Shortly after midnight on October 11, 2000, a coal sludge pond in Martin County, Kentucky, broke through an underground mine, propelling 306 million gallons of sludge down two tributaries of the Tug Fork River into the Big Sandy. The Martin County sludge spill killed all aquatic life along 30 miles of river, damaged municipal water systems, and caused millions of dollars in property damage. Appalshop filmmaker Robert Salyer follows the government agencies and community members through their clean up efforts and their attempts to understand the causes of a disaster 30 times larger than the Exxon Valdez oil spill. Filmed over four years, the documentary chronicles the aftermath of the disaster, the Mine Safety and Health Administration whistleblower case of Jack Spadaro, and the looming threat of coal sludge ponds throughout the Appalachian mountains.