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Underground Natural Gas Storage: Key Documents

Safety of Underground Natural Gas Storage Facilities: Interim Final Rule

On December 19, 2016, PHMSA published in the Federal Register an Interim Final Rule (IFR) that revises the Federal pipeline safety regulations to address critical safety issues related to downhole facilities, including wells, wellbore tubing, and casing, at underground natural gas storage (UNGS) facilities. This IFR responds to Section 12 of the Protecting our Infrastructure of Pipelines and Enhancing Safety (PIPES) Act of 2016, which was enacted following the serious natural gas leak at the Aliso Canyon facility in California on October 23, 2015. This IFR incorporates by reference two American Petroleum Institute (API) Recommended Practices (RP): API RP 1170, "Design and Operation of Solution-mined Salt Caverns used for Natural Gas Storage," issued in July 2015; and API RP 1171, "Functional Integrity of Natural Gas Storage in Depleted Hydrocarbon Reservoirs and Aquifer Reservoirs," issued in September 2015. More information on the IFR can be found at the Federal Register. A PDF copy of the actual published IFR is also available.

Annual Report

All owners and operators of underground storage facilities used for the storage of natural gas, as defined in 49 CFR part 192, are required to submit annual reports. PHMSA published a Federal Register Notice (FRN) announcing the OMB approval of this requirement. In response to this requirement, facility operators must have submitted their first annual report for the 2017 calendar year by March 15, 2018.

Operators can find the Current UNGS Annual Report Form (PHMSA F 7100.4-1 for calendar years 2017 and beyond) and instructions for completing the form by following this link and then clicking on "Operator Reports Submitted to PHMSA - Forms and Instructions" under Related Links. This will download a zipped file of PHMSA report forms and instructions.

UNGS Facility Safety Site Assessment Report

In preparation for the development of PHMSA's UNGS facilities inspection and enforcement efforts, PHMSA and additional subject matter experts formed a team to conduct facility safety site assessments at a cross-section of UNGS operators from May to July 2017. Since this work was conducted prior to the January 2018 compliance date, the site assessments were not inspections, and no deficiencies, notices, reports, or enforcement actions were issued by PHMSA as a result of the assessments. The purpose of these facility safety site assessments was to obtain information from operators to compile a summary of typical and best UNGS industry practices, gather feedback from operators regarding the technical aspects of the referenced recommended practices, and assess the level of progress being made by operators toward compliance with the pending requirements of the IFR. The results of these site assessments are being used in the development of inspection materials and enforcement guidance, and for consideration during the overall development of PHMSA's UNGS program.

The Assessment Report provides the general observations drawn solely from the discussions with the eight operators visited by the PHMSA team during the site assessments. PHMSA thanks the UNGS facility operators who voluntarily participated in this assessment effort.

Interagency Task Force on Natural Gas Storage Safety (2015-2016)

In the wake of the Aliso Canyon Underground Natural Gas Storage Facility incident in 2015, the Interagency Task Force on Natural Gas Storage Safety was formed. Three working groups were established within the Task Force for research and analysis.

  1. The "Well Integrity" working group looked at the physical integrity of wells at gas storage facilities. This group was led by the U.S. Department of Energy's (DOE) Office of Fossil Energy, with important contributions from four DOE National Labs — the National Energy Technology Laboratory, Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, and Sandia National Laboratories — and PHMSA.
  2. The "Reliability" working group looked at the reliability of natural gas supplies from gas storage facilities. This group was led by the DOE Office of Electricity Delivery and Energy Reliability, with important contributions by DOE's Argonne National Laboratory, DOE's Energy Information Administration, and the Federal Energy Regulatory Commission (FERC).
  3. The "Health and Environment" working group looked at the public health and environmental impacts associated with the Aliso Canyon leak. This group was led by the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Health and Human Services (HHS) Centers for Disease Control and Prevention (CDC). The U.S. Department of Commerce's (DOC) National Oceanographic and Atmospheric Administration (NOAA) and PHMSA also contributed.

The Interagency Task Force Final Report is a synthesis of the three working group reports, which are made available as separate technical appendices to the report. The full report includes all 44 specific recommendations of the Task Force. DOE has also posted a Fact Sheet summarizing the Task Force recommendations.

PHMSA initiated regulatory actions to help ensure the safety of natural gas storage facilities across the country with the issuance of the IFR on December 19, 2016. Moving forward, PHMSA will consider the recommendations of the Interagency Task Force in developing future regulation and safety standards as required by the PIPES Act of 2016 (P.L. 114-183).

PHMSA Advisory Bulletins

  • ADB-2016-02: Pipeline Safety: Safe Operations of Underground Storage Facilities for Natural Gas [Docket No. PHMSA-2016-0016], issued February 5, 2016.
  • ADB-97-04: Underground Storage of Natural Gas or Hazardous Liquids

Industry Documents

The Interstate Oil and Gas Compact Commission (IOGCC), a multi-state government agency that promotes conservation of domestic oil and natural gas resources, and the Ground Water Protection Council (GWPC), a nonprofit organization consisting of state ground water regulatory agencies to promote conservation of ground water resources, organized the States First Initiative to facilitate multi-state collaboration and regulatory solutions for oil and natural gas producing states.

In 1995, the IOGCC published the following report "Natural Gas Storage in Salt Caverns-A Guide for State Regulators". The report was updated in 1998.  

Last updated: Tuesday, September 11, 2018