Washington Revised Code Title 70A. Environmental Health and Safety § 70A.130.010. Establishment of standards for chemical contaminants in drinking water by state board of health

(1) In order to protect public health from chemical contaminants in drinking water, the state board of health shall conduct public hearings and, where technical data allow, establish by rule standards for allowable concentrations. For purposes of this chapter, the words “chemical contaminants” are limited to synthetic organic chemical contaminants and to any other contaminants which in the opinion of the board constitute a threat to public health. If adequate data to support setting of a standard is available, the state board of health shall adopt by rule a maximum contaminant level for water provided to consumers' taps. Standards set for contaminants known to be toxic shall consider both short-term and chronic toxicity. Standards set for contaminants known to be carcinogenic shall be consistent with risk levels established by the state board of health.

(2) The board shall consider the best available scientific information in establishing the standards. The board may review and revise the standards. State and local standards for chemical contaminants may be more strict than the federal standards.