- A leak has been discovered coming from F. Daiichi unit #1 primary containment (PCV). The location has been identified by robotic inspection inside the donut-shaped suppression chamber (torus) room. The outflow is coming from a pipe attached to a “metal bellows joint” on the PCV wall. Some officials feel the leak may have been caused by accelerated corrosion due to the use of seawater to cool the core in March, 2011. It is a source of water pooled in the bottom of the Torus room, but there may well be more. It is critical to find all leakage points coming out of the inner containment structure and plug them so that the PCV can be filled with water. This will greatly lower the radiation field inside the reactor building and facilitate the removal of melted fuel. Previously, a robot found a leak coming from the unit #3 PCV. Unit #2 will be robotically investigated to find leaks out of its PCV. NHK World; Water leak detected at No. 1 reactor; May 28, 2014 — http://english.kyodonews.jp/news/2014/05/292793.html
- Tokyo has nominated two replacement Nuclear Regulation Authority Commissioners. The first is Tokyo University Professor Satoru Tanaka. He is former president of the Atomic Energy Society of Japan and touted as a nuclear engineering expert. The second is Tohoku University Professor of Geology Akira Ishiwatari. If confirmed, they will replace incumbent commissioners Kunihiko Shimizu and Kenzo Oshima. Neither incumbent has a background in nuclear engineering and/or plant operations. Thus, the addition of Tanaka to the commission will improve the agency’s overall level of nuclear expertise. However, antinuclear voices in Japan say the action is an attempt to remove opponents to the restarting of the country’s reactors. Hajime Matsukubo, spokesman for the anti-nuclear Citizen’s Nuclear Information Centre, said, “The personnel change is a blatant attempt to prompt resumption of nuclear plants.” His remark is due to seismologist Shimizu’s being replaced, who has been the strongest opponent of restarts based on his personal opinions relative to geologic anomalies. http://jen.jiji.com/jc/eng?g=eco&k=2014052700553 — http://jen.jiji.com/jc/eng?g=eco&k=2014052700553 — http://www.japantoday.com/category/national/view/govt-to-replace-anti-nuclear-members-on-industry-regulator
- In a hallmark decision, Shimane Prefecture has inked an evacuation accord with two neighboring prefectures. The plans are due to the NRA ruling to prepare evacuation of everyone within 30 kilometers of a nuke in the event of a worst-possible accident. There are nearly 400,000 people living within the 30 km zone around the Shimane nuke station owned by Chukogu Electric. Co. The Prefecture itself cannot accommodate all of them, so the local government asked neighboring Hiroshima and Okayama Prefectures for assistance. Both have agreed. This marks the first-such nuclear evacuation agreement between neighboring prefectures. http://english.kyodonews.jp/news/2014/05/292699.html (Comment – It is important to note that one of the neighboring signatories is Hiroshima Prefecture, home to the atomic bombing of its capitol city in August, 1945. This update blog has previously noted that there is virtually no antinuclear power plant sentiment in Hiroshima, and is perhaps the prefecture with the smallest radiophobic demographic in Japan. Hopefully, Hiroshima Prefecture’s pact with Shimane will promote other prefectures across Japan to follow suit.)
- Kansai Electric Co. might restart the Oi nukes despite the recent Fukui court order to not resume operations. The company has appealed the Fukui ruling to the Nagoya high court, insisting that both Oi units are safe to operate. Kansai President Makoto Yagi said they will probably start Shimane units #3 and #4 provided they pass all regulatory requirements and receive permission from the local communities before the high court hands down a decision on the appeal. http://www.japantimes.co.jp/news/2014/05/27/national/utility-may-restart-oi-reactors-high-court-ruling/#.U4XSmaNOUdV
- Radiophobia has struck Ibaraki Prefecture, roughly 100 kilometers due-south of F. Daiichi. A portion of Hitachi Seaside Park has been closed due to higher-than-natural-background radiation levels. Tokyo estimates that Japan’s natural background is 0.23 microsieverts per hour. Three park locations in surrounding woods and open fields have registered 0.70 µSv/hr. Although these levels are in no way health-threatening, the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) has roped-off the areas as a precaution. Although the isotopic sources of the radiation have not been identified, NHK World suggests it’s due to residual contamination from the 2011 nuclear accident. A few other locations in Ibaraki Prefecture have previously measured as high as 2 µSv/hr. The seaside park is heavily visited in the summer and home to the “Japan Rocks” music festival, so the precautions were taken by MLIT because of widespread public radiation fears. It should be noted that 0.70 µSv/hr is the typical natural exposure for millions of Americans living healthy lives on the Colorado Plateau and ten times lower than the beaches of Brazil and Kerala, India. http://www.japancrush.com/2014/stories/beautiful-seaside-park-partially-closed-due-to-radiation-fears.html
Tritium has been found above Tepco’s ridiculously low limit in a groundwater well at F. Daiichi. The well is one of the twelve from which in-flowing groundwater from the inland mountains is being “pumped up” and stored before discharging it to the sea. The Tritium concentration found in a recent testing of the well was 1,700 Becquerels per liter. Tepco’s self-imposed limit is 1,500 Bq/l, some ten times lower that Japan’s national standard. Pumping from the well was terminated pending further testing. http://www.japantimes.co.jp/news/2014/05/28/national/tritium-in-fukushima-groundwater-tops-limit-for-discharge-into-sea/#.U4XQvqNOUdU
(Comment – Tritium is easily the most innocuous radioactive isotope involved with Fukushima groundwater. It is naturally-occurring, with many health spas and spring waters around the world exceeding the 1,500 Bq/l limit. For more objective information on this relatively harmless isotope, click “Background Information on Tritium” in the left-hand column.