BAYOU CORNE — It’s the fear of the unknown for Ginger and her husband Jarred Breaux. That is what is so unsettling about the natural gas bubbles coming up from nearby bayous and the unexplained tremors of the past 45 days or so in northern Assumption Parish.
Called by Bayou Corne residents like the Breauxs for response and action, parish officials have been monitoring the gas bubbles while state agencies investigate possible sources. And, U.S. Geological Survey researchers set up seismometers Thursday to better understand the earthquakes.
Jarred Breaux, 31, said he has hunted and fished the swamps just south of their home on Jambalaya Street off La. 70 South since he was a boy. He said he has seen what the couple calls “alligator bubbles” come up for the past 10 years near three gas pipeline crossings running along one another on Bayou Corne.
In recent weeks, Jarred Breaux said, the bubbles spots have increased in number.
“It ain’t one spot anymore,” he said.
Ginger Breaux, a 28-year-old teacher, said she began noticing vibrations in late May after school closed. On different occasions, she said, the tremors knocked askew a hanging picture frame, moved a sofa and put out a candle by shifting the pool of liquefied wax collected at the base of the wick.
“It’s nerve-wracking because we don’t know what it is,” Ginger Breaux said.
The gas releases continue not to pose a flammability risk and are not toxic, state and local officials said.
Researchers hope that by pinpointing the location of the small quakes — some were recorded by a USGS station in White Castle — they may be able to say if the quakes are linked to the gas releases. The first monitor set up detected seismic activity on Friday, parish officials said, though possibly not big enough to be felt.
The gas bubbling up from Bayou Corne and Grand Bayou were different sizes and had varying intensities last week as blue herons perched on cypress knees, fish jumped and dragonflies flitted over bubble areas, nature seemingly indifferent to the worries of mankind.
One small spot on Grand Bayou blurbed up slowly, quickly lifting and then closing a blanket of duckweed like a small underwater creature opening a green hatch for look at the surface.
The gas bubbles at the pipeline crossings on Bayou Corne are a different story. The 12 separate spots have varying intensities. The largest and first roils at the surface and is a bit bigger than a large crawfish pot.
Driving in a 22-foot metal hull boat Thursday that is used for twice daily monitoring, John Boudreaux, director of the parish Office of Homeland Security and Emergency Preparedness, said the largest spot’s location over the pipelines initially led him to suspect the lines were leaking.
The water is 5 feet deep and the lines are in 11 feet of mud under the water, he said.
But a battery of tests, including divers’ use of a jet of water to remove mud and find a leak, have shown otherwise and not provided a cause, Boudreaux and other officials have said.
Since that “jetting” occurred, Boudreaux said, the number of bubble locations near the pipelines has increased in number to the current 12.
Counting the 12 grouped together, there is a combined total of 18 locations on Grand Bayou and Bayou Corne. The closest location to homes is about a sixth-tenths of a mile away, state and local officials said.
The Louisiana Department of Natural Resources and other agencies have focused on the oil and gas infrastructure and brine operations in the area. The parish has about 680 miles of transmission lines alone, according to DNR.
But tests have not yet shown any of this infrastructure to be the source of the leaks.
Madhurendu Kumar, director of DNR’s Geological Oil and Gas Division in the Office of Conservation, raised a new prospect during a community meeting Thursday. Gas stored in pockets of a fault along the Napoleonville Dome could be being released naturally, he said.
Bayou Corne is about a mile from the northwestern edge of the salt dome.
Deep muds containing natural gas were drawn up as the salt dome was pushed to the surface in geologic history, Kumar said. The muds are closer to the surface now and tied into a system of fractures that can release gas intermittently, he said.
“So that is the situation. So we are investigating all the possibilities,” Kumar said.
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