05000353/LER-1917-007, Regarding Reactor Mode Switch Change During RCIC Testing
| ML17332A077 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 11/28/2017 |
| From: | Libra R Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LG-17-155 LER 17-007-00 | |
| Download: ML17332A077 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) |
| 3531917007R00 - NRC Website | |
text
Exelon Generation LG-17-155 November 28, 2017 U.S. Nuclear Regulatory Commission A TIN: Document Control Desk Washington, DC 20555-0001
Subject:
Limerick Generating Station, Unit 2 Renewed Facility Operating License No. NPF-85 NRC Docket No. 50-353 LER 2017-007-00, Reactor Mode Change During RCIC Testing &
Unit 2 LER Numbering 10 CFR 50.73 Enclosed is a Licensee Event Report (LER) which addresses a Mode Change with Reactor Core Isolation Cooling (RCIC) Testing in progress at Limerick Generating Station (LGS) Unit 2.
This LER is being submitted pursuant to the requirements of 1 O CFR 50. 73(a)(2)(i)(B),
Operation or Condition Prohibited by Technical Specifications.
Additionally, this letter is informing the NRC per NUREG-1022, Revision 3, that LER numbers 001, 002, and 003 for docket 05000353 will not be used.
There are no commitments contained in this letter.
If you have any questions, please contact Robert B. Dickinson at (610) 718-3400.
Respectfully,
~Richard W. Libra Vice President - Limerick Generating Station Exelon Generation Company, LLC cc: Administrator Region I, USNRC USNRC Senior Resident Inspector, LGS
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150*0104 EXPIRES: 03/31/2020 (04-2017)
, the http://www.nrc.qov/readinq-rm/doc-collections/nureqs/staff/sr1022/r3/)
NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Limerick Generating Station, Unit 2 05000353 1 OF 3
- 4. TITLE Reactor Mode Switch Change During RCIC Testing
- 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 FACILITY NAME DOCKET NUMBER 05 26 17 2017 - 007
- - 00 11 28 17
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITIED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
D 20.2201 (bl D 20.2203(aH3Hil D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A)
D 20.2201 (dl D 20.2203(aH3Hiil D 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B) 1 D 20.2203(a)(1 l D 20.2203(a)(4l D so.13(a)(2)(iiil D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(il 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 13.11 (aH4l D 20.2203(a)(2)(iiil D so.3s(c)(2J D 50.73(a)(2)(v)(B)
D 13.11 (a)(sJ D 20.2203(a)(2)(iv)
D so.4s(a)(3)(iil D 50.73(a)(2)(v)(C)
D 13.11(a)(1 l 008 D 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(D)
D 13.11(a)(2)(il D 20.2203(a)(2)(vi)
~ 50.73(a)(2)(i)(B)
D 50.73(a)(2)(vii)
D 73.11(a)(2)(iil D 50.73(a)(2)(i)(C)
D OTHER Specify in Abstract below or in SEQUENTIAL NUMBER 007 REV NO.
00 that this determination was not correct. Specifically, TS 3.0.4 states that when an LCO is not met, entry into an operational condition shall only be made in accordance with TS 3.0.4.a, 3.0.4.b, or 3.0.4.c. However, the conditions for TS 3.0.4.a, 3.0.4.b, and 3.0.4.c are not applicable to TS 3.7.3.
IV.
Safety Consequence
There was no actual safety consequence associated with this event. The RCIC system is a high-pressure coolant makeup system that is required for safe shutdown of the reactor whenever the reactor is isolated from its normal heat sink at elevated temperatures and pressures. TS Bases 3.7.3 identify that there is an increased risk associated with entering a mode with an inoperable RCIC subsystem. However, with the RCIC system inoperable, adequate core cooling is assured by the High Pressure Coolant Injection (HPCI) system, which was operable at the time, and therefore minimizes the safety significance of changing modes with RCIC inoperable.
V.
Cause of the Event
The cause of the event was the Control Room Supervisor (CRS) failed to maintain adequate control of plant evolutions prior to placing the Mode switch to RUN.
Per TS Surveillance 4.7.3.b, the RCIC surveillance test must be completed within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> of reaching adequate pressure. Based on past experiences, the Operations crew focused on ensuring the surveillance test was started as soon as possible after reaching adequate pressure to run the test.
Concurrently, the plan for completing the final steps of the Operations Procedure for "Limerick Start Up Review changed, causing a delay in changing OPCONs, as the RCIC test was initiated. The CRS did not adequately coordinate the two activities.
VI.
Corrective Actions Completed/Planned Performance management actions were applied for those personnel directly involved with the event.
Operations will revise the 'Normal Plant Startup' procedure to incorporate lessons learned from this event to ensure effective coordination during future plant startups.
A Corrective Action Program (CAP) assignment was created to develop a Shift Training Notification to be distributed to ensure gaps and lessons learned are shared with the Operations organization.
VII.
Previous Similar Occurrences There have been no previous similar occurrences of changing OPCONs with RCIC or any Emergency Core Cooling System (ECCS) equipment inoperable at LGS in the last 5 years. Page _3_ of _3_