Old well could be source of swamp bubbles
State and parish officials are investigating whether a well apparently overlooked in an initial check of abandoned wells a month ago may be the source of natural gas inexplicably bubbling up in two northern Assumption Parish bayous, parish officials said Tuesday.
The so-called “orphan” well is in wooded swamp about 1,000 feet from the main bubbling area at underwater pipeline crossings in Bayou Corne, parish officials say.
As of late Tuesday, there was still a lot of mystery surrounding the old well. Parish officials could not say who owned it, what kind of well it is or what type of gas is causing bubbles to emerge around the well.
“It’s going to take some investigation to see if it is the source,” said John Boudreaux, director of the parish Office of Homeland Security and Emergency Preparedness.
He said the well is on land but bubbles from releasing gas can been seen in a ditch near the well, and mud from underground appears to have been pushed up around the well.
The well, which is about 2,200 feet from the nearest residence, is below La. 70 South and between Bayou Corne and the Texas Brine Co. LLC facility to the east.
Boudreaux said the well appears at the surface as a 4.5-inch-diameter pipe sticking out of the ground about 5 feet high. Air tests around the well show the gas has reached 35 percent of what is called the lower explosive limit, he said.
The lower explosive limit, called the LEL, is the point at which an ignition risk exists in the immediate area around the well.
Boudreaux said the level around the well raises concerns that whatever is being released is flammable, though tests on the gas’s composition are pending.
Boudreaux has said that a lower explosive limit that reaches 60 percent could prompt evacuations.
Residents of Bayou Corne and neighboring communities have been rattled since late May by the bayou bubbles and by a series of contemporaneous, small earthquakes that have been recorded by the U.S. Geological Survey.
The unexplained occurrences have also prompted a response from a variety of state and local agencies.
The parish has established a command post in the area, and USGS is monitoring the tremors.
Meanwhile, the Louisiana Department of Environmental Quality has been testing air quality outside private residences since July 18 and is testing water quality. A civil support team with the National Guard is also testing gas releases, parish officials have said.
Louisiana Department of Natural Resources officials and others have asked for patience as they check oil, gas and brine production infrastructure in the area and the integrity of nearby salt dome caverns inside the Napoleonville Dome.
So far, firm answers for the cause of the bubbles or the quakes, and whether the bubbles are connected to earthquakes, have not emerged.
John Achee Jr., a community activist who has a camp and family acreage in Bayou Corne, said news Tuesday that a possible source for the bubbles had been discovered raised hopes at first. But he said some worry has also set in about what kind of well it could be.
“People are still frustrated,” Achee said. “That ain’t going to change until we find an answer. That only grows stronger the longer this takes.”
Boudreaux allowed the possibility that the well was a water well used in oil exploration — DNR maps show a few are in the area — and that the well might not be the source but rather could be a conduit for gas releasing from a different source.
Boudreaux said DNR is researching the well location and plans to hire a contractor to excavate the well, probably starting on Thursday, to try to learn more.
In contrast to the releases from the well, the gas bubble locations in Bayou Corne and nearby Grand Bayou have continued to have lower explosive limit percentages of zero or virtually zero and pose no explosive risk, according to parish and state officials.
They have also said tests have shown that the gas released in the bayous is natural gas, not swamp gas.
Officials with Boudreaux’s office, DEQ and DNR observed the bubbling at the well Monday night, a parish news release says.
Boudreaux said authorities had been notified after an employee of the landowner heard bubbling from the area but did not see the bubbling.
Boudreaux said the bubbling noise is not loud.
“You really have to listen for it. It does make a noise,” he said.
DNR officials did not return messages for comment Tuesday.
Residents who feel tremors can report them with an online form provided at the parish website http://assumptionla.com/bayoucorne.
Those without Internet access can call the parish OEP at (985) 369-7386.