NEW YORK -- Supporting previous warnings from Western experts about the dangers of Soviet-built nuclear power plants, a federal intelligence report says that 10 reactors in Slovakia, Lithuania, Russia, Bulgaria and Ukraine face an abnormally high risk of failure.
The danger is attributed to design flaws, tattered economies, political disorder and weak regulatory oversight. The 10 reactors, at five locations, are the most dangerous among a group that poses "significant safety risks," the report says. It was prepared by the Energy Department, distributed to federal intelligence agencies and made available by the Natural Resources Defense Council, a private group trying to obtain financial aid for the plants.
"As a class," the report says, "these reactors continue to experience serious incidents, raising the specter of another accident akin to Chernobyl."
In 1986 the Soviet nuclear power station at Chernobyl near Kiev exploded in the world's worst nuclear accident, killing at least 31 people and spreading significant amounts of radiation across Europe.
All told, about 60 Soviet-designed reactors are operating in former Soviet republics and Eastern Europe.
Russian scientists and managers defend their reactors, saying Western criticism is rooted in ignorance and neglects a series of improvements. U.S. Energy Department officials have also pointed to "significant progress" made at the power plants.
While Western experts have often voiced alarm over the safety of the Soviet-designed plants, the federal report is unusual in that it specifies the 10 reactors as particularly worrisome. Because of diplomatic sensitivities, international agencies have tended to shy away from rating the degree of danger of such reactors country by country.
The 10 reactors are Bohunice units 1 and 2 in Slovakia, Ignalina units 1 and 2 in Lithuania, Kola units 1 and 2 in Russia, Kozloduy units 1 and 2 in Bulgaria, and Chernobyl units 1 and 3 in Ukraine.
Unit 2 at Chernobyl was shut down in 1991 after a dangerous fire, and unit 4 was buried in concrete after the 1986 disaster. The report ranks the two remaining Chernobyl reactors as having the highest risk, while the eight other reactors are lumped together in terms of danger.
In interviews, Energy Department officials tried to distance themselves from the May 1995 report, saying it had been put together over the past two years, was to be periodically updated and in some cases had failed to note improvements.
"We are concerned about the safety status of these plants," said Terry R. Lash, the Energy Department's director of nuclear science. "But I think the host countries have made significant progress in the last two years in making upgrades. Things are on the upswing."
Mr. Lash runs a $121 million program of technical assistance for nuclear plants in the former Soviet bloc, including the ones listed by the report as most dangerous.
House Republicans are threatening to cut such aid, although whether they will succeed is uncertain.
Anatoly Shurygin, science attache at the Russian Embassy in Washington, said the designs of Russian reactors were comparable to American ones in terms of safety or in some instances superior.
"The real problem is economic problems and difficulties," Mr. Shurygin said. "We would be happier to spend much more money for increasing safety."
Gosatomnadzor, a Russian nuclear regulatory agency, recently told a Russian news agency that the safety of the reactors under its jurisdiction was deteriorating, based on an analysis of plant operations and incidents since 1994.
The Natural Resources Defense Council has called for the creation of a $10 billion fund by the West that would allow the 10 highlighted reactors to be shut down and replaced. Western countries and international lending agencies have committed $1.2 billion to improve safety.