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Mammoth Pacific I Replacement Project Revised Draft Environmental Impact Report

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Mammoth Pacific I Replacement Project Revised Draft Environmental Impact Report MAMMOTH PACIFIC I REPLACEMENT PROJECT REVISED DRAFT ENVIRONMENTAL IMPACT REPORT California Clearinghouse Number 2011022020 February 2012 CEQA Lead Agency: Mono County P.O. Box 2415 Mammoth Lakes, California 93546 MAMMOTH PACIFIC I REPLACEMENT PROJECT REVISED DRAFT ENVIRONMENTAL IMPACT REPORT California Clearinghouse Number 2011022020 February 2012 CEQA Lead Agency: Mono County P.O. Box 2415 Mammoth Lakes, California 93546 Project Applicant: Mammoth Pacific, L.P. P.O. Box 1584 Mammoth Lakes, California 93546 CEQA Consultants: CAJA Environmental Services, LLC and Environmental Management Associates, Inc. 588 Explorer Street Brea, California 92821 Mammoth Pacific I Replacement Project Revised Draft EIR TABLE OF CONTENTS TABLE OF CONTENTS ...........................................................................................................................................II LIST OF FIGURES ............................................................................................................................................... VIII LIST OF TABLES .................................................................................................................................................... IX LIST OF APPENDICES ............................................................................................................................................ X ACRONYMS ............................................................................................................................................................. XI SUMMARY .................................................................................................................................................................. 1 LEGAL REQUIREMENTS FOR RECIRCULATING A DRAFT EIR ............................................................. 1 ANALYSIS INCLUDED IN THE REVISED DRAFT EIR ................................................................................. 1 New or Revised MP-I Replacement Project Information from the Applicant ............................................. 1 New or Supplemental Environmental Resource Information ........................................................................ 2 Revised Cumulative Impact Analysis ............................................................................................................... 2 OVERVIEW OF THE PROPOSED PROJECT .................................................................................................. 2 EXISTING ENVIRONMENT ............................................................................................................................... 2 SUMMARY OF THE PROJECT ALTERNATIVES .......................................................................................... 5 SUMMARY OF THE ASSESSMENT .................................................................................................................. 6 1 INTRODUCTION .......................................................................................................................................... 1-1 1.1 PROJECT DESCRIPTION ...................................................................................................................... 1-1 1.2 OBJECTIVES OF THE PROPOSED PROJECT AND THE EIR ........................................................ 1-2 1.2.1 Mammoth Pacific, L.P. .................................................................................................................... 1-2 1.2.2 Mono County .................................................................................................................................... 1-2 1.3 CASA DIABLO GEOTHERMAL PROJECTS ...................................................................................... 1-4 1.4 RELATIONSHIP TO STATUTES, REGULATIONS AND OTHER PLANS ..................................... 1-5 1.4.1 County of Mono General Plan ........................................................................................................ 1-5 1.4.2 Town of Mammoth Lakes General Plan ........................................................................................ 1-7 1.4.3 Agency Required Permits ............................................................................................................... 1-7 1.5 CEQA DOCUMENT ................................................................................................................................. 1-8 1.5.1 Conformance with CEQA ............................................................................................................... 1-8 1.5.2 Public Scoping .................................................................................................................................. 1-9 1.5.3 Identified Issues and Concerns ....................................................................................................... 1-9 1.5.4 Draft EIR ........................................................................................................................................ 1-10 1.5.5 Decision to Revise and Recirculate the Draft EIR ...................................................................... 1-11 2 PROPOSED PROJECT AND ALTERNATIVES ...................................................................................... 2-1 2.1 PROPOSED PROJECT ............................................................................................................................ 2-1 2.1.1 Project Overview ............................................................................................................................. 2-1 Project Location and Access .......................................................................................................................................... 2-1 Project Design and Power Generation Technology ....................................................................................................... 2-1 M–1 Plant Startup, Transition and Operations .............................................................................................................. 2-2 2.1.2 Replacement Plant Construction and Commissioning ................................................................. 2-2 Site Access and Roads .................................................................................................................................................... 2-4 Grading and Surface Disturbance ................................................................................................................................. 2-4 Project Facilities ............................................................................................................................................................ 2-4 Transmission Interconnection ........................................................................................................................................ 2-7 Construction Work Force, Traffic and Schedule .......................................................................................................... 2-12 Construction Water and Wastes ................................................................................................................................... 2-13 2.1.3 Pipeline Route, Design and Construction .................................................................................... 2-13 2.1.4 Existing Plant Demolition ............................................................................................................. 2-14 Demolition Work Force, Traffic and Schedule ............................................................................................................. 2-17 Decommissioning and Demolition Wastes ................................................................................................................... 2-17 2.1.5 Geothermal Fluid Production and Injection Parameters ........................................................... 2-17 ii Mammoth Pacific I Replacement Project Revised Draft EIR 2.1.6 Replacement Plant Operations and Maintenance ....................................................................... 2-18 Geothermal Fluid System ............................................................................................................................................. 2-18 Motive Fluid System ..................................................................................................................................................... 2-18 Cooling System ............................................................................................................................................................ 2-19 Operations Work Force, Traffic and Schedule ............................................................................................................. 2-19 Hazardous Materials ................................................................................................................................................... 2-20 Fire Prevention and Suppression ................................................................................................................................. 2-21 Operational Emissions ................................................................................................................................................. 2-22 Operational Discharges ............................................................................................................................................... 2-23 Operational Wastes .....................................................................................................................................................
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