1 Seismic Hazards Mapping for Project Impact –

the former FEMA Project Impact, new methodologies were developed to map liquefaction and site amplification hazards in these communities. The maps improve the ability of these communities to plan development projects, set priorities for seismic rehabilitation programs, and assess vulnerability of their infrastructure to these hazards. The map of liquefaction hazard predicts the percentage of area underlain by each surficial geology unit that will exhibit surface manifestations of liquefaction during a specific earthquake. The liquefaction maps complement the California regulatory maps of special studies zones by delineating the relative degree of hazard of subareas within the zones. The map of site amplification portrays the capability of local soil conditions to amplify ground shaking. It relies on the VS30 site classification of the Uniform Building Code and can be readily incorporated into the project review process of municipalities