Officials: Crude oil source may link sinkhole and failed cavern

Source: Governor's Office of Homeland Security and Emergency Preparedness
Source: Governor's Office of Homeland Security and Emergency Preparedness

Information from Department of Natural Resources:

BATON ROUGE, LA - Louisiana Commissioner of Conservation James Welsh said Wednesday that detailed, comparative analysis has revealed that the liquid hydrocarbon from the failed Texas Brine cavern and samples from the nearby sinkhole/slurry area strongly indicate that both are naturally occurring crude oil and not diesel – likely from the same underground source.

Experts theorized that early analysis of the substance coating the surface of the sinkhole/slurry area showed it could be a "diesel-range" hydrocarbon – meaning it contains some of the same hydrocarbons as refined diesel fuel; however, that classification has now been ruled out.

Welsh said that early analysis was primarily aimed at establishing potential toxic effects, and used the term "diesel-range" as a rough classification, with further analysis needed to determine the nature of the substance more precisely.

"Distinguishing between 'diesel fuel' and 'diesel-range crude oil' is critical to the effort to ensure public safety by determining the cause of the cavern failure and the sinkhole, and their possible link to each other and to the natural gas that has been found in the aquifer in the Bayou Corne area," Welsh said. "While our ongoing review of operational records on the Napoleonville Salt Dome has not shown one single underground source known to contain enough diesel fuel to cover the sinkhole/slurry area, an underground oil-and-gas formation could easily account for the amounts found on the sinkhole/slurry area surface and in the cavern."

Welsh said that better understanding of the source of the crude oil could also help better identify the source of the natural gas in the aquifer because oil and natural gas are often found together in productive formations.

Additionally, he noted that ongoing "fingerprint" analysis of natural gas samples from Bayou Corne-area bubbling sites has now ruled out the nearby Crosstex butane storage caverns and Acadian natural gas storage caverns as potential sources of the natural gas bubbling.

Welsh also said that as analysis of the failed cavern and sinkhole is ongoing, work has progressed on construction of the vent wells – with initial flaring of natural gas expected to begin by Friday.

"We discovered natural gas in both wells sites near the sinkhole and are now working as quickly as possible to remove it through these vent wells," Welsh said. "However, the initial analysis of the third well, sited on the west side of Bayou Corne, reveals that it does not have an accumulation of natural gas, though analysis will continue at that well as the work continues throughout the area to resolve the situation for the community."