Emergency crews on June 4, 2016, found an oil sheen on the bank of the Columbia River near the site of an oil train derailment and spill in Mosier, Oregon, the day prior.
Amelia Templeton / OPB
When a Union Pacific oil train derailed and burst into fire in Mosier, Oregon, in June, the initial damage was in plain view, as dark smoke billowed into the sky.
Now OPB has learned about invisible damage: elevated concentrations of benzene and other volatile organic compounds in groundwater near the derailment site.
Bob Schwarz, a project manager with Oregon's Department of Environmental Quality, says Mosier's drinking water is not at risk, as the closest groundwater drinking wells are uphill from where oil spilled. But he is concerned about wildlife in a nearby wetland. He says cleanup is needed.
"The concentration that we found (of benzene) was 1,800 parts per billion, which is approximately ten times higher than a screening level for what would concern us for animals living in a wetland," Schwarz told OPB All Things Considered host Kate Davidson.
LISTEN to the full interview with Bob Schwarz.
