Atmos Technologies, an environmental services firm that helps control odors and dusts from landfills, has been identified as responsible for a toxic industrial spill into West Chester's Goose Creek. The incident occurred when chlorinated water from a tank at Atmos was released to a containment area mixed with a manufactured product called Long Duration Foam AC-645, which then leaked out of an outfall pipe. The liquid substance killed fish and polluted the water. No further fish deaths have been reported.