ML20195J667
| ML20195J667 | |
| Person / Time | |
|---|---|
| Issue date: | 06/02/1999 |
| From: | Travers W NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | Powers D Advisory Committee on Reactor Safeguards |
| References | |
| ACRS-GENERAL, NUDOCS 9906210078 | |
| Download: ML20195J667 (5) | |
Text
F'
- n q\\
UNITED STATES
.g NUCLEAR REGULATORY COMMISSION E
I WASHINGTON, D.C. 30806 0001
%,4,,,,
June 2, 1999 si Dr. Dana A. Powers, Chairman I
Advisory Committee on Reactor Safeguards U.S. Nuclear Regulatory Commission j
Washington, DC 20555-0001
SUBJECT:
PROPOSED FINAL REVISION TO 10 CFR 50.65,
- REQUIREMENTS FOR 4
MONITORING THE EFFECTIVENESS OF MAINTENANCE AT NUCLEAR POWER PLANTS"
Dear Dr. Powers:
I am forwarding the staff's response to the recommendations of the Advisory Committee on Reactor Safeguards (ACRS) on the proposed final revision to 10 CFR 50.65 transmitted by your letters of April 14 and May 11,1999.
I.
Staff's Response to ACRS Recommendations of April 14,1999.
1.
ACRS Recommendation:
)
We recommend that the staff proceed with the proposed revision to 10 CFR 50.65.
Response
The staff proceeded with the proposed revision, which was issued as SECY-99-133 on May 21,1999.
I 2.-
ACRS Recommendation:
We recommend that the staff hold one or more workshops, as needed, for the licensees and regional staff to ensure consistency in implementing the -
requirements of the proposed rule.
Response
The staff agrees that these workshops would be beneficial. NRC and Nuclear Energy Institute / industry workshops held during the development and promulgation of industry guidance to support initialimplementation of the maintenance rule played a vital role in ensuring consistency in industry implementation and NRC inspection of the rule. The staff expects that holding one or more workshops will achieve similar benefits of increasing the efficiency and effectiveness of NRC activities associated with implementation of the final rule in a consistent manner. The staff will realign resources to support the workshop process.
L - - / P T 50 N/E u g ] M "/ h C([
.4
.or 9906210078 990602
/\\/
/
GENERAL PDR 7
f.
f.
2
. 3.
ACRS Recommendation:
/ ;;
We support the staff's plan to issue the revised Regulatory Guide (RG) 1 160 for industry use before implementing the revised rule.
Response
The staff will proceed with revising RG 1.160. The staff has recommended to the Commission that the revised rule become effective 120 days after issuance of the revised regulatory guide.
II.
Staff's Response to ACRS Recommendations of May 11,1999.
1.
ACRS Recommendation:
We reviewed a previous version of 10 CFR 50.65 during our 461" meeting and issued a report dated April 14,1999, in that report, we stated that both high safety significant structures, systems, and components (SSCs) and low safety dgnificant SSCs need to be addressed by the Maintenance Rule. We note that the usual classification of SSCs as high or low safety significant is based on probabilistic risk assessments (PRAs) of typical configurations at power. A different configuration or a different mode of operation may change the relative rankings of the SSCs.
Response
1 The staff agrees with the committee's observation and has prepared draft regulatory guidance with acceptable methods for performing premaintenance safety assessments of configurations during power operation or shutdown operation. This guidance will be incorporated in the revision to RG 1.160 as described in the response to ACRS recommendation 1.3 mentioned previously.
2.
ACRS Recommendation:
We recommend the following modification to language proposed by the staff since our April 14,1999, report:
Scope of the assessment may be limited to structures, systems, or components that a risk-informed evaluation process has shown to be significant to public health and safety for the proposed configuration.
Response
The staff had discussed the proposed language for the final rule during the May 5,1999, Commission meeting. Although the ACRS proposed modified rule language in its May 11,1999, letter to the Chairman, the Commission decided in i
an SRM dated May 13,1999, to endorse the modified language on " slide 8".
During the Commission presentation, the importance of the technical content of l
V 3
the regulatory guide being developed was highlighted, to addressing the ACRS concems as part of the develo,and the staff is c pment process.
- 3.
MS Recommendation:
i We recommend that the configuration risk management program (CRMP) in j
= RG 1.177 not be adopted.
Response
The staff will carefully consider this recommendation. The staff has taken actions to provide regulatory guidance that describes an acceptable risk-informed scope for premaintenance assessments. This risk-informed assessment scope will be incorporated into the revised RG 1.160 and is intended to include consideration for assessing configurations involving SSCs that are not modeled in the PRA or otherwise determined to be highly safety significant. The staff will work with ACRS, the Committee To Review Generic Requirements, other staff organizations, and the nuclear industry to complete formulation of the most appropriate assessment scope.
4.
ACRS Recommendation:
We believe that licensees need to take responsibility for evaluating and managing the risk associated with taking multiple SSCs out of service.' Plant operators should not be confronted with inadequately evaluated plant configurations. This [ problem) can be avoided by appropriately evaluating the actual configuration. We note that currently operating plants have not been designed with the intent of performing on-line maintenance, but recognize that technology is now available to manage appropriately the risk associated with on-line maintenance. Therefore, we support the industry practice of performing on-
)
- line maintenance, as long as this is done safely.
Response
The staff strong!y agrees that licensees must take responsibility for safely evaluating and managing the risk associates. with taking multiple SSCs out of service. The stait also agrees that inadequately evaluated plant cor/igurations must be avoided but believes that this task can be accomplished within an appropriately risk-informed assessment scope.
F
?
l' 4
l l
Please let me know if the Committec has any further questions or comments on the proposed rule.
d Sincerely, VPiginal eicned tv Frank J. Miraglia b William D. Travers Executive Director for Operations cc-Chairman Jackson Commissioner Dieus Commissioner Diaz Commissioner McGaffigan Commissioner Merrifietri SECY DISTRIBUTION:
Central File IQMB R.F.
NRR Mail Room (Ticket # G19990207)
M. Knapp F. Miraglia P. Norry J. Biaha S. Bums Thadani, RES Mitchell, OEDO ACRS File B. Sheron J. Silber Public DOCUMENT NAME: A:\\ACRS.WPD
- See previous concurrence To rer.lve a copy of this document, Indicate in the box: "C" = Copy without enclosures *E" = Copy with enclosures "N" = No copy OFFICE IQMB:DIPM r3 SCtQMB 6
BC:lOMB D: LPM TECH ED U
NAME PABatmain:cet/#A')R @ / rela TRQuay T7!4 BABoger TJ b A('&,.
DATE 05/2(/99
'/l 06/M/99 05/31/99 MH\\%
05/23'99 t/# '05/N//99 OFFICE ADIP 4:!P,1 qbtf D:NRR
,e a EbO 4
4 NAME WFKane rJ/ D T6JCollins ML WraveM w
~
DATE 05/M'/99 #
y 056 7'99
'lpR d99 05/ /99 05/ /99 l
OFFICIAL RECyRD COPY
[. '
.e' 4
Please let me know if the Committee has any further questions or comments on the proposed rule.
a.
l Sincerely, William ravers N
Executive Director q
for Operations g
l cc:
Chairman Jackson l
CommissionerDieus Commissioner Diaz l
Commissioner McGaffigan l
Commissioner Merrifield SECY l
l l
l a
/
g UNITED STATES ~
M
- /
NUCLEAR REGULATORY COMMISSION
{
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS WASHINGTON, D. C. 20005 April 14,1999
/
4 The Honorable ShirleyAnn Jackson i
Chairman U. S. Nuclear Regulatory Commission, Washington, D.C. 20555-0001 4
)
Dear Chairman Jackson:
SUBJECT:
PROPOSED FINAL. REVISION TO 10 CFR 50.65, ' REQUIREMENTS FOR MONITORING THE EFFECTIVENESS OF MAINTENANCE AT NUCLEAR POWER PLANTS" During the 461st meeting of the Advisory Committee on Reactor Safeguards, April 7-10,1999, we completed our review of the proposed final revision to 10 CFR 50.65 and proposed revision 3 to Regulatory Guide 1.160, " Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." During our review, we had the benefit of discussions with representatives of the NRC staff and the Nuclear Energy institute (NE4). We also t.sd the benefit of the documents referenced.
Conclusions and Recommendations:
1.
We recommend that the staff proceed with the proposed revision to 10 CFR 50.65.
2.
We recommend that the staff hold one or more workshops, as needed, for the licensees and regionalstaff to ensure consistency in implementing the requirements of the revised rule.
i 3.
We support the staff's plan to issue the revised Regulatory Guide 1.160 for industry use before implementing ae revised rule.
Discussion-Both the staff and the industry agree that 10 CFR 50.65 needs to be revised to ensure thsi the safety assessments described in the current paragraph (a)(3) are recognized as requirements, that is, at a minimum 'should* needs to be changed to "shall." The language in the new paragraph (a)(4) clarifies the obvious intent of the original rule.
We support the staff's position that the safety assessment should consider all components that are taken out of service at the same time. NEl has suggested that the scope of the revised rule be limited to high safety significant structuros, systems, and components (SSCs), which are ranked using the guidance specified in NUMARC 93-01, " Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." It is not apparent that components EDO --G19990207 h-QOhf0$(.
V=
.y.
=
-2 y
ranked as having low safety significance will continue to be oflow safety' significance under all J
the configurations that can occur when multiple components are simultaneously taken out of service. In the proposed revision 3 to Ragulatory Guide 1.160, the staff pr9vides guidance for assessing the safety significance of plant configurations that arise in the course of doing maintenance. The proposed rule and revision 31o Regulatory Guide 1.160 are sufficiently
- flexible that the assessments can be performed without imposing excessive burden on the Econsees.
The language in the revised rule expaniis the scope of the rule from monitoring or preventive
. maintenence activities to a wider range of maintenance activities. We support this change because there is no reason to require safety assessments for monitoring or preventive maintenance activities and not require such assessments for other types of planned maintenance activities.' Expanding the scope of the rule to include such assessments is consistent with the original purpose of the rule.
The other substantive change to the rule is the addition of the introductory sentence clarifying that the rule applies during all conditions of plant operation, including normal shutdown operations. As we have stated on several occasions, we believe shutdown operations of nuclear pewsr plants deserve increased regulatory attention.
The industry has requested guidance for implementing the regulrdments of the revised rule. It is
, essential that this gu! dance be developed with public input in advance of adopting the revised rule. We support the staffs proposal to issue this guidance 120 days before implementing the revised rule and to hold one or more workshops, as needed, for the licensees and regional staff
' to ensure consistency in the implementation of the revised rule.
. The increasing use of on-line maintenance,if properly managed, can provide both cost reductions and improvements in safety. A better definition of the term " safety related' has been i
identified as a critical step in the development of a risk-informed 10 CFR Part 50. The potential
. multiplicity of configurations that result from on-line maintenance is one of the elements that must be considered in the development and use of such a definition.
Sincerely,
\\ owa d.
Wt@
Dana A. Powers Chairman
References:
1.
Memorandum dated March 9,1999, from Bruce A. Boger, NRR, to Addressees, transmitting Final Revision to 10 CFR 50.65 to Require Licensees to Perform Pre-Maintenance Assessments.
?
4
o a
r.
l 3
2.
U. S. Nuclear Regulatory Commission, Proposed Revision 3 to Regulatory Guide 1.160,
" Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," dated March 5, 1999.
3.
Letter dated December 14,1158, from Anthony R. Pietrangelo, Nuclear Energy Institute, to John C. Hoyle, Secretary of the Commission,
Subject:
ladustry Comments on Proposed Rulemaking to 10 CFR 50.65, Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants.'
4.
SECY-98-165, Memorandum dated July 2,1998, from L. Joseph Callan, Executive l
Director for Operations, NRC, for the Commissioners,
Subject:
Proposed Revision to 10 CFR 50.65(a)(3) to Require Licensees to Perform Safety Assessments.
5.
Memorandum dated September 3,1998, from John C. Hoyle, Secretary of the Commission, to L. Joseph Callan, Executive Director for Operations, NRC,
Subject:
Staff Requirements - SECY-98-165 - Proposed Revision to 10 CFR 50.65(a)(3) to Require Licensees to Perform Safety Assessments, i
6.
Memorandum dated December 17,1997, from John C. Hoy'o, Secretary of the Commission, to L. Joseph Callan, Executive Director for Operations, NRC, and Karen D.
Cyr, General Counsel, NRC,
Subject:
Staff Requirements: SECY-97-173 - Potential Revision to 10 CFR 50.65(a)(3) of the Maintenance Rule to Require Licensees to Perform Safety Assessments.
7.
Letter dated January 22,1999, frorn Ralph E. Beedle, Nuclear Energy institute, to Shirley Ann Jackson, Chairman, NRC, regarding proposed revision to the maintenance rule and 10 CFR 50.59.
8.
Nuclear Energy Institute, NUMARC 93-01, Revision 2, " Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," April 1996.'
9.
I.etter dated November 25,1998, from Joe F. Colvin, Nuclear Energy Institute, to Shirley A. Jackson, Chairman, NRC, regarding Stakeholder meeting on November 13,1998.
l 10.
Letter dated March 23,1999, from Winston & Strawn to U. S. NRC Commissioners, regarding Proposed Revision to Maintenance Rule.
11.
Letter dated March 17,1999, from R. E. Beedle, Nuclear Energy Institute, to Shirley Ann Jackson, Chairman, NRC, regarding concerns on proposed revision to 10 CFR 50.65, the maintenance rule.
12.
Report dated April 18,1997, from R. L. Seale, Chairman, ACRS, to Shirley Ann Jackson, Chairman, NRC,
Subject:
Establishing a Benchmark on Risk During Low-Power and Shutdown Operations."
13.
' Report dated April 23,1996, from T. S. Kress, Chairman, ACRS, to Shirley Ann Jackson, Chairman, NRC,
Subject:
Probabilistic Risk Assessment Framework, Pilot Applications, and Next Steps to Expand the Use of PRA in the Regulatory Decision-Making Process.
~
mee
~
UNITED STATES g
NUCLEAR REGULATORY. COMMISSION g
ADVl60RY COMMITTEE ON REACTOR SAFEGUARDS a
WASHINGTON, D. C. 20606
\\
- May 11,1999 i
. The Honorable Shirley Ann Jackson Chairman U.S. Nuclear Regulatory Commission Washington, D.C.'20555-0001
Dear Chairman Jackson:
SUBJECT:
MODIFIED PROPOSED FINAL REVISION TO 10 CFR 50.65,
- REQUIREMENTS FOR MONITORING THE EFFECTIVENESS OF MAINTENANCE AT NUCLEAR POWER PLANTS' During the 462nd meeting of the Advisory Con;mittee on Reactor Safeguards, May 5-8,1999, we reviewed the modified proposed final revision to 10 CFR 50.65 and proposed revisions to Regulatory Guide 1.160," Assessing and Managing Risk Before Maintenance Activities at Nuclear Power Plants." During our review, we had the benefit of discussions with representatives of the NRC staff and Nuclear Energy Institute (NEI). We also had the benefit of the documents referenced.
We reviewed a previous version of 10 CFR 50.65 during our 461st meeting and issued a report dated April 14,199g. In that report, we stated that both high safety significant structures, systems, r,nd components (SSCs) and low safety significant SSCs need to be addressed by the Maintenance Rule. We note that the usual classification of SSCs as high or low safety significant is based on probabilistic risk assessments (PRAs) of typical configurations at power. A different configuration or a different mode of operation raay change the relative rankings of the SSCs.
Since our April 14,1999 report, the staff has proposed to add the following language to paragraph (a)(4) of 10 CFR 50.65: " Scope of the assessment may be limited to structures, systems, or components that a risk-informed evaluation process has shown to be significant to public health a~ nd safety." We recommend the following modification to the staffs proposed language:
" Scope of the assessment may be limited to structures, systems, or components that a risk-informed evaluation process has shown to be significant to public health and safety for the proposed configuration."
The staff also stated that it is considering revising Regulatory Guide (RO) 1.160 to adopt the configuration risk mana)gement program (CRMP) in RG 1.177, 'An Appre.ach for Plant-Specific, Risk-informed D cisionmaking: Technical Specifications." The program riescribed under Key Component i of Section 2.3.7.2 of RG 1.177 requires an assessment of all SSCs modeled in the
%CN 70061
).
-2 j
,.}
licensee's PRA in addition to all SSCs considered high safety significant that are not modeled in the PRA. This program, however, does not include a discussion of other SSCs. The CRMP was designed for extending outage time as aBowed in the technical specifications and may not be appropriate for managing the risk of maintenance acuvities. Since the number orlow safety significant SSCs modeled in licensees' PRAs may vary widely, we are concerned that there may be configurations of SSCs out of service for maintenance that would not have received an assessment. We recommend that the CRMP in RG 1.177 not be adopted.
We believe that licensees need to tale responsibility for evaluating and managing the risk associated with Sking multiple SSCs out of service. Plant operators should not be confronted with inadequately evaluated plant configurations. This can be avoided by appropriately evaluating the actual configuration. We note that currently operating plants have not been designed with the intent of performing on-line maintenance, but recognize that technology is now available to manage appropriately the risk associated with on-line maintenance. Therefore, we; support the industry practice of performing on-line maintenance, as long as this is done safely.
Sincerely,
'\\ wyA M
Dana A. Powers Chairmaa
References:
1.
Modified proposed Final Revision to 10 CFR 50.65, " Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," received May 5,1999.
2.
U. S. Nuclear Regulatory Commission, Revision 3 to Regulatory Guide 1.160 (DG-1082),
" Assessing and Mrinaging Risk Before Maintenance Activities at Nuclear Power Plants," April 1999.
3.
Report dated April 14,1999, from Dana A. Powers, Chairman, ACRS, to Shirley Ann Jackson, Chairman, NRC,
Subject:
Proposed Final Revision to 10 CFR 50.65, " Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants."
4.
U. S. Nuclear Regulatory Commission, Regulatory Guide 1.177, "An Approach for Plant-1 Specific, Risk. Informed Decisionmaking: Technical Specifications," August 1998.
5.
Letter dated December 14,1998, from Anthony R. Pietrangelo, Nuclear Energy Institute, to
- John C. Hoyle, Secretary of the Commission,
Subject:
Industry Comments on Proposed Rulemaking to 10 CFR 50.65(a)(3), Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants.
6.
Letter dated January 22,1999, from Ralph E. Beedle, Nuclear Energy Institute, to Shirley
' Ann Jackson, Chairman, NRC, regarding proposed revision to the maintenance rule and 10 CFR 50.59.
e
= -
-... _ - -.. ~...
.-......+
~~
'