CONTAMINATED lands, blighted by fallout from the Chernobyl nuclear disaster, could be cleaned up in a clever way: by growing biofuels. Belarus, the country affected by much of the fallout, is planning to use the crops to suck up the radioactive strontium and caesium and make the soil fit to grow food again within decades rather than hundreds of years.
A 40,000 square kilometre area of south-east Belarus is so stuffed with radioactive isotopes that rained down from the nearby Chernobyl nuclear power station in 1986 that it won’t be fit for growing food for hundreds of years, as the isotopes won’t have decayed sufficiently. But this week a team of Irish biofuels technologists is in the capital, Minsk, hoping to do a deal with state agencies to buy radioactive sugar beet and other crops grown on the contaminated land to make biofuels for sale across Europe.
The company, Greenfield Project Management, insists no radioactive material will get into the biofuel as only ethanol is distilled out. “In distillation, only the most volatile compounds rise up the tube. Everything else is left behind,” says Basil Miller of Greenfield. The heavy radioactive residues will be burned in a power station, producing a concentrated “radioactive ash”. This can be disposed of at existing treatment works for nuclear waste, he says.
The UN’s International Atomic Energy Agency is not so sure, however. Its head of waste, Didier Louvat, told New Scientist that, while the biofuels process should be safe, neither Belarus nor Ireland has an adequate way of disposing of the radioactive residues at present. “The disposal facilities Belarus set up after the Chernobyl accident are not acceptable, so they will need safe storage until they have something better.”
Belarus has been tight-lipped about the project, though it is clearly keen to tackle the problem. Last September Andrei Savinkh, Belarus representative at the UN in Geneva, called decontamination of the soil “the number one priority for the Belarus government”.
Chernobyl is in Ukraine, close to the Belarus border. But prevailing winds meant 80 per cent of the fallout from the burning reactor fell in Belarus. Both were then part of the Soviet Union. The accident left vegetation and soils heavily contaminated with strontium-90, caesium-137, plutonium and americium. The most heavily polluted areas remain evacuated but 8 million people live in a much wider contaminated zone.
Farmers grow some grain crops here. The radioactive material concentrates in roots and stalks, which they plough back into the soil after harvesting. So the soil is almost as contaminated now as it was after the accident. The Belarus government hopes that by growing biofuels and using the whole plant, it can cleanse the soil. “Instead of centuries of natural decay [of the radionuclides] this process will cut the time to 20 to 40 years,” Savinkh says.
Greenfield plans to build the first biofuels distillery next year at Mozyr, close to one of the most contaminated areas (see map). The €500 million plant will turn half a million cubic metres of crops a year into 700 million litres of biofuels, starting in 2011. As many as 10 more plants will follow provided funding can be raised, says Miller. The European Union reckons it will need about 25 billion litres of bioethanol by 2020 to meet green fuel targets.
One of Greenfield’s partners will be Belbiopharm, a state biotech company that wants to develop genetically modified crops able to clean the soil more quickly.
The hope is that in the long run these measures will make life safer for local people. A study in 1999 by Nick Beresford of the Centre for Ecology and Hydrology in Lancaster, UK, found that tens of thousands of people in the contaminated region are consuming dangerous levels of radioactivity in their food.
Author: F. Pearce