For the past few days, I have been blogging about the tunnel collapse that happened Tuesday at the Hanford Nuclear Reservation in south central Washington State near the Plutonium Uranium Extraction Plant (PUREX). As the days pass, more information is being released so I am continuing to blog about the accident.
"The infrastructure built to temporarily store radioactive waste is now more than a half-century old," said Maia Bellon, director of the state ecology department. The three hundred and sixty foot railway tunnel was built in 1956 and was used between 1956 and 1988 to move spent nuclear fuel from Hanford Reactors to the PUREX so that uranium and plutonium could be extracted for the manufacture of nuclear weapons. It is estimated that seventy thousand tons of spent uranium fuel rods were moved through the two underground tunnels. After the end of the Cold War, the tunnels were used to store the radioactive railway cars that had been used to move the spent fuel. Other equipment and materials that had been contaminated were also stored in the tunnel. The tunnel contains about seven hundred and eighty cubic yards of radioactive waste.
It turns out that although the collapse of the tunnel was discovered on Tuesday, it could have happened up to four days before it was discovered. There are no regularly scheduled inspections of the underground tunnels. The nuclear waste manager for the Washington state Department of Ecology, which helps regulate the Hanford site, said "It's not acceptable that the hole could have been open for four days." Washington state officials demanded that the DoE “immediately assess the integrity of the Hanford tunnels.”
The dirt that fell into the tunnel when the ceiling collapsed apparently prevented the release of any of the radioactive material in the tunnel because the Hanford authorities claim that no radiation has been detected around the hole. Fifty four truck loads of dirt were poured into the hole to fill it.
In 2015, the U.S. DoE commissioned a report on the integrity of the tunnels. The report said that the steel, concrete and wood used to construct the tunnels had been weakened by exposure to intense radiation and that the tunnels could be collapsed by earthquakes.
Rick Perry, the new Director of the U.S. Department of Energy, said that filling the hole "was accomplished swiftly and safely to help prevent any further complications. Our next step is to identify and implement longer-term measures to further reduce risks.”
The Yakima Indians were moved off the land where the Hanford Nuclear Reservation is located which had been their reservation by treaty. Although they moved, they were given the right to monitor the Hanford Nuclear Reservation environment. The Yakima Tribe has released a statement that says that they had warned the DoE for several years that the tunnels were unsafe. "No preventative action was taken," the tribe said in a statement. The tribe also said that the railroad tunnels should be completely cleaned out long before the new 2042 deadline that has been granted to the DoE.
