Information from newly drilled monitoring wells provides guidance for action
BATON ROUGE – Louisiana Commissioner of Conservation James Welsh announced today that he has ordered all companies operating on the Napoleonville Salt Dome to immediately begin work to assess the presence of natural gas in both the ground water aquifer and the salt dome cap rock beneath their operations; capture, vent or flare any natural gas that is encountered; and analyze any potential impacts to ground water in the Mississippi River Alluvial Aquifer.
Welsh asked the Shaw Group [Shaw's ties to nuclear industry here and here] to oversee the evaluation of natural gas concentrations in the ground water aquifer and to oversee the removal of any natural gas found through venting or other means.
Welsh said he issued the order to dome operators as part of a formal Declaration of Emergency and Directive to ensure public safety following the Office of Conservation’s discovery of two shallow pockets of natural gas in an area between the western edge of the Napoleonville Salt Dome and the Bayou Corne community. A contractor hired by the Office of Conservation drilled monitoring wells to sample for natural gas, and encountered the natural gas pockets at a depth of less than 50 feet from surface on Thursday.
This discovery comes as Conservation staff analyzed new data from Texas Brine LLC’s report to the Office of Conservation. The data indicated pockets of natural gas within the Mississippi River Alluvial Aquifer and the cap rock above the salt dome. That data came after DNR ordered Texas Brine to evaluate belowground conditions. Part of Texas Brine’s effort to comply with that order included the drilling of a shallow well to house seismic equipment in addition to the deeper well intended to enter the abandoned salt cavern.
Texas Brine’s shallow seismic well, drilled to about 465 feet, encountered natural gas near the top of the ground water aquifer at about 120 feet deep, and again within the salt dome cap rock at about 420 feet deep.
“This is the reason that the Office of Conservation ordered Texas Brine to take steps to evaluate the belowground conditions near its operation and the reason we have hired contractors and negotiated with land owners to get observation wells drilled near the Bayou Corne community. This will help us gather information that gives a clearer understanding of potential threats to public safety and what the underlying causes are,” Welsh said. “This new data indicates the presence of natural gas in the aquifer and cap rock near the existing salt dome operations, and the Office of Conservation is ordering immediate action to assess that risk and take actions where necessary.”
Welsh said that, while the Office of Conservation had already begun the effort to assess the presence of natural gas nearer the Bayou Corne community by hiring two drilling contractors to drill wells for sampling and venting, he is actively seeking to accelerate those efforts with a solicitation this week to any companies with the necessary equipment to drill these water wells.
That solicitation, as well as the Shaw Group contract for overall evaluation and remediation of natural gas in the ground water aquifer in the area, followed Office of Conservation review of data from the most recent monitoring.