A derailed Southern Pacific tanker car spilled as much as 19,000 gallons of a poisonous weedkiller into the Sacramento River in Northern California, forcing the evacuation of hundreds of residents, killing tens of thousands of fish and devastating the ecosystem along a 40-mile stretch of the stream, officials said yesterday.
The spill in southern Siskiyou County on Sunday night also forced the temporary closure of a 50-mile stretch of Interstate 5 and briefly engulfed the small city of Dunsmuir in a noxious cloud of gas.
At least two dozen people sought treatment at local hospitals, mostly for headaches, dizziness, nausea and eye irritation. By midnight, the toxic compound Vapam was expected to reach Lake Shasta, a key source of drinking water for millions of Californians.
Federal officials who maintain Shasta Dam said that the chemical would likely pose no threat to the state's water supply because it will be sufficiently diluted once it hits the reservoir, which currently holds 550 billion gallons of water.
Jeff McCracken, a spokesman for the U.S. Bureau of Reclamation, said that his agency would halt all releases of water from Shasta Reservoir if tests showed that there was serious contamination as a result of the spill.
Wildlife experts, meanwhile, were gravely concerned about the toll the chemical will take on the river's ecosystem, including a trout fishery that many anglers agree is the best in California.
Republican Assemblyman Stan Statham of Oak Run, who represents the area where the spill occurred, surveyed the river from the air and described the episode as "probably one of the worst ecological river spills ever on record in our north state."
"The chemical is killing 100 percent of the fish it is contacting as it moves from the site of the spill to Lake Shasta," said Tom Mullins, a spokesman for the state Office of Emergency Services. "The stream is obviously in extremely bad shape."
Paul Wertz, a spokesman for the state Department of Fish and Game, said that the spill "looks devastating" and "has the potential to wipe out a large portion of the fishery on the upper river, if not all of it."