Continual weakening of standards threatens public safety
June 29, 2011
For the last 18 years environmental groups in Michigan have been warning that the Nuclear Regulatory Commission has weakened or ignored safety rules in order to allow the Palisades nuclear power plant to keep operating, and a new study seems to support that contention.
“Palisades is an accident waiting to happen because of deferred maintenance,” said Kevin Kamps of the watchdog group Beyond Nuclear.
In a major series on nuclear safety last week the Associated Press detailed a phenomenon that has long troubled watchers of the nuclear industry — wear and tear at the nation’s many old nuclear power plants has caused them to fall out of compliance with rules for leaking valves, cracking on steam generator tubes, metal corrosion and more, and rather than require repair federal regulators have relaxed the rules to accommodate the deteriorating plants.
In the case of Entergy’s 40-year-old Palisades plant which sits on the shore of Lake Michigan 45 miles west of Kalamazoo, the major problem is embrittlement of the reactor vessel, environmental groups say.
Palisades is a 798 Megawatt pressurized water reactor that has been operating since Dec. 1971. The plant is owned by Entergy which bought it from Consumers Energy in 2007.
Since the early 90s Michigan environmental groups have warned that neutron radiation from the nuclear chain reaction in the reactor core has reduced the ductility (capacity to deform under stress) of the metal in the reactor vessel.
In 2005 when the owners of Palisades applied for a 20 year extension of the operating license for the plant these groups warned that this embrittlement represents a catastrophic risk.
“If, during an emergency, cooling water is pumped into the thermally hot and highly pressurized reactor core, the “pressurized thermal shock” (PTS) could rupture the brittle reactor vessel like a hot glass under cold water, releasing catastrophic amounts of radioactivity into the air and waters of Lake Michigan, the source of drinking water (and so much more) to tens of millions of people downstream,” they said.
Between 2005 and 2007 most of Michigan’s environmental groups signed on to a legal challenge to the relicensing of Palisades, Kamps said, but the effort proved unsuccessful after a retired NRC employee who planned to serve as an expert witness on embitterment of the plant’s reactor withdrew from the process under threats of retaliation from his former employer.
“We got so steamrolled,” he said.
According to AP the NRC lowered the safety margin for acceptable radiation damage to reactor vessels for the second time last year.
The standard is based on a measurement known as a reactor vessel’s “reference temperature,” which predicts when it will become dangerously brittle and vulnerable to failure. Over the years, many plants have violated or come close to violating the standard.
As a result, the minimum standard was relaxed first by raising the reference temperature 50 percent, and then 78 percent above the original — even though a broken vessel could spill its radioactive contents into the environment.
Kamps said the he believes NRC has actually reduced the embrittlement standards around six times and he said that the reactor vessel status at Palisades has been specifically mentioned by the agency as a reason for changing the standards.
Palisades has been out of compliance for decades, according to Michael Keegan of Coalition for a Nuclear-Free Great Lakes in Monroe.
“Palisades first violated NRC’s pressurized thermal shock regulations in 1981, just ten years into operations,” he said back in May as the NRC prepared for its annual meeting on performance of the Palisades plant. “Rather than deal with its embrittlement or else shut down, Palisades has instead successfully pressured NRC to weaken the safety regulations time and again in order to allow it to keep operating, despite the risks.”
The onsite storage of the spent fuel at Palisades has also been identified as a problem.
In Sept. 2005 as part of the regimenting process at Palisades Ross Landsman, a retired NRC Nuclear Safety Engineer and Palisades Dry Cask Storage Inspector testified that the pads where Palisades stores casks of spent fuel rest on top of sand and would not be stable in the event of an earthquake.
Landsman said that his superiors opted to ignore repeated communications about violations in the seismic design of Palisades’ spent fuel storage area.
“They turned me down again because I was retiring and officially couldn’t bother them any more, but the point is, the pad is not safe to hold any loaded casks,” he said.
On Tuesday the legislature will hear testimony on safety issues at Michigan’s three nuclear power plants during a joint meeting of the House Energy and Technology and Military and Veterans Affairs and Homeland Security Committees.
Officials from DTE Energy, owners of the Fermi 2 nuclear power facility near Monroe; American Electric Power, of the Cook facility in Bridgman; and Entergy, of the Palisades plant, will make presentations.
“Whether threatened by natural disaster or human attack, the tragic events at Fukushima have stressed our need for caution and certainty when it comes to protecting our nuclear energy facilities,” said state Rep. Kurt Damrow (R-Port Austin), chair of the House Committee on Military and Veterans Affairs and Homeland Security. “To ensure the safety of our residents and communities, we must make protecting these facilities a top priority for Michigan.”
“… [T]his is the nuclear industry defending themselves against what’s been in the press lately on U.S. nuclear safety and Fukushima,” said energy activist Kay Cumbow.
Cumbow pointed out that in addition to damage to the reactor vessel at Palisades, DTE Energy’s Fermi 2 is a GE Mark 1 reactor of the type that melted down at Fukushima and some are calling for all such reactors to be shut down due to unresolved safety flaws.
“… [A]s many of the concerned public who are able, should attend this meeting to let these committee members know that Michigan citizens are very concerned about safety issues that present with these aging, problem-ridden reactors … and expect the Michigan legislators to take action to protect the public.”