The top safety expert of the International Atomic Energy Agency today accused the U.S. Nuclear Regulatory Commission of "complacency" in dealing with accidents at Babcock & Wilcox atomic power plans that clearly indicated a possibility of a partial core meltdown a year before the Three Mile Island crisis.
Morris Rosen, who headed the two-man IAEA team sent to evaluate the Three Mile Island accident said he found it "unbelievable" that the reactor operators did not recognize early the first day that they had a very serious accident.
"They oxidized un unbelievable amount of that core," Rosen said. "I still think it's incredible. The Thermocouples [which read water temperatures] were telling they they had a disaster. I don't understand it."
Rosen also sharply criticized the performance of Metropolitan Edison, the company licensed to operate the Three Mile Island plant, declaring: "You can almost say the utility was irresponsible."
But the IAEA safety expert was particularly severe on the NRC for failing to take action that might have prevented an accident of this magnitude from taking place.
In the previous year, he said, the NRC had received reports of smaller accidents at Babcock & Wilcox plants that showed a strong possibility of uncovering the core in just the way it occured at Three Miles Island.
"I read one report where if you read the accident sequence they decribe, you conclude, 'My God, there's a problem here," Rosen said. "The guy who wrote that report was rather clear. Yet somebody on a different level decided there was no problem."
Rosen, an American who was branch chief for the accident analysis section of the NRC before joining the IAEA in 1973, suggested that too many top people at the NRC had become "indoctrinated that there are no problems, so that if they saw one, they concluded it's not going to happen."
"It's time to say that maybe the people who are on the top at the NRC who have been a long time, ought to go," Rosen said. "These are extremely capable people but they've had the wrong judgment. It's as simple as that."
[A spokesman for the Nuclear Regulatory Commission said the NRC would have no comment on Rosen's remarks until it had time to study them.]
Rosen also said the available evidence indicated that there are "generic problems" with the Babcock & Wilcox reactors that make them less safe than other nuclear power plants. He expressed skepticism that these problems can be adequately dealt with during the current temporary shutdown approved by the NRC.
"It's a question of risk," said Rosen.He agreed that changes that will be made during the shutdown period, combined with new instructions to reactor operators, will probably prevent an exact repetition of the Three Mile Island accident.
Yet that approach, he said, failed to deal with what Rosen termed the apparent "improper desing" of the Babcock & Wilcox system.
"There's something different about the B&W system," he said. "It has to do with the once-through steam generator in particular. That steam generator, unfortunately perhaps, had a lot of economic benefits. But safety-wise, I don't think it responds to the same degree" as another reactors.
The big question, Rosen said, is whether there is another, thus far undiscovered, type of accident "connected with the improper design" of the Babcock & WILCOX REACTOR.
ROSEN POINTED TO A NUMBER OF DESIGN PROBLEMS, EQUIPMENT FAILURES AND HUMAN ERRORS THAT HAVE "SERIOUS IMPLICATIONS NOT JUST FOR BABCOCK & WILCOX PLANTS BUT ALL ATOMIC STATIONS.
"PERHAPS THE BIGGEST IMPLICATION TO ME IS THAT THE SAFETY SYSTEMS, AFTER THE FACT, ARE NOT BEING USED," ROSEN SAID. THE SYSTEM THAT WAS DESIGNED TO BRING A NUCLEAR REACTORY TO COLD SHUTDOWN, FOR EXAMPLE, IS NOT BEING EMPLOYED AT THREE MILE ISLAND BECAUSE IT WOULD PUMP CONTAMINATED WATER OUTSIDE THE CONTAINMENT AND INTO THE AUXILLARY BUILDING, INCREASING THE POTENTIAL FOR RADIATION LEAKAGE.
"IT'S A REASONABLE QUESTION TO ASK HOW COME PEOPLE OVERLOOKED SUCH A SIMPLE FACT," ROSEN SAID. HIS THEORY, HE CONTINUED, WAS THAT "DEEP DOWN NOBODY REALLY PICTURED IN HIS MIND THAT THERE WAS GOING TO BE A SITUATION WHERE YOU WOULD NOT WANT TO PUMP OUT OF THAT CONTAINMENT."
"NOW THAT'S A SERIOUS THOUGH," HE SAID.
ROSEN ALSO CITED AS A "FUNDAMENTAL DESIGN ERROR" THE FACT THAT SHORTLY AFTER THE START OF THE ACCIDENT, A SUMP PUMP AUTOMATICALLY BEGAN PUMPING CONTAMINATED WATER OUT OF THE CONTAINMENT INTO THE AUXILLARY BUILDING. THIS WATER ACCOUNTED FOR MUCH OF THE RADIATION LEAKAGE DURING THE THREE MILE ISLAND ACCIDENT.
ROSEN ALSO SHARPLY CRITCIZED METROPOLITAN EDISION, OPERATOR OF THE NUCLEAR PLANT, FOR ITS HANDLING OF THE ENTIRE AFFAIR.
"YOU CAN ALMOST SAY THE UTILITY WAS IRRESPONSIBLE," HE SAID.
DESPITE HIS CRITICISM OF THE NRC's failure to respond to earlier indications of problems with Babcock & Wilcox's plants, Rosen said he would rate the performance of the NRC during the Three Mile Island crisis as "reasonably good considering the circumstances."