Final Environmental Assessment For the CONNECTIONS PUBLIC CHARTER SCHOOL MASTER PLAN Kaumana, South Hilo, Hawai‘i Tax Map Key: (3)2-5-006:141 Prepared for: Connections Public Charter School 174 Kamehameha Avenue Hilo, Hawai‘i 96720 Prepared by: Wil Chee – Planning & Environmental October 2010 FINAL ENVIRONMENTAL ASSESSMENT Connections Public Charter School, Kaumana, South Hilo, Hawaii Table of Contents ACRONYMS...............................................................................................................................................................iv 1.0 INTRODUCTION AND PROJECT SUMMARY......................................................................................1 1.1 PROJECT PROFILE ........................................................................................................................................1 1.2 PROJECT BACKGROUND ..............................................................................................................................2 1.2.1 Revised Draft Environmental Assessment (EA) ..........................................................................................2 1.3 SCOPE AND AUTHORITY ..............................................................................................................................3 1.4 PROPOSED ACTION......................................................................................................................................3 1.5 PURPOSE AND NEED FOR THE PROPOSED ACTION .......................................................................................3 1.6 SUMMARY OF POTENTIAL IMPACTS AND MITIGATION MEASURES ..............................................................4 1.7 UNRESOLVED ISSUES...................................................................................................................................5 1.8 DETERMINATION .........................................................................................................................................5 2.0 DESCRIPTION OF THE PROPOSED ACTION AND ALTERNATIVES............................................7 2.1 PROPOSED ACTION (PREFERRED ALTERNATIVE).........................................................................................7 2.1.1 Project Location ....................................................................................................................................7 2.1.2 Project Features ....................................................................................................................................7 2.1.3 Project Phasing and Construction.......................................................................................................11 2.2 ALTERNATIVES CONSIDERED ....................................................................................................................12 2.2.1 Alternative 1 (Linear Split Campus)....................................................................................................12 2.2.2 Alternative 2 (Centralized Split Campus) ............................................................................................13 2.2.3 Alternative 3 (Consolidated Campus)..................................................................................................14 2.2.4 Alternative 4 (No Action Alternative) ..................................................................................................15 2.3 ALTERNATIVES CONSIDERED AND ELIMINATED FROM FURTHER ANALYSIS .............................................15 2.3.1 Selection Criteria.................................................................................................................................15 2.3.2 Alternative Site Locations....................................................................................................................15 2.3.3 Deferred Action ...................................................................................................................................16 3.0 AFFECTED ENVIRONMENT, POTENTIAL ENVIRONMENTAL CONSEQUENCES AND MITIGATION .............................................................................................................................................41 3.1. TOPOGRAPHY, GEOLOGY, AND SOILS........................................................................................................41 3.1.1. Potential Impacts .................................................................................................................................42 3.1.2 Mitigation Measures............................................................................................................................42 3.2 KAŪMANA CAVE.......................................................................................................................................43 3.2.1 Potential Impacts .................................................................................................................................46 3.2.2 Mitigation Measures............................................................................................................................47 3.3 HYDROLOGY, SURFACE WATER, AND GROUNDWATER .............................................................................47 3.3.1 Potential Impacts .................................................................................................................................48 3.3.2 Mitigation Measures............................................................................................................................49 3.4 NATURAL HAZARDS..................................................................................................................................49 3.4.1 Potential Impacts .................................................................................................................................51 3.4.2 Mitigation Measures............................................................................................................................53 3.5 BIOLOGICAL RESOURCES ..........................................................................................................................53 3.5.1 Potential Impacts .................................................................................................................................55 3.5.2 Mitigation Measures............................................................................................................................56 3.6 AIR QUALITY ............................................................................................................................................57 3.6.1 Potential Impacts .................................................................................................................................57 3.6.2 Mitigation Measures............................................................................................................................58 3.7 ACOUSTICAL ENVIRONMENT.....................................................................................................................58 3.7.1 Potential Impacts .................................................................................................................................58 3.7.2 Mitigation Measures............................................................................................................................59 i FINAL ENVIRONMENTAL ASSESSMENT Connections Public Charter School, Kaumana, South Hilo, Hawaii 3.8 LAND USE .................................................................................................................................................59 3.8.1 Potential Impacts .................................................................................................................................60 3.8.2 Mitigation Measures............................................................................................................................60 3.9 UTILITIES ..................................................................................................................................................60 3.9.1 Potential Impacts .................................................................................................................................61 3.9.2 Mitigation Measures............................................................................................................................65 3.10 HISTORIC AND CULTURAL RESOURCES .....................................................................................................65 3.10.1 Potential Impacts ............................................................................................................................67 3.10.2 Mitigation Measures .......................................................................................................................67 3.11 VISUAL, AESTHETIC AND RECREATIONAL RESOURCES .............................................................................68 3.11.1 Potential Impacts ............................................................................................................................68 3.11.2 Mitigation Measures .......................................................................................................................69 3.12 CIRCULATION AND TRAFFIC......................................................................................................................69 3.12.1 Potential Impacts ............................................................................................................................70