Texas Brine Co. is asking the Louisiana Office of Conservation to allow it to stop $875 evacuation assistance checks the company pays weekly to a few remaining residents and property owners in Bayou Corne.

Texas Brine has been making the payments at a total cost of nearly $12 million since Aug. 17, 2012, two weeks after the sinkhole appeared near the Bayou Corne community in Assumption Parish and forced a mandatory evacuation order still http://theadvocate.com/news/11010067-123/evacuation-order-lifted-in-small">largely in place.

Texas Brine attorney Troy Charpentier said the company recently made its case in a hearing at the state Department of Natural Resources that methane and stability conditions around the sinkhole have improved greatly and merit an end to the checks.

“We think we’ve proved neither the subsidence nor the gas pose any risk to the residences,” Charpentier said.

Office of Conservation scientists believe years of salt dome mining by the Houston company triggered formation of the sinkhole when mining got too close to the outer face of the dome, a large, solid, underground salt deposit. A breach opened in the hollow cavern created by years of past mining, and surrounding sediments filled the void.

The sinkhole’s formation also cracked open natural deposits of methane gas that posed an explosion risk to homes if the invisible and odorless gas built up inside or under the homes, the scientists said.

Under pressure from Gov. Bobby Jindal in 2013 to allow people who wanted to leave to be made whole, Texas Brine directly bought out 65 property owners and, more recently, bought out another 87 in a $48.1 million federal class-action settlement.

Charpentier said the few remaining weekly checks go to residents who continue to live in eight homes in Bayou Corne and to five landowners who were excluded from the class-action.

Residents who continued to collect evacuation assistance checks through the end of 2014 — the checks were retroactive to the start of the evacuation on Aug. 3, 2012 — took in about $112,000 per family.

Donaldsonville attorney Sidney Marchand III, who attended last month’s hearing at DNR, represents some of the families who remain in Bayou Corne and who have their own pending damages lawsuit against Texas Brine.

He said his clients oppose ending the weekly checks.

“The payments were started when the evacuation order was issued, and it’s still in effect, and they feel subject to the evacuation order, they have to be ready to evacuate, and nothing has changed. The payments should continue,” Marchand said.

Residents who took home buyouts from Texas Brine continued to receive their evacuation assistance payments until sales closed.

“Equal treatment is a factor,” Marchand said of his clients, who aren’t seeking home buyouts but have damage claims against Texas Brine.

With exception of one property in bankruptcy, buyouts through the class-action suit were completed by Jan. 31, said Sonny Cranch, Texas Brine spokesman.

Underpinning Texas Brine’s bid to end the weekly checks is its assessment of conditions in and around the sinkhole. Both the threat of gas and the sinkhole’s instability were factors in the evacuation order that came the same day the sinkhole was discovered, Aug. 3, 2012, parish officials have said.

Under the terms of a 1982 salt dome drilling permit with the Office of Conservation, Texas Brine must provide assistance to residents required to evacuate “if the area of collapse appears to threaten any residents. ”

Charpentier said the company’s experts and officials believe the 31-acre sinkhole is not a threat to homes. They pointed out that the breached cavern, whose once-great empty space drove the sinkhole’s formation, has been completely filled with surrounding sediments. The sinkhole is now only finding its final, natural shape along its edges, they claim.

Meanwhile, gas removal is winding down, and methane has not been measured in homes over the past two years, Charpentier said.

Methane gas still bubbles in area bayous, however, and tremors still periodically intensify and rattle around the sinkhole and in the nearby dome.

Bruce Martin, Texas Brine vice president of operations, said the bubble sites are greatly diminished and the tremors are not as severe as they had been previously.

The mandatory evacuation remains in place over Bayou Corne but has been reduced a notch to “voluntary” in nearby Grand Bayou while authorities seek to verify Texas Brine’s claims that the gas risk there has been mitigated. Parish officials have said they expect Texas Brine to submit data soon that could result in a similar voluntary order for the northern half of Bayou Corne.

Patrick Courreges, DNR spokesman, said Friday that the Office of Conservation, which is part of DNR and oversees salt dome mining, is evaluating the request and has 30 days from the Jan. 28 hearing to make a decision.

Follow David J. Mitchell on Twitter @NewsieDave.