A semi-tractor trailer crash south of Colfax spilled an estimated 6,000 gallons of fuel Sunday, with some of the liquid leaking into Spring Flat Creek.

A truck with two trailers transporting fuel was driving southbound on U.S. Highway 195, 3 miles south of Colfax, around 9 p.m. Sunday. A cat ran into the road, and when the driver swerved to miss the animal, he lost control of the vehicle, according to a Washington State Patrol news release.

Trooper Ryan Senger said the second trailer flipped on its side and dumped a “significant amount” of fuel on the ground. He said it was more than the Washington State Patrol typically sees in terms of spills.

The trailer held a mixed load of fuel, and an estimated 4,000 gallons of diesel and 2,000 gallons of gasoline were lost during the incident, said Ty Keltner, communications manager for the State of Washington Department of Ecology. The agency is still working on measuring the exact amount of fuel that was spilled, but Keltner said the trailer holds a total of about 6,000 gallons, which is where they got their estimate.

The road was blocked off for about six hours and reopened at 3 a.m. Monday while officers assessed the damage and clean up crews arrived, said Senger. The driver was not hurt during the crash.

Senger said when there’s a spill of more than 50 gallons of fuel, WSP’s policy is to call the Department of Ecology to handle cleanup. The department hired a cleanup contractor that worked to recover fuel from the roadway and shoulder that was impacted by the incident, Keltner said.

Some spilled fuel leaked into Spring Flat Creek, Keltner said, and traveled a couple 100 yards downstream. Cleanup crews put an absorbent boom in the creek to create a barrier so the fuel couldn’t go farther. Keltner added crews hadn’t seen any migrating fuel farther south into the South Fork area.

Keltner said crews are still in the process of cleaning up the spill and they don’t have an exact time frame on when it will be completed. The department will assess the area and possibly excavate soil to make sure fuel hasn’t soaked into the ground.

Pearce can be reached at epearce@dnews.com or on Twitter @Emily_A_Pearce.