 Copper 5.05 8.29E-02 Lead 3.75 6.14E-02 Manganese 70.59 1.15E+00 Mercury 0.03 4.28E-04 Nickel 0.91 1.49E-02 Selenium 0.55 9.04E-03 (1) Values estimated from Area F DEIS Table 101 based on the ratio of maximum projected annual coal production due to the Proposed Action (3,014,183 tons) to the Area F annual coal production rate (4,000,000 tons).

Table 4. Diesel Particulate Matter Emissions Associated with Coal Production Under the Proposed Action1 Emissions Source(s) DPM (tons/year) Mobile Sources Diesel Exhaust - Haul/Water Trucks 6.87 Mobile Sources Diesel Exhaust - Grader 0.05 Mobile Sources Diesel Exhaust - Dozer 2.57 Waste Coal Hauling to Rosebud Power Plant 0.17 Total Project Area DPM 9.65 (1) Values estimated from data presented in Area F DEIS Table 102 based on the ratio of maximum projected annual coal production due to the Proposed Action (3,014,183 tons) to the Area F annual coal production rate (4,000,000 tons).

Air Concentrations and Related Values – Criteria Air Pollutants and Precursors

The Area F DEIS (Figure 71 through Figure 76) presented modeled impacts of coal production at Area F on the surrounding ambient air quality. The findings are representative of expected air quality impacts from coal production under the Proposed Action. However, since the highest potential mining rate under the Proposed Action would be lower than that of Area F, impacts described in the Area F DEIS overestimate impacts that would occur under the Proposed Action.

Modeled impacts from the Area F project on ambient concentrations of nitrogen dioxide (NO2) mostly occur near or within the Mine. Modeled impacts on ozone (O3) concentrations reach more widely into surrounding counties. However, Area F project impacts on NO2 and O3 ambient air concentrations were determined to be well below NAAQS and MAAQS in the analysis area. Area F coal production impacts on PM2.5 and PM10 emissions also occur near or within the Mine and predicted ambient concentrations are well below the NAAQS. Modeled PM10 concentrations are also well below the MAAQS (there is no MAAQS for PM2.5). Modeled impacts of Area F coal production sulfur dioxide (SO2) and carbon monoxide (CO)

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emissions predict ambient concentrations of these pollutants well below the respective NAAQS and MAAQS for those pollutants in the analysis area. Therefore, consistent with the Area F DEIS (Section 4.3.3), impacts from coal production emissions of NO2, O3, PM2.5, PM10, SO2, and CO under the Proposed Action would be short-term, minor, and adverse in the analysis area.

Air Quality Related Values – Nitrogen and Sulfur Deposition

Results of nitrogen and sulfur deposition modeling presented in the Area F DEIS (Section 4.3.3) can be used to evaluate potential impacts of coal production under the Proposed Action. There are no regulatory thresholds with regard to atmospheric deposition of air emissions. Therefore, modeled annual deposition due to the Proposed Action is compared to the modeled cumulative annual deposition if the Area F project were not approved to assess the relative intensity of impacts. Area F DEIS (Table 103) lists modeled maximum and average nitrogen and sulfur deposition rates at the 18 Class I areas in the analysis area. The highest modeled deposition rate (nitrogen maximum, 0.0084 kilograms per hectare (kg/ha); nitrogen average, 0.0045 kg/ha) was determined to have a negligible impact on Class I areas. Since the rate of mining under the Proposed Action would be lower than the rate modeled for Area F, nitrogen and sulfur deposition rates from coal production under the Proposed Action would also have negligible, short-term impacts to Class I areas in the analysis area.

Visibility

The Area F DEIS (Table 104) summarizes modeled visibility impairment (haze) at the same nearby 18 Class I areas due to coal production at Area F. The model predicted no days in a year with a change in deciviews (Δdv) (i.e., haze index) greater than 0.5 due to the Area F project. The highest 98th percentile Δdv over a year is 0.377 modeled at the Northern Cheyenne Indian Reservation. Thus, the Area F DEIS determined that visibility impairment at those sites due to Area F coal production would be negligible. Consistent with the analysis above, visibility impairment due to coal production under the Proposed Action is also expected to be negligible and short-term.

Hazardous Air Pollutant Deposition

Modeled deposition of HAP metals, coal dust-related PM10, and DPM in the Area F DEIS (Table 105, Figure 77, and Figure 78, respectively) shows that air concentrations and deposition rates of these pollutants decline rapidly with distance from the Mine. Annual average air concentration and annual deposition of PM10 (which includes HAP metals contained within coal dust) were found to be less than 0.05 micrograms per cubic meter (μg/m3) and 50.0 kg/ha, respectively, beyond the mine boundary. Since HAP metals are present in coal dust at levels less than 10 parts per million (ppm) (except for manganese (Mn), which is measured at about 71 ppm in coal dust) (Table 101), annual HAP metal deposition rates are expected to be less than 3.5 grams per hectare (g/ha) for Mn and less than 188 milligrams per hectare (mg/ha) for lead (Pb), which are two HAP metals present in coal dust at higher concentrations. Although the forms of the Pb standards are different than the values listed in Table 105, the modeled maximum Pb air concentration was determined to be negligible (5.63E-07 μg/m3 Pb) with respect to the NAAQS (0.15 μg/m3 Pb, rolling three-month average) and MAAQS (1.5 μg/m3, 90-day average) values, so ambient Pb concentrations would be expected to be below the NAAQS and MAAQS. Annual average air concentration of DPM was found to be generally less than 0.1 μg/m3 beyond the mine boundary. Therefore, indirect impacts from HAP deposition due to coal production following approval of the Proposed Action are

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expected to be similar and slightly lower. Based on the analysis presented in the Area F DEIS, indirect impacts of HAP deposition on the analysis area would be long-term, minor, and adverse.

3.5.2.2 Effects of Coal Combustion

The total amount of coal burned at the Colstrip and Rosebud Power plants on an annual basis would not increase as a result of the Proposed Action. Colstrip Power Plant Units 1 and 2 are to be retired in 2022, and the Proposed Action would not affect the rate of combustion, timing of closure, or total amount of coal to be combusted in those units. It is assumed that the produced coal from the Proposed Action would extend the life of the Mine and thus add to the emissions produced by Units 3 and 4. Therefore, Units 3 and 4 and Rosebud Power Plant are the combustion locations most relevant to this analysis.

Criteria Air Pollutant and Hazardous Air Pollutant Emissions

The Area F DEIS (Table 106 through Table 108) list CAP and HAP emissions from Units 3 and 4 and the Rosebud Power Plant. Table 106 lists CAP emissions from these combustion locations based on the DEQ annual emission inventory reporting records for 2015, which is a recent and representative year. Since annual combustion emissions from Units 3 and 4 and the Rosebud Power Plant would not change, these values represent the same emissions that would occur during the period of mining under the Proposed Action. Although only 40 percent (at most) of coal combusted in a given year would be generated by mining associated with the Proposed Action (see Section 3.5.2.1), the duration of power plant operations would be extended by approximately 1.3 years relative to the No Action Alternative (see Section 2.3). Therefore, total annual plant emissions are analyzed.

Air Concentrations of Criteria Pollutants

The Area F DEIS (Figure 79 through Figure 84) show the modeled effects (intensity and extent) of CAP emissions from Units 3 and 4 and the Rosebud Power Plant on the analysis area. The maximum modeled concentrations of NO2, O3, PM2.5, PM10, and SO2 were well below the NAAQS and MAAQS. Consistent with the Area F DEIS, coal combustion emissions of NO2, O3, PM2.5, PM10, and SO2 would have short- term, minor, and adverse air quality impacts in the analysis area. Cumulative impacts of CO emissions, considering all regional sources including combustion of Area F coal, were well below the NAAQS and MAAQS. Consistent with the Area F DEIS, coal combustion emissions of CO due to the Proposed Action would have negligible impacts in the analysis area.

Air Quality Related Values – Nitrogen and Sulfur Deposition

Nitrogen deposition and sulfur deposition in Class I areas from Area F coal combustion were analyzed in the same manner as coal production emissions. Model results presented in the Area F DEIS (Table 110) were somewhat higher than from Area F coal production (Table 101). The contribution of the project to nitrogen deposition at the Northern Cheyenne Indian Reservation, the Class I area with the highest impact, when considering the spatial average in the area, is 4.6 percent. Other Class I areas were predicted to experience relative impacts from 0.1 to 0.5 percent from nitrogen deposition resulting from Area F coal combustion. The contribution of the project to sulfur deposition at the Northern Cheyenne Indian Reservation, when considering the spatial average in the area, is 13.5 percent; other Class I areas would have relative impacts ranging from 0.1 to 1.6 percent from project-related sulfur deposition. Consistent with the findings of the Area F DEIS, nitrogen and sulfur deposition rates from coal combustion associated with

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the Proposed Action would have long-term, minor, and adverse effects on the 18 Class I areas in the analysis area.

Visibility Impairment

Visibility impairment at the same 18 Class I areas discussed above was assessed for indirect impacts associated with coal combustion (Area F DEIS, Section 4.3.3.2, Table 111). Across the Class I areas in the analysis area, the change in haze index exceeds 1.0 on seven days or less except at Northern Cheyenne where it is exceeded 20 days in the year. The change in haze index (Δdv) exceeds 0.5 on fourteen days or less except at Northern Cheyenne where it is exceeded 96 days in the year with a 98th percentile Δdv of 1.425. Consistent with the Area F DEIS findings, coal combustion emissions associated with the Proposed Action would have short-term, minor, and adverse effects on visibility in Class I areas within the analysis area.

Hazardous Air Pollutant Deposition

Trace metal emissions from coal combustion were modeled and analyzed in the Area F DEIS to evaluate effects of metal deposition in the analysis area (Table 112 and Figure 85 through Figure 92). Modeled deposition rates of the trace metals are highest near Units 3 and 4 and decease with increasing distance from Colstrip Power Plant. Mercury deposition due to Area F coal combustion is a few percent of total mercury deposition in the analysis area. Consistent with modeling results presented in the Area F DEIS, metal deposition, in particular mercury deposition, resulting from coal combustion under the Proposed Action would have long-term, minor, and adverse effects in the analysis area.

3.5.2.3 Air Quality Effects on Public Health

The NAAQS and MAAQS are health-based standards for ambient air quality. Consistent with the analysis presented in the Area F DEIS (Section 4.3) and air quality analysis presented above, the Proposed Action would not cause an exceedance of these standards.

The Area F DEIS (Section 4.5.3.1) concluded that DPM and fugitive coal dust are the most likely source of risk to public health due to coal production at Area F. Limited public exposures would likely occur on county roads and areas used for recreation adjacent to the Mine, and the time of exposure would generally be short. Consistent with the Area F DEIS, limited potential exposure to DPM and fugitive coal dust from the Proposed Action would result in negligible to minor, short-term, and adverse public health impacts.

Health impacts associated with air emissions from Area F coal combustion are presented in Area F DEIS (Section 4.5.3.2). Predicted air concentrations are expected to remain below NAAQS and MAAQS, and PM2.5 and PM10 are expected to remain well below the NAAQS in the analysis area. Consistent with the Area F DEIS, health impacts due to coal combustion resulting from the Proposed Action would have a negligible to minor, short-term, and adverse effect on public health.

3.5.3 Environmental Impacts – Alternative B (No Action)

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the Mine and coal combustion would continue at the Colstrip and Rosebud Power plants at essentially the same rates as under the Proposed Action. The effects on air quality would be the same as for the Proposed Action discussed in Section 3.5.2, but the duration of mining, combustion, and associated air quality impacts would be reduced by approximately 1.3 years relative to the Proposed Action.

3.5.4 Mitigation and Residual Effects

No mitigation beyond that contained in existing permits is needed for the Proposed Action. No residual effects to air quality are anticipated to occur beyond those described above.

3.5.5 Cumulative Effects

The Area F DEIS (Section 5.3.2 and Appendix D-6) describe cumulative impacts from Area F coal production and coal combustion on the analysis area when combined with other past, present and reasonably foreseeable actions. As discussed in Section 3.5.2, mining activities and coal combustion associated with the Proposed Action are similar to that analyzed for Area F. Therefore, cumulative effects would also be similar, as summarized in this section. Consistent with the Area F DEIS (Section 5.3.2), the cumulative effects analysis considers air emissions from coal mining, coal combustion, the Colstrip Airport, BLM land management, oil and gas development, rail transport, wildland fire, and other sources in the analysis area. Climate change (see Section 3.6) also influences the long-term cumulative impacts of air emissions, since changes in temperature and precipitation patterns are known to influence O3 and particulate pollution. While climate’s influence on air pollution should be recognized, it is difficult to accurately predict or quantify climate’s long-term influence on air quality.

3.5.5.1 Cumulative Impacts on Air Quality

Criteria Air Pollutants and Precursors

The Area F DEIS (Appendix D-6, Table D-6-1 through Table D-6-5) identifies future air emissions from the Mine, Colstrip Power Plant Units 1 and 2, other major regional point sources, mine-generated fugitive coal dust, and mine-generated DPM, respectively, as summarized in Section 5.3.2.1. Spatial distributions of cumulative CAP emission effects on air quality are presented in Area F DEIS Appendix D, Figure D-6- 1 through Figure D-6-12 and summarized in Section 5.3.2.2.

As previously noted, annual CAP emissions from the Proposed Action would not increase relative to the No Action Alternative, but coal production and combustion would continue for 1.3 years longer. Modeled cumulative effects of CAP emissions on air quality in the analysis area would be comparable to those presented in Area F DEIS (Section 5.3.2.2).

Maximum cumulative concentrations of the eighth highest 1-hour daily maximum NO2 and annual average NO2 within the analysis area are 74.7 parts per billion (ppb) and 17.8 ppb, respectively, and are found near Gillette, Wyoming (WY). No NAAQS or MAAQS exceedances were modeled for NO2. The maximum cumulative impacts on the second highest 1-hour daily maximum O3 and fourth highest daily maximum 8- hour O3 within the analysis area are 68.3 ppb and 63.5 ppb, respectively, and are found on the border shared by Sublette and Fremont Counties in Wyoming. These modeled O3 values are below the NAAQS (70 ppb). Maximum impacts from the proposed Area B AM5 on 1-hour (4.2 ppb) and 8-hour (2.1 ppb) are found near the southern border of AM5. The maximum second highest 1-hour and 8-hour CO are 0.9 and 0.4 ppm,

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which are well below the NAAQS and MAAQS. Consistent with the Area F DEIS, cumulative effects on NO2, O3, and CO would be short-term, minor, and adverse.

3 The maximum eighth highest daily average cumulative PM2.5 (45.2 μg/m ) and annual average PM2.5 (20.2 μg/m3) occur in the central-eastern part of Campbell County in NW WY, which is the only area that shows 3 modeled exceedance of the daily PM2.5 NAAQS (35 μg/m ) and one of two areas not attaining NAAQS for 3 annual average PM2.5 (12 μg/m ). Big Horn County, Montana (MT), near the MT-WY border, is the other area. Based on model results, maximum cumulative effects on ambient PM2.5 concentrations in the Mine vicinity, in units of the NAAQS, are an eighth highest daily average of 12.1 μg/m3 and an annual average 3 of 6.0 μg/m . Consistent with the Area F DEIS, cumulative impacts for PM2.5 in the area near the Mine and the two power plants are short-term, minor, and adverse; cumulative impacts for PM2.5 in the wider analysis area are short-term, moderate, and adverse.

3 The maximum second highest daily cumulative PM10 within the analysis area (243.7 μg/m ) is near Gillette, 3 WY and exceeds the daily NAAQS (150 μg/m ). The maximum annual average PM10 within the analysis area is 82.8 μg/m3, located in Bighorn County, Montana, near the WY border, exceeds the MAAQS (50 3 μg/m ; there is no annual PM10 NAAQS). Peak PM10 concentrations in both cases were found to be dominated by other regional sources. Cumulative impacts for PM10 in the area near the Mine and the two 3 power plants are well below the NAAQS and MAAQS for daily PM10 (maximum 84.1 μg/m ) and below 3 the MAAQS for annual PM10 (maximum 31.2 μg/m ). Consistent with the Area F DEIS, cumulative impacts for PM10 in the area near the Mine and the two power plants are short-term, minor, and adverse; cumulative impacts for PM10 in the wider analysis area are short-term, moderate, and adverse.

The spatial maxima within the analysis area of the fourth highest daily maximum 1-hour SO2 (87.4 ppb), second highest 3-hour SO2 (79.2 ppb), second highest 24-hour SO2 (46.2 ppb), and annual average SO2 (21.2 ppb) occur in the NE corner of Fremont County, WY. The 3-hour and 24-hour maxima are well below the corresponding NAAQS (140 ppb for 24-hour and 500 ppb for 3-hour) and MAAQS (100 ppb for 24- hour). The 1-hour maximum exceeds the NAAQS (75 ppb) but is below the MAAQS (500 ppb). The peak annual average is above the MAAQS (20 ppb) but below the NAAQS (30 ppb). Peak SO2 concentrations were found to be dominated by other regional sources. Cumulative impacts for SO2 in the area near the Mine and the two power plants are well below the NAAQS and MAAQS for the different forms of the SO2 standards. Consistent with the Area F DEIS, cumulative impacts for SO2 in the area near the Mine and the two power plants are short-term, minor, and adverse; cumulative impacts for SO2 in the wider analysis area would be short-term, moderate, and adverse.

Based on the modeled results for Area F, the Proposed Action would have a short-term, minor, and adverse contribution to cumulative concentrations of CAPs in the area near the Mine and the two power plants. In the wider analysis area, the Proposed Action would have a short-term, minor and adverse contribution to cumulative concentrations of NO2, O3, and CO, and short-term, moderate, and adverse contribution to cumulative concentrations of PM2.5, PM10, and SO2.

Nitrogen and sulfur deposition

Modeled spatial distribution of annual cumulative acid deposition of nitrogen and sulfur compounds within the analysis area are presented in the Area F DEIS (Appendix D-6, Figure D-6-14 and Figure D-6-15).

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Cumulative annual impacts of nitrogen and sulfur acid deposition on Tribal and Federal Class I areas within the analysis area are also listed in the Area F DEIS (Appendix D-6, Table D-6-6). Consistent with effects described for Area F (Section 5.3.2.2), nitrogen and sulfur emissions from the Proposed Action would contribute less than 0.1 percent nitrogen and sulfur deposition at the most impacted Class I areas in the analysis area.

Critical loads of nitrogen-based acidity and sulfur-based acidity were obtained for 471 lakes and streams in the analysis area, and cumulative nitrogen and sulfur deposition was modeled and analyzed for critical acidity loads in the lakes and streams (Area F DEIS; Section 5.3.2.2, Appendix D-6, Figure D-6-16 and Figure D-6-17). That analysis determined cumulative nitrogen and sulfur deposition rates exceeded the critical load at 16 and 20 locations, respectively. Area F project indirect nitrogen emissions contributed less than 0.4 percent cumulative nitrogen deposition, and direct nitrogen emissions contributed a smaller, negligible fraction at these locations. Area F project indirect sulfur emissions contributed up to 1.2 percent cumulative sulfur deposition, and direct sulfur emissions contributed a negligible fraction at these locations. Consistent with the Area F analysis, the Proposed Action would have negligible, long-term, and adverse cumulative effects on nitrogen and sulfur deposition in the analysis area.

Visibility and regional haze

The Area F DEIS (Section 5.3.2.2, Appendix D-6, Table D-6-7) summarizes findings and lists the cumulative change in haze index in Class I areas in the analysis area and the percentage of the cumulative change due to direct and indirect impacts associated with Area F. Across the Class I areas in the indirect/cumulative impacts analysis area, the change in haze index due to cumulative impacts varies from 7.8 to 26.4 Δdv, with peak values modeled at Medicine Lake National Wildlife Refuge and Flathead Indian Reservation. This analysis also lists the number of days during which the change in haze index due to direct and indirect impacts from the Area F project exceeds 0.5 or 1.0 at each Class I area analyzed. The Area F DEIS (Appendix D-6, Table D-6-8) presents data published by the Environmental Protection Agency (EPA) on changes in haze index due to Units 3 and 4 for comparison purposes, showing exceedances of the 0.5 Δdv threshold on 7 days at the Theodore Roosevelt National Park.

Consistent with the Area F analysis referenced above, the Proposed Action would have moderate, short- term, and adverse cumulative effects on visibility and regional haze in the analysis area.

Hazardous Air Pollutants – Fugitive Coal Dust and Diesel Particulate Matter

The Area F DEIS (Appendix D-6, Table D-6-9) lists maximum annual average air concentration and annual deposition of HAPs from mine-wide fugitive coal dust emission. Spatial distribution of annual average air concentration of PM10 and annual deposition of fugitive coal dust due to proposed Area B AM5 emissions, as well as emissions from all coal dust emissions from current and future areas at the Mine are also presented (Area F DEIS, Figure D-6-18, Appendix D-6). Maximum coal dust concentration and deposition occur within the boundaries of Area B AM5, and impacts decrease rapidly with distance from the Mine.

Spatial distribution of annual average DPM air concentrations due to Area B AM5 and total current and future mine-related diesel exhaust emissions is presented in the Area F DEIS (Figure D-6-19, Appendix D- 6). Maximum modeled DPM emissions (0.29 µg/m3) due to coal production activities at AM5 occur within Area B AM5 while maximum DPM emissions (0.37 µg/m3) due to all mine-related diesel exhaust emissions occur within Area C. Modeled DPM emissions drop rapidly with distance from the Mine boundary.

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Consistent with the analysis in Area F DEIS (Section 5.3.2.2), both cumulative fugitive coal dust emissions and cumulative DPM emissions due to indirect impacts from the Proposed Action are expected to result in similar concentrations and deposition patterns, which would have minor, short-term, and adverse cumulative effects on air quality in the analysis area and minor, long-term, and adverse cumulative effects on deposition of HAPs in the analysis area.

Hazardous Air Pollutants - Mercury Deposition

The Area F DEIS (Appendix D-6, Table D-6-10) lists the estimated contribution of Units 3 and 4 and Rosebud Power Plant mercury emissions to regional wet mercury deposition as measured at the Badger Peak MDN site. Modeled contributions from these mercury emissions are all less than 1.0 percent of measured mercury values. Since Units 3 and 4 and the Rosebud Power Plant are expected to operate at rates similar to current rates in the future, the Proposed Action’s cumulative effects on wet mercury deposition in the analysis area would be similarly low.

The Area F DEIS (Appendix D-6, Table D-6-11) also lists cumulative wet plus dry mercury deposition and the estimated relative contribution of Units 3 and 4 and Rosebud Power Plant to wet plus dry mercury deposition. Modeled results estimate that the cumulative contribution of Units 3 and 4 and Rosebud Power Plant would be relatively minor.

Consistent with the findings for Area F (Section 5.3.2.2), contribution of the Proposed Action to cumulative mercury deposition in the analysis area is relatively small and would therefore have minor, long-term, and adverse cumulative effects.

Effects on Public Health

Consistent with the analysis presented in the Area F DEIS (Section 5.3.4), past, ongoing, and future activities at the Mine and Colstrip and Rosebud Power plants will affect air quality. Cumulative impacts from mine operations and power plant activities and continued emissions of HAPS and PM may impact public health, particularly for individuals living proximal to the Mine or power plants with compromised respiratory and circulatory health. Consistent with the Area F DEIS, cumulative health impacts within the area of other air pollution sources would be short- to long-term, minor to major, and adverse, to which the Proposed Action would contribute negligibly.

3.6 Resource Issue 3 - Climate

As noted in the Area F DEIS (Section 3.4.1), climate change refers to any measurable deviation in climate that lasts for an extended period—several decades or longer—and includes recordable changes in temperature, precipitation, or wind patterns. Changes in climate can result from both human and natural factors, including emissions of GHGs into the atmosphere. Because GHG travel long distances and remain in the atmosphere for extended lengths of time, their effects are worldwide rather than localized. Considering this, and consistent with the Area F DEIS (Section 3.4.1.2), the analysis area for climate and climate change is the world with focus on the United States (US) and Montana.

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3.6.1 Affected Environment

The Area F DEIS presents background information regarding climate change and the role of human activities in the current warming trend (Section 3.4.1) followed by a description of the current regulatory framework pertaining to GHG emissions (Section 3.4.1.1). The Area F DEIS (Section 3.4.2) discusses climate conditions, including atmospheric composition and common GHG produced from human activities. Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) are the GHGs identified for inventory and analysis.

Each GHG has a Global Warming Potential (GWP) that accounts for the intensity of its heat trapping effect and its longevity in the atmosphere. GWP values allow for comparison of emissions’ effects by putting various GHGs on a common scale (carbon dioxide equivalents; CO2e). GWP metrics have been developed for several GHGs over different time horizons including 20-year, 100-year, and 500-year. The choice of emission metric and time horizon depends on the type of application and policy context; no single metric is optimal for all policy goals. The 100-year GWP was adopted by the United Nations Framework Convention on Climate Change and the associated Kyoto Protocol and is now used widely as the default metric (EPA 2018b). The EPA also uses the 100-year time horizon in the Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2016 (EPA 2018c) and GHG Reporting Rule requirements under 40 CFR Part 98 Subpart A. The EPA considers GWP estimates presented in the most recent scientific assessment by the Intergovernmental Panel on Climate Change (IPCC) to reflect the state of the science. GWP values presented in the IPCC Fifth Assessment Report (IPCC 2013) are used in this assessment. These values may differ from GWP values used in the Area F DEIS and elsewhere to convert CH4 and N2O to CO2e, but they reflect the latest published science. In this analysis, the 100-year GWPs are the primary values used to evaluate potential effects on climate and 20-year GWPs are presented for comparison (Table 5).

Table 5. Global Warming Potential of Greenhouse Gasses as Carbon Dioxide Equivalents Greenhouse Gas 100-Year GWP 20-Year GWP Carbon Dioxide - CO2 1 1 Methane - CH4 34 86 Nitrous Oxide - N2O 298 268 Source: "2013 Climate Change, The Physical Science Basis," IPCC, 5th Assessment, Chapter 8, Page 714.

Area F DEIS Section 3.4.2.3 presents global, national, and regional climate and GHG emissions trends. In that same section, Table 31 and Table 32 report 2015 GHG emissions from major source categories in Montana and the 20 largest GHG emission sources within 300 kilometers of the Mine, respectively. The Mine’s GHG emissions are tabulated in Area F DEIS Section 3.4.2.4 and historic GHG emissions from the Colstrip and Rosebud Power plants are provided and discussed in Section 3.4.2.5 (all on a 100-year GWP basis). Additionally, estimated global, national, state and regional climate projections are discussed in Section 4.4.2.1, Section 4.4.2.2, and Section 4.4.2.3. These data collectively provide background and describe the affected environment to support analysis of climate effects.

3.6.2 Environmental Impacts – Alternative A (Proposed Action)

Coal mining, transport, and combustion are foreseeable in association with the Proposed Action (see Section 2.3.2). These actions would emit GHGs and thereby affect the climate. Estimated GHG emissions

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from mining, transporting, and combusting the maximum annual production of coal (approximately 3.0 Mt) from the LM Tracts and bypass areas are presented in Table 6. The 100-year values can be compared to annual GHG emissions from other mine permit areas and coal combustion presented in the Area F DEIS (Section 4.4.2.4 and Section 4.4.3.2, respectively).

Table 6. Estimated Maximum Annual Greenhouse Gas Emissions Associated with the Proposed Action

Project CO2 CH4 N2O CO2e 100-Year CO2e 20-Year Segment1 (Metric (Metric (Metric (Metric Tons/ year) (Metric Tons/ Tons/year) Tons/ year) Tons/ year) year) Mining and 28,082 2023 0.3 96,974 202,174 Transport2 Combustion3 5,216,635 577 84 5,261,252 5,288,751 Total 5,244,717 2600 84.3 5,358,226 5,490,925 (1) Emissions for each segment based on the ratio of maximum annual production under Proposed Action (3,014,183 tons) to the mining rate analyzed in the Area F DEIS (4,000,000 tons) and the combustion of coal in Units3&4 and Rosebud plants in 2015. (2) Mining and transport emissions estimated from data presented in Area F DEIS Table 121. (3) Combustion emissions estimated from data presented in Area F DEIS Table 123. Total combustion emissions from Units 3&4 and Rosebud Plants are reported in the table. Data were scaled to maximum annual production from LM Tracts based on a total coal feed rate of 7.04 Mtpy for all three plants.

For this analysis, the relative intensity of potential effects of the Proposed Action on climate is assessed by comparing maximum potential annual GHG emissions from the Proposed Action to annual statewide, national, and global GHG emissions (Table 7). The Proposed Action comprises approximately 25 percent of Montana’s reported 2016 emissions available through EPA’s Greenhouse Gas Reporting Program (GHGRP) Flight Tool (EPA 2018d). Further, based on these estimates, the Proposed Action emissions would comprise 0.08 percent of US emissions totals (EPA, 2018c), and approximately 0.01 percent of global totals (IPCC 2014). Because GHGs are considered a pollutant with global scale impacts, comparison with global totals is most meaningful.

Table 7. Comparisons with Montana, US and Global Annual Greenhouse Gas Emissions Totals

CO2e 100-Year Scale (Million Metric Tons/yr) Proposed Action Annual Maximum 5.4 Montana1 21.1 United States2 6511 Global3 54,000 (1) Includes only emissions from large industrial sources reported to EPA annually as part of the Greenhouse Gas Reporting Program, Source: EPA 2018d (2) Source: EPA 2018c (3) Source: IPCC 2014

GHG emissions associated with the Proposed Action and mine-wide coal production can also be evaluated against GHG emissions from an average US vehicle and home (EPA 2018e). The estimated maximum annual emissions associated with the Proposed Action would be equivalent to those from 2 million cars or 1 million homes.

Total GHG emissions from mining and combusting approximately 10.8 Mt of coal from the LM Tracts and bypass areas under the Proposed Action is presented in Table 8.

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Table 8. Estimated Total Greenhouse Gas Emissions Associated with the Proposed Action

Project CO2 CH4 N2O CO2e 100-Year CO2e 20-Year Segment1 (Metric Tons) (Metric (Metric (Metric Tons) Metric Tons Tons) Tons) Mining and 100,422 7,235 1.2 346,785 722,986 Transport2 Combustion3 18,655,020 2,064 300 18,814,574 18,912,913 Total 18,755,442 9,299 301 19,161,359 19,635,899 (1) Emissions for each segment based on the ratio of total LM Tract and bypass coal to be mined under the Proposed Action (10,778,911 tons) to the mining rate analyzed in the Area F DEIS (4,000,000 tons) and the combustion of coal in Units 3 and 4 and Rosebud Plants in 2015. (2) Mining and transport emissions estimated from data presented in Area F DEIS Table 121. (3) Combustion emissions estimated from data presented in Area F DEIS Table 123. Total combustion emissions from Units 3&4 and Rosebud Plants are reported in the table. This data was scaled to total production from LM Tracts based on a total coal feed rate of 7.04 million tons for all three plants.

Based on this analysis and the supporting information incorporated by reference, the GHG emissions associated with the Proposed Action would have long-term, negligible, and adverse global effects on climate.

3.6.3 Environmental Impacts – Alternative B (No Action)

Under the No Action Alternative, existing mine operations would continue and produced coal would be transported and combusted at the Colstrip and Rosebud Power plants. Annual emissions from mining activity and combustion at these power plants would not change as coal would be produced from other areas of the Mine. However, under the No Action Alternative 10.8 Mt less coal would be mined, total GHG emissions would be approximately 19 million metric tons less (100-year GWP basis), and the total mine life would be approximately 1.3 years shorter, relative to the Proposed Action.

3.6.4 Mitigation and Residual Effects

No residual effects to climate are anticipated to occur beyond those described above. No mitigation beyond that contained in existing permits is needed for the Proposed Action. However, the mine operator has implemented best management practices to reduce GHG and CAP emissions, including:

• Recently purchasing equipment with Tier 3 engines to reduce emissions. • Use of large capacity equipment, that uses less fuel per the amount of material moved. • Apply dust suppressant during summer months, which reduced fuel used by water trucks. • Implementation of LED lighting throughout the mine where possible.

3.6.5 Cumulative Effects

GHG emissions from the Proposed Action are combined with other sources in the MCFO planning area to assess cumulative effects on climate. GHG emission sources include reasonably foreseeable sources of GHG emissions in the planning area including mineral production and transportation, as well as downstream emissions from combustion of fossil fuel resources extracted from the planning area. The Denbury EA Appendix D (BLM 2018a) provides a detailed assessment of these emissions and is hereby incorporated by reference.

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The relative intensity of GHG emission effects on climate are assumed to be proportional to emission rates since climate change impacts result from the atmospheric buildup of GHGs, which are eventually distributed throughout the atmosphere (IPCC 2013). Table 9 summarizes annual GHG emissions from the Proposed Action, reported emissions from the State of Montana, estimated emissions from the MCFO planning area, US emissions, and global emissions based on 100-year GWPs. The calculated difference in CO2e emissions based on the 20- and 100-year GWPs are minimal for the Proposed Action and MCFO planning area. GHG emissions from the Proposed Action and the MCFO ARMP area would both contribute to climate change as discussed in Section 3.6.1.

Table 9. Greenhouse Gas Emission Comparisons

CO2e 100-Year Scale (Million Metric Tons/yr) Proposed Action 5.4 Montana1 21.1 MCFO ARMP Area2 98.5 United States3 6511 Global4 54,000 (1) Includes only reported emissions from large industrial sources, Source: EPA 2018d (2) Source: BLM 2018a, Denbury EA (3) Source: EPA 2018c (4) Source: IPCC 2014

Annual GHG emissions from the Proposed Action represent approximately 5 percent of the emissions expected to result from all MCFO resource development contributions, including reasonably foreseeable coal mining, transport and combustion. Future GHG emissions from resource development in the MCFO planning area emissions are 1.0 percent and 0.2 percent of US and global GHG emissions, respectively. Results are also presented below in Table 10 based in terms of EPA GHG equivalency metrics (EPA, 2018e).

Table 10. Greenhouse Gas Emission Comparisons in terms of Greenhouse Gas Equivalency Scale Number of Cars Number of Homes LM Mining Total 1.1 million 0.58 million MCFO ARMP Area 21 million 11 million

Total GHG emissions associated with mining 10.8 Mt of coal in association with the Proposed Action (Table 9) would be approximately 4.0 percent of the emissions associated with mining 251 Mt from existing permitted areas, Area F, and Area B AM5.

Based on these data, the Proposed Action would contribute to global GHG emissions, but would have a negligible, long-term impact on climate due to the small quantity of emissions relative to other emissions sources.

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3.7 Resource Issue 4 - Noise

Consistent with the Area F DEIS, the analysis area for noise includes the rural areas surrounding the Mine (existing permit boundaries and Area F) to the north, south, and west, and residential areas to the east within the incorporated city of Colstrip. Individual residences are scattered throughout the rural area.

The analysis area for cumulative noise impacts is consistent with that analyzed in the Area F DEIS and includes Colstrip, existing permit areas of the Mine, proposed Area F, and a buffer area to the north, south, west, and east that includes portions of Rosebud, Treasure, and Big Horn Counties (including the Colstrip and Rosebud Power plants).

3.7.1 Affected Environment

Noise regulations, terminology, and existing noise sources are discussed in Area F DEIS (Section 3.22.1). Environmental noise levels are not regulated within or near the analysis area. In the absence of regulations, thresholds based on EPA guidance discussed in the Area F DEIS (Section 3.22.1.3) are useful for characterizing the existing condition and gauging noise effects.

The Area F DEIS (Section 3.22.2) describes existing noise levels within the analysis area which are currently affected by ongoing mine operations (e.g., blasting, excavation, coal haulage), traffic along State Highway 39 and other local roads, the county-owned and operated airfield, the Colstrip Power Plant, and to a lesser extent the Rosebud Power Plant located 6 miles to the north. Environmental noise levels in any given area can fluctuate as noise sources move and environmental factors change.

Several residences and the city of Colstrip are located in the analysis area (Area F DEIS, Figure 64 and Table 9). The nearest residences in Colstrip are anywhere from 1 to 2 miles away from active mining operations, however these residences are affected by operation of coal conveyor systems and, commuting workers, haul trucks, and supply trucks driving through Colstrip on Highway 39 and associated mine access roads. Several other residences are located between 0.7 and 11.7 miles of the existing Mine (Area F DEIS, Table 90 and Figure 64).

3.7.2 Environmental Impacts – Alternative A (Proposed Action)

Impact thresholds applicable to this analysis are consistent with those used to evaluate impacts in the Area F DEIS (Section 4.1.1, Table 163).

Noise-related impacts associated with the Proposed Action would continue in a manner comparable to the existing condition with no discernable change in intensity at local residences or the city of Colstrip. Effects related to the Proposed Action would occur during the 16 years that the LM Tracts and bypass coal are mined and could occur for an additional 1.3 years relative to the No Action Alternative. The level and intensity of noise associated with future mining of the LM Tracts and associated bypass coal would be comparable to that generated from existing activities and facilities associated with the existing mine areas. However, the precise location of noise generation and, by association, the distance to receptors (e.g., residences) would vary within the LM Tracts and bypass coal areas as mining progresses.

The nearest residence (residence “R1”; Area F DEIS, Table 90 and Figure 64) is located approximately 1.1 mile from areas that would be mined and 1.0 miles from areas that would be disturbed in association with

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the Proposed Action (Figures 2 and 3). In comparison, the same residence is located approximately 0.9 mile west of permitted mining and 0.8 mile west of permitted surface disturbance in Area B and 1.1 miles south of currently authorized mining and 1.0 miles south of permitted surface disturbance in Area C. Other residences and the city of Colstrip (Area F DEIS, Figure 64) are located over 3 miles distant and are closer to existing and permitted mine operations than mining and reclamation that would occur under the Proposed Action.

Based on these distances, future mining and surface disturbing activities associated with the LM Tracts under the Proposed Action would not occur closer to the nearest residence than existing permitted mining passes; therefore, the level and intensity of noise-related impacts to the nearest residence would not change. However, there would be a change in duration of that activity as mining in the Area C LM Tract and adjacent bypass coal and subsequent reclamation would continue an additional 1.3 years relative to the No Action Alternative. Consistent with the analysis presented in the Area F DEIS, impacts due to noise generated from mining and reclamation activities within the two LM tracts would be localized, adverse, short- and long- term, and range from negligible to minor for the nearest rural residences.

Effects of coal transport (haulage and conveyor) and combustion activities on local noise levels would be consistent to those discussed in the Area F DEIS (Section 4.22.3.2). While a portion of the noise would be attributed to the LM Tract coal and bypass coal, noise levels would not change as a result of the Proposed Action during the 16-year period of mining. Coal would continue to be transported via conveyor to the Colstrip Power Plant and haul trucks would continue to transport coal to the Rosebud Power Plant and impacts would continue consistent with present conditions for the residences in Colstrip.

Consistent with the analysis presented in the Area F DEIS (Section 4.22.3.2), localized noise effects from the Colstrip Power Plant operation would continue and would be long-term, adverse and moderate for the residences in Colstrip. Similarly, noise effects would be localized, long-term, adverse, and minor to moderate for the residences proximal to the Rosebud Power Plant (Area F DEIS Figure 116, Table 167). While the intensity of these noise impacts would not change, the duration of those impacts could be extended as a result of the Proposed Action as the coal available for mining would potentially extend the mine life by approximately 1.3 years relative to the No Action Alternative. Consistent with the analysis presented in the Area F DEIS (Section 4.22.3.2), impacts due to noise generated from transport and combustion activities at the Colstrip Power Plant and Rosebud Power Plant would be negligible for the nearest rural residences.

3.7.3 Environmental Impacts – Alternative B (No Action)

Under the No Action Alternative, BLM would not approve the proposed lease modification application and WECo would not mine the LM Tracts or associated bypass coal. The No Action alternative would not change the current status of the existing Mine. The residence nearest to the LM Tracts would continue to be affected by nearby mining for 6 years (until 2024) and would be subsequently affected by reclamation activities. Mining and surface disturbance in Area B would occur within 0.9 and 0.8 miles of the residence, respectively. Existing noise producing activities and sources associated with current mine permits and proposed mining areas (including Area F and Area B AM5) and associated coal transport and combustion operations could continue for approximately 27 years (until 2045), approximately 1.3 years less than would occur under the Proposed Action.

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3.7.4 Mitigation and Residual Effects

No residual noise effects are anticipated to occur beyond those described above. No mitigation is needed for the Proposed Action.

3.7.5 Cumulative Impacts

Past, present, and reasonably foreseeable future actions that have, would continue, or may contribute to cumulative noise-related impacts in the future include current (Area A, B and C) and proposed (Area F and Area B AM5) operations at the Mine, nearby agricultural operations, airport operations, as well as coal combustion at the Colstrip and Rosebud Power plants. As discussed in the Area F DEIS (Section 5.3.21), the only current continuous noise sources in proximity to any residences are the Colstrip and Rosebud Power plants which the Area F DEIS estimated as having a moderate long-term cumulative impact on Colstrip residences directly west of the Colstrip and Rosebud Power plants. All other cumulative noise sources (e.g., Rosebud County airstrip, current mining operations, etc.) are considered distant from residences and would result in minor to negligible on-term cumulative impacts.

The addition of the LM tracts to currently permitted and proposed mining operations by approximately 2 years, from 2045 to 2047 (see Section 2.3). Moderate cumulative localized impacts on the Colstrip residences directly west of the Colstrip and Rosebud Power plants would continue in the long-term (possibly 31 years) as mining in Area B AM5 could continue an additional 15 years after the 16 years of mining under the Proposed Action. The Proposed Action would contribute to continued minor long-term cumulative impacts on the other residences in Colstrip due to transport and combustion, and result in continued negligible to minor long-term cumulative impacts on residences near the Area B and C permit boundaries. While mining occurring as a result of the Proposed Action would have localized noise impacts, operations are not expected to contribute cumulatively to regional noise due to the distances of receptors from these activities.

3.8 Resource Issue 5 - Waste and Pollution

Existing mine operations and subsequent coal combustion generate wastes with potential to cause pollution and affect the environment. Consistent with the Area F DEIS (Section 3.21.1.2 and Figure 63), the analysis area for indirect effects on waste and pollution includes the entire Mine, the Colstrip and Rosebud Power Plants, and off-site CCR storage areas associated with the Colstrip Power Plant. The analysis area for cumulative effects is also consistent with that analyzed in the Area F DEIS (Section 5.3.20 and Figure 117) and includes the indirect effects analysis area plus the Rosebud County Landfill where solid wastes would be sent, as well as any off-site disposal areas where hazardous wastes generated would reside.

3.8.1 Affected Environment

The Area F DEIS discusses waste classification (Section 3.2.1.1) and Federal and state regulations and terminology pertaining to the management and disposal of solid and hazardous waste (Section 3.21.1.1). As discussed in Area F DEIS (Section 3.21.2) wastes generated as part of active coal mining within Areas A, B and C of the Mine are handled under WECo’s Waste Management Program consisting of a Solid and Hazardous Waste Management Plan (SHWMP), a Spill Prevention Control and Counter Measures Plan

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(SPCCMP), and a Contingency and Emergency Response Plan (CERP). The Mine is a Large Quantity Generator as defined by the Resource Conservation and Recovery Act (RCRA).

Non-hazardous waste is collected in dumpsters throughout the Mine and transported to the Rosebud County Landfill (Area F DEIS, Figure 63) by truck for final disposal. Certain mining-related non-hazardous waste can also be placed in the mine pits in accordance with ARM 17.24.507. Petroleum-contaminated soil generated by tank removals, spills, or sump cleanouts is hauled to Area A for treatment by land-farming.

No CCRs are generated at the Mine. However, dewatered bottom-ash waste generated from the Colstrip Power Plant is beneficially applied at the Mine as tank- or culvert-bedding material, at parking facilities, and as a road-sanding material when needed. Beneficial use of dewatered bottom ash at the Mine is dependent on MDEQ-required monitoring and reporting requirements (Area F DEIS, Section 3.21.2.2 and Figure 63).

Hazardous wastes are collected in 55-gallon drums at various locations throughout the Mine (satellite accumulation points), which vary depending on mine activity, and are transported to the hazardous-waste storage area located in Area A (Area F DEIS, Figure 63) for shipment to an off-site treatment, storage, and disposal facility. Additional details and descriptions of the hazardous-waste storage area in Area A, including ongoing monitoring and reporting, is provided in Area F DEIS Section 3.21.2.3.

As noted in Section 3.3, CCR waste is generated in association with coal combustion. CCR generated by the Colstrip Power Plant is impounded in ponds at the plant site and at two separate locations about 3 miles east (Effluent Holding Pond) and northwest (Stage Two Evaporation Pond) of Colstrip, respectively (Area F DEIS Section 3.21.2.4 and Figure 63). CCR generated by the Rosebud Power Plant is conveyed pneumatically to an ash silo for temporary storage, then periodically transferred into a plant-ash truck and transported to an on-site ash monofill disposal area where it is hydrated with industrial wastewater from the plant to consolidate and solidify the ash (Area F DEIS Section 3.21.2.5).

3.8.2 Environmental Impacts – Alternative A (Proposed Action)

Impact thresholds applicable to this analysis are consistent with those used to evaluate impacts in the Area F DEIS (Section 4.1.1, Table 162).

Waste and pollution-related impacts associated with the Proposed Action would continue in a manner consistent with existing operations, but those effects would occur during the 16 years that the LM Tracts and bypass coal are mined and could occur for an additional 1.3 years relative to the No Action Alternative.

No new waste management facilities or storage areas would be required due to the Proposed Action. Hazardous waste would continue to be collected at various locations depending on location of mining (satellite accumulation points) and transported to the hazardous waste storage area in Area A for shipment to an off-site facility. Continued implementation of the SHWMP, SPCCMP and CERP would limit potential release of solid or hazardous wastes stored in Area A or in any of the satellite accumulation points and resultant adverse effects would be localized, negligible and short-term.

WECo would continue to dispose of non-coal solid waste at either the Rosebud County Landfill or in mine pits in an approved on-site landfill site for solid wastes. Excess waste liquid not used at the Mine would be handled under WECo’s Waste Management Program. Given continued implementation of existing

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practices, adverse effects of non-coal solid waste and liquid waste disposal would be localized, negligible and short-term.

Colstrip and Rosebud Power Plants would continue to generate CCR in proportion to the amount of coal burned at the plants for an additional 1.3 years relative to the No Action Alternative. Coal produced in association with the LM Tracts (including bypass coal) would add to the amount of CCR generated. Beneficial use of CCR (bottom ash) would continue during the period of mining, consistent with the analysis in Area F DEIS (Section 4.21.3.2). Impacts from associated boron toxicity would be short-term and negligible given that the beneficial use is contingent on meeting requirements of the MDEQ-required monitoring plan.

As reported in Area F DEIS (Section 4.8.3.2), over the period of operation, seepage from various lined ponds has resulted in measurable impacts on groundwater beneath the plant site. Groundwater impacts at the Colstrip Power Plant have been characterized and are being remediated via capture wells, preventing offsite migration. As a result of seepage from ponds to groundwater, the Colstrip Power Plant has modified its operations to use ponds with clay liners for storm water runoff only; CCR is now stored in synthetically lined ponds. With the exception of accidental spills, which cannot be predicted, burning of project-area coal at the Colstrip Power Plant would not likely result in any indirect impacts on groundwater because of the recent operational changes at the plant.

3.8.3 Environmental Impacts – Alternative B (No Action)

Under the No Action Alternative, BLM would not approve the proposed LMA and WECo would not mine the LM Tracts or associated bypass coal. The No Action Alternative would not change the current status of the existing Mine. Management of waste streams and pollution would continue under WECo’s existing Waste Management Program. Existing waste and pollution producing activities and sources associated with currently permitted mine and proposed mining areas (including Area F and Area B AM5) and associated coal transport and combustion operations could continue and would have effects comparable to the Proposed Action. However, the duration waste generating activities would be 1.3 years less and the quantity of waste generated would be reduced by the proportion associated with approximately 10.8 Mt of coal that would otherwise be mined in association with the Proposed Action.

3.8.4 Mitigation and Residual Effects

No residual waste or pollution effects are anticipated to occur beyond those described above. No mitigation beyond that contained in existing permits is needed for the Proposed Action.

3.8.5 Cumulative Impacts

Past, present, and reasonably foreseeable future actions that have, would continue, or may contribute to cumulative waste and pollution-related impacts in the future include current (Area A, B and C) and proposed (Area F and Area B AM5) operations at the Mine as well as coal combustion at the Colstrip and Rosebud Power Plants resulting in the CCR production. As discussed in the Area F DEIS (Section 5.3.20), mining has contributed to the generation of solid and hazardous waste and would continue to add to the total amount of solid and hazardous waste already generated. Coal combustion would add to the amount of

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CCR generated and stored at the power plants and bottom ash would continue to be used at the Mine consistent with current practices.

The addition of the LM tracts to currently permitted and proposed mining operations would extend operations and associated waste generation for approximately 1.3 years, from 2045 to 2047 (see Section 2.3). Consistent with the analysis in Area F DEIS (Section 5.3.20), coal mining associated with the Proposed Action would contribute relatively small quantities of solid and hazardous waste to landfills and disposal areas compared to amounts received from past and proposed (Area F and AM5) activities. The associated waste disposal would have short-term negligible and adverse cumulative impacts on the landfill and disposal areas receiving solid or hazardous wastes from the Mine.

Similarly, cumulative impacts as a result the Proposed Action from the use of CCR at the Mine would be short-term, negligible and adverse due to the small quantities used, MDEQ-required monitoring to identify adverse impacts, and reclamation practices that would be conducted where CCR is used.

Since the rate of mining would not change under either alternative, the annual rate of CCR production would not change. Cumulative effects would relate only to the quantity of CCR produced. Therefore, cumulative effects of CCR production associated with the Proposed Action would be short-term and negligible relative to past, ongoing, and future CCR production. There would be no cumulative effects on groundwater due to CCR production because of the recent operational changes at the Colstrip Power Plant, as discussed above.

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LIST OF PREPARERS

This EA was prepared by a third party NEPA contractor with guidance, participation and independent evaluation by BLM. BLM, in accordance with 40 CFR § 1506.5 (a and b), has approved and takes full responsibility for the scope and content of the EA. BLM staff and NEPA contractor staff who assisted in preparation of this EA are identified in Table 11 and Table 12, below.

Table 11. BLM staff. Name Title Role Carissa Shilling Geologist Project Lead Kathy Bockness Planning and Environmental Coordinator NEPA Coordinator Andy Daniels Wildlife Biologist Wildlife Doug Melton Archaeologist Cultural and Historic Resources, Section 106 Eric Vernon Air Resource Specialist Air Quality and Climate Jessica Montag Socioeconomic Specialist Socioeconomics/Environmental Justice

Table 12. NEPA contractors. Name Organization Project Responsibility Education/Experience Project Manager, Primary B.S. Land Rehabilitation Judd Stark Catena Consulting Author 18 years of experience M.S. Resource Administration Assistant Project Manager, Laura Pfister NewFields & Management Primary Author 19 years of experience B.A. Urban Studies Karen Lyncoln Catena Consulting Primary Author, Editor 40 years of experience B.S. Natural Resource Conservation/Biology, Bruce Waage Catena Consulting Wildlife Review Certified Wildlife Biologist 35+ years of experience M.S. & B.S. Environmental Engineering, Jeff Chaffee Bison Engineering Air Quality / Climate Registered Professional Engineer, 40 years of experience B.S. Chemical Engineering, M.S. Soil Science, M.A. Applied Mathematics, Erica Shuhler Bison Engineering Air Quality / Climate Registered Professional Engineer, 16+ years of experience

October 2018 45

REFERENCES

Bureau of Land Management (BLM). 1983. The Federal Coal Lands Review Process for the 1984 Powder River Resource Management Plan. Powder River Resource Area, Miles City District, Montana. January 1984.

BLM. 1984. Powder River Resource Area Resource Management Plan, Miles City District. Final Environmental Impact Statement. December 1984.

BLM. 1985. Record of Decision, Powder River Resource Management Plan, Powder River Resource Area, Miles City District, BLM. March 1985.

BLM. 1994. Draft Western Energy Company Coal Lease Application (MTM-80697) Environmental Impact Statement. Miles City District Office. January 1994.

BLM. 1996. Record of Decision and Approved Big Dry Resource Area Management Plan. BLM Miles City District Office., Montana. April 1996.

BLM. 2015a. Miles City Field Office Approved Resource Management Plan. September 2015.

BLM. 2015b. Record of Decision and Approved Resource Management Plan Amendments for the Rocky Mountain Region, Including the Greater Sage-Grouse Sub-Regions of Lewistown, North Dakota, Northwest Colorado, Wyoming and the Approved Resource Management Plans for Billings, Buffalo, Cody, Hi-Line, Miles City, Pompey’s Pillar National Monument, South Dakota, and Worland. September 2015.

BLM. 2015c. Miles City Field Office Proposed Resource Management Plan and Final Environmental Impact Statement. June 2015.

BLM. 2018a. Cedar Creek Anticline CO2 Pipeline and EOR Development Projects Environmental Assessment. DOI-BLM-MT-C020-2017-0081-EA. Available Online At: https://eplanning.blm.gov/epl-front- office/projects/nepa/89883/155107/189825/Denbury_CO2_Pipeline_Project__EA.pdf Accessed On: August 22, 2018.

BLM. 2018b. Scoping Report for the Environmental Assessment for the Western Energy Company Lease Modification for Federal Coal Lease MTM 80697. October 2018.

Environmental Protection Agency (EPA). 2018a. National Ambient Air Quality Standards (NAAQS) Table. Available Online At: https://www.epa.gov/criteria-air-pollutants/naaqs-table Accessed On: October 1, 2018.

EPA. 2018b. Environmental Protection Agency (EPA). Greenhouse Gas Emissions, Understanding Global Warming Potentials. Available at: https://www.epa.gov/ghgemissions/understanding- global-warming-potentials. Accessed on: September 15, 2018.

October 2018 46 References

EPA. 2018c. Environmental Protection Agency (EPA). Greenhouse Gas Emissions, Inventory of U.S. Greenhouse Gas Emissions and Sinks. Available at: https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks. Accessed on: August 15, 2018.

EPA. 2018d. Environmental Protection Agency (EPA). Greenhouse Gas Emissions, 2016 Greenhouse Gas Emissions from Large Facilities. Available at: https://ghgdata.epa.gov/ghgp/main.do. Accessed on August 15, 2018.

EPA. 2018e. Environmental Protection Agency (EPA). Greenhouse Gas Emissions Equivalency Calculator, Calculations and References, Available at: https://www.epa.gov/energy/greenhouse- gases-equivalencies-calculator-calculations-and-references. Accessed on August 16, 2018.

Fenster, R. 2018. Email from Roy Fenster (Project Manager/Biologist, ICF) to Carissa Shilling (BLM), Subject: Rosebud Mine Grouse Monitoring. May 22, 2018.

ICF. 2016. Appendix F. Rosebud Mine, Area B Tract – 2013 through 2015 wildlife baseline. October 2016. Submitted with Area B AM5 Application package. Available Online At: http://deq.mt.gov/Public/ea/coal Accessed On August 24, 2018.

ICF. 2017. Rosebud Mine 2016 Wildlife Monitoring. Prepared for Western Energy Company (WECo). February 2017.

Intergovernmental Panel on Climate Change (IPCC). 2013: Anthropogenic and Natural Radiative Forcing. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

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Montana Department of Environmental Quality (MDEQ). 2017. 2017 Annual Report, Air, Energy & Mining Division: Coal and Opencut Mining Bureau – Coal Section. Available Online At: http://deq.mt.gov/Portals/112/Land/CoalUranium/Documents/Annual%20Reports/2017_Report.p df Accessed On: September 4, 2018.

Montana Department of Natural Resources and Conservation (DNRC). 2017. January 9, 2017 email from Elizabeth Hertz (DNRC) to Judd Stark (Catena Consulting, LLC) transmitting boundaries of areas burned by wildfires in watersheds encompassing the Rosebud Mine.

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Western Energy Company (WECo). 2018a. Surface Mine Permit C1984003B, Rosebud Mine Area B.

WECo. 2013. Application for Coal Lease Modification, Lease No. MTM 80697. Rosebud Mine. September 12, 2013.

WECo. 2018b. Surface Mine Permit C1985003C, Rosebud Mine Area C.

WECo. 2018c. GIS Data transmittal and mine pass timing provided to BLM in response to Data Request #4. August 7, 2018.

WECo. 2018d. Email from Wade Steere (WECo) to Carissa Shilling (BLM), Subject: Tons Tables for LMA. August 3, 2018.

WECo. 2018e. Email from Dicki Peterson (WECo) to Carissa Shilling (BLM), Subject: Need Clarification of Data. September 13, 2018.

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WECo. 2018f. March 30, 2018 letter from Dicki Peterson (WECo) to Chris Yde (MDEQ), Subject 2017 Annual Mining Report, Permit C1986003A, Area A.

WECo. 2018g. March 30, 2018 letter from Dicki Peterson (WECo) to Chris Yde (MDEQ), Subject 2017 Annual Mining Report, Permit C1984003B, Area B.

WECo. 2018h. March 30, 2018 letter from Dicki Peterson (WECo) to Chris Yde (MDEQ), Subject 2017 Annual Mining Report, Permit C1985003C, Area C.

WECo. 2018i. March 30, 2018 letter from Dicki Peterson (WECo) to Chris Yde (MDEQ), Subject 2017 Annual Mining Report, Permit C1986003D, Area D.

WECo. 2018j. March 30, 2018 letter from Dicki Peterson (WECo) to Chris Yde (MDEQ), Subject 2017 Annual Mining Report, Permit C1981003E, Area E.

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