05000373/LER-1917-007, Regarding Low Pressure Core Spray System Inoperable Due to Loss of Cooling
| ML17230A288 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 08/18/2017 |
| From: | Vinyard H Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RA17-076 LER 17-007-00 | |
| Download: ML17230A288 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) |
| 3731917007R00 - NRC Website | |
text
Exelon Generation..
RA17-076 August 18, 2017 u_s. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 LaSalle County Station, Unit 1 Renewed Facility Operating License No. NPF-11 NRC Docket No. 50-373 LaSalle County Station 2601 North 21*1 Road Marseilles, IL 61341 815-415-2000 Telephone www.exeloncorp.com 10 CFR 50.73
Subject:
Licensee Event Report 2017-007-00, Low Pressure Core Spray System Inoperable due to Loss of Cooling In accordance with 1 O CFR 50.73(a)(2)(v)(D), Exelon Generation Company, LLC (EGC) is submitting Licensee Event Report (LEA) Number 2017-007-00 for LaSalle County Station, Unit 1.
There are no regulatory commitments in this letter. Should you have any questions concerning this report, please contact Mr. Guy V. Ford, Jr., Regulatory Assurance Manager, at (815) 415-2800.
Harold T. Vinyar Plant Manager LaSalle County Station
Enclosure:
Licensee Event Report cc:
Regional Administrator - NRC Region Ill NRC Senior Resident Inspector - LaSalle County Station
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150*0104 EXPIRES: 03/31/2020 (04-2017)
Esbmated, the bJtp://www.nrc.gov/reading-rm/doc-collections/nure_gs/staff/sr1022/r3/)
NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE LaSalle County Station, Unit 1 05000373 1 OF 3
- 4. TITLE Low Pressure Core Spray System Inoperable due to Loss of Cooling
- 5. EVENT DATE
- 6. LEA NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED I
SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR NUMBER NO.
MONTH DAY YEAR NA NA FACILITY NAME DOCKET NUMBER 06 22 2017 2017 - 007 00 08 18 2017 NA NA
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
D 20.2201 (bl D 20.2203(a)(3Hil D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A)
D 20.2201 (dl D 20.2203(a)(3)(iil D 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B) 1 D
D D 5o.73(a)(2)(1iil D 50.73(a)(2)(ix)(A) 20.2203(a)(1) 20.2203(a)(4)
D 20.2203(a)(2)(i)
D 50.36(c)(1 )(i)(A)
D 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x)
- 10. POWER LEVEL D 20.2203(a)(2)(iil D 50.36(c)(1 )(ii)(A)
D 50.73(a)(2)(v)(A)
D 73.71 (a)(4)
D 20.2203(a)(2)(iiil D so.3s(c)(2)
D 50.73(a)(2)(v)(B)
D 73.71 (a)(S)
D 20.2203(a)(2)(iv)
D 5o.4s(a)(3)(iil D 50.73(a)(2)(v)(C)
D 13.11(a)(1) 100 D 20.2203(a)(2)(v)
D 50. 73(a)(2)(i)(A)
~ 50. 73(a)(2)(v)(D)
D 1a.n(a)(2)(il D 20.2203(a)(2)(vi)
D 50.73(a)(2)(i)(B)
D 50. 73(a)(2)(vii)
D 1a.n(a)(2)(ii)
D 50.73(a)(2)(i)(C)
D OTHER Specify in Abslracl below or in REPORT ABILITY AND SAFETY ANALYSIS SEQUENTIAL NUMBER 007 REV NO.
00 The required action of Technical Specifications (TS) 3.5.1, "EGGS - Operating" was entered on June 22, 2017 at 2043 CDT when the condition was identified, and the LPCS system was determined to be inoperable. The TS limiting condition of operation (LCO) was exited on June 23, 2017 at 1357 CDT when the station transitioned Unit 1 to Mode 4 in support of the planned maintenance outage L 1 M22. Troubleshooting, associated component maintenance, and system testing was completed on June 24, 2017 at 1518 CDT.
This component inoperability is reportable in accordance with 10 CFR 50. 73(a)(2)(v)(D) as an event or condition that could have prevented fulfillment of the safety function of structures or system that are needed to mitigate the consequences of an accident.
This condition could have prevented the LPCS system, a single train safety system, from performing its design function. There was minimal safety consequences associated with the condition since other required emergency safety systems remained operable, there were no actual demands for Unit 1 LPCS, and safety margins were maintained.
This condition was determined to be a safety system functional failure (SSFF) as defined in accordance with NEI 99-02, Regulatory Assessment Performance Indicator Guideline.
CORRECTIVE ACTIONS
Corrective actions were taken to replace the OHS-DG001 A control switch and the 1 VY01 C control relay during troubleshooting.
PREVIOUS OCCURRENCES
A review of station Licensee Event Reports and corrective action program (CAP) data for the past three years, related to switch failures, identified the following similar instance:
ICES 322935 - LaSalle Unit 1, Reactor Building Ventilation Fan Tripped During Fan Swap (April 29, 2016)
Operations personnel were performing a fan swap on Reactor Building Ventilation (VA), when the fan tripped shortly after starting.
The consequence was loss of one ventilation fan; however, there are three fans in the train where only two fans are needed for normal operation. The failure was due to switch stop contacts stuck closed in the Control Room. The cause was SBM-style switch stop contacts stuck closed giving a stop signal when the switch was taken to start. The switch was replaced with a new one and tested successfully. Actions to prevent recurrence were determined to be not needed because the switch has been reliable and there has not been a failure of the SBM switch component in over fifteen years on any of the twelve VA supply/exhaust fans, and the device's preventative maintenance was in alignment with station expectations.
COMPONENT FAILURE DATA
Manufacturer: General Electrical Company (G080)
Device: Diesel Generator O Cooling Water Pump Hand/Control Switch Component ID: OHS-DG001A, Model: Q16SBMD4C42P1F1P1 (SBM)
NAC FOAM 366A (04-2017)
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