Proposed Kilauea southwest rift geothermal resource subzone: Pahala, island of Hawaii

Abstract

CONTENTS Preface iii Acknowledgment iv Introduction Assessment of Geothermal Resource 2 Community Input 5 Social Impacts 6 Potential Economic Benefits 15 Environmental Impacts from Geothermal Development 18 Geologic Hazards 31 Land Use Compatibility 35 Conclusion and Recommendation 38 APPENDIX A - References A-1 CONCLUSION AND RECOMMENDATION The Department of Land and Natural Resources under the authority of Act 296, SLH 1983, and Act 151, SLH 1984, conducted an assessment of the Kilauea southwest rift zone, island of Hawaii. This land area located between the western boundary of the Hawaii Volcanoes National Park and Highway 11 was examined for resource potential and evaluations were made on geologic hazards, social, economic, and environmental impacts and compatibility of geothermal development. The potential geothermal resource area was evaluated on the basis of potential and real impacts which may occur within the identified area and considered the statutory state energy objectives and policies. The potential geothermal resource area was assessed to have a 25% to 90% probability of locating a high temperature resource. Potential impacts were identified and considerations given to mitigation measures and other requirements that may be imposed on a site-specific, case-by-case basis during subsequent State and County permitting. Geologic hazards are present throughout the entire Kilauea southwest rift zone. Decentralization of facilities, strategic siting, and lava diversion platforms and barriers may mitigate damage from future lava flows. Development permits should require that all potential economic losses are to be assumed by developers. The State Department of Health has proposed air quality standards and promulgated underground injection control regulations which will control geothermal emissions and effluent injections. Development permits should either prohibit or control surface water disposals. Geothermal noise levels have been regulated in exploration permits and such noise regulation is expected to continue throughout the development process. The proposed Kilauea southwest rift GRS will provide a 1000-foot buffer between the GRS and the Hawaii Volcanoes National Park to mitigate any possible effects on the existing flora and fauna in the National Park. Scenic view corridors along Highway 11 should be protected throughout the permitting process by requiring tasteful development, design, landscaping, and painting of structures. The State has established an objective of energy self-sufficiency and geothermal energy is viewed as a key to attaining this objective. The protection of the environment is also an area of high priority. The Division of Water and Land Development believes that both goals of geothermal development and environmental protection can be attained by permitting controlled development within the proposed Kilauea southwest rift GRS. This assessment has resulted in the identification of approximately 8, 090 acres of the Kilauea southwest rift zone as a potential geothermal resource area and recommends that the proposed Kilauea southwest rift GRS be considered for designation by the Board of Land and Natural Resources under authority of Act 296, SLH 1983, and Act 151, SLH 1984.