Cal. Health & Safety Code § 25208.13

(a) If the regional board determines that certain mining wastes have properties so that the wastes do not pollute or threaten to pollute the waters of the state when discharged into a surface impoundment which is in compliance with all applicable regulations adopted by the state board pursuant to Division 7 (commencing with Section 13000) of the Water Code, the regional board may exempt a surface impoundment into which these mining wastes are discharged from Sections 25208.4 and 25208.5, pursuant to subdivision (b).
(b) A person may apply to a regional board authorized pursuant to subdivision (a) for an exemption from Section 25208.4 or 25208.5, or from both sections, for a surface impoundment, into which mining wastes are discharged 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 January 1, 1986. Except as provided in subdivision (c), the initial application for exemption shall include a completed hydrogeological assessment report which contains the accurate data and documentation specified in Section 25208.8. A regional board may grant the applicant an exemption from Section 25208.4 or 25208.5, or both, if the regional board makes both of the following findings:
1. (1) The applicant for the exemption has fully complied with all the applicable regulations adopted by the state board for mining waste.
2. (2) The surface impoundment does not pollute or threaten to pollute the waters of the state.
(c) If the regional board grants an exemption pursuant to subdivision (b), the regional board shall revise the waste discharge requirements prescribed pursuant to Section 13263 of the Water Code for that surface impoundment based upon a review of the report and shall include conditions in the waste discharge requirement to ensure that the waters of the state will not be polluted or threatened with pollution. Except as hereafter provided, if the regional board does not grant the exemption within two years of the date of application, the applicant shall comply with the requirements specified in either Section 25208.4 or 25208.5, or with both sections, whichever is applicable, within three years from the initial date of application. If the applicant submitted the hydrogeologic assessment report on or before January 1, 1986, and the regional board determines that the report submitted contains insufficient information to allow the regional board to complete a reasoned evaluation and the applicant did not receive notice in writing of the deficiencies on or before January 1, 1988, the applicant may be granted up to a maximum of one year from the date of written notification of the deficiencies for the sole purpose of providing the information necessary to correct the deficiencies. Upon receipt of the additional information, the regional board shall complete the evaluation and may grant an exemption in accordance with this section within 60 days. If the regional board denies the exemption, the applicant shall comply with the requirements specified in either Section 25208.4 or 25208.5, or with both sections, whichever is applicable, within one year of the date of denial.
(d) An exemption granted pursuant to subdivision (b) shall not be effective for more than five years. A regional board shall not renew the exemption unless the regional board makes the findings specified in subdivision (b).
(e) 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.
(f) If a regional board determines that a surface impoundment granted an exemption pursuant to subdivision (b) is polluting the waters of the state, the regional board shall take all of the actions specified in Section 25208.6.