Cavern Storage
An underground hydrocarbon storage facility is used for the storage of liquid or liquefied hydrocarbons in an underground salt formation. An underground gas storage facility is used for the storage of natural gas or any other gaseous substance in an underground salt formation. Statewide Rules 95 and 97 require a permit to create, operate, and maintain an underground hydrocarbon storage facility or an underground gas storage facility.
A subsurface cavern created by the solution mining of salt from inside an underground salt formation may be utilized as an underground storage cavern under Statewide Rule 95 or 97, subject to any applicable requirements.
Statewide Rules 95 and 97 govern these wells. The rules address: the procedures for the filing of an application; notice and opportunity for hearing; transfer of permits; and technical and safety requirements pertinent to storage facilities. It also describes requirements for records maintenance, monitoring and reporting, testing, and plugging of wells accessing the subsurface caverns.
Applicability
Statewide Rule 95(a)(18) defines an underground hydrocarbon storage facility as a facility used for the storage of liquid or liquefied hydrocarbons in an underground salt formation, including surface and subsurface rights, appurtenances, and improvements necessary for the operation of the facility.
Statewide Rule 95(a)(8) defines a hydrocarbon storage well as a well, including the storage wellhead, casing, tubing, borehole, and cavern, used for the injection or withdrawal of liquid or liquefied hydrocarbons into or out of an underground hydrocarbon storage facility.
Statewide Rule 97(a)(14) defines an underground gas storage facility as a facility used for the storage of natural gas or any other gaseous substance in an underground salt formation, including surface and subsurface rights, appurtenances, and improvements necessary for the operation of the facility.
Statewide Rule 97(a)(6) defines a gas storage well as a well, including the storage wellhead, casing, tubing, borehole, and cavern used for the injection or withdrawal of natural gas or any other gaseous substance into or out of an underground gas storage facility.
Procedures and Guidance
The Cavern Storage Permit Procedures webpage provides guidance for how to apply for a cavern permit and requirements after a permit is issued.
Underground Storage of Natural Gas
Underground natural gas storage facilities are also regulated by the US Pipeline and Hazardous Materials Safety Administration (PHMSA). You can learn more about PHMSA's regulation at their Underground Natural Gas Storage webpage.
