Update: National monument fire 90% contained near Rattlesnake Mountain on Hanford site

A wildfire that started at the Hanford site late Wednesday morning was 90% contained 24 hours later, according to U.S. Fish and Wildlife Service.

It had burned an estimated 570 acres.

The fire was in an area of the nuclear site once used as a security perimeter, and now called the Arid Lands Ecology Reserve, which is part of the Hanford Reach National Monument that is closed to the public.

The fire was not on land used for the nuclear reservation’s mission of plutonium production for the nation’s nuclear weapons program from World War II through the Cold War.

The fire burned in grass and brush between Highway 240, which borders the weapons production land, and Rattlesnake Mountain on the national monument and burned south of the Rattlesnake Barricade entrance to the production portion of the nuclear reservation on the other side of the highway.

The fire burned at the toe of Rattlesnake Mountain, not reaching the 1200 foot road, said Cory Thompson, duty officer for the fire for the U.S. Fish and Wildlife Service.

No cause of the fire has been determined but it may have started at one of the roads on the reserve, Thompson said.

Four planes helped fight the fire, including three that dropped water and one that provided aerial supervision flying above those dropping water, Thompson said.

The Hanford Fire Department initially responded with nine pieces of wildland fire equipment.

Two water tender trucks and a bulldozer from Department of Energy contractor Hanford Mission Integration Solutions also responded.

Tri-Cities area firefighting agencies also fought the fire.

U.S. Fish and Wildlife Service, which manages the DOE land in the national monument, assumed command of the fire Tuesday afternoon.

Firefighters are expected to remain at the fire for a couple more days.

This story was originally published June 12, 2024 at 7:01 PM.