Two companies that lost the use of natural gas pipelines after the formation of a large sinkhole in northern Assumption Parish last summer are moving toward permanent reroutes around the swampland slurry hole.
Acadian Gas Pipeline System and Crosstex Energy LP have applications pending with the state Office of Conservation to construct new sections of pipeline south and east of the sinkhole after recent public hearings on the proposals, said Patrick Courreges, spokesman for the state Department of Natural Resources.
Crosstex Energy, which is based in Dallas, has issued news releases estimating it is losing $250,000 to $300,000 per month while the section of its 36-inch pipeline next to the sinkhole is out of service.
Acadian lost two 20-inch lines that are an important link in the company’s 705-mile Louisiana network. The loss left the system “bifurcated” between southern and northern segments, said Rick Rainey, spokesman for Enterprise Products Partners LP of Houston, the corporate parent of Acadian Gas. The loss also shut in two natural gas production wells in Assumption.
The out-of-service lines represent some of the spillover effects of the sinkhole that formed between the Grand Bayou and Bayou Corne communities sometime between nightfall Aug. 2 and the morning of Aug. 3. The sinkhole is believed to be linked to the failure of a nearby Texas Brine Co. LLC salt cavern.
Residents of the two communities were ordered on Aug. 3 to evacuate their homes and camps. The date of the evacuees’ return is uncertain. State highway officials also are studying an alternative route for La. 70 South to bypass the sinkhole area, though they say La. 70 is not threatened.
The sinkhole, now with an 8.5-acre surface area, swallowed up swampland next to a pipeline corridor and converted it into a briney lake, quickly threatening the pipelines and bending a 400-foot section of Crosstex’s 36-inch line in the corridor.
One day after the sinkhole was discovered, La. 70 South was shut for about 24 hours until Crosstex’s pipeline, the two pipelines owned by Acadian and a lateral line owned by Florida Gas Transmission Co. LLC were depressurized under orders issued by the Office of Conservation.
Since then, the sinkhole has increased in size and further undermined the pipeline route, parish officials have said.
The reviews by the Office of Conservation’s Pipeline Division, which regulates the construction, operation and safety of pipelines in Louisiana, is a key regulatory hurdle for the replacement lines proposed in the swamps north of Lake Verret in Louisiana’s Coastal Zone.
Public comments have not been submitted or raised in recent hearings on either of the projects.
Acadian and Crosstex also have filed for permits with the U.S. Army Corps of Engineers and DNR’s Office of Coastal Management, agency personnel said.
Crosstex applied with the Office of Conservation last month for the previously announced 36-inch, $20 million to $25 million replacement line, due for construction by this summer.
The proposed 4.74-mile pipeline section will roughly follow an L-shaped route around the sinkhole and the Grand Bayou area until it ties into the company’s existing pipeline north of La. 70, Crosstex’s application says. The line will be able to handle 1 billion cubic feet of gas per day.
Dubbed the Chico Pipeline Relocation Project, Acadian’s single 20-inch replacement line will extend 4.42 miles along a U-shaped route east of the sinkhole before rejoining Acadian’s system, according to a company application submitted shortly after Jan. 1.
Rainey said Acadian Gas was able to install a temporary fix to meet customer demands but a permanent solution is needed to ensure that the company can continue to supply customers during the winter months and to restart production from the wells.
“What we’re proposing now, the reroute around that area, should take care of our needs for the long term,” Rainey said.
With a capacity of 1.5 billion cubic feet of gas per day, the northern part of Acadian’s system reaches into the energy-rich Haynesville Shale gas play to the south. This Haynesville Extension starts in Assumption Parish and extends to Red River Parish some 270 miles away, Acadian’s application says.
The southern half of Acadian’s system links with gas-reliant petrochemical industries and the Henry Hub, a key North American distribution point in Erath where gas spot prices and futures contracts are set.
Acadian officials provided testimony on their plan during a hearing Thursday before Brent Campbell, Conservation Pipeline Division director, at the LaSalle Building in Baton Rouge.
Keith Masterson, Acadian’s vice president for Louisiana pipelines, said the pipeline route was chosen to maximize its ability to parallel existing rights of way and avoid construction in the area.
During a separate hearing Thursday, Masterson described plans to abandon a combined 2.1 miles of pipeline. The company wants to remove a combined 1,350 feet of line near the sinkhole and leave the remaining 9,700 feet of pipeline in the ground.