Local residents and the sheriff say the Department of Natural Resources "knew for months" that the Texas Brine well had integrity problems but didn't tell local authorities.

"DNR failed to report to anybody that this cavern could be the source of the bubbles," Landry said.

"I'm very upset about it. A lot of local residents are upset about it," he said. "I feel like I've been betrayed by the Louisiana Department of Natural Resources."

Said the sheriff, "DNR has lost all credibility with me."

Landowners near the sinkhole filed a lawsuit this week against the DNR and Texas Brine, claiming the drinking water has now been contaminated by a problem both the department and company allegedly knew about.