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Mitigation Measure: Hawaii County Department of Parks and Recreation will ensure that all structures and improvements conform to Chapter 27 of the Hawaii County Code in order to avoid impacts to the floodplain. 3.2.2 Lava Flow and Earthquake Hazards Environmental Setting The entire Big Island is subject to geologic hazards, especially lava flows and earthquakes. The project site is located in Lava FIow Hazard Zone 3 (on a scale of ascending risk 9 to 1). Zone 3 is considered "less hazardous than [Z)one 2 [which is adjacent to and downslope of active risk zones] because of greater distance from recently active vents and/or because the topography makes it less Iikely that flows will cover these areas" (Heliker 1990). As such, there is some risk of lava inundation over relatively short time scales. In terms of seismic risk, the entire Island of Hawaii is rated Zone 4 Seismic Probability Rating (Uniform Building Code, Appendix Chapter 25, Section 2518). Zone 4 areas are at risk from major earthquake damage, especially to structures that are poorly designed or built. Partly owing to the lack of unconsolidated sediments in the local substrate, none of the several earthquakes of Richter magnitude 6.0 or greater that have occurred in the Hilo area since 1950 has caused substantial damage to well- engineered roads, bridges or other roadway structures. Slopes in the areas planned for construction average approximately 8 percent or less, and are not anticipated to pose any problems in site design and preparation. Some construction involving cantilevered construction may occur in higher slope areas. Impacts and Mitigation Measures In general, geologic conditions impose no constraints on the project. Although the project is located in an area exposed to geologic hazard, any park that would service residents of this area must be located within such an area, and there are thus no reasonable alternatives. Mitigation Measure: All construction will conform with lateral load specifications according the Uniform Building Code in order to reduce Potential damage from location in a high seismic risk area. 13