I panicked Entergy- Pilgrim into writing the content of the new LER
The NRC is a severely dishonest United States Of America federal agency!
April/May 2011: New SRV valves installed.
*Nov 25, 2011 (disclosed on April 18, 2013) second small leak on SRV RV-203-3C
Dec 26, 2011: First Pilgrim plant leak, shutdown and 3 day shutdown. Replaced SRV RV-203-3D per LER 2013
*RV 203-3C on this shutdown per LER 2013-002-00
*Jan 20, 2013: Second leak, required shutdown and another 3 day shutdown. ("On Sunday, January 20, 2013, at 2050 hours, the station entered a 24-hour action statement...)
Jan 21, 2013: NE ISO asserts grid emergency, near mandatory rolling black outs in really cold winter weather (NH Union Leader).
Jan 24, 2013: NE ISO says natural gas shortage began in earnest with $300 megawatt-hour(NH Union Leader).
Jan 2013: Peak demand this year 20,800 megawatt, overall peak demand of 22, 818 megawatt (NH Union Leader).
Feb 3, 2013: Third leak, restricted to 80-84% power to control leak.
Feb 6, 2013: Pilgrim admitted leaking media.
*Feb 8, 2013: Nemo blizzard strikes, plant trip, two LOOPs, and just repair and replace of one SRV.
Feb 9, 2013: NE ISO says grid crisis developed during the early morning hours of the blizzard...gas generators couldn't get gas from the market (NH Union Leader).
Feb 13,2013: My Peach Bottom presentation to the NRC and Exelon. I always had issues with coloring within the lines with my crayons.
"This is a Hurricane Katrina. This is a Hurricane Sandy. This is a Blizzard Nemo that's coming down on you guys..."Feb 14, 2013 NRC senior project manager discussion with Entergy-Vermont Yankee worrying VY may no longer be financially qualified to operate a nuclear plant.
"This is a climate change. This is a huge economic climate change that's going on in the industry as far as this natural gas business..."
Feb 15, 2013: NYT's article 'The Natural Gas Trap' and $130 megawatt-hour prices all month long.
Feb 16, 2013: Start-up from blizzard trip.
*Feb 26, 2013: New leak develops and restricted to 94% power to control leaks.
*March 13, 2013: Submitted my Pilgrim SRV request for emergency shutdown on March 13, 2013.
March 17, 2013: NH Union Leader article 'Reliance On Natural Gas A Threat To The Grid'.
March 21, 2013: Still leaking and NRC is questioning the financial qualifications of Vermont Yankee.
March 30, 2013: Power restricted to 85%. We don't know if the leak got worst or an addition SRV is leaking, or something else.
*Added April 19, 2013
April 11, 2013: My Pilgrim Safety Relief Valve NRC Petition.
April 14, 2013: Pilgrim had difficulties with shutdown for refueling.
April 18, 2013: Feb 20, 2013 SRV leak and plant shut down LER 2013-02-001
1) Get a load of the title: SRV-3B Safety Relief Valve Declared Inoperable Due to Leakage and Setpoint Drift
2) March 18, 2013: Entergy's LER 2013-02-00 date of submittal is March 21, 2013.
3) Event date: Jan 20, 2013 per Entergy
4) Submitted my Pilgrim SRV request for emergency shutdown on March 13, 2013.
4) Reported date: March 21, 2013 per Entergy
5) Pilot
S/N SRV Position As-Found Deviation
23 RV-203-3B 1112 psig (-)3.8%6) This LER disclosed:
a) First small SRV leak on May 18, 2011 (SRV RV-203-3C)
b) Second small leak on Nov 25, 2011 (SRV RV-203-3C)
c) Shutdown on Jan 26, 2013 RV- 203-3DRV- 203-3D
SRV-3B Safety Relief Valve Declared Inoperable Due to Leakage and Setpoint Drift
On Sunday January 20, 2013, at 2050 hours with the reactor at 100% core thermal power (RMSS in RUN), PNPS declared SRV-3B inoperable and entered Technical Specification (TS) 3.6.D.2 that requires with an SRV inoperable to initiate an orderly reactor shutdown such that reactor coolant pressure is less than 104 psig within 24 hours. On Monday January 21, 2013, at 1300 hours (16 hrs and 10 minutes) reactor coolant pressure was less than 104 psig. SRV-3B was declared inoperable consistent with PNPS procedures that state an SRV is inoperable if the first stage pilot thermocouple temperature is 350 F below its baseline temperature.
The reactor was depressurized and a new pilot valve assembly was installed on SRV-3B. On January 22, 2013, at 1015 hours reactor restart was commenced. On January 24, 2013 at 0312 hours 100% core thermal power was achieved.
This LER also reports the as-found setpoint of one SRV pilot valve tested was less than the minimum
pressure required by TS 3.6.D.1.
This event had no impact on the health and/or safety of the public.
As background, pressure relief system includes four (4) SRVs and two (2) spring safety valves (SSVs).
During Refueling Outage (RFO-18), in April/May, 2011, the four SRVs were replaced with Target Rock Model 0867F 3-stage SRVs. The SRVs discharge through their individual discharge piping, terminating below the minimum suppression pool (torus) water level. The four SRVs are installed on the main steam piping in containment between the reactor pressure vessel and the flow restrictors.
Each 3-stage SRV contains a pilot (also called the first stage), a second stage, and a main stage and an air operator. The main stage contains the steam discharge path, the second stage consists of second stage pilot valve, and the first stage consists of pilot valve with surrounding bellows.
To monitor these valves for leakage, Pilgrim installed thermocouples at the pilot (first stage), at the second stage, on the tailpipe near the valve (4.5' to 6' away), on the tailpipe far from the valve (-20' away) and at the pilot bellows. Procedure 2.2.23, "Automatic Depressurization System", provides guidance for interpreting the thermocouple data and determining valve operability based in part on testing performed by Target Rock.
Subsequent to installation in RFO-1 8 and prior to this event, Pilgrim experienced minor second stage pilot valve leakage from SRV RV-203-3C on May 18, 2011 and November 25, 2011. Also, on December 26, 2011, SRV RV- 203-3D first stage pilot valve experienced leakage while operating at full power. The SRV was declared inoperable and the plant was shutdown on December 26, 2011 in accordance with TS 3.6.D.2 and RV-203-3C was replaced entirely, and the RV-203-3D pilot assembly was replaced (LER 2011-007-00).
EVENT DESCRIPTION:
On Sunday January 20, 2013, at 2050 hours with the reactor at 100% core thermal power (RMSS in RUN), PNPS declared SRV-3B inoperable and entered Technical Specification (TS) 3.6.D.2 that requires with an SRV inoperable to initiate an orderly reactor shutdown such that reactor coolant pressure is less than 104 psig within 24 hours. On Monday January 21, 2013, at 1300 hours (16 hrs and 10 minutes) reactor coolant pressure was less than 104 psig. SRV-3B was declared inoperable consistent with PNPS procedures that state an SRV is inoperable if the pilot stage thermocouple temperature is 350 F below its baseline temperature.
While at full power, indication of a steam leak across the first stage pilot of RV-203-3B was identified. The leakage was evaluated and in accordance with criteria specified in procedure 2.2.23, specifically, if the pilot stage thermocouple temperature is 35 degrees F below its baseline temperature (with a smaller decrease at the second stage thermocouple) and cannot be explained by a corresponding downpower, the SRV is inoperable.
The safety relief valve was subsequently declared inoperable and the Limiting Condition for Operation (LCO) for Technical Specification (TS) 3.6.D.2 was entered. Per TS 3.6.D.2 the plant was shutdown and reactor coolant pressure below was 104 psig within 24 hours.
CAUSE:
The SRVs were purchased new, installed, and tested for the first time in April/May 2011 during RFO-18.
Entergy and Target Rock personnel are currently evaluating the SRV failure events and setpoint drift to determine the root cause and contributing causes.
At this time three (3) separate pilot assemblies which had indications of leakage while installed, have been tested and dissembled at Wyle Laboratory. Thus far, a definitive root cause has not been established. A supplemental report with additional casual analysis is projected to be submitted on September 30, 2013.
EXTENT OF CONDITION:
This condition potentially applies to all four three stage SRVs that were installed in RFO 18. During Cycle 19 operation, Pilgrim observed leakage from RV-203-3B, 3C, and 3D, which is being evaluated as part of the ongoing root cause evaluation.
* On May 18, 2011 and November 25, 2011, SRV RV 203-3C second stage pilot valve minor leakage was observed. SRV RV-203-3C was replaced during the December 26, 2011 shutdown.
*On December 26, 2011, SRV, RV-203-3D first stage pilot valve experienced leakage that exceeded the operability criteria while operating at full power. Plant was shutdown as required by TS 3.6.D.2, RV 203-3C and 3D were repaired and the plant returned to full power operation.
* On January 20, 2013, Pilgrim experienced the event described in this Licensee Event Report, first stage pilot valve leakage of SRV, RV-203-3B. The plant was shutdown as required by TS 3.6.D.2. The pilot valve was replaced with a refurbished pilot and the plant was returned to full power operation.
* On February 3, 2013, RV-203-3B first stage pilot valve leakage was identified while at full power.
Reactor power was lowered to 80% and at 1000 psig pressure, the pilot was reseated. An Operability
Determination with a compensatory measure was implemented to maintain the reactor power at 80%
and reactor pressure at 1000 psig. An Operations Decision Making Issue (ODMI) was implemented to monitor and take corrective actions. During the forced outage on February 8, 2013, caused by a loss of offsite power due to a major winter storm, RV-203-3B first stage pilot valve was replaced with a new pilot valve and the plant was returned to power operation. The removed RV-203-3B pilot valve was sent to Wyle Laboratory for testing.
As-found test results for the SRV, RV 203-3B pilot valve were: Pilot S/N SRV Position As-Found Deviation 23 RV-203-3B 1112 psig (-)3.8%
Technical Specification 3.6.D.1 requires the as-found setpoint to be within 1155±34.6 psig (1120.4 psig to 1189.6 psig). The as-found setpoint was less than the minimum pressure specification required by TS 3.6.D.1. This test result was entered into the corrective action program as a separate event, and is included in this LER since the condition was discovered within 60 days from the initial discovery of pilot leakage. Accordingly, this as-found value being out of Technical Specification setpoint is reported in this LER pursuant to 10 CFR 50.73(a)(2)(i)(B).
CORRECTIVE ACTIONS:
The following corrective actions were completed to address this event related to leaking RV-203-3B.
The first stage pilot valve of RV-203-3B was removed. A new pilot from another valve assembly which was verified to meet set pressure and leakage criteria was installed during the February 8, 2013 loss of offsite power outage.
Additional corrective actions will be implemented based upon the results of the testing, inspection, and evaluation of the leaking first stage pilot from RV-203-3B and other SRV failures by a joint team of Target Rock and Entergy Engineering. Additional corrective actions will be documented in the supplement report referenced earlier.
SAFETY CONSEQUENCES:
The leaking SRV pilot valves and the plant shutdown to repair the SRV in accordance with Technical
Specification 3.6.D.2 posed no threat to the public health and safety.
All leakage from the valve was collected in plant systems, the suppression pool (torus), and processed in accordance with normal station practices.
Pilgrim installed temperature monitoring to provide sufficient indication of SRV leakage to ensure that timely actions can be taken to ensure that the plant is maintained in a safe condition. Procedure 2.2.23 provides the instructions and guidance for interpreting and responding to SRV temperature indications. Based on these instructions, the plant was shutdown. The SRV would have been able to respond if needed to meet its core cooling or reactor pressure vessel over protection functions prior to leakage developing. As a result, the plant safety was maintained. The risk of operating with a leaking SRV is characterized by an increased chance of having an inadvertently opened SRV with increased chance of that valve failing to reclose. Assuming the plant operated for 24 hours with this condition, this results in a change in core damage frequency of less than 1.0E-7. The impact of setpoint drift (0.8% below the 3% tolerance) is considered to be bounded by delta change in core damage frequency of less than 1.OE-7.
PREVIOUS EVENTS:
Prior to Cycle 19, there were no leakage or setpoint drifts occurrences with three stage safety relief valves since all four valves were newly installed in April/May, 2011, during Refueling Outage 18.
During Cycle 19, Pilgrim observed minor leakage from the second stage pilot valve of RV-203-3C. Also, first stage pilot valve leakage was observed from RV-203-3D which was confirmed, plant was shutdown as required by TS 3.6.0.2, and first stage pilot valve was replaced. This event is described in LER 2011-007-00. During the outage for RV-203-3D, the entire RV 203-3C was replaced with a new valve assembly.
The industry has experienced numerous instances where SRV leakage has occurred at other plants with other Target Rock Model three stage safety relief valves OE33766 - Three Stage Safety Relief Valve Pilot Leakage just below Normal Operating Pressure - Plant Hatch.
The plant Hatch installed the same model 3-stage SRVs in Unit 2 in April 2011. Hatch experienced numerous pilot leaks during 2011. On some occasions, leakage was reduced by power and/or pressure reductions. Hatch Unit 2 had some success through power and/or pressure reductions and operating for several months after reseating the first stage pilot valve through power and/or pressure reductions.
OE26394 & OE26892 - Planned Shutdown due to a three stage Safety Relief Valve Leak - Peach Bottom Unit 3
OE32805 - Safety Relief Valve Temperature Phenomenon - Fitzpatrick
OE34730 - Target Rock 3 Stage Main Steam SRV Bore to Seat Misalignment - Limerick 2
OE19219 - Plant Shutdown Due to Increasing Tailpipe Temperature - Duane Arnold
April 19: So operational problems and operator safety determinations issues for safety relief valves and pilot operating relief valves are metastasizing throughout the nuclear industry.
April 11, 2013
SUBJECT: MILLSTONE POWER STATION – NRC INTEGRATED INSPECTION REPORT 05000336/2013002 AND 05000423/2013002
Description. In October 2012, during the Unit 2 refueling outage, Dominion overhauled the ‘B’ PORV because of seat leakage during the operating cycle. Work order 53102395511 specified the following PMTs: PORV stroke time IST, normal pressurizer vent path verification and PORV position IST, and PORV functional test. The stroke time test was performed on October 21 in Mode 6 and the vent path verification and PORV position test was performed on November 11 in Mode 5, but the functional test was not performed prior to entering Mode 3 on November 15. TS 3.4.3 requires both PORVs to be operable in Mode 3. Dominion entered Mode 4 on November 16 at 08:10 to rework the PORV due to seat leakage.
The inspectors questioned why the PORV function test had not been performed prior to entering Mode 3. The primary plant senior reactor operator who determined the post maintenance testing requirements for the PORV repair, put a restraint on the work order indicating that hot functional test had to be performed prior to Mode 2 since the surveillance requirement stated that the PORV had to be stroked at conditions representative of Mode 3 or 4. The shift manager was unaware of the PMT requirement. His concern at the time was low temperature overpressure protection and determined that the stroke time test and vent path verification tests, which were performed under cold plant conditions, were sufficient to demonstrate operability. The inspectors
disagreed with the shift manager’s determination based on Generic Letter 90-06 which stated that testing of the PORVs in HOT STANDBY (Mode 3) or HOT SHUTDOWN (Mode 4) was required in order to simulate the temperature and pressure environmental effects on the PORV. The inspectors concluded that Dominion’s PMT was inadequate because it did not demonstrate the valve’s capability to stroke under all operating conditions prior to entering Mode 3.
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