SPOKANE, Wash. (AP) – Workers at the Hanford Nuclear Reservation in Washington state have finished stabilizing a partially-collapsed tunnel containing radioactive wastes left over from the production of plutonium for nuclear weapons.
The U.S. Department of Energy said Tuesday the tunnel was filled with more than 4,400 cubic yards of grout intended to prevent any additional collapse.
The tunnel partially collapsed earlier this year, prompting a brief alarm at the site that required some 3,000 workers to shelter in place. No one was injured.
Since early October, crews worked mostly at night to inject the grout, which is intended to reduce the risk of further collapse.
Hanford is located near Richland and was created during the Manhattan Project in World War II. It made most of the plutonium for the nation’s nuclear stockpile.