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The intent of the Alquist Priolo (AP) Act and related Fault Zone Maps is to prevent the property damage and possible loss of life when structures are built directly on the surface trace of active faults. The AP act along with the Seismic Hazards Mapping Act (1990) direct the State Geologist to delineate regulatory "Zones of Required Investigation".

The regulatory maps for the affected cities and counties are published by the State Geologist and are available for download at the Regulatory Maps portal at the California Department of Conservation (CDMG)/ California Geological Survey (CGS) website.

Regulatory Maps Portal

U.S. Geological Survey, General Information Product 15, 2005

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