Linking HAZUS-MH Risk-Analysis Methodology to Contaminant-Release Models

Abstract

In seismically active areas, waste-containment systems (WCS) can be damaged by earthquakes that generate significant ground acceleration. In such circumstances, contaminants can be released into the environment. Current state-of-the-art earthquake damage risk-assessment methodologies, Hazards U.S. Multi-Hazard (HAZUS-MH), need to incorporate contaminant-release models to enable more complete environmental impact assessments for existing and planned waste-containment systems. Contaminant-release and transport probabilities that determine the prospect of functional failure of waste-containment systems depend on a wider range of structural, geologic, hydrologic, and human factors than are covered by the structural failure probabilities of conventional structures such as buildings, roads, and bridges. The release of contaminants from WCS, and the cost of remediation depend on conditional probabilities that span the intensity and frequency of the initiating event, the structural damage of the WCS, and the fate and transport of the released contaminants in the subsurface. In this paper, the necessity and approach to linking HAZUS-MH to contaminant-release models are discussed along with relevant factors. The quantitative link that is advocated in this paper would expand the utility of HAZUS-MH in facilities design and environmental impact assessments.