California Code, Public Utilities Code - PUC § 957

(a)(1) Unless the commission determines that it is prohibited from doing so by subdivision (c) of Section 60104 of Title 49 of the United States Code, the commission shall require the installation of automatic shutoff or remote controlled sectionalized block valves on both of the following facilities, if it determines those valves are necessary for the protection of the public:

(2) Each owner or operator of a commission-regulated gas pipeline facility that is an intrastate transmission line shall provide the commission with a valve location plan, along with any recommendations for valve locations. The commission may make modifications to the valve location plan or provide for variations from any location requirements adopted by the commission pursuant to this section that it deems necessary or appropriate and consistent with protection of the public.

(3) The commission shall additionally establish action timelines, adopt standards for how to prioritize installation of automatic shutoff or remote controlled sectionalized block valves pursuant to paragraph (1), ensure that remote and automatic shutoff valves are installed as quickly as is reasonably possible, and establish ongoing procedures for monitoring progress in achieving the requirements of this section.