BLM U.S. Department of the Interior Bureau of Land Management Office/Montana Field Billings Pryor Mountain Travel Management Area Draft Travel Management Plan Environmental Assessment DOI-BLM-MT-C010-2019-0029-EA October 2019 Prepared by: U.S. Bureau of Land Management Billings Field Office 5001 Southgate Drive Billings, MT 59101 Phone: 406-896-5013 Fax: 406-896-5281 It is the mission of the Bureau of Land Management to sustain the health, diversity, and productivity of the public lands for the use and enjoyment of present and future generations. DOI-BLM-MT-C010-2019-0029-EA Table of Contents 1.0 Purpose and Need for Action ........................................................................................................ 1-1 1.1 Background ...................................................................................................................... 1-1 1.2 Purpose and Need ............................................................................................................ 1-1 1.3 Decision to be Made ........................................................................................................ 1-2 1.4 Conformance with Land Use Plan ................................................................................... 1-2 1.5 Relationship to Statutes, Regulations, Policies, and Other NEPA Documents ................ 1-2 1.6 Public Involvement, Consultation, and Coordination ...................................................... 1-2 1.7 Resource Issues Identified for Analysis ........................................................................... 1-3 1.8 Resource Issues Considered but Eliminated from Further Analysis ................................ 1-4 1.9 Resource Issues Carried Forward for Further Analysis ................................................... 1-4 2.0 Proposed Action and Alternatives................................................................................................. 2-1 2.1 Introduction ...................................................................................................................... 2-1 2.2 Route Designations .......................................................................................................... 2-1 2.3 Alternatives Considered but Eliminated from Further Consideration .............................. 2-3 2.3.1 Revised Statute 2477 ........................................................................................ 2-3 2.4 No Action Alternative ...................................................................................................... 2-4 2.5 Proposed Action (Alternative D) ..................................................................................... 2-6 2.5.1 Minor Realignments ......................................................................................... 2-8 2.5.2 Route Closures ................................................................................................. 2-8 2.5.3 Authorizations .................................................................................................. 2-9 2.5.4 Cultural Resources ........................................................................................... 2-9 2.5.5 Future Improvements ..................................................................................... 2-10 2.6 Summary Comparison of Alternatives ........................................................................... 2-10 3.0 Affected Environment and Environmental Consequences ........................................................... 3-1 3.1 Soils ................................................................................................................................. 3-1 3.1.1 Affected Environment ...................................................................................... 3-1 3.1.2 Environmental Consequences .......................................................................... 3-5 3.2 Wildlife (Bighorn Sheep and Greater Sage-Grouse) ....................................................... 3-8 3.2.1 Affected Environment ...................................................................................... 3-8 3.2.2 Environmental Consequences .......................................................................... 3-9 3.3 Cultural Resources ......................................................................................................... 3-11 3.3.1 Affected Environment .................................................................................... 3-11 3.3.2 Environmental Consequences ........................................................................ 3-14 3.4 Areas with Special Designations ................................................................................... 3-16 3.4.1 Affected Environment .................................................................................... 3-16 3.4.2 Environmental Consequences ........................................................................ 3-18 3.5 Transportation and Access ............................................................................................. 3-20 3.5.1 Affected Environment .................................................................................... 3-20 3.5.2 Environmental Consequences ........................................................................ 3-21 Draft Pryor Mountain TMA Environmental Assessment October 2019 i 3.6 Recreation and Visitor Services ..................................................................................... 3-22 3.6.1 Affected Environment .................................................................................... 3-22 3.6.2 Environmental Consequences ........................................................................ 3-23 3.7 Wilderness Characteristics ............................................................................................. 3-24 3.7.1 Affected Environment .................................................................................... 3-24 3.7.2 Environmental Consequences ........................................................................ 3-27 3.8 Invasive, Non-native Species ......................................................................................... 3-29 3.8.1 Affected Environment .................................................................................... 3-29 3.8.2 Environmental Consequences ........................................................................ 3-29 4.0 Cumulative Effects Analysis ......................................................................................................... 4-1 4.1 Cumulative Projects ......................................................................................................... 4-1 4.2 Soils ................................................................................................................................. 4-1 4.3 Wildlife (Bighorn Sheep and Greater Sage-Grouse) ....................................................... 4-1 4.4 Cultural Resources ........................................................................................................... 4-2 4.5 Transportation and Access ............................................................................................... 4-2 4.6 Recreation and Visitor Services ....................................................................................... 4-2 4.7 Invasive, Non-native Species ........................................................................................... 4-2 5.0 List of Preparers ............................................................................................................................ 5-1 Draft Pryor Mountain TMA Environmental Assessment October 2019 ii List of Tables Table 1-1. Key Issues and Indicators Developed for the Proposed Action ........................................... 1-5 Table 1-2. Resources Considered but Eliminated from Analysis .......................................................... 1-7 Table 1-3. Resources Carried Forward for Analysis ............................................................................. 1-9 Table 2-1. Alternatives Considered but Eliminated from Further Consideration.................................. 2-3 Table 2-2. Miles and Percentages of Route Designations under the No Action Alternative ................. 2-4 Table 2-3. Miles and Percentages of Route Designations under Proposed Action ............................... 2-8 Table 2-4. Resource Issues and Indicators under the No Action and Proposed Action Alternatives . 2-10 Table 3-1. Water and Wild Erosion Potential on BLM-Administered Land within the TMA .............. 3-5 Table 3-2. Route Miles through Areas of High and Moderate Wind Erosion Potential – No Action ... 3-6 Table 3-3. Route Miles through Areas of High and Moderate Water Erosion Potential – No Action 3-6 Table 3-4. Route Miles through Areas of High and Moderate Wind Erosion Potential – Proposed Action .................................................................................................................................. 3-7 Table 3-5. Route Miles through Areas of High and Moderate Water Erosion Potential – Proposed Action .................................................................................................................................. 3-7 Table 3-6. Rocky Mountain Bighorn Sheep Habitat within the TMA .................................................. 3-8 Table 3-7. Greater Sage-Grouse Habitat within the TMA ...................................................................