REGIONAL WATER QUALITY CONTROL BOARD

Improper waste disposal practices and sites which have been contaminated with toxic substances pose significant threats to the quality of California’s useable ground and surface water resources. This report shows, from a water quality perspective, 1) how to classify various wastes so that appropriate disposal practices may be selected, and 2) how to determine the degree to which a contaminated site should be cleaned or to which remedial action is necessary (“how clean is clean”), and 3) how these two decision-making processes are related. In California, the classification of wastes and the establishment of cleanup levels for sites which have been contaminated with toxic chemicals are performed by two separate State agencies with separate regulatory authority. The Department of Health Services (DHS) classifies wastes as ‘hazardous ’ or ‘restricted hazardous ’ and sets site cleanup/mitigatio