Exxon's Tar Sands Spill in Mayflower, AR: decided to power-wash diluted bitumen spilled in other areas to a wetlands area, via storm drains. Via Tar Sands Blockade.
Exxon Mobil Corp was working on Friday to remove the ruptured section of its Arkansas tar sands pipeline. Spokeswoman Kim Jordan said the length of the portion being removed from the Pegasus pipeline that ruptured two weeks ago would be determined once excavation to reach it had finished. However, Arkansas Attorney General Dustin McDaniel, who launched an investigation into the tar sands spill, said earlier this week that the rupture was more than 22 feet long and two inches wide:
So far, crews have recovered about 28,200 barrels of oily water and about 2,000 cubic yards of oiled soil and debris, according to a statement from ExxonMobil and local officials.
"We still do not know how much oil was released. We still do not know the exact makeup of the crude itself, of the chemical solvents used in the transportation process," McDaniel said. "
Lisa Song of InsideClimate News reports that the 22 foot rupture is nearly 4 times the size of the pipeline tear that sent more than one million gallons of Canadian dilbit into Michigan's Kalamazoo River in 2010, the worst accident of its kind in U.S. history:
The size and speed of the release through a long opening, thin as a mail slot, shines a spotlight on just how quickly oil pipeline accidents can turn into catastrophes. Between 200,000 and 420,000 gallons of heavy oil spewed out of the 65-year-old pipeline without warning on March 29, Good Friday afternoon, forcing the evacuation of 22 suburban homes.
Few Americans realize how much pressure is needed to operate a pipeline like the Pegasus, which moves more than 90,000 barrels a day of crude across four states, from Illinois to Texas. That's almost four million gallons of heavy oil being pushed over an 850-mile distance in a single day.
"People just don't gather how high these things can go," said Richard Kuprewicz, president of the pipeline consulting firm Accufacts Inc. "For the average person, they're just exotic pressures." But if pipeline operators drop their guard, he said, pipelines "can be highly destructive."
However, the fact that the Pegasus ruptured while running below maximum pressure "is not good," Kuprewicz said, because it means something was wrong with the pipeline's integrity management. Pipelines are supposed to be safe even if they operate at slightly above the maximum operating pressure, he said, so the Pegasus line "failed at a negative safety margin."
Recently obtained police transcripts show Exxon employees arrived on the scene in Mayflower an hour after the emergency was first reported by a resident dialing 911, and raise questions over exactly when Exxon became aware of the problem with the Pegasus pipeline.