Appomattox pipeline in final stages of testing

By Carrie J. Sidener

Published: December 4, 2008

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The natural gas pipeline that exploded just north of Appomattox in September is in the final stages of testing and the company that runs it hopes to restore operation soon.

Williams Gas Co. began filling the repaired pipeline with highly pressurized water this week to test for problems before going to a federal regulatory agency for approval to put the line back in service, said Christopher Stockton, the company’s spokesman.

“The hydrostatic testing involves pressure testing the pipe with water far above its normal operating pressure,” he said Thursday. “In this case, the hydrotest pressure is about 1,100 (pounds per square inch). The maximum operating pressure on (the line) is about 800 psi.”

The pipeline is one of three that run side by side through Appomattox, bringing natural gas from the Gulf of Mexico to New York. It was shut down after it ruptured in September, sparking an explosion and fireball that leveled two homes and injured five people.

The pressure on the remaining two lines was significantly reduced while workers inspected them for damage. Last month, Williams brought one pipeline back into full service at 800 psi and hopes to increase pressure on the third by early next year.

Workers have replaced about 2,300 feet of pipe on the line that ruptured, called the B line.

Stockton said that is much more than otherwise would have been replaced, if the line was in operation. Crews used an inline inspection tool to detect areas that need attention.

“Our people are working very hard to expedite repairs to B line so that we can provide service to customers during this winter heating season,” he said.

“That means that instead of performing lengthy analysis to determine if a small section of line needs to be repaired and what type of repair may be necessary, we have instead elected to just cut out and replace long sections of pipe — far more than is necessary.”

The process is faster and further ensures the safety of the line, he said.

The hydrostatic testing is expected to finish next week. Then Williams will return to the U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration for approval to start flowing gas in the line.

“Once we receive their approval, we will gradually increase the pressure on B line to the normal level of 800 pounds per square inch,” he said. “We will conduct another public meeting to inform residents prior to B line being restored to full service.”

That pipeline, which crosses Virginia 26 just north of the town of Appomattox, failed before 8 a.m. on Sept. 14, a Sunday. The natural gas it released blew into a fireball that scorched an area 1,125 feet in diameter, according to preliminary findings in the federal investigation.

Early findings into the cause of the failure showed some metal loss at the explosion site, according to a federal report.

The natural gas pipeline that runs through Appomattox is part of the Transco line, which extends from the Gulf of Mexico to New York, including 858 miles in Virginia.