Preliminary Test Now Required For Fukushima Nuclear Cleanup
Not so fast with the Fukushima decommissioning, TEPCO. A Japanese government-affiliated agency (the Japan Nuclear Energy Safety Organization) has advised the Tokyo Electric Power Company that its proposed method of clearing Reactor Unit 4’s exposed cooling pool needs a test run before anyone commits to a full-scale plan. Japan Times reports that conducting and evaluating the test may add another two weeks to the cleanup schedule.
TEPCO had devised a plan to start removing fuel rods from the stricken reactor containment as early as Friday. Mirroring international fears about the situation and concerns that U.S. Energy Secretary Ernest Moniz expressed during his visit last Friday, the energy bureau has limited the utility’s program to one initial safety test, sources close to the matter told the Japan Times on Monday. Sea water corrosion, three explosions, fallen debris, likelihood of fuel rod breakage and uranium pellets escaping, and the possibility of rods colliding all increase the danger of further nuclear compromise at the unit.
“If any [rods] come into contact with each other or are exposed to air, gases with high levels of radiation will be released or, worse, there could be a catastrophic explosion,” Hong Kong’s South China Morning Post reported.
David Suzuki, an award-winning scientist at the University of Alberta, has called the Fukushima decommissioning “the most terrifying situation I can imagine…. I’ve seen a paper which says that if in fact the fourth plant goes under an earthquake and those rods are exposed, it’s bye-bye Japan, and everybody on the West Coast of North America should evacuate.”
As TEPCO has described it, the upcoming decommissioning trial involves transferring spent (used) fuel rods under water from the radioactive cooling pond of Unit 4 into a steel enclosure within a huge protective cement cask. A new crane has been built to make the transfer. It will also transport the cask into a larger pool, common to all four reactors, in a different building about 100 yards away. (For more, see the company’s online animation of the procedure.) This appears to be a combination of the spent fuel pond cooling-off method and the dry cask process Exelon introduced about two years ago at its Braidwood Nuclear Station about 60 miles southwest of Chicago.
TEPCO’s plan is designed to provide more stable, less exposed conditions for allowing the fuel to continue cooling until danger of a new chain reaction has passed. Unit 4 is the only one of four affected reactors that did not melt down during the crisis, but onsite explosions blew off its containment roof and part of the walls and affected the building’s stability.
“The agency has already inspected the equipment to be used in the operation on behalf of the Nuclear Regulation Authority,” the Times report said. “It has also urged TEPCO to have its work evaluated by a group of Japanese and overseas experts formed by the International Research Institute for Nuclear Decommissioning, a Tokyo-based organization founded by Japanese government agencies, nuclear facility manufacturers, and electric power companies.”
Former Japanese Ambassador to Switzerland Mitsuhei Murata wrote to U.S. President Barack Obama last week that “It is urgently needed to set up an international task force to assist Japan by deploying all possible means to reduce the risks of the imminent first unloading of spent fuel from unit 4.”
Kyodo News International commented on other issues at the plant: “Efforts continue to contain leaks of a massive amount of highly radioactive water accumulating at the plant as a result of water injections into the crippled Nos. 1 to 3 reactors. Underground water into the plant’s premises has been compounding the problem and leaky water storage tanks have added to fears of seawater contamination.”