1. (a) The Risk Management Plan shall include a protocol to evaluate corrosion and to establish a corrosion risk for each gas storage well.

   1. (1) The evaluation of corrosion risk for each gas storage well shall consider at least the following:

      1. (A) Evaluation of the well's components including tubular integrity and the configuration and the likelihood of its casings to corrode.
      2. (B) The well's corrosion rate and detected anomalies, as determined under Section 1726.6, subdivision (a)(2).
      3. (C) Anomalies identified in other logs or tests.
      4. (D) The well's age, construction, history of use and maintenance, including drilling, completion, location and quality of cement, uncemented casing, mitigations and repairs, replacements, and current use.

      5. (E) Evaluation by well of environmental conditions including at least the following:

         1. (i) Composition and anticipated corrosivity of wellbore fluids and solids, including the impact of operating pressures and temperatures;
         2. (ii) Composition and anticipated corrosivity of all formation fluids, including fluids in formations above the storage zone;
         3. (iii) Surface and near surface hydrology;
         4. (iv) Surface and near surface soil conditions;
         5. (v) Observed corrosion of wells within the same field; and
         6. (vi) Other environmental factors that may contribute to corrosivity.
   2. (2) Operator shall reevaluate if a corrosion risk exists after each casing wall thickness test and any time other data indicates a need for reevaluation.

2. (b) Where a corrosion risk has been established, the Risk Management Plan shall include a protocol for corrosion risk mitigation for each gas storage well that includes at least the following:

   1. (1) Strategies to prevent and/or mitigate each corrosion risk and the anticipated effectiveness of each strategy. Strategies evaluated for each well shall at a minimum include: cathodic protection; coatings; inhibitors; and material selection or replacement.

   2. (2) Evaluation of cathodic protection as a possible mitigation strategy shall be documented for each well. If cathodic protection is not implemented then the documentation shall include explanation of why cathodic protection was not selected. If cathodic protection is implemented, then the documentation shall include:

      1. (A) Description of how the cathodic protection system is used to mitigate corrosion risks, and
      2. (B) References to the industry standards used to define the protection criteria.

3. (c) The corrosion risk mitigation protocol shall include a plan for monitoring and evaluating the effectiveness of each corrosion risk mitigation strategy used.

   1. (1) The operator shall reevaluate the corrosion risk mitigation strategies in use every time casing wall thickness inspection is conducted under Section 1726.6, subdivision (a)(2) and any time other data indicates a need for reevaluation.
   2. (2) Reevaluation of corrosion risk mitigation strategies shall include consideration of newly developed corrosion mitigation technologies and practices.
4. (d) The corrosion risk mitigation protocol shall be updated after changes to mitigation strategies and shall be provided to the Division during scheduled Risk Management Plan updates submitted under 1726.3(a) and when requested by the Division.
5. (e) Records of corrosion risk evaluation and the evaluation of effectiveness of mitigation measures performed under this section are essential records for the purposes of Section 1726.4.4.

Note: Authority cited: Sections 3013, 3106 and 3180, Public Resources Code. Reference: Sections 3011, 3106, 3180, 3181, 3186.3, 3220 and 3403.5, Public Resources Code.

History

1. New section filed 5-1-2025; operative 7-1-2025 (Register 2025, No. 18).