UNITED STATES DEPARTMENT OF THE INTERIOR OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT Bull Mountains Mine No. 1 Federal Mining Plan Modification Environmental Assessment Musselshell County and Yellowstone County, Montana Federal Coal Lease MTM 97988 March 13, 2018 U.S. Department of the Interior Office of Surface Mining Reclamation and Enforcement Western Region 1999 Broadway, Suite 3320 Denver, CO 80202 PH: 303-293-5000 FAX: 303-293-5032 Table of Contents TABLE OF CONTENTS 1.0 PURPOSE AND NEED ........................................................................................... 1 1.1 Introduction ...................................................................................................................................... 1 1.2 Regulatory Framework and Necessary Authorizations .......................................................... 4 1.3 Purpose and Need ........................................................................................................................... 4 1.4 Issues Identification .......................................................................................................................... 5 1.5 Crosswalk of Resource Areas ....................................................................................................... 6 1.6 Consultation and Coordination ......................................................................................................... 7 2.0 PROPOSED ACTION AND ALTERNATIVES .................................................... 8 2.1 Existing Condition ............................................................................................................................ 8 2.1.1 Mining Plan and Mining Operations..................................................................................... 9 2.1.2 Surface Facilities Area ............................................................................................................ 9 2.1.3 Other Surface Facilities ....................................................................................................... 10 2.1.4 Subsidence and Associated Surface Repairs ................................................................... 12 2.1.5 Hydrological Impacts and Mitigation ................................................................................ 13 2.1.6 Mining-Related Stipulations and Mitigation Measures .................................................. 14 2.1.7 Coal Loadout ........................................................................................................................ 14 2.1.8 Coal Destinations ................................................................................................................. 14 2.2 Description of Alternatives ......................................................................................................... 15 2.2.1 No Action Alternative ........................................................................................................ 16 2.2.2 Proposed Action .................................................................................................................. 18 2.3 Alternatives Eliminated from Detailed Study .......................................................................... 19 2.3.1 Subsurface Gas Control ...................................................................................................... 19 2.3.2 Avoidance of Impacts to Surface Resources, Features, and Uses ............................. 20 2.3.3 Alternative Land Uses ......................................................................................................... 20 3.0 AFFECTED ENVIRONMENT .............................................................................. 21 3.1 Transportation & Electrical Transmission ............................................................................... 21 3.1.1 Vehicle Transportation ....................................................................................................... 21 3.1.2 Electrical Transmission ....................................................................................................... 22 3.1.3 Rail Transportation .............................................................................................................. 22 3.2 Air Quality ...................................................................................................................................... 25 3.2.1 Mining ...................................................................................................................................... 25 3.2.2 Rail Transport ....................................................................................................................... 26 3.2.3 Seaport Handling .................................................................................................................. 26 3.2.4 Ocean Transport .................................................................................................................. 27 3.2.5 Overseas Combustion ........................................................................................................ 27 3.3 Climate ............................................................................................................................................ 27 3.3.1 Background ............................................................................................................................ 28 3.3.2 GHG Emissions ..................................................................................................................... 28 3.3.3 Climate Change .................................................................................................................... 30 3.3.4 Applicable Regulations and Policies.................................................................................. 30 3.4 Water Resources .......................................................................................................................... 31 3.4.1 Groundwater ............................................................................................................................... 32 3.4.2 Springs ..................................................................................................................................... 32 3.4.3 Surface Water ....................................................................................................................... 33 3.4.4 Hydrologic Conditions Surrounding the Existing WDA ............................................. 33 3.4.5 Waters of the U.S., including Wetlands .......................................................................... 33 3.4.6 Spring and Well Impact Mitigation .......................................................................................... 34 3.5 Soil .................................................................................................................................................... 34 3.6 Vegetation ....................................................................................................................................... 34 3.7 Wildlife ............................................................................................................................................ 35 3.8 Threatened, Endangered, and Special Status Species ............................................................ 36 3.9 Cultural and Paleontological Resources .................................................................................. 38 Bull Mountains Mine No. 1 Federal Mining Plan Modification EA i Table of Contents 3.10 Noise & Vibration ..................................................................................................................... 39 3.10.1 Mine Vicinity .......................................................................................................................... 39 3.10.2 Rail Transport Corridor ..................................................................................................... 39 3.11 Socioeconomics ............................................................................................................................. 40 3.11.1 Local Economy .......................................................................................................................... 40 3.11.2 Population. ................................................................................................................................. 41 3.11.3 Employment ........................................................................................................................... 41 3.11.4 Housing ................................................................................................................................... 42 3.11.5 Local Government Facilities and Services ...................................................................... 42 3.12 Environmental Justice ................................................................................................................... 42 3.13 Visual Resources ........................................................................................................................... 43 4.0 ENVIRONMENTAL CONSEQUENCES ............................................................ 44 4.1 Transportation & Transmission ...................................................................................................... 46 4.1.1 Direct & Indirect Effects ..................................................................................................... 46 4.1.2 Cumulative