ML20137H430

Forwards Rev 2 or Reg Guide 1.160, Monitoring Effectiveness of Maint at Npps, Which Provides Guidance on Methods Acceptable to NRC for Complying W/Nrc'S Maint Rule 10CFR50.65

ML20137H430
Person / Time
Issue date:	03/21/1997
From:	Rathbun D NRC OFFICE OF CONGRESSIONAL AFFAIRS (OCA)
To:	Gingrich N, Gore A, Murphy R GENERAL ACCOUNTING OFFICE, HOUSE OF REP., SENATE
References
RTR-REGGD-01.160, RTR-REGGD-1.160 CCS, NUDOCS 9704020210
Download: ML20137H430 (3)

Text

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.. e' U lv y  % UNITED STATES j

l ,' s* NUCLEAR REGULATORY COMMISSION

- WASHINGTON, D.C. m1 se..* March 21,1997 l

l t

The Monorable Newt Gingrich i Speaker of the United States House of Representatives Washington, DC 20515

Dear Mr. Speaker:

i Pursuant to Subtitle E of the Small Business Regulatory Enforcement Fairness i Act of 1996, 5 U.S.C. 801, the Nuclear Regulatory Commission (NRC) is j submitting Revision 2 of Regulatory Guide 1.160, " Monitoring the Effectiveness cf Maintenance at Nuclear Power Plants."

Regulatory Guide 1.160 provides guidance on methods acceptable to the NRC staff for complying with the NRC's maintenance rule, 10 CFR 50.65.

~

We have determined that this regulatory guide is not a " major rule" as defined in 5 U.S.C. 804(2). We have confirmed this determination with the Office of Management and Budget.

Enclosed is a copy of Revision 2 of Regulatory Guide 1.160, which will be distributed to affected licensees and other interested parties.  ;

Sincerely,

.J+4bs  !

Dennis K. Rathbun, Director Office of Congressional Affairs

Enclosures:

Regulatory Guide 1.160, Revision 2 Regulatory Analysis I

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• PDR REG 9D 01.160 C PDR

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• • , UNITED STATES i

• f j NUCLEAR REGULATORY COMMISSION WASHINGTON, o.C. M1 l

. . . , c *f March 21, 1997 i

l l The Honorable Al Gore i President of the United States Senate

Washington, DC 20510 l

Dear Mr. President:

I 4

Pursuant to Subtitle E of the Small Business Regulatory Enforcement Fairness Act of 1996, 5 U.S.C. 801, the Nuclear Regulatory Commission (NRC) is .

! submitting Revision 2 of Regulatory Guide 1.160, " Monitoring the Effectiveness I j of Maintenance at Nuclear Power Plants."

' Regulatory Guide 1.160 provides guidance on methods acceptable to the NRC staff for complying with the NRC's maintenance rule, 10 CFR 50.65.

We have determined that this regulatory guide is not a " major rule" as defined

in 5 U.S.C. 804(2). We have confirmed this determination with the Office of i Management and Budget. l l Enclosed is a copy of Revision 2 of Regulatory Guide 1.160, which will be

! distributed to affected licensees and other interested parties. .

Sincerely,

l l f* -p -

j nnis K. Rathbun, Director Office of Congressional Affairs I

Enclosures:

Regulatory Guide 1.160, l Revision 2 4 Regulatory Analysis i

1

• • , UNITED STATES f

Ij*

NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. allEEH001 4 l 4***** March 21, 1997 l I

Mr. Robert P. Murphy General Counsel General Accounting Office

! Room 7175 441 G Street, NW.

Washington, DC 20548

Dear Mr. Murphy:

Pursuant to Subtitle E of the Small Business Regulatory Enforcement Fairness Act of 1996, 5 U.S.C. 801, the Nuclear Regulatory Commission (NRC) is submitting Revision 2 of Regulatory Guide 1.160, " Monitoring the Effectiveness of Maintenance at Nuclear Power Plants."

, Regulatory Guide 1.160 provides guidance on methods acceptable to the NRC staff for complying with the NRC's maintenance rule, 10 CFR 50.65.

1 We have determined that this regulatory guide is not a " major rule" as defined in 5 U.S.C. 804(2). We have confirmed this determination with the Office of Management and Budget.

Enclosed is a copy of Revision 2 of Regulatory Guide 1.160, which will be distributed to affected licensees and other interested parties.

Sincerely, i n

l '/

/ Y ennis K. Rathbun, Director Offic;e of Congressional Affairs

Enclosures:

Regulatory Guide 1.160, Revision 2 Regulatory Analysis

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1. aeog U.S. NUCLEAR REGULATORY COMMISSION Revision 2

/. g March 1997 l

(p**gf) *** OFFICE OF NUCLEAR R REGULATORY GUIDE 1.160 l (Draft was DG-1061) l i MONITORING THE EFFECTIVENESS OF

! MAINTENANCE AT NUCLEAR POWER PLANTS i I

! A. INTRODUCTION consistent with the NRC's defense in-depth philoso-phy. Maintenance is also important to ensure that de-The NRC published the maintenance rule on sign assumptions and margins in the original design ba-July 10,1991, as Section 50.65, " Requirements for l sis are maintained and are not unacceptably degraded.

Monitoring the Effectiveness of Maintenance at Nu-Therefore, nuclear power plant maintenance is clearly clear Power Plants," of 10 CFR Part 50, " Domestic Li-important in protecting public health and safety.

5 censing of Production and Utilization Facilities." The NRC's determination that a maintenance rule was Paragraph (a)(1) of 10 CFR 50.65 requires that needed arose from the conclusion that proper mainte- Power reactor licensees monitor the performance or nance is essential to plant safety. As discussed in the condition of SSCs against licensee-established goals in regulatory analysis for thisrule,1 thereis a clearlinkbe. a manner sufficient to provide reasonable assurance tween effective maintenance and safety as it relates to that such SSCs are capable of fulfilling their intended such factors as the number of transients and challenges functions. Such goals are to be established commensu-(s to safety systems and the associated need for operabil. rate with safety and, where practical, take into account ity, availability, and reliability of safety equipment. In industry-wide operating experience. When the perfor-addition, good maintenance is also important in provid. mance or condition of an SSC does not meet estab-ing assurance that failures of other than safety-related lished goals, appropriate corrective action must be tak-structures, systems, and components (SSCs) that could en. For a nuclear power plant for which the licensee has initiate or adversely affect a transient or accident are submitted the certifications specified in 10 CFR minimind. Minimizing challenges to safety systems is 50.82(a)(1) (i.e., plants undergoing decommissioning),

Paragraph (a)(1) of 10 CFR 50.65 applies only to the INRC Memorandem to All Commissioners fmm L Taylor on "Mainte- extent that the licensee must monitor the performance mance Rulemaking,* Junc 27,1991. Copies are available forinspection or or condition of all SSCs associated with storing, con-N,"NhfngYonN,tNR a d ss is si s op trolling, and maintaining spent fuel in a safe condition, Washington, DC 20555; phone (202)634-3273; fax (202)634-3343. in a manner sufficient to provide reasonable assurance USNRC REOULATORY GUIDES The ymnes .o mound m to sono ing een twood divisare Regulatory Guuses .e maimd e osacree and make avesetdo e to putdic audi mlorme.

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APPENDIX A

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l DRAFT REGULATORY ANALYSIS j 2 {

FOR THE IMPLEMENTATION OF 10 CFR 50.65, I l 3

" REQUIREMENTS FOR MONITORING THE EFFECTIVENESS l 4 0F MAINTENANCE AT NUCLEAR POWER PLANTS"

! 5 6 $UMMARY l

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8 -

The NRC staff proposes to endorse an industry guidance document

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9 (NUMARC 93-01, Revision 2A, dated July 9,1992), " Industry Guideline for i 10 Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," to

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11 implement i 50.65, " Requirements for Monitoring the Effectiveness of

!l 12 Maintenance at Nuclear Power Plants," of 10 CFR Part 50, " Domestic Licensing j, 13' of Production and Utilization Facilities." This regulatory analysis was j 14 developed to support the NRC staff's decision.

j 15 The maintenance rule requires comercial nuclear power plant licensees l 16 to monitor the effectiveness of maintenance activities for safety-significant l 17 plant equipment in order, to minimize the likelihood of failures and events j 18 caused by the lack of effective maintenance. The provisions of the mainte-19

{ nance rule and NUMARC-93-01 are described and discussed in the text of Draft j 20 Regulatory Guide DG-1020, " Monitoring the Effectiveness of Maintenance at 21 Nuclear Power Plants."

22 The NRC staff proposes to endorse an industry guidance document to 23 implement the maintenance rule in order to maximize the leadership role of the 24 industry in the area of maintenance. The performance-based, results-oriented 25 characteristics of the maintenance rule make industry cooperation desirable to 26 realize the full benefits of the rule. The NRC staff originally considered 27 adopting its own regulatory guidance without reference to industry guidance.

28 However, this option was rejected in favor of endorsing NUMARC-93-01.- -Details 29 of the staff's original effort are contained in Reference 1.

30 NUMARC-93401 provides guidelines to utilities on identifying structures, 31 systems, and components (SSCs) within the scope of NRC's maintenance rule.

32 Appropriate performance criteria are to be established at the plant, system, 33 train, and, in rare cases, component levels. Performance criteria are to be 34 compared to actual SSC performance to determine the need for additional speci-A-1

i l 1 fic goals and monitoring. A basic concept of the industry guidance is that 2 all SSCs within the scope of the rule will be covered by the preventive main-3 tenance provisions (10 CFR 50.65(a)(2)] of the rule, and in addition, some 4 SSCs will be subject to goal setting and monitoring as described in 10 CFR 5 50.65(a)(1). Further discession of the provisions of the NUMARC guidance may l

~6 be found in Appendix B, "Backfit Analysis," to this guide. I 7 Costs and benefits associated with the implementation of the maintenance 8 rule are contained in the regulatory analysis that was provided for tne rule ,

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9 (Ref. 2). In addition, NUMARC plans to assemble cost and benefit information l

. 10 'as part of a validation and verification program for their proposed guidance l 11 document.

12 The maintenance rule is to become fully effective on July 10,'1996.

13 14 1. STATEMENT OF THE PROBLEM 15 16 1.1 Backaround i 17 18 On July 10, 1991, the Comission published (56 FR 31324) 10 CFR 50.65, 19 " Requirements for Moultoring the Effectiveness of Maintenance at Nuclear Power 20 Plants" (may be referred to hereafter as "the maintenance rule" or "the 21 rul e") . Along with the rule, the Comission also published (56 FR 31306 to 22 31323) supplementary information to explain its decision.

l 23 The NRC staff was assigned the task (item III of the Staff. Requirements j 24 Memorandum (SRM) dated June 28,1991, Ref. 3) to develop implementing regula-25 tory guidance for the rule. The SRM indicated that the Comission desired to

. 26 be closely involved and directed the staff to keep the Comission informed 27 about the development of the regulatory guidance.

28 On August 16, 1991, the industry, through the Nuclear Management and 29 Resources Council (NUMARC), sent a letter to the Chairman of the NRC (Ref. 4) 30 expressing a desire to develop ar. k.6::try guidance document for implementing 31 the rule. NUMARC suggested that the NRC staff could then endorse that docu-32 ment in a regulatory guide. Shortly thereafter, the NRC Executive Director 33 for Operations (ED0) organized a steering group of NRC managers to coordinate 34 and supervise the NRC staff efforts.

35 A public meeting of the steering group and NUMARC representatives was 36 held on August 21, 1991. Criteria for an acceptable industry guidance docu-A-2

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' ment, schedule, and coordination of effort were discussed. The NRC staff 2

representatives indicated that the staff would proceed to develop regulatory j 3

guidance in parallel with, but independent of, the NUMARC effort. This 4

• parallel effort was undertaken in order to give the staff the necessary 5

insights into the proper content of the regulatory guidance and to provide an 6

alternative if the NUMARC guidance could not be adopted for some reason.

, 7 An NRC staff working group was organized by the NRC Office of Research I 8

(RES) to develop a draft regulatory guide. Drafts of both the NUMARC guidance l 9

document and the staff's draft regulatory guide were completed and placed in l 10 the NRC public document room during the next several months. A number of i 11 l

public meetings were held to discuss the content and progress of the industry 12 guidance document.

13 The NRC staff working groJp essentially completed work on their draft

! 14 regulatory guide in early June 1992. On June 12, 1992, the steering group met 15 4 with NUMARC and announced that the NUMARC guidance document could be endorsed 16 by the NRC if agreement could be reached on a number of issues. A second NRC 17 staff working-level task group was. organized by the Office of the EDO to meet 18 with NUMARC working-level representatives in a series of public meetings to 19 resolve the remaining issues associated with the planned endorsement of the 20 NUMARC guidance. On July 10, 1992, HUMARC submitted a draft guidance document 21 (NUMARC-93-01, Revision 2A) entitled " Industry Guideline for Monitoring the 22 Effectiveness of Maintenance at Nuclear Power Plants." This document 23 satisfied the NRC's primary concerns.

24 On July 17, 1992, the Commission sent an SRM to J. M. Taylor (Ref. 5) 25 - indicating their concurrence with the staff's proposed approach, as described 26 in SECY-92-229 dated June 25, 1992 (Ref. 6). Also on July 17, 1992, the 27 Deputy EDO (acting as chairman of the steering committee) sent a letter to 28 NUMARC (Ref. 7) stating that the industry guidance would be acceptable pending 29 resolution of a few clarification issues, as well as the industry's 30 verification and validation (V&V) effort.

31 The V&V effort is being initiated by NUMARC at several plants to test 32 the guidance document on several representative systems (see Ref. 8). V&V 33 results might lead to changes in the guidance based on lessons learned by 34 trial implementation at the plants. The NRC staff is participating in the V&V 35 effort; the V&V effort is intended to be complete in January 1993.

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4 j 1 The final regulatory guide to implement the industry guidance is 2 scheduled to be issued by June 30, 1993.

3 l 4 1.2 Discussign 5

6 This regulatory analysis was developed to support implementation of j 7 regulatory guidance that endor:c: MU$it.RC-.93-01, Revision 2A, dated July 9, 8 1992. The purpose of this regulatory analysis is to document the basis for l 9 the staff's decision to endorse this industry guidance.

10 The regulatory requirement (the maintenance rule) is in place and will 11 take effect on July 10, 1996. An analysis of costs and benefits was prepared 12 as part of the regulatory analysis for the rule, and therefore, no separate 13 cost / benefit analysis has been prepared for the regulatory guide. NUMARC is 14 assembling cost and benefit figures as part of their V&V program and these 15 will be provided when they are available.

16 17 2. OBJECTIVES 18 19 The objectives of the regulatory guidance are to explain the concepts of 20 the rule, provide illustrations and examples, provide for con'sistent implemen-21 tation by licensees, provide for consistent audit and inspection by both 22 industry and the NRC, and define acceptable norms for implementation.

23 24 3. ALTERNATIVES 25 26 The alternatives available to the staff are either to endorse an indus-27 try guidance document or to prepare a regulatory guide developed by the staff 28 without reference to industry guidance.

29 30 4. CONSE0VENCES 31 32 41 Costs and Benefits of Alternatives 33 34 Costs and benefits of the maintenance rule are presented in the regula-35 tory analysis for the rule (Ref. 2). The results of that analysis are

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36 summarized in Appendix B to this guide. NUMARC is accumulating cost and bene-A-4

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, ,' I fit estimates for their guidance document from the utilities participating in 1 2 the V&V program. 'These estimates will be made available to the NRC within the 4 -

3 next few months. I

4 The staff is relying on the regulatory analysis for the rule as an

- 5 estimate of costs and benefits associated with adopting the NUMARC guidance. l l 6 Neither the original regulatory guide developed independently by the staff nor j 7 the NUMARC guidance will directly affect these costs and safety benefits.

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! 9 4.2 Imoacts on other Reauirements 10  !

i l Il The maintenance rule, as well as its implementing guidance, could have a )

i -12 wide but varying impact on other existing requirements. The results of f 13 monitoring the effectiveness of maintenance may indicate that appropriate i 14 changes to other requirements should be considered.'

l 15 One specific objective in implementing a regulatory guide that endorses I 16 a guidance document produced by the nuclear industry is to avoid duplication  ;

17 of effort on the part of licensees by relying on their knowledge and experi-l 18 ence. The objective is to achieve a synesistic relationship between the i 19 implementation of the maintenance rule and the other applicable requirements.

i 20 For example, licensee maintenance efforts could, with some exceptions, reduce i 21 the effects of equipment aging. At the same time, the effective maintenance

! 22 programs that are specifically developed to mitigate aging should directly 23 increase the effectiveness of each licensee's maintenance. efforts.

I 24 l' '

25 26 4.3 timitations of the Guidance h 27 The basis for the staff's decision to endorse a guidance document 28 prepared by the industry is, to some extent, dictated by the characterization 29 of the rule as performance-based and results-oriented. The requirements of 30 the rule will, be met if systems, structures, and components within its scope 31 are being effectively maintained to ensure that they will parform their 32 intended functions. Intentionally, little detail is offered in the rule con- '

33 cerning the details of its implementation. Thus, it is imperative that the 34 NRC and industry both understand and support the implementation guidance.

35 Implementation guidance should be instructive but not restrictive because 36 maintenance results, not maintenance procedures, are the focus of the rule.

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1 Existing licensee and industry programs are expected to be utilized to the 2 extent possible. The full and enthusiastic cooperation and leadership of the 3 industry would help to achieve maximum benefits from the rule. These objec-

- 4 tives, the benefits of which are not easily quantified, are considered to be ,

5 fundamentally important to the successful implementation of the rule.

6 The staff worked closely with NUMARC as they developed their guidance i 7 document to ensure that the requirements and intent of the maintenance rule l

8 would be addressed. Accordingly, at this time, tha proposed regulatory guide endorses the NUMARC guidance without modification. It is expected that the 9

10 V&V program will result in changes to the NUMARC guidance. If, as expected,

! 11 changes are needed and are shown to be acceptable to the staff, then no 12 changes or additions to the NRC regulatory guide will be necessary as a result 13 of the V&V program.

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15 5. RECOMMENDED ACTION 16 17 At the present time, the NRC staff proposes to publish regulatory 18 guidance that endorses NUMARC-93-01 without modification. The staff will 19 actively participate in the industry-sponsored V&V program in order to confirm 20 its decision. The performance-based, results-oriented charactistics of the 21 maintenance rule make industry cooperation vital to successful implementation 22 of the rule.

23 The NRC staff originally wrote its own regulatory guidance without 24 reference to industry guidance in order to provide insights to the NRC staff 25 and to provide backup in case the industry guidance could not be endorsed.

26 This NRC guidance document was not adopted, and the NRC staff decided to 27 endorse NUMARC 93-01. Details of the staff's original effort are contained in 28 Reference 1.

29 The NRC staff's regulatory guidance and the industry guidance each 30 provide suitable implementing guidance to the industry. Either is consistent 31 with the intent of the rule and the regulatory analysis that was prepared to 32 support the rule.

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, 1 6. IMPLEMENTATION i r

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3. 6. I' Schedule l 4 1 5 HILESTONE DATE '

6 Regulatory Guide 11/92 . -

l 7 Published for Public 8 Comment 9 Industry V5V Program To 1/93 10 Test Industry Guidance 11 Complete 12 OMB Approval of Infor- 1/93 13 mation Collection 14 Requirements under the 15 Paperwork Reduction Act 16 Final Regulatory Guide 6/93 17 Published 18 NRC Workshops on 6/93 through 6/96 19 Regulntory Guidance 20 ph 21 Maintenance Rule Takes Effect 7/96 22

, 23 24 6.2 Relation to Other Existino or Proposed Recuirements

, 25 26 Future initiatives that, are related to maintenance should be compared 27 with the performance-based, results-oriented approach of the maintenance rule 28 in order to identify potential conflicts.

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I REffRENCES 2

3 1. G. Zigler et al., " Regulatory Analysis for the Draft NRC Regulatory

4 Guide for Implementing the i 50.65 Rule," Science and Engineering A'sso-5 ciates Report, SEA 91-554-02-A

2, Albuquerque, New Mexico, September 6 1992.*

7 . __

8 2. J. Taylor, NRC Memorandum to All Commissioners Entitled " Maintenance 9 Rulemaking," June 27,1991 (Final Maintenance Rule, Statement of 10 Considerations, and Regulatory Analysis enclosed).*

11 j 12 3. NRC Memorendum from S. J. Chilk to J. M. Taylor, Subject " Staff Reguire-13 ments - Affirmative / Discussion and Vote," Item III, June 28, 1991.*

14

15 4. Letter from B. Lee, Jr., NUMARC, to I. Selin, NRC, August 16, 1991.*

16 17 5. Memorandum from S. J. Chilk, NRC, to J. M. Taylor, NRC,

Subject:

"SECY-18 92-229 - Implementing Guidance for the Maintenance Rule,10 CFR 50.65,"

19 July 17, 1992.* )

20 21 6. NRC Policy Issue SECY-92-229, from J. M. Taylor to the Commissioners, 22

Subject:

" Implementing Guidance for the Maintenance Rule,10 CFR 23 50.65," June 25, 1992.*

24 25 7. Letter from J. H. Sniezek, NRC, to T. Tipton, NUMARC, July 17, 1992.*

26 27 8. NRCMemorandumfromOwenRothbergtoRobertL.BaYrdatedAugust27, 28 1992, " Report of Meeting With NUMARC and Nuclear Utility Representatives 29 Tr :oscuss NUMARC's Verification and Validation Program for the Mainte-

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30 nance Rule (10 CFR 50.65)."*

31

• Copies are available for inspection or~ copying for a fee from the NRC 32 Public Document Room at 2120 L Street NW., Washington, DC; the PDR's mailing 33 address is Mail Stop LL-6, Washington, DC 20555; phone (202)634-3273; fax 34 (202)634-3343.

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I BIBLIOGRAPHY O2 3 Ericson, D. M., et al. (Eds), " Analysis of Core Damage Frequency: Internal l

)

4 Events Methodology," NUREG/CR-4550, Volume 1, Revision 1, Jandary 1990.

5 6 Lofgren, E. V., et al., "A Process for Risk-Focused Mair.tenar.ce," NUREG/CR-7 569!i prepared for the NRC by Science Applications International Corporation, l

8 March 1991.

9

i 10 Meyer, M. A., and J. M. Booker, " Eliciting and Analyzing Expert Judgement,"

i 11 NUREG/CR-5424, prepared for the NRC by Los Alamos National Laboratory, January

12 1990. j i 13 {

14 Mosleh, A., V. M. Bier, and G. Apostolakis, " Methods for the Elicitation and l

15 Use of Expert Opiniun in Risk Assessment," NUREG/CR-4962, prepare' for the NRC l 16 by Pickard, Lowe and Garrick, Inc., August 1987.

17 18 Travis, R., et al., " Generic Risk Insights for Westinghouse and Combustion 19 Engineering Pressurized Water Reactors," prepared for the NRC by Brookhaven 20 National Laboratory, NUREG/CR-5637, November 1990.

21 22 Travis, R., J. Taylor, and J. Chung, " Generic Risk Insights for General 23 Electric Boiling Water Reactors," NUREG/CR-5692, prepared for the NRC by 24 Brookhaven National Laboratory, May 1991. -

25 26 Vesely, W. E., et al., " Measures of Risk Importance and Their Applications,"

27 NUREG/CR-3385, prepared for the NRC by Battelle Columbus Laboratories, July  ;

28 1983.

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