California Code, Public Resources Code - PRC § 43509

(a) The board, in consultation with the state water board and in compliance with Section 40055, shall adopt and amend regulations specifying closure plan and postclosure maintenance plan adoption procedures and uniform standards to implement Section 43601. Regulations adopted pursuant to this section shall not include standards and requirements contained in regulations adopted by the State Water Resources Control Board pursuant to Division 7 (commencing with Section 13000) of the Water Code. The regulations shall also require solid waste landfill owners or operators to calculate, and periodically revise, cost estimates for closure and for postclosure maintenance, for as long as the solid waste could have an adverse effect on the quality of the waters of the state, but not less than 30 years after closure unless all wastes are removed in accordance with federal and state law.

(b) The board may adopt regulations that authorize the adoption of both preliminary and final closure and postclosure maintenance plans. Regulations for preliminary closure and postclosure maintenance plans may require less specificity and engineering detail than final closure and postclosure maintenance plans, and these regulations shall apply only in those cases in which there is reasonable certainty that the solid waste landfill will not close for at least one year following approval of the plans. Preliminary closure and postclosure maintenance plans shall provide sufficient detail to enable the owner or operator and the board to accurately estimate the costs for closure and postclosure maintenance.

(c) If a solid waste landfill owner or operator has submitted a closure plan and postclosure maintenance plan which satisfies the requirements of this chapter, and which has been approved by the local enforcement agency, the board, and the appropriate regional water board, the plans shall be deemed to have satisfactorily complied with all state requirements for the adoption of a closure plan and postclosure maintenance plan.