Nuclear sandbags too hot to handle

Japanese engineers working at Fukushima face a new hazard — radioactive sandbags so deadly that standing next to them for a few minutes could be fatal.

The No 3 reactor building at the Fukushima Daiichi nuclear power plant in northeastern Japan. Picture: AFP

Japanese engineers trying to dismantle the melted reactors at the Fukushima Daiichi nuclear power plant face a new hazard — radioactive sandbags so deadly that standing next to them for a few minutes could be fatal.

The sandbags were intended to make life easier for the teams dealing with the aftermath of the nuclear disaster in 2011 when three reactors melted after a tsunami destroyed their cooling systems. Twenty-six tonnes of the bags were placed in basements beneath two of the reactors to ­absorb radioactivity from waste water.

They were stuffed with zeolite, minerals that can absorb caesium. Nine years after the disaster, the submerged sandbags have sucked up so much radiation that they now represent a deadly danger themselves.

Samples of zeolite removed from the bags contain caesium, producing huge amounts of radiation, while the sandbags are giving off up to four sieverts of radiation an hour. Fifteen minutes of exposure to this could cause haemorrhaging. After an hour, half of those exposed would eventually die as a result. The maximum lifetime recommended dose of radiation for humans is less than half a sievert.

Tokyo Electric Power Co (Tepco), which operates the plant, had intended to remove the contaminated water by the end of 2020. The complication caused by the sand means it will take three years longer, the latest delay to the decommissioning.

Tepco managers have admitted that the technology needed to finish the job does not exist and they do not have a full idea of how it will be achieved. Their stated goal of decommissioning by 2051 may be impossible, they said.

One of the biggest problems is the 170 tonnes of irradiated water coming out of the plant every day, much of it natural ground water that flows through the earth ­towards the sea, picking up radiation on the way. Tepco pumps it out and stores it in huge storage tanks, filtered of some, but not all, of its contaminants — 1.17 million tonnes so far. In two years, the storage space will run out.

The government wants to pour the water away, insisting that the diluting effect of the ­Pacific will render the radiation harmless, but it is opposed by North and South Korea and the local fishing industry, whose reputation has been ruined by the disaster.

The Times