An Oregon wood treater kept polluting a town’s water source with a now-banned chemical — but regulators didn’t stop it

After decades trapping crayfish in northwest Oregon, Mike Hailey could tell when something was wrong.

In the summer of 2023, Hailey noticed crayfish had disappeared downriver from a wood treatment facility in Sheridan operated by the Stella-Jones Corporation, a multinational Canadian company. Further up, his traps filled in an hour. But downstream, as the South Yamhill River flowed toward town, they were empty, his bait untouched.

“This concerns me,” Hailey wrote in a complaint to the Oregon Department of Environmental Quality on Aug. 22. “Is there something going on in the South Yamhill River that would be a contributing factor?”

Hailey never got an answer to his question. But both state and federal regulators knew something was wrong the summer he shared his concerns.

The wood treatm