ML20247M191

Safety Evaluation Re Denial of Amend Request to Licenses DPR-71 & DPR-62

ML20247M191
Person / Time
Site:	Brunswick
Issue date:	05/25/1989
From:	Office of Nuclear Reactor Regulation
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Shared Package
ML20247M178	List: ML20247M175 ML20247M181 ML20247M191
References
NUDOCS 8906020387
Download: ML20247M191 (4)

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, , < SAFETY EVALUATION Bv THE OFFICE OF NUCLEAR REACTOR REGULATION

, RELATING TO DENIAL OF AMENDMENT REQUEST TO FACILITY OPERATING LICENSE NOS. DPR-71 AND DPR-62

. CAROLINA POWER & LIGHT COMPANY. et al

, BRUNSWICK STEAM ELECTRIC PLANT. 'thlTS 1 AND 2 DOCKET NOS. 50-325 AND 50-324~

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1.0 INTRODUCTION

By letter dated May I',1987, as supplemented June 22, 1987, July 7, 1987.

and March 16,.1989, the Carolina Power & Light Company submitted a request for changes to the Brunswick Steam Electric Plants, Units 1 and 2 Technical-Specifications (TS).

The Amendments would have increased surveillance test and calibration intervals for the Rosemount analog trip unit systems.

2.0 BACKGROUND

In the May 17, 1987 submittal as supplemented' June 22, 1987, the licensee requested an increase in surveillance interval times from one month to six months for channel functional testing and channel calibration associated with the Rosemount analog trip unit systems. This request enveloped the reactor protective system (RPS) instrumentation, the isolation actuation-instrumentation, the emergency core cooling system (ECCS) actuation instrumentation, the anticipated transients without scram (ATWS) recircu-lation pump trip system instrumentation, and the reactor core isolation cooling (RCIC)systemactuationinstrumentation. The June 22, 1987, letter provided a missing page from the May submittal.

'The licensee's present monthly testing and calibration TS requirements for the trip units and refueling outage calibration of the transmitters are based upon General Electric Company Licensing Topical Report NED0-21617-A entitled " Analog Transmitter / Trip Unit System for Engineered Safeguard Sensor Trip Inputs." This topical report was reviewed and approved by the staff on June 27, 1978. The topical report specified trip unit calibration at least four times' per year (Section 6.2.2). However, the report recommended that until the new equipment has accumulated life data, a monthly interval should be utilized. Section 6.1.1 specified trens-mitter calibration of once per operating cycle.

Subsequently, the licensee performed an internal study, reviewed by a consultant, of the surveillance intervals. The impetus for the study was concerns. raised by plant maintenance and operations personnel regarding the numerous and seemingly unnecessary half scrams, half group isolations, and actual ECCS isolations due to Rosemount analog trip unit surveillance.

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The conclusions of the study were that a net reduction in risk (gain in safety) can be realized by increasing the surveillance interval on the Rosemount analog trip _ units from monthly to semi-annually. The results of the study were consistent with the GE topical report NED0-21617-A to the extent'that the surveillance interval'could be increased once life data has been taken and analyzed, but is inconsistent with the GE report as to interval time since the GE report placed an upper limit of four calibrations per year on the trip units. This inconsistency was not addressed in the licensee's study.

The licensee supplemented the May 1, 1987 submittal'by. letter dated July 7, 1987. This submittal revised the significant hazards analysis associated.

with the TS change. The July 7 letter did not significantly. add to the technical justification for a six month testing interval, and it was not utilized in this evaluation.

Cognizant of staff activities on this subject, which will be described later, the licensee revised the application by letter dated March 16, 1989. The revised submittal requested quarterly testing and calibration for the applicable trip units, instead of semi-annual. The only addi-tional technical justification was reference to the staff approved topical report NEDC-30851P-A, entitled " Technical Specification Improvement Analysis for BWR Reactor Protection Systems," and the statement "that document further supports our proposed request to extend the current surveillance interval." Therefore, no new significant technical justi-fication was provided in the March 16 submittal.

During the same period of time that the licensee's application was active, the staff was pursuing generic studies which would justify extending surveillance testing intervals for various trip / actuation systems. These include RPS, rod blocks, ECCS, isolation instrumentation common to RPS and

'ECCS, isolation instrumentation not comon to RPS and ECCS, and ATWS. The staff has issued generic safety evaluations for the first four, as discussed below, and the ' generic safety evaluations for the last two are still in preparation.

In regard to RPS instrumentation, on July 15, 1987 the staff generically approved GE topical report NEDC-30851P entitled " Technical Specifications Improvement Analysis for BWR RPS." This topical report justified testing certain RPS functional units on a quarterly basis versus monthly, and justified increased allowed outage times (A0T). The staff letter also specified that each applicant for proposed TS changes for individual plants must meet three conditions.

On September 22, 1988, the staff generically approved GE topical report NEDC-30851P, Supplement 1, entitled " Technical Specification Improvement Analysis for BWR Control Rod Block Instrumentation." This topical report .

justified testing certain Rod Block functional units on a quarterly basis I versus monthly. The staff letter also specified that each applicant for proposed TS changes for individual plants must meet two conditions.

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3 In connection with ECCS instrumentation, the' staff generically approved GE topical report NEDC-30936-P entitled, "BWR Owner's Group Technical Specifications Improvement Methodology (with Demonstration For BWR ECCS Actuation Instrumentation) Part 2" on December 9,1988. This topical report justified testing certain ECCS functional units on a quarterly basis versus monthly, and justified increased allowed outage times. The staff letter also specified that each applicant for proposed TS changes for individual plants must meet two conditions.

The staff generically approved GE topical report NEDC-30851P, Supplement 2 entitled, " Technical Specification Improvement Analysis for BWR Isolation Instrumentation' Common to RPS and ECCS Instrumentation," on January 6, 1989. The topical report justified testing certain isolation instrumentation functional units common to RPS and ECCS on a quarterly basis verus monthly, and justified increased allowed outage times. The staff letter also specified that each applicant for proposed TS changes for individual plants must meet two conditions.

The staff purposely specified in all the above generic safety evaluations that licensees would have to meet certain conditions for approvals on a plant specific basis. This would permit a more efficient staff review and would not require the staff to review a topical report for each plant.

3.0 EVALUATION ,

The staff reviewed the licensee's application and compared the application to the various generic safety evaluations which were issued. Based upon the staff review, the following represents a summary of deficiencies in the licensee's request for RPS, isolation instrumentation common to RPS/ECCS, and ECCS surveillance intervals.

A. NED0-21617-A specified trip unit calibration of at least four ,

times per year whereas licensee requested six months (applies only to licensee's ori inal application requesting six month surveillance intervals .

B. Insufficient technical justification of testing frequency versus calibration frequency was presented. If the same frequency or different frequency for both are desired, separate justification l for each is necessary.

l C. Conditions of the staff generic safety evaluations were not met.

I D. No statement on licensee's position on A0T was set forth. It is inefficient for the staff to address A0T in a later submittal.

E. Licensee needs to justify increased surveillance intervals for functional units contained in the application but not part of i the generic safety evaluations. l l

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L F.. Licensee needs to address those functional units contained in the generic SE which are not contained in the application.

G. The July 7 '1987 and March 16, 1989 submittals did not provide ey significantly new justification.

The' following represents the staff's evaluation of the licensee's application in so far as isolation instrumentation not common to RPS/ECCS and ATWS functional unit surveillance intervals is concerned: B, D, E F, and G from above are applicable. The staff's generic evaluations.are not yet completed'on this subject.

The staff does not have. underway a generic evaluation for RCIC actuation function unit surveillance interval extensions. The staff would consider extending such intervals if the licensee can demonstrate similarity to '

HPCI actuation functional unit surveillance interval testing extension approved in NED0-30936P or some other technical justification that will stand on its own merit. RCIC was not adequately addressed in the application..

The licensee did not propose changes to rod block instrumentation. Rod block instrumentation is an-integral part of RPS, and the staff recommends that the licensee provide its position on this. The staff considers this a deficiency in the' application.

4.0 CONCLUSION

Based upon the evaluation performed by the staff in the preceding section, the licensee's application of May 1,1987, as supplemented June 22, 1987 July 7, 1987 and March 16, 1989 is denied. The staff is willing to review a new application if the deficiencies described above are corrected.

Principal Contributor: E. Tourigny Dated: May 25,1989 L_1___.___.__._ _ _ _ . _ _ _ _ _ . .