Cal. Health & Saf. Code § 116751
The Department of Fish and Wildlife shall not introduce a poison to a drinking water supply for purposes of fisheries management unless the state board determines that the activity will not have a permanent adverse impact on the quality of the drinking water supply or wells connected to the drinking water supply. In making this determination, the state board shall evaluate the short- and long-term health effects of the poison in drinking water, ensure that an alternative supply of drinking water is provided to the users of the drinking water supply while the activity takes place, and, in cooperation with the Department of Fish and Wildlife, develop and implement a monitoring program to ensure that no detectable residuals of the poison, breakdown products, and other components of the poison formulation remain in the drinking water supply or adjoining wells after the activity is completed.
Ca. Health and Saf. Code § 116751