***(update) So the NRC and Entergy says they fixed the actuator with the 400 degree vitol seal material. It is much better material and with a high likelihood of accident survivability. It is much better material than the Buna at first blush. But if they put grade B material in for the actuator seals, what about all the rest materials in the valve and actuator? Please list all the grade B material in the SRVs? They were built as a grade B valve, not a grade A valve.
I am strictly a show me man in nuclear power. I want you to put that valve and actuator on a test stand, mimic the duty of severe accident with 400 degrees. I need a positive repeatable test many times and without leaks.
As far as the SRV problems at Peach Bottom, they seemed to have put in 3 stage SRVs their plants. There has not been any new SRV pressure lift test reportable inaccuracies problem since. They had tons of problems in the setpoint lift test with the 2 stage. Generally it is not required public reporting when a SRV leaks. They might not be using their SRVs like Pilgrim for the cooldowns...thus really not cycling them allowing them to see and report a failure to operate.
Forgot-the trajectory of this began as the SRVs actuators seals were first made from asbestos. Asbestos was dangerous and for legal reasons they shifted to silicone seals. Then when they didn’t have a grade A actuator, they went to a grade B actuator with a lower grade seal buna material in it. Then installed 400 degree vitol material. Can you just imagine the fractions of pennies the saved by using the buna.You can destroy the culture of many people having to play words game here.
I wonder if the SRVs problems at Peach Bottom continued.
Originally published on 11/6/12
Now to double check and see if the links work? They are fixed and the last fix of this article happened on Nov 7 at 10:15 am
Right, this grossly rusted picture is from the Vernon Dam emergency power switchyard to Vermont Yankee...we know today the NE Independent System Operator and NRC required them to install a on-site replacement for the dam's capacity with a 4 MW diesel generator before the turn of the year. And VY proposes installing same.
From a nuclear professional, what does this mean?
You notice I submitted my Peach Bottom Petition on Oct 15th and the new Vermont inspection report 2012004 was signed on Oct 31...
You notice I submitted my Peach Bottom Petition on Oct 15th and the new Vermont inspection report 2012004 was signed on Oct 31...
2011008: "During RFO27, Entergy discovered that the SRV Vendor no longer supported the Type-1 SRV actuators which VY had. The vendor recommended replacing the Type 1 actuators with a Type 2 actuator. The Type 1 actuator has silicone thread sealants which are rated up to -390 degrees F while a Type 2 actuator uses BUNA-N polymer which is rated up to 210-250degrees F."
Does this mean only the seal is a type 2, absolutely no. It means the whole actuator is a 225 degree F component. Based on a simpleton nuclear professional assumption, the poor quality at normal temperature and not 400 degree F temperature buna-n critical nuclear safety relief valve should have kicked them into the extent of cause/condition investigation much like the Fort Calhoun recent containment sample valves with 120 degree nitrile elastomers LER (The design temperature limit for the nitrile elastomers used in the valves is 180°F which is acceptable for the normal operating conditions inside Containment of 120°F). Remember the actuator vendor to VY left them out in the blue with no type 1 actuator...I suspect this vendor told all the nuclear plants they supported only type 2 actuator. I am sure the vendor said, tough, or purchase it from somebody else or shutdown. So the VY vendor is: "Parker Hannifin Corporation and dedicated for use in safety class applications by Curtiss-Wright Flow Control Corporation, Target Rock Division."
On the Vermont Yankee SRV actuator LER and within any NRC inspection report on same there is no mention of a "extent of cause/condition investigation" with the SRV seals. This is a fundamental engineering investigatory technique and the missing query indicates fraud and collusion between the NRC and Entergy.
You see the low standards with how corporation's write License Even Reports... notice Exelon-Peach Bottom doesn't mention the vendors name on their Safety Relief Valve air actuators seal failure LER. Did Peach Bottom do a "extent of cause/condition" investigation on their dangerous type two 225 degree F SRV valves that should have been qualified for 400 degrees F. Of course not! This must be collusion and fraud between them all.
They should have commenced, and the NRC show have demanded....an immediate investigation if other components in the actuator were type 2 components...if these other components couldn't withstand 360 degree heat. That would kicked VY into a Fort Calhoun sample valve air actuator extent of cause/ condition investigation per their Licence Event Report and they would had to declare a 10 CFR 50.73(a)(2)(v)(D). Here is the generic version with Fort Calhoun's air actuator quality problems in containment.
"This condition is being submitted pursuant to: , Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident."
I am certain if the NRC knew there was a certain condition where all SRV's would fail in a design accident, that would force VY to immediately shutdown and then get appropriate quality air actuators. And they would have went hunting throughout the industry for dangerous environmentally unqualified less than 225 degrees F actuators and other similar inviromentally unqualified component.
Just to be clear, this is how the NRC speaks to the Vermont Yankee dangerous 225 degree F qualified buna-n SRV that failed at 180 degrees F normal operating temperatures in June 2, 2011 Inspection Report 2011008 for the last time until today's new inspection report.
Just to be clear, this is how the NRC speaks to the Vermont Yankee dangerous 225 degree F qualified buna-n SRV that failed at 180 degrees F normal operating temperatures in June 2, 2011 Inspection Report 2011008 for the last time until today's new inspection report.
"NRC Inspection Report 05000271/2011002 documents an LER closeout review and two Licensee identified Violations related to inoperability of Main Steam Safety Relief Valves (SRVs) due to degraded thread seals. During the 2010 RFO: the pneumatic actuators for the four SRVs were tested and leakage was identified through the shaft-to piston thread seal that was in excess of the design requirement on two of the four SRVs. Material testing determined that the apparent cause of the degraded thread seal condition was thermal degradation. During RFO27, Entergy discovered that the SRV Vendor no longer supported the Type-1 SRV actuators which VY had."
So this is how the NRC explains it today in Vermont Yankee's Inspection Report 2012004
"During the 2009 refueling outage, Entergy found nitrogen to be leaking from the actuators and determined the actuator stem nut seals were degraded. However, Entergy’s evaluation of the seal incorrectly concluded that the seal material was defective and a new Buna-N seal was installed."
This is Entergy-Vermont Yankee explains it is their revised LER 05000271/2010-002-01.
"During the 2010 refueling outage, the actuators for the four main steam (EIIS=SB) safety relief valves (EIIS=RV)RV-2-71 A, B, C & D, were tested and leakage was identified through the shaft to piston thread seal on three of the four RV actuators."
Is there a difference between "shaft to piston thread seal" and "actuator stem nut seal"...why can't the NRC stay with the same wording they used from the first VY LER and NRC inspection reports.
Bottom line after doing a little research, I think the NRC is talking about the same component with the "shaft to piston thread seal" and "actuator stem nuts". I thought it was a completely different new component from yesterday.
But I still think VY should have called a 10 CFR 50.73(a)(2)(v)(D) in the beginning of the SRV seal problem. Those valves are a type 2, remember the vendor cheapskated for pennies savings, installing the buna-n seal into containment. I believe there was, and still are, basically fraud and a cover-up, by knowingly installing environmentally unqualified 225 degree F rubber and plastic parts in the SRV actuators and possible other components. These guys will fail surprisingly fast in any accident that heats up the containment.
....
2nd Petition
Oct 13
Petition On Peach Bottom, VY And Other Unnamed Nuclear Plants
Oct 4
Peach Bottom/Fort Calhoun SRV Seal Questions
*****
1st Petition
Jan 24 then reposted June 11
Emergency Shutdown Of Peach Bottom Over SRV Seals
Feb 01
Peach Bottom SRV Seal Notes
Oct 13
Petition On Peach Bottom, VY And Other Unnamed Nuclear Plants
Oct 4
Peach Bottom/Fort Calhoun SRV Seal Questions
*****
1st Petition
Jan 24 then reposted June 11
Emergency Shutdown Of Peach Bottom Over SRV Seals
Feb 01
Peach Bottom SRV Seal Notes
Vermont Yankee Inspection Reports:
2012004 October 31, 2012
***Nov 6 2012: I am reposting this...originally posted on April 23, 2011
How this bleeds into the new Pilgrim plant inspection report, it almost looks the NRC and I am working behind the scene...
New Nov 8
October 31, 2012
Mr. Christopher Wamser
Site Vice President
Entergy Nuclear Operations, Inc.
Vermont Yankee Nuclear Power Station
Vernon, VT 05354
SUBJECT: VERMONT YANKEE NUCLEAR POWER STATION – NRC INTEGRATED
INSPECTION REPORT 05000271/2012004
2 Annual Sample: Automatic Depressurization System Actuator Leakage
a. Inspection Scope
The inspectors performed an in-depth review of Entergy’s apparent cause analyses and corrective actions associated with the issue of actuator stem leakage on valves in the automatic depressurization system (ADS). Specifically, Entergy identified repeat occurrences of leakage around actuator stems during the 2009 and 2011 refueling outages. The inspectors determined whether Entergy had taken appropriate corrective actions to prevent recurrence of the leakage. Additionally, the inspectors reviewed an operability determination performed during the previous operating cycle following the discovery by Entergy that the seal installed on the ADS actuator stems did not meet environmental qualification requirements.
The inspectors interviewed plant personnel and reviewed test procedure results, condition reports, engineering evaluations, root cause analyses, and manufacturer data to assess Entergy’s problem identification, evaluation, and corrective action effectiveness with respect to the ADS actuator leakage. Specifically, the inspectors reviewed the documents to determine if the seal material used on the ADS actuator stems from 2008 to 2011 should be attributed as the root cause of the 2009 and 2011 stem leakage and to verify that the replacement seal material now installed was qualified for the expected environmental conditions. Additionally, the inspectors reviewed the TS, the UFSAR, and Vermont Yankee licensing documents to assess adverse impact due to the leakage with respect to design basis requirements. Finally, the inspectors evaluated whether the compensatory actions taken by Entergy following identification of the degraded condition provided reasonable assurance of operation of the ADS system during a design basis event and that Entergy’s conclusion that the system remained operable with the degraded condition was correct.
Findings and Observations
No findings were identified.
Entergy modified the actuator system in 2008. However, in consultation with the manufacturer, Entergy incorrectly concluded that the changes to the actuators were “like for like” replacement of components. Entergy failed to determine that the seal material for the actuator stem nut had been changed from Silicon to Buna-N. This change resulted in the temperature rating of the seal dropping from 400 degrees Fahrenheit (F) to 225 degrees F. During the 2009 refueling outage, Entergy found nitrogen to be leaking from the actuators and determined the actuator stem nut seals were degraded. However, Entergy’s evaluation of the seal incorrectly concluded that the seal material was defective and a new Buna-N seal was installed. Entergy performed a subsequent evaluation of the seal material and determined that the material was Buna-N, not defective, and the failure of the material was due to exceeding the thermal rating (225 degrees F) of Buna-N. Following identification that the seal material did not meet environmental conditions, Entergy performed an operability determination which concluded that the ADS system was operable, but degraded. These performance deficiencies were previously evaluated by the NRC in inspection reports 05000271/2011002 and 05000271/2011008.
The ADS system consists of four 3-stage safety relief valves with an actuator attached to the valves so that they can be opened using a nitrogen gas supply. The UFSAR states that nitrogen for the actuation of the valves is stored in accumulators installed in the drywell that are sized to ensure sufficient gas is available for the required number of ADS valve actuations following a design basis accident. This system was credited to respond to design basis accidents and was required to be operable by TS. Additionally, nitrogen bottles were installed outside the drywell to actuate the ADS system following a design basis seismic event. The bottles were sized to allow operators to control reactor pressure using the ADS system for several days following the event. The inspectors determined that this portion of the system had not been evaluated or licensed for design basis accidents other than seismic events.
The inspectors reviewed the evaluations performed by Entergy that assessed past operability of the system prior to the 2011 refueling outage and the operability determination performed during the operating cycle. By crediting the use of the nitrogen bottles, Entergy determined that an adequate nitrogen supply would be available to respond to design basis accidents and events even with the additional loss of inventory from the accumulator stem leakage. Entergy concluded that the ADS system had remained operable because there was adequate nitrogen inventory available. The inspectors questioned whether the bottles and piping would be available for all design basis accidents. In response, Entergy performed an evaluation and concluded the bottle system had been designed to survive the required design basis accidents and would be available. The inspectors reviewed and concurred with the assessment, but noted that the evaluation was not done prior to crediting the system in the 2011 operability determination.
Finally, the inspectors evaluated the corrective action that replaced the Buna-N seal material with Viton®, a flouroelastomer, during the 2011 refueling outage. The inspectors found that this material had the same properties as the previously installed silicon seal,with a temperature rating of 400 degrees F, and met the environmental requirements for the system.
***March 17, 2011
New Nov 8
October 31, 2012
Mr. Christopher Wamser
Site Vice President
Entergy Nuclear Operations, Inc.
Vermont Yankee Nuclear Power Station
Vernon, VT 05354
SUBJECT: VERMONT YANKEE NUCLEAR POWER STATION – NRC INTEGRATED
INSPECTION REPORT 05000271/2012004
2 Annual Sample: Automatic Depressurization System Actuator Leakage
a. Inspection Scope
The inspectors performed an in-depth review of Entergy’s apparent cause analyses and corrective actions associated with the issue of actuator stem leakage on valves in the automatic depressurization system (ADS). Specifically, Entergy identified repeat occurrences of leakage around actuator stems during the 2009 and 2011 refueling outages. The inspectors determined whether Entergy had taken appropriate corrective actions to prevent recurrence of the leakage. Additionally, the inspectors reviewed an operability determination performed during the previous operating cycle following the discovery by Entergy that the seal installed on the ADS actuator stems did not meet environmental qualification requirements.
The inspectors interviewed plant personnel and reviewed test procedure results, condition reports, engineering evaluations, root cause analyses, and manufacturer data to assess Entergy’s problem identification, evaluation, and corrective action effectiveness with respect to the ADS actuator leakage. Specifically, the inspectors reviewed the documents to determine if the seal material used on the ADS actuator stems from 2008 to 2011 should be attributed as the root cause of the 2009 and 2011 stem leakage and to verify that the replacement seal material now installed was qualified for the expected environmental conditions. Additionally, the inspectors reviewed the TS, the UFSAR, and Vermont Yankee licensing documents to assess adverse impact due to the leakage with respect to design basis requirements. Finally, the inspectors evaluated whether the compensatory actions taken by Entergy following identification of the degraded condition provided reasonable assurance of operation of the ADS system during a design basis event and that Entergy’s conclusion that the system remained operable with the degraded condition was correct.
Findings and Observations
No findings were identified.
Entergy modified the actuator system in 2008. However, in consultation with the manufacturer, Entergy incorrectly concluded that the changes to the actuators were “like for like” replacement of components. Entergy failed to determine that the seal material for the actuator stem nut had been changed from Silicon to Buna-N. This change resulted in the temperature rating of the seal dropping from 400 degrees Fahrenheit (F) to 225 degrees F. During the 2009 refueling outage, Entergy found nitrogen to be leaking from the actuators and determined the actuator stem nut seals were degraded. However, Entergy’s evaluation of the seal incorrectly concluded that the seal material was defective and a new Buna-N seal was installed. Entergy performed a subsequent evaluation of the seal material and determined that the material was Buna-N, not defective, and the failure of the material was due to exceeding the thermal rating (225 degrees F) of Buna-N. Following identification that the seal material did not meet environmental conditions, Entergy performed an operability determination which concluded that the ADS system was operable, but degraded. These performance deficiencies were previously evaluated by the NRC in inspection reports 05000271/2011002 and 05000271/2011008.
The ADS system consists of four 3-stage safety relief valves with an actuator attached to the valves so that they can be opened using a nitrogen gas supply. The UFSAR states that nitrogen for the actuation of the valves is stored in accumulators installed in the drywell that are sized to ensure sufficient gas is available for the required number of ADS valve actuations following a design basis accident. This system was credited to respond to design basis accidents and was required to be operable by TS. Additionally, nitrogen bottles were installed outside the drywell to actuate the ADS system following a design basis seismic event. The bottles were sized to allow operators to control reactor pressure using the ADS system for several days following the event. The inspectors determined that this portion of the system had not been evaluated or licensed for design basis accidents other than seismic events.
The inspectors reviewed the evaluations performed by Entergy that assessed past operability of the system prior to the 2011 refueling outage and the operability determination performed during the operating cycle. By crediting the use of the nitrogen bottles, Entergy determined that an adequate nitrogen supply would be available to respond to design basis accidents and events even with the additional loss of inventory from the accumulator stem leakage. Entergy concluded that the ADS system had remained operable because there was adequate nitrogen inventory available. The inspectors questioned whether the bottles and piping would be available for all design basis accidents. In response, Entergy performed an evaluation and concluded the bottle system had been designed to survive the required design basis accidents and would be available. The inspectors reviewed and concurred with the assessment, but noted that the evaluation was not done prior to crediting the system in the 2011 operability determination.
Finally, the inspectors evaluated the corrective action that replaced the Buna-N seal material with Viton®, a flouroelastomer, during the 2011 refueling outage. The inspectors found that this material had the same properties as the previously installed silicon seal,with a temperature rating of 400 degrees F, and met the environmental requirements for the system.
***March 17, 2011
Executive Director for Operations
US Nuclear Regulatory Commission
Washington, DC 20555-0001
Subject 2.206: Request a emergency shutdown of Vermont Yankee because the Reactor Oversight Program is ineffective and Entergy has a documented history of a culture of falsification and thumbing their noses at reoccurring violations. It should be noted in this inspection period most of the fleet of Entergy’s plants are on fire and burning in the Gulf of Mexico with numerous NRC inspection findings including Palisades, Grand Gulf, River Bend, Arkansas One and Cooper.
Dear Mr. Borchardt,
In the 1942 movie Casablanca:
Rick Blaine: How can you close me up? On what grounds?Jan 18, 2011: My 2.206 Emergency Shutdown of Vermont Yankee
Captain Louis Renault: I'm shocked, shocked to find that gambling is going on in here.
“The safety culture of the plant is impaired because of information inaccuracies and wide spread acceptance of falsifications.”Inoperability of Main Steam Safety Relief Valves due to Degraded Thread Seals (Licensee Event Report 05000271/2010-002-01)
“I request Vermont Yankee to be immediately be shut down and that Entergy be prohibited from owning nuclear power plants... because Entergy doesn’t have the integrity to tell the truth about safety and nuclear power plant issues. Money and profits comes before truth telling and full disclosures.”
"During the 2010 refueling outage, the actuators for the four main steam safety relief valves , were tested and leakage was identified through the shaft to piston thread seal on three of the four RV actuators. This leakage, when combined with the RV accumulator leakage, caused two of the four RVs to not meet design actuation requirements. The nitrogen gas is introduced from an accumulator assembly which contains enough gas for two operations at 70% of containment design pressure or approximately five operations at atmospheric pressure...and it is critical for the low pressure core cooling system to work."These relief valves are the devices used to control pressure in the Fukushima plant meltdowns and they had a terrible time maintaining pressure protection during their accident. They had to operate these valves multiple times and all these valves had is the accumulators and no electricity after the safety batteries wore down. You know that outside nitrogen supply was severed be quickly after the accident.
"The thread seals were manufactured in 2002, supplied to Vermont Yankee (VY) in new style actuators in 2008 and were in service for one operating cycle prior to the test."They were in there less that 2 years and they don't know if they became dysfunctional within month of heated operation.
"The thread seals in the new style actuators are made of Buna-N material, were manufactured by Parker Hannifin Corporation and dedicated for use in safety class applications by Curtiss-Wright Flow Control Corporation, Target Rock Division. Prior to the upgrade to the new style actuators, the thread seals were made from a silicon material. Material testing determined that the apparent cause of the thread seal condition was thermal degradation. The change to use Buna-N material in the new style seal resulted in reduced thermal margin when considering the potential local heat transfer affects on the seal material. The use of silicone material in the original application provided more margin."This is atrocious behavior for nuclear safety engineers... they substituted Buna-N material for silicone and they weren’t aware of the properties of the Buna-N material or considered for the heated environment? There must be a testing regime to assure the Buna-N material would survive the heated environment before it was used in the plant....how did that fail? This is a object organizational safety related failure of Quality Assurance and Quality Control. Entergy has construction related QA/QC problem and now it is showing up in the nuclear safety end? It is interesting, the NRC suspects QA/QC problems at the plants and they still allow VY to operate without a all clear signal that it isn't known and corrected. It questions their safety related spare or replacement parts purchase programs...in that they can’t maintain the quality of nuclear grade safety components. It questions, in a widespread manner, if they are substituting inferior replacement parts in all their safety components. How many inferior safety related replacement parts are there in the Vermont Yankee?
This event did potentially affect the ability of the RVs to perform their manual and automatic ADS function since the combined thread seal leakage and accumulator leakage impacted the ability of the RVs to satisfy design actuation requirements. However, due to the redundancy in the ADS design, the availability of the HPCI system and availability of backup nitrogen supplies, the ability to depressurize the reactor was maintained.Unbelievable, they knowingly started up with inferior critical nuclear safety parts and they had evidence Buna-N would degrade and fail. I bet you they were gaming uncertainty, we got no proof of the Buna-N has failed yet...so we can start up. I‘ll bet they knew the Buna-N was inappropriate, didn’t have on site the appropriate silicone, so they intentionally started up knowing the part would fail between outages.I bet you they could tell by feel the buna-n was degraded. I’ll bet you the manufacture no longer made this obsolete replacement part. How much sense does it take when the material was in for the first time, it failed, it is common sense it was the new material that bad. Thus is absolutely contemptuous of the design function...that their other systems make this a nothing incidence. They should be thinking this system that can’t stand any unknowns...they should be considering this a last ditch system and assume everything else is broken.
VY will replace the Buna-N thread seal material in all four RVs during the 2011 refueling outage with a material that provides more temperature margin. This event did potentially affect the ability of the RVs to perform their manual and automatic ADS function since the combined thread seal leakage and accumulator leakage impacted the ability of the RVs to satisfy design actuation requirements. However, due to the redundancy in the ADS design, the availability of the HPCI system and availability of backup nitrogen supplies, the ability to depressurize the reactor was maintained.
1) This should make you absolutely sickened, they know it’s the wrong material, they knows it fails within the first cycle...and they stuck the same defective material in there knowing the plant won’t meets its Fukushima requirements.
2) Request Vermont Yankee immediately shutdown and they replace there relief valve o ring Buna-N material with silicone. The is the shuttle Challenger accident all over again. Request Vermont Yankee nuclear power plant and all Entergy nuclear power plants be immediately shutdown.
4) Request a outside the NRC investigation of this NRC behavior for tolerating this atrocious regulatory behavior.
5) Request top Vermont Yankee Management staff be fired and replaced before startup.
6) Request Entergy’s corporate nuclear senior staff be fired and replaced before the restart of the plants.
...7) Request the formation of a local public oversight panel around every nuclear plant.
...8) Request a emergency NRC senior official oversight panel with the aims of
reforming the ROP.
...9) Request a national NRC oversight panel of outsiders to overseer and report on the agency’s activities. There should be a mixture of professional academic people and capable lay people.
10) There is some heavy duty and exceedingly numerous findings of problems with Entergy plants’ this inspection reporting cycle...do an analysis of why this is occurring.
Sincerely,
Mike Mulligan
Hinsdale, NH
1-603-336-8320
steamshovel2002@yahoo.com
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