1. (a) The owner or operator must record and provide a preliminary written report to the Unified Program Agency for any unauthorized release that escapes from the secondary containment, any unauthorized release from the primary containment that is described in sections 25295 and 25295.5 of the Health and Safety Code, and any of the following conditions in accordance with this section:

   1. (1) Any unauthorized release recorded under section 2670 that the owner or operator is unable to stop and clean up, or which remains under investigation eight hours after detection;

   2. (2) The discovery by the owner or operator, Unified Program Agency, or others of released hazardous substances at the site of the underground storage tanks or in the surrounding area. This includes the presence of free product or vapors in soils, basements, sewer and utility lines, and nearby surface or drinking waters;

      1. (B) The owner or operator is not required to submit a preliminary report to the Unified Program Agency if the condition described in subparagraph (A) is determined to be the result of defective equipment, the condition did not result in an unauthorized release, the defective equipment is immediately repaired or replaced, and any liquid in the interstitial space not used as part of the interstitial release detection method is immediately removed.

      (3)(A) Except as provided in subparagraph (B), unusual operating conditions observed by the owner or operator including erratic behavior of hazardous substance dispensing equipment, the sudden loss of hazardous substance from the underground storage tank, or an unexplained presence of water in the tank;

   3. (4) Monitoring results from a release detection method required under article 5 that indicate an unauthorized release may have occurred, unless the release detection equipment is found to be defective, the defective equipment is immediately repaired or replaced, and additional monitoring does not confirm the initial results.

2. (b) Within 24 hours after an unauthorized release or condition has been detected, or should have been detected, the owner or operator must notify the Unified Program Agency in writing and must investigate the unauthorized release or condition and take all the following immediate measures to stop any unauthorized release:

   1. (1) Remove as much of the hazardous substance from the underground storage tank as practical to prevent further release to the environment.
   2. (2) Visually inspect any above ground releases or exposed below ground releases and prevent further migration of the released substance into surrounding soils and groundwater.
   3. (3) Continue to monitor and mitigate any additional fire and safety hazards posed by vapors or free product that have migrated from the underground storage tank excavation zone and entered into subsurface structures, such as sewers or basements.
   4. (4) Remedy hazards posed by contaminated soils that are excavated or exposed as a result of release confirmation and response activities. If these remedies include treatment or disposal of soils, the owner or operator must comply with all applicable State and local requirements.
   5. (5) Determine the possible presence of free product. If free product is present, begin removal thereof in accordance with section 2712 and notify the Cleanup Oversight Agency within 24 hours.
   6. (6) If necessary, or if required by the Unified Program Agency or the Cleanup Oversight Agency, the owner or operator must remove the remaining stored substance from the underground storage tank to prevent further releases to the environment or to facilitate corrective action.

3. (c) Within five days of detecting a reportable unauthorized release, the owner or operator must provide to the Unified Program Agency a preliminary written report, including, but not limited to, all the following information to the extent that the information is known at the time of filing the preliminary written report:

   1. (1) Owner's or operator's name and telephone number;
   2. (2) Facility address and the CERS ID Number;
   3. (3) A list of the types, quantities, and concentrations of hazardous substances released;
   4. (4) The approximate date of the release;
   5. (5) The date on which the release was discovered;
   6. (6) The date on which the release was stopped;
   7. (7) A description of the actions taken to control or stop the release;
   8. (8) A description of the actions, including investigations which were undertaken and will be conducted to determine the nature and extent of soil, groundwater, or surface water contamination due to the release;
   9. (9) The method(s) of cleanup implemented to date, if any, proposed cleanup actions, and a time schedule for implementing the proposed actions;
   10. (10) The method and location of disposal of the released hazardous substance and any contaminated soils, groundwater, or surface water, including copies of any hazardous waste manifests for off-site transport of these media;
   11. (11) A description of the proposed method(s) of repair or replacement of the primary and secondary containment; and
   12. (12) A description of additional actions taken to prevent future releases.
4. (d) The Unified Program Agency must submit all preliminary written reports and any sample analyses or other data subsequently received to the Cleanup Oversight Agency with jurisdiction over the site within 60 days of receipt.

5. (e) Upon submittal of a preliminary written report pursuant to subdivision (d), the Cleanup Oversight Agency must review all documents and information submitted by the Unified Program Agency within 30 days of receipt to determine whether any further investigative or corrective action is required.

   1. (1) If the Cleanup Oversight Agency determines that further investigation or corrective action is required, the Cleanup Oversight Agency must open an underground storage tank release case, convert the GeoTracker case record to the appropriate site type, and notify the responsible parties.
   2. (2) If the Cleanup Oversight Agency determines that no further investigation or corrective action is required, the Cleanup Oversight Agency must notify the owner, operator, and property owner in writing and change the GeoTracker case status accordingly.
   3. (3) The Cleanup Oversight Agency must transmit a copy of the notification issued pursuant to paragraph (1) or (2) to the Unified Program Agency and upload a copy to GeoTracker.
6. (f) If the Cleanup Oversight Agency opens an underground storage tank release case, the responsible parties must comply with all Cleanup Oversight Agency directives consistent with article 10.
7. (g) The reporting requirements of this section are in addition to any reporting requirements in section 13271 of the Water Code, State Office of Environmental Services requirements, and any other applicable laws and regulations.

Note: Authority cited: Sections 25299.3 and 25299.7, Health and Safety Code. Reference: Sections 25286, 25295, 25295.5, 25296.35 and 25404, Health and Safety Code; and 40 CFR Sections 280.52, 280.53 and 280.61-280.63.

History

1. Amendment filed 8-9-91 as an emergency; operative 8-9-91. Text remains in effect uninterrupted pursuant to Health and Safety Code section 25299.7 (Register 92, No. 14).

2. Editorial correction of printing errors in History 1 (Register 92, No. 43).

3. Amendment of section and Note filed 4-5-94; operative 5-5-94 (Register 94, No. 14).

4. Repealer and new section heading and section filed 10-28-2025; operative 1-1-2026 (Register 2025, No. 44).