B14346, Comment Supporting Draft RG DG-1020, Monitoring Effectiveness of Maint at Nuclear Power Plants

Comment Supporting Draft RG DG-1020, Monitoring Effectiveness of Maint at Nuclear Power Plants

ML20127L246
Person / Time
Site:	Millstone, Haddam Neck  File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	01/15/1993
From:	Opeka J CONNECTICUT YANKEE ATOMIC POWER CO., NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	NRC OFFICE OF ADMINISTRATION (ADM)
References
FRN-57FR55286, RTR-REGGD-1.160, RTR-REGGD-XX.XXX, TASK-DG-1020, TASK-RE 57FR55286, B14346, NUDOCS 9301270060
Download: ML20127L246 (3)

Text

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HARTFORD CONNECTICUT 06141-o270 (203) 66s-5000 January 15, 1993 Docket Nos. 50-211 5_0 f 2.45.

1E13fi 50-423 B14346 Division of Freedom of Information and Publication Services Office of Administration U.S. Nuclear Regulatory Commission Washington, DC 20555 Attention: Regulatory Publications Branch b' -

~f Gentlemen: E N

N Response to NRC Request for Public Comments on the Draft Regulatory Guide DG-1020, " Monitoring the g Effectiveness of Maintenance at Nuclear Po.w_gr Plants" W

Northeast Nuclear Energy Company (NNECO) and Connecticut Yankee Atomici$ower Company (CYAPC0) appreciate the opportunity to comment on the subject Draft Regulatory Guide DG-1020, " Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." This Regulatory Guide proposes to endorse NUMARC Guideline 93-01 (Rev. 2A). As a Validation and Verification (V&V) participant, NNECO and CYAPC0 have contributed extensively in the development of this guideline, and have provided additional input to NUMARC in support of the integrated industry comments. In general, NNECO and CYAPC0 support those views provided by NUMARC, and those of Yankee Atomic Electric Company (YAEC).

In addition, NNECO and CYAPC0 have provided comments on the following points which we consider most significant.

NNECO and CYAPCO's single largest area of concern regarding the Maintenance Rule / Guidelines involves the definition and use of the terms " Maintenance Preventable Functional Failure (MPFF)" and " Repetitive." Special requirements related to goal setting and cause determinations are specified by the guideline on the basis of these terms. NNECO and CYAPC0 consider the current terminology subject to a wide range of interpretation. Viewed in the extreme, this could result in overly programmatic treatment of structures, systems, and components (SSCs) independent of their safety significance.

NNECO and CYAPC0 consider a primary objective of the Maintenance Rule to be the focus of effective maintenance efforts upon SSCs commensurate with their safety significance. Consistent with this interpretation, NNECO and CYAPC0 advocate definition of an MPFF as a failure, at a specific functional 9301270060 930115 PDR REGGD XX.XXX C .PDR q OSM2 REV 4-88

.4 U.S. Nuclear Regulatory Commission B14346/Page 2 January 15, 1993 threshold, based upon the consequences of this failure. This functional threshold should be determined by the individual utility based on the SSC's relative safety significance. It is expected that the appropriate functional threshold would be most often at the train level or higher.

In short, NNECO and CYAPC0 consider prevention of repetitive SSC failure a necessary element of a maintenance rule program. However, the manner and degree to which related efforts are applied, regarding failure analysis and cause determination, thould concentrate on preservation of safety function at the train level.

As stated, Question 2, posed by the NRC, i.e., "is the guidance sufficiently clear that an affirmative demonstration is necessary...," has generated some concern. The question could be construed to mean that specific performance criteria are necessary as a justifying basis for any and all SSCs to be placed in category a(2). So interpreted, this requirement could become counterproductive, in that it would force essentially equivalent treatment of all SSCs independent of safety significance. NNECO and CYAPC0 envision an approach wherein the majority of nonrisk significant, nonstandby SSCs are assessed, via plant level criteria, as part of the periodic assessment process. SSCs would be transferred to category a(1) and/or more effective criteria developed in response to emerging negative performance trends.

The Draft Regulatory Guide DG-1020 is currently scheduled for: final approval in July 1993. At that time, DG-1020 should endorse a new revision to NUMARC 93-01 (i.e., Rev. 3) which integrates Rev. 2A and iall applicable modifications. Endorsement of Rev. 2A as written, in combination with separate modifyina documents, should be avoided.

Overall, NNECO and CYAPC0 view the V&V process as successful in terms of yielding an effective guideline document. However, as total industry experience increases during detailed implementation efforts, many additional issues requiring disposition and/or clarification are expected to arise. To address these issues, NNECO and CYAPC0 stress that:

1. NUMARC and NRC involvement, similar to the V&V, should continue, and that at least one change to the guideline (i.e., Rev. 4) should be scheduled for no later than July 1994 and,

2. Maintenance rule workshops should be conducted for the appropriate industry and NRC personnel to ensure consistent interpretation of acceptable implementation approaches.

. . . ,g U.S. Nuclear Regulatory Commission-B1434 /Page 3 January 15, 1993 If you should have any questions on our comments, please contact'us.

Very truly yours, NORTHEAST NUCLEAR ENERGY' COMPANY CONNECTICUT YANKEE ATOMIC POWER COMPANY

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Executive Vice President cc: A. B. Wang, NRC Project Manager, Haddam Neck Plant J. W. Andersen, NRC Acting' Project Manager, Millstone Unit No. 1 G. S. Vissing, NRC Project Manager, Millstone Unit No. 2-V. L. Rooney, NRC Project Manager, Millstone Unit No. 3 D. H. Jaffe, NRC Project Manager, Millstone Station.

W. J. Raymond, Senior Resident Inspector, Haddam Neck Plant P. D. Swetland, Senior Resident Inspector, Millstone Unit Nos.1, 2, and 3 U.S. Nuclear Regulatory Commission, Document Control Desk 1