LAPWAI, ID – The Nez Perce Tribe Department of Fisheries Resources Management and Water Resource Department say there has been a spill of hydraulic fluid/oil in the North Fork Clearwater in the area of Ahsahka Bridge and downstream. The oil is reportedly coming from the hydro plant which is operated by Idaho Department of Water Resources on the pipeline that supplies water to Dworshak and Clearwater Fish Hatcheries.
The spill was identified Wednesday morning at daylight. Staff at the hatcheries have notified the response groups and the situation is evolving. The hydro unit has been shut down. The estimated amount of fluid spilled is 50 gallons. There is oil in the rearing ponds at both facilities and in the North Fork of the Clearwater River, say officials. No fish mortalities have been reported. Hatchery staff are working to absorb and clean up the oil within the hatcheries and in the river near the Dworshak Hatchery intake pumps.
Tribal fishers along the shore of the North Fork Clearwater should use caution. Officials say rocks along the riverbank may be slippery.
The spill has been identified as Chevron Clarity Hydraulic Oil AW32l. The Safety Data Sheet (SDS) for Chevron Clarity Hydraulic Oil AW32 states that skin contact is not expected to cause prolonged or significant irritation, those impacted should wash exposed skin with soap and water after potential contact. The SDS also states that ingestion and eye exposure aren’t expected to be harmful.
Regarding the impact on fish, the SDS states that this oil is “not expected to be harmful to aquatic organisms.” Since oil is insoluble in water and does not mix into the water column, direct toxicity is minimal unless fish are in prolonged contact with an oil slick. Given that this spill occurred in the North Fork of the Clearwater River, much of the oil has likely moved downstream and dispersed, reducing long-term exposure in the immediate area.
“It sounds like booms have been deployed and are containing whatever is still present at this point. Unlike persistent organic pollutants like PCBs, PAHs, etc., which bioaccumulate over time, short-term exposure to a non-persistent petroleum-based oil in a high-flow river environment poses a very low risk for accumulation in fish tissue,” says a Nez Perce Tribe release.
