ML20151X343

SER Accepting Basis & Findings That Util post-accident Monitoring Instrumentation Meets Guidelines of Reg Guide 1.97 Except for Variable Neutron Flux Instrumentation

ML20151X343
Person / Time
Site:	Quad Cities
Issue date:	08/16/1988
From:	NRC
To:
Shared Package
ML20151X342	List: ML20151X337 ML20151X343 ML20151X348
References
RTR-REGGD-01.097, RTR-REGGD-1.097 GL-82-33, NUDOCS 8808250327
Download: ML20151X343 (2)

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• ...+j SAFETY EVALUATION REPORT COMONWEALTH EDISON QUAD CITIES STATION UNIT NOS. 1 AND 2 DOCKET NOS. 50-254 AND 50-26,5 CONFORMANCE TO REGULATCRY GUIDE 1.97

1.0 INTRODUCTION

Connonwealth Edison was requested by Generic Letter 82-33 to provide a report to NRC describing how the post-accident monitoring instrumentation meets the guidelines of Regulatory Guide (R.G.) 1.97 as applied to emergency response facilities. The licensee responded to Ite'n 6.2 of the generic letter on August 1, 1985. Additional infonnation was provided by letters dated November 4,1985, January 31, 1986, October 6, 1986, May 28, 1987, May 29,1987 and December 17, 1987.

A detailed review and technical evaluation of the licensee's submittals was performed by EGLG Idaho, Inc., under a contract to the NRC, with general supervision by the NRC staff. This work was reported by EG&G in Technical Evaluation Report (TER), "Conformance to Regulatory Guide 1.97: Quad Cities-1/-2,"datedMarch1988(attached). We have reviewed this report and concur with the conclusion that the licensee either confonns to, or has adequately justified deviations from, the guidance of R.G. 1.97 for each post-accident monitoring variable except for the variable neutron flux.

2.0 EVALUATION CRITERIA Subsequent to the issuance of the generic letter, the NRC held regional meetings in February and March 1983 to answer licensee and applicant questions and concerns regarding the NRC policy on R.G.,1.97. At these meetings, it was

. established that the NRC review would only address exceptions taken to the guidance of R.G. 1.97. Further, where licensees or applicants explicitly state that instrument systems confonn to provisions of the regulatory guide, no further staff review would be necessary for those items. Therefore, the review performed and reported by EG&G only addresses exceptions to the guidance 1 of R.G. 1.97. This safety evaluation addresses the licensee's submittels based on the review policy described in the NRC regional meetings and the conclusions of the review as reported by EG&G.

3.0 EVALUATION  !

l We have reviewed the evaluation performed by EG&G contained in the attached '

TER and concur with its bases and findings. The licensee either confonns to, l or has provided an acceptable justification for deviations from the guidance '

of R.G.1.97 for each post-accident monitoring variable except for the variable neutron flux.

8808250327 000816 PDR ADOCK 05000254 P PNU J

i R.G,. L97 recommends Category 1 neutron flux instrumentation to monitor reactivity control. The licensee has provided neutron flux monitoring instrumentation which conforms to the Category 1 recomendations of R.G.1.97 except for environmental and seismic qualification of cables, detectors, and detector drives that are inside the primary containment. The justification provided by the ifcensee for not fully qualifying the neutron flux monitoring instrumentation is that a scram can be verified by monitoring scram relay position, scram valve position, control rod drive scram accumulator pressure, scram discharge volume, makeup flow, RCS pressure, and torus pressure.

The staff does not agree with the licensee's justification. In LOCA situations, monitoring of neutron flux is a direct indication of return to <

criticality rather than a lagging, indirect indication, as provided by the licensee's proposed instrumentation. Thus, the staff finds the licensee's justification unacceptable. ilowever, the staff finds the licensee's justification an acceptable basis for interim operation of the exisiting neutron monitoring instrumentation in conjunction with the above mentioned alternate instrumentation.

The staff has been informed that industry has developed wide range neutron flux monitoring systems that satisfy the Category 1 criteria of R.G 1.97.

Therefore, it is the staff's position that the licensee should evaluate these newly developed systems and install neutron flux monitoring instrumentation which fully complies with the Category 1 criteria of R.G. 1.97.

4.0 CONCLUSION

Based on the staff's review of the enclosed TER and the licensee's submittals, we find that the Quad Cities Station Unit Nos. 1 and 2 design is acceptable with respect to conformance to R.G.1.97, Revision 2 except for the instrumentation associated with the variable neutron flux.

It is the staff's position that information provided by the neutron flux monitoring instrumentation is needed by the operator in the evaluation of proper reactivity control. It is also the staff's position that the licensee should install neutron flux monitoring instrumntation which fully complies with the Category 1 criteria of R.G. 1.97. The existing neutron flux monitoring instrumentation conforms to the Category 1 criteria of R.G.1.97 except for seismic and environmental qualification. Based on the above alternate instrumentation, the staff concludes that the existing neutron flux monitoring instrumentation is acceptable for interim operation pending satisfactory implementation of a fully qualified indication system.

An appropriate implementation schedule will be developed by the Project Manager via discussion with the licensee. Once the schedule is established, the licensee is required to inform the Comission, in writing, of any significant changes in the established completion schedule identified in the staff's safety  ;

evaluation and when the action has actually been completed.

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