Final Environmental Assessment ANAHOLA SOLAR PROJECT ANAHOLA, KAUA‘I PREPARED FOR: Kaua‘i Island Utility Cooperative USDA Rural Utilities Service Department of Hawaiian Homelands PREPARED BY: SEPTEMBER 2013 PROJECT SUMMARY Project: Anahola Solar Project Kaua‘i Island Utility Cooperative 4463 Pāhe‘e Street Applicant: Līhu‘e, Hawai‘i 96766-2000 Contact: Brad W. Rockwell (808) 246-8289 USDA Rural Utilities Service 1400 Independence Ave. SW Mail Stop 1571 Washington, DC 20250 Approving Agency: Department of Hawaiian Home Lands State of Hawai‘i 91-5420 Kapolei Parkway Kapolei, HI 96707 Location: Anahola, Kaua‘i, Hawai‘i Installation of a ~12 MW photovoltaic facility including a dedicated substation with interconnections to the island-wide Proposed Project: electrical grid and other ancillary facilities and construction of a Transmission and Distribution service center and base yard.. Tax Map Key: (4) 4-7-004:002 Parcel Area: 422.15 acres Project Area: 60 acres Judicial District: Kawaihau State Land Use District: Agriculture County Zoning: Agriculture NEPA Environmental Assessment Chapter 343 Environmental Assessment National Pollutant Discharge Elimination System – Notice of Intent [Construction] (NPDES-NOI[C]) Noise permit Required Permits & Approvals: Construction on a State Highway Permit Certificate of Public Convenience and Necessity Grading Permit Building Permit (Service Center only) Well Construction and Pump Installation Permit Determination: Finding of No Significant Impact Parties Consulted: See Chapter 9 Planning Solutions, Inc. 210 Ward Avenue, Suite 330 Consultant: Honolulu, HI 96814 Contact: Perry White (808) 550-4483 FINAL ENVIRONMENTAL ASSESSMENT ANAHOLA SOLAR PROJECT TABLE OF CONTENTS TABLE OF CONTENTS 1. PROJECT OVERVIEW ............................................................................................................... 1-1 1.1 BACKGROUND ............................................................................................................................................1-1 1.2 PROJECT PARTICIPANTS .............................................................................................................................1-6 1.2.1 KRS One ...................................................................................................................................................1-6 1.2.2 Rural Utilities Service (RUS) Involvement ..............................................................................................1-6 1.2.3 Hawaiian Homes Involvement ..................................................................................................................1-7 1.2.4 REC Solar .................................................................................................................................................1-8 1.3 REGULATORY PROVISIONS GOVERNING THE EA ...................................................................................... 1-10 2. DESCRIPTION OF THE PROPOSED PROJECT ................................................................... 2-1 2.1 SOLAR ARRAY ...........................................................................................................................................2-1 2.1.1 Solar Array: Description ...........................................................................................................................2-1 2.1.2 Solar Array: Construction Activities ........................................................................................................2-1 2.1.3 Solar Array: Operation and Maintenance ............................................................................................... 2-10 2.1.4 Solar Array: Decommissioning............................................................................................................... 2-10 2.2 ANAHOLA SUBSTATION ............................................................................................................................ 2-11 2.2.1 Anahola Substation: Proposed Facilities ................................................................................................ 2-11 2.2.2 Anahola Substation: Construction Activities .......................................................................................... 2-17 2.2.3 Substation: Operation and Maintenance Activities ................................................................................. 2-17 2.2.4 Substation: Decommissioning ............................................................................................................... 2-18 2.3 ANAHOLA SERVICE CENTER .................................................................................................................... 2-18 2.3.1 Anahola Service Center: Construction Activities ................................................................................... 2-23 2.3.2 Anahola Service Center: Operations and Maintenance .......................................................................... 2-23 2.3.3 Anahola Service Center: Decommissioning ........................................................................................... 2-23 2.4 IMPLEMENTATION SCHEDULE .................................................................................................................. 2-23 2.5 PROJECT COSTS ........................................................................................................................................ 2-24 3. PURPOSE & NEED OF THE PROPOSED PROJECT ............................................................ 3-1 3.1 NEED FOR PHOTOVOLTAIC ARRAY AND SUBSTATION .................................................................................3-1 3.2 NEED FOR THE SERVICE CENTER ................................................................................................................3-4 3.4 OBJECTIVES & PURPOSE OF THE PROPOSED PROJECT ..............................................................................3-6 4. ALTERNATIVES EVALUATED IN THE EA .......................................................................... 4-1 4.1 NO ACTION ................................................................................................................................................4-2 4.2 SOLAR ARRAY AND SUBSTATION ALTERNATIVES CONSIDERED AND ELIMINATED ....................................4-2 4.2.1 Alternate Locations ...................................................................................................................................4-2 4.2.2 Alternate Sizes ..........................................................................................................................................4-4 4.2.3 Alternate Timing (Delayed Action) ..........................................................................................................4-5 4.3 SERVICE CENTER ALTERNATIVES CONSIDERED AND ELIMINATED ............................................................4-5 4.3.1 Alternate Size/Location ............................................................................................................................4-5 4.3.2 Alternate Timing: Delayed Action ............................................................................................................4-6 5. AFFECTED ENVIRONMENT, ENVIRONMENTAL IMPACTS, & MITIGATION MEASURES .................................................................................................................................. 5-1 5.1 TOPOGRAPHY, GEOLOGY, AND SOILS .........................................................................................................5-1 5.1.1 Existing Conditions: Topography, Geology, and Soils ............................................................................5-1 5.1.2 Probable Construction Impacts on Topography, Geology, and Soils .......................................................5-2 5.1.3 Probable Operational Impacts on Topography, Geology, and Soils .........................................................5-3 5.1.4 Probable DECOMMISSIONING IMPACTS on Topography, Geology, and Soils .................................5-4 5.2 HYDROLOGY ..............................................................................................................................................5-4 5.2.1 Existing Conditions: Hydrology ..............................................................................................................5-4 PAGE i ANAHOLA SOLAR PROJECT FINAL ENVIRONMENTAL ASSESSMENT TABLE OF CONTENTS 5.2.1.1 Existing Conditions: Surface Water .......................................................................................... 5-4 5.2.1.2 Existing Conditions: Groundwater ............................................................................................ 5-7 5.2.2 Probable Impacts: Hydrology ................................................................................................................. 5-9 5.2.2.1 Effects on Surface Runoff Volumes .......................................................................................... 5-9 5.2.2.2 Adequacy of Kūhiō Highway Storm Drainage System ........................................................... 5-11 5.2.2.3 Effects on Surface Water Quality ............................................................................................ 5-12 5.2.2.4 Effects on Groundwater ........................................................................................................... 5-14 5.2.2.5 Sanitary Wastewater Disposal ................................................................................................