The source of a mysterious sheen on the Columbia River has been found, nearly 10 days after its initial discovery.
The Washington Department of Ecology released a statement Monday, saying leaking underground pipes caused a biodiesel spill near Wenatchee.
Rob Walls from the department’s response team says the size of the leak is unknown.
“You know, we need to kind of do a lot of calculations to figure out what exactly was released to the river," Walls said. "For me I would call this a moderate, moderate event, because there are so many unknowns still to find.”