A press release issued Thursday by the Louisiana Department of Natural Resources says based on samples taken from the sinkhole, Bayou Corne, and near the failed Napoleonville Salt Dome indicate Texas Brine's failed cavern is the likely source of the natural gas and crude oil that has been seeping into the area's water supply.
"We have been driven by scientific data in all of our efforts to determine the cause of the natural gas found in the aquifer, the formation of the sinkhole, and the presence of crud oil found on the surface of the sinkhole," says Commissioner of Conservation James Welsh in a prepared statement.
“Establishing how natural gas reached the aquifer and what caused the formation of the sinkhole was an important step in the process, but the work is not yet done. We will continue to hold Texas Brine accountable and ensure that this work is completed as quickly as possible, in a manner that protects their safety and the environment."
According to DNR's press release:
Welsh noted that, based on “fingerprint” analysis and other data, the source of the crude oil and natural gas that have been observed at the surface in the Bayou Corne area appears to be one or more naturally occurring oil and natural gas formations, and that the preponderance of scientific evidence indicates that the failure of the sidewall of the Texas Brine cavern provided a pathway up to the aquifer and the surface for oil and natural gas that had previously been confined thousands of feet below.
Texas Brine, according to Welsh's orders, must:
• Maintain stability of pressure in the failed cavern to prevent additional changes to the cavern or sinkhole due to pressure changes.
• Install monitoring wells in the Bayou Corne community to monitor water quality and pressures, as well as elevation benchmarks within the community for subsidence monitoring.
• Install pressure monitor at wellhead of the cavern re-entry well, designed to provide real-time data to parish emergency response agencies of any rapid pressure change.
• Upgrade and expand seismic monitoring array to cover a wider area and include real-time data processing and interpretation of micro-seismic data, with seismic data reported in real-time to parish emergency response agencies.
• Install continuous water level monitoring station at the sinkhole.
• Collect and interpret geophysical data to determine the exact structure of the zone of failure and its impact on the surface and subsurface.
An effort also is under way, according to DNR, to increase the number of "observation/vent wells" in the area to aid in the removal of the natural gas that has seeped into the aquifer near Bayou Corne.