B16326, Provides Updated Response to GL 96-01, Testing of SR Logic Circuits

Provides Updated Response to GL 96-01, Testing of SR Logic Circuits

ML20137S694
Person / Time
Site:	Millstone
Issue date:	04/03/1997
From:	Brothers M NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES SERVICE CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
B16326, GL-96-01, GL-96-1, NUDOCS 9704150220
Download: ML20137S694 (4)

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\ Northead R pe Feny Rd. (Route 156h Tuedord,6385 Nuclear Energy Millstone Nuclear Power Station

' Northeast Nuclear Energy Company P.O. Box 128 Waterford, CT 06385-0128 (203) 447-1791 Fax (203) 444-42'/7 l ne Northeast Utdities System .

APR 3 B!TT Docket No. 50-423  !

B16326 l l

U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001

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Millstone Nuclear Power Station Unit No. 3 l Updated Response to Generic Letter 96-01 Testina of Safety-Related Loaic Circuits  ;

l NRC Generic Letter (GL) 96-01 " Testing of Safety Related Logic Circuits" requested that licensees submit a written response indicating whether or not the licensee would implement the actions related to the comparison of electrical schematic drawings and logic diagram against plant surveillance test procedures, to ensure that all portions of the logic circuitry are adequately covered in the surveillance procedures that fulfill the Technical Specification requirements. Additionally, the Generic Letter requested that surveillance procedures be modified as necessary to assure complete testing in l compliance with the Technical Specifications. These actions were required for the Reactor Protection System, Emergency Diesel Generator (EDG) Load Shedding and Sequencing, and the actuation logic for the Engineered Safety Features systems. In a letter dated April 16,1996, Northeast Nuclear Energy Company (NNECO) provided a response to GL 96-01. The purpose of this letter is to provide an update to that response.

In our previous correspondence, NNECO stated that in 1993 a Task Force had performed a review of the systems detailed above against the plant surveillance procedures. This review was performed to ensure that portions of the logic circuitry, including the parallel logic, interlocks, bypasses and inhibit circuits, were adequately covered in the surveillance procedures, and fulfilled the Technical Specification requirements. Additionally, the review included relay contacts, control switches, and b.Q(D5;I 9704150220 970403 D PDR ADOCK 05000423 p PDR oom4 uv. im $]%Ilhhhh,@

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U.S. Nuclear Regulitory Commission l B16326\Page 2 l other relevant electrical components within these systems, utilized in the logic circuits j performing a safety function.

) in April 1996, NNECO did not intend to perform additional reviews of these systems as i part of Generic Letter 96-01, except to review design modifications performed against l those systems since the conclusion of the Task Force. This review of the modifications

has been completed and no problems were identified with the surveillance test program for applicable circuits.

j However, a recent NRC review of the overlap test process identified some i discrepancies in the testing of the degraded voltage and undervoltage schemes.

l NNECO performed a self-assessment of the 1993 Task Force effort and identified an i additional problem with the testing of the Auxiliary Feedwater valves. The self-assessment concluded that the initial 1993 review did not have sufficient detail to meet the requirements of GL 96-01, and that the results were not adequately documented.

The degraded voltage and Auxiliary Feedwater valve testing discrepancies were  !

documented in Licensee Event Report (LER) 97 017-00. In the LER, NNECO committed to review the requirements of GL 96-01 in their entirety and include any reportable conditions in a supplement to the LER. This review will be completed prior to Mode 4 of the current outage, as stated in Attachment 1 of our LER submittal.

Should you have any questions regarding this submittal, please contact Mr. James M.

Peschel at (860) 437-5840 Very Truly yours, I

NORTHEAST NUCLEAR ENERGY COMPANY l h

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M. H. Brothers  !

Vice President - Millstone Unit No. 3 cc: H. J. Miller, Region i Adminis,trator W. D. Travers, PhD, Director, Special Projects Office J. W. Andersen, NRC Project Manager, Millstone Unit No. 3 A. C. Corne, Senior Resident inspector, Millstone Unit No. 3

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4 Docket No. 50-423 B16326 l

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l Attachment 1 1

Millstone Nuclear Power Station, Unit No. 3 NNECO's Commitments for the Updated Response to Generic Letter 96-01 Testing of Safety-Related Logic Circuits i 1

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1 April 1997 l

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U.S. Nuclear Regulatory Commission

, . B16326%ttachment 1\Page 1 4

t Enclosure List of Regulatory Commitments The following table identifies those actions committed to by NNECO in this document.  !

Any other actions discussed in the submittal represent intended or planned actions by

, NNEGO. They are described to the NRC for the NRC's information and are not regulatory commitments. Please notify the Manager - Nuclear Licensing at the Millstone Nuclear Power Station Unit No. 3 of any questions regarding this document or 4

any associated regulatory commitments.

i Number Commitment Due '

B16264-01 The requirements of Generic Letter 96-01 will Prior to entering be reviewed in their entirety. Any reportable Mode 4 ,

conditions discovered during this review will be reported in a supplement to LER 97-017-00.

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