Wednesday, April 27, 2011
Severe storms and tornadoes moving through the U.S. Southeast dealt a severe blow to the Tennessee Valley Authority on Wednesday, causing three nuclear reactors in Alabama to shut and knocking out 11 high-voltage power lines, the utility and regulators said.
All three units at TVA's 3,274-megawatt Browns Ferry nuclear plant in Alabama tripped about 5:30 EDT (2230 GMT) after losing outside power to the plant, a spokesman for the U.S. Nuclear Regulatory Commission said.
A TVA spokeswoman said the station's backup power systems, including diesel generators, started and operated as designed. External power was restored quickly to the plant but diesel generators remained running Wednesday evening, she said.
The Browns Ferry units are among 23 U.S. reactors that are similar in design to the crippled Fukushima Daiichi nuclear plant in Japan where backup generators were swept away in the tsunami that followed the massive earthquake on March 11.
The News-Courrier reported on April 12th that - like the Japanese reactors - the Alabama reactors shut down by tornadoes store a lot of radioactive spent fuel rods in an unprotected fashion:
At Browns Ferry, a plant with the same design as Fukushima-Dai-ichi in Japan, more than 1,415 metric tons of spent fuel and rods lie in three pools on a massive concrete pad above the plant’s three reactors.
All that encloses the pools is a heavy garage like metal roof and walls.
In contrast, reports on the amount of fresh and spent fuel together at all 6 Fukushima reactors is somewhere between 1,760 and 4,277 metric tons. In other words, when the fuel within the reactors is included, Browns Ferry may have almost as much radioactive fuel in its 3 reactors as are contained in all Fukushima's 6 reactors.
Moreover, the Browns Ferry plants are only built to withstand a 6.0 earthquake, even though the nearby New Madrid Fault could potentially cause a bigger earthquake. As the Huntsville Times wrote in a recent editorial:
Browns Ferry is built along the New Madrid fault and thus designed to withstand some degree of an earthquake. A tornado or a ravaging flood could just as easily be like the tsunami that unleashed the final blow.
Energy officials should re-evaluate nuclear plant designs and build in plenty of redundancies for worst-case scenarios.
Moreover, as Reuters noted recently:
Internal Nuclear Regulatory Commission e-mails and memos obtained by the Union of Concerned Scientists questioned the adequacy of the back-up plans to keep reactor cooling systems running if off-site power were lost for an extended period.
"While the NRC and the nuclear industry have been reassuring Americans that there is nothing to worry about -- that we can do a better job dealing with a nuclear disaster like the one that just happened in Japan -- it turns out that privately NRC senior analysts are not so sure" ....And Browns Ferry almost melted down in 1975.
Thankfully, there haven't been any reports of radiation leakage, and - since the diesel generators are working - there shouldn't be any problems in the near future.
But this is yet another reminder that many nuclear power plants are built with outdated designs and maintained in an unsafe, penny-pinching manner, and are very vulnerable to natural disasters or mischief.
Will we allow a nuclear black swan to happen in America ... which could be even worse than Japan?
Or will we be smart enough to tackle this problem now, while we still can?