Cal. Code Regs. tit. 27 § 21400

Current through Register 2024 Notice Reg. No. 25, June 21, 2024
Section 21400 - SWRCB-Closure Requirements for Surface Impoundments. (C15: Section 2582)
(a) Remove Free Liquids--All free liquid remaining in a surface impoundment at the time of closure shall be removed and discharged at an approved waste management unit (Unit). All residual liquid shall be treated to eliminate free liquid.
(b) Options--Following removal and treatment of liquid waste, impoundments shall be closed in one of two ways, as approved by the RWQCB.
(1) Mandatory Clean-Closure Attempt--Unless the discharger demonstrates, and the RWQCB finds, that it is infeasible to attempt clean-closure of the impoundment, then all residual wastes, including sludges, precipitates, settled solids, and liner materials contaminated by wastes, shall be completely removed from the impoundment and discharged to an approved Unit. Remaining containment features shall be inspected for contamination and, if not contaminated, can be dismantled. Any natural geologic materials beneath or adjacent to the closed impoundment that have been contaminated shall be removed for disposal at an appropriate Unit. For surface impoundments that are successfully clean-closed, as herein described, the RWQCB shall declare the Unit no longer subject to the SWRCB-promulgated requirements of this title. If, after reasonable attempts to remove such contaminated materials, the discharger demonstrates that removal of all remaining contamination is infeasible, the surface impoundment shall be closed as a landfill or land treatment unit, as appropriate, pursuant to ¶(b)(2).
(2) Fallback Closure Options--In cases where clean-closure [under ¶(b)(1)] is infeasible, the discharger shall propose for RWQCB approval either:
(A) Closure As a Landfill--that all residual wastes, including sludges, precipitates, settled solids, and liner materials, shall be compacted, and the Unit shall be closed as a landfill pursuant to § 21090, provided that the closed Unit meets applicable standards for landfill Units in Articles 3 and 4 of Subchapter 2, Chapter 3, Subdivision 1 of this division (§ 20240 et seq.), and further provided that the moisture content of residual wastes, including sludges, does not exceed the moisture-holding capacity of the waste either before or after closure; or
(B) Closure As an LTU--for surface impoundments which contain only decomposable wastes at closure, that the Unit be closed as a land treatment unit under § 21420(a) (2 - 4).

Cal. Code Regs. Tit. 27, § 21400

1. New article 3 (sections 21400-21420) and section filed 6-18-97; operative 7-18-97 (Register 97, No. 25).

Note: Authority cited: Section 1058, Water Code. Reference: Section 13172, Water Code; and Section 43103, Public Resources Code.

1. New article 3 (sections 21400-21420) and section filed 6-18-97; operative 7-18-97 (Register 97, No. 25).