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Regional News
| Article published Thursday, December 5, 2002
DAVIS-BESSE
Regulators clueless to leak extent
After year, NRC explains delay in shutdown
order
By TOM HENRY
BLADE STAFF
WRITER
OAK HARBOR - Senior Nuclear Regulatory
Commission officials suspected there might be minor leakage on the
reactor head at the Davis-Besse nuclear plant, but they rejected a
staff recommendation that the plant shut down immediately late last
year because they considered the public risk "acceptably small,"
according to a report released yesterday.
In hindsight, the
agency has repeatedly admitted, it was caught off guard by the
magnitude of the what was found during an inspection after the
reactor was shut down Feb. 16 for refueling: the most serious
corrosion ever seen on a reactor head in the United
States.
The extent of the damage was so severe that the NRC
and other nuclear experts have since concluded that deterioration at
Davis-Besse was the nation’s closest brush with a major nuclear
accident since Three Mile Island in 1979.
Davis-Besse’s
carbon steel reactor head had been eaten away in one-half-foot area
to the point that only a stainless steel liner less than a quarter
of an inch thick had prevented a disastrous leak of the reactor’s
radioactive steam into the concrete containment building - the last
line of defense protecting the public.
The discovery was made
almost three weeks after FirstEnergy Corp. shut down the plant for
refueling on Feb. 16, a date which utility officials had
successfully negotiated after being threatened last November with
what would have been the government’s first emergency shutdown order
of a nuclear plant since 1987.
Now, a year after the decision
to allow the utility to keep operating until early 2002 - and after
a great deal of prodding by anti-nuclear activists, some members of
Ohio’s congressional delegation and concerned residents - the NRC
has put in writing its technical justification for making that
compromise.
The report shows NRC officials suspected there
might be some type of minor leakage with one or two of the 69
reactor-head nozzles. Uranium–enriched fuel rods are lowered and
raised in the reactor to control the nuclear fission
process.
But the NRC report contends the agency did not have
a clue as to the extent of the corrosion from boric acid leaking out
of the nozzles and onto the reactor head.
"To their credit,
they based it [the report] on what they knew then," said David
Lochbaum, a nationally recognized nuclear-safety engineer for the
Union of Concerned Scientists..
But he added yesterday’s
report did little to convince him that the NRC lived up to its
mandate to ignore economic considerations and hold safety
tantamount.
Mr. Lochbaum is one of several activists long
convinced that FirstEnergy’s intensive lobbying efforts in
Washington last fall persuaded the NRC to back off an immediate shut
down as recommended by the staff.
Instead, the NRC let
Davis-Besse keep running until Feb. 16, a date they view as an
arbitrary halfway mark between the proposed Dec. 31 shutdown date
and the normal refueling outage cycle that the company had
originally planned for March 30.
"I think they just didn’t
have the spine to back up their order to shut down the plant," Mr.
Lochbaum said.
Paul Gunter, spokesman for the
Washington-based Nuclear Information and Resource Service,
agreed.
"These are the same excuses the agency offered
previously," said Mr. Gunter, who lobbied the NRC for months to put
its rationale in writing.
The NRC’s criminal investigation
unit, as well as its Office of Inspector General, are among those
still trying to determine what the NRC knew in advance of the
shutdown and whether FirstEnergy illegally withheld photographs of
the corrosion and other information so that the plant could remain
open. FirstEnergy has denied such assertions.
Richard
Wilkins, FirstEnergy spokesman, said the utility knew it had a leak
but that it was "under technical specifications" allowed by the
NRC.
"We assumed the risk to be minimal," he
said.
Another internal probe by a special NRC panel called
the "Lessons Learned Task Force" said in a report released in
October that the agency failed to live up to a commitment to
document its reasoning for the February shutdown date.
NRC
spokesman Jan Strasma had little to say when asked why the
explanation took a year to put in writing other than to state that
yesterday’s report was not in response to any single
occurrence.
"When we notified them [FirstEnergy] we were
extending the time period, we said we would be providing the NRC’s
rationale in separate correspondence. That was never done. So this
completes the commitment we had in that letter and also responds to
requests from various stakeholders," Mr. Strasma said.
NRC
staff members had wanted Davis-Besse shut no later than Dec. 31
because they feared Davis-Besse might have a problem much more
subtle and different than a thinned-out reactor head: tiny,
circumferential cracks in reactor-head nozzles.
Those type of
cracks had not been seen in the industry until the spring of 2001,
when they were found at a South Carolina plant manufactured by the
same company that designed Davis-Besse.
They are potentially
more troublesome than vertical cracks because of their potential to
weaken nozzles to the point they could pop off the reactor head like
champagne corks, allowing radioactive steam to fill up the
containment building, officials have said.
As it turned out,
Davis-Besse had several axial cracks and at least two of the more
dangerous circumferential type, according to laboratory results and
government records.
The plant was one of a dozen identified
by an industry group a year ago as being most susceptible to having
circumferential cracks in its reactor-head nozzles.
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