Possible oil leak into Snake River near Kahlotus being investigated

Oil may have leaked at Lower Monumental Lock Dam on the Snake River near Kahlotus, according to the Army Corps of Engineers.

No oil sheen has been observed in the river downstream, but hydroelectric generator unit No. 2 was shut down after a leak was suspected on Thursday, according to the Corps.

An investigation is underway after maintenance workers detected a discrepancy in the mass balance of turbine oil at the dam’s powerhouse, possibly caused by a leak.

Because all six hydroelectric generator units are interconnected, determining the amount of oil lost can be difficult, said Don Redman, environmental compliance coordinator for the Corps’ Walla Walla District.

“If we confirm there is a leak, the unit will remain out of service until we can un-water it to conduct repairs,” Redman said.

This story was originally published August 5, 2017 at 2:29 PM with the headline "Possible oil leak into Snake River near Kahlotus being investigated."