From: Inside Climate News
by Lisa Song
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.
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.