PD BACKGROUND REPORT (REZ-21-247)

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the State's classification system does not recognize this site as being agriculturally important. The U. S. Soil Conservation Service, however, has designated the soil type in this are to be of the Keaukaha extremely rocky muck (rKFD) series, 6 to 20 percent slopes. This soil type consists of well-drained, think (less than 1 foot) organic soils overlying pahoehoe lava bedrock. Runoff is medium, erosion hazard slight, and shrink-swell potential high. These soils are usually moist, but when dried, they have high shrinkage but low swelling potential. This soil type is widespread throughout downtown Hilo. C. Natural Hazards 1. Drainage The US Corps of Engineers' Flood Insurance Rate Map (FIRM) designates the area of the proposed development to be in Zone X (areas outside of 500-year flood). There are no drainage ways through the site. Accordingly, the site has not and should not be subject to flooding. As there will be an added level of impervious surface resulting from the proposed parking area, there may be an issue relating to potential increased run-off. In that event, drywell or similar type of accommodations will be implemented, subject to the review and approval of the Department of Public Works. The depth of these drywells - if needed - will be sufficient to avoid potentially high groundwater table. 2. Tsunami Hazard The subject site is situated over a mile from the ocean and is outside of the Civil Defense's Tsunami Evacuation Zone. 3. Volcanic and Earthquake Hazards The United States Geological Survey (USGS) classifies the entire City of Hilo as being within Lava Flow Hazard Zone 3; on a scale of ascending risk, 9 to 1. There is little that can be done to mitigate this situation and reflects an ongoing threat to all residents and businesses. The entire island of Hawaii falls within Earthquake Zone 4, according to the County Building Code. As such, the Applicant understands