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Breaking News: Louisiana sinkhole alarms reported, seismic activity spikes
Louisiana sinkhole area residents reported to Assumption Parish officials hearing alarms over the weekend, but were told by officials that alarms are not going off. The alarm reports coincide with a spike in seismic activity, according to The University of Memphis Center for Earthquake Research and Information (CERI), and also might coincide with resumeddrilling into the sinkhole area after Tropical Storm Isaac left it.
Just hearing bells? Alarms heard might link to Bayou Corne sinkhole area seismic activity at Monitor #3 on Hwy. 70
According to the University of Memphis team's hellicorder charts of two of the six seismic monitors its Louisiana sinkhole team placed in the sinkhole area, monitors # 3 and # 9 at locations near Highway 70 in the Bayou Corne area, have recorded unusually higher seismic activity on September 2.
Those recordings are much higher than on previous days and at other locations that the team of scientists are monitoring in the area.
The University of Memphis, that has a contract with US Geological Survey to monitor seismic activity in the Bayou Corne sinkhole area, had recorded thousands of quakes in early August.
After locals reported to officials that they had heard alarms, officials responded to those reports in their blog post on Sunday:
"It has been brought to our attention that some people are speculating about alarms going off in the Bayou Corne area. Despite the fact that the OEP (Office of Emergency Preparedness) office is closed until Tuesday, calls have been made inquiring about such alarms, and it has been confirmed that alarms are NOT going off in the Bayou Corne area."
Hellicorder charts display each of the six monitors in the Bayou Corne sinkhole area, digitally simulating actual seismograms that are routinely recorded at CERI. The seismograms show a record of how the ground moved at a particular seismograph station in the Southeastern U.S. during a 24-hour period.
Bayou Corne resident and advocate Dennis Landry told the Examiner Monday on in a telephone interview, "After reports about hearing alarms in the area were made, a couple of locals went out to listen, but said that they didn't hear anything."
"We don't know who heard and reported those alarms," Landry said.
Drilling and seismic activity
The timing of the alarms reported and the recent seismic spikes might correlate with the resumed drilling of an observation well into the area.
Louisiana Commissioner of Conservation James Welsh stated Friday in a news release that Texas Brine’s rig operator, Riceland Drilling Co. of Lafayette, returned Thursday and resumed drilling shortly before noon Friday.
Before Hurricane Isaac hit the area, "The rig operator laid down the rig derrick, secured site equipment and evacuated the site on Monday, in anticipation of potential winds and flooding," Welsh reported. "Enforcement agents with the Office of Conservation monitored the shutdown of site operations, and continued to make site visits to assess the condition of the site before and after the storm's passage."
On Aug. 17, Assumption Parish officials issued a statement about vibrations that might be felt as drilling began at the sinkhole: "Texas Brine has informed us that the drill operation will start with driving 20 inch casing at the rig site for the next two days. The operations are expected to start between 9:00 p.m. and midnight tonight and will continue until completed. The casing driving may produce noises and vibrations."
At the time operations were suspended before Isaac, the company had drilled to approximately 600 feet and cemented the surface casing from 600 feet back to the surface to maintain well integrity through the Mississippi River Alluvial Aquifer. Blowout preventers and a diverter system had also already been installed.
At a local meeting with officials on Sunday in Bayou Corne, the reported alarms was not discussed, according to Landry.
On Aug. 9, a community explosion monitor alarm sounded in Assumption Parish's Bayou Corne sinkhole area. Officials said they suspected someone tampered with the monitor and that they were investigating the incident. The investigation final report has been unavailable to Deborah Dupré, who requested in an email the week of Aug. 13 that Assumption Parish officials provide her with a copy of that report.
Before the sinkhole rig operator's return to the site, "a Conservation agent inspecting the drill pad area noted the storm had caused a minor break in the small containment levee around the project's emergency pit," Jim Welsh reported. "The agent reported that nothing had been released from the pit, and the operator repaired the break Thursday."
"Well, I'm very concerned," a parish official told CBS last month, then referring to Lake Peigneur 80 miles west of the Bayou Corne sinkhole.
Lake Peigneur balances above a salt dome that collapsed in 1980 when a drilling rig punctured a protective layer in the salt mine wall, causing the entire lake, including a drilling rig, several larges barges, and large chunks of surrounding land to be sucked into the cavern.
"When you look at the scenario that happened in Lake Peigneur," the official said on CBS News, "the pronunciation of that I think is Lake Pen-oar, now you have a sink hole on top of a salt dome, with the suction and the pressure going down, I would certainly assume it's possible that it can penetrate the dome and then we definitely have an issue there."
At the time of publishing this article, officials at the Assumption Parish Police Jury and University of Memphis Center for Earthquake Research and Information Center have not returned Dupré's telephone calls and emails she sent to them Monday morning.
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