Fukushima plant head: Too early to foretell decommissioning

The March 2011 earthquake and tsunami broken cooling techniques on the Fukushima Daiichi plant, inflicting three reactors to soften and launch massive quantities of radiation. The operator, Tokyo Electric Power Company Holdings Inc., has been capable of stabilize the plant to the purpose the place the corporate can higher plan a decommissioning technique, anticipated to be prolonged and exceedingly difficult.

“Going forward, we have to face unconceivably difficult work such as retrieving the melted debris” from contained in the reactors, mentioned Ono, who heads the plant and is president of Fukushima Daiichi Decontamination & Decommissioning Engineering Co.

Earlier this yr, a remote-controlled underwater car efficiently collected a tiny pattern from inside one of many three melted reactors — solely a spoonful of about 880 tons of extremely radioactive melted gas and different particles that should be safely eliminated and saved.

The standing of the particles within the major containment chambers of the Unit 1, 2 and three reactors stays largely unknown, Ono mentioned.

Removal of melted particles is about to begin in Unit 2 someday after September this yr following a virtually two-year delay. The elimination of spent gas within the Unit 1 reactor’s cooling pool is about to start in 2027 after a 10-year delay due to the necessity to dismantle components of the constructing broken by hydrogen explosions.

The plant needs to be prepared for staff to lastly think about eradicating the melted particles from the reactors in any case spent gas is taken out of the cooling swimming pools by 2031, Ono mentioned.

The authorities is sustaining its unique purpose of finishing the plant’s decommissioning by 2051. But some specialists say eradicating the entire melted gas particles by then is not possible and recommend a Chernobyl-style entombment of the plant, an choice that might assist scale back well being dangers whereas the plant’s radioactivity step by step decreases.

“I still consider this goal as a major guidepost,” Ono mentioned. “We can’t say what will happen in 30 years. We can’t say, but roughly imagining the next 30 years, I believe that it is necessary to carefully and precisely build up the current plan in order to safely, steadily and quickly proceed with the decommissioning.”

Before that, nonetheless, the largest concern is the disposal of huge quantities of handled however nonetheless radioactive water from the plant, he mentioned.

Water used to chill the three broken reactors has leaked into the basements of the reactor buildings and has been collected and saved in about 1,000 tanks that cowl a lot of the plant’s grounds.

The authorities and TEPCO say the tanks should be eliminated so services could be constructed for the plant’s decommissioning. The tanks are anticipated to achieve their capability of 1.37 million tons later this yr.

Most of the radioactivity could be faraway from the water throughout remedy, however tritium can’t be separated, and low ranges of another radionuclides additionally stay. The authorities and TEPCO say they’ll make sure the water’s radioactivity is way under authorized limits and can dilute it with massive quantities of seawater earlier than its deliberate discharge into the ocean.

Local fishing communities have fiercely objected to the plan, saying their already broken enterprise will undergo extra due to the unfavourable picture brought on by the water launch. Neighboring international locations, together with China and South Korea, and Pacific Island nations have additionally raised security issues.

TEPCO plans to complete building of the services wanted for the water discharge within the spring after which obtain security approval from nuclear regulators. A remaining inspection and report by an International Atomic Energy Agency mission are anticipated earlier than the discharge begins.

The operator nonetheless must work on an “easy to understand” clarification and scientific proof to assist individuals perceive the discharge, Ono mentioned.

“The decommissioning of Fukushima Daiichi itself is based on the understanding and trust of everyone in society,” he mentioned.