05000348/LER-2012-003, Regarding Unplanned a Train LOSP During SI with LOSP Testing

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Regarding Unplanned a Train LOSP During SI with LOSP Testing
ML12152A374
Person / Time
Site: Farley Southern Nuclear icon.png
Issue date: 05/31/2012
From: Lynch T
Southern Nuclear Operating Co, Southern Co
To:
Office of Nuclear Reactor Regulation, Document Control Desk
References
NL-12-0771 LER 12-003-00
Download: ML12152A374 (7)
v • d • e


LER-2012-003, Regarding Unplanned a Train LOSP During SI with LOSP Testing
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)
10 CFR 50.73(a)(2)(viii)(A)
10 CFR 50.73(a)(2)(ii)(8)
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)(8)
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)(8)
3482012003R00 - NRC Website
v • d • e

text

Thomas A. Lynch Southern Nuclear Vice President* Farley Operating Company, Inc.

Farley Nuclear Plant Post Office Drawer 470 Ashford, Alabama 36312 Tel 334.814.4511 Fax 334.814.4728 SOUIHERN'\\'

COMPANY May 31. 2012 Docket No.:

50-348 NL on1 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Joseph M. Farley Nuclear Plant - Unit 1 Licensee Event Report 2012-003-00 Unplanned A Train LOSP during SI with LOSP Testing Ladies and Gentlemen:

In accordance with the requirements of 10 CFR 50.73 (a)(2)(iv)(A), Southern Nuclear Operating Company (SNC) is submitting the enclosed Licensee Event Report. This letter contains no NRC commitments. If you have any questions, please contact Doug McKinney at (205) 992-5982.

Sincerely, 1y T. A. Lynch Vice President - Farley TAlJWDO Enclosure: Unit 1 Licensee Event Report 2012-003-00

U. S. Nuclear Regulatory Commission NL 0771 Page 2 cc: Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bost, Executive Vice President &Chief Nuclear Officer Mr. B. L. Ivey, Vice President - Regulatory Affairs Mr. B. J. Adams, Vice President - Fleet Operations Mr. M. J. Ajluni. Director - Nuclear Licensing RTYPE: CFA04.054 U. S. Nuclear Regulatory Commission Mr. V. M. McCree, Regional Administrator Mr. R. E. Martin, NRR Project Manager - Farley Mr. E. L. Crowe, Senior Resident Inspector - Farley

Joseph M. Farley Nuclear Plant - Unit 1 Licensee Event Report 2012-003-00 Unplanned A Train LOSP during 51 with LOSP Testing Enclosure Unit 1 Licensee Event Report 2012-003-00

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/3112013 11).2010)

, the NRC may nol conduct or sponser. and a persen is not reqUired to respond to. the information collection.

1. FACILITY NAME
2. DOCKET NUMBEA
13. PAGE Joseph M. Farley Nuclear Plant, Unit 1 05000348 1 OF 4
14. TITLE Unplanned A Train LOSP during SI with LOSP 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 FACILIlY NAME DOCKET NUMBER FACILITY NAME DOCKET NUMBER 04 05 2012 2012

~ 003

  • 00 05 31 2012
9. OPERATING MODE
11. THIS REPORT IS SUBMllTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check a/l that apply) o 20.2201(b) o 20.2203(a)(3)(i) o 50.73(a)(2)(i)(C) o 50.73(a)(2)(vli) 6 o 20.2201 (d) o 20.2203(a)(3)(ii) o 50.73(a)(2)(i1)(A) o 50.73(a)(2)(viii)(A) o 2O.2203(a)(1) o 20.2203(a)(4) o 50.73(a)(2)(ii)(8) o 50.73(a)(2)(viii)(B) o 20.2203(a)(2)(i) o 50.36(c)(1)(i)(A) o 50.73(a)(2)(iii) o 50.73(a)(2)(ix)(A)
10. POWER LEVEL o 20.2203(a)(2)(ii) o 50.36(c)(1 )(ii)(A)

IE:! 50.73(a)(2)(iv)(A) o 50.73(a)(2)(x) o 20.2203(a)(2)(iii) o 50.36(c)(2) o 50.73(a)(2)(v)(A) o 73.71(a)(4) o 20.2203(a)(2)(iv) o 50.46(a)(3)(ii) o 50.73(a)(2)(v)(8) o 73.71(a)(5) 000 o 20.2203(a)(2)(v) o 50.73(a)(2)(i)(A) o 50.73(a)(2)(v)(C) o OTHER o 20.2203(a)(2)(vi) o 50.73(a)(2)(i)(8) o 50.73(a)(2)(v)(O)

Specify in Abslracl bEllow or In NRC Form 36GA

12. LICENSEE CONTACT FOR THIS LER FACILITY NAME ITELEPI-IONE NUMBER (Indude Area Code)

J.M. Farley Nuclear Plant, W. D. Oldfield - Principal licenSing Engineer (334) 814-4765 MANU*

REPORTABLE MANU-REPORTABLE

CAUSE

SYSTEM ICOMPONENT

CAUSE

SYSTEM 'COMPONENT FACTURER TO EPIX FACTURER TO EPIX r-------...-.-.--

I

14. SUPPLEMENTAL REPORT EXPECTED
15. EXPECTED MONTH DAY YEAR SUBMISSION o YES (If yes, complete 15. EXPECTED SUBMISSION DATE)

IE:! NO DATE

~8STRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)

On AprilS, 2012 at approximately 12:24, with Unit 1 in mode 6, an unplanned loss of power on A-train 4160 volt emergency bus 1 F occurred during a scheduled outage test. Safety Injection (SI) with Loss of Off-Site Power (LOSP). Prior to the event, the 1-2A Emergency Diesel Generator (EDG) was solely aligned to the 1 F bus and successfully carrying all the loads per the test sequence. During subsequent restoration steps the 1-2A EDG should have been paralleled to the grid, however, a human performance error was made and this procedure step was not correctly performed. When the B1 F Sequencer Test Trip Override Switch (TIOS) was selected to the 'On' position, the EDG output breaker (DF08-1) opened to generate an LOSP signal on the 1F bus. As a result, the B1F Sequencer functioned to automatically re-close DF08-1, and automatically start all LOSP loads. All systems functioned as designed for this condition. Since core cooling was aligned to the A-train prior to the event, the A-train 1A Residual Heat Removal (RHR) pump was deenergized when the LOSP occurred.

This pump is not an LOSP load and therefore did not automatically restart. The 1A RHR pump was manually restarted one minute after the LOSP to reestablish core COOling after an increase in reactor coolant system (RCS) temperature of approximately four degrees. Unit 2 was unaffected and remained at 100 percent power during the event.

Once the error was recognized, the surveillance test procedure was properly executed to restore off-site power and shutdown the 1-2A EDG without further complications.

NRC fORM 366 (1()'2010)

Safety Assessment

This event had no adverse effect on the safety and health of the public. There were no safety system functional failures and all systems functioned as designed.

The Farley onsite standby power source is provided from four EDGs (1-2A, 1 B, 2B, and 1 C). EDGs 1 2A and 1 C are A-Train and EDGs 1 Band 2B are B-Train. Farley also has a fifth diesel generator (2C) that serves as a station blackout diesel, which can be manually aligned to supply B-Train power to either unit and power LOSP loads.

During the restoration portion of the test procedure, EDG 1-2A was operating and tied to the 1 F Emergency Bus. During subsequent restoration steps the 1-2A EDG should have been paralleled to the grid, however, a human performance error was made and this procedure step was not correctly performed. When the B1 F Sequencer Test Trip Override Switch (TIOS) was selected to the 'On' position, the EDG output breaker (DF08-1) opened to generate an LOSP signal on the 1 F bus.

Sensing the LOSP condition, the B1 F Sequencer properly functioned to re-close DF08-1 and sequentially start and connect loads on emergency Bus 1 F. Loads are automatically and sequentially started per design to prevent overloading of the EDG. The EDG output breaker closure and sequencing of shutdown loads are required functions of an EDG and therefore had no adverse effect on the safety and health of the public.

The A-train 1 A RHR pump was deenergized when the LOSP occurred. This pump is not an LOSP load and therefore did not automatically restart since a safety injection (SI) Signal was not present. The 1 A RHR pump was manually restarted one minute after the LOSP to reestablish core cooling after a slight increase in reactor coolant system (RCS) temperature of approximately four degrees. The B-train 1 B EDG was operable and the B-train 1 B RHR pump was available to be started if needed. Since both AHR trains were available and the 1A RHR pump was restarted, a loss of safety function did not occur.

This event is reportable pursuant to 10 CFR 50.73 (a)(2)(iv)(A) for a system actuation.

Corrective Action

Once the error was recognized, the surveillance test guidance was properly executed to restore off-site power, shutdown the 1-2A EDG, and successfully complete the SI with LOSP test procedure.

Causal analysis was completed and additional actions to enhance the procedure and improve the identification of critical steps were identified; and will be tracked to closure in the corrective action program (CAP).

Industry Operating Experience (OE) on the event has been issued.

NRC FOf'lM 36BA (10*201 0) LICENSEE EVENT REPORT (LER) u.s. NUCLEAR REGULATORY COMMISSION (1 ()'2010)

CONTINUATION SHEET I

1. FACILITY NAME
2. DOCKET
6. LER NUMBER
3. PAGE SEOUENTIAL IREVISION YEAR NUMBER NUMBER I--_~-...i-.._____..

Joseph M. Farley Nuclear Plant, Unit 1 05000 348 4

of 4

2012 003 00 NARRATlVE

Additional Information

Similar Events:

LEA 2010-001-00 Unit 2 - Unplanned LOSP during SI with LOSP Testing LEA 2009-001-00 Unit 1 and 2 - EDG 1 C Auto Start due to Inadvertent Relay Actuation NRC FORM 36BA (10-2010)

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