IAEA: Radioactive materials found in seawater near Japan nuke plant

Radioactive materials have been detected in seawater near a quake-crippled nuclear power plant in Japan, the International Atomic Energy Agency said Wednesday. The IAEA cited reports from Japanese authorities that the Tokyo Electric Power Company detected the radioactive materials in seawater near a discharge canal. "Samples taken included levels of iodine-131, cesium-134, and cesium-137," it said in an update Wednesday (Manila time). It said the samples were found at one location near the Southern discharge canal at the Fukushima Daiichi nuclear power plant. "Japan's Nuclear and Industrial Safety Agency (NISA) has announced that contamination has been found in sea water samples taken close to the outlet of the Fukushima Daiichi plant. We have been informed by NISA about plans to monitor the marine environment," IAEA Special Adviser to the IAEA Director General on Scientific and Technical Affairs Graham Andrew said. To study a larger area of the marine environment, the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) plans to measure radioactivity around the plant from March 22 to 23. "Seawater will be collected from eight locations, and the Japan Atomic Energy Agency plans to analyze the samples and release results on 24 March. The analysis will include radionuclide concentrations found in sea water and dose rate in the air. The IAEA will continue to follow this information," the IAEA said. Andrew said there continues to be some improvements at the Fukushima Daiichi nuclear power plant, but the overall situation remains very serious. High levels of contamination have been measured in the locality of the plant, he said. "On the Fukushima site the highest concern remains the spent fuel in the storage ponds of each reactor unit, particularly Unit 4. Reactor Units1-3 remain of concern, in particular Unit 2," he said. "We have not received validated information for some time related to the containment integrity of Unit 1 so we are concerned that we do not know its exact status," he added. Gray smoke was observed from Unit 3 which led to the evacuation of plant personnel for several hours yesterday due to elevated dose rates, he said. In addition, white smoke or vapor was observed from Unit 2. Efforts continue in Unit 2 to connect AC to pumps etc. Work for the recovery of off-site power supply to Units 3 and 4 is also proceeding. Seawater is being injected into the reactor vessels of Units 1, 2 and 3. Water is being sprayed periodically into the spent fuel pools at Units 2, 3 and 4 but no information is available for the spent fuel pool of Unit 1. The IAEA said it still lacks data on water levels and temperatures in the spent fuel pools at Units 1, 3 and 4. However, there have been some positive developments concerning Units 5 and 6 that are in cold shutdown. Off-site power is now being used in Unit 5; the pressure of the reactor pressure vessel of both units has decreased; and water is being injected in to the reactor pressure vessel, as needed. IAEA monitoring of gamma dose rates and beta-gamma contamination has continued over the last 24 hours, Andrew said. This has been carried out together with the Japanese authorities to facilitate the comparison of results, he added. The IAEA said it took measurements at additional locations between 35 to 68 km from the Fukushima plant. Dose-rate results ranged from 0.8 to 9.1 microsieverts per hour. See infographic below. (Note: 1 millisievert = 1,000 microsieverts)
Click here for larger version Beta-gamma contamination measurements ranged from 0.08 to 0.9 MBq per square meter. More precise interpretation of the results will be possible based on measurements to be made of the composition of the radioactive material that has been released. The IAEA said it will have two monitoring teams in Japan in the coming days. One team will be in the Fukushima area and a separate team will undertake monitoring in Tokyo and the surrounding area. Meanwhile, the IAEA continues to receive data confirming high levels of radioactivity in food, notably spinach, in samples taken from 37 locations in the vicinity of five cities south of the Fukishima site. "This indicates that in four Prefectures some food products are above permissible levels. High levels of both Iodine-131 and Caesium-137 have been measured by the Japanese authorities in spinach and some other fresh vegetables, together with Iodine-131 in milk. However, as reported yesterday, distribution of food from the areas affected has been restricted. The Japanese authorities are monitoring the situation in the rest of the country," Andrew said. Further monitoring data will be provided by Japan to the IAEA/FAO on an ongoing basis, he added. — LBG, GMA News