A Dilbit Primer: How It’s Different from Conventional Oil, Lisa Song, Inside Climate News, June 26, 2012
“Bitumen extracted from tar sands has the consistency of peanut butter and must be diluted to flow through pipelines. And that’s just the beginning.
“When emergency responders rushed to Marshall, Mich. on July 26, 2010, they found that the Kalamazoo River had been blackened by more than one million gallons of oil. They didn’t discover until more than a week later that the ruptured pipeline had been carrying diluted bitumen, also known as dilbit, from Canada’s tar sands region. Cleaning it up would challenge them in ways they had never imagined. Instead of taking a couple of months, as they originally expected, nearly two years later the job still isn’t complete.
“Dilbit is harder to remove from waterways than the typical light crude oil—often called conventional crude—that has historically been used as an energy source.
“While most conventional oils float on water, much of the dilbit sank beneath the surface. Submerged oil is significantly harder to clean up than floating oil: A large amount of oil remains in the riverbed near Marshall, and the cleanup is expected to continue through the end of 2012.
“InsideClimate News spent seven months investigating what made the Marshall spill different from conventional oil spills. Part of the challenge was that there has been little scientific research on dilbit; most of the studies that have been done were conducted by industry and considered proprietary information…”
See also: The Dilbit Disaster: Inside The Biggest Oil Spill You’ve Never Heard Of, Part 1, Elizabeth McGowan and Lisa Song, Inside Climate News