Discuss as:

Massive Louisiana sinkhole prompts drilling to find source

The sinkhole is swallowing up large cypress trees and other vegetation. NBC's Brian Williams reports.

The Texas-based owner of an abandoned cavern that officials think is the cause of 420-foot deep sinkhole in Louisiana received approval to drill a new well that may shed light on the source of the gaping hole, NBC station NEWS33 in Baton Rouge reported

Located in the Assumption Parish, about 50 miles south of Baton Rouge, the hole has swallowed up trees and prompted a mandatory evacuation for nearby residents. Structural damage within the Napoleonville salt dome is believed to be its cause.


Texas Brine Co. got approval to drill the test well to determine the cavern's structural status and what pressures, brine or natural gas, it contains. The company faced $5,000 a day in fines if it didn't submit a permit request for the well by Monday. 

 Stay informed with the latest headlines; sign up for our newsletter

"Texas Brine has met the requirement set for the company to have that permit submitted, but that is not the end of their responsibility," Louisiana Department of Natural Resources Secretary Stephen Chustz told the station. 

Company president Mark Cartwright told state officials that drilling equipment will start arriving late Wednesday or early Thursday, with drilling to begin a few days later. It will take 40 days to get into the cavern.

The company was also informed that its original permit for the cavern closest to the sinkhole requires it assist evacuees. Texas Brine will set up a relief fund for people who were forced to leave their home after Gov. Bobby Jindal declared a state of emergency in the parish.

John Boudreaux, director of the parish's Office of Homeland Security and Emergency Preparedness, told The Associated Press that around half of those told to leave their homes have actually left their homes. 

The sinkhole, in a heavily wooded area 200 feet from the cavern, was discovered Aug. 3 following several months of natural gas bubbles coming up from bayous in the area.

The hole has since grown to about 370 feet wide and 420 feet deep by state estimates, though an official with the state Department of Environmental Quality told The Advocate some sections of the hole are only 50 feet deep.

Water samples taken last week showed no detectable levels of naturally occurring radioactive material on the hole’s surface. Additional samples were taken, but results won’t be ready until later in the week. 

Watch US News videos on NBCNews.com

The AP reported that Texas Brine will be responsible for progress reports of the drilling.

"There are no further regulatory approvals Texas Brine needs at this point," Chustz said. "From here on, their timetable is only limited by their decisions, but we will be monitoring progress to ensure that they expedite the drilling of that well, while maintaining a safe operation."

More content from NBCNews.com:

Follow US News from NBCNews.com on Twitter and Facebook