Thursday, March 29, 2012

Fukushima No.2 Reactor Has '10 Times The Fatal Dose' of Radiation


Meanhile The Original Contamination Data Was Dleted

TOKYO (AP) — One of Japan's crippled nuclear reactors still has fatally high radiation levels and hardly any water to cool it, according to an internal examination Tuesday that renews doubts about the plant's stability. A tool equipped with a tiny video camera, a thermometer, a dosimeter and a water gauge was used to assess damage inside the No. 2 reactor's containment chamber for the second time since the tsunami swept into the Fukushima Dai-ichi plant a year ago. The probe done in January failed to find the water surface and provided only images showing steam, unidentified parts and rusty metal surfaces scarred by exposure to radiation, heat and humidity. The data collected from the probes showed the damage from the disaster was so severe, the plant operator will have to develop special equipment and technology to tolerate the harsh environment and decommission the plant, a process expected to last decades. Tuesday's examination with an industrial endoscope detected radiation levels up to 10 times the fatal dose inside the chamber. Plant officials previously said more than half of melted fuel has breached the core and dropped to the floor of the primary containment vessel, some of it splashing against the wall or the floor. Particles from melted fuel have probably sent radiation levels up to dangerously high 70 sieverts per hour inside the container, said Junichi Matsumoto, spokesman for Tokyo Electric Power Co. "It's extremely high," he said, adding that an endoscope would last only 14 hours in that condition. "We have to develop equipment that can tolerate high radiation" when locating and removing melted fuel during the decommissioning. The probe also found the containment vessel — a beaker-shaped container enclosing the core — had cooling water up to only 60 centimeters (2 feet) from the bottom, far below the 10 meters (yards) estimated when the government declared the plant stable in December.

Fukushima Pref. deleted 5 days of radiation dispersion data just after meltdowns
The Fukushima Prefectural Government revealed on March 21 that it deleted five days of early radiation dispersion data almost entirely unread in the wake of the meltdowns at the Fukushima No. 1 nuclear plant. The data from the System for Prediction of Environmental Emergency Dose Information (SPEEDI) -- intended to predict the spread of radioactive contamination, information vital for issuing evacuation advisories -- was emailed to the prefectural government by the Ministry of Education, Culture, Sports, Science and Technology.>

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