DETROIT — U.S. regulators earlier this year demanded improvements to the pipeline network that includes a segment that ruptured in southern Michigan, spilling hundreds of thousands of gallons of oil into the Kalamazoo River, according to a document released Saturday.
The Pipeline and Hazardous Materials Safety Administration, the U.S. Department of Transportation's regulatory arm, said it had summoned Enbridge Inc. executives in February to discuss problems with the 1,900-mile Lakehead system. Enbridge owns the pipeline that burst, sending oil into Talmadge Creek, which flows into the Kalamazoo River.
The pipeline safety agency informed Enbridge in January that it might have violated safety codes by improperly monitoring corrosion in the pipeline.
The Environmental Protection Agency estimates more than 1 million gallons of crude escaped, while the Canadian company puts the total at 820,000 gallons.
Meanwhile, company and government officials said Saturday they had located the pipeline fissure that caused the spill. Once removed, the section was expected to be taken to a National Transportation Safety Board lab for testing.
Also Saturday, EPA said it had rejected the company's long-range cleanup plan because of "deficiencies in content and technical details." It ordered Enbridge to submit a revised version by Monday.
And Saturday, U.S. Rep. Mark Schauer said the House Transportation and Infrastructure Committee had begun investigating the spill. "Enbridge needs to answer some tough questions about how this happened," the Michigan Democrat said.
According to a time line released Saturday by the Pipeline and Hazardous Materials Safety Administration, Enbridge last year discovered 250 imperfections with the line that eventually would rupture. The company immediately fixed 35 of them but is still working on the others.
The company requested permission this month to continue operating the pipe at lower pressure — which reduces the speed and volume of oil — for 2 1/2 years to allow time for repairs.
The Calgary, Alberta-based company shut down the pipeline Monday and had been looking for the break since.
Enbridge has declared the spill contained and says it is focusing solely on cleanup. The company said Saturday it was increasing the size of its team and the equipment at the site and that it has recovered more than 1.2 million gallons of combined water and oil. The mixture contained about 210,000 gallons of crude, the company said.