ML20154G992

From kanterella
Jump to navigation Jump to search
Summary of 880331 Meeting W/Sandia Natl Lab,Numarc,Epri, Saic,Util,Westinghouse & ERC Intl Re Differences Between Industry Sponsored Analysis & Earlier Analysis of Same Plant Sponsored by NRC
ML20154G992
Person / Time
Site: Point Beach  NextEra Energy icon.png
Issue date: 04/26/1988
From: Woods R
NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES)
To: Kniel K
NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES)
Shared Package
ML20154G997 List:
References
NUDOCS 8805250187
Download: ML20154G992 (4)


Text

_ _ - - .

APR 2 01988 MEMORANDUM FOR: Karl Kniel, Chief Reactor and Plant Safety Issues Branch Division of Reactor and Plant Systems, RES FROM: Roy Woods, Senior Task Manager Reactor and Plant Safety Issues Branch Division of Reactor and Plant Systems, RES

SUBJECT:

SUMMARY

OF MARCH 31, 1988 MEETING TO DISCUSS REANALYSIS OF DHR RISK AT POINT BEACH, WITH FOLLOWUP CORRESPONDENCE The meeting was held as described in the Meeting Notice (Attachment A).

In attendance were representatives from the NRC Staff, Sandia National Laboratory, NUMARC, EPRI, SAIC, Wisconsin Electric Power, Westinghouse, Southern Co. Services, CFA, Inc., and ERC International, as indicated on the attached Attendance sheet (Attachment B).

A package of material was distributed at the meeting (Attachment C) consisting of: (1) the subject EPRI/WOG/NUMARC analysis ("EPRI/W0G Analysis of Decay Heat Removal Risk at Point Beach," NSAC/113, March,1988); (2) a package of slides that were presented at the meeting ("Differences between Sandia and NUMARC Analysis of Deca)" Heat Pemoval Related Risk for Point Beach," 31 March 1988 Whit meeting (letter to Ms. Elaine Gorham-Bergeron, SNL, from Mr. John J. Haugh, NSAC, March 31, 1988, with attached ENCLOSURE, "Responses to SNL Questions on EPRI/WOG Analysis of DHR at Point Beach," March 30, 1988); (4) .1 set of three slides consisting of one map and two handwritten sheets regarding seismic hazards at various sites; and (5) a Sandia submittal for discussion at the meeting ("Supplemental Analyses and Coments/ Responses to EPRI/WOG Analysis of Decay Heat Removal Risk at Point Beach," by David M. Ericson, Jr. , ERC International for Sandia National Lab. , Final Draf t dated March 30,1988).

The purpose of the meeting was to discuss differences between the subject industry-sponsored analysis of Point Beach, and an earlier analysis of the same i plant which was sponsored by the NRC steff and performed by SNL as part of the resolution of Unresolved Safety Issue (USI) A-45, "Decay Heat Removal Requirements." The objective of the meeting was to provide the NRC Staff with sufficient infonnation to allow completion of a preliminary staff evaluation of the industry-sponsored analysis. An earlier meeting had been held, during which NRC Staff representatives had outlined the subjects (to be discussed at this meeting) where more information was needed from industry representatives as bases for the industry sponsored study (Memorandum to farl Kniel, NRC, from Roy Woods, NRC, "Minutes of Feb. 23, 1988 Meeting with Sandia and NUMARC Regarding EPRI/WOG/NUMARC Analysis of One USI A-45 Plant," March 3, 1988).

8805250187 800426 PDR P ADOCK 05000266 PDR j

Discussions concentrated on exploring core melt frequency differences, with a minor portion of the meeting devoted to cost and consequence differences as time permitted.

The package distributed at the meeting (Attachment C) presents the subjects discussed at this meeting in some detail. That level of detail will therefore not be re-iterated in this Sumary.

In summary, it was considered reasonable by the NRC Staff and Sandia representatives to allow more credit for lower frequency of the SBLOCA, presence of the new batteries, and lack of dependence of the SI pumps upon availability of the CCW system (the SOLOCA frequency change is the dominant one) as proposed in the EPRI/WOG study. It was not considered prudent by NRC/SNL to allow more credit for many of the operator recovery actions proposed ,

l in the EPRI/WOG study, The NRC staff believes that the approximate core damage frequency that would result from use of these agreements in a "revised" NRC staff sponsored analysis would be about 9E-05 per reactor year. This is below the NRC/SNL case study calculated value of 3E-04 per reactor year, and above the industry-sponsored study calculated result of IE-05 per reactor year.

Additional details concerning differences between the two analyses are d documented in Enclosure D. The material in this Enclosure was not presented at the meeting. Rather, it was produced as a result of the meeting and in fulfillment of the above stated objective of the meeting, to enable the NRC Staff to write a preliminary evaluation of the industry sponsored Point Beach Analysis. The material is presented with these minutes in order to provide a more complete, coherent record in one place for later reference. Enclosure D consists of the following: (1) Appendix D: Insights Gained From Industry-Sponsored Study of Point Beach, from the NRC Staff's Regulatory and Backfit Analysis: Unresolved Safety Issue A-45, Shutdown Decay Heat Removal Requirements, NUREG-1289 (Draf t), April,1988; (2) Letter from E. Bergeren (SNL) to R. Woods (NRC) April 27, 1988, with attached "Supplemental Analyses and Coments/ Responses to EPRI/WOG Analysis of Decay Heat Removal Risk a- Point Beach" by D. Ericson, Jr., ERC International, April ?5, 1988.

Roy Woods, Senior Task Manager Reactor and Plant Safety Issues Branch Division of Reactor and Plant Systems, RES DISTRIBUTION: RWoods FCoffman RPSIB R/F 'PDR-BSheron Ofc. of the Secy of the Commmission WMinners MCunningham Meeting Attendees JMurphy GMazetis ARubin CFC: RPSIB/DRPS

  • RPSIB/DRPS * *see previous concurrences NAME: RWoods:sd GMazetis DATE: 4/ /88 4/ /88 l

Discussions concentrated on exploring core melt frequency differences, with a minor portion of the meeting devoted to cost and consequence differences as i time permitted. ,

i The package distributed at the meeting (Attachment C) presents the subjects l discussed at this meeting in some detail. That level of detail will therefore i not be re-iterated in this Sumary. l In summary, it was considered reasonable by the NRC Staff and ndi a representatives to allow more credit for lower frequency of th SBLOCA presence of the new batteries, and lack of dependence of the SI upon availability of the CCW system (the SBLOCA frequency change is the dominant one) as proposed in the EPRI/W0G study. It was not considered prudent by NRC/SNL to allow more credit for many of the operator recovery actions proposed in the EPRI/WOG study.

The NRC staff believes that the approximate core damage frequency that would result from use of these agreements in a "revised" NRC staff sponsored analysis would be about 9E-05 per reactor year. This is below the NRC/SNL case study calculated value of 3E-04 per reactor year, and above the industry-sponsored study calculated result of IE-05 per reactor year.

Additional details concerning differences between the two analyses are documented in Enclosure D. The material in this Enclosure was not presented at the meeting. Rather, it was produced as a result of the meeting and in fulfillment of the above stated objective of the meeting, to enable the NRC  !

Staff to write a preliminary evaluation of the industry sponsored Point Beach )

Analysis. The material is presented with these minutes in order to provide a  ;

more complete, coherent record in one place for later reference. Enclosure D l consists of the following: (1) Appendix D: Insights Gained From I Industry-Sponsored Study of Point Beach, from the NRC Staff's Regulatory and Backfit Analysis: Unresolved Safety Issue A-45, Shutdown Decay Heat Removal i Requirements, NUREG-1289 (Draf t), April,1988; (2) Letter from D. Erickson, ERC l International, to R. Woods, NRC Staff, with attached additional comments regarding the EPRI/WOG analysis, April 26, 1988.

Roy Woods, Senior Task Manager Reactor and Plant Safety Issues Branch Division of Reactor and Plant Systems, RES DISTRIBUTION:

RPSIB R/F POR BSheron Office of the Secretary of the Comission WMinners MCunningham fleeting Attendees JMurphy GMazetis A bbin RWoods F man 0FC: RPS / RPS R '! DRPS NAME: RWoods:sd G e is DATE: 4/m/88 4$ /88

A bbAe d 8 Arrsro z;woct .

(3 /3i/n )

wue samanoo >ewca Je<< A4yae sac /as/ ness (pl} n2-3ssh C ul) Y12 - 3 r-c k % d .'s ac~ 9 er ~ ~ 6ai La boeJ ~ so5 W -sis I (fop <- /Vewy\ Wisav:,, Eh<f,ic A m e (914) 22/ -2cc a 1%v Hwem tuco,u;n steesse. Am a- (9/9 ) >> > - a 0 09 Z>m 7h+ a 4 / we>nyAnse riw& (qis)-3 w-isn sio few ' ive/ acsj' teos (30) 192 3 7 n Otu M $1cHTiit WAQ2u/Ahp cm) 'It2-5 74 s Ii Aw n m . M p u n n 1.u c, gourytn?v go, 97fu g em ( y o g ) 9 7 7 . -7 ; 7 4

/ F1 6&f4 d d [/7 ~~IedC Q O /) 9lo 3 -TYf[

Vcc-c,z- l-h,sw:.> rdbmac (z.cd 8?z-izsa y;z c jjy g.S / piz,+. 75 ( $ o 1 ) u co 3 's 4 a- '

H cvretd %~a>cte</A ei a b' b ~C'Ad 9, (1.3 Ql.L (N)G.f.,hg3 [pR. A f5 h5e d 4.3 Z,- 1Ci i $

4tY~-9(,o .C719

$ll Puk^W .~%rc EJ D- -

'e le , L.

c

!iGt c f, t? - q R7 -. 6 79 =

l'$l ' l bU.?$i$,'? ,?  !'.?f.', a@ d, )d [:f- f) / 9 wi < , twos ss s ss s n - =.u s D At,.a M . a % J & - Ees. wnmnx.N (ph can) cos-l'2n -gye 0, a: .~ , 2 .  !. . . ,,. A ,, a;, & .4.ts a .: m. . + c.w IVRcfpg3/NAA fol f/2 - M I 'i L.JW[fA Gws % c44 Wn w at un - gn - i zg6 d Acn H A u ca s c PR_L, _

A is - ess -yp,6 6caat W ts encs use/Numu sa h e iz. - 3 37-po a I. 2 ;, m @~ ) tac / (m)vu- w

1. . :t n EeRz

)