A truck carrying more than 100,000 pounds of road-base oil rolled over on Interstate 84, spilling the gooey mess and closing the freeway’s westbound lanes for about eight hours.

A semi-tractor trailer truck loaded with the thick oil rolled Monday on the approach to the overpass, rupturing the tank.

A minivan following the tanker ran into the wreckage, according to Idaho State Police reports. The semi’s driver, Carol Eves-Schiess, 54, of Springville, Utah, was thrown from the cab and suffered a broken leg.

The van’s driver, Terry Lemmon of Hagerman, was wearing a seat belt and suffered bruises and cuts.

“It’s gunky,” said Idaho Transportation Department maintenance foreman Rod Draper, watching sheets of the oil slowly drip over the lip of a cleanup contractor’s loader bucket. “You can use solvents to clean it up, but then the solvent is a hazardous material.”