ML20203L982
| ML20203L982 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 02/19/1998 |
| From: | Joseph Sebrosky NRC (Affiliation Not Assigned) |
| To: | NRC (Affiliation Not Assigned) |
| References | |
| NUDOCS 9803060344 | |
| Download: ML20203L982 (4) | |
Text
February 19, 1998' APPLICANT: Westinghouse Electric Company PROJECT:
AP600
SUBJECT:
DOCUMENTATION OF AP600 INFORMAL CORRESPONDENCE TO WESTINGHOUSE CONCERNING FINAL SAFETY EVALUATION REPORT (FSER) OPEN ITEMS FOR THE LEVEL 2 PROBABILISTIC RISK ASSESSMENT (PRA)
On February 18,1998, the staff provided Westinghouse with the issues in Attachment 1.
The purpose of the transmittal was to provide Westinghouse with an updated list of issues that '
1 Westinghoase needed to address prior to issuance of the FSER for the level 2 PRA.
original signed by:
Joseph M. Sebrosky, Project Manager Standard stion Project Directorate Division of Reactor Program Management l
Office of Nuclear Reactor Regulation Docket No. 52 003
- Attachments: As stated cc w/atts: See next page DISTRIBUTION w/ attachments:
' Docket FW
' PD3T R/F TKenyon PUBLIC BHuffman JSebrosky DScaletti JNWilson
, SMagruder JHWilson MDunsaniwskyj f
DISTRIBUTION w/o attachments:
SCo; lins /FMiraglia,0-12 G18 BSheron,0-12 G18 BBoger,0-12 G18 m
3 R3 JRoe DMatthews -
TQuay s'
l ACRS (11) _ _
_ JMoore,015 B18 RPalla,0-8 H7 -
MSnoddarly,0-8 H7 sMonninger,0-8 H7 DOCUMENT NAME: A:\\ FAX PRA2. SUM
" To re1:eive a copy of this document, Indicate in the box: "C" = Copy without attachment / enclosure "E" = Copy with attachment / enclosure "N" = No copy OFFICE PM:PDST:DRPM -l SCSB:DSSA _ l D:PDST:DRPM l -
l l
NAME JMSebrosky:sg kn RPalla W TRQuay -ftV DATE-02/dl98 1/
02/1998 02/I9/98 i
OFFICIAL RECORD COPY P P'IG T* P'T'T pgg$y
.mo 9803060344 990219 SUd O63 4 2 6 2 eu 5 PDR ADOCK 05200003 E
pog u
y.
Westinghouse Electric Corporation Docket Nc,52-003 cc:
Mr. Nicholas J. Liparulo, Manager _
Mr. Frank A. Ross Nuclear Defety and Regulatory Analysis U.S. Department of Energy, NE-42 Nuclear and Advanced Technology Division Office of LWR Safety and Technology Westinghouse Electric Corporation 19901 Germantown Road-P.O. Box 355 s
Germantown, MD 20874 Pittsburgh, PA 15230 Mr. Russ Bell Mr. B.- A. McIntyre Senior Project Manager, Programs Advanced Plant Safety & Licensing Nuclear Energy institute Westinghouse Electric Corporation 1776 i Street, NW Energy Systems Business Unit Suite 300 Dox 355 -
Washington, DC 20006-3706 Pittsburgh, PA 15230 '
Ms. Lynn Connor Ms. Cindy L. Haag Doc-Search Associates Advanced Plant Safety & Licensing Post Office Box 34 Westinghouse Electric Corporation
~ Cabin John, MD 20818 Energy Systems Business Unit Box 355 Dr. Craig D. Sawyer, Manager l
Pittsburgh, PA 15230 Advanced Reactor Programs GE Nuclear Energy Mr, M. D. Beaumont 175 Curtner Avenue, MC-754 Nuclear and Advanced Technology Division.
San Jose, CA 95125 Westinghouse Electric Corporation One Montrose Metro.
Mr. Robert H. Buchholz 11921 Rockville Pike GE Nuclear Energy
. Suite 350 -
175 Curtner Avenue, MC-781 Rockville, MD 20852 San Jose, CA 95125 ~
f Mr. Sterling Franks Barton Z. Cowan, Esq.
U.S. Department of Energy-Eckert Seamans Cherin & Mellott NE-50 600 Grant Street 42nd Floor 19901 Germantown Road Pittsburgh, PA 15219 Germantown, MD 20874 Mr. Ed Rodwell, Manager Mr. Charles Thompson, Nuclear Engineer PWR Design Certification AP600 Certification Electric Power Research Institute NE-50 3412 Hillview Avenue
- 19901 Germantown Road Palo Alto, CA 94303 Germantown, MD 20874 Mr. Robert Maiers, P.E.
Pennsylvania Department of -
Environmental Protection Bureau of Radiation Protection Rachel Carson State Office Building P.O. Box 8469 HarrisburD, PA 17105-8469
Cmments Sent to Westinghouse on February 18,1998, Regarding the Level 2 PRA lasues for Level 2 PRA 2/18/98 Everything in the SER is closed out, but the following is still needed from WEC before issuance:
s 1.
Add ATWS RAI response to PRA 2.
Add response to RAI 720.460F to PRA (new) 3.
Provide the commitment (tech spec basis?) that temporary closures will have a pressure capability of at least containment design pressure. Note - J. Monninger indicated that WEC agreed to this. They may have already responded on this but I haven't seen it.
4.
Provide a description of the dominant contributors /causes for failure of reactor cavity flooding in the shutdown PRA. Bob Palla spoke with J. Freeland at WEC about this on February 12,1998, and J. Freeland indicated that he would check into this and provide a response by today, it may be necessary to modify the shutdown report and PRA to include this information.
Based on the truncated call with Jim Freeland and Bob Palla on February 17,1998, the following WEC actions will resolve the level 2 shutdown issues:
a) Correct the description re: contributors to LRF for the focussed shutdown PRA reported 1
in PRA Section 548.3.3 (should be ~80 percent from failure of cavity flooding) l b) Correct and supplement the description of dominant contributors /causes of failure of reactor cavity flooding in section 6.1 (item j) of shutdown evaluation report WCAP-14837, Revision 2 (should be CCF of strainers, I&C, etc, rather than " valving off many of the water sources to containment")
c) Call out the following as insights from the shutdown study-(1) The major contribution to LRF is from failure to flood cavity due to CCF of strainers. IRWST strainer plugging will be controlled by inclusion in D-RAP, and by a tech spec requiring that the screen are not restricted by debris. (This same statement is made in our FSER for the at power PRA but was not included in Section 19.1.8. A statement that covers both the at-power and the shutdown situations is preferred.)
(2)
Failure to close containment hatches, air locks, and spare penetrations which are initially open is considered highly unlikely in the AP600 design due to operating restrictions and design features, specifically, a tech spec which will not permit such penetrations to be open during shutdown unless the penetrations can be closed prior to steaming into conta!nment, and the equipment hatches are provided with a self-contained power source for closing the hatch during a station blackout event. The disposition is Tech 3pecification 3.6.8 and SSAR Section 3.8.2.1.4.
l 1
o
e.
o i
2-5.
Modify the level 2 insight (number 41) and ITAAC regarding embedded piping in the concrete basemat. The concem here is twofold -i.e. there is no embedded piping that can provide a pathway (1) into the sump (already included by WEC), and (2) from the sump to the outside of containment (not presenth/ included by WEC) R. Lutz (WEC) and I discussed and agreed on this last Thurday, but he didn't write the insight. The appropriate person at WEC needs to make the modification.
6.
Provide the SSAR cnd ITAAC chan0es re: RPV insulation as agreed with WEC (M. Corletti) during last meeting.
7.
Provide the modifications to ERGS to addrer,s actuation of cavity flooding and hydrogen ignitors, as agreed with WEC (M. Corietti) during Februasy 9,1998, telecon.
8.
Reconcile the containment isolation valve tables in PRA Cl; apter 24 and SSAR Chapter 6.
Confirm any differences between the tables had no impact cn the results of the screening analysis found in the PRA.
>