Well, I got half of what I wanted. They'll make me a rock star if they melt down a fuel assembly. It would have been a big job to off load all the fuel and start taking apart the core support struture ti get at that stuck impellar. Can you even inagine the dose of these compents?
It is just un-American that you say we got a large foreign object struck in the bottom of nuclear core and you refuse to get it.
It is just un-American that you say we got a large foreign object struck in the bottom of nuclear core and you refuse to get it.
You knew the startup was right around the corner...
Palisades Nuclear Power Plant returned to service after 55-day scheduled refueling outage
COVERT TOWNSHIP, MI — The Palisades Nuclear Power Plant was put back into service Sunday morning following a 55-day, 19-hour scheduled refueling and maintenance outage that began Jan. 19.
During the maintenance period, which was the plant's 23rd refueling outage, 64 used fuel assemblies were removed from the reactor vessel and replaced, according to a press release issued Sunday morning. Other major projects completed include inspections of the reactor vessel and the plant's two low pressure turbines.
Early in the inspection, 17 of the plant's 45 control rod drive housings, which protect the drives that allow rods to be inserted and withdrawn from the core reactor, were found to not meet inspection criteria. While there was no leaking associated with any of the housings, all 45 were replaced with new materials.
More than 1,000 outside workers assisted Palisades employees with outage work.
It was also announced during the outage on March 3 that Palisades' workers had found a broken piece of metal from an impeller blade that had lodged itself inside the plant's reactor.
Palisades workers were unable to remove the metal after it became stuck between a vessel wall and the flow skirt. Entergy Corp., which owns Palisades, said at the time it plans to leave the metal in the reactor since it's not a safety issue.
March 15 We are not out of the woods yet. I would still wory about poor workmanship and engineering. But I have no start up issues over the CRDMs.
(Insider Joke)
So there is Palisades first swipe.
Jan 30: "The power plant plans to replace the 17 housings and return to service once work is complete. "One intent of a refueling outage is to conduct inspections or work that cannot be completed when we're online," said Rose. "We will be replacing those 17 housings that did not meet our criteria, and as a proactive measure to ensure continued safety, we will replace several other housings that did meet our criteria. The housings will be replaced with housings of a different design and material.""
Here is the second swipe…I guess Palisades found some extra ability somewhere.
These remaining 8 CRDMs are hard to replace and they cost a tremendous dose of radiation to the employees.
Feb 6: "When asked why the plant wouldn’t replace all 45 control rod drives with the new design, Rose said the plant said the replacement of 38 was “all we have the ability to do with this outage.”
When asked why the plant wouldn’t replace all 45 control rod drives with the new design, Rose said the plant said the replacement of 38 was “all we have the ability to do with this outage.”"
Seems I was persuasive enough in the below…no doubt I influenced them. They are terrified with the fallout of those 8 not replaced leaking in the near future.
"Come on, in the 2012/2013 assumption in this outage is you would test 25% of the CRDM and find no cracks. Then test 25% thereafter. It is the normal condition that a plant finds no cracks on their CRDM throughout the life of the plant.
So far you found 17 CRDM having cracks …that is 37% of the rods. You usually find lots more cracks after the all the is results come in. If you can’t trust the agency to anticipate this blossoming level of degradation…how can we trust the agency to anticipate a leak? How come the agency didn’t see this coming? You know, there is a astonishing number of violations going back years with the CRDMs and quality. The 2012 leak violations was just a repeat of the 2001…and 2001 was violations repeat of other prior incidences.
Just saying, why wasn’t the state of the art with metallurgy able to predict in 2012 that Palisades would find “at least” 37% of their CRDMs had cracks in them. Believe me, based on all the past reports I read on this, you won’t disclose the full numbers of cracks in the CRDMs (more than one per CRDM) till after restart. Why can’t these licensee PhD metallurgist predict future flaws and cracks instead of justifying past flaws?
It is illegal to start-up and operate if they had evidence CRDM unidentified leakage was increasing…they assumed they didn’t have leaking CRDM because they didn’t have full vision of the CRDM. They didn't have perfect evidence that the unidentified leakage wasn't a CRDM leak.
Lets remember the incomplete information accident in the Davis Besse head event. The licensee and the NRC assumed the CDRM flanges were leaking when it was a crack through the CRDM nozzle and eating the head. Who in a new different accident is talking about they were “refusing to communicate uncertainty“.For decades there is a widespread mindset in these organization that piping cracks and flaws don’t lead to leaks. That is what is behind this.You get it, these CRDM leaks at Palisades tend to show up within a month or so of a start-up and the leak worsens quickly. I’ll bet you both leaks (2001 and 2012) actually started before start-up. Palisades has a pattern of calling a prohibited CRDM leaks not a leak….cold bodily waiting to the CRDM leak gets to .3 GPM unidentified leakage or more according to their procedures. They have a requirement not to operated with pressure boundary leak and they chose to ignore the rules!I am just saying next operating cycle, how can you trust these guys to follow the rules? How can you trust these guys with a pattern of behavior like this…when these guys have abnormal or increasing unidentified leaking, when they don’t have absolute proof a pressure boundary “is not leaking“…how can you trust them to do the right thing with incomplete information. Honestly, how can you trust these guys to meet the commitment they won’t operate with pressure boundary leakage again.
A different design and alloy has repeatedly failed in the past. The scientific way to handle this is put the “another new design” in a exact environmental mockup before attaching it on the vessel. Maybe even a hyper environment. Prove there will be no more cracks and flaws in the CRDMs for a decade through a simulated environment.How can we trust the agency to make sure a plant like Palisades is keying on accurate, up to date and real time information about pressure boundary leaks. When Palisades and the agency are knowingly keying off incomplete information…that they act “super” conservatively.Next operating cycle will they immediately shutdown the plant when a CRDM begins to leak like regulation requires. Will it take weeks and months to shutdown the plant over leaking CRDMs like in the two times in the past? In the leaks in 2001 and 2012 Palisades did that. That is a pattern.So Palisades destroyed their CRDMs through or a result of all the recent startups and shutdown?
Is the Pressurizer weld flaw today connected the all the CRDM cracks?
Does the NRC really think those pristine inspected rods without flaw in 2012 really didn’t have flaws…when two of them were discovered with cracks this outage?
And the industry says the incubation period for developing a crack is over ten years?
These vulnerable eight CRDMs not replaced this outage…is anyone thinking about the loss of NRC and industry credibility if any of them come up with cracks or leaks within the next operating period…maybe something worst."
PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE – PNO-III-14-002A
This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. Some of the information may not yet be fully verified or evaluated by the
Region III staff.
SUBJECT: UPDATE - PALISADES CONTROL ROD DRIVE MECHANISM HOUSING FLAWS
This Preliminary Notification updates information provided in PNO-III-14-002, associated with the licensee’s examination of the Control Rod Drive Mechanism (CRDM) housings, consistent with commitments made by the licensee to the Nuclear Regulatory Commission (NRC) following its previous outage. The CRDM housings are part of the reactor coolant system pressure boundary and are designed to prevent reactor coolant from leaking into the containment. The CRDMs aret the mechanisms that withdraw and insert the control rods into the reactor and extend from the reactor head to about 14 feet upward.
As a result of these examinations, the licensee identified flaws in 17 of the 45 CRDM housings and replaced all of the CRDM housings with new housings of a different design that is more resistant to developing this type of flaw. One of the 45 CRDM housings was replaced during the previous outage and the remaining 44 housings were replaced during the current refueling outage.
Two NRC resident inspectors, assigned full time on-site to inspect and assess licensee activities, and an NRC regional inspector and subject matter expert, who was pre-staged on-site at the start of the refueling outage, observed the licensee’s examination of the CRDM housings and continue to evaluate the licensee’s corrective actions for the identified flaws. Additionally, NRC headquarters and regional experts conducted an independent and detailed review of the licensee’s technical evaluations and destructive testing of four of the housings with identified flaws. Based upon its independent review and assessment, the NRC concluded that the CRDM housings’ structural integrity was not compromised while the plant was operating.
The NRC will document its conclusions in a publicly available inspection report.
The State of Michigan has been notified.
The information in this preliminary notification is current as of 11:00 a.m. (EDT) on
March 14, 2014.
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