05000353/LER-2013-001, Regarding Valid Manual Actuation of the Reactor Protection System During Refuel Outage Testing
| ML13163A359 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 06/12/2013 |
| From: | Dougherty T Exelon Generation Co |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| LER 13-001-00 | |
| Download: ML13163A359 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 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)(iii) 10 CFR 50.73(a)(2)(ix)(A) 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)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3532013001R00 - NRC Website | |
text
10CFR50.73 June 12, 2013 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Limerick Generating Station, Unit 2 Facility Operating License No. NPF-85 NRC Docket No. 50-353
Subject:
LER 2013-001-00, Valid Manual Actuation of the Reactor Protection System This Licensee Event Report (LER) addresses a valid manual actuation of the reactor protection system (RPS) during an outage with all control rods inserted. The manual actuation of RPS was initiated when the mode switch was placed in the "Shutdown" position following an automatic actuation of RPS. The event was initiated by an unplanned automatic actuation of the turbine stop valve closed trip logic during an RPS surveillance test.
This LER is being submitted pursuant to the requirements of 10CFR50.73(a)(2)(iv)(A).
There are no commitments contained in this letter.
If you have any questions, please contact Robert B. Dickinson at (610) 718-3400.
Respectfully, Original signed by David P. Lewis for Thomas J Dougherty Thomas J. Dougherty 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 (10-2010)
LICENSEE EVENT REPORT (LER)
(See reverse for required number of digits/characters for each block)
APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY NAME Limerick Generating Station, Unit 2
- 2. DOCKET NUMBER 05000353
- 3. PAGE 1 OF 3
- 4. TITLE Valid Manual Actuation of the Reactor Protection System During Refuel Outage Testing
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL NUMBER REV NO.
MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 05000 04 16 2013 2013 - 001 -
00 06 12 2013 FACILITY NAME DOCKET NUMBER 05000
- 9. OPERATING MODE 4
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(i)(C) 50.73(a)(2)(vii) 20.2201(d) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2203(a)(1) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A) 20.2203(a)(2)(ii) 50.36(c)(1)(ii)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x) 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 50.73(a)(2)(v)(B) 73.71(a)(5) 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(C)
OTHER 20.2203(a)(2)(vi) 50.73(a)(2)(i)(B) 50.73(a)(2)(v)(D)
Specify in Abstract below or in LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET reactor was in cold shutdown with all control rods inserted at the time of the event.
The "Main Turbine CIV, Stop Valve RPS & EOC-RPT Channel Functional Test verifies the operability of the main turbine stop valve closed RPS logic. This trip function is bypassed when reactor power is less than 26 percent since the main steam bypass valves capacity is greater than 26 percent power. The test directs simulating greater than 26 percent power conditions if as-found power is less than 26 percent. The test section directs simulation of greater than 26 percent power at the main turbine first stage pressure trip units to defeat the bypass of the stop valves closed trip function.
The main turbine control valve test (ST-6-001-766-2) was scheduled following the stop valve test. The control valve test also required simulation of greater than 26 percent power at the first stage trip units. The operators decided to maintain simulated power conditions during the return to normal section of the stop valve test and the initial conditions section of the control valve test. This plan to alter the procedure sequence was not properly performed or technically reviewed per HU-AA-104-101 or HU-AA-1212.
Cause of the Event
The event was caused by a failure to follow the existing procedure change processes.
Corrective Action Completed A corrective action was completed which performed the following:
- 1) Reinforced the requirements for partial procedure use and temporary procedure changes,
- 2) Established expectations for the review and approval of partial procedures and temporary procedure changes, and
- 3) Established expectations for use and performance of technical human performance briefs (HU-AA-1212).
Previous Similar Occurrences There were no similar occurrences of valid manual actuation of the reactor protection system due to surveillance test status control errors in the previous three years.