Cal. Health & Safety Code § 25208.16

(a) A person may apply to the regional board for an exemption from subdivision (c) of Section 25208.4 for a surface impoundment into which restricted hazardous wastes that do not contain cyanide wastes or polychlorinated biphenyls (PCBs) in concentrations specified in paragraphs (1) and (4) of subdivision (a) of Section 25122.7 are discharged for the purpose of onsite temporary storage and treatment by filing an application with the regional board. If the surface impoundment was constructed before January 1, 1984, the person shall file the application with a regional board by March 1, 1986. The initial application for exemption shall include a completed hydrogeological assessment report that contains the accurate data and documentation specified in Section 25208.8. A regional board may grant the applicant an exemption from subdivision (c) of Section 25208.4 if the regional board makes all of the following findings:
1. (1) No extremely hazardous wastes are currently being discharged into the surface impoundment, and either one of the following applies:
  1. (A) The records of the person applying for the exemption indicate that no extremely hazardous wastes have been discharged into the surface impoundment.
  2. (B) Extremely hazardous wastes are not present in the surface impoundment, in the vadose zone, or in the waters of the state.
2. (2) The surface impoundment is used for the purpose of temporary storage and noncontinuous batch treatment, all hazardous wastes are removed after each batch treatment within 30 days from the date of discharge into the impoundment, and the surface impoundment is visually inspected prior to each use, tested for integrity at least annually, and is in compliance with subdivision (a) of Section 25208.7. A report of this test shall be filed with the regional board.
3. (3) The surface impoundment is in compliance with Section 25208.5 and a report has been filed pursuant to Section 25208.8.
(b) For purposes of this section, “treatment” means any method of neutralization and precipitation of metals from an acidic solution that changes the physical or chemical characteristics of the restricted hazardous waste so as to render it less harmful to the quality of the waters of the state, safer to handle, or easier to contain or manage.
(c) An exemption granted pursuant to subdivision (a) shall be effective for not more than five years. A regional board shall not renew the exemption unless the regional board makes the findings specified in subdivision (a).
(d) Applications for an exemption or renewal of an exemption shall be accompanied by the fee specified in the fee schedule adopted by the state board pursuant to Section 25208.3.
(e) If a regional board determines that a surface impoundment granted an exemption pursuant to subdivision (a) is polluting, or threatening to pollute, the waters of the state, the regional board shall take all of the actions specified in Section 25208.6.
(f) The exemption authorized by this section shall be available only for surface impoundments used for the temporary storage and treatment of boiler cleaning wastes at fossil-fueled powerplants owned or operated by a public utility subject to the jurisdiction of the Public Utilities Commission used to generate electricity for sale to the public, except that a public utility that has secured an exemption under this section may transfer that exemption to a subsequent owner of the fossil-fueled powerplant, regardless of whether the subsequent owner is a public utility subject to the jurisdiction of the Public Utilities Commission or sells the electricity generated to the public, if all of the conditions of subdivision (i) are met. If the exemption is transferred, all the requirements of this section shall apply to the subsequent owner. A subsequent owner may, in turn, transfer the exemption to another subsequent owner if all the conditions of subdivision (i) are met at the time of that transfer.
(g) For purposes of this section, any surface impoundment located within one-half mile up gradient of a potential source of drinking water shall comply with the requirements for double liners, leachate collection systems, and groundwater monitoring specified in subdivision (a) of Section 25208.5, and shall not be granted an exemption pursuant to subdivision (c) of Section 25208.5.
(h) For purposes of this section, any surface impoundment not located within one-half mile up gradient of a potential source of drinking water shall be equipped with double liners, a leachate collection system, and groundwater monitoring. The leachate collection system and groundwater monitoring required by this subdivision shall be consistent with the requirements specified in subdivision (a) of Section 25208.5. The requirements for double liners in this section may be satisfied by double liners made of synthetic or other materials with a permeability of not more than 1 x 10-7 centimeters per second. If a substantial breach of the top liner in any surface impoundment covered by this subdivision is detected through inspection, testing, or otherwise, the integrity of the top liner shall be restored prior to the next subsequent use of the impoundment.
(i) A subsequent owner of a fossil-fueled powerplant seeking to obtain a transfer of an exemption granted under this section shall apply for that exemption transfer to the regional board. The application may be granted by the regional board only if the regional board finds that all of the following conditions have been met:
1. (1) The subsequent owner, at the time of the transfer, will be in compliance with all requirements of this section.
2. (2) The hydrogeological assessment report, as required by subdivision (a), is on file.
3. (3) The surface impoundment has been inspected and tested for integrity within the six months prior to the date of the proposed transfer.
4. (4) The subsequent owner has obtained a transfer of the hazardous waste facilities permit applicable to the surface impoundment and has demonstrated compliance with the financial assurance and liability insurance requirements specified in Article 8 (commencing with Section 66264.140) of Chapter 14 of Division 4.5 of Title 22 of the California Code of Regulations, or any successor regulation.
5. (5) The application for transfer of the exemption is accompanied by a fee sufficient to cover the costs of processing the application, as determined by the regional board.