Circular cracks aren't necessarily as insignificant as the NRC would have you believe...
From: "Russell D. Hoffman" <firstname.lastname@example.org>
Subject: Circular cracks aren't necessarily as insignificant as the NRC would have you believe...
To: Tom Henry, Toledo Blade
From: Russell Hoffman, Concerned Citizen
Re: Circular cracks aren't necessarily as insignificant as the NRC would have you believe...
Date: Dec. 6th, 2001
In your article in today's Toledo Blade (shown below), circular cracks are described as "troublesome because they have the potential to split and make it more difficult to move control rods inside the reactor," according to the NRC. The NRC has never been known to exaggerate a risk.
Actually, making it "more difficult to move control rods inside the reactor" is what one might call a "best case scenario problem" which these circular cracks might create. There are far far worse -- if presumably, somewhat less likely -- scenarios.
Circular cracks can lead to the nozzles in the reactor popping out like champagne corks. And won't THAT be a mess! You're talking an immediate LOCA (Loss Of Coolant Accident), with the potential for a full-scale core melt, with immediate deaths, and zero chance of entering the reactor dome for about 10,000 years -- and NO containment dome can withstand that kind of sustained radioactivity, heat, and pressure from within. Chernobyl's massive sarcophagus, built after its accident, is cracking. Ours would too.
Sure, at 598 degrees, cracks might propagate a little slower than at 605 degrees, but it's the pressure, not the heat, that will matter if a circular crack finds its starting point when it wraps around a reactor nozzle. The NRC is describing one possible result, and as usual they are ignoring numerous other possible results as "not credible", either because the event's likelihood is too rare (in the NRC's myopic viewpoint), or the event is so severe they don't dare think about it at all.
But for people living near the plant, how rare is rare enough? You have to ask that, because the severity of a "worst case scenario" resulting from this particular problem would be worse than any manmade disaster that has ever happened anywhere!
Even at Chernobyl, things never progressed as wildly as they could have, and yet even so, the latest figures I've been reading indicate that more than 32,000 people have died already as a result of that accident (many of them children), and undoubtedly many times that many will die in the coming decades, centuries, and millennia, and many more have been born deformed, or were stillborn, and will be born deformed or will be stillborn, because of Chernobyl. (Perhaps it is not quite 32,000 dead yet. Perhaps it is more. But the Nuclear Energy Institute, the propaganda arm of the nuclear industry, still claims that only about 30 people died as a result of Chernobyl, because they discount every cancer death that has occurred since the accident, and only count those who died during the initial event, or immediately thereafter from high exposure levels. Low-level radiation deaths are ignored. It is utterly inaccurate and irresponsible of NEI, yet also, utterly typical.)
Will Davis-Besse be our (first) Chernobyl?
Circular cracks are extremely dangerous things, and the NRC has no idea what they are dealing with. They don't know how fast these cracks can propagate, they don't know why they start, they don't know where the next one will be, or how dangerous it will be. Neither does anyone else. Please note the BBC article included below, which also came out today and shows that the nuclear powers-that-be are no wiser in Japan. Indeed, they have had a multitude of accidents, and they are undoubtedly going to have a really bad accident some day, just as we are.
It's just a matter of time, because every logical, humanitarian, scientific, economic -- or in any other way rational (or emotional) -- attempt to stop these plants from operating has been thwarted by the lap-dog NRC, the bull-headed DOE, and an utterly-insane nuclear industry. While America sleeps, these cracks just grow and grow, along with 1000 other problems. Sooner or later -- maybe tomorrow -- something's going to blow, unless we shut the plants down and bury the waste deep underground. (Please note that I am not advocating Yucca Mountain as a solution to our country's nuclear waste problems. There are numerous scientific problems with Yucca Mountain, but the first step is to stop producing the waste in the first place.)
P. O. Box 1936
Carlsbad, CA 92018
P.S. Please read my essay on circular cracks, written regarding the Oconee reactor and my local reactor, San Onofre, which also is susceptible to such cracking. It is one of several related items at this URL:
Here is a list I've put together of all nuclear power plants in America:
Here is a list of about 200 nuclear-related books and videos in my personal collection:
Here's your article, followed by a BBC news item. At the bottom is my full contact information.
U.S. spares Davis-Besse from safety shutdown
By TOM HENRY
BLADE STAFF WRITER
OAK HARBOR - The federal government has backed off its threat to shut down FirstEnergy Corp.ís Davis-Besse nuclear power plant, despite concerns that a vital reactor safety feature could be cracked.
The Nuclear Regulatory Commission announced yesterday that it will allow FirstEnergy to keep the plant running until Feb. 16, the utilityís new date to take the plant off-line temporarily for normal refueling. At that point, FirstEnergy could inspect the reactor head to see whether a problem exists.
Until then, control room operators will be instructed to make adjustments so the reactor head - a huge, dome-like structure that covers the top of the reactor - does not exceed 598 degrees. Thatís only seven degrees lower than the reactor headís normal running temperature of 605 degrees, but regulators believe it will be enough to keep any cracks that might exist from spreading, according to Victor Dricks, spokesman for the regulatory commissionís national headquarters.
"If there were any cracks, it would reduce the crack growth rate," he said.
The possibility of a rare government order to shut down the plant arose because the commission was not convinced that FirstEnergy had done enough to inspect 69 devices on reactor heads known as control rod drive mechanism nozzles. Those nozzles serve a primary safety function, because they are passageways for other pieces of equipment that help operators maintain control over the reactor.
FirstEnergy inspected the nozzles on top of Davis-Besseís reactor head when the plant was being refueled in 1996, 1998, and 2000. But the Nuclear Regulatory Commission was concerned that the inspections there and at other nuclear plants with pressurized water reactors were not thorough enough because of the surprise discovery of cracks in two nozzles at the Oconee Unit 3 plant in South Carolina.
That plantís design is nearly identical to Davis-Besseís. On Feb. 18, Duke Energy Corp. discovered unusual circumference-type cracks in two nozzles on top of its Oconee 3 reactor. That type of cracks is troublesome because they have the potential to split and make it more difficult to move control rods inside the reactor, the commission said.
A government contractor, the Electric Power Research Institute of Palo Alto, Calif., identified 13 plants with pressurized water reactors as being most susceptible to those cracks. Davis-Besse was one of the plants identified.
Davis-Besse had been the only plant left in that group that the government had not decided how to handle. FirstEnergy made a presentation to the commission in the Washington area last month, but the commission staff kept open the possibility of ordering a shutdown until yesterday. The government has not ordered an immediate, safety-related shutdown of a nuclear plant since 1987.
"Our contention is we had no indication of a problem here. If there was, we would have been taking action," FirstEnergy spokesman Richard Wilkins said.
Detroit Edison Co.ís Fermi II nuclear plant is not susceptible to this type of problem because it does not have the same type of reactor. It has a boiling-water reactor.
The following article was seen in Radiation Bulletin, December 6th, 2001:
Japan: Nuclear plant pipe ruptured under pressure
BBC Monitoring Service - United Kingdom; Dec 6, 2001
Text of report in English by Japanese news agency Kyodo
Tokyo, 6 December:
A steam pipe at Chubu Electric Power Co.'s Hamaoka nuclear plant
in Shizuoka Prefecture ruptured instantly under enormous pressure
last month, causing a radioactive steam leak, the plant's
operator and the government's nuclear body said Thursday.
The utility and the Nuclear Safety and Industrial Agency, which
have been looking into the cause of the 7 November accident, said
a "ductile fraction" caused the rupture as characteristic dimples
were detected in a cross-section of the pipe.
A ductile fraction has never occurred before in Japanese nuclear
plants, according to the company. Masatoshi Sakaguchi, deputy
head of the Hamaoka plant, said the phenomenon was "never
Chubu officials said they suspect the pressure was due to
explosive hydrogen combustion inside the pipe and they are
investigating to prove their hypothesis.
The pipe may also have ruptured as a result of shock caused by
the flow of water within it, the officials said.
The utility released the results of its analysis of the
cross-section of the carbon steel pipe, which has a diameter of
15 centimetres and is 1.1 cm thick.
The officials said a microscopic examination was conducted on 17
pipe fragments at a facility affiliated with Toshiba Corp and the
Japan Atomic Energy Research Institute.
It did not show signs of metal fatigue or corrosion, they added.
Hydrogen could have been generated in the pipe as radiation split
water molecules in the reactor, the agency said. Agency officials
also said it is difficult to pinpoint the cause of the rupture
due to the lack of direct evidence.
Steam containing a small amount of radioactive material leaked
from a pressure injection system at the plant's 540,000-kW No 1
reactor on 7 November.
Three days later, about 60 millilitres of radioactive water per
hour was found to be leaking inside the reactor. Source: Kyodo
News Service, Tokyo, in English 0609 gmt 6 Dec
/BBC Monitoring/ © BBC. World Reporter
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First posted December, 2001.
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