Cleanup efforts continue in Montana where an estimated 1,000 barrels of oil have spilled into the Yellowstone River and traveled about 100 miles. The spill occurred when a pipeline burst near the town of Laurel and spilled into the Yellowstone. The town is down river from Yellowstone National Park.

“We do not know the root cause. This is a very unusual event,” said ExxonMobil Pipeline President Gary Pruessing during a report on the "PBS NewsHour." “Obviously we had a lot of oil enter the water very quickly and whatever it is, it is something that is very unusual for us. It is not something we have our hands around yet.”

Nearly 300 people are reported to be involved with the cleanup effort, which includes vacuum tankers and nearly 2,500 absorbent pads to soak up the crude from the water and riverbanks. And while the response is said to have begun just minutes after the spill occurred, this rupture may not have been a complete surprise. “The U.S. Department of Transportation, which overseas pipelines, recently notified ExxonMobil of seven potential safety violations along the pipe” reported Hari Sreenivasan for PBS. In fact, as has been pointed out a few times in the last year, problems with pipelines are becoming less surprising in the Untied States.

Recent pipeline problems

About a year ago, an estimated 800,000 gallons of oil poured into the Kalamazoo River in Michigan. Months later, 600,000 gallons of Canadian crude oil found its way into a retention pound in the Chicago suburb of Romeoville, Ill. These spills gave the industry one black eye in 2010, and a series of explosions that year left the American pipeline industry with more wounds.

Between January 2010 and February 2011, there were nine major pipeline explosions that resulted in 18 deaths, 13 injuries and 85 destroyed homes in the United States. Here’s the list of those accidents:

Jan. 5, 2010 in Jackson, Miss.

Owner: Gulf South

Deaths: 0; Injures: 0

Jan. 6, 2010 at Barksdale Air Force Base

Bossier City, La.

Owner: Private developers

Deaths: 1; Injuries: 0

June 7, 2010 in Johnson County, Texas

Owner: Enterprise Products Partners LP

Deaths: 1; Injuries: 8

June 29, 2010 in Pocasset, Okla.

Owner: Enogex LLC, a subsidiary of Oklahoma Gas and Electric Co.

Deaths: 0; Injuries: 3

Sept. 9, 2010 in San Bruno, Calif.

Owner: Pacific Gas & Electric

Deaths: 8; Injuries:

38 homes destroyed

Feb. 8, 2011 in Houston, Texas

Owner: Enterprise Products

Deaths: 1; Injuries: 0

Feb. 9, 2011 in Allentown, Pa.

Natural gas pipeline

Owner: N/A

Deaths: 5; Injuries: 0

47 homes damaged

Feb. 10, 2011 in Hanoverton, Ohio

Owner: El Paso Corp.

(Tennessee Gas Pipeline)

Deaths: 0; Injuries 0

Many accidents, many causes

Wikipedia has a thorough and well-sourced list of pipeline accidents, which includes the weekend incident in the Yellowstone River. As for the cause of these accidents, according to the Pipeline and Hazardous Materials Safety Administration, "Over the period encompassing 1990 through 2009, excavation damage is the leading cause of all pipeline incidents (causing 1,404 reportable incidents). The other top four causes are corrosion (causing 1,012 reportable incidents); material/weld/equipment failure (causing 914 reportable incidents); natural force damage (causing 428 reportable incidents); and incorrect operation of the pipeline (causing 343 incidents).”

Pipelines are everywhere

All of these incidents have happened throughout the United States, which as you can see in the map posted below, is covered in pipelines. Of particular note is the number of pipelines in the Great Lakes and the Gulf Coast regions.

Pipelines are an often under-reported portion of this nation’s energy and infrastructure debate, but it’s not because there isn’t plenty to talk about.

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