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United States Department of the Interior Bureau of Land Management Colorad o River District, Arizona District, o River United States Department of the Interior Bureau of Land Management Environmental Assessment DOI-BLM-AZ-C020-2018-0002-EA Bonanza Explorations, Inc. Copperstone Mine U.S. Department of the Interior Bureau of Land Management Colorado River District Yuma Field Office 7341 E 30th St (928) 317-3200 November, 2019 Table of Contents 1 Introduction ........................................................................................................................... 5 Identifying Information .................................................................................................... 5 1.1.1 Title, Environmental Assessment Number, Type of Project .................................... 5 1.1.2 Applicant Name ........................................................................................................ 5 1.1.3 Location of Proposed Action .................................................................................... 5 Introduction and Background ........................................................................................... 7 Purpose and Need for the Proposed Action ..................................................................... 7 Decision to be Made ......................................................................................................... 7 Conformance, Permits, and Approvals ............................................................................ 8 1.5.1 Conformance with BLM Land Use Plan(s) .............................................................. 8 1.5.2 Permits ...................................................................................................................... 9 1.5.3 Relationship to Statutes, Regulations, or Other Plans ............................................ 10 Scoping and Issue Identification .................................................................................... 11 1.6.1 Summary of Public Participation ............................................................................ 11 1.6.2 Issues Identified ...................................................................................................... 11 2 Description of Alternatives................................................................................................. 12 Introduction .................................................................................................................... 12 Proposed Action ............................................................................................................. 12 2.2.1 Applicant Committed Environmental Protection Measures ................................... 15 No Action Alternative .................................................................................................... 16 Alternative Considered but Eliminated from Further Analysis ..................................... 16 3 Affected Environment and Environmental Consequences ............................................. 17 Introduction .................................................................................................................... 17 General Setting ............................................................................................................... 17 Elements/Resources of the Human Environment........................................................... 17 Resources/Issues Brought Forward for Analysis ........................................................... 20 3.4.1 Air Quality .............................................................................................................. 20 3.4.2 Human Health and Safety ....................................................................................... 22 3.4.3 Wastes (hazardous/solid) ........................................................................................ 22 3.4.4 Native American Religious Concerns ..................................................................... 23 3.4.5 Threatened, Endangered, Candidate, or Sensitive Animal Species ........................ 24 3.4.6 Cultural Resources .................................................................................................. 28 3.4.7 Water Quality (drinking/ground) ............................................................................ 28 3.4.8 Vegetation (native and invasive) ............................................................................ 30 3.4.9 Wildlife ................................................................................................................... 31 3.4.10 Mineral Resources .................................................................................................. 33 3.4.11 Socio-economic Values .......................................................................................... 33 4 Cumulative Effects .............................................................................................................. 36 Introduction .................................................................................................................... 36 Cumulative Impacts........................................................................................................ 36 4.2.1 Description of Past, Present, and Reasonably Foreseeable Future Actions ............ 36 4.2.2 Past and Present Actions ......................................................................................... 36 4.2.3 Reasonably Foreseeable Future Actions ................................................................. 37 Cumulative Impacts of the Proposed Action.................................................................. 38 2 Cumulative Impacts of the No Action Alternative......................................................... 39 5 Consultation and Coordination ......................................................................................... 40 List of Preparers ............................................................................................................. 40 6 References ............................................................................................................................ 41 Appendix A: Copperstone Mine Plan of Operations Figures Figure 1-1: General Location Map Figure 2-2: Copperstone Detailed Mine Map Tables Table 1-5: Current Copperstone Mine Permits Table 3-1: Elements/Resources of the Human Environment Table 5-1: BLM Preparers Table 5-2: Third-Party Contractors Table 5-3: Kerr Mines List of Acronyms and Abbreviations ADEQ Arizona Department of Environmental Quality ADWR Arizona Department of Water Rights APE Area of Potential Effect APP Aquifer Protection Permit APS Arizona Public Service Company ARMP Amended Resource Management Plan ATF Alcohol, Tobacco, and Firearms BBCS Bird Bat Conservation Strategy BLM Bureau of Land Management CFR Code of Federal Regulation CIC Carbon-in-column CO Carbon Dioxide CRF Cemented Rock Fill CRIT Colorado River Indian Tribes DOT Department of Transportation EA Environmental Assessment EIS Environmental Impact Statement EPA United States Environmental Protection Agency ERM Environmental Resources Management FLPMA Federal Land Policy and Management Act of 1976 HAPs Hazardous Air Pollutants HCN Hydrogen Cyanide HIV Human Immunodeficiency Virus ID Team Interdisciplinary Team ICMI International Cyanide Management Institute MCL maximum contaminant level 3 mg/L milligrams per Liter MPO Mining Plan of Operations MT Million tons NAAQS National Ambient Air Quality Standards NEPA National Environmental Policy Act of 1969 NI Resource present, but not affected to a degree that detailed analysis is required NICNAS National Industrial Chemicals Notification and Assessment Scheme NO2 Nitrogen dioxide NP Resource “Not Present” in the area impacted by an of the alternative O3 Ozone OAQ Office air quality OHV Off-Highway Vehicle PI Resource Present with Potential for Impact – analyzed in detail PM10 Particulate Matter with an aerodynamic diameter less than 10 microns PSD Prevention of Significant Deterioration Program, a part of the Clean Air Act RCRA Resource Conservation and Recovery Act RMP Resource Management Plan ROD Record of Decision ROW Right-of-Way SART Sulfidization Acidification Recycling and Thickening SO2 Sulfur Dioxide STD Sexually Transmitted Disease SPCC Spill Prevention Control and Countermeasure Plan THPO Tribal Historic Preservation Office tpd tons per day USC United States Code USFWS United States Fish and Wildlife Service UUD Unnecessary or Undue Degradation WAD weak acid dissociable WOL Whole Ore Cyanidation Leaching WOUS Waters of the US YFO Yuma Field Office 4 1 Introduction Identifying Information 1.1.1 Title, Environmental Assessment Number, Type of Project Bonanza Explorations, Inc. Copperstone Mine; DOI-BLM-AZ-C020-201-0002-EA; Mining Project 1.1.2 Applicant Name Bonanza Explorations, Inc. 1.1.3 Location of Proposed Action The Project area consists of approximately 200 acres located in the Gila and Salt River Meridian, La Paz County, Arizona, T. 6 N., R. 20 W., sec. 11, lots 3 (within), 4 (within), 5 (within), E½NE¼ (within), E½SE¼ (within), and SW¼SE¼ (within); sec. 12, N½ (within), S½ (within); sec. 13, N½ (within); sec. 14, NE¼ (within). The Project area lies within the approximately 760 acre footprint of the Cyprus Mining Corp (Freeport) property. A general location map, a mining claim map, and a property boundary map can be seen in Figure 1-1, Figure 1-2, and Figure 1-3 below. 5 Figure 1-1: General Location Map 6 Introduction and Background This Environmental Assessment (EA) has been
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