May 28:
Democrat Paul Clements says Congressman Fred Upton is no longer a moderate Republican
Who he won't take money from
Clements did not rule out taking money from interests outside Michigan, but he said there are certain groups from whom he would not accept campaign contributions.
"I wouldn't take money from the Koch brothers, but I doubt they would want to give it to me," he said.
He also said he wouldn't take money from Entergy Corp., the owners of Palisades Nuclear Power Plant in Covert Township.
Palisades is "one of the most fragile, most accident-prone nuclear plants in the country," he said. "We need to be confident it is providing safe nuclear power or that it is moving toward a reasoned phase-out. We don't see that today – I think it represents a threat to us today and so I would not be comfortable accepting contributions from the company that owns it."
May 28:
May 26: Yep...the the extremist pro nukies ganged up on me and got me kicked off. I won't participate being moderated.
Note: It sure looks like Madalina has shifted me to a approving comment mode or worst. Or it could be issues with my computer or with Linkedin itself slowing down. But this has been going on for days so I find that unlikely.
"Your group posting status: LinkedinYour posts across groups are being moderated temporarily because one of your recent contributions was marked as spam or flagged for not being relevant. Learn more."
May 27
Senator Markey is watching Mike Mulligan...
Transcipts of 2.206May 21, 2014: Addendum to Palisades Broken Impeller 2.206
Today at 2:11 PM
Salem
“Sheehan said the bolts are about 4 inches long and about 1 inch wide.
Sheehan said one of the main concerns was having the bolt heads damage or stop the impeller at the bottom of the pump which spins and draws the water into the pump in then sends it into the reactor vessel. Also, Sheehan said, there could be the possibility of the impeller, moving at such a high rate of speed, striking and disintegrating a bolt head and sending tiny pieces of metal circulating throughout the cooling system and possibly causing damage.”
Think of the speeds and power he is talking about there: “impeller, moving at such a high rate of speed, striking and disintegrating a bolt head”. There is a lot more weight and metal in the Palisades blade that the bolts and nuts.Palisades
So the worst Palisades broken impeller blade is 5 inches wide by 12 inches long...by one inch thick.
Despite the application of approximately 3,000 pounds per square inch (psi) of force, the piece did not move. You know the velocity of the water caused that.
Though both IR 2012-03 and the current IR there has been no mention of an equivalent evaluation by Palisades as in Salem's PCP event. The operability of the PCP is a untouchable.
I request the NRC enforce a similar evaluation on the Palisades and I request a OIG inspection on why there is different analysis criteria for similar PCP events between the NRC regions.
Again, I request the Palisades plant be shut down until they replace their PCP with a safer design.
1) How many times did that large Palisades blade spin around in the pump casing before it was spit out? The size of the large broken blade found in Palisades challenges a sheared or frozen impeller accident that severely threatens fuel damage from reduced cooling as mention in Salem and IN 85-03.
2) Certainly the speed of the remaining impellers could shatter a broken blade or pieces and spew small metallic pieces throughout the coolant.
3) Palisades over the years should have carefully documented all the damage to the impellers and evaluated the size of the missing pieces. I am certain many small metallic pieces did get past the flow skirt impeller blade filter, indeed entered the fuel channel and circulated endlessly in the coolant. Why has there been no analysis on this?
4) There is a worry about all these blades pieces found at the bottom of the core upon inspection...there could have been eddies before entering the fuel channel and much erosion throughout the area in all the structures as the material was spinning around in in the under the core flow.
5) The metal blade particles in circulation could have cause erosion of the coolant piping walls throughout the system and also cause flaws in the coolant piping.
6) It certainly looks like larger and larger pieces of blades over time are breaking off the impeller. Has there been an internal evaluation on this?
7) Let’s face facts, in a 30 foot high 4000 hp motor and pump, with a large blade breaking off or more, it could shatter the impeller itself and also the pump casing.
If possible, I would like another chance to speak to the board.
Sincerely,
Mike MulliganHinsdale, NH
I initiated a NRC process called a 2.206 process on March 17, 2014 over Palisades.
Here is my 2.206 on it.
Back in ‘2011” I got on the docket, I predicted, we are going to be shocked with the magnitude of mind blowing Palisades problems in the next few years. I have unnerved many people over the years with my ability to predict future organizational events.
Remember recirculation damage is the explosive collapse of vapor bubbles…it blasts off microscopic metal particles of the impeller and the blades.May 15:
(It was shortly after the latest turbine trip w/i a day. I don’t know why I can’t come up with the right date. I have talked to numerous inspectors in the last month)
So around May 8 I called up the Salem NRC senior inspector and left a message. He shortly called me back. We talked about the problems with the recent plant trips. He reminded me he knew me from the Vermont Yankee issues. It was like we was old buddies. He was a NRC facilitator at a few of VY contentious community meetings. It was a few meetings past, just after the antis threw cow manure at the NRC inspectors.The NRC had a army of Brattleboro police officers in the meetings and surrounding the high school. There was talk about bringing in the tanks! I talked to this senior resident about the Palisades problems; spoke at length about the meaning of defective PCP impellers. Asked him can you believe the inspectors, said it was safe with the throwing impeller blades all over the place. He didn’t respond. We talked about their brackish service water piping problems...he reminded me they did a rather big piping replacement project.
I just wanted you to know we spent a lot of time talking about Palisades PCP pump problems and I am certain he memorialized the discussion to higher ups.
PSEG Nuclear has extended a refueling shutdown of its Salem Unit 2 reactor after discovery of unexplained broken bolt heads in part of the coolant system.Why aren't we showing a picture of the actually palisades damaged impeller. They say it only happens in startups and shutdowns. It just takes a very little amount of time to create this kind of damage.
Company spokesman Joe Delmar said Wednesday afternoon that "a conservative decision was made to extend the refueling outage to conduct additional internal inspections of the reactor coolant pumps and make any repairs as needed."
Nuclear Regulatory Commission spokesman Neil Sheehan said the bolt tops are likely from a part of the coolant pump system.
"The concern is that if bolts holding the turning vane failed, the vane could drop and impact the rotating pump internals," Sheehan said.
PSEG operates three reactors at its Artificial Island site along the Delaware River in New Jersey southeast of Port Penn. The company's Salem Unit 1 plant has reported three unplanned shutdowns this year, potentially subjecting the operation to increased oversight.
1) what if two huge chunks of blades come off right next to each other...a seriously unbalanced impeller. Big loca.
2) The blades winging down the piping system with dinging and gouging out piece of the pipe. They are sand blasting the the big primary coolant piping.
3) It is easy design change to fix the impeller in our modern world today.
Cavitation
4) The issue could end up being equal to a locked rotor accident, which has never happened. A locked rotor accident challenges the peak clad temperatures more than any one accident.
Note on the three below pictures, especially with the damaged pump on the floor:
The below picture represents the kind of cavitation damage you might see at the Palisades...these aren't actual Palisades pictures.
You notice it doesn't happened to one blade...it happens to all of the blades at same time.
The results of a damaged or misbalanced impeller.
Cavitation is a significant cause of wear in some engineering contexts. Collapsing voids that implode near to a metal surface cause cyclic stress through repeated implosion. This results in surface fatigue of the metal causing a type of wear also called "cavitation". The most common examples of this kind of wear are to pump impellers, and bends where a sudden change in the direction of liquid occurs. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial cavitation.
Inertial cavitation is the process where a void or bubble in a liquid rapidly collapses, producing a shock wave. Inertial cavitation occurs in nature in the strikes of mantis shrimps and pistol shrimps, as well as in the vascular tissues of plants. In man-made objects, it can occur in control valves, pumps, propellers and impellers.This report indicates a very seriously degraded and dangerous nuclear plant. A big event could pop of of the ether at any moment. They had a heavy lift near miss with the reactor head over "not following procedures" just like ANO.The NRC is also worried about the deteriorating service water system. The NRC documented three failures to follow procedures this period, the SG dam, the bladder getting sucked twice into the suction of the service water system and heavy lift on the reactor head.
05000255/2014002
1R20 Outage Activities (71111.20)
a. Inspection Scope
The inspectors evaluated outage
activities for a scheduled refueling outage that began on January 19, 2014, and
continued through March 18, 2014. The inspectors reviewed activities to ensure
that the licensee considered risk in developing, planning, and implementing the
outage schedule.
The inspectors observed or
reviewed the reactor shutdown and cooldown, outage equipment configuration and
risk management, electrical lineups, selected clearances, control and
monitoring of decay heat removal, control of containment activities, personnel
fatigue management, startup and heatup activities, and identification and resolution
of problems associated with the outage.
One of the planned refueling
outage activities of particular NRC interest was a foreign object search and
retrieval (FOSAR) activity in the reactor vessel. While licensee routinely
inspect for foreign material in plant systems and implement controls to prevent
the introduction of debris into plant systems, the licensee has in the past
identified broken pieces of primary coolant pump (PCP) impellers in the reactor
vessel. As a result of a PCP-C vibration transient on October 29, 2011, the
licensee suspected a piece of impeller might have broken off and entered the
reactor vessel.
Issues with PCP impellers at
Palisades date back to 1971 when the impeller for PCP-A was weld-repaired and
reinstalled due to damage from foreign material. Below is a timeline of continued
issues with PCP impellers.
1983: The licensee identified and
removed a piece of broken impeller from under the reactor core barrel during
core-offload as part of refueling outage activities. The licensee inspected all
of the PCPs and noted the piece originated from PCP-C. The damaged PCP-C
impeller was replaced with a new impeller in early 1984.
1984: The newly installed PCP-C
impeller failed due to improper assembly and required replacement. The licensee
acquired an impeller from another plant, trimmed theimpeller diameter to the
proper size, and installed the new impeller.
1999: The site commenced a
project to refurbish or replace the four PCPs. The
PCP-A impeller was removed for replacement with a spare unused impeller.
The removed impeller had
cracking on two of the five vanes that was attributed to inadequate post-weld heat treatment in
1971, and the impeller was weld-repaired for
future use.
2001: The weld-repaired impeller from PCP-A was installed
in PCP-B. This was the first impeller replacement for PCP-B and the removed
impeller had cracking in three of the five vanes. The removed impeller was
weld-repaired for future use.
2003: The licensee removed the trimmed impeller from
PCP-C for replacement and noted extensive damage such that repair was not
viable. The impeller was replaced with the refurbished impeller that had been
removed from PCP-B.
2007: The licensee identified and removed two impeller
pieces from the reactor vessel.
2009: The original impeller in PCP-D was removed and
replaced with a newly manufactured impeller. The original impeller was
subsequently inspected and found to have recirculation damage, but no cracking.
2014: The licensee removed the impeller from PCP-C and
replaced it with a newly manufactured impeller. The removed impeller had
missing portions in two impeller vanes.
The 2014 refueling outage
included the removal of the core barrel to support more comprehensive reactor
vessel inspections than can typically be conducted. This activity was pre-planned
for reasons not related to the pump impeller concern, but coincidentally allowed
for a more thorough inspection for foreign material in the reactor vessel. The licensee
anticipated finding the suspected broken piece from the PCP-C vibration event in
October 2011 in the vessel. The reactor vessel FOSAR activities identified two
pieces of broken impeller; one piece was removed from the vessel and the other
piece was lodged between the reactor vessel and the bottom corner of the flow
skirt. The licensee attempted to remove the lodged piece using several methodologies,
including pulling using vice grips and pushing using hydraulic tools. Despite
the application of approximately 3,000 pounds per square inch (psi) of force,
the piece did not move.
The reactor vessel is shown in
the figures below. Four PCPs circulate water through the PCS. After the water
has passed through the steam generators and transferred heat to the secondary
system, the water is pumped by the PCPs through the PCS cold legs and into the
reactor vessel. In the included figures that depict the Palisades PCS, one cold
leg (inlet nozzle) and one hot leg (outlet nozzle) are shown for the purpose of
simplicity. In actuality, there are four cold legs and two hot legs. Water
enters the reactor vessel via the cold legs and flows down between the reactor
vessel wall and the core support barrel. Near the bottom of the vessel is a
flow skirt that contains many small holes that most of the water flows through.
Some water also passes below the flow skirt into the bottom of the vessel.
After flowing through or under the flow skirt, the water then flows up into the
active fuel region to remove heat from the nuclear fuel. After flowing through the
fuel region, the water exits the vessel through the hot legs and into the steam
generators.
Since the licensee could not remove the impeller piece from the vessel, Operability Evaluation CR-PLP-2014-01510 was developed to evaluate the operability of the reactor vessel. The piece was tapered in thickness from 3/16 inches to roughly one inch wide, and the gap between the vessel wall and flow skirt where the piece was wedged was up to ½ inch wide. The piece was not blocking any of the flow holes through the flow skirt. Plant history has shown that prior broken impeller pieces that passed through the gap were found at the bottom of the vessel. The licensee performed a fluid dynamics analysis to determine the forces that would act on the piece during plant operation, which concluded that the maximum force would be a 350 pound lift force. The site then performed a structural analysis to determine the effects of the piece and hydraulic forces on the reactor vessel and flow skirt. Heatup and cooldown effects were considered and the flow skirt and vessel were determined to move together such that the gap size would remain constant. A fracture analysis was performed to determine if the piece would break up into smaller pieces during the operating cycle. The analysis assumed several initiating crack sizes in the piece, all of which determined that the crack growth rate would reduce and essentially stop once the crack depth approached 75 percent of the thickness of the piece. Based on the results of the analyses, the licensee concluded that the piece would not move, would not break up, would not impede PCS flow, and would not affect the pressure-retaining capability of the reactor vessel. The analyses were performed as a joint effort between the licensee and equipment vendors. The licensee’s Operability Evaluation concluded the reactor vessel was operable with the impeller piece wedged between the reactor vessel and the flow skirt.
The licensee concluded that the
cause of the repeated impeller failures was fatigue-related effects from the
operation of the PCPs in conditions beyond the maximum flow rate and below the
minimum net positive suction head recommendations as described in design
documentation. These conditions are present when operating only one or two PCPs
(one on each loop) during reduced temperatures and pressures (i.e., during
startup and shutdown activities). Cyclic pressure pulses and stresses are created
under these reduced pressure conditions that act on the leading edges of the impellers,
which can ultimately lead to impeller vane cracking and the break-off of small impeller
pieces. The licensee determined, based on metallurgical examination of a previous
impeller piece that broke off and the mechanism by which the cracks propagated,
that weld refurbished impellers were particularly susceptible to degradation. At
normal operating temperature and pressure, there is adequate net positive
suction head on all PCPs, so these additional stresses are not present.
The inspectors and NRC staff from
headquarters conducted an in-depth independent review of the analyses forming
the basis for the licensee’s conclusions. The independent review included:
• The licensee’s analytical basis
for why the wedged impeller fragment was expected to remain in place;
• The licensee’s determination
that the impact of the impeller fragment wedged between the reactor vessel and
the flow skirt did not exceed the structural integrity of the vessel wall or
the flow skirt support welds;
• The licensee’s analysis for why
the wedged impeller fragment was not expected to break into smaller pieces and
in the unlikely scenario that it did, the impact of the pieces on fuel cooling,
fuel cladding, and the reactor vessel structure;
• The licensee’s assessment of
the potential for corrosion at the interface of the wedged impeller fragment,
reactor vessel, and flow skirt; and
• The licensee’s assessment of a
worst case scenario accident that could result in the impeller piece impacting
the reactor vessel or affecting fuel integrity
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