RICHLAND, Wash. (AP) — Trial in a federal court lawsuit over chemical vapors on the Hanford Nuclear Reservation has been delayed again.

A federal judge on Thursday pushed the trial date back three months to next Nov. 26. That's more than three years after the lawsuit was filed.

The Tri-City Herald reported the delay was requested by both plaintiffs and defendants in the lawsuit to give them more time to work toward a settlement agreement.

The state of Washington, Hanford Challenge and the pipefitters union Local 598 sued the U.S. Department of Energy and its tank farm contractor in 2015. They are seeking better protection for Hanford workers at risk of inhaling chemical vapors escaping from underground nuclear waste storage tanks.

The waste is left over from the production of plutonium for nuclear weapons.

___

Information from: Tri-City Herald, http://www.tri-cityherald.com