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- BUCHANAN, NY - Consolidated
Edison officials said tonight that the steam generator that leaked radioactivity
Tuesday night at the Indian Point 2 nuclear plant, setting off a wide alert,
had begun showing signs of a leakage problem several weeks ago.
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- But officials said the problem did not seem serious enough
to merit corrective action like shutting down the plant.
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- That early warning is one of several items likely to
be reviewed as officials sort through Tuesday's leak, which led to the
most serious incident since the plant opened in 1974. The alert at the
plant ended at 6:50 p.m. today, nearly 24 hours after the accident occurred.
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- If any radiation escaped into the air after radioactive
water and gas leaked inside the plant, the levels were so low as to pose
no possible health risks, officials said today.
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- But experts said that even if the accident posed no health
threat, it raised questions about the viability of the 26-year-old reactor.
Replacing the damaged generator would be enormously expensive, and any
indication that the plant has serious problems would make it difficult
for Con Ed to find a buyer.
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- The company recently said it was seeking bidders for
the plant.
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- Of particular interest to investigators is increased
leakage detected this month in the Number 24 generator, the one that failed
Tuesday night. This is one of four devices that, using heat from the nuclear
core, generate steam that drives turbines, producing electricity.
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- Normal leakage is about 2 gallons a day in a generator
system that circulates millions of gallons daily. About a week ago the
leakage rate rose by as much as a half-gallon a day. The additional leakage
all came from the generator that sprang the much larger leak Tuesday night.
By contrast, that sudden leak had a rate of more than 75 gallons a minute,
Con Ed officials said.
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- James Baumstark, vice president for nuclear engineering
at Con Ed, said federal inspectors from the Nuclear Regulatory Commission
permanently stationed at the plant never indicated before the incident
that the rise in leakage from the suspect generator was serious enough
to shut the plant down.
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- Instead, Con Ed's plant managers ordered plant operators
to be on heightened alert in case the early leaks were hinting at a larger
failure in the steam generator's innards, which are a nest of thin-walled
pipes.
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- "We were basically monitoring it on a day-to-day
basis," Mr. Baumstark said. "Crews were alert to the potential
of a steam generator leak such as occurred last night."
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- Officials said that luckily, when the incident occurred,
safety systems prevented any significant release of radiation. Using calculations
to determine the worst possible case, Stephen Quinn, a Con Ed vice president
who once managed the plant, said the greatest release of radioactivity
outside the plant buildings would have been "one-fifth to one-twentieth
of the exposure you currently get just from walking in a park, standing
on a rock."
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- The incident was apparently set off when one or more
of the 3,200 pipes inside the No. 24 generator leaked, allowing perhaps
5,000 gallons of radioactive water heated by the nuclear core to mix with
clean water used to generate steam and run turbines, Mr. Quinn said.
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- The steam generators have long been considered one of
the weakest links in the equipment that turns energy from splitting uranium
atoms into electricity. Inside the generators, contaminated water and clean
water are separated only by the thin walls of a nickel-based alloy, chosen
not for strength or corrosion resistance but for ability to transfer heat.
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- These tubes have long been known to crack and erode under
years of use as hot, high-pressure water wears away the metal, or sludges
from impurities in the water cause corrosion.
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- It will probably take a week of work before the domed
containment building will be sufficiently decontaminated for engineers
to begin determining the source of the accident, Con Ed officials said.
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- In a week or so, investigators plan to send small robotic
inspection devices into the leaky steam generator, Mr. Quinn said at a
news briefing.
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- Of the four levels of nuclear accident classification,
Tuesday's was the second from the bottom.
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- On Tuesday night, Con Ed officials said that radioactive
gas leaked into the air from a plant system that ejects air from the steam
process to avoid corrosion. But tonight, Mr. Quinn said, it remained unclear
if any radiation at all escaped and wafted into the night air before an
emergency valve shut and shunted any gas back into the sealed dome.
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- He said that 16 radiation detectors taking constant readings
around the perimeter of the plant and a mobile team from the Westchester
County Health Department, using hand-held detectors, never found any signs
of a rise in radiation outside the complex.
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- But if the accident was small, its impact could be large,
especially because the company recently began accepting bids to sell the
plant.
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- "It certainly tells a potential buyer to hesitate,
to see how big the problem is," said David Wooley, a professor of
environmental and energy law at the Pace University Law School, in White
Plains. And, he added, "if you've lost one tube, that's an indication
you've got an aging generator, and you're going to see it again."
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- Another professor at Pace, Edward Smeloff of the Pace
University Energy Project, said it was not clear what the incident would
mean to the life expectancy of Indian Point 2, but noted that "this
has been a seminal event in the history of other reactors." Mr. Smeloff,
a former utility executive, listed Maine Yankee, in Wiscasset, Me., and
Trojan, near Portland, Ore., where, he said, steam generator problems "convinced
management to close the plant."
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- A spokesman for Con Edison, Joseph P. Petta, who was
asked how the event on Tuesday would influence a sale or affect the plant's
future, said "that's a premature question right now."
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- "Our focus right now, he said, "is on the events
at the plant." He would not say if any bids had been received, or
when the company expected to know the extent of the damage.
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- But Mr. Smelloff suggested that as New York deregulates
-- the reason that Con Ed was seeking to sell the plant -- the company
probably could not win approval from the Public Service Commission to risk
customers' money on major new investments, especially if the proceeds of
a sale would benefit the shareholders. And the company might think twice
about putting more of its own money in the plant.
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- It is not clear who would bear the extra cost if Indian
Point 2 closed now; under a "settlement agreement" with the Public
Service Commission, ratepayers are supposed to cover some of Con Ed's losses
in a sale, but the agreement contemplates a salable, operable plant.
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- Consolidated Edison has understood for years that the
steam generators at unit 2, numbered 21 through 24, would not last as long
as the plant's operating license, which lasts through 2013. But as the
finances of nuclear power have grown shaky, with some reactors around the
country being shut down and others being sold for a relative pittance,
the economic feasibility of replacing the generators has also grown uncertain.
Con Edison bought new generators 12 years ago and has them stored on site,
but according to its annual report, installing them could cost $100 million,
plus replacement power costs for a three-month shutdown.
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- Similar to the way the owner of an old car responds to
a fender-bender, the company may decide that the plant was totaled, because
its remaining value is too small to justify the expense of replacing the
generators, experts said.
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- Steam generators were on buyers' minds even before the
accident.
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- "With a steam generator event, one of first things
that I consider is, am I going to be faced with some huge capital expenditure
soon after I acquire the plant?" said Shelby T. Brewer, the former
head of a company that designed nuclear plants, Combustion Engineering.
He is now shopping for reactors like Indian Point 2, which have been put
on the market because of deregulation. Mr. Brewer estimated that a reactor
the size of Indian Point could sell for $20 million to $30 million, but
that steam generator replacement could cost five times that much.
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- At a time when nuclear reactors are selling for pennies
on the dollar, relative to the capital invested in them, the buyers count
on making a profit by buying them dirt cheap, experts say. Any sign that
the plant will not run well, or will require long periods of shut-down,
is damning.
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