December 7, 2015

Dec 7, 2015 | Fukushima Accident Updates

  • Fukushima Cesium in the Pacific Ocean continues to be at safe levels. Woods Hole Oceanographic has released its latest data, and Ken Buesseler says tracking the plume is not difficult given modern, sensitive technology. If Cesium-137 is found by itself, then there can be no Fukushima contamination. If Cs-134 is also detectible, then it is due to Fukushima contamination. The highest Fukushima concentration in the most recent sampling is 1,600 miles west of San Francisco, at 11 Becquerels per ton of seawater. A Becquerel is one radioactive emission per second. This is 50% higher than the few locations along the Pacific coastline with the Cs-134 marker, but 10 times less than maximum levels found following post-WWII nuclear weapon’s tests. Further, it is 500 times lower than US drinking water limits. Though quite harmless, Buesseler says these detectible levels do have scientific value, “…these long-lived radioisotopes will serve as markers for years to come for scientists studying ocean currents and mixing in coastal and offshore waters.” On another note, Buesseler still believes that analytically-significant amounts of contamination are still being released to the sea by F. Daiichi. http://www.whoi.edu/news-release/fukushima-higher-levels-offshore
  • Fukushima student’s radiation exposures are the same as with other parts of the world. Five Fukushima high school students wore dosimeters for two weeks during the last half of 2014. 216 other students around the world – including six from elsewhere in Japan – did the same thing. The Fukushima students found that their exposures were about the same as the rest. One student says, “We would be glad if we could contribute to restoring confidence and rebuilding our reputation by letting people around the world know about the research results.” In an important relatyed note, it was found that student’s exposures in Belarus were also the same as the rest of the cohort. The student’s group thesis has been published in the Nov. 27 edition of the British Journal of Radiological Protection. http://www.fukushimaminponews.com/news.html?id=599 — http://iopscience.iop.org/article/10.1088/0952-4746/36/1/49 (British Journal link)
  • A Minamisoma Hospital study finds evacuee mortality was higher than non-evacuees. The death rate of nursing home evacuees was 2.68 times greater during the first year after the accident for evacuees, and 1.68 times greater for non-evacuees. The Minamisoma City mortality rate was compared to that of Soma, a city that is external of, but adjacent to the exclusion zone. The study also compared the mortality rate to the five years before the accident. Overall, elderly evacuees have had a death rate 1.86 times worse than elderly non-evacuees. But, looking at the mortality rates before and after evacuation for nursing homes themselves, the increase jumps to 3.37 times higher. Most importantly, those evacuated to facilities prepared to handle them showed no change in before-and-after rates of mortality. http://www.fukushimaminponews.com/news.html?id=601
  • Exclusion zone cows are tested for internal Cesium levels. The screening covers more than 120 cows in Okuma and Namie. Blood has been taken from each of the bovines and is being analyzed. The testing was done by the Society for Animal Refugee & Environment post-Nuclear Disaster, including veterinarians from from Iwate and Kitasato Universities. In addition to finding internal Cesium levels, the blood will be used for DNA testing. http://mainichi.jp/english/articles/20151207/p2a/00m/0na/019000c
  • The NRA comes under fire for incorrectly located BWR cabling. Japan’s upgraded nuclear regulations call for safety and safety-related power cabling to be separate from non-safety cables. Recently, Tepco informed the Nuclear Regulation Authority that cable trays under the floor of the control rooms at the seven-unit Kashiwazaki-Kariwa station are not properly separated. Subsequently, the NRA is being criticized for failing to conduct cabling inspections on the PWR units recently restarted and the others that have passed pre-operational screenings. While it seems to be a problem with BWR plants, the NRA says they “…can’t deny the possibility that other cables are mixed at pressurized-water reactors…” http://www.japantimes.co.jp/news/2015/12/06/national/nra-fails-to-conduct-on-site-checks-for-nuclear-plant-cables/#.VmQ_dJDosdV
  • Tokyo is called to give detailed public explanations of the need to build rural radioactive waste disposal facilities. Of the six prefectures charged with designating the sites, only Fukushima has stepped up and done it. The Yomiuri Shimbun says Fukushima Prefecture agreed because of a concerted effort on the part of the government to correctly inform elected officials and residents of everything associated with the issue. The criterion for public exposure from a disposal site is less than one millisievert per year. The nation’s largest newspaper concludes, “It is important to present correct, easy-to-understand information about radiation to local communities and win their understanding.” http://www.the-japan-news.com/news/article/0002610008