The Washington State Patrol is investigating the dumping of approximately 300 gallons of what is labeled as concentrated apple juice near State Route 17 in Douglas County.
The incident happened just off the highway near milepost 133, and authorities are now seeking information from the public.
Troopers from the Okanogan area are on-site, and the Department of Ecology is en route to verify the substance.
Officials are working to determine the exact nature of the spill and any potential environmental impacts.
Anyone with information regarding the incident is asked to contact the Washington State Patrol.