LG-14-031, Special Report - Seismic Monitoring Instrumentation Inoperability Channel XE-VA- 102

Special Report - Seismic Monitoring Instrumentation Inoperability Channel XE-VA- 102

ML14069A171
Person / Time
Site:	Limerick
Issue date:	02/26/2014
From:	Dougherty T Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LG-14-031
Download: ML14069A171 (3)

Text

Exeton Generation, TRM 3.3.7.2 LG-14-031 February 26, 2014 U.S. Nuclear Regulatory Commission Attn.: Document Control Desk Washington, DC 20555-0001 Limerick Generating Station, Units 1 and 2 Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353

Subject:

Special Report - Seismic Monitoring Instrumentation Inoperability Channel XE-VA-102

References:

1. Special Report-Seismic Monitoring Instrumentation Inoperability, dated 01/16/13 This Special Report is being submitted pursuant to the requirements of Limerick Generating Station (LGS), Unit 1 and Unit 2 Updated Final Safety Analysis Report (UFSAR) section 3.7.4.5, Technical Specification 6.9.2, and Technical Requirements Manual 3.3.7.2 which states '"With one or more of the seismic monitoring instruments inoperable for more than 30 days, a Special Report shall be prepared and submitted to the Nuclear Regulatory Commission pursuant to Specification 6.9.2 of the Technical Specifications within the next ten days outlining the cause of the malfunction and the plans for restoring the instrument(s) to operable status."

On Friday January 17, 2014 Unit 1 and 2 were operating at 100% power with functional testing (ST-2-036-426-0) of the seismic monitoring instrumentation in progress. During the test, the seismic monitor sensor array (XE-VA-1 02) for the Primary Containment Foundation Sensor did not provide the Main Control Room (MCR) alarm or the local indicating light.

The XE-VA-102 array has three channels which measure longitudinal movement, vertical movement, and transverse movement. The transverse channel of XE-VA-1 02 will trigger XR-VA-102/103 to log/record data, but will not actuate the MCR alarm or the light as expected.

Accordingly, Operations declared the recorder inoperable. The other two XE-VA-1 02 channels for the horizontal and vertical directions function and will trigger, log/record data and provide the MCR alarm and the local indicating light.

Initial troubleshooting has not determined the cause. Additional troubleshooting will be required to identify the cause of the inoperable sensor XE-VA-1 02 and recorder XR-VA-102/103 for XE-VA-1 02. The sensor and recorder will be repaired, tested, and returned to operable status by the end of 1 R15 refueling outage (April 2014).

If you have any questions or require additional information, please do not hesitate to contact us.

Sincwerelly,..

Thomas J. Dougherty Vice President - Limerick Generating Station Exelon Generation Company, LLC

Attachment:

List of commitments cc: Administrator, Region I, NRC NRC Senior Resident Inspector, Limerick

SUMMARY

OF REGULATORY COMMITMENTS The following table identifies commitments made in this document. (Any other actions discussed In the submittal represent intended or planned actions. They are described to the NRC for the NRC's information and are not regulatory commitments.)

COMMITTED COMMITMENT TYPE COMMITMENT DATE OR "OUTAGE ONE-TIME PROGRAMMATIC ACTION (Yes/No)

(Yes/No)

The inoperable seismic monitor sensor array (XE-VA-Outage Yes No 102) that is located in the Unit 1 HPCI Room will be repaired, tested, and returned to operable status by the end of the 1 R15 refueling outage (April 2014).

The inoperable seismic monitor recorder XR-VA-Outage Yes No 102/103 for XE-VE-1 02 will be repaired, tested, and returned to operable status by the end of the 1 R15 refueling outage (April 2014).