United States Department of the Interior

Office of Surface Mining Reclamation and Enforcement

Environmental Assessment

Spring Creek Mine

Big Horn County, Montana

Mining Plan

for

Federal Coal Lease MTM-069782

May 2020

Prepared by:

U.S. Department of the Interior

Office of Surface Mining Reclamation and Enforcement Program Support Division

1999 Broadway, Suite 3320

Denver, CO 80202

PH: 303-293-5000 / FAX: 303-293-5032

Spring Creek Mine TR1 EA i

TABLE OF CONTENTS 

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

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

1.3 Purpose and Need ...........................................................................................................................1-7

1.4 Regulatory Framework and Necessary Authorizations ..........................................................1-7

1.5 Outreach and Issues .......................................................................................................................1-8

1.6 Crosswalk of Resource Areas ......................................................................................................1-8

1.7 Public Involvement ..........................................................................................................................1-8

2.0 Proposed Action and Alternatives ............................................................................... 2-1

2.1 Description of the Alternatives ....................................................................................................2-1

2.2 Existing Conditions (Conditions Common to the Proposed Action and the No 

Action Alternative) ..........................................................................................................................2-4

3.0 Affected Environment ................................................................................................... 3-1

3.1 General Setting ................................................................................................................................3-1

3.2 Topography and Physiography ......................................................................................................3-1

3.3 Geology, Minerals, and Paleontology ..........................................................................................3-1

3.4 Air Quality and Climate Change ..................................................................................................3-1

3.5 Water Resources ..........................................................................................................................3-14

3.6 Alluvial Valley Floors .....................................................................................................................3-18

3.7 Wetlands/Aquatic Features .........................................................................................................3-19

3.8 Soils ...................................................................................................................................................3-19

3.9 Vegetation .......................................................................................................................................3-19

3.10 Wildlife ........................................................................................................................................3-19

3.11 Land Use and Recreation ........................................................................................................3-24

3.12 Cultural Resources ...................................................................................................................3-24

3.13 Visual Resources .......................................................................................................................3-24

3.14 Noise ............................................................................................................................................3-24

3.15 Transportation ...........................................................................................................................3-25

3.16 Hazardous and Solid Wastes ..................................................................................................3-26

3.17 Socioeconomics .........................................................................................................................3-26

4.0 Environmental Consequences/Cumulative Effects ..................................................... 4-1

4.1 Introduction ......................................................................................................................................4-1

4.2 Topography and Physiography ......................................................................................................4-3

4.3 Geology, Mineral Resources, and Paleontology ........................................................................4-4
TABLE OF CONTENTS (Continued)

ii Spring Creek Mine TR1 EA

4.4 Air Quality ........................................................................................................................................4-5

4.5 Water Resources ..........................................................................................................................4-21

4.6 Alluvial Valley Floors .....................................................................................................................4-28

4.7 Wetlands (Aquatic Resources) ...................................................................................................4-28

4.8 Soil ....................................................................................................................................................4-29

4.9 Vegetation .......................................................................................................................................4-30

4.10 Wildlife ........................................................................................................................................4-30

4.11 Land Use and Recreation ........................................................................................................4-36

4.12 Cultural Resources ...................................................................................................................4-37

4.13 Visual Resources .......................................................................................................................4-38

4.14 Noise ............................................................................................................................................4-39

4.15 Transportation Facilities ..........................................................................................................4-40

4.16 Hazardous and Solid Waste ....................................................................................................4-42

4.17 Socioeconomics .........................................................................................................................4-43

4.18 Short Term Uses and Long Term Productivity ..................................................................4-44

4.19 Unavoidable Adverse Effects ..................................................................................................4-44

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

5.1 Public Comment Process ...............................................................................................................5-1

5.2 Preparers and Contributors .........................................................................................................5-1

5.3 Distribution of the EA ....................................................................................................................5-1

6.0 References ....................................................................................................................... 6-1

LIST OF TABLES

Table 1-1. Crosswalk of Resources Analyzed in the 2010 LBM EA1and in the 2020 

TR1 EA ...................................................................................................................................1-9

Table 2-1. Summary Comparison of Coal Production, Surface Disturbance, Mine Life, 

and Employees for the No Action Alternative and Proposed Action, as of 

December 31, 2018.............................................................................................................2-1

Table 3-1. PM10 Concentration Values (Annual Mean STP μg/m3) for the SCM .......................3-4

Table 3-2. PM10 Concentration Values (Annual High [24 Hour] STP μg/m3) for the 

SCM.........................................................................................................................................3-4

Table 3-3. Measured PM2.5 Concentrations1in Sheridan, Wyoming ............................................3-4

Table 3-4. Estimated Annual Mean STP PM2.5 Concentrations (μg/m3).......................................3-5

Table 3-5. Estimated Annual High 24-Hour STP PM2.5 Concentrations (μg/m3).......................3-5

Table 3-6. Measured NO2 Concentrations in Rosebud County, Montana.................................3-5

Table 3-7. Measured O3 Concentrations at AQS Monitoring Site1300870001 ........................3-7
TABLE OF CONTENTS (Continued)

Spring Creek Mine TR1 EA iii

Table 3-8. Measured SO2 Concentrations in Rosebud County, Montana ..................................3-7

Table 3-9. Measured Annual Hg Stack (Air) Emissions from Power Stations in Big 

Horn and Rosebud Counties (Pounds)...........................................................................3-8

Table 3-10. Measured Annual Pb Air Emissions (in Pounds) from Power Stations in Big 

Horn and Rosebud Counties (Pounds)...........................................................................3-8

Table 3-11. Estimated Annual PM10, PM2.5, SO2, NOX, Hg, and CO Contributions from 

Coal Combustion...............................................................................................................3-10

Table 3-12. Measured Hydrogen Ion (H+ as pH) Concentrations at Monitoring Site 

MT00.....................................................................................................................................3-10

Table 3-13. 2018 Greenhouse Gas Emissions from Large Facilities, by Sector.........................3-13

Table 3-14. Estimated Equivalent CO2 (CO2e) Emissions from Coal Mined at the SCM........3-14

Table 3-15. Peak GRSG Counts at Leks Within the Spring Creek Mine Annual

Monitoring Area During Spring, 2018 ...........................................................................3-22

Table 3-16. Destinations, Tonnages, and Distances for Coal Mined at the SCM in 2018.......3-26

Table 4-1. SCM Particulate Matter Dispersion Modeling Results.................................................4-6

Table 4-2. Estimated Annual PM10, PM2.5, SO2, NOX, Hg, and CO Contributions from 

Coal Combustion for 2014-2018 and 2020-2031, Compared to 2014 U.S. 

Total Emissions...................................................................................................................4-10

Table 4-3. Estimated Annual CO2e Emissions for the Proposed Action from Coal 

Mined at the SCM (2014-2018 Average and 2020-2031 Average) Under 

100-year and 20-year Time Horizons............................................................................4-12

Table 4-4. Trends in Global, U.S., Regional, and Local GHG Emissions and 

Contributing Factors.........................................................................................................4-14

Table 4-5. The Potential Climate Change Impacts in Montana and Big Horn County, 

Montana for Various Data Variables..............................................................................4-19

Table 4-6. Unavoidable Adverse Effects of the Proposed Action...............................................4-45

Table 5-1. OSMRE Personnel................................................................................................................5-1

Table 5-2. Third Party Contractor Personnel...................................................................................5-1

LIST OF FIGURES

Figure 3-1. Visibility in the Northern Cheyenne Indian Reservation Area – Site MT00 ..........3-9

Figure 3-2. Montana annual CO2e, in million metric tons.............................................................3-13

LIST OF MAPS

Map 1-1. General Location of the TR1 Tract .................................................................................1-2

Map 1-2. Configuration of the TR1 Tract and Coal Leases within the Spring Creek 

Mine Permit Boundary ........................................................................................................1-3
TABLE OF CONTENTS (Continued)

iv Spring Creek Mine TR1 EA

Map 3-1. Wind Rose and Air Quality and Meteorological Stations at the Spring 

Creek Coal Mine..................................................................................................................3-3

Map 3-2. Regional Air Quality Monitoring Sites.............................................................................3-6

Map 3-3. Active Groundwater Monitoring Locations at the Spring Creek Mine .................3-15

Map 3-4. Surface Drainages and Surface Water Monitoring Sites at the Spring Creek 

Mine.......................................................................................................................................3-17

Map 3-5. Wildlife Use Associated with the TR1 Tract within the Spring Creek Mine 

Area.......................................................................................................................................3-21

Map 4-1. Predicted Drawdown in the Anderson Dietz Aquifer...............................................4-22

Map 4-2. Predicted 10-Foot Drawdown in the D1, D1U, and D1L Aquifers........................4-23

Map 4-3. Predicted 10-Foot Drawdown in the D2 and D3 Aquifers......................................4-24

LIST OF APPENDICES

Appendix A Revisions/Errata, Public Scoping Documents, Public Review Comments Summary, 

Public Review Comments Log, and Notice of Availability Mailing Lists

Appendix B Calculations of Greenhouse Gas Emissions Calculations; PM10, PM2.5, SO2, NOx,

Hg, CO, and CO2 Contributions from Mining; and Emissions from Coal 

Combustion 

Appendix C 2018 4

th Quarter and Annual Spring Creek Mine Groundwater Monitoring 

Results

Appendix D Spring Creek Mine Observed Wildlife Species List and Special Status Species 

Affects Determinations Summary Tables

Appendix E Cultural Resource Management Inside SMP C1979012
Chapter 1- Purpose and Need

Spring Creek Mine TR1 EA 1-1

1.0 Purpose and Need

1.1 Introduction

Spring Creek Coal LLC (SCC) is seeking to modify its current federal mining plan to allow 

recovery of the additional federal coal associated with MTM-069782. This environmental 

assessment (EA) for the Spring Creek Mine (SCM) federal mining plan modification for a portion 

of federal coal lease MTM-069782 (TR1 Tract) has been prepared by the U.S. Department of the 

Interior (DOI)/Office of Surface Mining Reclamation and Enforcement (OSMRE), Western 

Region. OSMRE will prepare a mining plan decision document (MPDD) in support of its 

recommendation to the Assistant Secretary, Lands and Minerals Management (ASLM) regarding 

federal mining plan modifications (OSMRE 1999). The ASLM will decide whether the mining plan 

modification is approved, disapproved, or approved with conditions. Using criteria outlined in 

OSMRE’s Handbook for Implementing the National Environmental Policy Act (OSMRE 2019), the 

DOI’s Departmental Manual (DM) Part 516 (DOI 2004), the Council on Environmental Quality 

(CEQ) Regulations for Implementing the Procedural Provisions of the National Environmental 

Policy Act (40 Code of Federal Regulation [C.F.R.] Subparts 1500-1508), and the DOI’s 

regulations for implementation of the National Environmental Policy Act of 1969 (43 C.F.R. Part 

46), OSMRE determined that this EA could incorporate by reference analyses included in the EA

for Spring Creek Coal Lease Modification MTM-069782 and Amendment to Land Use Lease 

MTM-74913 (hereafter 2010 LBM EA [BLM 2010a]). The 2010 LBM EA evaluated impacts related 

to mining federal coal within the TR1 Tract. This approach is consistent with Secretarial Order 

3355, which is intended to streamline the National Environmental Policy Act (NEPA) process.

This EA review has been conducted in accordance with the NEPA and the CEQ regulations for

implementing NEPA (40 C.F.R. Parts 1500-1508); the DOI’s regulations for implementation of 

NEPA (43 C.F.R. Part 46); the DOI’s Departmental Manual Part 516; and OSMRE’s Directive 

REG-1, Handbook on Procedures for Implementing the National Environmental Policy Act 

(OSMRE 2019). Information gathered from federal, state, and local agencies, SCC publicly 

available literature, the 2020 Spring Creek Mine Cumulative Hydrologic Impacts Assessment, 

(hereafter 2020 CHIA [Montana Department of Environmental Quality/Water Quality Division 

2020]), and in-house OSMRE sources, such as the SCM Permit Application Package (PAP) for 

TR1 Major R, was used in the preparation of this EA.

1.2 Background

1.2.1 Site History

SCC, a wholly-owned subsidiary of Cloud Peak Energy Resources (CPE), operates the SCM, 

which is located in Big Horn County, Montana, approximately 32 miles north of Sheridan, 

Wyoming (map 1-1). Coal has been mined on a commercial scale at the SCM since 1979. 

Ownership of the surface and mineral estate within the permit boundary was thoroughly 

discussed in section 3.11 of the 2010 LBM EA and surface and mineral estate ownership has not 

changed since 2010. The SCM has recovered coal under eight distinct coal leases, as shown on 

map 1-2.
Chapter 1- Purpose and Need

1-2 Spring Creek Mine TR1 EA

Map 1-1. General Location of the TR1 Tract
Chapter 1- Purpose and Need

Spring Creek Mine TR1 EA 1-3

Map 1-2. Configuration of the TR1 Tract and Coal Leases within the Spring 

Creek Mine Permit Boundary
Chapter 1- Purpose and Need

1-4 Spring Creek Mine TR1 EA

As a result of an internal BLM administrative action, portions of federal coal leases MTM-069782 

and MTM-094378 were separated out to create two new federal coal leases; MTM-110692 and 

MTM-110693. Rather than adding additional coal reserves or area to the leases or the federal 

mining plan, this administrative action simply changed the federal coal lease identifying labels for 

reserves already included within the mining plan. Because this administrative action was approved

following the application for the federal mining plan modification, the application materials and 

Resource Recovery and Protection Plan (R2P2) referenced by this EA do not reflect the revised 

lease identifications. However, the revised lease configuration is presented on map 1-2.

The SCM is located in the Montana Powder River Basin (PRB) region, a coal basin that spans from 

northeast Wyoming to southeast Montana. The PRB produces 80 percent of the coal mined from 

federal government owned coal leases in the U.S. The region has also been heavily developed for 

oil and gas recovery, most recently for coal bed natural gas (CBNG) recovery. The entire TR1 

Tract is currently leased for surface coal mining. 

Coal is mined at the SCM using conventional surface-mining methods and shipped from an onsite 

railroad loading facility to electric utilities and industrial customers in the northwest, midwest, 

and southwest United States, and exported to Asian utility customers via the Westshore 

Terminal in British Columbia, Canada (SCC 2019). In 2018, approximately 67 percent of coal 

from the SCM was shipped to U.S. markets and approximately 33 percent were foreign 

shipments. The coal was transported by rail from the SCM to 13 power plants at a per-trip

average of 1,210 rail miles (weighted average based on distance and tons shipped). Coal was also 

transported by rail to one port for one-way overseas transport (4,300 nautical miles). The 

primary routes for rail transport are shown on map 1-3. 

The R2P2 for the SCM is sequenced to concurrently operate four mining pits. The BLM Montana 

State Office approved modifications to the R2P2 for the SCM on June 19, 2017. This sequencing 

is necessary to ensure proper blending of the coal to meet coal contract stipulations. It is also 

necessary to lessen the risk of interrupted coal delivery in case an emergency (i.e., pit flooding) 

disrupts operations in one of the pits. The mine also has specific bench lengths and bench 

orientations. These specific pit lengths, orientations, and other mine design factors are done to 

optimize the coal haul distances. This mine plan design has been approved by the BLM in the 

R2P2 and is needed to ensure maximum recovery of the coal resource. As explained in the R2P2,

interruptions to the mine plan sequence will disrupt these strategic decisions, resulting in illogical 

sequences, more overburden rehandle, longer haul distance, delayed reclamation, and lower coal 

recovery.

1.2.2 Project Background

In anticipation of needed additional coal reserves, SCC filed an application in 2007 with BLM to 

lease a tract of federal coal under leasing by modification regulations (also known as LBM

regulations) at 43 C.F.R. § 3432.0-3 and the provisions of the Energy Policy Act of 2005 

(Government Publishing Office [GPO] 1982 and U.S. Congress 2005, respectively). The tract was

applied for as a maintenance tract for the SCM to maintain operation at the mine’s current 

average annual level of production and was assigned case file number MTM-069782. BLM 

prepared the 2010 LBM EA to satisfy NEPA requirements for the LBM. The 2010 LBM EA 

analyzed the potential impacts associated with coal recovery and reclamation of the 498.1 acres 

of additional federal coal associated with MTM-069782, which would allow the SCM to continue 

producing coal at the current rate instead of ceasing production as recoverable coal reserves 

were nearly exhausted. OSMRE and the Montana Department of Environmental Quality (MDEQ)

were cooperating agencies on the 2010 LBM EA. Federal coal lease MTM-069782 as leased is

shown on map 1-2.
Chapter 1- Purpose and Need

Spring Creek Mine TR1 EA 1-5

Map 1-3. BNSF Rail Road Routes Used to Transport SCM Coal
Chapter 1- Purpose and Need

1-6 Spring Creek Mine TR1 EA

BLM’s Miles City Field Office issued a decision record (DR) on April 12, 2010, recommending 

modification of federal coal lease MTM-069782 to add approximately 498.1 acres of federal coal 

associated with the Proposed Action (BLM 2010a) and the lease of 50.8 Mt of mineable federal 

coal was effective July 1, 2010. It should be noted that, for the purposes of this evaluation, the 

original estimated amount of mineable coal within the tract has been revised upward to 56.4 Mt

mineable (53.6 Mt recoverable) based on the approved R2P2. In addition, the anticipated annual 

production rate evaluated in the 2010 LBM EA of 18 Mt, which was based on estimated 

production at that time, has been reduced to the 14.2 Mt evaluated in this EA. These changes are 

a result of reevaluation of coal quantities and market conditions. From 2014 through 2018, the 

annual coal recovery at the SCM ranged from 16.4 Mt in 2014 to 10.3 Mt in 2016, averaging 14.2 

Mtpy over that time period (SCC 2019). While the evaluated annual rate of 14.2 Mtpy is a 

reasonable analytical estimate given current coal demand and the recent annual production at the 

mine, SCC has the option of producing coal up to its annual limit under their current Montana 

Air Quality Permit (MAQP) #1120-12, which allows a maximum coal production of 30.0 Mtpy 

(MDEQ-Permitting and Compliance Division [PCD] 2014).

1.2.3 Statutory and Regulatory Background

For existing approved federal mining plans that are proposed to be modified, OSMRE prepares a 

MPDD, utilizing an appropriate NEPA analysis document. The ASLM reviews the MPDD and 

decides whether or not to approve the federal mining plan modification, and if approved, whether 

any conditions may be needed, pursuant to 30 C.F.R. Part 746. OSMRE’s recommendation 

regarding the evaluation of the federal mining plan modification will be based, at a minimum, on

1. the PAP, 

2. the R2P2,

3. information prepared in compliance with NEPA, including this EA,

4. documentation demonstrating compliance with the applicable requirements of 

federal laws, regulations, and executive orders other than NEPA,

5. comments and recommendations or concurrence of other federal agencies and 

the public,

6. findings, recommendations, and contractual commitments and requirements of 

BLM with respect to lease MTM-069782, the R2P2, and the Mineral Leasing Act 

of 1920 (MLA),

7. findings and recommendations of MDEQ with respect to the mine permit revision 

application and the Montana State SMCRA regulatory program,

8. the findings and recommendations of OSMRE with respect to the additional 

requirements of 30 C.F.R. Chapter VII, Subchapter D (30 C.F.R. Parts 740 to 746),

9. OSMRE’s obligations under MLA and DOI regulations to ensure that SCC achieves 

maximum economic recovery of the federal coal reserves in MTM-069782 (30 

U.S.C. § 201(a)(3)(C); 30 C.F.R. § 746.13(e); 43 C.F.R. § 3482.1(c)(7)), and

10. SCC’s obligations under the MLA, DOI regulations, and the terms of MTM-069782

to diligently develop the leased federal coal reserves and maintain continued 

operation (30 U.S.C. § 207(b)(1); 43 C.F.R. § 3480(a)(8),(12) and 

43 C.F.R. § 3483.1(a)(1)-(2)).

OSMRE’s recommendation is also guided by the following existing documents:

1. BLM’s 2010 leasing decision, which conveyed property and contract rights to SCC

through the issuance of MTM-069782; and
Chapter 1- Purpose and Need

Spring Creek Mine TR1 EA 1-7

2. MDEQ’s binding mining permit TR1 MR for SMP C1979012 and MAQP #1120-12, 

both of which established substantive operational standards for the development 

of the coal that is subject to the federal mine plan.

1.3 Purpose and Need

As described in 40 C.F.R. § 1502.13, the purpose and need statements briefly specify the purpose 

and need to which the agency is responding in proposing the alternatives including the Proposed 

Action.

1.3.1 Purpose

The purpose of the action is established by the MLA and the SMCRA, which requires the 

evaluation by OSMRE of SCM’s proposed mining plan modification before allowing surface mining 

and reclamation operations to develop the TR1 Tract associated with federal coal lease 

MTM-069782. OSMRE is the agency responsible for making a recommendation, supported by 

meeting all the requirements of the statutes and regulations listed in Section 1.4.1,to the ASLM 

to approve, disapprove, or approve with conditions the proposed mining plan modification. The 

ASLM will decide whether the mining plan modification is approved, disapproved, or approved 

with conditions.

1.3.2 Need

The need for this action is to provide SCC the opportunity to exercise its valid existing rights 

granted by the BLM under federal coal lease MTM-069782 to access and recover these federal 

coal reserves located in the TR1 Tract. ASLM approval of the federal mining plan modification is 

necessary to recover the reserves.

1.4 Regulatory Framework and Necessary Authorizations

1.4.1 Statutes and Regulations

The following key laws, as amended, establish the primary authorities, responsibilities, and 

requirements for developing federal coal resources:

1. MLA,

2. NEPA,

3. Mining and Minerals Policy Act of 1970 (MMPA),

4. Energy Policy Act of 2005,

5. Federal Coal Leasing Act Amendment, 1976 (FCLAA),

6. Federal Land Policy Management Act of 1976 (FLPMA),

7. SMCRA, 

8. Multiple-Use Sustained Yield Act of 1960,

9. Endangered Species Act of 1973 (ESA),

10. Clean Air Act, as amended (CAA),

11. Clean Water Act (CWA),

12. Safe Drinking Water Act, as amended (SDWA),

13. National Historic Preservation Act, as amended (NHPA),

14. American Indian Religious Freedom Act of 1978 (AIRFA), and

15. Migratory Bird Treaty Act of 1918, as amended (MBTA).

In addition, this EA follows guidance in OSMRE’s Handbook for Implementing the National 

Environmental Policy Act (OSMRE 2019) and DOI 516 DM (DOI 2004). A MPDD will be 

prepared and submitted to the ASLM for the considered federal mining plan modification.
Chapter 1- Purpose and Need

1-8 Spring Creek Mine TR1 EA

1.5 Outreach and Issues

Following a review of the 2010 LBM EA and the 2016 federal MPDD for SCM Federal lease 

MTM-94378 (OSMRE 2016a), OSMRE determined that further analyses were appropriate, based 

on newly available information and changes to the environmental consequences assessment of 

the Proposed Action that have occurred since 2010. Internal discussions within OSMRE identified 

a preliminary set of issues to be considered during the NEPA analysis. Substantive issues identified 

during the public scoping period (October 15 through November 14, 2015) were also considered 

during the document preparation. The public scoping comment letters are summarized in 

appendix A and the summarized issues and the number of comments received associated with 

each issue (in parentheses) include:

1. water quality (2),

2. air quality (2),

3. wildlife (2),

4. level of NEPA/ NEPA process (2),

5. climate change/global warming (2),

6. adequacy of permitting (1),

7. against mining (2) [the 4,213 form letters that were against mining were counted 

as one comment].

1.6 Crosswalk of Resource Areas

Table 1-1 identifies the location of resource discussions presented in the 2010 LBM EA and lists 

their location in this EA, where present. While all of the resources have been considered, not all 

of the resources have been brought forward for analysis in this EA. OSMRE determined than 

those resources and effects not brought forward for analysis had been sufficiently documented 

in the 2010 LBM EA DR and that new information would not affect the decision-making process. 

Information presented in the 2010 LBM EA that adequately described the affected environment 

for resources is incorporated by reference into this EA in their entirety and are not reiterated.

1.7 Public Involvement

On October 15, 2015, OSMRE posted an announcement of the EA on its Initiatives webpage 

(OSMRE 2016b). The announcement initiated a comment period that extended from October 

15 through November 14, 2015. OSMRE also published a notice of intent (NOI) to prepare this 

EA in both the Sheridan Press and Big Horn County News on October 15 and 29, 2015. Public 

outreach and Tribal consultation letters were also sent out to interested parties, stakeholders 

and tribes that could be affected by the project. OSMRE received written and e-mailed comments 

from 4,214 individuals. A form letter in favor of the SCM accounted for 4,213 comments. Public 

comments were reviewed and new substantive concerns were considered during the issues 

identification process. Lists of agencies, tribes, and individuals included on mailing lists and the

public scoping comment letters received are included in appendix A. OSMRE has determined 

that the 2015 public involvement was sufficient to identify issues of concern for the TR1 Tract. 

The substantive issues identified during public scoping were considered during preparation of this 

EA.
Chapter 1- Purpose and Need

Spring Creek Mine TR1 EA 1-9

Table 1-1. Crosswalk of Resources Analyzed in the 2010 LBM EA1and in the 2020 

TR1 EA

Resource

2010 LBM EA

Affected 

Environment

2010 LBM EA 

Environmental 

Consequences

2020 TR1 EA

Issues Revisited

2020 TR1 EA

Affected 

Environment 

2020 TR1 EA

Environmental 

Consequences

General Setting 3.1 4.1.1 Summary only 3.1 4.1

Topography and 

Physiography 3.2 4.1.1 Summary only 3.2 4.2

Geology, Minerals, 

and Paleontology

3.3

3.3.1

3.3.2

4.1.2 Summary only 3.3 4.3

Air Quality

3.4

3.4.1

3.4.2

3.4.3

4.1.3

Update AQ discussions 

to include new AQ 

information from annual

reports and AQ permit 

updates. Add GHG 

discussions

3.4 4.4

Water Resources

3.5

3.5.1

3.5.2

4.1.4

Update surface and 

groundwater and water

rights discussions. 

3.5

4.5

Alluvial Valley Floors 3.6 4.1.5 Summary only 3.6 4.6

Aquatic Resources

(Wetlands) 3.7 4.1.6 Summary only 3.7 4.7

Soils 3.8 4.1.7 Summary only 3.8 4.8

Vegetation 3.9 4.1.8 Summary only 3.9 4.9

Wildlife (Including 

Threatened and 

Endangered and 

Special Status 

Species)

3.10.1

3.10.2

3.10.3

3.10.4

3.10.5

3.10.6

3.10.7

Appendices A, B, & 

C

4.1.9

Update raptor nest 

locations from annual 

reports;

Update Greater sagegrouse discussions;

Update T&E and special 

status species 

discussions

3.10 4.10

Land Use and 

Recreation 3.11 4.1.10 Summary only 3.11 4.11

Cultural Resources 3.12

3.12.1 4.1.11

Update to discuss any 

new CR inventories, 

especially related to 

BLM stipulations

3.12 4.12

Visual Resources 3.13 4.1.12 Summary only 3.13 4.13

Noise 3.14 4.1.13 Updates related to rail 

and vessel traffic 3.14 4.14

Transportation 3.15 4.1.14 Updates related to rail 

and vessel traffic 3.15 4.15

Hazardous and Solid 

Waste 3.16 4.1.15 Summary only 3.16 4.16

Socioeconomics

3.17

3.17.1

3.17.2

3.17.3

3.17.4

3.17.5

3.17.6

4.1.16

Update Economics 

Discussions to Reflect 

Current Conditions

3.17 4.17

Greenhouse Gas 

Emissions 3.18 4.1.17

GHG discussions

Moved to sections 

3.4.1.5, 4.4.5, and 4.4.6

-- --

Short Term Uses and 

Long-Term 

Productivity

-- -- New to 2020 TR1 EA 3.18 4.18

Unavoidable Adverse 

Effects -- -- New to 2020 TR1 EA 3.19 4.19

Chapter 2 – Proposed Action and Alternatives

Spring Creek Mine TR1 EA 2-1

2.0 Proposed Action and Alternatives

Under the requirements of NEPA, an EA must evaluate the environmental impacts of a reasonable 

range of alternatives that meet the project’s purpose and need. The DOI’s NEPA implementing 

regulations define reasonable alternatives as those that are “technically and economically practical 

or feasible and meet the purpose and need of the proposed action” (43 C.F.R. § 46.420). This 

chapter describes the Proposed Action and the No Action Alternative considered and analyzed 

in detail in this EA. In addition, it identifies alternatives considered but eliminated from detailed 

analysis.

2.1 Description of the Alternatives

Because the 2010 LBM EA is incorporated by reference in this EA, the Proposed Action and No 

Action Alternative analyzed in this EA reflect the alternatives considered in the 2010 LBM EA. 

Section 2.1.3 includes alternatives considered but eliminated from detailed analysis. In addition, 

this EA also reflects updated resource-specific information collected since the publication of the 

2010 LBM EA. A description of the Proposed Action and the action alternatives analyzed by this 

EA are included in this section and summarized in table 2-1.

Table 2-1. Summary Comparison of Coal Production, Surface Disturbance, Mine 

Life, and Employees for the No Action Alternative and Proposed 

Action, as of December 31, 2018

Item No Action 

Alternative

Federal Mining Plan 

Approval of the Proposed 

Action

Remaining Mineable Federal Coal179.7 Mt 136.1 Mt 

(56.4 Mt added)

Remaining Recoverable Federal Coal175.7 Mt 129.3 Mt

(53.6 Mt added)

MDEQ Permit Area (From SMP C1979012) 9,220.0 acres

9,220.0 acres

(no change)

Currently Approved Federal Mine Plan Area 3,772.7 acres

4,270.8 acres

(498.1 acres added)

MDEQ Acres to Be Disturbed (From SMP C1979012) 6,134.0 acres

6,862.4 acres

(728.4 acres added)

Average Annual Coal Production 14.2 Mt 14.2 Mt

(no change)

LOM Year (From SMP C1979012) 2027 2031

(4 years added)

Average Number of Employees 281 281

(no change)

1 Approved in the 2016 MPDD

2.1.1 Proposed Action

The Proposed Action would modify the federal mining plan and authorize SCC to conduct coal 

mining on an additional 498.1 acres of federal coal to recover approximately an estimated 53.6 Mt 

of the 56.4 Mt of mineable coal. SCC projects that mining in the tract would begin in 2020 and,

using an annual production rate of 14.2 Mt, mining this coal would extend the mine’s life by about 

4 years, to 2031. The SCM’s current MAQP #1120-12 allows a maximum coal production of 30.0 

Mtpy (MDEQ-PCD 2014). Approximately 728.4 acres of disturbance would be added from the 

federal mining plan revision.

The TR1 Tract would be mined as an integral part of the SCM under the Proposed Action. 

Because the TR1 Tract would be an extension of the existing SCM, the facilities and infrastructure 
Chapter 2 – Proposed Action and Alternatives

2-2 Spring Creek Mine TR1 EA

would be the same as those identified in SMP C1979012 and in modifications to the BLM R2P2, 

which were approved June 19, 2017.

2.1.2 No Action Alternative

Under the No Action Alternative, the proposed mining plan modification would not be approved 

by the ASLM, and SCM would continue to operate under the currently approved federal mining 

plan. Under this alternative, OSMRE would not recommend approval or approval with conditions 

of the federal mining plan modification, and the ASLM would issue a decision based on the No 

Action Alternative.

If the No Action Alternative is selected, SCM would bypass the coal in the project area, resulting 

in 53.6 Mt of federal coal not being recovered and 728.4 acres of previously undisturbed ground 

not being disturbed. Under this alternative, the SCM would mine its remaining 75.7 Mt of 

recoverable federal coal reserves within the existing mine leases in approximately 5.3 years at an 

average production rate of approximately 14.2 Mtpy.

2.1.3 Alternatives Considered but Eliminated from Detailed Analysis

The following alternatives were considered but eliminated from detailed analysis. The discussions 

include reasons the alternatives were eliminated from detailed analysis.

2.1.3.1 Underground Mining Alternative

An alternative to require SCC to use underground mining methods to extract the coal was 

identified in public comments received during the outreach period, considered by OSMRE, and 

eliminated from detailed study because MDEQ has approved a surface mining permit for this 

project using surface mining techniques, and underground mining is inconsistent with the 

approved permit. The purpose and need for this EA is predicated upon review of a surface mining 

plan included as part of the MDEQ-approved surface mining permit. An Underground Mining 

Alternative would, thus, be inconsistent with the Purpose and Need for this action.

Also, as implied in the BLM Finding of No Significant Impact and Decision Record for 

Environmental Assessment for Spring Creek Coal Lease Modification (BLM 2010a), lease 

MTM-069782 is a surface reserve lease only. Therefore, the lease was purchased and held by the 

SCC with the clear understanding by all parties concerned that the lease would be mined by 

surface mining methods.

This alternative is also economically infeasible at current permitted production rates, and the 

economics of initiating an underground longwall mining operation in the SCM are not cost 

effective. The facilities and equipment needed for underground mining are different from surface 

mining. Because the infrastructure for underground mining is not in place at the SCM, new 

infrastructure for underground mining would need to be constructed. The capital expenditure to 

develop an underground mine would be prohibitive. In addition, all new surface facilities would 

need to be constructed, including, but not limited to, conveyors, coal stock piles, a wash plant, 

and maintenance and support facilities. In addition, all new underground mining equipment would 

need to be purchased such as, but not limited to, a long wall mining system, conveyor 

systems/drives/power stations, vehicles for transporting employees and supplies, several 

continuous miners, shuttle cars, large and small ventilation fans, and roof bolters.

In addition, approval by MDEQ of an application for a permit revision would be required to 

authorize underground mining. The process for SCC to design and engineer a new underground 

mine and for MDEQ to process a new permit application would take a number of years. These 

factors also result in this potential alternative being economically unreasonable.
Chapter 2 – Proposed Action and Alternatives

Spring Creek Mine TR1 EA 2-3

This alternative was not brought forward for detailed analysis because underground mining does 

not respond to the purpose and need for this action and the economic burden to shift to 

underground mining would be prohibitive.

2.1.3.2 Low or No Pollutant Emitting Equipment

Public comments suggested considering an alternative that required reduced air emissions at the 

mine by changing or modifying mining related equipment to equipment which would produce 

lower air emissions. The SCM is a relatively small contributor of the emissions related to engine 

combustion (primarily carbon dioxide [CO2] and oxides of nitrogen [NOX]) in the region.

The cost to make the switch to equipment powered by a different fuel (such as natural gas or 

solar powered equipment) for approximately 498.1 acres of federal coal would be cost prohibitive 

for the minimal benefit to the regional air quality. In addition, the use of natural gas powered 

engines in mining equipment is relatively new and some types of equipment would not be available 

for replacement with natural gas powered engines. The use of solar power to run large equipment 

has not been tested and is not considered technologically feasible at this time. Similarly, 

retrofitting existing equipment with additional emissions control devices would be expensive with 

limited effect on regional air emissions.

OSMRE has not brought forward this alternative for full analysis because requiring natural gas 

and solar powered engine technology and retrofitting existing equipment is not economically or 

technically feasible for all equipment at the SCM; and would likely have substantially similar effects 

to an alternative that is analyzed.

2.1.3.3 Air Quality Mitigation Alternatives

Some public comments suggested that OSMRE consider alternatives that mitigate air quality 

impacts, specifically by imposing more stringent emission limits at power plants fueled by the SCM 

and by requiring oil and gas operators in the region to reduce their emissions. These proposals 

are not alternatives being considered. The effects of coal combustion are analyzed in the 

Proposed Action as well as in the No Action Alternative because they are considered to be 

indirect effects. CEQ regulations at 40 C.F.R. § 1508.8 define “indirect effects” as those which 

are caused by the proposed action and are later in time or farther removed in distance but are 

still reasonably foreseeable. These indirect effects would occur as a result of burning the coal that 

is mined. The analysis concluded there would not be significant impacts to air resources under 

the Proposed Action and no mitigation was recommended. Any mitigation measure proposed by 

OSMRE imposing more stringent emission limits at generating stations and upon non-coal 

operators is beyond OSMRE’s authority and its implementation would be highly remote and 

speculative.

2.1.3.4 Reduce Coal Mining Rates and Numbers of Trains 

Under this alternative, SCM would reduce their coal mining production rates, resulting in the 

need for fewer coal trains. The alternative would increase the duration of mining and train traffic. 

It would also delay reclamation, potentially increasing impacts associated with mining in the area. 

In addition, SCC is not proposing to increase the number of coal shipments. Production rates 

would remain the same in both the No Action and the Proposed Action.

2.1.3.5 Investments in Clean Energy

OSMRE received a public comment requesting that consideration of an alternative to replace coal 

mining with “investments in clean energy.” This alternative was not carried forward for further 

analysis because it does not meet the purpose of the project (section 1.3.1), which is to review 
Chapter 2 – Proposed Action and Alternatives

2-4 Spring Creek Mine TR1 EA

and make a decision on SCM’s proposed mining plan modification before allowing surface mining 

and reclamation operations to develop the TR1 Tract associated with federal coal lease 

MTM-069782. 

2.2 Existing Conditions (Conditions Common to the Proposed Action 

and the No Action Alternative)

The 2010 LBM EA presented a thorough description of the existing conditions at the SCM to 

support the analysis presented therein. The following summary of updated existing condition, 

including ongoing permitted mining operations, are the most notable changes since the 2010 LBM 

EA was prepared. This update is provided to support the evaluation of potential impacts 

contained in chapter 4 of this EA.

Mining and reclamation activities have continued as approved by SMP C1979012 since the 2010

LBM EA was prepared and the modification to federal coal lease MTM-069782 was issued. The 

federal mining plan approval associated with the modification to coal lease MTM-069782 would 

allow mining of an additional 498.1 acres containing approximately 56.4 Mt of mineable federal 

coal. Operations at the SCM are conducted in accordance with applicable laws and regulations 

including SMCRA, MDEQ rules and regulations, and the MDEQ-approved PAP. The PAP, 

including approved revisions, provides the most complete descriptions of mining, environmental 

protection measures, and reclamation activities within the project area for the LOM and, as such, 

is used and referenced for the purpose of this EA. 

SCC currently employs 281 people at the SCM. From 2014 through 2018, SCC recovered 

approximately 70.9 Mt of coal from all permitted operations, at an average rate of 14.2 Mtpy 

(SCC 2019). Approximately 45 percent of the remaining federal coal within the approved SCM 

permit boundary is within MTM-069782 (SCC 2019). Approximately 75.7 Mt of federal was 

available for recovery after January 1, 2019, excluding the 53.6 Mt of recoverable federal coal 

identified in the Proposed Action. SCC continues to use conventional surface-coal mining 

techniques described in section 2.1.1.

2.2.1 Current Bonding and Bond Release Status

SMCRA provides that, as a prerequisite for obtaining or modifying a coal mining permit, 

permittees must post a reclamation bond to ensure that the regulatory authority will have 

sufficient funds to reclaim the site if the permittee fails to complete obligations set forth in the 

approved reclamation plan (OSMRE 2015). SCC updates the SCM reclamation bond annually 

through a process that requires MDEQ review and approval. The most recent bond was approved 

by MDEQ in May 2019 in the amount of $108,850,000 (SCC 2019). The mine’s reclamation bond 

is currently valid and will continue to be updated and approved by MDEQ on an annual basis.

There are four phases of bond release that Montana mine operators may request for the release

of a performance bond or monetary deposit regarding areas disturbed by coal removal. As 

outlined in Administrative Rule of Montana (ARM) 17.24.1116 (Bonding: Criteria and Schedule 

for Release of Bond [Montana Secretary of State 2015]), the four bond release phases for lands 

disturbed by coal mining are:

Phase I – when the permittee completes the backfilling, regrading, and drainage control 

of a bonded area,

Phase II – when the permittee has completed soil replacement and spoil and soil tillage, 

and vegetation is established in accordance with the approved reclamation plan,

Phase III – when the revegetation criteria applicable to and consistent with the 

approved postmining land use is met, and
Chapter 2 – Proposed Action and Alternatives

Spring Creek Mine TR1 EA 2-5

Phase IV – the remaining portion of the bond may be released after the permittee has 

successfully completed all surface coal mining and reclamation activities and all 

disturbed lands within any designated drainage basin have been reclaimed in 

accordance with the Phase I, II, and III requirements.

The acres of reclamation at the SCM from 2014 through 2018, by bond release phase, are shown 

in table 2-2.

Table 2-2. Total Mine Disturbance/Reclamation/Bond Release Acres

Year Total 

Disturbance

Facility 

Disturbance

Active 

Mining 

Area

Available 

for 

Seeding

Soiled 

& 

Seeded

Phase 

I

Phase 

II

Phase 

III

Phase 

IV

2014 4,371.1 996.8 2,171.5 1,202.8 1,173.5 982.0 622.2 0.0 0.0 

Ratio of total -- 23% 50% 28% 27% 22% 14% 0% 0%

2015 4,626.8 1,074.3 2,296.6 1,255.9 1,213.3 1,042.0 780.2 407.0 0.0

Ratio of total -- 23% 50% 27% 26% 23% 17% 9% 0%

2016 4,753.0 1,057.0 2,383.0

0

1,313.0 1,257.0 1,207.0 935.0 407.0 0.0

Ratio of total -- 22% 50% 28% 26% 25% 20% 9% 0%

2017 4,879.0 1,086.0 2,455.0 1,338.0 1,319.0 1,283.8 1,017.0 407.0 0.0

Ratio of total 22.3% 50.3% 27.4% 27.0% 26.3% 20.8% 8.3% 0%

2018 4,947.3 995.82 2,543.3 1,408.3 1,340.3 1,310.8 1,017.0 407.0 0.0

Ratio of total -- 20.1% 51.4% 28.5% 27.1% 26.5% 20.6% 8.2% 0%

Source: 2014 through 2018 Annual Mining Reports for the SCM for SMP C1979012. Total disturbance includes the Facility Disturbance, Active 

Mining Area, and the area Available for Seeding

There is a difference between lands that are in various stages of reclamation and those that have 

been reclaimed and released from final bonding requirements. Final bond release on reclaimed 

lands indicates that the reclamation meeting permit standards has been in place in accordance 

with permit standards for at least 10 years and that an application for final bond release was 

submitted to the MDEQ.

The standard for determining if mines are meeting their contemporaneous reclamation 

obligations is determined by compliance with permit commitments. This evaluation is conducted 

annually by OSMRE and, according to the 2018 Annual Evaluation Report for the Regulatory 

Program, all Montana coal mines evaluated in the report were found to be in compliance within 

the 2015 evaluation year (OSMRE 2018).

Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-1

3.0 Affected Environment

This chapter discusses the existing conditions of the physical, biological, cultural, and human 

resources that could be affected by implementation of the alternatives described in chapter 2. 

The determination of adequacy of the description of baseline conditions in the 2010 LBM EA was 

made if conditions have not substantively changed, no new data are available, the resource 

conditions have only been minimally affected as a result of current mining operations, and/or 

further presentation of information would not affect the decision-making process. Baseline 

information presented in the 2010 LBM EA that has not substantively changed is incorporated by 

reference. Updated information pertaining to the baseline data is presented in this chapter when 

applicable. 

3.1 General Setting

The general setting of the TR1 Tract is described in section 3.1 of the 2010 LBM EA. The tract is 

located in the PRB, which has a semi-arid, high plains environment with relatively large seasonal 

and diurnal variations in temperature and seasonal variation in precipitation.

3.2 Topography and Physiography

Topography and physiography of the TR1 Tract are described in section 3.2 of the 2010 LBM EA. 

The SCM is physiographically part of the unglaciated Missouri Plateau section of the Great Plains 

Province (Fenneman 1931). This part of the Great Plains Province is characterized by broad 

plateaus that are dissected by incised stream valleys. In the western portion, the plateaus merge 

with the PRB and other broad regional downfolds. These basins are separated by major 

mountainous uplifts. The SCM is located near the northwest limb of the structural basin lying in 

the Tongue River Valley.

3.3 Geology, Minerals, and Paleontology

General geology and coal resources are described in section 3.3.1 of the 2010 LBM EA. The SCM

area contains the following stratigraphic units or layers (in descending order from the surface): 

Quaternary (most recent) deposits, the Eocene-age Wasatch Formation, and the Paleocene-age

Fort Union Formation. The targeted coal seam lies within the Anderson-Dietz (A/D) coal seam, 

which is the uppermost unit of the Tongue River Member of the Fort Union Formation. Within 

the tract, the A/D coal seam thickness ranges between 70 and 85 feet. The A/D sub-bituminous 

coal seam is of high quality having low sulfur content and high British thermal units (Btu) values 

for the Great Plains. 

The discussions included in section 3.3.2 of the 2010 LBM EA provide details regarding the 

description of the minerals and paleontological resources. These details have not changed. No 

significant or unique paleontological resource localities have been documented on federal lands 

in the tract.

3.4 Air Quality and Climate Change

Air Quality regulations applicable to surface coal mining may include the National Ambient Air 

Quality Standards (NAAQS), Montana Ambient Air Quality Standards (MAAQS), and Prevention 

of Significant Deterioration (PSD). These regulatory programs are described in section 3.4.1 of 

the 2010 LBM EA. Additional air quality regulations applicable to surface coal mining include the 
Chapter 3 – Affected Environment

3-2 Spring Creek Mine TR1 EA

New Source Performance Standards (Section 111 of the CAA), and the Federal Operating Permit 

Program (Title V of the CAA).

Air quality information specific to the SCM is included in SCC’s MAQP #1120-12 (MDEQ-PCD 

2014). Section 3.4 of the 2010 LBM EA includes detailed discussions of air quality issues relating 

to the leasing and mining of coal related to the TR1 Tract. The analysis presented herein serves 

to summarize attainment/nonattainment areas discussions; update discussions with recent air 

quality monitoring findings; summarize revised air quality modeling results; and update discussions 

on carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), particulate 

matter (PM10 and PM2.5), lead (Pb), hydrogen sulfide (H2S), and hazardous air pollutants (HAPs) 

(specifically mercury [Hg]).

Since the tract is near the border of Montana and Wyoming, the attainment status of nearby 

areas in both states is considered. The TR1 Tract is in an area that is designated an attainment 

area for all pollutants (EPA 2018a). However, the town of Sheridan, Wyoming, located about 

32 miles south of the project area, is in maintenance status for PM10 (in the process of redesignating to attainment by continuing to show compliance with the NAAQS after having initially 

been in nonattainment). The town of Lame Deer, Montana, located about 40 miles north, is a 

non-attainment area for PM10. The town of Laurel, Montana, located about 90 miles northwest 

of the project area is a non-attainment area for SO2. The city of Billings, Montana, located about 

90 miles northwest of the project area, is in maintenance status for CO2 and SO2. None of these 

cities/towns are in line with prevailing winds (see map 3-1 for prevailing wind directions). 

3.4.1 Existing SCM Air Quality Summary

Baseline air quality data for the surface facilities area for the SCM are found in the section 3.4 of 

the 2010 LBM EA. The following discussions include updated (2014-2018) air quality monitoring 

results.

3.4.1.1 Air Quality-Particulate Matter

Based on SCC’s history of relatively low ambient monitoring readings and MDEQ’s confidence in 

current permit conditions, MDEQ removed the requirement for SCC to sample for PM10 in 

September 2009. SCC has voluntarily chosen to continue the PM10 sampling program. These data 

are used internally and not submitted to MDEQ, per MDEQ’s request. PM2.5 monitoring at the 

SCM is not required by MDEQ and is not conducted at this time.

Current, voluntary air monitoring consists of four samplers at three sites that monitor 

concentrations of PM10 and a meteorological site (map 3-1). Air quality monitoring sites C and D 

were relocated in 2010 to sites C2 and D2, respectively, to account for the progression of mining 

operations.

Tables 3-1 and 3-2 list the annual mean and high PM10 concentrations for the SCM. The average 

annual mean PM10 concentration from 2014-2018 ranged between 10.3 and 33.2 μg/m3(about 

21 percent to 66 percent of the annual MAAQS of 50 μg/m3). The annual high 24-hour PM10

values ranged between 24.6 and 110.8 μg/m3, or about 16 to 74 percent of the MDEQ-Air 

Resources Management Bureau (ARMB) 24-hour standard of 150 μg/m3. 
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-3

Map 3-1. Wind Rose and Air Quality and Meteorological Stations at the Spring 

Creek Coal Mine
Chapter 3 – Affected Environment

3-4 Spring Creek Mine TR1 EA

Table 3-1. PM10 Concentration Values (Annual Mean STP μg/m3) for the SCM

Site Name1 2014 2015 2016 2017 2018

A PM10 26.9 26.6 14.1 24.2 25.1

B PM10 26.9 27.3 13.6 24.2 26.2

C2 PM10 21.7 33.2 16.3 27.3 23.5

D2 PM10 18.0 16.6 10.3 16.5 15.7

1

See map 3-1 for site locations

Source: SCM Ambient Air Quality Monitoring Network 2018 2018 4th Quarter and Annual Report 2018 (IML 2018)

Table 3-2. PM10 Concentration Values (Annual High [24 Hour] STP μg/m3) for 

the SCM

Site Name1 2014 2015 2016 2017 2018

A PM10 65.1 75.2 31.9 60.3 60.8

B PM10 68.9 79.5 33.2 54.0 78.4

C2 PM10 39.0 94.2 43.3 110.8 68.0

D2 PM10 100.8 51.5 24.6 50.0 44.2

1

See map 3-1 for site locations

Source: SCM Ambient Air Quality Monitoring Network 4th Quarter and Annual Report (IML 2018)

Since PM2.5 monitoring is not required by MDEQ, data were not gathered onsite. Therefore, data 

from one PM2.5 monitor located in Sheridan Wyoming were used to estimate PM2.5 emissions at 

SCM (table 3-3). Regional monitoring demonstrated that ambient concentrations of PM2.5, as 

determined by the 98th Percentile 24-hour standard and annual average values, generally were 

within established 24-hour (35 μg/m3) and annual (12 μg/m3) standards. One exceedance was 

noted at the site in 2017.

Table 3-3. Measured PM2.5 Concentrations1in Sheridan, Wyoming

Site ID Year 24 hour (μg/m3) Annual (μg/m3)

2014 14 4.4

18 5.4

2015 3325.92

Meadowlark Elementary 18 5.2

(560331003) 2016 16 4.9

18 4.5

2017 22 6.6*

40 6.4*

2018 17 5.0

13 5.1

1 The 24-hour standard is met when the 98th percentile 24-hour concentration, as determined by Appendix N of 40 C.F.R. Part 50 is less 

than or equal to 35 micrograms per cubic meter. The annual standard is met when the arithmetic mean concentration, as determined by 

Appendix N of 40 C.F.R. Part 50 is less than or equal to 12 μg/m3. Bold test indicates an exceedance.

2

Included an exceptional event

* The mean does not satisfy minimum data completeness criteria

Source: EPA 2019a

To further evaluate potential PM2.5 emissions at the SCM, PM10 monitoring data from the SCM 

were used to estimate PM2.5 ambient concentrations by applying a 0.2 factor, as determined by 

Pace (2005). The estimated annual mean and maximum 24-hour PM2.5 values are presented in 

tables 3-4 and 3-5, respectively. The estimated PM2.5 concentrations were below the prescribed 

24-hour NAAQS (35 μg/m3) and the annual NAAQS (12 μg/m3). These estimates are supported 

by the regional PM2.5 data presented in table 3-3.
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-5

Table 3-4. Estimated Annual Mean STP PM2.5 Concentrations (μg/m3)

Site Name1 2014 2015 2016 2017 2018

A 5.4 5.3 2.8 4.8 5.0

B 5.4 5.5 2.7 4.8 5.2

C2 4.3 6.6 3.3 5.5 4.7

D2 3.6 3.3 2.1 3.3 3.1

1

See map 3-1 for site locations

Table 3-5. Estimated Annual High 24-Hour STP PM2.5 Concentrations (μg/m3) 

Site Name1 2014 2015 2016 2017 2018

A 13.0 15.0 6.4 12.1 12.2

B 13.8 15.9 6.6 10.8 15.7

C2 7.8 18.8 8.7 22.2 13.6

D2 20.2 10.3 4.9 10.0 8.8

1

See map 3-1 for site locations

3.4.1.2 Emissions of Nitrogen Dioxide (NO2), Ozone (O3), Sulfur Dioxide (SO2), 

Mercury (Hg), Lead (Pb), and Carbon Monoxide (CO)

NO2 concentrations (98th percentile, 1 hour) are currently being monitored in Rosebud County 

at one air quality system (AQS) monitoring site near Birney (table 3-6). NO2 concentrations 

were also monitored through 2017 at three other AQS monitoring sites near the town of Lame

Deer (table 3-6). These monitoring sites are the closest to the SCM, between 28 and 44 miles 

(map 3-2). All monitored NO2 values were below the MDEQ-ARMB and NAAQS 1-hour 

standard (100 ppb) and annual standard (53 ppb).

Table 3-6. Measured NO2 Concentrations in Rosebud County, Montana

AQS

Site ID1 Sampler ID 2014 2015 2016 2017 2018

300870001 3 Miles North of Birney 1 hour 8 5 6 13 7

Annual 0.68 0.43 0.48 2.89 1.48

300870760 Morningstar 1 hour 54 18 11 12 --

Annual 2.96 1.93 1.78 0.57 --

300870761 Garfield Peak 1 hour 10 75 49 17 --

Annual 1.19 1.11* 1.51 0.48 --

300870762 Badger Peak 1 hour 10 10 13 9 --

Annual 1.71 0.91 1.47 0.54 --

1

See map 3-2 for site locations

-- Indicates the monitoring site data were not available, as of 8/23/19.

Source: EPA 2019a
Chapter 3 – Affected Environment

3-6 Spring Creek Mine TR1 EA

Map 3-2. Regional Air Quality Monitoring Sites
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-7

O3 monitoring is not required at the SCM but 2014 through 2018 concentrations are available

from AQS Site 300870001, which is the closest Montana monitoring site located approximately 

28 miles northeast of the tract (map 3-2). As shown in table 3-7, the 8-hour O3 values were 

below the NAAQS 8-hour standard of 0.070 ppm and the 1-hour O3 values were below the 

MDEQ-ARMB 1-hour standard of 0.10 ppm.

Table 3-7. Measured O3 Concentrations at AQS Monitoring Site1300870001

Parameter Measure 2014 2015 2016 2017 2018

MDEQ-ARMB 1 hour (ppm) 0.066 0.065 0.067 0.070 0.069

MDEQ-ARMB 1 hour (μg/m3) 139 137 142 148 146

NAAQS 8 hour (ppm) 0.055 0.056 0.057 0.059 0.059

NAAQS 8 hour (μg/m3) 116 118 120 125 125

Days maximum exceeded* 0 0 0 0 0

1

See map 3-2 for site location

* The standard is attained when the expected number of days per calendar year with maximum hourly average concentrations above 0.12 

parts per million (254 μg/m3) is equal to or less than 1, as determined by Appendix H of 40 C.F.R. Part 50.

Source: EPA 2019a

SO2 monitoring data were available from three sites in Rosebud County. No sites in Big Horn 

County monitor for SO2. As presented in table 3-8, SO2 data collected at the three sites were 

below the 1-hour MAAQS (0.50 ppm) 99th percentile concentrations. Data collected in 2015 

from the Garfield Peak site show that SO2 1-hour concentrations exceeded the NAAQS (0.075 

ppm) standard. High SO2 values were recorded in 2015 during a 3-day period, between June 3 

and June 5. Excluding this 3-day period, the 1-hour values averaged 0.001 ppm (EPA 2019a). The 

24-hour 1st maximum SO2 data collected at the three sites were also below the MAAQS (0.100 

ppm) concentrations (there is no NAAQS 24-hour standard). Therefore, it is likely that ambient 

air quality within the vicinity of the proposed action is currently in compliance with the SO2

MAAQS and NAAQS.

Table 3-8. Measured SO2 Concentrations in Rosebud County, Montana

AQS Site ID Sampler ID 2014 2015 2016 2017 2018

300870760 Morningstar 1 hour 0.008 0.009 0.008 0.009 --

24 hour 0.005 0.002 0.003 0.003 --

300870761 Garfield Peak 1 hour 0.008 0.215* 0.007 0.008 --

24 hour 0.004 0.020 0.005 0.006 --

300870762 Badger Peak 1 hour 0.007 0.011 0.006 0.006 --

24 hour 0.003 0.013 0.002 0.002 --

* The high 99th percentile 1-hour value was recorded during a 3-day period from June 3 through June 5, where maximums 1-hour 

concentrations ranged between 0.269 ppm and 0.191 ppm. 

-- No data for Rosebud County.

Source: EPA 2019a

Annual Hg (a HAP), Pb (a criteria pollutant), and CO (an indirect greenhouse gas [GHG])

monitoring values are not collected specifically for the SCM. For a general discussion on Hg 

emissions, Hg air emissions (stack plus fugitive) for 2013 through 2017 (2018 data are not 

available) from three coal-fired power plants and one coal mine in Big Horn and Rosebud counties 

were evaluated (table 3-9). 
Chapter 3 – Affected Environment

3-8 Spring Creek Mine TR1 EA

Table 3-9. Measured Annual Hg Stack (Air) Emissions from Power Stations in 

Big Horn and Rosebud Counties (Pounds)

AQS Site ID 2013 2014 2015 2016 2017

Colstrip Energy LP Rosebud Power Plant 110041886144

Total emissions 1.57 2.65 1.4 1.4 0.9

Stack (air) emissions 1.57 2.65 1.4 1.4 0.9

Percent Emitted to air 100.0 100.0 100.0 100.0 100.0

Colstrip Steam Electric Station 110041982520

Total emissions 1,278.0 1,244.0 1,175.4 1,316.7 1,433.4

Stack (air) emissions 110.0 110.0 120.0 130.0 140.0

Percent emitted to air 8.6 8.8 10.2 9.9 9.8

Hardin Generating Station 110038363623

Total emissions 22.9 16.0 0.1 24.4 18.0

Stack (air) emissions 5.7 4.3 0.1 5.7 3.7

Percent Emitted to air 24.9 26.9 100.0 23.4 20.6

Decker Coal Company

Total emissions 0.15 0.11 0.007 0.006 0.006

Stack (air) emissions 0.002 0.002 0.002 0.002 0.002

Percent Emitted to air 1.3 1.8 28.6 33.3 33.3

Total emissions from Four Sources

Total emissions 1,302.6 1,262.8 1,176.9 1,342.5 1,452.3

Stack (air) emissions 117.3 117.0 121.5 137.1 144.6

Percent Emitted to air 9.0% 9.3% 10.3% 10.2% 10.0%

Source: EPA 2019b

Annual Pb monitoring values are not collected at the SCM. Table 3-10 shows the Pb emissions 

from power stations in Big Horn and Rosebud counties for 2013 through 2017 (2018 data are 

not available). A direct comparison between the monitored values at the power plants/mines and 

NAAQS and MAAQS is not possible since the monitored values were presented in pounds, 

rather than the NAAQS and MAAQS units (μg/m3).

Table 3-10. Measured Annual Pb Air Emissions (in Pounds) from Power Stations 

in Big Horn and Rosebud Counties (Pounds)

AQS Site ID 2013 2014 2015 2016 2017

Colstrip Energy LP Rosebud Power Plant 110041886144

Total emissions 357.1 249.4 743.2 145.2 518.7

Stack (air) emissions 117.4 111.8 112.6 114.9 67.8

Percent emitted to air 32.9% 44.8% 15.2% 79.1% 13.1%

Colstrip Steam Electric Station 110041982520

Total emissions 78,379.0 86,936.5 93,358.0 97,979.0 91,612.0

Stack (air) emissions 680.0 750.0 800.0 730.0 730.0

Percent emitted to air 0.9% 0.9% 0.9% 0.7% 0.8%

Hardin Generating Station 110038363623

Total emissions 2,643.8 3,058.6 2,338.2 1,550.0 1,281.5

Stack (air) emissions 191.6 206.5 151.9 103.0 39.5

Percent emitted to air 7.2% 6.8% 6.5% 6.6% 3.1%

Decker Coal Company

Total emissions 17.4 20 20 2.65 3.3

Stack (air) emissions 0.0 0.0 0.0 0.05 0.05

Percent emitted to air 0.0% 0.0% 0.0% 1.9% 1.5%

Total emissions from Four Sources

Total emissions 81,397.3 90,264.5 96,459.4 99,676.9 93,415.5

Stack (air) emissions 989.0 1068.3 1064.5 948.0 837.4

Percent emitted to air 1.2% 1.2% 1.1% 1.0% 0.9%

Source: EPA 2019b
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-9

3.4.1.3 Air Quality Related Values (AQRVs)

AQRVs as related to the TR1 Tract were discussed in sections 3.4.5 and 3.4.6 of the 2010 LBM 

EA. Updated information regarding AQRVs is included below. AQRVs are evaluated by the land 

management agency responsible for a Class I area, according to the agency’s level of acceptable 

change (LAC). These AQRVs include potential air pollutant effects on visibility and the 

acidification of lakes and streams. The AQRVs, and the associated LAC, are applied to PSD Class I 

and sensitive Class II areas and are the land management agency’s policy and are not legally 

enforceable as a standard. MDEQ MAAQS do include a standard for visibility. Class I areas are 

afforded specific AQRV protection under the CAA. The Class I designation allows very little 

deterioration of air quality. The AQRVs associated with this action include visibility and 

acidification of lakes. The nearest Class I area is located approximately 19 miles north of the tract 

at the Northern Cheyenne Indian Reservation.

3.4.1.3.1 Visibility

In accordance with ARM 17.8.818, the state of Montana does not require mines to evaluate 

visibility impacts on Class I areas (MDEQ-PCD 2014). Because MDEQ has determined that the 

SCM is not a major stationary source and because the SCM is not required by MDEQ to monitor 

visibility, a direct comparison to MAAQS standards is not possible. The current visibility 

discussions have been inferred from the currently permitted mining activities related to the 

existing coal leases at the SCM. Visibility can be defined as the distance one can see and the ability 

to perceive color, contrast, and detail. Fine particulates (PM2.5) are the main cause of visibility 

impairment. Visibility impairment is expressed in terms of deciview (dv). The dv index was 

developed as a linear perceived visual change (Pitchford and Malm 1994) and is the unit of 

measure used in the EPA’s Regional Haze Rule to achieve the National Visibility Goal. A change 

in visibility of 1.0 dv represents a “just noticeable change” by an average person under most 

circumstances. Increasing dv values represent proportionately larger perceived visibility 

impairment. Figure 3-1 shows annual averages for the 20 percent best and worst visibility days 

at Northern Cheyenne Indian Reservation monitoring site (the nearest PSD Class I area, see 

map 3-2) for 2003 through 2018 (Interagency Monitoring of Protected Environments

[IMPROVE] 2019). Increasing dv values represent proportionately larger perceived visibility 

impairment (BLM 2003). The long-term trend in visibility at the Northern Cheyenne Indian 

Reservation appears to be relatively stable, if not improving slightly.

Figure 3-1. Visibility in the Northern Cheyenne Indian Reservation Area – Site

MT00

0

5

10

15

20

25

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

Visibility (dv)

Year

Haziest Clearest Linear (Haziest) Linear (Clearest)
Chapter 3 – Affected Environment

3-10 Spring Creek Mine TR1 EA

3.4.1.3.2 AQRVs Related to Coal Combustion

Emissions that affect air quality also result from combustion of fossil fuels. Table 3-11 presents 

the estimated PM10, PM2.5, SO2, NOX, Hg, and CO emissions estimates for combustion of coal 

mined at the SCM.

Table 3-11. Estimated Annual PM10, PM2.5, SO2, NOX, Hg, and CO Contributions 

from Coal Combustion

Source 2014 2015 2016 2017 2018

Tons of Coal 

Recovered

17.3 17.0 10.3 12.7 13.6

PM10 (tons) 3,872.9 3,797.5 2,293.4 2,846.4 3,033.1

PM2.5 (tons) 1,181.2 1,158.2 699.5 868.1 925.1

SO2 Emissions (tons) 71,421.0 70,030.0 42,293.5 52,490.2 55,934.1

NOX Emissions (tons) 27,597.2 27,059.7 16,342.3 20,282.3 21,613.0

Hg Emissions (tons) 0.28 0.27 0.16 0.20 0.22

CO Emissions (tons) 26.5 26.0 15.7 19.5 20.8

Source: WWC Engineering (WWC) completed the calculations, which are provided in appendix B

3.4.1.3.3 Acidification of Lakes

Acid deposition causes acidification of lakes and streams, which can have direct impacts on aquatic 

habitats and contribute to the damage of trees at high elevation and many sensitive forest soils. 

Acid rain is measured as acidity and alkalinity using a pH for which 7.0 is neutral. The lower a 

substances pH, the more acidic it is. Normal rain has a pH of about 5.6 (EPA 2019c). The National 

Atmospheric Deposition Program (NADP) monitors precipitation chemistry at various sites 

around the U.S. The nearest site to the tract is Site MT00 (map 3-2). Table 3-12 provides the 

measured hydrogen ion concentrations for the years 2014 through 2018. The trend in pH at 

monitoring site MT00 appears to be relatively stable.

Table 3-12. Measured Hydrogen Ion (H+ as pH) Concentrations at Monitoring Site 

MT00

Parameter 2014 2015 2016 2017 2018

pH 5.4 5.6 5.5 5.5 5.7

Source: NADP 2019

3.4.1.4 Climate Change

Climate in the SCM area is generally characterized as semi-arid, or a region where the potential 

evapotranspiration exceeds the precipitation, but not by an extreme margin (Peel, et al. 2007).

The nearest location for recorded long-term climate data is the Sheridan Field Station, Wyoming 

(Station ID 488160), which provided information for the period of record of 1920 to 2019. The 

station is approximately 18 miles south of the SCM. The average annual temperature during the 

period of record was 44.5 degrees Fahrenheit (°F), while the average annual maximum and 

minimum temperatures ranged from 59.1 to 29.9 °F, respectively. For the period of record, 

average annual total precipitation and total snowfall were reported to be 15.1 inches and 43.7

inches, respectively. The heaviest precipitation generally occurred between April and June with 

most snowfall generally occurred in March (Western Regional Climate Center 2020). According 

to wind data provided in the SCM 2018 ambient air monitoring network report, prevailing winds 

in 2018 were from the northwest, with maximum winds greater than 30 miles per hour (SCC 

2018a). 
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-11

Global warming refers to the ongoing rise in global average temperature near the Earth’s surface. 

It is caused mostly by increasing concentrations of GHGs (primarily CO2, methane, nitrous oxide 

[N2O], and fluorinated gases) in the atmosphere, and it is changing global climate patterns. 

Climate change refers to any significant change in the measures of climate (e.g., temperature, 

precipitation, and wind patterns) lasting for an extended period of time (EPA 2017a).

The Global Change Research Act of 1990 mandates that the U.S. Global Change Research 

Program (USGCRP) deliver a report to Congress and the president every 4 years that analyzes 

the effects of global climate change on the natural environment and other systems, as well as 

provides current trends in global climate change. The recently released second volume of the 

Fourth National Climate Assessment focuses on the human welfare, societal, and environmental 

elements of climate change and variability for 10 regions of the United States (USGCRP 2018). 

The global climate is changing rapidly compared to the pace of natural climate variations that have 

occurred throughout Earth’s history. Evidence for these changes consistently points to human 

activities, especially emission of GHGs, as the dominant cause. Global average temperature has 

increased by approximately 1.8°F from 1901 to 2016. Without significant emission reductions, 

annual average global temperatures could increase by 9°F or more by the end of this century 

(compared to preindustrial temperatures) (Hayhoe et al. 2018).

Climate model projections for the Northern Great Plains (consisting of Montana, Wyoming, 

North Dakota, South Dakota, and Nebraska) indicate consistently warmer conditions in 2 to 3

decades and temperatures rising steadily into the middle of the century (Conant et al. 2018). This 

warming is predicted to occur along with less snowpack and a mix of increases and reductions in 

average annual water availability. Precipitation and streamflow show only modest changes, but 

many areas of the Northern Great Plains are already subject to high variability from year to year 

(both wet and dry years occur). The result of this high variability is low-probability, high-severity 

events such as extreme floods and droughts (Conant et al. 2018). Overall, climate models predict 

an increase in the number of heavy precipitation events (events with greater than 1 inch per day)

for much of the region, more very hot days (days with maximum temperatures above 90°F), and 

many fewer cool days (days with minimum temperatures less than 28°F; decreases of 30 days or 

more per year are predicted by approximately 2050). The increases in very hot days would have 

potential impacts on agriculture, energy production, human health, stream flows, snowmelt, and 

fires. The reduction in cool days would have implications for the region’s snowpack and, 

consequently, stream flow and water use (Conant et al. 2018). 

The EPA regulates GHG emissions under several initiatives, including the Mandatory Greenhouse 

Gas Reporting rule, the Final Greenhouse Gas Tailoring rule, geologic sequestration 

requirements, and EPA and National Highway Traffic Safety Administration standards for new 

motor vehicles. Under the Mandatory Greenhouse Gas Reporting rule (40 CFR 98), coal mines 

subject to the rule are required to report emissions in accordance with the requirements of 

Subpart FF. Subpart FF is applicable only to underground coal mines and would not apply to the 

Proposed Action. Because no change to the production levels or annual emissions at the Spring 

Creek Mine would occur under the Proposed Action, no other GHG reporting or permitting 

requirements would apply. 

3.4.1.5 Greenhouse Gases (GHGs)

According to the EPA and the Montana Climate Change Action Plan (CCAP), GHGs include CO2, 

methane (CH4), nitrous oxide (N2O) and several fluorinated species of gas (EPA 2018b) and 

CCAC 2007, respectively). CO2 is emitted from the combustion of fossil fuels, including coal. 

CH4 can be emitted during the production and transport of coal and N2O is emitted during 
Chapter 3 – Affected Environment

3-12 Spring Creek Mine TR1 EA

agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste. 

CO2 and other GHGs are naturally occurring gases in the atmosphere; their status as a pollutant 

is not related to their toxicity but instead is due to the added long-term impacts they have on 

climate because of their increased incremental levels in the earth’s atmosphere.

CO2 is the primary GHG emitted through human activities that contributes to climate change 

(81 percent of total U.S. GHG emissions in 2016); it is followed by methane (10 percent of total 

2016 emissions), N2O (6 percent of total 2016 emissions), and fluorinated gases (3 percent of 

total 2016 emissions) (EPA 2018b). The main human activity emitting CO2 is the combustion of 

fossil fuels (including the combustion of coal) for electricity, heat, and transportation (EPA 2018c). 

Methane, which is created during coal formation, is released from coal after it has been uncovered 

during surface mining operations. In addition, minor amounts of methane are released during coal 

extraction, storing, loading, and transport. Methane is also released during postmining operations 

as the coal is processed, transported, and stored for use. In addition, methane is emitted from 

the production and transport of natural gas and oil, as well as from livestock, other agricultural 

practices, and the decay of organic waste in municipal solid waste landfills (EPA 2018b). N2O is 

emitted from agricultural and industrial activities, as well as during the combustion of fossil fuels 

and solid waste. Fluorinated gases, which are synthetic, are emitted from a variety of industrial 

processes (EPA 2018b). 

The global warming potential (GWP) of gases was developed to allow comparisons of global 

warming impacts between different gases. The GWP of a gas depends on how well the gas absorbs 

energy and how long the gas stays in the atmosphere. It is a measure of the total energy that a 

gas absorbs over a particular period of time (usually 100 years) compared with CO2. CO2 has a 

GWP of 1. The larger the GWP, the more warming the gas causes. For example, methane’s 100-

year GWP is estimated to be 28 to 36, meaning that methane will cause 28 to 36 times as much 

warming as an equivalent mass of CO2 over a 100-year time period (EPA 2017b). The GWP for 

N2O is estimated to be 265 to 298.

The term carbon dioxide equivalent (CO2e) is used to describe different GHGs in a common 

unit. For any quantity and type of GHG, CO2e represents the amount of CO2 that would have 

the equivalent global warming impact (Brander 2012). Surface coal mines in the United States 

reported emissions of 7.2 million metric tons (MT) of methane CO2e in 2017 (out of a total of 

55.7 million MT of CO2e emissions from all U.S. coal mining and 6,456.7 million MT of CO2e 

emissions from all sources across the country) (EPA 2019a). These surface coal mine emissions 

represent 13 percent of all coal mining CO2e emissions and 0.1 percent of all CO2e emissions in 

the United States for 2017. 

The EPA’s Mandatory Greenhouse Gas Reporting rule requires industrial facilities and suppliers 

of fossil fuels or industrial gases that result in greater than 25,000 MT of CO2e of GHG emissions 

per year to report their emissions. Table 3-13 lists the industry sector, number of reporting 

facilities, and total GHG emissions for the United States and Montana for reporting year 2018 

from EPA’s Facility Level Information on Greenhouse Gases Tool (FLIGHT) (EPA 2019e). These 

data are useful to understand which large sources of anthropogenic emissions are contributing 

to GHG emissions both nationally and at the state level. 
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-13

Table 3-13. 2018 Greenhouse Gas Emissions from Large Facilities, by Sector

Industry Sector

Number of 

Reporting 

Facilities (U.S.)

Number of 

Reporting 

Facilities 

(Montana)

U.S. 

Reported 

GHG 

Emissions 

(million 

metric tons

CO2e)

Montana

Reported 

GHG 

Emissions 

(million 

metric tons

CO2e)

Global 

Anthropogenic 

GHG 

Emissions

Power plants 1,389 8 1,815 15.4 –

Petroleum and natural 

gas systems

2,319 6 316 0.1 –

Refineries 140 4 181 2.0 –

Chemicals 457 4 191 0.8 –

Other 1,316 3 130 0.2 –

Minerals 383 4 116 1.0 –

Waste 1,498 5 109 0.3 –

Metals 304 1 94 0.04 –

Pulp and paper 218 0 36 0 –

Total* 7,655 35 2,987 19.8 49,000†

* Total reporters shown may be less than the sum of the number of reporters in the selected source categories because some facilities fall 

within more than one source category.

†

Intergovernmental Panel on Climate Change (IPCC) (2014).

Further insight into trends in GHG emissions from large facilities in Montana can be seen in 

figure 3-2. FLIGHT Data from 2010 through 2018 show variation in annual GHG emissions per 

year, with an overall -21 percent decline in CO2e emissions in Montana from 2010 through 2018 

(EPA 2019d).

Figure 3-2. Montana annual CO2e, in million metric tons

The estimated CO2e emissions from coal mined at the SCM, based on average annual production 

between 2014 and 2018, are included in table 3-14. The inventories included emissions from all 

sources, including all types of carbon fuels used in the mining operations; electricity used on site 

(i.e., lighting for facilities, roads, and operations and electrically powered equipment and 

25.2

21.9

21.2

21.9

22.6

21.1 21.1

20.1 19.8

15.0

16.0

17.0

18.0

19.0

20.0

21.0

22.0

23.0

24.0

25.0

26.0

2010 2011 2012 2013 2014 2015 2016 2017 2018

CO2e (Million Metric Tons)

Year
Chapter 3 – Affected Environment

3-14 Spring Creek Mine TR1 EA

conveyors); and mining processes (i.e., blasting, coal fires caused by spontaneous combustion, and 

methane released [vented] from exposed coal seams). CO2e emissions generated by transporting 

the coal via rail to final destinations at power plants and loading terminals and from overseas 

vessel transport are also estimated, which were calculated using a per-trip weighted average of 

1,210 rail miles from the SCM to final destinations and 4,300 nautical miles for overseas transport. 

Discussions of shipping destinations are included in section 1.2.1.

The amount of CO2e emitted during the combustion of fossil fuels varies according to the carbon 

content and heating value of the fuel used (EPA 2008). As indicated in table 3-14, an average of

30.1 million metric tons of CO2e were produced annually between 2014 and 2018 (see appendix 

B for calculations).

Table 3-14. Estimated Equivalent CO2 (CO2e) Emissions from Coal Mined at the 

SCM

Source 2014-2018 Average Annual Emissions

Tons of Coal Recovered 14.21

Fuel 27,910

Electricity Consumed in Mining Process 45,322

Mining Process18,208

Total Direct Emissions 81,440

Haulage2931,448

From Coal Combustion 29,040,144

Total Indirect Emissions 29,971,592

Total Estimated CO2e Production 30,053,032

1. Blasting and methane emission

2. Includes rail and vessel transport

Source: WWC (2019), calculations are provided in appendix B

3.5 Water Resources

Section 3.5 of the 2010 LBM EA included detailed discussions of water resources related to 

MTM-069782. The analysis included herein serves to update discussions with recent groundwater 

and surface-water quality monitoring findings and update groundwater and surface-water rights 

discussions.

3.5.1 Groundwater

There are four major shallow geologic units related to the MTM-069782 containing groundwater 

that could be impacted by coal mining. These shallow units are the Quaternary alluvium, clinker 

(scoria or burn), overburden, and the Anderson/Dietz coal seam. Current groundwater 

monitoring well locations are indicated on map 3-3. Monitoring wells are identified by well 

number and completion aquifer, such as alluvium (6 wells), overburden/clinker (13 wells), 

interburden/underburden (2 wells), coal (23 wells), and backfill/spoil (8 wells).

According to groundwater quality monitoring results included in the SCM 2018 Annual Hydrology 

Report submitted to MDEQ, groundwater quality analyzed during the October 1, 2017 through 

September 30, 2018 reporting period was similar to the previous reporting period (SCC 2018b).

The results of 2018 groundwater quality monitoring are included in appendix C.
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-15

Map 3-3. Active Groundwater Monitoring Locations at the Spring Creek Mine
Chapter 3 – Affected Environment

3-16 Spring Creek Mine TR1 EA

Water quality is highly variable depending on the source aquifer. The dominant ionic constituents 

within the coal waters are sodium and bicarbonate. The average total dissolved solids (TDS) 

concentration in the Anderson/Dietz coal aquifer (from 18 wells monitored in 2018) was 

recorded at approximately 1,829 milligrams per liter (mg/L). As the groundwater moves 

downward through the overburden and into the coalbed aquifers, the water becomes less 

mineralized, which is due mainly to cation exchange (softening and sulfate reduction) mechanisms. 

The quality of groundwater from the Anderson/Dietz coal seam is generally suitable for domestic 

and livestock purposes; however, due to the high sodium adsorption ratio (SAR) (average 9.1), 

only crops with high salt tolerance can be irrigated with water directly from the Anderson/Dietz 

coal seam (Ayers and Westcot 1976). Based on pre-mining potentiometric maps (Van Voast and 

Hedges 1975), the flow direction of the pre-mine groundwater system was from recharge zones 

in highlands east and west of the mine toward the hydrologic discharge boundary formed by the 

Tongue River. Current groundwater conditions have changed in the SCM area as a result of 

coalbed natural gas (CBNG) development and ongoing mining operations at the SCM and Decker 

Mine. Because CBNG production requires the reduction of pressure head, pumping produced 

substantial, widespread water level decline in numerous coal aquifers in the Decker area 

(MDEQ-WQD 2020). Interpretative drawdown for the hydraulic properties of coal and 

overburden aquifers, such as conductivity and the capacity to store water, are changed in the 

process of removing overburden strata and returning it as spoil to mined-out pits. The spoil 

backfill has a more uniform hydraulic conductivity in contrast to undisturbed, bedded lithology 

where vertical conductivity is usually lower than horizontal conductivity (MDEQ-WQD 2020).

Dewatering and removal of aquifers during mining has caused temporary modifications of flow 

direction in the vicinity of the mine pits as groundwater moves toward depressed water levels in 

the pit area (MDEQ-WQD 2020). 

3.5.2 Surface Water 

The main surface water features within and adjacent to the SCM include the Tongue River 

Reservoir, North Fork Spring Creek, South Fork Spring Creek, Spring Creek, Pearson Creek, 

and Squirrel Creek. The ephemeral stream channels within the SCM area convey runoff and 

transport sediment loads, based on the magnitude of the runoff event. The TR1 Tract is located 

within the Pearson Creek and Spring Creek watersheds. The flows of Spring Creek and its north 

and south forks are currently detained in flood control reservoirs located upstream from the 

mining operation to keep the runoff out of the SCM pits. Pearson Creek flow is not currently 

detained by the mine, but flows have been substantially altered by a man-made diversion and 

impoundment associated with the West Pit of the Decker Mine. These flood control structures 

have been in place for several years, effectively cutting off Spring Creek and Pearson Creek flows 

upstream of the Tongue River. Stream flow and surface-water quality associated with the SCM 

are currently monitored at nine monitoring sites (map 3-4). Since the publication of the 2010 

LBM EA, three monitoring sites have been removed and two sites have been added to the MDEQapproved surface-water monitoring network for the SCM. Five sites (CB-2, SF-1R, RS-8, PC-1

ST

, 

and PC-2) provided data in 2018 (appendix C).
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-17

Map 3-4. Surface Drainages and Surface Water Monitoring Sites at the Spring 

Creek Mine
Chapter 3 – Affected Environment

3-18 Spring Creek Mine TR1 EA

The surface-water quality varies with stream flow rate; the higher the flow rate, the lower the 

TDS concentration but the higher the suspended solids concentration. Due to the flow 

fluctuations in South Fork of Spring Creek and Pearson Creek, the surface water quality is usually 

unsuitable for domestic use but suitable for irrigation and livestock use (Ayers and Westcot 

1976). In 2018, levels of dissolved aluminum, total iron, and total copper levels at several 

surface-water monitoring site were reported at levels above the DEQ-7 comparison criteria. 

Although elevated above the DEQ-7 comparison criteria, theses monitoring results represent 

ambient surface water conditions because some of the elevated levels were recorded at sites 

upstream of the mine, as well as sites within and below the mine. In 2018, levels of dissolved 

aluminum and conductivity levels at several surface-water monitoring sites were reported at 

levels above the MDEQ comparison criteria (SCC 2018b).

3.5.3 Water Rights

The Montana Department of Natural Resources and Conservation (DNRC) oversees surface 

water and groundwater rights in Montana. Prior to energy development in the area, water 

appropriations (either groundwater or surface water) were typically for livestock use. Currently, 

mining companies hold the majority of the water rights in the vicinity of the TR1 Tract. Records 

of the DNRC were searched for surface water and groundwater rights within a 2-mile radius of 

the tract to update water-rights information (Montana DNRC 2019).

DNRC records indicate that as of September 2019, there were 21 distinct (no duplicates) surface 

water rights within the 2-mile search area, of which 11 were owned by coal mining companies. 

The permitted surface-water rights uses include:

1. 9 stock

2. 3 industrial

3. 3 pollution abatement

4. 3 commercial

5. 2 sediment control

6. 1 irrigation

DNRC records indicate that, as of September 2019, there were 26 distinct groundwater rights

within 2 miles of the tract, of which, 18 are owned by coal mining companies. The permitted 

groundwater rights uses include:

1. 12 industrial

2. 8 stock

3. 3 pollution abatement

4. 2 domestic

5. 1 fisheries

3.6 Alluvial Valley Floors

Alluvial valley floors (AVFs) within the TR1 Tract are described in section 3.6 of the 2010 LBM 

EA. Two possible AVFs, Spring Creek and South Fork Spring Creek, were investigated in 1980 

to determine their AVF status (Volume 1, Section 17.24.325, SCC 2001). Spring Creek was found 

not to be an AVF. Approximately 90 acres of AVF delineated on South Fork Spring Creek were 

found to be an AVF that is insignificant to agriculture. Much of the South Fork Spring Creek AVF 

has already been disturbed, as approved in the current permit document. 
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-19

3.7 Wetlands/Aquatic Features

Wetlands/aquatic features within the TR1 Tract are described in section 3.7 of the 2010 LBM EA.

As verified by the U.S. Army Corps of Engineers (USACE), no potential jurisdictional wetlands 

were identified during field surveys of the TR1 Tract. Stock ponds and water impoundments with 

wetland soils, plants, and hydrology are present, but they are not considered jurisdictional 

because they either lack a continuous ordinary high-water mark or do not have a continuous 

nexus to other waters of the U.S. (WOTUS).

3.8 Soils

Soils within the TR1 Tract are described in section 3.8 of the 2010 LBM EA. The tract does not 

contain areas considered prime farmland. One map unit fits the criteria for prime farmland if 

irrigated but cultivation has not been historically practiced in this area and no reasonable sources 

of irrigation water are currently available. 

3.9 Vegetation

Vegetation within the TR1 Tract is described in section 3.9 of the 2010 LBM EA. The plant 

communities present in the tracts are representative of the Montana Mixed Prairie Association.

Much of the TR1 Tract occurs within a segment of the Pearson Creek drainage, which is 

characterized by stands of Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis), 

bluebunch wheatgrass (Agropyron spicatum), western wheatgrass (Agropyron smithii), little bluestem 

(Andropogon scoparius), silver sagebrush (Artemisia cana), winterfat (Ceratoides lanata), and black 

greasewood (Sarcobatus vermiculatus). Annual brome grasses are common in some areas of the 

drainage, as are a limited number of open and closed canopy forested areas. 

Surveys for threatened and endangered (T&E) plant species have been performed for the SCM

area. No T&E plant species (including Ute Ladies’ Tresses [Spiranthes diluvialis]) were located 

within the vicinity of the TR1 Tract. In addition, the U.S. Fish and Wildlife Service (USFWS) has 

not designated any “critical” habitat for this species in the vicinity of the TR1 Tract at this time 

(USFWS 2019a).

Two vegetative species of concern, as indicated by Montana Natural Heritage Program (MNHP), 

were recorded during the 2006-2007 vegetation surveys for Pearson Creek. Barr’s milkvetch 

(Astragalus barrii) and the woolly twinpod (Physaria didymocarpa) have been identified as occurring 

in the area. Barr’s milkvetch is listed as sensitive under the BLM classification and has an S3 state 

rank (potentially at risk because of limited range, population and/or habitat). The 2006-2007 

vegetation surveys indicated that Barr’s milkvetch was broadly distributed, if not abundant, within 

the TR1 Tract. The wooly twinpod has an S2S3 state rank (at risk because of very limited and/or 

potentially declining population numbers, range and/or habitat). SCM has voluntarily conducted 

extensive conservation efforts to grow the wooly twinpod in nurseries and outplant it into 

reclamation. The Nuttall desert-parsley (Lomatium nuttallii), an S1 ranked species (at high risk 

because of extremely limited and/or rapidly declining population numbers, range and/or habitat) 

has been observed in southeastern Montana but it have not been observed in the Spring Creek 

area.

3.10 Wildlife

Wildlife associated with the TR1 Tract is described in section 3.10 of the 2010 LBM EA. No 

substantial changes to wildlife use areas for other mammals, upland game birds (excluding the 
Chapter 3 – Affected Environment

3-20 Spring Creek Mine TR1 EA

Greater sage-grouse [GRSG] [Centrocercus urophasianus]), other birds, reptiles and amphibians, 

and aquatic species populations have been noted from the discussion presented in the 2010 LBM

EA. There have been changes in discussions related to big game; raptors; threatened, endangered, 

and candidate (T&E) species; and other species of special interest (SOSI), including federal Birds 

of Conservation Concern and Montana Species of Greatest Conservation Need (SGCN). The 

status of GRSG has also changed since publication of the 2010 LBM EA. Therefore, these species 

discussions have been updated in this EA.

3.10.1 Big Game

Extensive discussions of big game species (primarily pronghorn [Antilocapra americana], mule deer 

[Odocoileus hemionus], and white-tailed deer [Odocoileus virginianus]) were included in the 2010

LBM EA and in subsequent annual wildlife monitoring reports. The discussion included in this EA 

is related to an evaluation of Montana Fish, Wildlife and Parks’ (MFWP) classification of the tract

relative to their Crucial Areas Planning System (CAPS) for winter range habitat (MFWP 2016). 

None of the 728.4 acres of new disturbance associated with the TR1 Tract is considered high 

value big game winter range habitat, although approximately 546.3 acres (75.0 percent) of the 

proposed disturbance are considered moderate value big game winter range. The remaining 

182.1 acres (25.0 percent) are not rated as winter range. No big game migration corridors have 

been identified within or near the wildlife study area boundary.

3.10.2 Raptors

The 2018 annual report identified the location and annual status of raptor nests for 2018 (Great 

Plains Wildlife Consulting, Inc. [Great Plains Consulting] 2019). The location and status are 

included on (map 3-5). One intact raptor nest (TV2 - turkey vulture [Cathartes aura]) is located 

within the proposed disturbance limit needed to recover coal within the TR1 Tract. This species 

is a migratory bird, which is protected under the MBTA (USFWS 2019b). This nest has not been 

used since at least 1994. 

Raptor SOSI that could potentially occur in the area include the burrowing owl (Athene 

cunicularia), ferruginous hawk (Buteo regalis), bald eagle (Haliaeetus leucocephalus), golden eagle

(Aquila chrysaetos), northern goshawk (Accipiter gentilis), Swainson’s hawk (Buteo swainsoni), prairie 

falcon (Falco mexicanus), and peregrine falcon (Falco peregrinus) (appendix D). All of these species 

have been observed in the Spring Creek wildlife study area but none nest within the TR1 Tract

(map 3-5).

SCC has developed a general management plan regarding raptor SOSI that are known to or could 

occur in the vicinity of the mine. The intent of this SOSI monitoring and management plan is to 

provide broad, long-term direction for:

• monitoring populations of SOSI within the SCC wildlife study area boundary, and

• eliminating, minimizing, or mitigating potential impacts to these species due to mine 

operations, and maintaining, enhancing, and/or reclaiming habitats upon which such 

species depend. 
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-21

Map 3-5. Wildlife Use Associated with the TR1 Tract within the Spring Creek 

Mine Area
Chapter 3 – Affected Environment

3-22 Spring Creek Mine TR1 EA

3.10.3 Greater Sage-Grouse (GRSG)

Based on the current classification system for GRSG (MFWP 2019), the SCM annual wildlife 

monitoring area (see map 3-5) includes three confirmed active lek sites, five confirmed inactive 

leks, one unconfirmed site, and one confirmed extirpated (mined through) lek (table 3-15). 

Long-term results from annual lek monitoring (1981-2018) suggest that GRSG populations in the 

SCM annual wildlife monitoring area are cyclic, with periodic peaks and declines (Great Plains 

Consulting 2019). The population at SCM was highest during the late 1980s and mid-2000s. 

However, peak male counts did not exceed nine males over the monitoring period. Despite 

occasionally elevated GRSG numbers, peak counts at the monitored leks were below the 

long-term average of 2.9 males per lek during 19 of the last 39 years (Great Plains Consulting 

2019). This pattern is common throughout their range (Crawford et al. 2004). These data suggest 

that the SCM area may only support larger groups of GRSG when regional populations are 

especially high. 

Table 3-15. Peak GRSG Counts at Leks Within the Spring Creek Mine Annual 

Monitoring Area During Spring, 2018

LEK MALES FEMALES TOTAL CURRENT 

MANAGEMENT STATUS 1

Windmill 0 0 0 Confirmed Inactive

Pasture/

Alternate Pasture 0/0 0 0/0 Confirmed Active/Confirmed Active

Playa 0 0 0 Confirmed Active

Corral 0 0 0 Confirmed Inactive

Fenceline Playa/

Alternate Fenceline Playa 0/0 0/0 0/0

Confirmed Inactive/

Unconfirmed lek

Fenceline Playa II 0 0 0 Confirmed Inactive

West Bench 0 0 0 Confirmed Inactive

Upper Divide -- -- --

Confirmed Extirpated by fall 

1984

1 As defined by Montana Fish, Wildlife and Parks (2017): Active = at least two males present in at least 1 year followed by fresh sign within 10 

years of that observation; Inactive = no males present for last 10 consecutive years; Confirmed extirpated = lek site physically disturbed; 

Unconfirmed-Possible lek = grouse activity documented but insufficient data to classify as active.

3.10.4 Threatened, Endangered, and Candidate Species, and Special Status 

Species

3.10.4.1 Threatened, Endangered, and Candidate Species

The USFWS maintains a list of T&E species, and designated critical habitats on their official 

website for each county in Montana (USFWS 2018). The USFWS also provides the Information 

for Planning and Consultation (IPaC) system to evaluate the potential of encountering USFWS 

trust resources, including T&E species, related to a specific project area. The agency updates 

those species lists annually, or more frequently if any listing changes occur.

Vertebrate T&E species were discussed in section 3.10.7 of the 2010 LBM EA, which included 

evaluations of bald eagles, interior least terns (Sterna antillarum athalassos), and black-footed 

ferrets (Mustela nigripes). The current USFWS list of T&E species that may occur in Big Horn 

County, Montana only includes the black-footed ferret (USFWS 2018). The bald eagle was 

removed from the federal list of T&E species on August 9, 2007 (USFWS 2011) and the interior 

least tern is not included on the current T&E list for Big Horn County (USFWS 2018). The 
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-23

USFWS has not designated any “critical” habitat for any of these two species in the vicinity of the 

SCM at this time (USFWS 2019a). While the official list of T&E species that may occur in the TR1 

Tract (USFWS 2019a) indicated that there are no listed species identified within project area, the 

one species included on the county list will be reevaluated.

The black-footed ferret is listed as endangered, experimental, non-essential for the SCM area. 

Targeted surveys for this species have not yet been required or conducted for mine-related 

activities due to the lack of disturbance in potential habitat (prairie dog colonies). Neither ferrets 

nor their sign (e.g., trenching, scat, tracks) have ever been documented in the vicinity of the SCM, 

or at other regional mines, despite long-term annual monitoring (diurnal and nocturnal) of other 

wildlife species, including prairie dogs, and periodic targeted ferret surveys conducted in similar 

habitats elsewhere in the vicinity (Great Plains Consulting 2017). Based on the USFWS’s (2013) 

recent update to the Black-Footed Ferret Recovery Plan, the SCM is not located near an active 

or potential reintroduction area for this species. Based on a recent (2015) map of ferret 

reintroduction populations in Montana, the nearest reintroduction site is within the Crow 

Reservation, approximately 45 miles northwest of the SCM (Great Plains Consulting 2017).

3.10.4.2 Species of Special Interest (SOSI)

For the purposes of this discussion, SOSI include BLM-designated sensitive species, Montana 

Natural Heritage Program (MTNHP) species of concern (SOC), MFWP’s State Wildlife Action 

Plan (SWAP) species, and species under the jurisdiction of the USFWS through the MBTA or the

Bald and Golden Eagle Protection Act (BGEPA). USFWS T&E species are not included in this 

category since they are included in the T&E discussion, above. There is a considerable amount of 

crossover between the species occurrence on the various lists included in SOSI. BLM sensitive 

species include those species listed or proposed for listing under the ESA together with species 

designated internally as BLM sensitive in accordance with BLM Manual 6840 (BLM 2008). MTNHP

has developed a list of SOC in Montana that are native Montana animals that are considered to 

be "at risk" due to declining population trends, threats to their habitats, and/or restricted 

distribution (MTNHP 2019). Montana’s SWAP identifies community types, Focal Areas, and 

species in Montana with significant issues that warrant conservation attention (MFWP 2015). The 

MBTA makes it illegal to take, possess, import, export, transport, sell, purchase, barter, or offer 

for sale, purchase, or barter, any migratory bird, or the parts, nests, or eggs of such a bird except 

under the terms of a valid federal permit. The BGEPA prohibits taking bald eagles, golden eagles, 

or their eggs, parts, or nests without a permit issued by USFWS. MFWP-designated SGCN 

include wildlife species with low and declining populations that are indicative of the diversity and 

health of Montana’s wildlife (MFWP 2019). 

The SCC wildlife study area boundary is within Bird Conservation Region (BCR) 17 (Badlands 

and Prairies) of the United States (USFWS 2008). The 2008 (most current available) list of birds 

of Conservation Concern for BCR 17 contains 28 species (appendix D). Several of the species 

in BCR17 have been documented at least once within the SCM wildlife study area boundary over 

time, though nearly half of those observations occurred with varying degrees of infrequency. The 

most abundant species recorded over time consisted of common raptors and passerine species 

known to nest in the survey area.

Twenty-four of the 38 Montana vertebrate SOSI that could potentially occur in the area have 

been documented within or immediately adjacent to the SCC wildlife study area boundary, from 

1994 through 2018 (Great Plains Consulting 2019). The list includes 7 mammals, 14 birds, and 6

reptiles/amphibians. The entire SOSI list is included in appendix D.
Chapter 3 – Affected Environment

3-24 Spring Creek Mine TR1 EA

3.11 Land Use and Recreation

Land use and recreation (under Ownership and Use of the Land) on the TR1 Tract is described 

in section 3.11.1 of the 2010 LBM EA. The surface ownership within the LBM tract includes 

77.1 acres of federal BLM-administered land and 421.0 acres of private land. Livestock grazing

and wildlife habitat are the primary land uses.

3.12 Cultural Resources

Information regarding background cultural resources within the current SMP C1979012 permit 

boundary was included in section 3.12 of the 2010 LBM EA. A summary of the cultural resources 

management process for cultural resource sites inside SMP C1979012 as of 2018 is included in 

appendix E. According to information provided in SCC’s 2018 Annual Mining Report, 

122 cultural resources sites have been identified within the SMP C1979012 permit boundary, of 

which, 13 have been designated as eligible for listing on the National Register of Historic Places 

(NRHP). Only one (24BH3392) of the 13 NRHP eligible sites within the permit boundary is within 

the disturbance area associated with the TR1 Tract.

Native American tribes were consulted during the preparation of the 2010 LBM EA and this EA. 

In response to the 2010 LBM EA consultation, the Northern Cheyenne Tribe Preservation Office 

requested additional information and participated in a discussion of the cultural resource issues 

related to the TR1 Tract and accompanied mine personnel on tour of several of the sites on 

January 22, June 19 and 29, and July 1, 2009 and on January 14, 15, and 19, 2010. On February 

11, 2016, OSMRE requested continued consultation with Native American tribes for the stages 

of the proposal development and implementation of the final federal action. No Native American 

tribes responded to OSMRE’s consultation request.

3.13 Visual Resources

Visual resources related to the TR1 Tract is described in section 3.13.1 of the 2010 LBM EA. The 

SCM facilities and some mining activities are currently visible from Federal-Aid Secondary

(FAS) 314. Under the mine plan for the existing leases, mining has approached this public road 

and is plainly visible to passers-by. The TR1 located over 2.5 miles from FAS 314. The tract would 

not be plainly visible from the transportation corridor. Most of the people traveling this road are 

commuting to work at the SCM and the nearby Decker Mine. However, during periods of peak 

recreational activity this highway generates higher traffic volume. Landscapes found within and 

adjacent to the SCM area, and visible from FAS 314, include gently rolling benches of sagebrush, 

and mid-short-grass prairie. Major man-made intrusions include ranching, farming, transportation 

facilities and electrical power lines.

3.14 Noise

Noise related to the TR1 Tract is described in section 3.14.1 of the 2010 LBM EA. Existing noise 

sources in the area of proposed TR1 Tract are coal mining activities, agricultural and recreational 

activities, traffic on FAS 314 and the county road, rail traffic, boat traffic, and birds and animal life. 

FAS 314, which is a continuation of Wyoming Secondary Route 87, is over 2.5 miles from tract. 

This public highway is the primary route to and from work for the Sheridan residents employed 

at the mines north of Sheridan and is a secondary route for farm-market vehicles including large 

trucks. Traffic on FAS 314 is heaviest during the daylight hours and at shift changes. SCC has 

developed internal criteria on noise performance to ensure the protection of local community 

health and the environment. 
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-25

Noise and vibration are traditionally linked in environmental impact assessments for rail because 

the two disciplines are perceived to have many physical characteristics in common. Railroad 

operation noise can result from diesel locomotive engine and wheel/rail noise and horn noise, 

which includes locomotive warning horns sounding at at-grade rail/roadway crossings (Surface 

Transportation Board [STB] 2015a). Noise from trains is primarily a function of train speed, train 

length, track construction, and number and type of locomotives. Vibration caused by trains 

radiates energy into the adjacent soil in the form of different types of waves that propagate 

through the various soil and rock strata to nearby structures and other receptors.

A number of federal noise and vibration statutes, regulations, and guidelines are applicable to rail 

transport, including the Noise Control Act of 1972 (42 U.S.C.§ 4910), STB and Federal Railroad 

Administration (FRA) regulations and guidance, EPA’s Railroad Noise Emission Standards 

(40 C.F.R. Part 201), Federal Transit Authority (FTA) assessment methods, and noise limits 

related to occupational safety. 

3.15 Transportation

3.15.1 Vehicle Transportation

Transportation discussions related to the TR1 Tract are included in section 3.15.1 of the 

2010 LBM EA. Nearby transportation facilities include FAS 314 (which is a continuation of 

Wyoming Secondary Route 87) and local access roads. FAS 314 is classified as a two-lane, 

secondary major collector (MDT 2019). The highest annual average daily traffic (AADT) in the 

past 5 years on FAS 314 at a count station just north of the Montana/Wyoming border was 

866 vehicles (MDT 2019), which equates to 36 vehicles per hour. According to MDT information 

the design hourly volume for the road at this site in 2018 was 126. The highest AADT in the past 

5 years on FAS 314 at a count station approximately 3.5 miles south of the entrance to the of 

the SCM was 630 vehicles, which equates to 26 vehicles per hour. According to MDT information 

the design hourly volume for the road at this site in 2018 was 74 (MDT 2019).

3.15.2 Rail Transportation

Information is available on the destination of approximately 13.77 Mt of coal mined at the SCM 

is shipped to various destinations using a railroad spur owned by Spring Creek Coal and used by 

Burlington Northern-Santa Fe (BNSF) and BNSF-owned/maintained mainline railroad tracks

(map 1-3). According to U.S. Energy Information Administration (USEIA) information, 7.9 Mt of 

coal were shipped from the SCM in 2018 to six power plants in the U.S. (USEIA 2019). In addition,

the SCM shipped 4.5 Mt of coal to the Westshore Port in Washington for export overseas

(Table 3-16). The remaining 1.3 Mt of the 2018 SCM coal shipments were to various other 

destinations not accounted for in the USEIA database and the destinations were not publicly 

available. The USEIA information represents approximately 90 percent of the coal shipped from 

the SCM. Based on USEIA information, coal shipments utilized approximately 1,982,000 miles of 

rail lines for 797 round trips. Using a simple calculation of tons per train (15,600) and miles per 

ton (0.2), the remaining 1.3 Mt of coal would result in approximately 86 additional train round

trips and the utilization of approximately 213,150 miles of rail lines. The total rail miles for 2018

would be approximately 2,195,200 miles. For comparison purposes, in 2018 freight was hauled 

by rail in the U.S. over 476,500,000 miles (U.S. Department of Transportation [USDOT] 2019). 

Therefore, the annual rail transport of coal resulting from the 2018 SCM coal shipments 

represented approximately 0.46 percent of the total 2018 U.S. rail freight traffic.
Chapter 3 – Affected Environment

3-26 Spring Creek Mine TR1 EA

Table 3-16. Destinations, Tonnages, and Distances for Coal Mined at the SCM in 

2018

Destination Tons 

Shipped

Percent of 

Shipments

Number 

of Trips2

Round-trip 

Rail Miles1

Total Rail 

Miles

Asia

(Westshore Port, British Columbia)

4,503,000 36.22 289 3,000 865,962

DTE-BRSC Shared Storage

(Wisconsin) 3,756,426 30.22 241 2,064 497,004

Transalta Centralia Generation

(Washington) 2,361,244 18.99 151 2,400 363,268

Clay Boswell

(Minnesota) 659,895 5.31 42 1,954 82,656

Coronado

(Arizona) 563,243 4.53 36 2,876 103,839

Hoot Lake

(Minnesota) 326,360 2.63 21 1,660 34,728

Presque Isle

(Wisconsin) 260,860 2.10 17 2,064 34,514

Total (from USEIA) 12,431,028 90.3 797 16,018 1,981,971

Addition Shipments

(Information not publicly available) 1,337,027 9.7 86 3

-- 213,200 3

Total 13,768,055 100.00 883 316,018 2,195,171 3

1. Approximate miles

2. Round trip, based on an estimated 15,600 tons of coal per train

3. Estimated value

-- Data are not publicly available

Source: USEIA 2019

3.15.3 Vessel Transportation

At the Westshore Port, coal is loaded onto ocean-going vessels for overseas transport to ports 

in the Republic of Korea (ROK). The average ocean transport distance between Westshore and 

possible coal ports in the ROK is estimated to be approximately 4,300 nautical miles one-way 

(SCM 2019). Specific customers, combustion locations/facilities, and ports used are not known 

and would be too speculative to analyze further. Approximately 4.5 Mt of coal were shipped 

overseas in 2018, resulting in an estimated 36 round trip vessel (barge) trips.

3.16 Hazardous and Solid Wastes

Hazardous and solid waste discussions related to the TR1 Tract are included in section 3.16.1 of 

the 2010 LBM EA. Potential sources of hazardous or solid waste on the tract include spilling, 

leaking, or dumping of hazardous substances, petroleum products, and/or solid waste associated 

with coal mining activities. No such hazardous or solid wastes are known to be present on the 

tract at this time. Wastes produced by the mining and/or disturbance of the tract would be similar 

to those currently produced at the SCM.

3.17 Socioeconomics

Information regarding socioeconomics was included in section 3.17 of the 2010 LBM EA. 

Discussions related to housing, local government services, and environmental justice have not 

significantly changed enough to require reevaluation in the EA. Updated discussions on the local 

economy, population, and employment are included below.
Chapter 3 – Affected Environment

Spring Creek Mine TR1 EA 3-27

3.17.1 State/Local Economy

Montana has relied on its natural resources as a primary source of tax revenue. Generally, natural 

resource taxes are categorized as either severance/license taxes or some form of ad valorem 

(property) taxes. Total natural resource tax collection for the State of Montana in fiscal year (FY) 

2018 was $253,021,454. Montana coal severance taxes accounted for approximately 23 percent 

of the total 2018 FY tax revenues from natural resources (Montana Department of Revenue 

2018).

Coal production, as reported by the Montana Coal Council (2018), showed Montana’s coal 

production was 35.3 Mt in 2017. This was an increase of approximately 9.0 percent over the 

32.4 Mt produced in 2016. The 2017 production was less than the record 44.9 Mt produced in 

2008. Montana's output of coal has remained relatively constant since 1988, with relatively 

significant annual fluctuations. Montana was the seventh-largest coal producer among the 

50 states in 2016 (Montana Coal Council 2018).

Total cumulative royalties from the SCM amounted to approximately $482.4 million in 2017. SCC 

is the third largest surface coal mining monetary payer in the State of Montana (Montana Coal 

Council 2018). State and federal governments are the major beneficiaries of these payments, 

whereas private owners of pre-mining land leases are minor beneficiaries of these payments. 

Mineral royalties are collected on the amount of production and the value of that production. 

The current royalty rate for federal coal leases at surface mines is 12.5 percent, with half of this 

revenue returned to the state. Coal severance taxes are collected by the state of Montana. 

Currently, Montana collects 15 percent of the price of the coal as severance tax.

3.17.2 Population

According to U.S. census data, in 2018 Sheridan County had a population of 30,233 (U.S. Census 

Bureau 2019). The 2010 population of Sheridan County was 29,119. Therefore, there was an 

increase of 1,034 persons or 3.8 percent since SCM’s 2010 LBM EA was issued.

Population in Big Horn County, Montana continues to be sparse. According to the U.S. Census 

Bureau, Big Horn County had a population of 13,338 in 2018. The 2010 population of Big Horn 

County was 12,865. Between 2010 and 2018, the population of Big Horn County grew by 

approximately 3.7 percent (U.S. Census Bureau 2019).

3.17.3 Employment

A majority of the employees at the SCM reside in Sheridan County. The average total labor force 

in Sheridan County in December 2018 stood at 15,232 with an unemployment rate of 3.8 percent 

(Wyoming Department of Employment 2019). Total employment in Sheridan County generally 

decreased between December 2018, when compared to December 2017. In 2017, the largest 

employment sector in Sheridan County was the management, business, science, and arts sector, 

with 41.1 percent of the employees. This was followed by sales (20.2 percent), service (17.5

percent), natural resources, construction, and maintenance (12.1 percent), and production, 

transportation, and materials moving (9.2 percent) (U.S. Census Bureau 2019).

Decker and Spring Creek Mines are two of the three primary mining employers in Big Horn 

County. Montana receives the payroll taxes, royalties, and production taxes, but most of the 

employees reside in Sheridan County. In 2017, the Decker and Spring Creek mines employed 

137 and 247 people, respectively, with estimated payrolls of $11,037,000 and $23,677,000, 

respectively (Montana Coal Council 2018).

Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-1

4.0 Environmental Consequences/Cumulative Effects

4.1 Introduction

This chapter discusses the potential direct, indirect, and cumulative effects of the Proposed Action 

and the No Action Alternative, as described in chapter 2. The discussion is organized by the 

affected resource in the same order as they are described in chapter 3 and then by alternative. 

An impact, or effect, is defined as a modification to the environment brought about by an outside 

action. Impacts vary in significance from no change, or only slightly discernible change, to a full 

modification or elimination of the resource. Impacts can be beneficial (positive) or adverse 

(negative). Impacts are described by their level of significance (i.e., major, moderate, minor, 

negligible, or no impact). For purposes of discussion and to enable use of a common scale for all 

resources, resource specialists considered the following impact levels in qualitative terms.

• Major: Impacts that potentially could cause significant depletion, change, or stress to 

resources or stress within the social, cultural, and economic realm.

• Moderate: Impacts that potentially could cause some change or stress to an 

environmental resource but the impact levels are not considered significant.

• Minor: Impacts that potentially could be detectable but slight.

• Negligible: Impacts in the lower limit of detection that potentially could cause an 

insignificant change or stress to an environmental resource or use.

• No Effect/Impact: No discernible or measurable impacts.

Impacts can also be defined as direct, indirect, or cumulative. Terminology presented in this 

analysis includes the following:

• Direct impacts are defined as those impacts which are caused by the action and occur 

at the same time and place (40 C.F.R. § 1508.8(a)). 

• Indirect impacts are those that are caused by the action and occur later in time or are 

farther removed in distance but are still reasonably foreseeable (40 C.F.R. § 1508.8(b)). 

• Cumulative impacts are those impacts that result from incremental effects of an action 

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

regardless of what agency or other entity undertakes such other actions (40 C.F.R. § 

1508.7). Cumulative impacts occur over a given time period when the impacts of past, 

present, and reasonably foreseeable future actions overlap with the time period when 

project impacts would occur (including the coal recovery and reclamation phases).

The duration of impacts is also presented throughout this chapter, as follows:

• Short-term impacts generally occur over a relatively short period and revert to 

pre-disturbance conditions within a few years after mining occurs. For the purposes of 

the evaluation, short-term impacts include those related to the actual mining of the 

coal, which estimated to be completed in the TR1 Tract by 2031.

• Long-term impacts are defined as those that would remain beyond mining-related 

activities (including reclamation), generally, lasting the life the alternative being 

evaluated (e.g., federal mining plan modification approval) and beyond.

The direct, indirect, and cumulative effects of the Proposed Action and No Action Alternative are 

comparable to those described in the 2010 LBM EA, except as noted herein. In addition to 

addressing the specific issues identified in chapter 1, these updated environmental consequences 
Chapter 4 – Environmental Consequences/Cumulative Effects

4-2 Spring Creek Mine TR1 EA

analyses reflect changes to the mining operations presented in chapter 2 and any updated 

descriptions of the affected environment presented in chapter 3 that have taken place since the 

2010 LBM EA and the 2012 federal mining plan modification were approved. The environmental 

consequences have been assessed assuming a 14.2-Mtpy production rate. The estimated annual 

production is in line with recent annual production, as discussed in section 1.2.1.

Regarding other relevant regional activity, the Decker Mine is a surface coal mine owned and 

operated by Lighthouse Resources Inc., located approximately 1.5 miles southeast of the TR1 

Tract. The permitted mine operations area for the Decker Mine is approximately 11,718 surface 

acres and the 2017 coal production was 4.2 million tons. 

Lighthouse Resources, Inc. also owns the Big Horn Mine, which is a surface coal mine 

approximately 12 south of the TR1 Tract. The mine’s permitted mine operations area is 

approximately 1,385 acres. The mine is no longer producing coal and is awaiting final bond release 

on the completed reclamation.

The Absaloka Mine is a surface coal mine located on and adjacent to the Crow Reservation, owned 

and operated by Westmoreland Resources, Inc. The mine is located approximately 45 miles 

northwest of the SCM. The permitted mine operations area is approximately 10,427 surface acres

and the 2017 coal production was 3.6 million tons. 

Brook Mining Company LLC., a subsidiary of Ramaco, LLC, has submitted a mining-permit 

application to the WDEQ-LQD to mine a maximum of 8 Mtpy of coal using a highwall mining 

technique. The Brook Mine is located in Wyoming, approximately 15 miles southwest of the SCM 

and encompasses approximately 4,549 acres of privately-held coal resources. Recoverable coal 

resources held by Ramaco are approximately 100 Mt (Billings Gazette 2014). While the mine plan 

is still under review by WDEQ-LQD and the mine is not yet operational, it is likely that mining 

will be initiated before 2031. 

The Youngs Creek Mine is owned by NTEC and is located in Wyoming approximately 7 miles 

southwest of the SCM. It encompasses approximately 7,822 acres of predominately privately-held 

coal resources and surface rights. Estimated recoverable coal resources are 287 Mt (CPE 2015). 

The mine is permitted, but there are no current mining operations. Due to the uncertainty of 

development and the length of time required for project startup and development, this mine would 

not be fully operational by 2031. Therefore, this proposed project is not included in the cumulative 

effects analysis.

Big Metal Coal, a wholly-owned subsidiary of NTEC, and the Crow Tribe of Indians signed an 

exploration agreement and option to lease up to 1.4 billion tons of coal from three project areas 

in the southeast corner of the Crow Indian Reservation west of SCM. On June 7, 2018, Big Metal 

Coal provided the Crow Tribe notice it was exercising its lease option on the Upper Youngs 

Creek project area and extending its coal lease options for the Squirrel Creek and Tanner Creek 

project areas. After Big Metal Coal and the Crow Tribe sign the Upper Youngs Creek coal lease, 

the coal lease will require approval from the DOI and will require related regulatory actions before 

the lease is effective. The Big Metal Project is not under concurrent consideration by any state 

agency through pre-impact statement studies, separate impact statement evaluation, or permit 

processing procedures. Due to the uncertainty of development and the length of time required 

for project startup and development, this mine would not be fully operational by 2031. Therefore, 

this proposed project is not included in the cumulative effects analysis.
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-3

There are no conventional oil and gas facilities associated with the tract or within 2 miles of the 

tract and CBNG recovery has essentially ceased in Big Horn and Rosebud counties (Montana 

Board of Oil and Gas Conservation [MBOGC] 2019). The nearest coal-fired power plants are the 

Colstrip coal-fired power plant, located about 55 miles north-northeast of the tract, and the 

Hardin plant, located about 57 miles northwest of the tract (map 3-2).

The environmental and cumulative effects discussions below assume that under the Proposed 

Action, the federal mining plan modification to mine coal in the remaining federal coal lease 

MTM-069782 would be approved. Impacts from coal recovery related to the Proposed Action will 

be assessed using an annual production rate of 14.2 Mt, which is the 2014 through 2018 average 

annual production. Since the actual destinations of future coal shipments are not known at this 

time, impacts assessments related to coal shipments will utilize variables associated with 2014

through 2018 destinations. The recovery of the remaining federal coal would add approximately 

4 additional years to the LOM, to 2031. 

Under the No Action Alternative, the federal mining plan modification for the federal coal would 

not be approved. SCM would mine its remaining 75.7 Mt of recoverable federal coal reserves 

within the existing mine leases in approximately 5.3 years at an average production rate of 

14.2 Mtpy.

4.2 Topography and Physiography

4.2.1 Direct and Indirect Effects 

4.2.1.1 Proposed Action

The direct and indirect effects to topography and physiography would not be substantially different 

than those described in Section 4.1.1 of the 2010 LBM EA. The Proposed Action would impact 

the topography and physiography of the remaining portions of lands included in MTM-069782, but 

these impacts would be similar to those currently occurring on the existing SCM coal leases as 

coal is mined and the mined-out areas are reclaimed. The direct effects on topography and 

physiography resulting from the Proposed Action are expected to be moderate and permanent 

on the tract. There would be no indirect effects under the Proposed Action.

4.2.1.2 No Action Alternative

The impacts to topography under the No Action Alternative would be similar in nature to those 

under the Proposed Action but the magnitude of the impacts would be reduced since disturbance 

to 728.4 acres to recover federal coal within the tract would not occur.

4.2.2 Cumulative Effects

The cumulative effects to topography and physiography would not be substantially different than 

those described in the 2010 LBM EA and primarily be related to the existing SCM and the adjacent 

Decker Mine. Following surface coal mining and reclamation, topography would be modified and 

the topography outside of the valley bottoms would be less rugged, more homogeneous, and 

gentler. In general, pre-mining features that were more topographically unique (e.g., steeper hills 

and ravines, rock outcrops, etc.) would be smoothed with more uniform slopes. The cumulative 

effects on topography and physiography resulting from the Proposed Action are expected to be 

moderate and permanent on the tract.
Chapter 4 – Environmental Consequences/Cumulative Effects

4-4 Spring Creek Mine TR1 EA

4.2.3 Mitigation Measures

No mitigation measures would be necessary for topography.

4.3 Geology, Mineral Resources, and Paleontology

4.3.1 Direct and Indirect Effects

4.3.1.1 Proposed Action

The direct and indirect effects to geology, mineral resources, and paleontology would not be 

substantially different than those described in Section 4.1.2 of the 2010 LBM EA. The stratigraphic 

units from the base of the Anderson/Dietz coal seam to the land surface would be subject to 

permanent change (mixing) on the areas of coal removal and mining would alter the resulting 

subsurface physical characteristics of these lands. These impacts are occurring on the existing SCM 

coal leases as coal is mined and the mined-out areas are reclaimed. The Proposed Action would 

result in the recovery of approximately 53.6 Mt of federal coal within the Anderson/Dietz coal 

seam. The Proposed Action would also result in the loss of CBNG though venting and/or depletion 

of hydrostatic pressure in Anderson/Dietz coal resulting from mining adjacent areas. The Proposed 

Action would not impact conventional oil and gas recovery since there are no conventional oil 

and gas facilities within the tract and oil and gas producing formations are well below geological 

layers affected by mining.

As of September 11, 2019, 908 CBNG wells had been completed within the CX Field, which 

includes the TR1 Tract (MBOGC 2019), but no CBNG wells have been completed within the 

tract. The Final Montana Statewide Oil and Gas Environmental Impact Statement and Proposed 

Amendment of the Powder River and Billings Resource Management Plans (BLM 2003) assumed 

an average well life of 20 years for CBNG wells in the PRB of Montana, based on a review of 

average production well life for existing wells east and west of the Tongue River. It is unlikely that 

any CBNG would be recovered from the Anderson/Dietz coal seam within the TR1 Tract due to 

the absence of existing CBNG wells on the tract and the relatively fast onset of mining activity 

scheduled for the tract, if the federal mining plan modification request is approved. CBNG reserves 

not recovered from the Anderson/Dietz coal seam prior to mining would be vented to the 

atmosphere. There are no existing facilities or equipment associated with CBNG production and 

development on the tract.

No unique or significant paleontological resources have been identified or are suspected to exist 

on the tract. The likelihood of encountering significant paleontological resources is very small. 

Lease and permit conditions require that should previously unknown, potentially significant 

paleontological sites be discovered, work in that area must stop and measures must be taken to 

assess and protect the site.

The direct and indirect effects on mineral resources and paleontology are expected to be 

moderate and permanent on the tract.

4.3.1.2 No Action Alternative

The impacts to geology, mineral resources, and paleontology under the No Action Alternative 

would be similar in nature to those under the Proposed Action but the magnitude of the impacts 

would be reduced since disturbance to 728.4 acres to recover federal coal within the tract would 

not occur. Impacts to CBNG resources would be moderate and permanent as a result of mining 

activities on adjacent lands.
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-5

4.3.2 Cumulative Effects

The cumulative effects to geology, mineral resources, and paleontology would not be significantly 

different than those described in the 2010 LBM EA but would be extended by approximately 

4 years, to 2031. The cumulative effects would primarily be related to the existing SCM and the 

adjacent Decker Mine but, to a minor extent, would also include the PRB coalfield, which 

encompasses an area of about 12,000 square miles. The U.S. Geological Survey (USGS) estimate 

that there are approximately 162 billion tons of recoverable coal in the PRB, of which, an estimated 

25 billion tons are considered economically recoverable coal, with a maximum stripping ratio of 

10:1 (USGS 2013). The recovery of 53.6 Mt of coal related to the Proposed Action would have a 

minor impact on the availability of coal in the region.

There would not be cumulative impacts to conventional oil and gas recovery since there are no 

conventional oil and gas facilities within the tract and producing formations are well below the 

geological layers affected by mining.

According to September 11, 2019 information from the MBOGC website, 1,119 CBNG wells have 

been drilled in Big Horn County and 6 CBNG wells have been drilled in Rosebud County. The 

MBOGC records indicate that a majority of the wells are privately held or state minerals, with 

only approximately 16 percent of the wells (176 of 1,119) being federal minerals. Status of these 

wells includes shut-in, producing, plugged and abandoned, and injection. As of September 2019, 42

of the CBNG wells in Big Horn County were considered to be in production. No CBNG wells 

drilled in Rosebud County were in production. The pace of CBNG development in Montana has 

recently slowed considerably (MBOGC 2019). No production has been reported from the CX 

Field, which is adjacent to the TR1 Tract, since 2013 (MBOGC 2019).

Impacts to paleontological resources as a result of the currently authorized and reasonably 

foreseeable cumulative energy development occurring in the PRB consist of losses of plant, 

invertebrate, and vertebrate fossil material for scientific research, public education (interpretive 

programs), and other values. Losses would result from the destruction, disturbance, or removal 

of fossil materials as a result of surface-disturbing activities, as well as unauthorized collection and 

vandalism. A beneficial impact of surface mining can be the exposure of fossil materials for scientific 

examination and collection, which might never occur except as a result of overburden removal, 

exposure of rock strata, and mineral excavation. The cumulative effects on geology, mineral 

resources, and paleontology resulting from the Proposed Action are expected to be moderate on 

the local area and minor on a regional basis but the cumulative impacts would be permanent.

4.3.3 Mitigation Measures

No mitigation measures would be necessary for geology or mineral resources. Should significant 

paleontological resources be encountered as a result of the Proposed Action, the appropriate 

agencies would be consulted.

4.4 Air Quality

4.4.1 Particulate Matter

4.4.1.1 Direct and Indirect Effects 

4.4.1.1.1 Proposed Action

The direct and indirect effects to air quality from particulate matter would not be different than 

those described in section 4.1.3 of the 2010 LBM EA. Direct emissions from particulate matter 
Chapter 4 – Environmental Consequences/Cumulative Effects

4-6 Spring Creek Mine TR1 EA

from the Proposed Action would include fugitive emissions generated from coal excavation and 

reclamation activities and tailpipe emissions from equipment. Fugitive particulate emissions would 

also result from dust being generated during dragline operation, coal haulage, bulldozers, scrapers, 

loaders, baghouse, and other equipment operating at SCM. The results of 24-hour and annual 

dispersion modeling are included in table 4-1. Under the modified federal mining plan proposed, 

the SCM would not cause or contribute to a violation of the federal 24-hour PM10 NAAQS of 150 

μg/m3(CPE/Redhorse 2014).

Table 4-1. SCM Particulate Matter Dispersion Modeling Results

Pollutant Averaging

Period

Modeled 

Concentration 

(μg/m3)

Background 

Concentration 

(μg/m3)

Total 

Concentration 

(μg/m3)

NAAQS/MAAQS

(μg/m3)

2016 Mine Year

PM10 24 hour 76.55a33.0 109.55 150c

Annual 20.22b17.5 37.72 50d

PM2.5 24 hour 11.15b15.0 26.15 35e

Annual 4.13b

4.13

5.5 9.63 12f

2018 Mine Year

PM10 24 hour 90.82a33.0 123.82 150c

Annual 23.98b17.5 41.48 50d

PM2.5 24 hour 14.53b15.0 29.53 35e

Annual 4.14b

4.14

5.5 9.64 12f

a Highest, second-high modeled value

b Highest modeled value

c Violation occurs with more than one expected exceedance per calendar year, averaged over 3-years

d Violation occurs when the 3-year average of the arithmetic means over a calendar year exceeds the value. EPA revoked the annual PM10

standard effective December 17, 2006.

e Violation occurs when the 3-year average of the 98th percentile values exceed the standard. Per EPA policy, use the maximum modeled 

concentration for comparison to the standard.

f Violation occurs when the 3-year average of the spatially averaged calendar year means exceed the standard

PM10 and PM2.5 inventories for the mining activities at SCM were prepared for all years in the 

currently anticipated LOM. Two years were then selected for worst-case dispersion modeling of 

PM10 and PM2.5 based on mine plan parameters and emission inventories. Fugitive emission sources 

and point sources were modeled using AERMOD. The modeling follows the methods presented 

in a dispersion modeling protocol for the project submitted to MDEQ in April 2013 

(CPE/Redhorse 2014) and on MDEQ comments on the original modeling analysis submitted 

September 2013. Per MDEQ guidance, modeling for NO2 was not required because increased 

NOX potential to emit (PTE) would be well below 40 tpy (CPE/Redhorse 2014).

The dispersion modeling was conducted for a revision to air quality permit MAQP #1120-12 and 

was based on a production rate of 30.0 Mtpy, which is over 2 times greater than the anticipated 

production for the SCM evaluated in this EA (14.2 Mtpy). Modeling indicates the currently 

projected mine activities would be in compliance with the 24-hour and annual PM10 ambient air 

standard for the life of the SCM. Based on mine plan parameters and highest emissions inventories, 

the years 2016 and 2018 were selected as the worst-case years for evaluation, because those years 

had the highest modeled PM10 concentrations. The results of 24-hour and annual dispersion 

modeling are included in table 4-1. Under the Proposed Action, the SCM would not cause or 

contribute to a violation of the federal 24-hour PM10 NAAQS of 150 μg/m3(CPE/Redhorse 2014).
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-7

An inventory of all point sources, controls, and emissions for the MAQP #1120-12 air quality 

permit showed a maximum potential to emit 21.0 tpy; therefore, a PSD increment consumption

analysis was not necessary (a value below the 100 tpy major source threshold limit specified in 

ARM 17.8, Subchapter 8 – PSD and Subchapter 12 – Operating Permit Program means that SCM 

would not be subject to the Title V operating permit program (CPE/Redhorse 2014)).

There have been no recorded exceedances of the 24-hour or annual PM10 NAAQS or MAAQS at 

the SCM, and, based on estimated PM2.5 values, there were no exceedances of the 24-hour or 

annual PM2.5 NAAQS at the mine. The 2014 AERMOD modeling conducted for the current SCM 

permit predicted no future exceedances of the 24-hour and annual PM10 NAAQS/MAAQS at a 

30 Mtpy production rate. The 2014 AERMOD modeling also predicted no future exceedances of 

the 24-hour or annual PM2.5 NAAQS at a 30-Mtpy production rate (CPE/Redhorse 2014).

At the estimated average annual production rate of 14.2 Mt mining would be extended by

approximately 4 years to 2031 and there would be an increase in overburden thickness; however,

fugitive dust emissions are projected to remain within daily and annual NAAQS and MAAQS limits. 

The direct and indirect effects from particulate matter emissions resulting from the Proposed 

Action are expected to be moderate but extended to 2031 on the tract. As discussed in section 

4.4.3, the effects of particulate matter emissions from coal combustion would be minor, when 

compared to total U.S. particulate emissions.

4.4.1.1.2 No Action Alternative

Impacts from particulate matter emissions have resulted from current mining activity and therefore 

under this alternative, particulate matter emission impacts in the area would be similar to those 

under the Proposed Action but would not be extended for an additional 4 years.

4.4.1.2 Cumulative Effects

The cumulative effects from particulate matter emissions are expected to be moderate but 

extended to 2031. Cumulative impacts from particulate matter emissions could be higher in the 

short term in this area due to coal mining activities if surface inversion occurs in the region. An 

inversion can occur when a layer of cooler air is trapped near the ground by a layer of warmer air 

above, allowing particle pollution levels to increase before the inversion lifts (EPA 2019e). This 

would be temporary, lasting only during the inversion. Air quality impacts would cease to occur 

after mining and reclamation are complete. The effects of particulate matter emissions from coal

combustion are included in section 4.4.3. The Decker Mine, located adjacent to the SCM, would 

contribute additional particulate matter emissions to the surrounding area. Modeling conducted 

for MAQP #1120-12 air quality permit included effects from the Decker Mine. As the model 

indicated, under the modified federal mining plan proposed, the SCM would not cause or 

contribute to a violation of the federal 24-hour PM10 NAAQS of 150 μg/m3(CPE/Redhorse 2014).

4.4.1.3 Mitigation Measures

No mitigation measures beyond those required by the SCM air quality permit would be required 

for emissions of particulate matter (CPE/Redhorse 2014).
Chapter 4 – Environmental Consequences/Cumulative Effects

4-8 Spring Creek Mine TR1 EA

4.4.2 Emissions of Nitrogen Oxides (NOX) and Ozone (O3)

4.4.2.1 Direct and Indirect Effects 

4.4.2.1.1 Proposed Action

While, per MDEQ guidance, modeling for NO2 is not required because estimated NOX PTE would 

be well below 40 tpy, the SCM did model for total annual NOX emissions for 2013 through 2025. 

As with particulate matter modeling, the years 2016 and 2018 were selected as the worst-case 

years, because those years had the highest modeled NOX concentrations. NOX modeling closely 

followed many of the same procedures used in the PM10 analysis. Emissions were apportioned in 

a similar manner and the same meteorological data set was used. Area source, haul road, and point 

source information for the SCM and Decker Mine and information for railroads, roads, power 

plants, and regional sources provided by MDEQ ARMB were included in the model (CPE/Redhorse 

2014). The amount of NOX emissions from blasting is related to the amount of ammonium nitrate 

fuel oil (ANFO) blasting agent used. Total annual NOX emission rates for 2016 and 2018 were 

modeled to be 558.9 ton and 555.8 ton, respectively. These NOX values were included in SCC’s 

2014 air quality permit application that was submitted to MDEQ-ARMB, for a revision to MAQP 

#1120-12 (CPE/Redhorse 2014). MDEQ-PCD determined that, based on the modeling analysis 

and past monitoring, mining at a 30.0 Mtpy rate would not likely substantially degrade air quality 

(MDEQ-PCD 2014). Public exposure to NOX emissions caused by surface mining operations is 

most likely to occur along publicly accessible roads and highways that pass through the area of the 

mining operations. Occupants of residences in the area could also be affected. The closest public 

transportation route is Route FAS 314, which is within approximately 1.4 miles northeast of the 

proposed TR1 Tract disturbance and there are occupied dwellings located approximately 2.8 miles 

north of the disturbance. The nearest recreational opportunities are at the Tongue River 

Reservoir, approximately 2.6 miles east of the tract. The direct and indirect effects from NOX

emissions resulting from the Proposed Action are expected to be moderate but extended to 2031

on the tract.

Based on information included in the PAP that mining methods would not be significantly different 

than those currently employed at the mine (SCC 2019), the direct and indirect effects from O3

emissions resulting from the Proposed Action are expected to be minor but extended to 2031.

4.4.2.1.2 No Action Alternative

Impacts from NOX and O3 emissions have resulted from current mining activity and therefore the 

impacts related to NOX and O3 emissions under the No Action Alternative would be similar to 

those under the Proposed Action but would not be extended for an additional 4 years.

4.4.2.2 Cumulative Effects

The cumulative effects from NOX and O3 emissions are expected to be moderate but extended

to 2031. Cumulative impacts from NOX and O3 could be higher in the short term in this area due 

to coal mining activities if surface inversion occurs in the northern portion of the PRB. This would 

be temporary, lasting only during the inversion. Air quality impacts would cease to occur after 

mining and reclamation are complete.

4.4.2.3 Mitigation Measures

No mitigation measures beyond those required by the SCM air quality permit would be required 

for emissions of NOX or O3.
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-9

4.4.3 Emissions of Sulfur Dioxide (SO2), Mercury (Hg), Lead (Pb), and Other

Non-Greenhouse Gases (Non-GHG)

4.4.3.1 Direct and Indirect Effects 

4.4.3.1.1 Proposed Action

As presented in table 3-8, SO2 data collected at the three sites were below the 1-hour MAAQS 

(0.50 ppm) 99th percentile concentrations. Therefore, it is likely that ambient air quality within 

the vicinity of the Proposed Action is currently in compliance with the SO2 MAAQS and NAAQS.

Given the absence of CO nonattainment areas in the region and the results of ongoing SO2, Hg, 

and Pb monitoring in the area that show no exceedances of these AQ parameters, the effects of 

emissions of CO, SO2, Hg, and Pb from the Proposed Action would be minor but would be 

extended to 2031.

4.4.3.1.2 No Action Alternative

Impacts from non-GHG emissions have resulted from current mining activity and therefore the 

impacts related to non-GHG emissions under the No Action Alternative would be similar to those 

under the Proposed Action but would not be extended for an additional 4 years.

4.4.3.2 Cumulative Effects

The mines in Big Horn and Rosebud counties would contribute additional non-GHG emissions to 

the surrounding area. Based on past monitoring, the permit modification request would not likely 

increase SO2, Hg, or Pb emissions. While cumulative impacts from non-GHG emissions could be 

higher in the short term in this area due to coal mining activities if surface inversion occurs in the 

northern portion of the PRB, this would be temporary, lasting only during periods of inversions. 

Air quality impacts from mining would cease to occur after reclamation is complete. Therefore, 

the cumulative effects from SO2, Hg, and Pb emissions are expected to be minor but extended to 

2031.

4.4.3.3 Mitigation Measures

No mitigation measures beyond those required by the SCM air quality permit would be required 

for emissions of non-GHGs.

4.4.4 Air Quality Related Values (AQRVs)

4.4.4.1 Direct and Indirect Effects 

4.4.4.1.1 Proposed Action

Visibility

Techniques for blasting, coal removal, and coal processing would be expected to continue as 

described in the approved MAQP #1120-12 (MDEQ-PCD 2014). Material movement would 

continue to utilize direct cast blasting, draglines, and/or truck and shovel fleets for overburden and 

truck and shovel fleets and overland conveyors within the permit area to transport coal to 

processing facilities for coal. Thus, emissions from blasting are not expected to increase 

substantially. The expected levels of pollutants and particulates that effect visibility would be within 

the approved MAQP #1120-12. The proposed project area is not directly influenced by other air 

quality regulations (i.e., Class I air shed). The direct and indirect effects to visibility resulting from 

the Proposed Action are expected to be moderate but extended to 2031.
Chapter 4 – Environmental Consequences/Cumulative Effects

4-10 Spring Creek Mine TR1 EA

Air Quality Related Values Related to Coal Combustion

Emissions that affect air quality also result from combustion of fossil fuels. Table 4-2 presents the 

estimated PM10, PM2.5, SO2, NOX, and Hg emissions estimates from coal mined at the SCM used 

for power generation in comparison with 2014 through 2018 values. Estimated annual emissions

for 2020 through 2031 are also provided based on the projected average coal recovery for the 

time period and the weighted average of distances and tons of coal shipped.

Based on emissions shown in table 4-2, indirect impacts to air quality related to coal combustion 

under the Proposed Action would be within the 2014 through 2018 emission ranges estimated for

combustion of SCM coal. When compared to total U.S. emissions, indirect effects would be minor 

(less than one percent of the U.S. average emissions) but they would be extended by approximately 

4 years, to 2031.

Table 4-2. Estimated Annual PM10, PM2.5, SO2, NOX, Hg, and CO Contributions 

from Coal Combustion for 2014-2018 and 2020-2031, Compared to 

2014 U.S. Total Emissions

Source: WWC completed calculations, which are provided in appendix B.

Acidification of Lakes

The SCM is not required by MDEQ to monitor H2S so a direct comparison to MAAQS standards 

is not possible. Because factors affecting H2S emissions would not change as a result of the 

Proposed Action, the direct and indirect effects have been inferred from the currently permitted 

impacts of mining the existing coal leases at the SCM. As indicated in table 3-12, the 2014-2018

trend in H+ at monitoring site MT00 appears to be relatively stable. Based on this comparison of 

the current information available, the Proposed Action is not expected to contribute to increased 

direct or indirect effects from acidification of lakes

4.4.4.1.2 No Action Alternative

Impacts to air quality related values have resulted from current mining activity and therefore the 

impacts related to AQRVs under the No Action Alternative would be similar to those under the 

Proposed Action but would not be extended by 4 years.

Source 2014 2015 2016 2017 2018

2014-

2018 

Average

2020-

2031

Average

2014

Total 

U.S. 

2020-2031

Average % 

U.S.

Mt Tons of Coal 

Recovered 17.3 17.0 10.3 12.7 13.6 14.2 14.2 -- --

PM10 (Tons) 3,872.9 3,797.5 2,293.4 2,846.4 3,033.1 3,168.7 3,168.7 20,616,000 0.02%

PM2.5 (Tons) 1,181.2 1,158.2 699.5 868.1 925.1 966.4 966.4 6,033,000 0.02%

SO2 emissions 

(Tons) 71,421.0 70,030.0 42,293.5 52,490.2 55,934.1 58,433.8 58,433.8 4,991,000 1.17%

NOX emissions 

(Tons) 27,597.2 27,059.7 16,342.3 20,282.3 21,613.0 22,578.9 22,578.9 12,412,000 0.18%

Hg emissions

(Tons) 0.28 0.27 0.16 0.20 0.22 0.23 0.23 52.0 0.44%

CO emissions

(Tons) 4,298.8 4,418.9 4,331.2 4,246.9 2,564.8 3,183.2 3,392.0 52,483,810 0.01%
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-11

4.4.4.2 Cumulative Effects

Blasting, coal crushing, loading and hauling of coal, moving equipment, and other activities 

associated with surface coal mining, the combustion of coal at power plants, and activities related 

to CBNG produce particulates that can be released into the air that could impact AQRVs.

As discussed in section 3.4.1.3, the nearest Class I area is located approximately 19 miles north 

of the tract at the Northern Cheyenne Indian Reservation. Because this Class I area is not in line 

with the prevailing wind (see section 3.4), it would not be impacted by the Proposed Action and 

is not included in the cumulative effects analysis. Section 4.1 indicates that CBNG activity has 

essentially ceased in Big Horn and Rosebud counties.

The cumulative effects on AQRVs are expected to be moderate but extended to 2031. Cumulative 

impacts to AQRVs could be high in the short term in this area due to coal mining activities if 

surface inversion occurs in the northern portion of the PRB. This would be temporary, lasting only 

during the inversion. Inversion modeling was not conducted for the SCM area, but all air quality 

standards are currently being met at the mine. Air quality impacts would cease to occur after 

mining and reclamation are complete. The cumulative effects that would increase the potential for 

acidification of lakes resulting from the Proposed Action are expected to be minor but extended

to 2031. Air quality impacts from the SCM would cease to occur after mining and reclamation are 

completed.

4.4.4.3 Mitigation Measures

No mitigation measures beyond those required by the SCM air quality permit would be required 

for visibility.

4.4.5 Greenhouse Gas Emissions

4.4.5.1 Direct and Indirect Effects of the Proposed Action

4.4.5.1.1 Proposed Action

OSMRE has elected to quantify direct and indirect GHG emissions and evaluated these emissions 

in the context of national GHG emission inventories based on 100-year and 20-year time horizons. 

In addition, direct and indirect GHG emissions are evaluated in the context of state, national, and 

global GHG emission inventories. Each GHG has a different lifetime in the atmosphere and a 

different ability to trap heat in the atmosphere. To allow different gases to be compared and added 

together, emissions can be converted into CO2e emissions. Annual CO2e emissions from 

combined sources, based on the average annual coal recovered between 2014 and 2018 at the 

SCM, were estimated (section 3.4.1.5). The same variables were used to calculate annual CO2e 

emissions for 2020-2031. 

As presented in table 4-3, the estimated annual CO2e emissions from coal mined between 2020 

and 2031 would be the slightly higher (0.35 percent) than estimated annual emissions between 

2014 and 2018. The increase in estimated emissions is related to the distance used to calculate 

transportation emissions (per-trip weighted average of 1,144 rail miles for the 2014-2018 time 

frame versus per-trip weighted average of 1,210 for the 2020-2031 time frame).
Chapter 4 – Environmental Consequences/Cumulative Effects

4-12 Spring Creek Mine TR1 EA

Table 4-3. Estimated Annual CO2e Emissions for the Proposed Action from Coal 

Mined at the SCM (2014-2018 Average and 2020-2031 Average) Under 

100-year and 20-year Time Horizons

100-year Time Horizon

Source 2014-2018 Average 

Annual Emissions

2020-2031 Average 

Annual Emissions

General

Mt tons of coal recovered 14.21 14.20

Average transport miles (one way) 1,144 1,210

Number of train trips (loaded and returning empty) 1,822 1,820

Vessel transport miles (one-way) 4,300 4,300

Direct emission sources1

Fuel 27,910 27,882

Electricity consumed in mining process 45,322 45,276

Mining process 8,208 8,200

Total direct emissions 81,440 81,357

Indirect emission sources1

Transport 931,448 1,040,517

From coal combustion229,792,278 29,792,278

Total indirect emissions 30,723,727 30,832,796

Total estimated CO2e production1 30,805,167 30,914,153

20-year Time Horizon

Source 2014-2018 Average 

Annual Emissions

2020-2031 Average 

Annual Emissions

General

Mt tons of coal recovered 14.21 14.20

Average transport miles (one way) 1,144 1,210

Number of train trips (loaded and returning empty) 1,822 1,820

Vessel transport miles (one-way) 4,300 4,300

Direct emission sources1

Fuel 28,052 28,024

Electricity consumed in mining process 45,553 45,506

Mining process 8,250 8,241

Total direct emissions 81,855 81,771

Indirect emission sources1

Transport 936,188 1,045,812

From coal combustion229,943,871 29,943,871

Total indirect emissions 30,880,058 30,989,683

Total estimated CO2e production1 30,961,913 31,071,454

1

In metric tons - see appendix B for calculations

2 Calculated by WWC (2019)

According to the EPA (2019d) in 2017 (the most recent year of available CO2 data at this time), 

estimated CO2e emissions from fossil-fuel combustion in the U.S. totaled 4,912 million metric tons 

in 2017. Using the 2017 U.S. estimate for comparison purposes, the estimated annual 100-year 

CO2e contribution from the Proposed Action would be 30.9 million metric tons, or approximately 

0.63 percent of the 2017 U.S. total. According to the IPCC 2014 Climate Change Synthesis Report, 

the estimated total 2010 global CO2e emissions totaled 49,100 million metric tons. The IPCC 

report estimated that approximately 78 percent (i.e., 38,298 million metric tons) of the total 

global CO2e emissions are from fossil fuel combustion. Using the 2010 global estimate for 

comparison purposes, the estimated annual 100-year CO2e contribution from the Proposed 
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-13

Action would be 30.9 million metric tons, or approximately 0.081 percent of the 2010 global fossil 

fuel emissions. The direct and indirect effects of the Proposed Action on annual CO2e emissions 

would be moderate but they would be extended by approximately 4 years, to 2031.

The direct and indirect effects of the Proposed Action on annual CO2e emissions would be 

moderate but they would be extended by approximately 4 years, to 2031.

4.4.5.1.2 No Action Alternative

The impacts directly resulting from GHG emissions under the No Action Alternative would be 

less than those under the Proposed Action and would not be extended to 2031.

4.4.5.2 Cumulative Effects

The analyses provided above include direct and indirect effects analysis for GHG emissions. 

Emissions of GHGs resulting from the Proposed Action would increase the atmosphere’s 

concentration of GHGs, and in combination with past, present, and future emissions from all other 

sources, they would contribute incrementally to the global warming that produces the adverse 

effects of climate change described previously. 

However, the climate change research community has not yet developed tools for evaluating or 

quantifying endpoint impacts attributable to the emissions of GHGs from a single source. The 

current tools for simulating climate change generally focus on global and regional-scale modeling; 

therefore, a separate cumulative impacts analysis for GHG emissions at the project level would 

not provide useful information for the decision maker and was not prepared.

4.4.5.3 Mitigation Measures

No mitigation measures have been defined for GHG emissions.

4.4.6 Climate Change Cause and Effect

4.4.6.1 Direct and Indirect Effects of the Proposed Action

4.4.6.1.1 Proposed Action

Although the effects of GHG emissions and other contributions to climate change in the global 

aggregate are estimable, it is currently not feasible to determine what effect GHG emissions in a 

specific area resulting from a specific activity might have on climate change or to determine the 

resulting environmental impacts in a quantitative manner. 

The electric power sector is the largest consumer of coal in the U.S., with coal accounting for 93 

percent of all coal consumed for energy in the United States in 2017. However, the amount of 

coal and the percent of total electricity generation from coal has been decreasing over time. Coalfired electric generation (in kilowatt-hours [kWh]) decreased from 54 percent of generation in 

1990 to 31 percent in 2017 (EPA 2019b). The combustion of coal for the generation of electricity 

does contribute to GHG emissions and table 4-4 shows the U.S., regional, and local trend in 

GHG emissions between 2005 and 2017 (the most recent EPA data available). Table 4-4 also 

shows the trend in global GHG emissions (including a sperate row for China). It is important to 

note that while global GHG emissions have increased over time, the U.s and regional GHG 

emissions have decreased significantly.
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4-14 Spring Creek Mine TR1 EA

Table 4-4. Trends in Global, U.S., Regional, and Local GHG Emissions and 

Contributing Factors

Gas/Source 2005 2017 Percent 

Change

Contributing Factors (Mt)

Coal Produced in the U.S. 1,164.5 767.7 -34.1

Coal Produced in Montana PRB 40.3 34.5 -14.4

Coal produced at the SCM 13.1 12.7 -3.1

Global GHG Emissions (Million Metric Tons CO2e)

Total GHG emissions 44,153 53,500 21.2

GHG emissions from fossil fuel 29,912 37,180 24.3

China GHG emissions from fossil fuel 6,265 11,877 129.9

U.S. GHG Emissions (Million Metric Tons CO2e)

Total GHG emissions 7,339.0 6,456.7 -12.0

GHG Emissions from power generation 2,450.4 1,772.7 -27.7

GHG emissions from coal-fired power generation 2,430.9 1,757.9 -27.7

Montana GHG Contributions (Million Metric Tons)

GHG emissions from fossil fuels (CO2 Only) 34.9 30.3 -13.2

SCC GHG Contributions (Million Metric Tons)

GHG emissions from combustion of SCC coal 27.4 26.7 -2.6

Source: EPA 2019b, USEIA 2006 and 2018

As concluded from the information presented above, Montana PRB surface coal mines were 

responsible for approximately 64.1 million metric tons of the estimated U.S. CO2e emissions from 

fossil-fuel combustion for power generation in 2017. The coal mined at the SCM resulted in about 

23.1 million metric tons (1.3 percent) of the estimated 2017 U.S. CO2 emissions from coal power 

generation. In 2017, approximately 134,000 tons (1.0 percent) of coal mined at the SCM was 

burned in Montana power plants (SCC 2019). Information included in Montana’s CCAP estimated 

that approximately 15.2 Mt of GHG were emitted in 2010 (the most current Montana GHG 

emission estimates available) to generate electricity or from the fossil fuel industry (CCAC 2007). 

Using these numbers, it is estimated that the coal from the SCM that was burned in Montana 

power plants in 2010 accounted for approximately 80,560 tons of GHG.

As stated above, estimated CO2 emissions in the U.S. decreased 12.0 percent from 2005 to 2017 

(EPA 2019b). Under the Proposed Action, coal production has been evaluated at 14.2 Mtpy levels, 

using existing production and shipping methods. As determined from table 4-3, the estimated 

annual CO2e emissions from coal mined at the SCM under the 100-year time horizon would be 

approximately 30.9 million metric tons for the 4 additional years. Because CO2 emissions have 

been declining in recent years and because CO2 from coal mined at the SCM would remain at or 

only slightly above current levels, climate impacts associated with direct/indirect emissions from 

TR1 Tract mining, transportation, and combustion would be moderate but short term (4 years).

4.4.6.1.2 No Action Alternative

The impacts from GHG emissions under the No Action Alternative would be similar to those 

under the Proposed Action but would not be extended by approximately 4 years. While annual 

CO2e emissions would remain the same as the Proposed Action for approximately 5.3 years, the 

LOM CO2e emissions would decrease by approximately 30.9 million metric tons as a result of the 

No Action Alternative, based primarily on 4 fewer years of combustion of SCM coal. 

4.4.6.2 Cumulative Effects of the Proposed Action

The human and natural causes of climate change, and the impacts of climate change, are global. 

GHG emissions do not remain localized but become mixed with the general composition of the 
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Spring Creek Mine TR1 EA 4-15

Earth’s atmosphere. On a global scale, the GHG emissions contribution of any single geographic 

subunit (such as a SMCRA-delegated state regulatory authority or OSMRE regional office) or 

source (such as Federal minerals) on a subnational scale is dwarfed by the large number of 

comparable national and subnational contributors. The relative contribution of GHG emissions 

from production and consumption of Federal minerals will vary depending on contemporaneous 

changes in other sources of GHG emissions. A single subnational contributor is very unlikely to 

influence global cumulative emissions. Therefore, this analysis does not separate the particular 

contribution of the Proposed Action’s GHG emissions to global climate change impacts from the 

multitude of other past, present, and RFFAs that have produced or would produce or mitigate 

GHG emissions. At present, the climate change research community has not yet developed tools 

for evaluating or quantifying endpoint impacts attributable to the emissions of GHGs from a single 

source. The current tools for simulating climate change generally focus on global and regional-scale 

modeling.

Cumulative climate change effects from future coal mining and coal combustion are difficult to 

quantify due to market and regulatory forces that affect the amount of coal produced and the use 

of coal for U.S. electricity generation. For example, recent increasing supplies of natural gas has 

led to a decline in the cost of natural gas, making coal less competitive based on price and 

regulatory conditions have also affected the coal industry (Wyoming Mining Association 2017). As 

a result, U.S. electricity generation from coal-fired power plants has declined and is expected to 

continue to decline. From 2005 to 2017, GHG emissions from U.S. power plants decreased 

approximately 13 percent (EPA 2019b). However, some generalizations of effects can be made.

The USGS has produced estimates of the GHG resulting from the extraction and end-use 

combustion of fossil fuels produced on federal lands in the United States, as well as estimates of 

ecosystem carbon emissions and sequestration on those lands (Merrill et al. 2018). The study 

reports GHG emissions from extraction, transport, fugitives, and combustion of fuel over a 

10-year period (2005-2014). In 2014, nationwide gross GHG emissions (CO2, CH4, and N2O

combined) from fossil fuels extracted from federal lands was 1,332.1 million metric tons CO2e. 

Emissions from fossil fuels produced on federal lands represent, on average, 23.7 percent of 

national emissions for CO2, 7.3 percent for CH4, and 1.5 percent for N2O over the 10 years,

included in USGS estimate (Merrill et al. 2018). Trends and relative magnitude of emissions are 

roughly parallel to production volumes. Montana federal fossil-fuel-related gross emissions in 2014 

were 43.5 million metric tons of CO2e, approximately 3.3 percent of the estimate of national 

emissions from federal fossil fuels. 

The linear trend of the USGS data shows a decrease of 0.7 million metric tons CO2e/yr in Montana 

between 2005 and 2014. Assuming this trend continues, projected Montana federal fossil fuel 

emissions in 2031 would be 31.2 million metric tons CO2e. Estimated lease sale emissions between 

2020 and 2031would add to the USGS calculated emissions by 421.8 million metric tons CO2e. 

Federal lands also uptake carbon in vegetation, soils, and water. In 2014, carbon storage on federal 

lands was 83,600 million metric tons CO2e nationally and 6,230 million metric tons CO2e in 

Montana. Soils stored 57.5 percent of carbon with dead organic matter and vegetation and storing 

13.2 percent and 2.8 percent, respectively. The national rate of net carbon uptake (sequestration) 

varies from 51 million metric tons CO2e/yr to 475 million metric tons CO2e/yr to due to changes 

in climate/weather, land use, land cover change, wild fire frequency, and other factors. From 2005 

to 2014, terrestrial ecosystems on federal lands sequestered an average of 195 million metric tons 

CO2e/yr, offsetting about 15 percent of emissions resulting from federal fossil fuel extraction and 
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4-16 Spring Creek Mine TR1 EA

combustion nationally. In Montana, the annual average ecosystem carbon storage was 6,141.4

million metric tons CO2e, with soils accounting for about 58.0 percent. The annual average 

sequestration in Montana over the 10 years was 18.9 million metric tons CO2e/yr, offsetting about 

43.5 percent of extraction and combustion emissions from fossil fuels produced on federal lands 

in Montana. 

Electricity generation has accounted for approximately 28 percent of U.S. GHG emissions 

(EPA 2019b). However, state and federal regulations will decrease GHG emissions from power 

plants. And as of January 2013, 29 states had a renewable portfolio standard, which requires 

utilities to supply a certain amount of electricity to customers from renewable energy sources or 

install a certain amount of electricity-generating capacity from renewable energy sources in a set 

time frame (U.S. Department of State 2014). In addition, the EPA recently proposed three new 

regulations to reduce CO2 emissions from new, existing, and modified or reconstructed power 

plants (U.S. Senate 2015). Montana has formulated a climate action plan that evaluated GHG 

reduction opportunities in various sectors of Montana’s economy (CCAC 2007). Montana’s 

climate action plan provided recommendations, including the fossil fuel production sector, to 

reduce GHG emissions in the state over the period from 2007 through 2020 and their respective 

net costs or benefits on a cost-effectiveness (i.e., cost-per-ton-reduced) basis (CCAC 2007).

Social Cost of Carbon

A protocol to estimate what is referenced as the social cost of carbon (SCC) associated with GHG 

emissions was developed by a Federal interagency working group1 to assist Federal agencies in 

addressing EO 12866, Regulatory Planning and Review, which requires the assessment of the cost 

and the benefits of proposed regulations as part of their regulatory impact analyses. The SCC is an 

estimate of the economic damages associated with an increase in CO2 emissions and is intended to 

be used as part of a cost-benefit analysis for proposed rules. As explained in the Executive Summary 

of the 2010 SCC Technical Support Document, “the purpose of the [SCC] estimates . . . is to allow 

agencies to incorporate the social benefits of reducing carbon dioxide (CO2) emissions into costbenefit analyses of regulatory actions that have small, or ‘marginal,’ impacts on cumulative global 

emissions” (Interagency Working Group on the Social Cost of Carbon 2010). While the SCC 

protocol was created to meet the requirements for regulatory impact analyses during rulemakings, 

there have been requests by public commenters or project applicants to expand the use of SCC 

estimates to project-level NEPA analyses.

The decision was made not to expand the use of the SCC protocol for the Federal coal tracts for 

a number of reasons. Most notably, this action is not a rulemaking for which the SCC protocol 

was originally developed. 

1 On March 28, 2017, President Donald Trump issued EO 13783, which, among other actions, withdrew the technical 

support documents upon which the protocol was based and disbanded the earlier Interagency Working Group on 

the Social Cost of Greenhouse Gases. The EO further directed agencies to ensure that estimates of the social cost 

of GHGs used in regulatory analyses “are based on the best available science and economics” and are consistent 

with the guidance contained in the U.S. Office of Management and Budget (OMB) Circular A-4, “including with 

respect to the consideration of domestic versus international impacts and the consideration of appropriate discount 

rates” (EO 13783, Section 5(c)). In compliance with OMB Circular A-4, interim protocols have been developed for 

use in the rulemaking context; however, OMB Circular A-4 does not apply to project decisions, so there is no EO 

requirement to apply the SCC protocol to project decisions.
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Spring Creek Mine TR1 EA 4-17

Further, NEPA does not require a cost-benefit analysis (40 CFR 1502.23), although it does require 

consideration of “effects” that include “economic” and “social” effects (40 CFR 1508.8(b)). 

Without a complete monetary cost-benefit analysis, which would include the social benefits of the 

Proposed Action to society as a whole and other potential positive benefits, sole inclusion of an 

SCC cost analysis would be unbalanced, potentially inaccurate, and not useful in facilitating an 

authorized officer’s decision. Any increased economic activity, in terms of revenue, employment, 

labor income, total value added, and output, that is expected to occur with the Proposed Action 

is simply an economic impact rather than an economic benefit, in as much as such impacts might 

be viewed by another person as negative or undesirable due to potential increases in local 

population, competition for jobs, and concerns that changes in population would change the quality 

of the local community. Economic impact is distinct from economic benefit as defined in economic 

theory and methodology, and the socioeconomic impact analysis required under NEPA is distinct 

from cost-benefit analysis, which is not required.

Finally, the SCC protocol does not measure the actual incremental impacts of a project on the 

environment and does not include all damages or benefits from carbon emissions. The SCC 

protocol estimates economic damages associated with an increase in CO2 emissions—typically 

expressed as a 1 MT increase in a single year—and includes, but is not limited to, potential changes 

in net agricultural productivity, human health, and property damages from increased flood risk 

over hundreds of years. The estimate is developed by aggregating results “across models, over 

time, across regions and impact categories, and across 150,000 scenarios” (Rose et al. 2014). The 

dollar cost figure arrived at based on the SCC calculation represents the value of damages avoided 

if, ultimately, there is no increase in carbon emissions. But the dollar cost figure is generated in a 

range and provides little benefit in assisting the authorized officer’s decision for project-level 

analyses because it is too uncertain. For example, in a previous EIS, OSMRE estimated that the 

selected alternative had a cumulative SCC ranging from approximately $4.2 billion to $22.1 billion 

depending on dollar value and the discount rate used. The cumulative SCC for the No Action 

Alternative ranged from $2.0 billion to $10.7 billion. 

Given the uncertainties associated with assigning a specific and accurate SCC resulting from 4 

additional years of operation under the mining plan modification, and that the SCC protocol and 

similar models were developed to estimate impacts of regulations over long time frames, OSMRE’s 

ability to evaluate these impacts on a project-level would be doubtful2 (Anthoff and Tol 2013; 

2

This conclusion is supported in the February 2018 BLM Regulatory Impact Analysis for the Proposed Rule to Rescind 

or Revise Certain Requirements of the 2016 Waste Prevention Rule (BLM 2018), noting that “[t]he scientific and 

economics literature has further explored known sources of uncertainty related to estimates of the social cost of 

carbon and other greenhouse gases noting further that researchers have examined the sensitivity of Integrated 

Assessment Models (IAMs) and the resulting estimates to different assumptions embedded in the models (e.g., 

Pindyck 2013; Hope 2013; Anthoff and Tol 2013; Nordhaus 2014; Waldhoff et al. 2011, 2014). The BLM further spoke 

to the “additional sources of uncertainty that have not been fully characterized and explored due to remaining data 

limitations”, concluding that ”[a]dditional research is needed to expand the quantification of various sources of 

uncertainty in estimates of the social cost of carbon and other greenhouse gases (e.g., developing explicit probability 

distributions for more inputs pertaining to climate impacts and their valuation).” The BLM further states, “[o]n 

damage functions, other experts have found that those used in most IAMs have no theoretical or empirical 

foundation, claiming that the overall model is able to “obtain almost any result one desires (Pindyck 2013). Naturally, 

the indeterminate amount of uncertainty surrounding the IAMs used to approximate social costs for specific 

greenhouse gas emissions merits additional research and analysis and further peer-review in order to better 
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4-18 Spring Creek Mine TR1 EA

Hope 2013; Nordhaus 2014; Pindyck 2013; Waldhoff et al. 2011, 2014). Without a complete 

monetary cost-benefit analysis, which would include the social benefits of the Proposed Action to 

society as a whole and other potential positive benefits, inclusion solely of an SCC cost analysis 

would be unbalanced, potentially inaccurate, and not useful in facilitating an authorized officer’s 

decision. 

To summarize, this EA does not undertake an analysis of SCC because 1) it is not engaged in a 

rulemaking for which the protocol was originally developed; 2) NEPA does not require costbenefit analysis and one has not been conducted here; and 3) the full social benefits of coal-fired 

energy production have not been monetized, and quantifying only the costs of GHG emissions, 

but not the benefits, would yield information that is both potentially inaccurate and not useful. On 

a global scale, the GHG emission contribution of any single geographic subunit (such as a SMCRAdelegated state regulatory authority or OSMRE regional office) or source (such as Federal 

minerals) on a subnational scale is dwarfed by the large number of comparable national and 

subnational contributors. The relative contribution of GHG emissions from production and 

consumption of Federal minerals will vary depending on contemporaneous changes in other 

sources of GHG emissions. A single subnational contributor is very unlikely to influence global 

cumulative emissions. See Section 4.4.6.1 for more details.

Given the uncertainties associated with assigning a specific and accurate social cost of carbon

estimate resulting from 4 additional years of operation under the mining plan modification, and 

that the social cost of carbon protocol and similar models were developed to estimate impacts of 

regulations over long time frames, this EA quantifies direct and indirect GHG emissions and 

evaluates these emissions in the context of Montana and U.S. GHG emission inventories, as 

discussed in section 4.4.6.1.

4.4.6.3 Direct and Indirect Cumulative Effects on the Proposed Action/No Action 

Alternative

Climate impacts and trends tend to be realized at local levels but a lack of reliable projections of 

climate change at the local level remains an impediment (USGCRP 2018). Therefore, the direct 

and indirect effects on the Proposed Action/No Action Alternative related to climate change will 

be discussed on a regional (county and state) scale.

The Fifth Assessment Report of the IPCC (AR5) includes a summary of data from 30 different 

global climate models that evaluate the natural systems and feedback mechanisms contributing to 

climate variability. A range of global GHG emissions scenarios known as representative 

concentration pathways (RCP) were considered in the modeling analysis to assess potential degrees 

of climate change impacts. A stringent mitigation scenario (RCP2.6), a low emissions scenario 

(RCP4.5), an intermediate emissions scenario (RCP 6.0), and an aggressive emissions scenario 

(RCP8.5) were evaluated in the report. These scenarios correspond to atmospheric concentrations 

of CO2 by the year 2100 of 421 ppm for RCP2.6, 538 ppm for RCP4.5, 670 ppm for RCP6.0, and 

936 ppm for RCP8.5. The range of likely change in global surface temperature by 2050 ranges from 

0.3 to 1 degree Celsius for the RCP2.6 scenario and from 0.5 to 2.0 degrees Celsius for the RCP8.5 

scenario. Generally, the more stringent climate change mitigation, the lower the projected change 

in global surface temperatures. When discussing regional impacts, however, it is important to note 

ascertain the best available science and economics in accordance with E.O. 13783.” The BLM’s discussion is in the 

context of a rulemaking for which the SCC was developed. The uncertainties regarding the applicability of the social 

cost of carbon by OSMRE in the context of a specific project is even greater.
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-19

that degrees of surface temperature increases vary from region to region. To discuss the cumulative 

impacts of GHG emissions for the project area, regional-scale projected impacts are discussed for 

the state of Montana. The USGS National Climate Change Viewer (USGS 2019) can be used to 

evaluate potential climate change at the state level. The viewer provides data showing projections 

of future climate trends under RCP emission scenarios RCP4.5 and RCP8.5. Data presented in the 

USGS Climate Change Viewer data can also be extrapolated to get a general understanding of 

impacts under RCP2.6 and RCP6.0. Generally, the RCP2.6 scenario can be assumed to contribute 

to a lesser degree of climate change impacts in the region, while the RCP6.0 can be assumed to 

contribute to impacts that are of lesser magnitude than RCP8.5 but of greater magnitude than 

RCP4.5. Projected changes to the maximum and minimum temperature and precipitation for Big 

Horn County, MT are presented for RCP4.5 and RCP8.5 to assess regional cumulative impacts 

from GHG emissions in Table 4-5, below. The RCP4.5 and RCP8.5 scenarios forecast similar levels 

of climate impacts in the region over the next few decades; however, impacts over the next century 

diverge significantly. Because of uncertainties in the climate models, especially toward the end of 

the century, the impacts projected represent a forecast but are not certain to occur at the 

magnitudes projected.

USGS predicted potential impacts for Montana and Big Horn County, Montana between 1981 and 

2010 versus between 2025 and 2049 using a moderate climate change scenario (RCP4.5, which 

assumes GHG concentrations are stabilized) and an aggressive climate change scenario (RCP8.5, 

which assumes no new climate change regulations or reductions would be implemented) (USGS

2019). In addition, BLM prepared the Northwest Plains Rapid Ecoregional Assessment (REA) to 

predict future climate change conditions, including the region of Montana that contains the SCM, 

for a variety of elements (BLM 2012).

The potential climate change impacts for the State of Montana and Big Horn County, Montana 

evaluated by the USGS are included in table 4-5. Since the Proposed Action would extend the

SCM LOM 4 years (to 2031), the Proposed Action would not contribute to the full extent of these 

potential climate change impacts. However, for analysis purposes, the EA assumes that the 

maximum impacts would be realized during the life of the mine.

Table 4-5. The Potential Climate Change Impacts in Montana and Big Horn 

County, Montana for Various Data Variables

Climate Indicator Variable Montana Big Horn County

Maximum Temperature Departure ( ̊F) – RCP4.5 2.9 2.9

Maximum Temperature Departure ( ̊F) – RCP8.5 3.2 3.2

Precipitation Departure (Inches) – RCP4.5 0.0 0.0

Precipitation Departure (Inches) – RCP8.5 0.0 0.0

Runoff Amount Departure (Inches/month) – RCP4.5 0.0 0.0

Runoff Amount Departure (Inches/month) – RCP8.5 0.0 0.0

Snow Water Equivalent Departure (Inches) – RCP4.5 -0.3 -0.1

Snow Water Equivalent Departure (Inches) – RCP8.5 -0.3 -0.1

Soil Water Storage Capacity Departure (Inches) – RCP4.5 0.0 0.0

Soil Water Storage Capacity Departure (Inches) – RCP8.5 0.0 0.0

Evaporation Deficit Departure (Inches/month) – RCP4.5 0.1 0.2

Evaporation Deficit Departure (Inches/month) – RCP8.5 0.1 0.1

Source: USGS 2019
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4-20 Spring Creek Mine TR1 EA

Hydrology

The potential changes to the annual snowfall, precipitation levels, and streamflow could impact 

area surface water body levels, groundwater recharge, and soil erosion. During the anticipated 

4-year life of the project, natural variations results in dryer or wetter years. Considering the overall 

climate change timeframe of centuries, it is possible that decreased snowpack may be observable 

locally or may not during the project timeframe. Likewise, decreases in streamflow may be 

observed, but during the mining dewatering timeframe of 4 years, mine dewatering may 

compensate for climate change related streamflow reduction, or may have no additional influence 

on streamflow. The potential climate change impacts predictions included in table 4-5 indicate 

that precipitation and runoff will not likely change as a result of climate change through 2049. 

Therefore, there will be no climate change impacts on streamflows where project impacts occur 

or they may be negligible during the project timeframe. The Proposed Action would have 

moderate, short-term impacts to surface water bodies and groundwater; however, the impact 

from changes to these resources based on climate change would be negligible and long term. 

Soils

The Proposed Action would involve disturbance of approximately 728.4 acres not currently 

approved under SCM’s current federal mining plan. As described in section 4.8.1.1, the direct 

and indirect effects related to the Proposed Action to soils would be moderate but extended to 

2031 on the tract. However, the USGS climate viewer does not predict any annual mean changes 

to runoff so there would be negligible impacts on soils from climate change. 

Greater Sage Grouse

The Proposed Action is consistent with MFWP’s MGRSG Advisory Council guidance (MGRSG 

Advisory Council 2014) and BLM’s Approved Resource Management Plan (BLM 2015), which take 

into account potential climate change. Impacts from climate change on the GRSG during the life 

of the project are anticipated to be negligible. In addition, the BLM evaluated the potential impacts 

of climate change on Greater sage-grouse in the Northwestern Plains Rapid Ecoregional 

Assessment (REA) for the period between 2050 and 2069 (BLM 2012). The REA indicated that 

Greater sage-grouse would be moderately vulnerable to the impacts of climate change during the 

period. However, it remains difficult to draw conclusions from the data presented in the REA as 

the climate change models are highly variable and often difficult to predict (BLM 2012).

Reclamation

The post-reclamation land use would be wildlife habitat and grazing, consisting of vegetation cover 

of grasses and shrubs. Potential changes to the natural environment, as listed above, could result 

in the need to consider different plant species during reclamation to account for the higher 

temperatures and increased precipitation levels. MDEQ regulates surface coal mining operations

and the surface effects of underground coal mining on federal lands within the state of Montana. 

Federal coal leaseholders in Montana must submit a permit application package to OSMRE and 

MDEQ for any proposed revisions to reclamation operations on federal lands in the state. 

Therefore, any change to reclamation practices (i.e., seed mix) at the SCM would require the 

approval of MDEQ. Climate change impacts on reclamation during the life of the project would be 

negligible. Reestablishment of wildlife and vegetation in areas that have been disturbed is reliant 

on the reclamation process which would be negligibly impacted by climate change; therefore, 

climate change impacts to wildlife and vegetation in reclaimed areas would be negligible and long

term.
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Spring Creek Mine TR1 EA 4-21

4.5 Water Resources

4.5.1 Groundwater

4.5.1.1 Direct and Indirect Effects 

4.5.1.1.1 Proposed Action

Additional discussions regarding groundwater can be found in sections 3.5.1 and 4.1.4 of the 2010 

LBM EA and the groundwater portion of the 2020 CHIA (MDEQ-WQD 2020). The groundwater 

portion of the 2020 CHIA evaluated mining south of the Pearson Creek drainage, including the 

TR1 Tract. Under the Proposed Action, mining of the TR1 Tract would extend the area of coal 

removal onto approximately 498.1 acres of federal surface. Additionally, approximately 728.4 acres 

of surface disturbance would occur under the Proposed Action to recover the federal coal.

The general impacts to groundwater as a result of surface coal mining include the following:

• The removal of the uppermost coal aquifer and the much smaller, largely discontinuous 

overburden and alluvial aquifers within the areas that are mined would continue. The 

uppermost coal aquifer would be replaced with backfilled overburden material; this 

post-mine aquifer is expected to function similar to pre-mine conditions and meet 

existing groundwater uses in the area. This is based on groundwater modeling and 

ongoing aquifer recovery monitoring.

• In the short term, groundwater levels (quantity) within the mine area would be 

impacted through dewatering, but modeling indicates the aquifer (consisting of 

backfilled overburden material) would recover in the long term to pre-mine levels. 

Ongoing monitoring of the backfilled overburden aquifer indicates that recovery of this 

aquifer is occurring.

• The groundwater quality in the backfilled overburden aquifer would change when 

compared to the groundwater quality in the coal it replaced. The total dissolved solids 

concentrations in the backfill water is projected to reach maximum during initial 

saturation and then decrease to an equilibrium level after one or more pore volumes 

of water pass through the backfill. As re-saturation of the backfill continues, salt 

concentrations are expected to be extremely variable and peak at concentrations 

potentially two to three times that of the baseline coal groundwater quality and then 

decline to an equilibrium value after being flushed by one or more pore volumes of 

groundwater. Groundwater quality is expected to meet the existing uses (i.e., livestock 

watering) during all phases of mining and post-mining; this is supported by ongoing 

aquifer recovery monitoring inside and outside mine-affected areas.

Other groundwater impacts may or may not occur, or may occur only at specific locations, include 

changes in water quality (usually deterioration) outside the area that is mined and reclaimed. This 

would result from communication between the reclaimed aquifer and the unmined aquifer, and 

changes in recharge-discharge conditions and/or groundwater flow patterns.

Additional alluvial, overburden, and Anderson/Dietz coal aquifers would be removed within the 

TR1 Tract during the mining process. These aquifers would be replaced with backfilled overburden 

and interburden materials. The physical characteristics of the reclaimed backfill material are 

dependent upon mining methods and premining overburden lithology. Overall, the permeability 

and porosity of the spoils within the tract are expected to be greater than the original material. 

The reclaimed spoil aquifer could provide adequate water quantity for stock wells. Predicted 

drawdowns for the Anderson-Dietz; the D1, D1L, and D1U; and D2 and D3 aquifers are presented 

on maps 4-1, 4-2, and 4-3, respectively. 
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4-22 Spring Creek Mine TR1 EA

Map 4-1. Predicted Drawdown in the Anderson Dietz Aquifer
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Spring Creek Mine TR1 EA 4-23

Map 4-2. Predicted 10-Foot Drawdown in the D1, D1U, and D1L Aquifers
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4-24 Spring Creek Mine TR1 EA

Map 4-3. Predicted 10-Foot Drawdown in the D2 and D3 Aquifers
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Spring Creek Mine TR1 EA 4-25

The direct and indirect effects to groundwater resources resulting from the Proposed Action on 

the tract due to aquifer removal are expected to be moderate and short term (immediate effects 

from aquifer removal) and moderate and long term (related to reestablishing aquifer 

characteristics).

4.5.1.1.2 No Action Alternative

Impacts to groundwater under the No Action Alternative would be similar to those under the 

Proposed Action, but the aerial extent of groundwater aquifer removal would be reduced by 

approximately 728.4 acres. Impacts to overburden and coal aquifers have already occurred within 

the TR1 Tract related to coal recovery on adjacent federal coal leases, ongoing mining activities 

at nearby mines, and CBNG recovery. Under the No Action Alternative, the duration of impacts 

to groundwater would not be extended. Therefore, implementation of the No Action Alternative 

would have negligible effect on reducing the magnitude of these impacts, but would reduce the 

extent and duration.

4.5.1.2 Cumulative Effects

The effects of removal of the coal and overburden aquifers and replacing them with backfilled 

overburden are the foremost groundwater concern regarding cumulative effects. Mining of the 

TR1 Tract would increase the cumulative size of the backfill area in the Tongue River drainage 

basin. The extent of water level drawdown in the coal and shallower aquifers in the area 

surrounding the mines also would be expected to increase slightly as a result of mining in the tract 

and from dewatering the active mine pits. Where the effects of pumping from mines (e.g., Spring 

Creek, North, West and East Decker mines) overlap, additional water level declines result from 

concurrent operations. In 2020 MDEQ prepared a CHIA related to expanding mining at the SCM 

to the south into the Pearson Creek drainage (MDEQ-WQD 2020). The 2020 CHIA evaluated

impacts from mining at the SCM and the Decker Mine. MDEQ is in the process of preparing an 

updated CHIA but this document has not been made public and is not avail for inclusion into this 

EA. A main component of a CHIA is to determine if material damage would result from a proposed 

project. As defined at Montana Code Annotated (MCA) 82-4-203(30), material damage occurs if, 

outside of a permit boundary, land uses or beneficial uses of water are adversely affected, a water 

quality standard is violated, or if water rights are impacted. MDEQ concluded that no material 

damage was identified outside the permit boundaries of the Spring Creek or Decker Coal mines, 

and based on hydrologic analysis, no material damage was anticipated.

Mitigation Measures

Montana State regulations require surface coal mine permittees to replace any domestic, 

agricultural, industrial, or any other legitimate use groundwater supplies if, as a result of mining, a 

supply is diminished, interrupted, or contaminated, to the extent of precluding use of the water. 

The Montana State regulations also require surface coal mine permittees to restore the essential 

hydrologic function of disturbed land surfaces. According to MCA 82-4-203(30), proposed mining 

operations must be designed and conducted in a way to prevent material damage to the hydrologic 

balance outside the permit area (MCA 2015).
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4-26 Spring Creek Mine TR1 EA

4.5.2 Surface Water

4.5.2.1 Direct and Indirect Effects 

4.5.2.1.1 Proposed Action

Additional discussions regarding surface water can be found in sections 3.5.2 and 4.1.4 of the 2010 

LBM EA and the surface-water portion of the 2020 CHIA. 

The 2020 CHIA presents information that exceedances of MDEQ water standards from the Spring 

Creek/South Fork Spring Creek drainages, which includes the TR1 Tract, have occurred in samples 

from locations upstream and downstream of the mine. Exceedances of livestock thresholds in 

samples both upstream and downstream of mining in the Spring Creek drainage have also been 

noted. Baseline monitoring for the Pearson Creek drainage showed similar constituent 

concentrations. The 2020 CHIA also states that current mining operations at the SCM in the 

Spring Creek and South Fork Spring Creek drainages have not resulted in measurable changes in 

water quality.

Changes in surface runoff characteristics and sediment discharges would occur during mining on 

the tract because of the mining and reconstruction of drainage channels as mining progresses and 

because of the use of sediment control structures to manage discharges of surface water from the 

mine permit areas. According to MCA 82-4-203(30), proposed mining operations must be 

designed and conducted in a way to prevent material damage to the hydrologic balance outside 

the permit area (MCA 2015). While the entire disturbance area associated with the Proposed 

Action has been approved for disturbance under the recently approved TR1 MR for SMP 

C1979012, approximately 728.4 acres of surface disturbance are anticipated related to mining the 

federal coal within the TR1 Tract. However, reclamation would be ongoing and concurrent with 

mining so there would not be a significant increase in the size of the area that is disturbed at any 

given time. The direct and indirect effects to surface water would not be significantly different than 

those described in the 2010 LBM EA and are expected to be moderate but extended to 2031.

4.5.2.1.2 No Action Alternative

The impacts to surface water under the No Action Alternative would be similar in nature to those 

under the Proposed Action but the magnitude of the impacts would be reduced since disturbance 

to 728.4 acres to recover federal coal within the tract would not occur. Therefore, 

implementation of the No Action Alternative would have negligible effect on reducing the 

magnitude of surface water impacts.

4.5.2.2 Cumulative Effects

The cumulative impact area for potential surface water impacts includes proposed LOM 

disturbance area for the SCM and Decker Mine within local drainage basins, and the adjacent 

Tongue River Reservoir area. Mining related impacts to surface water are expected to be 

measurable in the short term within and below mined area drainages and would diminish with 

reclamation and distance downstream. MDEQ concluded in the 2020 CHIA that no material 

damage to surface-water systems would result from the mining evaluated in the CHIA.

4.5.2.3 Mitigation Measures

Montana State regulations require surface coal mine permittees to restore the essential hydrologic 

function of disturbed land surfaces. And, as stated above, proposed mining operations must be 
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-27

designed and conducted in a way to prevent material damage to the hydrologic balance outside 

the permit area (MCA 2015).

4.5.3 Water Rights

4.5.3.1 Direct and Indirect Effects 

4.5.3.1.1 Proposed Action

Prior to energy development in the area, water appropriations (both groundwater and surface 

water) were typically for livestock use. Currently, mining companies hold the majority of the water 

rights in the vicinity of the Proposed Action. According to MCA 82-4-203(30), proposed mining 

operations must be designed and conducted in a way to prevent material damage to the hydrologic 

balance outside the permit area (MCA 2015).

Monitoring wells are placed between mine operations and nearby private wells to monitor for 

water level and water quality changes to anticipate any downgradient impacts. Currently, CBNG 

production has exceeded the amount of drawdown predicted to result from mining. Therefore, 

potential impacts from mining to stock and domestic wells in the area have become largely 

irrelevant (MDEQ-WQD 2020).

Numerous livestock water wells have been removed over the years to facilitate mining operations 

but no effects to domestic supplies have been reported. No material damage has been identified 

outside the permit boundaries of the SCM or Decker Mine and, based on hydrologic analysis, no 

material damage to water rights is anticipated (MDEQ-WQD 2020).

In general, the proposed federal mining plan amendment would contribute to additional, more 

extensive mining disturbance that may impact groundwater and surface-water rights in the SCM

area. As stated in section 3.2.1, current groundwater conditions have already changed in the 

SCM area as a result of CBNG development and ongoing mining operations at the SCM and 

Decker Mine. Therefore, the Proposed Action would not result in substantial declines in the 

groundwater availability, due to reduced groundwater quantity and quality, over what is currently 

being experienced. In addition, only a slight reduction in streamflow downstream of the SCM 

during mining is expected because runoff is currently being controlled within the SCM as a result 

of mining unrelated to the Proposed Action and the Decker Mine currently intercepts all remaining 

flows from Spring Creek and Pearson Creek. Therefore, impacts to groundwater or surface-water 

rights have already occurred from mining within the SCM and implementation of the Proposed 

Action would have negligible effect on increasing the extent of impacts.

4.5.3.1.2 No Action Alternative

The impacts on water rights under the No Action Alternative would be similar in nature to those 

under the Proposed Action but the magnitude of the impacts would be reduced since disturbance 

to 728.4 acres to recover federal coal within the tract would not occur. Impacts to water rights 

have already occurred within the tract related to coal recovery on adjacent federal coal leases, as 

approved by SMP C1979012 and OSMRE’s 2012 federal MPDD. Therefore, implementation of the 

No Action Alternative would have negligible effect on reducing the magnitude of impacts on water 

rights.

4.5.3.2 Cumulative Effects

While the approval of the federal mining plan modification request would contribute to additional, 

more extensive mining disturbance in the SCM and Decker Mine areas, there would be minor 
Chapter 4 – Environmental Consequences/Cumulative Effects

4-28 Spring Creek Mine TR1 EA

additional cumulative water rights impacts because groundwater systems have already been 

affected by CBNG removal and ongoing mining and because runoff is currently being controlled in 

within the SCM and the Decker Mine currently intercepts all remaining flows from Spring Creek 

and Pearson Creek.

4.5.3.3 Mitigation Measures

Montana State regulations require surface coal mine permittees to replace any domestic, 

agricultural, industrial, or any other legitimate use groundwater supplies if such supplies are 

diminished, interrupted, or contaminated, to the extent of precluding use of the water as a result 

of mining. The regulations also require restoration of the essential hydrologic function of disturbed 

land surfaces.

4.6 Alluvial Valley Floors

4.6.1 Direct and Indirect Effects

4.6.1.1 Proposed Action

The direct and indirect effects to alluvial valley floors (AVF) would not be significantly different 

than those described in Section 4.1.5 of the 2010 LBM EA. No AVFs have been delineated within 

the tract so there would be no direct or indirect effects to AVFs from the Proposed Action.

4.6.1.2 No Action Alternative

Because no AVFs have been delineated within the tract, impacts to AVFs in the area under the No 

Action Alternative would remain as described in section 4.6.1.1.

4.6.2 Cumulative Effects

The cumulative effects to AVFs would not be significantly different than those described in the 

2010 LBM EA. One AVF has been delineated within the SCM permit boundary but it has been 

designated as insignificant to agriculture and is therefore not prohibited from mining. Much of this 

AVF has already been disturbed, as approved by SCC’s Pearson Creek Amendment for SMP 

C1979012 and OSMRE’s 2012 federal MPDD. No other AVFs have been delineated along the 

Spring Creek drainage system, above or below the SCM. As discussed in Appendix J of the mining 

permit for SMP C1979012, a hydrologic restoration plan has been developed that provides 

erosionally stable channels and floodplains following reclamation and plan calls for the restoration 

of the essential hydrologic functions, prevention of material damage, and re-establishment of the 

premining land usage of the hydrologic system of the South Fork Spring Creek.

4.6.3 Mitigation Measures

No mitigation measures would be necessary for AVFs.

4.7 Wetlands (Aquatic Resources)

4.7.1 Direct and Indirect Effects 

4.7.1.1 Proposed Action

No jurisdictional wetlands are present within the tract so there would be no direct or indirect 

effects to jurisdictional wetlands from the Proposed Action. Stock ponds and water impoundments 

with wetland soils, plants, and hydrology are present, but they are not considered jurisdictional 
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-29

because they either lack a continuous ordinary high-water mark or do not have a continuous 

nexus to other WOTUS.

4.7.1.2 No Action Alternative

No jurisdictional wetlands have been delineated within the tract so there would be no direct or 

indirect effects to jurisdictional wetlands from the No Action Alternative.

4.7.2 Cumulative Effects

While two delineated jurisdictional wetlands occur within the SCM permit boundary, no wetlands 

are present in the proposed tract. Cumulative impacts to jurisdictional wetlands would not be 

increased if the federal mining plan modification is approved. Wetlands disturbance within the 

SCM permit boundary are under the jurisdiction of the U.S. Army Corps of Engineers.

4.7.3 Mitigation Measures

No mitigation measures would be necessary for wetlands (aquatic resources).

4.8 Soil

4.8.1 Direct and Indirect Effects

4.8.1.1 Proposed Action

The direct and indirect effects to soils would not be significantly different than those described in 

Section 4.1.7 of the 2010 LBM EA. Soils of the tract would be altered under the Proposed Action. 

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. The 

direct and indirect effects related to the Proposed Action on soils would be moderate and short 

term.

4.8.1.2 No Action Alternative

The impacts to soils under the No Action Alternative would be similar in nature to those under 

the Proposed Action but the magnitude of the impacts would be reduced since disturbance to 

728.4 acres to recover federal coal within the tract would not occur.

4.8.2 Cumulative Effects

Following reclamation, the replaced topsoil should support a stable and productive native 

vegetation community adequate in quantity and quality to support planned post-mining land uses 

(i.e., rangeland and wildlife habitat). Areas within active mines are progressively disturbed. 

Likewise, these areas would be progressively reclaimed by planting appropriate vegetation species 

to restore soil productivity and prevent soil erosion. The cumulative effects related to soils would 

be moderate but extended to 2031.

4.8.3 Mitigation Measures

No mitigation measures would be necessary for soils resources.
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4-30 Spring Creek Mine TR1 EA

4.9 Vegetation

4.9.1 Direct and Indirect Effects

4.9.1.1 Proposed Action

The direct and indirect effects to vegetation would not be significantly different than those 

described in Section 4.1.8 of the 2010 LBM EA. Short-term impacts associated with the removal 

of vegetation from the TR1 Tract would include increased soil erosion and habitat loss for wildlife 

and livestock. Potential long-term impacts on reclaimed lands include loss of habitat or loss of 

habitat carrying capacity for some wildlife species as a result of reduced plant species diversity or 

plant density, particularly big sagebrush. However, livestock and grassland-dependent wildlife 

species would benefit from the increased grass cover and production.

Reclamation of disturbed lands with the SCM permit boundary is performed according to MDEQ 

regulatory standards (ARM 17.24.3). Reclamation would occur contemporaneously with mining 

on adjacent lands (i.e., reclamation would begin once an area is mined). In an effort to approximate 

premining conditions, SCC would plan to reestablish vegetation types during reclamation that are 

similar to the premine types. Reestablished vegetation would be dominated by species mandated 

in the reclamation seed mixtures (to be approved by MDEQ). The reclamation plan for the SCM 

includes steps to control invasion by weedy (invasive nonnative) plant species. While the entire 

disturbance area associated with the Proposed Action has been approved for disturbance by 

MDEQ under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres of 

surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. The 

direct and indirect effects related to the Proposed Action on vegetation would be moderate but 

extended to 2031.

4.9.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are related to mining the federal coal within the TR1 Tract. These acres 

would not be disturbed under the No Action Alternative. Under this alternative, impacts to 

vegetation in the area would remain as described in section 4.9.1.1, but the affected area would 

be reduced by 728.4 acres.

4.9.2 Cumulative Effects

The overall contribution to cumulative effects to vegetation under Proposed Action would be 

minor due to the localized effects and the improved productivity on mined lands that have been 

reclaimed.

4.9.3 Mitigation Measures

No mitigation measures would be necessary for vegetation resources.

4.10 Wildlife

The environmental consequences related to mining the TR1 Tract for other mammals; upland 

game birds (excluding the GRSG); other birds; and amphibians, reptiles, and aquatic species are 

not significantly different than those presented in Section 4.1.9 of the 2010 LBM EA and are not 

presented herein. Updated discussions for big game, raptors, GRSG, T&E species, and other 

species of special interest are included below.
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-31

4.10.1 Big Game

4.10.1.1 Direct and Indirect Effects 

4.10.1.1.1 Proposed Action

Under the Proposed Action, big game would be displaced from portions of the tract to adjacent 

ranges during mining. Mule deer would be most affected as the tract contains good quality habitat. 

Pronghorn would not be substantially impacted, because they are scattered throughout the site, 

and there is suitable habitat available in adjacent areas. White-tailed deer would not be affected, 

as they have not been observed on the tract. Big game displacement would be incremental, 

occurring over several years and allowing for gradual changes in distribution patterns. Big game 

residing in the adjacent areas could be impacted by increased competition with displaced animals. 

Noise, dust, and associated human presence would cause some localized avoidance of foraging 

areas adjacent to mining activities. However, big game species have continued to occupy areas 

adjacent to and within active mine operations at the SCM, suggesting that some animals may 

become habituated to such disturbances.

As determined from information from MFWP, no portion of the TR1 Tract disturbance area has

been designated as high value winter range for big game (MFWP 2016). Approximately 486.8 acres 

have been designated as moderate value winter range and the remaining 241.6 acres were 

designated by MFWP as not rated for winter range. SCM would be required to reclaim disturbed 

area back to wildlife habitat, as outlined in the reclamation requirements of revised state and 

federal mine permits. After mining and reclamation, alterations in the topography and vegetative 

cover, particularly the reduction in sagebrush density and loss of trees, would cause a decrease in 

carrying capacity and diversity on the tract. Sagebrush and trees would gradually become 

re-established on the reclaimed land, but the topographic changes would be permanent.

General reclamation practices for establishing or enhancing post‐mine wildlife habitat at the SCM 

are described in the Reclamation Plan (Section 17.24.313) of SMP C1979012. SCC also has 

developed a separate Habitat Recovery and Replacement Plan (HRRP) for the GRSG, which is a 

species of particular interest in the region. Because there is overlap between the big game winter 

range and the GRSG habitat areas, the reclamation of any GRSG habitat outlined the specific HRRP 

would fulfill the reclamation requirements for mule deer and pronghorn and would provide quality 

habitat for both big game and grouse that might be impacted by the Proposed Action. The direct 

and indirect effects related to the Proposed Action on big game would be moderate but extended 

to 2031.

4.10.1.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR to SMP C1979012, approximately 728.4 acres 

of surface disturbance are related to mining the federal coal within the TR1 Tract. These acres 

would not be disturbed under the No Action Alternative. Impacts to the big game species have 

resulted from current mining activity. Under this alternative, impacts to big game in the area would 

remain as described in section 4.10.1.1.1, but the affected area would be reduced by 728.4 acres 

and the duration of the effects would be shortened by 4 years.

4.10.1.2 Cumulative Effects

The regional EIS that covered the northern PRB (BLM 1984) predicted that large-scale surface 

coal mining could potentially result in significant cumulative effects to big game due to habitat loss; 
Chapter 4 – Environmental Consequences/Cumulative Effects

4-32 Spring Creek Mine TR1 EA

restrictions in seasonal and daily movement caused by railroads, access roads, and mining 

operations; poaching; urban development; range overuse; possible lack of water sources; increased 

road kills; and crop depredation. However, no severe mine-caused mortalities have occurred and 

no long-lasting impacts on big game species have been noted on the SCM. MFWP-designated high 

and moderate value winter range occurs in the area. The cumulative effects on regional big game 

population would be moderate but extended to 2031.

4.10.1.3 Mitigation Measures

No mitigation measures specific to big game would be necessary. General reclamation practices 

for establishing or enhancing post‐mine wildlife habitat at the SCM described in the Reclamation 

Plan (Section 17.24.313) of SMP C1979012 are in place. SCC also has developed a separate HRRP 

for the GRSG, which would provide quality habitat for big game.

4.10.2 Raptors

4.10.2.1 Direct and Indirect Effects 

4.10.2.1.1 Proposed Action

One intact raptor nest (TV2) is located within the disturbance area for the TR1 Tract. Although 

still intact, this nest has not been used since at least 1994. Vultures have been seen soaring within

the area in most years but no other intact nest sites have been found. This species is a migratory 

bird, which is protected under the MBTA (USFWS 2019b).

SCC has approved plans and procedures in place to minimize impacts to nesting raptors and 

ensure proper reclamation techniques are implemented to enhance habitat in the post-mine 

landscape for both raptors and their primary prey species. Inactive, non-eagle raptor nests may be 

removed from areas likely to be impacted in potential disturbance area to discourage nesting of 

raptors and other migratory birds, in accordance with USFWS guidance provided in the Migratory 

Bird Permit Memorandum (USFWS 2003). Decisions as to whether nest removal or relocation is 

the most appropriate approach would be based on the long-term history of the nest site including

historic and recent raptor use; presence/absence, location, and potential vulnerability of alternate 

nests within the territory; number, proximity, and/or orientation of conspecific territories; 

historical use of artificial nest structures, if any; timing, duration (e.g., continuous and ongoing or 

short term); proximity, and visibility of potentially disturbing mine activities; and other pertinent 

factors. In addition, SCC conducts annual surveys at multiple prairie falcon nest sites throughout 

the monitoring area and on neighboring lands as part of required and/or voluntary monitoring for 

this species.

Based on the limited number of nesting raptors within the proposed tract disturbance (only one 

known intact turkey vulture nest) and the SCC’s approved plans and procedures in place to reduce 

impacts to raptors, the direct and indirect effects related to the Proposed Action on site-specific 

raptors would be moderate but extended to 2031.

4.10.2.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. 

These acres would not be disturbed at this time under the No Action Alternative. Impacts to the 

raptors have resulted from current mining activity. Under this alternative, impacts to raptors in 
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-33

the area would remain as described in section 4.10.2.1.1, but the affected area would be reduced 

by 728.4 acres and the duration of the effects would be shortened by 4 years.

4.10.2.2 Cumulative Effects

Cumulative impacts to most raptors would increase as additional habitat is disturbed by mining 

and other activities. These impacts would be moderate but would improve as land is reclaimed. 

Approved mine permits include regulations specifying mitigation measures for wildlife, including 

minimization of disturbance, reclamation of habitats and raptor-safe power line construction. The

measures specified in mining permits and enforced by MDEQ ensure compliance with the 

Migratory Bird Treaty Act, the Bald and Golden Eagle Protection Act, and the ESA, thereby 

ensuring regional impacts to those protected wildlife species would be minor.

4.10.2.3 Mitigation Measures

No mitigation measures specific to raptors would be necessary. General reclamation practices for 

establishing or enhancing post‐mine wildlife habitat at the SCM described in the Reclamation Plan 

(Section 17.24.313) of SMP C1979012 are in place. SCC also has developed plans and procedures 

to minimize impacts to nesting raptors and ensure proper reclamation techniques are 

implemented to enhance habitat in the post-mine landscape for raptors and their primary prey 

species.

4.10.3 Greater Sage-Grouse (GRSG)

4.10.3.1 Direct and Indirect Effects 

4.10.3.1.1 Proposed Action

The SCM annual wildlife monitoring area includes five confirmed active lek sites, two confirmed 

inactive leks, one unconfirmed site, and one confirmed extirpated (mined through) lek. Long-term 

results from annual lek monitoring suggest that GRSG populations in the SCM annual wildlife 

monitoring area are cyclic, with periodic peaks and declines (Great Plains Consulting 2017). These 

data suggest that the SCM area may only support larger groups of GRSG when regional populations 

are especially high (Great Plains Consulting 2017).

To date, only the Upper Divide lek has been identified within the SCM permit area. It was eclipsed 

by mining operations in the early to mid-1980s. No other known GRSG leks would be physically 

disturbed by mine operations under the current SMP C1979012 LOM plan. The nearest active 

GRSG lek (Pasture Lek) is approximately 0.67 miles from the tract (map 3-5). Approximately 

3,013 non-contiguous acres in GRSG core area PRB-2 are within the current permit area (Great 

Plains Consulting 2017). Under the Proposed Action, approximately 728.4 acres of this core area 

would be affected.

SMP C1979012 currently contains multiple monitoring and protection plans that include numerous 

specific measures for GRSG and their habitats, including those mentioned above. The MDEQ has 

strict bonding, reclamation, and bond-release requirements for all surface coal mines in Montana, 

including detailed reclamation plans and post-reclamation monitoring requirements that extend 

10 years or more to ensure that all reclamation standards have successfully been met prior to full 

bond release. SCC’s development and implementation of a detailed HRRP for GRSG at the mine 

and its voluntary participation (through CPE) in the Thunder Basin Grasslands Prairie Ecosystem 

Association (TBGPEA) is intended to offset potential impacts to GRSG due to mine-related 

activities. TBGPEA works in collaboration and cooperation with a variety of government and 

non-government entities, as well as with experts in academia and members of the private sector 
Chapter 4 – Environmental Consequences/Cumulative Effects

4-34 Spring Creek Mine TR1 EA

to protect and enhance existing habitat for species of concern within the sagebrush steppe and 

the short-grass prairie ecotypes (TBGPEA 2019). 

Potential impacts to GRSG would likely be limited primarily to indirect influences resulting from 

habitat disturbance, though loss of individual birds may occur at times. Ongoing SCM operations 

may adversely impact individual GRSG but are not likely to result in a loss of population viability 

in the wildlife monitoring area or cause a trend toward federal listing. The use of appropriate 

timing and spatial buffers, timely implementation of reclamation, and application of targeted 

conservation measures in suitable habitats both on- and off-property throughout the region are 

expected to sufficiently reduce overall impacts to maintain a viable population within the area. The 

direct and indirect effects related to the Proposed Action on GRSG would be moderate but 

extended to 2031.

According to Executive Order No. 12-2015 (Amending and Providing for Implementation of the 

Montana Sage Grouse Conservation Strategy), existing land uses and activities (including those 

authorized by existing permit but not yet conducted) would be recognized and respected by state 

agencies, and those uses and activities that exist at the time the Program becomes effective would 

not be managed under the stipulations of the Montana Sage Grouse Conservation Strategy (Office 

of the Governor 2015). Approximately 707.5 acres (97.1 percent) of the disturbance associated 

with the Proposed Action is within the SCM’s currently approved SMP C1979012 permit

boundary, and these acres would not be managed according to the executive order. The remaining

20.9 acres (2.9 percent) of the proposed disturbance are outside of the currently approved permit 

boundary and would be subject to stipulations included in Executive Order No. 12-2015. 

Compliance with the stipulations in Executive Order No. 12-2015 are handled through the MDEQ 

permitting process and SCC would be required to address any stipulations relating to GRSG 

before disturbance would be allowed within the 20.9-acre parcel. As stated above, SCC has 

developed and implemented a detailed HRRP for GRSG at the mine and its voluntary participation 

in the TBGPEA to offset potential impacts to GRSG due to mine-related activities.

In addition, in fulfillment of MEPA and the Montana Strip and Underground Mine Reclamation Act 

(MSUMRA), SCC has developed general management and monitoring plans for wildlife species of 

interest that are part of SMP C1979012, as introduced in the TR1 MR EIS. The management and 

monitoring plans were developed through consultation with, and approval of the MDEQ, Montana 

Department of Fish, Wildlife and Parks (MDFWP), and the Montana Sage Grouse Habitat 

Conservation Program (MSGHCP).

4.10.3.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. 

These acres would not be disturbed at this time under the No Action Alternative. Impacts to the 

GRSG have resulted from current mining activity. Under this alternative, impacts to GRSG in the 

area would remain as described in section 4.10.3.1, but to a lesser extent.

4.10.3.2 Cumulative Effects

A conservation strategy was developed in collaboration with the USFWS, other state and federal 

agencies, and many other stakeholders in the region that would benefit numerous special interest 

species, including GRSG. SCC would implement a variety of conservation measures both on and 

off-property, with special emphases in habitats identified as Conservation Priority Areas (e.g., 
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-35

GRSG core areas, occupied short-grass prairie habitats, etc.) throughout the coverage area. These 

voluntary measures include a wide variety of land management actions that are designed to avoid 

or minimize impacts, and to restore, enhance, and/or maintain habitat benefiting one or more of 

the targeted species, including GRSG. Given these factors, ongoing cumulative energy development 

may adversely impact individual GRSG but are not likely to result in a loss of population viability 

in the wildlife monitoring area or cause a trend toward federal listing. The cumulative effects 

related to the Proposed Action on regional GRSG populations would be moderate but extended

to 2031.

4.10.3.3 Mitigation Measures

SCC has developed and implemented a detailed HRRP for sage-grouse at the mine and its voluntary 

participation in a large-scale conservation strategy highlighting sagebrush-steppe species across the 

region further offset potential impacts to sage-grouse due to mine-related activities. The plan is 

included in Section 17.24.312 of SMP C1979012 (SCC 2014). The HRRP consists of the following 

five parts:

• A habitat analysis of the permit areas. 

• A detailed description of the methods selected by the lessee to recover, replace or mitigate 

habitat loss, together with a comparative analysis of alternate methods which were 

considered and rejected by the lessee and the rationale for the decision to select the 

proposed methods.

• A timetable specifying that which will be required to accomplish the habitat recovery or 

replacement plan and showing how this timetable relates to the overall federal mining plan.

• An evaluation of the final plan by the BLM, in consultation with the State of Montana. 

• In the development of this plan, direct liaison with the State of Montana is essential.

Through CPE’s membership, SCC also is a voluntary participant in the TBGPEA. The focus if the 

association is to

• work in collaboration and cooperation with a variety of government and non-government 

entities, as well as with experts in academia and members of the private sector,

• develop and implement a strategy of adaptive management that is informed by and 

responsive to current conditions and the results of previously implemented conservation 

efforts,

• conduct extensive vegetation monitoring and targeted wildlife monitoring to support and 

enable adaptive management, and

• work with the USFWS to implement incentives based conservation strategy to protect 

eight species of concern that inhabit the sagebrush steppe and short-grass prairie of 

northeastern Wyoming.

If the Proposed Action is approved, SCC would be required to pay $107,727 in compensatory 

mitigation into the Montana Sage Grouse Oversight Team’s Stewardship Fund.

4.10.4 Threatened, Endangered, and Candidate (T&E) Species and Other Species 

of Special Interest (SOSI)

4.10.4.1 Direct and Indirect Effects 

4.10.4.1.1 Proposed Action

The current USFWS list of T&E species that may occur in Big Horn County, Montana includes the 

black-footed ferret (USFWS 2018). The black-footed ferret is listed as endangered for the SCM 
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4-36 Spring Creek Mine TR1 EA

area. Based on information in the USFWS’s (2013) recent update to the Black-footed Ferret Recovery 

Plan, the SCM is not located near an active or potential reintroduction area for this species. 

Because black-footed ferrets have not been documented in the area, there would be no effect to 

black-footed ferrets as a result of the Proposed Action.

For the purposes of this discussion, SOSI include federal Birds of Conservation Concern and Montana 

Species of Greatest Conservation Need. Appendix D lists the vertebrate species of special interest, 

summarizes their habitat requirements, and indicates if they have been observed on or within 

1 mile of the SCM permit area during long-term annual monitoring conducted for the SCM. The 

2008 (most current available) list of Birds of Conservation Concern for BCR 17 contains 28 species. 

Several of the species in BCR 17 have been documented at least once within the SCM wildlife 

monitoring area over time, though nearly half of those observations occurred with varying degrees 

of infrequency. The most abundant species recorded over time consisted of common raptors and 

passerine species known to nest in the survey area. Twenty-three Montana Species of Greatest 

Conservation Need have been documented in or within 1 mile of the SCM permit area, from 

1994 through 2015. Most of these species would be temporarily displaced but current reclamation 

practices in-place at the SCM would promote the return of these species once reclamation has 

been completed. The direct and indirect effects related to the Proposed Action on species of 

special interest would be moderate but extended to 2031.

4.10.4.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. 

These acres would not be disturbed at this time under the No Action Alternative. Indirect impacts 

to T&E species or SOSI have resulted from current mining activity. Under this alternative, impacts 

to T&E species and other species of special interest in the area would remain as described in 

section 4.10.4.1, but the affected area would be reduced by 728.4 acres and the duration of the 

effects would be shortened by 4 years.

4.10.4.2 Cumulative Effects

The cumulative effects to T&E species and SOSI would be similar to the direct and indirect impacts, 

discussed above.

4.10.4.3 Mitigation Measures

No mitigation measures specific to T&E species and SOSI would be necessary. General reclamation 

practices for establishing or enhancing post‐mine wildlife habitat at the SCM described in the 

Reclamation Plan (Section 17.24.313) of SMP C1979012 are in place. SCC has also implemented a 

mitigation plan specific to the potential disturbance of an existing prairie falcon eyrie.

4.11 Land Use and Recreation

4.11.1 Direct and Indirect Effects

4.11.1.1 Proposed Action

Additional discussions regarding land use and recreation can be found in sections 3.11 and 4.1.10 

of the 2010 LBM EA. Surface ownership in the area includes BLM and private lands and the 

proposed coal removal area is managed by the BLM and SCC. The major adverse ownership and 

land use consequences of mining the TR1 Tract would be reduction of livestock grazing, loss of 
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Spring Creek Mine TR1 EA 4-37

wildlife habitat, and curtailment of other mineral development on about 728.4 additional acres 

during active mining. Wildlife (particularly big game) use would be displaced while the tract is being 

mined and reclaimed. Livestock grazing has already been prohibited due to the tract being inside 

the permit boundary and adjacent to active mine areas. Hunting on the tract is currently not 

allowed within the mine permit boundary and would continue to be disallowed during mining and 

reclamation. Following reclamation, the land would be suitable for grazing and wildlife uses, which 

are the historic land uses. The direct and indirect effects related to the ownership and use of the 

land would be moderate and long term related to the length of time needed to obtain bond 

release, which would open up the land for post-mining land use.

4.11.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. 

These acres would not be disturbed at this time under the No Action Alternative. Indirect impacts 

to ownership and use of the land have resulted from current mining activity. Under this alternative, 

ownership and use of the land in the area would remain as described in section 4.11.1.1, but the 

duration of the effects would be shortened by 4 years.

4.11.2 Cumulative Effects

The cumulative effects on land use and recreation would be similar to the direct and indirect 

impacts discussed above and to the cumulative effects discussed in Section 4.1.10 of the 2010 LBM 

EA.

4.11.3 Mitigation Measures

No mitigation measures specific to land use and recreation would be necessary.

4.12 Cultural Resources

4.12.1 Direct and Indirect Effects

4.12.1.1 Proposed Action

Additional discussions regarding cultural resources can be found in sections 3.12 and 4.1.11 of the 

2010 LBM EA. The TR1 Tract has been subjected to Class III cultural resource inventories. One

site within the TR1 Tract (24BH3392) is classified as an NRHP eligible site that would require 

mitigation prior to disturbance. Data recovery plans are in place that are designed to mitigate the 

loss of archaeological resources in the mine operations area by expanding archaeological 

knowledge about this region. The data recovery plans are in compliance with SCC’s Memorandum 

of Agreement for cultural resources, which contains provisions for incidental cultural discoveries 

(MDEQ 2001). A mitigation plan for site 24BH3392 has been developed and approved by SHPO

(BLM 2010b) and site testing will be completed in 2020. The direct and indirect effects on cultural 

resource from the Proposed Action would be negligible but long term.

4.12.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. 

These acres would not be disturbed at this time under the No Action Alternative. While site 
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4-38 Spring Creek Mine TR1 EA

24BH3392 would not be disturbed, disturbance to minor cultural resources sites would continue 

due to mine related activity authorized under the currently approved state mine permit and federal 

mining plan. The direct and indirect effects on cultural resource from the No Action Alternative 

would be negligible but long term.

4.12.2 Cumulative Effects

The individual assessment of cultural resource sites evaluated by the SCM suggests that through 

avoidance of sensitive site types and mitigation through data recovery for all unavoidable 

disturbance to NRHP eligible sites, the cumulative effects to cultural resources have been minor. 

The cumulative effects on cultural resource would be negligible but long term.

4.12.3 Mitigation Measures

Mitigation would be required for the loss of the one NRHP eligible site. SCC’s cultural resources 

Memorandum of Agreement is in place to guide mitigation of incidental cultural discoveries that 

might be encountered during mining.

4.12.4 Unanticipated Discoveries 

If a previously unidentified cultural resource is discovered in the TR1 Tract, SCC would take 

measures to protect the find locality and provide written notice to the MDEQ and the OSMRE 

within 48 hours of the discovery. A Montana-permitted archaeologist meeting the Secretary of 

the Interior’s Professional Qualification Standards would, as soon as possible, evaluate the 

discovery, make a recommendation as to the NRHP eligibility of the resource, and provide written 

notice to the MDEQ and the OSMRE within 48 hours. The MDEQ and OSMRE would then consult 

with the Tribal Historic Preservation Office (THPO), SHPO, and the BLM (for federally managed 

sites) on the NRHP eligibility determination(s) and develop appropriate measures necessary to 

mitigate any adverse effects through the development of a treatment plan. 

Should the discovery involve a burial or a resource thought to have potential religious and cultural 

significance, the tribe(s) with an interest would be notified and consulted as appropriate. When 

agreement is reached among all of the involved parties, the appropriate mitigation, if necessary, 

would be implemented. The tribes, OSMRE, MDEQ, SHPO, and the surface landowner must agree 

to any proposed treatment measures.

4.13 Visual Resources

4.13.1 Direct and Indirect Effects 

4.13.1.1 Proposed Action

Additional discussions regarding visual resources can be found in sections 3.13 and 4.1.12 of the 

2010 LBM EA. No visual resources have been identified on or near the tract that are unique, as 

compared to the surrounding area. The mining operations would affect landscapes classified as 

Visual Resource Management (VRM) Class III by BLM. The objective of this class is to partially 

retain the existing character of the landscape. Reclaimed terrain would be almost indistinguishable 

from the surrounding undisturbed terrain. Slopes might appear smoother (less intricately 

dissected) than the surrounding undisturbed terrain, and sagebrush and trees would not be as 

abundant for several years; however, within a few years after reclamation, the mined land would 

not be distinguishable from the surrounding undisturbed terrain except by someone very familiar 

with landforms and vegetation. The direct and indirect effects related to the visual resources 

would be moderate but extended to 2031.
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-39

4.13.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. 

These acres would not be disturbed at this time under the No Action Alternative. Indirect impacts 

to visual resources have resulted from current mining activity. Under this alternative, visual 

resources in the area would remain as described in section 4.13.1.1, but the duration of the 

effects would be shortened by 4 years.

4.13.2 Cumulative Effects

The principal visual impact in this area is from the visibility of mine pits and facility areas associated 

with the SCM and the Decker Mine. People most likely to see these mining facilities would be local 

residents, those passing through the area, those visiting it on mine related business, or

recreationists using the Tongue River Reservoir. Pit and mine support facilities are generally not 

visible from more than a few miles away, but coal loading facilities and draglines can be seen from 

farther away. Due to the distance between mining operations, cumulative overlap of mining-related 

visual impacts is not likely. One public road (FAS 314), a railroad, and a power line also affect visual 

classification of the proposed tract. After mining, the reclaimed slopes might appear somewhat 

smoother than pre-mining slopes and there would be fewer gullies, bluffs, and rock outcrops than 

at present. Even so, the landscape of the reclaimed mine would look very much like undisturbed 

landscape in the area and, in this area, the reclaimed mine areas would be separated by areas 

where the topography is not disturbed. The cumulative effects related to the visual resources 

would be moderate but extended to 2031.

4.13.3 Mitigation Measures

No mitigation measures specific to visual resources would be necessary.

4.14 Noise

4.14.1 Direct and Indirect Effects 

4.14.1.1 Proposed Action

Additional discussions regarding noise can be found in sections 3.14 and 4.1.13 of the 2010 LBM 

EA. Surface activities associated with the Proposed Action, including noise from equipment, 

mining activity, and blasting, would continue to generate noise for an additional 4 years in a

manner comparable to the existing condition.

CPE has developed internal criteria on off-site noise acceptable for the protection of the local 

community and has established a 65 Adjusted decibels (dabs) threshold for noise. Modeling 

conducted for SCC indicates that this threshold would be exceeded at points less than 4,800 feet

(0.91 mile) from the disturbance.

The nearest residence is approximately 2.8 miles from the TR1 Tract disturbance and FAS 314 is 

approximately 1.4 miles from the disturbance. The nearest recreational opportunity is at the 

Tongue River Reservoir, approximately 2.6 miles from the tract disturbance. Direct and indirect 

effects related to noise would be significant in the immediate vicinity of the tract disturbance from 

equipment, mining activity, and blasting but these effects would moderate rapidly as the distance

from disturbance increased. Direct and Indirect effects to residents, people using FAS 314, and 
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4-40 Spring Creek Mine TR1 EA

recreationalists using the Tongue River Reservoir would be minor due to the distance from mine 

related activity associated with the tract.

Because OSMRE does not regulate rail traffic (see section 3.1), for associated environmental 

impacts, this EA relies upon STB regulations, which only require analysis of noise where rail traffic 

increases at least 100 percent (i.e., doubles) or increases by at least 8 trains per day on any segment 

(49 C.F.R. Part 1105.7e(6)). As discussed in section 4.15.1.1, the Proposed Action could increase 

rail traffic by 3 percent and increase the number of trains per day by less than 1train. Therefore, 

a noise analysis associated with rail traffic is not required. Local impacts from noise and vibration 

would be increased by the addition of less than one additional train per day over 2018 traffic.

Therefore, the impacts from noise and vibration from the Proposed Action would be minor.

4.14.1.2 No Action Alternative

While the entire disturbance area associated with the Proposed Action has been approved for 

disturbance under the recently approved TR1 MR for SMP C1979012, approximately 728.4 acres 

of surface disturbance are anticipated related to mining the federal coal within the TR1 Tract. 

These acres would not be disturbed at this time under the No Action Alternative. Noise from 

current mining activities have negligible impact people using FAS 314, and recreationalists using 

the Tongue River Reservoir. Under this alternative, noise impacts in the area would remain as 

described in section 4.14.1.1, but for a shorter duration.

4.14.2 Cumulative Effects

Existing land uses within the Spring Creek area (e.g., mining, livestock grazing, transportation, and 

recreation) contribute to noise levels, but wind is generally the primary noise source. Mining in 

the area increases the number of noise-producing facilities within the area and may augment the 

level of impacts to other resources (e.g., increased exposure of wildlife to noise impact, increased 

noise impacts to local residents and recreational users). Mining-related noise is generally masked 

by the wind at short distances, so cumulative overlap of noise impacts between the SCM and the 

Decker Mine is not likely.

Recreational users, local residents and grazing lessees using lands surrounding active mining areas 

do hear mining-related noise, but this has not been reported to cause a substantial impact. Wildlife 

in the immediate vicinity of mining may be adversely affected by noise; however, observations at 

the SCM indicate that wildlife generally adapt to noise conditions associated with active coal 

mining. The cumulative effects related to noise as discerned by the public would be moderate but 

short term (4 years).

4.14.3 Mitigation Measures

No mitigation measures specific to noise impacts would be necessary.

4.15 Transportation Facilities

4.15.1 Direct and Indirect Effects 

4.15.1.1 Proposed Action

Additional discussions regarding transportation facilities can be found in section 3.15 of this EA 

and in Sections 3.15 and 4.1.14 of the 2010 LBM EA. Major local roads and railroads are presented 

on map 1-1 and U.S. railroad routes used by BNSF to transport SCM coal to various destinations 

are shown on map 1-3. 
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-41

Vehicle Transportation

No new public roads would be required to support the Proposed Action and mining the 

proposed tract would not increase the current level of impact on FAS 314. As discussed in section 

3.15, the highest average hourly vehicle count at a site just north of the Montana/Wyoming border 

over the last 5 years (36 vehicles in 2015) was well under the 2018 design hourly volume for the 

road (76). Therefore, mine-related traffic would continue to have minor impacts to public roads,

but would extend the impacts by 4 years, until 2031.

Rail Transportation

Section 3.15 indicated that the annual 2018 rail traffic related to coal transport was 

approximately 2,195,150 miles (based on the shipment of 13.77 Mt of coal to 7 destinations). The 

2014-2018 average annual rail traffic related to coal transport was approximately 2,266,376 miles

to transport 14.21 Mt of coal. The annual rail traffic evaluated for the Proposed Action is difficult 

to calculate since the amount and destination of coal shipped is related to coal contracts negotiated 

by the mine with potential clients, which can vary from year to year, and the specific client 

information (specific destinations and tons shipped) is not publicly available. However, as 

determined from publicly available information, rail traffic related to SCM coal shipments has 

remained relatively consistent for the last 5 years, with approximately 91 percent of coal shipments 

going to the same 6 destinations. Therefore, this EA assumes that the destinations and the 

destination distances for SCM coal would remain relatively consistent through 2031. The Proposed 

Action is being evaluated at a coal production rate of 14.20 Mtpy so impacts from rail 

transportation related to the Proposed Action will be evaluated using 2,266,324 miles (based on 

the percent change of projected annual shipments compared to the 2014-2018 average number of 

shipments). The 2020-2031 average annual number of trips (loaded and empty) for trains shipping 

SCM would decrease from approximately 1,822 to approximately 1,820. It is reasonable to assume 

that the current total U.S. miles of freight shipped would remain relatively constant through 2031

based on 2014 through 2018 statistics from the USDOT. The average annual haul distance 

between 2014 and 2018 for freight trains throughout the U.S. was slightly less than 481,475,400 

miles (USDOT 2019).

The potential for train derailments would continue for an additional 4 years. Even with fluctuations in 

the coal market, the railroad would maximize train traffic (Stephens 2018) and the overall number of 

trains would remain constant, independent of the number of coal trains.

The potential for emissions of dust from the large volumes of coal transported to large generating 

stations can be an environmental concern (Ramboll Environ 2016). Coal dust and fines blowing or 

sifting from moving, loaded rail cars has been linked to railroad track stability problems resulting 

in train derailments and to rangeland fires caused by spontaneous combustion of accumulated coal 

dust (BLM 2009). In response to suits brought on by environmental groups alleging that coal spilled 

from trains pollutes waterways, BNSF Railway has agreed to study the use of physical covers for 

coal trains to reduce the effects of blowing coal particles (Seattle Times 2016). BNSF has cited 

studies and experience to demonstrate that shippers can take steps in the loading of coal cars 

using existing, cost-effective technology that will substantially reduce coal dusting events. BNSF 

has a Coal Loading Rule, in effect since October 2011, specifically requiring all shippers loading 

coal at any Montana or Wyoming mine to take measures to load cars in such a way that ensures 

coal dust losses in transit are reduced by at least 85 percent compared to cars where no remedial 

measures have been taken (BNSF 2016).
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4-42 Spring Creek Mine TR1 EA

This EA acknowledges that the Proposed Action would result in increased indirect impacts from 

coal-train transport (public health, collisions with wildlife, dust, noise, and vibration). However, 

mine-related coal shipments would have minor local and regional impacts (the potential for a 3

percent increase in rail traffic related to coal from the SCM, which translates to 50 additional 

trains per year and 0.14 train per day). The impacts related to public health, collisions with wildlife, 

dust, noise, and vibration would be minor but extended by 4 years, until 2031.

4.15.1.2 No Action Alternative

Under this alternative, transportation impacts in the area would remain as described in 

section 4.15.1.1, but the duration of the effects would be shortened by 4 years.

4.15.2 Cumulative Effects

Cumulative impacts to transportation are related to coal production. If coal production is 

extended, cumulative effects to transportation would be extended. Highway traffic accidents and 

delays at grade crossings could result from train traffic to power plants and ports. The local, 

regional, and national transportation facilities used to ship coal from the SCM are already in place 

and current coal production levels are not expected to change with the Proposed Action. 

However, the Proposed Action would extend the duration of mining by approximately 4 years at 

the SCM and thus the indirect impacts to transportation (the extension of the duration of traffic 

from mine employees, possible delays from train traffic, possible delays from mine equipment 

crossing FAS 314, and impacts from coal shipments using trains [public health, collisions with 

wildlife, dust, noise, and vibration] and overseas vessels) would be extended. The annual rail traffic 

generated by the Proposed Action represents an estimated 0.45 percent of the of the total U.S. 

rail freight traffic (based on 2018 U.S. rail transportation numbers and the shipment of 14.2 Mt of 

coal) so the cumulative effects related to transportation would be minor but extended to 2031.

4.15.3 Mitigation Measures

No mitigation measures specific to transportation would be necessary.

4.16 Hazardous and Solid Waste

4.16.1 Direct and Indirect Effects 

4.16.1.1 Proposed Action

Additional discussions regarding hazardous and solid wastes can be found in sections 3.16 and 

4.1.15 of the 2010 LBM EA. Wastes classified as non-hazardous, hazardous, and universal are 

generated during mining operations at the SCM. The SCM closed the onsite solid waste landfill in 

2015. As a result, non-hazardous solid waste is shipped to the municipal landfill in Hardin, Montana. 

The only wastes disposed of onsite are wastes such as abandoned mining machinery, non-greasy 

wood, used tires, concrete, and other items permitted under the mine’s existing MDEQ permit to 

mine. The SCM generates some non-hazardous liquids including used oil, used grease, used 

antifreeze, and spent non-hazardous solvents. The used oil, paper, cardboard, plastic bottles, 

aluminum cans, and scrap steel are shipped off-site for recycling. The SCM also generates some 

hazardous wastes including flammable liquids and other combustible materials determined to be 

hazardous by the EPA under the Resource Conservation and Recovery Act. Hazardous waste and 

non-hazardous used grease and used antifreeze are incinerated for energy recovery at an off-site 

EPA-permitted facility. The SCM also generates universal wastes including used batteries, 

electronic waste, and used light bulbs that are shipped off-site for recycling. No solid waste is 
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Spring Creek Mine TR1 EA 4-43

deposited within 8 feet of any coal outcrop or coal storage area, or at refuse embankments or 

impoundment sites (SCC 2019). No direct or indirect effects from hazardous and solid waste are 

anticipated as a result of the Proposed Action. 

4.16.1.2 No Action Alternative

Under this alternative, impacts from hazardous and solid wastes in the area would remain as 

described in section 4.16.1.1, but the duration of the effects would be shortened by 4 years.

4.16.2 Cumulative Effects

As indicated in Section 4.1.15 of the 2010 LBM EA, no additional cumulative hazardous or solid 

waste impacts are expected. 

4.16.3 Mitigation Measures

No mitigation measures specific to hazardous and solid wastes would be necessary.

4.17 Socioeconomics

4.17.1 Direct and Indirect Effects 

4.17.1.1 Proposed Action

Additional discussions regarding socioeconomic impacts can be found in sections 3.17 and 4.1.16 

of the 2010 LBM EA. Under the Proposed Action, additional Montana revenues (royalties, 

severance tax, gross proceeds tax, and resource indemnity trust tax) could total approximately 

$134.4 million and additional federal revenues (royalties, black lung tax, and federal recreation tax) 

could total $61.2 million over the life of the mine. The primary difference between state and 

federal revenues is related to the fact that severance taxes are only paid to the state of Montana. 

The positive direct and indirect effects described above (additional revenues) would be moderate 

and would be extended by approximately 4 years, to 2031.

No new employees would be added under the Proposed Action and there would be no direct or 

indirect effects on the local work force. Mine employees would travel north from Sheridan and 

would not have to travel across either the Crow or Northern Cheyenne Reservations. SCC 

proposes to use emergency services from Sheridan, if necessary. The Proposed Action would not 

require employees to move into the area near the project. Therefore, no adverse human health 

or environmental effects would be expected to fall disproportionately on minority or low income 

populations as a result of the Proposed Action. No direct or indirect effects to environmental 

justice are anticipated as a result of the Proposed Action.

Mining in the TR1 Tract would not directly create new jobs and therefore, the availability of 

housing units would not be impacted. No additional employees are anticipated as a result of the 

tract being mined, although the Proposed Action would extend the duration of employment for 

current employees and extend the substantial economic benefits related to mining the federal coal. 

The positive direct and indirect effects described above (continued employment) would be 

moderate and would be extended by approximately 4 years, to 2031.

4.17.1.2 No Action Alternative

In terms of coal conservation; the No Action Alternative would mean that mineable federal coal 

within MTM-069782 would not be recovered. Approximately 53.6 Mt of federal coal would not 

be recovered along margins of existing leases. Montana revenues would be reduced by 
Chapter 4 – Environmental Consequences/Cumulative Effects

4-44 Spring Creek Mine TR1 EA

approximately $134.4 million and federal revenues of approximately $61.2 million related to this 

coal would not be realized over the LOM under No Action Alternative. The selection of the No 

Action Alternative would likely not result in direct job losses, but any revenue, state program 

funding, abandoned mine land fees, and black lung fees that might otherwise be generated by 

extending the LOM by 4 years would not be collected. In addition, the duration of employment 

for current employees would be reduced by 4 years. The No Action Alternative would result in 

moderate direct and indirect socioeconomic effects.

4.17.2 Cumulative Effects

Cumulative impacts related to the Proposed Action are not significantly different than those 

described in section 4.17.1.1, above. Montana and Big Horn County have been using the 

revenues for a variety of programs (Montana Department of Revenue 2018). Montana would 

collect additional revenues of approximately $134.4 million and federal revenues would increase 

by approximately $61.2 million related to this coal over the LOM, with a portion of the state

revenues distributed to Big Horn County. Cumulative impacts would extend the duration of 

employment for current employees and extend the substantial economic benefits related to mining 

the federal coal. The positive cumulative effects on socioeconomics are expected to be moderate 

but short term (4 years). 

4.17.3 Mitigation Measures

No mitigation measures specific to socioeconomic impacts are needed.

4.18 Short Term Uses and Long-term Productivity

This section relates to the balance or trade-off between short-term uses and long-term productivity 

for each resource in relation to the Proposed Action. The discussions contained throughout this 

environmental consequences chapter, in the existing SCM federal mining plan, and in the 2010 LBM 

EA adequate analyses and relationships of short-term uses (such as mining coal) and long-term 

productivity (such as generating electricity for homes, schools, and industry).

4.19 Unavoidable Adverse Effects

Unavoidable adverse impacts are the effects on natural and human resources that would remain 

after mitigation measures have been applied. For the Proposed Action, details regarding these

impacts are presented in the preceding resource sections and the 2010 LBM EA. Unavoidable

adverse effects are summarized in table 4-6.
Chapter 4 – Environmental Consequences/Cumulative Effects

Spring Creek Mine TR1 EA 4-45

Table 4-6. Unavoidable Adverse Effects of the Proposed Action

Resource Unavoidable Adverse Effect

Topography and

Physiography

Topographic effects of mining (surface configurations) are unavoidable because mining 

activities such as blasting, excavating, loading and hauling of overburden and coal are 

required to recover coal in an economical manner.

Geology, Mineral

Resources and

Paleontology

Geology (stratigraphic units), mineral resources and buried paleontological resources 

may be permanently impacted by mining activities. Such impacts are unavoidable as the 

resources cannot be avoided by mining activities.

Air Quality Emissions and associated impacts are unavoidable but are not expected to degrade 

ambient air quality in the area. Mined coal is primarily used for combustion; therefore,

any associated GHG emissions are unavoidable if the Proposed Action is implemented.

Water Resources Impacts to water resources resulting from coal extraction are unavoidable. However,

these impacts would be mitigated through replacement of groundwater or surface water 

supplies for domestic, agricultural, industrial, or any other legitimate use if such a supply 

is diminished, interrupted, or contaminated, to the extent of precluding use of the water, 

as a result of mining.

Soil Soil in disturbance area would exhibit more homogenous textures and may have coarser

fragments near the surface following mining. Some soil loss may occur as a result of

erosion, prior to stabilization.

Vegetation Vegetation would be eliminated beginning with the initial disturbance and continuing until

reclamation is complete, which would extend to the end of the mining term for many

facilities. Noxious weeds may be introduced as a result of mining activity, potentially

affecting vegetation communities and requiring implementation of control measures in 

the long term.

Wildlife Wildlife would be temporarily affected by mine activities, which would alter habitat 

conditions, particularly in the vicinity of surface disturbance. These impacts would be

short term and habitats would be reclaimed following mining.

Cultural Resources Although searches would be conducted, undiscovered cultural resources could be 

impacted by subsidence and surface disturbing activities. All discovered sites would be

mitigated as required by Section 106 of the NHPA. One site within the disturbance area 

for the TR1 Tract (24BH3392) is classified as an NRHP eligible site, which require 

mitigation prior to disturbance. Data recovery plans are in place that are designed to 

mitigate the loss of archaeological resources in the mine operations area by expanding 

archaeological knowledge about this region. The data recovery plans are in compliance 

with SCC’s Memorandum of Agreement for cultural resources, which contains 

provisions for incidental cultural discoveries (MDEQ 2001). A mitigation plan for site 

24BH3392 has been developed with consultation from MDEQ and SHPO and the site 

will be tested in 2020.

Visual Resources Mining activity and associated disturbances and facilities would unavoidably alter the

landscape during the mining term, affecting the aesthetic qualities. Some features could

be visible from public access points, including Montana FAS 314. The effects would be

negligible following reclamation.

Noise Noise would result from mining activities and transportation similar to the existing 

condition, which is unavoidable. 

Transportation

Facilities

Route FAS 314 would continue to experience mine related traffic. BNSF rail lines would 

also continue to experience traffic. The effects would occur during the mining term.

Hazardous and

Solid Waste

Coal mining and associated coal processing would yield unavoidable coal waste.

Chapter 5 – Consultation and Coordination

Spring Creek Mine TR1 EA 5-1

5.0 Consultation and Coordination

5.1 Public Comment Process 

OSMRE developed a project specific website that provided legal notices, outreach notice letters, 

mailing address, and an email address for comments to be sent. The website was activated on 

February 11, 2016 and is available at

http://www.wrcc.osmre.gov/initiatives/SpringcreekMineTR1.shtm.

Public outreach letters describing the EA and soliciting scoping comments were mailed on 

February 11, 2016 to a total of 92 recipients, including city governments, adjacent landowners, 

and other interested parties. The legal notices and letters invited the public to comment on issues 

of concern related to the EA. OSMRE also sent letters of notification to 26 tribes/tribal 

representatives. These tribal notification letters were mailed on February 11, 2016.

OSMRE received written and e-mailed comments from 4,214 entities. A form letter in favor of 

the SCM accounted for 4,213 comments. Comment letters received during the public review 

period for this EA will be considered during the ASLM approval process. Appendix A presents 

a summary of the substantive EA scoping comments.

OSMRE released a public notice of the availability of the EA in the Hardin Times and the Sheridan 

Press on February 13, 2020. Written comments were solicited until March 13, 2020.

5.2 Preparers and Contributors

OSMRE personnel that contributed to the development of this EA are listed in table 5-1 and 

third party contractors who contributed to the development of this EA are identified in

table 5-2.

Table 5-1. OSMRE Personnel

Name Organization Project Responsibility

Logan Sholar OSMRE Project Lead/Project Coordination

Gretchen Pinkham OSMRE Air Quality

Roberta Martinez Hernandez OSMRE Hydrology

Ed Vasquez OSMRE Ecology

Stephanie Hamlett OSMRE Environmental Protection Specialist

Jeremy Iliff OSMRE Cultural/Historical/Paleontological

Table 5-2. Third Party Contractor Personnel

Name Organization Project Responsibility Education/Experience

John Berry WWC Engineering Project Manager, Primary Author B.S. Wildlife Management

Beth Kelly WWC Engineering QAQC B.S. Chemical Engineering

Mal McGill WWC Engineering AutoCAD A.S. Engineering

5.3 Distribution of the EA

This EA will be distributed to individuals who specifically request a copy of the document. It will 

also be made available electronically on the OSMRE website at 

http://www.wrcc.osmre.gov/initiatives/SpringcreekMineTR1.shtm.

Chapter 6 – References

Spring Creek Mine TR1 EA 6-1

6.0 References

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Billings Gazette, 2014, Kentucky-based Ramaco plans new coal mine near Sheridan. Article 

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Brander, M. 2012. Greenhouse Gases, CO2, CO2e, and Carbon: What Do All These Terms

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Coal Lease Sale in the Powder River Region. USDI, BLM. Available on the Internet as of 

September 2019 at: https://archive.org/details/draftenvironment3623unit.

Bureau of Land Management (BLM), 2003, Final Statewide Oil and Gas Environmental Impact 

Statement and Proposed Amendment of the Powder River and Billings Resource 

Management Plan. Montana State Office, Billings, Montana. Available on the Internet as of 

September 2019 at: 

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Bureau of Land Management (BLM), 2008, BLM Manual 6840 – Special Status Species 

Management. Available on the Internet as of September 2019 at: 

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Bureau of Land Management (BLM), 2009, Environmental Impact Statement for the South Gillette 

Area Coal Lease Applications WYW172585, WYW173360, WYW172657, WYW161248. 

Document not yet available on BLM E-Planning Website. Electronic copy available on 

request from OSMRE.

Bureau of Land Management (BLM), 2010a, Finding of No Significant Impact and Decision Record 

for Environmental Assessment for Spring Creek Coal Lease Modification MTM-069782 

and Amendment to Land Use Lease MTM-74913 EA# MT-DOI-BLM-MT-020-2010-29. 

Available on the Internet as of November 2019 at: 

https://leg.mt.gov/content/publications/mepa/2012/deq0703_2012004.pdf.
Chapter 6 – References

6-2 Spring Creek Mine TR1 EA

Bureau of Land Management (BLM), 2010b, Montana State Historic Preservation Office (SHPO) 

Consultation letter. Electronic copy only. Available on request from OSMRE.

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2011 Final Report. Available on the Internet as of November 2019 at: 

https://landscape.blm.gov/geoportal/rest/find/document?searchText=%22BLM%20REA%20

NWP%202011%22&start=1&max=10&f=searchpage&contentType=document.

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Final Environmental Impact Statement. Available on the Internet as of September 2019 at: 

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eId=79235.

Bureau of Land Management (BLM), 2018, Regulatory Impact Analysis for the Proposed Rule to 

Rescind or Revise Certain Requirements of the 2016 Waste Prevention Rule. Available on 

the Internet as of April 2020 at:

https://www.regulations.gov/contentStreamer?documentId=BLM-2018-0001-

0002&contentType=pdf.

Conant, R.T., D. Kluck, M. Anderson, A. Badger, B.M. Boustead, J. Derner, L. Farris, M. Hayes, B. 

Livneh, S. McNeeley, D. Peck, M. Shulski, and V. Small. 2018. Northern Great Plains. In 

Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, 

Vol. II, edited by D.R. Reidmiller, C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, 

T.K. Maycock, and B.C. Stewart, pp. 941–986, doi: 10.7930/ NCA4.2018.CH22. Available 

on the Internet as of September 2019 at: https://nca2018.globalchange.gov/chapter/22/.

Climate Change Advisory Committee (CCAC), 2007, Montana Climate Change Action Plan Final 

Report of the Governor’s Climate Change Advisory Committee, November 2017. Available 

on the Internet as of September 2019 at: 

https://deq.mt.gov/Portals/112/Energy/ClimateChange/Documents/FinalReportChapters.pdf.

Cloud Peak Energy (CPE), 2015, Cloud Peak Energy 2015 Annual Corporate Report. Available on 

the Internet as of September 2019 at: http://investor.cloudpeakenergy.com/annualreports.

Cloud Peak Energy (CPE)/Redhorse Corporation (Redhorse), 2014, Dispersion Modeling 

Protocol for Expansion of the Spring Creek Mine. Submitted to Montana Department of 

Environmental Quality, Air Resources Management Bureau. April. Electronic copy only. 

Available on request from OSMRE.

Crawford, John A., Rich A. Olson, Neil E. West, Jeffrey C. Mosley, Michael A. Schroeder, Tom D. 

Whitson, Richard F. Miller, Michael A. Gregg, And Chad S. Boyd, 2004, Synthesis Paper 

Ecology and management of sage-grouse and sage-grouse habitat. Available on the Internet 

as of September 2019 at: http://wdfw.wa.gov/publications/01301/wdfw01301.pdf.

Department of Interior (DOI), 2004, Department of the Interior Departmental Manual Part 516. 

Available on the Internet as of September 2019 at: https://www.doi.gov/elips/browse.
Chapter 6 – References

Spring Creek Mine TR1 EA 6-3

Fenneman, Nevin M., 1931, Physiography of Western United States, McGraw-Hill, pages 54-60.

Electronic copy only. Available on request from OSMRE.

Great Plains Wildlife Consulting, Inc., 2017, Spring Creek Mine 2016 Wildlife Monitoring Report. 

Prepared for: Cloud Peak Energy Resources LLC. Electronic copy only. Available on 

request from OSMRE.

Great Plains Wildlife Consulting, Inc., 2019, Spring Creek Mine 2018 Wildlife Monitoring Report. 

Prepared for: Cloud Peak Energy Resources LLC. Electronic copy only. Available on 

request from OSMRE.

Government Publishing Office (GPO), 1982, 43 Code of Federal Regulations (C.F.R.) §3425.1. 

Available on the Internet as of September 2019 at: https://www.gpo.gov/fdsys/pkg/C.F.R.-

2004-title43-vol2/pdf/C.F.R.-2004-title43-vol2-sec3425-1-5.pdf.

Hayhoe, K., D.J. Wuebbles, D.R. Easterling, D.W. Fahey, S. Doherty, J. Kossin, W. Sweet, R.

Vose, and M. Wehner, 2018, Our Changing Climate. In Impacts, Risks, and Adaptation in 

the United States: Fourth National Climate Assessment, Vol. II, edited by D.R. Reidmiller, 

C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart, 

pp. 72–144, doi: 10.7930/NCA4.2018.CH2. Washington, D.C.: U.S. Global Change 

Research Program. Available on the Internet as of April 2020 at: 

https://nca2018.globalchange.gov/chapter/2/. 

Hope, Chris, 2013, “Critical issues for the calculation of the social cost of CO2: why the 

estimates from PAGE09 are higher than those from PAGE2002.” Climatic Change, 117: 

531-543. Available on the Internet as of April 2020 at:

https://www.researchgate.net/publication/257548138_Critical_issues_for_the_calculation

_of_the_social_cost_of_CO2_Why_the_estimates_from_PAGE09_are_higher_than_tho

se_from_PAGE2002/link/58aece3fa6fdcc6f03f2662f/download.

Interagency Monitoring of Protected Environments (IMPROVE), 2019, Data Acquired from 

Interagency Monitoring of Protected Visual Environments. Available on the Internet as of 

September 2019 at: http://vista.cira.colostate.edu/improve/.

Interagency Working Group on the Social Cost of Carbon, United States Government, 2010,

Technical Support Document: Social Cost of Carbon for Regulatory Impact Analysis – Under 

Executive Order 12866. Available on the Internet as of April 2020 at:

https://www.epa.gov/sites/production/files/2016-12/documents/scc_tsd_2010.pdf. 

Intergovernmental Panel on Climate Change (IPCC), 2014, Climate Change 2014 Synthesis 

Report. Available on the Internet as of April 2020 at: 

https://www.ipcc.ch/site/assets/uploads/2018/02/SYR_AR5_FINAL_full.pdf.

Inter-Mountain Lab (IML), 2018, SCM 2018 4

th Quarter and Annual Report, Spring Creek Coal 

LLC Ambient Air Monitoring Network. Electronic copy only. Available on request from 

OSMRE.

Marine Traffic, 2019, Voyage Planner - Distance calculator. Available on the Internet as of 

September 2019 at: http://www.marinetraffic.com/.
Chapter 6 – References

6-4 Spring Creek Mine TR1 EA

Merrill, M.D., Sleeter, B.M., Freeman, P.A., Liu, J., Warwick, P.D., and Reed, B.C., 2018, federal 

lands greenhouse emissions and sequestration in the United States—Estimates for 2005–

14: U.S. Geological Survey Scientific Investigations Report 2018–5131, 31 p., Available on 

the Internet as of November 2019 at: https://doi.org/10.3133/sir20185131.

Montana Board of Oil and Conservation (MBOGC), 2019, CX Field Drilling Well Information. 

MBOGC's Online Oil and Gas Information System – Big Horn County. Available on the 

Internet as of September 2019 at:

http://www.bogc.dnrc.mt.gov/WebApps/DataMiner/CBM/CBMWells.aspx.

Montana Coal Council, 2018, Montana Coal 2017 Brochure. Available on requests at: 

mtcoal@aol.com.

Montana Code Annotated (MCA), 2015, Montana Annotated Code 2015 – 82-4-203. Available on 

the Internet as of September 2019 at: http://leg.mt.gov/bills/mca/82/4/82-4-203.htm.

Montana Department of Natural Resources and Conservation (Montana DNRC), 2019, Water 

rights Query System. Available on the Internet as of September 2019 at:

http://wrqs.dnrc.mt.gov/default.aspx.

Montana Department of Environmental Quality (MDEQ), 2001, Spring Creek Coal; Proposed 

Carbone Amendment. August 10, 2001 letter from MDEQ to agencies regrading a 

Memorandum of Agreement to the Advisory Council On Historic Preservation for 

Cultural Resource Protection and Archeological Data Recovery at the Spring Creek Mine.

Electronic copy only. Available on request from OSMRE.

Montana Department of Environmental Quality (MDEQ)/Permitting and Compliance Division 

(PCD), 2014, Spring Creek Coal, LLC-Montana air quality permit #1120-12. Available on 

the Internet as of September 2019 at:

https://deq.mt.gov/Portals/112/Air/AirQuality/Documents/ARMpermits/1120-12.pdf.

Montana Department of Environmental Quality (MDEQ)/Water Quality Division (WQD), 2020, 

Spring Creek Mine Cumulative Hydrologic Impact Assessment Major Revision TR1.

Electronic copy only. Available on request from OSMRE.

Montana Department of Revenue, 2018, Montana Department of Revenue Biennial Report July 1, 

2016-June 30, 2018. Available on the Internet as of September 2019 at: 

https://mtrevenue.gov/wp-content/uploads/2019/01/2016-2018-Biennial-Report.pdf.

Montana Fish, Wildlife & Parks (MFWP), 2015, Montana's State Wildlife Action Plan 2015. 

Available on the Internet as of September 2019 at: 

http://fwp.mt.gov/fwpDoc.html?id=70168.

Montana Fish, Wildlife & Parks (MFWP), 2016, Montana Fish, Wildlife & Parks Crucial Areas 

Assessment. Available on the Internet as of September 2019 at: 

http://fwp.mt.gov/gis/maps/caps/.
Chapter 6 – References

Spring Creek Mine TR1 EA 6-5

Montana Fish, Wildlife & Parks (MFWP), 2019, Montana Greater Sage-grouse Population Report, 

September 3, 2019. Available on the Internet as of September 2019 at: 

https://leg.mt.gov/content/Committees/Interim/2019-2020/EQC/Meetings/Sept-2019/sagegrouse-2019.pdf.

Montana’s Greater Sage-grouse Habitat Conservation (MGRSG) Advisory Council, 2014, Greater 

Sage-Grouse Habitat Conservation Strategy. Available on the Internet as of September 

2019 at: http://governor.mt.gov/Portals/16/docs/GRSG%20strategy%2029Jan_final.pdf.

Montana Natural Heritage Program (MTNHP), 2019, Montana Natural Heritage – Animal SOC 

Report. Available on the Internet as of September 2019 at: 

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Montana Secretary of State, 2015, Montana Secretary of State 2015 Rule: 17.24.1116 Bonding: 

Criteria and Schedule for Release of Bond. Available on the Internet as of September 2019 

at: http://www.mtrules.org/gateway/ruleno.asp?RN=17.24.1116.

National Atmospheric Deposition Program (NADP), 2019, National Atmospheric Deposition 

Program-Annual Averages for NTN Site MT00. Wisconsin State Laboratory of Hygiene, 

University of Wisconsin-Madison, WI. Individual years available on the Internet as of 

September 2019 at: 

https://nadp.slh.wisc.edu/data/sites/siteDetails.aspx?net=NTN&id=MT00.

National Conference of State Legislatures (NCSL), 2019, State Renewable Portfolio Standards 

and Goals. Available on the Internet as of November 2019 at: 

http://www.ncsl.org/research/energy/renewable-portfolio-standards.aspx.

Nordhaus, W, 2014, “Estimates of the Social Cost of Carbon: Concepts and Results from the 

DICE-2013R Model and Alternative Approaches.” Journal of the Association of 

Environmental and Resource Economists, 1(1/2): 273-312. Available on the Internet as of 

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Office of the Governor, 2015, Executive Order Amending and Providing for Implementation of 

the Montana Sage Grouse Conservation Strategy. Available on the Internet as of 

September 2019 at: 

https://sagegrouse.mt.gov/documents/Program_Resources/EXECUTIVE%20ORDER_12_2

015_Sage_Grouse.pdf.

Office of Management and Budget, 2003, Circular A-4: Regulatory Analysis. Washington, DC. 

Available on the Internet as of June 2019 at: 

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Preparation of Mining Plan Decision Documents. Available on the Internet as of 

September 2019 at: http://www.osmre.gov/lrg/directives.shtm.
Chapter 6 – References

6-6 Spring Creek Mine TR1 EA

Office of Surface Mining Reclamation and Enforcement (OSMRE), 2015, Reclamation 

Performance Bonds Bonding Review. Available on the Internet as of September 2019 at: 

http://www.osmre.gov/resources/bonds/bondsoverview.shtm.

Office of Surface Mining Reclamation and Enforcement (OSMRE), 2016a, Spring Creek Mine, 

LBA1 Mining Plan Modification Environmental Assessment website. Available on the 

Internet as of September 2019 at: 

http://www.wrcc.osmre.gov/initiatives/SpringcreekMineLBA1.shtm.

Office of Surface Mining Reclamation and Enforcement (OSMRE), 2016b, Initiatives – Spring 

Creek Mine. Available on the Internet as of September 2019 at: 

https://www.wrcc.osmre.gov/initiatives/SpringcreekMineTR1.shtm.

Office of Surface Mining Reclamation and Enforcement (OSMRE), 2018, Annual Evaluation Report 

for the Regulatory Program Administered by the Department of Environmental Quality –

Coal and Opencut Mining Bureau of Montana. Available on the Internet as of September 

2019 at: https://www.odocs.osmre.gov/.

Office of Surface Mining Reclamation and Enforcement (OSMRE), 2019, REG-1 995-Handbook 

on Procedures for Implementing the NEPA; National Environmental Policy Act (NEPA) 

Handbook. Available on the Internet as of September 2019 at: 

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Pace, Thomas G., 2005, Examination of the Multiplier Used to Estimate PM2.5 Fugitive Dust 

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Atmospheric Environment 28(5): 1,049-1,054. Electronic copy only. Available on request 

from OSMRE.

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from OSMRE.

Rose, S.K., D. Turner, G. Blanford, J. Bistline, F. de la Chesnaye, and T. Wilson, 2014, 

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Chapter 6 – References

Spring Creek Mine TR1 EA 6-7

Seattle Times (2016), BNSF to Study Coal Covers Under Tentative Lawsuit Agreement. Available 

on the internet as of April 2020: http://www.seattletimes.com/seattlenews/environment/enviros-bnsf-railway-reach-agreement-in-coal-dust-lawsuit/.

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Spring Creek Coal Company (SCC), 2001, Spring Creek Mine 5-Year Permit Application, Permit 

C1979012, Approved by Montana Department of Environmental Quality. Electronic copy 

only. Available on request from OSMRE.

Spring Creek Coal Company (SCC), 2014, Spring Creek Mine SMP C1979012. Electronic copy 

only. Available on request from OSMRE.

Spring Creek Coal Company (SCC), 2018a, 2018 Air Monitoring Network, 4th Quarter & Annual 

Report. Electronic copy only. Available on request from OSMRE.

Spring Creek Coal Company (SCC), 2018b, 2018 Annual Hydrology Report, October 1, 2017 –

September 30, 2018. Electronic copy only. Available on request from OSMRE.

Spring Creek Coal Company (SCC), 2019, Information provided by the Spring Creek Mine Used in 

the Preparation of the EA. Electronic copy only. Available on request from OSMRE.

Thunder Basin Grasslands Prairie Ecosystem Association (TBGPEA), 2019, What We do. Available 

on the Internet as of September 2019 at: https://www.tbgpea.org/who-we-are/what-wedo.

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https://www.eia.gov/coal/annual/archive/05842017.pdf.
Chapter 6 – References

6-8 Spring Creek Mine TR1 EA

U.S. Energy Information Administration (USEIA), 2019, Coal Data Browser, Shipments from the 

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(Green Book)- Areas of the Country That Meet or Violate Air Quality Standards. 

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U.S. Environmental Protection Agency (EPA), 2018b, Overview of Greenhouse Gases. Available 

on the Internet as of April 2020 at: https://www.epa.gov/ghgemissions/overviewgreenhouse-gases.

U.S. Environmental Protection Agency (EPA), 2018c, Greenhouse Gas Emissions. Sources of 

Greenhouse Gas Emissions. Available on the Internet as of April 2020 at: 

https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emissions. 

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Values Report. Available on the Internet as of December 2019 at: 

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Emissions and Sinks, 1990-2017. Available on the Internet as of September 2019 at: 

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main-text.pdf.

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as of January 2020: https://www.epa.gov/acidrain/what-acid-rain.

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FLIGHT. Available on the Internet as of April 2020 at: 

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U.S. Environmental Protection Agency (EPA), 2019e, Particle Pollution and Your Patients' Health. 

Available on the Internet as of December 2019 at: https://www.epa.gov/pmcourse/whatparticle-pollution.
Chapter 6 – References

Spring Creek Mine TR1 EA 6-9

U.S. Fish and Wildlife Service (USFWS), 2003, Migratory Bird Permit Memorandum, Subject: 

Nest Destruction. Available on the Internet as of September 2019 at: 

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the Internet as of September 2019 at: 

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U.S. Fish and Wildlife Service (USFWS), 2011, Bald Eagle Delisting. Bald Eagle Removed from 

Endangered Species List. Available on the Internet as of September 2019 at: 

http://www.fws.gov/pacific/ecoservices/BaldEagleDelisting.htm.

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the Internet as of September 2019 at: 

http://ecos.fws.gov/docs/recovery_plan/20131108%20BFF%202nd%20Rev.%20Final%20Rec

overy%20Plan.pdf.

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Available on the Internet as of September 2019 at: 

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U.S. Fish and Wildlife Service (USFWS), 2019a, List of threatened and endangered species that 

may occur in your proposed project location, and/or may be affected by your proposed 

project. Available on the Internet as of September 2019 at: 

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Migratory Bird Treaty Act, as of December 2, 2013. Available on the Internet as of 

September 2019 at: https://www.fws.gov/birds/management/managed-species/migratorybird-treaty-act-protected-species.php.

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on the Internet as of September 2019 at: 

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Mines Near Decker, Southeastern Montana: Montana Bureau of Mines and Geology 

Bulletin 97, 31 p. Electronic copy only. Available on request from OSMRE.
Chapter 6 – References

6-10 Spring Creek Mine TR1 EA

Waldhoff, S., D. Anthoff, S. Rose, and R.S.J. Tol. 2014. The Marginal Damage Costs of Different 

Greenhouse Gases: An Application of FUND. The Open-Access, Open Assessment EJournal 8(31): 1-33. http://dx.doi.org/10.5018/economics-ejournal.ja.2014-31. Available on 

the Internet as of November 2019 at: http://www.economicsejournal.org/economics/journalarticles/2014-31/version_1/at_download/file.

Western Regional Climate Center, 2020, Recent Climate in the West. Available at: 

https://wrcc.dri.edu/.

Wyoming Department of Employment, 2019, Wyoming Labor Force Trends. Employment and 

Earnings Outcomes for Wyoming CNAs. Available on the Internet as of December 2019 

at: https://doe.state.wy.us/lmi/trends/0519/0519.pdf.

Wyoming Mining Association, 2017, WYOMING COAL, The 2017-18 Concise Guide. Available 

on the Internet as of November 2019 at: http://www.wyomingmining.org/wpcontent/uploads/2013/10/2017-18-Concise-Guide-to-Wyoming-Coal.pdf.

WWC Engineering (WWC), 2019, GHG, Air Quality, and Revenue Calculations located in 

Appendix B.
APPENDIX A

REVISIONS/ERRATA, PUBLIC SCOPING DOCUMENTS,

PUBLIC REVIEW COMMENTS SUMMARY,

PUBLIC REVIEW COMMENTS LOG, and

NOTICE OF AVAILABILITY MAILING LISTS 

Spring Creek Mine TR1 EA A-1

Revisions/Errata

Title Page Revised EA date

Table of Content (TOC) The TOC has been revised to address changes in the 

document.

Section 2.1.3.4, page 1-3 This section has been added to include an additional 

alternatives considered but eliminated from detailed 

analysis.

Section 2.1.3.4, page 1-3 This section has been added to include an additional 

alternatives considered but eliminated from detailed 

analysis.

Section 3.4.1.1, page 3-2 Revised the text to update the PM10 discussions.

Section 3.4.1.4, page 3-10 Revised/added this section to address climate change.

Section 3.4.1.5, page 3-11 This section has been added to accommodate the new 

discussion on climate change (see above) and revised 

to add additional GHG discussions.

Section 3.9, page 3-19 This section has been revised to include a discussion 

on the presence of an additional vegetation species of 

concern.

Section 4.4.5.1, page 4-11 This section has been revised to update the discussion 

on GHG emissions to address a public comment.

Section 4.4.6.1, page 4-13 This section has been revised to update the discussion 

on climate change cause and effect.

Table 4-4, page 4-14 The table has been revised to add global emissions and 

to correct errors in the table.

Section 4.4.6.2, page 4-16 This section has been revised to add a discussion on 

the social cost of carbon.

Section 4.4.6.3, page 4-18 This section has been revised to add discussion of two 

additional RCP scenarios.

Section 4.5.1.1.1, page 4-21 This section has been revised to reference the 202 

CHIA.

Section 4.15.1, page 4-41 This section has been revised to add a discussion on 

the potential for train derailments.

Chapter 6 - References The Reference Section has been revised to add new 

references and to update links.

Appendix B Appendix B has been revised to add an 

Errata/Revisions table and a table of the public 

comments log.
A-2 Spring Creek Mine TR1 EA
Spring Creek Mine TR1 EA A-3
A-4 Spring Creek Mine TR1 EA
Spring Creek Mine TR1 EA A-5

Spring Creek Mine TR1 EA Public Review Comments Summary

Comment Topic

Commenter Date Address/Email Water Quality Wildlife Level of NEPA/

NEPA Process

Climate Change/Social 

Cost of Carbon Transportation

Against 

Coal 

Mining

# of 

Comments # Commenters

Western Environmental Law 

Center 03/18/20 westernlaw.org 3 5 11 11 5 1 36 1
A-6 Spring Creek Mine TR1 EA

Public Review Comment Log

Commenter Comment Final Response Final Revision

Western 

Environmental 

Law Center 

(WELC)

1. The Conservation Groups incorporate by 

reference their prior comments on the TR1 

expansion to the Montana DEQ, supplemental 

comments to Montana DEQ, and to Montana 

DEQ on Spring Creek Mine major revision.

1. As determined from Appendix B of the Final 

Environmental Impact Statement Spring Creek Mine TR1 

Project, there were 15 comments from WELC to which 

MDEQ provided responses. This EA considered the 

information in the MDEQ TR1 EIS, including the 

Conservation Groups’ comments, when preparing the final 

EA. 

1. No changes made.

2. The purpose and need statement in the 

draft EA is insufficient. It does not identify 

the statutory basis behind OSM's decision, 

including the directives under SMCRA and 

NEPA to protect the environment. The 

statement of need is equally inadequate 

because it is limited to SCC's need to 

mine coal and does not discuss any public 

needs.

2. OSMRE understands the need to accurately reflect the 

purpose and need of the EA. Therefore, OSMRE prepared 

the purpose and need statement according to CEQ’s 

regulations and Section 8.2 (Purpose and Need) of 

OSMRE’s Handbook on Implementing the National 

Environmental Policy Act, which states that that EAs “shall 

include brief discussion of the need for the proposal...” 

(40 CFR 1508.9(b). It is unclear from the comment which 

environmental directives under SMCRA and NEPA it is 

referring to but the EA, Section 1.1, notes that OSMRE 

completed the EA in accord with NEPA and the CEQ’s 

implementing regulations. Further, the EA, Section 1.3.1, 

provides that the purpose of the action is established by 

the MLA and SMCRA and that “OSMRE is the agency 

responsible for making a recommendation, supported by 

meeting all the requirements of the statutes and 

regulations listed in Section 1.4.1,to the ASLM to approve, 

disapprove, or approve with conditions the proposed 

mining plan modification.” 

2. No changes made. 

3a. The alternatives analysis is also inadequate. 

3b. The EA should discuss a middle ground 

alternative with reduced coal mining. 

3a.OSMRE understands the need to address all reasonable 

alternatives. Therefore, Section 2.1 includes a full analysis 

of all reasonable alternatives. According to NEPA 

guidance in OSMRE’s Handbook on Implementing the 

National Environmental Policy Act, an alternative is 

considered unreasonable if the “technical, economic, or 

jurisdictional obstacles make the ability to implement the 

alternative remote and speculative.” The guidance also 

states that for externally generated actions, the range of 

alternatives will typically include at least a No Action 

alternative that would proceed without approval of the 

proposed action, the applicant proposed alternative 

(proposed action), and other alternatives that would meet 

the purpose and need.

3b. OSMRE understands the need to address all reasonable 

alternatives. Inclusion of this as a viable alternative would 

3a. No changes made.

3b. An additional alternative was added to 

Section 2.1.3, Alternatives Considered but 
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Commenter Comment Final Response Final Revision

3c. The EA should also consider a clean 

energy alternative. Burning coal to make 

electricity is poisonous to people and the 

environment, and driving the large scale 

planetary crises of our time. 

limit the amount of coal tonnage and/or acreage to be 

mined to lower levels than are proposed under the 

Proposed Action. This alternative was aimed at limiting the 

direct and indirect impacts of mining, hauling, and coal 

combustion. This alternative was not considered in detail 

because it would not meet the purpose and need (see 

Section 1.3) and would be inconsistent with the MLA 

requirement to maximize recovery by achieving maximum 

economic recovery of this energy resource (43 CFR 

3480.0-5 (21)). Reducing the amount of coal reserves 

proposed to be mined would alter the proposed mine plan 

which may result in the permanent bypass of recoverable 

federal coal. OSMRE’s purpose and need is to evaluate 

SCC’s proposed mining plan modification submitted in 

accordance with the federal coal lease granted to SCC.

3c. OSMRE understands the need to address all reasonable 

alternatives. Inclusion of this as a viable alternative was 

dismissed because it is inconsistent with the project’s 

stated purpose and would not add an environmental 

benefit.

Eliminated from Detailed Analysis

3c. An additional alternative has been added to 

Section 2.1.3, Alternatives Considered but 

Eliminated from Detailed Analysis

4a. The discussion of climate impacts is wholly 

inadequate. 

4b. There is no discussion of the issue of 

climate change, which is intolerable given 

that recent research by the USGCRP, the 

IPCC, and USGS indicate that climate 

change has become a crisis and the 

window for action (rather than more of 

the same, fossil fuel extraction) is fast 

closing. 

4c. Further, the EAs discussion of climate 

change is meaningless without identifying 

4a. OSMRE understands the need to address climate impacts. 

Therefore, the EA uses sound climate information and 

current data to estimate the significance of direct, indirect, 

and cumulative impacts related to the Proposed Action 

and the no action alternative. The estimates include 

impacts from mining, transporting, and combustion of the 

coal for power generation. These estimates establish that 

the Proposed Action would not result in a significant 

increase in GHG emissions or have a significant impact 

related to climate change. 

4b. Climate change is discussed in Sections 3.4.1.4, 4.4.5, 4.4.6 

and Appendix B of the EA. The discussion in the EA 

includes consideration of and citations to many resources 

including information presented by USGCRP, IPCC and 

the USGS. 

4c. OSMRE understands the need to address climate impacts. 

OSMRE determined that the proposed project at Spring 

4a. Text has been added to Sections 4.4.5 and 

4.4.6 to contextualize cumulative impacts to 

climate from the Proposed Action.

4b. Text has been added to Sections 4.4.5 and 

4.4.6 provide additional discussions on 20-

and 100-year time horizons for emissions 

and include discussions of global GHG 

emissions

4c. Text has been revised in Section 4.4.6.3 to 

provide current information on projected 
A-8 Spring Creek Mine TR1 EA

Commenter Comment Final Response Final Revision

what level of atmospheric GHG emission 

is considered safe, what the current level 

is, what the current trajectory is, and how 

the Spring Creek Mine expansion is 

consistent or inconsistent with those level.

4d. This is critical because there is evidence 

that current GHG concentrations are not 

safe (and therefore every additional ton is 

harmful) or the remaining carbon budget 

for safe emissions is very narrow.

4e. The EA must identify a safe global 

concentration and identify the significant 

scientific controversy over what the safe 

concentration is (350 ppm, 430 ppm, 450 

ppm). 

4f. The EA must also come clean with the 

public about the negative social value of 

coal and the exorbitant social cost of 

carbon.

4g. Further, OSM's rationalizations for not 

using the social cost of carbon have been 

repeatedly debunked. As multiple courts 

have held, where, as here OSM trumpets 

economic benefits, it must also disclose 

costs.

4h. Moreover, the EA's complete failure to 

include cumulative effects and discuss 

Creek Mine would not have a significant cumulative impact 

on global GHG emissions or the global climate change 

phenomenon due to the comparatively small amount and 

short-term nature of the GHG emissions produced from 

the Federal coal in the tract.

4d. No response required.

4e. The analysis being requested is outside the scope of the 

NEPA analysis being conducted in the EA. Section 4.4.6.3 

provides the most current description of the potential 

GHG emissions scenarios from the 5th Assessment of the 

IPCC and discloses information related to those scenarios 

in the context of the Proposed Action.

4f. Section 4.4.6.2 provides OSMRE’s rationale for not 

completing the social cost of carbon protocol, To 

summarize, the information provided by the protocol for 

an individual project such as the one being analyzed in the 

EA is so variable that OSMRE determined it would not be 

useful for the decision maker or the public in 

understanding potential impacts to climate change from 

the Proposed Action.

4g. Section 4.4.6.2 provides OSMRE’s rationale for not 

completing the social cost of carbon protocol, To 

summarize, the information provided by the protocol for 

an individual project such as the one being analyzed in the 

EA is so variable that OSMRE determined it would not be 

useful for the decision maker or the public in 

understanding potential impacts to climate change from 

the Proposed Action. As explained in the EA, any 

increased economic activity expected to occur with the 

project, is simply an economic impact which could be 

viewed as negative or positive depending on perspective. 

This same approach was recently upheld in the U.S. 

District Court for the District of Montana. See 350 

Montana et al. v. Bernhardt, 2020 WL 1139674 (D. Mont.).

4h. Section 4.4.5 and 4.4.6.2 provide information on the 

cumulative effects to climate change from GHG emissions 

GHG emissions scenarios using information 

presented in the 5th Assessment of the 

IPCC.

4d. No changes made.

4e. No changes made.

4f. No changes made.

4g. No changes made.

4h. No changes made.
Spring Creek Mine TR1 EA A-9

Commenter Comment Final Response Final Revision

them is unlawful. by quantitatively discussing project-related GHG emissions 

in the context of the Powder River Basin, state, national, 

and global GHG emissions as well as providing more 

qualitative information on the sources of GHG emissions 

in the U.S.

5a. The EA also fails to discuss the impacts of 

non-GHG emissions. 

5b. OSM may not dilute these impacts to 

nothing by comparing them to total U.S. 

emissions (and if it does it must consider 

the cumulative effects of all US emissions). 

5c. Further, OSM clearly knows the exact 

locations where this coal will be burned, 

as such it must consider the effects of air 

pollution on those communities.

5a. Section 4.4.3 of the EA includes discussions of potential 

impacts related to non-GHG emissions as a result of the 

Proposed Action.

5b. Section 4.4.3 of the EA includes discussions of potential 

impacts related to non-GHG emissions in the context of 

state and national emissions as a result of the Proposed 

Action. 

5c. OSMRE does not know the future destinations and routes 

for coal mined at the Spring Creek Mine. Historical data 

for end destinations for Spring Creek coal has been 

disclosed to give perspective on potential indirect impacts. 

Per Section 3.15.2 Table 3-15, OSMRE provides 

information from the Energy Information Administration 

(EIA) that shows where coal mined at Spring Creek Mine 

has historically been transported and combusted. Using 

historical information in the EA gives the public and 

decision maker context, however, due to the variability 

described below, attempting to disclose effects to specific 

communities would be highly speculative. SCC’s coal 

contracts are entered into on a yearly basis so fluctuations 

on how much coal is transported to a given destination, or 

whether a contract with a certain customer will be 

renewed for the next year are widely variable. Looking 

through the historic data from the EIA for Spring Creek 

Mine shows that the amounts of coal delivered (and 

presumably combusted) over the past 5 years fluctuates. 

Indeed, some end users of the coal appear to have stopped 

receiving coal from Spring Creek Mine altogether in more 

recent years. Therefore, any predictions on how much 

coal and where the coal will go in the future is highly 

speculative. Due to the speculative nature of the coal 

market and associated contracts that Spring Creek enters 

into, analyzing impacts of combustion related to the 

Federal coal being mined under the Proposed Action on 

specific local areas where coal is combusted quantitatively 

would not be useful to the decision maker or public with 

regards to understanding the potential impacts of the 

5a. No changes made.

5b. No changes made.

5c. No changes made.
A-10 Spring Creek Mine TR1 EA

Commenter Comment Final Response Final Revision

Proposed Action. Section 4.15.2 provides a qualitative 

discussion of potential indirect impacts of coal transport by 

rail and Section 4.4.6.3 provides a qualitative analysis of the 

potential indirect impacts of GHG emissions from coal 

combustion. Section 4.4.3 of the EA includes discussions of 

potential impacts related to non-GHG emissions in the 

context of state and national emissions as a result of the 

Proposed Action.

6a. The EA must discuss the impacts of 

locomotive emissions on Montana 

communities, 

6b. as well as the impacts of train derailments, 

6a. Section 4.4.5 discusses CO2e emissions from coal 

transport, which include emissions from locomotives. The 

calculations are included in Appendix B. Information 

presented in these sections indicate that the Proposed 

action would not increase annual emissions from rail traffic 

but would extend the duration of emissions by 4 years. 

6b. Section 4.15.2 discusses the cumulative transportation 

impacts from the Proposed Action. Information presented 

in this section indicates that the Proposed Action would 

not increase current rail traffic but would extend the 

duration of mine-related train traffic and its potential 

effects by 4 years. The EA acknowledges the indirect 

impacts (the extension of the duration of traffic from mine 

employees, possible delays from train traffic, possible 

delays from mine equipment crossing FAS 314, and impacts 

from coal shipments using trains [public health, collisions 

with wildlife, dust, noise, and vibration] and overseas 

vessels). The local, regional, and national transportation 

facilities used to ship coal from the SCM are already in 

place. The rate of derailments is expected to be the same 

as what is currently experienced, due to the annual 

amount of coal being transported from the mine not 

increasing as a result of a decision on the Federal mining 

plan modification. Potential effects from coal train 

derailments can also vary widely depending on the scale of 

the derailment event, the surrounding environment at the 

location of the derailment, whether the derailment 

involves full or empty rail cars, and how quickly and 

thoroughly the jurisdictional authority cleans up any 

hazardous material, etc. The annual rail traffic generated by 

the Proposed Action represents an estimated 0.45 percent 

of the of the total U.S. rail freight traffic (based on 2018 

U.S. rail transportation numbers and the annual shipment 

of 14.2 Mt of coal) so the cumulative effects related to 

transportation would be minor but extended to 2031. Per 

Section 3.15.2 Table 3-15, OSMRE provides information 

6a. No changes made.

6b. General information regarding potential 

indirect impacts related to train derailments 

has been added to Section 4.15.1.
Spring Creek Mine TR1 EA A-11

Commenter Comment Final Response Final Revision

6c. and the impacts to wildlife from train 

strikes (given that OSM knows the coal 

destinations and train routes). 

from the Energy Information Administration that shows 

where coal mined at Spring Creek Mine has historically 

been transported and combusted. Coal contracts are 

worked on a yearly basis so fluctuations on how much coal 

is transported to a given destination, or whether a 

contract with a certain customer will be renewed for the 

next year are widely variable and thus highly speculative. 

Therefore, more specific predictions on possible locations 

of train derailments is also highly speculative and would 

not be useful to the decision maker or public with regard 

to understanding the potential effects of coal train 

derailments. 

6c. Section 4.15.2 discusses the cumulative transportation 

impacts from the Proposed Action. Information presented 

in this section indicates that the Proposed Action would 

not increase current rail traffic but would extend the 

duration of mine-related train traffic and its potential 

effects by 4 years. The EA acknowledges the indirect 

impacts (the extension of the duration of traffic from mine 

employees, possible delays from train traffic, possible 

delays from mine equipment crossing FAS 314, and impacts 

from coal shipments using trains [public health, collisions 

with wildlife, dust, noise, and vibration] and overseas 

vessels). The local, regional, and national transportation 

facilities used to ship coal from the SCM are already in 

place. The rate of wildlife strikes is expected to be the 

similar as what is currently experienced, due to the annual 

amount of coal being transported from the mine not 

increasing as a result of a decision on the Federal mining 

plan modification. Potential effects from coal train strikes 

can also vary widely depending on the surrounding 

environment and whether or not T&E species or their 

habitat is present at the location of the strike along with 

other factors such as large roadways being located in 

proximity to the railroad. The annual rail traffic generated 

by the Proposed Action represents an estimated 0.45 

percent of the of the total U.S. rail freight traffic (based on 

2018 U.S. rail transportation numbers and the annual 

shipment of 14.2 Mt of coal) so the cumulative effects 

related to transportation would be minor but extended to 

2031.Per Section 3.15.2 Table 3-15, OSMRE provides 

information from the Energy Information Administration 

that shows where coal mined at Spring Creek Mine has 

historically been transported and combusted. Coal 

6c. No changes made.
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Commenter Comment Final Response Final Revision

6d. Trains kill wildlife and additional trains 

from this mine will kill more wildlife. 

6e. In particular, OSM must address the 

impacts to grizzly bears, lynx, and 

threatened and endangered fish from train 

strikes, as well as cumulative impacts.

contracts are worked on a yearly basis so fluctuations on 

how much coal is transported to a given destination, or 

whether a contract with a certain customer will be 

renewed for the next year are widely variable and thus 

highly speculative. Therefore, any predictions on wildlife 

strikes is also highly speculative. Due to the speculative 

nature of the coal market and associated contracts, 

OSMRE analysis and estimates of wildlife strikes would also 

be highly speculative and would not be useful to the 

decision maker or public with regard to understanding the 

potential for wildlife strikes, 

6d.Section 4.15.2 discusses the cumulative transportation 

impacts from the Proposed Action. Information presented 

in this section indicates that the Proposed action would 

not increase current rail traffic but would extend the 

duration of mine-related train traffic by 4 years. The EA 

acknowledges the indirect impacts (the extension of the 

duration of traffic from mine employees, possible delays 

from train traffic, possible delays from mine equipment 

crossing FAS 314, and impacts from coal shipments using 

trains [public health, collisions with wildlife, dust, noise, 

and vibration] and overseas vessels). However, the local, 

regional, and national transportation facilities used to ship 

coal from the SCM are already in place and current annual 

coal production levels are not expected to change with the 

Proposed Action. The Proposed Action would extend the 

duration of mining by approximately 4 years at the SCM 

and thus the potential indirect impacts from transport of 

Federal coal by rail would be extended. The rate of wildlife 

strikes is expected to be the same as what is currently 

experienced, due to the annual amount of coal being 

transported from the mine not increasing as a result of a 

decision on the Federal mining plan modification. The 

annual rail traffic generated by the Proposed Action 

represents an estimated 0.45 percent of the total U.S. rail 

freight traffic (based on 2018 U.S. rail transportation 

numbers and the annual shipment of 14.2 Mt of coal) so 

the cumulative effects related to transportation would be 

minor but extended to 2031. 

6e. At this time, OSMRE is not aware of any information that 

would either support this claim or support the implied 

claim that trains carrying coal from the Spring Creek Mine 

have been responsible for collisions with threatened and 

6d. No changes made.

6e. No changes made.
Spring Creek Mine TR1 EA A-13

Commenter Comment Final Response Final Revision

6f. Because of the potential impacts to these 

species, OSM must consult with FWS 

under Section 7 of the Endangered Species 

Act. 

endangered species. Although the destination of the coal 

from Spring Creek Mine varies annually, historically, the 

majority of the coal transported by rail from the Spring 

Creek Mine does not go through grizzly bear or lynx 

habitat (See Map 1-3 in the EA). The EA discloses the 

potential for indirect impacts to wildlife from trains in 

Section 4.15.2. Indirect impacts resulting from 

transporting Federal coal by rail would be extended by 4 

years under the Proposed Action, but annual rail traffic is 

not expected to increase. Therefore, to the extent trains 

from Spring Creek Mine travel through grizzly bear or lynx 

habitat or the habitat of other threatened and endangered 

species (see Map 1-3 in the EA), impacts to grizzly bears 

and lynx from train strikes and to other threatened and 

endangered species from train derailments would 

continue at the same rate, but for an additional 4 years. 

6f. Because of the speculative nature of the coal market (i.e., 

where and how much coal is transported) and the 

relatively small amount of Federal coal related to this 

specific project, it is nearly impossible to quantify the 

indirect impacts to threatened and endangered species 

that occur near rail lines from transporting project-related 

coal using currently available data. Per current USFWS 

regulations in 50 CFR 402.17, in order for consequences 

of other activities caused by the proposed action to be 

considered effects of the action, both those activities and 

the consequences of those activities must satisfy a twopart test: (1) the effects would not occur but for the 

proposed action and (2) the effects are reasonably certain 

to occur. In this instance, the commenter is claiming that 

but for the approval of the proposal to mine Federal coal 

in the TR1 tract, there would be fewer wildlife strikes 

(specifically threatened and endangered species strikes) by 

trains on the railroads historically used to ship coal from 

the Spring Creek Mine. At this time, OSMRE is not aware 

of any information that would either support this claim or 

support the implied claim that trains carrying coal from the 

Spring Creek Mine have been responsible for collisions 

with threatened and endangered species. Yet, a conclusion 

of reasonably certain to occur must be based on clear and 

substantial information, using the best scientific and 

commercial data available. While it is reasonably certain to 

expect wildlife strikes by trains to occur on the same 

routes used by the trains carrying coal from the Spring 

6f. No changes made.
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Commenter Comment Final Response Final Revision

6g. Further, it is clear that OSM has not 

properly designated an action area for its 

ESA analysis. The action area must 

consider direct and indirect impacts, 

including train impacts, which are 

foreseeable. These impacts must be in 

addition to the baseline and cumulative 

effects.

Creek Mine, it is not reasonably certain that wildlife strikes 

by trains transporting Federal coal from the TR1 tract 

being considered in this EA would occur. That the wildlife 

strikes would involve a threatened and endangered species 

makes this consequence even less likely to occur. Per 50 

CFR 402.17 (b)(3) – “The consequence is only reached 

through a lengthy causal chain that involves so many steps 

as to make the consequence not reasonably certain to 

occur.” In the context of Federal coal mined from the TR1 

tract, the coal train carrying TR1 coal would need to pass 

through T&E species habitat, the species would need to be 

present in the case of wildlife strikes or otherwise 

vulnerable to impacts in the case of a derailment, the train 

would need to be there at the wrong time (generally night 

time and foraging season in the case of a grizzly bear), and 

would then have to harass or kill individuals. Due to the 

reasons stated above, OSMRE has determined that it isn’t 

necessary to consult with USFWS under Section 7 of the 

ESA.

6g. Per section 3.10.4.1, the analysis area for threatened, 

endangered and candidate species is Big Horn County. 

Due to the speculative nature of the coal market, OSMRE 

is unable to determine how much coal will be shipped to 

any specific location or what the end destination of the 

Federal coal will be.3 While it is reasonably certain to 

expect wildlife strikes by trains to occur on the same 

routes used by the trains carrying coal from the Spring 

Creek Mine, it is not reasonably certain that wildlife strikes 

by trains transporting Federal coal from the TR1 tract 

being considered in this EA would occur. That the wildlife 

strikes would involve a threatened and endangered species 

makes this consequence even less likely to occur. Per 50 

CFR 402.17 (b)(3) – “The consequence is only reached 

through a lengthy causal chain that involves so many steps 

as to make the consequence not reasonably certain to 

occur.” In the context of Federal coal mined from the TR1 

tract, the coal train carrying TR1 coal would need to pass 

6g. No changes made.

3 We note that we did use the historical average rail miles based on known past destinations and a historical annual production average to calculate air quality 

emissions from rail transport. We did this to provide data to the decision maker on the historic effects of the action; there is no assumption in the EA that the 

historical data used will predict future air quality emissions from transport.
Spring Creek Mine TR1 EA A-15

Commenter Comment Final Response Final Revision

through T&E species habitat, the species would need to be 

present in the case of wildlife strikes or otherwise 

vulnerable to impacts in the case of a derailment, the train 

would need to be there at the wrong time (generally night 

time and foraging season in the case of a grizzly bear), and 

would then have to harass or kill individuals. Due to the 

reasons stated above, OSMRE has determined that the 

analysis areas for potential direct, indirect and cumulative 

effects to T&E species is appropriate. 

7. OSM must consider impacts to Sage 

Grouse and the fact that there is no 

evidence that sage brush steppe can be 

reclaimed after strip-mining. 

See the attached WELC comments to MDEQ, 

which are incorporated here by reference, 

and discuss this issue in depth.

7. Section 4.10.3 provides detailed discussions of the direct, 

indirect, and cumulative impacts of the Proposed Action 

and the No Action alternative on Greater sage-grouse. 

SCM reclamation plans and past vegetation reclamation 

success demonstrate the vegetation communities, including 

sagebrush-steppe, can be reestablished. In addition, SCM 

cannot receive Phase III bond release until at least 10 

growing seasons after the last reclamation treatment (as 

defined in ARM 17.24.725). Phase III bond release requires 

a stable and established vegetative community that is 

consistent with the approved postmining land use, which 

would primarily be for wildlife use.

The SCM has successfully reclaimed areas with sagebrush 

and other shrubs. OSMRE recognizes coal mining 

companies that achieve exemplary coal mine reclamation 

through an annual award called The Excellence in Surface 

Coal Mining Reclamation Award. OSMRE states that 

winning projects go beyond reclamation requirements to 

achieve superior results in returning a site to productive 

use after completion of mining. SCM won the 2017 award 

based on their innovative use of soil mixtures and a variety 

of planted and seeded vegetation over a large area 

(https://www.osmre.gov/programs/awards/ActiveWinners.s

htm). The growth of a large assortment of plants led to 

greater and denser potential habitat for use by animals 

such as sage grouse, as well as songbirds, raptors, rabbits, 

mule deer, and pronghorn antelope. Also, SCM has 

demonstrated reclamation success with the approval of 

bond release application SL8 in 2015. This application 

included 407 acres for Phase III as wildlife habitat. These 

acres met the standards applicable for wildlife habitat, 

which were established based on baseline vegetation data 

in the mine and surrounding areas. Sagebrush density 

within this reclamation area had some stands exceeding 

20,000 shrubs per acre.

7. No changes made.
A-16 Spring Creek Mine TR1 EA

Commenter Comment Final Response Final Revision

8a. OSM must consider the impacts of salinity 

from spoils on the Tongue River.

8b. The river is already nearly exceeding 

salinity standards at Miles City. 

8c. This will only worsen as more saline spoils 

water discharges into the Tongue River 

Reservoir (especially in light of cumulative 

impacts from the Decker Mine and 

historical mining in Wyoming.

8a. SCM has MPDES permits in place that require surface and 

ground water discharges that leave the mine to meet 

certain standards and not have excessive salinity and 

sediment loads or impact the Tongue River Reservoir. As 

described in the 2020 TR1 Major Revision CHIA, once the 

groundwater levels stabilize in the reclaimed areas, higher 

salinity waters will temporarily flow toward discharge at 

the Tongue River. However, due to the low transmissivity 

of the sediments, the volume of water delivered is 

expected to be very small in relation to the discharge of 

the river. Because of dilution effects, no material damage is 

expected from the addition of small volumes of higher 

salinity groundwater. 

8b. TDS, SC, and SAR are water-quality constituents that 

indicate salinity. According to the 2020 TR1 Major 

Revision CHIA, TDS downstream of mining and 

downstream of the reservoir is generally similar or of 

lower concentration when compared to TDS upstream of 

mining and the reservoir. SC and SAR are similar upstream 

and downstream of mining operations. Coal mining would 

contribute cumulatively to the salinity of the Tongue River 

below the Tongue River Reservoir; however, water quality 

thresholds are applied to water discharged from the mine 

and water quality monitoring and reporting is required by 

the mining permit issued by the Montana Dept. of 

Environmental Quality (MDEQ). MDEQ enforces reported 

violations and the mine is responsible for correcting the 

cause of the violation.

8c. Mining is only one possible contributing factor for 

increased salinity in the Tongue River but long-term 

monitoring indicates that constituents that indicate salinity 

downstream of mining are at or below levels documented 

above the mining. It is apparent that current mining or the 

Proposed Action would not contribute to higher salinity 

downstream of mining.

8a. No changes made.

8b. No changes made.

8c. No changes made.
Spring Creek Mine TR1 EA A-17

Notice of Availability Mailing List

Prefix First Name Last Name Organization Name Address City State Zip

Chairman Crow Tribal Council P.O. Box 159 Crow Agency MT 59022-0159

Emerson Bull Chief Tribal Historic Preservation Officer Crow Tribe P.O. Box 159 Crow Agency MT 59022-0159

Llevando Fisher President Northern Cheyenne Tribal Council P.O. Box 128 Lame Deer MT 59043-0128

Attn Chairman Northern Cheyenne Tribe P.O. Box 128 Lame Deer MT 59043

Dave Archambault II Chairman Standing Rock Sioux Tribal Council P.O. Box D Fort Yates ND 58538

Waste 'Win Young Tribal Historic Preservation Officer Standing Rock Sioux Tribe P.O. Box D Fort Yates ND 58538

Roger Trudell Chairman Santee Sioux Tribal Council 425 Frazier Ave N Ste 2 Niobrara NE 68760-8605

Administrator Apache Tribe of Oklahoma P.O. Box 1220 Anadarko OK 73005

Cheyenne-Arapaho Tribes of Oklahoma P.O. Box 38 Concho OK 73022

Margie Murrow NAGPRA Coordinator (Acting 

Director) Comanche Nation P.O. Box 908 Lawton OK 73502

Environmental Director Kiowa Business Committee P.O. Box 369 Carnegie OK 73015

Harold Frazier Chairman Cheyenne River Sioux Tribal Council P.O. Box 590 Eagle Butte SD 57625-0590

THPO Cheyenne River Sioux Tribe P.O. Box 590 Eagle Butte SD 57625 -0590

Roxanne Sazue Tribal Council Chairman Crow Creek Sioux Tribe P.O. Box 50 Fort Thompson SD 57339-0050

Office of Cultural Preservation Flandreau Santee Sioux Tribe P.O. Box 283 Flandreau SD 57028

Lewis Grass Rope Chairman Lower Brule Sioux Tribal Council P.O. Box 187 Lower Brule SD 57548-0187

John, Yellow Bird Steele President Oglala Sioux Tribal Council P.O. Box 2070 Pine Ridge SD 57770-2070

THPO Oglala Sioux Tribe P.O. Box 320 Pine Ridge SD 57770-2070

Russell Eagle Bear Rosebud Sioux THPO P.O. Box 809 Rosebud SD 57570

William Kindle President Rosebud Sioux Tribal Council P.O. Box 430 Rosebud SD 57570-0430

Cultural Resource Coordinator Rosebud Sioux Tribe P.O. Box 675 Mission SD 57555-0675

Chairman Arapahoe Business Council P.O. Box 396 Fort Washakie WY 82514-0396

Director of Cultural Preservation Eastern Shoshone Tribe P.O. Box 1008 Fort Washakie WY 82514

Darlene Conrad THPO Northern Arapaho Business Council P.O. Box 396 Fort Washakie WY 82514-0396

Chairman Shoshone Business Council P.O. Box 538 Fort Washakie WY 82514-0538
A-18 Spring Creek Mine TR1 EA

First Name Last Name Organization Name Address City State Zip

BLM Library P.O. Box 25047 Denver CO 80225-0047

Environmental Protection Specialist National Park Service - Air Quality P.O. Box 25287 Denver CO 80225-0287

Matt McKeown Rocky Mtn Region Solicitor 755 Parfet St Ste 151 Lakewood CO 80215-5599

Peter Morgan Sierra Club 1650 38th Street, Suite 

102W Boulder CO 80301

Taylor Jones WildEarth Guardians 1536 Wynkoop Street, Suite 

301 Denver CO 80202

Jeremy Nichols WildEarth Guardians 2590 Walnut Street Denver CO 80205

Advisory Council on Historic Preservation 401 F Street NW, Suite 308 Washington DC 20001-2637

Mitchell Leverette-Division Chief BLM WO320 20 M Street SE Washington DC 20003

Don Sutherland Bureau of Indian Affairs 1849 C St NW Stop 4516 Washington DC 20240-0001

Defenders of Wildlife 1130 17th Street, NW Washington DC 20036-4604

Phillips Baker National Mining Association 101 Constitution Ave NW 

Ste 500E Washington DC 20001-2133

NPS 2310 1849 C St NW Stop 2749 Washington DC 20240-0001

U.S. Department of Energy 1000 Independence Ave. SW Washington DC 20585-0001

US EPA 1200 Pennsylvania Ave., NW 

MC 1701A, Rm 3413 ARN Washington DC 20460

Dan Roane 268 Bristol St Northfield IL 60093

Jason M. Ryan Business Analytics Director US Western Surface Operations 701 Market Street, 6th Floor St. Louis MO 63101

Big Horn Conservation District 724 W 3rd Hardin MT 59034

Weed Control Supervisor Big Horn County 636 West Second Hardin MT 59034

Commissioners Big Horn County P.O. Box 908 Hardin MT 59034

Michael Gulledge Billings Gazette P.O. Box 36300 Billings MT 59107-6300

Jamie Connell-State Director BLM Montana State Office 5001 Southgate Drive Billings MT 59101

Coal Coordinator BLM Montana State Office 5001 Southgate Drive Billings MT 59101-4669

Darryl LaCounte Regional Director Bureau of Indian Affairs 2021 4th Ave N #200 Billings MT 59101

Superintendent Bureau of Indian Affairs-Crow Agency P.O. Box 69 Crow Agency MT 59022

District Manager Bureau of Land Management 111 Garryowen Road Miles City MT 59301

Custer Gallatin National Forest 10 E. Babcock Street Bozeman MT 59715

Water Protection Bureau Department of Environmental Quality 1520 E. 6th Ave. Helena MT 59620

Air Resources Management Department of Environmental Quality - Air 

Resources Management 1520 E. 6th Ave. Helena MT 59620

Regional Supervisor Department of Fish, Wildlife & Parks 2300 Lake Elmo Drive Billings MT 59105

Regional Supervisor Department of Fish, Wildlife and Parks P.O. Box 1630 Miles City MT 59301
Spring Creek Mine TR1 EA A-19

First Name Last Name Organization Name Address City State Zip

Safety Bureau Department of Labor and Industry 1805 Prospect Ave. Helena MT 59624

Administrator Department of Natural Resources and Conservation 

- Water Resources Division 1625 Eleventh Ave. Helena MT 59620

Administrator Department of Natural Resources and Conservation 

- Trust Land Management Division 1625 Eleventh Ave. Helena MT 59620

Jenny Harbine Earthjustice 313 E. Main Street Bozeman MT 59715

Steve Bullock Governor of Montana State Capitol Bldg, P.O. Box 

200801 Helena MT 59620-0001

Doug McRae Greenleaf Livestock 3952 Rosebud Cr. Road Forsyth MT 59327

Andrew C. Emrich, P.C. Holland & Hart, LLP 6380 S. Fiddlers Green 

Circle, Suite 500

Greenwood 

Village CO 80111

Greg Julian Dept of Nat Res & Conservation

Mineral Management Service P.O. Box 201601 Helena MT 59620-1601

Montana Association of Counties 2715 Skyway Drive Helena MT 59602

Montana State Historic Preservation Office 1301 East Lockey Avenue Helena MT 59620

Rae Peppers MT State Representative House District 41 P.O. Box 497 Lame Deer MT 59043-0497

Sharon Stewart-Peregoy MT State Representative House District 42 P.O. Box 211 Crow Agency MT 59022-0211

Jason Small MT State Senator Senate District 21 HC 42 Box 560 Busby MT 59016-9703

Philip S. Strobel NEPA US Environmental Protection Agency Region 8 1595 Wynkoop Denver CO 80202

Northern Cheyenne Cultural Commission P.O. Box 128 Lame Deer MT 59043-0128

Natalie Snyders Northern Plains Resource Council 220 S 27th Street Ste A Billings MT 59101

Kate French Northern Plains Resource Council 220 S 27th Street Ste A Billings MT 59101

Bob LeResche Northern Plains Resource Council 220 S 27th Street Ste A Billings MT 59101

Steve Bullock, Governor Office of the Governor State of Montana P.O. Box 200801 Helena MT 59620

Mike Scott Sierra Club 2401 Montana Avenue Ste 4 Billings MT 59101

Stuart Sanderson, President The Colorado Mining Association 216 16th Street, Suite 1250 Denver CO 80202

Keith Williams, Group President Thunder Basin Coal Company P.O. Box 406 Wright WY 82732

US Army Corps of Engineers, Omaha District 10 W. 15th Street, Ste 2200 Helena MT 59626

Brian Smith US Army Corps of Engineers, Omaha District P.O. Box 2256 Billings MT 59103

US Environmental Protection Agency 10 West 15th Street Ste 

3200 Helena MT 59626

Ecological Services US Fish and Wildlife Service 585 Shepard Way, Suite 1 Helena MT 59601

US Geological Survey 3162 Bozeman Avenue Helena MT 59601

State Office US Natural Resources Conservation Service 10 East Babcock Bozeman MT 59715

Greg Gianforte US Representative-Montana 7 West 6th Avenue Helena MT 59601
A-20 Spring Creek Mine TR1 EA

First Name Last Name Organization Name Address City State Zip

Jon Tester US Senator-Montana 208 N Montana Avenue, 

Suite 202 Helena MT 59601

Steve Daines US Senator-Montana P.O. Box 1598 Helena MT 59624

Clint McRae 3633 Rosebud Cr. Road Forsyth MT 59327

Daniel Hadley 730 E. Main Ste 106 Billings MT 59105

Montana Environmental Information Center P.O. Box 1184 Helena MT 59624

Don Bailey 6111 Masters Blvd Billings MT 59106

Shiloh Hernandez Western Environmental Law Center 208 Paseo del Pueblo Sur 

Unit 602 Taos NM 87571

Beth Goodnough Western Fuels Association 1901 Energy Court, Suite 

328 Gillette WY 82718

Jane Thomas Wyoming Analytical Laboratories, Inc. 1660 Harrison Street Laramie WY 82070

Eric Barlow Wyoming House of Representatives House District 3 

VIA EMAIL Eric.Barlow@wyoleg.gov

Administrator Apache Tribe of Oklahoma P.O. Box 1220 Anadarko OK 73005

Amy M. Atwood Center for Biological Diversity P.O. Box 11374 Portland OR 97211-0374

BNSF Railway Company P.O. Box 961057 Fort Worth TX 76161-0057

National Wildlife Federation 11100 Wildlife Center Drive Reston VA 20190

Division of Habitat Resource 

Conservation US Fish & Wildlife Service 5275 Leesburg Pike, Mail Stop: HRC Falls Church VA 22041

Managing Editor Associated Press 320 W 25th St Ste 310 Cheyenne WY 82001

Biodiversity Conservation Alliance P.O. Box 1512 Laramie WY 82073-1512

Mayor City of Sheridan 55 Grinnell Plaza Sheridan WY 82801

Darryl Maunder Navajo Transitional Energy Company P.O. Box 3009 Gillette WY 82717

Shannon Anderson Powder River Basin Resource Council 934 North Main Street Sheridan WY 82801

County Engineer Sheridan County 224 South Main Ste B-1 Sheridan WY 82801

Mayor City of Sheridan City Hall 55 Grinnell Plaza Sheridan WY 82801

Roger Miller-President Trout Unlimited 334 N. Main Street Sheridan WY 82801

Mark Rogaczewski WDEQ Land Quality Division 2100 West 5th Street Sheridan WY 82801-6136

Jack Fritz WWC Engineering 1849 Terra Ave Sheridan WY 82801-6112

Wyoming Mining Association 1401 Air Port Parkway Suite 

230 Cheyenne WY 82001

Alan & Jimmie Pierce HC 59 Box 10A Decker MT 59025

Albert & Debra Pierce 960 6th Avenue E Sheridan WY 82801
Spring Creek Mine TR1 EA A-21

First Name Last Name Organization Name Address City State Zip

Fidelity Exploration California Street, Suite 2500 

80202 1700 Lincoln St, Suite 2800 Denver CO 80203

Florence Young HC 59 Box 15 Decker MT 59025

James & Margoriem Hamilton HC 59 Box 13 Decker MT 59025

Jeanette M Davis 1815 N Mariposa Ln Billings MT 59102

Jodi & Tom Edwards HC 42 Box 642 Busby MT 59016

Kevin Smith Department of Natural Resources and Conservation 1625 11th Avenue Helena MT 59601

Lane Larson P.O. Box 531 Sheridan WY 82801

Mark & Mary Kay Van Haele HC 59 Box 11B Decker MT 59025

Montana Rail Link P.O. Box 16390101 Missoula MT 59808

Frances Schultz Schultz Coal Co./Wolf Mountain Coal 191 Seymore St. Sheridan WY 82801

Bill Pruitt Decker Coal Company 12 Lakeshore Drive Decker MT 59025

Todd Yeager Bureau of Land Management 111 Garryowen Road Miles City MT 59301

Walter J. & Lila V. Taylor HC 42 Box 595 Busby MT 59016

David Lagesse Bison Connect VIA EMAIL justdavengwen@comcast.net

D. Steven Degenfelder 4491 Sunrise Drive Casper WY 82604

Robert K. Green 19005 Arabian Lane Frenchtown MT 59834

Keith Walters 8 Bozeman Lane Ranchester WY 82839

Gordon Box Bison Connect VIA EMAIL woodchuckwy@msn.com
APPENDIX B

CALCULATIONS of

GREENHOUSE GAS EMISSIONS;

PM10, PM2.5, SO2, NOX, Hg, CO, and CO2 CONTRIBUTIONS from MINING; 

and 

EMISSIONS from COAL COMBUSTION

(Completed by WWC Engineering)
Spring Creek Mine TR1 EA B-1

GHG Calculations Assumptions 

Direct Emissions Variables

Source CO2e/Mt Coal Mined

Fuel Subtotal 1,963.5

Electricity Subtotal 3,188.4

Process Subtotal 577.4

Source: WWC Calculation 2019

Indirect Transportation Emissions Assumptions

120 Tons of Coal/Car

130 Cars/Train

15,600 Tons of Coal/Train

24 Tons/car empty1/2 are 22 tons and 1/2 are 26 tons

200 Tons/locomotivehttp://www.4rail.net/reference_nam_bnsf_locos1.php

3,920 Weight of empty 130/car train (tons)

19,520 Weight of loaded coal train (tons)

0.00000978 Tonnes CO2 per ton-mile coal from Vessels

4,300 One-way barge miles

36 Barge trips

Transportation Emissions Variables (Locomotives)

Emission Rate (kg/gal) 100-year Time Horizon CO2e 

Conversion Rate

20-year Time Horizon 

CO2e Conversion Rate Kg CO2e/Gal Diesel Kg CO2e/Mile/Ton

CO2 10.21 1 1 10.21 0.023417431

CH4 0.0008 28 84 0.0200 0.000001

N2O 0.00026 264 265 0.07748 0.000016

Total 10.30748 0.0234

Source: Conversion Rate – EPA 2017a

Emission Rate – EPA 2014

Transportation Variables (Locomotives)

Miles/gal/1 Ton1 Miles Kg 

CO2e/Mile/Ton2

Tons Kg CO2e /Mile Kg CO2e/Trip Metric Tons CO2e/Trip

Loaded 436 1,042 0.0234 19,520.0 457.4 476,641.7 476.6

Empty 436 1,042 0.0234 3,920 91.9 95,719.0 95.7

1 FactCheck 2008

2

EPA 2014

SCM Production, 2014-2018

2014 2015 2016 2017 2018 2014-2018 Average

Production (Tons) 17,324,830 16,987,420 10,259,276 12,732,724 13,768,055 14,214,461

Source: SCM 2019
B-2 Spring Creek Mine TR1 EA

Estimated 2005 Annual Spring Creek Mine CO2e (in metric tons)

Estimated 2005 Spring Creek Mine Equivalent CO2e (in 

metric tons)

Source Ave. Known 

Ratio

Coal 

(mm Tons)

Fuel 25,760 1963.5 13.12

Electricity 41,830 3188.4

Mining Process 7,575 577.4

Haulage 508,133

Total at Mine 583,298

2005 Average Coal Haulage 

2005 Coal Production 13,119,202

Tons Coal/Train 15,600

Empty Train Tons 3,920

Loaded Train Tons 19,520

# Loaded Trains/year 841

# Empty Trains/year 841

Rail miles to power plant 1,100

Kg CO2e/Mi/Loaded Train 457.43

Kg CO2e/Mi/Empty Train 91.86

Kg CO2e/year Empty 84,977,919.5

Kg CO2e/year Loaded 423,155,354.3

Kg CO2e/year Total 508,133,273.8

Metric Tons CO2e/year 508,133.3

CO2e Source Year

2005

Direct Emissions

 Fuel 25,760

 Electricity 41,830

 Mining Process 7,575

 Total Direct Emissions 75,165

Indirect Emissions

 Haulage 508,133

 Power Plant Combustion 26,802,530

 Total Indirect Emissions 27,310,663

Total Emissions 27,385,828
Spring Creek Mine TR1 EA B-3

Estimated 2014-2018 Average Annual Spring Creek Mine CO2e (in metric tons)

Source Coal (Mt)

Ave. Known Ratio 

(metric tons CO2e/Mt 

coal)

100-year Time 

Horizon Metric 

Tons CO2e

20-year Time 

Horizon Metric 

Tons CO2e

Direct

Fuel 14.21 1,963.5 27,910 28,052

Electricity 3,188.4 45,322 45,553

Mining Process 577.4 8,208 8,250

Total Direct 81,440 81,855

Indirect

Transport 100-year Time Horizon 20-year Time Horizon

2014-2018 Coal Production 14,214,461 14,214,461

Tons Coal/Train 15,600 15,600

Empty Train Tons 3,920 3,920

Loaded Train Tons 19,520 19,520

# Loaded Trains/year 911 911

# Empty Trains/year 911 911

Average Rail miles to power plant 1,144 1,144

Kg CO2e/Mi/Loaded Train 457.43 459.72

Kg CO2e/Mi/Empty Train 91.86 92.32

Kg CO2e/year Empty 95,755,209.5 96,233,985.53

Kg CO2e/year Loaded 476,821,859.5 479,205,968.75

Rail Kg CO2e/year Total 572,577,068.9 575,439,954.27

Rail Metric CO2e/year Total 572,577.1 575,439.95

Average Annual Overseas Shipments 3,708,000.0 3,708,000.0

Round Trip Barge Shipment Miles 9,900.0 9,900.0

Total Vessel Emissions (Metric Tons) 358,871.1 360,665.5

Transport Metric Tons CO2e/year 931,448 936,188

Combustion (Tons CO2e) 29,792,278 29,943,871

Total Indirect CO2e (Tons) 30,723,727 30,880,058

Total Direct + Indirect CO2e 30,805,167 30,961,913
Appendix B

B-4 Spring Creek Mine TR1 EA

Estimated 2020-2031 Spring Creek Mine CO2e (in metric tons)

Source Coal (Mt) Ave. Known Ratio (tons 

CO2e/Mt coal)

100-year Time 

Horizon Metric 

Tons CO2e

20-year Time 

Horizon Metric 

Tons CO2e

Direct

Fuel 14.20 1,963.5 27,882 28,024

Electricity 3,188.4 45,276 45,506

Mining Process 577.4 8,200 8,241

Total Direct 81,357 81,771

Indirect

Transport 100-year Time Horizon 20-year Time Horizon

2020-2031 Coal Production 14,200,000 14,200,000

Tons Coal/Train 15,600 15,600

Empty Train Tons 3,920 3,920

Loaded Train Tons 19,520 19,520

# Loaded Trains/year 910 910

# Empty Trains/year 910 910

Average Rail miles to power plant 1,210 1,210

Kg CO2e/Mi/Loaded Train 457.43 459.7

Kg CO2e/Mi/Empty Train 91.86 92.3

Kg CO2e/year Empty 101,176,512.3 101,682,394.9

Kg CO2e/year Loaded 503,817,734.8 506,336,823.5

Rail Kg CO2e/year Total 604,994,247.2 608,019,218.4

Rail Metric CO2e/year Total 604,994.2 608,019.2

Average Annual Overseas Shipments 4,500,000 4,500,000

Round Trip Barge Shipment Miles 9,900 9,900

Total Vessel Emissions (Metric Tons) 435,523.2 437,700.8

Transport Metric Tons CO2e/year 1,040,517 1,045,812

Combustion (Tons CO2e) 29,792,278 29,943,871

Total Indirect CO2e (Tons) 30,832,796 30,989,683

Total Direct + Indirect CO2e 30,914,153 31,071,454
Appendix B

Spring Creek Mine TR1 EA B-5

Parameters Used to Calculate Combustion Emissions

Btu per short ton 24,930,000

tons per kilogram 0.00110231

tons to generate 1Kilowatt-Hour 0.00052

tons to generate 1 Megawatt-Hour 0.52

PM10 Emissions per Btu (kilogram per MegawattHour) 0.39

PM10 Emissions per Btu (ton per Megawatt-Hour) 0.000429901

PM2.5 Emissions per Btu (kilogram per MegawattHour) 0.305

PM2.5 Emissions per Btu (ton per Megawatt-Hour) 0.00013112

SO2 Emissions per Btu (kilogram per Megawatt-Hour) 7.192

SO2 Emissions per Btu (ton per Megawatt-Hour) 0.007927814

NOx Emissions per Btu (kilogram per MegawattHour) 2.779

NOx Emissions per Btu (ton per Megawatt-Hour) 0.003063319

Hg Emissions per Btu (kilogram per Megawatt-Hour) 0.000028

Hg Emissions per Btu (ton per Megawatt-Hour) 0.00000003

CO Emissions (lb) per ton 0.50000000

Combustion Emissions Values

Emissions Combustion Past Production Proposed

Action

No 

Action

Total U.S. 

Emissions

2020-2031 

Average 

% of U.S.

Years 2014 2015 2016 2017 2018 2014-2018 2020-

2031

2020-

2031 -- --

Tons mined (From SCC) 17,324,830 16,987,420 10,259,276 12,732,724 13,768,055 14,214,461 14,200,000 14,200,000 -- --

mw-h from coal mined 9,008,912 8,833,458 5,334,824 6,621,016 7,159,389 7,391,520 7,384,000 7,384,000 -- --

PM10 Emissions (Tons) 3,872.9 3,797.5 2,293.4 2,846.4 3,077.8 3,177.6 3,174.4 3,174.4 20,616,000 0.02%

PM2.5 Emissions (Tons) 1,181.2 1,158.2 699.5 868.1 938.7 969.2 968.2 968.2 6,033,000 0.02%

SO2 Emissions (Tons) 71,421.0 70,030.0 42,293.5 52,490.2 56,758.3 58,598.6 58,539.0 58,539.0 4,991,000 1.17%

NOX Emissions (Tons) 27,597.2 27,059.7 16,342.3 20,282.3 21,931.5 22,642.6 22,619.6 22,619.6 12,412,000 0.18%

Hg Emissions (Tons) 0.28 0.27 0.16 0.20 0.22 0.23 0.23 0.23 52 0.44%

CO Emissions (Tons) 4,331.2 4,246.9 2,564.8 3,183.2 3,442.0 3,553.6 3,550.0 3,550.0 52,483,810 0.01%
APPENDIX C

2018 4th QUARTER and ANNUAL SPRING CREEK MINE 

GROUNDWATER MONITORING RESULTS
Spring Creek Mine TR1 EA C-1
C-2 Spring Creek Mine TR1 EA

Spring Monitoring Sample Analytical Results

Analyte Units Applicable Water 

Quality Criteria (1)

Rainy Spring (Grab)

12/7/2017

Field Duplicate 

FDSW1SA18 

12/7/2017

3/2/2018

Physical Parameters

pH s.u. 8.2 8.2 8.2

Conductivity mho/cm 2460 2450 2430

Total Dissolved Solids (TDS) [180] mg/L 2130 2100 2060

Common Ions

Alkalinity (total as CaCO3) mg/L 502 502 570

Hardness (total as CaCO3) mg/L 1250 1250 1230

Bicarbonate (as HCO3) mg/L 613 613 696

Carbonate (as CO3) mg/L ND [5] ND [5] ND [5]

Calcium mg/L 179 179 168

Magnesium mg/L 194 194 196

Potassium mg/L 12 12 10

Sodium mg/L 137 138 132

Chloride mg/L 8 8 11

Fluoride mg/L 4.0 0.4 0.4 0.4

Sodium Adsorption Ratio (SAR) 1.7 1.7 1.6

Sulfate mg/L 1120 1080 1030

Nutrients

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 ND [0.02] ND [0.02] ND [0.02]

Nitrogen, Ammonia (as N) mg/L ND [0.07] ND [0.07] 0.0244J

Dissolved Metals

Aluminum mg/L 0.02J 0.0203J 0.0158J

Arsenic mg/L 0.01 0.000585J, J-B 0.000551J, J-B 0.000428J

Boron mg/L 0.13 0.13 0.12

Cadmium mg/L 0.005 ND [0.0005] ND [0.0005] 0.000219J

Copper mg/L 1.3 0.00134J, J-B 0.00119J, J-B 0.000815J

Iron mg/L 0.05 0.05 0.00861J

Lead mg/L 0.015 ND [0.0003] ND [0.0003] 0.0000942J

Manganese mg/L 0.032 0.031 0.111

Nickel mg/L 0.1 0.002 0.002 0.003

Selenium mg/L 0.05 0.003 0.002 0.000886J

Vanadium mg/L 0.000621J 0.000740J 0.000676J

Zinc mg/L 2.0 ND [0.008] ND [0.008] ND [0.008]

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter 

mg/L - milligrams per liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). 

J - Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit. 

J-B - Analyte detected in associated field blank and sample result is less than 10 times the blank concentration.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality, updated October 2012.

Shaded cells indicate an exceedance of the applicable criteria.
Spring Creek Mine TR1 EA C-3

Mainstem Spring Creek Stream Sample Analytical Results

Analyte Units

Montana Numeric

Water Quality 

Criteria (1)

CB-2 (Grab) CB-2 (Autosampler)

3/15/2018 6/20/2018

Physical Parameters

pH s.u. 6.5-9.0 (2) 8.0

Conductivity mho/cm 500 (3) 212

Total Dissolved Solids (TDS) [180] mg/L 160

Total Suspended Solids (TSS) mg/L 8 1130

Turbidity NTU (4) 10.7

Oil & Grease mg/L ND [3.11]

Common Ions

Alkalinity (total as CaCO3) mg/L 69

Hardness (total as CaCO3) mg/L 70

Bicarbonate (as HCO3) mg/L 84

Carbonate (as CO3) mg/L ND [5]

Calcium mg/L 14

Magnesium mg/L 9

Potassium mg/L 12

Sodium mg/L 6

Chloride mg/L 2

Fluoride mg/L 4.0 (5) 0.0476J

Sodium Adsorption Ratio (SAR) 3.0-7.5 (3) 0.29

Sulfate mg/L 27

Nutrients

Total Nitrogen as N (ammonium + 

nitrate/nitrite + organic nitrogen) mg/L 2

Total Phosphorous (inorganic + organic) mg/L 0.62

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 (5) 0.08

Nitrogen, Ammonia (as N) mg/L (6) 0.42

Dissolved Metals

Aluminum mg/L 0.087 0.11

Arsenic mg/L 0.000579J

Boron mg/L 0.0212J

Cadmium mg/L 0.000119J

Copper mg/L 0.003

Iron mg/L 0.12

Lead mg/L 0.0000623J

Manganese mg/L 0.03

Nickel mg/L ND [0.002]

Selenium mg/L 0.000222J

Vanadium mg/L 0.00112J

Zinc mg/L ND [0.008]

Total Recoverable Metals

Aluminum mg/L 0.19

Arsenic mg/L 0.15 0.000716J

Boron mg/L 0.0289J

Cadmium mg/L (7) 0.000193J

Copper mg/L (7) 0.003

Iron mg/L 1.0 0.27

Lead mg/L (7) 0.0003

Manganese mg/L 0.037

Nickel mg/L (7) 0.000581J

Selenium mg/L 0.005 ND [0.001]

Vanadium mg/L 0.000794J

Zinc mg/L (7) 0.00704J

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L 

- milligrams per liter

NTU - Nephelometric turbidity units

-- = not analyzed

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J -

Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit.

(1) - Because the surface water monitoring station is located on an undisturbed channel, criteria are presented for comparison only and do not represent

water quality limits at Spring Creek Mine. Per ARM 17.30.611(1)(c), onsite streams are classified as C-3 and therefore criteria listed are from DEQ-7 in accordance 

with ARM 17.30.629(2)(h) and represent an appropriate comparison. Further, comparison criteria represent surface water - chronic aquatic life standards (except 

where noted) for additional conservativeness.

(2) - See narrative standard in ARM 17.30.629(2)(c)

(3) - See narrative standard in ARM 17.30.670(4)

(4) - See narrative standard in ARM 17.30.629(2)(d); maximum allowable increase above naturally occurring turbidity is 10 NTU.

(5) - No numeric chronic aquatic life standard available--criteria shown represents human health standards in surface water.

(6) - Criteria are temperature and pH-based (see DEQ-7, Note [7]); compared to chronic criterion (CCC), fish early life stages 

absent.

(7) - Criteria are hardness-based (see DEQ-7, Note [12]).

Shaded cells represent an exceedance of the comparison criteria.
C-4 Spring Creek Mine TR1 EA

South Fork Spring Creek Stream Sample Analytical Results

Analyte Units

Montana Numeric 

Water Quality 

Criteria (1)

SF-1R (Grab) SF-1R (Autosampler)

5/25/2018 5/25/2018

Physical Parameters

pH s.u. 6.5-9.0 (2) 8.3

Conductivity mho/cm 500 (3) 2430

Total Dissolved Solids (TDS) [180] mg/L 2020

Total Suspended Solids (TSS) mg/L 3 10

Turbidity NTU (4) 2.1

Oil & Grease mg/L ND [3.11]

Common Ions

Alkalinity (total as CaCO3) mg/L 549

Hardness (total as CaCO3) mg/L 1230

Bicarbonate (as HCO3) mg/L 670

Carbonate (as CO3) mg/L ND [5]

Calcium mg/L 186

Magnesium mg/L 187

Potassium mg/L 15

Sodium mg/L 122

Chloride mg/L 10

Fluoride mg/L 4.0 (5) 0.4

Sodium Adsorption Ratio (SAR) 3.0-7.5 (3) 1.5

Sulfate mg/L 1030

Nutrients

Total Nitrogen as N (ammonium + nitrate/nitrite +

organic nitrogen) mg/L 1.1

Total Phosphorous (inorganic + organic) mg/L 0.05

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 (5) 0.14

Nitrogen, Ammonia (as N) mg/L (6) 0.08

Dissolved Metals

Aluminum mg/L 0.087 0.026J

Arsenic mg/L 0.002

Boron mg/L 0.12

Cadmium mg/L 0.000313J

Copper mg/L 0.003

Iron mg/L 0.0171J

Lead mg/L 0.0001J

Manganese mg/L 0.296

Nickel mg/L ND [0.002]

Selenium mg/L 0.003

Vanadium mg/L 0.000815J

Zinc mg/L 0.00366J

Total Recoverable Metals

Aluminum mg/L 0.0422J

Arsenic mg/L 0.15 0.002

Boron mg/L 0.13

Cadmium mg/L (7) 0.0001

Copper mg/L (7) 0.002

Iron mg/L 1.0 0.1

Lead mg/L (7) 0.0000334J

Manganese mg/L 0.302

Nickel mg/L (7) 0.005

Selenium mg/L 0.005 0.003

Vanadium mg/L 0.000744J

Zinc mg/L (7) 0.013

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

NTU - Nephelometric turbidity units

-- = not analyzed

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J -

Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit.

(1) - Because the surface water monitoring stations are located on an undisturbed channel, criteria are presented for comparison only

and do not represent water quality limits at Spring Creek Mine. Per ARM 17.30.611(1)(c), onsite streams are classified as C-3 and 

therefore criteria listed are from DEQ-7 in accordance with ARM 17.30.629(2)(h) and represent an appropriate comparison. Further, 

comparison criteria represent surface water- chronic aquatic life standards (except where noted) for additional conservativeness.

(2) - See narrative standard in ARM 17.30.629(2)(c)

(3) - See narrative standard in ARM 17.30.670(4)

(4) - See narrative standard in ARM 17.30.629(2)(d); maximum allowable increase above naturally occurring turbidity is 10 NTU.

(5) - No numeric chronic aquatic life standard available--criteria shown represents human health standards in surface water.

(6) - Criteria are temperature and pH-based (see DEQ-7, Note [7]); compared to chronic criterion (CCC), fish early life stages absent.

(7) - Criteria are hardness-based (see DEQ-7, Note [12]).

Shaded cells represent an exceedance of the comparison criteria.
Spring Creek Mine TR1 EA C-5

Reclaimed South Fork Spring Creek Stream Sample Analytical Results

Analyte Units

Montana Numeric

Water Quality 

Criteria (1)

RS-8 (Grab) RS-8 (Autosampler) RS-8 (Grab)

3/14/2018 5/30/2018 6/22/2018

Physical Parameters

pH s.u. 6.5-9.0 (2) 7.8 8.4

Conductivity mho/cm 500 (3) 84 1870

Total Dissolved Solids (TDS) [180] mg/L 100 1550

Total Suspended Solids (TSS) mg/L 5 93 4

Turbidity NTU (4) 9.2 2.6

Oil & Grease mg/L ND [3.11] ND [3.11]

Common Ions

Alkalinity (total as CaCO3) mg/L 40 231

Hardness (total as CaCO3) mg/L 30 821

Bicarbonate (as HCO3) mg/L 49 274

Carbonate (as CO3) mg/L ND [5] 4J

Calcium mg/L 8 124

Magnesium mg/L 3 124

Potassium mg/L 7 23

Sodium mg/L 0.86J 129

Chloride mg/L 0.78J 9

Fluoride mg/L 4.0 (5) 0.046J 0.2

Sodium Adsorption Ratio (SAR) 3.0-7.5 (3) ND [0.01] 1.96

Sulfate mg/L 0.844J 855

Nutrients

Total Nitrogen as N (ammonium + nitrate/nitrite

+ organic nitrogen) mg/L 1.5 1.4

Total Phosphorous (inorganic + organic) mg/L 0.25 0.12

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 (5) 0.17 0.017J

Nitrogen, Ammonia (as N) mg/L (6) 0.11 0.057J

Dissolved Metals

Aluminum mg/L 0.087 0.08 0.00855J

Arsenic mg/L 0.000612J 0.002

Boron mg/L 0.0212J 0.07

Cadmium mg/L 0.000181J 0.000086J

Copper mg/L 0.002 ND [0.002]

Iron mg/L 0.09 0.14

Lead mg/L 0.000148J ND [0.0003]

Manganese mg/L 0.006 0.088

Nickel mg/L 0.00169J 0.003

Selenium mg/L 0.000208J 0.000842J

Vanadium mg/L 0.000345J 0.000869J

Zinc mg/L 0.00378J 0.015

Total Recoverable Metals

Aluminum mg/L 0.08 0.0448J

Arsenic mg/L 0.15 0.000379J 0.002

Boron mg/L 0.0192J 0.07

Cadmium mg/L (7) 0.000231J 0.000384J

Copper mg/L (7) 0.002 ND [0.002]

Iron mg/L 1.0 0.1 0.3

Lead mg/L (7) 0.000166J 0.0004

Manganese mg/L 0.007 0.088

Nickel mg/L (7) ND [0.002] 0.003

Selenium mg/L 0.005 ND [0.001] 0.001

Vanadium mg/L 0.000577J 0.00121J

Zinc mg/L (7) ND [0.008] 0.026

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

NTU - Nephelometric turbidity units

-- = not analyzed

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J -

Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit.

(1) - Because the surface water monitoring stations are located on an undisturbed channel, criteria are presented for comparison only

and do not represent water quality limits at Spring Creek Mine. Per ARM 17.30.611(1)(c), onsite streams are classified as C-3 and therefore criteria 

listed are from DEQ-7 in accordance with ARM 17.30.629(2)(h) and represent an appropriate comparison. Further, comparison criteria represent 

surface water - chronic aquatic life standards (except where noted) for additional conservativeness.

(2) - See narrative standard in ARM 17.30.629(2)(c)

(3) - See narrative standard in ARM 17.30.670(4)

(4) - See narrative standard in ARM 17.30.629(2)(d); maximum allowable increase above naturally occurring turbidity is 10 NTU.

(5) - No numeric chronic aquatic life standard available--criteria shown represents human health standards in surface water.

(6) - Criteria are temperature and pH-based (see DEQ-7, Note [7]); compared to chronic criterion (CCC), fish early life stages absent.

(7) - Criteria are hardness-based (see DEQ-7, Note [12]).

Shaded cells represent an exceedance of the comparison criteria.
C-6 Spring Creek Mine TR1 EA

Pearson Creek Stream Sample Analytical Results

Analyte Units

Montana Numeric

Water Quality 

Criteria (1)

PC-1ST (First 

Stage Sample

Bottle)

PC-2 

(Autosampler)

3/23/2018 6/21/2018

Physical Parameters

pH s.u. 6.5-9.0 (2)

Conductivity mho/cm 500 (3)

Total Dissolved Solids (TDS) [180] mg/L

Total Suspended Solids (TSS) mg/L 29 1260

Turbidity NTU (4)

Oil & Grease mg/L

Common Ions

Alkalinity (total as CaCO3) mg/L

Hardness (total as CaCO3) mg/L

Bicarbonate (as HCO3) mg/L

Carbonate (as CO3) mg/L

Calcium mg/L

Magnesium mg/L

Potassium mg/L

Sodium mg/L

Chloride mg/L

Fluoride mg/L 4.0 (5)

Sodium Adsorption Ratio (SAR) 3.0-7.5 (3)

Sulfate mg/L

Nutrients

Total Nitrogen as N (ammonium + nitrate/nitrite

+ organic nitrogen) mg/L

Total Phosphorous (inorganic + organic) mg/L

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 (5)

Nitrogen, Ammonia (as N) mg/L (6)

Dissolved Metals

Aluminum mg/L 0.087

Arsenic mg/L

Boron mg/L

Cadmium mg/L

Copper mg/L

Iron mg/L

Lead mg/L

Manganese mg/L

Nickel mg/L

Selenium mg/L

Vanadium mg/L

Zinc mg/L

Total Recoverable Metals

Aluminum mg/L

Arsenic mg/L 0.15

Boron mg/L

Cadmium mg/L (7)

Copper mg/L (7)

Iron mg/L 1.0

Lead mg/L (7)

Manganese mg/L

Nickel mg/L (7)

Selenium mg/L 0.005

Vanadium mg/L

Zinc mg/L (7)

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

NTU - Nephelometric turbidity units

-- = not analyzed

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J -

Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit.

(1) - Because the surface water monitoring stations are located on undisturbed channels, criteria are presented for comparison only and do not represent water quality limits at Spring Creek 

Mine. Per ARM 17.30.611(1)(c), onsite streams are classified as C-3 and therefore criteria listed are from DEQ-7 in accordance with ARM 17.30.629(2)(h) and represent an appropriate 

comparison. Further, comparison criteria represent surface water - chronic aquatic life standards (except where noted) for additional conservativeness.

(2) - See narrative standard in ARM 17.30.629(2)(c)

(3) - See narrative standard in ARM 17.30.670(4)

(4) - See narrative standard in ARM 17.30.629(2)(d); maximum allowable increase above naturally occurring turbidity is 10 NTU.

(5) - No numeric chronic aquatic life standard available--criteria shown represents human health standards in surface water.

(6) - Criteria are temperature and pH-based (see DEQ-7, Note [7]).

(7) - Criteria are hardness-based (see DEQ-7, Note [12]).

Shaded cells represent an exceedance of the comparison criteria.
Spring Creek Mine TR1 EA C-7

South Fork Spring Creek Flood Control Reservoir Sample Analytical Results

Analyte Units

Montana Numeric

Water Quality 

Criteria (1)

South Fork Flood Control Reservoir (Grab)

3/2/2018

Field Duplicate

FDS1SA18B 

3/2/2018

6/21/2018

Field Duplicate

FDS2SA18 

6/21/2018

Physical Parameters

pH s.u. 6.5-9.0 (2) 8.2 8.2 8.4 8.4

Conductivity mho/cm 500 (3) 2450 2450 2030 2030

Total Dissolved Solids (TDS) [180] mg/L 2140 2050 1620 1640

Total Suspended Solids (TSS) mg/L 25 J-P 12 J-P 2 2

Turbidity NTU (4) 6.5 J-P 5 J-P 1.0 1.1

Oil & Grease mg/L ND [3.11] ND [3.11] ND [3.11] ND [3.11]

Common Ions

Alkalinity (total as CaCO3) mg/L 510 495 418 403

Hardness (total as CaCO3) mg/L 1290 1260 1050 1030

Bicarbonate (as HCO3) mg/L 623 604 477 459

Carbonate (as CO3) mg/L ND [5] ND [5] 16 16

Calcium mg/L 176 171 152 149

Magnesium mg/L 207 202 162 160

Potassium mg/L 10 10 14 14

Sodium mg/L 138 132 105 104

Chloride mg/L 9 10 8 8

Fluoride mg/L 4.0 (5) 0.4 0.4 0.4 0.4

Sodium Adsorption Ratio (SAR) 3.0-7.5 (3) 1.66 1.62 1.41 1.4

Sulfate mg/L 1150 1120 847 853

Nutrients

Total Nitrogen as N (ammonium + 

nitrate/nitrite + organic nitrogen) mg/L 0.5, J-B 0.6, J-B 0.8 0.8

Total Phosphorous (inorganic + organic) mg/L 0.03 0.02 0.02 0.02

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 (5) 0.03 0.03 ND [0.02] ND [0.02]

Nitrogen, Ammonia (as N) mg/L (6) 0.0196J, J-B 0.0292J, J-B 0.08, J-B 0.032J, J-B

Dissolved Metals

Aluminum mg/L 0.087 0.0185J 0.0199J 0.00884J 0.008J

Arsenic mg/L 0.000281J 0.00022J 0.000842J 0.000846J

Boron mg/L 0.1 0.1 0.09 0.09

Cadmium mg/L 0.000158J, J-B 0.000179J, J-B ND [0.0005] ND [0.0005]

Copper mg/L 0.000718J 0.000711J 0.000855J 0.000848J

Iron mg/L 0.0119J 0.00964J ND [0.02] ND [0.02]

Lead mg/L 0.0000495J, J-B 0.0000241J, J-B 0.000132J, J-B 0.000108J, J-B

Manganese mg/L 0.086 0.079 0.062 0.061

Nickel mg/L 0.00104J ND [0.002] 0.00155J 0.002

Selenium mg/L 0.004 0.003 0.002 0.002

Vanadium mg/L 0.000917J, J-B 0.000745J, J-B 0.000934J 0.000584J

Zinc mg/L ND [0.008] ND [0.008] ND [0.008] ND [0.008]

Total Recoverable Metals

Aluminum mg/L 0.22 0.16 0.0376J, J-B 0.0351J, J-B

Arsenic mg/L 0.15 0.000626J 0.00039J 0.001 0.001

Boron mg/L 0.12 0.13 0.1 0.14

Cadmium mg/L (7) 0.000454J, J-B 0.000498J, J-B 0.000068J 0.0000538J

Copper mg/L (7) 0.005 0.002 ND [0.002] ND [0.002]

Iron mg/L 1.0 0.42 J-P 0.31 J-P 0.05 0.04

Lead mg/L (7) 0.0005, J-B 0.0003, J-B ND [0.0003] ND [0.0003]

Manganese mg/L 0.122 0.112 0.078 0.081

Nickel mg/L (7) 0.00153J, J-B 0.00183J, J-B 0.003 J-B 0.002 J-B

Selenium mg/L 0.005 0.004 0.004 0.002 0.002

Vanadium mg/L 0.000718J 0.000681J ND [0.01] 0.000308J

Zinc mg/L (7) 0.067 J-P, J-B 0.04 J-P, J-B ND [0.008] ND [0.008]

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

NTU - Nephelometric turbidity units

-- = not analyzed

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J -

Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit. J-B -

Analyte detected in associated field blank and sample result is less than 10 times the blank concentration.

J-P - Relative percent difference between primary and field duplicate samples exceeded quality criteria threshold of 25%.

(1) - Because the pond monitoring station in this table represents water from upstream of the mine, criteria are presented for comparison only and do not represent water quality limits at Spring Creek Mine. Per

ARM 17.30.611(1)(c), onsite streams are classified as C-3 and therefore criteria listed are from DEQ-7 in accordance with ARM 17.30.629(2)(h) and represent an appropriate comparison. Further, comparison

criteria represent surface water- chronic aquatic life standards (except where noted) for additional conservativeness.

(2) - See narrative standard in ARM 17.30.629(2)(c)

(3) - See narrative standard in ARM 17.30.670(4)

(4) - See narrative standard in ARM 17.30.629(2)(d); maximum allowable increase above naturally occurring turbidity is 10 NTU.

(5) - No numeric chronic aquatic life standard available--criteria shown represents human health standards in surface water.

(6) - Criteria are temperature and pH-based (see DEQ-7, Note [7]); compared to chronic criterion (CCC), fish early life stages absent.

(7) - Criteria are hardness-based (see DEQ-7, Note [12]).

Shaded cells represent an exceedance of the comparison criteria.
C-8 Spring Creek Mine TR1 EA

Overburden / Burn (Clinker) Groundwater Sample Analytical Results

Analyte Units Applicable Water 

Quality Criteria (1)

CL-3 CL-4 CL-7 CL-8 OB-4

2/28/2018 2/28/2018 7/24/2018 3/27/2018 7/19/2018 2/26/2018 7/18/2018 7/24/2018

Physical Parameters

pH s.u. 8.2 8.1 8.1 8.0 8.2 8.3 8.2 8.4

Conductivity mho/cm 672 1210 762 3210 3210 850 831 2020

Total Dissolved Solids (TDS) [180] mg/L 390 770 460 2900 2940 550 570 1290

Common Ions

Alkalinity (total as CaCO3) mg/L 111 539 356 469 493 281 275 1060

Hardness (total as CaCO3) mg/L 241 490 366 1470 1510 351 336 85

Bicarbonate (as HCO3) mg/L 135 658 435 572 601 343 335 1250

Carbonate (as CO3) mg/L ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] 23

Calcium mg/L 42 90 74 175 183 75 72 15

Magnesium mg/L 33 65 44 251 255 40 38 12

Potassium mg/L 6 9 8 15 15 8 7 6

Sodium mg/L 31 71 21 238 257 41 39 506

Chloride mg/L 5 3 1 11 10 8 7 10

Fluoride mg/L 4.0 0.7 0.7 0.6 0.7 0.7 1.3 1.3 2.7

Sodium Adsorption Ratio (SAR) 0.9 1.4 0.5 2.7 2.9 1.0 0.9 23.8

Sulfate mg/L 196 152 66 1600 1540 158 149 76

Nutrients

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 0.2 0.04 ND [0.02] 1.53 1.37 1.44 1.29 0.22

Nitrogen, Ammonia (as N) mg/L 0.0556J 0.1 0.29 ND [0.07] 0.0114J 0.0117J ND [0.07] 0.55

Dissolved Metals

Aluminum mg/L ND [0.05] 0.0204J 0.78 0.0305J 0.0273J 0.0231J 0.0227J 0.1

Arsenic mg/L 0.01 0.000218J 0.000483J 0.005 0.006 0.005 0.015 0.018 0.000445J

Boron mg/L 0.12 0.18 0.14 0.17 0.14 0.39 0.39 0.08

Cadmium mg/L 0.005 0.000131J 0.000087J 0.0006 0.000117J 0.000286J 0.000095J 0.000415J 0.000421J

Copper mg/L 1.3 ND [0.002] 0.000532J 0.00185J 0.003 0.0015J 0.004 0.000921J 0.00199J

Iron mg/L 3.23 0.17 3.57 0.0173J 0.0191J 0.09 0.07 0.08

Lead mg/L 0.015 ND [0.0003] ND [0.0003] 0.0013 0.0000893J 0.0000474J ND [0.0003] 0.0000632J 0.000218J

Manganese mg/L 0.464 0.191 3.03 0.029 0.029 0.009 0.012 0.059

Nickel mg/L 0.1 ND [0.002] 0.008 0.022 0.002 0.0017J 0.002 0.003 0.005

Selenium mg/L 0.05 0.00064J 0.000275J 0.000656J 0.009 0.008 0.006 0.008 0.000138J

Vanadium mg/L 0.000879J 0.00191J 0.00552J 0.07 0.06 0.3 0.37 0.000428J

Zinc mg/L 2.0 ND [0.008] 0.00737J 0.00356J ND [0.008] ND [0.008] 0.00606J 0.00393J 0.018

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J -

Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality, updated October 2012.

Shaded cells indicate an exceedance of the applicable criteria.
Spring Creek Mine TR1 EA C-9

Anderson-Dietz Coal Groundwater Sample Analytical Results

Analyte Units

Applicable Water 

Quality Criteria (1)

2107-80 403WA 404W

A

504AQ

W

507AQ

W

508AQ

W

3/28/2018 7/19/2018 3/23/2018 7/20/2018 3/28/2018 7/19/2018 2/27/2018 7/18/2018 2/26/2018 7/18/2018 2/26/2018 7/18/2018

Physical Parameters

pH s.u. 8.2 8.2 8.4 8.4 8.3 8.4 8.2 8.2 8.3 8.3 8.3 8.3

Conductivity mho/cm 4280 4230 2450 2650 3090 3040 1210 1210 975 1010 2500 2810

Total Dissolved Solids (TDS) [180] mg/L 3680 3510 1690 1800 2170 2060 820 840 720 720 1960 1980

Common Ions

Alkalinity (total as CaCO3) mg/L 581 578 694 705 972 1040 370 388 276 256 1160 1210

Hardness (total as CaCO3) mg/L 1220 1280 302 360 246 251 499 500 376 358 379 369

Bicarbonate (as HCO3) mg/L 709 705 822 822 1170 1220 451 474 330 310 1380 1480

Carbonate (as CO3) mg/L ND [5] ND [5] 12 18 9 27 ND [5] ND [5] 3J 1J 14 ND [5]

Calcium mg/L 193 203 50 60 38 39 104 103 72 67 48 46

Magnesium mg/L 181 189 43 51 37 38 58 59 48 46 63 62

Potassium mg/L 34 33 9 10 11 10 13 13 12 11 21 21

Sodium mg/L 614 611 507 545 639 691 59 65 74 79 585 606

Chloride mg/L 12 11 5 5 11 10 54 54 19 13 15 16

Fluoride mg/L 4.0 0.7 0.8 1.5 1.3 1.1 1.1 0.9 0.8 1.2 1.2 1.1 1.0

Sodium Adsorption Ratio (SAR) 7.6 7.4 12.7 12.5 17.7 19.0 1.1 1.3 1.7 1.8 13.1 13.7

Sulfate mg/L 1980 1840 600 678 679 606 201 197 246 243 420 412

Nutrients

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 0.28 0.47 ND [0.02] 0.01J ND [0.02] ND [0.02] 0.04 0.02 0.04 0.09 ND [0.02] ND [0.02]

Nitrogen, Ammonia (as N) mg/L ND [0.07] 0.0253J 2.72 2.43 1.70 1.48 0.0418J 0.0153J 0.0447J 0.0081J 0.61 0.54

Dissolved Metals

Aluminum mg/L 0.0419J 0.0486J 0.0159J 0.0437J 0.0235J 0.019J 0.0424J 0.0391J 0.08 0.0145J 0.0335J 0.0367J

Arsenic mg/L 0.01 0.000464J 0.001 0.000217J 0.000267J 0.000769J 0.000694J 0.005 0.005 0.008 0.009 0.000415J 0.000626J

Boron mg/L 0.47 0.34 0.12 0.09 0.15 0.09 0.16 0.2 0.16 0.16 0.25 0.25

Cadmium mg/L 0.005 0.000208J 0.0005 0.000378J 0.000292J 0.000107J 0.000232J 0.000108J 0.000465J 0.000256J 0.000407J 0.000185J 0.0019

Copper mg/L 1.3 0.003 0.000667J 0.000209J ND [0.002] ND [0.002] 0.004 0.000444J ND [0.002] 0.00151J ND [0.002] 0.000809J 0.042

Iron mg/L 0.00797J 0.02 0.34 0.08 1.25 0.04 0.006J 0.00441J 0.03 0.00522J 0.23 0.27

Lead mg/L 0.015 ND [0.0003] 0.00000792J 0.000144J 0.00011J ND [0.0003] 0.0000806J ND [0.0003] ND [0.0003] 0.000128J ND [0.0003] ND [0.0003] 0.0036

Manganese mg/L 0.00254J 0.011 0.01 0.016 0.048 0.042 0.022 0.011 0.00333J 0.006 0.026 0.025

Nickel mg/L 0.1 0.005 0.000984J ND [0.002] 0.002 0.003 0.00111J 0.00136J 0.003 0.005 ND [0.002] 0.003 ND [0.002]

Selenium mg/L 0.05 0.000204J 0.000389J 0.000615J ND [0.001] 0.000152J ND [0.001] 0.000407J 0.000396J 0.000438J 0.000517J 0.000834J 0.000383J

Vanadium mg/L 0.00295J 0.01 0.000497J ND [0.01] 0.000851J 0.00264J 0.02 0.03 0.03 0.04 0.00119J ND [0.01]

Zinc mg/L 2.0 0.00335J 0.00243J 0.01 0.00167J ND [0.008] ND [0.008] 0.00359J 0.00476J 0.0029J ND [0.008] ND [0.008] ND [0.008]

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J - Estimated value; analyte was positively

detected above the method detection limit but below the laboratory reporting limit. J-B - Analyte detected in associated field blank and sample result isless than 10 times the

blank concentration.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality, updated October 2012.

Shaded cellsindicate an exceedance of the applicable criteria.
C-10 Spring Creek Mine TR1 EA

Anderson-Dietz Coal Groundwater Sample Analytical Results (Continued)

Analyte Units

Applicable Water 

Quality Criteria (1)

509AQ

W

AD-4 AD-6 AD-7 AD-9 AD-14

2/26/2018 7/18/2018 4/11/2018 7/23/2018 3/27/2018 7/20/2018 3/27/2018 7/20/2018 2/26/2018 7/19/2018 3/28/2018 7/19/2018

Physical Parameters

pH s.u. 8.2 8.1 8.2 8.2 8.4 8.6 9.0 8.9 8.1 8.2 7.9 8.0

Conductivity mho/cm 1180 1230 1420 1460 3430 3590 1800 1780 2530 2620 7760 8280

Total Dissolved Solids (TDS) [180] mg/L 820 850 950 970 2360 2470 1130 1110 2180 2220 7640 8320

Common Ions

Alkalinity (total as CaCO3) mg/L 335 320 390 405 870 860 969 971 451 434 511 517

Hardness (total as CaCO3) mg/L 476 480 297 285 32 31 11 12 1170 1210 2570 2770

Bicarbonate (as HCO3) mg/L 409 390 476 494 1020 977 983 1030 551 530 623 631

Carbonate (as CO3) mg/L ND [5] ND [5] ND [5] ND [5] 21 36 98 78 ND [5] ND [5] ND [5] ND [5]

Calcium mg/L 85 85 65 62 7 7 2 3 140 143 360 376

Magnesium mg/L 64 65 33 32 4 3 1 1 200 206 405 446

Potassium mg/L 12 12 18 18 9 8 5 5 17 17 48 49

Sodium mg/L 75 80 204 240 806 835 463 473 178 187 1080 1010

Chloride mg/L 61 58 4 4 5 6 3 3 8 8 31 33

Fluoride mg/L 4.0 1.0 1.0 0.1 0.2 1.7 1.8 1.9 2.0 0.7 0.7 0.5 0.5

Sodium Adsorption Ratio (SAR) 1.5 1.6 5.2 6.2 61.9 65.2 59.6 59.9 2.3 2.3 9.3 8.4

Sulfate mg/L 246 243 344 352 939 942 40 46 1150 1120 4600 4470

Nutrients

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 ND [0.02] ND [0.02] 0.11 0.011J ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] 0.03

Nitrogen, Ammonia (as N) mg/L 0.0274J 0.0186J 2.49 2.85 2.71 2.22 1.62 1.49 0.033J, J-B 0.0591J 8.26 8.82

Dissolved Metals

Aluminum mg/L 0.0199J 0.0142J 0.0197J 0.0259J 0.00458J 0.00701J 0.0194J 0.0118J 0.0211J 0.017J 0.11 0.11

Arsenic mg/L 0.01 0.006 0.007 0.000094J 0.000663J ND [0.001] 0.0001J 0.00013J 0.000133J 0.004 0.004 0.0000831J 0.000654J

Boron mg/L 0.09 0.09 0.09 0.1 J-B 0.09 0.04 0.05 0.05 0.13 0.14 1.16 0.7

Cadmium mg/L 0.005 0.000131J 0.00044J 0.000124J 0.000137J, J-B 0.000132J 0.0003J 0.000187J 0.000259J 0.000179J, J-B 0.0003J 0.000189J 0.0014

Copper mg/L 1.3 0.000227J ND [0.002] 0.00144J ND [0.002] ND [0.002] ND [0.002] 0.000147J ND [0.002] 0.000136J, J-B ND [0.002] ND [0.002] ND [0.002]

Iron mg/L 0.34 0.29 0.05 0.62 2.87 2.01 0.06 0.08 0.09 0.09 4.12 2.14

Lead mg/L 0.015 ND [0.0003] ND [0.0003] ND [0.0003] 0.000161J 0.00000851J 0.0000102J 0.000249J 0.0000445J ND [0.0003] 0.0000482J ND [0.0003] 0.0006

Manganese mg/L 0.019 0.018 0.073 0.098 0.025 0.027 0.01 0.006 0.042 0.046 0.112 0.119

Nickel mg/L 0.1 0.002 0.00179J 0.00094J 0.004 ND [0.002] ND [0.002] ND [0.002] ND [0.002] 0.00133J 0.003 0.009 ND [0.002]

Selenium mg/L 0.05 ND [0.001] ND [0.001] ND [0.001] 0.000192J 0.000331J 0.000368J 0.005 0.007 0.000254J ND [0.001] 0.00034J 0.000415J

Vanadium mg/L 0.00109J 0.00135J 0.000501J 0.000139J 0.000529J 0.00058J 0.000515J 0.000153J 0.00116J 0.00182J 0.00115J 0.00492J

Zinc mg/L 2.0 ND [0.008] ND [0.008] 0.012 0.00659J ND [0.008] ND [0.008] 0.02 0.016 ND [0.008] 0.00288J ND [0.008] ND [0.008]

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J - Estimated value; analyte was positively

detected above the method detection limit but below the laboratory reporting limit. J-B - Analyte detected in associated field blank and sample result isless than 10 times the

blank concentration.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality, updated October 2012.

Shaded cellsindicate an exceedance of the applicable criteria.
Spring Creek Mine TR1 EA C-11

Anderson-Dietz Coal Groundwater Sample Analytical Results (Continued)

Analyte Units

Applicable Water 

Quality Criteria (1)

AD-15 AD-16 AD-17 AD-18 CBM02-3DC

2/26/2018

Field Duplicate 

FD1SA18A 

2/26/2018

7/23/2018 3/27/2018 7/20/2018 4/11/2018 7/19/2018 2/26/2018 7/19/2018 2/28/2018 7/24/2018

Physical Parameters

pH s.u. 8.3 8.3 8.4 8.3 8.4 8.6 8.5 8.2 8.3 8.7 8.8

Conductivity mho/cm 845 844 856 4650 4710 1940 1900 2170 2200 1220 1260

Total Dissolved Solids (TDS) [180] mg/L 590 580 580 3340 3360 1230 1040 1810 1820 780 800

Common Ions

Alkalinity (total as CaCO3) mg/L 171 171 176 862 870 1110 1070 382 383 640 640

Hardness (total as CaCO3) mg/L 324 324 326 108 109 25 30 963 981 29 30

Bicarbonate (as HCO3) mg/L 206 208 211 1030 1030 1240 1230 466 467 672 706

Carbonate (as CO3) mg/L 1J ND [5] 2J 11 15 51 36 ND [5] ND [5] 54 37

Calcium mg/L 48 48 46 25 25 6 7 119 121 7 7

Magnesium mg/L 50 50 51 11 11 3 3 162 165 3 3

Potassium mg/L 9 10 9 13 11 6 4 16 16 4 4

Sodium mg/L 50 49 48 1100 1100 507 509 148 149 315 315

Chloride mg/L 4 6 4 21 21 6 6 7 7 3 4

Fluoride mg/L 4.0 1.3 1.2 1.3 2.8 2.7 2.1 1.9 0.7 0.8 2.2 2.1

Sodium Adsorption Ratio (SAR) 1.2 1.2 1.2 46.2 46.0 43.8 40.3 2.1 2.1 25.4 25.0

Sulfate mg/L 261 261 258 1600 1560 21 20 944 905 58 55

Nutrients

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 1.04 1.04 0.97 1.00 2.23 0.04 ND [0.02] 0.22 0.22 ND [0.02] ND [0.02]

Nitrogen, Ammonia (as N) mg/L ND [0.07] ND [0.07] 0.0216J, J-B 0.22 0.0211J 1.50 1.71 0.0078J, J-B 0.012J 0.59 0.72

Dissolved Metals

Aluminum mg/L 0.0147J 0.0134J 0.0153J 0.07 0.0445J 0.27 0.26 0.019J 0.0165J 0.31 0.17

Arsenic mg/L 0.01 0.008 0.008 0.009 0.0000831J 0.000374J 0.001 0.001 0.006 0.006 0.00068J 0.001

Boron mg/L 0.18 0.18 0.18 J-B 0.1 0.07 0.07 0.06 0.13 0.13 0.05 0.08

Cadmium mg/L 0.005 0.000089J, J-B 0.000094J, J-B 0.000101J, J-B 0.000229J 0.0007 0.000101J 0.000236J 0.000107J, J-B 0.000295J 0.000134J 0.000448J

Copper mg/L 1.3 0.00144J, J-B 0.00123J, J-B 0.000729J 0.00182J 0.000278J 0.00115J 0.000568J 0.00031J, J-B 0.000684J 0.006 0.00125J

Iron mg/L 0.000851J 0.00146J 0.00246J 0.03 0.02 0.26 0.59 0.17 0.11 0.51 0.11

Lead mg/L 0.015 ND [0.0003] ND [0.0003] 0.0000655J ND [0.0003] 0.00013J 0.0003 0.0011 ND [0.0003] 0.0000261J 0.0005 0.000153J

Manganese mg/L 0.000948J 0.000977J 0.00092J 0.039 0.00315J 0.033 0.038 0.025 0.017 0.011 0.006

Nickel mg/L 0.1 ND [0.002] ND [0.002] 0.00196J ND [0.002] 0.003 0.002 ND [0.002] 0.002 ND [0.002] 0.013 0.008

Selenium mg/L 0.05 0.004 0.004 0.005 0.000535J 0.000348J ND [0.001] ND [0.001] 0.001 0.001 0.000179J 0.000143J

Vanadium mg/L 0.1 0.09 0.11 0.000793J 0.000511J 0.00116J 0.00219J 0.1 0.11 0.00118J 0.000919J

Zinc mg/L 2.0 0.00234J 0.00291J ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] 0.00254J 0.00776J ND [0.008]

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J - Estimated value; analyte was positively

detected above the method detection limit but below the laboratory reporting limit. J-B - Analyte detected in associated field blank and sample result isless than 10 times the

blank concentration.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality, updated October 2012.

Shaded cellsindicate an exceedance of the applicable criteria.
C-12 Spring Creek Mine TR1 EA

Interburden/Underburden Groundwater Sample Analytical Results

Analyte Units Applicable Water

Quality Criteria 

(1)

81-115-

IBW

UB-2

2/26/2018 7/18/2018 4/11/2018 7/23/2018

Physical Parameters

pH s.u. 8.5 8.6 8.9 8.9

Conductivity mho/c

m

1610 1820 2060 2070

Total Dissolved Solids (TDS) [180] mg/L 1090 1200 1380 1380

Common Ions

Alkalinity (total as CaCO3) mg/L 791 794 254 293

Hardness (total as CaCO3) mg/L 30 34 62 63

Bicarbonate (as HCO3) mg/L 914 905 266 318

Carbonate (as CO3) mg/L 26 32 22 19

Calcium mg/L 8 8 11 12

Magnesium mg/L 3 3 8 8

Potassium mg/L 6 6 9 8

Sodium mg/L 430 456 442 459

Chloride mg/L 15 14 5 5

Fluoride mg/L 4.0 4.5 4.6 2.3 2.4

Sodium Adsorption Ratio (SAR) 34.5 34.1 24.5 25.1

Sulfate mg/L 114 157 697 701

Nutrient

Nitrogen, Nitrate s -Nitrite (as N) mg/L 10.0 0.09 0.05 ND [0.02] ND [0.02]

Nitrogen, Ammonia (as N) mg/L 1.26 1.31 2.52 2.62

Dissolved Metals

Aluminum mg/L 0.1 0.06 0.0113J 0.0364J

Arsenic mg/L 0.01 0.000238J 0.000245J 0.000258J 0.000318J

Boron mg/L 0.05 0.06 0.3 0.34

Cadmium mg/L 0.005 0.000184J 0.000423J 0.000182J 0.000113J, J-B

Copper mg/L 1.3 0.003 0.000848J 0.000354J 0.00175J

Iron mg/L 0.38 0.04 0.08 0.26

Lead mg/L 0.015 0.0000893J 0.0000682J 0.000037J 0.0004

Manganese mg/L 0.018 0.011 0.008 0.015

Nickel mg/L 0.1 0.000834J 0.00159J 0.00197J 0.00186J

Selenium mg/L 0.05 ND [0.001] ND [0.001] 0.001 0.000182J

Vanadium mg/L 0.000789J 0.000171J 0.000819J 0.00123J

Zinc mg/L 2.0 ND [0.008] 0.00394J 0.009 0.035

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L - milligrams per liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J - Estimated value; analyte was positively detected 

above the method detection limit but below the laboratory reporting limit. J-B - Analyte detected in associated field blank and sample result is less than 10 times the blank 

concentration.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality, updated October 2012.

Shaded cells indicate an exceedance of the applicable criteria.
Spring Creek Mine TR1 EA C-13

Canyon Coal Groundwater Sample Analytical Results

Analyte Units

Applicable 

Water Quality 

Criteria (1)

CBM02-3CC CN-1A CN-5 CN-7

2/28/2018 7/24/2018 2/27/2018 7/23/2018

Field Duplicate

FD2SA18B 

7/23/2018

2/26/2018 7/18/2018

Field 

Duplicate 

FD2SA18A 

7/18/2018

2/26/2018 7/18/2018

Physical Parameters

pH s.u. 12.5 12.4 8.5 8.6 8.6 8.5 8.5 8.5 8.5 8.6

Conductivity mho/cm 7180 6360 1620 1640 1640 1950 1970 1970 1780 1790

Total Dissolved Solids (TDS) [180] mg/L 1420 1370 1040 1030 1030 1280 1320 1320 1110 1140

Common Ions

Alkalinity (total as CaCO3) mg/L 1610 1550 554 548 545 614 634 615 1050 1000

Hardness (total as CaCO3) mg/L 823 796 14 14 14 16 16 16 18 16

Bicarbonate (as HCO3) mg/L ND [5] ND [5] 645 627 624 710 735 712 1200 1130

Carbonate (as CO3) mg/L 40 54 15 20 20 19 19 19 40 43

Calcium mg/L 330 319 4 4 4 4 4 4 4 4

Magnesium mg/L ND [1] 0.0319J 1 1 1 1 1 1 2 1

Potassium mg/L 18 18 4 4 4 5 4 5 6 5

Sodium mg/L 323 329 402 403 400 488 456 493 475 475

Chloride mg/L 62 65 3 3 3 6 6 6 14 7

Fluoride mg/L 4.0 0.3 0.3 2.8 2.9 2.8 4.0 4.0 3.8 4.6 5.0

Sodium Adsorption Ratio (SAR) 4.9 5.1 47.6 46.9 46.2 53.2 50.4 54.3 48.8 52.4

Sulfate mg/L 6 1 269 265 264 367 359 359 7 3

Nutrients

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02]

Nitrogen, Ammonia (as N) mg/L 2.71 2.52 1.12 1.05 1.02 1.23 1.13 1.19 1.6 1.54

Dissolved Metals

Aluminum mg/L 0.56 0.51 0.00976J ND [0.05] 0.00479J 0.06 0.0294J 0.0278J 2.81 0.18

Arsenic mg/L 0.01 0.000337J 0.000425J ND [0.001] ND [0.001] 0.0000792J 0.000138J 0.000268J 0.000261J 0.0004J 0.000279J

Boron mg/L 0.04 0.06 0.03 0.06 J-B 0.05 J-B 0.05 0.06 0.06 0.06 0.06

Cadmium mg/L 0.005 0.000278J 0.001 0.000075J 0.000089J, J-B 0.000104J, J-B 0.000089J 0.000435J 0.000422J 0.000066J, J-B 0.000395J

Copper mg/L 1.3 0.01 0.005 0.00121J ND [0.002] 0.000765J 0.00187J ND [0.002] ND [0.002] 0.000642J, J-B ND [0.002]

Iron mg/L 0.0192J 0.0173J 0.03 0.02 0.03 0.07 0.05 0.05 1.14 0.14

Lead mg/L 0.015 0.0029 0.0006 ND [0.0003] 0.0000226J 0.0000351J ND [0.0003] 0.0000678J 0.00000564J 0.0018 0.001

Manganese mg/L ND [0.005] 0.000863J 0.00322J 0.00368J 0.0047J 0.005 0.005 0.00482J 0.017 0.005

Nickel mg/L 0.1 0.000814J 0.007 0.00122J 0.002 0.0016J 0.00144J ND [0.002] ND [0.002] 0.00121J ND [0.002]

Selenium mg/L 0.05 0.000385J 0.000331J ND [0.001] 0.000136J ND [0.001] ND [0.001] 0.000212J 0.000164J ND [0.001] ND [0.001]

Vanadium mg/L 0.000576J 0.000955J 0.000401J 0.000336J 0.000518J 0.000878J 0.00136J 0.0012J 0.0021J ND [0.01]

Zinc mg/L 2.0 ND [0.008] ND [0.008] 0.00411J ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008]

Notes:

s.u. - standard units

μmho/cm - micromhos per centimeter mg/L -

milligrams per liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in parentheses). J -

Estimated value; analyte was positively detected above the method detection limit but below the laboratory reporting limit. J-B - Analyte

detected in associated field blank and sample result is less than 10 times the blank concentration.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality,

updated October 2012.

Shaded cells indicate an exceedance of the applicable criteria.
C-14 Spring Creek Mine TR1 EA

Reclaimed Spoils Groundwater Sample Analytical Results

Notes:

s.u. - standard units

μmho/cm - micromhos per 

centimeter mg/L - milligrams per 

liter

ND [0.01] - Indicates analyte was not detected above the laboratory reporting limit (laboratory reporting limit in

parentheses). J - Estimated value; analyte was positively detected above the method detection limit but below the

laboratory reporting limit.

(1) - Unless otherwise noted, criteria listed are Groundwater - Human Health Standards from Circular DEQ-7, Montana Department of Environmental Quality, updated October 2012.

Shaded cells indicate an exceedance of the applicable criteria.

Analyte Units

Applicable Water 

Quality Criteria (1)

SP-1 SP-2 SP-3 SP-4 SP-6 SP-7

2/26/2018 7/18/2018 2/27/2018

Field 

Duplicate 

FD1SA18B 

2/27/2018

7/20/2018 2/26/2018 7/20/2018 3/2/2018 7/20/2018 3/2/2018 7/19/2018 2/26/2018 7/18/2018

Physical Parameters

pH s.u. 8.1 8.0 7.6 7.8 7.9 8.1 8.0 7.7 7.8 7.9 8.1 7.9 8.0

Conductivity mho/cm 4940 5290 6250 6270 6160 6120 6430 4720 4390 6490 5350 9460 10400

Total Dissolved Solids (TDS) [180] mg/L 4060 3920 5940 5920 5390 4900 4600 3930 3620 5300 3870 8520 8480

Common Ions

Alkalinity (total as CaCO3) mg/L 1620 1620 1160 1180 1200 2040 1980 575 600 1380 1030 3070 3070

Hardness (total as CaCO3) mg/L 570 586 2480 2400 2480 394 410 1300 898 1090 769 979 972

Bicarbonate (as HCO3) mg/L 1980 1980 1420 1440 1470 2490 2420 702 732 1680 1260 3750 3750

Carbonate (as CO3) mg/L ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5] ND [5]

Calcium mg/L 96 98 397 383 391 91 95 193 140 227 163 95 91

Magnesium mg/L 81 83 362 351 367 41 42 199 133 127 88 180 181

Potassium mg/L 22 19 24 23 24 20 20 18 13 24 27 31 32

Sodium mg/L 1210 1050 822 759 778 1450 1560 837 693 1190 1080 2420 2510

Chloride mg/L 39 37 14 15 13 20 16 17 15 49 53 136 144

Fluoride mg/L 4.0 0.7 0.7 0.6 0.6 0.5 0.5 0.4 0.7 0.5 0.3 0.3 0.8 0.7

Sodium Adsorption Ratio (SAR) 22.1 18.9 7.2 6.7 6.8 31.9 33.5 10.1 10 15.7 16.9 33.6 35

Sulfate mg/L 1420 1360 3160 3130 2970 1760 1680 2260 1830 2410 1830 3010 2920

Nutrients

Nitrogen, Nitrate-Nitrite (as N) mg/L 10.0 ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] ND [0.02] 0.04 ND [0.02] ND [0.02] ND [0.02]

Nitrogen, Ammonia (as N) mg/L 4.96 4.89 7.02 6.8 6.57 4.2 3.98 0.91 0.8 7.28 6.52 3.8 4.01

Dissolved Metals

Aluminum mg/L 0.0264J 0.013J 0.1 0.11 0.1 0.5 0.08 0.07 0.06 0.0285J 0.07 0.12 0.08

Arsenic mg/L 0.01 0.003 0.004 0.001 0.000898J 0.001 0.002 0.002 0.000799J 0.000601J 0.000562J 0.000833J 0.004 0.004

Boron mg/L 0.16 0.17 0.07 0.06 0.09 0.06 0.34 0.13 0.14 0.06 0.05 0.1 0.12

Cadmium mg/L 0.005 0.000145J 0.0008 0.000227J 0.000146J 0.0006 0.000185J 0.0006 0.000407J 0.0006 0.0006 0.0006 0.0008 0.0043

Copper mg/L 1.3 0.00133J ND [0.002] ND [0.002] ND [0.002] ND [0.002] 0.000523J ND [0.002] 0.000594J ND [0.002] 0.004 0.000774J ND [0.002] ND [0.002]

Iron mg/L 1.44 1.08 3.59 3.59 2.22 0.53 0.22 3.03 1.05 0.03 0.12 3.11 2.92

Lead mg/L 0.015 ND [0.0003] 0.00000642J ND [0.0003] ND [0.0003] 0.0000706J 0.000046J 0.000207J 0.000275J 0.0000366J 0.0005 0.000244J ND [0.0003] 0.0028

Manganese mg/L 0.178 0.125 0.292 0.294 0.326 0.108 0.082 0.55 0.312 0.091 0.066 0.711 0.69

Nickel mg/L 0.1 0.014 0.004 ND [0.002] ND [0.002] 0.007 ND [0.002] 0.003 ND [0.002] 0.004 ND [0.002] ND [0.002] 0.011 ND [0.002]

Selenium mg/L 0.05 ND [0.001] 0.000192J 0.000556J 0.000422J 0.000364J ND [0.001] 0.000224J 0.000307J 0.000273J 0.000857J 0.000539J ND [0.001] 0.001

Vanadium mg/L 0.00195J 0.00089J 0.00171J 0.00146J ND [0.01] 0.00264J 0.00124J 0.00137J 0.000139J 0.00143J 0.000312J 0.005J 0.000104J

Zinc mg/L 2.0 0.01 ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] ND [0.008] 0.00476J 0.413 ND [0.008]
APPENDIX D

SPRING CREEK MINE OBSERVED WILDLIFE SPECIES LIST

Spring Creek Mine TR1 EA D-1

SPRING CREEK MINE OBSERVED WILDLIFE SPECIES LIST 

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

MAMMALS

SHREWS

Sorex species

Once -- -- -- --

Sorex spp.

Merriam’s shrew1

Never -- -- -- --

Sorex merriami

Preble’s shrew1

Sorex preblei

Never -- -- -- --

BATS

Myotis species*

Regularly X2 X2 -- --

Myotis spp.

Big brown bat*

Regularly X X -- --

Eptesicus fuscus

Spotted bat1*

Occasionally X X -- --

Euderma maculatum

Eastern red bat1

Unknown -- -- -- --

Lasiurus borealis

Hoary bat1*

Regularly X X -- --

Lasiurus cinereus

Little brown myotis1*

Regularly X X -- --

Myotis lucifugus

Silver-haired bat*

Regularly X X -- --

Lasionycteris noctivagans

Western small-footed myotis*

Regularly X X -- --

Myotis ciliolabrum

Long-eared myotis*

Regularly X X -- --

Myotis evotis

Fringed myotis1*

Occasionally X X -- --

Myotis thysanodes

Townsend’s big-eared bat1

Unknown -- -- -- --

Corynorhinus townsendii

HARES AND RABBITS

Cottontail species*

Regularly X X X X

Sylvilagus spp.

White-tailed jackrabbit*

Occasionally -- -- -- X

Lepus townsendii

RODENTS & SQUIRRELS

Least chipmunk*

Often -- X X X

Tamias minimus

Yellow-bellied marmot*

Infrequently -- -- X X

Marmota flaviventris
D-2 Spring Creek Mine TR1 EA

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

Thirteen-lined ground squirrel

Occasionally -- -- -- --

Spermophilus tridecemlineatus

Black-tailed prairie dog1*

Regularly X X X

X

Cynomys ludovicianus

Northern pocket gopher4

Regularly X X -- X

Thomomys talpoides

Olive-backed pocket mouse

Rarely -- -- -- --

Perognathus fasciatus

Ord’s kangaroo rat*

Infrequently -- X -- X

Dipodomys ordii

Beaver3

Rarely -- -- -- --

Castor canadensis

Plains harvest mouse

Once5 -- -- -- --

Reithrodontomys montanus

Western harvest mouse

Rarely -- -- -- --

Reithrodontomys megalotis

Deer mouse*

Regularly X -- -- X

Peromyscus maniculatus

Northern grasshopper mouse

Infrequently -- -- -- --

Onychomys leucogaster

Bushy-tailed woodrat*

Occasionally -- X -- X

Neotoma cinerea

Prairie vole*

Occasionally X -- -- --

Microtus ochrogaster

Muskrat

Rarely -- -- -- --

Ondatra zibethicus

Porcupine

Regularly X X X --

Erethizon dorsatum

CARNIVORES

Coyote*

Regularly X X X X

Canis latrans

Red fox*

Infrequently X -- -- --

Vulpes vulpes

Raccoon3

Infrequently -- -- -- --

Procyon lotor

Mink

Once -- -- -- --

Mustela vison

Striped skunk

Rarely -- -- -- --

Mephitis

Badger*

Occasionally X X -- --

Taxidea taxus
Spring Creek Mine TR1 EA

D-3

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

Mountain lion*

OnceX -- -- --

Puma concolor

Bobcat*

Infrequently --X -- --

Lynx rufus

Black bear*

Rarely --X --X

Ursus americanus

UNGULATES

Mule deer*

RegularlyXXXX

Odocoileus hemionus

White-tailed deer

Frequently -- -- -- --

Odocoileus virginianus

Pronghorn*

RegularlyXXXX

Antilocapra americana

Elk*

Rarely -- -- -- --

Cervus canadensis

BIRDS

LOONS AND GREBES

Pied-billed grebe*

InfrequentlyX -- -- --

podilymbus podiceps

Eared grebe*

Rarely -- -- -- --

podiceps nigricollis

Western grebe*

Twice -- -- -- --

Aechmophorus occidentalis

PELICANS

American white pelican*

RarelyXX -- --

Pelecanus erythrothynchos

CORMORANTS

Double-crested cormorant*

OccasionallyXX -- --

Phalacrocorax auritus

BITTERNS, HERONS, AND 

IBISES

Great blue heron1*

RegularlyXXXX

Ardea herodias

GEESE AND DUCKS

Canada goose*

RegularlyXXXX

Branta canadensis

Green-winged teal*

Regularly -- -- --X

Anas crecca

Mallard*

RegularlyXXXX

Anas platyrhynchos

Northern pintail*

RarelyX -- -- --

Anas acuta
D

-4 Spring Creek Mine TR1 EA

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

Blue-winged teal*

OccasionallyX -- --X

Anas discors

Cinnamon teal*

Twice -- -- -- --

Anas cyanoptera

Northern shoveler*

RegularlyXX -- --

Anas clypeata

Gadwall*

RegularlyXX -- --

Anas strepera

American wigeon*

RegularlyXX --X

Anas americana

Redhead*

Infrequently -- -- -- --

Aythya americana

Ring-necked duck*

OccasionallyX -- -- --

Aythya collaris

Greater scaup*

Once -- -- -- --

Aythya marila

Lesser scaup*

InfrequentlyX -- -- --

Aythya affinis

Ruddy Duck*

OnceX -- -- --

Oxyura jamaicensis

Common goldeneye*

Twice -- -- -- --

Bucephala clangula

Bufflehead*

Rarely -- -- -- --

Bucephala albeola

Hooded merganser*

Twice -- -- -- --

Lophodytes cucullatus

Common merganser*

Rarely -- -- -- --

Mergus merganser

DIURNAL RAPTORS

Turkey vulture*

RegularlyXX --X

Cathartes aura

Osprey*

RegularlyXXXX

Pandion haliaetus

Bald eagle*

InfrequentlyXX -- --

Haliaeetus leucocephalus

Golden eagle1*

RegularlyXXXX

Aquila chrysaetos

Northern harrier*

RegularlyXXXX

Circus cyaneus

Sharp-shinned hawk*

Twice -- -- -- --

Accipiter striatus
Spring Creek Mine TR1 EA

D-5

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

Cooper’s hawk*

Infrequently -- --XX

Accipiter cooperii

Northern goshawk1*

Once -- -- -- --

Accipiter gentilis

Swainson’s hawk*

Rarely -- -- -- --

Buteo swainsoni

Red-tailed hawk*

RegularlyXXXX

Buteo jamaicensis

Ferruginous hawk*

Rarely -- -- --X

Buteo regalis

Rough-legged hawk*

Seasonally -- --XX

Buteo lagopus

American kestrel*

RegularlyXXXX

Falco sparverius

Merlin*

Once -- -- -- --

Falco columbarius

Prairie falcon*

FrequentlyXXXX

Falco mexicanus

Peregrine falcon1*

Rarely -- --X --

Falco peregrinus

COOTS AND RAILS

American coot*

OccasionallyXX --X

Fulica americana

Sora*

Once -- -- --X

Porzana carolina

Sandhill crane*

Infrequently -- -- -- --

Grus canadensis

GALLINACEOUS BIRDS

Gray partridge*

OccasionallyXX -- --

Perdix perdix

Ring-necked pheasant*

Infrequently -- -- -- --

Phasianus colchicus

Ruffed grouse*

Twice -- -- -- --

Bonasa umbellus

Greater sage-grouse1*

OccasionallyXX -- --

Centrocercus urophasianus

Sharp-tailed grouse*

RegularlyXXXX

Tympanuchus phasianellus

Wild turkey*

Meleagris gallopavo Occasionally -- -- --

X
D-6 Spring Creek Mine TR1 EA

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

SHOREBIRDS, AVOCETS, 

GULLS, AND TERNS

Killdeer*

Charadrius vociferus Regularly X X X X

Mountain plover

Charadrius montanus Never -- -- -- --

American avocet*

Retrocurvirostra americana Infrequently X -- -- --

Lesser yellowlegs*

Tringa flavipes Rarely -- -- -- --

Greater yellowleg*s

Tringa melanoleuca Rarely -- -- -- --

Solitary sandpiper*

Rarely -- -- -- --

Tringa solitaria

Willet*

Rarely -- -- -- --

Catoptrophorus semipalmatus

Spotted sandpiper*

Regularly X X X X

Actitis macularia

Upland sandpiper*

Regularly X -- X X

Bartramia longicauda

Western sandpiper*

Once -- -- -- X

Calidris mauri

Long-billed curlew1*

Numenius americanus Rarely -- X X X

Marbled godwit*

Limosa fedoa Once -- -- -- --

Wilson’s snipe*

Infrequently -- -- -- --

Gallinago delicata

Wilson’s phalarope*

Infrequently -- -- -- --

Phalaropus tricolor

Ring-billed gull*

Twice -- -- -- --

Larus delawarensis

Franklin’s Gull*

Once -- -- -- --

Larus pipixcan

PIGEONS AND DOVES

Rock pigeon*

Regularly X X X X

Columba livia

Mourning dove*

Regularly X X X X

Zenaida macroura

OWLS

Great horned owl*

Regularly X X X X

Bubo virginianus

Burrowing owl1*

Regularly X X -- X

Athene cunicularia
Spring Creek Mine TR1 EA

D-7

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

Short-eared owl*

Rarely -- -- --X

Asio flammeus

NIGHTJARS

Common nighthawk*

RegularlyXX --X

Chordeiles minor

Common poorwill*

Rarely -- -- -- --

Phalaenoptilus nuttallii

WOODPECKERS

Lewis’ woodpecker1*

Infrequently -- -- -- --

Melanerpes lewis

Red-headed woodpecker*

Infrequently -- -- -- --

Melanerpes erythrocephalus

Hairy woodpecker*

Infrequently -- -- -- --

Picoides villosus

Downy woodpecker*

Occasionally -- -- -- --

Picoides pubescens

Northern flicker*

RegularlyXXXX

Colaptes auratus

FLYCATCHERS

Western wood-pewee*

OccasionallyXXX --

Contopus sordidulus

Hammond’s flycatcher*

RarelyX -- -- --

Empidonax hammondii

Dusky flycatcher*

Once -- -- -- --

Empidonax oberholseri

Say’s phoebe*

RegularlyXXXX

Sayornis saya

Western kingbird*

RegularlyXXXX

Tyrannus verticalis

Eastern kingbird*

RegularlyXXXX

Tyrannus tryannus

Cassin’s kingbird*

Twice -- -- -- --

Tyrannus vociferans

LARKS

Horned lark*

RegularlyXXXX

Eremophila alpestris

SWALLOWS

Tree swallow*

Once -- -- -- --

Tachycineta bicolor

Violet-green swallow*

RegularlyXX -- --

Tachycineta thalassina
D-8 Spring Creek Mine TR1 EA

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

Cliff swallow*

Regularly X X X X

Hirundo pyrrhonota

Barn swallow*

Regularly X X X X

Hirundo rustica

Bank swallow*

Once -- -- -- --

Riparia riparia

BUNTINGS

Lazuli bunting*

Infrequently -- -- -- --

Passerina amoena

JAYS, CROWS, and MAGPIES

Gray jay*

Once -- -- -- --

Perisoreus canadensis

Pinyon jay1*

Occasionally X -- -- --

Gymnorhinus cyanocephalus

Scrub Jay*

Twice -- -- -- --

Aphelocoma coerulescens

Clark’s nutcracker1*

Rarely -- -- -- --

Nucifraga columbiana

Black-billed magpie*

Regularly X X X X

Pica hudsonia

American crow*

Regularly X X X X

Corvus brachyrhynchos

Common raven*

Occasionally X X X X

Corvus corax

CHICKADEES

Black-capped chickadee*

Regularly X X X X

Parus atricapillus

NUTHATCHES

Red-breasted nuthatch*

Occasionally -- -- -- --

Sitta canadensis

White-breasted nuthatch*

Occasionally -- -- X --

Sitta carolinensis

WRENS

Rock wren*

Regularly X X X X

Salpinctes obsoletus

House wren*

Often X -- -- --

Troglodytes aedon

Bewick’s wren

Once -- -- -- --

Thryomanes bewickii
Spring Creek Mine TR1 EA

D-9

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

CHATS

Yellow-breasted chat*

Regularly -- -- -- --

Icteria virens

LONGSPURS AND 

SNOW BUNTINGS

Chestnut-collared Longspur1

Calcarius ornatus Never -- -- -- --

KINGLETS, GNATCATCHERS, 

AND THRUSHES

Veery1

Catharus fuscescens Never -- -- -- --

Ruby-crowned kinglet*

Once -- -- -- --

Regulus calendula

Blue-gray gnatcatcher*

Once -- -- -- --

Polioptila nigriceps

Mountain bluebird*

RegularlyXXXX

Sialia currocoides

Townsend’s solitaire*

Occasionally --XX --

Myadestes townsendi

American robin*

RegularlyXXXX

Turdus migratorius

MIMIC THRUSHES

Sage thrasher1*

Rarely -- -- -- --

Oreoscoptes montanus

Brown thrasher*

TwiceXX --X

Toxostoma rufum

Gray Catbird*

Infrequently -- -- -- --

Dumetella carolinensis

PIPITS

American Pipit*

Once -- -- -- --

Anthus rubescens

Sprague’s Pipit

Never -- -- -- --

Anthus spragueii

SHRIKES

Loggerhead shrike1*

RegularlyXXXX

Lanius ludovicianus

STARLINGS

European starling*

Regularly --XXX

Strunus vulgaris

VIREOS

Plumbeous vireo*

RarelyX -- -- --

Vireo plumbeus
D-10 Spring Creek Mine TR1 EA

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

WARBLERS

Orange-crowned warbler*

Once -- -- -- --

Oreothlypis celata

Yellow warbler*

Regularly X X X X

Setophaga petechia

American redstart*

Infrequently -- -- X --

Setophaga ruticilla

Magnolia warbler*

Once -- -- -- --

Setophaga magnolia

Yellow-rumped warbler*

Regularly X X X --

Setophaga coronata

Black-and-white warbler*

Once -- -- -- --

Mniotilta varia

Common yellowthroat*

Once -- -- -- --

Geothlypis trichas

SPARROWS AND TOWHEES

Green-tailed towhee1*

Once -- -- -- --

Pipilo cholorurus

Spotted towhee*

Regularly X X X --

Pipilo maculatus

Chipping sparrow*

Regularly X X X X

Spizella passerina

Brewer’s sparrow1*

Regularly X X X X

Spizella breweri

Vesper sparrow*

Regularly X X X X

Ppooecetes gramineus

Lark sparrow*

Regularly X X X X

Chondestes grammacus

Lark bunting*

Regularly X X X X

Calamospiza melanocorys

Savannah sparrow*

Once -- -- -- --

Passerculus sandwichensis

Grasshopper sparrow*

Occasionally X -- X X

Ammodramus savannarum

Song sparrow*

Once -- -- -- --

Melospiza melodia

White-crowned sparrow*

Occasionally X X -- --

Zonotrichia leucophrys

Dark-eyed junco*

Occasionally -- -- -- X

Junco hyemalis
Spring Creek Mine TR1 EA

D-11

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

BLACKBIRDS, 

MEADOWLARKS, AND 

ORIOLES

Red-winged blackbird*

RegularlyXXXX

Agelaius phoneniceus

Western meadowlark*

RegularlyXXXX

Sturnella neglecta

Bobolink1

Dolichonyx oryzivorus Never -- -- -- --

Yellow-headed blackbird*

Infrequently -- -- -- --

Xanthocephalus xanthocephalus

Brewer’s blackbird*

RegularlyXXXX

Euphagus cyanocephalus

Common grackle*

Occasionally --XXX

Quiscalus quiscula

Brown-headed cowbird*

OccasionallyXXXX

Molothrus ater

Bullock’s oriole*

OccasionallyXX --X

Icterus bullockii

FINCHES

Red crossbill*

Infrequently -- --X --

Loxia curvirostra

Pine siskin*

Infrequently -- -- -- --

Carduelis pinus

American goldfinch*

OccasionallyXXXX

Carduelis tristis

Cassin’s finch1

Never -- -- -- --

Haemorhous cassinii

WEAVER FINCHES

House sparrow*

Twice -- -- -- --

Passer domesticus

CUCKOOS

Yellow-billed cuckoo1

Coccyzus americanus Never -- -- -- --

Black-billed cuckoo1

Coccyzus erythropthalmus Never -- -- -- --

AMPHIBIANS AND REPTILES

SALAMANDERS

Western tiger salamander*

Rarely -- -- -- --

Ambystoma mavortium
D-12 Spring Creek Mine TR1 EA

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

TRUE TOADS

Plains spadefoot*

Infrequently -- -- -- --

Spea bombifrons

Great Plains toad1*

Infrequently -- -- -- --

Bufo cognatus

Woodhouse’s toad*

Occasionally X X -- --

Bufo woodhousei

TREE FROGS

Boreal chorus frog*

Regularly X X X X

Pseudacris triseriata

TRUE FROGS

Northern leopard frog*

Occasionally -- -- X --

Rana pipiens

TURTLES

Painted turtle*

Occasionally -- -- -- X

Chrysemys picta

Snapping turtle1*

Rarely -- -- -- --

Chelydra serpentina

Spiny softshell1

Never -- -- -- --

Apalone spinifera

SPINY LIZARDS

Common sagebrush lizard*

Infrequently -- -- -- --

Sceloporus graciosus

Greater short-horned lizard1,3*

Rarely -- X -- --

Phrynosoma hernandesi

COLUBRID SNAKES

North American racer*

Twice -- -- -- --

Coluber constrictor

Plains hog-nosed snake1

Never -- -- -- --

Heterodon nasicus

Western milksnake1

Never -- -- -- --

Lampropeltis gentilis

Gophersnake (Bullsnake)*

Rarely X -- -- --

Pituophis melanoleucas

Common garter snake*

Rarely -- -- -- --

Thamnophis sirtalis

Wandering garter snake*

Occasionally -- -- -- --

Thamnophis elegans
Spring Creek Mine TR1 EA D-13

Historical 

Occurrence in 

Annual Monitoring 

Area (1994-2013)

2014-2015 2016 2017 2018

PIT VIPERS

Prairie rattlesnake*

Occasionally -- X X --

Crotalus viridis

FISH

Yellowstone Cutthroat Trout1

Oncorhynchus clarkii bouvieri Never -- -- -- --

Sauger1

Sander canadensis Never -- -- -- --

1 Animals on the Montana Natural Heritage Program Species of Concern List, updated September 25, 2018

2 Based on updated analysis of results from detection equipment previously located at SCM, per Montana Natural Heritage Program

3

Species name for the greater short-horned lizard was changed from douglassi to hernandesi in 2010 per MDEQ guidance from MNHP. 

4 Based on physical evidence (e.g., tracks, diggings, chewing marks, etc.)

5 Based on an examination of preserved specimens by Dr. Paul Hendricks (Montana Natural Heritage Program, Missoula, MT) the plains 

harvest mouse was retracted from the list of observed species for 2000. The occurrence of that species in 1995 is questionable.

* Observed in the SCM permit area.

Federally Listed Threatened and Endangered Species and Species with the 

potential to Occur in the Study Area (Determined Using USFWS IPaC System)

Species Status In Range 

(Yes/No)

Habitat Present 

(Yes/No)

Affects Determination (brief rationale)

Black-footed ferret

Mustela nigripes E/Exp* Yes Yes May affect, not likely to adversely affect. See discussion, section 4.10.4.1

* E/Exp: Endangered/Experimental population-Non-Essential, C: Candidate
APPENDIX E

CULTURAL RESOURCE MANAGEMENT 

INSIDE SMP C1979012

Spring Creek Mine TR1 EA E-1

Site ID from Plate 7 

SMP (Current NHRP 

Sites Bold & Shaded; 

Mitigated Bold only)

Pit Area

Planned 

Disturbance Date 

(estimated 1,200' 

offset from coal 

block)

Actual 

Disturbance 

Date

Additional 

Investigation 

Required

(Yes or No)

Mitigation 

Required** 

(Yes or 

No)

Summary of Mitigation Efforts

Mitigation 

(Year 

Planned or 

Completed)

2524 1 WEST 2013 2013 N N/A N/A N/A

2525 1 WEST N/A N/A N N/A N/A N/A

2526 1 WEST 2021 N N/A N/A N/A

2527 1 SOUTH N/A N/A N N/A N/A N/A

2532 1 WEST 2014 2014 N N/A N/A N/A

24BG3384 2 WEST 2016 2016 N N N/A N/A

24BG3385 2 EAST 2019 N N N/A N/A

24BG3386 2 EAST 2019 N N N/A N/A

24BG3393 2 EAST 2023 N N N/A N/A

24BG3397 2 EAST 2023 N N N/A N/A

24BH573 4 SOUTH 2019 N N N/A N/A

24BH1048 1 WEST N/A N/A N Y Completed in 1992 by GCM N/A

24BH1059 4 SOUTH 2026 N N N/A N/A

24BH1068 1 EAST Future N/A N N Within Future LBA II Area N/A

24BH1583 2 WEST N/A N/A N N/A N/A N/A

24BH1589 2 WEST 2019 N Y Mitigated; authorized disturb 2‐24‐

15

2013

24BH1591 2 SOUTH 2023 Y N

DNRC Requested testing in '18. Tested, 

not significant. DNRC ltr 6‐6‐18 not an 

eligible site. 2018

24BH1593 2 SOUTH 2021 N N/A

2010 SHPO Not eligible; Recorded as 

3407 & 3409 by GCM N/A

24BH1598 4 WEST 2019 2018 N Y Mitigated; authorized disturb 10‐16‐

17

2018

24BH1599 4 SOUTH 2019 N N N/A N/A

24BH1600 4 SOUTH 2012 2013 N N N/A N/A

24BH1614 RR Corr N/A N/A N N/A N/A N/A

24BH1619 1 WEST N/A N/A N N/A N/A N/A

24BH1734 4 NORTH N/A N/A N N/A N/A N/A

24BH1735 4 NORTH N/A N/A N N NW of Rock Art, Will Not be 

Disturbed

N/A

24BH1736 4 NORTH N/A N/A N N

Boundary Rev. 3‐13‐17 SHPO 

Approved.

Revised site boundary will not be 

disturbed.

2017

24BH1737 4 NORTH 2016 2016 N Y Completed SHPO Approved 7‐30‐

16

2012‐13

24BH1738 4 NORTH 2019 N N/A N/A N/A

24BH1739 4 NORTH 2019 N Y

Field Mitigation Complete, 

authorized to disturb 1‐23‐19 2018

24BH1740 4 NORTH 2019 N N/A No Longer Eligible by SHPO 3‐13‐17 N/A

24BH1741 4 NORTH N/A N/A N N/A N/A N/A

24BH1742 4 NORTH 2018 2018 N N N/A N/A

24BH1743 4 NORTH 2018 2018 N N N/A N/A

24BH1744 4 NORTH 2016 2016 N N N/A N/A

24BH1745 4 NORTH 2012 2013 N N N/A N/A

24BH1747 4 NORTH N/A N/A N N/A N/A N/A

24BH1748 4 NORTH 2019 N Y

Field Mitigation Complete, 

authorized to disturb 10‐27‐18 2016

24BH1749 4 NORTH 2016 2016 N N N/A N/A

24BH2003 2 EAST N/A N/A N N/A N/A N/A

24BH2008 6 EAST N/A N/A N N/A N/A N/A

24BH2010 6 EAST N/A N/A N N/A N/A N/A

24BH2253 4 SOUTH N/A N/A N N/A N/A N/A

24BH2254 4 SOUTH 2014 2014 N Y Completed in 2002 by GCM 2002

24BH2255 4 NORTH N/A N/A N N/A N/A N/A

24BH2317 TRR 2015 2015 Y N DNRC & SHPO Approval 3‐16‐15 2015

24BH2318 4 SOUTH N/A N/A N N/A N/A N/A

24BH2319 4 SOUTH N/A N/A N N/A N/A N/A

24BH2320 4 SOUTH 2015 2015 N N N/A N/A

24BH2516 1 WEST N/A N/A N Y

W of Pit #1: Annual Photos on going, will not 

be disturbed N/A

24BH2521 1 WEST N/A N/A N Y Completed in 1992 by GCM N/A

24BH2529 1 WEST N/A N/A N Y Completed in 1992 by GCM N/A

24BH2530 1 EAST 2025 N N Additional Field Testing '15, rpt. to BLM N/A

24BH2531 1 EAST 2014 2014 N N Additional Field Testing '15, rpt. to BLM N/A

24BH2533 1 EAST 2025 N N N/A N/A

24BH2534 1 EAST 2025 N N N/A N/A

24BH2841 4 NORTH N/A N/A N N/A N/A N/A
E-2 Spring Creek Mine TR1 EA

Site ID from Plate 7 

SMP (Current NHRP 

Sites Bold & Shaded; 

Mitigated Bold only)

Pit Area

Planned 

Disturbance Date 

(estimated 1,200' 

offset from coal 

block)

Actual 

Disturbance 

Date

Additional 

Investigation 

Required

(Yes or No)

Mitigation 

Required** 

(Yes or 

No)

Summary of Mitigation Efforts

Mitigation 

(Year 

Planned or 

Completed)

24BH2842 4 NORTH N/A N/A N N/A N/A N/A

24BH2869 4 WEST N/A N/A N N/A N/A N/A

24BH3079 2 EAST N/A N/A N N/A N/A N/A

* Mitigation includes only data recovery; see Permit Volume 1 Section 303 ‐ Addendum 303R‐ Appendix D; mitigation completed in 2012 and 2013.

** Sites require mitigation efforts as required by a lease commitment or as required in Appendix G‐G4 of the baseline investigation. All sites in italics will 

be disturbed with the approval of mining the TR1 Major permit revision or future leases; disturbance not currently permitted