New estimates of airborne cesium from the damaged Fukushima Daiichi nuclear plant and accusations that Tokyo Electric Power Co. executives considered pulling out their workers entirely in the early days of the crisis highlighted the news from Japan this week.
Recent developments related to the TEPCO reactors blacked out by a tsunami and earthquake nearly a year ago include:
Study Ups Cesium Release Estimate
Computer modeling made public Tuesday based on seawater samples taken by Japanese scientists estimated radiation releases from the accident were worse than originally thought. An analysis of water collected from 79 locations in the North Pacific last April and May concluded that between 30,000 and 40,000 terabecquerels of cesium-134 and cesium-137 were released into the atmosphere, the Mainichi Daily News reported. By comparison, an estimated 137,000 terabecquerels of cesium is estimated to have been released in the Chernobyl accident. The Meteorological Research Institute of the Japan Meteorological Agency and the Central Research Institute of the Electric Power Industry conducted the recent research.
Report: TEPCO Considered Abandoning Plant
This week saw publication of a report commissioned by a non-governmental group that included interviews with numerous high-ranking officials in Japan, including the former prime minister, as well as officials from the U.S. Nuclear Regulatory Commission. Among the new information in the 420-page report by the Investigation Commission on the Fukushima Daiichi Nuclear Accident are allegations that TEPCO President Masataka Shimizu repeatedly tried to reach Industry Minister Banri Kaieda and other high-ranking government officials on March 14 and 15. At that point in time, the Asahi Shimbun quoted the report’s head author and former Asahi editor as saying, numerous politicians and bureaucrats interviewed believed TEPCO intended to pull all of its workers from the plant. Around the same time, the report also said then-Prime Minister Naoto Kan expressed concern during a visit to TEPCO headquarters that Japan might be “occupied” by the U.S. and Russia if it could not control the accident. The report also documents high tensions between Japan and the U.S., whose officials were frustrated that Japan didn’t use its Self Defense Force more.
Robot Measures Radiation in Unit 2
Monday, a Quince 2 robot surveyed the fifth floor of unit 2. The robot took several radiation measurements across the floor, which is flush with the surface of the spent fuel tank and the top of the reactor. The air temperature was recorded at 11.1 C with 69.9 percent humidity. Atmospheric radiation doses varied from 44 millisieverts per hour to 220 mSv/h.