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#REDIRECT [[RA-17-051, LER 16-005-01 for Oyster Creek Regarding Supplemental Technical Specification Prohibited Condition Caused by One Electromatic Relief Valve Inoperable for Greater than Allowed Outage Time]]
| number = ML18037A091
| issue date = 09/22/2017
| title = LER 16-005-01 for Oyster Creek Regarding Supplemental Technical Specification Prohibited Condition Caused by One Electromatic Relief Valve Inoperable for Greater than Allowed Outage Time
| author name = Gillin M
| author affiliation = Exelon Generation Co, LLC
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000219
| license number = DPR-016
| contact person =
| case reference number = RA-17-051
| document report number = LER 16-005-01
| document type = Letter, Licensee Event Report (LER)
| page count = 5
}}
 
=Text=
{{#Wiki_filter:Exelon Generation
@ RA-17-051 September 22, 2011 U.S. Nuclear Regulatory Commission Attn: Document Control Desk or 0-881 One White Flint North 11555 Rockville Pike Rockville, MD 20852 Oyster Creek Nuclear Generating Station Renewed Facility Operating License No. DPR-16 NRC Docket No. 50-219 Oyster Creek Route 9 South P.O. Box 388 Forked River, NJ 08731 10 CFR 50.73
 
==Subject:==
 
Supplemental Licensee Event Report (LER) 2016-005-01, "Technical Specification Prohibited Condition Caused by One Electromatic Relief Valve Inoperable for Greater than Allowed Outage Time." Enclosed is LER 2016-005-01 reporting the Technical Specification prohibited condition due to an Electromatic Relief Valve inoperable for greater than the allowed outage time discovered during as-found
: testing, which occurred on September 19, 2016. The LER was revised to add supplemental information as required by Revision 00 of the document.
This event did not affect the health and safety of the public or plant personnel.
This event did not result in a safety system functional failure. There are no regulatory commitments made in this LER submittal.
Should you have any questions concerning this report, please contact Gary Flesher, Regulatory Assurance
: Manager, at (609) 971-4232.
Respectfully, Michael Gillin Plant Manager Oyster Creek Nuclear Generating Station
 
==Enclosure:==
 
NRC Form 366, LER 2016-005-01 cc: Administrator, NRC Region I NRC Senior Resident Inspector
-Oyster Creek Nuclear Generating Station NRC Project Manager -Oyster Creek Nuclear Generating Station NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES:
10/31/2018 (06-2016) Estimated burden per response to comply wilh this mandatory collection request 80 hours. Reported lessons learned are incorporated into the licensing process and fed back to industry. : (i i LICENSEE EVENT REPORT (LEA) Send comments regarding burden estimate to the FOIA, Privacy and Information Collections
\. r/j Branch [T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail (See Page 2 for required number of digits/characters for each block) to lnfocoMects.ResourceOnrc.gov, and to the Desk Officer, Office of lnfoITTlation and Regliatory
..... Affairs, NEOB-10202, (315().0104),
Office ol Management and Budget, Washington, DC 20503. If a (See NUREG-1022, R.3 for instruction and guidance for completing this form means used to impose an infoITTlation collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the infoITTlation collection.
: 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE Oyster Creek, Unit 1 05000 -0219 1 OF 4 4. TITLE Technical Specification Prohibited Condition Caused by One Electromatic Relief Valve Inoperable for Greater than Allowed Outage Time 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED YEAR I SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR NUMBER NO. MONTH DAY YEAR NIA N/A FACILITY NAME DOCKET NUMBER 09 19 2016 2016 -005 -01 09 22 2017 NIA N/A 9. OPERATING MODE 11. THIS REPORT IS SUBMITIED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) D 20.2201(b) D 20.2203(a)(3Hi>
0 50.73(a)(2)(ii)(A) 0 50.73(a)(2)(viii)(A)
N D 20.2201 (d) D 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(B) 0 50.73(a)(2)(viii)(B)
D 20.2203(a)(1)
D 20.2203(a)(4)
D so.13(a)(2)(iiil 0 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(i) 0 50.36(c)(1)(i)(A) 0 50.73(a)(2)(iv)(A) 0 50.73(a)(2)(x)
: 10. POWER LEVEL D 20.2203(a)(2)(ii) 0 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(v)(A)
D 13.11(a)(4)
D 20.2203(a)(2)(iii)
D so.36(c)(2) 0 50.73(a)(2)(v)(B)
D 13.11(a)(s)
D 20.2203(a)(2)(1v)
D so.4a(a)(3)(11) 0 50. 73(a)(2)(v)(C)
D 13.77(a)(1) 000 0 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A) 0 50.73(a)(2)(v)(D)
D 13.77(a)(2)(i) 0 20.2203(a)(2)(vi)
C8J 50.73(a)(2)(i)(B) 0 50.73(a)(2)(vii)
D 13.11(a)(2)(ii)
D so. 73(a)(2l(i)(C)
D OTHER Specify in Abstract below or in NRC Form 366A 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT rELEPHONE NUMBER (Include Area Code) Gary Flesher, Regulatory Assurance Manager (609) 971-4232
: 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CAUSE SYSTEM COMPONENT MANU* REPORTABLE CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX FACTURER TO EPIX 8 SB RV 0245 y NIA NIA NIA NIA NIA 14. SUPPLEMENTAL REPORT EXPECTED 15.EXPECTED MONTH DAY YEAR 0 YES (If yes. complete
: 15. EXPECTED SUBMISSION DATE) C8J NO SUBMISSION DATE NIA NIA NIA ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) On September 19, 2016, after achieving Cold Shutdown for the 1 R26 Refuel Outage, as found testing was performed on all five (5) Electromatic Relief Valves (EMRVs). The "E" EMRV did not open from the Main Control Room (MCR), and no change in indication was observed. Per the work activity, technicians were dispatched to the Drywell to verify that the valve did not move upon receiving an open signal from the MCA. A cutout switch in the valve actuator was stuck in the open position, thereby preventing a solenoid from actuating to open the valve. The cutout switch did not operate as required because the hinge pin lock star washers were not installed in the cutout switch assembly.
Without the lock star washers installed, the hinge pins interfered with the solenoid frame holes creating mechanical binding. Based on this information it is suspected that the "E" EMRV would have been inoperable for longer than the Technical Specification Allowed Out of Service Time (AOT) of 24 hours. Therefore, this issue is reportable under 1 O CFR 50. 73(a)(2)(i)(B) as an Operation or Condition which was Prohibited by the plant's Technical Specifications.
NRC FORM 366 (06-2016)
NRC FORM 366A (06-2016)) U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES:
10/31/2018 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/@
Estimated burden per response to comply with this mandatory coHection request:
BO hours. Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555*0001, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory
: Affairs, NEOB-10202, (3150-0104),
Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currenUy valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
: 1. FACILITY NAME 2. DOCKET NUMBER 3. LEA NUMBER Oyster Creek, Unit 1 NARRATIVE Plant Conditions Prior To Event Event Date: Unit 1 Mode: September 19, 2016 Cold Shutdown Description of Event 05000-0219 Event Time: Power Level: 1500 EDT 0% YEAR 2016 -SEQUENTIAL NUMBER 005 REV NO. -01 On September 19, 2016 after achieving Cold Shutdown for the 1 R26 Refuel Outage, as found testing was performed on all five (5) Electromatic Relief Valves (EMRVs).
The "E" EMRV did not open from the Main Control Room (MGR), and no change in indication was observed.
Per the work activity, technicians were dispatched to the Drywell to validate that the valve did not move upon receiving an open signal from the MGR. Troubleshooting was developed and determined that the cutout switch in the valve actuator was stuck in the open position, thereby preventing the actuator pickup solenoid from energizing to open the valve. The cutout switch did not operate as required because the hinge pin lock star washers were not installed in the cutout switch assembly.
Without the lock star washers installed, the hinge pins interfered with the solenoid frame holes creating mechanical binding.
During each refueling outage, all five (5) EMRV actuators are removed from the plant, refurbished, and reinstalled during the following refueling outage. By Oyster Creek Nuclear Generating Station (OCNGS) process, the EMRV actuators are refurbished with new springs, posts, guides, and microswitches every 24 months during refueling outages. The actuator inspection/refurbishment frequency of 24 months is more frequent than the manufacturer's (Dresser Industries) recommended frequency of 36 months (per Vendor Manual VM-OC-0030, Installation and Maintenance Manual for Electromatic Relief Valves, Revision 1, Section VII, Ref. 4.5). Equipment Description The EMRVs are Type 6" 1525-VX relief valves manufactured by Dresser Industries.
They are installed on the two (2) main steam lines that carry steam from the reactor vessel to the main turbine.
Actuation signals from either the Automatic Depressurization System or the individual EMRV pressure
: switches, as well as from the manual control switches will open the valves to lower reactor pressure, thereby allowing the low pressure Core Spray System to provide makeup water to the reactor core during accident I transient conditions.
The main valve is operated by a pilot valve that is controlled by energizing a DC operated solenoid actuator.
When energized, the solenoid develops an electromagnetic field that enables the downward travel of a plunger, which strikes the pilot valve lever pushing it down. In that position, the lever opens the exhausVventing path of the main valve, which subsequently opens the EMRV. The solenoid actuator is equipped with two solenoid coils (a pickup, low resistance
-50 coil, and a hold, high resistance
-3000 coil) in series. The hold coil has a parallel cutout switch, which is normally closed, thus bypassing the hold coil during the initial solenoid actuation.
The initial pickup current in that configuration
(-20 amps) is capable of developing the force required by the plunger for striking down the pilot valve lever and opening the EMRV. During its downward travel, the plunger tail will also strike down the cutout switch lever, which opens the cutout switch and connects the hold coil into the circuit.
The low current developed
(-0.5 Amps) in that configuration is required to allow the EMRV to remain open, as needed, without the risk of burning out the pickup coil. NAC FOAM 366A (06-2016)
Page _2_ of _4_
NRC FORM 366A (06-2016))
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/@
Estimated burden per response to comply with this mandatory collection request:
eo hours. Reported lessons learned are incorporated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch {T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001
, or by e-mail to lnfocollects.Resource@nrc
.gov, and to the Desk Officer, Office of Information and Regulatory
: Affairs, NEOB-10202, (3150-0104),
Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection
. 1. FACILITY NAME 2. DOCKET NUMBER 3. LEA NUMBER YEAR Oyster Creek, Unit 1 05000-0219 SEQUENTIAL NUMBER REV NO. 2016 -005 -01 NARRATIVE Analysis of Event When the EMRV is no longer required to be open, the solenoid coils are de-energized, and the plunger travels upward pulled by the actuator springs.
As it travels upward, the plunger releases the cutout switch lever, which retracts to its initial (closed) position helped by the combination of a tension and torsional springs.
The failure of the cutout switch to retract to its normal (closed) position would result in the pickup and hold coil simultaneously energized during an EMRV actuation, which would subsequently prevent the solenoid from developing the required force to overcome the actuator spring force, inhibiting the EMRV from opening.
Based on the failure mechanism, it has been determined that the "E" EMRV was inoperable for longer than the Technical Specification Allowed Out of Service time of 24 hours. There was no actual safety consequence associated with this event. The results of the analysis performed substantiate that the cause of the event was isolated to the "E" EMRV only. Cause of Event The "E" EMRV failure was caused due to the failure to install the hinge pin lock star washers in the cutout switch assembly.
Without the lock star washers installed, the hinge pins interfered with the solenoid frame holes creating binding and rotational forces that resulted in a deformation of the cutout switch lever arm. The lever arm deformation allowed the lever arm to bind on the solenoid frame and could not be overcome by the spring force. This condition resulted in the cutout switch being held open and the "E" EMRV unable to actuate.
Immediate Actions Extent of Condition Inspections were performed on the other four (4) EMRV actuators that were removed during 1 R26 Refuel Outage. Discrepancies were identified with the "E" EMRV only. Corrective Actions 1. Inspected all five (5) EMRV solenoid actuators prior to installation in the plant to verify critical parameters as wen as installation of the hinge pin lock star washers.
: 2. Implemented a policy improving field observations and increasing the criticality requirements.
: 3. Revised procedure to rebuild EMRVs to include verification signatures for critical steps. NRC FORM 366A (06-2016) Page _3_ of _4_
NRC FORM 366A (06-2016)) U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES:
10/31/2018 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www
.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/r31)
Estimated burden per response to comply with this mandatory collection request: 80 hours. Reported lessons learned are incorporated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the FO!A, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555*0001, or by e-mail to lnfocollects
.Resoun:e@nrc
.gov, and to the Desk Officer, Office of Information and Regulatory
: Affairs, NEOB-10202, (3150-0104),
Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
: 1. FACILITY NAME 2. DOCKET NUMBER 3. LEA NUMBER YEAR Oyster Creek, Unit 1 05000-0219 SEQUENTIAL NUMBER REV NO. 2016 -005 -01 NARRATIVE Assessment of Safety Consequences There was no actual safety consequences associated with this event. All EM RVs were operable at the time of installation during 1 R25 Refuel Outage (2014) as proven by operability surveillance testing during start-up from the outage. During Cycle 25, the OCNGS did not have any transients or events which required the "E" EMRV to operate.
Additionally, OCNGS UFSAR Chapter 15, assumes four out of the five EM RVs are available for any of the accident analyses requiring EMRV operation/actuation.
The Electromatic Relief Valves (EMRVs) have three modes of operation that were evaluated for Design Basis. These three modes are: 1) Automatic operation under Small Break Loss of Coolant Accident (SBLOCA) conditions
: 2) Automatic operation under high Reactor Pressure Vessel (RPV) Pressure condition
: 3) Manual operation under conditions dictated by the Emergency Operating Procedures (EOPs) The 'B', 'C', and 'E' EMRV have a setpoint to open at 1085 psig, which is higher than the setpoints for the 'A' and 'D' EMRV of 1065 psig. Time delay relays prevent the simultaneous opening of the EMRVs. The failure of the EMRV cutout switch lever arm would have precluded the "E" EMRV assembly from being able to cycle open in the event of an automatic or manual actuation.
The remaining four (4) of the five (5) EMRVs would have continued to operate and would have cycled as required to ensure operations under a SBLOCA or RPV high pressure condition.
The 'A' through 'D' EMRVs were evaluated to not be susceptible to a common cause failure and were maintained in an operable condition in accordance with station procedures.
Previous Occurrences In 2014 the station experienced an event in which two (2) actuators were found to be inoperable during the refurbishment
: process, after removal from the plant in September 2012 during the 1 R24 Refuel Outage. The station performed the corrective actions to change the design of the EMRV solenoid actuators to prevent recurrence.
The newly designed actuators were installed in September 2014 during OCNGS 1 R25 Refuel Outage. Additionally, a corrective action was implemented to perform as found testing during subsequent refuel outages prior to replacing the actuators.
The performance of these modifications was not a contributing cause to the failure experienced in the "E" EMRVon September 19, 2016. Component Data Component IEEE 805 System ID IEEE 803A Component Relief Valve SB RV NRC FORM 366A (06-2016)
Page _4_ of _4_}}

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