Kepone is the proprietary name for decachloroocta-hydro-1,3,4,-metheno-2H-cyclobuta[cd]-pentalene-2-one, a synthetic chlorinated insecticide. The drug was patented in the 1950s by Allied Chemical and introduced in 1958 as a virtually invincible compound to combat leaf-eating insects, ants, roaches, and fly larvae. Between 1966 and 1975, Allied Chemical, with contractor Life Sciences Products, produced Kepone at a small plant in Hopewell, Virginia, along the James River. At its highest output level, the factory produced 3,000 to 6,000 pounds of Kepone per day by operating day and night. The wastes were dumped directly into the James River. Local, state, and federal authorities overlooked safety regulations or made exceptions, in large part because chemical production was Hopewell's biggest industry.

The citizens of Hopewell discovered the effects of this dumping in 1975, when an employee of Life Sciences, who suffered from a peculiar case of uncontrollable shivering, was determined to have high levels of Kepone in his blood. Almost immediately, the plant was shut down. Studies were released demonstrating Kepone's negative effects on neurological and reproductive systems, as well as the liver, skin, and vision. Meanwhile, analysis showed that Kepone was found throughout the James, in its sediment, and all over Hopewell.

In December 1975, commercial and sport fishing were banned and a warning was issued to anyone who privately caught fish in the James River or any of its tributaries. Any fish with more than 0.1 parts per million Kepone was considered dangerous to human health. Eventually this level was raised to 0.3 parts per million, where it remains today. The fishing industry had disintegrated by the time the commercial fishing bans started to lift in May 1980. Even after that, Americans, wary of the Kepone scandal, refused to buy seafood from Virginia. Hundreds of fishermen went out of business. Allied Chemical and Life Sciences, meanwhile, were sued by former workers, residents, and fisherman and found liable for more than $200 million in damages.

Today, Hopewell and the James River have largely recovered from the Kepone scandal. The fishing bans have all been lifted and corrupted sediment has been covered by new sediment. The plant's toxic soil and residue were removed and buried in a salt mine.