TRAVERSE CITY, Mich. (AP) -- Oil is expected to resume flowing early next week through an underground pipeline that ruptured nearly two months ago and spilled at least 820,000 gallons of crude oil into a southern Michigan waterway, the pipeline owner said Thursday.
Enbridge Inc. CEO Patrick Daniel said the operation is scheduled to begin Monday morning, though several conditions must be met before final approval is given. The company's restart plan won approval Wednesday from the federal Pipeline and Hazardous Materials Safety Administration, which oversees the nation's pipelines.
PHMSA spokesman Damon Hill said Thursday that Enbridge must inform emergency personnel and arrange for third-party observers and all necessary equipment to be on hand, along with an aerial patrol of the pipeline.
"The time involved in completing these requirements may keep PHMSA from authorizing a restart for Line 6B until early next week," Hill wrote in an e-mail to The Associated Press, saying he couldn't be more specific on the timing. "Enbridge must certify the completion of these activities and PHMSA will verify."
Enbridge's line 6B -- which runs from Griffith, Ind., to Sarnia, Ontario -- has been out of service since the leak was detected July 26. When the flow resumes, pressure in the 286-mile-long pipe will be 20 percent below normal, Daniel said.
"It is very significant to get this line back into service ... safely," he said, adding that the company will notify the public and emergency response agencies in the area over the next two days.
The company also will have to fix numerous defects in the line and replace a dented section running beneath the St. Clair River within a year, PHMSA said.
Daniel said those requirements will be met, and the new 3,800-foot segment under the St. Clair should be installed and operating by mid-2011.
U.S. Sen. Debbie Stabenow, a Michigan Democrat, said she was concerned about going ahead with the plan before the government investigation of the spill is finished.
"Restarting the pipeline without fully knowing the cause of the rupture will put families and communities across Michigan at risk," Stabenow said.
Enbridge, based in Calgary, Alberta, also will meet a Monday deadline set by the U.S. Environmental Protection Agency for completing the initial cleanup of the Kalamazoo River and nearby creeks and shorelines, Daniel said.
On Thursday, the EPA ordered the company to finish removing oil that has been found beneath the water's surface -- and contaminated sediments -- by Oct. 31. Other measures to restore the area to its pre-spill condition will continue into next year, said Mark Durno, the EPA's deputy incident commander.
Some plants along the Kalamazoo River will die this winter, said Mike Masterson, a section chief with the Michigan Department of Natural Resources and Environment. Experts will decide next spring where additional vegetation is needed, he said.
Enbridge also must submit a report on potential damage to drinking water supplies and take samples from wells within 200 feet of affected waterways, said Susan Hedman, the EPA's regional administrator.
Some oil in sensitive areas may be left to deteriorate naturally if removing it would cause additional damage, Hedman said.
About 11 million gallons of oily water have been removed from the river and creeks, and about 700,000 gallons of oil has been recovered through a separation process, Daniel said.