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Ring of Fire Proposed RMP Final EIS Volume 3

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Ring of Fire Proposed RMP Final EIS Volume 3 Ring of Fire Proposed RMP/Final EIS EXECUTIVE SUMMARY The Anchorage Field Office (AFO) of the Bureau of Land Management (BLM) has prepared a Proposed Resource Management Plan (PRMP)/Final Environmental Impact Statement (FEIS) for the Ring of Fire planning area to provide a comprehensive framework for managing and allocating uses of the public lands and resources within the Anchorage District. This planning process meets the requirements of the National Environmental Policy Act (NEPA) through a detailed description of the alternatives and environmental consequences resulting from each alternative. The Federal Land Policy and Management Act of 1976 (FLPMA) requires the Secretary of the Interior, with public involvement, to develop, maintain, and when appropriate, revise land use plans that provide tracts or areas for the use of the public lands. The Ring of Fire planning area encompasses an area from the Aleutian Islands at the southwestern tip of Alaska, through the Alaska Peninsula, parts of southcentral Alaska, through the southeast panhandle. The planning area is divided into four geographic regions: Alaska Peninsula/Aleutian Chain region, Kodiak region, southcentral region, and southeast region. Reasonably Foreseeable Development (RFD) scenarios provide a mechanism to analyze the effects that discretionary planning decisions have on mineral development based upon four alternatives. This RFD scenario is used to predict the type, location, and manner of potential disturbance due locatable minerals extraction in the planning area over the next 15 years. This report has been formulated to project and predict development regardless of specific land management authority (federal, State, Native, or private), but concentrates on the high mineral potential areas located on unencumbered BLM lands and State- and Native-selected lands. A range of four alternatives was developed during the Ring of Fire PRMP/FEIS process. These include Alternative A — No Action (Current Management), Alternative B — Resource Development, Alternative C — Resource Conservation, and Alternative D — Proposed Action. Due to the diminutive amount of BLM-managed lands within the planning area, the level of disturbance from reasonably foreseeable locatable mineral activity would be minimal. If the maximum amount of activity is allowed (Alternative B — Resource Development), an estimated total of 59 acres could potentially be disturbed in the Ring of Fire planning area. If the least amount of activity is allowed (Alternative C — Resource Conservation), an estimated total of 5 acres could potentially be disturbed on existing valid operation in the Ring of Fire planning area. If reasonable accommodations are given to all parties, (Alternative D — Proposed Action), an estimated maximum total of 59 acres could potentially be disturbed in the Ring of Fire planning area. However, due to its sensitive nature, the Neacola Mountains-Blockade Glacier area could remain closed to mineral entry and thus diminish the disturbed acreage estimate. Appendix G B-1 Attachment B Ring of Fire Proposed RMP/Final EIS 1.0 INTRODUCTION The Anchorage Field Office (AFO) of the Bureau of Land Management (BLM) has prepared a Proposed Resource Management Plan (PRMP)/Final Environmental Impact Statement (FEIS) in the Ring of Fire planning area to provide a comprehensive framework for managing and allocating uses of the public lands and resources within the Anchorage District. This planning process will meet the requirements of the National Environmental Policy Act (NEPA) through a detailed description of the alternatives and environmental consequences resulting from each alternative. The Federal Land Policy and Management Act of 1976 (FLPMA), as amended, provides the authority for the BLM land use planning on public lands. In particular, Section 202 (a) requires the Secretary of the Interior, with public involvement, to develop, maintain, and when appropriate, revise land use plans that provide by tracts or areas for the use of the public lands. Implementing regulations are contained in 43 Code of Federal Regulations (CFR) 1610. BLM Manual, 1601 Land Use Planning, and a handbook (H-1601-1 Land Use Planning Handbook), provide procedures and guidance for the planning process. The Ring of Fire planning area encompasses an area some 2,500 miles long, from the Aleutian Islands at the southwestern tip of Alaska, through the Alaska Peninsula, parts of southcentral Alaska, through the southeast panhandle. The planning area is divided into four geographic regions: (1) Alaska Peninsula/Aleutian Chain region, (2) Kodiak region, (3) southcentral region, and (4) southeast region. The southcentral region includes the Cook Inlet area, Matanuska- Susitna Valley, and Kenai Peninsula, but excludes eastern Prince William Sound (PWS) and the Wrangell Mountains to the east. The southeast region extends from Yakutat Bay to the southeastern tip of Alaska. This Reasonably Foreseeable Development (RFD) scenario: 1) provides a mechanism to analyze the effects that discretionary planning decisions have on mineral development, and 2) summarizes basic information used in developing the various alternatives analyzed in the NEPA document. By incorporating available geologic and economic information, as well as utilizing federal and State mineral assessment reports, this RFD scenario is used to predict the type, location, and manner of potential locatable mineral extraction in the Ring of Fire planning area over the next 15 years. RFD scenario's have been formulated to project and predict development regardless of specific land management authority, federal, State, Native, or private; but concentrates on the high mineral potential areas located on unencumbered BLM land and State- and Native-selected lands. The following sections present what has been identified about the geology, known mineral occurrences, and unknown potential of the Ring of Fire planning area. Appendix G B-2� Attachment B Ring of Fire Proposed RMP/Final EIS 2.0 DESCRIPTION OF GEOLOGY 2.1.1 Mineral Terranes I The Ring of Fire planning area is underlain by 13 mineral terrane units whose geologic settings are considered highly favorable for the existence of metallic mineral resources (Arctic Environmental Information and Data Center [AEIDC] 1982, Resource Data, Inc. [RDI] et al. 1995). The geologic nature of each terrane will determine specific commodities and mineral deposit types. Unmapped areas are generally evaluated as having poor to only moderate mineral potential. Mineral terranes located within each region are discussed below and listed in Table 1 and shown in Figures 1 through 3. Table 1.MMineral Terranes Identified in the Ring of Fire Planning Area Map unit Name Description Favorable deposits IGA Alkalic granitic rocks Syenite, locally including Uranium, rare earth elements, peralkaline granite and monzonite and molybdenum IGF Felsic granitic rocks Granite and quartz monzonite Tin, tungsten, molybdenum, uranium, and thorium IGI Intermediate granitic Granodiorite and quartz diorite Copper, gold, and rocks molybdenum IGU Undivided granitic Granite Uranium, thorium, rare earth rocks elements, tin, tungsten, molybdenum, copper, and gold IMA Mafic intrusive rocks Gabbro, locally including mafic-rich Copper and nickel with intermediate rocks including mafic byproduct platinum and cobalt monzonite and diorite IUM Ultramafic rocks Peridotite and dunite Chromium, nickel, and platinum group metals with byproduct cobalt SCB Continental Coal-bearing sandstone, shale, Coal and uranium with sedimentary rocks and conglomerate byproduct vanadium SGS Graywacke and shale Interbedded with minor volcanic Gold or a variety of metals rocks VFI Intermediate volcanic Trachyandesite and andesite Uranium and thorium rocks VFU Felsic volcanic rocks Undivided hyolite and quartz latite Copper, lead, and zinc with b •roduct silver and •old VMU Mafic volcanic rocks Undivided primarily basalt Copper and zinc with b •roduct silver and •old VSF Sedimentary and Undivided rhyolite, quartz latite, Copper and zinc with felsic volcanic rocks and associated sediments b roduct silver and old VSM Sedimentary and Undivided basalt and associated Copper and zinc with 1.­ mafic volcanic rocks sediments byproduct silver and gold Alaska Peninsula/Aleutian Chain Region: Felsic granitic rocks; favorable for tin, tungsten, molybdenum, uranium, and thorium deposits. Intermediate granitic rocks; favorable for copper, gold, and molybdenum deposits. Coal-bearing sedimentary rocks; favorable for coal and uranium with byproduct vanadium deposits. Felsic and intermediate volcanic rocks; favorable for epithermal gold, silver, and mercury deposits. Undivided mafic volcanic rocks; favorable for copper and zinc deposits with byproducts of silver and gold. Undivided sedimentary and felsic volcanic rocks; favorable for copper, lead, and zinc deposits with byproducts of silver and gold. Undivided sedimentary and mafic volcanic rocks; favorable for copper and zinc deposits with byproducts of silver and gold (Figure 1). Appendix G B-3 Attachment B Ring of Fire Proposed RMP/Final EIS Kodiak Region: Felsic granitic rocks; favorable for tin, tungsten, molybdenum, uranium, and thorium deposits. Intermediate granitic rocks; favorable for copper, gold, and molybdenum deposits. Ultramafic rocks; favorable for chromium, nickel, and platinum group metal deposits with byproduct of cobalt. Graywacke and shale; favorable for gold deposits or a variety of metals. Undivided sedimentary and mafic volcanic rocks; favorable
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