ML20127D665

Forwards Fax Sent to J Duncan of GE Providing Updated Punch List for Advanced BWR PRA Issues

ML20127D665
Person / Time
Site:	05200001
Issue date:	12/29/1992
From:	Kelly G Office of Nuclear Reactor Regulation
To:	Poslusny C Office of Nuclear Reactor Regulation
References
NUDOCS 9301150321
Download: ML20127D665 (14)

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. December 29.-1992 j NOTE'T0: Chet ' s us' .DARPNRR?

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FROM: Gle nel SPSB, DSSA, NRR

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SUBJECT:

UPDATED ABWR PRA PUNCH LIST TRANSMITTAL TO GE-I have enclosed a fax I sent to Jack Duncan, GE.that provides my updated punch list for the ABWR PRA issues.

Enclosure:

as stated O

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e The following chart is a summary of the-status of issues raised by the ' staff concerning the ABWR-PRA. This chart has been coordinated with GE to assure that it:is as accurate as possible in portraying issue status. The chart is current as of December 29, 1992.

An issue _is: judged " confirmatory" in the chart if GE has submitted (by fax, discussion, meeting handout, or letter) sufficient information for the staff to draw its conclusion regarding the issue. Most of the information submitted.

by GE has been provided in a preliminary-form.- All information must be translated by GE into_ SSAR modifications that capture _ issue resolution. ' A:few of the issues in the confirmatory list are being tracked there for completeness, although they were written.up as " resolved"-in the DFSER.

An issue is judged to be "open" in the chart if the staff is awaiting GE's response on staff- questions or if the staff still has the issue under review.  :

Note that I have provided some updated information from R.- Palla on back end analyses. It is possible that I may have misinterprated his intentions. Take his dates with a grain of salt. I think that most of the areas (back end)

- that I have marked-as having a FSER. input completion date of 2/26/93 could be moved to the " Confirmatory" list, but Bob is not here to confirm this. He will be back about January 7, 1993.

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. STATUS OFiABWR PRA ISSUES December 29. 1992

- ISSUE DESCRIPTION- STATUS ACTION CONFIRMATORY' ISSUES

1. RPS Reliability. 0-1-(Closed in DFSER)

2. GE to tipdate ECCS FT.-1A.- IB (Closed and other fault trees in DFSER)

3. GE to defend 10RV S-2--

frequency (Confi'rmatory Item 19.1.5.2-1)

4. GE to defend 10RV C-1 (Confirmatory success criteria Item 19.1.5.3-1)

5. GE to A fend one S-1-(Closed in-unplanned trip per year DFSER)

6. GE to evaluate 0-2 (0 pen Item support system. failures 19.2.1.5.2-1)  ;

as initiating events i

7. GE to confirm LOSP I-1(COLActionItem frequency and other 19.1.5.2-1)-

site-specific parameters

8. Confirm ATWS success C-2 (Closed in criteria DFSER)

9. Confirm RHR success 50-1 (Closed-in 4 criteria DFSER)

10. GE to justify CCF C-3 (0 pen. Item-data 19.' 1. 5. 4 - 1 ) -

11. GE to justify 0-5 (0 pen Item train-level CCF 19.1.5.4-1) approach is adequate

12. GE to justify test. C-4A (Confirmatory--

and maintenance data Item 19.1.5.5.2-1)~

analysis 13.-GE to perform CDF C-4B (Confirmatory- 1 sensitivity to outage Item 19.1.5.5.3-1) times and surveillance intervals

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14. GE to justify RHR, 0-6 (Closed in HPCF pump failure data DFSER)

15. GE to correct S-11 (Confirmatory credit taken for fire Item 19.1.5.4-1) water

16. GE to provide write 0-22a,0-22B(0 pen up on PRA as a design Item 19.1.2.2-1) tool

17. Staff questioned S-5 TO S-8, I-14 seismic capacity of the (Confirmatory Item following equipment: 19.1.6.3.2-1 and fuel assembly, flat- part of Open Items bottom tank, diesel 19.1.2.2.2-1 and generator, electrical 19.1.6.3.2-2) equ pment

18. Staff proposed use S-10 (Closed in of LLNL hazard curves DFSER)

19. GE to address SA-1 (Closed in hazard curve DFSER) uncertainties

20. GE to confirm I-10, 0-21B (0 pen seismic capacities of Item 19.1.2.2.2-1) equipment and incorporate into design specifications

21. GE to modify I-11 (Closed in seismic PRA to account DFSER) for soil structure failures

22. GE to commit COL I-12 (COL Action applicant to a specific Item 19.1.6.3.2-1) seismic walkdown technique

23. GE to correct the S-3 (Confirmatory treatment of firewater Item 19.1.5.4-1) in the Seismic Class II' CET

24. GE to link PRA IN-1 (0 pen Items

" requirements" and 19.1.2.2-1) insights to " Interface write up"

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-25. GE to submit:a fire-0-12 (0 pen Items PRA -19.1.2.2.2-2 and <

19.1.2.2.2-3).

26. Determine if CETs =0-138(0penItem.

need.to address 19.1.7.2-1)

- wetwell-drywell bypass ~?

27. Modify CETs for 0-17A,1-178(0 pen-

- severe accident Items 19.1.7.5-1, phenomena'. 19.1.7.5-2,-

19.1.7.6.1-1, 19.1.7.6.2-1, and' 19.1. 7. 6. 2 -2) -- ,

,- 28. Flashing during C-6 (0 pen-Item venting 19.1.8-1)'

29. Justify aspects of 0-14 (0 pen Item rupture disc set point 19.1.7.3-1)

30. Assess the. impact- 0-16B,0-18E._(0 pen-of CCI on source terms Items 19.1.7.5-1 and-19.1.8-1)

31. Uncertainty 0-18A -18B,'-18C

- Analysis (0 pen Items

- Identify risk 19.1.7.7-1, significant 19.1.7.3-1, and issues from 19.1.7.4-1) previous BWR studies-Screen-issues for applicability to ABWR

32. Rupture disc S-9(0penitem operation before 24 19.1.7.3-2).

- hours. ~

33. GE to provide 0-18A, 0-11 (0 pen level PRA uncertainty Item 19.1.5.11.1-1)

- analysis *

- 34. Credit for COPS- 5-4 (0 pen Item-19.1.7.3-1) i a

35. GE to provide PRA GE has provided_a insights discussion of balance of prevention and mitigation and a discussion of vulnerabilities.

36. GE to compare PRA 0-1B sequences from operating BWRs to the ABWR PRA sequences and identify why ABWR has lower CDF

37. RWCU as a high ACRS identified concerns SC-2 pressure DHR source with GE's design and assumptions. GE has agreed to "make the PRA come true." The staff is awaiting information on isolation signals that could isolate the entire RWCU. GE has submitted preliminary modifications to the RWCU to allow it to remove decay heat at high pressure. GE has RWCU-related COL action items to add to its SSAR.

ISSUES BELONGING 10 OJMRJAANCHES "J0. Assess the impact Structural calculations 0-16A. 0 1BE. (0 pen of CCI on containment under review by ECGB and item 19.1.7.5 2) integrity are not a PRA issue.

39. Devwell Head BA 1 (Bagchi)

Ultimate Strength

40. Service Level C for BA-2(Bagchi)

Containment

41. Consequence CA 3 (Confirmatory Analysis item 19.1.9 1)

42. EPZ Consequence CA-4 Analysis

43. Consequence CA-1 Analysis and Site Acceptability -

Appendix 2A

35. Treatment of ATWS 5-12 as a late containment failure in CET analysis

37. Drywell Sump (SCSB issue) BA-3 penetration by corium

4 LS$11EJISCRlPTlqN STAIUS ACTION DEEN ISSUES

1. GE needs to take its Staff expects GE to provide GE's action to informal submittals and majority of its $$AR submit followed by write them up in the updates on PRA issues in the staff's review SSAR. December 1992, of these submittals.

(GE to submit by 12/31/92)

2. CE is to analyze GE's previous submittals on GE submited LOCAs outside of these LOCAs were not reanalysis on 11 containment (0-4) acceptable to the staff or and a supression/5 the ACRS. pool bypass analysis on 12/17/92. Staff is reviewing and ,

will complete its review by January 20, 1993. 0-4B

3. GE is to list Outstanding questions GE submittal on assumptions / reliability include listing of systems 12/14/92. Staff to values for systems that important to safety but not complete review by are not part of the modeled in PRA: Systems 1/15/93. 0-21 A certified design, but modeled in PRA but not part are modeled in the PRA of Design certification (e.g., UHS and Reactor Service Water Pump House):

Awaiting reliability assumptions for those systems modeled in PRA.

4. GE to requantify PRA GE has submitted its GE to submit by based on an up-to date updated requantification. 12/29/92. PRA-1A plant model There are a series of questions outstanding related to this submittal.

5. GE to provide GE has not proviced seismic GE to submit. (GE seismic capacities of capacity figures for the to submit by systems not.in the Reactor Service Water Pump 12/31/92) certified design House.

6. Uncertainty Analysis GE to provide data on GE submittal on

- Treatment of wetwell- applicability of vacuum support vacuum drywell bypass in CET breaker operating breaker leak test experience data to ABWR data received on (10/27/92). GE provided 12/10/92. Staff to ordering of top events in complete FSER input CET on 11/3. on 2/26/93. 0-18G

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7. Severe Accident The significance of steam GE submittal on Closure explosions in ABWR is potential for reduced by having a dry flooded cavity at cavity at the time of vessel failure and vessel failure. Additional chronology for information on the additional cases frequency of a flooded reported in S$AR cavity was requested during provided 12/10/92.

10/1/92 meeting to support Staff to complete closure of this issue. FSER input by 2/26/92. NRC-1

8. Accident management Staff evaluation provided GE submittal on to GE in draft Severe additional guidance Accident Closure chapter. for COL applicant on GE's planned response accident management discussed 10/5/92. plan received on 12/14/92 as new section 19.9.14.

Staff to complete FSER input by 2/26/93. NRC-2

9. SAMDA submittal Revised SAMDA analysis GE to modify submitted 6/30/92 and submittal to address discussed with GE 10/8/92. concerns discussed during 10/8/92 meeting. (GE to submit by 12/18/92)

HRC-3

10. Containment GE has proposed to address GE to reevaluate isolation failure this issue by extending- seismic issue after during seismic event analysis of LOCAs outside completing analysis containment (19E.2.3.3) to of issue for seismically-initiated internal events. (GE events. The approach for to submit by analysis of LOCAs outside 12/31/92) (0-4. 0-containment (for internal 19) If all HCLPF events) was subsequently sequence values rejected by staff and is 0.69, Ge need not now being addressed as perform any further issue 0-4. analysis for containment and item will become confirmatory.

11. AC Power Recovery GE submitted reassessment of 0.6 value assumed for probability of recovering AC power on 11/3/92. Staff to com)1ete FSER input )y 2/26/93.

12. GE to provide decay The staff has sent GE a (GE submitted on heat removal list of formal questions. 12/18/92) Staff to reliability study complete review by 2/26/93. 0-20

13. GE to provide The staff is awaiting a (GE submitted on internal flooding subcompartment analysis of 12/18/92) Staff to analysis the effect of high pressure complete review by pipe breaks on the walls 2/26/93. 1-9 between divisions.

Analysis expected from GE in mid-December.

14. Human factors in GE made related submittals GE to provide PRA (C-5. 0-7 thru 0- on sensitivity of CDF to response. (GEto 10, 1-2 thru l-7) human error (10/16/92 and submit by 12/18/92) 6/1/92), identification of C-6 to I-7 To be human errors in Level 1. provided in new Level 2, and seismic 19D.7.

analyses (6/25/92), and PRA data uncertainty analysis-(6/18/92). Staff requested additional information on 10/27/92.

15. GE to provide PRA- The staff has discussed The staff has based seismic margins with GE its concerns with transmitted guidance

-analysis the ABWR seismic margins on performing a PRA-submittal and has based margins transmitted questions to analysis for GE. GE has responded by evolutionary fax and meeting handouts to designs. (GE to many of these questions, submit by 12/23/92, but not received as of 12/29/92), SA-2

16. GE to provide PRA- GE has submitted its The staff has based input to ITAAC version of PRA based ITAAC transmitted its insights. coments to GE on GE's ITAAC submittal based on PRA insights. GE has not provided a completion date for ITAAC. GE and the staff are still discussing the particulars of PRA-based ITAAC. PRA-3

17. Site specific The staff's draft SECY The staff's action design verification: paper on Design is to modify the external floods, certification and Licensing siting criteria for transportation hazards Policy issues Pertaining to the ABWR since no Passive and Evolutionary site-specific Advanced Light Water external flooding Reactor Designs states that analysis has been 10 CFR 52.47 requires the provided. The analysis of both internal siting criteria will and external events. At exclude sites where the Design Certification it would be possible stage, site-specific events for external floods such as tornadoes and to exceed the height extreme wind may be of the site grade enveloped using bounding level and where analyses to show that the other non-enveloped events are insignificant, external events are In performing the COL a threat. GE review, the staff will believes that it review the site-specific need not take any characteristics to ensure action and seeks that events enveloped by staff confirmation, the bounding analyses have The staff is been properly addressed, awaiting Commission action on staff recommendations. I-8

18. Not risk impact of GE confirmed passive flooder system (11/3/92) alloy mixtures to be used in passive flooder valve. The staff will complete its FSER input by 2/R6/93. 0-15 i

19. Backend Uncertainty The staff will Analysis - Perform complete its FSER sensitivity analyses input by 2/26/93.

for issues of potential 0 180 risk significance to ABWR

20. Uncertainty Staff to work with Analysis - Treatment of BNL contractors to CCI coolability in CET address risk significance of issue in FSER. Staff to com)1ete its FSER-input >y 2/26

-(0-18E,0-16)/93.

21. Uncertainty GE to provide .

Analysis - Treatment of justification that.

direct containment reactor heating _in CET depressurization system is highly reliable during seismic events (CEB92-41-2). GE submittal on 11/3/92 only partly addressed this. GE still has to address-reliabiltiy/

vulnerability of ADS function in seismic.

Also has to address wetwell spray availability and.:

containment response. -(GE to submit by 12/31/92)

Based on 10/1/92 meeting, staff to review information

.provided in 19E.2.1.2.2 re -

ability to

'depressurize Class 18 sequences.- Staff to-document evaluation in FSER.

0-180

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m m_-- _ ,-_ - - _ - - - _ _ - _ _ - - - - _ - - - - _ - _ _ - - _ - - _ - - - - _ _ _ - _ _ _ - - _ - - _ _ _ _ - - _ - - - - - - - - - - - . - -

27. L osequence related aQrtificantdifferences Staff to work with issues (CA-1.2,3) obseived between BNL and GE BNL contractors to conseg sence calculations reflect differences for ap)arently similar between codes in source ',erms were noted FSER. Staff work to during ;0/1/92 mooting, be completed by Based oh follow up 2/26/93. Staff discurs'on on 10/28/92 believes that no differe' ices appear to be further action due to itse of MACCS versus required by GE.

CRAC2.

23. GE is to analyze The Reacter Systems Branch SRXB. 0-3 interfacing LOCAs is not satisfied with the resolution proposed by GE for its upgrading of low pressure system piping.

This issue will remain open until GE/ staff agree on upgrado criteria and the staff PRA people can review it to determine if the resolution has any negative effect on its conclusions.

GE has submitted its proposed resolution to this issue.

24. GE to use PRA GE submitted its revised GE submitted revised insights to suggest RAP input on November 11. Appendix K I?/92, areas to be added to 1992. Rest of revision due Staff review to be the ABWR reliability 12/4/92. complete by 1/30/93.

assurance program I-15 w

The followina are SCSB or other branch issues

28. Fuel-Coolant Staff pursuing independent SPSB finds for the Interaction analysis of FC explosion. purposes of the ABWR PRA review that GE has provided sufficient information in this area.

29. Core Debris MACE IB had heat fluxes GE has indicated coolability/ Core greater than 100 kW/m' for that it has provided concrete Interaction first nine hours. Staff SC5B with additional ex1auating less than that information for upper heat flux. Staff justifying min heat evaluating sump design. flux of 100kw/m' for Pedestal structural the reactor case.

integrity under discussion. GE believes all of its actions are complete. From SPSB's perspective, this is true.

30. Containment Bypass Severe accidents demonstrated .6ft' with fire water. 0. l f t' demonstrated w/o fire water. GE to document further information on DBA analysis.

31. Compliance with EPZ Emergency Plan Criteria and Methodology

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