Underground Natural Gas Storage Facilities Overview
Underground Gas Storage (UNGS) Facilities are an important part of the energy supply chain in the United States. If you are operating a Natural Gas Facility that includes UNGS you are likely aware of the regulations governing it and the importance of compliance with these regulations.
Knowing the background helps clarify the basis for the regulations. In 2015 a major incident occurred at the Aliso Canyon natural gas storage facility located near Los Angeles, CA. The Aliso Canyon incident is still one of the largest releases of gas in the United States and raised awareness of the underground storage of gases at all levels (Local, State and Federal). As a result, PHMSA issued a UNGS interim final rule in January 2017 which was followed by the Final Rule (RIN #2137-AF22) that became effective in March 2020.
Looking at a general overview of regulations for UNGS is a good refresher if you don’t work with these rules on a frequent basis. To start the UNGS’s are regulated under 49 CFR 192, Transportation of Natural Gas and Other Gas by Pipeline. Specifically, Section 49 CFR 192.12, Underground Natural Gas Storage, that provides specific guidance for UNGS Facilities.
49 CFR 192.12 covers the following subjects and some of the overall requirements are provided.
Natural gas storage in Salt Cavern Facilities (solution mined salt caverns)
Natural gas storage in Depleted Hydrocarbon Reservoirs or Aquifer reservoirs
Discusses requirements for procedure manuals such as Operations and Maintenance (O&M) manuals and the need for Emergency Response Plans (ERP)
Provides guidance for the Integrity Management of UNGS
49 CFR 192, also incorporated by reference the following API Recommended Practice (RP) documents for UNGS:
API RP 1170, Design and Operation of Solution Mined Salt used for Natural Gas Storage, First Edition, July 2015, which covers facility geomechanical assessments, cavern well design and drilling, and solution mining techniques and operations, including monitoring and maintenance practices.
API RP 1171, Functional Integrity of Natural Gas Storage in Depleted Hydrocarbon Reservoirs and Aquifer Reservoirs, First Edition, September 2015. This RP focuses on storage well, reservoir, and fluid management for functional integrity in design, construction, operation, monitoring, maintenance, and documentation practices.
Why are these RPs especially important to an UNGS? First, any document that has been incorporated by reference, is considered code or part of the regulation. Operators must adhere to the requirements put forth in the RP. Further, Operators must use the RP edition specified in 49 CFR 192 as this the document that PHMSA will inspect or audit against. Newer versions may contain different guidance but until those versions are incorporated into 49 CFR 192, it is recommended that those editions not be used.
While 49 CFR 192.12, Underground Gas Storage, and related documents provide guidance for construction, operations, and maintenance and other requirements for the UNGS facilities, 49 CFR 191, Transportation of Natural and Other Gas by Pipeline, Annual, Incident, and Other Reporting, is the regulatory section covering reporting requirements for UNGS including but not limited to:
Requirements for annual reporting
Incident reporting
Safety Related Conditions reporting
A PHMSA inspection will cover 49 CFR 191 requirements as well those items in 49 CFR 192 and documents incorporated by reference which must be part of the operator's plans, procedures, and processes.
Operators should be aware of any State regulations where the facility they operate is located. The State may have additional requirements that exceed the minimum requirements set forth in PHMSA regulations. Where the State does not identify additional regulations, PHMSA's regulations govern. If PHMSA and the State have agreed to allow the State to have oversight and safety responsibilities, inspections will be based on PHMSA inspection question sets and may have additional questions regarding compliance with State regulations.
For example, in the State of Texas, the Railroad Commission of Texas (TRRC) has the enforcement authority for UNGS. The TRRC has two different divisions involved in the oversight of UNGS. The Oil and Gas section has reporting and testing requirements for the UNGS while the Office of Pipeline Safety has oversight and enforcement authority covering construction and operations for the facility. The State of Texas Administrative Code (TAC) has additional rules for both Solution Mined Cavern and Depleted Hydrocarbon and Aquifer reservoirs that operators in the State must follow.
49 CFR 192.12, Underground Gas Storage, specific parts of 49 CFR 191, the API RP, and State rules, if applicable, together provide the detailed requirements for the operator's processes to be compliant.
With this heightened regulatory focus on UNGS, now is a good time to review your programs for compliance with these regulations. Whether you are looking for assistance for process development, risk assessment, integrity management, or a gap analysis of current processes and assessments, contact us at Nicole.tebow@elementalcompliance.com or Lauren.tipton@elementalcompliance.com to discuss how Elemental can help you with UNGS compliance.