Equitrans Midstream says November gas leak caused by failure due to corrosion

Aug 24 (Reuters) - Equitrans Midstream Corp said on Thursday water and oxygen induced corrosion caused failure of a well casing at its Rager Mountain storage facility in Pennsylvania in November last year, which resulted in a natural gas leak.

The cumulative natural gas loss from the leak was 1.16 billion cubic feet (bcf), the U.S. energy company said in a statement, of which 1.04 bcf was vented to the atmosphere.

For comparison, the leak at Southern California Gas Co's Aliso Canyon gas storage facility in California, often cited as the biggest gas leak in U.S. history, released about 4.6 bcf of gas, or methane, from October 2015 to February 2016.

Rager Mountain, which can store 9 bcf of gas, was converted to a storage facility after the oil and gas was exhausted. (Reporting by Arshreet Singh in Bengaluru; Editing by Shailesh Kuber)