ML20197F886
| ML20197F886 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 12/18/1997 |
| From: | Huffman W NRC (Affiliation Not Assigned) |
| To: | Liparulo N WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| References | |
| NUDOCS 9712300315 | |
| Download: ML20197F886 (3) | |
Text
{{#Wiki_filter:,.. 3 December 18, 1997 Mr. Nicholas J. Liparuto, Manager . Nuclear Safety and Regdatory Analysis Nuclear and Advanced Technology Division Westinghouse Electric Corporation ; P.O. Box 355 Pittsburgh, PA 15230
SUBJECT:
OPEN ITEMS ASSOCIATED WITH iHE AP600 PASSIVE CORE COOLING SYSTEM SAFETY EVALUATION REPOHT (SER)
Dear Mr. Uparulo:
The Reactor Systems Branch of the U.S. Nuclear Regulatory Commission has provided a draft : SER inpi * (Section 6.3) to the Standardization Project Directorate on the AP600 passive core cooling system. The input has open items which have been extracted and designated as final safety evaluation report open items in the enclosure to this letter, if you have any questions regarding this matter, you may contact me at (301) 415-1141. Sincerely, original signed by: William C. Huffman, Project Manager Standardization Project Directorate Division of Reactor Program Management Office of Nuclear Reactor Regulation I Docket No. 52-003 / p*@gn 4gg [fj.
Enclosure:
. As stated _i O C bug [Qw by,@M f cc w/ encl: See next page m JI . DISTRIBUTION: T Docket File. PDST R/F TQuay PUBLIC TKenyon WHuffman JSebrosky DScaletti 'JNWilson ACRS (11) WDean,0 5 E23 JMoore,0-15 B18 GHsii,0 8 E23 RCaruso,0-8 E23 TCollins,0-8 E23 SNewberry,0-8 E2 GHolahan,0-8 E2 DOCUMENT NAME: A:SER-6-3.Ol . To receive a copy of this document, Indicate in th box: "C" = Copy without attachment / enclosure "E" = C r; 9 with rttachment/ enclosure N" = No copy .WA> 6 OFFICE PM:PDST:DRPM l-BC:SRXB:DSSA lA/ D:PDST:DRPM l l NAME-WCHuffmart@ f, A TCollins dfi) TRQuay 1)R) DATE-12 0 /97 1 2// 7/97-12/(y/97' OFFICIAL RECORD COPY 9712300315 971218 PDR ADOCK 05200003 E pm ll ll H.il. l.li I.ll. 4
c - Mr. Nicholas J Liparuto L Docket No. 52@3 1 Westinghouse Electric Corporation AP600 cc: Mr. B. A. McIntyre, - Mr. Russ Bell - Advanced Plant Safety & Licensing Senior Project Manager, Programs i ~ Westinghouse Electric Corporation Nuclear Energy institute.- Energy Systems Business Unit 1776 l Street, NW P.O. Box 355 Suite 300 Pittsburgh, PA 15230 - Washington, DC 20006-3706. Ms. Cindy L Haag Ms. Lynn Connor Advanced Plant Safety & Licensing Doc-Search Associates' Westinghouse Electric Corporation Post _Ofree Box 34 Energy Systems Business Unit - Cabin John, MD 20818 Box 355 - d. Pittsburgh, PA 15230 Dr. Craig D. Sawyer, Manager Advanced Reactor Programs Mr. Sterling Franks GE Nuclear Energy U.S. Department of Energy 175 Curtner Avenue, MC 754 - NE 50 San Jose, CA 95125 19901 Germantown Road Germantown, MD 20874 Mr. Robert H. Buchholz GE Nuclear Energy 4 Mr. Frank A. Ross 175 Curtner Avenue, MC 781 U.S. Department of Energy, NE-42 San Jose, CA 95125 Office of LWR Safety and Technology 19901 Germantown Road Barton Z. Cowan, Esq. Germantown, MD 20874 Eckert Seamans Cherin & Mellott 600 Grant Street 42nd Floor - i Mr. Charles Thompson, Nuclear Engineer Pittsburgh, PA 15219 AP600 Certification NE 50 Mr, Ed Rodwell, Manager - 19901 Germantown Road PWR Design Certification i Germantown, MD 20874 Electric Power Research Institute 3412 Hillview Avenue Mr. Robert Maiers, P.E. Palo Alto, CA 94303 Pennsylvania Department of - Environmental Protection Bureau of Radiation Protection . Rachel Carson State Office Building P.O. Box 846g Harrisburg, PA. 17105-8469 ty 3 I j y w.3 7.-.. ~~ 7.. = 1
OPEN ITEMS ASSOCIATED WITH - REACTOR SYSTEMS BRANCH EVALUATION OF 4 ~ THE AP600 PASSIVE 00RE COOLING SYSTEM, SER 6.3 440.793F Severalimportant parameters of the PXS systems, which affect passive system performance and are input parameters to the safety analyses of the design basis events, are not specified in the SSAR. These include the following: (a) The elevation of passive core cooling components relative to the RCS loops, including - CMTs - PRHR Heat Exchanger - IRWST injection Sumps 2 - Containment Recirculation Sumps - 1 (b) The piping flow resistances (including valves and spargers where applicable) associated with the - CMTs PRHR Heat Exchanger ~ - IRWST Injection a - Containment Recirculation - ADS stages 1,2,3, and 4 - Accumulators (c) Flow area of the ADS spargers These parameters are inputs to the safety analyses of the design basis transients and accidents to demonstrate the PXS mitigation capability, TM values of these parameters with allcwance for uncertainties should be also be specified in the n iAR. This is open item. 440.794F The ADS consists of four different stages of valves with a total of 20 valves. The first three stages each have two lines and each line has two normally closed, de motor-operated valves in series, one termed an isolation valve and the other a control valve The isolation valves are gate valves, and the control valves are globe valves. Section 6.3.2.2.8.5 of SSAR inconsistently states that each line in the first three stages has two identical valves in series. This inconsistent statement should be corrected in the next SSAR revision. This is an open item. I NOTE: Containment Emergency Sump Performance The susceptibility of the containment recirculation sump to blockage is an opon item in the Reactor Systems Branch SER on the passive core cooling system. This issue has already been - captured by FSER open item 650.10F (OITS #5972) related to Unresolved Safety issue A-43, - Containment Emergency Sump Performance. The staff is reviewing Westinghouse letter NSD-PRC-97-5441, dated November 21,1997, which responds to the staff concems on sump performance, however, the staff still considers this an open item. It has been included again to emphasize the importance of the resolution of this issue, i II l. Enclosure - lc. , = - =}}