#NUCLEAR REACTOR MELTDOWN TRIAL#

Ono says the goal is a good “guidepost” but too little is known. Once all the spent fuel is removed the focus will turn in 2031 to taking melted debris out of the reactors. Spent fuel removal from Unit 1 reactor’s cooling pool is to start in 2027 after a 10-year delay.

#NUCLEAR REACTOR MELTDOWN TRIAL#

Trial removal of melted debris will begin in Unit 2 later this year after a nearly two-year delay. That’s 10 times the amount of damaged fuel removed at the Three Mile Island cleanup following its 1979 partial core melt. Robotic probes have provided some information but the status of the melted debris is largely unknown.Īkira Ono, who heads the cleanup as president of TEPCO’s decommissioning unit, says the work is “unconceivably difficult.”Įarlier this year, a remote-controlled underwater vehicle successfully collected a tiny sample from inside Unit 1′s reactor - only a spoonful of about 880 tons of melted fuel debris in the three reactors. _ ANY PROGRESS WITH THE MELTED REACTORS? Massive amounts of fatally radioactive melted nuclear fuel remain inside the reactors. They have proposed long-term storage of the water by solidification, as used at the Savannah River waste repository in the U.S. “There should be a continuous, science-based effort to show other countries that it’s thoroughly handled, which I think is lacking the most.”Įnvironmental groups including Friends of the Earth oppose the release. If highly radioactive water escapes and is dispersed into the sea it becomes impossible to trace, a concern not only for Japan but also for countries in the Pacific, he said. University of Tokyo radiologist Katsumi Shozugawa said his analysis of groundwater in multiple locations in no-go zones near the plant has shown that tritium and other radioactive elements have been leaking into groundwater. Scientists say health impacts from consuming tritium and other radioisotopes through the food chain may be worse than from drinking it in water and further studies are needed.Ĭross-checks are another concern: TEPCO says water samples are shared with IAEA and the government-funded Japan Atomic Energy Agency, but experts would like to see independent cross-checks. The water release will be gradual and tritium concentrations will not exceed the plant’s pre-accident levels, TEPCO says. It will be also diluted, along with other radioactive isotopes, they say.

Tritium cannot be removed from the water but is unharmful in small amounts and is routinely released by any nuclear plant, officials say. TEPCO says the radioactivity can be reduced to safe levels and it will ensure that insufficiently filtered water is treated until it meets the legal limit. About 70% of the “ALPS-treated water,” named after the machines used to filter it, still contains Cesium and other radionuclides that exceed releasable limits. The 130 tons of contaminated water created daily is collected, treated and then stored in tanks, which now number about 1,000 and cover much of the plant’s grounds.

Water used to cool the reactors’ cores leaked into the basements of the reactor buildings and mixed with rainwater and groundwater. 1, 2 and 3 to melt and spew large amounts of radiation. A magnitude 9.0 quake on March 11, 2011, triggered a massive tsunami that destroyed the plant’s power supply and cooling systems, causing reactors No.

Nuclear reactor meltdown