(Reuters) - An underground leak of jet fuel in Parkland, Washington, prompted the shutdown of a pipeline owned by U.S. Oil & Refining Co, the state’s environmental agency said.

The volume of the spill on Wednesday from the McChord Pipeline, which was contained, has not been determined, and none of the leaked fuel has reached surface water in the area, the Washington Department of Ecology said in a statement.

“A contractor was doing some ... digging and hit the pipeline that goes from U.S. Oil & Refining Co. to McChord Air Force Base,” company spokeswoman Marcia E. Nielsen said in an email on Thursday.

U.S. Oil said a cleanup was under way and that it would continue to provide jet fuel to the Air Force base by truck until the pipeline is repaired.

The 14-1/4-mile-long (23-km-long) pipeline runs between U.S. Oil’s refinery in Tacoma and storage tanks on the base, according to the company’s website.