Mary Tutwiler

Cote Blanche salt dome eyed for natural gas storage

by Mary Tutwiler

Another attempt at storing compressed natural gas in yet another salt dome in south Louisiana is again drawing criticism. Henry Gas Storage, a wholly owned subsidiary of Houston-based Ranger Gas Storage, is proposing the development of an underground natural gas storage facility on Cote Blanche Island in St. Mary Parish. The company has applied to the Federal Energy Regulatory Commission to construct four natural gas storage caverns, a 12-mile natural gas pipeline and a 26-mile brine disposal pipeline through Cote Blanche Bay, according to the Daily Iberian.

The storage caverns would be located in the Cote Blanche salt dome, site of the North American Salt Co. at Cote Blanche Island. The salt mine company hired LSU civil engineering professor Robert Thoms to assess the risk to the mine workers. Thoms, a former adviser for FERC, found potential for the compressed natural gas to leak into the mine, putting the 150 salt mine workers in jeopardy.

The Daily Iberian reports that John Fallis, vice president of North American Salt Co., said, “There is simply too much risk that naturally occurring irregularities in the salt could create conduits for deadly gas to flow into the mine. We hope this warning will convince them to find a more suitable location, and that because of the significance of these issues, the Federal Energy Regulatory Commission will conduct a full environmental analysis culminating in an environmental impact statement.”

Henry Gas filed a request with FERC on Aug. 27, 2008 to initiate a review of the project. FERC approved the request on Sept. 9, and the project is moving through the federal pre-permitting process.

Because of the dense physical properties of salt crystals, salt domes are considered highly stable sites to contain compressed gasses. However, other oil and gas storage caverns located in south Louisiana salt domes have proved problematic. The Jefferson Island salt dome is the site of an ongoing fight between residents who live around Lake Peigneur and  Jefferson Island Storage and Hub, a natural gas storage company, which  owns and operates two natural gas storage caverns in the Jefferson Island salt dome. Residents complain that since the compressed natural gas has been stored in the caverns, the lake has continued to mysteriously bubble, evidence, they say, of leaks in the caverns. The Weeks Island salt dome, which at one time stored crude oil in a cavern as part of the Strategic Petroleum Reserve before being abandoned because of potential leakage into Weeks Bay, is being eyed as a place to dump toxic exploration and production waste by a Canadian oilfield waste company.