Last week, an underground tunnel storing radioactive waste at the Hanford nuclear facility in Washington state collapsed, leaving a gaping 400 square foot hole. The tunnel, made up of dirt and wood, finally gave in.
In 1991, Westinghouse Hanford Company requested Los Alamos Technical Associates, Inc. (LATA) to evaluate the structural integrity of PUREX Storage Tunnel #1, where the collapse occurred. While the 1991 study of the tunnel indicated a low probability of any degradation of the pressure-treated timber in the tunnel, the report noted that the “only structural degradation that is occurring is due to the continued exposure of the timbers to the high gamma radiation field in the tunnel.”
While the report noted the effect of this exposure was minor at the time, the strength of the timber walls in a 1980 evaluation was only 65.4% of its original strength. The study recommended that another test be conducted in 2001 by the United States Forest Product Laboratory to check the integrity of the tunnel’s wood beams.
There’s no evidence any further tests were carried out in 2001, or any other time since the 1991 recommendation. The United States Forest Product Laboratory and Department of Energy (DOE) did not respond to several requests for comment.
“How can waste be left in a tunnel? Whose idea was that?” asks Rod Ewing, a Stanford University nuclear security researcher. “I’ve been to Hanford many, many times for conferences and things like that, and I don’t recall anyone saying that there was waste in tunnels underground. I can’t imagine why that would be the case.”
The Department of Energy said there were no signs of a radioactive release and opted to fill the hole with 50 truckloads of dirt and a plastic cover.
While this seems like a short-term fix to a serious problem, the question remains, will this stop more collapses that could have far more dangerous impacts? According to Doug Shoop, manager of the Department of Energy Richland Operations Office, the answer is no.
“There is potential for more collapse,” says Shoop.
“One of the main problems at Hanford is that DOE is understaffed and overtasked,” Dr. Donald Alexander, a high-level DOE physical chemist working at Hanford, told me. “As such, we cannot conduct in-depth reviews of each of the individual systems in the facilities. Therefore there is a high likelihood that several systems will be found to be inoperable or not perform to expectations.”
Dr. Alexander says that Hanford could see an event comparable to the 1957 explosion, known as the Kyshtym disaster, at Russia’s Mayak nuclear facility. Kyshtym is considered the world’s third largest nuclear disaster after Chernobyl and Fukushima.
Considered Hanford’s”sister-facility,” Mayak also produced plutonium for nuclear bombs. At least 22 villages and 10,000 people were forced to evacuate when Mayak blew. According to one estimate by the Soviet Health Ministry in Chelyabinsk, the ultimate death toll caused by the Mayak explosion was 8,015 people over a 32 year period.
Hanford has total of 177 underground storage waste tanks, of which there are 149 that are single-shelled and considered leak-prone by the EPA.
“In the extreme,” says Dr. Alexander, “another Mayak-scale incident” could occur at Hanford.
Poor oversight and a culture of cutting-corners could well lead to a deadly explosion like the one feared by Dr. Alexander.
So, what’s the big deal?
Just another aging nuclear facility on the brink of disaster.