ML20140G131
| ML20140G131 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 06/03/1997 |
| From: | Joseph Sebrosky NRC (Affiliation Not Assigned) |
| To: | Liparulo N WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| References | |
| NUDOCS 9706130370 | |
| Download: ML20140G131 (4) | |
Text
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WASHINGTON, D.C. 20665 4001 o,
June 3,1997 2~3 Mr. Nicholas J. Liparulo, Manager i
Nuclear Safety and Regulatory Analysis Nuclear and Advanced Technology Division Westinghouse Electric Corporation i
P.O. Box 355 Pittsburgh, PA 15230
SUBJECT:
FOLLOWON QUESTIONS REGARDING THE EX-VESSEL SEVERE ACCIDENT ANALYSIS FOUND IN THE PROBABILISTIC RISK ASSESSMENT (PRA) FOR THE AP600
Dear Mr. Liparulo:
As a result of its review of the June 1992 application for design certifica-tion of the AP600, the staff has determined that it needs additional informa-tion. Specifically, the enclosure to this letter contains requests for additional information concerning ex-vessel severe accident analysis found in the AP600 PRA.
You have requested that portions of the information submitted in the June 1992, application for design certification be exempt from mandatory public disclosure. While the staff has not completed its review of your request in accordance with the requirements of 10 CFR 2.790, that portion of i
the submitted information is being withheld from public disclosure pending the i
staff's final determination. The staff concludes that these followon ques-tions do not contain those portions of the information for which exemption is sought. However, the staff will withhold this letter from public disclosure for 30 calendar days from the date of this letter to allow Westinghouse the opportunity to verify the staff's conclusions.
If, after that time, you do not request that all or portions of the information in the enclosures be withheld from public disclosure in accordance with 10 CFR 2.790, this letter will be placed in the Nuclear Regulatory Commission Public Document Room.
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$au-9706130370 970603 PDR ADOCK 05200003 A
Mr. Nicholas J. Liparulo June 3, 1997 i
If you have any questions regarding this matter, you may contact me at (301) 415-1132.
4 Sincerely, I
original signed by:
Joseph M. Sebrosky, Project Manager j
Standardization Project Directorate Division of Reactor Program Management Office of Nuclear Reactor Regulation 4
j Docket No.52-003
Enclosure:
As stated i
cc w/ enclosure:
See next page l
DISTRIBUTION:
- Enclosure to be held for 30 days 1* Docket File '
PDST R/F TMartin
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TKenyon BHuffman JSebrosky 4
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MSnodderly, 0-8 H7 SBasu, T-10 K8 CTinkler, T-10 K8 1
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DOCUMENT NAME: A: EXVSL.RAI Ta seeelve a copy of this document,Indcate in the box: "C" = Copy without ettechment/ enclosure "f* = Copy with ettechment/ enclosure
'N' = No copy 0FFICE PM:PDST:DRPM SCSB:DSSA E RES:AEB:(ST D:PDST:DRPM l NAME JSebrosky:sgJnT JKudrick/#$4,# SBasu V
TQuay -0 4 DATE 06/ t/97
//
06/2 /97 06/v/97 06/ 3 /97 OFFICIAL RECORD COPY
Mr. Nicholas J. Liparulo Docket No.52-003 Westinghouse Electric Corporation AP600 cc: Mr. B. A. McIntyre Ms. Cindy L. Haag Advanced Plant Safety & Licensing Advanced Plant Safety & Licensing Westinghouse Electric Corporation Westinghouse Electric Corporation Energy Systems Business Unit Energy Systems Business Unit P.O. Box 355 Box 355 Pittsburgh, PA 15230 Pittsburgh, PA 15230 Mr. M. D. Beaumont Mr. S. M. Modro Nuclear and Advanced Technology Division Nuclear Systems Analysis Technologies Westinghouse Electric Corporation Lockheed Idaho Technologies Company One Montrose Metro Post Office Box 1625 11921 Rockville Pike Idaho falls, ID 83415 Suite 350 Rockville, MD 20852 Enclosure to be distributed to the following addressees after the result of the proprietary evaluation is received from Westinghouse:
Mr. Ronald Simard, Director Ms. Lynn Connor Advanced Reactor Programs DOC-Search Associates Nuclear Energy Institute Post Office Box 34 1776 Eye Street, N.W.
Cabin John, MD 20818 Suite 300 Washington, DC 20006-3706 Mr. Robert H. Buchholz GE Nuclear Energy Mr. James E. Quinn, Projects Manager 175 Curtner Avenue, MC-781 LMR and SBWR Programs San Jose, CA 95125 GE Nuclear Energy 175 Curtner Avenue, M/C 165 Mr. Sterling Franks San Jose, CA 95125 U.S. Department of Energy NE-50 Barton Z. Cowan, Esq.
19901 Germantown Road Eckert Seamans Cherin & Mellott Germantown, MD 20874 600 Grant Street 42nd Floor Pittsburgh, PA 15219 Mr. Charles Thompson, Nuclear Engineer AP600 Certification Mr. Frank A. Ross NE-50 U.S. Department of Energy, NE-42 19901 Germantown Road Office of LWR Safety and Technology Germantown, MD 20874 19901 Germantown Road Germantown, MD 20874 Mr. Ed Rodwell, Manager PWR Design Certification Electric Power Research Institute 3412 Hillview Avenue Palo Alto, CA 94303
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AP600 PRA REVIEW REQUEST FOR ADDITIONAL INFORMATION REGARDING DETERMINISTIC CALCULATIONS OF EX-VESSEL PHENOMENA a
j 720.407 The Westinghouse submittal dated April 21, 1997, (NSD-NRC-97-5078) contains calculations and results for one vessel failure mode, i.e., localized small failure (.06 m diameter hole at the transi-tion between the hemisphere and the cylinder) leading to a drip-4 ping flow of metallic melt at 3.8 m/s. What is basis for a.06 m i
diameter hole? Also, pool depth at vessel failure is taken to be 3.89 m (see Table B-1 on page B-15 of an earlier submittal dated
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December 12,1996).
Is the lower head submerged in this case?
Finally, what are the coolant temperature and the system pressure for this case?
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720.408 The second vessel failure mode, i.e., hinged failure leading to a very high flow rate is considered in the earlier submittal dated'
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December _12, 1996, but no calculations are provided in the f
April 21, 1997 submittal.
Please provide the calculations for the hinged failure mode, or justification for not providing the calculations.
720.409 In Table B-3 on page B-17 of the December 12, 1996, submittal the melt temperature and superheat for the hinged failure mode are shown to be 1890 K and 80 K, respectively.
The melt is predomi-nantly oxidic, at least, it.is supposed to be. Therefore, melt l
temperature and superheat quoted do not appear to be correct.
720.410 For the dripping flow case, only the pressure trace (in the pool) l is provided in the April 21, 1997, submittal. Westinghouse states in the letter that they do not have the code capability of plot-ting from the TEXAS code, and supplied the information in a tabular form.
Please provide an electronic version of the table that is included in the April 21, 1997, submittal.
In addition, please provide plots vs time for cavity wall pressure, and impulse load. (If the latter data will be provided in a tabular form, also provide an electronic version.)
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Enclosure i
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