Tempers flared Tuesday evening at a meeting in the rural Louisiana town of Pierre Part as the slurry churned in an Assumption Parish swamp, but everyone in attendance was told there was no danger of a natural gas or any other kind of explosion.
Last Friday a sinkhole appeared in swampland in an area that several natural gas pipelines pass by. The sinkhole was at least 372-feet wide and 381-feet deep, according to press reports, and has devoured cypress trees and forced the evacuation of 150 homes in the area. Facilities of Florida Gas Transmission (FGT), Enterprise Products Partners LP's Acadian Gas Pipeline LLC, Crosstex Energy and a gas storage facility have been affected (see Daily GPI, Aug. 7).
Chevron Corp.'s Bridgeline Holdings declared a force majeure at its natural gas storage cavern near Napoleonville, LA, due to the sinkhole. A Chevron Pipeline Co. spokesman told Reuters the company would draw down contents of the NS1 cavern as a precaution. There was no indication that gas was leaking from the facility.
Bridgeline asked customers to cut nominations of gas into the cavern and begin reducing their inventory to 40% of contracted amounts. The company said it owns three salt dome storage caverns with combined working gas capacity of 12.7 Bcf and maximum withdrawal of 1.1 Bcf/d.
Crosstex said it isolated and shut in a portion of its pipeline near the slurry area.
"The shut-in will impact approximately 150 MMcf/d of supply to the river markets," Crosstex spokesperson Jill McMillan said Wednesday. "We have notified our customers, and they've made arrangements to secure supply to avoid disruptions in this area. At this time, we do not know how long the pipeline will be shut in, but we're continuing to monitor the situation and hope to have it resolved soon. We're still assessing the financial impact of the reduced throughput and potential repair but do not expect it to be significant."
In a notice to customers, FGT said its Chacahoula and Napoleonville laterals are out of service.
"Florida Gas is working with the state of Louisiana as they investigate a sinkhole and its impact in the Assumption Parish. Accordingly, FGT has taken the Chacahoula and Napoleonville laterals out of service," the pipeline said. Until further notice, points unavailable for nominations beginning Wednesday were: "DRN 266472 Napoleonville Storage Rec; DRN 266493 Napoleonville Storage Del; DRN 105026 Acadian Assumption Interconnect; DRN 27588 Apache North Chacahoula."
An Enterprise spokesman said Monday Acadian had developed a workaround to avoid shutting in gas because of the sinkhole.
The Associated Press (AP) reported that air, water and sediment samples taken by the Louisiana Department of Environmental Quality indicated that there was no concern about a potential explosion or air pollution. The Louisiana Department of Natural Resources is the lead agency on the case; a spokesperson there did not respond to a request for comment.
Gas bubbles have been seen in recent weeks in the area, which is near an underground salt dome on land owned by Houston-based Texas Brine Co. LLC. Brine production from the salt dome was stopped in 2009 and the cavern was plugged and abandoned, AP reported. A fault in the salt dome is suspected of being the source of the bubbling.
©Copyright 2012 Intelligence Press Inc. All rights reserved. The preceding news report may not be republished or redistributed, in whole or in part, in any form, without prior written consent of Intelligence Press, Inc.