THE SINKHOLE - THIS IS NOT GOOD

 

Texas Brine Co. LLC suspended cleanup work at a large sinkhole in northern Assumption Parish after the southwestern edge of the slurry area collapsed Thursday morning, company and parish officials said.

Two workers with Texas Brine’s cleanup contractor, Clean Harbors of Norwell, Mass., were rescued from their small aluminum boat by a co-worker in an airboat shortly before the workers’ boat sank into the sinkhole along with the collapsing earth, the officials said.

Assumption Parish Sheriff Mike Waguespack said the boat was tied to a leaning tree on the shoreline. The workers saw the tree begin to move and managed to get out the way, escaping with their equipment at about 8:30 a.m., the officials said.

Waguespack said an area of earth collapsed that extended from the shoreline to about 50 feet inland. The sheriff said bubbling in the sinkhole intensified after the collapse.

Texas Brine and the civil authorities expected the sinkhole to expand, but, despite their reassurances, I wonder about the unexpected that could happen.  I fully understand that the authorities don't wish to alarm people unnecessarily, but still...

In an earlier post on the sinkhole, one of my readers speculated that the butane stored in the salt cavern might be in barrels, but I see no mention of barrels thus far.

Crosstex also submitted a revised worst-case scenario analysis in its risk management plan Wednesday at the request of DEQ Secretary Peggy Hatch.

In a statement Thursday, DEQ officials noted that the cavern, which is a half-mile underground and far below the bottom of the sinkhole, cannot release its liquid butane contents without water being pumped into the cavern to push out the butane. The butane is also being held in the absence of oxygen. (My emphasis)

“While it is easy to simply convert the known quantity of butane into a blast scenario, that does not mean this scenario is possible,” DEQ officials said in a statement.

My inner pessimist which, though buried, occasionally rises and now thinks of oxygen somehow getting into the mix in one of those who-would-ever-have-expected...scenarios.  Surely my inner pessimist is way off base.

UPDATE: My inner pessimist is not the only one concerned.

Assumption Parish Sheriff Mike Waguespack said Thursday he is now concerned the sinkhole is close to a well containing 1.5 million barrels of liquid butane, a highly volatile liquid that turns into a highly flammable vapor upon release. A breach of that well, he said, could be catastrophic.

 

Map from International Business Times.

SINKHOLE, SALT CAVERN, BUTANE UNDER PRESSURE

The Louisiana Department of Environmental Quality has asked the operator of a salt cavern near a sinkhole in northern Assumption Parish to describe what would happen if all butane that could be held in the underground storage facility were released to the surface, state officials said Tuesday.

DEQ Secretary Peggy Hatch asked for the updated worst-case scenario from Crosstex Energy LP of Dallas by close of business Wednesday after reviewing the company’s current risk management plan for the cavern, state officials said in a news release.

The Crosstex salt cavern, which holds 940,000 barrels of liquid butane under pressure, is 1,600 feet from the sinkhole on the adjacent Texas Brine Co. LLC property south of La. 70 south.

DEQ says the Texas Brine is in compliance, but the what-if ramifications if the salt dome has failed are sobering, indeed.

DEQ officials said Tuesday there are “a lot of dynamic things” happening around the butane cavern, including expected well drilling, and community concerns have arisen.
....

DNR scientists suspect the Texas Brine cavern may have been carved too close to the edge of the Napoleonville Dome and failed, releasing its brine contents and causing the sinkhole.
....

DEQ officials said Crosstex’s updated plan submitted in January considers risks for butane, natural gas and other gases and suggests a full release might lead to windows being broken at two-thirds of mile. Piehler said two-thirds of a mile is close to the Bayou Corne community, which has about 150 residences, but does not actually include it.

Jill McMillan, spokeswoman for Crosstex said:

“Based on these findings to date, we believe our facilities have not been impacted by the slurry-filled sinkhole, and there has been no indication their integrity has been compromised,” she said in the email.

Let's hope and pray that none of the worst-case scenarios happen, nor a scenario that none of the experts have thought of, and we hear the lament, "Who would ever have expected...?"  That amount of butane under pressure sounds quite dangerous to me, and I hope the authorities are not playing down the seriousness of the situation as authorities are wont to do.

For those of you who may be concerned about us, we are about 30 miles away from the site and presumably safe.

Thanks to MM for his concern.  I planned to post on the situation yesterday but never got around to it.