Marshall County oil leak nearly twice original estimate

The amount of crude oil that leaked from a pipeline in Marshall County is nearly twice as much as originally believed.

Some 9,700 barrels of oil escaped into farmland near Amherst when the Keystone Pipeline broke the morning of Nov. 16. That total is according to Robynn Tysver, a spokeswoman with TransCanada, the owner of the line.

The original estimate was 5,000 barrels.

There are 42 gallons in a barrel of oil, so about 407,400 gallons leaked using the new, larger numberof barrels.

That new number would make the spill in Marshall County the seventh largest onshore oil or petroleum product spills since 2010, as reported to the U.S. Department of Transportation.

Repairs have since been made. TransCanada resumed using the pipeline 12 days after the leak.

“The remediation work on the property has been completed. We have replaced the last of the topsoil and have seeded the impacted area,” Tysver said in an email sent to the American News late Friday evening.

The final report on the Keystone leak is expected to be released in the next few weeks by the federal Pipeline and Hazardous Materials Safety Administration.

Brian Walsh, an environmental scientist manager for the South Dakota Department of Environment and Natural Resources, said the state received the corrective action order report about a week ago. He is in the process of reviewing the 4,000 pages to verify the data and make any necessary changes before the final report is published publicly.

The most recently updated pipeline safety administration report on the pipeline leak estimated that the incident has cost TransCanada $9.57 million.

A preliminary report indicated that the pipe might have been damaged during construction in 2008.

The Keystone Pipeline carries crude oil more than 2,600 miles from eastern Alberta, Canada, to Oklahoma and Illinois.

Follow @smarvel_AAN on Twitter.

Biggest spills

The spill of an estimated 407,400 gallons of crude oil discovered in November in Marshall County from TransCanada’s Keystone Pipeline would be one of the 10 largest onshore oil or petroleum product spills since 2010.

Here are the top 10 spills during that period as reported to the U.S. Department of Transportation. If TransCanada’s new estimate holds true, the Marshall spill would be the seventh-largest.

The list ranks them by size and includes the date, gallons spilled, commodity, company name, city or county and state of spill and estimated costs including property and environmental damages.

1. July 29, 2013: 865,200 gallons, crude oil, Tesoro High Plains Pipeline Co., MountRail County, N.D., $17.8 million.

2. July 25, 2010: 843,444 gallons, crude oil, Enbridge Energy, Marshall, Mich., $927 million.

3. Dec. 5, 2016: 529,830 gallons, crude oil, Belle Fourche Pipeline Co., Billings County, N.D., $11 million.

4. June 4, 2011: 513,618 gallons, crude oil, Enterprise Crude Pipeline LLC, Chico, Texas, $1.5 million.

5. Oct. 11, 2010: 428,400 gallons, crude oil, Centurion Pipeline LP, Levelland, Texas, $70,748.

6. Jan. 19, 2017: 420,378 gallons, crude oil, Tallgrass Pony Express Pipeline, Logan County, Colo., $345,554.

7. Nov. 16, 2017: 407,400 gallons, crude oil, TransCanada Corp, Marshall County, S.D., $9.7 million.

8. April 13, 2011: 378,000 gallons, gasoline, Marathon Pipe Line, Dansville, Mich., $38.7 million.

9. Dec. 8, 2014: 369,600 gallons, gasoline, Plantation Pipe Line Co., Belton, S.C., $4 million.

10. Aug. 29, 2016: 361,200 gallons, crude oil, Sunoco Pipeline LP, Sweetwater, Texas, $4 million.