United States Department of FINAL Environmental Agriculture Assessment for the Thunder Basin Coal Company, LLC. Forest Service August2012 Black Thunder Coal Mine Dewatering & Overstripping Project Douglas Ranger District, Medicine Bow-Routt National Forests and Thunder Basin National Grassland Campbell County, Wyoming, 6th Principal Meridian Township 43 North, Range 71 West, Section 23, 26, and 35; Township 43 North, Range 71 West, Section 10; and Township 42 North, Range 71 West, Sections 1 and 2 Responsible Official – Phil Cruz, Forest Supervisor For Further Information Contact: Amy Ormseth, P.E. Minerals & Lands Program Manager Douglas Ranger District Medicine Bow/Routt NFs & Thunder Basin NG 2250 E. Richards St. Douglas, WY 82633 (307) 358-4690 (phone) (307) 358-7107 (FAX) [email protected] TABLE OF CONTENTS Summary ............................................................................................................................... 1 Acronyms .............................................................................................................................. 4 Document Structure............................................................................................................... 6 Chapter 1 Purpose of and Need for Action .............................................................................. 7 Geographic Area Direction ............................................................................................................................. 7 Hilight Bill Geographic Area ................................................................................................................................. 7 Desired Conditions .......................................................................................................................................... 7 Management Area Direction ........................................................................................................................... 7 Management Area 8.4 – Mineral Production and Development ......................................................................... 8 Desired Conditions .......................................................................................................................................... 8 Purpose of and Need for Action ...................................................................................................................... 8 Proposed Action ............................................................................................................................................ 11 Decision Framework ..................................................................................................................................... 12 Authorities and Regulations .......................................................................................................................... 12 Public Involvement ....................................................................................................................................... 13 Issues ............................................................................................................................................................. 15 Chapter 2: Alternatives, Including the Proposed Action ........................................................ 17 Alternatives Considered in Detail ................................................................................................................. 17 Monitoring ......................................................................................................................................................... 19 Comparison of Alternatives ........................................................................................................................... 20 Chapter 3 Affected Environment and Environmental Consequences ...................................... 21 Affected Environment ................................................................................................................................... 21 3.1 Heritage - Cultural Resources ....................................................................................................................... 27 Existing Conditions ........................................................................................................................................ 27 Environmental Consequences (Effects Analysis) ........................................................................................... 29 3.2 Paleontological Resources ........................................................................................................................... 30 Existing Conditions ........................................................................................................................................ 30 Environmental Consequences (Effects Analysis) ........................................................................................... 32 3.3 Air Quality .................................................................................................................................................... 33 3.4 Wildlife Resources ........................................................................................................................................ 49 3.4.1 Federally Listed Threatened, Endangered, and Candidate Vertebrate Species ................................... 51 Existing Conditions ........................................................................................................................................ 51 Black-footed Ferret ....................................................................................................................................... 52 Environmental Consequences (Effects Analysis) ........................................................................................... 53 3.4.2 USFS Region 2 - Sensitive Species ......................................................................................................... 54 Existing Conditions ........................................................................................................................................ 54 Environmental Consequences (Effects Analysis) ........................................................................................... 58 3.4.3 Management Indicator Species (MIS) .................................................................................................. 62 Existing Conditions ........................................................................................................................................ 62 Habitat ........................................................................................................................................................... 64 Populations .................................................................................................................................................... 65 Alternative 1: No Action .............................................................................................................................. 71 Grassland Plan Compliance ........................................................................................................................... 72 Alternative 2: Proposed Action ..................................................................................................................... 72 Cumulative Effects ........................................................................................................................................ 74 Grassland Plan Compliance ........................................................................................................................... 76 3.5 Vegetation Resources .................................................................................................................................. 77 Field Reconnaissance .................................................................................................................................... 80 3.5.3 Threatened, Endangered, and Proposed Plant Species Considered and Evaluated............................. 81 TBCC Dewatering & Overstripping Environmental Assessment i TABLE OF CONTENTS Environmental Consequences (Effects Analysis) ........................................................................................... 81 Existing Conditions ........................................................................................................................................ 84 Environmental Consequences (Effects Analysis) ........................................................................................... 85 3.6 Soils .............................................................................................................................................................. 87 Methods ........................................................................................................................................................ 87 Existing Conditions ........................................................................................................................................ 88 Environmental Consequences (Effects Analysis) ........................................................................................... 88 3.7 Hydrology ..................................................................................................................................................... 91 Environmental Consequences ......................................................................................................................