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Dr. Kudak, a nuclear-engineering professor at the Massachusetts Institute of Technology, is leading an effort to design a ''pebble-bed'' reactor - a nuclear reactor that he says could be built quickly, operated cheaply and have no chance of meltdown.
Some of the group's leaders said Dr. Kudak's concept might be a natural fit for such a park - especially because, according to proponents, pebble-bed reactors are adept at burning plutonium-based fuels.
A proposed $2.4 billion plant at SRS would make plutonium-based nuclear-reactor fuels using surplus plutonium from the nation's nuclear-weapons stockpile.
Unlike current reactor designs, which are fueled by long, thin rods filled with pellets of radioactive uranium, the pebble-bed concept would use graphite ''pebbles,'' about the size of billiard balls, filled with thousands of uranium particles.
The reactors would use 360,000 pebbles to heat helium, the pressure of which would spin the turbines needed to produce electricity. The gas also would act as a coolant, much as water acts in most current reactors. But where a loss of water in current reactors would likely lead to an accident, loss of helium in a pebble bed would not cause a meltdown, Dr. Kudak said. The graphite shells surrounding the uranium fuel would prevent that, the professor said.
But the graphite is what concerns Dr. Edwin Lyman, the scientific director of the Nuclear Control Institute in Washington. Graphite can burn, Dr. Lyman said, raising the possibility of a fire in a pebble-bed reactor under some accident scenarios. The Chernobyl nuclear disaster in Russia was fueled by flaming graphite, Dr. Lyman said.
''There are a lot of serious unresolved questions with the reactor,'' Dr. Lyman said, ''I think it's premature for the people who are promoting it to make a lot of the claims that they are making.''
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