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, Montana Federal Coal Lease MTM 97988 October 2014 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 TABLE OF CONTENTS TABLE OF CONTENTS 1.0 Introduction ................................................................................................................................................... 1-1 1.1 Regulatory Framework and Necessary Authorizations ..................................................................... 1-5 1.2 Purpose and Need....................................................................................................................................... 1-6 1.3 Issues Identification ..................................................................................................................................... 1-7 1.4 Crosswalk of Resource Areas .................................................................................................................. 1-7 2.0 Proposed Action & Alternatives.......................................................................................................... 2-1 2.1 Existing Condition ....................................................................................................................................... 2-1 2.1.1 Mining Plan and Mining Operations ............................................................................................... 2-1 2.1.2 Surface Facilities Area ....................................................................................................................... 2-2 2.1.3 Other Surface Facilities .................................................................................................................... 2-2 2.1.4 Subsidence and Associated Surface Repairs ................................................................................ 2-7 2.1.5 Stipulations and Mitigation Measures ............................................................................................ 2-8 2.2 Description of Alternatives ....................................................................................................................... 2-8 2.2.1 No Action Alternative ...................................................................................................................... 2-8 2.2.2 Proposed Action Alternative .......................................................................................................... 2-9 2.2.3 Alternatives Considered but Eliminated .................................................................................... 2-11 3.0 Affected Environment .............................................................................................................................. 3-1 3.1 Air Quality .................................................................................................................................................... 3-1 3.1.1 Air Quality-Particulate Matter ........................................................................................................ 3-1 3.1.2 Greenhouse Gases/Climate Change ..................................................................................................... 3-5 3.2 Water Resources ........................................................................................................................................ 3-8 3.2.2 Springs ................................................................................................................................................ 3-13 3.2.3 Hydrologic Conditions Surrounding the Existing WDA ........................................................ 3-16 3.2.4 Waters of the U.S., including Wetlands ..................................................................................... 3-17 3.3 Soil................................................................................................................................................................. 3-17 3.4 Vegetation ................................................................................................................................................... 3-19 3.5 Wildlife ......................................................................................................................................................... 3-19 3.6 Threatened, Endangered, and Special Status Species ........................................................................ 3-20 3.7 Cultural Resources ................................................................................................................................... 3-20 3.8 Noise ............................................................................................................................................................ 3-21 4.0 Environmental Consequences .............................................................................................................. 4-1 4.1 Effects from Proposed Action Alternative ............................................................................................ 4-1 4.1.1 Topography and Physiography........................................................................................................ 4-1 4.1.2 Geology, Mineral Resources, and Paleontology ......................................................................... 4-2 4.1.3 Air Quality ........................................................................................................................................... 4-2 4.1.4 Water Resources............................................................................................................................... 4-4 4.1.5 Soil ....................................................................................................................................................... 4-15 4.1.6 Vegetation ......................................................................................................................................... 4-15 4.1.7 Wildlife ............................................................................................................................................... 4-16 4.1.8 Threatened, Endangered, and Special Status Species .............................................................. 4-18 4.1.9 Ownership and Use of Land ......................................................................................................... 4-18 4.1.10 Cultural Resources .......................................................................................................................... 4-18 4.1.11 Visual Resources .............................................................................................................................. 4-19 4.1.12 Noise .................................................................................................................................................. 4-19 4.1.13 Transportation Facilities ................................................................................................................ 4-20 4.1.14 Hazardous and Solid Waste .......................................................................................................... 4-20 4.1.15 Short-term Uses and Long-term Productivity .......................................................................... 4-21 4.1.16 Unavoidable Adverse Effects ......................................................................................................... 4-21 4.1.17 Irreversible and Irretrievable Commitments of Resources................................................... 4-21 Bull Mountains Mine No. 1 Federal Mining Plan Modification EA i TABLE OF CONTENTS 4.2 Effects from No Action ............................................................................................................................ 4-23 4.2.1 Topography and Physiography...................................................................................................... 4-23 4.2.2 Geology, Mineral Resources, and Paleontology ....................................................................... 4-23 4.2.3 Air Quality ......................................................................................................................................... 4-23 4.2.4 Water Resources............................................................................................................................. 4-24 4.2.5 Soil ....................................................................................................................................................... 4-24 4.2.6 Vegetation ......................................................................................................................................... 4-24 4.2.7 Wildlife ............................................................................................................................................... 4-25 4.2.8 Threatened, Endangered, and Special Status Species .............................................................. 4-25 4.2.9 Ownership and Use of Land ......................................................................................................... 4-25 4.2.10 Cultural Resources .......................................................................................................................... 4-25 4.2.11 Visual Resources .............................................................................................................................