1. Criteria. Seismic hazard areas are generally those areas susceptible to ground failure during seismic events. Failure can consist of soil liquefaction, slope failure, settlement, ground rupture, or lateral displacement. Settlement and soil liquefaction conditions occur in areas underlain by cohesionless soils, usually fine sand, of low density, typically in association with a shallow ground water table.

2. Mapping. Seismic hazard areas may be identified using the Geologic Map of the Steilacoom 7.5-Minute Quadrangle, Washington 2003; and the “Preliminary Liquefaction Susceptibility Map of Pierce County, Washington, September 2003” published by the Washington Department of Natural Resources. [Ord. 362 § 3, 2004.]