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Chapter 6:Hazard Analysis—Landslides and Rock Falls <br /> 6.5.2 Future Plans <br /> Improving the landslide susceptibility map: <br /> Project Description Status <br /> New UH study is to generate GIS maps are included,which To start in 2010,completion <br /> potential slope stability hazard could be used for prioritization of subsequent to this hazard <br /> maps which could be used to investigations as well as assessment mitigation plan update <br /> identify zones that may warrant tools for earthquake preparedness. <br /> further detailed evaluation during UH will take the URS'information <br /> project planning. from the landslide-potential map to <br /> develop 2nd generation maps that <br /> will identify priority criteria and <br /> critical areas for more detailed <br /> study(e.g.,road cuts and lifelines). <br /> • Subdivide the island into subtracts for slope hazards to allow practical use of more <br /> slope susceptibility categories giving greater resolution. Digital file sizes limited the <br /> island wide mapping to 3 slope angle categories. Resolution of the final mapping <br /> varies from layer to layer due to disparate data sources. The scale of the 17" x 22" <br /> map is 1:333,732. <br /> • Refine key slope areas, colluvium, debris flows and poor soils intersect w/boring <br /> data and shear strike measurements (field and from maps). <br /> • Refine soil wetness map with well and groundwater model data. <br /> • Incorporate final HDOT RHRS data. <br /> • Validate estimated generalized allowable slope angle relationship for local <br /> fractured/weathered basalts, soils, and ash with lab testing. <br /> • Incorporate more detailed offshore submarine slope modeling. <br /> • Incorporate more detailed USGS slope modeling with: <br /> • Simple rigid block deformation modeling(Newmark)using shallow friction <br /> behavior of basalts and andesites, ignoring soil strength. <br /> • Assigning spatial probability& susceptibility by event <br /> • Mapping of critical accelerations using Factor of Safety contours. <br /> • Consider inaccessible damages on very steep (>60degrees)high(>1000ft) <br /> cliffs at the North Kohala Ditch and general trends of landslide damage on <br /> leeward(west) slopes. <br /> 6-9 Hawaii County Multi-Hazard Mitigation Plan <br />