ML20217M418

Suppl Safety Evaluation Accepting Licensee RCS Pressure & Heat Removal by Containment Heat Removal Sys post-accident Monitoring Instrumentation

ML20217M418
Person / Time
Site:	Millstone
Issue date:	04/30/1998
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20217M416	List: ML20217M412 ML20217M418
References
NUDOCS 9805050002
Download: ML20217M418 (4)

Text

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' NUCLEAR REGULATORY COMMISSION

- WASHINGTON, D.C. 30006-0001

.,g* SUPPLEMENTAL SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION NORTHEAST NUCLEAR ENERGY COMPANY MILLSTONE NUCLEAR POWER STATION. UNIT NOL 2.

DOCKET NO. 50-336 CONFORMANCE TO REGULATORY GUIDE 1.97

1.0 INTRODUCTION

On November 22,1989, the NRC staff issued a Safety Evaluation Report regarding Northeast i

Nuclear Energy Company's (NNECO's or licensee's) conformance to Regulatory Guide

~(RG) 1.97, " Instrumentation for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident," Rsvision 2, for the Millstone Nuclear '

Power Station,' Unit No. 2. On February 5,1991, the staff issued a Supplemental Safety Evaluation Report (SSER) on the same subject whereby the NRC staff accepted certain licensee

. deviations from the RG 1.97 recommendations.

In submittals dated January 29,1998, and March 4,1998, the licensee requasted additional deviations from the RG 1.97 recommendations for the int,trumentation that monitors the reactor coolant system (RCS) pressure and heat removal by the containment heat removal system.

2.0 EVALUATION RG 1.97 recommends Category 1 RCS pressure instrumentation with a range of zero to 4000 pounds per square inch gauge (psig) for Combustion Engineering units such as the Millstone Nuclear Power Station, Unit No. 2. The licensee supplied redundant, Category 1 channels, from zero to 1600 psig and from 1500 to 2500 psig channels, and a single Category 3 channel from zero to 3000 psig. The NRC staff's February 5,1991, SSER accepted this instrumentation .

based on the assumption that the provided instrumentatian was adequate to monitor all expected pressures. based on the licensee's design basis event analysis and a commitment to upgrade the

' range of these instrumentation channels following the resolution of the anticipated transient

'without scram (ATWS) issue. In its January 29,1998, letter, the licensee stated that the existing instrumentation provides adequate indication to monitor an ATWS pressure transient. Therefore, the licensee has met its commitment and the existing RCS pressure instrumentation is acceptable.

~l Further, RG 1.97 recommends plant-specific Category 2 instrumentation to monitor heat removal i by the containment fan heat removal system.- The licensee's instrumentation to monitor the heat l

- removal consists of the reactor building closed cooling water (RBCCW) heat exchanger l discharge temperature, containment air recirculation and cooling system (CARCS) fan cooler discharge temperature, CARCS fan cooler discharge flow, and containment pressure.

The range of the CARCS fan cooler discharge temperature instrumentation is zero to 200'F. A l design review of the RBCCW system has identified increased CARCS fan cooler discharge i ADOC P. PM (

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temperatures up to 234*F for the first 22 minutes of the post-loss-of-coolant accident (LOCA) 4 injection phase of an accident. This off scale condition would not degrade the performance of the instrumentation and the temperature would be read after the first 22 minutes when it returns i below 200'F.

The CARCS fan cooler inlet temperature monitored by the RBCCW heat exchanger discharge temperature instrumentation, is calculated to be no greater than 147 F and will remain on scale

. during the time the CARCS fan cooler discharge temperature is off scale during the initial portion of the post-LOCA injection phase of an accident. Therefore, CARCS operation can be verified by monitoring CARCS fan cooler inlet temperature and CARCS discharge flow. The short time the CARCS fan cooler discharge temperature is off scale is acceptable because the instrumentation will function properly after the temperature returns to the indicated range and CARCS operation can be determined by other instrumentation.

3.0 CONCLUSION

' The NRC staff has determined, based on the preceding discussion, that the licensee has provided adequate justification for deviations from the RG 1.97, Revision 2, recommendations for the. instrumentation that monitors RCS pressure and heat removal by the containment heat removal system at the Millstone Nuclear Power Station, Unit No. 2. Therefore, the NRC staff concludes that the licensee's RCS pressure and heat removal by the containment heat removal system post-accident monitoring instrumentation are acceptable.

Principal Contributor Barry S. Marcus Date: April 30, 1998 i

Northscst Nucle:r Enirgy Company Millstone Nucl3rr Powsr St tion Unit 2 e

cc:

Lillian_M. Cuoco, Esquire - Mr. F. C. Rothen Senior Nuclear Counsel Vice President - Work Services Northeast Utilities Service Company Northeast Utilities Service Company P. O. Box 270 P. O. Box 128 Hartford, CT 06141-0270 ~ Waterford, CT 06385 Mr. John Buckingham .. Emest C. Hadley, Esquire Department of Public Utility Control .1040 B Main Street Electric Unit P.O. Box 549 -

10 Liberty Square West Wareham, MA 02576 New Britain, CT 06051 Mr. D. M. Goebel-Mr. Kevin T. A. McCarthy, Director Vice President - Nuclear Oversight Monitoring and Radiation Division . Northeast Utilities Service Company Department of Environmental Protection P. O. Box 128 79 Elm Street Waterford, CT 06385 Hartford, CT 06106-5127 Mr. David Amerine

- Regional Administrator, Region i .Vice President - Nuclear Engineering U.S. Nuclear Regulatory Commission and Support 475 Allendale Road Northeast Utilities Service Company King of Prussia, PA 19406 P. O. Box 128 Waterford, CT 06385 First Selectmen Town of Waterford Mr. Allan Johanson, Assistant Director Hall of Records Office of Policy and Management 200 Boston Post Road Policy Development and Planning Waterford, CT 06385 Division 450 Capitol Avenue - MS# 52ERN Mr. Wayne D. Lanning P. O. Box 341441 Deputy Director of Inspections Hartford, CT 06134-1441 Special Projects Office 475 Allendale Roari Mr. M. H. Brothers

. King of Prussia, PA ~ 19406-1415 -

Vice President - Operations Northeast Nuclear Energy Company Charles Brinkman, Manager P.O. Box 128 -

Washington Nuclear Operations Waterford, CT 06385 ABB Combustion Engineering 12300 Twinbrcok Pkwy, Suite 330 Mr. J. A. Price Rockville, MD 20852 Unit Director - Millstone Unit 2 Northeast Nuclear Energy Company

_ Senior Resident inspector P.O. Box 128 Millstone Nuclear Power Station Waterford, CT 06385 c/o U.S. Nuclear Regulatory Commission P.O. Box 513 Niantic, CT 06357

NorthEcst Nucl:cr EnIrgy Company Millstons Nuclear Powsr Station l'

Unit 2 i

cc:

Mr. B.- D. Kenyon Attomey Nicholas J. Scobbo, Jr.

Chief Nucler Officer- Millstone Ferriter, Scobbo, Caruso, Rodophele, PC Northeast Nuclear Energy Company 1 Beacon Street,11th Floor P.O. Box 128 Boston, MA 02108 Waterford, CT 06385 Citizens Regulatory Commission ATTN: Ms. Susan Perry Luxton 180 Great Neck Road I Waterford, CT 06385 Deborah Katz, President Citizens Awareness Network P. O. Box 83 Shelbume Falls, MA 03170 The Honorable Teny Concannon Co-Chair Nuclear Er my Advisory Council Room 4n" 5 Legislative 25ce Building Capitol Avenue Hartford, CT 06106 Mr. Evan W. Woollacott Co-Chair Nuclear Energy Advisory Council 128 Terry's Plain Road Simsbury, CT 06070 Little Harbor Consultants, Inc. '

Millstone - ITPOP Proj(ct Office P. O. Box 0630 Niantic, CT 06357-0630 Mr. Daniel L. Curry Project Director Parsons Power Group inc.

2675 Morgantown Road Reading, PA 19607

' Mr. Don Schopfer Verification Team Manager Sargent & Lundy l 55 E. Monroe Street

( ' Chicago, IL 60603 l