(Salem, OR)  --  Environmental officials are working to evaluate the damage after a tanker truck tipped over on Highway 22, spilling thousands of gallons of fuel.  The Oregon Department of Environmental Quality says the truck was carrying two tanks of gasoline and diesel when it crashed roughly 70 miles east of Salem.  Officials say it appears at least some of the fuel seeped into the North Santiam River, with provides drinking water for Salem and other nearby cities.  Officials are still working to determine the extent of the spill.