Fast-bake fix straight from nuclear kitchen

Binding ties … Erden Sizgek and his wife, Devlet Sizgek, with a mock-up of the synroc plant.
Photo: Bob Pearce

The Sydney Morning Herald

By Richard Macey
April 26, 2006

ALMOST three decades after it was proclaimed the solution to the world's nuclear waste problem, construction of the first synroc plant is about to begin.
Unveiled in 1978 by Ted Ringwood, a geochemist from the Australian National University, synroc, or synthetic rock, was said to copy the way nature locked up radioactivity in the earth. But when Professor Ringwood died in 1993 there was little to show for his revolutionary idea.
"Synroc had a marketing problem," said George Collins, chief of research at the Australian Nuclear Science and Technology Organisation (ANSTO) at Lucas Heights. "It was designed for high-level waste, concentrated waste from the reprocessing of fuel from nuclear power stations. But not many countries have high-level waste."
But Dr Collins said synroc was "still a good idea". Instead of high-level nuclear waste, the synroc plant, to be operational in about two years, will store 5700 litres of intermediate-level waste produced at Lucas Heights during 30 years of making radioactive pharmaceuticals.
The waste, from an isotope called molybdenum-99, will be bound into artificial rock made from titanium oxide, using a process Dr Collins described as similar to baking a cake.
It re-created conditions near the planet's centre that naturally trapped radioactive elements such as uranium and thorium inside the crystal structures of rocks for millions of years.
The technique has been refined at ANSTO by a team led by a Turkish-born couple, Dr Erden Sizgek and his wife, Dr Devlet Sizgek, who have completed a scale mock-up of the synroc plant, often hammering out technical details over the dinner table.
The synroc and its waste would be put into cans and stored for ever at the proposed Northern Territory nuclear waste depot.