the IFR. PHMSA has noted that it may
revise or expand its gas storage regulations in the future. The IFR was issued
following PHMSA’s finding that “good
cause” existed to respond quickly to
safety risks to the public and to the environment.
PHMSA used the API RPs as an initial basis for its regulation of underground storage sites. API RP 1170 was
published in 2015 to provide recommendations for salt caverns used for
natural gas storage and covers geome-chanical assessments, cavern well design and drilling, and solution mining
techniques and operations, including
monitoring and maintenance practices. API RP 1171, also published in
2015, applies to natural gas storage in
depleted oil and gas and aquifer reservoirs (porous-rock storage), and focuses on storage well, reservoir, and fluid
management for functional integrity in
design, construction, operation, monitoring, maintenance, and documentation.
FIG. 1 NATURAL GAS PIPELINE, STORAGE NETWORK
Interstate pipeline
Intrastate pipeline
Depleted oil, gas feld
Aquifer
Salt cavern
FIG. 2 STORAGE TYPES
Porous-rock storage Salt dome Mined cavern