ST. PAUL - A November pipeline leak in rural South Dakota was nearly double in size than initially estimated.
According to a report on the Nasdaq website, the Keystone pipeline leaked about 9,700 barrels - or more than 407,000 gallons - of crude oil on Nov. 16 in Marshall County, up from initial reports of about 5,000 barrels. An investigation by pipeline owner TransCanada Corp and the federal Pipeline and Hazardous Materials Safety Administration found the rupture may have been caused by a concrete weight placed on the pipeline to hold the line in place near Amherst, S.D., about 130 miles southwest of Fargo.
The increased estimate makes the Marshall County spill one of the largest inland oil spills this decade. The same pipeline had a reported spill of 17,000 gallons in southeastern South Dakota credited to a bad weld in April 2016.
TransCanada reopened the line less than two weeks after the spill was reported, and company officials say cleanup efforts have been completed.
Attempts to reach TransCanada officials for comment went unreturned as of Monday afternoon, April 9.
The Keystone pipeline crosses into the United States from Manitoba, carrying Alberta oil southeast through North Dakota, South Dakota, Nebraska, Kansas and Missouri to Patoka, Ill., with a daily capacity of 590,000 barrels.