Yesterday marked the 70th anniversary of the world’s first man-made controlled nuclear chain reaction in Chicago, December 2, 1942. To mark the occasion, I took part in a podcast hosted by noted nuclear pundit Rod Adams which included several other prominent bloggers from the nuclear education, research and industry communities. It was an upbeat, sometimes humorous discussion between many of the most prominent nuclear bloggers on the internet. Here’s the link…

Now for today’s updates….

  • A Fukui University researcher has discovered that human cells have “immunity to radiation under certain conditions”. Fukui Associate Professor in Radiobiology Hideki Matsumoto has learned that low-to-moderate radiation exposures used in emergency medical treatments cause a “radiation adaptive response” similar to what happens when vaccines are used to treat diseases. This cellular phenomenon was first noticed in the 1980s, but researchers could not pinpoint what caused the counter-intuitive effect. It turns out that when cells are irradiated, they produce a “nitric oxide” compound that repairs damage as fast as it occurs. Matsumoto also found there is a “bystander response” with nearby cells which are not irradiated, making them increase their radiation-immune capability in concert with the irradiated cells. The first observation of the bystander response in human cells occurred in 2001, but Matsumoto’s is the first research that has established why it happens. It seems the adaptive response is very high at exposures below 100 millisieverts. This suggests that low level radiation exposure is much, much less risky than existing estimates make it seem. Surprisingly, at 10 sievert exposure, which theoretically should kill all cells, Hideki found that 1% survived! As the dose increases, the beneficial effect also amplifies but with less and less effectiveness as exposure intensifies. At “lethal” exposure levels, the beneficial effect gets overwhelmed to the point that 99% of the cells die. In a related discovery, Matsumoto observed that mice injected with nitric oxide and then exposed to high radiation levels showed a doubling of survival rate. (Fukui News)
  • While it is unlikely that it will end the wild speculations about Fukushima Daiichi unit #4’s reactor building integrity, Tepco’s latest data on the structure should end it. Tepco’s lengthy press handout was released on Saturday. Here’s the link…
  • New hypothetical exposure-reduction simulations for nuclear accidents have been posted by Japan’s Nuclear Regulatory Authority. A flawed model released last month was riddled with technical problems. The new estimates now include factors not previously used; for example, the effects of meteorology, topography and the protective effects of pre-exposure Iodine tablet ingestion. The NRA says that all people within 5 kilometers of a nuke should be evacuated before any radioactive releases happen. People within 5-10 kilometers should take shelter in concrete buildings until the radiological cloud passes, then evacuate to beyond 30 kilometers if necessary. Adults and children between 10 and 30 kilometers should take Iodine tablets before the release begins and stay indoors until the radiation cloud passes. The NRA stresses the simulation assumes a worst-case accident and the worst-possible weather conditions that would cause the highest unprotected exposures. The NRA and Japan’s Atomic Energy Agency say this should be invaluable to local governments drawing up emergency evacuation plans. The model is based on a 1,100 MWe nuke and radioactive releases that start 24-27 hours after the accident initiates. (NHK World; Mainichi Shimbun)
  • Two new antinuclear lawsuits have been filed relative to the Oi nuclear station. The first suit comes from a group of 1,100 people want the two currently-operating plants at Oi to be shut down immediately because they will cause “irrevocable damage” if an accident occurs. They believe the faults under the sea-water intakes at Oi are seismically active would cause a nuclear disaster if they move. The plaintiffs include many Fukui Prefecture residents, but also persons living in 17 other prefectures. In addition to demanding immediate shutdown, the plaintiffs each seek 10,000 yen in damages from Kansai Electric and the government because operating the two units at Oi threatens their legal right to live safely. The second suit includes 154 Fukui Prefecture residents who say Tokyo and Kansai Electric illegally started the two units at Oi before their safety had yet to be guaranteed. The group wants the operating units at Oi shuttered immediately. The suit states that last year’s Fukushima accident proves “the totally unacceptable risks of nuclear power plants”. (Kyodo News Service)
  • Tepco’s recent release of more Fukushima accident video footage continues to reveal disturbing news. In one case, Plant Manager Yoshida pleads with then-PM Kan’s office to let him use fire engine pumps to spray water into the slowly-evaporating unit #4 spent fuel pool. A member of the PM’s staff at Tepco/Tokyo rejected Yoshida’s request. Yoshida continued his plea, so Kan Aide Goshi Hosono told him, “We’ll continue efforts to reduce such risks as much as possible.” Hosono said the government would spray water from Self-Defense Force helicopters. “We made the decision after consulting with Prime Minister Naoto Kan and others in an emergency meeting,” Hosono told Yoshida. On March 17, the helicopters showed up and dropped water from huge suspended buckets. At first, F. Daiichi staff is heard to say they were relieved that the #4 SFP was getting water, but this was soon replaced with woe, “The water hasn’t reached the target,” one suddenly-irritated employee says, “It’s just like a mist.” Frustrated, Yoshida told the PM-staffer at Tepco/Tokyo that their plan was flawed and, “We’ll die if it explodes.” In another section of the video, Yoshida tells Tepco/Tokyo on March 18th that his staff at F. Daiichi needs to be immediately relieved by new people because they were worn out from working long hours and many were reaching their 200 millisievert exposure limit. Yoshida says, “…they’ve been going to the site a number of times. They pour water, make checks and add oil periodically. I cannot make them be exposed to even more radiation.” Completely frustrated with Tepco’s lack of progress on his demands for staff relief, Yoshida barked, “If we do the work under a plan with no feasibility, it will end in failure. We cannot do it unless we have thorough help.” Tepco/Tokyo responded that they were doing all they could to get Yoshida more people. (Mainichi Shimbun; Asahi Shimbun)
  • A new news media poll shows that incumbent Prime Minister Noda’s approval rate is at an all-time low and the nuclear energy issue ranks third among the Japanese public. When asked what matters most in the December 16th election, 31% cited the state of Japan’s economy, 22% said it was social security reform and 13% replied it was energy policies including nuclear power generation. Within the issue of energy policy, 11% want nuclear energy abolished immediately, 26% want it ended in 10 years, and another 12% want “no-nukes” by 2040. However, 35% said more time should be spent before making a firm decision on nuclear power’s future in Japan. With respect to Noda’s popularity, his cabinet received but a 21% approval rating – the lowest since he took office in the summer of 2011. Only 20% say he should be the next Prime Minister, while 25% favored LDP head Shinzo Abe, and 49% favored neither candidate. (NHK World)
  • Japan Future Party leader Yukiko Kada says her party will not allow any currently idled nukes to restart. Kada stated, “It’s impossible under the current circumstances.” Then, in apparent contradiction to herself, she had said she would accept reactivation of idled nuclear reactors if the Nuclear Regulation Authority guarantees their safety and the government deems it necessary. Kada also described her party’s policy of “departure from nuclear power” in 10 years as its “goal.” “We’d like to achieve that as early as possible, but electric power system reform and other measures are needed before then. Considering these matters, we set a realistic goal of achieving an end to nuclear power in 10 years from now.”