ML20137N266
| ML20137N266 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 04/01/1997 |
| From: | Krieger R SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9704080312 | |
| Download: ML20137N266 (7) | |
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L April 1,1997 U. S. Nuclear Regulatory Commission i;
- Document Control Desk i
Washington, D.C. 20555 3
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. Subject.
Docket Nos. 50-361 and 50-362 Reply to a Notice of Violation i
San Onofre Nuclear Generating Station, Units 2 and 3
References:
(1)
Letter from Mr. J. E. Dyer (NRC) to Mr. Harold B. Ray (SCE),' dated March 3,1997 (Notice of Violation,.NRC Special inspection Report 50-361/362 96-14) 4 (2)
Letter from Mr. T. P. Gwynn (NRC) to Mr. Harold B. Ray (SCE),
dated December 6,1996 (NRC Inspection Report 50-361/362 i
96-14) l (3)
Letter from Mr. Dwight E. Nunn (SCE) to Mr. S. J. Collins, dated January 8,1997 (Request for Additional lofom1ation - Maintenance L
Rule implementation San Onofre Nuclear Generating Station, Units t
2 and 3)
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(4)
Letter from Mr. G. T. Gibson (SCE) to Mr. K E. Brockman (NRC),
dated October 31,1996 (San Onofre Nuclear Generating Station's Response to NRC Inspectors Follow-up on Unresolved item (50-361 (362)/96009-03))
Reference 1 transmitted a Notice of Violation resulting from NRC Inspection Report (IR)
No. 50-361/362-96-14 (Reference 2), conducted by Messrs. C. J. Paulk and J. E.
Wittemore on October 20 through November 15,1996, at the San Onofre Nuclear Generating Station, Units 2 and 3. The Notice of Violation contains two cited violations (9614-02 and 04). The violations involve: (1) a failure to have adequate smoke
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- exhaust damper performance criteria; and (2) a failure to have adequate performance #
criteria to. monitor reliability for risk significant structures, systems, and components
- (SSC).
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In accordance with Reference 1, the Enclosure to this letter provides Edison's reply to the Notice of Violation.
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The Reference 1 cover letter states, "In addition, you should address what corrective -
. actions you have taken to enhance management controls over, and awareness of,
' implementation of your Maintenance Rule program in response to your self-evaluation
- findings." The self evaluation conducted by San Onofre identified weaknesses in the Maintenance Rule project's management and oversight in monitoring associated activities and schedules.
To addrest ihe project management concems, an inter-divisional middle management team was established to review the existing Maintenance Rule program and identify enhancements to the program. This team (Maintenance Rule implementation Team) is continuing to identify and implement program enhancements based on industry experience.z To enhance management oversight of the Maintenance Rule, a steering committee of division managers was established. This committee provides guidance to and reviews program policies developed by the implementation team.
If you have any questions, please contact me.
Sincerely r
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Enclosure j.
l cc:
E. W. Merschoff, Regional Administrator, NRC Region IV A. T. Howell lli, Director, Division of Reactor Safety, NRC Region IV K. E. Perkins Jr., Director, Walnut Creek Field Office, NRC Region IV
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J. A. Sloan, NRC Senior Resident inspector, San Onofre Units 2 & 3 l
M. B. Fields, NRC Project Manager, San Onofre Units 2 & 3 i
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ENCLOSURE V;OLATION A
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4 The enclosure to Mr. J. E. Dyer's letter dated March 3,1997, states, in part:
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t "10 CFR 50.65(a)(1) states, in part, that each holder of an operating license.... shall monitor the performance or condition of structures, systems, or components (SSCs) 4 against licensee-established goals... and that such goals shall be established i
commensurate with safety.
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"10 CFR 50.65(a)(2) states, in part, that monitoring under (a)(1) is not required where it -
f has been demonstrated that the performance or condition of an SSC is being effectively controlled through the performance of appropriate preventive maintenance such that the SSC remains capable of performing its intended function. Paragraph (c) states that l
. '[t]he requirements of this section shall be implemented by each licensee no later than July 10,1996.'
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" San Onofre Nuclear Generating Station Procedure S0123-XIV-5.3, ' Maintenance Rule Program implementation,' Revision 0, Temporary Change Notice 0-3, Section 6.3.3, implements, in part, the requirements of (a)(2) above. Section 6.3.3 states, in part, that for nonrisk-significant SSCs the plant level performance criteria will be unplanned automatic reactor scrams, unplanned capability loss factor, unplanned safety system actuation, unplanned shutdown safety functional events, abnormal radiological releases, and core damage frequency.
" Contrary to the above, since September 20,1996, the licensee failed to adequately i
monitor the performance of the Common Control Room Complex Smoke Exhaust Dampers in that none of the performance criteria designated in Procedure SO123-XIV-5.3 were adequate to demonstrate that the dampers' performance was effectively controlled through appropriate preventive maintenance. (01014)
"This is a Severity Level IV violation (Supplement 1). (50-361/9614-02; 50-362/9614-02)"
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RESPONSE TO VIOLATION A
- 1. Reason for the Violation As noted in References 3 and 4, the Smoke Dampers were initially scoped within the
- Control Room HVAC Emergency System. The Control Room HVAC Emergency
- System was identified as risk significant based on Expert Panel judgment. However, after a more detailed review, the Expert Panel concluded the smoke dampers did not q
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= support functions for which the Control Room HVAC Emergency System was judged l
risk significant. Consequently, the smoke dampers were reclassified as non-risk significant. As such, they were to be monitored under plant level performance criteria.
l The reason for the violation was Edison believed the smoke dampers did not require j
any specific performance criteria because they were non-risk significant. In
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I Reference 3, Edison agreed that the use of plant level performance criteria (i.e.,
unplanned automatic reactor scrams, unplanned capability loss factor, unplanned safety system actuation, unplanned shutdown safety functional events, abnormal radiological releases, and core damage frequency) was not sufficient to ensure the smoke damper's function would be maintained.
j 2.- Corrective Actions Taken and Results Achieved j
i As noted in Reference 3, Edison has taken corrective action to revise the preventive i
S' maintenance program for the smoke dampers. As these are newly initiated activities, the corrective action effectiveness can not yet be assessed.
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- 3. Corrective Actions That Will Be Taken to Avoid Further Violations 5
As committed to in Reference 3, Edison agreed to develop specific criteria for the smoke dampers. In addition, Edison agreed to reexamine our use of plant-level 4
performanco criteria. This review will confirm that non-risk significant functions provided by SSCs within the maintenance rule scope are monitored by appropriate plant level or specific performance criteria.
- 4. Date When Full Compliance Will be Achieved As noted in Reference 3, Edison will be prepared to discuss the smoke damper criteria, and the results of our reexamination of the use of plant-level performance criteria, j
during the NRC Maintenance Rule baseline inspection currently scheduled for July 28, i
1997.
VIOLATION B '
Th6 enclosure to Mr. J. E. Dyer's letter dated March 3,1997, states, in part:
10 CFR 50.65(a) (1) states, in part, that each holder of an operating license... shall monitor the performance or condition of SSCs against licensee-established goals...
and that such goals shall be established commensurate with safety.
"10 CFR 50.65(a)(2) states,'in part, that monitoring under (a)(1) is not required where it has been demonstrated that the performance or condition of a SSC is being effectively -
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Enclosure
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j controlled through the performance 1 appropriate preventive maintenance such that -
l the SSC remains capable of performnig its intended safety function. Paragraph (c)
- states that '[t]he requirements of this section shall be implemented by each licensee m
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- later than July 10,1996.'
" Regulatory Guide 1.160, ' Monitoring the Effectiveness of Maintenance at. Nuclear
. Power Plants,' Revision 1, endorses NUMARC_93-01, ' Industry Guidelines for
' Monitoring the Effectiveness of Maintenance at Nuclear Power Plants,' Revision 0, as j
an acceptable method for implementing the requirements of 10 CFR 50.65. Regulatory J
- Guide 1.160 states that the methods described in the guide will be used in the evaluation of the effectiveness of maintenance activities of licensees who are required j
to comply with 10 CFR 50.65 unless a licensee has proposed an acceptable alternative 1
. method of compliance.
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"NUMARC 93-01, Section 9.3.2, states, in part, that performance criteria for evaluating l
~ SSCs are necessary to identify the standard against which performance is to be measured. Criteria are established to provide a basis for determining satisfactory i
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performance... (for SSCs monitored under (a)(2)). Additionally, Section 9.3.2 states that performance criteria for risk significant SSCs be established to assure that reliability and availability assumptions used in the plant specific probabilistic risk assessment, individual plant examination, or other risk detarmining analysis are 4
maintained or adjusted when necessary.
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" Contrary to 10 CFR 50.65(a)(2), as of October 22,1996, the licensee, in choosing the NUMARC approach, failed to demonstrate that the performance or condition of SSCs i
U was effectively controlled through the performance of appropriate preventive maintenance in that the licensee did not demonstrate that the performance criteria used l
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to monitor reliability would ensure that the SSCs remained capable of performing their i
i intended safety function. Specifically, in accordance with NUMARC 93-01, for those risk significant SSCs within the scope of 10 CFR 50.65, the licensee established performance criteria to monitor reliability that neither considered, nor were bounded by, the safety significance defined by the licensee's plant-specific probabilistic risk assessment, individual plant examination, or other risk determining analysis for those
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SSCs.' The licensee had not proposed an acceptable alternative to demonstrate compliance with 10 CFR 50.65(a)(2). (02014) l
'This is a Severity Level IV violation (Supplement 1).
(50-361/9614-04;50-362/9614-04)"
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Enclosure RESPONSE TO VIOLATION B
- 1. Reason for the Violation As noted in References 3 and 4, the Maintenance Rule is La nrst performance-based rule and, as a result, acceptable methods to achieve compliance with the rule were not completely understood between the industry and the NRC. Edison believed it implemented the rule in accordance with industry guidance acceptable to the NRC.
Edison notes, as evidenced by similar violations at other facilities, the misunderstanding of NRC expectations was generally industry-wide. Edison notes these expectations were not cielineated in either 10 CFR 50.65 or Regulatory Guide 1.160, ? Monitoring the Effectiveness of Maintenance at Nuclear Power Plants."
Therefore, the reason for the violation was misunderstanding of NRC expectations.
- 2. Corrective Actions Taken ano Results Achieved A review of recent NRC and industry guidance on the subject was performed. As a result, an understanding was gained of the NRC expectations regarding the linking of reliability performance criteria to the PRA/IPEllPEEE. Edison now understands a more exact correlation between reliability performance criteria and the PRA is expected.
in order to determine reliability performance criteria commensurate with safety, a plan has been developed to determine the link between countira functional failures and the reliability a ssumptions used in the PRA for risk significant SSCs at San Onofre. This requirer dotermining the ratio of allowed functional failures to an estiinated number of demands and operating hours during a given time period. For those risk significant SSCs having reliability performance criteria not bounded by the PRA,' a calculation will be performed to demonstrate that use of the selected reliability performance criteria results in insignificant increases in risk.
- 3. Corrective Actions That Will Be Taken to Avoid Further Violations Edison continues to maintain initiativea to better understand the NRC's expectations for maintenance rule compliance, including:
attending or monitoring industry meetings (NEl and NRC);
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active networking with industry peers; and o
mcnitoring results of the maintenance rule baseline inspections.
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Enclosure l
- 4. Date When Full Compliance Will be Achieved i
The linking of the reliability performance criteria to the PRNIPE/IEEE, and associated i
procedure changes, are anticipated to be completed by the NRC baseline inspection at
. San Onofre currently scheduled to begin July 28,1997.
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