COVERT TOWNSHIP, MI -- The leak that shut down Palisades
Nuclear Power Plant May 5 is one of a series of incidents that have
bedeviled the nuclear reactor in recent years.
Nuclear
Regulatory Commissioner Kristine Svinicki will tour Palisades
Nuclear Power Plant on Monday, May 13, at the invitation of U.S. Rep. Fred
Upton, who will accompany her.
Palisades
officials will host an open house to answer questions from the
public about the plant Tuesday, May 14, from 5 to 7 p.m. at the Beach Haven
Event Center in South Haven.
Entergy
Corp. bought Palisades from Consumers Energy in 2007 for $380 million. The
one-reactor plant, which is located along Lake Michigan in Covert Township,
supplies about 20 percent of the utility's power. The facility came online in
1971 and its license runs until 2031.
Below
is a timeline of incidents at Palisades since 2007, based on NRC reports and
previous MLive/Kalamazoo Gazette articles.
2007 -- Palisades' head of
security resigned amid revelations he had fabricated some of his credentials.
2008 -- An
NRC safety assessment found Palisades
failed “to recognize and assess the impact of radiological hazards in the
workplace.” The NRC found that Palisades failed to determine how
much radiation employees were exposed to after radiation monitors worn by the
workers warned of an exposure.
August 2008 --
Five workers were trapped for 90 minutes inside a high-temperature area when a
hatch malfunctioned. The NRC launched a probe and found the plant did not take
proper precautions to prevent such occurrences.
2009 -- During an
inspection, the NRC found
that workers failed to notice a problem in the pool where spent fuel rods are
kept. The finding, labeled a “low to moderate safety”risk that did
not endanger the public, kept Palisades on the NRC's list of plants that
required additional regulatory oversight for a second year. The plant’s 2009
safety assessment also found problems with human performance
regarding“error-prevention techniques.”
May 2010 -- A Palisades manager left the control room
without following protocol and the event was not reported within 24 hours, the
NRC found.
January 2011 -- Palisades operated at 55 percent power for
eight days after a cooling-water pump lost power when an electrical bus failed.
The event did not represent a threat to health and safety, the NRC said.
May 2011 -- While NRC inspectors were conducting a
routine test of the plant’s auxiliary feed water system, a turbine-driven pump
was tripped. Investigators
found a component of the pump that was greased and should not have been.
The NRC classified the event as a "low to moderate" safety significance.
August 2011 -- The NRC launched a special inspection after
the failure of a coupling that holds pipes together. It found
Palisades did not follow industry standards when choosing the coupling and the
cracking was preventable. Palisades replaced all couplings.
September 2011 -- Palisades shut down between Sept. 16 and
Sept. 20 for repairs, after workers
discovered a leaking valve in the system that cools the reactor.
September 2011 Palisades shut down for a week after a breaker fault
in the plant's electrical system Sept. 25, when a worker performing
maintenance on an electrical panel when a piece of metal came into contact with
another metal piece and caused an arc. There were no injuries reported. The NRC
launched a special investigation, the second in
two months. The investigation found that during the incident,
which it named of "substantial significance to safety," Palisades did
not follow proper safety protocols before the shutdown.
November 2011 -- The NRC bumped Palisades down a level to
the Regulatory Response column as a result of the May 2011 incident.
January 2012 -- Palisades shut down for 3-1/2 days to repair a
wearing seal on a control rod mechanism.
February 2012 -- The NRC downgraded
Palisades to the third regulatory column, making it among the
four-worst performing reactors in the U.S. The downgrade came as a result of
the two special investigations launched in 2011.
June 2012 -- Palisades shut down for a month to repair a leak
in its safety injection refueling water tank. Numerous cracks were
found within the 300,000-gallon storage tank, according to reports. When the
plant returned to service, the tank was still leaking, but due to its size, it
did not pose a safety risk, the NRC found.
July 2012 -- An independent review of Palisades found
"examples of a lack of accountability at all levels." The
study, conducted by Conger & Elsea Inc. in January and February 2012,
looked at plant operations related to human performance, safety-conscious work
environment, problem identification and resolution.
August 2012 -- Palisades shut down for 18 days to
repair a leak in the control rod mechanism drive in the containment building.
The NRC sent a three-inspector team and launched a special inspection of the
pressure-boundary leak. During the 30 days before the location of the leak was
discovered, up to 10,000 gallons of radioactive water leaked from the
containment vessel. The water was contained and did not pose a safety risk to
the public, the NRC found.
September 2012 -- An NRC inspector found what it
characterized as a small leak in
a valve in the service water system. The water was not radioactive
and did not represent a health or safety risk, the NRC said.
September 2012 -- Entergy sued the federal
government over a lack of a waste disposal site. The New
Orleans-based company said it paid the government $6 million in fees a year to
take its waste. Since the Department of Energy has not done so, Entergy said it
has spent an estimated $100 million storing the waste.
November 2012 -- Palisades shuts down for three days to repair a
steam leak inside the plant's auxiliary building.
November 2012 -- The NRC upgraded Palisades after an 11-day
inspection in September found that Entergy had made
improvements and addressed deficiencies. The NRC ordered an
additional 1,000 hours of inspections in 2013, on top of the standard 2,000
hours.
February 2013 -- Palisades shut down for six days to repair a leak in
the component cooling water system. It was leaking 35 gallons of
non-radioactive water an hour before the shutdown, the NRC said. The leak did
not represent a threat to the public or the plant, the NRC said.
March 2013 -- Palisades was one of three
U.S. plants with significant safety events, or "near-misses" in the
past three years, according to a report by the independent Union of
Concerned Scientists. The near-misses at Palisades resulted from long-standing
problems, the UCS said, and it charged the NRC with failing to enforce
violations.
May 2013 -- On May 5, Palisades shut down after the
leak in the safety injection refueling water tank accelerated from one a day to
90 gallons within a 24-hour period, the NRC said. On May 4, before the
shutdown, some 79 gallons
of radioactive water from the tank went down a drain into a capture basin,
where it was extremely diluted, according to the NRC, and ended up in Lake
Michigan. The NRC has sent an additional inspector to Palisades, and one of its
health physicists is also investigating the incident. As of May 10, Palisades
was still offline while workers and inspectors search for the source of the
leak and make repairs.
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