ML20155C823

Forwards Safety Evaluation Accepting Withdrawal of ATWS Test Commitment

ML20155C823
Person / Time
Site:	Millstone
Issue date:	10/29/1998
From:	Mcdonald D NRC (Affiliation Not Assigned)
To:	Bowling M NORTHEAST NUCLEAR ENERGY CO.
Shared Package
ML20155C827	List: ML20155C823 ML20155C844
References
TAC-M99614, NUDOCS 9811030020
Download: ML20155C823 (2)

Text

_ _ - - _. .- -

Mr. M:rtin L. Bowling, Jr.

Rtcov:;ry Officer- Technical S rvic:s October 29, 1998

, North;ast Nucl;ar Ensrgy Comprny PUBLIC clo Ms. Patricia A. Loftus Director- Regulatory Affairs P. O. Box 128 Waterford, Connecticut 06385

SUBJECT:

ANTICIPATED TRANSIENT WITHOUT SCRAM COMMITMENT TEST WITHDRAWAL- MILLSTONE NUCLEAR POWER STATION, UNIT NO 2 (TAC NO. M99614)

Dear Mr. Bowling:

By letter dated September 5,1997, as supplemented on May 6 and September 14,1998, Northeast Nuclear Energy Company (NNECO) requested NRC staff approval to withdraw a commitment made on July 25,1988, as part of its anticipated transient without scram (ATWS) modifications for the Millstone Nuclear Power Plant, Unit 2. NNECO had committed to test one set of ac voltage output alarms, charger trouble alarms, and dc bus undervoltage alarms at attemate refueling outages.

The NRC staff has completed its review of NNECO's request and has determined that adequate justification has been provided to support the withdrawal of the ATWS test commitment. The staff has further determined that NNECO has provided adequate justification that the ATWS mitigating system and the reactor protection system will continue to perform their intended functions when subject to a failure of a common power supply and the bypass of Channel A high pressurizer pressure. The enclosed Safety Evaluation provides the details of the NRC staff's review.

This completes all NRC staff actions related to the referenced TAC number, if you have any questions, please call me at (301) 415-1408.

Sincerely, Oriignal signed by:

Daniel G. Mcdonald, Jr., Senior Project Manager 9811030020 981029 Millstone Project Directorate PDR ADOCK 05000336 Division of Reactor Projects - !/II P PDR Office of Nuclear Reactor Regulation Docket No. 50-336

Enclosure:

Safety Evaluation f cc w/ encl: See next page Q1SIRIBUTION:

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PUBLIC JZwolinski MSPD R/F JJoyce, HICB LBerry JWermiel, HICB WDean THarris (e-mail SE)

DMcDonald OGC gj ' ,3 DOCUMENT NAME: G:\ MCDONALD \M99614.SER To ree'ive a cop'r of this document, Indicate in the box: "C' = Copy withpyt attachmentlenclosure "E" = Copy with attachmentlenclosure "N* = No copy OFFICE MSPD:PMd3 MSPD:LA\ 'M NISPD:PN II) MSPD:D ,,()

NAME DMcDonaid d[h\) / LBerry M\ ' MDembe C WDean (Ml5/

DATE 104698 NJ' 10/ /98 '

10/T198 1QfQ/98 10/ /98 g( OFFICIAL RECORD COPY

A f:Ecp y t UNITED STATES j

g NUCLEAR REGULATORY COMMISSION a f WASHINGTON, D.c. 30666 4001 k . . . . . ,o# October 29, 1998 Mr. Martin L. Bowling, Jr.

Recovery Officer - Technical Services Northeast Nuclear Energy Company clo Ms. Patricia A. Loftus Director- Regulatory Affairs P. O. Box 128 Waterford, Connecticut 06385

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SUBJECT:

ANTICIPATED TRANSIENT WITHOUT SCRAM COMMITMENT TEST )

WITHDRAWAL - MILLSTONE NUCLEAR POWER STATION, UNIT NO. 2 l (TAC NO. M99614) )

1

Dear Mr. Bowling:

By letter dated September 5,1997, as supplemented on May 6 and September 14,1998, Northeast Nuclear Energy Company (NNECO) requested NRC staff approval to withdraw a commitment made on July 25,1988, as part of its anticipated transient without scram (ATWS) modifications for the Millstone Nuclear Power Plant, Unit 2. NNECO had committed to test one set of ac voltage output alarms, charger trouble alarms, and de bus undervoltage alarms at altemate refueling outages.

l The NRC staff has completed its review of NNECO's request and has determined that adequate justification has been provided to support the withdrawal of the ATWS test commitment. The staff has further determined that NNECO has provided adequate justification that the ATWS mitigating system and the reactor protection system will continue to perform their intended functions when subject to a failure of a common power supply and the bypass of Channel A high pressurizer pressure. The enclosed Safety Evaluation provides the details of the NRC staff's review.

This completes all NRC staff actions related to the referenced TAC number. If you have any questions, please call me at (301) 415-1408.

Sincerely,

- 'Q -

=

Daniel G. Mcdonald, Jr., Senior Project Manager Millstone Project Directorate Division of Reactor Projects - l/11 Office of Nuclear Reactor Regulation Docket No. 50-336

Enclosure:

Safety Evaluation cc w/enci: See next page