Section 1726.5 - Well Construction Requirements(a) Operators shall design, construct, modify, and maintain gas storage wells and every other well that penetrates the gas storage reservoir of the operator's underground gas storage project to effectively ensure mechanical integrity under anticipated operating conditions for the underground gas storage project. The operator shall ensure that a single point of failure does not pose an immediate threat of loss of control of fluids and make certain that integrity concerns with a gas storage well are identified and addressed before they can become a threat to life, health, property, the environment, or natural resources. This section does not apply to wells that have been plugged and abandoned in accordance with Public Resources Code section 3208.(b) Operators can demonstrate that a gas storage well adheres to the performance standard in subdivision (a) by demonstrating all of the following:(1) The well has been constructed with both primary and secondary mechanical well barriers to isolate the storage gas within the storage reservoir and transfer storage gas from the surface into and out of the storage reservoir. (A) The primary mechanical barrier is the barrier that is exposed to the withdrawal or injection flow stream. The primary mechanical barrier shall be able to withstand full operating pressure as demonstrated by the pressure testing required under Section 1726.6, subdivision (a)(3), and through annular pressure monitoring as required under Section 1726.7, subdivision (a). An example of a well configuration that meets the minimum requirements for a primary mechanical barrier is a well configuration that includes: (i) A wellhead master valve;(ii) Tubing hanger with seals;(iii) Production tubing; and(iv) A production packer.(B) The secondary mechanical barrier is not exposed to the withdrawal or injection flow stream under normal operations. The secondary mechanical barrier shall be able to withstand full operating pressure as demonstrated by the pressure testing required under Section 1726.6, subdivision (a)(3), and casing evaluation logs as required under Section 1726.6, subdivision (a)(2). In the event of a primary mechanical barrier failure, the secondary mechanical barrier shall be able to contain the leaking fluids until the primary mechanical barrier is reestablished. An example of a well configuration that meets the minimum requirements for a secondary mechanical barrier is a well configuration that includes:(i) Wellhead components, including casing hanger and seal assembly; and(ii) Production casing to surface.(2) Each string of casing is designed to safely contain the expected internal and external pressures and tensile loads.(3) The surface casing is of sufficient size, weight, grade, competency, and depth to support subsequent drilling operations.(4) The production casing is of sufficient size, weight, grade, competency, and depth to maintain the well integrity, and is compatible with fluid chemical composition. The production casing is designed to accommodate fluids on injection and withdrawal at the maximum expected operational pressures and velocities. The production casing is free of open perforations or holes other than the planned completion interval(s). Perforations created for investigative or remedial work are sealed to establish hydraulic isolation.(5) Casing connections are appropriate for use in the well design and exceed the expected mechanical loads.(6) The gas storage well is cemented so as to maintain the integrity of the storage zone(s) by providing isolation of the reservoir and preventing communication of fluids from the storage zone or other zones of interest.(7) All casing was cemented in a manner that ensures proper distribution and bonding of cement in the annular spaces. Additionally, cementing operations meet or exceed the following requirements: (A) Surface casing is cemented with sufficient cement to fill the annular space from the shoe to the surface to protect ground water.(B) Intermediate and production casings, if not cemented to the surface, are cemented in accordance with the requirements of Section 1722.4.(8) For new wells, the cementing operations used a cement slurry designed for the anticipated wellbore and formation conditions.(9) Cement plugs provide for effective zonal isolation.(10) Any remedial cement slurry and placement techniques are designed for the specific wellbore conditions, formations, and type of repairs.(11) Cement bond log or evaluation is on file that indicates an adequate cement bond between the casing, cement, and geologic formations. A competent cement bond extends across the confining strata, and at least 100 feet above the gas storage reservoir.(12) For wells equipped with tubing and packer, packer is set in cemented casing within confining strata or other appropriate location.(c) If the operator does not demonstrate that a gas storage well meets the criteria of subdivision (b), then the operator shall demonstrate that an alternative method of well design and construction has been employed that effectively adheres to the performance standard of subdivision (a). An alternative method of well design and construction under this subdivision shall include both primary and secondary mechanical well barriers to isolate the storage gas within the storage reservoir and transfer storage gas from the surface into and out of the storage reservoir. The Division will determine on a case-by-case basis whether the operator has effectively demonstrated that a gas storage well that does not conform to the criteria in subdivision (b) meets the performance standard in subdivision (a).(d) The requirements of this section are in addition to all other well construction requirements of this chapter.Cal. Code Regs. Tit. 14, § 1726.5
1. New section filed 6-28-2018; operative 10-1-2018 (Register 2018, No. 26). Note: Authority cited: Sections 3013, 3106 and 3180, Public Resources Code. Reference: Sections 3106, 3180, 3220 and 3403.5, Public Resources Code.
1. New section filed 6-28-2018; operative 10/1/2018 (Register 2018, No. 26).