California Supreme Court Watch

#25-321 Camarillo Sanitary Dist. v. State Water Resources Control Bd., S292989. (F087362; 113 Cal.App.5th 407; Fresno County Superior Court; 22CECG02195.) Petition for review after the Court of Appeal affirmed in part and reversed in part the judgment in a civil action and remanded for further proceedings. The court limited review to the following issues: (1) Whether the adoption by the State Water Resources Control Board (State Board) of a statistical approach for measuring water toxicity — called the Test of Significant Toxicity or “TST” — recommended in guidance issued by the U.S. Environmental Protection Agency (EPA) violates federal regulations implementing the Clean Water Act. (See 40 C.F.R. §§ 122.44, 136.3(a).) (2) Whether the interpretations of those regulations provided by the EPA and the State Board are entitled to deference under Auer v. Robbins (1997) 519 U.S. 452 and Yamaha Corporation of America v. State Board of Equalization (1998) 19 Cal.4th 1, respectively.

Petition for review granted; issues limited: 11/12/2025

See the Court of Appeal Opinion.