Book excerpt: InsideClimate News won the 2013 Pulitzer Prize in national reporting for this four-part narrative and six follow-up reports into an oil spill most Americans have never heard of. More than 1 million gallons of oil spilled into the Kalamazoo River in July 2010, triggering the most expensive cleanup in U.S. history -- more than 3/4 of a billion dollars -- and after almost two years the cleanup still isn't finished. Why not? Because the underground pipeline that ruptured was carrying diluted bitumen, or dilbit, the dirtiest, stickiest oil used today. It's the same kind of oil that the controversial Keystone XL pipeline could someday carry across the nation's largest drinking water aquifer. Written as a narrative, this page-turner takes an inside look at what happened to two families, a community, unprepared agencies and an inept company during an environmental disaster involving a new kind of oil few people know much about.