Headlines out of Japan this week surrounding Fukushima Daiichi focused predominantly on a recent tank leak and efforts to deal with the huge volume of water accumulating at the plant.
Recent developments at the Tokyo Electric Power Co. reactors blacked out by the 2011 earthquake and tsunami include:
Government to Take Charge
TEPCO has faced massive challenges from flooded buildings, leaking reactor pressure vessels and contaminated groundwater since the outset of the crisis. It runs multiple decontamination systems and has erected hundreds of storage tanks, but a 300-metric-ton leak from an aboveground tank discovered last week has prompted the Japanese government to take over efforts to contain contaminated water at the plant.
Prime Minister Shinzo Abe said Wednesday the government will become more involved in countermeasures at Fukushima, leaving less responsibility to TEPCO. Kyodo news also reported that Abe's government and TEPCO plan to release a new plan in September exploring options to deal with the buildup of water. Researchers with the Atomic Energy Society of Japan recently suggested one solution: releasing treated water into the ocean. According to the Mainichi Daily News, a panel investigating Fukushima reported that water processed by multi-nuclide removal systems at the plant could be diluted and released with background levels of radiation, although it would still contain elevated amounts of tritium.
Leak Likely Started in July
A TEPCO representative told the Nuclear Regulation Authority on Tuesday that the tank at the center of the recent INES level-3 incident likely began leaking last month. The Asahi Shimbun reported that TEPCO came to that conclusion based on beta-ray doses of workers who spent time at a nearby radio relay station. The utility also announced in a Monday release that the leaking tank had been moved from another area after workers found ground subsidence cracking a concrete pad beneath it. It was unclear if the subsidence or move caused the leak, but TEPCO nonetheless began draining two other tanks that had been relocated from the same spot.
TEPCO also came under fire recently for its monitoring of seawater near the plant and its efforts to inspect tanks. The Mainichi reported Thursday that the NRA had suggested increased scrutiny of tanks some 10 times in the year leading up to the leak. TEPCO had sent nine workers to inspect 930 tanks twice daily.