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Regional News
| Article published Wednesday, April 24, 2002
68 nuclear plants found to have less
corrosion
By TOM HENRY
BLADE STAFF
WRITER
OAK HARBOR, Ohio - The extent of corrosion
uncovered at FirstEnergy Corp.’s Davis-Besse nuclear plant near here
clearly is not rampant throughout the nuclear industry, federal
officials said yesterday.
The U.S. Nuclear Regulatory
Commission, following a much-anticipated technical review, said that
none of the 68 other pressurized-water plants come close to having
as much reactor-head corrosion as Davis-Besse and that none of them
will be shut down for emergency repairs.
"We saw nothing that
justified immediate regulatory action on our part," Victor Dricks,
an NRC spokesman, said. "We don’t see anything that suggests the
same problem exists anywhere else."
The report brought a sigh
of relief from the nuclear industry, which had been left wondering
what might be found elsewhere after the NRC initiated a nationwide
review of other plants in response to the problems at
Davis-Besse.
"That’s obviously good news for the industry,"
Richard Wilkins, a FirstEnergy spokesman., said of the NRC’s
one-page report.
Sixty-nine of America’s 103 operating
nuclear plants have pressurized-water reactors, including
Davis-Besse.
In early March, after extensive corrosion was
found at Davis-Besse, the NRC gave the 68 other pressurized-water
plants 15 days to submit inspection records and detail any similar
corrosion problems they have had.
Several plants, including
one of the reactors at FirstEnergy’s Beaver Valley complex west of
Pittsburgh, reported having some rust - but nothing the NRC
considered out of the ordinary or a threat to public
safety.
A minor flange leak is normal. In most cases,
droplets of boric acid that might escape from the reactor are
vaporized upon contact with the hot reactor head, a 17-foot-wide
steel structure that heats up to about 550 degrees when reactors are
operating at approximately 600 degrees, NRC officials have
said.
The Davis-Besse corrosion is unusual because there was
so much leakage that 35 pounds of steel melted away from the 150-ton
reactor head, the NRC has said.
That presumably occurred over
the course of at least four years, as boric acid from the reactor
melted through the top six inches of metal and left only 3/8 of an
inch of stainless steel to hold back the hot reactor’s operating
pressure of 2,200 pounds per square inch, the NRC has
said.
The NRC has acknowledged in recent weeks that it was as
surprised as anyone about the strength of that thin layer of steel,
explaining that it was not designed to hold back that much pressure
on its own.
Had a hole popped in the reactor head, the public
would have lost one of its biggest lines of defense and would have
had to rely solely on the thick concrete walls of the containment
structure to hold back all radioactive steam that would have escaped
from the reactor, officials have said.
Davis-Besse has been
shut down since Feb. 16, when it was taken off line for normal
refueling and maintenance. The worst of its corrosion problems were
discovered March 7. Another deep rust spot was found days
later.
Last week, FirstEnergy filed its own assessment of how
the problem got so bad. The NRC is in the process of reviewing that
and has instructed the utility to provide more information in
advance of an upcoming meeting to discuss that report.
Steve
Kerekes, spokesman for the Nuclear Energy Institute in Washington,
agreed yesterday that the Davis-Besse situation has national
implications for the industry.
"The issue is, are we
monitoring and managing [nuclear plants] effectively?" Mr. Kerekes
said.
He said the NRC’s assessment of other plants suggests
Davis-Besse’s situation is atypical. He said he "can’t predict how
that’s going to play out" in terms of a precedent.
The NRC
also would not speculate. "It’s too soon to offer any insight into
what it will mean in the future. Our focus continues to be on
Davis-Besse and its repair plan once it’s submitted," Mr. Dricks
said.
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