U.S. Department of the Interior Bureau of Land Management Wyo-Ben, Inc. – 52G Plan of Operations Modification for Bentonite Mining (WYW-151001) DOI-BLM-WY-R020-2018-0012-EA BLM/WY/PL-18/010+1330 June 2018 Table of Contents Table of Contents ...................................................................................................................................................................................................................... 2 1.0 INTRODUCTION ...................................................................................................................................................................................................................... 3 1.1 Background .......................................................................................................................................................................................................................... 3 1.2 Purpose and Need ............................................................................................................................................................................................................. 3 1.3 Issues Identified During Scoping ............................................................................................................................................................................... 3 1.4 Relationship to Statutes, Regulations, Policies, Plans or Other Environmental Analyses ............................................................. 4 2.0 PROPOSED ACTION AND ALTERNATIVES ................................................................................................................................................................ 4 2.1 Alternative I – No Action ............................................................................................................................................................................................... 4 2.2. Alternative II – Proposed Action............................................................................................................................................................................... 6 3.0 AFFECTED ENVIRONMENT and ENVIRONMENTAL EFFECTS ..................................................................................................................... 10 3.1 Affected Environment/Environmental Effects (Direct & Indirect Impacts) ..................................................................................... 10 3.1.1 Air Quality ................................................................................................................................................................................................................. 10 3.1.2 Cultural Resources and Native American Religious Concerns ........................................................................................................ 10 3.1.3 Water (Surface and Ground), Riparian Areas, and Wetlands .......................................................................................................... 11 3.1.4 Geology and Minerals .......................................................................................................................................................................................... 12 3.1.5 Paleontological Resources ................................................................................................................................................................................ 13 3.1.6 Soils .............................................................................................................................................................................................................................. 13 3.1.8 Invasive, Non-native Plant Species ............................................................................................................................................................... 16 3.1.9 Wildlife ....................................................................................................................................................................................................................... 17 3.1.10 Livestock Grazing and Range Management ........................................................................................................................................... 19 3.1.11 Socioeconomics ................................................................................................................................................................................................... 19 3.1.12 Recreation and Visual Resource Management (VRM) ...................................................................................................................... 20 3.2 Mitigation and Monitoring ......................................................................................................................................................................................... 21 3.3 Stipulations ....................................................................................................................................................................................................................... 22 3.4 Cumulative Impacts ...................................................................................................................................................................................................... 24 3.4.1 Past, Present, Reasonably Foreseeable Future Actions, and Incremental Effects ................................................................. 24 3.4.2 Residual Impacts.................................................................................................................................................................................................... 26 4.0 List of Preparers: ................................................................................................................................................................................................................. 27 5.0 List of Reviewers ................................................................................................................................................................................................................. 27 6.0 Consultation ........................................................................................................................................................................................................................... 27 7.0 References .............................................................................................................................................................................................................................. 29 Appendix A – Climate ................................................................................................................................................................................................................ 31 Appendix B – BLM seed policy in IM-2006-073 ........................................................................................................................................................... 32 Appendix C – Castback Mining Sequence ........................................................................................................................................................................ 34 Appendix D – Wyoming State-listed Noxious Weeds ................................................................................................................................................ 35 Figure 1. Map of Wyo-Ben’s 52G Plan of Operations Modification area ........................................................................................................... 5 Figure 2. Map of Wyo-Ben’s 52G Plan of Operations Modification area ........................................................................................................... 7 Figure 4. Map of Minerals and Grazing Cumulative Effects Analysis Area for the 52G Modification. .............................................. 28 Figure 4. Schematic of a castback mining sequence ................................................................................................................................................. 34 Table 1. Seed Mix for the 52G Modification. ................................................................................................................................................................... 9 Table 2. Soil Types and Range Sites of the 52G Modification ............................................................................................................................... 13 Table 3. Vegetation Community Types in the 52G Modification Area. ............................................................................................................ 15 Table 4. Period of Record Monthly Climate Summary for Lovell, Wyoming (April 1, 1897 to May 31, 2016) ............................ 31 2 1.0 INTRODUCTION 1.1 Background The bentonite mining company Wyo-Ben, Inc, (Wyo-Ben) has submitted to the Bureau of Land Management (BLM) the 52G Plan of Operations Modification (WYW-151001) seeking approval to mine seven miles northwest of Greybull, Wyoming (see Figure 1). This Plan Modification proposes to add a total of 3.9 acres of surface disturbance to their existing Wyoming Department of Environmental Quality – Land Quality Division (WDEQ-LQD) Permit 321C located in Big Horn County, Wyoming, over the life of the operation. Of the 3.9 acres of proposed