Enbridge Says Pipeline Pressure Tests Show No Leaks
Enbridge Inc., which carries most of the oil imported to the U.S. from Canada, said no leaks were detected during pressure tests on a 13-mile segment of pipeline in Michigan that spilled oil last month.
The tests lasted eight hours and were completed late yesterday, Jennifer Varey, a company spokeswoman, said in an e- mail.
Enbridge’s 6B pipeline shut July 26 after rupturing and leaking 19,500 barrels of oil. Fuel from the line, operated by Enbridge Energy Partners LP, poured into the Tallmadge Creek and entered the Kalamazoo River, forcing residents to evacuate and coating birds, muskrats and turtles in an oily residue.
The pipeline transports crude from Griffith, Indiana, to Sarnia, Ontario. Refiners it serves, including BP Plc, were forced to cut processing rates or seek alternative sources of fuel because of insufficient volumes.
Enbridge said it has submitted a second pipeline startup plan to the Department of Transportation’s Pipeline Hazardous Materials Safety Administration that stipulates Line 6B will be operated at 80 percent of the operational pressure it ran at at prior to the rupture.
“The proposed lower-than-normal operating pressures will be less than 50 percent of the yield strength of the line pipe and thus provides a significant margin of safety upon proposed restart,” Varey said.
Dents in the Line
The company is also continuing, and in some cases accelerating, planned digs along the pipeline to inspect areas that have anomalies or certain “characteristics” detailed by the safety administration, Varey said. The agency asked that four areas be inspected and the company checked six, Varey said.
Dents have been indentified on Line 6B, including one located at mile marker 710.74, Varey said.
An in-line inspection recorded minor metal loss at the site, leading to the area being excavated on Dec. 13, 2009. As the feature met company maintenance standards, the pipe was recoated and no further action was taken, she said.
Another dent on Line 6B was confirmed at mile marker 751.22, where the pipeline crosses the St. Clair River.
While the likelihood of a leak is “remote, Enbridge has a plan under way to replace or repair this site as soon as feasible,” Varey said.
The dent was spotted last year and various investigations that included an underwater inspection concluded that the dent is “a smooth one without evidence of corrosion or sharp features,” she said.
Line Restart
Enbridge has worked with the administration’s Office of Pipeline Safety for months, providing engineering assessments and plans for repairs or replacements on its lines, Varey said. Operational pressure in the areas on the line identified as having dents has been reduced, she said.
It may take months “if not years” for the Department of Transportation to authorize the restart of Enbridge’s Line 6B, the Michigan Messenger reported, citing John Porcari, the department’s deputy undersecretary.
Porcari, speaking to residents at a meeting last week in Michigan’s Calhoun County, the site of the spill, said a plan to restart the pipeline hasn’t yet been agreed.
“Safety is our number one priority,” Julia Piscitelli, a spokeswoman for the Pipeline Hazardous Materials Safety Administration, said in an e-mail. Listening to the public’s concerns about the incident was among the steps the department and the pipeline safety administration were taking during a review of Enbridge’s operations, she said.
The administration’s engineers are reviewing safety data, testing results and reports and there will be no decisions until this is completed, Piscitelli said.
To contact the reporter on this story: Aaron Clark in New York at aclark27@bloomberg.net
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