NEW ORLEANS (AP) — A collapsed wall of an abandoned underground salt cavern where a Texas company had operated is being blamed with causing a sinkhole and contaminating an aquifer in a sparsely populated area of swampland west of New Orleans.
The Louisiana Office of Conservation said new data shows that a series of problems — natural gas bubbling up in local bayous and a growing sinkhole that's swallowed about 4 acres of swamp forest — are linked to the collapse of a side wall of an underground salt cavern that Houston-based Texas Brine Co. LLC operated. The company extracted brine and piped it to nearby petrochemical facilities.
Late Thursday, Conservation Commissioner James H. Welsh ordered Texas Brine to make sure the collapsed cavern does not worsen and to do more testing, monitoring and analysis to understand what is happening underground.
"We have a sense of what happened, now we're trying to figure out what is still happening," said Patrick Courreges, a spokesman for the Louisiana Department of Natural Resources.
In August, the sinkhole opened up near a community along Bayou Corne in Assumption Parish, about 60 miles west of New Orleans. Residents in the area had reported strange bubbling in their waterways and tremors before the sinkhole opened up. Officials then issued a voluntary evacuation order to about 350 people living near the sinkhole.
Extracting brine from salt domes is a common practice in Louisiana, where there are 75 active brine wells. Brine is used to make chlorine, an important building block for petrochemical and plastics manufacturers.
Sonny Cranch, a Texas Brine spokesman, said the company has not finished its own analysis of what happened but that it would comply with the Office of Conservation's order.
The company has acknowledged a relationship between the sinkhole, the breached cavern and gas and oil found in both. But the company has suggested geologic tremors in the area may have caused the cavern breach.
State officials say probes of the cavern and surrounding area reveal that a side wall of the cavern collapsed. When that happened, natural gas and crude oil that had been trapped underground began seeping to the surface, the state said.