Superstorm Sandy Shows Nuclear Plants Who’s Boss
Tuesday, 30 October 2012
11:30l
Once there was an ocean liner; its builders said it was unsinkable. Nature had
other ideas.
On Monday evening, as
Hurricane Sandy was becoming Post-Tropical Cyclone Sandy, pushing record
amounts of water on to Atlantic shores from the Carolinas to Connecticut ,
the Nuclear Regulatory Commission issued a statement. Oyster Creek, the
nation’s oldest operating nuclear reactor, was under an Alert. . .
and under a good deal of water.
As reported earlier,
Oyster Creek’s coolant intake structure was surrounded by floodwaters that
arrived with Sandy .
Oyster Creek’s 47-year-old design requires massive amounts of external water
that must be actively pumped through the plant to keep it cool. Even when the
reactor is offline, as was the case on Monday, water must circulate through the
spent fuel pools to keep them from overheating, risking fire and airborne
radioactive contamination.
With the reactor shut
down, the facility is dependant on external power to keep water circulating.
But even if the grid holds up, rising waters could
trigger a troubling scenario:
The water
level was more than six feet above normal. At seven feet, the plant would lose
the ability to cool its spent fuel pool in the normal fashion, according to
Neil Sheehan, a spokesman for the Nuclear Regulatory Commission.
The plant
would probably have to switch to using fire hoses to pump in extra water to
make up for evaporation, Mr. Sheehan said, because it could no longer pull
water out of Barnegat Bay and circulate it through a heat exchanger, to cool
the water in the pool.
If hoses desperately
pouring water on endangered spent fuel pools remind you of Fukushima ,
it should. Oyster Creek is the same model of GE boiling water reactor that
failed so catastrophically in Japan .
The NRC press release (PDF) made
a point–echoed in most traditional media reports–of noting that Oyster Creek’s
reactor was shut down. As nuclear engineerArnie Gundersen told
Democracy Now! before the Alert was declared:
[Oyster
Creek is] in a refueling outage. That means that all the nuclear fuel is not in
the nuclear reactor, but it’s over in the spent fuel pool. And in that
condition, there’s no backup power for the spent fuel pools. So, if Oyster
Creek were to lose its offsite power—and, frankly, that’s really likely—there
would be no way cool that nuclear fuel that’s in the fuel pool until they get
the power reestablished. Nuclear fuel pools don’t have to be cooled by diesels
per the old Nuclear Regulatory Commission regulations.
A site blackout (SBO)
or a loss of coolant issue at Oyster Creek puts all of the nuclear fuel and
high-level radioactive waste at risk. The plant being offline does not change that,
though it does, in this case, increase the risk of an SBO.
But in the statement
from the NRC, there was also another point they wanted to underscore (or one
could even say “brag on”): “As of 9 p.m. EDT Monday, no plants had to shut down
as a result of the storm.”
If only regulators had
held on to that release just one more
minute. . . .
The
shutdown was caused by an electrical grid disturbance that caused the unit’s
output breakers to open. When the unit’s electrical output breakers open, there
is nowhere to “push” or transmit the power and the unit is appropriately
designed to shut down under these conditions.
“Our
preliminary investigation identified a lighting pole in the Scriba switchyard
that had fallen onto an electrical component. This is believed to have caused
the grid disturbance. We continue to evaluate conditions in the switchyard,”
said Jill Lyon, company spokesperson.
Nine Mile Point
Nuclear Station consists of two GE boiling water reactors, one of which would
be the oldest operating in the US
were it not for Oyster Creek. They are located just outside Oswego ,
NY , on the shores of Lake
Ontario . Just one week
ago, Unit 1–the older reactor–declared an “unusual event” as the result of a
fire in an electrical panel. Then, on Monday, the reactor scrammed because of a
grid disturbance, likely caused by a lighting pole knocked over by Sandy ’s
high winds.
An hour and forty-five
minutes later, and 250 miles southeast, another of the nation’s ancient
reactors also scrammed because of an interruption in offsite power. Indian
Point, the very old and very contentious nuclear facility less than an hour’s
drive north of New York City , shut down because of
“external grid issues.” And Superstorm Sandy has given Metropolitan
New York’s grid a lot of issues.
While neither of these
shutdowns is considered catastrophic, they are not as trivial as the plant
operators and federal regulators would have you believe. First, emergency shutdowns–scrams–are
not stress-free events, even for the most robust of reactors. As discussed here
before, it is akin to slamming the breaks on a
speeding locomotive. These scrams cause wear and tear aging reactors
can ill afford.
Second, scrams produce
pressure that usually leads to the venting of some radioactive vapor. Operators
and the NRC will tell you that these releases are well within “permissible”
levels–what they can’t tell you is that “permissible” is the same as “safe.”
If these plants were
offline, or running at reduced power, the scrams would not have been as hard on
the reactors or the environment. Hitting the breaks at 25 mph is easier on a
car than slamming them while going 65. But the NRC does not have a
policy of ordering shutdowns or reductions in capacity in advance of a massive
storm. In fact, the NRC has no blanket protocol for these
situations, period. By Monday morning, regulators agreed to dispatch extra inspectors
to nuclear plants in harm’s way (and they gave them sat phones,
too!), but they left it to private nuclear utility operators to decide what
would be done in advance to prepare for the predicted natural disaster.
Operators and the
Nuclear Regulatory Commission spokes-folks like to remind all who will listen
(or, at least, all who will transcribe) that nuclear reactors are the
proverbial house of bricks–a hurricane might huff and puff, but the reinforced
concrete that makes up a typical containment building will not blow in. But
that’s not the issue, and the NRC, at least, should know it.
Loss of power (SBOs)
and loss of coolant accidents (LOCAs) are what nuclear watchdogs were warning
about in advance of Sandy , and they are exactly
the problems that presented themselves in New York
and New Jersey
when the storm hit.
The engineers of the
Titanic claimed that they had built the unsinkable ship, but human error,
corners cut on construction, and a big chunk of ice cast such hubris asunder.
Nuclear engineers, regulators and operators love to talk of four-inch thick
walls and “defense-in-depth” backup systems, but the planet is literally
littered with the fallout of their folly.
Nuclear power
systems are too complex and too dangerous for the best of times and the best
laid plans. How are they supposed to survive the worst of times and no plans at
all?
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