How the world's nuclear research reactors are fuelled makes a difference. In fact, the type of fuel they use has become a serious concern on safety and security grounds. A focal point is fresh and spent highly enriched uranium (HEU) fuel that remains on site at many shut down research reactors, says the IAEA's Crosscutting Co-ordinator for Nuclear Research Reactors, Mr. Iain Ritchie.
Since 1993 the Agency has worked to help countries upgrade safety and security at research reactors, particularly at shutdown reactors that have no plans for decommissioning and decontamination. The problems are significant, funds limited, and the work ever growing.
Researchers have long used small nuclear reactors as engines of discovery for everything from lifesaving cancer treatment to electronic gadgetry. But the use and future of research reactors is radically changing in a more economically competitive, and safety-conscious world.
Historically, HEU was the fuel of choice to power research reactors. It is also a key safeguarded material that can be processed and used to make a nuclear weapon. Most research reactors are located in nuclear-weapon States, but some are in countries yet to conclude safeguards agreements with the Agency.
"To have to imagine that all this spent fuel, in all these little research reactors, is scattered all over the world is crazy," says Mr. Allan Krass, Physical Science Officer, US State Department. "We know of a number of countries where the economy is in intensive care, the political situation is completely unstable and yet they have a research reactor with a spent fuel pool," Mr. Krass said.
In the past, the US supplied the bulk of HEU fuel and reactors in North America and the Asia Pacific, while the former Soviet Union supplied enriched fuel and HEU reactors to Eastern Europe. There are various "take back" initiatives underway to return this spent fuel to the countries of origin for safe disposal.
"There is no country that enjoys taking back spent fuel - it's a political headache. Yet it is irresponsible to just imagine that you can leave that where it is indefinitely," Mr. Krass said.
In some cases stocks of highly radioactive spent fuel are stored in an unsafe manner, corroding away. In other instances, spent fuel had been building up for years, for longer periods, and in large quantities, than originally planned. About one-third of all spent research reactor fuel is HEU spent fuel. The IAEA's research reactor database reveals the extent of the spent fuel problem:
Of the 382 shut down research reactors worldwide, less than half are decommissioned. The IAEA's focus is on the 27 shut down research reactors in developing Member States.
"Of the 27 in question, those with safety concerns and serious spent fuel problems are well known to us and we are trying to improve maters," Mr. Ritchie said. Of particular priority, reactors that have been shut down for more than a year with no plans for decommissioning; and reactors or spent fuel storage pools housing leaking fuel assemblies or exotic fuels that require special management.
The Agency's work in this area includes: