ML20062B008
| ML20062B008 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf, Arkansas Nuclear, Waterford  |
| Issue date: | 10/05/1990 |
| From: | Muench G ENTERGY OPERATIONS, INC. |
| To: | Chilk S NRC OFFICE OF THE SECRETARY (SECY) |
| References | |
| RTR-NUREG-1407 GL-88-20, NUDOCS 9010230291 | |
| Download: ML20062B008 (5) | |
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Gerald W. Muench i
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L Mr.. Samuel J. Chilk Secretary of the Commission U. S. Nuclear Regulatory Commission Washington, D.C.
20555 Attention: Docketing and Service Branch g
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Subject:
Draft Generic Letter 88-20, Supplement 4, and Draft NUREG-1407, 55 Federal Register 30332
Dear Mr. Chilk:
Entergy Operations,.
ensra for Arkansas Nuclear One, Grand Gulf Nuclear L
Station and'Waterford w E'ectric Station, Unit 3, has reviewed the subject documents, and are pleasua tv provide the comments delineated in Attachment One.
L We have discussed with the Nuclect Management and Resources-Council (NUMARC) the proposed documents as well as evaluated the comments prepared by NUMARC on behalf [of the nuclear industry.
Entergy Operations endorses the comments provided by NUMARC on the subject documents.
We appreciate the opportunity to comment on.this matter.
Please contact me or
. Robert J. Murillo, (504) 595-2831, should there be any. questions concerning
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our comments.
i
. Sincerely,
/
l GWM/RJM/sep c
cc:
.S. D. Ebneter, NRC Region II, R. D. Martin, NRC Region IV, J. T. Chen, NRC-NRR, D. L. Wigginton, NRC-NRR, T. W. Alexion, NRC-NRR, C. Posluany, NRC-NRR, L. L. Kintner, NRC-NRR, NRC Resident Inspectors Office (W-3), NRC Resident Inspectors Office (GGNS), NRC Resident Inspectors Office (ANO)
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ATTACMMENT 1 ENTERGY OPERRTIONS COMMENTS ON DRAFT GENERIC LETTER 88-20 SUPP.4 i
AND NUREG-1407 l.
Pace 5.
Section 4.3 i
The final generic letter should state that the simplified fire risk evaluation method developed by NUMARC is acceptable or " enhancements" that are necessary to make it acceptable should-be identified.
s 2.
Pace 9.
Section 10 The requirement for identifying the methods and approach selected for performing the IPEEE requires that utilities make a determination of methods within 60 days of issuance of the supplement.
This is too short of a time frame to make this determination.
This time frame was reasonable for
.the original Generic Letter 88-20 because the options were well known and understood by the time a determination had to be made.- However, the external event options are not as well understood.nor have they been discussed and reviewed by the industry.
Furthermore, many utilities need to review the different methodologies for performing external events before deciding which method should be used at'their plant.
The utility staffs have been dedicated to addressing the original internal events IPE requirement and have not been able to spend the time to follow the development of the various methods as they were able to do for the internal
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events IPE.
Therefore, additional time should be allowed for the utility to make its determination of methods.
1 3.
Pace 9.
Section 10 f.
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The requirement for the submittal of the IPEEE results within three years is not sufficient time.
The limited 1
utility resources available to perform the IPE for internal events, external events, generic safety issues, utility L
specific applications, and accident management programs means that much of this work must be done in series and not in parallel.
Most utilities will have just submitted the results of their internal events IPE just one year prior to this date.
In many cases, the same individuals which worked on the internal events IPE will also be involved with the IPEEE.
The three year requirement will then only allow approximately one year to complete and report on the IPEEE.
This is insufficient.
The time frame allowed for the IPEEE should be consistent with and tied to that allowed for the internal events IPE, that is, three years from the submittal of the internal events IPE results.
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Pace 24. Section 4.2.2.
Item 2 The NRC proposes-that licensees write a summary of walkdown
" findings" with respect to the seismic review..The term
" findings" could be misconstrued to mean findings which are considered for reporting to the NRC, pursuant to $50.72 i
and $50.73 or $20.403.
The use of the term "results"'is suggested as an alternative.
5.
. Pace 25. Section 4.3 The'information submittal requirements for the seismic analysis varied according to the methodology chosen.
The information submittal requirements should be specified if a method other than a' fire PRA is chosen.
I 6.
Pace 25. Section 4.3 Item 5 Th'e requirement that documentation be provided, in each case where the plant-specific data used is less conservative than the data base used in the approved fire vulnerability methodologies, is a disincentive to use plant specific fire
' initiation data.
The IPEEE results will capture generic vulnerabilities instead of plant specific fire vulnerabilities by preferring generic. data.
There is no need for plant specific information to have more justification and discussion than generic data.
This requirements is contrary to the spirit of the Commission perspective "that systematic examinations are beneficial in identiffing plant-specific vulnerabilities to severe l
L accidents that could be fixed with low-cost improvements."
7.
Pace'25. Section 4 3.
Item 1 2
t After the licensee certifies that the IPEEE study reflects as-built conditions in the plant, as of a " design freeze"
-date or any other date for that matter, the NRC should not L
require a " status of. Appendix R modifications."
A status should be-requested only if the analysis indicates a potential vulnerability that is alleviated by crediting a planned Appendix R modification that has not yet been implemented.
8.
Pace 26. Section 4.4.
Item 3 l'
Maen a licensee chooses not to compare the plant to the SRP, there'is no need to list (Appendix 4, 4.4 #3, and NUREG-1407, 5.2.2) significant changes since OL (with respect to high winds floods, and other external events) in the IPEEE report.
This section requires licensees to report "significant changes" since OL regardless of which option a licensee' chooses (Figure 1 on page 13).
The requirements L
for providing updated information for significant changes L
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are adequately addressed in 50.71(e).
As a general matter, the-generic! letter should clearly state
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that the IPEEE analyses and.results are not part of the plant's licensing basis..Therefore, the generic letter should not require that updated information, either future plant changes or future changes to the IPEEE analyses, be provided to the NRC.
9.
Paae 26. Section 4.4.
Item 5 NUREG-1407 does not provide any guidance on the determination!of the associated conditional core damage frequency.. Guidance acceptable to the NRC should be identified and included either in the generic letter 4
supplement or NUREG-1407.
10.
Pace 30. Item "b"
For clarification, this item should be revised to state that licensees will " report to the NRC proposed modifications, if any, to correct identified vulnerabilities..." pursuant to procedures which implement 550.U9.
11.
NUREG-1407, once 3.
Section 2.4 This section-requests that licensees assess the effects of-applying new PMP criteria to their plants in terms of onsite flooding:and roof ponding.
However, no guidance is provided in this section or later as to acceptable methods to make this assessment.
Guidance should be added to the NUREG for this determination.
12.
NUREG-1407-Daae 4.
Section 2.6 Based on conclusion number 3, the phrase "or a scram" should be added to the last sentence of the last paragraph of this section.
13.
NUREG-1407. Daae 10. Section 3.2.5, last Daracraoh A peer review implies the use of external " experts in the professional field" for a review of the methodology chosen
't and its application.
This type of review would not necessarily. review the accuracy of design or as-built inputs to the analysis.
Assuming that-both the NRC and EPRI methods have been subjected to a peer review, it would be more appropriate for each plant to include an independent in-house review.to ensure the accurac'r of-the documentation packages (as required for internal evonts IPE) rather than for each plant to include a peer reviaw.
This assumes that both methodologies are relatively straight-forward and
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allows the utilities to. manage their resources to the best advantage rather than being required to spend resources on.
an effort which will not add substantially to the accuracy of the analysis.
14.
NUREG-1407. Section 4 Section 3 discusses requirements for containment performance assessments for seismic IPEEE, and Section 3.2 excludes additional containment performance assessments for high winds, floods and. transportation, and nearby ~ facility
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. accident IPEEE.
However,'Section 4 does not discuss the containment performance assessment for fire IPEEE.
This implies.that a containment performance assessment.is not required-for the. fire IPEEE.
The NUREG should explicitly state in Section 4.that a containment performance assessment L
is not required for fire IPEEE.
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