Historic, Archive Document Do not assume content reflects current scientific knowledge, policies, or practices. •i \ Reserve I aSDll .R23 3 No.335 V. 1 USDA Indian River United States Timber Department of Sale(s) Agriculture ForestService Draft Environmental Impact Statement Tongass National Forest R10-MB-335 Volume I ^ November 1997 Common Abbreviations ACMP Alaska Coastal ManagementProgram ADEC AlaskaDepartmentofEnvironmental Conservation ADF&G AlaskaDepartmentofFishand Game ANCSA AlaskaNative Claims SettlementActof 1971 ANILCA AlaskaNational InterestLands Conservation Actof1980 BMP BestManagementPractice CFL Commercial ForestLand CFR Code ofFederalRegulations COE Army Corps ofEngineers CZMA Coastal ZoneManagementActof 1976 EIS Environmental Impact Statement EPA Environmental ProtectionAgency FSH Forest ServiceHandbook GIS Geographic Information System IDT InterdisciplinaryTeam LTF LogTransferFacility LUD LandUseDesignation LWD Large WoodyDebris MBF Onethousandboardfeet MIS ManagementIndicator Species MMBF One millionboardfeet NEPA National Enviroiunental Policy Actof1969 (asamended) NFMA NationalForestManagementAct OGR Old GrowthReserves PFL ProductiveForestLand ROD RecordofDecision TLMP TongassLandManagementPlan TTRA Tongass TimberReform Act USDA United StatesDepartmentofAgriculture VCU Value ComparisonUnit VMC Visual Management Class WAA Wildlife Analysis Area . RECORD OF DECISION USDA FOREST SERVICE Kensin^on Project Final Environmental Impact Statement Juneau Ranger District Tongass National Forest - Chatham Area DECISION TO BE MADE This record documents my decision to select the alternative that will be used to develop the Plan of Operations for the Kensington Gold Project. This decision is based upon the analysis and evaluation in the Final Environmental Impact Statement. ALTERNATIVES SELECTED FOR DETAILED EVALUATION Six alternatives were evaluated, including the No Action Alternative. The range of alternatives addressed the major issues associated with this project. The five action alternatives differed from each other in the type and location of various project components. The alternatives are summarized as follows: Alternative A - No Action - As a result of this alternative, the Forest Service would not approve a Plan of Operations for the Kensington Project. This alternative precludes any mining and milling activities on National Forest System Lands at the project site under this proposal. Exploration activities would be allowed to continue, subject to applicable laws and regulations Alternative B - Applicant Proposal - This alternative consists of the project as proposed by the Kensington Venture in their Applicant Proposal, Appendix A of the Draft EIS. -Ore crushing would be underground -Ore grinding would be above ground. -Generators would be located at mill site. -Waste rock and borrow areas would be within Sherman Creek drainage. -Tailings slurry would be disposed of in an impoundment in Sherman Creek drainage. -Ophir and Sherman Creek (8,000 feet) would be diverted around the impoundment. -The spillway for the Ophir and Sherman Creek diversion would be constructed of concrete. -Water treatment methods would be alkaline chlorination and pond settling. -Discharge of tailings pond effluent would be to marine waters north of Point Sherman. -Employees would be transported from Juneau and stay at an on-site camp -Supplies would be transported to a Comet Beach facility with no breakwater. -275 Acres of land would be disturbed. 1 r : .. 2 Alternative C - Berners Bay Access - This alternative would differ from Alternative B as follows: -Spillway would be constructed of riprap. -Water treatment methods include dechlorination and enhanced pond settling. -Employees and supplies would be transported to a terminal in Slate Creek Cove in Berners Bay. Employees would be transported to the site daily by ferry. An 8.5 mile road would be built from Slate Creek Cove to the project site. There would be only an emergency camp at the site. -392 Acres of land would be disturbed. Alternative D - Sweeny Creek Tailings Disposal - Tliis alternative would differ from Alternative B in the following items. -Grinding would be located underground. -Generators would be located near Comet Beach. -Tailings disposal impoundment would be in Sweeny Creek drainage. This would require an additional 2 miles of tailings slurry line. -Sweeny Creek 6,000 feet) would be diverted around impoundment. ( -Water treatment methods would include dechlorination and enhanced pond settling. -Employees would be transported by helicopter from Bridget or Yankee Cove area. -229 Acres of land would be disturbed. Alternative E - Dewatered Tailings Disposal - This alternative differs from Alternative B as follows: -Tailings would be dewatered and disposed at one of two locations within the Sherman Creek drainage, but outside the stream channels -No major stream diversions needed. -No tailings impoundment or spillway needed. -Water treatment methods would use hydrogen peroxide to destroy cyanide and would add dechlorination. Pond settling would be designed for dewatered tailings. -237 Acres of land would be disturbed. Alternative F - This alternative was developed and analyzed in response to public comments on the DEIS and would differ from Alternative B as follows -Water treatment methods: three options have been assessed. All three options would add dechlorination and enhanced pond settling. In addition to this, the second option would filter total suspended solids (TSS) from the effluent below the tailings impoundment. The third option would dewater the CIL portion of the mill effluent. Effluent treatment methods include hydrogen peroxide cyanide destruction and chemical precipitation of the CIL mill effluent -Discharge to marine waters would be south of Point Sherman. The pipeline would be buried near the mean high tide line from the existing camp area to a point near Point Sherman. -277 Acres of land would be disturbed. 3 ENVIRONMENTALLY PREFERRED ALTERNATIVE Alternative A, No Action, is the environmentally preferred alternative. The definition of environmentally preferred is the alternative which causes the least damage to the biological and physical environment, and which best protects, preserves, and enhances historic, cultural, and natural resources. DESCRIPTION OF THE FOREST SERVICE PREFERRED ALTERNATIVE The Forest Service preferred alternative will be used in the development of the Plan of Operations for the project. Based on the analysis and evaluation in the Final Environmental Impact Statement for the Kensington Project, it is my decision to select Alternative F with water treatment Option 1. The choice of Option 1 is based on the assessment that the water discharged from the impoundment area can meet water quality criteria found in the Draft National Pollutant Discharge Elimination System (NPDES) permit by dechlorinating the mill effluent and enhancing the settling of suspended solids in the tailings impoundment with a combination of flocculants, baffles, and other design methods. These methods are estimated to enhance settling of TSS by 75 percent, thereby substantially reducing the discharge of TSS and heavy metals to Lynn Canal. Additional effluent treatment measures such as those described in Alternative F, Options 2 and 3i niay be implemented if the final NPDES permit, or ADEC mixing zone criteria require lower concentrations of TSS, cyanide, or metals in the tailings pond effluent discharge. If violations of the NPDES permit effluent standards occur, EPA may require additional treatment of the effluent. Approval of the marine discharge site identified in the Preferred Alternative is outside the jurisdiction of the Forest Service. It is included as a recommended site since it represents the only practical option to address concerns expressed about conflicts with anchoring vessels and the perceived threat to the high value fishery north of Point Sherman. The Clean Water Act requires a Certification of Reasonable Assurance with the Clean Water Act from the Alaska Department of Environmental Conservation and a National Pollutant Discharge Elimination System permit from the Ekivironmental Protection Agency before final criteria for marine effluent discharge can be determined. RATIONALE FOR THE DECISION Alternative F was selected because it best addresses the issues identified during scoping and comments received concerning the DEIS. While some alternatives might better address certain issues, the Preferred Alternative provides the best mix for addressing them at an acceptable level. Under Alternative F, all ground disturbance on National Forest System lands will be confined to one drainage. Based on comments to the DEIS and additional technical analysis, including considerations for installation, operation, and safety, I have decided to authorize operation of ore grinding facilities above ground and to allow power generating facilities to be located at the mill site. This differs from the Preferred Alternative identified in the DEIS. Approval is contingent upon design and monitoring verification by the proponent that structures housing these facilities can be designed to reduce noise