AZ HB2541

Authorizes private citizens to file lawsuits against persons, the state, or political subdivisions for violations of Arizona water quality and air quality laws, expanding existing citizen suit provisions.

Reduces the pre-lawsuit notice period from 120 days to 60 days for water quality violations before a citizen can file suit.

Removes provisions that previously blocked citizen suits when the Department of Environmental Quality was investigating or processing enforcement actions, leaving only attorney general or county attorney prosecution as a bar to citizen action.

Allows courts to award injunctive relief and assess civil penalties in citizen suits, with penalties deposited into the water quality assurance revolving fund or air quality fund.

Requires courts to award litigation costs to defendants in frivolous cases and mandates interpretation consistent with federal Clean Water Act (33 U.S.C. § 1365) and Clean Air Act (42 U.S.C. § 7604) citizen suit provisions.