Big picture my analysis goes like this. I have been studying this for many years.
The NRC won’t disclose what is driving this because it will threaten a tremendous
amount of grid electricity across many plants. The industry got themselves
backed into a corner. Just think about it, why would these modern corporations tolerate
this? These SRVs threatens blowing a lot money, unproductively eating up a lot
of resources…another industry would just clear off the decks with bringing on
modern equipment. They just get rid of their unproductive headaches and risk. So
obviously they are stuck with the SRVs until permanent shutdown. Target Rock and
Areva can’t provide SRVs to the USA because of the financial risk with getting
blamed with their valves causing a meltdown. They could get sued over many tens
of billions of dollars of damages. So where is the governmental insurance if
one of their valves caused enormous financial damages? This just might be the
result of Fukushima. Remember overheated SRVs, components like valve rubber
seals and electrical cable caused the valves to get stuck stuck shut. This primarily caused the meltdown
and release of radioactivity. The footprint of Fukushima would have been drastically smaller if the valves were opened. I wonder who supplied the SRVs to Fukushima?
Behind Hope Creek’s SRV problems is they can’t get any legitimate corporation
to produce and supply SRVs to these old BWRs. The Corporations are stuck using
bailing wire and duct tape (Chinese parts) to keep their SRV operable until permanent
shutdown. That is the cover-up.
UNITED
STATES
NUCLEAR
REGULATORY COMMISSION
REGION I
2100
RENAISSANCE BLVD., SUITE 100
KING OF
PRUSSIA, PA 19406-2713
December 31, 2015
Mr. Michael Mulligan
P.O. Box 161
Hinsdale, NH 03451
Dear Mr. Mulligan:
I am replying to your calls and emails with Richard Barkley of my
staff in November 2015. At that time, you expressed concerns with the as-found
test results over the last several years of the two-stage Target Rock safety
relief valves (SRVs) installed at Hope Creek. As Mr. Barkley discussed with
you, the NRC has been aware of this problem for some time as documented in prior
NRC resident inspection reports (e.g., see integrated inspection report
50-354/2013-005). PSEG has reported these issues in LERs for Hope Creek in 2012,
2013 and 2015, and
(Note: the indented material is my add on...this isn't on their letter to me.)
(Note: the indented material is my add on...this isn't on their letter to me.)
total of ten of the 14 SRV pilot stage assemblies had setpoint drift outside of the required TS 3.4.2.1 tolerance values of +/-3% of nominal value.
as-found' test results for the ten SRVs not meeting the TS requirements are as follows:
Valve ID As Found TS Lift Setting Acceptable Band % Difference
(psig) (psig) (psig) Actual
F013C 1216 1130 1096.1 -1163.9 7.61%
F013F 1240 1108 1074.8 -1141.2 11.90%
F013G 1208 1120 1086.4 - 1153.6 7.86%
F013H 1148 1108 1074.8-1141.2 3.60%
F013J 1161 1120 1086.4 -1153.6 3.66%
F013K 1161 1108 107 4.8 -1141.2 4.80%
F013 L 1165 1120 1086.4 -1153.6 4.00%
F013 M 1207 1108 1074.8 -1141.2 8.90%
F013P 1221 1120 1086.4 -1153.6 9.00%
F013R 1169 1120 1086.4 -1153.6 4.38%
A total of five of the 14 SRV pilot stage assemblies had setpoint drift outside of the required TS 3.4.2.1 tolerance values of +/-3% of nominal value. On November 4, 2013, HCGS received a report documenting the failure of SRV 'L.' On November 22, 2013, HCGS received a second report documenting the failures of SRVs 'A', 'D', 'F', and 'K.'
Valve ID As Found TS Lift Setting Acceptable Band % Difference
(psig) (psig) (psig) Actual
F013A 1170 1130 1096-1163 3.5%
F013D 1192 1130 1096-1163 5.5%
F013F 1178 1108 1075-1141 6.3%
F013K 1149 1108 1075-1141 3.7%
F013L 1175 1120 1087-1153 4.9%
The cause of the failure of solenoid valve (S/N 481) was determined to be a manufacturer's assembly error. The external vendor found that the anti-rotation pin that secures the adjustable plunger was not installed. Without the pin, the plunger was allowed to rotate and unthread until contacting the internal stop, which prevented the solenoid from picking up when energized. The solenoid coil was in good condition; there was no indication of an internal short. The SOV was reassembled with the plunger re-threaded in place. With the valve body installed back on the solenoid, the SOV could be operated. HCGS determined from the results of the failure analysis that the failure of this SOV occurred at some point during the operating cycle.
A total of six of the 14 SRV pilot valves experienced setpoint drift outside of the TS 3.4.2.1 limit.
Five of the six SRVs were within the maximum allowable percent increase (MAPI) value. The SRV-F was the only SRV that did not meet the MAPI value. A Technical Evaluation assessed whether the stresses imposed by the increased lift setpoint would have been below the ASME Section III, Appendix F value for failure. The results of the Technical Evaluation are being communicated in this supplemental LER.
(psig) (psig) (psig) Actual Limit
F013B 1169 1130 1096-1163 3.50% 39.4%
F013F 1193 1108 1075-1141 7.70% 5.5%
F013H 1157 1108 1075-1141 4.40% 37.7%
F013K 1202 1108 1075-1141 8.50% 22.40%
F013L 1193 1120 1087-1153 6.50% 16.30%
F013P 1185 1120 1087 -1153 5.80% 27.4%
following several refueling outages prior to that time.
During the resident inspectors’ closeout inspections of the LERs issued by Hope
Creek for the as-found setpoint drift of the SRVs, it was noted that PSEG
engineering evaluations determined that the reactor vessel overpressure
protection was not affected by the SRV pilot valve setpoint drift. Thus the SRVs
were capable of performing their design safety function even with the setpoint
drift noted. In addition, the increase in mechanical stresses on the torus and
torus attached piping due to the higher lift setpoints remained within code
acceptable limits. These LER closeouts and the inspectors’ independent assessment
of the safety significance of these events were documented in NRC integrated inspection
reports 2012-005 and 2014-003.
The issue of setpoint drift as well as the reliability for Target Rock
two and three stage safety relief valves installed in Boiling Water Reactors
has been of concern to the NRC for many years, and was the subject of Generic
Safety Issue B-55, “Improved Reliability of Target Rock Safety Relief Valves.”
The resolution of that GSI was published in Regulatory Issue Summary (RIS) 2000-012,
a copy of which is available on the NRC
Right, Regulatory Issue Summary 2000-012 is severely obsolete... information at least sixteen year old. Why can't they keep up to industry problems. Where is there a new report on these problems. The stellite and platinum information is also old old information too. The facts are, after putting stellite and platinum in plant, the condition only worsened. All these NRC officials are professional word smiths and highly educated. Why is the agency intentionally fuzzing up the picture they are giving us.
website. As noted in that RIS, several actions
were taken by the BWR Owners Group and individual BWR licensees to improve the performance
of Target Rock SRVs. These actions included: (1) the installation of ion beam implanted
platinum or Stellite 21 pilot valve disks, and (2) the installation of
additional pressure actuation switches. These changes, coupled with an expanded
acceptance range (from +/- 1% to +/- 3%) for SRV setpoint as-found values, have
significantly reduced the number of SRV asfound setpoints being outside the
specified Technical Specification limit. However, as noted in NRC Information
Notice 2006-024 (ML062910111), during offsite vendor testing following refueling
outages, SRVs continue to be found with lift setpoints outside the tolerances
required by the Technical Specifications for Hope Creek and a number of other
BWRs.
In the
particular case of Hope Creek, PSEG has taken steps to improve SRV performance,
specifically the installation of ion beam implanted platinum or Stellite 21
pilot valve disks, but with limited success to date. PSEG’s prior long-term
plan to address setpoint drift was to install SRVs from a foreign vendor that
had demonstrated better setpoint performance over time.
Unfortunately,
that vendor was not able to meet the performance specifications set by PSEG and
that plan was abandoned. PSEG then proposed replacing their two-stage Target
Rock SRVs with three-stage Target Rock SRVs due to the three-stage valve
performance history of less setpoint drift over time. That plan was suspended
shortly before the last refueling outage when another plant in the industry
experienced performance issues with the opening of their three stage SRVs and
subsequent failure to promptly reclose. Going forward, the NRC plans to
continue monitoring and independent oversight of the performance of Hope Creek’s
SRVs consistent with the NRC’s Reactor Oversight Process (ROP).
We
appreciate your concerns in this matter and recognize that the setpoint drift
experienced by the SRVs at Hope Creek continues to recur in spite of prior
corrective actions by PSEG. Consistent with ROP guidance and the safety
significance of the issue, the NRC will continue to focus inspection resources
on this issue to ensure effective, long-term corrective actions are taken by
PSEG. Should you have any further questions in this matter, please contact
Richard Barkley of my staff at (610) 337-5328.
Sincerely,
/RA/
Fred L.
Bower, III, Chief,
Projects
Branch 3
Division
of Reactor Projects
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