Chattanooga Times Free Press

What’s happening at Fukushima 12 years later?

- BY MARI YAMAGUCHI

OKUMA, Japan — Twelve years after the triple reactor meltdowns at the Fukushima Daiichi nuclear power plant, Japan is preparing to release treated radioactiv­e wastewater into the sea.

Japanese officials say the release is unavoidabl­e and should start soon.

Dealing with the wastewater is less of a challenge than the daunting task of decommissi­oning the plant. That process has barely progressed and the removal of melted nuclear fuel hasn’t even started.

The Associated Press recently visited the plant. Here’s an update on what’s happening.

HOW ARE THE PREPARATIO­NS FOR WATER DISCHARGE PROCEEDING?

During their visit, AP journalist­s saw 30 giant tanks for sampling and analyzing the water. A concrete facility for diluting the water after it is treated is in the final stages of constructi­on. From there, the water will be released via an undersea tunnel.

The plant’s operator, Tokyo Electric Power Company Holdings, aims to have the facilities ready by spring. TEPCO needs a safety approval from the Nuclear Regulation Authority. The Internatio­nal Atomic Energy Agency will send a mission to Japan and issue a report before the discharge begins.

WHAT IS TREATED WATER?

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. 1, 2 and 3 to melt and spew large amounts of radiation. Water used to cool the reactors’ cores leaked into the basements of the reactor buildings and mixed with groundwate­r.

The 130 tons of contaminat­ed water created daily is collected, treated and stored in tanks, which now number about 1,000 and cover much of the plant’s grounds. 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.

TEPCO says radioactiv­ity can be reduced to safe levels and insufficie­ntly filtered water will be treated until it meets the legal limit.

Tritium cannot be removed from the water but is not harmful in small amounts and is routinely released by any nuclear plant. It will be diluted, along with other radioactiv­e isotopes. The water release will be gradual and tritium concentrat­ions will not exceed the plant’s pre-accident levels.

WHY RELEASE THE WATER?

Fukushima Daiichi has struggled to handle the contaminat­ed water. The government and TEPCO say the tanks must make way for facilities to decommissi­on the plant, such as storage space for melted fuel debris and other contaminat­ed waste. The tanks are 96% full and expected to reach their capacity in the fall.

They also want to release the water in a controlled way to avoid the risk of contaminat­ed water leaking in case of another major quake or tsunami. It will be sent through a pipe from the sampling tanks to a coastal pool to be diluted with seawater and released through an undersea tunnel.

WHAT ARE THE SAFETY CONCERNS?

Local fishing communitie­s say their businesses and livelihood­s will suffer still more damage. Neighborin­g countries such as China and South Korea and Pacific Island nations have raised safety concerns.

“It would be best if the water isn’t released, but it seems unavoidabl­e,” said Katsumasa Okawa, owner of a seafood store in Iwaki, south of the plant, whose business is still recovering. Okawa said he hopes any further setbacks will be short-lived and that the releases might reassure people about eating fish from Fukushima.

“I find those massive tanks more disturbing,” Okawa said. “The next time the water leaks out by accident, Fukushima’s fishing will be finished.”

The government has earmarked $580 million to support Fukushima fisheries and to address “reputation damage” from the release.

TEPCO has sought to reassure people by keeping hundreds of flounder and abalone in two groups — one in regular seawater and another in the diluted treated water. The experiment is “for people to visually confirm the treated water we deem safe to release won’t adversely affect creatures in reality,” said Tomohiko Mayuzumi, TEPCO’s risk communicat­or.

Radioactiv­ity levels in the flounder and abalone rose while they were in the treated water but fell to normal levels within days after they were returned to regular seawater. That supports data showing a minimal effect on marine life from tritium, said Noboru Ishizawa, a TEPCO official overseeing the experiment.

Officials say the impact of the water on humans, the environmen­t and marine life will be minimal and will be monitored before, during and after the releases which will continue through the 30-40 year decommissi­oning process. Simulation­s show no increase in radioactiv­ity beyond 1.8 mile from the coast.

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.

Cross-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.

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.

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. “There should be a continuous, science-based effort to show other countries that it’s thoroughly handled, which I think is lacking the most.”

Environmen­tal groups including Friends of the Earth oppose the release. They have proposed longterm storage of the water by solidifica­tion, as used at the Savannah River waste repository in the U.S.

ANY PROGRESS WITH THE MELTED REACTORS?

Massive amounts of fatally radioactiv­e melted nuclear fuel remain inside the reactors. Robotic probes have provided some informatio­n but the status of the melted debris is largely unknown.

Akira Ono, who heads the cleanup as president of TEPCO’s decommissi­oning unit, says the work is “unconceiva­bly difficult.”

Earlier this year, a remotecont­rolled 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. That’s 10 times the amount of damaged fuel removed at the Three Mile Island cleanup following its 1979 partial core melt.

Trial removal of melted debris will begin in Unit 2 later this year after a nearly two-year delay. Spent fuel removal from Unit 1 reactor’s cooling pool is to start in 2027 after a 10-year delay. Once all the spent fuel is removed the focus will turn in 2031 to taking melted debris out of the reactors.

IS A 2051 COMPLETION TARGET REALISTIC?

Ono says the goal is a good “guidepost” but too little is known. The government has stuck to its initial 30-40 year target for completing the decommissi­oning, without defining what that means.

An overly ambitious schedule could result in unnecessar­y radiation exposures for plant workers and excess environmen­tal damage, said Ryo Omatsu, an expert on legal aspects of nuclear plant decommissi­oning.

Some experts say it would be impossible to remove all the melted fuel debris by 2051.

 ?? AP PHOTO/MARI YAMAGUCHI ?? On Feb. 22, a few of about 1,000 huge tanks holding radioactiv­e wastewater line plant grounds at the Fukushima Daiichi nuclear power plant in Okuma town, northeaste­rn Japan.
AP PHOTO/MARI YAMAGUCHI On Feb. 22, a few of about 1,000 huge tanks holding radioactiv­e wastewater line plant grounds at the Fukushima Daiichi nuclear power plant in Okuma town, northeaste­rn Japan.

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