ML092590055

Special Report for Seismic Instrumentation

ML092590055
Person / Time
Site:	Millstone
Issue date:	09/08/2009
From:	Jordan A Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
09-577, FOIA/PA-2011-0115
Download: ML092590055 (3)

Text

Dominion Nuclear Connecticut, Inc.

Millstone Power Station Dominion-Rope Ferry Road Waterford, CT 06385 SEP 0 8 2009 U.S. Nuclear Regulatory Commission Serial No.09-577 Attention: Document Control Desk NSSL/RWM RO Washington, DC 20555 Docket No. 50-336 License No. DPR-65 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2 SPECIAL REPORT FOR SEISMIC INSTRUMENTATION Dominion Nuclear Connecticut, Inc. (DNC) hereby for'Wards a special report in accordance with the Millstone Power Station Unit 2 (MPS2) Technical Requirements Manual (TRM) 3.3.3.3, Seismic Instrumentation.

MPS2 TRM 3.3.3.3.b requires a special report be submitted to the Nuclear Regulatory Commission (NRC) within 10 days when one or more seismic monitoring channels are inoperable for more than 30 days. The report for this condition is contained in .

If you have any questions regarding this submittal, please contact Mr. William D. Bartron at (860) 444-4301.

Sincerely, A. J. Jo ,dn Site Vice President - Millstone

Attachment:

1. Special Report for Seismic Instrumentation Commitments made in this letter: None cc: U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1415 Ms. C. J. Sanders Project Manager - Millstone Power Station U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop O-8B3 Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station

Serial No.09-577 Docket No. 50-336 ATTACHMENT I SPECIAL REPORT FOR SEISMIC INSTRUMENTATION DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

Serial No.09-577 Special Report for Seismic Instrumentation Docket No. 50-336 Attachment 1 Page 1 of 1 SPECIAL REPORT FOR SEISMIC INSTRUMENTATION This special report is being submitted pursuant to Millstone Power Station Unit 2 (MPS2)

Technical Requirements Manual (TRM) 3.3.3.3, "Seismic Instrumentation." The MPS2 TRM 3.3.3.3.b requires that a special report be submitted within 10 days when one or more seismic monitoring channels are inoperable for more than 30 days. This report describes the cause of the malfunction and the plans for restoring the system.

Seismic instrumentation ensures that sufficient capability is available to promptly determine the magnitude of a seismic event and evaluate the response of those features important to safety.

This capability is required to permit comparison of the measured response to that used in the design of the facility. Each required seismic monitoring instrumentation channel is demonstrated to be operable by the performance of channel check, channel calibration and channel functional test operations.

On July 28, 2009, during inspection and calibration of the seismic monitoring system instruments, MPS2 determined that one of five required seismic monitoring channels was not operable due to a faulty accelerometer assembly. A replacement accelerometer package is required and must be procured and installed to enable the seismic monitoring system channel calibration to be performed. The instrument is scheduled to be restored on September 18, 2009.