Sinkhole: Vent Wells Being Drilled for Trapped Gas

The emergency preparedness director for Assumption Parish, La., says wells are being dug to vent and investigate natural gas trapped beneath a community near a 4-acre sinkhole.

An unknown amount of gas is trapped below Bayou Corne. The water-bearing sands are under a layer of clay. John Boudreaux tells The Advocate there are worries the gas might build up pressure under that clay.

He says contractors began driving casing on Saturday for three vent wells to get a better idea about what is happening underground.

He said crews also have begun installing underground devices called geoprobes to monitor gas levels.

Bayou Corne’s 150 households have been evacuated since the sinkhole appeared Aug. 3. It is just off the edge of the Napoleonville Dome, a 1-mile-by-3-mile underground salt deposit.