ML18057B532

APR1400-E-N-NR-14001-NP, Rev.3, Design Features to Address GSI-191.

ML18057B532
Person / Time
Site:	05200046
Issue date:	02/28/2018
From:	Korea Electric Power Corp, Korea Hydro & Nuclear Power Co, Ltd
To:	Office of New Reactors
Shared Package
ML18057B526	List: ML18057B527 ML18057B529 ML18057B532
References
MKD/NW-18-0031L APR1400-E-N-NR-14001-NP, Rev.3
Download: ML18057B532 (330)

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Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Design Features to Address GSI-191 Revision 3 Non-Proprietary February 2018 Copyright 2018 K orea Electric Pow er Corporation &

K orea H ydro & Nuclear Pow er Co., Ltd All Rights Reserved KEPCO & KHNP i

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 REVISION HISTORY Section(s) or Revision Date Description Page(s)

Dec em b er 0 Al l First Issue 2014 Added th e desc rip tion of h ow th e NRC guidanc e on Sec tions c h em ic al ef f ec ts is ap p l ied to th e APR1400 c h em ic al 2.6, 3.8, 6 ef f ec ts eval uation and added th e ref erenc es ( p er RAI 391-8462 Q 34)

Added th e j ustif ic ation of assum p tion th at al l c oating Sec tion 3.3 deb ris are in a sm al l p artic ul ate f orm ( p er RAI 391-8462 Q 32)

Correc ted th e deb ris transp ort l oc ation ( p er RAI 25-Sec tion 3.4 7844 Q 10) .

Sup p l em ented th e desc rip tion of th e unc ertainty in Sec tion 3.6.2 NPSHr f or th e SI p um p s and CS p um p s ( p er RAI 25-7844 Q 6)

Sec tions Disc ussed L OCA w ater p H val ues f or th e sh ort-term 3.8.1, 3.8.2, and l ong term DB A c ondition ( p er ac tion item 6-19 Q 8 and and Q 8 R1)

T ab l e 3.8-1 Revised th e assum p tion f or th e IRW ST w ater vol um e Sec tion 3.8.2

( p er ac tion item 6-19 Q 6)

Del eted th e assum p tion f or th e tem p erature p rof il es Sec tion 3.8.2

( p er RAI 404-8488 Q 11)

Sec tion 3.8.2 1 M arc h 2017 Revised th e p H c urve in th e c h em ic al ef f ec ts anal y sis and

( p er RAI 391-8462 Q 38)

Figure 3.8-1 Cl arif ied th e op erating tim e of th e CSS used in th e Sec tion 3.8.2 c h em ic al ef f ec ts anal y sis ( p er ac tion item 6-19 Q 9 R1)

Sec tions 3.6.2, 3.9.1, Correc ted th e m inim um NPSH m argins f or th e SI 3.9.2, p um p s and CS p um p s and c l arif ied th e m inim um w ater and l evel of IRW ST f or ESF op eration ( p er 6.3 NPSH Audit)

Figure 3.9-3 Added th e ref erenc e f or density val ues f or ep ox y and T ab l e 3.3-2 inorganic z inc c oatings ( p er RAI 391-8462 Q 33)

Added th e b asis of 10% m argin in th e duc t insul ation T ab l e 3.8-2 area ( p er ac tion item 6-19 Q 10)

U p dated th e c h em ic al ef f ec ts anal y sis inp uts and T ab l es resul ts b ased on th e up dated tem p erature p rof il es ( p er 3.8-4, 3.8-5 RAI 391-8462 Q 35)

Sec tion 4.2 Cl arif ied th e statem ent ( p er RAI 63-7983 Q 12)

Sec tion Revised Sec tion 4.2.2.3 to b e c onsistent w ith T ab l e 4.2-4.2.2.3, 1 and up dated th e l ist of th e SIS and CSS c om p onents and th at need to b e inc l uded in th e dow nstream ef f ec ts T ab l e 4.2-1 eval uation ( p er RAI 63-7983 Q 13)

KEPCO & KHNP i

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Section(s) or Revision Date Description Page(s)

Sec tions Added th e w ear rate inf orm ation w ith resp ec t to th e 4.2.2.4, 6, various sy stem m aterial s inc l uding ref erenc es ( p er RAI and 63-7983 Q 26)

T ab l e 4.2-8 Sec tions 4.2.2.5, Sim p l if ied th e f l ow rates of SIS and CSS assum ed f or 4.2.2.6, th e c om p onent w ear rate eval uation, inc orp orated th e 4.2.3.3.2, revised th e deb ris c onc entration to th e w ear rate and eval uation, and c l arif ied th e m inim um IRW ST w ater T ab l es vol um e f or ESF op eration ( p er RAI 63-7983 Q 16) 4.2-5, 4.2-7 Added th e m issing test c ondition f or SIS and CSS Sec tion p um p s to b e c onsistent w ith Sec tion 4.2.3.1 ( p er RAI 4.2.2.5 63-7983 Q 15)

Sec tions Sp ec if ied th at th e p um p and val ve q ual if ic ation w il l b e 4.2.3.1, ac c om p l ish ed b y test or a c om b ination of test and 4.2.3.2.2, anal y sis in ac c ordanc e w ith ASM E Q M E-1-2007 ( p er 4.2.3.3.2 RAI 63-7983 Q 17 and Q 18)

Sec tions Added th e eval uation f or th e ef f ec ts of p ost-L OCA 4.2.3.2, deb ris f or th e CS p um p m inif l ow h eat ex c h angers ( p er 4.2.3.2.1, RAI 266-8338 Q 31) 4.2.3.2.2 Sp ec if ied th at h eat ex c h anger p l ugging, f oul ing, w ear Sec tion and h eat transf er p erf orm anc e in th e p resenc e of p ost-4.2.3.2 L OCA deb ris w il l b e eval uated b y th e vendor during th e p roc urem ent p roc ess ( p er RAI 63-7983 Q 20) 1 M arc h 2017 Added th e design inf orm ation f or th e m inim um f l ow Sec tion vel oc ity th rough th e h eat ex c h anger tub es ( p er RAI 63-4.2.3.2 7983 Q 19)

Sec tion Added c onservative assum p tions to eval uate deb ris 4.2.3.3.1, settl ing in p ip ing, val ves, orif ic es, and sp ray noz z l es and and revised T ab l e 4.2-6 to sim p l if y th e assum ed T ab l es c om p onent f l ow rates and vel oc ities ( p er RAI 63-7983 4.2-6, 4.2-9 Q 22)

Sec tion Added th e desc rip tion of deb ris settl ing in gl ob e val ves 4.2.3.3.1 ( p er RAI 63-7983 Q 23)

Sec tion Added th e eval uation of w ear rate f or th e c ontainm ent 4.2.3.3.2 sp ray noz z l es ( p er RAI 63-7983 Q 21)

Sec tion Added th e CSS val ve q ual if ic ation ( p er RAI 63-7983 4.2.3.3.2 Q 25)

Added th e eval uation and verif ic ation of th e p otential Sec tion inc rease in f l ow rates in th e ECCS and CSS due to 4.2.3.3.2 c om p onent w ear ( p er RAI 63-7983 Q 24 R1)

Cl arif ied th e instrum ent c onnec tion l oc ations in Sec tion instrum ent tub ing c l ogging eval uation ( p er RAI 63-7983 4.2.3.4 Q 27)

Added th e c h em ic al ef f ec ts eval uation f or th e CS Sec tion p um p s and c ontainm ent sp ray noz z l es ( p er RAI 63-4.2.3.5 7983 Q 29)

Sec tions 3.6.1, 4.3.2.2, Revised th e start tim e of h ot l eg sw itc h over op eration and 4.3.5 KEPCO & KHNP ii

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Section(s) or Revision Date Description Page(s)

Sec tions 4.3.3.1, 4.3.3.2, 4.3.3.3, Revised th e b asis of dow nc om er l iq uid density and th e 4.3.4.5, 4.3.6, rel ated avail ab l e driving h eads f or eac h L OCA sc enario 4.3.7, and

( p er RAI 404-8488 Q 11)

T ab l es 4.3-3, 4.3-4, 4.3-5, 4.3-8, 4.3-12 1 M arc h 2017 Sec tions 4.3.4.3, 4.3.4.4.1, 4.3.4.4.2, Revised th e assum p tion of th e RV c ool ant tem p erature T ab l es and th e eval uation of dep osition on th e f uel ( L OCADM )

4.3-6, 4.3-7, ( p er RAI 404-8488 Q 11 and Q 11 R1) and Figures 4.3-6, 4.3-7 Sec tion 6 U p dated th e ref erenc es Revised th e assum p tion of th e m ax im um IRW ST w ater Sec tion 3.8.2 vol um e w ith j ustif ic ation ( p er RAI 520-8693 Q 42)

Sec tions Revised th e ECCS and CSS p um p s and val ves w ear 4.2.3.1 and eval uation ( p er RAI 63-7983 Q 18 R2) 4.2.3.3.2 Sec tions Revised th e w ear eval uation of th e p ip ing, sp ray 4.2.3.2.2, noz z l es, and orif ic es and added th e overal l sy stem 4.2.3.3.2, and eval uation ( p er RAI 63-7983 Q 24 R2) 4.2.4 Sec tion Revised th e f l uid f l ow vel oc ities b ased on ex p ec ted 2 Oc tob er 2017 4.2.3.3.1, and p um p op eration ( Per RAI 543-8734 Q 46)

T ab l e 4.2-9 Sec tion 4.2.3.3.1, and Revised th e deb ris settl ing eval uation ( p er RAI 63-7983 T ab l es 4.2-6 Q 22 R1) and 4.2-9 Added, c h anged, or del eted th e SI and CS c om p onents T ab l e 4.2-1 req uired to b e inc l uded in th e dow nstream ef f ec ts eval uation ( p er RAI 63-7983 Q 13 R1)

Revised th e c om p onent w ear rate eval uation ( p er RAI T ab l e 4.2-7 63-7983 Q 16 R1)

Sec tions 3.8.2, 4.3.2, Feb ruary and 6, and Revised th e assum p tion and c al c ul ation resul ts of 3

2018 T ab l es 3.8-4, c h em ic al ef f ec ts anal y sis ( p er RAI 520-8693 Q 43) 3.8-5, and 4.3-2 KEPCO & KHNP iii

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 This document was prepared for the design certification application to the U.S. Nuclear Regulatory Commission and contains technological information that constitutes intellectual property of Korea Hydro & Nuclear Power Co., Ltd..

Copying, using, or distributing the information in this document in whole or in part is permitted only to the U.S.

Nuclear Regulatory Commission and its contractors for the purpose of reviewing design certification application materials. Other uses are strictly prohibited without the written permission of Korea Electric Power Corporation and Korea Hydro & Nuclear Power Co., Ltd.

KEPCO & KHNP iv

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 ABSTRACT T h is tec h nic al rep ort desc rib es th e design f eatures of th e APR1400 th at address Generic Saf ety Issue

( GSI) -191 ( NU REG/ CR-6874, Ex p erim ental Studies of L oss-of -Cool ant-Ac c ident-Generated Deb ris Ac c um ul ation and Head L oss w ith Em p h asis on th e Ef f ec ts of Cal c ium Sil ic ate Insul ation ) . T h is rep ort al so p rovides an assessm ent of th e APR1400 design b ased on th e guidanc e and req uirem ents in Nuc l ear Energy Institute 04-07, Pressuriz ed W ater Reac tor Sum p Perf orm anc e Eval uation M eth odol ogy , and th e assoc iated NRC Saf ety Eval uation ( Saf ety Eval uation b y th e Of f ic e of Nuc l ear Reac tor Regul ation Rel ated to NRC-Generic L etter 2004-02 ) , as w el l as industry guidanc e and industry testing to address and resol ve GSI-191 issues.

Eval uations are c onduc ted of th e ef f ec ts of design b asis ac c ident c onditions on th e ab il ity of struc tures, sy stem s, and c om p onents to m itigate th e c onseq uenc es of th e ac c idents and to m aintain l ong-term c ore c ool ing in a m anner c onsistent w ith th e governing regul atory req uirem ents of NRC Regul atory Guide 1.82

( Rev.4) .

T h e APR1400 is designed as a l ow f ib er p l ant to resol ve GSI-191 issues b y ap p l y ing th e l essons l earned f rom op erating p l ants and b y using industry trends rel ated to th e resol ution of th e GSI-191 issue, inc l uding th e ex c l usion of f ib rous m aterial w ith in th e z one of inf l uenc e of a h igh -energy l ine b reak .

KEPCO & KHNP v

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TABLE OF CONTENTS 1 INTRODUCTION ..................................................................................................... 1 2 DESIGN DESCRIPTION .......................................................................................... 2 2.1 Em ergenc y Core Cool ing/ Containm ent Sp ray Sy stem ................................................................ 2 2.2 In-Containm ent Ref uel ing W ater Storage T ank ........................................................................... 3 2.3 Design f or Prevention of Degraded Em ergenc y Core Cool ing Sy stem Perf orm anc e ................. 3 2.4 IRW ST Sum p Strainer ................................................................................................................. 4 2.5 Insul ation ...................................................................................................................................... 4 2.6 Coatings ....................................................................................................................................... 5 3 EVALUATION OF IRWST SUMP STRAINER PERFORMANCE ............................... 11 3.1 B reak Sel ec tion .......................................................................................................................... 11 3.1.1 Ac c ident Sc enarios .................................................................................................................. 11 3.1.2 Sel ec tion of th e Postul ated B reak L oc ation ............................................................................ 12 3.2 Deb ris Generation ...................................................................................................................... 14 3.3 Deb ris Ch arac teristic s ................................................................................................................ 14 3.4 Deb ris T ransp ort ........................................................................................................................ 16 3.5 Deb ris Head L oss ...................................................................................................................... 17 3.5.1 IRW ST Sum p Strainer Design Conditions ............................................................................... 17 3.5.2 IRW ST Sum p Strainer Siz ing .................................................................................................. 17 3.5.3 IRW ST Sum p Strainer Head L oss ........................................................................................... 17 3.6 Net Positive Suc tion Head ......................................................................................................... 19 3.6.1 Sy stem Op eration .................................................................................................................... 19 3.6.2 Avail ab l e NPSH Cal c ul ation .................................................................................................... 20 3.6.3 Cavitation Erosion ................................................................................................................... 24 3.7 Strainer V ortex ing, Air Inj ec tion, Fl ash ing, and Deaeration Assessm ent ................................... 25 3.7.1 Strainer V ortex ing .................................................................................................................... 25 3.7.2 Fl ash ing in th e Deb ris B ed ...................................................................................................... 25 3.7.3 Deaeration of Sum p Fl uid at Strainer ...................................................................................... 25 3.8 Ch em ic al Ef f ec ts ........................................................................................................................ 26 3.8.1 Containm ent Sp ray p H Control ............................................................................................... 26 3.8.2 Assum p tions ............................................................................................................................ 26 3.8.3 Eval uation Sum m ary ............................................................................................................... 27 3.9 U p stream Ef f ec t ......................................................................................................................... 28 3.9.1 Hol dup V ol um es ...................................................................................................................... 28 KEPCO & KHNP vi

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.9.2 M inim um W ater L evel f or ESF op eration ................................................................................ 30 4 DOWNSTREAM EFFECTS ..................................................................................... 57 4.1 Strainer B y p ass T esting ............................................................................................................. 57 4.2 Ex -V essel Dow nstream Ef f ec ts .................................................................................................. 58 4.2.1 Sy stem Desc rip tions ................................................................................................................ 58 4.2.2 Design Inp uts/ Eval uation Assum p tions ................................................................................... 60 4.2.3 ECCS Com p onent Eval uations ............................................................................................... 64 4.2.4 Overal l Sy stem Eval uation ...................................................................................................... 69 4.2.5 Eval uation Sum m ary ............................................................................................................... 69 4.3 In-V essel Dow nstream Ef f ec ts ................................................................................................... 70 4.3.1 ECCS Fl ow Rates ................................................................................................................... 70 4.3.2 Am ount of B y p ass Deb ris p er Fuel Assem b l y ......................................................................... 72 4.3.3 Avail ab l e Driving Head ............................................................................................................ 75 4.3.4 L OCADM Cal c ul ations ............................................................................................................ 77 4.3.5 B oric Ac id Prec ip itation ............................................................................................................ 84 4.3.6 Fuel Assem b l y T esting ............................................................................................................. 84 4.3.7 Eval uation Sum m ary ............................................................................................................... 85 5 CONCLUSION .................................................................................................... 123 6 REFERENCES .................................................................................................... 124 Appendix A Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements ......................................................................................... A1 Appendix B Debris Generation Evaluation for the APR1400 .................................... B1 Appendix C Head Loss Test Report for the IRWST Sump Strainer .......................... C1 Appendix D Bypass Test Report for the IRWST Sump Strainer ............................... D1 Appendix E Structural Drawings ............................................................................... E1 KEPCO & KHNP vii

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF TABLES T ab l e 3.1-1 Postul ated B reak Pip e L ines .................................................................................................. 31 T ab l e 3.2-1 Deb ris Generation f or B reak L oc ations .................................................................................. 32 T ab l e 3.3-1 Siz e and Distrib ution of Deb ris............................................................................................... 33 T ab l e 3.3-2 Deb ris Prop erties ................................................................................................................... 34 T ab l e 3.6-1 NPSHr f or SI Pum p and CS Pum p ........................................................................................ 35 T ab l e 3.6-2 SI Pum p NPSH Eval uation Resul ts ....................................................................................... 36 T ab l e 3.6-3 CS Pum p NPSH Eval uation Resul ts ...................................................................................... 37 T ab l e 3.8-1 Post-L OCA IRW ST Ch em istry ............................................................................................... 38 T ab l e 3.8-2 M aterial Potential l y Produc ed Corrosion Produc ts ................................................................ 39 T ab l e 3.8-3 Inp ut Data f or W CAP-16530-NP Ch em ic al Produc t Form ation ............................................. 40 T ab l e 3.8-4 W CAP-16530 Resul ts Sum m ary ............................................................................................ 41 T ab l e 3.8-5 Resul ts f or th e APR1400, M ax im um W ater V ol um e, M inim um ECCS Fl ow .......................... 42 T ab l e 3.9-1 U p stream Ef f ec ts on Hol dup V ol um e ..................................................................................... 43 T ab l e 4.1-1 Strainer Fl ow Rate and Deb ris L oads .................................................................................... 87 T ab l e 4.1-2 B y p ass Fib er W eigh t .............................................................................................................. 88 T ab l e 4.1-3 B y p ass Deb ris Q uantities of IRW ST Sum p Strainer .............................................................. 89 T ab l e 4.2-1 Com p onents in th e Fl ow Path during an L B L OCA ( 1 of 3) .................................................... 90 T ab l e 4.2-2 Siz e Range of Deb ris M aterial s ............................................................................................. 93 T ab l e 4.2-3 T otal Q uantity of Deb ris Generated during an L B L OCA ........................................................ 94 T ab l e 4.2-4 T erm inal Settl ing V el oc ity of Deb ris Sourc e M aterial s ........................................................... 95 T ab l e 4.2-5 Post-L OCA Fl uid Constituents Dow nstream of IRW ST Sum p Strainer ................................. 96 T ab l e 4.2-6 Af f ec ted Eq uip m ent/ Fl ow Rates ( 1 of 2) ................................................................................ 97 T ab l e 4.2-6 Af f ec ted Eq uip m ent/ Fl ow Rates ( 2 of 2) ................................................................................ 98 T ab l e 4.2-7 ECCS and CSS Com p onents W ear during 30 day s .............................................................. 99 T ab l e 4.2-8 W ear Rates of M aterial under Ab rasive Sl urries .................................................................. 100 T ab l e 4.2-9 Pip ing and Assoc iated V al ves w ith L ow er Assum ed Fl ow V el oc ity th an Settl ing V el oc ity ... 101 T ab l e 4.3-1 ECCS Fl ow Rates p er FA Fol l ow ing a L OCA ...................................................................... 102 T ab l e 4.3-2 B y p ass Deb ris T y p es and Am ounts p er FA ......................................................................... 103 T ab l e 4.3-3 Inp uts f or Cal c ul ation of Hot-l eg dPavail ................................................................................ 104 T ab l e 4.3-4 Inp uts f or Cal c ul ation of Col d-l eg dPavail .............................................................................. 105 T ab l e 4.3-5 Inp uts f or Cal c ul ation of Col d-l eg af ter HL SO dPavail ........................................................... 106 T ab l e 4.3-6 T im e Dep endent T em p erature Data ..................................................................................... 107 T ab l e 4.3-7 Containm ent M aterial Inp ut .................................................................................................. 108 T ab l e 4.3-8 Cool ant M aterial Inp uts ........................................................................................................ 109 T ab l e 4.3-9 Core M odel ing Param eters ................................................................................................... 110 KEPCO & KHNP viii

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-10 Ax ial Nodal iz ation and Inp ut V al ues.................................................................................... 111 T ab l e 4.3-11 Radial Nodal iz ation and Inp ut V al ues ................................................................................. 112 T ab l e 4.3-12 Sum m ary of Fuel Assem b l y T est Resul ts............................................................................ 113 KEPCO & KHNP ix

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF FIGURES Figure 2.2-1 Pl an V iew of IRW ST ............................................................................................................... 6 Figure 2.2-2 IRW ST Sum p Pit El evation V iew ............................................................................................ 7 Figure 2.4-1 IRW ST Sum p Strainer ............................................................................................................ 8 Figure 2.4-2 IRW ST Sum p Strainer Draw ing ( Isom etric V iew ) ................................................................... 9 Figure 2.4-3 IRW ST Sum p Strainer Draw ing ( T op and Sec tion V iew s) .................................................... 10 Figure 3.2-1 Sec tional V iew of th e Z OI f or RCS Hot L eg L ine B reak ....................................................... 44 Figure 3.2-2 Sec tional V iew of th e Z OI f or RCS Col d L eg L ine B reak ..................................................... 45 Figure 3.2-3 Sec tional V iew of th e Z OI f or M ain Steam L ine B reak ......................................................... 46 Figure 3.5-1 IRW ST Sum p Strainer Pl an and El evation V iew .................................................................. 47 Figure 3.6-1 Sc h em atic Fl ow Diagram of SI Sy stem ................................................................................ 48 Figure 3.6-2 Sc h em atic Fl ow Diagram of CS Sy stem .............................................................................. 49 Figure 3.6-3 Containm ent Pressure and T em p erature vs. T im e f or L ong-T erm Ph ase ( Doub l e-ended Disc h arge L eg Sl ot B reak w ith M inim um ECCS Fl ow ) ...................................................... 50 Figure 3.6-4 L im iting SI p um p NPSH vs. T im e ......................................................................................... 51 Figure 3.6-5 L im iting CS p um p NPSH vs. T im e ....................................................................................... 52 Figure 3.8-1 IRW ST and Containm ent Sp ray p H vs. T im e Curve used in Ch em ic al Ef f ec ts Anal y sis ..... 53 Figure 3.9-1 Sc h em atic of Containm ent Sp ray / B l ow dow n Return Path w ay s ........................................... 54 Figure 3.9-2 Sc h em atic of Potential W ater T rap s in Containm ent ............................................................ 55 Figure 3.9-3 Sc h em atic Diagram f or IRW ST W ater V ol um e ..................................................................... 56 Figure 4.3-1 B oil -of f Rate during 4 Hours ................................................................................................ 114 Figure 4.3-2 Avail ab l e Driving Head at Hot-L eg B reak Condition ........................................................... 115 Figure 4.3-3 Avail ab l e Driving Head at Col d-L eg B reak Condition.......................................................... 116 Figure 4.3-4 Avail ab l e Driving Head at Col d-L eg B reak af ter HL SO Condition ...................................... 117 Figure 4.3-5 Fl ow Path s and Def initions f or L OCADM ............................................................................ 118 Figure 4.3-6 M ax im um L OCA Sc al e T h ic k ness ....................................................................................... 119 Figure 4.3-7 Fuel Cl adding T em p erature ................................................................................................ 120 Figure 4.3-8 Pressure Drop ( APR1400-21; P: F= 1: 1, 77.6 L / m in) .......................................................... 121 Figure 4.3-9 Pressure Drop ( APR1400-95; P: F= 1: 50, 16.6 L / m in) ........................................................ 122 KEPCO & KHNP x

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 ACRONYMS AND ABBREVIATIONS AL W R advanc ed l igh t w ater reac tor APR1400 Advanc ed Pow er Reac tor 1400 ASM E Am eric an Soc iety of M ec h anic al Engineers B OP b al anc e of p l ant B W G B irm ingh am W ire Gauge CAD c om p uter-aided design CEDM c ontrol el em ent drive m ec h anism CFS c avity f l ooding sy stem CL c ol d l eg CS c ontainm ent sp ray CSAS c ontainm ent sp ray ac tuation signal CSB c ore sup p ort b arrel CSHX c ontainm ent sp ray h eat ex c h anger CSP c ontainm ent sp ray p um p CSS c ontainm ent sp ray sy stem DB A design b asis ac c ident DC dow nc om er DCD Design Control Doc um ent DV I direc t vessel inj ec tion ECCS Em ergenc y Core Cool ing Sy stem ESF engineered saf ety f eatures EPRI El ec tric Pow er Researc h Institute FA f uel assem b l y GSI Generic Saf ety Issue HEL B h igh -energy l ine b reak HL h ot l eg HL SO h ot l eg sw itc h over HV AC h eating, ventil ation, and air c onditioning HV T h ol dup vol um e tank ICI in-c ore instrum entation ID inside diam eter IOZ inorganic z inc IRW ST in-c ontainm ent ref uel ing w ater storage tank IW SS in-c ontainm ent w ater storage sy stem KEPCO Korea El ec tric Pow er Corp oration KHNP Korea Hy dro & Nuc l ear Pow er Co., L td.

L B L OCA l arge b reak L OCA L OCA l oss-of -c ool ant ac c ident L OCADM L OCA dep osition m odel L OOP l oss of of f site p ow er L T CC l ong-term c ore c ool ing M SL B m ain steam l ine b reak NEI Nuc l ear Energy Institute NPSH net p ositive suc tion h ead NPSHa avail ab l e NPSH NPSHr req uired NPSH KEPCO & KHNP x i

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 NPSHref f ef f ec tive req uired NPSH NRC Nuc l ear Regul atory Com m ission NU REG U .S. Nuc l ear Regul atory Com m ission Regul ation POSRV p il ot op erated saf ety rel ief val ve PW R p ressuriz ed w ater reac tor PW ROG PW R Ow ners Group PZ R p ressuriz er RCP reac tor c ool ant p um p RCS reac tor c ool ant sy stem RG regul atory guide RM I ref l ec tive m etal insul ation RV reac tor vessel SB L OCA sm al l b reak L OCA SC sh utdow n c ool ing SCP sh utdow n c ool ing p um p SCS sh utdow n c ool ing sy stem SE saf ety eval uation SECY Of f ic e of th e Sec retary of th e Com m ission SG steam generator SI saf ety inj ec tion SIAS saf ety inj ec tion ac tuation signal SIP saf ety inj ec tion p um p SIS saf ety inj ec tion sy stem SIT saf ety inj ec tion tank T B E th in b ed ef f ec t T SP tri-sodium p h osp h ate U GS up p er guide struc ture W CAP W estingh ouse Com m erc ial Atom ic Pow er Z OI z one of inf l uenc e KEPCO & KHNP x ii

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 1 INTRODUCTION T h e p urp ose of th is tec h nic al rep ort is to desc rib e th e design f eatures and eval uation resul ts of th e p ost-ac c ident p erf orm anc e of th e in-c ontainm ent ref uel ing w ater storage tank ( IRW ST ) sum p strainer of th e Advanc ed Pow er Reac tor 1400 ( APR1400) . T h e p urp ose is al so to c onf irm th at th e em ergenc y c ore c ool ing sy stem ( ECCS) and c ontainm ent sp ray sy stem ( CSS) rec irc ul ation f unc tions under l oading c onditions are in c onf orm anc e w ith th e ap p l ic ab l e regul atory req uirem ents of Nuc l ear Regul atory Com m ission ( NRC) Regul atory Guide ( RG) 1.82, Rev.4 ( Ref erenc e [ 1-1] ) .

T h is rep ort inc l udes:

1) Desc rip tion of th e design of th e IRW ST , ECCS p erf orm anc e, IRW ST sum p strainer, insul ation, and c oating

2) Eval uation of IRW ST sum p strainer p erf orm anc e inc l uding b reak sel ec tion, deb ris generation, c h arac teristic s, transp ort, h ead l oss, net p ositive suc tion h ead ( NPSH) f or ECCS p um p s and CSS p um p s, c h em ic al ef f ec ts, and up stream ef f ec t

3) Eval uation of dow nstream ef f ec ts

4) Conc l usion regarding th e APR1400 design f eatures in addressing Generic Saf ety Issue ( GSI) -191 in ac c ordanc e w ith SECY 0093 ( Ref erenc e [ 1-2] )

KEPCO & KHNP 1

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 2 DESIGN DESCRIPTION T h e f ol l ow ing sec tion desc rib es th e outl ines of th e c urrent APR1400 design and h ow it satisf ies th e rec om m endations of NRC RG 1.82 ( Ref erenc e [ 1-1] ) .

2.1 Emergency Core Cooling/ Containment Spray System T h e ECCS rem oves h eat f rom th e reac tor c ore f ol l ow ing p ostul ated design b asis ac c idents ( DB As) . T h e f unc tion of th e APR1400 ECCS is p erf orm ed w ith th e saf ety inj ec tion sy stem ( SIS) .

T h e SIS is c om p osed of f our indep endent m ec h anic al trains ( w ith out any c ross-tie l ine am ong th e inj ec tion p ath s) and f our indep endent el ec tric al trains. Eac h train h as one ac tive saf ety inj ec tion p um p ( SIP) and one p assive saf ety inj ec tion tank ( SIT ) eq uip p ed w ith a f l uidic devic e.

T o m itigate l oss-of -c ool ant ac c ident ( L OCA) c onditions, eac h train p rovides 50% of th e m inim um inj ec tion f l ow rate f or b reak s l arger th an th e siz e of a direc t vessel inj ec tion ( DV I) l ine. For b reak s eq ual to or sm al l er th an th e siz e of a DV I l ine, eac h train h as 100% of th e req uired c ap ac ity . T h e l ow p ressure inj ec tion p um p s w ith c om m on h eader instal l ed in th e c onventional design are el im inated, and th e f unc tions f or saf ety inj ec tion ( SI) and sh utdow n c ool ing ( SC) are sep arated.

T h e c ore c ool ing w ater is designed to b e inj ec ted direc tl y into th e reac tor vessel ( RV ) , w h ic h el im inates th e p ossib il ity of a sp il l of th e inj ec ted f l ow th rough th e b rok en c ol d l eg ( CL ) . For th is p urp ose, f our SI l ines are c onnec ted direc tl y to th e noz z l es l oc ated ab ove th e h ot l egs ( HL s) and CL s on th e up p er p ortion of th e RV .

T h e CSS is a saf ety grade sy stem designed to reduc e c ontainm ent p ressure and tem p erature f rom a m ain steam l ine b reak ( M SL B ) or a L OCA and rem ove f ission p roduc ts f rom th e c ontainm ent atm osp h ere f ol l ow ing a L OCA.

T h e CSS uses th e IRW ST and h as tw o indep endent trains th at c onsist of tw o c ontainm ent sp ray p um p s

( CSPs) , tw o c ontainm ent sp ray h eat ex c h angers ( CSHX s) , tw o c ontainm ent sp ray ( CS) m ini-f l ow h eat ex c h angers, tw o indep endent sp ray h eaders, and assoc iated p ip ing, val ves, and instrum entation. Post-ac c ident p H c ontrol of th e sp ray ed f l uid is p rovided b y using tri-sodium p h osp h ate ( T SP) th at is stored in th e h ol dup vol um e tank ( HV T ) .

T h e CSS p rovides sp ray s of b orated w ater to th e c ontainm ent atm osp h ere f rom th e up p er regions of th e c ontainm ent. T h e sp ray f l ow is p rovided b y th e CSPs w h ic h tak e suc tion f rom th e IRW ST . T h e CSPs start up on th e rec eip t of a saf ety inj ec tion ac tuation signal ( SIAS) or a c ontainm ent sp ray ac tuation signal

( CSAS) . T h e p um p s disc h arge th rough th e CSHX s and th e sp ray h eader isol ation val ves to th eir resp ec tive sp ray noz z l e h eaders, th en into th e c ontainm ent atm osp h ere.

Sp ray f l ow to th e CS h eaders is not p rovided until a CSAS autom atic al l y op ens th e CS h eader isol ation val ves. T h e sp ray h eaders are l oc ated in th e up p er p art of th e c ontainm ent b uil ding to al l ow th e f al l ing sp ray drop l ets tim e to ap p roac h th erm al eq uil ib rium w ith th e steam -air atm osp h ere. Condensation of th e steam b y th e f al l ing sp ray resul ts in a reduc tion of c ontainm ent p ressure and tem p erature.

T h e CSPs are designed to b e f unc tional l y interc h angeab l e w ith th e sh utdow n c ool ing p um p s ( SCPs) .

T h e CSPs and CSHX s c an b e used as a b ac k up to th e SCPs and SC h eat ex c h angers to p rovide residual h eat rem oval or to p rovide c ool ing of th e IRW ST . T h is design gives th e CSS h igh er rel iab il ity c om p ared w ith a c onventional p l ant.

KEPCO & KHNP 2

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 2.2 In-Containment Ref ueling Water Storage T ank T h e in-c ontainm ent w ater storage sy stem ( IW SS) p erf orm s w ater c ol l ec tion, del ivery , storage, and h eat sink f unc tions inside th e c ontainm ent during norm al op eration and ac c ident c onditions. T h e IW SS c om p rises th e IRW ST , HV T , and c avity f l ooding sy stem ( CFS) .

T h e IRW ST and HV T are integral p arts of th e internal struc ture of c ontainm ent b uil ding and reinf orc ed c onc rete struc tures w ith a stainl ess steel l iner on surf ac es ex p ec ted to b e in direc t c ontac t w ith b orated w ater. T h e IRW ST is l oc ated b el ow El . 100 f t in th e f l oor sl ab b etw een th e sec ondary sh iel d w al l outside and th e inner c ontainm ent w al l inside. T h e tank h as a c ontinuous ring around th e l ow er c ontainm ent.

T h e IRW ST is a p rotec ted, rel iab l e, and saf ety -rel ated sourc e of b orated w ater f or th e SIS and CSS. A p l an view of th e IRW ST is sh ow n in Figure 2.2-1. El evation view s of th e IRW ST sum p p it and HV T are sh ow n in Figure 2.2-2.

T o m inim iz e th e c orrosion of th e stainl ess steel in th e c ontainm ent during a L OCA, l ong-term p ost-L OCA p H c ontrol of th e IRW ST w ater is p rovided b y granul ar T SP, w h ic h is stored in b ask ets in th e HV T . T h e stainl ess steel b ask ets h ave a sol id top and b ottom w ith m esh sides to p rovide reasonab l e assuranc e of dissol ution w h en sub m erged in w ater.

As sh ow n in Figure 2.2-1, eac h q uadrant of th e IRW ST c ontains suc tion p ip ing and th e IRW ST sum p arrangem ents f or th e CS, SC, and SI p um p s. T h e suc tion p ip e is l oc ated w ith in th e IRW ST sum p p its.

An IRW ST sum p strainer c overs eac h IRW ST sum p p it in ac c ordanc e w ith th e guidanc e in NRC RG 1.82

( Ref erenc e [ 1-1] ) .

2.3 Design f or Prevention of Degraded Emergency Core Cooling System Perf ormance

1) L oc ation of HV T trash rac k T h ere are f our entranc es to th e HV T . T w o entranc es are l oc ated in th e side w al l of th e HV T w ith in sec ondary sh iel d w al l . T w o entranc es are l oc ated f ac ing th e op ening in th e sh iel d w al l . A vertic al trash rac k is l oc ated at eac h entranc e to HV T . Siz e of eac h HV T trash rac k l oc ated in th e 2 2 side w al l of th e HV T is 0.91 m x 2.29 m ( 3 f t x 7 f t 6 inc h ) , w h ic h rep resents 2.09 m ( 22.5 f t ) of sc reen surf ac e. In addition, th e siz e of eac h HV T trash rac k s f ac ing th e op ening in th e sh iel d 2 2 w al l is 2.92 m x 2.29 m ( 9 f t 7 in x 7 f t 6 inc h ) , w h ic h rep resents 6.68 m ( 71.85 f t ) . T h e HV T trash rac k s p revent deb ris p artic l es l arger th an 38.1 m m ( 1.5 inc h ) f rom entering th e HV T .

How ever, sm al l er deb ris p artic l es m ay enter th e HV T , b ut p artic l es w ith h igh density and insuf f ic ient h y drody nam ic f orc e ac ting on th em sink to th e b ottom of th e HV T . T h e rem aining p artic l es are entrained in th e f l ow to th e sp il l w ay s th at interc onnec t to th e HV T and th e IRW ST .

2) L oc ation of IRW ST sum p strainer Fol l ow ing an ac c ident, w ater introduc ed into c ontainm ent drains to th e HV T . T h e HV T trash rac k p revents l arger deb ris f rom entering th e HV T . T h e w ater th en travel s into th e IRW ST th rough th e IRW ST sp il l w ay s. T h e IRW ST sp il l w ay s are l oc ated at suf f ic ientl y h igh l oc ation to assure th at m uc h of th e h igh er-density deb ris settl es to th e b ottom of th e HV T . IRW ST sum p strainers are not instal l ed in th ese sp il l w ay s to assure th at th e f l ow f rom HV T to IRW ST is not interrup ted.

T h is w ater goes into th e SIS suc tion l ine th rough IRW ST sum p strainers. T h e f ine deb ris th at is introduc ed into th e IRW ST is p revented f rom entering th e SIS suc tion p ip e b y f our IRW ST sum p strainers. T h ese strainers h ave th e c ap ab il ity of rem oving p artic l es greater th an 2.38 m m ( 0.094 inc h ) in diam eter. T h e IRW ST sum p strainers are th e f inal b arrier to deb ris b ef ore th e ECCS and CSS suc tion l ines. It is ex p ec ted th at th e strainers h ave c ap ab il ity adeq uatel y to b l oc k any am ount of deb ris ( insul ation, c oating, and l atent deb ris) w ith out degrading ECCS and CSS p erf orm anc e.

KEPCO & KHNP 3

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3

3) L oc ation of engineered saf ety f eatures ( ESF) p um p suc tion T o m eet th e m ul ti-sum p req uirem ent of NRC RG 1.82 ( Ref erenc e [ 1-1] ) , th e general p l ant arrangem ent sep arates redundant trains of th e CSS, SCS, and SIS. T h is resul ts in an arrangem ent of tw o SI p um p s, one CS p um p and one SC p um p in eac h division. W ith in eac h division, th e tw o SI trains ( and eac h CS/ SC train) are sep arated b y a q uadrant w al l to isol ate th e trains f rom eac h oth er to th e p rac tic al l y m ax im um ex tent. Eac h of th e f our SI p um p s h as its ow n suc tion c onnec tion to th e IRW ST and eac h of th e tw o CS p um p s and tw o SC p um p s sh ares one of th ese f our c onnec tions.

2.4 IRWST Sump Strainer Fol l ow ing an ac c ident, w ater introduc ed into c ontainm ent drains to th e HV T . Any deb ris in th e c ontainm ent c oul d b e transp orted to th e HV T w ith th is f l uid. Deb ris b igger th an 38.1 m m ( 1.5 inc h ) in diam eter is p revented f rom entering th e HV T b y a vertic al HV T trash rac k at th e entranc e to th e HV T ( see Figure 2.2-2) . A trenc h at th e b ase of th e HV T trash rac k p revents any h igh -density deb ris sw ep t al ong th e f l oor b y f l uid f l ow tow ard th e HV T f rom reac h ing th e HV T trash rac k . T h e vertic al orientation of th e HV T trash rac k h el p s im p ede th e dep osition of deb ris b uil dup on th e IRW ST sum p strainer surf ac e.

Partic l es th at are sm al l er th an th e HV T trash rac k m esh enter th e HV T .

High -density deb ris th at enters th rough th e HV T trash rac k ac c um ul ates in th e b ottom of th e HV T . T h e IRW ST sp il l w ay s are l oc ated at a h igh el evation to p rovide reasonab l e assuranc e th at m uc h of th e h igh er density deb ris ( and deb ris th at tends to sink sl ow l y ) settl es to th e b ottom of th e HV T b ef ore sp il l ing over into th e IRW ST . Deb ris th at rem ains in susp ension m ak es its w ay to th e IRW ST sp il l w ay s. T h e sp il l w ay s are sh ow n in Figure 2.2-2.

T h e f ine deb ris introduc ed into th e IRW ST is p revented f rom entering th e p um p suc tion b y th e IRW ST sum p strainers as sh ow n in Figure 2.4-1. T h e IRW ST strainer h ol e diam eter is l ess th an 2.38 m m ( 0.094 inc h ) . T h e strainer design inc l udes redundanc y , a l arge surf ac e area to ac c ount f or p otential deb ris b l oc k age and m aintain saf ety p erf orm anc e, c orrosion resistanc e, and a strainer h ol e siz e to m inim iz e dow nstream ef f ec ts. T h e strainer is c om p osed of tub ul ar c artridges th at al l ow f l ex ib il ity in th e f inal strainer siz e. T h e IRW ST sum p strainers are m ounted on f our sum p p its w ith ac c ess th at al l ow s insp ec tion of th e sum p p it and inl et suc tion p ip e. T h e f inal strainer siz e ( surf ac e area) is p resented in Sub sec tion 3.5.2. Detail ed draw ings of th e tub ul ar strainer c artridge are p resented in Figure 2.4-2 and 2.4-3.

2.5 Insulation T h e insul ation ap p l ied to eq uip m ent and p ip es in th e c ontainm ent of th e APR1400 is as f ol l ow s:

1) Eq uip m ent Ref l ec tive m etal insul ation ( RM I) is ap p l ied to th e reac tor c ool ant p um p s ( RCP) , th e steam generators ( SG) , p ressuriz er ( PZ R) , l etdow n h eat ex c h anger, regenerative h eat ex c h anger, reac tor drain tank , and th e RV in th e areas th at h ave l arge am ount of insul ation p otential l y sub j ec ted to j et im p ingem ent f rom a h igh -energy l ine b reak ( HEL B ) .

No oth er eq uip m ent inside c ontainm ent is insul ated. In addition, h eating, ventil ation, and air c onditioning sy stem w ith in th e z one of inf l uenc e ( Z OI) is not req uired to h ave insul ation.

2) Pip e l ines KEPCO & KHNP 4

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 RM I is ap p l ied to al l p ip es inside th e c ontainm ent f or h eat c onservation, p ersonal p rotec tion, and anti-sw eet. Partic ul ate insul ations f or eq uip m ent and p ip e are not used in th e APR1400.

2.6 Coatings T h e c oating on struc tures, sy stem , and c om p onents w ith in c ontainm ent sh al l use onl y q ual if ied c oating ty p e w h ic h is q ual if ied and ac c ep tab l e c oating sy stem in a DB A. No unq ual if ied c oatings are to b e used inside c ontainm ent.

T h e c riteria f or c oating are addressed in NRC RG 1.54, Rev.2, Servic e L evel I, II, and III Protec tive Coatings Ap p l ied to Nuc l ear Pow er Pl ants ( Ref erenc e [ 2-1] ) and AST M D 3911-08 ( Ref erenc e [ 2-2] ) ,

Standard T est M eth od f or Eval uating Coatings U sed in L igh t-W ater Nuc l ear Pow er Pl ants at Sim ul ated Design B asis Ac c ident ( DB A) Conditions . Coatings are eval uated w ith c onsideration of th e c oating ty p e, c ondition assessm ent p rogram , generation assum p tion, assum ed c h arac teristic s, transp ort assum p tion, and h ead l oss testing in ac c ordanc e w ith " NRC Staf f Review Guidanc e Regarding Generic L etter 2004-02 Cl osure in th e Area of Coatings Eval uation," Enc l osure 2 to Revised Guidanc e f or Review of Final L ic ensee Resp onses to Generic L etter 2004-02 ( Ref erenc e [ 2-3] ) . T h ese eval uations are desc rib ed in th e p ertinent sec tions of th is rep ort and DCD ( Ref erenc e [ 3-1] ) . No ex c ep tion is tak en w ith regard to th e guidanc e.

KEPCO & KHNP 5

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 2.2-1 Plan V iew of IRWST KEPCO & KHNP 6

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 2.2-2 IRWST Sump Pit Elevation V iew KEPCO & KHNP 7

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 2.4-1 IRWST Sump Strainer KEPCO & KHNP 8

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 2.4-2 IRWST Sump Strainer Draw ing (Isometric V iew )

KEPCO & KHNP 9

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 2.4-3 IRWST Sump Strainer Draw ing (T op and Section V iew s)

KEPCO & KHNP 10

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3 EVALUATION OF IRWST SUMP STRAINER PERFORMANCE 3.1 Break Selection T h e in-c ontainm ent ref uel ing w ater storage tank ( IRW ST ) sum p s are vul nerab l e to deb ris b l oc k age onl y w h en th e sum p s are ac tive. T h e anal y sis th eref ore req uires an understanding of th e ac c ident p rogression to identif y th e ex tent of a h igh -energy l ine b reak ( HEL B ) to b e eval uated f or th e p otential to generate deb ris. T h e ac c ident anal y sis and op erational p roc edures are review ed to determ ine th e sc enarios th at req uire th e em ergenc y c ore c ool ing sy stem ( ECCS) and c ontainm ent sp ray sy stem ( CSS) to tak e suc tion f rom th e IRW ST sum p s. T h e review identif ies th e h igh -energy p ip ing sy stem s th at are eval uated f or a p ostul ated HEL B and assoc iated deb ris generation.

3.1.1 Accident Scenarios T h e design b asis ac c idents ( DB As) th at req uire engineered saf ety f eatures ( ESF) sy stem ac tion are sh ow n in T ab l e 7.3-2 of th e Design Control Doc um ent ( DCD) ( Ref erenc e [ 3-1] ) . T h ese DB As resul t in f ul l ESF initiation, w h ic h inc l udes th e initiation of f our saf ety inj ec tion p um p s ( SIPs) and tw o c ontainm ent sp ray p um p s ( CSPs) . Sh utdow n c ool ing p um p ( SCP) m ay b e initiated w h en th e CSP is not avail ab l e.

T h e design b asis ac c idents th at resul t in deb ris generation are:

1) L arge b reak l oss-of -c ool ant ac c ident ( L B L OCA)

Sub sec tion 6.3.1 of th e DCD ( Ref erenc e [ 3-1] ) c l assif ies L B L OCAs as a rup ture of th e reac tor 2 2 c ool ant p ressure b oundary w ith a total c ross-sec tional area l arger th an 0.046 m ( 0.5 f t ) ( ID 8 inc h p ip e) .

T h e p ip ing draw ings assoc iated w ith th e reac tor c ool ant sy stem ( RCS) are review ed to identif y th e l ines direc tl y attac h ed to th e RCS. High -energy l ines are l isted in T ab l e 3.6-1 of th e DCD

( Ref erenc e [ 3-1] ) . T h e ap p l ic ab l e L OCA b oundary is l oc ated w ith in th e sec ondary sh iel d w al l . It is c onc l uded, th eref ore, th at L OCAs outside th e sec ondary sh iel d w al l are not inc l uded in th e l ic ensing b asis, are not eval uated f or deb ris generation, and do not l ead to IRW ST sum p rec irc ul ation.

T h e design b asis L OCA is b ased on a p ostul ated doub l e-ended c ol d l eg ( CL ) ( ID 30 inc h es) guil l otine b reak on th e reac tor c ool ant p um p ( RCP) disc h arge l ine. From a deb ris generation p ersp ec tive, h ow ever, th e h ot l eg ( HL ) and c rossover l egs are l arger in diam eter ( ID 42 inc h es) ,

w h ic h inc reases th e z one of inf l uenc e ( Z OI) and al so inc reases th e p otential f or deb ris generation sinc e b reak Z OIs m ay ex tend to adj ac ent l oop s.

Six sep arate L B L OCAs are assessed to identif y th e b reak w ith th e p otential to generate th e l argest q uantity of deb ris. T h e b reak l oc ations are as f ol l ow s:

( a) 30 inc h RCS CL (b ) 42 inc h RCS HL steam generator ( SG) noz z l es (c ) 12 inc h p ressuriz er ( PZ R) surge l ine

( d) 16 inc h SCP Inl et l ines

( e) 12 inc h direc t vessel inj ec tion ( DV I) l ines (f) 12 inc h saf ety inj ec tion tank ( SIT ) inj ec tion l ines

2) Sm al l b reak l oss-of -c ool ant ac c ident ( SB L OCA)

KEPCO & KHNP 11

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 An SB L OCA is c l assif ied as a rup ture of th e reac tor c ool ant p ressure b oundary w ith a total c ross-2 2 sec tional area l ess th an 0.046 m ( 0.5 f t ) in w h ic h th e norm al l y op erating c h arging sy stem f l ow is not suf f ic ient to sustain th e PZ R l evel and p ressure. Sinc e SB L OCAs m ay not b e isol ated, th ey m ust b e c onsidered f or deb ris generation b ec ause m any c oul d l ead to IRW ST sum p rec irc ul ation.

Ac c ording to NEI 04-07 ( Ref erenc e [ 3-2] ) , onl y SB L OCA l ines w ith 2 inc h es and l arger are inc l uded in th e eval uation up to th e f irst isol ation p oint.

High -energy l ines are l isted in T ab l e 3.6-1 of th e DCD ( Ref erenc e [ 3-1] ) . T h e ap p l ic ab l e L OCA b oundary is l oc ated w ith in th e sec ondary sh iel d w al l . It is c onc l uded, th eref ore, th at L OCAs outside th e sec ondary sh iel d w al l are not inc l uded in th e l ic ensing b asis, are not eval uated f or deb ris generation, and do not l ead to IRW ST sum p rec irc ul ation.

SB L OCAs are assessed to identif y th e b reak w ith th e p otential to generate th e l argest q uantity of deb ris. T h e b reak l oc ations are as f ol l ow s:

( a) 7.75 inc h p il ot op erated saf ety rel ief val ve ( POSRV ) l ines (b ) 3 inc h c h arging l ines (c ) 4 inc h PZ R sp ray l ines

3) Oth er HEL B sc enarios W h il e a L OCA is c onsidered th e m ost l ik el y ty p e of a deb ris generating HEL B l eading to IRW ST sum p rec irc ul ation, oth er HEL B sc enarios are eval uated to determ ine w h eth er th ese b reak s c oul d resul t in deb ris generation f ol l ow ed b y th e need f or ECCS rec irc ul ation as a m eans of l ong-term c ore c ool ing ( L T CC) . As l ong as th e RCS rem ains intac t, th e intent in p ressuriz ed w ater reac tor

( PW R) design is to p rovide dec ay h eat rem oval via th e SG until th e p l ant c an b e c ool ed dow n, dep ressuriz ed, and p l ac ed on th e sh utdow n c ool ing sy stem ( SCS) . B ased on th e estab l ish m ent of dec ay h eat rem oval via th e SGs, it c an b e stated th at th e ECCS f l ow th rough th e c ore is not nec essary f or l ong-term dec ay h eat rem oval . T h eref ore, th e anal y sis of th e ef f ec ts of deb ris generation f rom th ese sc enarios on ECCS rec irc ul ation p erf orm anc e is not nec essary .

How ever, th e m ain steam l ine b reak ( M SL B ) is inc l uded in th e deb ris generation sinc e SIP and CSP op erations are initiated up on saf ety inj ec tion ac tuation signal ( SIAS) and c ontainm ent sp ray ac tuation signal ( CSAS) af ter an M SL B , as sh ow n in T ab l e 7.3-2 of th e DCD ( Ref erenc e [ 3-1] ) .

B ased on th e ac c ident sc enarios 1) , 2) , and 3) as desc rib ed ab ove, th e p ip es c onsidered to b e p ostul ated b reak p oints f or an eval uation of sum p strainer p erf orm anc e are l isted in T ab l e 3.1-1.

3.1.2 Selection of the Postulated Break Location T h e p ostul ated b reak l oc ation is sel ec ted c onsidering th e siz e and l oc ation of HEL B s th at p roduc e deb ris and p otential l y c h al l enge th e p erf orm anc e of th e IRW ST sum p strainers. Sinc e th e b reak l oc ation is not k now n p rior to th e eval uation, th e b reak sel ec tion p roc ess req uires eval uating a num b er of b reak l oc ations to identif y th e l oc ation th at is l ik el y to p resent th e greatest c h al l enge to p ost-ac c ident sum p p erf orm anc e.

T h e deb ris inventory and transp ort p ath are b oth c onsidered.

T h e sel ec tion of th e p ostul ated b reak l oc ation is b ased on th e p ip e b reak siz es and l oc ations th at are p rovided in ac c ident anal y ses and op erational p roc edures th at req uire th e ECCS and CSS to tak e suc tion f rom th e IRW ST sum p s and ac c ording to th e guidanc e in NEI 04-07 ( Ref erenc e [ 3-2] ) and th e Saf ety Eval uation ( SE) of NEI 04-07 ( Ref erenc e [ 3-3] ) .

Sub sec tions 3.3.4 and 4.2.1 of NEI 04-07 rec om m end th at a suf f ic ient num b er of b reak s in eac h h igh -

KEPCO & KHNP 12

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 p ressure sy stem th at rel y on rec irc ul ation b e c onsidered to ensure th at th e b reak s th at b ound variations in deb ris generation b y siz e, q uantity , and ty p e of deb ris are identif ied.

T h e f ol l ow ing b reak l oc ation c riteria are c onsidered.

1) Pip e b reak in th e RCS or m ain steam sy stem / f eedw ater sy stem ( M S/ FW ) w ith th e l argest p otential f or p roduc ing deb ris

2) L argest b reak w ith tw o or m ore ty p es of deb ris

3) B reak s in th e m ost direc t p ath to th e sum p

4) L arge b reak w ith th e p otential f or p roduc ing th e h igh est of p artic ul ate deb ris to insul ation b y w eigh t

5) B reak s th at generate th in b ed - h igh p artic ul ate w ith 1/ 8 inc h f ib er Ac c ording to Sub sec tion 3.3.4.1, item 7 in th e SE of NEI 04-07 ( Ref erenc e [ 3-3] ) , p ip ing w ith a diam eter of l ess th an 2 inc h es c an b e ex c l uded w h en determ ining l im iting b reak c onditions.

For b reak c riteria 1) and 2) , a b reak of th e RCS or M S/ FW p ip ing c onnec ted to m aj or eq uip m ent generates m ax im um deb ris l oads ( insul ation, c oating, and oth er deb ris sourc es) b ec ause th e RCS or M S/ FW p ip ing

( RCS h ot l eg l ine ( 42 inc h ) , RCS c ol d l eg l ine ( 30 inc h ) , and M ain Steam l ine ( 30.907 inc h ) ) h ave th e l argest p ip e diam eters resul ting in th e l argest Z OIs f or deb ris generation. In addition, RCS p ip ing generates th e m ax im um num b er of ty p es of deb ris inc l uding insul ation, c oating, and oth er deb ris sourc es.

An eval uation of b reak c riterion 3) is not nec essary b ec ause th ere are no b reak s w ith a h igh -energy l ine w ith in th e IRW ST , and f our strainers and sum p s are l oc ated inside th e IRW ST c om p artm ent, w h ic h is p rotec ted f rom th e h igh -energy p ip ing sy stem in th e c ontainm ent.

B reak c riterion 4) does not ap p l y to th e APR1400 b ec ause onl y RM I is used on p ip ing and p artic ul ate insul ation is not used.

For an eval uation of th e th in-b ed ef f ec t ( T B E) assoc iated w ith th e b reak c riterion 5) , it is w el l k now n th at h ead l oss due to T B E dep ends on th e am ount of p artic ul ate deb ris. As desc rib ed ab ove, th e w orst c ase of p artic ul ate deb ris generation is c onsidered.

B ased on th e ab ove eval uation, th e w orst c ase b reak l oc ation f or deb ris generation is a b reak of RCS or M S/ FW sy stem p ip ing l oc ated in one SG c om p artm ent ( RCS h ot l eg l ine ( 42 inc h ) , RCS c ol d l eg l ine ( 30 inc h ) , and m ain steam l ine ( 30.907 inc h ) ) .

B ased on th e guidanc e in Ref erenc e [ 3-3] , th e p ostul ated b reak l oc ation in th e APR1400 is sel ec ted to resul t in m ax im um deb ris l oads and variety of deb ris ty p es.

KEPCO & KHNP 13

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.2 Deb ris G eneration T h e sourc es of deb ris in th e APR1400 are insul ation, c oating, and l atent deb ris. RM I and c oating deb ris are c onsidered as th e p otential deb ris sourc es f ol l ow ing a HEL B .

As desc rib ed in Sub sec tion 3.1.2, th e w orst c ases of deb ris generation are th e RCS h ot l eg l ine ( 42 inc h )

b reak , RCS c ol d l eg l ine ( 30 inc h ) b reak , and m ain steam l ine ( 30.907 inc h ) b reak . A sp h eric al Z OI is used to estim ate th e vol um e of generated deb ris. Figures 3.2-1 th rough 3.2-3 sh ow a sec tional view of th e Z OI f or eac h b reak l oc ation.

For l atent deb ris, th e 90.72 k g ( 200 l b m ) is assum ed as l atent deb ris in ac c ordanc e w ith NEI 04-07

( Ref erenc e [ 3-2] ) .

T h e detail ed eval uation m eth odol ogy and resul ts of deb ris generation used f or th e th ree l im iting b reak are desc rib ed in Ap p endix B . From th e eval uation resul ts in Ap p endix B , th e am ount of insul ation, c oating, and l atent deb ris assum ed f or th e th ree b reak l oc ations is sum m ariz ed in T ab l e 3.2-1.

As sh ow n in T ab l e 3.2-1, th e j unc tion of th e RCS HL p ip e ( 42 inc h ) and SG is sel ec ted as th e p ostul ated b reak l oc ation. T h is b reak l oc ation is reasonab l e b ec ause th e SGs h ave a l arger vol um e of insul ation th an RCS p ip ing and m ost of th e p rim ary sy stem p ip ing is l oc ated in th is SG c om p artm ent. T h e l arger am ount of insul ation p resents and th e greater vol um e of deb ris are transp orted to th e IRW ST sum p strainer. T h is resul ts in th e m ax im um h ead l oss ac ross th e IRW ST sum p strainer.

3.3 Deb ris Characteristics T h ree p otential sourc es of deb ris are eval uated f or th eir im p ac ts on th e APR1400 rec irc ul ation f l ow p ath and L T CC. T h ese deb ris sourc es are as f ol l ow s:

1) Z OI c oatings - Coatings in th e Z OI of a L OCA are assum ed to f ail as f ines ( sm al l p artic l es) and to b e transp orted to th e strainer.

2) L atent deb ris - L atent deb ris is dirt, dust, l int, and oth er m isc el l aneous m aterial s th at m ay b e p resent inside c ontainm ent b ef ore th e initiation of a L OCA.

3) Post-ac c ident c h em ic al ef f ec ts - Post-ac c ident c h em ic al ef f ec ts are th e resul t of c ontainm ent sum p f l uid reac ting c h em ic al l y w ith m aterial s inside c ontainm ent and p roduc ing c h em ic al p rec ip itates.

NEI 04-07 indic ates th at 90.72 k g ( 200 l b m ) of l atent deb ris w ith a 15% / 85% ( f ib er to p artic ul ate) sp il l ed to determ ine l atent deb ris l oads. How ever, th e APR1400 design assum es th at 90.72 k g ( 200 l b m ) of l atent deb ris w ith a 7.5% / 92.5% ( f ib er to p artic ul ate) sp il l ed to determ ine l atent deb ris l oads, th at al l l atent f ib rous deb ris w ith in c ontainm ent is f ine, and th at th ere is no need to def ine f ib rous deb ris siz e.

Fib rous deb ris is c ategoriz ed in Ref erenc e [ 3-3] as f ol l ow s:

1) Fines th at easil y rem ain susp ended in w ater, even rel ativel y q uiesc ent w ater

2) Sm al l p iec e th at readil y sink s in h ot w ater and c an transp ort al ong th e f l oor w h en f l ow vel oc ity and p ool turb ul enc e are suf f ic ient

3) L arge p iec e th at readil y sink s in h ot w ater and c an transp ort al ong th e f l oor w h en vel oc ity and p ool turb ul enc e are suf f ic ient

4) Intac t deb ris th at readil y sink s in h ot w ater and c an transp ort al ong th e f l oor w h en vel oc ity and KEPCO & KHNP 14

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 p ool turb ul enc e are suf f ic ient T h eref ore, al l l atent f ib rous deb ris assum ed as f ines easil y rem ains susp ended in w ater ( even rel ativel y q uiesc ent w ater) and c ol l ec ts in th e sum p s.

NEI 04-07 ( Ref erenc e [ 3-2] ) guidanc e is 75% f ines and 25% l arge p iec es as th e siz e distrib ution of any ty p e of RM I inside a p ip e b reak Z OI. T h e eval uation of th e APR1400 design f ol l ow s th e guidanc e in NEI 04-07 ( Ref erenc e [ 3-2] ) of 75 p erc ent sm al l f ines and 25 p erc ent l arge p iec es as th e siz e distrib ution of any ty p e of RM I inside a p ip e b reak Z OI.

Sub sec tion 3.4.3.2 of NEI 04-07 ( Ref erenc e [ 3-2] ) desc rib es of th e deb ris siz e distrib utions th at h ave b een used in various studies and sp ec if ies a tw o-siz e distrib ution f or m aterial inside th e Z OI of a p ostul ated b reak f or th e eval uation. T h e tw o siz es are f ines ( < 4 inc h ) and l arge p iec es ( > 4 inc h ) . Fines are def ined as any m aterial th at c oul d transp ort th rough gratings, trash rac k s, and/ or radiol ogic al p rotec tion f enc es b y b l ow dow n, c ontainm ent sp ray s, or p ost-ac c ident p ool f l ow s. Fines are assum ed to b e th e b asic c onstituent of th e m aterial f or l atent deb ris ( f or f ib ers and p artic l es) , and c oatings ( in th e f orm of individual f ib ers, p artic l es, and p igm ents, resp ec tivel y ) . RM I deb ris is suf f ic ientl y dense and th e f l ow rates are al so suf f ic ientl y sm al l to p revent th e RM I deb ris f rom b eing transp orted to th e APR1400 strainer. RM I is c om p osed of th in l ay ers of stainl ess steel f oil . Stainl ess steel h as a density of 7.85 g/ c m 3 ( 490 Ib m / f t3) .

NEI 04-07 ( Ref erenc e [ 3-2] ) and th e SE f or NEI 04-07 ( Ref erenc e [ 3-3] ) indic ate th e f ol l ow ing c oating ef f ec ts:

1) Al l c oatings in th e Z OI w il l f ail .

2) Al l q ual if ied c oatings outside th e Z OI rem ain intac t unl ess dam aged or degraded.

3) Al l unq ual if ied c oatings in c ontainm ent w il l f ail .

Per Sub sec tion 3.4.3.2 of NEI 04-07 ( Ref erenc e [ 3-2] ) , al l q ual if ied c oatings w ith in th e Z OI are c onsidered m ( 0.394 m il ) . Al l c oating deb ris is susp ended and transp orted in th e rec irc ul ating w ater al ong w ith th e l atent deb ris to th e strainers. T h e APR1400 strainer is not susc ep tib l e to c oating deb ris in th e f orm of c h ip s sinc e c h ip s w il l settl e and not ac c um ul ate in suc h a w ay to b l oc k th e strainer ( suc h as in a p it c onf iguration) , and th e f ail ure c h arac teristic of inorganic z inc and ep ox y c oatings f rom industry ex p erienc e is erosion resul ting in very sm al l p artic ul ates f rom th e sub strate due to th e j et im p ingem ent.

T h e deb ris c h arac teristic s used in th e APR 1400 eval uation are p resented in T ab l es 3.3-1 and 3.3-2.

KEPCO & KHNP 15

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.4 Deb ris T ransport Deb ris transp ort q uantif ies deb ris th at transp orts to th e sum p strainer. T h e am ount of deb ris generation and th e c h arac teristic s of th e deb ris transp ort are used to determ ine deb ris ac c um ul ation.

T h e b l oc k age of th e strainers and its ef f ec t on th e net p ositive suc tion h ead ( NPSH) of th e p um p s are c onsidered c onservativel y w h en th e ac c um ul ation h as reac h ed its m ax im um .

In ac c ordanc e w ith th e guidanc e p rovided in Sub sec tion 3.6.1 of NEI 04-07 ( Ref erenc e [ 3-2] ) , th e f ol l ow ing f our m aj or deb ris transp ort m odes are c onsidered.

1) B l ow dow n transp ort - Horiz ontal and vertic al transp ort of deb ris b y th e b reak j et. Al l deb ris b y th e b reak j et is transp orted to th e c ontainm ent f l oor. No deb ris is transp orted up w ards to th e c ontainm ent dom e.

2) W ash dow n ( c ontainm ent sp ray ) transp ort - V ertic al transp ort of deb ris b y th e c ontainm ent sp ray s/ b reak f l ow . Sinc e al l deb ris is m odel ed as transp orting to th e c ontainm ent f l oor during b l ow dow n, th ere is no w ash dow n transp ort.

3) Pool f il l -up transp ort - Horiz ontal transp ort of th e deb ris b y b reak and CS f l ow s to ac tive and inac tive areas of th e b asem ent p ool . Al l deb ris are transp orted out of th e SG D-rings to th e h ol dup vol um e tank ( HV T ) and assum ed to b e transp orted to th e IRW ST . T h e l arge p iec e of RM I insul ation is not transp orted to IRW ST sum p strainers l oc ated in th e IRW ST b ec ause of suf f ic ient density ( T ab l e 3.3-2) and sl ow f l ow rates. No transp ort to inac tive vol um es is m odel ed.

4) Rec irc ul ation transp ort - Horiz ontal transp ort of th e deb ris in th e ac tive p ortions of th e b asem ent p ool b y th e rec irc ul ation f l ow th rough th e ECCS/ CSS. Al l l atent deb ris and f ail ed c oating are c onservativel y assum ed to b e c ol l ec ted in th e HV T and transp orted to th e IRW ST sum p strainers b y rec irc ul ating w ater. T h e onl y sm al l am ount of RM I deb ris is assum ed to b e transp orted to th e HV T and th e IRW ST in th e APR1400. T h e sum p ap p roac h f l ow vel oc ity ( i.e., 0.088 m / s ( 0.29 f t/ s) ) at th e IRW ST is l ow er th an th e term inal settl ing vel oc ity ( i.e., 0.113 m / s ( 0.37 f t/ s) ) and l if t over c urb vel oc ity ( i.e., 0.256 m / s ( 0.84 f t/ s) ) of th e RM I f ine deb ris addressed in T ab l e 4-2 of NEI 04-07 ( Ref erenc e [ 3-2] ) . T h eref ore, RM I deb ris transp orted in th e IRW ST settl es on th e IW RST f l oor around th e sum p and does not rise to th e strainer surf ac e.

Al l p artic ul ate and c oating deb ris is assum ed to b e f ine enough to rem ain in susp ension due to turb ul enc e and to b e transp orted to th e IRW ST sum p strainers. T h is assum p tion p rovides th e m ost c onservative up p er l im it f or th e deb ris transp ort eval uation and inc l udes th e deb ris b reak ing dow n to its m inim um siz e initial l y so no f urth er p artic l e siz e reduc tion oc c urs during transp ort.

L atent deb ris is c ategoriz ed as f ib er and p artic ul ates and is assum ed to b e unif orm l y distrib uted. Al l l atent f ib er is assum ed to h ave th e sam e f ib er diam eter as NU KON insul ation.

T h e APR1400 design h as f our ECCS/ CS trains w ith an indep endent strainer f or eac h train. T h e design req uires a m inim um of th ree trains in op eration assum ing th at th e f ourth train h as a singl e f ail ure.

T h eref ore, transp orted deb ris in th e IRW ST is assum ed to b e distrib uted to th ree sum p s. How ever, th e APR1400 design assum es th at al l of b reak -generated c oating, l atent deb ris, and c h em ic al p rec ip itates are transp orted direc tl y to a singl e sum p f or c onservatism f or th e strainer h ead l oss eval uation and th e NPSH eval uation. For th e b y p ass deb ris f rac tion, th e num b er of avail ab l e sum p s m ax im iz es th e am ount of b y p ass deb ris ( i.e., assum es f our op erating sum p s) . No c redit is tak en f or deb ris settl em ent on th e f l oor or entrap m ent in inef f ec tive p ool .

KEPCO & KHNP 16

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.5 Deb ris H ead Loss 3.5.1 IRWST Sump Strainer Design Conditions T h e APR1400 uses RM I as th e p rim ary insul ation sy stem and does not use f ib rous or oth er p rob l em atic m aterial s inside c ontainm ent. T h e onl y sourc e of f ib rous insul ation is th eref ore l atent deb ris. T h e ty p es and q uantities of deb ris are l im ited to l atent f ib er and p artic ul ate, c oatings, and c h em ic al ef f ec ts.

T h e design of th e strainer is b ased on th e f ol l ow ing:

1) Fl ow c ondition

( a) Fl ow rate ( L / m in / gp m ) ............................................................................. 25,211 / 6,660

( b ) Fl uid tem p erature ( ° C / ° F) ........................................................................ 60 - 121.1 / 140 - 250

2) Deb ris q uantity 3 3

( a) Ep ox y c oating ( m / f t ) ............................................................................. 0 - 0.0878 / 0 - 3.10 (b ) L atent f ib er ( k g / l b m ) ................................................................................ 6.80 / 15 (c ) L atent p artic ul ate ( k g / l b m ) ...................................................................... 83.91 / 185

3) Ch em ic al deb ris w ith p otential to c ause c h em ic al ef f ec ts ( T ab l e 3.8-2) 2 2

( a) Sub m erged c onc rete ( m / f t ) .................................................................. 193.89 / 2,087 2 2 (b ) U nsub m erged c onc rete ( m / f t ) .............................................................. 674.20 / 7,257 2 2 (c ) Sub m erged al um inum ( m / f t ) ............................................................ .... 0 2 2

( d) U nsub m erged al um inum ( m / f t ) ............................................................ 216.09 / 2,326 3.5.2 IRWST Sump Strainer Siz ing T h e strainer eval uation m eth odol ogy is b ased on th e integration of an anal y tic al determ ination of th e c l ean strainer h ead l oss and th e resul ts of a p rototy p ic al deb ris h ead l oss test. Given th e dif f ic ul ties w ith anal y tic al p redic tions of deb ris h ead l oss w ith c h em ic al p rec ip itates, sc al ed testing p rovides th e b est m easurem ent of strainer p erf orm anc e under th ese deb ris c onditions. T h e strainer testing is p erf orm ed in ac c ordanc e w ith th e h ead l oss testing guidanc e in th e NRC Staf f Review Guidanc e Regarding Generic L etter 2004-02, Cl osure in th e Area of Strainer Head L oss and V ortex ing ( Ref erenc e [ 3-4] ) . T h e detail ed test p l an is p rovided in APR1400 IRW ST ECCS Sum p Strainer Prototy p e Hy draul ic Q ual if ic ation T est Pl an ( Ref erenc e [ 3-5] ) and th e test resul t is p rovided in Ap p endix C of th is rep ort.

2 2 V al idation of th e f inal strainer siz ing of 55.74 m ( 600 f t ) is ac c om p l ish ed b y testing th e p rototy p e strainers w ith f l ow s and sc al ed deb ris l oads f or th e design c onditions and ex trap ol ating th e resul ts to th e design b asis tem p erature range. A detail ed view of th e sum p strainer is p rovided in Figure 3.5-1.

3.5.3 IRWST Sump Strainer H ead Loss 3.5.3.1 Clean Strainer H ead Loss T h e strainer is designed to f it over th e top of th e IRW ST sum p p its w ith f l ow direc tl y into th e p it to m inim iz e c l ean strainer h ead l osses. As a c al c ul ation resul t of th e c l ean strainer h ead l osses, 7.62 c m -w ater ( 0.25 f t-w ater) f or a tem p erature of 60 ° C ( 140 ° F) is determ ined. Given th e l ow h ead l oss of th e c l ean strainer in th e testing, th is c al c ul ated h ead l oss is c onservativel y ap p l ied to th e h igh er tem p eratures. It is c onservative sinc e th e c l ean h ead l oss is a direc t f unc tion of f l uid density and th e density of th e f l uid dec reases w ith an inc rease in tem p erature.

KEPCO & KHNP 17

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.5.3.2 Deb ris H ead Loss T h e ob j ec tive of th e p rototy p e deb ris h ead l oss tests is to devel op ex p erim ental h ead l oss data assoc iated w ith th e sp ec if ied deb ris l oadings. Fl ow sw eep s are c onduc ted to ob tain additional h ead l oss data as a f unc tion of f l ow rate ( i.e., vel oc ity ) f or p otential use in th e tem p erature c orrec tion anal y sis. T h e testing inc l udes m easurem ents of dif f erential p ressure ac ross th e strainer, f l uid tem p erature, and p um p f l ow rate f or th e deb ris m ix tures identif ied in th e test m atrix . T h e testing is designed to dem onstrate th at th e h ead l oss assoc iated w ith th e strainer is ac c ep tab l e f or th e design deb ris l oading or to identif y th e m ax im um al l ow ab l e deb ris l oading th at resul ts in ac c ep tab l e h ead l oss.

T w o h ead l oss tests are p erf orm ed. T h e dif f erenc e b etw een tests is th e c h ange in ef f ec tive surf ac e area 2

of th e strainer to ac c ount f or l ab el s and tags. T h e f irst test uses an ef f ec tive surf ac e area of 55.74 m 2 2 2

( 600 f t ) , and th e sec ond test uses an ef f ec tive surf ac e area of 46.45 m ( 500 f t ) . T h ese tw o tests are ac c om p l ish ed b y inc reasing th e test f l ow rate f or th e sec ond test f rom 3,157 L / m in ( 834 gp m ) to 3,785 L / m in ( 1,000) gp m and inc reasing th e m ass of deb ris p er sq uare f oot. Additional l y as a resul t of th e NRC s w itnessing th e f irst test, th e sec ond test uses f ib er p rep ared to h eavil y f avor Cl ass 1 and 2 f ib er c l asses.

T h e detail s of th e testing p rogram and sel ec tion of th e p rototy p e are disc ussed in Ref erenc e [ 3-5] and th e test resul t is p rovided in Ap p endix C of th is rep ort.

2 2 T h e m ax im um h ead l oss f or th e 46.45 m ( 500 f t ) ef f ec tive strainer area w ith th e m ax im um deb ris l oad is 24.69 c m -w ater ( 0.81 f t-w ater) at th e design f l ow rate and inc l udes a c l ean sc reen c om p onent of 15.85 c m -w ater ( 0.52 f t-w ater) . T h eref ore, th e deb ris onl y h ead l oss f or b oth tests is essential l y th e sam e at 8.84 c m -w ater ( 0.29 f t-w ater) . W h il e th e f l ow rates/ deb ris m ass p er unit area are sl igh tl y dif f erent, th e resul ts are nearl y identic al and rep eatab l e and c onsiderab l y l ess th an th e 60.96 c m -w ater ( 2 f t-w ater) al l ow ab l e h ead l oss. T h e resul ts are due to th e very l ow deb ris l oad th at is insuf f ic ient to c over th e sc reen c om p l etel y , sim il ar to th at of th e c l ean p l ant c riteria.

T h ese test resul ts are ex p erim ental l y m easured in a test f l uid at ap p rox im atel y 31.1 ° C ( 88 ° F) .

T h eref ore, it is c onservative to use th ese val ues at h igh er tem p eratures sinc e f l uid density and visc osity dec rease w ith inc reasing tem p erature.

3.5.3.3 T otal Strainer H ead Loss T h e p rototy p e deb ris h ead l oss test resul ts and c al c ul ated c l ean strainer h ead l oss are c om b ined to p rovide a total strainer h ead l oss th at is c om p ared to th e al l ow ab l e h ead l oss.

T h e total strainer h ead l oss val ue is th e sum of th e c l ean strainer h ead l oss and deb ris h ead l oss. T h is is c onservativel y c al c ul ated b y doub l e c ounting th e c l ean sc reen c om p onent using th e anal y tic al val ue and th e test val ue inh erent in th e m easure deb ris h ead l oss. T h eref ore, 7.62 c m -w ater ( 0.25 f t-w ater) p l us 24.69 c m -w ater ( 0.81 f t-w ater) eq ual s 32.31 c m -w ater ( 1.06 f t-w ater) at 60 ° C ( 140 ° F) . Conseq uentl y , th e resul t of a total strainer h ead l oss l ess th an th e al l ow ab l e h ead l oss val idates th e design.

KEPCO & KHNP 18

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.6 Net Positive Suction H ead NPSH is a m easure of th e f l uid energy at a p um p inl et. Req uired NPSH ( NPSHr) is th e m inim um f l uid energy , in ex c ess of th e vap or p ressure energy , req uired at th e p um p inl et to p revent c avitation f rom oc c urring inside th e p um p and to ob tain satisf ac tory op eration. NPSH is ty p ic al l y sp ec if ied b y th e p um p m anuf ac turer and is a f unc tion of th e p um p f l ow rate. Avail ab l e NPSH ( NPSHa) is th e f l uid energy avail ab l e at th e p um p inl et b ased on th e sy stem c onf iguration and op erating c onditions. T h e NPSH m argin ( NPSHm ) is th e dif f erenc e b etw een NPSHa and NPSHr and m ust b e greater th an z ero to p rec l ude p um p c avitation.

3.6.1 System Operation Figure 3.6-1 sh ow s th e sc h em atic f l ow diagram of th e ECCS. Em ergenc y c ore c ool ing is p rovided b y th e saf ety inj ec tion sy stem ( SIS) . T h e SIS c onsists of f our m ec h anic al l y sep arated trains, f our SIT s, and assoc iated val ves, p ip ing and instrum entation. Eac h SIP is norm al l y al igned w ith its ow n suc tion l ine f rom th e IRW ST and its ow n disc h arge l ine to a DV I noz z l e on th e reac tor vessel ( RV ) or th e DV I noz z l e/ h ot l eg. SI l ines 1 and 2 inj ec t th e b orated w ater to th e RCS th rough th e DV I noz z l es and SI l ines 3 and 4 inj ec t th e b orated w ater to th e DV I noz z l es or HL inj ec tion l ines during th e l ong-term m ode.

T h e SIS autom atic al l y goes into op eration up on indic ation th at a signif ic ant b reac h in th e RCS b oundary h as oc c urred. T h e SIPs are autom atic al l y initiated b y th e SIAS, and th e sh ort-term m ode of op eration is al so initiated up on an SIAS. An SIAS is p roduc ed up on tw o-out-of -f our c oinc ident l ow PZ R p ressure or a h igh c ontainm ent p ressure signal . Op erator ac tions are req uired to initiate th e l ong-term m ode.

Op erator ac tions dep end on b reak siz e, tim e into th e L OCA, and w h eth er th e L OCA h as b een isol ated.

T h e l ong-term m ode is m anual l y initiated at ap p rox im atel y 1 to 2 h ours p ost-L OCA w h en HL inj ec tion val ves in th e disc h arge p ip ing of SIPs 3 and 4 are op ened, and th e DV I f l ow p ath c ol d side val ves of SIPs 3 and 4 are c l osed. T h e DV I noz z l e f l ow p ath s of SIPs 1 and 2 rem ain op en. T h e c onf iguration of SIPs 3 and 4 inj ec ting into th e HL s and SIPs 1 and 2 inj ec ting into th eir resp ec tive DV I noz z l e p rovides c irc ul ation f l ow th rough th e c ore. For SB L OCAs, th e SIPs p rovide m ak eup f or sp il l age, w h il e th e RCS is c ool ed dow n and dep ressuriz ed to sh utdow n c ool ing ( SC) initiation c onditions using th e SG atm osp h eric dum p val ves and aux il iary f eedw ater sy stem .

T h e CSS c onsists of tw o 100% c ap ac ity trains, eac h of w h ic h h as tw o indep endent CSPs, tw o c ontainm ent sp ray h eat ex c h angers ( CSHX s) , tw o CS m ini-f l ow h eat ex c h angers, CS h eaders, and assoc iated val ves. Figure 3.6-2 sh ow s th e sc h em atic f l ow diagram of CSS.

T h e CSPs are autom atic al l y ac tuated b y an SIAS or a CSAS f rom th e ESF ac tuation sy stem . T h e CSAS is initiated b y a c oinc idenc e of tw o-out-of -f our h igh -h igh c ontainm ent p ressure signal s or tw o rem ote m anual signal s f rom th e c ontrol room or b y l oss of p ow er to tw o-out of -f our ac tuation l ogic c h annel s. T h e CSAS op ens th e CS h eader isol ation val ves to th e c ontainm ent.

Onc e th e CSPs are started and th e val ves are op ened, th e sp ray w ater f l ow s into th e CS h eaders. T h ese h eaders c ontain sp ray noz z l es th at b reak th e f l ow into sm al l drop l ets enh anc ing th e w ater' s c ool ing ef f ec t on th e c ontainm ent atm osp h ere. As th ese drop l ets f al l to th e c ontainm ent f l oor, th ey ab sorb h eat until th ey reac h th erm al eq uil ib rium w ith th e c ontainm ent. T h e units are designed to reduc e th e c ontainm ent atm osp h ere p ressure 24 h ours af ter an ac c ident to h al f of th e c al c ul ated p eak p ressure. T h e CSPs are f unc tional l y interc h angeab l e w ith th e SCPs w h en not req uired to p erf orm th eir req uisite design b asis f unc tion, assum ing a l oss of of f site p ow er ( L OOP) and singl e f ail ure. T h e CSPs c an b e used as a b ac k up to th e SCPs to p rovide residual h eat rem oval , and th e CSPs and th e CSHX s c an b e used as a b ac k up to th e SCPs and th e SC h eat ex c h angers to p rovide c ool ing of th e IRW ST .

T h e CSPs, SCPs, and SIPs are norm al l y al igned to th e IRW ST inside th e c ontainm ent. T h ese p um p s tak e suc tion direc tl y f rom th e IRW ST . Four IRW ST sum p strainers are instal l ed in th e IRW ST and eac h KEPCO & KHNP 19

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 strainer is f or one of th e f our trains.

T h e f l ow rates of th e SIP and CSP are sh ow n in T ab l e 3.6-1 and th ese val ues are used f or NPSH eval uation. T h e m ax im um f l ow rate f or th e SIP and CSP/ SCP are 4,675 L / m in ( 1,235 gp m ) and 20,536 L / m in ( 5,425 gp m ) resp ec tivel y . T h e SIP and CSP or SIP and SCP op erate sim ul taneousl y w h il e draw ing f rom th e sum p .

3.6.2 Availab le NPSH Calculation T h e c ontainm ent p ressure is assum ed to b e eq ual to th e initial c ontainm ent p ressure p rior to th e start of th e ac c ident ( f or sum p f l uid tem p eratures b el ow th e saturation tem p erature c orresp onding to th is c ontainm ent p ressure) . T h is m eth odol ogy c onf orm s w ith th e req uirem ents of NRC RG 1.1, " W ater Sourc es f or L ong-term Rec irc ul ation Cool ing Fol l ow ing a L oss-of -Cool ant Ac c ident" ( Ref erenc e [ 3-6] ) and RG 1.82 ( Ref erenc e [ 1-1] ) th at th e NPSHa b e eval uated w ith out c rediting any inc rease in p ressure resul ting f rom ac c ident c onditions at l ow tem p eratures. T h is ap p roac h ensures th at suf f ic ient c ontainm ent p ressure is avail ab l e under al l ac c ident c onditions and th at def ense-in-dep th is m aintained b y p reserving th e indep endenc e of sy stem s designed to p revent ac c idents and th ose designed to m itigate th e ef f ec ts of ac c idents. It is assum ed th at th e c ontainm ent p ressure rem ains c onstant at th e p re-ac c ident val ue c onsistent w ith NRC RG 1.82 and RG 1.1, f or sum p f l uid tem p eratures l ow er th an th e c orresp onding initial saturation vap or p ressure. For tem p eratures h igh er th an th is initial saturation p ressure c ondition, th e c ontainm ent p ressure is assum ed to b e eq ual to th e sum p f l uid vap or p ressure.

1) Assum p tions

( a) Singl e f ail ure Eac h of th e f our SIPs is p rovided w ith a sep arate suc tion l ine f rom th e IRW ST and a sep arate disc h arge l ine to one of f our DV I noz z l es. One SIP and assoc iated inj ec tion val ves in eac h train are p ow ered f rom th e indep endent em ergenc y p ow er sup p l y . T h is p rovides th e autom atic op eration of th ree trains of SIPs in th e unl ik el y event of a c onc urrent L OOP and th e f ail ure of an ac tive c om p onent, inc l uding a standb y generator. T h eref ore, a singl e f ail ure in any singl e train does not af f ec t f l ow rate th rough any oth er strainer or SI train.

T h e CSP and SCP c onsist of tw o trains and an IRW ST sum p strainer is instal l ed f or eac h train ( i.e., one IRW ST sum p strainer is instal l ed f or one CS p um p or f or one SC p um p ) . T h e m ost l im iting singl e f ail ure f or th e IRW ST sum p strainer is a singl e CSP or SCP f ail ure c aused b y th e f ail ure of an em ergenc y b us. T h eref ore, a singl e f ail ure in oth er trains does not af f ec t f l ow rate th rough th e IRW ST sum p strainer.

(b ) Containm ent p ressure For th e m inim um NPSHa c al c ul ation, no additional c ontainm ent p ressure is c redited ab ove th e initial c ontainm ent p ressure f or l ow sum p f l uid tem p eratures ( i.e., b el ow ap p rox im atel y 100 ° C ( 212 º F) . For h igh er sum p f l uid tem p eratures, th e c ontainm ent p ressure is assum ed to eq ual th e saturation p ressure c orresp onding to th e sum p w ater tem p erature.

During L OCA and p ost-L OCA c onditions f or th e APR1400, c ontainm ent p ressure al w ay s ex c eeds th e saturated vap or p ressure at th e IRW ST w ater tem p erature.

During a L OCA, m ass and energy are rel eased f rom th e p rim ary sy stem to b oth th e vap or p h ase ( c ontainm ent atm osp h ere) and to th e IRW ST ( l iq uid p h ase) inside th e c ontainm ent vol um e. Steam rel eased f rom th e p rim ary sy stem p ostul ated b reak m aintains th e c ontainm ent atm osp h ere at saturated c onditions during al m ost al l of th e L OCA transients.

M oreover, f l uid c ondensed b y p assive h eat sink s ( suc h as th e c ontainm ent sh el l l iner, KEPCO & KHNP 20

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 sup p orting struc tures and c onc rete) and th e CS is added to th e IRW ST . T h e c ondensed w ater entering th e IRW ST is at th e steam p artial p ressure in th e c ontainm ent atm osp h ere.

Af ter th e l ong-term op eration, th e IRW ST l iq uid tem p erature is strongl y af f ec ted b y th e l iq uid w ater c ondensed f rom th e atm osp h ere during th e CS op eration. T h e c ondensed w ater is al so saturated at th e steam p artial p ressure.

T h eref ore, a h igh er c ontainm ent p ressure p rovides c ondensed w ater at a h igh er tem p erature and h igh er IRW ST l iq uid tem p eratures. Sim il arl y , a l ow er c ontainm ent p ressure p rovides c ondensed w ater at l ow er tem p erature and a l ow er IRW ST l iq uid tem p erature. For th e p urp oses of th e NPSHa determ inations f or ECCS p um p s, th e APR1400 does not c onsider th e IRW ST vap or saturation p ressure ( b ased on IRW ST l iq uid tem p erature) to ex c eed th e c ontainm ent p ressure f or any p ostul ated DB A.

Figure 3.6-3 ( Figure 6.2.1-4 of Ref erenc e [ 3-1] ) sh ow s th e c ontainm ent p ressure and IRW ST w ater tem p erature resp onse during a L OCA and M SL B ac c ident. T h e IRW ST tem p eratures are c al c ul ated c onservativel y b y m ix ing th e c ondensed l iq uid in th e c ontainm ent w ith th e IRW ST w ater. T h e l im iting c ase is th e doub l e-ended disc h arge l eg sl ot b reak w ith m inim um SI f l ow f rom Ref erenc e [ 3-7] . T h e IRW ST m ax im um w ater tem p erature is 119.15 ° C

( 246.47 ° F) at 16,007 sec onds. Containm ent p ressure at th e m ax im um IRW ST w ater 2

tem p erature is 1.07 k g/ c m ( 15.21 p sia) h igh er th an saturation p ressure, w h ic h p rovides reasonab l e assuranc e th at w ater tem p erature does not ex c eed th e saturation tem p erature in th e range of c ontainm ent p ressures anal y z ed. T h eref ore, th e assum p tion th at c ontainm ent p ressure and IRW ST vap or p ressure are eq ual w h en eval uating NPSHa is ap p rop riate and c onservative f or th e ECCS and CSS.

(c ) W ater l evel T h e c ontrib ution of th e vol um e of w ater sp il l age f rom th e RCS is c onservativel y negl ec ted, and th e vol um e of w ater sp il l age f rom SIT s is avail ab l e in th ree of f our SIT s in ac c ordanc e w ith EPRI, Ch ap ter 5, Engineered Saf ety Sy stem , in V ol . II, AL W R Evol utionary Pl ant, of Advanc ed L igh t W ater Reac tor U til ity Req uirem ents Doc um ent ( Ref erenc e [ 3-8] ) .

W ith th e CSS ac tuated, th e reac tor c avity and in-c ore instrum entation ( ICI) c avity are assum ed to b e f l ooded to a l evel th at c an overf l ow onto th e f l oor at El . 100 f t th rough th e op enings of HL and CL p ip es at El . 114.29 f t. T h e HV T is al so j ust b el ow th e l evel at w h ic h w ater b egins to return to th e IRW ST th rough th e sp il l w ay s.

Sp ray w ater is h el d up on surf ac es th rough out th e c ontainm ent. T h e ac c um ul ation of w ater inside th e c ontainm ent inc l udes w ater h el d up on h oriz ontal surf ac es, c l ogged f l oor drains, w ater h el d up in c ontainm ent sp ray p ip es, w ater in th e c ontainm ent atm osp h ere, w ater f il m on vertic al surf ac es, p uddl es trap p ed on eq uip m ent, w ater soak ed into insul ation, and th e c ontainm ent f ree vol um e f il l ed w ith steam .

B ased on th e ab ove assum p tion, th e IRW ST w ater l evel f or th e NPSHa c al c ul ation is determ ined to b e 1.52 m ( 5 f t) ab ove th e IRW ST b ottom ( El . 81 f t) . T h e detail s of th e m inim um w ater l evel f or ESF op eration are desc rib ed in Sub sec tion 3.9.2.

( d) Head l oss Head l oss c al c ul ations f or th e NPSHa are b ased on h y draul ic m odel s of th e sy stem al igned to tak e suc tion f rom th e IRW ST . T h e sy stem c onf igurations of SIP suc tion and CSP/ SCP suc tion do not c h ange during an ac c ident. T h eref ore, th ese sy stem c onf igurations resul t in th e h igh est sum p f l ow rate, w h ic h is used f or siz ing th e IRW ST sum p strainers. T h e f l ow rate f or th e NPSHa c al c ul ation is c onservativel y b ased on th e m ax im um p um p f l ow rate.

T h ese c al c ul ations use Eq uations 2-1, 2-3, and 2-4 of Crane T ec h nic al Pap er No. 410, Fl ow KEPCO & KHNP 21

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 of Fl uid th rough V al ves, Fitting, and Pip e ( Ref erenc e [ 3-9] ) to determ ine th e h ead l oss due to f ric tional resistanc e in th e p ip ing and l ine l osses due to oth er c om p onent. T h e w ater tem p erature used f or h ead l oss c al c ul ation ( e.g., p ip e, f itting) is 10 ° C ( 50 ° F) of th e IRW ST m inim um tem p erature.

( e) Strainer h ead l oss T h e strainer h ead l oss uses a c onservative of 60.96 c m -w ater ( 2 f t-w ater) over th e tem p erature of interest. T h e ac tual deb ris h ead l oss is eval uated b y q ual if ied test resul ts c onduc ted sp ec if ic to th e APR1400 p l ant c onditions. T h e detail ed test p l an is p rovided in Ref erenc e [ 3-5] and th e test resul t is p rovided in Ap p endix C of th is rep ort. B ased on th e 2 2 resul ts of strainer testing, th e m ax im um h ead l oss f or th e 46.45 m ( 500 f t ) ef f ec tive strainer area w ith th e m ax im um deb ris l oad is 24.69 c m -w ater ( 0.81 f t-w ater) at th e design f l ow rate and inc l udes a c l ean sc reen c om p onent of 15.85 c m -w ater ( 0.52 f t-w ater) . As a resul t of th e strainer testing, a h ead l oss of ap p rox im atel y 41% of th e strainer design h ead l oss ensures adeq uate NPSH m argin f or th e ECCS p um p s.

T h e strainer h ead l oss of 60.96 c m -w ater ( 2 f t-w ater) rep resents a c onservative b ounding val ue and does not req uire tem p erature adj ustm ent. It is c onservative to use th ese val ues at h igh er tem p eratures sinc e f l uid density and visc osity dec rease w ith inc reasing tem p erature.

(f) Req uired NPSH General l y , th e NPSHr ( 3% ) is identif ied b y th e p um p vendor th rough testing as th e NPSHr to p revent a 3% l oss in p um p h ead ( NPSHr3% ) at rated f l ow . NPSHr is a p rop erty of th e p um p itsel f . Fol l ow ing th e guidanc e in SECY 0014, U se of Containm ent Ac c ident Pressure in Anal y z ing Em ergenc y Core Cool ing Sy stem and Containm ent Heat Rem oval Sy stem Pum p Perf orm anc e in Postul ated Ac c idents ( Ref erenc e [ 3-10] ) , th e f ol l ow ing unc ertainty f ac tors assoc iated w ith NPSHr are c onsidered to determ ine th e ef f ec tive NPSHr ( NPSHref f ) as f ol l ow s:

NPSHref f = ( 1 + unc ertainty ) NPSHr3%

T h e f ol l ow ing unc ertainty f ac tors th at af f ec t NPSHr devel op ed during p um p testing are c onsidered:

( 1) T h e NPSHr varies w ith c h anges in p um p sp eed c aused b y m otor sl ip .

( 2) T h e NPSHr dec reases w ith inc reasing w ater tem p erature.

( 3) Inc orrec tl y designed f iel d suc tion p ip ing adversel y af f ec ts th e NPSHr.

( 4) T h e air c ontent of th e w ater used in th e vendor' s test m ay b e l ow er th an th at of th e p um p ed w ater in th e f iel d.

( 5) W ear ring l eak age im p ac ts NPSHr.

T h e NPSHr c urves h ave not b een adj usted to c onsider th e p ositive im p ac t of inc reasing w ater tem p erature ( f ac tor ( 2) ) . T h is resul ts in a c onservative val ue f or NPSHr. A 21% total unc ertainty h as b een ap p l ied to ac c ount f or th e ef f ec ts of th e oth er f our unc ertainty f ac tors.

T h is unc ertainty is c onsistent w ith th at used in op erating p l ants. T h e ef f ec tive NPSHr of th e p roc ured p um p w il l b e c onf irm ed th rough Am eric an Soc iety of M ec h anic al Engineers ( ASM E)

Q M E-1 q ual if ic ation.

T h eref ore:

NPSHref f = ( 1 + 0.21) NPSHr3%

NPSHm = NPSHa - NPSHref f KEPCO & KHNP 22

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 In th e APR1400 design, th e design b asis NPSH req uired ( ef f ec tive NPSH req uired) f or th e CSPs and SIPs is sp ec if ied to inc l ude th e m argin ab ove th e nom inal NPSHr ( NPSH req uired 3% ) identif ied b y th e vendor. T h e design b asis NPSHr f or th e CSP is sp ec if ied as 5.33 m

( 17.5 f t) , al th ough th e nom inal val ue p rovided b y th e p um p vendor is 4.39 m ( 14.4 f t) . In addition, th e design b asis NPSH req uired f or th e SIP is sp ec if ied as 6.71 m ( 22.0 f t) , al th ough th e nom inal val ue p rovided b y th e p um p vendor is 5.56 m ( 18.23 f t) .

T h e NPSHr f or th e CSPs and SIPs at th e design f l ow rates is sh ow n in T ab l e 3.6-1.

2) Cal c ul ation resul ts An eval uation of th e SIP and CSP dem onstrates th at NPSHa is suf f ic ient during p ostul ated DB As.

T h e NPSHa is a f unc tion of th e suc tion p ip ing sy stem and is c al c ul ated using th e f ol l ow ing general eq uation:

NPSHa = h atm + h static -h l oss -h vp W h ere:

h atm = Head on th e l iq uid surf ac e resul ting f rom th e p ressure in th e atm osp h ere ab ove th e IRW ST , ( f t-w ater) h static = Head resul ting f rom th e dif f erenc e in el evation b etw een th e l iq uid surf ac e and c enterl ine of p um p suc tion, ( f t-w ater) h l oss = Head l oss resul ting f rom f l uid f ric tion and f ittings in th e f l ow p ath to th e p um p suc tion f l ange, ( f t-w ater) h vp = Head eq uival ent to th e vap or p ressure of th e w ater at th e w ater tem p erature, ( f t-w ater)

For th is anal y sis, h atm and h vap are c onsidered as th e f ol l ow ing b ased on th e m ax im um of th e initial c ontainm ent p ressure and th e saturation p ressure at th e tem p erature ( T ) of th e p um p ed f l uid.

( a) For T > 100 ° C ( 212 ° F) h atm = h vp (b ) For T < 100 ° C ( 212 ° F) h atm = Head eq uival ent to m ax im um of th e initial c ontainm ent p ressure b ef ore p ostul ated L OCA h vp = Head eq uival ent to vap or p ressure at T T h e h ead eq uival ent to th e vap or p ressure of th e w ater at th e w ater tem p erature varies w ith tem p erature. For IRW ST w ater p rop erties during th e p eriod b ef ore th e IRW ST reac h es 100 ° C

( 212 ° F) , th e anal y sis assum es sub c ool ed l iq uid at 1 atm ( 14.7 p sia) , w h ic h is th e c ontainm ent p ressure b ef ore th e ac c ident. W h en th e IRW ST tem p erature is greater th an 100 ° C ( 212 ° F) , th e c ontainm ent p ressure is eq ual to th e IRW ST l iq uid vap or p ressure.

T h e p eak IRW ST tem p erature f rom Figure 3.6-3 is 119.15 ° C ( 246.47 ° F) . T h e l im iting eval uation of th e NPSH c redits c ontainm ent ac c ident p ressure sinc e it c onservativel y assum es th e IRW ST l iq uid is at th e saturation p ressure c orresp onding to th e p eak c al c ul ated IRW ST tem p erature.

T h e NPSHm is c al c ul ated f or th e SIPs and CSPs f or c ool ant tem p eratures f rom 48.9 ° C ( 120 ° F) to 121.1 ° C ( 250 ° F) b ased on th e c ontainm ent p ressure and tem p erature f or th e p ost-ac c ident l ong-term p h ase, as sh ow n in Figure 3.6-3. T h e NPSHm f or th e SIPs f or th e range of p ost-L OCA c ool ant tem p eratures is inc l uded as T ab l e 3.6-2, and th e NPSHm f or th e CSPs is inc l uded as T ab l e KEPCO & KHNP 23

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.6-3.

T h e tim e-dep endent NPSH c urves sh ow n in Figures 3.6-4 and 3.6-5 are b ased on Figure 3.6-3.

T h ese f igures rep resent th e m ost l im iting p um p s ( CSP PP01B and SIP PP02D) and dem onstrate p ositive NPSH m argin f or al l ESF p um p s over a f ul l range of IRW ST tem p eratures.

As il l ustrated in Figures 3.6-4 and 3.6-5, th e NPSHa ex c eeds th e NPSHr f or al l ex p ec ted sum p tem p eratures ( and th eref ore, at al l tim es th rough out th e L OCA transient) . T h e m inim um NPSHm c al c ul ated w ith th is m eth odol ogy is ap p rox im atel y 0.53 m ( 1.73 f t) f or th e SIP and 0.91 m ( 3.0 f t) f or th e CSP. T h eref ore, th e IRW ST sum p strainer of th e APR1400 p rovides suf f ic ient NPSHa to ensure rel iab l e op eration of th e ECCS p um p s and CSPs.

3.6.3 Cavitation Erosion Sub sec tion 6.3 of Enc l osure 1 of SECY 0014 ( Ref erenc e [ 3-10] ) desc rib es th e erosion ef f ec ts of p um p op eration due to insuf f ic ient NPSH m argin. Pum p tests indic ate th at th e z one of m ax im um erosion rate l ies b etw een NPSHm ratios ( NPSHa/ NPSHr) of 1.2 to 1.6, and guidanc e is p rovided to l im it th e tim e of op eration in th is z one to 100 h ours. For th e SIPs w ith an NPSHr of 6.71 m ( 22.0 f t) , th e range of NPSHa val ues th at c orresp ond to th e m ax im um erosion z one is 8.05 to 10.73 m ( 26.4 to 35.2 f t) . From T ab l e 3.6-2, th ese p um p s ex p erienc e m ax im um erosion w h en th e f l uid tem p erature is b etw een ab out 87.8 ° C

( 190 ° F) and 98.9 ° C ( 210 ° F) . Sim il arl y , th e m ax im um erosion NPSHa range f or th e CSPs w ith an NPSHr of 5.33 m ( 17.5 f t) is 6.40 to 8.53 m ( 21.0 to 28.0 f t) . From T ab l e 3.6-3, th ese NPSHa val ues oc c ur w h en th e f l uid tem p erature is b etw een ap p rox im atel y 93.3 ° C ( 200 ° F) and 100 ° C ( 212 ° F) . A review of th e tem p erature data in Figure 3.6-3 indic ates th at th e total duration, w h en th e IRW ST f l uid tem p erature is b etw een 90.6 ° C ( 190 ° F) and 100 ° C ( 212 ° F) , is ap p rox im atel y 90,000 sec onds ( ap p rox im atel y 25 h ours) ,

w h ic h is w ith in th e 100 h our l im it rec om m ended in Sub sec tion 6.3.3 of SECY 0014 ( Ref erenc e [ 3-10] ) .

KEPCO & KHNP 24

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.7 Strainer V ortex ing, Air Inj ection, Flashing, and Deaeration Assessment IRW ST sum p strainer sub m ergenc e is adeq uate to p rec l ude vortex ing, sum p f l uid f l ash ing, and deaeration induc ed b y ex c essive dif f erential p ressure drop . V ortex ing c oul d c ause th e ingestion of unac c ep tab l e q uantities of air into th e ECCS p um p s and CSPs, p otential l y resul ting in unac c ep tab l e p um p p erf orm anc e.

W h en f l ash ing to steam , w ater c an resul t in rec irc ul ating c ool ant th at transf orm s a p ortion of th e f l uid into th e vap or p h ase if th e strainer p ressure drop is suf f ic ientl y l arge.

3.7.1 Strainer V ortex ing During th e p rototy p e testing, visual ob servations are req uired to ensure th at no signif ic ant vortic es h ave f orm ed. V ortex and/ or sw irl up to and inc l uding a T y p e 4 are c onsidered ac c ep tab l e. T h e testing is p erf orm ed at th e sub m ergenc e req uirem ent of 60.96 c m ( 2 f t) sub m ergenc e, and no vortic es are ob served.

Additional l y , th ere is no p ossib il ity of th e oc c urrenc e of vortex ing or air ingestion geom etric al l y b ec ause th e IRW ST sum p strainers are m ounted at th e top of th e p it and suc tion is tak en at th e b ottom of th e p it.

3.7.2 Flashing in the Deb ris Bed T h e strainer f l ash ing req uirem ent is c onservativel y m et if th e p ressure drop ac ross th e deb ris b ed is l ess th an th e sub m ergenc e. B ased on th e IRW ST m inim um w ater l evel of El . 86 f t ( i.e., 1.52 m ( 5 f t) ab ove th e APR1400 IRW ST b ottom f l oor of El . 81 f t) f or ECCS p um p NPSH and th e strainer assem b l y h eigh t of 84 f t ( 81 f t p l us 3 f t) , th is p rovides 60.96 c m ( 2 f t) sub m ergenc e under L OCA c onditions. T h e m ax im um strainer h ead l oss is 32.31 c m -w ater ( 1.06 f t-w ater) at 60 ° C ( 140 ° F) . T h e strainer sub m ergenc e l evel ex c eeds th e assoc iated h ead l oss. If th e surf ac e p ressure is c onservativel y assum ed at th e saturation p ressure of th e IRW ST w ater tem p erature, th e l oc al static p ressure af ter th e strainer is not l ess th an th e saturation p ressure, and f l ash ing does not oc c ur ac ross th e strainer surf ac e.

During testing, th e m ax im um ob served h ead l oss ac ross th e strainer is l ess th an 24.69 c m ( 0.81 f t) , w h ic h p rovides additional m argin to f l ash ing.

3.7.3 Deaeration of Sump Fluid at Strainer T h e IRW ST sum p strainer sub m ergenc e during p ost-L OCA is greater th an th e ob served h ead l oss under l oss of c ool ant c onditions. Sinc e sol ub il ity of gas in w ater is direc tl y p rop ortional to th e f l uid p ressure, th e inc rease in sol ub il ity of air due to th e static p ressure inc rease of th e w ater ab ove th e strainer is m ore th an enough to c om p ensate f or th e dec rease in sol ub il ity of air due to th e h ead l oss ac ross th e strainer.

T h eref ore, deaeration of f l uid does not oc c ur. T h e design h ead l oss val ue is a c onservative val ue aim ed p rim aril y at m inim iz ing th e c al c ul ated NPSH f or th e ECCS p um p s, and does not im p l y deaeration even th ough it m ay b e greater th an th e strainer sub m ergenc e.

KEPCO & KHNP 25

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.8 Chemical Ef f ects A c h em ic al ef f ec ts eval uation is p erf orm ed f ol l ow ing th e c h em ic al ef f ec ts eval uation p roc ess sh ow n in Figure 1 of Enc l osure 3 of Ref erenc e [ 2-3] . No ex c ep tion is tak en w ith regards to th e guidanc e p rovided.

In order to assess p otential c h em ic al ef f ec ts in th e APR1400 sum p , th e m aterial s th at are in th e c ontainm ent b uil ding th at m ay reac t w ith c ool ant in th e p ost-ac c ident c ontainm ent environm ent h ave b een identif ied. Reac tive p l ant m aterial s in th e c ontainm ent b uil ding are c ategoriz ed as m etal l ic and non-m etal l ic item s and general l y inc l ude insul ation and c onc rete, as w el l as oth er p otential sourc es of al um inum . T h e m aterial s inventory inc l udes th e overal l m ass, l oc ation in c ontainm ent and p otential f or b eing sp ray ed w ith or im m ersed in c ool ant f ol l ow ing a L OCA.

T h e W CAP-16530-NP m eth odol ogy ( Ref erenc e [ 3-11] ) ref erenc ed in NRC RG 1.82 ( Ref erenc e [ 1-1] )

p rovides a c onservative m odel to p redic t th e c orrosion and dissol ution of c ontainm ent m aterial s in a p ost-L OCA environm ent and th e f orm ation of c h em ic al p rec ip itates f or p artic ip ating PW Rs. T h e p rim ary c orrosion p roduc ts c ontrib uting to th ese c h em ic al p rec ip itates are c al c ium , sil ic on, al um inum , and th e p rec ip itates th at c an f orm al um inum ox y -h y drox ide, c al c ium p h osp h ate, and sodium al um inum sil ic ate.

Surrogate susp ensions of c h em ic al p rec ip itates rep resenting th is c h em ic al deb ris c an b e inc l uded as an additional deb ris sourc e to th e strainer testing p rogram to q ual if y th e strainer f or c h em ic al ef f ec ts. T h e q uantities of c h em ic al p rec ip itates are b ased on reac tive m aterial surf ac e areas and q uantities, tem p erature, w ater l evel , p H, and oth er p aram eters rel ated to th e p l ant sp ec if ic environm ent and p ost-ac c ident evol ution.

3.8.1 Containment Spray pH Control T h e p H of IRW ST w ater is eval uated to p rovide reasonab l e assuranc e th at th e c al c ul ated m inim um and m ax im um p H val ues under any p ossib l e w ater c h em istry c onditions c aused b y a L OCA are b etw een 7.0 and 8.5. T h e IRW ST and c ontainm ent sp ray p H ranges are 4 to 10 f or sh ort term DB A c ondition, b ased on APR1400 op erating c onditions and p ast op erating ex p erienc e, and 7 to 8.5, using th e tri-sodium p h osp h ate as b uf f ering agent, f or l ong term DB A c ondition. T h ese val ues are b ased on th e m ax im um and m inim um p H c al c ul ations. T h e IRW ST p H ranges are inc l uded in T ab l e 3.8-1.

3.8.2 Assumptions

1) T h e m ax im um IRW ST w ater vol um e is used f or th e c h em ic al ef f ec ts anal y sis in term s of th e c onc entration or sol ub il ity of th e el em ents even th ough th e sensitivities f or th e m inim um and m ax im um IRW ST w ater vol um es h ave no im p ac t on th e f inal p rec ip itates resul ts due to th e l im ited am ount of f ib ergl ass deb ris.

2) T h e m ax im um IRW ST and sp ray p H val ues of 10 f or sh ort-term DB A and 8.5 f or l ong-term DB A f rom T ab l e 3.8-1 are c onservativel y used b ec ause total dissol ution and p rec ip itate generation inc rease as p H inc reases, as sh ow n in Figure 6.5-5 of Ref erenc e [ 3-11] . Figure 3.8-1 sh ow s th e IRW ST and c ontainm ent sp ray p H versus tim e c urve used in th e c h em ic al ef f ec ts anal y sis.

3) T h e l im iting L OCA sc enario th at y iel ds th e h igh est sum p tem p erature is used to m ax im iz e th e am ount of c h em ic al p rec ip itates. T h e c ontainm ent and sum p tem p erature p rof il es ex tended to 30 day s are c al c ul ated using th e GOT HIC c om p uter c ode. T h e detail ed m odel desc rip tion to c al c ul ate th e h igh est sum p tem p erature is p rovided in Ap p endix B of Ref erenc e [ 3-7] .

4) T h e CSS is op erated f rom th e ac c ident initiation and c ontinued f or 30 day s to m ax im iz e th e ex p osure of c ontainm ent sp ray to unsub m erged m aterial s.

KEPCO & KHNP 26

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.8.3 Evaluation Summary Al um inum and c onc rete, th e identif ied c ontainm ent m aterial s to b e c onsidered f or c h em ic al ef f ec t in th e APR1400, are signif ic ant c ontrib utors to p roduc tion of th e c orrosion p roduc ts b ased on W CAP-16530-NP

( Ref erenc e [ 3-11] ) .

T h e c onc rete in th e reac tor c ontainm ent is th e onl y c onc rete w ith q ual if ied c oating. Q ual if ied c oatings are assum ed to f ail as a direc t resul t of th e HEL B Z OI. T h e f ail ure resul ts in th e c oated c onc rete b ec om ing ex p osed to th e sum p / sp ray f l uid. An ap p l ied Z OI f or q ual if ied c oatings is 10 tim es th e ID of th e rup tured p ip e f or a c onservative estim ate. U nder m ost c irc um stanc es, a 10D Z OI ex p ands b ey ond th e w al l s and f l oor of th e b reak c om p artm ent. In th is c ase, it is c onservative to estim ate th e surf ac e area of th e c onc rete as th e sum of th e areas of th e w al l s and f l oor of th e c om p artm ent ( inc l uding any oth er c onc rete surf ac es inside th e c om p artm ent) . T h is val ue is l arger th an th e q uantity of q ual if ied c oatings ( 4D Z OI) destroy ed b y th e HEL B .

T h e surf ac e area of c onc rete struc tures w ith q ual if ied c oating is estim ated f rom th e c ivil struc tural draw ings and th ree-dim ensional c om p uter-aided design ( CAD) p rogram . T h e surf ac e area c onsists of w al l s, f l oors, and eq uip m ent p edestal s. Onl y th e surf ac e area th at is c ontac t w ith th e sum p p ool and c ontainm ent sp ray is p rovided. T h e estim ated surf ac e areas are divided into tw o c ategories: sub m erged

( p ool ) and unsub m erged ( sp ray ) surf ac e areas.

T h e sourc es of al um inum in c ontainm ent of th e APR1400 are assoc iated w ith th e f ol l ow ing ty p es of eq uip m ent:

1) Heating, ventil ation, and air c onditioning ( HV AC) eq uip m ent ( f our reac tor c ontainm ent f an c ool ers, f our SG enc l osure rec irc ul ation f ans, f our annul us area rec irc ul ation f ans, and duc t insul ation)

2) Ex -c ore detec tors

3) Ref uel ing eq uip m ent

4) Control el em ent drive m ec h anism ( CEDM ) c ool ing f an

5) Surveil l anc e c ap sul e h andl ing tool s ( retrieval tool and rem ote p ositioning tool )

6) POSRV SIEKA-Ac tuators T h e al um inum surf ac e area is b rok en dow n into sub m erged and unsub m erged ( sp ray ) z ones.

T h e am ount of c onc rete and al um inum in th e c ontainm ent is p rovided in T ab l e 3.8-2.

T h e inp ut data f or W CAP-16530-NP c h em ic al p roduc t f orm ation, th e p rec ip itates p roduc ed, and th e anal y sis resul ts are inc l uded in T ab l es 3.8-3, 3.8-4, and 3.8-5, resp ec tivel y .

KEPCO & KHNP 27

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 3.9 U pstream Ef f ect 3.9.1 H oldup V olumes T h e eval uation of th e up stream ef f ec t is a review of th e f l ow p ath s l eading to th e IRW ST , identif y ing th e f l ow p ath s th at c oul d resul t in b l oc k ing th e return w ater th at c h al l enges th e IRW ST m inim um w ater l evel eval uation f or ESF op eration. T h e eval uation al so inc l udes identif y ing th e h ol dup vol um es, suc h as rec essed areas and enc l osed room s, f or w h ic h trap p ed w ater does not return to th e IRW ST . Al l of th e h ol dup vol um es are tak en ac c ount of in th e m inim um w ater l evel c al c ul ation.

Figures 3.9-1 and 3.9-2 sh ow a sc h em atic of CS and b l ow dow n return p ath w ay s, and th e sc h em atic of p otential w ater trap s in c ontainm ent. During l ong-term c ool ing sub seq uent to an RCS p ip e b reak ,

b orated w ater is draw n f rom th e IRW ST b y th e SIPs and inj ec ted into th e RV f or c ore c ool ing.

T h e w ater is ej ec ted to th e b ottom f l oor of th e c ontainm ent w ith in th e sec ondary sh iel d w al l th rough th e h oriz ontal p l atf orm s w h ic h are c onstruc ted of op en grating w ith in th e SG c om p artm ents.

T h e CSPs al so draw w ater f rom th e IRW ST sum p s to c ool th e c ontainm ent b uil ding. T h is w ater rains dow n on al l c ontainm ent surf ac es, and th en drains to th e b ottom f l oor of c ontainm ent w ith in th e sec ondary sh iel d w al l and annul us via th e stairw ay and a ring of dec k grating around m uc h of th e c irc um f erenc e of th e b uil ding.

T h ere are tw o 10 inc h drain p ip es in th e ref uel ing c avity th at are c onnec ted to th e b ottom p ortion of th e c ontainm ent. T h e ref uel ing c avity surrounds th e up p er p art of th e reac tor and ex tends f rom th e op erating f l oor at El . 156 f t dow n to th e reac tor h ead f l ange at El . 130 f t. T h e w est p art of th e c avity enc om p asses th e up p er guide struc ture ( U GS) l ay dow n area w h ic h ex tends dow n to El . 106 f t 6-3/ 8 in. T h e east p art of th e ref uel ing c avity enc om p asses th e f uel transf er sy stem up ender and c ore sup p ort b arrel ( CSB ) l ay dow n area. T h e f uel transf er sy stem up ender and th e CSB l ay dow n area ex tends dow n to El . 114 f t 6 in.

T h e c avity c an c ol l ec t ap p rox im atel y 9% of th e c ontainm ent m ain sp ray f l ow and f il l up ex c ep t f or th e tw o f l oor drains. B oth drains are 10 inc h diam eter drain p ip es in th e f l oor of th e ref uel ing c avity l iner. One c om b ined drain is th e CSB l ay dow n area and th e f uel transf er sy stem up ender area, and th e oth er is th e U GS l ay dow n area. B oth drain to El . 100 f t area.

A c onc ern w ith th e ref uel ing c avity is th e p otential f or p iec es of deb ris ( e.g., a 25. 4 c m x 25.4 c m ( 10 inc h x 10 inc h ) p iec e of RM I) to m igrate to one or b oth drains and greatl y restric t th e f l ow so th at th e ref uel ing c avity m ay f il l . T h e w ater sp ray ed on th e ref uel ing c avity area is f inal l y gath ered to th e l ow est p arts of th e ref uel ing c avity , U GS l ay dow n area, and CSB l ay dow n area, w h ic h h y p oth etic al l y c oul d h ol d th ousands of c ub ic f eet of w ater if th eir drains are b l oc k ed. How ever, th is sc enario is deem ed not c redib l e. No h igh -

energy p ip es are near th e 10 inc h op enings th at drain th e ref uel ing c avity . T h e 10 inc h drains are op en w ith no c overs, grates, or sc reens, so th e m inim um f l ow restric tion in th e c avity drain l ine f l ow p ath is th e inner diam eter of th e 10 inc h drain l ine. Deb ris needs to b e at l east 10 inc h es w ide to b ridge th e op ening and c ause b l oc k age. Sm al l er deb ris p asses straigh t th rough . Deb ris al so needs to b e p l anar in order to adeq uatel y seal th e op ening. A c rum p l ed p iec e of RM I w oul d not seal th e op ening.

W ater sp il l ed f rom RCS b reak and th e unif orm l y distrib uted CS w ater drains b ac k to th e HV T , and th en drains to th e IRW ST via sp il l w ay s. Sinc e th ere are f our p ath w ay s on th e b ottom f l oor of th e c ontainm ent

( tw o 0.91 m ( 3 f t) w ide p ath w ay s are p ersonnel entranc es l eading into sec ondary sh iel d w al l f rom annul us and tw o 2.92 m ( 9 f t 7 inc h ) w ide p ath w ay s are l oc ated at th e f ront of th e HV T trash rac k s in th e sec ondary sh iel d w al l ) , th e deb ris w oul d not c l og th ese p ath w ay s. As a resul t, no c h ok e p oints th at c oul d b l oc k th e KEPCO & KHNP 28

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 f l ow p ath s of return w ater are identif ied. T h eref ore, onl y th e h ol dup vol um es m ay c h al l enge th e m inim um w ater l evel of th e IRW ST f or ESF op eration.

T h e following assum p tions are m ade in th e c al c ul ation f or h ol dup vol um e c onservatism :

1) T h e L B L OCA is assum ed so th at th e c ool ant c om p l etel y f il l s th e reac tor c avity and ICI c avity .

2) T h e w ater transf er f rom th e HV T into th e IRW ST is assum ed to sp il l over into th e IRW ST th rough one sp il l w ay to m ax im iz e w ater vol um e to b e h el d up in th e HV T .

3) A p ortion of th e CS is del ay ed in th e c ontainm ent b uil ding. T h e m ax im um CS f l ow rate f or a tw o-train op eration is assum ed to c onservativel y m ax im iz e th e CS h ol d up .

4) T h e am ount of w ater needed to f il l th e SIS and CSS is th e vol um e of SIS and CSS p ip ing ab ove th e m inim um w ater l evel during norm al op eration.

5) T h e m ax im um c ontainm ent atm osp h eric c onditions at CSAS are assum ed f or eac h sc enario to m ax im iz e w ater th at w oul d b e h el d up in th e atm osp h ere. CS w ater m ay b e h el d up in th e c ontainm ent atm osp h ere, in th e c ontainm ent sp ray drop l ets, and in th e c ondensation on c ontainm ent b uil ding and eq uip m ent surf ac es. A f rac tion of th e total w ater del ivered to c ontainm ent evap orates in th e c ontainm ent atm osp h ere. T h e evap oration q uantity is c al c ul ated b ased on th e steam m ass and p ressure c onditions at CSAS as determ ined in th e assoc iated anal y ses. CS vol um e h ol dup is determ ined b y c al c ul ating th e f al l tim e at term inal vel oc ity f or w ater drop l ets f rom th e m ain sp ray m edian h eader h eigh t and th e average drop diam eter, and th e f al l tim e at term inal vel oc ity f or drop l ets f rom th e aux il iary sp ray m edian h eader h eigh t and average drop diam eter. T h e del ay ed vol um e is th us th e p roduc t of th e f al l tim e and th e m ax im um sp ray f l ow rate f or eac h sy stem .

6) Condensation h ol dup on h oriz ontal and vertic al surf ac es f or c ontainm ent w al l s, struc tures, and eq uip m ent is determ ined b y c al c ul ating a total surf ac e area and th en ap p l y ing a unif orm w ater f il m th ic k ness. T h is val ue is c onsidered c onservative b ec ause no distinc tion is m ade f or surf ac e area orientation; th e w ater f il m is assum ed to b e unif orm over al l h oriz ontal and vertic al surf ac es.

7) T h e m inim um IRW ST and SIT vol um es are assum ed to m inim iz e w ater transf erred to th e c ontainm ent f l oor during inj ec tion.

T h e holdup vol um es are c ategoriz ed into tw o group s: Hol dup vol um e on th e w ay s to th e IRW ST and inac tive p ool vol um e. T w o group s are def ined as f ol l ow s:

1) Hol dup vol um e on th e w ay s to th e IRW ST In a LOCA, th e IRW ST w ater returns f rom th e CS noz z l e and b rok en p ip e. T h e h el d-up w ater on th e w ay to th e IRW ST dec reases th e initial IRW ST w ater l evel . T h e f ol l ow ing are th e sourc e of h el d-up w ater on th e w ay to th e IRW ST .

( a) CS susp ended w ater in th e c ontainm ent atm osp h ere (b ) CS steam w ater (c ) Initial f il l ing w ater f or th e SIS and CSS p ip e

( d) Condensate w ater on various surf ac es

( e) W ater stream on th e f l oor at El . 100 f t KEPCO & KHNP 29

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 (f) W ater steam on th e ref uel ing p ool f l oor

2) Inac tive p ool s vol um e An inac tive p ool vol um e is def ined as a h ol dup vol um e th at entrap s return th at w il l not c ontrib ute to rec overing th e IRW ST w ater l evel . T h e f ol l ow ing are c onsidered as th e inef f ec tive p ool s:

( a) HV T w ater vol um e to f il l up to l evel th at c an f l ow b ac k into th e IRW ST th rough th e sp il l w ay s (b ) Reac tor c avity and ICI c avity vol um e (c ) Containm ent drain sum p vol um e

( d) ICI c avity sum p vol um e T h e c al c ul ated h ol dup vol um es are p rovided in T ab l e 3.9-1.

3.9.2 M inimum Water Level f or ESF operation T h e f ol l ow ing assum p tions are m ade f or w ater sourc es to m inim um w ater l evel determ ination:

1) W ater sourc es avail ab l e to p rovide f l ood w ater vol um e are th e IRW ST vol um e.

2) RCS sp il l age f rom a b reak p oint is not c redited.

3) T h ree SIT s vol um es are added to th e IRW ST inventory to estab l ish th e total vol um e of w ater avail ab l e f or f l ooding.

4) T h e m inim um IRW ST and SIT vol um es are assum ed to m inim iz e w ater transf erred to th e c ontainm ent f l oor during inj ec tion.

T h e m inim um w ater l evel of IRW ST f or ESF op eration p rovides th e b asis f or estim ating static h ead in th e NPSH eval uation, as desc rib ed in Sec tion 3.6. It is c onservativel y c al c ul ated as f ol l ow s:

3 During norm al op eration, th e IRW ST is not l ess th an 2,373.5 m ( 627,000 gal l ons, 74.43% w ater l evel s of th e IRW ST ) to ensure an adeq uate sup p l y of b orated w ater to th e SIS and CSS. T h e IRW ST is designed to m inim iz e w ater evap oration, h ow ever, if th e w ater reac h es a l evel of l ess th an 74.43% . T h e m ak eup op eration f rom th e b oric ac id storage tank via th e b oric ac id m ak eup p um p is ac tivated and c ontinued until 74.43% w ater l evel is rec overed. T h is l evel is def ined as b el ow norm al w ater l evel of th e IRW ST and is used as th e initial w ater l evel f or p ostul ated ac c idents. In c ase of an L B L OCA, th e w ater m ass in th e SIT c an c ontrib ute to rec overing th e IRW ST , and w ater in th ree of th e f our SIT s is c onsidered in th e c al c ul ation in ac c ordanc e w ith Ref erenc e [ 3-8] .

T h e m inim um w ater l evel of th e IRW ST f or ESF op eration during a L OCA is c al c ul ated b y sub trac ting th e h ol dup vol um e f rom th e initial w ater vol um e in th e IRW ST and b y adding th e vol um e in th ree SIT s. T h e m inim um w ater l evel f or ESF op eration used in th e NPSH eval uation is c al c ul ated as 1.52 m ( 5 f t) ab ove th e IRW ST b ottom ( El . 81 f t) and is sh ow n in Figure 3.9-3.

KEPCO & KHNP 30

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.1-1 Postul ated B reak Pip e L ines Siz e L oc ation Inside Sec ondary Sh iel d W al l Pip e L ines Outside ID SG PZ R Sec ondary

( inc h ) Com p artm ent Sh iel d W al l Com p artm ent No. 1 No. 2 Hot l eg l ines 42 X X Col d l eg l ines 30 X X PZ R surge l ine 12 X SCP inl et l ines 12.812 X X DV I l ines 10.126 X X Ch arging l ine 2.624 X PZ R aux . sp ray l ine 2.624 X POSRV l ines 7.75 X SIT inj ec tion l ines 10.126 X X X M ain steam l ines 30.907 X X X KEPCO & KHNP 31

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.2-1 Deb ris Generation f or B reak L oc ations B reak L oc ation RCS Hot L eg L ine RCS Col d L eg L ine M ain Steam L ine Item NEI 04-07 NEI 04-07 NEI 04-07 Ap p l ic ab l e M eth odol ogy and SE and SE and SE B reak Siz e ( c m / inc h ) 106.7 / 42 76.2 / 30 78.5 / 30.907 Insul ation ( 2D) 2.13 / 7 1.52 / 5 1.58 / 5.2 Siz e of Z OI

( m / f t) Coating

- 4D ( ep ox y ) 4.27 / 14 3.05 / 10 3.17 / 10.4

- 10D ( IOZ ) 10.67 / 35 7.62 / 25 7.92 / 26 RM I TS 3 3 (m / ft) 3 3 Coating ( m / ft) 0.086 / 3.03 0.039 / 1.39 0.012 / 0.42 Am ount - 4D ( ep ox y ) 0.052 / 1.82 0.005 / 0.18 0.006 / 0.21

- 10D ( IOZ ) 0.034 / 1.21 0.034 / 1.21 0.006 / 0.21 L atent Deb ris 90.72 / 200 90.72 / 200 90.72 / 200

( k g/ lb m )

Note :

3

( 1) For strainer design, ep ox y c oating of 3.10 f t is c onservativel y used.

KEPCO & KHNP 32

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.3-1 Siz e and Distrib ution of Deb ris Deb ris Siz e Distrib ution Deb ris Sourc e T y p e Fines ( % ) L arge Piec es ( % )

RM I 75 25 Coating 100 0 Fib er 7.5 0 L atent Partic l e 92.5 0 KEPCO & KHNP 33

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.3-2 Deb ris Prop erties Deb ris Sourc e T y p e Prop erty V al ue 3 3 RM I Density 7.85 g/ c m ( 490 l b m / f t )

-4 Diam eter of p artic l e ( Dp ) 10 m 94x 10 inc h )

Coating Partic l e density ( µp )

( 1) 3 3

- ep ox y 1.51 g/ c m ( 94 l b m / f t )

3 3

- IOZ 7.32 g/ c m ( 457 l b m / f t )

3 3 L atent Partic ul ate Partic l e density ( µp ) 2.70 g/ c m ( 168.6 l b m / f t )

As-f ab ric ated ( th eoretic al 3 3 0.038 g/ c m ( 2.4 l b m / f t )

Pac k ing) density ( c o)

L atent Fib er ( NU KON) 3 3 Fib er density ( µf ) 1.50 g/ c m ( 93.6 l b m / f t )

Note:

( 1) Ref erenc ed f rom T ab l e 3-3 of NEI-04-07 KEPCO & KHNP 34

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.6-1 NPSHr f or SI Pum p and CS Pum p

( 1) ( 2)

Fl ow Rate NPSHr3% NPSHref f Pum p

( L / m in / gp m ) ( m -w ater/ f t-w ater) ( m -w ater/ f t-w ater)

SI p um p 4,675 / 1,235 5.56 / 18.23 6.71 / 22 CS p um p 20,536 / 5,425 4.39 / 14.4 5.33 / 17.5 Note :

( 1) NPSHr3% is p rovided b y th e p um p vendor as a resul t of f ac tory testing as th e val ue of NPSH w h ic h resul ts in a 3% drop in p um p disc h arge h ead. NPSHr3% is a p rop erty of th e p um p itsel f .

( 2) NPSHref f ( ef f ec tive req uired NPSH) is th e NPSHr3% val ue w ith unc ertainties in NPSHr inc l uded. Fol l ow ing th e guidanc e of SECY 0014 ( Ref erenc e [ 3-10] ) , unc ertainties assoc iated w ith NPSHr are c onsidered to determ ine th e ef f ec tive NPSHr ( NPSHref f ) .

KEPCO & KHNP 35

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.6-2 SI Pum p NPSH Eval uation Resul ts Sum p T em p . h atm h static h l oss Hvp NPSHa NPSHref f M argin

( ° F) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) 120 34.30 30 6.28 3.95 54.08 22.0 32.08 125 34.34 30 6.28 4.58 53.49 22.0 31.49 130 34.4 30 6.28 5.21 52.92 22.0 30.92 135 34.44 30 6.28 6.00 52.17 22.0 30.17 140 34.49 30 6.28 6.79 51.43 22.0 29.43 145 34.53 30 6.28 7.77 50.49 22.0 28.49 150 34.59 30 6.28 8.76 49.56 22.0 27.56 155 34.65 30 6.28 9.98 48.40 22.0 26.40 160 34.69 30 6.28 11.2 47.22 22.0 25.22 165 34.77 30 6.28 12.71 45.79 22.0 23.79 170 34.82 30 6.28 14.21 44.34 22.0 22.34 175 34.88 30 6.28 16.04 42.57 22.0 20.57 180 34.94 30 6.28 17.87 40.80 22.0 18.80 185 35.02 30 6.28 20.09 38.66 22.0 16.66 190 35.07 30 6.28 22.31 36.49 22.0 14.49 195 35.13 30 6.28 24.96 33.90 22.0 11.90 200 35.21 30 6.28 27.63 31.31 22.0 9.31 205 35.28 30 6.28 30.81 28.20 22.0 6.20 210 35.35 30 6.28 34 25.08 22.0 3.08 212 35.39 30 6.28 35.39 23.73 22.0 1.73 215 37.7 30 6.28 37.7 23.73 22.0 1.73 220 41.54 30 6.28 41.54 23.73 22.0 1.73 225 45.98 30 6.28 45.98 23.73 22.0 1.73 230 50.43 30 6.28 50.43 23.73 22.0 1.73 235 55.65 30 6.28 55.65 23.73 22.0 1.73 240 60.89 30 6.28 60.89 23.73 22.0 1.73 245 66.95 30 6.28 66.95 23.73 22.0 1.73 250 73.06 30 6.28 73.06 23.73 22.0 1.73 KEPCO & KHNP 36

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.6-3 CS Pum p NPSH Eval uation Resul ts Sum p T em p . h atm h static h l oss Hvp NPSHa NPSHref f M argin

( ° F) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) ( f t-w ater) 120 34.30 30.16 9.67 3.95 50.85 17.5 33.35 125 34.34 30.16 9.67 4.58 50.26 17.5 32.76 130 34.4 30.16 9.67 5.21 49.69 17.5 32.19 135 34.44 30.16 9.67 6.00 48.94 17.5 31.44 140 34.49 30.16 9.67 6.79 48.20 17.5 30.70 145 34.53 30.16 9.67 7.77 47.26 17.5 29.76 150 34.59 30.16 9.67 8.76 46.33 17.5 28.83 155 34.65 30.16 9.67 9.98 45.17 17.5 27.67 160 34.69 30.16 9.67 11.2 43.99 17.5 26.49 165 34.77 30.16 9.67 12.71 42.56 17.5 25.06 170 34.82 30.16 9.67 14.21 41.11 17.5 23.61 175 34.88 30.16 9.67 16.04 39.34 17.5 21.84 180 34.94 30.16 9.67 17.87 37.57 17.5 20.07 185 35.02 30.16 9.67 20.09 35.43 17.5 17.93 190 35.07 30.16 9.67 22.31 33.26 17.5 15.76 195 35.13 30.16 9.67 24.96 30.67 17.5 13.17 200 35.21 30.16 9.67 27.63 28.08 17.5 10.58 205 35.28 30.16 9.67 30.81 24.97 17.5 7.47 210 35.35 30.16 9.67 34 21.85 17.5 4.35 212 35.39 30.16 9.67 35.39 20.50 17.5 3.00 215 37.7 30.16 9.67 37.7 20.50 17.5 3.00 220 41.54 30.16 9.67 41.54 20.50 17.5 3.00 225 45.98 30.16 9.67 45.98 20.50 17.5 3.00 230 50.43 30.16 9.67 50.43 20.50 17.5 3.00 235 55.65 30.16 9.67 55.65 20.50 17.5 3.00 240 60.89 30.16 9.67 60.89 20.50 17.5 3.00 245 66.95 30.16 9.67 66.95 20.50 17.5 3.00 250 73.06 30.16 9.67 73.06 20.50 17.5 3.00 KEPCO & KHNP 37

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.8-1 Post-L OCA IRW ST Ch em istry Sh ort-T erm DB A L ong-T erm DB A

( Ac c ident Initiation up to 4 h ours) ( 4 h ours up to 30 day s) 4,400 p p m b oron as H3B O3 4,400 p p m b oron as H3B O3 0 - 50 p p m h y draz ine as N2H4 0 - 50 p p m h y draz ine as N2H4 4 p H 10 7.0 p H 8.5 T ri-sodium p h osp h ate as b uf f ering agent KEPCO & KHNP 38

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.8-2 M aterial Potential l y Produc ed Corrosion Produc ts Sub m erged Pool U n-sub m erged M aterial 2 2 2 2 Rem ark Z one ( m / f t ) Sp ray Z one ( m / f t )

1. Conc rete 193.89 / 2,087 674.20 / 7,257

2. Al um inum N/ A 216.09 / 2,326

( 1)

HV AC Eq uip m ent N/ A 154.87 / 1,667

- 4 Reac tor Containm ent Fan Cool ers

- 4 SG Enc l osure Rec irc ul ation Fans

- 4 Annul us Area Rec irc ul ation Fans

- Duc t Insul ation Ex -c ore Detec tors N/ A 0.25 / 2.67 Ref uel ing Eq uip m ent N/ A 12.08 / 130 CEDM Cool ing Fan N/ A 23.24 / 250.2 Surveil l anc e Cap sul e N/ A 22.30 / 240

- Retrieval T ool

- Rem ote Positioning T ool POSRV SIEKA-Ac tuators N/ A 3.36 / 36.2 Note :

( 1) Considering unc ertainty of duc t insul ation area, 10% m argin is added b ased on th e engineering j udgm ent.

KEPCO & KHNP 39

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.8-3 Inp ut Data f or W CAP-16530-NP Ch em ic al Produc t Form ation Class M aterial Amount Notes 3

Cool ant Sum p Pool V ol um e ( f t ) 89,728 2

Al um inum Sub m erged ( f t ) 0 Al um inum Sub m erged ( l b m ) 10,000,000 M etal l ic Al um inum 2

Al um inum Not-Sub m erged ( f t ) 2,326 Al um inum Not-Sub m erged ( l b m ) 10,000,000 3

Cal c ium Sil ic ate Insul ation( f t ) 0 3

Asb estos Insul ation ( f t ) 0 Cal c ium Sil ic ate 3

Kay l o Insul ation ( f t ) 0 3

U nib estos Insul ation ( f t ) 0 3

Fib ergl ass Insul ation ( f t ) 6.25 3

NU KON ( f t ) 0 E-gl ass 3

T em p -M at ( f t ) 0 3

T h erm al W rap ( f t ) 0 3

M ic roth erm (ft) 0 Sil ic a Pow der 3

M in-K ( f t ) 0 3

M in-W ool ( f t ) 0 M ineral W ool 3

Roc k W ool ( f t ) 0 3

Cerab l ank et ( f t ) 0 3

Fib erFrax Durab l ank et ( f t ) 0 3

Kaow ool ( f t ) 0 Al um inum Sil ic ate 3

M at-Ceram ic ( f t ) 0 3

M ineral Fib er ( f t ) 0 3

PAROC M ineral W ool ( f t ) 0 2

Conc rete Conc rete ( f t ) 9,344 T risodium Fl ag= 0 if no T SP, T risodium Ph osp h ate Hy drate ( l b m ) 1 Ph osp h ate ( T SP) 3 b uf f ering agent Interam Interam (ft) 0 KEPCO & KHNP 40

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.8-4 W CAP-16530 Resul ts Sum m ary Com p onent Q uantity ( k g / l b m )

Al um inum ox y -h y drox ide 153.6 / 338.7 Sodium al um inum sil ic ate 4.36 / 9.60 Cal c ium p h osp h ate 0.71 / 1.56 KEPCO & KHNP 41

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.8-5 Resul ts f or th e APR1400, M ax im um W ater V ol um e, M inim um ECCS Fl ow Interval Start of End of Average Average NaAlSi3O8 AlOOH Ca3(PO4)2 Duration Interval Interval Interval T emp Precipitate Precipitate Precipitate (min) (hrs) (hrs) pH (° F) (k g) (k g) (k g) 2.3 0.00 0.0 10 126.1 0.00 0.7 0.00 1.7 0.04 0.1 10 132.8 0.00 1.2 0.00 1.7 0.07 0.1 10 137.1 0.00 1.8 0.00 3.3 0.10 0.2 10 143.8 0.00 2.9 0.00 4.2 0.15 0.2 10 152.5 0.01 4.2 0.00 6.7 0.22 0.3 10 163.6 0.01 6.0 0.00 10.1 0.33 0.5 10 178.3 0.03 8.2 0.01 14.9 0.50 0.8 10 196.6 0.07 11.0 0.01 21.8 0.75 1.1 10 215.0 0.15 14.7 0.02 30.0 1.11 1.6 10 229.7 0.32 19.3 0.04 36.5 1.61 2.2 10 239.5 0.56 24.7 0.06 66.7 2.22 3.3 10 245.6 1.08 34.7 0.09 40.0 3.33 4.0 9.25 248.7 1.33 37.8 0.11 45.0 4.00 4.8 8.5 249.3 1.54 39.7 0.14 165.1 4.75 7.5 8.5 248.4 2.31 46.3 0.22 200.2 7.50 10.8 8.5 244.7 3.17 53.3 0.32 266.9 10.84 15.3 8.5 237.9 4.16 60.6 0.39 417.1 15.29 22.2 8.5 228.1 4.16 68.8 0.40 665.7 22.24 33.3 8.5 216.6 4.16 77.4 0.41 1000.2 33.33 50.0 8.5 205.3 4.17 85.2 0.42 1166.9 50.00 69.5 8.5 195.9 4.18 91.1 0.43 2167.2 69.45 105.6 8.5 186.7 4.19 98.0 0.45 2833.6 105.57 152.8 8.5 177.0 4.21 104.5 0.48 4167.3 152.80 222.3 8.5 168.5 4.23 112.4 0.51 6664.8 222.25 333.3 8.5 161.4 4.26 123.3 0.56 3166.8 333.33 386.1 8.5 157.3 4.27 128.0 0.58 2833.4 386.11 433.3 8.5 155.4 4.28 132.0 0.60 2833.4 433.34 480.6 8.5 153.7 4.30 135.9 0.62 2833.4 480.56 527.8 8.5 152.0 4.31 139.6 0.64 2833.4 527.78 575.0 8.5 150.4 4.32 143.2 0.65 2833.4 575.00 622.2 8.5 149.3 4.33 146.8 0.67 2833.4 622.23 669.5 8.5 148.6 4.34 150.2 0.69 2833.4 669.45 716.7 8.5 147.8 4.36 153.6 0.71 KEPCO & KHNP 42

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 3.9-1 U p stream Ef f ec ts on Hol dup V ol um e 3

V ol um e Sourc e V ol um e ( m / gal )

[ 1] H oldup V olume on the w ay to the IRWST

- Containm ent sp ray susp ended w ater in th e c ontainm ent atm osp h ere 3.13 / 826

- Containm ent sp ray steam w ater 170.69 / 45,092

- Initial f il l ing w ater f or SI sy stem and CS sy stem p ip e 30.58 / 8,078

- W ater stream on th e El . 100 f t f l oor 229.61 / 60,656

- W ater stream on th e f l oor of ref uel ing c avity 42.36 / 11,190

( 1)

- M isc el l aneous h ol dup vol um e 140.01 / 36,987 Sub total [ 1] 616.37 / 162, 829

[ 2] Inactive Pool V olume

- HV T vol um e 212.29 / 56,080

- Reac tor c avity and ICI c avity vol um e 621.53 / 164,192

- Containm ent drain sum p vol um e 11.78 / 3,112

- ICI c avity sum p vol um e 3.40 / 898 Sub total [ 2] 849.00 / 224, 282 Note :

( 1) T h e m isc el l aneous h ol dup vol um e is w ater vol um e h ol dup el sew h ere in th e reac tor b uil ding ( eg., w ater on h oriz ontal surf ac e area b ef ore c asc ading th rough op enings on its w ay b ac k to th e IRW ST ( assum e f l oor drains are c l ogged) , f il m of w ater in vertic al surf ac es of c onc rete struc tures, f il m of w ater on side surf ac e of eq uip m ent, and p uddl es trap p ed on top of th e c onc rete struc ture and eq uip m ent) .

KEPCO & KHNP 43

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 3.2-1 Sectional V iew of the Z OI f or RCS H ot Leg Line Break KEPCO & KHNP 44

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 3.2-2 Sectional V iew of the Z OI f or RCS Cold Leg Line Break KEPCO & KHNP 45

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 3.2-3 Sectional V iew of the Z OI f or M ain Steam Line Break KEPCO & KHNP 46

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 3.5-1 IRWST Sump Strainer Plan and Elevation V iew KEPCO & KHNP 47

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure 3.6-1 Schematic Flow Diagram of SI System KEPCO & KHNP 48

AB RCB IRW ST RET U RN AIR T EST & FL U SHING CONNECT ION KEPCO & KHNP FL ,L C MAIN SPRAY M

V 007 NOZZLE L C V 1014 V 1013 RINGS REFU EL ING POOL L C V 1011 AIR T EST &

FL U SHING CONNECT ION FL ,L C MAIN SPRAY

< DIV ISION I> M V 005 NOZZLE RINGS M M IRW ST L O Design Features to Address GSI-191 V 1001 FL ,L O FL ,L C V 1007 Figure 3.6-2 V 1003 V 001 V 003 CSS HX AUX. SPRAY H X 01A NOZZLE RINGS CSS PUMP SC PP01A HEAT EX CHANGER IRW ST RET U RN Schematic Flow FL ,L C M

V 008 CSS PUMP MINIFLOW HX H X 02A Non-Proprietary REFU EL ING POOL L C V 1012 AIR T EST &

FL U SHING CONNECT ION FL ,L C MAIN SPRAY

< DIV ISION II> M V 006 NOZZLE RINGS M M IRW ST V 1002 L O FL ,L O FL ,L C V 1008 V 1004 V 002 V 004 CSS HX AUX. SPRAY H X 01B NOZZLE RINGS Diagram of CS System CSS PUMP SC PP01B HEAT EX CHANGER CSS PUMP MINIFLOW HX H X 02B APR1400-E-N-NR-14001-NP, Rev.3 49

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 70.0 400 60.0 Containm ent p ressure 350 50.0 ( Containm ent Pr.)

43.24 p sia @ 16,007 sec 300 o

Pressure ( p sia) 40.0

( IRW ST w ater, T )

T em p erature ( F) m ax 246.47 oF @ 16,007 sec 250 30.0 200 20.0

( Saturation Pr. @ w ater T m ax

)

28.03 p sia @ 246.47 oF 150 10.0 IRW ST w ater tem p erature 0.0 100 10-1 100 101 102 103 104 105 106 107 T im e ( sec )

Figure 3.6-3 Containment Pressure and T emperature vs. T ime f or Long-T erm Phase (Doub le-ended Discharge Leg Slot Break w ith M inimum ECCS Flow )

KEPCO & KHNP 50

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure 3.6-4 Limiting SI pump NPSH vs. T ime KEPCO & KHNP 51

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure 3.6-5 Limiting CS pump NPSH vs. T ime KEPCO & KHNP 52

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 10.5 10 9.5 9

pH 8.5 8

7.5 7

0 1 10 100 1,000 10,000 100,000 Time (Min.)

Figure 3.8-1 IRWST and Containment Spray pH vs. T ime Curve used in Chemical Ef f ects Analysis KEPCO & KHNP 53

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 3.9-1 Schematic of Containment Spray/ Blow dow n Return Pathw ays KEPCO & KHNP 54

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 3.9-2 Schematic of Potential Water T raps in Containment KEPCO & KHNP 55

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 M AX IM U M WAT ER LEV EL 93.4 f t H oldup V olume T ec h Sp ec . - ICI Cavity and Hol dup V ol um e T ank

- Containm ent sp ray susp ended w ater in th e 7 Day Insp ec tion L evel NORM AL WAT ER LEV EL 93.0 f t c ontainm ent atm osp h ere

- Containm ent sp ray steam w ater 627,000 gal - Initial f il l ing w ater f or SI and CS sy stem s p ip e 92.6 f t - W ater stream on th e el evation 100 f t 0 in f l oor

- W ater stream on th e f l oor of ref uel ing p ool M INIM U M WAT ER LEV EL

- M isc el l aneous h ol d-up vol um e DU RING NORM AL OPERAT ION

- Containm ent drain sum p vol um e

- ICI c avity sum p vol um e 262,388 gal M INIM U M WAT ER LEV EL FOR ESF OPERAT ION 86 f t T otal H oldup V olume : 387, 111 gal 53 f t 81 f t 78 f t ESF SU M P

( 4) 69.75 f t ESF PU M P Figure 3.9-3 Schematic Diagram f or IRWST Water V olume KEPCO & KHNP 56

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 4 DOWNSTREAM EFFECTS T h e req uirem ents of NRC RG 1.82, Rev. 4 ( Ref erenc e [ 1-1] ) , state th at p otential IRW ST sum p strainer dow nstream f l ow restric tions due to deb ris b l oc k age sh al l b e eval uated to ensure ap p rop riate l ong-term rec irc ul ation c ool ing, c ontainm ent c ool ing, and c ontainm ent p ressure c ontrol c ap ab il ities.

T o eval uate th e dow nstream c om p onents, a determ ination of th e q uantity of th e b y p ass deb ris is nec essary . Given th at th e strainer is f ab ric ated f rom p erf orated p l ate, th e strainer sh oul d b e siz ed l arge enough to p roduc e an ac c ep tab l e p ressure drop f or th e deb ris l oad, b ut not ex c essivel y l arge th at it p asses too m uc h b y p ass deb ris.

T h e k ey m aterial in th e b l oc k age of dow nstream c om p onents is th e f ib rous deb ris. W h il e p artic ul ates and c h em ic al p rec ip itates ef f ec ts c an b ec om e entrained in th e rec irc ul ation f l ow p ath , w ith out any f ib rous m aterial s, a deb ris b ed and b l oc k age p oint is dif f ic ul t to f orm . T h e total f ib rous deb ris l oad at th e strainer h as b een estab l ish ed at 6.80 k g ( 15 l b m ) of l atent f ib er.

2 T h ere are f our indep endent 55.74 m ( 600 f t² ) ECCS strainer trains in th e APR1400, and th e c onservative sc enario f or b y p ass is assum ed th at al l p um p s are op erating as designed and no singl e f ail ure.

Sh utdow n c ool ing p um p s ( SCPs) are not op erational at th is tim e.

4.1 Strainer Bypass T esting T o estab l ish th e q uantity of f ib rous deb ris th at c oul d p otential l y p enetrate ( b y p ass) th e strainer, p rototy p e testing is p erf orm ed. T h e testing is p erf orm ed w ith onl y f ib rous deb ris as adding p artic ul ates m ay reduc e th e am ount of b y p ass deb ris due to c l ogging at th e strainer. During th e f uel b l oc k age testing, vary ing am ounts of p artic ul ate to f ib er ratios c an b e ex p l ored to determ ine th e l im iting am ount of p artic ul ate ( up to th e m ax im um am ount) . Additional l y , unl ik e h ead l oss testing, th e m ost c onservative ap p roac h w ith b y p ass testing is to assum e al l sum p strainers are ac tive running at th e m ax im um f l ow rates sinc e it stands to reason th at m ore m ass f l ow rate and m ore p erf orated p l ates c auses m ore b y p ass. T h e detail test p l an is p rovided in APR1400 IRW ST ECCS Sum p Strainer B y p ass T est Pl an ( Ref erenc e [ 4-1] ) and th e test resul t is p rovided in Ap p endix C of th is rep ort.

T h e test m easured th e b y p ass of th e m ax im um f ib er l oad of 6.80 k g ( 15 l b m ) sc al ed to th e p rototy p e 2 2 strainer area of 6.98 m ( 75.1 f t ) . B atc h es are tested at a siz e distrib ution of 100% f ines to m ax im iz e b y p ass. Sinc e al l f our strainers c oul d b e ac tive, th e deb ris l oad is distrib uted to eac h of th e strainers b ased on f l ow rate. T h eref ore, tw o of th e strainers get 25,211 L / m in / 59,772 L / m in ( 6,660 gp m / 15,790 gp m ) x 6.80 k g ( 15 l b m ) , or 2.87 k g ( 6.33 l b m ) of deb ris and tw o of th e strainers get 4,675 L / m in / 59,772 L / m in ( 1,235 gp m / 15,790 gp m ) x 6.80 k g ( 15 l b m ) , or 0.53 k g ( 1.17 l b m ) of deb ris. Strainer f l ow rates and deb ris l oads are inc l uded in T ab l e 4.1-1.

Sinc e onl y th e h igh er f l ow rate strainer is tested, th e f ol l ow ing f our b atc h es of 181.2 g ( 0.40 l b m ) ( 0.0265 in.

eq uival ent th ic k ness) are added to th e test to p rovide b y p ass p erf orm anc e data of th e test strainer over a range f ib er th ic k ness. It sh oul d b e noted th at th e f our b atc h es p roduc es tw ic e th e req uired deb ris l oad of 0.36 k g ( 0.79 l b m ) .

A singl e b y p ass test is run w ith f our b atc h es of f ines rep resenting l atent deb ris added. Fil ters are instal l ed dow nstream of th e p rototy p e strainer to c ol l ec t b y p assed f ib er. Fil ters are instal l ed dow nstream of th e p rototy p e strainer to c ol l ec t b y p assed f ib er. No f ib er is al l ow ed to rec irc ul ate b ac k into th e tank and f l ow stream . A new f il ter is val ved in and th e ol d val ved out f or eac h b atc h or f ib er addition. T h e tim e b etw een eac h f ib er addition is ap p rox im atel y seven p ool turnovers. T h e resul ting b y p ass f ib er w eigh ts KEPCO & KHNP 57

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 are p resented in T ab l e 4.1-2.

T o determ ine th e p l ant strainer b y p ass deb ris, th e c um ul ative q uantity of b y p ass deb ris f rom th e p rototy p e test is sc al ed b y a ratio of th e p l ant strainer to th e p rototy p e strainer ( 600/ 75.1 = 8.0) . T h e c um ul ative b y p ass q uantities f or deb ris l oads are p resented in T ab l e 4.1-2. T h e total b y p ass deb ris is th e sum of th e b y p ass deb ris f or al l ac tive strainers and p resented in T ab l e 4.1-3.

T otal b y p ass deb ris f or th e APR1400 w ith 6.80 k g ( 15 l b m ) of l atent f ib er is 1.67 k g ( 3.68 l b m ) .

4.2 Ex -V essel Dow nstream Ef f ects T h e ob j ec tive of ex -vessel dow nstream ef f ec ts eval uation is to assess th e sy stem s and c om p onents of th e APR 1400 em ergenc y c ore c ool ing sy stem ( ECCS) and th e c ontainm ent sp ray sy stem ( CSS) to ensure th at th ese sy stem s are designed to b e op erab l e under p ost l oss-of -c ool ant ac c ident c onditions ( L OCA) .

4.2.1 System Descriptions 4.2.1.1 Emergency Core Cooling System T h e ECCS is designed to p erf orm th e f ol l ow ing m aj or f unc tions:

1) Inj ec t b orated w ater into th e reac tor c ool ant sy stem ( RCS) th rough direc t vessel inj ec tion ( DV I) noz z l es to f l ood and c ool th e c ore f ol l ow ing a L OCA, th us p reventing a signif ic ant am ount of c l adding f ail ure al ong w ith sub seq uent rel ease of f ission p roduc ts into th e c ontainm ent and m aintaining th e c ore sub c ritic al

2) Provide rem oval of h eat f orm th e c ore f or ex tended p eriods of tim e f ol l ow ing a L OCA

3) Inj ec t b orated w ater into th e RCS to inc rease sh utdow n m argin f ol l ow ing a rap id c ool dow n of th e sy stem due to a steam l ine b reak

4) Prevent b oron p rec ip itation in th e RCS during l ong-term m ode of op eration

5) Provide inventory m ak eup and b oration f or reac tivity c ontrol during a saf e sh utdow n if nec essary

6) Provide f eed f l ow f or f eed-and-b l eed op eration in c onj unc tion w ith p ressuriz er ( PZ R) p il ot op erated saf ety rel ief val ves ( POSRV s) to rem ove c ore dec ay h eat during b ey ond design b asis event of a total l oss of f eed w ater to steam generators T h e ECCS c onsists of f our m ec h anic al l y sep arate trains, f our saf ety inj ec tion tank s ( SIT s) , and assoc iated val ves, p ip ing, instrum entation. Eac h train c ontains one SI p um p , one SIT , and assoc iated suc tion and disc h arge p ath s. T h e p um p s tak e suc tion f rom th e in-c ontainm ent ref uel ing w ater storage tank ( IRW ST ) .

M otor-op erated val ves and p um p in eac h train rec eive p ow er f rom eith er th e norm al p ow er sourc e or th e em ergenc y diesel generators. Pow er c onnec tions are th rough f our indep endent el ec tric al trains w ith eac h train p roviding p ow er to one b us. In th e event of a L OCA, in c onj unc tion w ith a singl e f ail ure in th e el ec tric al sup p l y , th e f l ow f rom at l east tw o saf ety inj ec tion p um p s ( SIPs) is avail ab l e f or c ore p rotec tion.

One indep endent el ec tric al train, as desc rib ed ab ove, sup p l ies p ow er to th ree SIPs and assoc iated val ves.

Oth er indep endent el ec tric al trains sup p l y p ow er to th e rem aining th ree SIPs and assoc iated val ves.

Eac h SIP disc h arge l ine is c onnec ted to th e DV I noz z l e or th e DV I noz z l e/ h ot l eg ( HL ) . T h e ECCS l ines 1&2 inj ec t th e b orated w ater to RCS th rough th e DV I noz z l es and th e ECCS l ines 3&4 inj ec t th e b orated w ater to th e DV I noz z l es or HL inj ec tion l ines f or th e l ong-term m ode. T h is is il l ustrated in Figure 3.6-1.

KEPCO & KHNP 58

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T h e ECCS l ines c ontain th e ECCS l ine isol ation val ves and ECCS HL isol ation val ves.

Fl ow restric ting devic es in th e disc h arge l ine of th e SIPs p revent th e assoc iated p um p f orm ex c eeding runout f l ow f ol l ow ing a l arge b reak L OCA. T h e saf ety inj ec tion ( SI) isol ation val ves are norm al l y c l osed during p ow er op eration. T h e rem ainder of th e ECCS is al igned f or inj ec tion, b ut does not op erate.

2 W h enever p ressuriz er p ressure is ab ove 42.18 k g/ c m ( 600 p sia) , th e SIT s are isol ated f rom th e RCS b y onl y tw o c h ec k val ves in series. If RCS p ressure sh oul d f al l b el ow SIT p ressure, th e tank s w il l b egin to disc h arge b orated w ater into th e RCS. T h us th e tank s c om p rise an ex trem el y rel iab l e p assive c ore f l ooding sy stem . SIPs are used to inj ec t b orated w ater ( f eed f unc tion) into th e RCS and restore th e RCS l iq uid inventory w h en th e RCS p ressure dec reases rap idl y b y op ening POSRV s during b ey ond design b asis ac c ident ( DB A) of a total l oss of f eedw ater to steam generators ( SGs) .

4.2.1.2 Containment Spray System T h e CSS is designed to p erf orm th e f ol l ow ing m aj or f unc tions:

1) Reduc e th e c ontainm ent atm osp h ere p ressure and tem p erature b el ow c ontainm ent design l im its w ith m argin in th e event of a p ostul ated L OCA or m ain steam l ine b reak ( M SL B ) inside c ontainm ent, b y rem oving h eat f rom c ontainm ent atm osp h ere.

2) L im it airb orne iodine and p artic ul ate f ission p roduc t inventory in th e c ontainm ent atm osp h ere in th e event of a p ostul ated L OCA.

3) Provide a b ac k up to th e sh utdow n c ool ing sy stem ( SCS) f or residual h eat rem oval and f or c ool ing of th e IRW ST during p ost-ac c ident f eed and b l eed op erations util iz ing th e saf ety inj ec tion sy stem

( SIS) and POSRV s.

4) Provide p ost-ac c ident c ontainm ent atm osp h ere m ix ing to p revent h igh l oc al h y drogen c onc entration w ith in th e c ontainm ent.

5) Ensure a p ost-L OCA sp ray w ater c h em istry c ondition w ith in a p rop er p H range w h ic h is req uired f or h y drogen c ontrol , m aterial c om p atib il ity and l ong-term iodine c ontrol against re-evol ution.

6) Provide p ost-ac c ident l ong-term c ool ing of th e IRW ST to rem ove th e dec ay h eat onl y w h en th e c ontainm ent sp ray op eration via sp ray h eader is not avail ab l e to p rotec t th e eq uip m ent l oc ated inside th e c ontainm ent af ter 30 day s f ol l ow ing th e ac c ident.

T h e CSS is an engineered saf ety f eature ( ESF) designed to rem ove h eat and f ission p roduc ts f rom th e c ontainm ent atm osp h ere in th e event of a L OCA and a m ain steam or f eedw ater l ine b reak inside c ontainm ent and th ereb y to l im it th e l eak age of airb orne ac tivity f rom th e c ontainm ent.

T h e CSS is al so designed to m aintain p ost-L OCA IRW ST w ater p H l evel b etw een 7.0 and 8.5 f ol l ow ing a L OCA. Post-ac c ident p H c ontrol of th e IRW ST w ater is p rovided using tri-sodium p h osp h ate ( T SP) th at is stored in th e h ol dup vol um e tank ( HV T ) of th e in-c ontainm ent w ater storage sy stem ( IW SS) .

T h e CSS c onsists of tw o redundant 100% c ap ac ity trains. Eac h train inc l udes a c ontainm ent sp ray p um p

( CSP) , a c ontainm ent sp ray h eat ex c h anger ( CSHX ) , a c ontainm ent sp ray ( CS) m ini-f l ow h eat ex c h anger, a m ain sp ray h eader w ith noz z l es, an aux il iary sp ray h eader w ith noz z l es, and assoc iated val ves, p ip ing and instrum entation.

KEPCO & KHNP 59

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T h e CSS p rovides sp ray s of w ater to th e c ontainm ent atm osp h ere f rom th e up p er regions of th e c ontainm ent and b el ow th e op erating f l oor. T h e sp ray f l ow is p rovided b y th e CSPs w h ic h tak e suc tion f rom th e IRW ST . T h e CSPs start up on th e rec eip t of a SIAS or a CSAS. T h e CSPs disc h arge w ater th rough th e CSHX s and th e sp ray h eader isol ation val ves to th eir resp ec tive sp ray noz z l e h eaders, th en into th e c ontainm ent atm osp h ere. Sp ray f l ow to th e c ontainm ent sp ray h eaders is not p rovided until a c ontainm ent sp ray ac tuation signal ( CSAS) autom atic al l y op ens th e c ontainm ent sp ray h eader isol ation val ves. T h e m ain sp ray h eaders are l oc ated in th e up p er p art of th e reac tor c ontainm ent b uil ding to al l ow th e f al l ing sp ray drop l ets to reac h th erm al eq uil ib rium state w ith th e steam -air atm osp h ere. Condensation of th e steam b y th e f al l ing sp ray resul ts in a reduc tion of c ontainm ent p ressure and tem p erature. T h e m ain sp ray al so ac ts to m ix th e c ontainm ent atm osp h ere b y direc t and indirec t c onvec tive f l ow s, and al so ac ts to ab sorb and retain c ertain radioisotop es w h ic h m ay b e p resent in a p ost-ac c ident environm ent.

T h e aux il iary sp ray h eaders f rom eac h train are l oc ated b el ow th e op erating f l oor and h eader noz z l es are arranged to p rom ote m ix ing of th e c ontainm ent atm osp h ere w ith in th e aux il iary sp ray ed region and b etw een th e annul us area b el ow th e op erating f l oor and th e m ain sp ray ed region ab ove th e op erating f l oor.

T h e CSPs are designed to b e f unc tional l y interc h angeab l e w ith th e sh utdow n c ool ing p um p s ( SCPs) .

T h ough not req uired f or norm al op eration or ac c ident m itigation, interc h angeab il ity of th e p um p s al l ow s th e CSPs to b ac k up th e SCPs w h en th e CSPs are not needed f or th eir req uisite f unc tion ( i.e., during ref uel ing or l ong term c ool ing op eration) . In addition, th e CSPs and CSHX s c an b e used as a b ac k up to th e SCPs and h eat ex c h angers to p rovide c ool ing of th e IRW ST during p ost-ac c ident f eed and b l eed op erations w h en th e steam generators are not avail ab l e to c ool th e RCS. T h e suc tion and disc h arge l ines of th e CSP and th e SCP are interc onnec ted w ith a val ve.

A m inim um f l ow l ine is p rovided on eac h CSP disc h arge l ine, and is c onnec ted to th e CSP suc tion l ine.

T h ese m inim um f l ow p ath s ensure th at th e CSPs are not deadh eaded if th e CSPs are inadvertentl y run against a c l osed sy stem .

4.2.2 Design Inputs/ Evaluation Assumptions 4.2.2.1 LOCA Scenarios Dow nstream ef f ec t eval uation of th e ECCS and CSS op eration inc l udes sm al l b reak L OCA ( SB L OCA) and l arge b reak L OCA ( L B L OCA) c onditions.

1) L B L OCA sc enario T h e l im iting L B L OCA is assum ed to a doub l e ended guil l otine c ol d l eg ( CL ) l ine b reak at th e disc h arge of th e reac tor c ool ant p um p ( RCP) .

During th is event th e SIT s disc h arge to th e RCS as soon as RCS p ressure dec reases b el ow SIT p ressure. As a c onservative estim ate in th e c al c ul ation of th e ref l ood p ortion of th e ac c ident, no c redit is tak en f or SIP f l ow until th e SIT s em p ty .

2) SB L OCA sc enario T h e m ost l im iting SB L OCA is assum ed to oc c ur in a DV I l ine b reak L OCA.

T h e w orst c ase SB L OCA assum es som e tim e del ay b ef ore p um p ed f l ow reac h es th e c ore. For KEPCO & KHNP 60

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 th e l arger range of sm al l b reak s, th e rate of b l ow dow n is suc h th at th e inc rease in f uel c l ad tem p erature is term inated m ainl y b y th e SIT s, w ith p um p ed f l ow th en p roviding c ontinued c ool ing.

As b reak siz e c ontinues to dec rease, th e SIT s and an SIP b oth p l ay a p art in term inating th e rise in c l ad tem p erature.

Ab ove p roc ess ( b l ow dow n, p assive inj ec tion, and rec overy ) tak es l onger tim e p eriod c om p ared w ith L B L OCA and th e duration dep ends on th e b reak siz e and th e p erf orm anc e of th e ECCS.

For th is eval uation, th e SB L OCA is b ounded b y th e L B L OCA and p ost-L OCA l ong-term c ool ing.

T h e deb ris q uantity and th e ECCS f l ow s during th e SB L OCA are c onsidered m uc h sm al l er th an during th e L B L OCA.

T h eref ore, th e SB L OCA sc enario in th e eval uation of th e dow nstream ef f ec t is b ounded b y th e c onditions of th e L B L OCA sc enario.

4.2.2.2 M ission T ime M ission tim e rep resents th e m ax im um p eriod of tim e f or w h ic h a Sy stem , Struc ture or Com p onent rem ains to p erf orm th eir saf ety f unc tion. It is th e ac c ident anal y sis c redit tim e.

For th is eval uation, th e m ission tim e of th e dow nstream ef f ec t eval uation is def ined as 30 day s f ol l ow ing th e Ch ap ter 15 of th e DCD ( Ref erenc e [ 3-1] ) .

4.2.2.3 Components of Interest T ab l e 4.2-1 l ists th e ECCS and CSS c om p onents in th e dow nstream ef f ec ts eval uation. T h ese c om p onents are in th e ECCS and CSS f l ow p ath during SB L OCA and L B L OCA op erations.

4.2.2.4 Post-LOCA Fluid Constituents Deb ris in th e p ost-L OCA f l uid c onsists of l atent deb ris ( p artic ul ate and f ib er) , c oating p artic l es ( i.e., ep ox y ) ,

insul ation m aterial s, and m isc el l aneous deb ris. M isc el l aneous deb ris inc l udes m aterial s p l ac ed inside c ontainm ent f or an op erational , m aintenanc e, or engineering p urp ose. M aterial s inc l ude tap e, tags, stic k ers, adh esive l ab el s used f or c om p onent identif ic ation, f ire b arrier m aterial s, and oth er m aterial s ( e.g.,

rop e, f ire h oses, ventil ation f il ters, p l astic sh eeting) .

Deb ris siz es are c l assif ied as p artic ul ates, f ines, and l arge p iec es. T h e siz es in T ab l e 4.2-2 are b ased on th e f ol l ow ing:

1) T h is eval uation c onservativel y assum es th at 100% of th e p artic ul ates w il l b y p ass th e IRW ST sum p strainers. T h eref ore, it is reasonab l e to assert th at th e siz e of th e p artic ul ate deb ris is l ess th an

( or eq ual to) th e p erf orated p l ate h ol e siz e of th e IRW ST sum p strainers, 2.38 m m ( 0.094 inc h ) .

2) Fines are def ined as deb ris m aterial s th at are l ess th an 101.6 m m ( 4 inc h ) b y 101.6 m m ( 4 inc h ) ,

b ased on NEI 04-07 V ol um e 1, Sub sec tion 3.6.3 ( Ref erenc e [ 3-2] ) .

3) L arge p iec es are def ined as deb ris m aterial s th at are greater th an 101.6 m m ( 4 inc h ) , b ased on KEPCO & KHNP 61

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 NEI 04-07 V ol um e 1, Sub sec tion 3.6.3 ( Ref erenc e [ 3-2] ) ..

T h e total am ount of deb ris generated during an L B L OCA is estim ated in Ap p endix B of th is rep ort and sum m ariz ed in T ab l e 4.2-3. T h e am ount of ref l ec tive m etal l ic insul ation ( RM I) l isted in T ab l e 4.2-3 is b ased on a siz e distrib ution of 75% of sm al l f ines and 25% f or l arge p iec es.

T h e am ount of deb ris th at p asses th rough th e IRW ST sum p strainer dep ends on th e siz e of th e strainer h ol e, ratio of op en to c l osed area of th e strainer, th e f l uid ap p roac h vel oc ity to th e strainer, and th e strainer geom etry . T h is eval uation assum es th at L B L OCA deb ris m aterial s th at are l ess th an or eq ual to th e p erf orated p l ate h ol e siz e 2.38 m m ( 0.094 inc h ) of th e IRW ST sum p strainers w il l b y p ass th e sum p strainer. As a resul t, th e ECCS w il l ingest 100% of th e c oating p artic ul ates.

M isc el l aneous deb ris m aterial s are l arge p iec es w ith a deb ris siz e range th at is signif ic antl y greater th an th e p erf orated p l ate h ol e siz e sum p strainer. As a resul t, th e ECCS w il l not ingest m isc el l aneous deb ris m aterial s.

B y p ass testing of th e l atent deb ris y iel ded a f ib er b y p ass p erc entage of l ess th an 25% ( see Ap p endix D) .

T h is eval uation uses b ounding b y p ass p erc entages of 100% f or l atent p artic ul ates ( i.e., dust and dirt) .

T h e b y p ass p erc entage f or l atent f ib er uses a c onservative of 100% . T h e ac tual b y p ass p erc ent f or l atent f ib er is eval uated b y q ual if ied test resul ts c onduc ted sp ec if ic to th e APR1400 p l ant c onditions. T h e detail test p l an is p rovided in Ref erenc e [ 4-1] and th e test resul t is p rovided in Ap p endix D of th is rep ort. B ased on th e resul ts of b y p ass testing, th e ac tual b y p ass p erc entage f or l atent f ib er is ap p rox im atel y 25% .

Resul ts of th e NRC deb ris generation test doc um ented in NU REG/ CR-6808 ( Ref erenc e [ 4-2] ) sh ow th at RM I deb ris siz e distrib ution ranges f rom 6.35 m m ( 0.25 inc h ) to 152.4 m m ( 6 inc h ) . RM I deb ris w il l not b y p ass th e sum p sc reens and enter th e ECCS b ec ause th e siz e of th e RM I deb ris is greater th an th e p erf orated p l ate h ol e siz e sum p strainer. As a resul t, th is eval uation assum es no RM I b y p asses th rough th e sum p strainer.

Ref erenc e inf orm ation ( Ref erenc e [ 3-12] ) on m aterial p rop erties to eval uate th e w ear rate of th e c om p onents is p rovided in T ab l e 4.2-8.

4.2.2.5 ECCS Flow Rate and Flow V elocity T h e APR1400 is a f ix ed resistanc e sy stem under val ve w ide-op en c onditions. Em ergenc y Op erating Proc edures do al l ow f or op erator ac tion to th rottl e f l ow b ased on m ain c ontrol room ( M CR) indic ation.

T h e range of op eration is th eref ore assum ed to b e f rom sh utof f h ead c onditions to runout c onditions.

T o eval uate deb ris settl em ent and c om p onent w ear during an L B L OCA, th is eval uation c onservativel y assum es ECCS and CSS f l ow rates ranging f rom sh utof f h ead c onditions to runout c onditions.

Saf ety Inj ec tion Pum p f l ow is assum ed to b e 303 L / m in ( 80 gp m ) f or eval uating deb ris settl em ent in th e SIS. Fl ow is assum ed to b e 6,057 L / m in ( 1,600 gp m ) f or c om p onent w ear rate eval uations. Engineering design range of f l ow is 397 L / m in ( 105 gp m ) at sh utof f and 4,675 L / m in ( 1,235 gp m ) at runout.

CS p um p f l ow is assum ed to b e 1,514 L / m in ( 400 gp m ) f or eval uating deb ris settl em ent in th e CSS. Fl ow is assum ed to b e 27,255 L / m in ( 7,200 gp m ) f or c om p onent w ear rate eval uations. Engineering design range of f l ow is 1,817 L / m in ( 480 gp m ) at sh utof f and 24,605 L / m in ( 6,500 gp m ) at runout. T h e c om p onent w ear rate eval uation is detail ed in Sub sec tion 4.2.3.1.

KEPCO & KHNP 62

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T h e term inal settl ing vel oc ities of th e deb ris sourc e m aterial s are l isted in T ab l e 4.2-4. T h e vel oc ity of th e deb ris in th e p ost-L OCA f l uid is eq ual to th e vel oc ity of th e f l uid. If th e ECCS f l uid vel oc ity is greater th an th e term inal settl ing vel oc ity of th e deb ris, th e deb ris w il l not settl e.

T h e f l ow rate of th e SI and CS p um p s at sh utof f h ead and run-out c onditions w il l b e verif ied during c om p onent p roc urem ent.

4.2.2.6 Summary of Assumptions and Conservatisms Assum p tions and c onservatism s used in th is eval uation are sum m ariz ed as f ol l ow s:

1) Onl y 100% of al l p artic ul ates ( i.e., c oating deb ris, l atent p artic ul ates) and 100% of l atent f ib er are assum ed to p ass th rough th e strainers and enter into th e ECCS and CSS. RM I doesn t b y p ass th rough th e sum p strainer b ec ause th e siz e of th e RM I deb ris is greater th an th e p erf orated p l ate h ol e siz e sum p strainer.

2) SIP f l ow is assum ed to b e 303 L / m in ( 80 gp m ) f or th e p urp ose of c al c ul ating settl ing vel oc ities.

Fl ow is assum ed to b e 6,057 L / m in ( 1,600 gp m ) f or th e p urp ose of c om p onent w ear rate eval uations. Engineering design range of f l ow is 397 L / m in ( 105 gp m ) at sh utof f and 4,675 L / m in

( 1,235 gp m ) at runout.

3) CSP f l ow is assum ed to b e 1,514 L / m in ( 400 gp m ) f or th e p urp oses of c al c ul ating settl ing vel oc ities. Fl ow is assum ed to b e 27,255 L / m in ( 7,200 gp m ) f or th e p urp ose of c om p onent w ear rate eval uations. Engineering design range of f l ow is 1,817 L / m in ( 480 gp m ) at sh utof f and 24,605 L / m in ( 6,500 gp m ) at runout.

4) W ear is c al c ul ated f rom tim e z ero , i.e. start of th e event. W orst c ase f l uid p rop erties are assum ed to b e p resent. T h is assum p tion is c onservative sinc e it does not c redit deb ris transp ort or th e sl ow inc rease of f l uid p rop erties due to l ong term m ix ing.

5) Fl uid vel oc ity th rough a singl e CS h eat ex c h anger tub e is assum ed to b e 4.57 m / s ( 15 f t/ s) . A nom inal design and op erating h eat ex c h anger vel oc ity range is 0.91 to 3.05 m / s ( 3 to 10 f t/ s) .

T h eref ore, th e use of 4.57 m / s ( 15 f t/ s) is c onservative f rom a h eat ex c h anger design p ersp ec tive and b ounds th e h eat ex c h anger design and p roc urem ent sp ec if ic ations.

T ab l e 4.2-5 l ists th e am ount of deb ris in th e p ost-L OCA f l uid ( dow nstream of th e IRW ST sum p strainer) th at w il l b e used f or c onf irm atory tests. T h e am ount of deb ris in th e ECCS during p ost-L OCA op eration is b ased on ab ove assum p tion 1) . T h e am ount of l atent deb ris in T ab l e 4.2-5 is c onservativel y b ased on th e m ax im um am ount of l atent p artic ul ates and 100% of th e m ax im um am ount of f ib er l isted in T ab l e 4.2-3.

T h e siz e range of th e deb ris m aterial s is b ased on ( i) th e assum p tion th at 100% of p artic ul ates w il l b y p ass th e ECCS strainers, and ( ii) guidanc e f rom NEI 04-07 V ol um e 2 Ap p endix V . T h e c onc entration of th e p ost-L OCA f l uid c onstituents is c onservativel y estim ated b ased on th e assum p tion th at th e IRW ST 3

c ontains 946.4 m ( 250,000 gal l ons) of w ater during p ost-L OCA op eration, w h ic h is l ess th an th e m inim um 3

IRW ST w ater vol um e f or ESF op eration of 993.2 m ( 262,388 gal l ons) . Estim ating th e deb ris c onc entration at l ess th an th e ex p ec ted IRW ST vol um e y iel ds a m ore c onc entrated deb ris-l aden f l uid f or c onf irm atory tests, and p roduc es c onservative test resul ts.

KEPCO & KHNP 63

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 4.2.3 ECCS Component Evaluations T h is sec tion eval uates th e ECCS p um p s, h eat ex c h angers, val ves, instrum ent tub es, and p ip ing regarding w ear, b l oc k age, and f oul ing ( h eat ex c h anger) .

4.2.3.1 SI and CS Pump Evaluation T h e SI p um p s are m otor-driven h oriz ontal , m ul tistage, c entrif ugal p um p s w ith m ec h anic al seal s. T h e p um p s are siz ed to del iver 3,085 L / m in ( 815 gp m ) at a disc h arge h ead of 869 m ( 2,850 f t) . T h e CS p um p s are m otor-driven c entrif ugal p um p s w ith m ec h anic al seal s. T h e p um p s are siz ed to del iver 20,536 L / m in

( 5,425 gp m ) ( inc l uding b y p ass f l ow 1,609 L / m in ( 425 gp m ) ) at a disc h arge h ead of 125 m ( 410 f t) . T h e 100% c ap ac ity design f l ow rate is b ased up on a 57.5 L / m in ( 15.2 gp m ) f l ow p er noz z l e.

T h e SI and CS p um p s and assoc iated m ec h anic al seal s w il l b e q ual if ied to op erate w ith th e p ost-L OCA f l uids f or at l east 30 day s in ac c ordanc e w ith ASM E Q M E-1-2007 as endorsed b y RG 1.100 Revision 3. As a p art of q ual if ic ation, th ree asp ec ts of p um p op erab il ity , i.e. h y draul ic p erf orm anc e, m ec h anic al sh af t seal assem b l y p erf orm anc e, and p um p m ec h anic al p erf orm anc e ( vib ration) , are c onsidered in eval uating th e SI and CS p um p s f or op eration w ith deb ris-l aden w ater in ac c ordanc e w ith th e guidanc e of RG 1.82 Revision 4.

4.2.3.2 H eat Ex changer Evaluation T h e CSHX s are used to rem ove h eat f rom th e c ontainm ent atm osp h ere during and af ter an ac c ident.

T h e units are designed to reduc e th e c ontainm ent atm osp h ere p ressure in 24 h ours af ter an ac c ident to h al f of th e c al c ul ated p eak p ressure. T h e CS m inif l ow h eat ex c h angers are used to rem ove h eat generated b y running th e CS p um p w h en op erating at m inif l ow ( i.e., against a c l osed m ain disc h arge p ath or against a b ac k p ressure th at is h igh er th an th e sum of th e p um p suc tion p ressure and total devel op ed p um p h ead) .

T h e CS h eat ex c h angers and CS m inif l ow h eat ex c h angers are sp ec if ied as sh el l and U -tub e units. T h e CS h eat ex c h angers are c om p osed of 31.75 m m ( 1.25 inc h ) OD, B irm ingh am W ire Gauge ( B W G) 18 ( 1.24 m m ( 0.049 inc h ) ) , 304 SS tub es. T h e CS m inif l ow h eat ex c h angers are c om p osed of 22.23 m m ( 0.875 inc h ) OD, B irm ingh am W ire Gauge ( B W G) 18 ( 1.24 m m ( 0.049 inc h ) ) , 304 SS tub es.

T h e h eat ex c h anger p l ugging, f oul ing, w ear, and h eat transf er p erf orm anc e in th e p resenc e of p ost-L OCA deb ris w il l b e eval uated b y th e vendor during th e p roc urem ent p roc ess w ith a c ertif ic ate of c om p l ianc e to p rovide verif ic ation th at th e h eat ex c h anger m eets p roc urem ent sp ec if ic ations. For vel oc ity , a m ax im um tub e vel oc ity of 4.57 m / s ( 15 f t/ s) is assum ed. A nom inal design and op erating h eat ex c h anger vel oc ity range is 0.91 to 3.05 m / s ( 3 to 10 f t/ s) . T h eref ore th e use of 4.57 m / s ( 15 f t/ s) is c onservative f rom a h eat ex c h anger design p ersp ec tive and b ounds th e h eat ex c h anger design and p roc urem ent sp ec if ic ation( s) .

4.2.3.2.1 H eat Ex changer Plugging T h e CS h eat ex c h anger tub es are 31.75 m m ( 1.25 inc h ) OD, 29.26 m m ( 1.152 inc h ) ID, B W G 18 ( 1.24 m m ( 0.049 inc h ) ) . T h e CS m inif l ow h eat ex c h anger tub es are 22.23 m m ( 0.875 inc h ) OD, 19.74 m m

( 0.777 inc h ) ID, B W G 18 ( 1.24 m m ( 0.049 inc h ) ) . T h e p erf orated p l ate h ol e siz e of th e IRW ST sum p strainers is 2.38 m m ( 0.094 inc h ) . T h e h eat ex c h anger tub es are signif ic antl y l arger th an th e l argest ex p ec ted p artic l e siz e. T h eref ore, a h eat ex c h anger tub e w il l not b e p l ugged or b l oc k ed b y p ost-L OCA deb ris. T h e f l ow vel oc ity w ith in a h eat ex c h anger tub e is signif ic antl y greater th an th e term inal settl ing vel oc ity of th e deb ris ( T ab l e 4.2-4) b ec ause th e h eat ex c h anger is designed w ith a tub e f l ow vel oc ity not to KEPCO & KHNP 64

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 b e l ess th an 3 f t/ s to p revent dep osition of susp ended m aterial s in transition areas of h eat ex c h angers, p ip ing, etc . T h eref ore, th e deb ris w il l not settl e in th e h eat ex c h anger tub es.

T h ese c onc l usions are c onsistent w ith th e ref erenc ed NRC Saf ety Eval uation on W CAP-16406-P

( Ref erenc e [ 4-3] ) .

4.2.3.2.2 H eat Ex changer Perf ormance and Wear T h e CS h eat ex c h angers and CS m inif l ow h eat ex c h angers are siz ed and designed w ith a f oul ing f ac tor of 2 2 0.000088 m -K/ W ( 0.0005 h r-f t -° F/ B tu) to m ax im iz e h eat transf er ef f ic ienc y and p erf orm anc e. T h e p ost-L OCA f l uid c oul d p otential l y c ause p artic ul ate f oul ing of th e h eat ex c h anger tub es if th e f l uid vel oc ity is l ess th an th e term inal settl ing vel oc ity of th e deb ris. How ever, f oul ing is c onsidered a l ong-term p h enom enon. In addition, th e h eat l oad of th e CS h eat ex c h angers is greatest at th e start of th e event and dec reases rap idl y over th e f irst 24 h ours. Heat rem oval c ap ac ity is not degraded over th is sh ort p eriod. Any p otential reduc tion in c ap ab il ity over th e 30 day m ission tim e is gradual and w el l w ith in th e nom inal h eat ex c h anger design.

T h e CS h eat ex c h angers' and CS m inif l ow h eat ex c h angers' tub es are sp ec if ied to b e c onstruc ted of 304 stainl ess steel . Stainl ess steel is ap p rop riate f or use as h eat ex c h anger tub ing and is standard f or use in m il dl y ab rasive ap p l ic ations. T h e tub e m aterial w il l not signif ic antl y degrade c onsidering op eration w ith p ost-L OCA f l uid over an intended m ission tim e of 30 day s.

T h eref ore, th e CS h eat ex c h angers and CS m inif l ow h eat ex c h angers are f ul l y c ap ab l e of p erf orm ing th eir intended f unc tion using p ost-L OCA f l uid as th e p roc ess f l uid.

T h e tub e w ear f or th e CS h eat ex c h angers and CS p um p m inif l ow h eat ex c h angers is eval uated assum ing a f ree-f l ow ing w ear m odel , th e m ission tim e of 30 day s, and c onservative m ass c onc entration of deb ris of 1,000 p p m , w h ic h is l arger th an th at in T ab l e 4.2-5. T h e tub e w ear f or th e CS h eat ex c h angers and CS p um p m inif l ow h eat ex c h angers is c om m onl y c al c ul ated to 0.064 m m ( 0.00252 inc h ) . T h e avail ab l e th ic k nesses f or erosion, i.e. th e ac tual w al l th ic k ness m inus th e req uired w al l th ic k ness to retain p ressure, are c al c ul ated to 0.381 m m ( 0.015 inc h ) f or CS h eat ex c h anger and 0.635 m m ( 0.025 inc h ) f or CS p um p m inif l ow ex c h anger. T h e total tub e w ear during th e m ission tim e ( 30 day s) is very sm al l c om p aring th e avail ab l e th ic k ness f or erosion. T h eref ore, th e h eat ex c h anger tub es h ave suf f ic ient th ic k ness to w ith stand th e erosion ef f ec ts of th e deb ris p artic l es.

4.2.3.3 Evaluation of V alves, Orif ices and Pipes 4.2.3.3.1 Block age and Deb ris Settling Evaluation f or V alves, Orif ices and Pipes T h e strainer h ol e siz e is 2.38 m m ( 0.094 inc h ) . T h eref ore, w h en th e gap of th e c om p onents is 2.38 m m

( 0.094 inc h ) + 0.238 m m ( 0.0094 inc h ) ( 10% ) or 2.62 m m ( 0.103 inc h ) or l ess th an th is val ue, th e f l ow -p ath or c om p onent m ay b e b l oc k ed. T h is is c onsistent w ith Ref erenc e [ 4-3] . Com p onents th at are in th e f l ow -

p ath s during ac c idents are l isted in T ab l e 4.2-1.

Piping Fl uid vel oc ity dec reases w ith an inc rease in p ip e diam eter. T h eref ore, th e l ow est vel oc ity in th e ECCS oc c urs in th e region w ith th e l argest p ip e diam eter/ f l ow area. Fl ow vel oc ities in al l p ip ing ex c ep t several c ases ( 24 inc h , 20 inc h , and 10 inc h SI Pum p suc tion l ines and 12 inc h SI p um p disc h arge l ine) are ab ove KEPCO & KHNP 65

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 th e settl ing vel oc ities of th e p ost-L OCA f l uid. Ref er to T ab l e 4.2-6.

Som e c onservative assum p tions are c onsidered to f ac il itate th e c om p arison and are disc ussed b el ow .

First, th e p um p sh utof f f l ow rates at w h ic h p um p c avitation is l ik el y to oc c ur, rath er th an th e design f l ow rates, are used to c al c ul ate th e f l ow vel oc ities. T h is l ow ers th e f l ow vel oc ities f or additional c onservatism f or th e deb ris settl ing eval uation. T h ese c al c ul ated vel oc ities are c om p ared to th e settl ing vel oc ities of 0.046 m / s ( 0.15 f t/ s) and 0.002 m / s ( 0.008 f t/ s) f or c oating and l atent f ib er, resp ec tivel y , as rep orted in T ab l e 4-2 of NEI 04-07. Sinc e th e assum ed f l ow vel oc ities are c onsiderab l y h igh er th an th e settl ing vel oc ities, th e deb ris is not l ik el y to settl e in th e SI and CS sy stem s. For l atent p artic l e deb ris, th ere is no inf orm ation in NEI 04-07, so term inal settl ing vel oc ity is c onservativel y c al c ul ated using Stok es L aw .

Al l p artic l e siz es used f or term inal settl ing vel oc ity of th e l atent p artic l e deb ris are assum ed to b e th e strainer h ol e siz e of 0.094 inc h , w h ic h is c onsiderab l y l arge c om p ared to T ab l e V -2 of SE f or NEI 04-07.

T h is m ax im iz es th e term inal settl ing vel oc ity . T h e m ax im um term inal settl ing vel oc ity is c onsiderab l y h igh er th an th e term inal settl ing vel oc ities f or oth er deb ris l isted in T ab l e 4-2 of NEI 04-07. Suf f ic ient c onservatism is th us p rovided f or th e deb ris settl ing eval uation.

B ec ause deb ris settl ing is a l onger term p h enom enon, th ere is no sh ort term im p ac t on th e f l ow vel oc ities over th e tim e p eriod of interest. T h is f ac t, c om b ined w ith th e c onservatism in th e f l ow vel oc ities and th e l atent p artic l e deb ris term inal settl ing vel oc ity m ak e th e p rob ab il ity of b l oc k ages in p ip ing ex trem el y l ow .

B ased on th e ab ove c onsiderations, deb ris settl ing w il l not oc c ur or af f ec t sy stem op eration in p ip ing and any assoc iated val ves w h ere th e f l ow vel oc ity f or l atent deb ris is l ess th an th e term inal settl ing vel oc ity .

T h e p ip ing and assoc iated val ves w ith l ow er assum ed f l ow vel oc ity th an th e deb ris settl ing vel oc ity are l isted in T ab l e 4.2-9. In th e l isted p ip ing and assoc iated val ves, th e f l uid f l ow vel oc ities are c al c ul ated b ased on th e ex p ec ted p um p op eration. T h e resul ts sh ow th at th e deb ris w il l not settl e b ec ause th e c al c ul ated f l uid f l ow vel oc ities are m uc h h igh er th an th e term inal settl ing vel oc ity of 0.7 f t/ sec under th e ex p ec ted p um p op erating c onditions. T h eref ore, th ere w il l b e no im p ac t of th e l atent deb ris on th e sy stem op eration under ex p ec ted p um p op erating c onditions.

V alves T h e val ve ty p es th at are used in th e f l ow -p ath during an ac c ident are gate, c h ec k , gl ob e and b utterf l y val ves, see T ab l e 4.2-1.

1) Gate val ves Gate val ves are used f ul l -op en or f ul l -c l ose. T h e gate val ve siz es are ab ove 101.6 m m ( 4 inc h )

( see T ab l e 4.2-1) . Fl ow vel oc ities in al l c ases ex c ep t f or gate val ves on 20 inc h and 10 inc h SI p um p suc tion l ines and 18 inc h CS p um p suc tion l ines are ab ove th e settl ing vel oc ities of th e p ost-L OCA f l uid ( ref er to T ab l e 4.2-6) . NU REG/ CR-6902 ( Ref erenc e [ 4-4] ) states th at val ve op enings signif ic antl y l arger th an th e deb ris siz e w il l not c l og. T h e strainer h ol e siz e is 2.38 m m ( 0.094 inc h ) .

T h e 101.6 m m ( 4 inc h ) val ve op ening is c onsiderab l y l arger th an any ex p ec ted p artic l e p assing th rough th e sum p strainer. T h eref ore, th e val ves do not c l og due to p ost-L OCA insul ation deb ris.

2) Ch ec k val ves Ch ec k val ves are used w ith suf f ic ient f l ow rate, and c h ec k val ve siz es are ab ove 101.6 m m ( 4 inc h )

( see T ab l e 4.2-6) . Fl ow vel oc ities in al l c ases ex c ep t f or c h ec k val ves on 12 inc h SI p um p suc tion l ines and 18 inc h CS p um p suc tion l ines are ab ove th e settl ing vel oc ities of th e p ost-L OCA f l uid ( ref er to T ab l e 4.2-6) . Ref erenc e [ 4-4] states th at val ve op enings signif ic antl y l arger th an th e KEPCO & KHNP 66

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 deb ris siz e w il l not b e c l ogged. T h e strainer h ol e siz e is 2.38 m m ( 0.094 inc h ) . T h e 101.6 m m

( 4 inc h ) val ve op ening is c onsiderab l y l arger th an any ex p ec ted p artic l e p assing th rough th e sum p strainer. T h eref ore, th e val ves do not c l og due to p ost-L OCA insul ation deb ris.

3) Gl ob e val ves ECCS and CSS f l ow is c ontrol l ed th ough a c om b ination of orif ic es and th rottl ed val ves. Gl ob e val ves norm al l y are f ul l op en b ut m ay b e used f or th rottl ing sy stem f l ow . ECCS and CSS p ressure and f l ow are m onitored in th e M CR. In general , if a gl ob e val ve is in a th rottl ed p osition and it b egins to c l og, sy stem f l ow w il l dec rease. Op erator ac tion m ay b e tak en to op en th e val ve, th us c l earing th e p otential c l og. In th e APR1400, gl ob e val ve siz es are ab ove 101.6 m m ( 4 inc h ) ( see T ab l e 4.2-1) . Fl ow vel oc ities in al l c ases are ab ove th e settl ing vel oc ities of th e p ost-L OCA f l uid

( ref er to T ab l e 4.2-6) . Ref erenc e [ 4-4] states th at val ve op enings signif ic antl y l arger th an th e deb ris siz e w il l not b e c l ogged. T h e strainer h ol e siz e is 2.38 m m ( 0.094 inc h ) . T h rottl e val ves are ex p ec ted to b e th rottl ed to a m inim um of 50.8 m m ( 2 inc h ) op en b etw een th e val ve disc and seat. T h e 50.8 m m ( 2 inc h ) val ve op ening is c onsiderab l y l arger th an any ex p ec ted p artic l e p assing th rough th e sum p strainer. T h eref ore th e val ves do not c l og due to p ost-L OCA insul ation deb ris.

Orif ice ECCS and CSS f l ow is c ontrol l ed th ough a c om b ination of orif ic es and th rottl ed val ves. Orif ic es are used f or th rottl ing sy stem f l ow . ECCS and CSS p ressure and f l ow are m onitored in th e M CR.

T h e orif ic e siz es are ab ove 20.3 m m ( 0.8 inc h ) . Fl ow vel oc ities in al l c ases are ab ove th e settl ing vel oc ities of th e p ost-L OCA f l uid ( T ab l e 4.2-6) . T h eref ore, th e p otential of orif ic e p l ugging is very l ow .

Spray Noz z les T h e c ontainm ent m ain sp ray noz z l es and aux il iary sp ray noz z l es h as an orif ic e of 13.1 m m ( 0.516 inc h ) and 5.6 m m ( 0.22 inc h ) diam eter, resp ec tivel y . T h is orif ic e is th e sm al l est p ortion of sp ray noz z l e. T h e strainer h ol e siz e is 2.38 m m ( 0.094 inc h ) . Containm ent sp ray noz z l es are signif ic antl y l arger th an th e strainer h ol e siz e. T h eir one-p iec e design p rovides a l arge, unob struc ted f l ow p assage th at resists c l ogging b y p artic l es. T h eref ore, th e p otential of sp ray noz z l e p l ugging is very l ow .

4.2.3.3.2 Wear Rate Evaluation f or V alves, Orif ices, Spray Noz z le, and Pipes Erosive w ear is c aused b y p artic l es th at im p inge on a c om p onent surf ac e and rem ove m aterial f rom th e surf ac e b ec ause of m om entum ef f ec ts. T h e w ear rate of a m aterial dep ends on th e deb ris ty p e, deb ris c onc entration, m aterial h ardness, f l ow vel oc ity , and val ve p osition.

Fl ow rates of 6,057 L / m in ( 1,600 gp m ) and 27,255 L / m in ( 7,200 gp m ) ) f or SIS and CSS, resp ec tivel y , are c onservativel y assum ed f or th e w ear rate eval uation of th e c om p onents l isted in T ab l e 4.2-1. T h e ECCS and CSS design f l ow rates l isted in T ab l e 4.2-1 inc l ude th e m ax im um f l ow rate of th e SI p um p , CS p um p ,

and th e sum of th e SIS and CSS f l ow s b ased on sy stem c onf iguration.

T ab l e 4.2-7 c ontains a sum m ary of th e p ip ing, sp ray noz z l es, and orif ic e w ear c al c ul ation. T h e resul ts sh ow th at th e sy stem p ip ing and c om p onent f l ow resistanc es w il l b e c h anged m inim al l y during th e c ourse of th e L OCA. T h e ex p anded noz z l e orif ic e siz e due to w ear reduc es th e noz z l e orif ic e p ressure drop sl igh tl y , w h ic h al l ow s entrained gas to b e retained in th e sp ray ed w ater. T h is ef f ec t c reates a m ore even f l ow of sp ray ed w ater th rough th e noz z l e orif ic e..

KEPCO & KHNP 67

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T h e ECCS and CSS val ves w il l b e q ual if ied to op erate w ith th e p ost-L OCA f l uids f or at l east 30 day s in ac c ordanc e w ith ASM E Q M E-1-2007 as endorsed b y RG 1.100 Revision 3. As a p art of th e q ual if ic ation, th e w ear eval uation f or th e ECCS and CSS val ves in th e f l ow p ath during an ac c ident, suc h as gate, c h ec k , gl ob e and b utterf l y val ves, is p erf orm ed. T h e val ves are not req uired to b e th rottl ed in th e sy stem op eration b ec ause th e sy stem s are f l ow b al anc ed b y th e f l ow orif ic es. An inc rease in f l ow area due to erosive w ear ap p l ies to m anual l y th rottl ed val ves onl y , in ac c ordanc e w ith th e guidanc e p rovided in NRC Inf orm ation Notic e 97-76. In addition, b ec ause th e val ve w al l is al w ay s general l y th ic k er th an th e p ip e w al l th ic k ness, and if th e th ic k ness of assoc iated p ip es are ac c ep tab l e, th e val ves are al so ac c ep tab l e.

T h eref ore, th ere is no ex p ec ted im p ac t due to erosive w ear on th e ECCS and CSS val ves. T h ese val ves th eref ore c om p l y w ith th e guidanc e of RG 1.82 Revision 4.

4.2.3.4 Instrument T ub ing Clogging Evaluation Ac c ording to W CAP-16406-P ( Ref erenc e [ 4-3] ) , w h en th e instrum ent tub ing l ines m aintain a sol id state p rior to em ergenc y c ore c ool ing op eration, it is determ ined tub ing integrity is not af f ec ted b ec ause th ere is al m ost no p ossib il ity of deb ris ingestion, and th e eval uation sh ow s th ere are no ef f ec ts f rom f l ow b l oc k age and w ear b ec ause f l ow vel oc ities in al l c ases are ab ove th e settl ing vel oc ities of th e p ost-L OCA f l uid.

Al so, al l instrum ent c onnec tions are at th e side or at th e top of th e p ip e and th e SIS and CSS do not c ontain any b ottom -m ounted instrum ent c onnec tions.

4.2.3.5 Chemical Ef f ects Evaluation Ch em ic al p rec ip itates ( al um inum ox y -h y drox ide, sodium al um inum sil ic ate and c al c ium p h osp h ate) are f orm ed w h en c onc rete and L OCA-generated deb ris m aterial s are ex p osed to th e b uf f ering m aterial s in th e IRW ST . T h is reac tion f orm s additional sol id sp ec ies th at c oul d p otential l y p ass th rough th e sum p sc reen and degrade th e p erf orm anc e of th e ECCS and CSS.

In-vessel f uel b l oc k age tests p erf orm ed using p artic ul ate, f ib er and al um inum ox y -h y drox ide p rec ip itate dem onstrate th at th e f l ow resistanc e c reated b y th e c h em ic al p rec ip itate is signif ic antl y l ess th an th e p um p h ead th at is avail ab l e in th e ECCS and CSS p ip ing sy stem . Sec ondl y , sim il ar to th e p artic ul ate and f ib er deb ris m aterial s, onl y c h em ic al p rec ip itates sm al l er th an ( or eq ual to) th e p erf orated p l ate h ol e siz e of IRW ST sum p strainer w il l b e ingested b y th e ECCS and CSS. T h e diam eter of th e ECCS and CSS p ip ing, orif ic es, sp ray noz z l es, val ves and h eat ex c h anger tub es are signif ic antl y l arger th an th e siz e of th e ingested c h em ic al p rec ip itates, and th e vel oc ity of th e p ost-L OCA f l uid is ex p ec ted to b e suf f ic ient to avoid settl ing. T h eref ore, c om p onents dow nstream of th e sum p strainers are not ex p ec ted to b ec om e c l ogged w ith c h em ic al p rec ip itates suc h th at b l oc k age of f l ow oc c urs.

In addition, th e q ual if ic ation of th e ECCS and CSS p um p s, p erf orm ed w ith c onservative am ounts of p ost-L OCA deb ris ( T ab l e 4.2-5) , in ac c ordanc e w ith ASM E Q M E-1-2007, w il l inc l ude c onf irm ation th at th e internal running c l earanc e of th e ECCS and CSS p um p s is suf f ic ientl y l arge enough to avoid c l ogging, and sup p orts ac c ep tab l e p um p and seal op eration during th e 30-day p ost-L OCA m ission tim e.

T h e c h em ic al p rec ip itates are al so unl ik el y to reduc e th e ef f ic ienc y of th e h eat ex c h anger b ec ause m ost p rec ip itates w il l f orm l ater in th e p ost-L OCA event w h en tem p eratures h ave dec reased ( ( NU REG/ CR-6913

( Ref erenc e [ 4-5] ) and NU REG/ CR-6914 ( Ref erenc e [ 4-6] ) ) and w h en th e req uired h eat transf er c ap ac ity of th e CSS h eat ex c h angers h as am p l e m argin. Prec ip itates th at f orm soon af ter th e p ip e b reak are onl y ex p ec ted to f orm , at m ost, th in dep osit f il m s on th e h eat ex c h anger tub es. Dep osit th ic k nesses are l im ited b y sc rub b ing f rom p artic ul ate in th e c ool ant as w el l as th e rel ativel y h igh f l ow rate and p ressure dif f erential . In addition, th e CS h eat ex c h angers are designed and sp ec if ied w ith c onservative f oul ing KEPCO & KHNP 68

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 f ac tors to m ax im iz e h eat transf er ef f ic ienc y and p erf orm anc e. Op erating ex p erienc e h as al so dem onstrated th at f oul ing is a l ong-term p h enom enon and h eat ex c h angers c an stil l p erf orm adeq uatel y w ith signif ic ant f oul ing. T h eref ore, th e c h em ic al p rec ip itates are not ex p ec ted to signif ic antl y im p air th e h eat transf er c ap ab il ity of th e CS h eat ex c h angers.

4.2.4 Overall System Evaluation T h e f l ow inc rease l ess th an 3% f or an individual c om p onent due to erosive w ear is c onsidered as insignif ic ant b ec ause th e 3% val ue is w el l w ith in nom inal c om p onents m anuf ac turing tol eranc es and w el l w ith in th e standard f l uid f l ow c al c ul ation tol eranc es. Furth erm ore, if th e f l ow inc rease f or individual c om p onent is l ess th an 3 % , th e total sy stem f l ow inc rease w il l b ec om e l ess th an 3% and w il l b e al so c onsidered as insignif ic ant to th e sy stem f l ow c al c ul ations and design b asis anal y sis.

T h e tub e w ear f or th e CS h eat ex c h angers and CS p um p m inif l ow h eat ex c h angers is c om m onl y c al c ul ated to 0.064 m m ( 0.00252 inc h ) . T h e inc rease of tub e f l ow area due to tub e w ear w il l resul t in th e f l ow inc rease of 0.9% f or th e CS h eat ex c h angers and 1.3% f or th e CS p um p m inif l ow h eat ex c h angers.

T h e f l ow inc rease in th e p ip ing, orif ic es, and sp ray noz z l es are l isted in th e T ab l e 4.2-7. T h e m ax im um f l ow inc rease of th e c om p onents in th e f l ow p ath of ECCS and CSS does not ex c eed 3% ex c ep t f or SI-OR08A/ B / C/ D orif ic es. T h ese orif ic es are instal l ed w ith th e oth er orif ic es ( SIOR01A/ B / C/ D) in series on th e SI p um p m inif l ow p ath f or th e f l ow b al anc e. A suf f ic ient p ressure drop w il l b e stil l devel op ed in th e m inif l ow p ath th rough th e oth er orif ic e w ith m uc h l ess erosive w ear; i.e., th e f l ow b al anc e to th e m inif l ow p ath is stil l assured. In real ity , th e ac tual f l ow inc rease due to erosive w ear th rough th e orif ic es w il l b e m uc h l ess sinc e th e design f l ow to th e m inif l ow p ath is 50% l ess th an th e assum ed f l ow rate. T h eref ore, f l ow inc rease in th e p ip ing, orif ic es, and sp ray noz z l es does not af f ec t th e overal l inj ec tion f l ow p ath to th e RCS and th e overal l sp ray f l ow p ath to th e c ontainm ent. In addition, th e sy stem f l ow rate and disc h arge p ressure f or th e ECCS and CSS are c ontinuousl y m onitored in th e M CR. Al th ough val ves in th e f l ow p ath do not need to b e adj usted during an ac c ident, if nec essary , saf ety inj ec tion and h ot l eg inj ec tion isol ation val ves m ay b e th rottl ed to satisf y th e desired f l ow rate.

B ased up on th e resul ts of w ear eval uation f or eac h c om p onent of ECCS and CSS, th e f l ow inc rease due to w ear does not ex c eed 3% in al l f l ow p ath s of ECCS and CSS. T h eref ore, f l ow b al anc es and sy stem p erf orm anc e are not af f ec ted in an ap p rec iab l e m anner. T h e antic ip ated dow nstream ef f ec ts on resul ting f l ow s and p ressures are c onsistent or c onservative w ith resp ec t to th e inp uts used ac c ident anal y sis. T h e m inor resistanc e c h anges do not af f ec t th e sy stem f l ow c al c ul ations and design b asis anal y sis.

4.2.5 Evaluation Summary T h e intent of th is sec tion is to assess th e dow nstream ef f ec ts of ECCS and CSS of th e APR1400 under p ost-L OCA c onditions f ol l ow ing new req uirem ent.

T h e resul t of assessm ent is th at ECCS and CSS of th e APR1400 are f ul l y designed to p erf orm th eir saf ety f unc tion under p ost-L OCA c onditions. T h is resul t al so verif ies th at inadeq uate c ore or c ontainm ent c ool ing does not oc c ur b ec ause of deb ris b l oc k age at f l ow restric tions, p l ugging or ex c essive w ear of c l ose-tol eranc e c om p onent ( e.g., p um p s, h eat ex c h angers, p ip ing, val ves, sp ray noz z l es) in th e f l ow p ath .

KEPCO & KHNP 69

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 4.3 In-V essel Dow nstream Ef f ects T h e ob j ec tive of in-vessel dow nstream -ef f ec ts eval uation is to dem onstrate th at th ere is reasonab l e assuranc e th at suf f ic ient l ong-term c ore-c ool ing ( L T CC) is ac h ieved to satisf y th e req uirem ents of 10 CFR 50.46, w ith deb ris and c h em ic al p roduc ts th at are p ostul ated to b e transp orted to th e reac tor vessel .

T h is eval uation f or th e APR1400 is p erf orm ed ap p l y ing th e eval uation m eth ods and ac c ep tanc e b ases p rovided in th e W CAP-16793-NP Revision 2 ( Ref erenc e [ 4-7] ) and th e NRC saf ety eval uation ( SE) f or th e W CAP-16793-NP Revision 2 ( Ref erenc e [ 4-8] ) .

4.3.1 ECCS Flow Rates Fol l ow ing a L OCA, th e ECCS w il l del iver f l uid and deb ris to th e RCS. T h e am ount of deb ris th at reac h es th e reac tor c ore is dep endent on th e ECCS inj ec tion c onf iguration and b reak l oc ation. For th e APR1400, ECC f l ow is del ivered to th e direc t vessel inj ec tion ( DV I) l ines or h ot-l egs. T h e ECC f l ow rates to th e b reak l oc ations identif ied in L OCA sc enarios are as f ol l ow s.

4.3.1.1 H ot-leg Break Condition In th e event of a h ot-l eg b reak , th e c ool ant p um p ed into th e DV I l ines is f orc ed into th e reac tor vessel ,

dow n th e dow nc om er and up th rough th e reac tor c ore tow ard th e b reak . During th e L T CC p eriod, c ore f l ow , p l us a sm al l am ount of c ore-b y p ass f l ow , is eq ual to th e total ECC f l ow del ivered to th e dow nc om er.

Af ter a h ot-l eg b reak event, th e m ax im um rec irc ul ation f l ow rate is 18,699 L / m in ( 4,940 gp m ) , and th e num b er of f uel assem b l ies ( FA) is 241. Sinc e th e c ore b y p ass f l ow is not c redited, al l th e ECC w ater p asses th rough th e reac tor c ore to ex it th e b reak . T h eref ore, th e f l ow rate p er FA is c al c ul ated to divide 18,699 L / m in ( 4,940 gp m ) b y 241, and its val ue is 78 L / m in ( 20.5 gp m ) . T h e h ot-l eg b reak c ondition at th e m ax im um f l ow rate is c h osen to ob tain m ax im um p ressure drop at th e test c ol um n.

4.3.1.2 Cold-leg Break Condition In th e event of a c ol d-l eg b reak , ECC w ater inj ec ted into th e f ail ed l oop w il l ex it th e b reak and w ater inj ec ted into th e intac t l oop w il l enter th e dow nc om er annul us, ensuring th at th e dow nc om er is f il l ed, at m inim um , to th e b ottom of th e c ol d-l eg noz z l e. T h e c ore f l ow is onl y w h at is req uired to m ak e up f or c ore b oil ing to rem ove th e dec ay h eat. T h e ECC w ater k eep s th e dow nc om er f ul l to at l east th e b ottom of th e c ol d-l eg noz z l es, and any ex c ess w ater f l ow s out of th e c ol d-l eg b reak l oc ation and b ac k into th e IRW ST .

In th is c ase, m ost of th e ECC w ater sp il l s direc tl y out of th e b reak l oc ation. T h e am ount of deb ris th at reac h es th e reac tor vessel l ow er p l enum and c ore inl et af ter a c ol d-l eg b reak sh oul d b e signif ic antl y l ess th an th at f rom a h ot-l eg b reak . T h e ECC f l ow rate p er FA is 14 L / m in ( 3.65 gp m ) at rec irc ul ation start tim e ( around 700 sec onds af ter L OCA) as f ol l ow s.

4.3.1.2.1 Recirculation Start T ime T h e APR1400 h as no sum p sw itc h -over op eration as th e ECCS p um p suc tion is al igned to th e IRW ST during th e L T CC p eriod. T o p rovide th e req uired tim e f or deb ris to reac h th e reac tor vessel af ter a L OCA, a c onservative val ue of rec irc ul ation start tim e is c al c ul ated as f ol l ow s.

KEPCO & KHNP 70

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS T h e tim e req uired f or deb ris to reac h th e reac tor vessel is ap p rox im atel y 1,400 sec onds. Hal f of th is tim e is used f or c onsidering unk now ns ( l ik e m ix ing) and th e rec irc ul ation start tim e is set at 700 seconds f or dow nstream ef f ec t eval uation. T h is tim e is used to determ ine th e c ore b oil -of f rate f ol l ow ing a c ol d-l eg b reak w ith DV I, as f ol l ow s.

4.3.1.2.2 Core Boil-of f Rate T h e c ore b oil -of f rate at th e tim e of rec irc ul ation start ( 700 sec onds) is sel ec ted as th e m ax im um ECC f l ow rate to th e reac tor vessel af ter a c ol d-l eg b reak . Detail s of th e c al c ul ation m eth od are desc rib ed in Sec tion 3.5.3 of th e Ref erenc e [ 4-9] .

Core b oil -of f rate ( w ) = ( c ore dec ay h eat) / ( c ore enth al p y rise) = Q DH/ H Core Dec ay Heat ( Q DH)

T h e c ore dec ay h eat is c al c ul ated as a f unc tion of tim e:

Q DH = ( P/ Po) ( Po)

TS Core Enth al p y Rise ( H)

KEPCO & KHNP 71

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T h e enth al p y rise in th e c ore is a f unc tion of c ore inl et sub c ool ing and th e saturation p ressure at th e c ore ex it. T h e enth al p y rise in th is c al c ul ation is th e l atent h eat of vap oriz ation.

T h eref ore, H= h fg W h ere h f g is determ ined using th e c ore ex it p ressure, w h ic h is b ased on th e c ontainm ent p ressure p l us an inc rease f or f l ow l osses th rough th e l oop s.

Pc ore_ ex it = Pc ont + dPl oop s W h ere, Pc ont = c ontainm ent p ressure at th e L OCA c ondition dPl oop = p ressure drop s th rough th e l oop s TS T h eref ore, th e f l ow rate p er FA is c al c ul ated b y dividing 3,322 L / m in ( 877.6 gp m ) b y 241, and its val ue is 14 L / m im ( 3.64 gp m ) .

4.3.1.3 Cold-leg Break af ter H LSO Condition T h ree h ours af ter a c ol d-l eg b reak , th e op erator starts sim ul taneous h ot-l eg/ DV I l ine inj ec tion ( h ot-l eg sw itc h over: HL SO) . T w o SI p um p s are f or h ot-l egs, and tw o SI p um p s are f or DV I l ines. Sinc e th e w ater inj ec ted into DV I l ines sp il l s direc tl y out of th e b reak l oc ation, th e w ater inj ec ted into h ot-l egs goes dow n th rough th e reac tor c ore tow ard th e b reak . T ab l e 4.3-1 sum m ariz es th e ECCS f l ow rates p er FA, f ol l ow ing a L OCA.

4.3.2 Amount of Bypass Deb ris per Fuel Assemb ly T o eval uate th e dow nstream c om p onents, a determ ination of th e q uantity and c h arac teristic s of th e b y p ass deb ris is nec essary . Given th at th e strainer is f ab ric ated f rom p erf orated p l ate, th e strainer sh oul d b e siz ed l arge enough to p roduc e an ac c ep tab l e p ressure drop f or th e deb ris l oad, b ut not ex c essivel y l arge th at it p asses too m uc h b y p ass deb ris. T h e q uantity of b y p ass deb ris is a f unc tion of h ol e siz e and strainer surf ac e area. W h il e th e am ount of b y p ass deb ris is al so a f unc tion of th e vel oc ity of th e f l uid p assing and c arry ing th e deb ris th rough th e strainer h ol es, th is is im p l ic it in th e surf ac e area of th e strainer and th e design f l ow rate.

T h e k ey c om p onent in th e b l oc k age of dow nstream c om p onents is th e p resenc e of f ib rous deb ris m aterial s. Partic ul ates and c h em ic al ef f ec ts c an b ec om e entrained in th e rec irc ul ation f l ow p ath , b ut w ith out f ib rous m aterial s, a deb ris b ed and b l oc k age p oint c annot f orm .

T h e APR1400 is a l ow f ib er p l ant, and th ere is no f ib rous insul ation inside th e z one of inf l uenc e ( Z OI) .

Onl y l atent deb ris is assum ed, and its design val ue is l im ited to 90.72 k g ( 200 l b m ) w ith 83.91 k g ( 185 l b m )

of p artic ul ate and 6.8 k g ( 15 l b m ) of f ib er. Al l th e deb ris ( ex c ep t f ib er) th at is transp orted to th e IRW ST is assum ed to b y p ass th e strainer.

KEPCO & KHNP 72

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Partic ul ate Deb ris Ep ox y c oatings are c onsidered to b e destroy ed w ith in th e Z OI. B ased on th e up stream anal y sis, th e 3 3 q uantity of destroy ed c oatings is 0.0878 m ( 3.1 f t ) . NEI-04-07 ( Ref erenc e [ 3-2] ) estim ates th e p artic l e 3 3 m 1.51 g/ c m ( 94 l b m / f t ) . A suitab l e and c om m on surrogate used in th e tests in th e U nited States, is sil ic on c arb ide ( SiC) . It h as a m ean p artic l e

-4 m ( 3.94x 10 inc h ) and m aterial sp ec if ic gravity of 3.2, w h ic h c orresp onds to a density of 3.20 3 3 g/ c m ( 199.5 l b m / f t ) . T h e SiC is sel ec ted f or resistanc e to dissol ution in th e tab w ater and interac tion

-4 w ith oth er m aterial s. m m ( 3.94x 10 inc h ) sp h eres, th e SiC surrogate c ontains a range of p artic l es siz es. U se of th is m aterial is ac tual l y q uite c onservative sinc e it w il l c reate a h igh er p ac k ing density and c reate m ore drag and h ead l oss in th e deb ris b ed. T h e siz e distrib ution of th e SiC used in test is avail ab l e in th e test rep ort ( Ref erenc e [ 4-10] ) . Determ ining th e am ount of SiC added to th e test is im p ortant b ec ause th e vol um e of p artic ul ates is p reserved. T h eref ore, th e m ax im um am ount of SiC to b e added is c al c ul ated as f ol l ow s:

lbm M p = 3 . 1 ft 3 x 1 9 9 . 5 / 2 4 1 = 2 . 5 7 lbm ( 1,164 g) ft 3 Sim il arl y , th e m ass of l atent p artic ul ate to b e added is c al c ul ated as f ol l ow s:

1 8 5 lbs M lp = = 0 . 7 6 7 lbs ( 348 g) 2 4 1 Fib rous Deb ris T h e l atent f ib er is rep resented b y NU KON l ow density f ib ergl ass ( rec om m ended b y NEI-04-07) w ith an as-3 3 f ab ric ated density of 0.038 g/ c m ( 2.4 l b m / f t ) ( see NEI-04-07 SER Ap p endix V II) . T h e sourc e of th e NU KON used in tests is avail ab l e in ( Ref erenc e [ 4-10] ) . T otal strainer b y p ass f ib er f or th e APR1400 w ith 6.80 k g ( 15 l b m ) of l atent f ib er is 1.67 k g ( 3.68 l b m ) ( Sec tion 4.1) . T h e m ass of f ib er to b e added to th e test is:

3 . 6 8 lbm M f = = 0 . 0 1 5 lbm ( 6.93 g) 2 4 1 Ch em ic al Prec ip itates B ased on th e design c onditions ( T ab l e 3.8-4) , th e f ol l ow ing c h em ic al p rec ip itates are avail ab l e in th e IRW ST f l uid.

Cal c ium Ph osp h ate  : 0.71 k g ( 1.56 l b m )

Sodium Al um inum Sil ic ate  : 4.36 k g ( 9.6 l b m )

Al um inum Ox y -h y drox ide  : 153.6 k g ( 338.7 l b m )

Given th e rel ative p rop ortions, sinc e al um inum ox y -h y drox ide c an b e c onservativel y used to rep resent th e oth er p rec ip itates ( Ref erenc e [ 3-11] ) ; onl y Al OOH is used in th e test. T h e total c h em ic al p rec ip itate m ass of 158.67 k g ( 349.8 l b m ) is rep resented b y Al OOH. T h is p rec ip itate susp ension h as a c al c ul ated c onc entration of 11g/ L . T h e vol um e of p rep ared Al OOH surrogate f or th e test is c al c ul ated as f ol l ow s:

liter 1gal V Al OOH = 158.67kg / 241x x = 15.8gal ( 59.8 l iters) 0.011kg 3.785liter T h e b y p ass deb ris ty p es and am ounts p er FA are sum m ariz ed in T ab l e 4.3-2.

KEPCO & KHNP 73

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 4.3.2.1 Fib er Loads at H ot-leg Break Condition In th e event of a h ot-l eg b reak , al l th e c ool ant p um p ed into th e DV I l ines is f orc ed into th e reac tor vessel ,

dow n th e dow nc om er and up th rough th e reac tor c ore tow ard th e b reak . Sinc e th e al ternate f l ow p ath s in th e reac tor vessel are not c redited f or dem onstrating adeq uate L T CC in th e APR1400 design eval uation, th e f ib er l oads p er FA is eq ual to th e c al c ul ated val ue 6.93 g ( 0.015 l b m ) under th e h ot-l eg b reak c ondition.

4.3.2.2 Fib er Loads at Cold-leg Break Condition In th e event of a c ol d-l eg b reak , onl y a p art of ECC w ater is inj ec ted into th e c ore. T h e c ore f l ow rate is l im ited b y th e c ore b oil -of f rate ( al ready desc rib ed in Sec tion 4.3.1.2.2) . T h e c urrent sec tion desc rib es th e total am ount of f ib er l oads f ol l ow ing a c ol d-l eg b reak .

Assum p tions

1) Al l deb ris is generated during th e f irst 700 sec onds ( 11.7 m inutes) af ter th e c ol d-l eg b reak .

2) Al l deb ris is c om p l etel y m ix ed into th e IRW ST at 700 sec onds.

3) Deb ris is not trap p ed at any l oc ation al ong th e f l ow p ath s.

Eq uations T h e total am ount of deb ris transp orted to th e c ore ( M CORE) is c al c ul ated as f ol l ow s:

M BO M CORE = M tot M Water w h ere, M tot  : total am ount of b y p ass deb ris ( f ib er : 1.67 k g ( 3.68 l b m ) )

3 M W ater  : m inim um am ount of IRSW T w ater ( 993.2 m ( 262,388 gal ) )

M B O : total am ount of b oil -of f w ater t m ax M BO = 1 1 .7 WBO ( t ) dt W h ere, W B O  : b oil -of f rate tm ax  : start tim e of HL SO op eration ( 2 h ours) + 2 h our f or c onservatism = 4 h ours ( 240 m inutes)

T h e tim e dep endent b oil -of f rate at 240 m inutes is c al c ul ated b y th e m eth ods desc rib ed in Sec tion 4.3.1.2.2, and th e val ue is 1,491 L / m in ( 393.9 gp m ) as sh ow n in Figure 4.3-1.

Cal c ul ation KEPCO & KHNP 74

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS 4.3.3 Availab le Driving H ead It m ust b e dem onstrated th at th e avail ab l e h ead to drive th e ECC f l ow into th e c ore is greater th an th e h ead l oss ac ross th e c ore due to p ossib l e deb ris b uil dup . T h e f ol l ow ing rel ationsh ip m ust b e true to ensure th at a suf f ic ient f l ow is avail ab l e to m aintain th e L T CC:

dPavail > dPdeb ris T h e c ore f l ow is onl y p ossib l e if th e m anom etric b al anc e b etw een th e dow nc om er ( DC) and th e c ore is suf f ic ient to overc om e th e f l ow l osses in th e reac tor vessel ( RV ) dow nc om er, RV l ow er p l enum , c ore, and l oop s, at th e ap p rop riate f l ow rate.

dPavail = dPdz dPf l ow W h ere, dPavail = total avail ab l e driving h ead dPdz = p ressure h ead due to l iq uid l evel b etw een c ore inl et and outl et dPf l ow = p ressure h ead due to f l ow l osses in th e RCS T h e f l ow l osses ( dPf l ow ) f or eac h L OCA sc enario are b ased on th e val ues p rovided in L OCA anal y ses

( Ref erenc e [ 4-11] ) .

4.3.3.1 Availab le Driving H ead under the H ot-leg Break Condition In th e event of a h ot-l eg b reak , th e driving f orc e is th e m anom etric b al anc e b etw een th e l iq uid in th e dow nc om er and th e c ore, as sh ow n in Figure 4.3-2. If a deb ris b ed b egins to b uil d up in th e c ore, th e l iq uid l evel w il l b egin to b uil d in th e c ol d l egs and steam generators ( SGs) . As th e l evel b egins to rise in th e SG tub es, th e el evation h ead driving th e f l ow th rough th e c ore inc reases as w el l . T h e driving h ead reac h es its p eak w h en th e sh ortest SG tub e h as b een f il l ed.

Assum p tions

1) T h e c ore l iq uid l evel is assum ed to b e at th e b ottom of th e h ot l eg.

2) T h e dow nc om er l iq uid density is b ased on th e RCS p ressure. Sinc e density is inversel y p rop ortional to l iq uid tem p erature, and a l ow er density w il l reduc e th e driving h ead f rom th e dow nc om er, a c onservativel y h igh RCS tem p erature is sel ec ted. So, th e saturated w ater density 2 3 3 th e h igh est RCS p ressure of 3.312 k g/ c m A ( 47.113 p sia) is assum ed ( 929.15 k g/ m ( 58.0 l b m / f t ) ) .

2

3) T h e reac tor vessel dow nc om er and l ow er p l enum k / A is sm al l ( ty p ic al l y < < 0.1) . Furth er, th e 3 3 l iq uid density is l arge ( > 929.15 k g/ m ( 58.0 l b m / f t ) ) and b ul k vel oc ity is l ow . T h eref ore, th e l osses in th ese regions c an b e negl ec ted.

KEPCO & KHNP 75

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3

4) T o ac c ount f or th e p otential f or voiding in th e SG tub es, it is assum ed th at th e sip h on b reak oc c urs at th e b ottom of th e SG tub esh eet.

5) T h e f l ow l osses in reac tor c ore and l oop s are b ased on th e val ues in th e data f rom L OCA anal y ses.

Cal c ul ations TS T h e inp uts are f ound in APR1400 draw ings and eval uations. T h e val ues in T ab l e 4.3-3 are used to c al c ul ate th e h ot-l eg b reak avail ab l e h ead l oss. As stated in th e assum p tions, th e f l ow l osses in th e dow nc om er and l ow er are negl igib l e. T h eref ore, th e h ot-l eg dPavail ab l e is as f ol l ow s:

TS 4.3.3.2 Availab le Driving H ead under the Cold-leg Break Condition In th e event of a c ol d-l eg b reak , th e driving f orc e is th e m anom etric b al anc e b etw een th e l iq uid in th e dow nc om er and c ore, as sh ow n in Figure 4.3-3. T h e ECC w ater f rom eac h DV I l ine runs to th e b reak ,

ensuring th at th e dow nc om er is f ul l to at l east th e b ottom of th e c ol d-l eg noz z l es. T h e dPavail ab l e is estab l ish ed b y th e m anom etric b al anc e b etw een th e dow nc om er l iq uid l evel and th e c ore l iq uid l evel c onsidering th e p ressure drop th rough th e RCS l oop s due to th e steam f l ow .

Assum p tions

1) T h e assum p tions used in th e c ase of a h ot-l eg b reak ( assum p tions # 2, 3, 5) are al so ap p l ied to th e c ol d-l eg b reak c ase ex c l uding th e w ater density .

2

2) T h e saturated w ater density at th e h igh est RCS p ressure of 4.469 k g/ c m A ( 63.57 p sia) is 3 3 assum ed ( 919.59 k g/ m ( 57.41 l b m / f t ) ) .

Cal c ul ations TS T h e val ues in T ab l e 4.3-4 are used to c al c ul ate th e c ol d-l eg b reak avail ab l e h ead l oss. T h e dPavail f or a c ol d-l eg b reak is dep endent up on th e tim e at w h ic h th e val ue is c al c ul ated. T h eref ore, th e inp uts desc rib ed h ere c an b e used to c al c ul ate th e ex p ec ted dPavail as a f unc tion of tim e. Sinc e, th e b oil -of f rate dec reases w ith tim e, th e m inim um dPavail f or a c ol d-l eg b reak is c al c ul ated at th e rec irc ul ation start tim e KEPCO & KHNP 76

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3

( 700 sec onds.)

TS 4.3.3.3 Availab le Driving H ead under the Condition of Cold-leg Break af ter H LSO In th e event of a c ol d-l eg b reak af ter HL SO op eration, th e driving f orc e is th e m anom etric b al anc e b etw een th e l iq uid in th e dow nc om er and th e c ore, as sh ow n in Figure 4.3-4. If a deb ris b ed b egins to b uil d up in th e c ore, th e l iq uid l evel w il l b egin to b uil d in th e HL s and SGs. As th e l evel b egins to rise in th e SG tub es, th e el evation h ead driving th e f l ow th rough th e c ore inc reases as w el l . T h e driving h ead reac h es its p eak w h en th e sh ortest SG tub e h as b een f il l ed.

Assum p tions

1) T h e assum p tions used in th e c ase of a h ot-l eg b reak ( # 2, 5) are al so ap p l ied to th e c ase of a c ol d-l eg b reak af ter HL SO ex c l uding th e w ater density .

2) T h e HL SO op eration is assum ed to start at 1.5 h ours af ter a c ol d-l eg b reak f or th e earl iest tim e.

2

3) T h e saturated w ater density at th e h igh est RCS p ressure of 3.71 k g/ c m A ( 52.7 p sia) is assum ed 3 3

( 925.65 k g/ c m ( 57.78 l b m / f t ) ) .

Cal c ul ations TS T h e inp uts are f ound in APR1400 draw ings and eval uations. T h e val ues in T ab l e 4.3-4 are used to c al c ul ate th e avail ab l e h ead l oss f or a c ol d-l eg b reak af ter HL SO. T h e dPavail ab l e is as f ol l ow s:

TS 4.3.4 LOCADM Calculations T h is sec tion p rovides eval uation resul ts of tw o p aram eters ( c l adding tem p erature and c l adding dep osit th ic k ness) during th e 30 day p eriod f ol l ow ing a L OCA.

W CAP-16793-NP Revision 2, devel op ed b y th e PW R Ow ners Group ( PW ROG) , def ines an NRC ap p roved m eth odol ogy f or eval uating th e im p ac t of deb ris on l ong-term f uel c l adding p erf orm anc e sub seq uent to a L OCA. T h e m eth odol ogy and th e im p l em enting sof tw are, an Ex c el sp readsh eet b ased tool identif ied as th e L OCA Dep osition M odel ( L OCADM ) , is used to eval uate th e ef f ec t f rom dep osition of c h em ic al sp ec ies c arried into th e c ore b y saf ety inj ec tion c ool ant, on th e f uel and th e resul tant c l adding tem p eratures. T h e c h em ic al -ef f ec ts-m odel ing m eth ods devel op ed in ( Ref erenc e [ 3-11] ) are used in th e L OCADM m eth ods to determ ine th e ty p es and c onc entrations of th e c h em ic al sp ec ies p resent in th e saf ety inj ec tion c ool ant.

KEPCO & KHNP 77

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 L OCADM uses a c onservative m odel f or dec ay h eat generation and h eat rem oval to eval uate l oc al c ore b oil ing and th e sub seq uent dep osition of dissol ved sol ids on th e surf ac es of f uel rods. T h e c om b ination of dep osit th ic k ness and c onduc tivity , c ool ant tem p erature and l oc al iz ed dec ay h eat generation are th en used to determ ine c l adding tem p erature th rough out th e duration of a L OCA event.

L OCADM is used w ith th e m eth odol ogy p rovided in Ref erenc e [ 4-7] and th e guidanc e p rovided in

( Ref erenc e [ 4-8] ) to eval uate c l adding-dep osit th ic k ness and tem p erature.

4.3.4.1 Acceptance Bases T h e f ol l ow ing ac c ep tanc e b ases are sel ec ted f or th e eval uation ac c ording to th e W CAP-16793-NP:

1) T h e m ax im um c l ad tem p erature sh al l not ex c eed 800 ° F.

2) T h e th ic k ness of th e c l adding ox ide and th e dep osits of m aterial on th e f uel sh al l not ex c eed 0.050 inc h in any f uel region.

4.3.4.2 M ethodology W CAP-16793-NP Revision 2 w as devel op ed b y th e PW ROG to eval uate th e l ong-term ef f ec t of c h em ic al sp ec ies generated in th e c ontainm ent IRW ST environm ent f rom p artic ul ate, f ib rous and c h em ic al deb ris generated during th e L OCA and transp orted into th e c ore b y saf ety inj ec tion c ool ant. Sp ec if ic to th is eval uation m eth odol ogy , th e PW ROG devel op ed a L OCADM th at im p l em ents c h em ic al dissol ution and dep osition m odel s f or c onservativel y eval uating tw o p aram eters c ritic al to l ong-term c ool ing: c l adding dep osit th ic k ness and c l adding tem p erature. T h ese p aram eters are c om p ared w ith NRC ac c ep ted c riteria to determ ine if l ong-term c ool ing req uirem ents are m et, b ased on p l ant-sp ec if ic inp uts and deb ris l oads.

T h e f ol l ow ing doc um ents p rovide th e p rim ary guidanc e in th e ap p l ic ation of a L OCADM :

1) W CAP-16793-NP Revision 2, Sec tion 7, Ap p endix E

2) NRC SE f or W CAP-16793-NP Revision 2

3) OG-07-419 ( Ref erenc e [ 4-12] ) transm itting L OCADM .x l s w ith som e disc ussion of sel ec ted inp ut p aram eters

4) OG-07-534 ( Ref erenc e [ 4-13] ) p roviding disc ussion of Op tions 1 and 2 f or m odel ing M odes 1 and 2

5) OG-08-64 ( Ref erenc e [ 4-14] ) p roviding guidanc e to address an NRC c onc ern th at sh ort term al um inum rel ease is under p redic ted b y th e L OCADM L OCADM eval uates c onditions during th e event th rough th e f our p l ant op erating m odes during a L OCA event ( Ref erenc e [ 4-13] ) :

1) M ode 1: B l ow dow n/ Ref il l b l ow dow n of w ater f rom th e RCS as a c onseq uenc e of th e b reak ,

ref il l of th e vessel b y inj ec tion f rom th e saf ety inj ec tion tank s and IRW ST

2) M ode 2: Af ter vessel ref il l b ut b ef ore rec irc ul ation b egins

3) M ode 3: Rec irc ul ation f rom th e IRW ST KEPCO & KHNP 78

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3

4) M ode 4: Hot l eg inj ec tion Figure 4.3-5 sh ow s th e sc h em atic diagram of th e L OCADM p h y sic al m odel . T h e sc h em atic sh ow s th e reac tor vessel w ith th e RCS b reak , th e c ore, th e c ontainm ent and IRW ST . T h e f ol l ow ing def initions are p rovided:

1) B reak Fl ow - ref l ec ts c ool ant th at drains direc tl y f rom th e RCS b reak

2) B OPB l ow dow n - c ool ant th at f l ow s f rom th e oth er p arts of th e p l ant b ac k into th e reac tor vessel and c ontainm ent

3) RV L q Fl ow - c ool ant th at drains f rom th e reac tor vessel th rough th e RCS b reak

4) RV Steam Fl ow - steam th at vents f rom th e RCS to c ontainm ent th rough th e RCS b reak

5) T SPFl ow - tri-sodium p h osp h ate f l ow into th e IRW ST

6) Sp ray Fl ow - c ontainm ent sp ray draw n f rom th e IRW ST

7) SIFl ow - saf ety inj ec tion f l ow th at is draw n f rom th e IRW ST and inj ec ted into th e intac t l oop ( i.e.,

Cl eanSIFl ow ) and into th e b rok en l oop ( i.e., Cl eanB y p ass )

8) T h e rec irc ul ation f l ow draw n f rom th e IRW ST inc l udes rec irc ul ation w ater inj ec ted into th e intac t l oop ( i.e., Rec irc L q Fl ow ) and th e b rok en l oop ( i.e., Rec irc B y p ass )

4.3.4.3 Assumptions T h e f ol l ow ing assum p tions h ave b een m ade regarding inp uts to p rovide a c onservative eval uation.

1) It is assum ed th at al l al um inum ex p osed to c ontainm ent sp ray , and sub m erged in th e IRW ST sum p s, is p ure unal l oy ed al um inum ( i.e., Al l oy 1100) .

3 3 3

2) It is assum ed th at 0.36 m ( 12.5 f t ) of f ib er deb ris ( a density of 0.038 g/ c m ( 2.4 l b m / f t³ ) )

b y p asses th e ECCS sum p strainers, and is entrained in th e saf ety inj ec tion and rec irc ul ation f l ow s.

B asis: T h ere is no f ib er insul ation inside th e Z OI. Onl y l atent f ib er am ount is assum ed to b e 6.80 k g ( 15 l b m ) inside th e entire c ontainm ent. How ever, 13.6 k g ( 30 l b m ) of l atent f ib er is assum ed to b y p ass th e ECCS sum p strainers f or c onservatism .

3) It is assum ed th at M ode 3 f or rec irc ul ation inj ec tion f rom th e IRW ST b egins at 700 sec onds.

4) It is assum ed th at M ode 4 f or h ot-l eg sw itc h over inj ec tion f rom th e IRW ST b egins at 5,225 sec onds ( 1.45 h ours) .

4.3.4.4 Inputs APR1400 sp ec if ic inp uts used in th e L OCADM eval uations are disc ussed b el ow .

KEPCO & KHNP 79

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 4.3.4.4.1 T ime-Input Guidanc e f or inp ut to p op ul ate th e T im e-Inp ut w ork sh eet c om es p rim aril y f rom th e Instruc tions w ork sh eet in th e L OCADM sp readsh eet. T h e inp ut c onsists p rim aril y of tim es during, and sub seq uent to, th e L OCA, th e c orresp onding f l uid tem p eratures and f l ow s, and th e p l ant-op erating m ode.

T im e, sec onds In order to m odel th e start of rec irc ul ation at 700 sec onds p ost-L OCA and 1.45 h ours p ost-L OCA, tim e step s are added to th e b ase w ork sh eet at a) 700 and 701 sec onds, and b ) 5,224 and 5,225 sec onds.

T h e c al c ul ations h ave b een ex ec uted w ith a m ission tim e of 30 day s c onsistent w ith W CAP-16793-NP m eth odol ogy .

IRW ST p H T h e IRW ST p H p rof il e is assum ed to b e p H 10 f or th e f irst 4 h ours p ost-L OCA, and p H 8.5 th ereaf ter.

T h e use of th e h igh er val ues is c onservative as a h igh er p H enh anc es dissol ution of deb ris in th e IRW ST ,

th ereb y generating l arger sc al e th ic k ness and sl igh tl y h igh er c l adding tem p eratures.

IRW ST T em p erature, ° C ( ° F)

T h e IRW ST tem p erature p rof il e used f or th is c al c ul ation is sh ow n in T ab l e 4.3-6.

Sp ray Fl ow , k g/ sec ( l b m / sec )

T h e c ontainm ent sp ray f l ow , in ac c ordanc e w ith th e guidanc e p rovided ( Ref erenc e [ 4-13] ) f or L OCADM Op tion 2 op eration, is set to z ero f or al l inp ut tim es.

Sp ray p H T h e c ontainm ent-sp ray p H p rof il e is set to p H 10.0 f or th e f irst 4 h ours p ost-L OCA, and p H 8.5 th ereaf ter.

As disc ussed ab ove, th e use of th e h igh er val ues is c onservative as a h igh er p H enh anc es dissol ution of deb ris in th e IRW ST and c om p onents w etted b y th e IRW ST f l uid, th ereb y generating l arger sc al e th ic k ness and sl igh tl y h igh er c l adding tem p eratures.

Reac tor V essel Cool ant T em p erature, ° C ( ° F)

T h e RV c ool ant tem p erature is assum ed to c al c ul ate th e RV p ressure w h ic h is sh ow n in DCD T ier 2, T ab l e 6.2.1-7 Part B . T h e tem p erature p rof il e is sh ow n in T ab l e 4.3-6.

Cl ean Saf ety Inj ec tion Fl ow into Reac tor V essel , k g/ sec ( l b m / sec )

T h e c l ean saf ety inj ec tion f l ow is set to z ero f or M odes 1, 3, and 4. T h e c l ean saf ety inj ec tion f l ow f or M ode 2 is ob tained f rom th e m ax im um steam ing rate.

Rec irc ul ation Fl ow into Reac tor V essel , k g/ sec ( l b m / sec )

T h e rec irc ul ation f l ow into th e reac tor vessel , in ac c ordanc e w ith th e guidanc e p rovided ( Ref erenc e [ 4-13] )

f or L OCADM Op tion 2 op eration is set to:

1) 0 f or M odes 1 and 2

2) th e Reac tor V essel Steam Fl ow ( i.e., Col um n V ) f or M ode 3 KEPCO & KHNP 80

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3

3) th e c al c ul ated rec irc ul ation f l ow f or M ode 4 T SP Dissol ution Rate, k g/ sec ( l b m / sec )

W h il e th e APR1400 im p l em ents T SP f or IRW ST c ool ant p H c ontrol , its im p ac t on IRW ST p H is ac c ounted f or in th e IRW ST c ool ant p H p rof il e. T h eref ore, th e T SP dissol ution rate is unused and th e val ue is set to 0 .

3 Reac tor V essel Pressure in U p p er Pl enum , k g/ c m ( p sia)

Ref erenc e [ 4-13] , indic ates th at th e saturation p ressure at th e reac tor c ool ant tem p erature sh oul d b e entered until th e saturation p ressure f al l s b el ow th e c ontainm ent p ressure, at w h ic h p oint th e c ontainm ent p ressure sh oul d b e entered. V al ues p rovided f or Reac tor V essel Pressure in U p p er Pl enum are eval uated internal l y b y L OCADM . For c onservatism , c al c ul ated sub -atm osp h eric p ressures are reset to 1 atm ( 14.7 p sia) .

M ax im um Steam ing Rate, l b m / sec T h e M ax im um Steam ing Rate is eval uated internal l y in L OCADM . T h e c al c ul ated val ues are not overw ritten and rem ain as c al c ul ated.

4.3.4.4.2 M aterials Input Guidanc e f or inp ut to p op ul ate th e M aterial s Inp ut w ork sh eet c om es p rim aril y f rom th e Instruc tions w ork sh eet in th e L OCADM sp readsh eet itsel f . T h e inp ut c onsists p rim aril y of m aterial ty p es, th eir surf ac e areas or vol um es, and/ or m asses.

M etal l ic Al um inum Al l oy 1100 or U nk now n Al l oy T y p e As th e sp ec if ic al um inum al l oy h as not b een sp ec if ied, inf orm ation regarding sub m erged and unsub m erged al um inum is entered as M etal l ic Al um inum Al l oy 1100 or U nk now n Al l oy T y p e .

TS 2

1) al um inum sub m erged ( m / f t² )  :

2) al um inum sub m erged ( k g / l b m )  :

2

3) al um inum not sub m erged ( m / f t² ) :

4) al um inum not sub m erged ( k g / l b m ) :

Cal c ium Sil ic ate T h is m aterial ty p e inc l udes l ow density c al c ium sil ic ate m at insul ation, asb estos and asb estos-c ontaining insul ation, and h igh density ref rac tory m aterial s ( e.g., transite) . How ever, no c al c ium sil ic ate m aterial s are used in th e APR1400.

E-Gl ass T h is m aterial ty p e inc l udes f ib ergl ass insul ation.

3 3

- Fib ergl ass insul ation : 0.36 m ( 12.5 f t )

3 3 3 U sing a density of 0.038 g/ c m ( 2.4 l b m / f t³ ) , a val ue of 0.36 m ( 12.5 f t ) is entered f or Fib ergl ass KEPCO & KHNP 81

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Insul ation .

Conc rete Ex p osed c onc rete surf ac es in c ontainm ent are inp ut to al l ow c onsideration of c h em ic al l eac h ing and 2 2 dissol ution. 868.1 m ( 9,344 f t² ) of c onc rete is ex p osed in c ontainm ent. In th e L OCADM inp ut, 1,736 m 2

( 18,688 f t ) w as used b y ap p l y ing th e b um p -up f ac tor of 2.

Cool ant Cool ant m aterial inp uts are p rovided to sp ec if y c ool ant sp ec if ic c h arac teristic s f or inp ut to L OCADM .

T ab l e 4.3-7 and T ab l e 4.3-8 sum m ariz e th e c ontainm ent m aterial inp uts and c ool ant m aterial inp uts, resp ec tivel y .

4.3.4.4.3 M aterials Conversions Guidanc e f or inp ut to p op ul ate th e M aterial s Conversions w ork sh eet c om es p rim aril y f rom th e Instruc tions w ork sh eet in th e L OCADM sp readsh eet. T h e inp ut c onsists p rim aril y of m aterial densities w ith m aterial am ounts draw n f rom th e w ork sh eet M aterial s Inp ut and m ul tip l ied b y th e density val ues to generate th e m aterial m asses ( in k g) and total m aterial c l ass m asses ( in k g) . T h e IRW ST w ater density 3

is assum ed to b e 0.93 g/ c m ( 57.9 l b m / f t³ ) .

4.3.4.4.4 Spreadsheet Core-Data-Input Guidanc e f or inp ut to p op ul ate th e Core-Data-Inp ut w ork sh eet c om es p rim aril y f rom th e Instruc tions w ork sh eet in th e L OCADM sp readsh eet. T h e inp ut is entered into th ree dif f erent m atric es th e inp ut used f or th is is disc ussed b el ow .

4.3.4.4.4.1 Summary of Core and Fuel Characteristics Gl ob al c h arac teristic s f or th e reac tor c ore and f uel are p rovided in th is m atrix .

100% Reac tor Pow er ( M W T h erm al )

T h e c ore th erm al p ow er is 3,983 M W th .

Crud T h erm al Conduc tivity ( W / m K)

Page E-16 of Ref erenc e [ 4-7] indic ates th at th e l im iting val ue f or th e th erm al c onduc tivity of PW R c rud is 0.52 W / m K. T h is val ue is inp ut f or Crud T h erm al Conduc tivity f or th e L OCADM eval uations.

L OCA Dep osit T h erm al Conduc tivity ( W / m K)

Page E-16 of Ref erenc e [ 4-7] indic ates th at th e l im iting val ue f or th e th erm al c onduc tivity of p ost-L OCA dep osits is 0.2 W / m K. T h is val ue is inp ut f or L OCA Dep osit T h erm al Conduc tivity f or th e L OCADM eval uations.

Fuel Rod OD ( inc h )

A val ue of 9.50 m m ( 0.374 inc h ) is used.

KEPCO & KHNP 82

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Pel l et Stac k L ength ( inc h )

A val ue of 3.81 m ( 150 inc h ) is used.

Average Cl adding Ox ide T h ic k ness ( m ic rons)

As disc ussed in Ref erenc es [ 4-8] and [ 4-12] , th e average initial f uel ox ide th ic k ness is eval uated b y assum ing th e m ax im um ex tent of c l adding ox idation as p er 10CFR50.46 ( i.e., 17% ) and m ul tip l y ing b y 1.56. For th ese anal y ses, th e p eak initial ox ide th ic k ness is determ ined to b e:

Ox ide initial = 0.02252x0.17x1.56 x

-3 m m ( 5.97x 10 inc h )

For c onservative eval uation, th e average c l adding-ox ide th ic k ness is c onsidered to b e th e sam e as p eak

-3 m ( 5.97x 10 inc h ) .

Average Starting Crud T h ic k ness ( m ic rons)

Ref erenc e [ 4-13] indic ates th at th e val ue inp ut f or Average Starting Crud T h ic k ness is th e m ax im um

-3 b ound m ( 5.51x 10 inc h ) , m ul tip l ied b y th e m ax im um val ues of th e Rel ative Crud T h ic k ness m ul tip l iers in th e ax ial and f uel region m atric es. For c onservative eval uation, th e average

-3 initial c rud th ic k ness is c onsidered to b e th e sam e as th e m ax im um b ound m ( 5.51x 10 inc h ) .

Num b er of Regions Ref erenc e [ 4-7] p rovides guidanc e on th e num b er of c ore regions to b e used in th e L OCADM anal y ses.

T ab l e E-1 indic ates th at th is inp ut p aram eter is to b e set to 3 f or CE ty p e NSSSs. T h is nodal iz ation is m aintained f or th e L OCADM anal y ses doc um ented in th is c al c ul ation.

Num b er of Ax ial Nodes Ref erenc e [ 4-13] indic ates in T ab l e 9, th at th is inp ut p aram eter sh oul d b e set to 3 . T h is is m aintained f or th e L OCADM anal y ses doc um ented in th is c al c ul ation.

Distanc e f rom Hot L eg Inl et to T op of Pel l et Stac k ( inc h )

T h e distanc e f rom th e top of th e ac tive region to th e b ottom of th e h ot l eg inl et is 1.01 m ( 39.748 inc h ) .

4.3.4.4.4.2 Core (Ax ial) Elevation Characteristics Ref erenc e [ 4-13] , T ab l e 9, p rovides rec om m ended val ues f or al l p l ant ty p es. T h ese val ues h ave b een inp ut f or th e L OCADM c ases ex ec uted f or th e APR1400. Param eter variations as a f unc tion of ax ial p osition are p rovided in T ab l e 4.3-10.

4.3.4.4.4.3 Fuel Region (Radial) Characteristics Ref erenc e [ 4-7] , T ab l e E-1, p rovides rec om m ended val ues f or th e num b er of rods p er region and th e rel ative p ow er f rac tion f or al l U S PW R p l ant ty p es. V al ues sp ec if ic to a CE reac tor design using a 16x 16 f uel -array are p rovided. T h e sp ec if ic val ues inp ut to L OCADM are sum m ariz ed in T ab l e 4.3-11 al ong w ith th e b ases f or th ose p artic ul ar num b ers.

KEPCO & KHNP 83

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Region Consistent w ith CE NSSSs im p l em enting 16x 16 f uel -array designs, th ree radial c ore regions are m odel ed.

T h is nodal iz ation is m aintained f or th e APR1400 L OCADM anal y ses doc um ented in th is T ec h nic al Rep ort.

Rel ative Pow er, Num b er of Rods Ref erenc e [ 4-7] , T ab l e E-1, p rovides rec om m ended val ues of th e num b er of rods p er region and th e rel ative p ow er f rac tion f or al l p l ant ty p es. V al ues sp ec if ic to a CE reac tor design using a 16x 16 f uel -array h ave b een used in L OCADM eval uation. T h e total num b er of f uel rods sp ec if ied f or Regions 1-3, sum s to 56,876. T h is c orresp onds to 241 assem b l ies c om p rised of a 16x 16 l attic e th at h as 20 rods rep l ac ed b y c ontrol rods and instrum entation th im b l es ( i.e., a net of 236 f uel rods p er assem b l y ) .

4.3.4.4.5 Spreadsheet Sw itches Guidanc e f or inp ut to p op ul ate th e Sw itc h es w ork sh eet c om es p rim aril y f rom th e Instruc tions w ork sh eet in th e L OCADM sp readsh eet. T h e sw itc h es p erm it f ac toring in reduc tions in th e p roj ec ted c h em ic al ef f ec ts b y c rediting inh ib ition of c orrosion and/ or sol ub il ity l im its.

4.3.4.5 Results TS In c onc l usion, th e m ax im um total dep osit th ic k ness and th e p eak c l adding tem p erature are m aintained w ith in ac c ep tanc e b ases p rovided in Ref erenc e [ 4-7] w ith suf f ic ient m argin.

4.3.5 Boric Acid Precipitation T h e APR1400 design uses b oron to c ontrol c ore reac tivity , and is sub j ec t to c onc erns regarding p otential p ost-L OCA b oric ac id p rec ip itation ( B AP) in th e c ore. T o p revent th e c ore region b oric ac id c onc entration f rom reac h ing th e p rec ip itation p oint, th ere is a p roc edure th at instruc ts th e op erators to initiate a h ot-l eg sw itc h over op eration w ith in 2 h ours af ter a c ol d-l eg b reak ( Ref erenc e [ 4-9] ) .

T h ere are additional c onc erns ab out th e p otential f or deb ris in th e c ore to c h ange f l ow p atterns or oth erw ise inh ib it th e m ix ing of b oric ac id th at c oul d resul t in earl ier B AP. Deb ris b eds w ith in th e c ore c oul d b l oc k th e c ool ant c h annel s and inh ib it c ore c ool ing w h en h igh er am ounts of f ib er are invol ved.

T o address th ese c onc erns on h igh er f ib rous-deb ris l oads, th e APR1400 is designed as a l ow f ib er p l ant b y ex c l usion of f ib rous m aterial w ith in th e z one of inf l uenc e of a h igh -energy l ine b reak . T h e m ax im um T S antic ip ated f ib rous-deb ris l oad f or a c ol d-l eg b reak is ab out [ ] gram s p er f uel assem b l y ( Sec tion 4.3.2.2) . T h is is l ess th an th e 7.5 gram s ( 0.017 l b m ) l im it ac c ep ted b y th e NRC ( Ref erenc e [ 4-8] ) .

T h eref ore, it is c onc l uded th at th e deb ris ingested b y th e reac tor vessel w oul d not signif ic antl y af f ec t th e m ix ing c ap ab il ity of b oric ac id in th e APR1400.

4.3.6 Fuel Assemb ly T esting APR1400 f uel -assem b l y tests h ave b een p erf orm ed to c onf irm th at th e h ead l osses c aused b y deb ris KEPCO & KHNP 84

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 dep osited on a f uel assem b l y , m eet th e avail ab l e driving h ead f ol l ow ing a L OCA.

In th is test, various ranges of deb ris am ounts ( 15 g ( 0.033 l b m ) of f ib er, 900 g ( 1.984 l b m ) of p artic ul ates, and 768 g ( 1.693 l b m ) of c h em ic al deb ris) are ap p l ied. T h e testing rep resents th at th e p artic l e-to-f ib er ratio of 1 p roduc es th e h igh est p ressure drop f or c onstant f ib er l oading under th e h ot-l eg b reak c ondition, and 50 under c ol d-l eg b reak c ondition. T h e p resenc e of c h em ic al deb ris c auses an additional inc rease in th e overal l p ressure drop . How ever, af ter som e am ount of c h em ic al deb ris is added, sub seq uent c h em ic al deb ris does not inc rease th e p ressure drop . A sum m ary of test resul ts is p resented in T ab l e 4.3-12.

T S T h e p ressure drop c riterion of th e h ot l eg-b reak c ondition is [ ] k Pa. Al l th e test resul ts sh ow l ow er T S p ressure drop th an th e ac c ep tanc e c riterion, and th e h igh est p ressure-drop is [ ] k Pa. T h e T S p ressure drop ac c ep tanc e c riterion f or th e c ol d-l eg b reak c ondition is [ ] k Pa, and th e h igh est T S p ressure drop is [ ] k Pa. Figures 4.3-8 and 4.3-9 p resent th e p ressure-drop s f or h ot-l eg b reak and c ol d-l eg b reak tests, w h ic h give th e l im iting resul ts. Detail ed desc rip tions of th e test resul ts are f ound in

( Ref erenc e [ 4-10] ) .

T h eref ore, a suf f ic ient driving f orc e is avail ab l e to m aintain an adeq uate f l ow rate, and th e l ong-term c ore c ool ing c ap ab il ity is adeq uatel y m aintained in th e APR1400.

4.3.7 Evaluation Summary T h e intent of th is sec tion is to assess th e in-vessel dow nstream ef f ec ts of th e APR1400, b y ap p l y ing th e eval uation m eth ods and ac c ep tanc e b ases p rovided in Ref erenc e [ 4-7] and [ 4-8] .

T o rem ain w ith in th e 15 gram ( 0.033 l b m ) / FA f ib er l im it, th ere is no f ib rous insul ation w ith in th e Z OI. T h e eval uation resul ts of th e APR1400 in-vessel dow nstream ef f ec ts are:

1) Fol l ow ing a L OCA, th e ECC f l ow rate p er FA is 78 L / m in ( 20.5 gp m ) f or th e h ot-l eg b reak c ondition, and 14 L / m in ( 3.64 gp m ) f or th e c ol d-l eg b reak c ondition.

2) T h e am ount of b y p ass f ib er p er FA is l ess th an th e 15 gram ( 0.033 l b m ) l im it.

TS

5) T h e deb ris ingested b y th e reac tor vessel w oul d not signif ic antl y af f ec t th e m ix ing c ap ab il ity of b oric ac id in th e APR1400.

6) A suf f ic ient driving f orc e is avail ab l e to m aintain an adeq uate f l ow rate, and th e l ong-term c ore c ool ing c ap ab il ity is adeq uatel y m aintained in th e APR1400 In c onc l usion, suf f ic ient l ong-term c ore c ool ing f ol l ow ing a L OCA in th e APR1400 is ac h ieved, given th e p resenc e of th e range of deb ris and c h em ic al p roduc ts p ostul ated to b e transp orted to th e reac tor vessel .

KEPCO & KHNP 85

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.1-1 Strainer Fl ow Rate and Deb ris L oads Pl ant Strainer Prototy p e Strainer Fl ow Rate Strainer Pum p s Deb ris L oads Deb ris L oad

( L / m in / gp m )

( k g/ lb m ) ( k g/ lb m )

1 SIP + CSP 25,211 / 6,660 2.87 / 6.33 0.36 / 0.79 2 SIP + CSP 25,211 / 6,660 2.87 / 6.33 0.36 / 0.79 3 SIP 4,675 / 1,235 0.53 / 1.17 0.07 / 0.15 4 SIP 4,675 / 1,235 0.53 / 1.17 0.07 / 0.15 T otal 59,772 / 15,790 6.80 / 15.0 0.85 / 1.88 KEPCO & KHNP 87

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.1-2 B y p ass Fib er W eigh t Cum ul ative B y p ass Deb ris L oad Fib er Added B y p ass Fib er W eigh t Fib er W eigh t Addition ( g/ lb m ) ( g/ lb m )

( g/ lb m )

Af ter f irst f ib er 181.2 / 0.40 37.16 / 0.08 37.16 / 0.08 addition Af ter sec ond f ib er 181.2 / 0.40 29.66 / 0.07 66.82 / 0.15 addition Af ter th ird f ib er 181.2 / 0.40 28.04 / 0.06 94.86 / 0.21 addition Af ter f ourth f ib er 181.2 / 0.40 29.08 / 0.06 123.94 / 0.27 addition KEPCO & KHNP 88

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.1-3 B y p ass Deb ris Q uantities of IRW ST Sum p Strainer Pl ant Prototy p e Fl ow Prototy p e Strainer Strainer Ratio of B y p assed Rate B y p ass Strainer Pum p s Deb ris Deb ris Surf ac e Fib er M ass

( L / m in / Deb ris L oads L oad Areas ( k g/ lb m )

gp m ) ( k g/ lb m )

( k g/ lb m ) ( k g/ lb m )

SIP + 25,211 / 0.067 /

1 2.87 / 6.33 0.36 / 0.79 8.0 0.54 / 1.18 CSP 6,660 0.1475 SIP + 25,211 / 0.067 /

2 2.87 / 6.33 0.36 / 0.79 8.0 0.54 / 1.18 CSP 6,660 0.1475 4,675 / 0.037 /

3 SIP 0.53 / 1.17 0.07 / 0.15 8.0 0.30 / 0.66 1,235 0.082 4,675 / 0.037 /

4 SIP 0.53 / 1.17 0.07 / 0.15 8.0 0.30 / 0.66 1,235 0.082 59,772 / 0.208 /

T otal 6.80 / 15.0 0.85 / 1.88 - 1.67 / 3.68 15,790 0.459 KEPCO & KHNP 89

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-1 Com p onents in th e Fl ow Path during an L B L OCA ( 1 of 3)

Com p onent Desc rip tion Pumps T y p e: m ul ti-stage c entrif ugal p um p SI p um p Arrangem ent: h oriz ontal

( SI-PP02A/ 02B / 02C/ 02D) ( 1)

Fl ow rate: ~ 4,675 L / m in ( 1,235 gp m ) ( m ax im um )

T y p e: c entrif ugal CS Pum p Arrangem ent: vertic al

( CS-PP01A/ 01B ) ( 1)

Fl ow rate: ~ 24,605 L / m in ( 6,500 gp m ) ( m ax im um )

H eat Ex changers T y p e: sh el l and tub e, U -tub e, h oriz ontal l y m ounted Num b er of sh el l in series: 1 CS Heat Ex c h anger Num b er of tub e p asses: 2

( CS-HE01A/ 01B ) T ub e m aterial ; austenitic steel Fl ow rate: ~ 18,927 L / m in ( 5,000 gp m ) ( during L B L OCA Containm ent Sp ray )

T y p e: sh el l and tub e, U -tub e, h oriz ontal l y m ounted Num b er of sh el l in series: 1 CS Pum p M inif l ow Heat Ex c h anger Num b er of tub e p asses: 2

( CS-HE02A/ 02B )

T ub e m aterial ; austenitic steel Fl ow rate: ~ 1,817 L / m in ( 480 gp m )

V alves CS-V 1001/ 1002 Sw ing c h ec k , 14 inc h CS-V 1003/ 1004 Gate ( m anual ) , 14 inc h CS-V 1007/ 1008 Sw ing c h ec k , 14 inc h CS-V 1015/ 1016/ 1017/ 1018 Gl ob e ( m anual ) , 4 inc h CS-V 001/ 002/ 003/ 004 Gate ( M OV ) , 14 inc h SI-V 304/ 305 Gate ( M OV ) , 20 inc h SI-V 470/ 402/ 130/ 131 Gate ( m anual ) , 10 inc h SI-V 404/ 405/ 434/ 446 Sw ing c h ec k , 4 inc h SI-V 435/ 447/ 476/ 478 Gate ( m anual ) , 4 inc h SI-V 308/ 309 Gate ( M OV ) , 20 inc h SI-V 347/ 348 Gate ( M OV ) , 18 inc h SI-V 157/ 158 Sw ing c h ec k , 18 inc h SI-V 424/ 426/ 448/ 451 Sw ing c h ec k , 4 inc h SI-V 410/ 411/ 412/ 413 Gl ob e ( m anual ) , 4 inc h SI-V 302 Gate ( m anual ) 4 inc h SI-V 303 Gl ob e ( M OV ) , 4 inc h SI-V 100/ 101 Sw ing c h ec k , 10 inc h SI-V 395 Gate ( M OV ) , 10 inc h SI-V 959 Gate ( m anual ) , 10 inc h SI-V 604/ 609 Gate ( M OV ) , 4 inc h Note :

( 1) Inc l uding m inim um b y p ass f l ow KEPCO & KHNP 90

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-1 Com p onents in th e Fl ow Path during an L B L OCA ( 2 of 3)

Com p onent Desc rip tion V alves (Cont.)

SI-V 616/ 626/ 636/ 646 Gl ob e ( M OV ) , 4 inc h SI-V 113/ 133 Sw ing c h ec k , 4 inc h SI-V 123/ 143 Sw ing c h ec k , 12 inc h SI-V 540/ 542 Sw ing c h ec k , 4 inc h SI-V 541/ 543 Sw ing c h ec k , 12 inc h SI-V 614/ 624/ 634/ 644 Gate ( M OV ) , 12 inc h SI-V 217/ 227/ 237/ 247 Sw ing c h ec k , 12 inc h SI-V 321/ 331 Gl ob e ( M OV ) , 4 inc h SI-V 523/ 533 Sw ing c h ec k , 4 inc h SI-V 957/ V 958 Gate ( m anual ) , 4 inc h SI-V 522/ 532 Sw ing c h ec k , 4 inc h Orif ice CS-OR01A/ B CS p um p m inif l ow orif ic e, 4 inc h CS-FE338/ 348 CS p um p outl et f l ow instrum ent orif ic e, 14 inc h CS-02A/ B , 03A/ B CS m ain sp ring ring h eader orif ic e, 8 inc h CS-OR04A/ B CS m ain sp ring ring h eader orif ic e, 4 inc h CS-OR05A/ B , 06A/ B CS aux il iary sp ring ring h eader orif ic e, 4 inc h SI-OR01A/ B / C/ D, 08A/ B / C/ D, 20A/ B / C/ D SI p um p m inif l ow orif ic e, 4 inc h SI-OR06A/ B / C/ D SI p um p outl et f l ow orif ic e, 4 inc h SI-OR07A/ B Hotl eg inj ec tion f l ow orif ic e, 4 inc h SI-FE311D/ 321B / 331C/ 341A SI p um p outl et f l ow instrum ent orif ic e, 4 inc h SI-FE390C/ 391D Hotl eg inj ec tion f l ow instrum ent orif ic e, 4 inc h Containment Spray Noz z le M ain sp ray noz z l e Orif ic e siz e 13.1 m m ( 0.516 inc h )

Aux il iary sp ray noz z l e Orif ic e siz e 5.6 m m ( 0.22 inc h )

Piping 18 inc h CS p um p suc tion l ine ( SS Sc h . 80) 16 inc h CS p um p suc tion l ine ( SS Sc h . 80) 14 inc h CS p um p disc h arge l ine ( SS Sc h . 80) 12 inc h CS p um p disc h arge l ine ( SS Sc h . 80S) 14 inc h CS sp ray h eader l ine ( SS Sc h . ST D) 12 inc h CS sp ray h eader l ine ( SS Sc h . 40S) 8 inc h CS sp ray h eader l ine ( SS Sc h 40S) 6 inc h CS sp ray ring l ine ( SS Sc h 40S) 4 inc h CS sp ray ring l ine ( SS Sc h 40S) 4 inc h CS p um p m inif l ow l ine ( SS Sc h 40) 10 inc h SI IRW ST return l ine ( SS Sc h 120) 24 inc h SI p um p suc tion l ine ( SS Sc h . 80) 20 inc h SI p um p suc tion l ine ( SS Sc h . 80) 10 inc h SI p um p suc tion l ine ( SS Sc h . 80S) 4 inc h SI p um p disc h arge l ine ( SS Sc h . 120) 4 inc h SI p um p m inif l ow l ine ( SS Sc h . 120) 4 inc h SI p um p h ot l eg Inj ec tion l ine ( SS Sc h . 120)

KEPCO & KHNP 91

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-1 Com p onents in th e Fl ow Path during an L B L OCA ( 3 of 3)

Com p onent Desc rip tion Piping (Cont.)

4 inc h SI p um p disc h arge l ine ( SS Sc h . 160) 12 inc h SI p um p disc h arge l ine ( SS Sc h . 160)

KEPCO & KHNP 92

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-2 Siz e Range of Deb ris M aterial s Deb ris Siz e Category Siz e Partic ul ates 0 - 2.38 m m ( 0 - 0.094 inc h )

Fines < 101.6 m m ( 4 inc h )

L arge p iec es > 101.6 m m ( 4 inc h )

KEPCO & KHNP 93

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-3 T otal Q uantity of Deb ris Generated during an L B L OCA Deb ris Sourc e Partic ul ate Fines L arge Piec es T otal TS 3 3 RM I ( m / ft)

Q ual if ied ep ox y c oating ( 1) 132.2 / 291.4 0 0 132.2 / 291.4

( k g/ lb m )

Partic ul ate 83.9 / 185 0 0 83.9 / 185 L atent deb ris

( k g/ lb m )

Fib ers 0 6.8 / 15 0 6.8 / 15 2 2 ( 2)

M isc el l aneous ( m / ft) 0 0 - 0 Note :

3

( 1) For strainer design, ep ox y c oating of 3.10 f t is c onservativel y used.

2 2

( 2) T o deal w ith th e q uantity of m isc el l aneous deb ris, a 9.29 m ( 100 f t ) p enal ty of sac rif ic ial strainer surf ac e area p er sum p is ap p l ied.

KEPCO & KHNP 94

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-4 T erm inal Settl ing V el oc ity of Deb ris Sourc e M aterial s T erm inal Settl ing Deb ris Sourc e M aterial V el oc ity Ref erenc e/ Com m ents

( m / s / f t/ s)

Q ual if ied ep ox y c oatings 0.046 / 0.15 NEI 04-07 ( p age 4-34, ep ox y )

T h e term inal settl ing vel oc ity of l atent deb ris

( 1) is estim ated rel ative to th e settl ing vel oc ity of L atent deb ris 0.213 / 0.70 th e c onstituent l atent p artic ul ate estim ated in Sub sec tion 4.2.2.5.

Note :

( 1) T h e term inal settl ing vel oc ity of th e l atent p artic ul ate is estim ated as:

( )

w = 1.068 W h ere:

w = term inal settl ing vel oc ity of th e p artic l e ( m / s ( f t/ s) )

2 2 g = gravitational ac c el eration ( 9.81 m / s ( 32.2 f t/ s ) )

d = Diam eter of th e p artic l e ( 2.38 m m ( 0.094 inc h ) , th e p artic l e siz e is assum ed to b e th e sam e as th e p erf orated p l ate h ol e siz e of th e IRW ST sum p strainers )

3 3 s = m ass density of th e p artic l e ( 2.70 g/ c m ( 168.6 l b m / f t ) ) ( T ab l e 3.3-2) 3 3

= m ass density of th e f l uid ( 1.00 g/ c m ( 62.4 l b m / f t ) , density at 0°C ( 32°F) )

KEPCO & KHNP 95

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-5 Post-L OCA Fl uid Constituents Dow nstream of IRW ST Sum p Strainer Deb ris M ass Conc entration Deb ris T y p e Deb ris Q uantity Density

( k g/ lb ) (p p m )

3 3 3 1.51 g/ c m /

Q ual if ied ep ox y c oating 0.0878 m / 3.1 f t 3 132.2 / 291.4 148 94 l b / f t L atent p artic ul ates 83.9 k g / 185 l b - 83.9 / 185 94 L atent f ib er 6.8 k g / 15 l b - 6.8 / 15 8 T otal - - 222.9 / 491.4 250 KEPCO & KHNP 96

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-6 Af f ec ted Eq uip m ent/ Fl ow Rates ( 1 of 2)

Inner Diam eter Designed Assum ed Assum ed M ax im um Settl ing Com p onent

( inc h ) Fl ow Rate ( gp m ) Fl ow Rate ( gp m ) V el oc ity ( f t/ sec ) V el oc ity ( f t/ sec )

Orif ice CS-OR01A/ B 3.51 480 400 13.25 0.70 CS-FE338/ 348 9.045 480 400 1.99 0.70 CS-OR02A/ B 4.441 172 150 3.10 0.70 CS-OR03A/ B 5.129 169 150 2.33 0.70 CS-OR04A/ B 2.657 27 20 1.16 0.70 CS-OR05A/ B 1.323 24 20 4.66 0.70 CS-OR06A/ B 1.218 24 20 5.50 0.70 SI-OR01A/ B / C/ D 0.8 105 80 51.00 0.70 SI-OR06A/ B 1.594 105 80 12.85 0.70 SI-OR06C/ D 1.662 105 80 11.82 0.70 SI-OR07A/ B 1.65 105 80 11.99 0.70 SI-OR08A/ B / C/ D 0.491 105 80 135.39 0.70 SI-OR20A/ B / C/ D 1.153 105 80 24.55 0.70 SI-FE311D/ 321B / 331C/ 341A 2.126 105 80 7.22 0.70 SI-FE390C/ 391D 2.126 105 80 7.22 0.70 Containment Spray Noz z le M ain sp ray noz z l e 0.516 15.2 1.5 2.30 0.70 Aux il iary sp ray noz z l e 0.22 3 0.3 2.53 0.70 KEPCO & KHNP 97

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-6 Af f ec ted Eq uip m ent/ Fl ow Rates ( 2 of 2)

Inner Diam eter Designed Assum ed Assum ed M ax im um Settl ing Com p onent

( inc h ) Fl ow Rate ( gp m ) Fl ow Rate ( gp m ) V el oc ity ( f t/ sec ) V el oc ity ( f t/ sec )

Piping 18" CS p um p suc tion l ine ( SS Sc h . 80) 16.124 480 400 0.63 0.70 16" CS p um p suc tion l ine ( SS Sc h . 80) 14.312 480 400 0.80 0.70 14" CS p um p disc h arge l ine ( SS Sc h . 80) 12.5 480 400 1.04 0.70 12" CS p um p disc h arge l ine ( SS Sc h . 80S) 11.75 480 400 1.18 0.70 14" CS sp ray h eader l ine ( SS Sc h . ST D) 13.25 480 400 0.93 0.70 12" CS sp ray h eader l ine ( SS Sc h . 40S) 12 432 400 1.13 0.70 8" CS sp ray h eader l ine ( SS Sc h 40S) 7.981 172 150 0.96 0.70 6" CS sp ray ring l ine ( SS Sc h 40S) 6.065 106 80 0.89 0.70 4" CS sp ray ring l ine ( SS Sc h 40S) 4.026 27 20 0.50 0.70 4" CS p um p m inif l ow l ine ( SS Sc h 40) 4.026 480 400 10.07 0.70 10" SI IRW ST return l ine ( SS Sc h 120) 9.062 480 400 1.99 0.70 24" SI p um p suc tion l ine ( SS Sc h . 80) 21.562 585 480 0.42 0.70 20" SI p um p suc tion l ine ( SS Sc h . 80) 17.938 585 480 0.61 0.70 10" SI p um p suc tion l ine ( SS Sc h . 80S) 9.75 105 80 0.34 0.70 4" SI p um p disc h arge l ine ( SS Sc h . 120) 3.624 105 80 2.49 0.70 4" SI p um p m inif l ow l ine ( SS Sc h . 120) 3.624 105 80 2.49 0.70 4" SI p um p h ot l eg Inj ec tion l ine ( SS Sc h . 120) 3.624 105 80 2.49 0.70 4" SI p um p disc h arge l ine ( SS Sc h . 160) 3.438 105 80 2.76 0.70 12" SI p um p disc h arge l ine ( SS Sc h . 160) 10.126 105 80 0.32 0.70 KEPCO & KHNP 98

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-7 ECCS and CSS Com p onents W ear during 30 day s Design Assum ed Fl ow Assum ed Diam etric Fl ow Fl ow Rate Com p onent V el oc ity W ear Rate Rate -4 Inc rease

( f t/ sec ) ( x 10 , in)

( gp m ) ( gp m ) (% )

Orif ice CS-OR01A/ B 509 900 29.80 CS-FE338/ 348 5,991 7,200 35.91 TS CS-OR02A/ B 2,149 3,600 74.47 CS-OR03A/ B 2,111 3,600 55.83 CS-OR04A/ B 339 450 26.01 CS-OR05A/ B 304 450 104.89 CS-OR06A/ B 295 450 123.76 SI-OR01A/ B / C/ D 105 200 127.50 SI-OR06A/ B 1,130 1,600 256.92 SI-OR06C/ D 1,130 1,600 236.33 SI-OR07A/ B 1,130 1,600 239.78 SI-OR08A/ B / C/ D 105 200 338.48 SI-OR20A/ B / C/ D 105 200 61.38 SI-FE311D/ 321B / 331C/ 341A 1,130 1,600 144.43 SI-FE390C/ 391D 1,130 1,600 144.43 Containment Spray Noz z le M ain sp ray noz z l e 18 30 45.97 Aux il iary sp ray noz z l e 4 6 50.58 Piping 18" CS p um p suc tion l ine ( SS Sc h . 80) 6,500 7,200 14.34 16" CS p um p suc tion l ine ( SS Sc h . 80) 6,500 7,200 14.34 14" CS p um p disc h arge l ine ( SS Sc h . 80) 6,500 7,200 18.80 12" CS p um p disc h arge l ine ( SS Sc h . 80S) 6,500 7,200 21.28 14" CS sp ray h eader l ine ( SS Sc h . ST D) 5,991 7,200 16.73 12" CS sp ray h eader l ine ( SS Sc h . 40S) 5,392 7,200 20.40 8" CS sp ray h eader l ine ( SS Sc h 40S) 2,149 3,600 23.06 6" CS sp ray ring l ine ( SS Sc h 40S) 1,319 1,800 19.97 4" CS sp ray ring l ine ( SS Sc h 40S) 339 450 11.33 4" CS p um p m inif l ow l ine ( SS Sc h 40) 509 900 22.65 10" SI IRW ST return l ine ( SS Sc h 120) 6,500 7,200 35.77 24" SI p um p suc tion l ine ( SS Sc h . 80) 6,660 7,200 6.32 20" SI p um p suc tion l ine ( SS Sc h . 80) 6,660 7,200 9.13 10" SI p um p suc tion l ine ( SS Sc h . 80S) 1,235 1,600 6.87 4" SI p um p disc h arge l ine ( SS Sc h . 120) 1,235 1,600 49.71 4" SI p um p m inif l ow l ine ( SS Sc h . 120) 105 200 6.21 4" SI p um p h ot l eg Inj ec tion l ine ( SS Sc h .

1,130 1,600 49.71 120) 4" SI p um p disc h arge l ine ( SS Sc h . 160) 1,130 1,600 55.23 12" SI p um p disc h arge l ine ( SS Sc h . 160) 1,130 1,600 6.37 KEPCO & KHNP 99

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-8 W ear Rates of M aterial under Ab rasive Sl urries W ear Rates [ m m / y ear ( inc h es/ y ear) ]

M aterial Coarse Sand 2.13 m / sec ( 7 f t/ sec ) 4.58 m / sec ( 15 f t/ sec )

Steel 0.65 ( 0.0256) 1.81 ( 0.0713)

Al um inum 1.81 ( 0.0713) 7.48 ( 0.2945)

Pol y eth y l ene 0.06 ( 0.0024) 0.46 ( 0.0181)

AB S 0.36 ( 0.0142) 2.07 ( 0.0815)

Ac ry l ic 0.99 ( 0.0390) 4.10 ( 0.1614)

Geom etric Average 4.6183 KEPCO & KHNP 100

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.2-9 Pip ing and Assoc iated V al ves w ith L ow er Assum ed Fl ow V el oc ity th an Settl ing V el oc ity Pip ing Assoc iated val ves Desc rip tion Fl ow vel oc ity

( 1)

( f t/ sec )

4" CS sp ray ring l ine None 7.12 24" SI p um p suc tion None 5.84 l ine 20" SI p um p suc tion SI-V -304/ 305/ 308/ 309 Gate ( M OV ) , 20 inc h 8.44 l ine 10" SI p um p suc tion SI-V -130/ 131/ 402/ 470 Gate ( M anual ) , 10 inc h 5.30 l ine 12" SI p um p disc h arge SI-V -123/ 143/ 217/ 227/ 237/ Sw ing Ch ec k , 12 inc h 4.50 l ine 247/ 541/ 543 18" CS p um p suc tion SI-V -347/ 348 Gate( M OV ) , 18 inc h 8.51 l ine SI-V -157/ 158 Sw ing Ch ec k , 18 inc h Note:

( 1) T h e f l uid f l ow vel oc ity is b ased on th e ex p ec ted p um p op eration and m uc h h igh er th an th e term inal settl ing vel oc ity of 0.7 f t/ sec .

KEPCO & KHNP 101

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-1 ECCS Fl ow Rates p er FA Fol l ow ing a L OCA Core Fl ow APR1400 Fl ow Rate/

L OCA Sc enario ( 1) Rem ark Direc tion Fl ow Rate FA 18,700 L / m in 78 L / m in Hot-l eg l ine b reak U p w ard M ax im um f l ow rate of f our SI

( 4,940 gp m ) ( 20.5 gp m )

3,322 L / m in 14 L / m in Col d-l eg l ine b reak U p w ard B oil -of f f l ow rate at 700 sec onds

( 877.6 gp m ) ( 3.64 gp m )

Col d-l eg l ine b reak 9,350 L / m in 39 L / m in Dow nw ard M ax im um f l ow rate of tw o SI af ter HL SO ( 2,470 gp m ) ( 10.25 gp m )

Note :

( 1) 1/ 241 of m ax im um f l ow rate KEPCO & KHNP 102

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-2 B y p ass Deb ris T y p es and Am ounts p er FA

( 1)

Deb ris Generated Assum ed B y p ass Per FA Deb ris T y p e Sp ec if ic T y p e in Containm ent Deb ris ( k g) ( g)

NU KON 0 0 0 Fib rous 6.8 k g 1.67

( 2)

L atent f ib er 6.93

( 15 l b m ) ( 3.68 l b m )

Coating 280.5 k g 3 280.5 1,164 deb ris ( 3.1 f t )

Partic ul ate L atent 83.9 k g 348

( 185 l b m ) 83.9 p artic l e TS Ref l ec tive m etal insul ation 158.67 k g 658.3 Ch em ic al c om p ounds 158.67

( 349.8 l b m ) ( 59.8 l iters)

Note :

( 1) 1/ 241 of th e assum ed b y p ass deb ris am ount

( 2) Resul t of th e APR1400 strainer b y p ass testing KEPCO & KHNP 103

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-3 Inp uts f or Cal c ul ation of Hot-l eg dPavail V ariab l e Desc rip tion U nit V al ue Com m ents Z SG B ottom of th e SG tub esh eet m DC l iq uid density is Z c ore-in B ottom of ac tive f uel m sel ec ted at th e saturation 3

p ressure ( 3.312 k g/ c m 3 ( 47.113 p sia) , DCD T ab l e DC Dow nc om er ( DC) l iq uid density k g/ m 6.2.1-8 Part B , 599.9 sec ) .

Z RV CL RV noz z l e c enterl ine m TS KEPCO & KHNP 104

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-4 Inp uts f or Cal c ul ation of Col d-l eg dPavail V ariab l e Desc rip tion U nit V al ue Sourc e Z c ore-in B ottom of ac tive f uel m 3 DC l iq uid density is DC DC l iq uid density k g/ m sel ec ted at th e saturation p ressure 3

Z b rk Z RV Cl -Z IDCL /2 m ( 4.469 k g/ c m

( 63.57 p sia) , DCD T ab l e 6.2.1-7 Part Z RV CL RV noz z l e c enterl ine m B , 600.0 sec )

Z IDCL Inner diam eter of c ol d-l eg p ip e m TS KEPCO & KHNP 105

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-5 Inp uts f or Cal c ul ation of Col d-l eg af ter HL SO dPavail V ariab l e Desc rip tion U nit V al ue Com m ents Z so SG sp il l over el evation m DC l iq uid density is sel ec ted at th e Z c ore-out T op of ac tive f uel m saturation p ressure 3

DC l iq uid density k g/ m 3 ( 3.71 k g/ c m ( 52.769 DC p sia) , DCD T ab l e 6.2.1-Z RV CL RV noz z l e c enterl ine m 8 Part B , 3,996.9 sec )

TS KEPCO & KHNP 106

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-6 T im e Dep endent T em p erature Data T im e ( sec ) IRW ST T em p ( º F) CT M T T em p ( º F) RV Cool ant T em p ( º F) 3 120 213.5 586.1 17 121.4 265.8 374.4 40 126.7 262.8 307.4 114 137.8 266 302.4 121 138.3 266.3 302.1 301 151.1 274 296 600 169.1 271.2 296.9 700 173 269.9 295.9 701 173 269.9 295.9 900 178.7 267.5 294.1 1202 184.9 264.7 292.2 2409 203.4 258.5 287.8 3002 210.2 256.9 286.7 3606 215.9 255.5 285.5 5224 227.3 252.6 283.4 5225 227.3 252.6 283.1 9429 241 248.2 280 12002 244 246.5 278.9 14400 245.1 245.2 278 14401 245.1 245.2 278 28002 241.9 238.6 273.6 80002 221.4 218.6 261.3 100002 212.4 208.4 255.6 1000182 153.8 152.2 231.8 2600000 140.9 139.3 231.8 KEPCO & KHNP 107

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-7 Containm ent M aterial Inp ut Cl ass M aterial V al ue Al um inum sub m erged ( f t² ) 0.0 Al um inum sub m erged ( l b m ) 0.0 M etal l ic al um inum Al um inum not-sub m erged ( f t² ) 4,652 Al um inum not-sub m erged ( l b m ) 7,598 Cal c ium sil ic ate insul ation( f t³ ) 0 Asb estos insul ation ( f t³ ) 0 Cal c ium sil ic ate Kay l o insul ation ( f t³ ) 0 U nib estos insul ation ( f t³ ) 0 Fib ergl ass insul ation ( f t³ ) 12.5 NU KON ( f t³ ) 0 E-gl ass T em p -M at ( f t³ ) 0 T h erm al w rap ( f t³ ) 0 M ic roth erm ( f t³ ) 0 Sil ic a p ow der M in-K ( f t³ ) 0 M in-w ool ( f t³ ) 0 M ineral w ool Roc k w ool ( f t³ ) 0 Cerab l ank et ( f t³ ) 0 Fib erFrax durab l ank et ( f t³ ) 0 Kaow ool ( f t³ ) 0 Al um inum sil ic ate M at-c eram ic ( f t³ ) 0 M ineral f ib er ( f t³ ) 0 PAROC m ineral w ool ( f t³ ) 0 Conc rete Conc rete ( f t² ) 18,688 KEPCO & KHNP 108

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-8 Cool ant M aterial Inp uts Param eter U nit V al ue Note 3

g/ c m IRW ST w ater density M inim um l iq uid density

( l b m / f t³ )

3 M inim um IRW ST l evel f or SIS Initial IRW ST w ater vol um e m ( f t³ )

NPSH during L OCA rec irc ul ation M inim um IRW ST l evel f or SIS Initial IRW ST w ater m ass k g( lb m )

NPSH during L OCA rec irc ul ation 3

g/ c m Core region w ater Density M inim um l iq uid density

( l b m / f t³ )

Initial c ore region w ater 3 m ( f t³ ) OG-07-419 vol um e Initial c ore region w ater From m inim um l iq uid density and k g( lb m )

m ass initial c ore region w ater vol um e TS KEPCO & KHNP 109

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-9 Core M odel ing Param eters V al ue V ariab l e U nit W CAP-16793-NP APR1400 100% reac tor p ow er M W t 3,188 3,983 Crud th erm al c onduc tivity W / m -K 0.52 0.52 L OCA dep osit th erm al W / m -K 0.2 0.2 c onduc tivity Fuel rod OD Inc h es 0.36 0.374 Pel l et stac k l ength Inc h es 120 150 Average c l adding ox ide M ic rons 20 152 ( OG-07-419) th ic k ness Average starting c rud th ic k ness M ic rons 30 140 ( OG-07-419)

Num b er of regions ( 200 m ax ) 4 3 Num b er of ax ial nodes ( up and

( 10 m ax ) 3 3 dow n eac h region)

Distanc e f rom h ot-l eg inl et to Inc h es 47 39.748 top of p el l et stac k KEPCO & KHNP 110

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-10 Ax ial Nodal iz ation and Inp ut V al ues El evation Rel ative Pow er 1 ( T op ) 0.95 2 1.10 3( B ottom ) 0.95 KEPCO & KHNP 111

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-11 Radial Nodal iz ation and Inp ut V al ues Region Rel ative Pow er Num b er of Rods Perc entage of Rods 1 1.65 1 0.0018%

2 1.56 235 0.4132%

3 1.00 56,640 99.5851%

KEPCO & KHNP 112

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e 4.3-12 Sum m ary of Fuel Assem b l y T est Resul ts TS KEPCO & KHNP 113

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Boil-off flow WBO(t)

(gpm) 877.8 393.9 11.7 tmax (240) time(min)

Figure 4.3-1 Boil-of f Rate during 4 H ours KEPCO & KHNP 114

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Steam Generator Steam Generator Pressurizer Reactor Vessel Actual Driving ECCS force Water level Break Flow Core water Level Figure 4.3-2 Availab le Driving H ead at H ot-Leg Break Condition KEPCO & KHNP 115

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Steam Generator Steam Generator Pressurizer Reactor Vessel ECCS Steam Actual Downcomer Steam Driving Water level Break Flow force Core collapsed water level Figure 4.3-3 Availab le Driving H ead at Cold-Leg Break Condition KEPCO & KHNP 116

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Steam Generator Steam Generator Pressurizer Reactor Vessel Actual Driving force ECCS Water level Core water Level as Break Flow liquild Figure 4.3-4 Availab le Driving H ead at Cold-Leg Break af ter H LSO Condition KEPCO & KHNP 117

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 CleanSIBypass RecircBypass RecircLqFlow CleanSIFlow RVSteamFlow BOPBlowdown RVLqFlow SI Flow BreakFlow Spray Flow TSP Flow IRWST Debris Dissolution Figure 4.3-5 Flow Paths and Def initions f or LOCADM KEPCO & KHNP 118

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 4.3-6 M ax imum LOCA Scale T hick ness KEPCO & KHNP 119

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 4.3-7 Fuel Cladding T emperature KEPCO & KHNP 120

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 4.3-8 Pressure Drop (APR1400-21; P: F= 1: 1, 77.6 L/ min)

KEPCO & KHNP 121

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure 4.3-9 Pressure Drop (APR1400-95; P: F= 1: 50, 16.6 L/ min)

KEPCO & KHNP 122

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 5 CONCLUSION T h is tec h nic al rep ort p resents th at th e design and eval uation resul t of th e APR1400 IRW ST sum p strainer f ul l y sup p ort its saf ety f unc tion under p ost-ac c ident c onditions f ol l ow ing NRC RG 1.82, Rev.4, req uirem ents. T h e b reak sel ec tion, deb ris generation, c h arac teristic s, transp ort, and h ead l oss are eval uated c onsidering ap p rop riate c onservatism . U sing th ese data, c h em ic al ef f ec ts, up stream ef f ec t, and dow nstream ef f ec t as w el l as NPSH of th e ECCS and CSS p um p s are eval uated to verif y th at th ere is no signif ic ant im p ac t on ECCS and CSS p um p s, and rel ated sy stem s.

T h eref ore, th is rep ort c onc l udes th at th e APR1400 design f ul l y satisf ies NRC RG 1.82, Rev.4, req uirem ents and h as ap p rop riate design m argin to p erf orm saf ety f unc tions under p ost-L OCA c onditions.

KEPCO & KHNP 123

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 6 REFERENCES 1-1 Regul atory Guide 1.82, " W ater Sourc es f or L ong-term Rec irc ul ation Cool ing Fol l ow ing a L oss-of -

Cool ant Ac c ident," Revision 4, U .S. Nuc l ear Regul atory Com m ission, M arc h 2012.

1-2 SECY 0093, " Cl osure Op tions f or Generic Saf ety Issue-191, Assessm ent of Deb ris Ac c um ul ation on Pressuriz ed W ater Reac tor Sum p Perf orm anc e," U .S. Nuc l ear Regul atory Com m ission, J ul y 9, 2012.

2-1 Regul atory Guide 1.54 Revision 2, " Servic e L evel I, II, and III Protec tive Coatings Ap p l ied to Nuc l ear Pow er Pl ants," U .S. Nuc l ear Regul atory Com m ission, Oc tob er 2010.

2-2 AST M D 3911-08, " Standard T est M eth od f or Eval uating Coatings U sed in L igh t-W ater Nuc l ear" .

2-3 Revised Guidanc e f or Review of Final L ic ensee Resp onses to Generic L etter 2004-02," Potential Im p ac t of Deb ris B l oc k age on Em ergenc y Rec irc ul ation During Design B asis Ac c idents at Pressuriz ed-W ater Reac tors" , U .S. Nuc l ear Regul atory Com m ission, M arc h 2008 3-1 " Design Control Doc um ent f or th e APR1400," Rev.1, KEPCO & KHNP, M arc h 2017.

3-2 NEI 04-07, " Pressuriz ed W ater Reac tor Sum p Perf orm anc e Eval uation M eth odol ogy ," Nuc l ear Energy Institute, M ay 2004.

3-3 Saf ety Eval uation b y th e Of f ic e of Nuc l ear Reac tor Regul ation Rel ated to NRC Generic L etter 2004-02, Nuc l ear Energy Institute Guidanc e Rep ort ( Prop osed Doc um ent Num b er NEI 04-07) ,

" Pressuriz ed W ater Reac tor Sum p Perf orm anc e Eval uation M eth odol ogy ," Nuc l ear Energy Institute, Dec em b er 2004.

3-4 NRC Staf f Review Guidanc e regarding Generic L etter 2004-02, " Cl osure in th e Area of Strainer Head L oss and V ortex ing," U .S. Nuc l ear Regul atory Com m ission, M arc h 2008.

3-5 APR1400-E-A-T ( NR) -13002-NP, " APR1400 IRW ST ECCS Sum p Strainer Prototy p e Hy draul ic Q ual if ic ation T est Pl an," Rev. 1, KHNP, August 2013.

3-6 Regul atory Guide 1.1, Revision 4, " W ater Sourc es f or L ong-term Rec irc ul ation Cool ing Fol l ow ing a L oss-of -Cool ant Ac c ident," Revision 4, U .S. Nuc l ear Regul atory Com m ission, M arc h 2012.

3-7 APR1400-Z -A-NR-14007-P, " M ass and Energy Rel ease M eth odol ogies f or L OCA and M SL B ,"

Rev.1, KHNP, M arc h 2017.

3-8 EPRI, Advanc ed L igh t W ater Reac tor U til ity Req uirem ents Doc um ents V ol . II, AL W R EV OL U T IONARY PL ANT , Ch 5 " Engineered Saf ety Sy stem ," Rev.7, Dec em b er 1995.

3-9 CRANE, " Fl ow of Fl uids th rough V al ve, Fitting, and Pip e," T ec h nic al Pap er No. 410, 2009.

3-10 SECY 0014, " U se of Containm ent Ac c ident Pressure in Anal y z ing Em ergenc y Core Cool ing Sy stem and Containm ent Heat Rem oval Sy stem Pum p Perf orm anc e in Postul ated Ac c idents,"

U .S. Nuc l ear Regul atory Com m ission, J anuary 31, 2011.

3-11 W CAP-16530-NP-A, " Eval uation of p ost-Ac c ident Ch em ic al Ef f ec t in Containm ent Sum p Fl uid to Sup p ort GSI-191," Rev.0, W estingh ouse El ec tric Corp oration, Ap ril 2008.

3-12 ADS-Pip e T ec h nic al Note 2.116, " Ab rasion Resistanc e of Pip ing Sy stem s" , Hil l ard, Oh io 43026, Novem b er 1994.

4-1 APR1400-E-A-T ( NR) -13003-P, " APR1400 IRW ST ECCS Sum p Strainer B y p ass T est Pl an," Rev. 1, KHNP, August 2013.

4-2 NU REG/ CR-6808, " Know l edge B ase f or th e Ef f ec ts of Deb ris on Pressuriz ed W ater Reac tor Em ergenc y Core Cool ing Sum p Perf orm anc e," U .S. Nuc l ear Regul atory Com m ission, Feb ruary 2003.

4-3 W CAP-16406-P-A, " Eval uation of Dow nstream Sum p Deb ris Ef f ec ts in Sup p ort of GSI-191," Rev.

1, W estingh ouse El ec tric Corp oration, M arc h 2008.

4-4 NU REG/ CR-6902, " Ef f ec ts of Insul ation Deb ris on T h rottl e V al ve Fl ow Perf orm anc e," U .S.

Nuc l ear Regul atory Com m ission, M arc h 2006.

4-5 NU REG/ CR-6913, " Ch em ic al Ef f ec ts Head-L oss Researc h in Sup p ort of Generic Saf ety Issue 191, Argonne National L ab oratory ," U .S. Nuc l ear Regul atory Com m ission, 2006.

4-6 NU REG/ CR-6914, " Integrated Ch em ic al Ef f ec ts T est Proj ec t: Consol idated Data Rep ort, V ol um e 1," U .S. Nuc l ear Regul atory Com m ission, 2006.

4-7 W CAP-16793-NP, " Eval uation of L ong-T erm Cool ing Considering Partic ul ate, Fib rous and Ch em ic al Deb ris in th e Rec irc ul ating Fl uid," Revision 2, W estingh ouse El ec tric Corp oration, KEPCO & KHNP 124

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Oc tob er 2011.

4-8 " Final Saf ety Eval uation b y th e Of f ic e of Nuc l ear Reac tor Regul ation: T op ic al Rep ort W CAP-16793-NP, Revision 2," U .S. Nuc l ear Regul atory Com m ission, Ap ril 2013.

4-9 APR1400-F-A-NR-14003-P, Rev. 0, Post-L OCA L ong T erm Cool ing Eval uation M odel , KHNP, Sep tem b er 2014.

4-10 APR1400-K-A-NR-14001-P, Rev. 2, In-vessel Dow nstream Ef f ec t T ests f or th e APR1400, KHNP, Feb ruary 2017.

4-11 KHNP, APR1400-F-A-NR-14004-P, Rev. 0, Pressure Drop s T h rough a L oop Fol l ow ing L oss-of -

Cool ant Ac c idents, Dec em b er 2014.

4-12 PW ROG OG-07-419, T ransm ittal of L OCADM Sof tw are in Sup p ort of W CAP-16793-P, Eval uation of L ong-T erm Cool ing Assoc iated w ith Sum p Deb ris Ef f ec ts ( PA-SEE-0312) ,

Sep tem b er 2007.

4-13 PW ROG OG-07-534, T ransm ittal of Additional Guidanc e f or M odel ing Post L OCA Core Dep osition w ith L OCADM Doc um ent f or W CAP-16793-NP ( PA-SEE-0312) , Dec em b er 2007.

4-14 PW ROG OG-08-64, T ransm ittal of L T R-SEE-I-08-30, Additional Guidanc e f or L OCADM f or M odif ic ation to Al um inum Rel ease f or W estingh ouse T op ic al Rep ort W CAP-16793-NP ( PA-SEE-0312) , Feb ruary 2008.

KEPCO & KHNP 125

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Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1 General No response necessary - Introductory Material.

This section includes regulatory positions on design criteria, performance standards, and analysis methods that relate to all water-cooled reactor types (Section C.1.1) and to specific light-water reactor types (PWRs in Section C.2 and BWRs in Section C.3). As stated in the introduction to this guide, the purpose of the guidance is to identify information and methods that the NRC staff considers acceptable for use in evaluating analytical techniques and implementing regulations related to water sources for long-term cooling of both existing and future reactor systems.

1.1 Regulatory Positions Common to All Water-Cooled No response necessary - Introductory Material.

Reactors Research, analysis, and lessons learned have shown that similar approaches are appropriate for water-cooled reactors in a number of areas when the long-term recirculation capability evaluation is performed. These areas include net positive suction head (NPSH) evaluation, selection of limiting pipe breaks, debris generation, debris transport, coating debris, latent debris, sump structure, downstream effects, chemical effects, structural analyses, and head loss testing.

KEPCO & KHNP A3

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1 Emergency Core Cooling System Sumps, Suppression No response necessary - Introductory Material.

Pools, Suction Strainers, and Debris Interceptors The design features and capabilities that minimize the potential The emergency core cooling system (ECCS) sumps or for loss of water sources for long-term cooling are presented suppression pools, which are the source of water for functions below.

such as ECCS and containment heat removal following a loss of coolant accident (LOCA), should contain an appropriate combination of the features and capabilities listed below to ensure the availability of the water sources for long-term cooling.

KEPCO & KHNP A4

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.1 A minimum of two independent ECCS suction strainers should Conformance.

be provided, each with sufficient capacity to accommodate the Four separate, independent, and redundant trains of the safety full plant debris loading while providing sufficient flow to one injection system (SIS) and containment spray system (CSS) with train of the ECCS and containment heat removal pumps. To two safety injection (SI) pumps and one containment spray (CS) the extent practical, the redundant suction strainers should be pump in each division are provided. Within each division, the two physically separated from each other by structural barriers to SI trains (and each CS train) are separated by a quadrant wall to preclude damage resulting from a LOCA, such as whipping isolate the trains from each other to the maximum extent pipes or high-velocity jet impingement. practical. Each of the four SI pumps has its own suction connection to the in-containment refueling water storage tank (IRWST), and each of two CS pumps shares one of these four connections. Four sumps are provided in the IRWST. Each IRWST sump contains paired CSS/SCS and SI suction pipes (two sumps: SI and CS pump suction pipes, two sumps: SI and SC pump suction pipes). Each pair of CSS/shutdown cooling system (SCS) and SI suction pipes ends in a suction sump, with each suction sump installed adjacent to an associated strainer (four total). Four strainers and sumps are located inside the IRWST isolated compartment, which protect high-energy piping systems in containment. The IRWST is inside the vertical concrete of the reactor containment buildings. The IRWST is toroidal and arranged continuously around the lower containment. The bottom of the IRWST is formed by the upper concrete of the internal structure. The top is formed by the concrete slab. This provides for an enclosed structure. The strainers are installed away from the spargers to minimize the effect of hydrodynamic loads induced by the discharge of water, air, and single- and two-phase steam due to the opening of the pressurizer pilot-operated safety relief valves (POSRVs) into the IRWST.

KEPCO & KHNP A5

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.2 The containment floor in the vicinity of floor-mounted ECCS Not applicable strainers should slope gradually downward away from the The APR1400 design does not require that the floor in the vicinity strainers to retard floor debris transport and reduce the fraction of the IRWST sumps be sloped away from the sump for the of debris that might reach the suction strainer. Similar floor following reasons:

sloping should be used in the vicinity of a sump pit if the ECCS The trench is provided upstream of the trash racks facing each strainers are installed in a pit configuration. Debris interceptors opening in the shield wall to prevent high-density debris from or curbs can also be used to retard debris transport.

being swept along the floor into the holdup volume tank (HVT).

The vertical trash racks, located at the entrance to the HVT on El.

100-0, will intercept any debris entering the HVT. The IRWST, due to the location of the isolated compartment, is not subject to heavy debris loading.

The IRWST sump strainers have a significant surface area and the effect of debris will be minimal. All these features, coupled with the very low flow velocities in the IRWST, will significantly reduce the amount of debris that might reach the strainer.

1.1.1.3 The inlet of pumps required for long-term cooling should be Conformance.

protected by a suction strainer placed upstream of the pumps Each IRWST sump contains paired CSS/SCS and SI suction to prevent the ingestion of debris that may damage pipes (two sumps: SI and CS pump suction pipes, two sumps: SI components or block restrictions in the systems served by the and SC pump suction pipes). Each pair of CSS/SCS and SI pumps. suction pipes ends in a suction sump, with each suction sump installed adjacent to an associated strainer (total four strainers).

The strainers in the IRWST filter the finer debris (typically down to 2.34 mm (0.094 in) that is passed through the HVT trash rack plus any debris left in the IRWST from maintenance operations.

This provides more area to stop debris while allowing more than adequate flow for the safety system.

KEPCO & KHNP A6

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.4 All drains from the upper regions of the containment should Conformance.

terminate in such a manner that direct streams of water will not The IRWST sumps are located inside the IRWST compartment directly impinge on, or discharge in close proximity to, the where drains do not directly impinge on them. The drain piping ECCS strainers. Streams of drainage from upper containment empties into the containment drain sump. There are no drains or may contain entrained debris and could also result in air narrow pathways directly to the IRWST. Floor drain piping that ingestion and other issues if they directly impinge on the collects in the containment sump, such as the compartment floor strainers. The drains, drain piping internal clearances, and and operating floor, is assumed to become blocked.

other pathways that connect containment compartments with CS water is drained to lower containment levels by stairway potential break locations to the sump or suppression pool openings, equipment hatch, or compartment access openings.

should be designed to ensure that they would not become These openings are not considered to be narrow pathways blocked by the debris; this will ensure that water needed for an vulnerable to blockage. Since the floor drains are assumed to be adequate NPSH margin could not be held up or diverted from blocked, an amount of CS water is assumed to collect and the pool.

remain on various containment levels. The heights of the water remaining on the containment floors are assumed to be 5.08 cm (2 in) on the floors above El. 114-0, 30.48 cm (12 in) on the refueling cavity, 11.11 cm (4.375 in) in the annulus area, and 31.32 cm (12.332 in) in the secondary shield wall on the El. 100-0 floor. This amount of remaining water is factored into the return water holdup volume in the calculation of IRWST water levels.

KEPCO & KHNP A7

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.5 Trash racks, suction strainers, and debris interceptors should Conformance.

be capable of withstanding the loads imposed by expanding A vertical trash rack is located at each entrance to the HVT. Two jets, missiles, the accumulation of debris, and pressure trash racks are located in the side wall of the HVT within the differentials caused by post-LOCA blockage under design- secondary shield wall. Two trash racks are located facing the basis or realistic flow conditions, whichever causes the greater opening in the secondary shell wall from the annulus. The trash loads. When evaluating the impacts from potential expanding racks are designed to seismic Category I and provide distance for jets and missiles, licensees should justify credit for any protection from jet impingement and missiles. The strainers and protection offered by surrounding structures or credit for sumps are located inside the IRWST compartment. The IRWST remoteness of trash racks and strainers from potential high- is protected by concrete walls and structures, so the strainer will energy sources. not be exposed to missiles. Strainers are designed to seismic Category I. The structural analysis of the strainer includes static loads imposed by maximum flow with the debris in place and hydrodynamic loads from a seismic event.

1.1.1.6 ECCS strainers, trash racks, and debris interceptors should be Conformance.

designed to withstand the inertial and hydrodynamic effects The strainer design basis includes seismic and hydrodynamic caused by the vibratory motion of a safe-shutdown earthquake loads caused by design basis safe shutdown earthquake (SSE).

following a LOCA without loss of structural integrity.

1.1.1.7 Licensees should select materials for debris interceptors, trash Conformance.

racks, and suction strainers that do not degrade during periods The strainers are made of stainless steel materials that resist of inactivity or operation and that have a low sensitivity to degradation during inactive periods and resist degradation in the stress-assisted corrosion or general corrosion that may be chemically reactive post-LOCA environment.

induced by chemically reactive spray or by the containment or suppression pool liquid during a LOCA.

KEPCO & KHNP A8

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.8 Licensees should choose a suction strainer design (i.e., size Conformance.

and shape) that will prevent unacceptable loss of NPSH The IRWST sump strainers are designed so that NPSH is not lost margin from debris accumulation during the period that the even with maximum debris loading due to their large surface ECCS and CSS are required to operate in order to maintain area, which provides ample filtration area. An active strainer long-term cooling or to maximize the time before the loss of blockage mitigation system is not applicable to the APR1400.

NPSH caused by debris blockage when used with an active mitigation system (see Section C.1.1.4).

1.1.1.9 Licensees should assess the possibility of debris clogging Conformance.

narrow flow passages downstream of the ECCS strainer to The debris strainers are made of stainless steel and could use ensure adequate long-term recirculation cooling, containment perforated plate with a 2.38 mm (0.094 in) diameter hole. The cooling, and containment pressure control capabilities. The APR1400 design has been evaluated for strainer downstream size of the openings in the strainer should be determined by effects. All downstream components are capable of fulfilling their considering the flow restrictions of systems served by the design basis functions for the required duration the post-LOCA.

containment pool. Licensees should consider the potential for long, thin slivers passing axially through the suction strainer and then reorienting and clogging at any flow restriction downstream.

KEPCO & KHNP A9

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.10 Licensees should consider the buildup of debris and chemical Conformance.

reaction products at downstream locations, including The WCAP-16406-P methodology and its associated acceptance containment spray nozzle openings, HPSI throttle valves, criteria were used to evaluate APR1400 downstream ECCS and coolant channel openings in the core fuel assemblies, fuel CSS components. The effects of debris ingested through the assembly inlet debris screens, ECCS pump seals, bearings, containment sump strainer during the recirculation mode of the and impeller running clearances. The design of the ECCS ECCS and CSS include erosive wear, abrasion, and potential pumps is a large factor in determining the sensitivity of the blockage of flow paths. The smallest clearance found for heat pump operability to ingestion of debris. Three aspects of pump exchangers, orifices, and spray nozzles in the recirculation flow operability hydraulic performance, mechanical shaft seal path is 9.271 mm (0.365 in) for orifices on the SI pump discharge assembly performance, and pump mechanical performance flow path; therefore, no blockage of the ECCS flow path is (vibration)must be considered when evaluating the ECCS expected with an IRWST sump strainer with a hole size of 2.38 pumps for operation with debris-laden water. Westinghouse mm (0.094 in). The instrumentation tubing is also evaluated for Commercial Atomic Power (WCAP)-16406-P-A, Evaluation of potential blockage of the sensing lines. The transverse velocity Downstream Sump Debris Effects in Support of GSI-191 5 past this tubing is sufficient to prevent debris settlement into (Reference 21), and its SE (Reference 22) provide evaluation these lines, so no blockage will occur. The heat exchangers, methods and criteria that the NRC considers acceptable. If orifices, and spray nozzles were evaluated for the effects of wear or internal blockage evaluations indicate that a erosive wear over the mission time of 30 days. The erosive wear component may not be able to accomplish its design function on these components is determined to be insufficient to affect throughout its mission time and that it is not practical to install system performance. For pumps, the effect of debris ingestion a suction strainer with openings small enough to filter out through the IRWST sump strainer on three aspects of operability, debris that cause excessive damage to ECCS pump seals or including hydraulic performance, mechanical shaft seal assembly bearings, the NRC expects licensees to modify the ECCS performance, and mechanical performance (vibration) of the pumps or procure new ECCS pumps that can operate long pump, were evaluated. The hydraulic and mechanical term under the postulated conditions. WCAP-16793-NP, performance of the pump was determined to be unaffected by the Revision 2, Evaluation of Long-Term Cooling Considering recirculating debris.

Particulate, Fibrous, and Chemical Debris in the Recirculating Fluid, issued October 2011 (Reference 23), discusses a method for use in evaluating the downstream impact of debris on the fuel assemblies, KEPCO & KHNP A10

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.10 as discussed further in Section C.1.3.8.b of this guide. (At the A LOCADM calculation is performed to assess the in-vessel (cont.) time this guide was revised, the NRC staff had not yet downstream effect on the APR1400, applying the evaluation completed its review of WCAP-16793-NP). WCAP-16530-NP- methods and acceptance bases provided in WCAP-16793-NP, A, Evaluation of Post-Accident Chemical Effects in Revision 2.

Containment Sump Fluids To Support GSI- 191, issued March An analysis was performed to determine the type and quantity of 2008 (Reference 24), provides a general approach to chemical precipitates that may form in the post-LOCA conducting chemical effects evaluations, as discussed in recirculation fluid for the APR1400 design. The analysis Section C.1.3.10 of this guide. evaluated these post-LOCA chemical effects using the methodology developed in WCAP-16530-NP-A.

1.1.1.11 ECCS strainers and suction inlets for pumps required for long- Conformance.

term ECCS, CSS, or suppression pool cooling functions should During a LOCA, the minimum depth of water in the IRWST be designed to prevent degradation of pump performance is1.52 m (5 ft). At that minimum depth, the top of each strainer is through air ingestion, flashing, and other adverse hydraulic submerged 0.61 m (2 ft) below the surface of the IRWST water.

effects (e.g., circulatory flow patterns, high-intake head losses, The minimum water level is sufficient to preclude adverse gas void intrusion). hydraulic effects (e.g., vortex formation and high suction head loss). A low approach velocity at the strainer surface also mitigates the risk of a vortex.

1.1.1.12 Advanced strainer designs have demonstrated capabilities that Conformance.

are not provided by simple flat plate or basket type strainers or Advanced strainer designs have demonstrated capabilities that screens. The performance characteristics and effectiveness of are not provided by simple flat plate or basket type strainers or such designs should be supported by appropriate test data for screens. The performance characteristics and effectiveness of any particular intended application. such designs should be supported by appropriate test data for any particular intended application. Under the APR1400 design attributes, the IRWST sump strainers are verified by testing for head loss or chemical effects.

KEPCO & KHNP A11

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.1.13 Prototypical head loss testing should be done to verify suction Not applicable.

strainer designs. Section C.1.3.12 provides guidance on Prototypical head loss testing is done to verify suction strainer prototypical head loss testing. designs. Section C.1.3.12 provides guidance on prototypical head loss testing.

1.1.2 Minimizing Debris The design features and capabilities employed to minimize debris The debris and chemical reaction products (see Sections are presented below.

C.1.3.3 and C.1.3.10) that could accumulate on the suction strainer should be minimized.

1.1.2.1 Licensees should maintain debris source terms to less than the To be addressed by the combined license (COL) applicant.

amount assumed in the strainer performance analysis. For Performance of the strainers is enhanced by cleanliness example, cleanliness programs should ensure that the programs that limit debris in the containment. A COL applicant assumed latent debris and suppression pool sludge loading is that references the APR1400 design certification is to describe not exceeded, and controls should be maintained to ensure the containment cleanliness program that limits debris in that problematic debris (e.g., insulations, signage, coatings, containment.

foreign materials, and chemically reactive materials) are not introduced into containment to an extent that would exceed the analytically assumed values. In addition, permanent plant changes inside containment should be programmatically controlled so as to not change the analytical assumptions and numerical inputs of the licensee analyses.

KEPCO & KHNP A12

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.2.2 When latent debris is a significant source of debris (i.e., latent To be addressed by the COL applicant.

debris contributes more than a minimal amount to strainer As noted in Item 1.1.2.1, this is to be developed by the COL head loss) that can affect strainer performance or create applicant. The program will be established for control a downstream effects, periodic containment surveys or sampling permanent and temporary modifications to ensure that potential should be performed to verify that the amount of latent debris quantities of post-accident debris are maintained within the is within the assumed limits. Such periodic monitoring may not bounds of the analyses and design bases that support ECC and be necessary if the latent debris evaluation incorporates CS recirculation functions and ensure the long term core cooling sufficient conservatism to account for the substantial requirements of 10 CRF 50.46. The program will also be uncertainties associated with latent debris sampling (See established for control the foreign material exclusion to limit the section 1.3.6 for more information regarding latent debris). introduction of foreign material and debris sources into containment.

1.1.2.3 Licensees should adequately assess any new or unanalyzed To be addressed by the COL applicant.

potential debris sources (e.g., fiber and coatings) resulting from The APR1400 does not define specific type of materials for future equipment modifications inside containment against miscellaneous debris, such as tapes, tags or stickers, because assumptions of debris quantities and types inside containment, these are controlled by foreign material control program as specified in the post-accident sump/pool analysis. established by plant owner. To deal with this uncertainty, a 9.29 2 2 Additionally, licensees should assess tags and labels, which m (100 ft ) penalty of sacrificial strainer surface area per sump is applied as a margin for future detail design and installation of the can fail and be transported to the strainer, and determine a APR1400.

sacrificial strainer area to account for the strainer area that could become fully blocked by these transportable tags, labels, and other miscellaneous debris.

KEPCO & KHNP A13

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.2.4 Licensees should consider using insulation types (e.g., Not applicable.

reflective metallic insulation) that transport less readily and (This item applies to potential insulation replacement after the cause less severe head losses once deposited onto the plant is licensed and is operating) strainer in place of insulation types (e.g., fibrous and The APR1400 design uses reflective metal insulation (RMI) for microporous) that can become debris which can more readily piping and components inside containment. Use of fibrous or transport to the strainer and cause higher head losses. If particulate insulation could adversely affect sump strainer insulation is replaced or otherwise removed during performance and is limited to the greatest extent practicable.

maintenance, abatement procedures should be established to Programmatic controls will be in place to verify containment avoid generating latent debris in the containment.

cleanliness and provide reasonable assurance that no problematic material is present in the containment.

1.1.2.5 To minimize potential debris caused by the chemical reaction Conformance.

of the pool water with metals in the containment, licensees Trisodium phosphate (TSP) is used as a buffering agent, and the should reduce as much as practical the exposure of bare metal use of the aluminum is minimized to preclude adverse chemical surfaces (e.g., aluminum and uncoated carbon steel) to effects.

containment cooling water through spray impingement or As part of the evaluation of IRWST strainer performance for the immersion either by removal or by chemical-resistant APR1400, a chemical effects evaluation was conducted to protection (e.g., qualified coatings or jacketing).

identify specific compounds and quantities of materials that may precipitate within IRWST sump following a LOCA. An analysis was performed to determine the type and quantity of chemical precipitates that may form in the post-LOCA recirculation fluid for the APR1400 design. The analysis evaluated these post-LOCA chemical effects using the methodology developed in WCAP-16530-NP-A.

KEPCO & KHNP A14

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1.1.3 Instrumentation and Operator Actions Not applicable.

If a licensee relies on operator actions to mitigate the The APR1400 does not rely on operator action as the primary consequences of the accumulation of debris on the ECCS mitigation strategy. CS pump and SI pump operating information suction strainer, it should ensure that safety-related is available in the main control room (MCR) to assist in an NPSH instrumentation that provides operators with an indication and evaluation, which includes flow, suction, and discharge pressure.

audible warning of impending loss of NPSH for ECCS pumps is available in the control room. If a licensee relies on operator actions to prevent the accumulation of debris on ECCS suction strainers or to mitigate the consequences of the accumulation of debris on the ECCS strainers, it should evaluate whether the operator has adequate indications, training, time, procedural guidance, and system capabilities to perform the necessary actions.

1.1.4 Active Systems Not applicable.

An active device or system may be provided to prevent An active strainer blockage mitigation system is not applicable to excessive accumulation of debris on the ECCS strainers or to the APR1400.

mitigate the consequences of debris accumulation on the strainers. An active system should be able to prevent the accumulation and entry into the system of debris that may block restrictions found in the systems served by the ECCS pumps. The operation of the active component or system should not adversely affect the operation of other ECCS components or systems. In some operational modes, an active system may allow more debris to pass through the strainer. If this is the case, then the downstream effects analysis should be performed accordingly. Performance characteristics of an active system should be supported by appropriate test data that address head loss performance. Active systems should meet the requirements for redundancy for active components.

KEPCO & KHNP A15

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.1.5 Inspection Conformance.

To ensure the operability and structural integrity of the ECCS Personnel hatches are provided on top of the IRWST for access strainers and associated structures, access openings may be to the IRWST and strainers include openings to allow inspection, necessary to permit inspection of the ECCS strainers and so that structural integrity can be confirmed. Access into the associated structures, sump pits, and pump suction piping sump allows inspection of piping ends and evidence of structural inlets. On a regular basis, licensees should inspect (including distress or abnormal corrosion of strainers can be detected. The visual examination) strainers, trash racks, vortex suppressors, sump and strainer are inspected as part of the containment and pump suction piping inlets for evidence of structural closeout process to minimize the potential for operation with an degradation, potential for debris bypass, and presence of unacceptable configuration. In-service inspection of strainers is corrosion or debris blockage. The licensee should conduct addressed in the Technical Specification surveillance 3.5.2.

similar inspections for drainage flowpaths (e.g., refueling cavity drains, floor drains), debris interceptors, trash racks, and other design features upstream of the ECCS strainers that are credited in the strainer performance analysis. Inspection of the ECCS strainer, associated structures, and upstream components is best conducted late in a refueling outage to ensure the absence of debris generated by construction or maintenance in the vicinity of the ECCS strainers and upstream design features.

KEPCO & KHNP A16

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.2 Evaluation of Alternative Water Sources Not applicable.

Licensees should establish emergency operating procedures The APR1400 design does not require an alternate source of to use alternative water sources, either safety-related or non- water. As described in Item 1.1.3, operator actions are not relied safety-related, that will be activated if unacceptable head loss upon to mitigate the consequences of debris accumulation. The renders the ECCS strainers inoperable. For some plant strainer is adequately sized to provide reasonable assurance that designs, the use of alternative water sources may involve the available NPSH is sufficient.

replenishing the inventory of the water storage tank that served as the source of inventory for core cooling during the injection phase of the LOCA. In this case, if the flow rate of the makeup supply to the alternative water source is not larger than the core boiloff rate, procedures should direct replenishment of the water storage tank with alternative water sources following the switchover to recirculation. This flowpath should have a sufficient flow rate to ensure that an adequate water supply will be available in the water storage tank if excessive debris blockage subsequently renders the ECCS strainers inoperable.

Licensees should periodically inspect and maintain the valves needed to align the ECCS, CSS, and suppression pool cooling pumps from the recirculation water source to an alternative water source. The impact of adding water volume to containment should be evaluated, if this step is to be used.

KEPCO & KHNP A17

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3 Evaluation of Long-Term Recirculation Capability Conformance.

a. To demonstrate that a combination of design features and operator actions are adequate to ensure long-term cooling and that the criteria of 10 CFR 50.46(b)(5) will be met following a LOCA, licensees should evaluate the long-term recirculation capability. The techniques, assumptions, and guidance described below should be used in a plant-specific evaluation to ensure that any implementation of a combination of the features and capabilities listed in Section C.1.1 are adequate to ensure the availability of a reliable water source for long-term recirculation following a LOCA.

These assumptions and guidance can also be used to develop conditions for the suction strainer testing.

KEPCO & KHNP A18

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3 b. Licensees should evaluate (1) ECCS strainer hydraulic As part of the GSI resolution for the APR1400 design, IRWST (cont.) performance (e.g., geometric effects, air ingestion, flashing, sump performance was evaluated in accordance with NRC RG gas void accumulation), (2) debris effects (e.g., break 1.82 requirements. Vortexing, air injection, flashing, and selection, debris generation, debris transport, latent debris, deaeration were assessed to address adverse hydraulic effects.

chemical precipitation, upstream, downstream, interceptor The break selection, debris generation, and debris transport were blockage, strainer head loss, and structural integrity), and analyzed to identify the potential debris that may reach the (3) the combined impact on NPSH available at the pump strainers in the IRWST assuming a number of conservative inlet to confirm and ensure that long-term recirculation considerations. The characteristics of potential debris are set, cooling can be accomplished following a LOCA. Such an identified, and referred appropriately, and used in the NPSH evaluation should demonstrate adequate strainer and evaluation of SI, CS, and SC pumps, as well as in the design pumping performance (e.g., adequate pump NPSH values for purchase specification of IRWST sump strainers. The margins, adequate strainer structural strength, and no upstream effect used to identify the flowpaths that could result in excessive air ingestion). Licensees should also assess the blocking the return water, which could challenge the IRWST susceptibility to debris blockage of the containment minimum water level evaluation, was evaluated and the drainage flowpaths to the recirculation sump or suppression downstream effects of debris flow through the strainers were also pool. A holdup of water to the pool could affect the NPSH evaluated.

available, flashing and/or air ingestion evaluations. In As a result of the evaluation, it was verified that the APR1400 addition, licensees should assess the structural adequacy design does not challenge long-term recirculation capability in the of any interceptors or trash racks used to prevent debris event of a postulated LOCA.

blockage of these flowpaths to protect against a reduction in available NPSH if substantial amounts of water are held up or diverted away from the sump or suppression pool. A susceptibility assessment should also be made of the flowpaths and components downstream of the strainers to failure from debris blockage, particulate ingestion, and abrasive effects to protect against long-term degradation.

KEPCO & KHNP A19

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.1.1 The design of the emergency core cooling and containment Conformance with exception.

heat removal systems should ensure that sufficient available The APR1400 design does not fully conform to Section 1.3.1.1.

NPSH is provided to the system pumps, assuming the Credit was taken for containment accident pressure in maximum expected temperature of the pumped fluid and no determining available NPSH of SI pumps and SC/CS pumps of increase in containment pressure from that present before the the APR1400. The containment pressure is assumed to be equal postulated LOCA. to the initial containment pressure prior to the start of the

a. It is conservative to assume that the containment pressure accident. This fulfills the requirements of RG 1.1 and RG 1.82 equals the vapor pressure of the pool water. This ensures that the NPSH available is evaluated without crediting any that credit is not taken for containment pressurization during increase in pressure resulting from accident conditions at low the transient. temperatures less than 100 °C (212 ºF). This approach verifies

b. For PWR subatmospheric containments, this guidance that sufficient containment pressure is available under accident should apply after termination of the injection phase. For conditions. For temperatures higher than the initial saturation these subatmospheric containments, before termination of pressure, containment pressure was assumed to be equal to the the injection phase, NPSH analyses should include sump fluid vapor pressure. The NPSH margin calculation was conservative predictions of the containment atmospheric conducted to verify that NPSH available margin exists.

pressure and sump water temperature as a function of time.

1.3.1.2 For certain operating reactors in which it is not practicable to Not applicable.

alter the design, conformance with Section C 1.3.1.1 may not As described in Item 1.3.1.1, credit was taken for containment be possible. In these cases, the determination of available accident pressure in determining available NPSH.

NPSH should not include containment pressure above that which is necessary to preclude pump cavitation. The calculation of available containment pressure and sump/pool water temperature as a function of time should underestimate the expected containment pressures and overestimate the sump/pool water temperatures when determining available NPSH for this situation.

KEPCO & KHNP A20

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.1.3 If credit is taken for operation of an ECCS or containment heat Not applicable.

removal pump in cavitation, licensees should conduct As described in Item 1.3.1.1, the SI pumps and SC/CS pumps prototypical pump tests along with a posttest examination of are designed with sufficient NPSH margin to preclude pump the pump to demonstrate that pump performance will not be cavitation.

degraded and that the pump continues to meet all of the performance criteria assumed in the safety analyses. The time period in the safety analyses during which the pump may be assumed to operate while cavitating should not be longer than the time period for which the performance tests demonstrate that the pump meets the performance criteria.

1.3.1.4 Because high water temperatures reduce available NPSH and Conformance.

can affect the potential for flashing and impacts fluid properties, The containment post-LOCA pressure and IRWST temperature such as density and viscosity, the determination of the water profiles were used in NPSH calculation. The calculation for temperature should include the decay and residual heat IRWST water temperature includes decay heat with margin and produced following accident initiation. This calculation should all residual heat sources.

include the uncertainty in the determination of the decay heat (uncertainty in decay heat is typically included at the 2-sigma level). The licensee should calculate the residual heat with margin.

1.3.1.5 The correction factor for pumping high-temperature fluid Conformance.

discussed in ANSI/HI 1.3-2009 (Reference 5) to determine the The assessment of available NPSH for the SI pumps and CS margin between the available and required NPSH for the pumps of the APR1400 conservatively does not use the hot fluid ECCS and the containment heat removal systems should not correction factor specified in ANSI/HI 1.3-2009 to allow for be used. reduction in NPSH required.

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1.3.1.6 The calculation of available NPSH should take into account the Conformance.

minimum calculated height of water above the pump suction The minimum water level in the IRWST during post-LOCA is 26.2 and strainer surfaces. The calculated height of water should m (86.0 ft) (1.52 m (5 ft) above the IRWST bottom floor at not consider quantities of water that do not contribute to the elevation 81-0). The minimum post-LOCA water level in the sump or suppression pool (e.g., atmospheric steam, pooled IRWST was used in evaluation of available NPSH for SI pumps water on floors and in refueling canals, spray droplets and and SC/CS pump. The evaluation of minimum water level other falling water, holdup in containment coolers, water held includes identifying the holdup volumes, such as water volume up by upstream obstructions, and the volume of empty system lost to the containment atmosphere and on containment wall piping). Licensees should not credit non-leaktight structures, surfaces, piping fill volume, flooded volume of all compartments such as ducting for heating, ventilation, and air conditioning, for in the containment at an elevation lower than the main spillways, the displacement of water for the purposes of determining the spray volume, and other water volumes that could affect the flood minimum water level. The calculated height of water available height.

should not include the amount of water in enclosed areas that cannot readily be returned to the sump or suppression pool.

Minimum water level calculations should consider worst-case break locations (e.g., breaks at high elevations) that could lead to a minimum quantity of reactor coolant reaching the sump or suppression pool. Licensees should consider volume shrinkage of the reactor coolant inventory as it cools in terms of crediting the contribution of spilled coolant to the sump or suppression pool and in terms of the volume reduction of the coolant remaining in the primary system that will allow the ECCS to inject additional inventory into the primary system before filling it. Licensees should explicitly consider the limiting small-break LOCA water level because elevated break locations may be possible and certain sources of inventory (e.g., PWR accumulators) may not inject.

KEPCO & KHNP A22

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.1.7 Licensees should calculate the pipe and fitting resistance and Conformance.

the nominal strainer resistance without blockage by debris in a The calculation of hydraulic resistance of piping, fittings, and recognized, defensible method or determine it from applicable valves was performed using a conservative value from Crane experimental data. The clean strainer head loss (i.e., the Technical Paper 410. The clean strainer head loss was friction head loss caused by the passage of flow through the performed using widely recognized and approved industry strainer and any associated connecting pipes and plenums) standards.

calculations should consider the distribution of flow through the strainer that produces the highest head loss. For some curvilinear-type strainer designs, this occurs with a filtering debris bed near the strainer outlet and a clean strainer where the unobstructed flowpath is longer. If the strainer were partially covered with a filtering debris bed, much of the strainer flow could occur through the unblocked strainer surfaces, which could be more limiting for some designs.

1.3.1.8 Licensees should use Sections C 1.3.10 and C 1.3.11 to Conformance.

determine strainer head loss caused by blockage from LOCA- The strainer head loss use a conservative of 0.61 m-water (2 ft-generated debris and its chemical reaction products or from water) over the temperature of interest. The actual debris head foreign material in the containment that is transported to the loss is evaluated by qualified test results conducted specific to suction intake screens. the APR1400 plant conditions. Based on the results of strainer 2 2 testing, the maximum head loss for the 46.45 m (500 ft )

effective strainer area with the maximum debris load is 24.69 cm-water (0.81 ft-water) at the design flow rate and includes a clean screen component of 15.85 cm-water (0.52 ft-water). The strainer testing head loss of approximately 41% of the design strainer head loss of 60.96 cm-water (2.0 ft-water) ensures adequate NPSH margin for the ECCS pumps.

KEPCO & KHNP A23

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.1.9 Licensees should calculate available NPSH as a function of Conformance.

time until it is clear that the available NPSH will not decrease The NPSH margin calculation as a function of time was further. performed to provide reasonable assurance that NPSH available margin exists.

KEPCO & KHNP A24

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.2 Pipe Break Characterization Conformance.

a. A sufficient number of high-energy pipe break locations The methodology described in NEI 04-07 and the NRC Safety resulting in ECCS recirculation should be considered to Evalution Report (SER) for NEI 04-07 was used to assess pipe reasonably bound variations in debris generation by the break characterization. The following general break locations are size, quantity, and type of debris. The objective of the break considered:

selection process is to identify the break location and size Break Type No. 1: Break in the reactor coolant system that results in debris generation that produces the (RCS) with the largest potential for debris maximum head loss across the sump screen. Licensees Break Type No. 2: Largest break with two or more different should consider all aspects of the accident scenario for types of debris each postulated break location, including debris generation, Break Type No. 3: Break in the most direct path to the sump debris transport, latent debris, coating debris, chemical Break Type No. 4 : Large break with the largest potential effects, upstream and downstream effects of debris accumulation, and sump screen head loss. particulate debris to insulation ratio by weight Break Type No. 5 : Break that generates thin bed-high

b. The objective of strainer head loss testing is to simulate the particulate with low fiber debris from the break location that transports the maximum amount of debris to the sump strainer or the combination of The debris generated by the most limiting cases in Break No. 1 debris types that produces the maximum head loss. At a bounds Break Nos. 2 and 4 because the only type of insulation minimum, licensees should consider the postulated break used for the piping and equipment in containment is RMI. There locations and pipe break characteristics described in the are no breaks of a high-energy line within the IRWST, and Break following sections. No. 3 is not evaluated. Therefore, Break Nos. 1 and 5 are applicable.

c. Section 3.3.3 to 3.3.5 of NEI 04-07 (Reference 26) and the associated SE (Reference 27) and Section 3.2.1.1 of The junction of the RCS hot leg pipe (106.7 cm (42 in)) and the Reference 15 provide additional guidance in break selection steam generator was selected as the postulated limiting break KEPCO & KHNP A25

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.2 location. Destruction of insulation and coatings conservatively (cont.) used a zone of influence (ZOI) from a 106.7 cm (42 in) hot leg break. As noted in Item 1.3.2.2, the D-ring with the largest debris generation source is used. Further evaluation is addressed in the sump design technical report.

1.3.2.1 Licensees should consider breaks where debris is most easily Conformance.

transported to the suction strainer (e.g., breaks in areas with See response to Item 1.3.2.

the most direct path to the sump strainer or suppression pool).

1.3.2.2 Licensees should consider a spectrum of breaks, including the Conformance.

breaks with the largest quantity and greatest variety of debris See response to Item 1.3.2 within the expected zone of influence (ZOI).

1.3.2.3 Licensees should consider medium and large breaks that have Conformance.

the greatest potential ratio of particulate to fibrous insulation The performance of the IRWST sump strainers is based upon debris by weight and breaks that generate an amount of strainer validation testing. Four types of debris were used in the fibrous debris that, after its transport to the strainer, could form test. Aged Nukon fiberglass prepared as fines to simulate latent a thin layer that could subsequently filter sufficient particulate fiber, silicon carbide to simulate epoxy paint, sand mixture to debris to create a relatively high head loss (called the thin-bed simulate latent particulate, and aluminum oxy-hydroxide to effect). A thin bed is a relatively thin layer of debris on a simulate chemical debris The IRWST sump strainer testing has screen or strainer that causes a large flow resistance and, shown a thin bed developed on the strainer.

consequently, a large pressure drop for flowing liquid.

1.3.2.4 Licensees should disregard break exclusion zones in their Conformance.

evaluations (i.e., pipe breaks must be postulated in break The break exclusion zone was not considered in the APR1400 exclusion zones). design in accordance with the general guidance of NEI 04-07.

KEPCO & KHNP A26

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.2.5 Licensees should exclude NRC Branch Technical Position Conformance.

(BTP) 3-4, Postulated Rupture Locations in Fluid System The APR1400 design did not use BTP 3-4 as a basis for Piping inside and outside Containment (Reference 25), as a determining potential break location.

basis for selecting break locations because limiting conditions for ECCS strainer performance are not related to the pipe vulnerability issues addressed in BTP 3-4.

1.3.2.6 Licensees should consider locations that result in a unique Not applicable.

debris source term (i.e., not multiple, identical locations). The APR1400 design does not use microporous insulation in the Particular consideration should be given to breaks that result in containment.

the destruction of materials known to cause high head loss, such as microporous insulation (e.g., calcium silicate, Min-K, and Microtherm).

1.3.2.7 If the LOCA blowdown does not generate a significant amount Not applicable.

of fibrous debris, the contribution of latent debris sources may No fibrous debris is generated by LOCA blowdown in the become the limiting factor in ECCS strainer and downstream APR1400 design because RMI, which contains no fibrous evaluations. material, is used on components that may be subjected to jet impingement loads from a LOCA jet.

Conformance.

The APR 1400 design is used 90.72 kg (200 pounds) of latent debris in the evaluation of debris generation and 92.5% of the latent debris is considered particulate, and 7.5% is considered fibrous. These values are used for the evaluation of sump strainer performance.

1.3.2.8 If long-term cooling requires recirculation flow through the Conformance.

ECCS strainer for non-LOCA HELBs (e.g., main steam break, Main steam line break was used as the non-LOCA event in the feedwater line break), then licensees should use the same APR1400 evaluation of debris generation.

selection criteria for break locations as those specified for a LOCA.

KEPCO & KHNP A27

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix A - Comparison of IRWST Sump Strainer Design to NRC RG 1.82 Requirements NRC RG Regulatory Position APR1400 Design Features and Capabilities Item No.

1.3.3 Debris Generation/Zone of Influence Informational Material.

The initial pressure wave and erosion associated with the jet impingement can generate debris from the blowdown of a ruptured pipe. Insulation, coatings, fire barriers, shielding blankets, and other materials that are located within a material-dependent range of distances from the pipe rupture location can become debris as the result of the LOCA blowdown. The volume of space affected by this impact, or ZOI, is modeled to define and characterize the debris generated.

1.3.3.1 Zone of Influence Model Conformance.

a. The size and shape of the ZOI should be consistent with The method described in NEI 04-07 and the NRC SER for NEI experiments performed for specific debris sources (e.g., 04-07 is used for determining the ZOI in assessing debris insulation, coatings, fire barrier materials). The ZOI should generation for the APR1400.

extend until the pressure wave impulse and jet pressures decrease below the experimentally determined damage pressures appropriate for the debris source.

b. Licensees should use the volume of material contained Conformance.

within the ZOI to estimate the amount of debris generated The debris size distribution for RMI debris used in the APR1400 by a postulated break. The size distribution of debris debris generation evaluation is broken into two categories, 75%

created in the ZOI should be determined from applicable small fines and 25% large pieces, based on NEI 04-07 and the experiments. It is noted that if robust barriers intersect the NRC SER for NEI 04-07. Small fines are defined as debris postulated jet zone, the extended volume may be truncated capable of passing through openings in gratings, trash racks, and within the limitations of NEI 04-07, PWR Sump radiological fences that are smaller than a nominal 101.6 mm Performance Evaluation Methodology, Section 3.4.2.3, and (4 in). Thus, within small fines, there are fines and small pieces.

its associated SE (References 26 and 27).

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1.3.3.1 c. Licensees should use the pressure wave impulse and jet Conformance.

(cont.) impingement generated during the postulated pipe break as The APR1400 design uses the guidance provided in NEI 04-07 the basis for estimating the amount of debris generated and and the NRC SER for NEI 04-07 to determine the size or size the size or size distribution of the debris generated within distribution of debris generated within the ZOI.

the ZOI.

d. Licensees should perform debris generation testing to Not Applicable.

determine the ZOI in a manner that is prototypical of the The method described in the NEI 04-07 and NRCs SER for NEI plant condition. Test scaling is complicated because 04-07 is utilized for determining the ZOI in assess debris material destruction may result from both pressure waves generation of the APR1400.

and jet impingement. Scaling considerations for debris generation testing include the test fluid used (e.g., air or saturated water), the initial thermodynamic conditions of the test fluid, the rupture disk opening time, the blowdown period, the size and orientation of the test nozzle relative to the target, and the specific configuration of the target material to the various plant materials to which it is being applied (e.g., insulation jacketing seam, jacketing thickness, and banding and latching strength The staff has not developed specific guidance for the performance of ZOI testing. Methods and results are reviewed on a case-by-case basis. One example is the Air Jet Impact Tests documented in Section 3.2.1 of the NRC RG (Reference 15).

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1.3.3.1 e. If the evaluation uses simplified ZOI models, such as the Not applicable.

(cont.) spherical ZOI models that are discussed in Section 3.2.1 of As noted in Item 1.3.3.1, the APR1400 design use the spherical NEDO-32686-A (Reference 15) and Section 3.4.2 of NEI ZOI model described in the NEI 04-07 and NRCs SER for NEI 04-07 (References 26 and 27), licensees should apply 04-07. The APR1400 design has no problematic debris sufficient conservatism to account for simplifications and generated by LOCA blowdown.

uncertainties in the model. For example, a spherical ZOI model assumes that the blowdown from a LOCA is evenly distributed in all directions radiating from the break location.

Although, with sufficiently conservative inputs, a spherical model may be appropriate for estimating the loadings of debris within a ZOI, such a model does not account for non-uniform blowdown that could create damage in a particular direction at much greater distances from the break.

Therefore, such a spherical model would likely be non-conservative when specifying an exclusion zone for particularly problematic materials (e.g., calcium silicate insulation for a PWR with a trisodium phosphate buffer, fibrous debris for a plant with a limited strainer area that intends to demonstrate that a fibrous debris bed cannot be formed).

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1.3.3.2 Certain types of material used in small quantities inside the Conformance.

containment can, with adequate justification, be demonstrated The APR1400 uses the methodology outlined in the NEI 04-07 to make a marginal contribution to the debris loading for the guidance report and it is associated with NRC SER to determine ECCS sump. If debris generation and debris transport data the debris loading that will result in the maximum head loss have not been determined experimentally for such material, the across the sump strainer. The APR1400 evaluation material may be grouped with another material with similar conservatively assumed that all latent debris will be transported physical and chemical characteristics existing in large to the sump strainer and RMI debris will not be transported to quantities. For example, a small quantity of fibrous filtering sump strainer. All particulate and coating debris is assumed to be material may be grouped with a substantially large quantity of fine debris and 100% transported to the sump strainer. The fibrous insulation debris, and the debris generation and chemical debris that is generated during long-term recirculation is transport data for the filter material need not be determined considered in the strainer head loss evaluation.

experimentally. However, such analyses are valid only if the small quantity of material treated in this manner does not have a significant effect when combined with other materials (e.g.,

combining a small quantity of calcium silicate with fibrous debris may not be valid).

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1.3.3.3 All insulation (e.g., fibrous, calcium silicate, and reflective Conformance.

metallic); painted surfaces; fire barrier materials; and fibrous, All potential debris material within the ZOI that could adversely cloth, plastic, or particulate materials within the ZOI should be affect the operation of the ECCS and CSS following a LOCA is considered as potential debris sources. Licensees should use considered in the APR1400 debris generation evaluation.

applicable test data as the basis for predicting the size of the postulated debris. For breaks postulated in the vicinity of the containment penetrations, licensees should also consider the potential for debris generation from the packing materials used in the penetrations. In addition, licensees should consider breaks that could destroy the insulation installed on the pressure vessel. The potential for particulate debris to be generated by the action of pipe rupture jets stripping off paint or coatings and erosion of concrete at the point of impact should also be considered.

1.3.3.4 In addition to debris generated by jet forces from the pipe Conformance.

rupture, the analyses should consider (1) debris existing before Debris created by the resulting reactor pressure vessel the pipe rupture that is transported to the suppression pool, (2) environment (thermal and chemical) is considered in the debris created by the reactor pressure vessel environment APR1400 debris generation evaluation. This type of debris (i.e., thermal and chemical), (3) debris created by the includes disbandment of coating and formation of chemical atmospheric environment (i.e., thermal and chemical), and (4) debris (precipitants) caused by adverse chemical effects.

debris created by the environment of the submerged containment or suppression pool, as appropriate. Examples of debris created by the environment include disbanded coatings in the form of chips and particulates or the formation of chemical products caused by chemical reactions in the containment pool or the suppression pool or the reactor vessel (see Sections C.1.3.5 and C.1.3.10).

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1.3.3.5 The analyses should consider debris erosion that results from Not applicable.

continued degradation of insulation and other debris when The APR1400 evaluation assumed that the post-LOCA 30-day subjected to turbulence caused by cascading water flows from erosion of fiber insulation debris in containment is no longer upper regions of the containment or that result from the flows required to be considered because all the fiber debris is assumed in the sump or suppression pool or chemical decomposition. to be fines. The effect of erosion during post-LOCA 30-day The determination of eroded quantities for various types of operation is not required to be considered for RMI debris debris should be based on testing that is prototypical of plant characterization.

conditions. In the absence of applicable testing, demonstrably conservative assumptions should be used. (For example, the SE for NEI 04- 07 Appendix III (Reference 27) recommends using a bounding value of 90% erosion for fibrous debris).

1.3.4 Debris Transport Informational Material.

The debris transport evaluation determines the fraction of containment debris that is transported to the ECCS strainer.

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1.3.4.1 The calculation of debris quantities transported to the ECCS Conformance.

strainers should consider all modes of debris transport, The evaluation of debris quantities transported from debris including blowdown transport, spray transport, washdown sources to the sump strainer is conservatively bounded by the transport, and transport within the containment pool. assumption that all latent debris will be transported to the sump Consideration of containment pool debris transport should strainer and RMI debris will not be transported to sump strainer.

address (1) debris transport during the pool fill phase, as All particulate and coating debris is assumed to be small fine applicable, and during the recirculation phase, (2) the velocity debris and 100% transported to the sump strainer. The chemical and turbulence in the sump, suppression pool, or storage tank debris that is generated during long-term recirculation is (i.e., turbulence caused by the flow of water to the ECCS considered in the strainer head loss evaluation.

strainers, water splashing down from the break, containment spray drainage, and the discharge of pressure-relief flowpaths such as from downcomers, vents, and safety/relief valve spargers), and (3) the density, characteristic size, and other properties of the debris. Section 3.2.3 of the SE for NEDO-32686-A, (Reference 15), and Section 3.6 of the SE for NEI-04-07 (Reference 27) discuss staff accepted methods to evaluate debris transport. NUREG/CR-6369 (Reference 28) is also a useful reference document for debris transport evaluations. Section 3.6.4 of NEI 04-07 (Reference 26) contains a sample calculation for debris transport that the staff finds acceptable.

1.3.4.2 Transport analyses within the containment pool should include Conformance.

debris that may transport through the following modes: (1) See response to Item 1.3.4.1.

floating along a water surface, including debris that may float temporarily because of air entrapment, (2) traveling with the containment flow (i.e., debris suspended within the flow) because of neutral buoyancy or turbulence (e.g., individual fibers and fine particulates), and (3) settling to the floor and tumbling along the floor to reach the strainer.

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1.3.4.3 The debris transport analyses should consider each type of Conformance.

insulation (e.g., fibrous, calcium silicate, and reflective See response to Items 1.3.4.1 and 1.3.3.5.

metallic), other debris such as chemical precipitates, coatings, latent debris, and debris size (e.g., fine, readily suspendable, small, large, and intact). The analyses should also consider the potential for further decomposition of the debris as it is transported to the ECCS strainers.

1.3.4.4 An acceptable analytical approach to predict debris transport Not applicable resulting from fluid flows caused by long-term recirculation or Conservative assumptions regarding debris transport as provided pool fill is to use appropriately verified computational fluid in response to Item 1.3.4.1 are used in the APR1400; hence, use dynamics (CFD) simulations in combination with experimental of CFD is unnecessary.

debris transport data. The CDF simulations can be used to predict fluid flows, while debris transport thresholds can be determined experimentally. Section 4.2.4 of NEI 04-07 (Reference 26) and Section 4.2.4 and Appendix III in the associated SE (Reference 27) provide guidance and an example of this approach. Alternative methods for debris transport analyses are also acceptable, provided that they are supported by adequate validation of analytical techniques using experimental data to ensure that the debris transport estimates are conservative with respect to the quantities and types of debris transported to the strainer.

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1.3.4.5 The analysis may credit curbs for removing heavier debris that Not applicable.

has been shown analytically or experimentally to travel by Curbs are not considered in the APR1400 to maximize debris sliding along the containment floor and that cannot be lifted off transport to the sump strainer.

the floor within the calculated water velocity range. Curbs around the ECCS strainers may reduce or prevent some types of debris from transporting to floor- or pit-mounted strainers during the pool fill phase (see NUREG/CR-6772 (Reference

13) for limitations).

1.3.4.6 If transported to the containment pool, all debris that would Not applicable.

remain suspended because of turbulence (e.g., fine fibrous Conservative assumptions regarding debris transport as provided and particulates) should be considered to reach the ECCS in response to Item 1.3.4.1 are used for the APR1400.

strainers. However, if settlement of fine fibrous and particulate debris is credited during recirculation or pool fill, licensees should provide adequate theoretical and experimental basis to demonstrate that such settling is prototypical of plant conditions. This settlement analysis should include the potential for natural convection through the water column providing a motive force to keep the material in suspension.

1.3.4.7 In lieu of performing detailed blowdown and washdown debris Conformance.

transport analyses, licensees can conservatively assume that See response to Item 1.3.4.

all debris entering or originating in the sump or suppression pool is transported to the ECCS strainers when estimating strainer debris bed head loss.

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1.3.4.8 The effects of floating or buoyant debris on the integrity of the Not applicable.

ECCS strainers and on the strainer head loss should be As noted in Item 1.1.1.11, the top of each strainer is submerged considered during the initial filling of the sump (if applicable) below the surface of the IRWST water. The strainers are always and during recirculation. For strainers that are not fully fully submerged for the post-LOCA, which minimizes the effects submerged or are only shallowly submerged, floating debris of floating or buoyant debris on the integrity of the sump strainer could contribute to the debris bed head loss. Entrapped air and on subsequent head loss.

may cause some types of debris to temporarily float; the debris may then be transported to the vicinity of the ECCS strainers by surface currents and then sink on top of the strainers. A design feature (e.g., use of trash racks and solid cover plate) that keeps floating debris from reaching the sump or suppression pool strainer could reduce head loss caused by floating or buoyant debris.

1.3.4.9 Use of Debris Interceptors Not applicable.

Credit for the performance of debris interceptors upstream of No debris interceptors are installed or credited in the APR1400.

the ECCS strainers should be based on results of tests that are demonstrated to be either conservative or representative with respect to the plant condition.

If the interceptors are credited with capturing fine debris to reduce the ECCS strainer debris load, licensees should perform time-dependent analyses and tests that consider the conditions that would lead to minimum debris capture fractions.

This analysis also should include the potential of trapped debris further eroding into fines that could then pass through the interceptors. Iterative analyses of the flow in the sump or suppression pool (e.g., multiple computational fluid dynamics simulations that have been acceptably verified) may be necessary if the blockage of the interceptors has a significant impact on the containment pool flow pattern.

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1.3.5 Coating Debris Informational Material.

Coating debris is generated from the postulated failure (destruction) of both DBA-qualified and unqualified coatings within the ZOI and from the postulated failure of unqualified coatings outside the ZOI. NRC reports entitled, NRC Staff Review Guidance Regarding Generic Letter 2004-02 Closure in the Area of Coatings Evaluation, issued March 2008 (Reference 29), and Revised Guidance Regarding Coatings Zone of Influence For Review of Final Licensee Responses To Generic Letter 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents At Pressurized-Water Reactors, dated April 6, 2010 (Reference 30), provide a general approach to conducting plant-specific coatings evaluation.

1.3.5.1 Licensees should use a ZOI for coatings that is determined by Non Conformance.

applicable testing and plant specific analysis. The fluid used for A ZOI of 4D in the evaluation of the quantity of coating debris the test, i.e., steam, air, two-phase water, should be was used based on the NRC letter in 2010 (Reference [4] of representative of the plant exposure conditions. Appendix B).

1.3.5.2 All (100 percent) unqualified coatings should be assumed to Not applicable.

fail. However, licensees may also be able to demonstrate the Unqualified coatings are not used in reactor containment in the performance of their unqualified coatings through plant-specific APR1400. Hence, a coating-specific test is unnecessary.

and coating-specific testing.

1.3.5.3 Licensees should determine the debris characteristics (e.g., Conformance.

size, shape, density) of failed coatings separately for each Per Section 3.4.3.2 of NEI 04-07, all qualified coatings within the coating within containment. coating ZOI are assumed to fail and all qualified coatings located outside the coatings ZOI are considered not to fail. The size of coating debris is considered to be small fines.

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1.3.5.4 Licensees may determine coating chip debris transportability in Not applicable.

flowing water by using the results in NUREG/CR-6916 As noted in Item 1.3.4.1, all particulate and coating debris is (Reference 14) to the extent they apply to a licensees plant- assumed to be small fine debris and 100% transported to the specific coating types. sump strainer.

1.3.6 Latent Debris

a. Latent debris present in containment during operation may Conformance.

contribute significantly to head loss across the ECCS As noted in Item 1.3.2.7, 90.72 kg (200 lbm) of latent debris was strainers. Licensees must determine the types, size, used in the APR1400 debris generation evaluation. The 92.5% of quantities, and locations of latent debris. NEI 04-07, and its the latent debris is considered particulate and 7.5% is considered associated SE (Reference 26 and 27), provide general fibrous.

considerations for latent debris in terms of its potential impact on strainer blockage and some plant-specific variables. In collecting latent debris samples for analysis, licensees should use a sampling technique with demonstrated collection efficiency for fine particulate and fibrous debris. NEI 02-01, Condition Assessment Guidelines: Debris Sources inside PWR Containments, dated September 30, 2002 (Reference 31), provides an accepted approach for determining latent debris quantities.

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1.3.6 b. Applicants or licensees should not assume that their Conformance.

(cont.) (existing) foreign material exclusion programs have entirely See responses to Items 1.1.2.1 and 1.1.2.2.

eliminated miscellaneous debris. Results from plant-specific walkdowns should be used to determine a realistic amount of latent debris in containment and to monitor cleanliness programs for consistency with committed estimates.

Evaluation of the results of latent debris walkdowns should include sufficient conservatism to account for substantial uncertainties inherent in the debris sampling and collection process. In lieu of plant-specific walkdowns, 10 CFR Part 52 applicants may perform conservative analyses that are based on latent debris measurements made for operating plants.

1.3.7 Upstream Effects

a. Section 7.2 of the staffs SE on NEI 04-07 (Reference 27) Conformance.

provides guidance on evaluating the flowpaths upstream of The APR 1400 design is evaluated for upstream effects to assess the PWR containment sump for the holdup of inventory, the flowpaths upstream of the IRWST sump for holdup of which could limit flow to, and possibly starve, the suction inventory that could reduce flow to and possibly starve the sump.

strainer. A similar approach may be used for BWRs.

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1.3.7 b. Licensees should use the results of their debris Conformance.

(cont.) assessments to estimate the potential for water inventory See responses to Items 1.1.1.2, 1.3.4.5, and 1.3.4.9.

holdup. Based on these assessments and the mapping of probable flowpaths, licensees should determine whether trash racks or debris interceptors are necessary to protect flowpaths in upper containment to prevent the holdup of water upstream of the sump, storage tank, or suppression pool. Licensees should also evaluate the effect that the placement of curbs and debris interceptors may have on the holdup of water en route to the sump, storage tank, or suppression pool.

1.3.8 Downstream Effects

a. Debris may be carried downstream of the ECCS strainer, Conformance.

thus causing downstream blockage or wear and abrasion. The APR1400 downstream effects evaluation of debris ingestion The three areas of concern identified are (1) blockage of on the auxiliary equipment, including the pumps, heat system flowpaths at narrow flow passages (e.g., exchangers, orifices, spray nozzles, and instrumentation tubing, containment spray nozzles, some pump internal flow follow the methodology in WCAP-16406-P-A.

passages, and tight-clearance valves), (2) wear and abrasion of surfaces (e.g., pump running surfaces) and heat exchanger tubes and orifices, and (3) blockage of flowpaths through fuel assemblies.

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1.3.8 b. The quantity and size characteristics of this strainer bypass Informational Material.

(cont.) debris will be unique to each strainer vendor and plant-specific debris mixtures and should be determined during strainer head loss tests, as discussed in Section 1.3.12.g.

WCAP-16406-P-A (Reference 21) provides a method that the NRC considers acceptable for PWR licensees to use in evaluating the downstream impact of sump debris on the performance of their ECCSs, CSSs, and components following a LOCA. The NRC has received WCAP-16793-NP (Reference 23) for review.7 This report provides a method and reference for PWR licensees whose plants are bounded by its input assumptions to use in evaluating the downstream impact of sump debris on the performance of fuel following a LOCA, subject to the conditions and limitations specified in the NRC SE to be prepared for WCAP-16793-NP, Revision 2. Neither of these reports applies to BWRs at this time.

1.3.9 Strainer Structural Analysis This Regulatory Position also applies to trash racks and debris Interceptors, if used.

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1.3.9.1 General items identified for consideration in the structural Conformance.

analyses should include (1) the verification of maximum The strainers are installed away from the spargers to minimize differential pressure caused by the combined clean strainer the effect of hydrodynamic loads induced by the discharge of and worst case debris scenario at rated flow rates or maximum water, air, and single- and two-phase steam due to the opening of realistic flow rates, whichever is greater, (2) geometry concerns the pressurizer POSRVs into the IRWST.

(i.e., mesh and frame versus perforated plate), (3) ECCS Strainers are designed to seismic Category I and quality Class Q.

strainer material selection for the post-accident environment The structural analysis of the strainer is performed to verify the (i.e., corrosion-resistant materials that can withstand the post-structural adequacy of the sump strainer, including seismic, LOCA environment), and (4) the addition of hydrodynamic differential pressure, and hydrodynamic loads.

loads.

The strainers are made of stainless steel materials that resist degradation during inactive periods and resist degradation in the chemically reactive post-LOCA environment.

1.3.9.2 Licensees should compute structural loads on a strainer using Conformance.

the maximum pressure drop across the strainer. Licensees See response to Item 1.3.9.1.

should also evaluate the limiting conditions corresponding to the break location and debris source term that induce the maximum total head loss at the ECCS strainer.

1.3.9.3 For some licensees, the minimum structural design criterion for Conformance.

the ECCS strainer can depend on the plants NPSH margin. See response to Item1.3.9.1.

Plant-specific licensing bases may dictate the structural capacity of the ECCS strainer for supporting water flow through a debris bed under recirculation velocities, depending on strainer geometry (i.e., fully submerged versus partially submerged or vented designs).

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1.3.9.4 Load combinations (e.g., safe-shutdown earthquake, Conformance.

deadweight, crush pressure, thermal, and live loads) used for The sump strainers are safety-related components and are structural analysis should be performed in accordance with the designed to meet the APR1400 seismic Category I requirements specific plant licensing basis requirements and the applicable based on NRC RG 1.92.

design code of record. Licensees should also reference Regulatory Guide 1.92, Combining Modal Responses and Spatial Components in Seismic Response Analysis (Reference 32), when analyzing the seismic loading conditions during the structural analyses of the strainers.

1.3.9.5 Licensees should include the effects of the fluid temperature Conformance.

and containment ambient temperature (e.g., restrained thermal See response to Item 1.3.9.1.

growth, temperature dependent material properties) in determining the structural integrity of the strainer.

1.3.9.6 Licensees should perform an evaluation to determine the Conformance.

possibility for dynamic loading on the strainers caused by See response to Item 1.3.9.1.

HELBs and other structures, systems, and components that could produce missiles, pipe whipping, or jet impingement loads. Chugging and condensation oscillation loads can be a significant contributor in some BWR designs. This evaluation should be done in accordance with GDC 4 and should be based on the plants design basis for postulated dynamic effects within the region of the strainers. Based on the SE for NEI 04-07 (Reference 27), in general, if a postulated pipe break is located more than 10 pipe diameters away from the strainer, the dynamic effects of such a break may be neglected with respect to the structural integrity effects on the strainer.

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1.3.10 Chemical Reaction Effects

a. Chemical reaction products in the post-LOCA environment Conformance.

of containments can contribute to blockage of the ECCS A chemical effects analysis was performed for the APR1400. The strainers and increase the associated head loss. The final quantity of chemicals dissolved in the post-LOCA sump pool is SE by the Office of Nuclear Reactor Regulation on WCAP- determined using WCAP-16530-NP and associated letters and 16530-NP-A (Reference 24), and the NRC report entitled, SE. The dissolved chemical quantities along with the boron and NRC Staff Review Guidance Regarding Generic Letter phosphate concentrations due to the borated sump water and 2004-02, Closure in the area of, Plant-Specific Chemical TSP, respectively, were considered in the evaluation of chemical Effect Evaluations (Reference 33), provide a general effects.

approach to conduct plant-specific chemical effects evaluation.

b. During a LOCA, materials in the ZOI of the break can Conformance.

become debris that may transport to the containment pool As part of the APR1400 IRWST strainer performance evaluation, where spray solution, spilled reactor coolant, and water a chemical effects evaluation was conducted to identify specific from other safety injection sources accumulate. compounds and quantities of materials that may precipitate within Subsequently, the combination of spray chemicals, the reactor containment sump pool following a LOCA. An insulation, corroding metals, and submerged and analysis was performed to determine the types and quantities of unsubmerged materials can create a potential condition for chemical precipitates that may form in the post-LOCA the formation of chemical substances that may impede the recirculation fluid for the APR1400 design.

flow of water through the ECCS suction strainers or downstream components in the ECCS, CSS, or reactor coolant system.

c. New reactors with configurations different than those of Conformance.

operating PWRs (e.g., different containment materials, lack See responses to Items 1.1.2.5, 1.3.10.a, and 1.3.10.b.

of buffering agents) may require additional evaluation.

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1.3.11 Debris Accumulation, Head Loss, and Vortexing Informational Material.

a. In a letter to NEI dated March 28, 2008 (References 4 and 8), the NRC provided guidance for evaluating the potential for debris accumulation and its impact on strainer head loss during a LOCA that could impede or prevent the ECCS or CSS from performing its intended safety functions.

b. Testing and analyses performed to address GL 2004-02 indicate that the maximum head losses for the ECCS strainers in some plants can occur when a layer of fiber just thick enough to fully cover the strainer accumulates on the strainer along with a bounding quantity of fine particulate matter. This case may result in a thin, dense debris bed with low porosity that could maximize head loss. The thickness of the fiber layer necessary to filter fine particulate cannot be specified in general, but it is dependent on a number of factors, including the strainer design, the strainer geometry and orientation, the approach velocity, the type and size of the fibrous debris, the type of particulate debris, and the presence of chemical effects. Appendix A, Section 6, of Reference 8 provides testing methods acceptable to the NRC staff to evaluate thin bed effects.

1.3.11 c. Other testing and analyses have shown that the maximum (cont.) debris loading case can also be a limiting head loss condition for strainers. Therefore, licensees should test for both the thin-bed and maximum loading cases. If the maximum debris loading case can result in a circumscribed debris accumulation, licensees should ensure that the strainer design and head loss test scaling accounts for this effective reduction in the strainer surface area.

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1.3.11.1 Debris accumulation on the ECCS strainers for the head loss Conformance.

evaluation should be based on the amount of debris generated The performance of the sump strainers is based on conservative and the formation of different combinations of fibers and assumptions relative to the quantity of debris, ECC and CS flow, particulate mixtures (e.g., a fiber bed with a minimum thickness and temperature conditions.

necessary to effectively filter particulate debris, as well as maximum debris loading) using the guidelines described in Section C.1.3.3 and on the debris transported to the strainers in accordance with Section C.1.3.4. The evaluation should be based on plant-specific debris loads determined in accordance with these regulatory positions.

1.3.11.2 The degree of ECCS strainer submergence (full or partial) at Not applicable.

the time of switchover to recirculation should be considered in Following an accident, water spilled from an RCS break and the calculating the available (wetted) screen area. For plants in uniformly distributed CS water drains back to the HVT. The water which certain pumps take suction from the ECCS strainers drains into the HVT and is ultimately returned to the IRWST before the switchover of other pumps, the available NPSH for through the IRWST spillways, by gravity, once the HVT water these pumps should consider the submergence of the strainers level reaches the IRWST spillways. The APR1400 eliminates the at the time these pumps initiate suction through the strainers. need to switch over from the injection mode to the recirculation Unless otherwise shown experimentally, licensees should mode.

assume that debris is uniformly distributed over the available strainer surface.

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1.3.11.3 Strainer submergence should be adequate to preclude Conformance.

vortexing, sump fluid flashing, and deaeration induced by The top of each strainer is submerged below the surface of the excessive differential pressure drop. Vortexing can cause the IRWST water. The minimum water level is sufficient to preclude ingestion of unacceptable quantities of air into the ECCS and adverse hydraulic effects (e.g., vortex formation, sump fluid CSS pumps, potentially resulting in unacceptable pump flashing, and deaeration).

performance. Water, when flashing to steam, can result in recirculating coolant that transforms a portion of the fluid into the vapor phase if the strainer pressure drop is sufficiently large. For partially submerged strainers, licensees should evaluate the potential for vortex formation internal to the strainer. Deaeration can similarly result in ingested air and unacceptable pump performance, whereas both deaeration and sump fluid flashing can result in an unacceptable increase in strainer head loss caused by the increased resistance associated with two-phase flow.

1.3.11.4 Licensees should validate the adequacy of ECCS strainer Conformance.

designs through testing applicable to plant-specific conditions. See response to Item 1.3.2.3.

Analytical or empirical head loss correlations should not be used to validate plant-specific debris bed head losses.

However, correlations may be useful in conducting scoping evaluations for conditions and debris loads with the range of applicable test data.

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1.3.12 Prototypical Head Loss Testing

a. The methodology to predict the key inputs to the head loss Conformance.

testing has been conservatively developed and The performance of the IRWST sump strainers is based on documented in NEI 04-07, referred to as the guidance conservative assumptions relative to the quantity of debris, ECCS report and its associated SE (References 26 and 27). flow, and temperature conditions. The strainer design provides Additionally, the NRC staff review guidance (Reference 8) sufficient strainer area for acceptable strainer head loss under provides a general approach to conducting plant-specific debris laden conditions. The strainer head loss is validated by testing. The APR1400 design is such that the IRWST sumps prototype head loss testing. This guidance report document remain continuously submerged.

discusses the staff positions on various aspects of head loss testing including scaling of the plant strainer design to the test strainer module, similitude considerations for debris transport and debris accumulation on the strainer, surrogate debris similitude requirements, and posttest data processing extrapolation.

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1.3.12 b. The objective of prototypical head loss testing is to Conformance.

(cont.) determine the potential peak or bounding head loss that The prototypical head loss test is designed in accordance with could occur across a suction strainer debris bed during a the head loss testing guidance provided in NRC Staff Review postulated LOCA scenario. If the test facility is scaled Guidance Regarding Generic Letter 2004-02 Closure in the Area properly and the testing procedures are conservative, the of Strainer Head Loss and Vortexing dated March 2008. This staff measured head loss is also expected to be conservative. To guidance provides acceptable methods to perform prototype strainer head loss testing. Further details regarding the strainer ensure adequate strainer function, licensees should design head loss test are discussed in Reference [3-5] and Appendix C.

the test facility properly and conduct testing following conservative testing procedures. The conditions within the test tank should be prototypical or conservative with respect to the plant, including the postulated debris loading, the recirculation system hydraulics, and key aspects of various accident scenarios. The primary scaling parameters include the screen area, the dimension of the strainer elements (e.g., disks), and the submergence level, the number of strainer elements, the debris amounts, and the local fluid flow conditions, as applicable. These parameters affect the flow velocities approaching the test strainer and the velocities through accumulated debris.

c. The test specifications should be designed to determine a Conformance.

reasonably bounding head loss from all of the possible See response to Item 1.3.2.3.

types of debris beds that could accumulate on the strainer considering the plant specific debris quantities that would transport.

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1.3.12 d. Post-test evaluations are required to validate the head loss Conformance.

(cont.) results, apply the results to the proposed strainer, and See response to Item 1.3.12.b.

ensure that the debris penetrating the strainer cannot cause adverse effects to downstream equipment. Licensees that want to scale the results of head loss tests conducted using colder water to the plant water temperatures should ensure that boreholes, bed degradation, open strainer area, or other phenomena that could affect the head loss response of the debris bed do not have a non-conservative effect when the temperature is scaled. The NRC does not recommend scaling of head loss results to alternate approach velocities or debris loadings because the theoretical debris bed head loss behavior is not well understood and the results of experiments examining these parameters have varied.

e. Licensees may need to extrapolate the results of head loss Conformance.

testing for a time period matching the mission time of the See response to Item 1.3.12.b.

ECCS. The method of extrapolation used should be one that conservatively fits the data (e.g., linear, log, quadratic) over the time period of interest.

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1.3.12 f. Because of the complexity of modeling and scaling multiple, Conformance.

(cont.) complex physical phenomena in a single test, licensees See response to Item 1.3.12.b.

should conduct head loss tests in a manner that ensures complete transport of debris (as determined by transport analysis) to the test strainer. Agitation of the test fluid with stirrers may be necessary to achieve conservative debris transport. If desired, licensees may conduct separately testing to credit reductions in debris transport (i.e., settling) to the strainer under conditions that are conservatively or prototypically scaled to the plant condition. However, strainer head loss testing that credits debris settlement within the test tank should carefully evaluate the flow characteristics (e.g., velocity and turbulence) in the test to ensure that the simulated flows are prototypical or conservative with respect to the plant condition. Licensees should consider scaling of debris per unit area of floor in the flume versus debris per unit floor area of the plant with respect to effects on debris transport caused by potential piling up of debris in areas of flow restrictions. The quantity of debris per unit width of the flume relative to the flow passages in the plant is also an important scaling parameter. Licensees should also give special consideration to the adequacy of other aspects of the test protocol, such as debris preparation, addition sequencing, debris concentration in the flume, and test flume geometry, to conclude that similar or larger amounts of debris settling would occur in the plant containment. Consideration should also be given to how debris settlement during a head loss test impacts other aspects KEPCO & KHNP A52

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1.3.12 of the analysis. For example, allowing debris to settle in the Conformance.

(cont.) test tank can lead to a failure to account for erosion of this See response to Item 1.3.12.b.

settled debris in the analysis. Because of the practical inability to simultaneously scale multiple, complex phenomena associated with debris transport and head loss in a rigorous way, licensees should apply conservatism to tests that model both transport and head loss. Section 4.0 of Appendix A of Reference 8 provides more details on this topic.

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1.3.12 g. Licensees may sample the flows downstream of the test Conformance.

(cont.) strainer to determine the amount of debris passing through See response to Item 1.3.12.b.

the strainer. The sampling should be performed on a frequency that ensures adequate characterization of the total bypass content. This debris could potentially damage or clog components, such as pumps, throttling valves, or components within the reactor core. Licensees may use the downstream debris characteristics to determine the likelihood that downstream blockage or wear and abrasion could threaten long-term core cooling or impact heat transfer of the fuel cladding. The conditions for the limiting downstream sampling tests will typically differ from the conditions for the limiting debris bed head loss tests because a filtering debris bed will tend to reduce the quantity of debris that passes through the strainer. A large strainer surface area, higher ECCS flow rates, low rate of debris introduction into the water, or thinner debris beds can result in higher quantities of bypass debris. Licensees may need to conduct separate strainer pass-through tests for fibrous and particulate debris to avoid crediting filtration caused by one debris type that might affect the other debris type. Collecting bypass debris in a filter with very small pore size, downstream of the strainer has also been successfully used to characterize the bypass content8.

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1.3.12 h. The analyses and testing should consider worst-case single Conformance.

(cont.) failures. For example, licensees with plant designs that See response to Item 1.3.12.b.

include low-pressure safety injection (LPSI) pumps that shut down during the switchover from the refueling water storage tank to the sump should consider one LPSI train failure to stop. This assumption leads to a conservatively calculated maximum flow rate to and through the screen.

i. The time dependence of debris arrival at the strainer is Conformance.

difficult to model in a practical number of head loss tests. A See response to Item 1.3.12.b.

conservative assumption is that all of the LOCA debris is present on the strainer at the beginning of recirculation.

This debris should include the debris generated from the LOCA blowdown, failed unqualified coatings, eroded fine debris, chemical precipitates, and all other debris predicted to transport to the strainer.

j. Head loss testing for complex combinations of debris that Conformance.

typically result from limiting plant debris loads has, in some See response to Item 1.3.12.b.

cases, shown significant variation for the same debris loading. As a result, licensees should ensure that head loss test results have been demonstrated to be sufficiently repeatable, in light of known margins, uncertainties in debris quantities, the collective body of knowledge from tests on similar strainers, and other relevant information.

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1.3.12 k. Proper debris introduction procedures should take into Conformance.

(cont.) account the fact that variations in the sequence and rate of See response to Item 1.3.12.b.

debris introduction can potentially affect the head loss measurement. The approach that is considered most conservative is to introduce the debris slowly into the test tank with the pump running and prototypical hydraulic conditions established. The most transportable debris should be added first and the least transportable last.

Licensees may also use other approaches, if justified.

Testing that takes credit for near-field settlement should either realistically or conservatively simulate the strainer upstream flow and turbulent conditions. Licensees should conduct proper analytical evaluation of the similitude between the test tank and the actual plant condition. The NRC staff considers computational fluid dynamic codes to be useful tools to assist the evaluation. Surrogate debris materials used in head loss testing should be either the actual plant materials or suitable substitutions. Licensees should justify substitutions by comparing the important characteristics of the plant debris sources and the surrogate to ensure that the debris preparation creates prototypical or conservative debris characteristics.

2 Regulatory Positions Specific to Pressurized Water Informational Material.

Reactors Any evaluation of the susceptibility of a PWR to debris blockage should address the considerations and events shown in Figure 3 (see page 33).

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2.1 Emergency Core Cooling System Sumps, Strainers, and Conformance.

Debris Interceptors Four separate, independent, and redundant trains of the SIS and Distribution of water sources and containment spray between CSS with two SI pumps and one CS pump in each division are the sumps should be considered in the calculation of boron provided. Within each division, the two SI trains (and each CS concentration in the sumps for evaluating post-LOCA train) are separated by a quadrant wall to isolate the trains from subcriticality and shutdown margins. Typically, these each other to the maximum extent practical. Each of the four SI calculations are performed assuming minimum boron pumps has its own suction connection to the IRWST and each of concentration and maximum dilution sources. Similar two CS pumps shares one of these four connections. The four considerations should also be given in the calculation of time sumps are provided in the IRWST. Each IRWST sump contains for hot-leg switchover, which is calculated assuming maximum paired CSS/SCS and SI suction pipes (two sumps: SI and CS boron concentration and a minimum of dilution sources. pump suction pipes, two sumps: SI and SC pump suction pipes).

Additionally, the evaluation of debris transport to the sump Each pair of CSS/SCS and SI suction pipes ends in a suction screen should consider the time to switch over to sump sump, with each suction sump installed adjacent to an associated recirculation and the operation of containment spray. strainer (total four strainers). The IRWST contains approximately 3

2,456.7 m (649,000 gal) of 4,000 ~ 4,400 ppm boric acid at pH 3.8 ~ 10.5. To minimize the corrosion of stainless steel in containment during a LOCA, long-term post-LOCA pH control (between 7.0 and 10.0 within the first 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, between 7.0 and 8.5 up to 30 days after 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />) of the IRWST water is provided by granular trisodium phosphate (TSP), which is stored in the HVT. The stainless steel TSP storage baskets have a solid top and bottom with mesh sides to provide reasonable assurance of dissolution when submerged in water.

The risk of dilution is considered negligible because the amount of diluent required to achieve a significant reduction in boron concentration is unrealistic (i.e., without being undetected).

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2.1.1 The ECCS strainers should be located on the lowest general Conformance.

area floor elevation in the containment, exclusive of the reactor The methodology described in NEI 04-07 and the associated vessel cavity and the normal drainage sump, to maximize the NRC SER was used to perform the analysis of susceptibility of pool depth relative to the strainers. Design considerations for the ECCS and CSS recirculation functions to the adverse effects recirculation strainers should ensure that they protect the pump of post-accident debris blockage and operation with debris-laden inlets for which they supply water. A curb could be provided fluids.

upstream of the strainers to prevent high-density debris from being swept along the floor into the sump strainer. To be effective, the height of the curb should be appropriate for the pool flow velocities and plant debris types because debris can be carried over a curb if the velocities are sufficiently high.

Estimation of pool flow velocities should include both the pool fill (as applicable) and recirculation phases of the event.

Licensees should also consider that turbulence in the pool may keep some debris in suspension that would otherwise settle.

Experiments documented in NUREG/CR-6772 (Reference 13) and NUREG/CR-6916 (Reference 14) demonstrated that some types of settled debris could transport across the containment pool floor to the suction strainer by sliding or tumbling at typical containment pool velocities.

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2.1.1 The ECCS strainer structures should include access openings (cont.) and other design features, as required, to facilitate inspection of the strainer structures, any vortex suppressors, and the pump suction piping inlets. Where consistent with overall design and functionality, the top of the ECCS strainer structures should be a solid cover plate that is designed to be fully submerged after a LOCA and completion of the ECCS injection from the water storage tank. The cover plate is intended to provide additional protection to debris interceptor structures from LOCA-generated loads and from water drainage from upper containment. However, the design should also provide a means for venting any air trapped underneath the cover.

2.2 Chemical Reaction Effects

a. The Westinghouse report, WCAP-16530-NP-A, and the Conformance.

limitations discussed in the associated SE (Reference 24) See response to Item 1.3.2.

provide an acceptable approach for PWRs to evaluate chemical effects that may occur in a post-accident containment sump pool.

b. Plant-specific information should be used to determine Conformance.

chemical precipitate inventory in containment. However, See response to Item 1.3.10.

plant specific chemical effect evaluations should use a conservative analytical approach. Additionally, NRC Staff Review Guidance Regarding Generic Letter 04-02 Closure in the Area of Plant-Specific Chemical Effect Evaluations (Reference 33) provides a general approach for PWR licensees to conduct plant-specific chemical effect evaluations.

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(Cont.) Considering Particulate, Fibrous and Chemical Debris in the The testing and analysis were performed for in-vessel Recirculating Fluid, (Reference 23) is still under review by downstream effects using the methodology developed in WCAP-the NRC staff. When approved by the staff, it, along with 16793-NP to demonstrate reasonable assurance that sufficient the SE, will provide guidance for evaluation of chemical LTCC is achieved for PWRs to satisfy the requirements of 10 debris within the reactor. CFR 50.46 for debris and chemical products that might be transported to the reactor vessel and core by the coolant recirculating from the containment sump.

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Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix B Debris Generation Evaluation for the APR1400 KEPCO & KHNP B 1

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TABLE OF CONTENTS B.1 INTRODUCTION...................................................................................................... 5 B.2 EVALUATION OF INSULATION DEBRIS GENERATION ........................................... 7 B .2.1 Insul ation Deb ris Generation f rom an RCS Hot L eg L ine B reak ( 42 inc h es) ................................. 7 B .2.2 Insul ation Deb ris Generation f rom an RCS Col d L eg L ine B reak ( 30 inc h es) ............................... 8 B .2.3 Insul ation Deb ris Generation f rom a M ain Steam L ine B reak ( 30.907 inc h es) .............................. 9 B.3 EVALUATION OF COATING DEBRIS GENERATION .............................................. 10 B .3.1 Coating Deb ris Generation f rom an RCS Hot L eg L ine B reak ( 42 inc h es) .................................. 12 B .3.2 Coating Deb ris Generation f rom an RCS Col d L eg L ine B reak ( 30 inc h ) .................................... 13 B .3.3 Coating Deb ris Generation f rom a M ain Steam L ine B reak ( 30.907 inc h es) ............................... 14 B.4 EVALUATION OF LATENT DEBRIS GENERATION ................................................ 15 B.5 CONCLUSION ....................................................................................................... 16 B.6 REFERENCES ....................................................................................................... 17 KEPCO & KHNP B

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF TABLES T ab l e B .1-1 Destruc tion Pressures and Assoc iated Z OI Radii f or M aterial s f rom T ab l e 3-2 of th e SE of NEI 04-07 ( Ref erenc e [ 1-2] ) ...................................................................................... 6 T ab l e B .2-1 RM I Generated f rom an RCS Hot L eg L ine B reak .............................................................. 8 T ab l e B .2-2 RM I Generated f rom an RCS Col d L eg L ine B reak ............................................................. 8 T ab l e B 2-3 RM I Generated f rom a M ain Steam L ine B reak .................................................................. 9 T ab l e B .3-1 Coating M aterial s and Coating T h ic k ness inside Containm ent ......................................... 11 T ab l e B .3-2 Ep ox y Coating ( 4D) Generated f rom an RCS Hot L eg L ine B reak ................................... 12 T ab l e B .3-3 IOZ Coating ( 10D) Generated f rom an RCS Hot L eg L ine B reak ..................................... 12 T ab l e B .3-4 Ep ox y Coating ( 4D) Generated f rom an RCS Col d L eg L ine B reak .................................. 13 T ab l e B .3-5 IOZ Coating ( 10D) Generated f rom an RCS Col d L eg L ine B reak .................................... 13 T ab l e B .3-6 Ep ox y Coating ( 4D) Generated f rom a M ain Steam L ine B reak ....................................... 14 T ab l e B .3-7 IOZ ( 10D) Generated f rom a M ain Steam L ine B reak ....................................................... 14 T ab l e B .5-1 Deb ris Generation f or Eac h B reak L oc ation ...................................................................... 16 KEPCO & KHNP B

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF FIGURES Figure B .1-1 Sec tional V iew of Z OI f or an RCS Hot L eg L ine B reak ( 2D f or RM I; 4D and 10D f or Coating) ............................................................................................................................. 18 Figure B .1-2 Sec tional V iew of Z OI f or an RCS Col d L eg L ine B reak ( 2D f or RM I; 4D and 10D f or Coating) ............................................................................................................................. 19 Figure B .1-3 Sec tional V iew of Z OI f or a M ain Steam L ine B reak ( 2D f or RM I; 4D and 10D f or Coating) ............................................................................................................................. 20 Figure B .2-1 3D M odel V iew of 2D Z OI f or an RCS Hot L eg L ine B reak ............................................... 21 Figure B .2-2 3D M odel V iew of 2D Z OI f or an RCS Col d L eg L ine B reak ............................................. 22 Figure B .2-3 3D M odel V iew of 2D Z OI f or a M ain Steam L ine B reak ................................................... 23 Figure B .2-4 Sep arate Parts of Surf ac e Areas f or an RCS Hot L eg L ine B reak ( 2D Z OI) ..................... 24 Figure B .2-5 Sep arate Parts of Surf ac e Areas f or an RCS Col d L eg L ine B reak ( 2D Z OI) ................... 25 Figure B .2-6 Sep arate Parts of Surf ac e Areas f or a M ain Steam L ine B reak ( 2D Z OI) ......................... 26 Figure B .3-1 3D M odel V iew of th e D-Ring of Steam Generator No.2 Com p artm ent ............................ 27 Figure B .3-2 3D M odel V iew of 4D Z OI f or an RCS Hot L eg L ine B reak ............................................... 28 Figure B .3-3 3D M odel V iew of 10D Z OI f or an RCS Hot L eg L ine B reak ............................................. 29 Figure B .3-4 Sep arate Parts of Surf ac e Areas f or an RCS Hot L eg L ine B reak ( 4D Z OI) ..................... 30 Figure B .3-5 3D M odel V iew of Surf ac e Areas f or an RCS Hot L eg L ine B reak ( 10D Z OI) ................... 31 Figure B .3-6 3D M odel V iew of 4D Z OI f or an RCS Col d L eg L ine B reak ............................................. 32 Figure B .3-7 3D M odel V iew of 10D Z OI f or an RCS Col d L eg L ine B reak ........................................... 33 Figure B .3-8 Sep arate Parts of Surf ac e Areas f or an RCS Col d L eg L ine B reak ( 4D Z OI) ................... 34 Figure B .3-9 3D M odel V iew of Surf ac e Areas f or an RCS Col d L eg L ine B reak ( 10D Z OI) ................. 35 Figure B .3-10 3D M odel V iew of 4D Z OI f or a M ain Steam L ine B reak ................................................... 36 Figure B .3-11 3D M odel V iew of 10D Z OI f or a M ain Steam L ine B reak ................................................. 37 Figure B .3-12 Sep arate Parts of Surf ac e Areas f or a M ain Steam L ine B reak ( 4D Z OI) ......................... 38 Figure B .3-13 3D M odel V iew of Surf ac e Areas f or a M ain Steam L ine B reak ( 10D Z OI) ....................... 39 KEPCO & KHNP B

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.1 INTRODUCTION T h e p otential sourc es of deb ris in th e Advanc ed Pow er Reac tor 1400 ( APR1400) are insul ation, c oating, and l atent deb ris. T h e Ref l ec tive m etal insul ation ( RM I) and c oating deb ris are c onsidered th e p otential sourc e of deb ris f ol l ow ing a h igh -energy l ine b reak ( HEL B ) .

T h e sp h eric al z one of inf l uenc e ( Z OI) is used in estim ating deb ris generation. T h e Z OI is def ined as th e vol um e ab out a given HEL B area in w h ic h th e f l uid esc ap ing f rom th e b reak h as suf f ic ient energy to generate deb ris f rom insul ation, c oatings, and oth er m aterial s w ith in th e z one. Nuc l ear Energy Institute

( NEI) 04-07 ( Ref erenc e [ 1-1] ) def ines th e Z OI as sp h eric al and c entered at th e b reak site or l oc ation.

T h e radius of th e sp h ere is determ ined b y th e p ip e diam eter and th e destruc tion p ressures of th e p otential target insul ation or deb ris m aterial . Al l signif ic ant deb ris sourc es ( e.g., insul ation, deb ris) w ith in th e Z OI are eval uated. T h e destruc tion p ressures and assoc iated Z OI radius f or m aterial used in th e APR1400 are tak en f rom T ab l e 3-2 of th e Saf ety Eval uation ( SE) of NEI 04-07 ( Ref erenc e [ 1-2] ) , and are p rovided in T ab l e B .1-1 of th is ap p endix .

In ac c ordanc e w ith th e guidanc e in Sec tion 3.4.2.3 of th e SE of NEI 04-07 ( Ref erenc e [ 1-2] ) , w h en a sp h eric al Z OI ex tends b ey ond a rob ust b arrier, th e b arriers m ay p revent ex p ansion of th e b reak j et, b ut it c an al so c ause def l ec tion and ref l ec tion. Sec tion 3.4.2.3 of th e SE of NEI 04-07 ( Ref erenc e [ 1-2] ) states th at w h en a sp h eric al Z OI ex tends b ey ond rob ust b arriers suc h as w al l s or enc om p asses l arge c om p onents suc h as tank s and steam generators, th e ex tended vol um e m ay b e c onservativel y trunc ated.

T h e SE of NEI 04-07 al so stip ul ates th at " sh adow ed" surf ac es of c om p onents are inc l uded in th e anal y sis.

T h ese ap p roac h es are used f or th e eval uation of deb ris generation. T h e b oundary of th e sp h eric al Z OI is c onservativel y trunc ated. T h e c al c ul ation assum es th at al l RM I w ith in th e Z OI b ec om es deb ris.

A th ree-dim ensional ( 3D) c om p uter-aided design ( CAD) m odel b ased on struc tural draw ings is devel op ed f or th e APR1400 and is used to eval uate deb ris generation. T h e m odel inc l udes th e struc ture of th e l ow er and up p er c ontainm ent, c om p onents, and p ip es and is used to assist in th e identif ic ation of deb ris sourc es and rob ust b arriers w ith in a given Z OI. T h e f igures used in th is ap p endix w ere devel op ed f rom th e 3D CAD m odel .

For th e p ostul ated b reak , a Z OI sp h ere is p l ac ed in th e m odel c entered at th e b reak l oc ation. T h e c oated surf ac e area w ith in th e c oating Z OI is th en determ ined using various f eatures of th e 3D CAD m odel .

Credit is tak en in a c onservative m anner f or som e areas sh iel ded b y rob ust b arriers. T h e 3D CAD m odel inc l udes w al l s, f l oors, m aj or eq uip m ent, struc tural sup p orts, and p ip es. Coated item s not inc l uded in th e 3D CAD m odel ( e.g., m isc el l aneous steel s suc h as grating, m inor eq uip m ent, and val ves) are c onsidered in c al c ul ating val ue w ith saf ety f ac tor in th e c oated surf ac e area.

Figures B .1-1 th rough B .1-3 sh ow sec tional view s of th e Z OI f or eac h b reak l oc ation.

KEPCO & KHNP B 5

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e B .1-1 Destruc tion Pressures and Assoc iated Z OI Radii f or M aterial s f rom T ab l e 3-2 of th e SE of NEI 04-07 ( Ref erenc e [ 1-2] )

Destruc tion Pressure Z OI Radius/

Insul ation T y p es

( p sig) B reak Diam eter Protec tive c oating T B D( 1) NA( 2)

( ep ox y and ep ox y -p h enol ic p aints)

Protec tive c oatings T B D( 1) NA( 2)

( untop c oated inorganic z inc )

T ransc o RM I 114 2.0 Darc h em DARM ET J ac k ed NU KON w ith Sure-Hol d b ands 90 2.4 M inor w ith Sure-Hol d b ands K-w ool 24 5.4 Cal -Sil ( Al . c l adding, SS b ands) 24 5.45 T em p -M at w ith 10.2 11.7 stainl ess steel w rite retainer U nj ac k eted NU KON, J ac k eted NU KON 6 17.0 w ith standard b ands Knaup f ET p anel Kool p h en-K 3.6 22.9 M in-K 2.4 28.6 M irror w ith standard b ands Note :

( 1) T o b e determ ined ex p erim ental l y

( 2) Not avail ab l e f or eval uation at th is tim e KEPCO & KHNP B 6

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.2 EVALUATION OF INSULATION DEBRIS GENERATION As desc rib ed in Sec tion 2.5 of th e m ain b ody of th is tec h nic al rep ort, RM I is th e onl y insul ation used f or eq uip m ent and p ip ing in c ontainm ent. For RM I deb ris generation, th e diam eter of th e Z OI is def ined as 2 inside diam eters ( IDs) of th e b rok en p ip e b ased on th e ap p roved m eth odol ogy , th e SE f or NEI 04-07

( Ref erenc e [ 1-2] ) .

T h e Z OI f or RM I is ap p l ied using th e c riteria in T ab l e 3-2 of th e SE of NEI 04-07 ( Ref erenc e [ 1-2] ) .

rIZOI

= 2 ------------------------------------------------------------------------------------------------------- ( 1)

DBREAK W h ere, rIZ OI = sp h eric al Z OI radius f or RM I DB REAK = ID of b reak p ip e TS RM I th ic k ness th at is used is b ased on Ref erenc e [ 2-1] .

Figures B .2-1, B .2-2, and B .2-3 sh ow a sp h eric al region w ith in a distanc e eq ual to 2 IDs of th e b rok en p ip e w h en th e j unc tions of th e reac tor c ool ant sy stem ( RCS) h ot l eg l ine ( 42 inc h ) , RCS c ol d l eg l ine ( 30 inc h ) ,

and m ain steam l ine of th e steam generator ( SG) are b rok en.

B.2.1 Insulation Deb ris G eneration f rom an RCS H ot Leg Line Break (42 inches)

U sing Eq uation ( 1) , th e radius of th e sp h eric al Z OI f or RM I is c al c ul ated as 7 f t.

T h e b oundary of th e Z OI is sh ow n in Figures B .1-1 and B .2-1, and ex tends f rom th e c enter of th e b reak to th e p rim ary sh iel d w al l on th e righ t side, a p ortion of th e SG No. 2 on th e l ef t side, a p ortion of SG No. 2 on th e up p er side, and a p ortion of th e p edestal of SG No. 2 on th e l ow er side.

Surf ac e areas f or sep arate p arts are sh ow n in Figure B .2-4 and c al c ul ated in T ab l e B .2-1.

KEPCO & KHNP B 7

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e B .2-1 RM I Generated f rom an RCS Hot L eg L ine B reak Part Surf ac e Area 3 Area 2 V ol um e ( f t )

No. (ft)

Noz z l e ( AN) 1 Hot L eg L ine Pip e ( AP) 2 Surge/ SC L ine ( AS) 3 Steam Generator L ow er Sh el l ( AD) 4 Steam Generator Sk irt ( AK) 5 T otal TS B.2.2 Insulation Deb ris G eneration f rom an RCS Cold Leg Line Break (30 inches)

U sing Eq uation ( 1) , th e radius of th e sp h eric al Z OI f or RM I is c al c ul ated as 5 f t.

T h e b oundary of th e Z OI is sh ow n in Figures B .1-2 and B .2-2. Surf ac e areas f or sep arate p arts are sh ow n on Figure B .2-5 and c al c ul ated in T ab l e 2-2.

T ab l e B .2-2 RM I Generated f rom an RCS Col d L eg L ine B reak Part Surf ac e Area 3 Area 2 V ol um e ( f t )

No. (ft)

Noz z l e ( AN) 1 Col d L eg L ine Pip e ( AP) 2 Steam Generator L ow er Sh el l ( AD) 3 Steam Generator Sk irt ( AK) 4 T otal TS KEPCO & KHNP B 8

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.2.3 Insulation Deb ris G eneration f rom a M ain Steam Line Break (30.907 inches)

U sing Eq uation ( 1) , th e radius of th e sp h eric al Z OI f or RM I is c al c ul ated as 5.2 f t.

T h e b oundary of th e Z OI is sh ow n in Figures B .1-3 and B .2-3. Surf ac e areas f or sep arate p arts are sh ow n on Figure B .2-6 and c al c ul ated in T ab l e 2-3.

T ab l e B 2-3 RM I Generated f rom a M ain Steam L ine B reak Part Surf ac e Area 3 Area 2 V ol um e ( f t )

No. (ft)

Noz z l e ( AN) 1 M ain Steam L ine Pip e ( AP) 2 Steam Generator L ow er Sh el l ( AD) 3 T otal TS KEPCO & KHNP B 9

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.3 EVALUATION OF COATING DEBRIS GENERATION As desc rib ed in Sec tions 3.4.3.3.3 and 3.4.3.3.4 of NEI 04-07 ( Ref erenc e [ 1-1] ) , q ual if ied and unq ual if ied c oatings w ith in th e c oating Z OI are assum ed to f ail and al l q ual if ied c oatings l oc ated outside th e c oating Z OI are c onsidered not to f ail w h en sub j ec ted to c ontainm ent sp ray or im m ersed in th e p ost-DB A p ool .

Al l c oatings used on struc tures, sy stem , and c om p onents w ith in c ontainm ent in th e APR1400 are q ual if ied c oatings, w h ic h are a DB A-q ual if ied and ac c ep tab l e c oating sy stem as desc rib ed in Sec tion 2.6 of m ain b ody of th is tec h nic al rep ort.

B ased on Ref erenc e [ 3-1] , th e Z OI f or q ual if ied ep ox y c oatings is a sp h ere w ith a radius 4 tim es th e b reak p ip e inner diam eter ( 4D) , and th e Z OI f or untop c oated inorganic z inc ( IOZ ) c oatings inside c ontainm ent use a sp h ere w ith radius 10 tim es th e b reak p ip e inner diam eter ( 10D) . T h e vol um e of c oating deb ris is c al c ul ated b y m ul tip l y ing th e surf ac e area of th e Z OI sp h ere b y th e th ic k ness of th e c oating f il m .

U ntop c oated IOZ c oatings are used onl y f or eq uip m ent ( reac tor c ool ant p um p ( RCP) and RCP m otor) and sup p orts ( SG, RCP, and surge l ine) in th e 10D Z OI of th e RCS h ot l eg l ine b reak and c ol d l eg l ine b reak .

In addition, th ere is no untop c oated IOZ c oating in th e 10D Z OI of th e m ain steam l ine b reak .

T h e c oating th ic k ness b ased on th e data sh ow n in T ab l e B .3-1 and eval uated f or th e APR1400 is used in th e eval uation of c oating deb ris generation w ith c onservatism .

KEPCO & KHNP B 10

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e B .3-1 Coating M aterial s and Coating T h ic k ness inside Containm ent Coating Ap p l ic ation Coating Sy stem T h ic k ness ( m il s)

Inorganic Z inc p rim er 3.0 ~ 5.0 Containm ent L iner Pl ate, Struc tural Steel Ep ox y Finish 3.0 ~ 5.0 Eq uip m ent and Com p onent Ep ox y Prim er 3.0 ~ 5.0 o

( l ess th an 200 F)

Ep ox y Finish 3.0 ~ 5.0 Eq uip m ent and Com p onent o o ( 1) Inorganic Z inc p rim er 3.0 ~ 5.0

( 200 F to 750 F)

Ep ox y Prim er 0.3 ~ 1.0 W al l and Ceil ing Conc rete Ep ox y Interm ediate 10.0 ~ 15.0 Ep ox y Finish 5.0 ~ 9.0 Ep ox y Prim er 0.3 ~ 1.0 Fl oor Conc rete Ep ox y Interm ediate 20.0 ~ 27.0 Ep ox y Finish 6.0 ~ 8.0 Note :

( 1) Eval uation eq uip m ent and c om p onents in th e 10D Z OI of th e RCS h ot/ c ol d l eg l ine and m ain steam l ine b reak are, f or ex am p l e, RCP, RCP m otor, and sup p orts ( RCP, SG, and surge l ine) .

Coating deb ris generation is al so eval uated using th e CAD m odel devel op ed as a p art of th e in-c ontainm ent ref uel ing w ater storage tank ( IRW ST ) sum p anal y sis and an estim ate of th e total c onc rete and steel surf ac e area w ith in th e Z OI. T h is m eth odol ogy is th e sam e as m eth odol ogy th at is used to eval uate insul ation deb ris generation. T h e 4D of th e Z OI f or ep ox y and th e 10D f or th e IOZ are used to determ ine a surf ac e area. Credit is tak en in a c onservative m anner f or som e areas sh iel ded b y rob ust b arriers. T h e 3D view f or th e D-ring of th e Steam Generator No.2 c om p artm ent is sh ow n in Figure B .3-1.

KEPCO & KHNP B 11

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.3.1 Coating Deb ris G eneration f rom an RCS H ot Leg Line Break (42 inches)

U sing Eq uation ( 1) , th e 4D and 10D radii of th e sp h eric al Z OI are c al c ul ated as 14 f t and 35 f t, resp ec tivel y .

T h e b oundary of th e Z OI is sh ow n in Figures B .1-1, B .3-2, and B .3-3. Surf ac e areas f or sep arate p arts of ep ox y c oating and untop c oated IOZ p arts are sh ow n in Figures B .3-4 and B .3-5, and c al c ul ated in T ab l es B .3-2 and B .3-3, resp ec tivel y .

T ab l e B .3-2 Ep ox y Coating ( 4D) Generated f rom an RCS Hot L eg L ine B reak Part Surf ac e Area T h ic k ness V ol um e Area 2 3 No. (ft) ( m il s) (ft) 1 470.09 25 0.98 W al l Surf ac e f or D-Ring 2 14.07 25 0.03 of SG Com p artm ent 3 14.07 25 0.03 4 145.07 25 0.30 5 38.52 25 0.08 SG Pedestal W al l Surf ac e 6 38.52 25 0.08 7 92.81 25 0.19 M isc el l aneous Steel s - 300 5 0.12 T otal 1.82 T ab l e B .3-3 IOZ Coating ( 10D) Generated f rom an RCS Hot L eg L ine B reak Surf ac e Area T h ic k ness V ol um e Area 2 3 (ft) ( m il s) (ft)

RCP M otor Pedestal 1140.97 5 0.48 RCP Casing Cover 139.93 5 0.06 RCP Sup p orts 631.63 5 0.26 SG Sup p ort 492.77 5 0.21 Surge L ine Sup p orts 200.00 5 0.08 M isc el l aneous Steel s 300 5 0.12 T otal 1.21 KEPCO & KHNP B 12

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.3.2 Coating Deb ris G eneration f rom an RCS Cold Leg Line Break (30 inch)

U sing Eq uation ( 1) , th e 4D and 10D radii of th e sp h eric al Z OI are c al c ul ated as 10 f t and 25 f t, resp ec tivel y .

T h e b oundary of th e Z OI is sh ow n in Figures B .1-2, B .3-6, and B .3-7. Surf ac e areas f or sep arate p arts of ep ox y c oating and untop c oated IOZ p arts are sh ow n in Figures B .3-8 and B .3-9, and c al c ul ated in T ab l es B .3-4 and B .3-5, resp ec tivel y .

T ab l e B .3-4 Ep ox y Coating ( 4D) Generated f rom an RCS Col d L eg L ine B reak Part Surf ac e Area T h ic k ness V ol um e Area 2 3 No. (ft) ( m il s) (ft) 1 1.33 25 0.00 2 7.32 25 0.02 SG Pedestal W al l Surf ac e 3 13.15 25 0.03 4 4.81 25 0.01 M isc el l aneous Steel s - 300 5 0.12 T otal 0.18 T ab l e B .3-5 IOZ Coating ( 10D) Generated f rom an RCS Col d L eg L ine B reak Surf ac e Area T h ic k ness V ol um e Area 2 3 (ft) ( m il s) (ft)

RCP M otor Pedestal 1140.97 5 0.48 RCP Casing Cover 139.93 5 0.06 RCP Sup p orts 631.63 5 0.26 SG Sup p ort 492.77 5 0.21 Surge L ine Sup p orts 200.00 5 0.08 M isc el l aneous Steel s 300 5 0.12 T otal 1.21 KEPCO & KHNP B 13

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.3.3 Coating Deb ris G eneration f rom a M ain Steam Line Break (30.907 inches)

U sing Eq uation ( 1) , th e 4D and 10D radii of th e sp h eric al Z OI are c al c ul ated as 10.4 f t and 26 f t, resp ec tivel y .

T h e b oundary of th e Z OI is sh ow n in Figures B .1-3, B .3-10, and B .3-11. Surf ac e areas f or sep arate p arts of ep ox y c oating and untop c oated IOZ p arts are sh ow n in Figures B .3-12 and B .3-13, and c al c ul ated in T ab l es B .3-6 and B .3-7, resp ec tivel y .

T ab l e B .3-6 Ep ox y Coating ( 4D) Generated f rom a M ain Steam L ine B reak Surf ac e Area T h ic k ness V ol um e Area 2 3 (ft) ( m il s) (ft)

M isc el l aneous Steel s 500 5 0.21 T otal 0.21 T ab l e B .3-7 IOZ ( 10D) Generated f rom a M ain Steam L ine B reak Surf ac e Area T h ic k ness V ol um e Area 2 3 (ft) ( m il s) (ft)

M isc el l aneous Steel s 500 5 0.21 T otal 0.21 KEPCO & KHNP B 14

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.4 EVALUATION OF LATENT DEBRIS GENERATION L atent deb ris is def ined as unintended dirt, p aint c h ip s, and f ib er, w h ic h c onsist p rinc ip al l y of f ib er and p artic l e deb ris.

T h e q uantity and ty p e of l atent deb ris is usual l y determ ined b ased on w al k dow n data, b ut w al k dow n data c annot b e used b ec ause th e APR1400 p l ant is a c onstruc tion p l ant. A rec ent sam p l ing of surf ac es inside c ontainm ent at a num b er of p l ants in th e U nited States indic ate th at it is l ik el y th at th e m ax im um m ass of l atent deb ris inside c ontainm ent is l ess th an 200 l b m ( Ref erenc e [ 1-1] ) . T h is val ue ( 200 l b m ) is th eref ore suf f ic ient f or a c onservative eval uation of th e q uantity of deb ris.

KEPCO & KHNP B 15

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.5 CONCLUSION T h e total am ount of insul ation, c oating and l atent deb ris f or eac h b reak l oc ation, b ased on th e resul ts of th e eval uation, is sum m ariz ed in T ab l e B .5-1.

T ab l e B .5-1 Deb ris Generation f or Eac h B reak L oc ation B reak L oc ation RCS Hot L eg L ine RCS Col d l eg L ine M ain Steam L ine Item NEI 04-07 NEI 04-07 NEI 04-07 Ap p l ic ab l e M eth odol ogy and SE and SE and SE B reak Siz e ( c m / inc h ) 106.7 / 42 76.2 / 30 78.5 / 30.907 Insul ation ( 2D) 2.13 / 7 1.52 / 5 1.58 / 5.2 Siz e of Z OI

( m / f t) Coating

- 4D ( Ep ox y ) 4.27 / 14 3.05 / 10 3.17 / 10.4

- 10D ( IOZ ) 10.67 / 35 7.62 / 25 7.92 / 26 TS RM I Insul ation 3 3 (m / ft) 3 3 ( 1)

Coating ( m / f t ) 0.086 / 3.03 0.039 / 1.39 0.012 / 0.42 Am ount - 4D ( Ep ox y ) 0.052 / 1.82 0.005 / 0.18 0.006 / 0.21

- 10D ( IOZ ) 0.034 / 1.21 0.034 / 1.21 0.006 / 0.21 L atent Deb ris 90.72 / 200 90.72 / 200 90.72 / 200

( k g/ lb m )

Note :

3

( 1) For strainer design, ep ox y c oating of 3.10 f t is c onservativel y used.

From th e T ab l e B .5-1, th e b reak l oc ation of th e j unc tion of b etw een th e RCS h ot l eg p ip e ( 42 inc h es) and th e SG is sel ec ted as th e w orst c ase f or generating m ax im um deb ris l oads. T h is b reak l oc ation is reasonab l e b ec ause th e SGs h ave a l arger vol um e of deb ris ap p l ied to th em th an th e RCS p ip ing and b ec ause m ost of th e p rim ary sy stem p ip ing is l oc ated in th e SG c om p artm ent. T h e m ore th e deb ris p resents, th e greater th e vol um e of deb ris is transp orted to th e sum p strainer. T h eref ore, th is b reak l oc ation resul ts in th e m ax im um h ead l oss ac ross th e sum p strainer.

KEPCO & KHNP B 16

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 B.6 REFERENCES 1-1 NEI 04-07, " Pressuriz ed W ater Reac tor Sum p Perf orm anc e Eval uation M eth odol ogy ," Nuc l ear Energy Institute, M ay 2004.

1-2 Saf ety Eval uation b y th e Of f ic e of Nuc l ear Reac tor Regul ation Rel ated to NRC Generic L etter 2004-02, Nuc l ear Energy Institute Guidanc e Rep ort ( Prop osed Doc um ent Num b er NEI 04-07) ,

" Pressuriz ed W ater Reac tor Sum p Perf orm anc e Eval uation M eth odol ogy ," Nuc l ear Energy Institute, Dec em b er 2004.

2-1 " Detail ed Heat L oss Cal c ul ation f or th e Reac tor V essel Insul ation at Sh in-Kori Nuc l ear Pow er Pl ant 3&4" ( SKN 3&4 PNS No.: 9-113-Z -301-001C) , Doosan Heavy Industries & Construc tion Co.,

L td., J anuary 2011.

3-1 NRC L etter to NEI, " Revised guidanc e regarding c oatings z one of inf l uenc e f or review of f inal l ic ensee resp onses to Generic L etter 2004-02, Potential Im p ac t of Design B asis Ac c idents at Pressuriz ed W ater Reac tors," U .S. Nuc l ear Regul atory Com m ission, Ap ril 2010.

KEPCO & KHNP B 17

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.1-1 Sectional V iew of Z OI f or an RCS H ot Leg Line Break (2D f or RM I; 4D and 10D f or Coating)

KEPCO & KHNP B 18

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.1-2 Sectional V iew of Z OI f or an RCS Cold Leg Line Break (2D f or RM I; 4D and 10D f or Coating)

KEPCO & KHNP B 19

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.1-3 Sectional V iew of Z OI f or a M ain Steam Line Break (2D f or RM I; 4D and 10D f or Coating)

KEPCO & KHNP B 20

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.2-1 3D M odel V iew of 2D Z OI f or an RCS H ot Leg Line Break KEPCO & KHNP B 21

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.2-2 3D M odel V iew of 2D Z OI f or an RCS Cold Leg Line Break KEPCO & KHNP B 22

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.2-3 3D M odel V iew of 2D Z OI f or a M ain Steam Line Break KEPCO & KHNP B 23

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure B.2-4 Separate Parts of Surf ace Areas f or an RCS H ot Leg Line Break (2D Z OI)

KEPCO & KHNP B 24

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure B.2-5 Separate Parts of Surf ace Areas f or an RCS Cold Leg Line Break (2D Z OI)

KEPCO & KHNP B 25

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure B.2-6 Separate Parts of Surf ace Areas f or a M ain Steam Line Break (2D Z OI)

KEPCO & KHNP B 26

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-1 3D M odel V iew of the D-Ring of Steam G enerator No.2 Compartment KEPCO & KHNP B 27

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-2 3D M odel V iew of 4D Z OI f or an RCS H ot Leg Line Break KEPCO & KHNP B 28

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-3 3D M odel V iew of 10D Z OI f or an RCS H ot Leg Line Break KEPCO & KHNP B 29

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure B.3-4 Separate Parts of Surf ace Areas f or an RCS H ot Leg Line Break (4D Z OI)

KEPCO & KHNP B 30

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-5 3D M odel V iew of Surf ace Areas f or an RCS H ot Leg Line Break (10D Z OI)

KEPCO & KHNP B 31

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-6 3D M odel V iew of 4D Z OI f or an RCS Cold Leg Line Break KEPCO & KHNP B 32

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-7 3D M odel V iew of 10D Z OI f or an RCS Cold Leg Line Break KEPCO & KHNP B 33

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure B.3-8 Separate Parts of Surf ace Areas f or an RCS Cold Leg Line Break (4D Z OI)

KEPCO & KHNP B 34

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-9 3D M odel V iew of Surf ace Areas f or an RCS Cold Leg Line Break (10D Z OI)

KEPCO & KHNP B 35

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-10 3D M odel V iew of 4D Z OI f or a M ain Steam Line Break KEPCO & KHNP B 36

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure B.3-11 3D M odel V iew of 10D Z OI f or a M ain Steam Line Break KEPCO & KHNP B 37

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure B.3-12 Separate Parts of Surf ace Areas f or a M ain Steam Line Break (4D Z OI)

KEPCO & KHNP B 38

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure B.3-13 3D M odel V iew of Surf ace Areas f or a M ain Steam Line Break (10D Z OI)

KEPCO & KHNP B 39

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix C Head Loss Test Report for the IRWST Sump Strainer KEPCO & KHNP C1

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TABLE OF CONTENTS C.1 INTRODUCTION ...................................................................................................... 6 C.2 TEST FACILITY DESCRIPTION ............................................................................... 7 C.2.1 Fl ow L oop ......................................................................................................................................... 7 C.2.2 Instrum entation ................................................................................................................................. 7 C.3 TEST PROTOTYPE .................................................................................................. 8 C.4 DEBRIS DESCRIPTION ........................................................................................... 8 C.4.1 L atent Fib er ....................................................................................................................................... 8 C.4.2 Sil ic on Carb ide .................................................................................................................................. 8 C.4.3 PW R Sand M ix ................................................................................................................................. 8 C.4.4 Al um inum Ox y -h y drox ide.................................................................................................................. 9 C.5 TEST PROCEDURE

SUMMARY

............................................................................. 10 C.5.1 Deb ris Prep aration .......................................................................................................................... 10 C.5.1.1 Particulate Preparation................................................................................................................................................ 10 C.5.1.2 Fiber Preparation ........................................................................................................................................................... 10 C.5.1.3 Aluminum Oxy-hydroxide Preparation ................................................................................................................ 10 C.5.2 T est Setup ........................................................................................................................................ 11 C.5.3 T est Initiation .................................................................................................................................... 11 C.5.4 Deb ris Addition ................................................................................................................................. 11 C.5.5 T est T erm ination ............................................................................................................................... 11 C.5.6 Post T est Ob servations .................................................................................................................... 11 C.5.6.1 Test APR1400-HL-0813-1........................................................................................................................................... 11 C.5.6.2 Test APR1400-HL-0913-2........................................................................................................................................... 12 C.5.6.3 Test Discrepancies and Nonconformances........................................................................................................ 12 C.6 RESULTS OF TESTING ......................................................................................... 13 C.6.1 Cl ean Fl ow Sw eep s ........................................................................................................................ 13 C.6.2 T est Conditions ............................................................................................................................... 13 C.6.3 APR1400-HL -0813-1 Deb ris Head L oss Resul ts ........................................................................... 15 C.6.4 APR1400-HL -0913-2 Deb ris Head L oss Resul ts ........................................................................... 15 C.6.5 V ortex T ests .................................................................................................................................... 16 KEPCO & KHNP C

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.7 QUALITY ASSURANCE ......................................................................................... 16 C.8 CONCLUSION ....................................................................................................... 17 C.9 REFERENCES ....................................................................................................... 18 KEPCO & KHNP C

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF TABLES T ab l e C.4-1 T arget Siz e Distrib ution ( Ref erenc e [ 1-1] and [ 1-2] ) ............................................................ 9 T ab l e C.6-1 Cl ean Fl ow Sw eep Resul ts ................................................................................................ 13 T ab l e C.6-2 Com p arison of Head L oss T est Conditions........................................................................ 13 T ab l e C.6-3 T est M atrix f or APR1400-HL -0813-1 .................................................................................. 14 T ab l e C.6-4 T est M atrix f or APR1400-HL -0913-2 .................................................................................. 14 T ab l e C.6-5 Head L oss T est Resul ts f or APR1400-HL -0813-1 ............................................................. 15 T ab l e C.6-6 Head L oss T est Resul ts f or APR1400-HL -0913-2 ............................................................. 15 T ab l e C.8-1 Final Head L oss T est Resul ts ............................................................................................ 17 KEPCO & KHNP C

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF FIGURES Figure C.2-1 Prototy p e Strainer in th e T est T ank .................................................................................... 19 Figure C.2-2 Pum p ( on l ef t) , and Data Ac q uisition Fl ow M eter/ DP Cel l s ( on righ t) ................................ 20 Figure C.2-3 Fl ow Sc h em atic of T est Setup ........................................................................................... 21 Figure C.3-1 T est Strainer Draw ing ........................................................................................................ 22 Figure C.4-1 Aged Fib er Sam p l e ............................................................................................................ 23 Figure C.4-2 Fib er U sed in APR1400-HL -0813-1 ................................................................................... 24 Figure C.4-3 Fib er U sed in APR1400-HL -0913-2 ................................................................................... 25 Figure C.4-4 M easured Siz e Distrib ution of B l ac k Sil ic on Carb ide......................................................... 26 Figure C.5-1 T y p ic al Partic ul ate Addition ( Sil ic on Carb ide on L ef t, Sand M ix ture on Righ t) .................. 27 Figure C.5-2 T y p ic al Fib er Fines Addition f or APR1400-HL -0813-1 ....................................................... 28 Figure C.5-3 T y p ic al Fib er Fines Addition f or APR1400-HL -0913-2 ....................................................... 29 Figure C.5-4 T y p ic al Ch em ic al Deb ris Addition ...................................................................................... 30 Figure C.5-5 T est Fac il ity L ay out ............................................................................................................ 31 Figure C.5-6 Post-test During Draining ( Suc tion Pip e is at T op of Ph oto) .............................................. 32 Figure C.5-7 Post-test During Draining ( Suc tion Pip e is at Righ t) .......................................................... 33 Figure C.5-8 Post-test During Draining ( L ef t and Righ t Sides of th e Strainer) ....................................... 34 Figure C.5-9 Cy l inders B ottom L ef t Side of Strainer Sh ow ing Deb ris Having Fal l en Of f Strainer

( Aw ay From ( on top ) and Near ( on b ottom ) Suc tion Pip e) ................................................ 35 Figure C.5-10 T y p ic al V iew Inside Strainer T ub es Af ter Drain Dow n ....................................................... 36 Figure C.5-11 L ef t Side of Strainer During Drain Dow n ( Suc tion Pip e is on Righ t of Ph oto) ................... 37 Figure C.5-12 Com p arison of L ef t and Righ t Side of th e Strainer Af ter Drain Dow n................................ 38 Figure C.5-13 Com p arison of Ends of th e Strainer Af ter Drain Dow n ...................................................... 39 Figure C.5-14 T y p ic al V iew Inside of Strainer T ub es Af ter Drain Dow n ................................................... 40 Figure C.6-1 Cl ean Fl ow Sw eep Data .................................................................................................... 41 Figure C.6-2 T im e Histories of Head L oss, Fl ow Rate, and T em p erature ( APR1400-HL -0813-1) ......... 42 Figure C.6-3 T im e Histories of Head L oss, Fl ow Rate, and T em p erature ( APR1400-HL -0913-2) ......... 43 Figure C.6-4 V ortex Identif ic ation During APR1400-HL -0813-1 ( on l ef t) and APR1400-HL -0913-2 ( on righ t) .......................................................................................... 44 KEPCO & KHNP C

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.1 INTRODUCTION If a l oss of c ool ant ac c ident ( L OCA) w ere to oc c ur, it is p ostul ated th at th is L OCA c oul d generate and transp ort deb ris to th e IRW ST sum p strainer. T h e deb ris th at c oul d ac c um ul ate on th e strainer m ay f orm a deb ris b ed and inc rease th e h ead l os ac ross th e strainer. T h e p urp ose of th ese tests is to devel op data to val idate th e IRW ST sum p strainer p erf orm anc e using c onservative assum p tions. Fl ow sw eep s w ere al so c onduc ted to adj ust th e h ead l oss over th e range of f l uid tem p eratures req uired f or th e strainer op eration. Ac c ep tanc e eval uation w il l b e p erf orm ed sep aratel y f rom th is rep ort.

T h e tests w ere c onduc ted f ol l ow ing test p l ans ( Ref erenc e [ 1-1] and [ 1-2] ) devel op ed b y Struc tural Integrity Assoc iates. T h e p rinc ip al dif f erenc e b etw een th e tests w as th at th e f irst test w as b ased on a p l ant 2 2 2 strainer area of 55.74 m ( 600 f t² ) and th e sec ond test w as b ased on a strainer area of 46.45 m ( 500 f t ) ,

2 2 9.29 m ( 100 f t ) w as assum ed b l oc k ed b y tags ( Ref erenc e [ 1-1] and [ 1-2] ) .

KEPCO & KHNP C6

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.2 TEST FACILITY DESCRIPTION C.2.1 Flow Loop T h e test f ac il ity c onsists of an ap p rox im atel y 4.57 m ( 15 f t) diam eter tank th at is 2.13 m ( 7 f t) deep . T h e f l ow returns into th e tank f rom a 6 inc h p ip e w ith a tee th at is p ointed at th e f l oor in th e c enter of th e tank .

T h e ex it of th e tee is ap p rox im atel y 0.05 m ( 2 inc h ) ab ove th e f l oor so th at th e return f l ow sw eep s al ong 3

th e f l oor th en up th e tank w al l s to h el p susp end deb ris. T h e tank c an h ol d ap p rox im atel y 35.96 m ( 9500 gal l ons) of w ater.

T h e test strainer is l oc ated nex t to th e return p ip e w ith th e strainer p l enum m ounted 0.15 m ( 6 inc h ) ab ove th e tank f l oor. T h e top of th e strainer el em ents are 1.19 m ( 46.75 inc h ) ab ove th e tank f l oor. Six agitators ( trol l ing m otors) are l oc ated at ap p rox im atel y every 60 degrees at an ap p rox im atel y 3.66 m ( 12 f t) diam eter ( see Figure C.2-1) .

T h e suc tion p ip e is attac h ed to th e strainer and runs to th e Godw in CD150M p um p . T h e disc h arge of th e p um p goes to a f l ow m eter, f l ow c ontrol val ve, and th en b ac k into th e tank ( see Figure C.2-2, and Figure C.2-3 f or a sc h em atic ) .

Fl ow rate c an b e c ontrol l ed b y a c om b ination of a variab l e f req uenc y drive ( V FD) th at drives th e p um p , th e gate val ve, or a b y p ass l ine w h ic h p rovides a sh ort c irc uit p ath b etw een th e suc tion and disc h arge of th e p um p . T y p ic al l y , th e V FD is used to c ontrol th e f l ow rate during a test, unl ess very l ow f l ow rates need to b e ac h ieved.

C.2.2 Instrumentation Head l oss ac ross th e strainer w as m easured b y tw o indep endent Rosem ount m odel 1151 dif f erential p ressure transduc ers. One transduc er w as sc al ed to 0-100 in of w ater and th e sec ond w as sc al ed to 0 -

7.62 m ( 0 - 300 inc h ) of w ater. T h ese transduc ers w ere c al ib rated to + / -0.125% of th eir range. T h e l ow side of th e dif f erential p ressure transduc er w as c onnec ted to th e p ressure tap on th e strainer p l enum and th e h igh side of th e p ressure transduc ers w as c onnec ted to a tap on th e tank w al l .

Fl ow rate w as m easured b y a six -inc h Om ega m odel M G1000 el ec trom agnetic f l ow m eter. T h e f l ow m eter w as instal l ed on th e disc h arge side of th e p um p m ore th an 50 diam eters up stream of th e p um p w ith a straigh t sec tion of p ip e up stream and dow nstream of th e f l ow m eter. A f l ow c ontrol val ve w as instal l ed dow nstream of th e straigh t sec tion of p ip ing.

W ater tem p erature w as m easured w ith a ty p e T th erm oc oup l e instal l ed in th e tank near th e w ater surf ac e.

T h e th erm oc oup l e w as c onnec ted to an Om ega DP-41 T C-A p roc ess m eter.

Al l of th ese instrum ents w ere c onnec ted to a Dataq DI-220 data ac q uisition sy stem running L SP60 sof tw are. T h is sof tw are rec ords data every tw o sec onds to disk in tab del im ited f orm at in engineering units. T h e sof tw are al so p rovides p l otting and digital disp l ay s of al l of th e instrum entation b eing rec orded.

KEPCO & KHNP C7

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.3 TEST PROTOTYPE A p rototy p e T ransc o strainer w as tested ( see Figures C.2-1 and C.3-1) . T h e strainer c onsists of th ree strainer c artridges eac h w ith f our tub es b ol ted to a p l enum th at al l ow s a f l ow p ath f rom eac h tub e to th e p um p suc tion p ip e. T h e th ree c artridges w ere l ab el l ed as C4570-004, C4570-005, and C4570-006. T h e 2 2 surf ac e area of th is c onf iguration is 6.97 m ( 75.1 f t ) w ith p erf orated p l ate h ol e siz e of 2.38 m m ( 0.094 inc h ) in Ref erenc e [ 1-1] . T h e p l enum w as m ounted 0.15 m ( 6 inc h ) ab ove th e tank f l oor.

C.4 DEBRIS DESCRIPTION Four ty p es of deb ris w ere used in th e test. Aged Nuk on f ib ergl ass w as p rep ared as f ines to sim ul ate l atent f ib er, sil ic on c arb ide to sim ul ate ep ox y p aint, sand m ix ture to sim ul ate l atent p artic ul ate, and al um inum ox y -h y drox ide to sim ul ate c h em ic al deb ris ( Ref erenc e [ 1-1] and [ 1-2] ) .

C.4.1 Latent Fib er For th is test f ib er, f ines w ere tested to sim ul ate l atent deb ris. Fib er w as p rep ared f rom aged Nuk on f ib ergl ass. T h e f ib ergl ass w as ob tained h eat treated f rom Perf orm anc e Contrac ting Inc . l ot num b er J -

006-12HT

• L N-1840. T h e h eat treating p roc ess f ol l ow ed PCI p roc edure DPP-01 w h ic h h eated one side of th e insul ation on a h ot p l ate at 300 ° C ( 572 ° F) f or 6 to 8 h ours. T h e rec eived insul ation w as insp ec ted visual l y to c onf irm th at th e h eat treatm ent p roduc ed a c ol or gradient ap p rop riate f or aged f ib er ( see Figure C.4-1) .

T h e use of f ib ergl ass insul ation, suc h as Nuk on is rec om m ended as a surrogate f or dry l atent deb ris

( Ref erenc e [ 4-1] ) . T h e f ib er w as p roc essed into f ines. For test APR1400-HL -0813-1, th e f ib er w as sh redded onc e, th en sep arated b y a p ressure w ash er, and stirred w ith a m ix er. T y p ic al f ib er is sh ow n b el ow in Figure C.4-2. T h ese f ib ers h ave a signif ic ant am ount of c l ass 1 and 2 f ib ers, b ut al so signif ic ant am ount of c l ass 3 f ib ers as def ined in ( Ref erenc e [ 4-2] ) . For test APR1400-HL -0913-2, th e f ib ers w ere trip l e sh redded, sep arated b y a p ressure w ash er, and stirred b y a m ix er in a m ore dil ute f ib er w ater m ix ture. T h e susp ended f ib ers are sh ow n in Figure C.4-3 w h ic h are nearl y al l c l ass 1 and 2 ( Ref erenc e

[ 4-2] ) .

C.4.2 Silicon Carb ide El ec troCarb b l ac k sil ic on c arb ide ( siz e 800) w as ob tained f rom El ec tro Ab rasives in B uf f al o NY . T h ese

-4 p artic l es h ave an average diam eter of ap p rox im atel y 10 m ( 3.94x 10 inc h ) as m easured b y th e m anuf ac turer. A sam p l e of th e sil ic on c arb ide w as m ic rosc op ic al l y m easured and h ad an average

-4 diam eter of 8.64 m ( 3.40x 10 inc h ) ( Sh oem ak er, Kevin, M &P L ab Rep ort 0929, J anuary 13, 2009) .

C.4.3 PWR Sand M ix PW R sand m ix is def ined to h ave a target siz e distrib ution as sh ow n in T ab l e C.4-1. T h e PW R m ix w as m ade b y c om b ining th ree ty p es of sand. Paver l evel ing sand f rom Hom e Dep ot w as used f or th e c oarse

-2 sand. It w as p assed th rough a 2,000 m ( 7.87x 10 inc h ) sieve and no m aterial p assed th rough a 500

-2 m ( 1.97x 10 inc h ) sieve. Gl ass b ead b l asting m edia w as ob tained in tw o dif f erent siz e ranges f rom Potters Industries in Pottsdam , New Y ork ( th rough M c M aster Carr) . T h e siz e l ab el l ed 40-60 m esh , l ot

-2 num b er 1052713PO-2236 w as al l m edium c l assif ic ation, al l th e sand p assed th rough a 500 m ( 1.97x 10

-3 inc h ) sieve and did not p ass th rough a 75 m ( 2.95x 10 inc h ) sieve. T h e sec ond siz e w as l ab el l ed 170 -

325 m esh , l ot num b er 1072313PO-3118 and w as a c om b ination of f ine and m edium siz es. 75.94% of

-3 th e sand p assed th rough a 75 m ( 2.95x 10 inc h ) sieve ( f ine) and 24.06% p assed th rough a 500 m

-2 -3

( 1.97x 10 inc h ) sieve b ut w as c ap tured on th e 75 m ( 2.95x 10 inc h ) ( m edium ) . T o c reate th e sand m ix ture 28% of th e total am ount w as w eigh ed out f rom th e p aver sand. T o c reate th e f ine sand 48.7% of th e total am ount w as w eigh ed out of th e 170 - 325 m esh , w h ic h p roduc ed 37% f ines and 11.7% m edium .

KEPCO & KHNP C8

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T h e rest of th e m edium sand, 23.3% of th e total , w as w eigh ed f rom th e 40-60 m esh sand.

T ab l e C.4-1 T arget Siz e Distrib ution ( Ref erenc e [ 1-1] and [ 1-2] )

Sand Rec ip e T arget ( % ) Cl assif ic ation

-3

< 75 m ( 2.95x 10 inc h ) 37 Fine

-3

> 75 m ( 2.95x 10 inc h ) and

-2 35 M edium

< 500 m ( 1.97x 10 inc h )

-2

> 500 m ( 1.97x 10 inc h ) and

-2 28 Coarse

< 2,000 m ( 7.87x 10 inc h )

C.4.4 Aluminum Ox y-hydrox ide Al um inum Ox y -h y drox ide w as f ab ric ated f ol l ow ing W CAP-16530-NP-A and th e assoc iated saf ety eval uation ( Ref erenc e [ 4-3] and [ 4-4] ) . T h e c h em ic al s to m ak e th e al um inum ox y -h y drox ide, al um inum nitrate and sodium h y drox ide w ere ob tained f rom Fish er Sc ientif ic .

3 3 T h e al um inum ox y -h y drox ide w as m ade at a c onc entration of 0.011 g/ c m ( 0.69 l b m / f t ) im m ediatel y p rior to th e test and a settl ing test w as p erf orm ed to ensure th e c h em ic al surrogate m et th e req uirem ents in Ref erenc e [ 4-4] .

KEPCO & KHNP C9

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.5 TEST PROCEDURE

SUMMARY

C.5.1 Deb ris Preparation C.5.1.1 Particulate Preparation T h e p artic ul ate, sand m ix ture and sil ic on c arb ide, w as sp l it into b uc k ets w ith ap p rox im atel y 4.54 k g ( 10 3

l b m ) in eac h b uc k et. Ab out 0.011 m ( 3 gal l ons) of w ater w as c aref ul l y added to eac h b uc k et and th e m ix ture w as agitated w ith a p rop el l er agitator attac h ed to a dril l m otor. T h e p artic ul ate and w ater w as m ix ed to susp end th e deb ris to f ac il itate p ouring th e m ix ture into th e tank .

C.5.1.2 Fiber Preparation Fib er f ines w ere p rep ared b ased on NEI guidanc e ( Ref erenc e [ 5-1] ) . For b oth tests th e deb ris p rep aration w as sim il ar, b ut th e sec ond test ARPR1400-HL -0913-2 did additional sh redding and f ib er dil ution to ensure th e f ib er added to th e tank w as nearl y al l c l ass 1 and 2 ( Ref erenc e [ 4-2] ) and h ad no aggl om eration as it w as added.

For b oth tests, aged Nuk on f ib ergl ass insul ation w as c ut into ap p rox im atel y 7.62 c m b y 7.62 c m ( 3 inc h b y 3 inc h ) p iec es. T h e c ut p iec es w ere th en sh redded in a l eaf sh redder/ c h ip p er, sep arated b y a p ressure w ash er, p ut into b uc k ets, agitated b y a m ix er, and th en p oured into th e tank .

For test APR1400-HL -0813-1, th e f ib er w as sh red a singl e tim e. T h e f ib er w as w eigh ed into b atc h es of 3

0.43 k g ( 0.95 l b m ) . A b atc h of f ib er of 0.43 k g ( 0.95 l b m ) w as p l ac ed in 0.015 m ( 4 gal l ons) of w ater in a 3

0.121 m ( 32 gal l on) p l astic c ontainer. T h e f ib er w as th orough l y w et and th en sep arated using a p ressure w ash er w ith a f an noz z l e f or ap p rox im atel y 4 m inutes. T h e f ib er w as th en sep arated into b uc k ets. T h e f ib er w ater m ix ture w as th en agitated w ith a p rop el l er m ix er at h igh sp eed f or one m inute, and th e f ib er w ater m ix ture w as added to th e tank around th e p erim eter w h ere th e f l ow turb ul enc e and up w el l ing dil uted th e f ib er m ix ture ( See Figure C.4-2) . Ph otograp h s and video w ere tak en of th e f ib er addition ( f or ex am p l e see Figure C.5-2) .

For test APR1400-HL -0913-2, th e f ib er w as sh redded th ree tim es. T h e sh red f ib er w as th en w eigh ed into 2 b atc h es of 0.52 k g ( 1.15 l b m ) . A b atc h w as sp l it into th ree ap p rox im atel y eq ual p ortions and eac h 3 3 th ird w as p l ac ed into p l astic c ontainer ( ap p rox im atel y 0.121 m ( 32 gal l ons) ) w ith ap p rox im atel y 0.008 m

( 2 gal l ons) of w ater. T h e f ib er w as th orough l y w et. T h e f ib er w as th en sep arated using a p ressure w ash er w ith a f an noz z l e f or 4 m inutes. T h e w ater f ib er m ix ture w as th en f urth er dil uted into eigh t 0.019 3 3 m ( 5 gal l on) b uc k ets w ith a total of 0.011 m ( 3 gal l ons) of w ater in eac h b uc k et. Im m ediatel y p rior to adding th e f ib er, th e f ib er w as agitated w ith a p rop el l er m ix er on h igh f or one m inute. A sam p l e of th is f ib er w ater m ix ture w as tak en to ensure th e p roc ess p roduc ed f ines th at w ere nearl y al l c l ass 1 and 2 f ines

( Ref erenc e [ 4-2] ) ( see Figure C.4-3) . T h e f ib er m ix ture w as added to th e tank and th ere w ere no f ib er c l um p s as th e f ib er w as p oured into th e tank . Ph otograp h s and video w ere tak en of th e f ib er addition ( f or ex am p l e see Figure C.5-3) .

C.5.1.3 Aluminum Oxy-hydroxide Preparation Al um inum Ox y -h y drox ide ( AL OOH) is m ade f ol l ow ing th e W CAP-16350 rec ip e ( Ref erenc e [ 4-3] ) . Given 3

th e vol um e of AL OOH req uired th e am ount of w ater is determ ined f rom th e c onc entration ( 0.011 g/ c m 3

( 0.69 l b m / f t ) ) .

W ater is added to a c l ean p l astic tank . Al um inum nitrate nonah y drate is added sl ow l y to th e w ater at 6.25 l b / l b of AL OOH. T h e w ater is m ix ed b y a stirrer. Af ter th e al um inum nitrate h as al l dissol ved, sodium h y drox ide is added at 2.0 l b / l b of AL OOH. T h e susp ension m ust b e m ix ed f or at l east one h our.

A sam p l e is tak en and p l ac ed undisturb ed in a graduated c y l inder f or an h our to p erf orm a settl ing test.

KEPCO & KHNP C10

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Af ter one h our, greater th an 60% of th e vol um e m ust rem ain c l oudy .

T h e AL OOH is m ix ed in a p l astic tank . T h e req uired am ount of vol um e is w eigh ed out into p l astic c ontainers and p oured into th e tank around th e p erim eter.

C.5.2 T est Setup T h e test setup c onsisted of c l eaning th e f ac il ity and c l eaning and assem b l ing th e strainer as sh ow n in Figure C.2-1. T h e c onf iguration is sk etc h ed in Figure C.5-5. T h e strainer w as c h ec k ed to ensure th ere w ere no gap s greater th an 2.38 m m ( 0.094 inc h ) . T h e tank and p ip ing w ere f il l ed w ith w ater at 26.7 ° C

( 80 ° F) , th e m inim um tem p erature req uired in th e test p l an. T h e w ater l evel w as set at 24 in ab ove th e top of th e strainer tub es.

C.5.3 T est Initiation B oth tests w ere initiated b y c onduc ting a c l ean f l ow sw eep . B ec ause th ey h ad dif f erent target f l ow rates th e sw eep s oc c urred at sl igh tl y dif f erent target f l ow rates. Al l 6 agitators w ere on f or b oth tests.

C.5.4 Deb ris Addition Af ter th e c l ean f l ow sw eep s w ere c om p l eted, p artic ul ate w as added to th e tank . Partic ul ate w as 3

distrib uted into 0.019 m ( 5 gal l on) b uc k ets and m ix ed w ith w ater. T h e p artic ul ate w as added as sl urry to m ak e it easier to add th e p artic ul ate in th e tank . T h e b uc k ets w ere p oured around th e p erim eter of th e tank . For eac h test th ere w as a singl e addition of p artic ul ate, see Figure C.5-1 f or ty p ic al addition.

Several b uc k ets w ere added at c onsec utivel y to c om p l ete th e addition.

Af ter th e p artic ul ate w as al l ow ed to c irc ul ate f or a m inim um of 2 p ool turnover tim es ( PT Os) , th e f irst of tw o b atc h es of f ib er w ere added. Fib er w as added as sl urry around th e p erim eter of th e tank ( see Figures C.5-2 and C.5-3) . Several b uc k ets w ere added at c onsec utivel y to c om p l ete th e addition. T h e sec ond b atc h of f ib er w as added af ter 10 PT Os and th e h ead l oss reac h ed its stab il ity c riterion ( < 1%

h ead l oss c h ange in one h our) . T h e h ead l oss w as so l ow th at a 1% c h ange in one h our w as dif f ic ul t to determ ine, b ut th e h ead l oss essential l y rem ained c onstant to m eet th is c riterion.

3 Ch em ic al deb ris w as th en added f rom p l astic 0.114 m ( 30 gal l on) c ontainers and p oured around th e 3

p erim eter of th e tank . For test APR-HL -0813-1, th ree c h em ic al additions of 0.189 m ( 50 gal l ons) eac h w ere added. T h e h ead l oss did not inc rease f or th e l ast tw o additions so no m ore additions w ere req uired. For test APR-HL - 0913-2, th e m easured h ead l oss inc reased sl igh tl y f or th e f irst th ree c h em ic al additions so th e total l oad of c h em ic al s w as added in f ive b atc h es.

C.5.5 T est T ermination Eac h sub test w as term inated b y c om p l eting th e req uired m inim um tim e and reac h ing th e h ead l oss stab il ity req uirem ent, if ap p l ic ab l e. Cl ean f l ow sw eep s w ere c onduc ted f or th e tim e req uired and th en th at test w as term inated. Partic ul ate additions w ere c onduc ted f or th e tim e req uired and th en th at sub -

test w as term inated. Fib er and c h em ic al addition sub -tests w ere term inated up on c om p l eting at l east 10 PT Os and reac h ing h ead l oss stab il ity of < 1% / h our. Final f l ow sw eep s w ere term inated af ter c om p l eting th e req uired 2 PT Os at eac h f l ow rate.

C.5.6 Post T est Ob servations C.5.6.1 Test APR1400-HL-0813-1 Af ter th e test, th e suc tion and disc h arge vents w ere op ened very sl ow l y to m inim iz e disturb anc e of th e deb ris b ed. T y p ic al l y draining w ith h eavy deb ris b eds does disturb th e deb ris b ed b ec ause deb ris c an KEPCO & KHNP C11

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 easil y f al l of f vertic al surf ac es, esp ec ial l y w h en th ere is l ittl e h ead l oss ac ross th e deb ris b ed.

Figures C.5-6 and C.5-7 sh ow th at th e strainer in th e w ater w as b eing drained f rom th e tank . Som e op en area ap p ears to h ave rem ained during th e test. T h ere are areas w h ere deb ris h as f al l en of f th e strainer p erf orated p l ate al so. T h e deb ris b ed is th inner at th e top of th e strainer el em ents. B oth p h otos sh ow eac h strainer el em ent c overed b y dif f ering am ounts of deb ris.

Figure C.5-8 sh ow s tw o op p osite sides of th e strainer. T h e p h oto on th e l ef t sh ow s th e l ef t side of th e strainer l ook ing f rom th e suc tion p ip e ( suc tion p ip e is near th e righ t side of th e p h oto) . T h e p h oto on th e righ t is th e righ t side of th e strainer ( suc tion p ip e is on th e l ef t side of th e p h oto) . T h e c y l inder nearest th e suc tion p ip e on th e l ef t side ap p ears c l eaner th an th e oth er c y l inders b ec ause deb ris h as f al l en of f th e strainer. Figure C.5-9 sh ow s detail s of th ose c y l inder b ottom s. Figure C.5-10 il l ustrates ty p ic al view inside of strainer tub es af ter drain dow n.

C.5.6.2 Test APR1400-HL-0913-2 Af ter th e test, th e suc tion and disc h arge vents w ere op ened very sl ow l y to m inim iz e disturb anc e of th e deb ris b ed, j ust as in th e p revious test. T y p ic al l y draining w ith h eavy deb ris b eds does disturb th e deb ris b ed b ec ause deb ris c an easil y f al l of f vertic al surf ac es, esp ec ial l y w h en th ere is l ittl e h ead l oss ac ross th e deb ris b ed.

In th is test, th e deb ris did not f al l of f th e l ef t c y l inder c l osest to th e suc tion p ip e. B ased on th is c om p arison b etw een Figure C.5-11 and th e l ef t p h oto in Figure C.5-8, th ere is no ef f ec t of agitation on th e deb ris b uil d up to th e strainer. Figure C.5-12 c om p ares th e l ef t side and righ t side of th e strainer af ter drain dow n and it is c l ear th at deb ris f al l s of f of dif f erent c y l inders in an unp redic tab l e m anner. Figure C.5-13 sh ow s th e ends of th e strainer and Figure C.5-14 sh ow s th e ty p ic al view inside of th e strainer tub es af ter drain dow n, note th at deb ris f al l s of f in an unp redic tab l e m anner.

Sim il ar to th e p revious test, no deb ris w as f ound on th e tank f l oor.

C.5.6.3 Test Discrepancies and Nonconformances For test APR1400-HL -0913-2, th e f l ow m eter w as used outside of its c al ib rated range, b ut w el l w ith in its op erating range. T h e m eter w as c al ib rated to 3,407 L / m in ( 900 gp m ) , b ut c an op erate to 9085 L / m in

( 2,400 gp m ) . T h e f l ow m eter h as tw o outp uts an el ec tric al outp ut th at is rec orded on th e data ac q uisition sy stem and a disp l ay on th e m eter itsel f . For th e test, th e el ec tric al outp ut w as resc al ed f rom 3,407 L / m in

( 900 gp m ) to 4,542 L / m in ( 1,200 gp m ) m ax im um . T h e el ec tric al outp ut w as c om p ared to th e disp l ay at several f l ow rates and c om p ared to w ith in 3.8 L / m in ( 1 gp m ) . No f urth er ac tion w as req uired.

For test APR1400-HL -0913-2, f ive ( 5) c h em ic al additions w ere used, instead of f our ( 4) , at th e req uest of 3 3 th e test direc tor. T h e th ird c h em ic al addition w as inc reased f rom 0.189 m ( 50 gal l ons) to 0.379 m ( 100 gal l ons) . T h e additional c h em ic al addition w as used to p rovide additional resol ution in c ase h ead l oss inc reased signif ic antl y .

KEPCO & KHNP C12

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.6 RESULTS OF TESTING T est APR1400-HL -0813-1 w as started on 28 August 2013 and f inish ed on 29 August 2013. T est APR1400-0913-2 w as started on 12 Sep tem b er 2013 and f inish ed on 13 Sep tem b er 2013.

C.6.1 Clean Flow Sw eeps T h e c l ean f l ow sw eep data are sh ow n in T ab l e C.6-1 and p l otted in Figure C.6-1. T h e data f or th e tw o tests are very c onsistent and th e h igh er f l ow p oint f or test APR1400-HL -0913-2 f its th e sam e sec ond order p ol y nom ial c urve as test APR1400-HL -0813-1.

T ab l e C.6-1 Cl ean Fl ow Sw eep Resul ts T est APR1400-HL -0813-1 T est APR1400-HL -0913-2 Fl ow Rate ( gp m ) Head L oss ( in-w ater) Fl ow Rate ( gp m ) Head L oss ( in-w ater) 833 4.3 1003 6.2 739 3.4 738 3.4 660 2.7 665 2.8 582 2.1 573 2.1 493 1.5 495 1.6 658 2.7 662 2.7 833 4.3 1002 6.2 C.6.2 T est Conditions 2 2 T est APR1400-HL -0813-1 w as run assum ing a 55.74 m ( 600 f t ) strainer and test APR1400-HL -0913-2 2 2 w as run assum ing a 46.45 m ( 500 f t ) strainer ( assum ed b l oc k age b y tags and oth er deb ris) ( Ref erenc e

[ 1-1] and [ 1-2] ) . T h e f l ow rate and deb ris am ounts w ere sc al ed b y th e ratio of th e test strainer area to th e p l ant strainer area and th eref ore saw an inc rease f or th e sec ond test of 20% .

T ab l e C.6-2 Com p arison of Head L oss T est Conditions Q uantity APR1400-HL -0813-1 APR1400-HL -0913-2 Fl ow rate ( gp m ) 834 1000 Sil ic on c arb ide( l b m ) 77.4 92.9 Sand m ix ( l b m ) 23.1 27.8 Fib er ( l b m ) ( total ) 1.90 2.30 Ch em ic al ( gal l ons) ( m ax ) 556.5 667.8 T h e as-tested test m atric es are sh ow n in T ab l es C.6-3 and C.6-4. T h e q uantities in th e tab l es indic ate KEPCO & KHNP C13

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 th e am ount of deb ris added during a p artic ul ar sub test. Note th at f or test APR1400-HL -0813-1 onl y th ree c h em ic al additions w ere req uired b ec ause h ead l oss did not inc rease f or th e l ast tw o c h em ic al additions.

For test APR1400-HL -0913-2, th e f ul l c h em ic al l oad w as added in f ive additions.

T ab l e C.6-3 T est M atrix f or APR1400-HL -0813-1

( 1)

Sub test Fl ow rate L atent Fib er ( l b m ) Dirt/ Dust ( l b m ) Coatings ( l b m ) AL OOH ( gal )

P.1 834 0 23.1 77.4 0 F.1 834 0.95 0 0 0 F.2 834 0.95 0 0 0 C.1 834 0 0 0 50 C.2 834 0 0 0 50 C.3 834 0 0 0 50 C.4 834 0 0 0 0 V .1 834 W ater l evel w as reduc ed to 2.0 f t ab ove th e strainer to c h ec k f or vortex ing FS V arious Fl ow w as reduc ed in 100 gp m inc rem ents to 234 gp m Note :

( 1) P : Parric ul ate addition F : Fiver addition C : Ch em ic al addition V : V ortex ing FS : Fl ow sw eet T ab l e C.6-4 T est M atrix f or APR1400-HL -0913-2 Sub test Fl ow rate L atent Fib er ( l b m ) Dirt/ Dust ( l b m ) Coatings ( l b m ) AL OOH ( gal )

P.1 1000 0 27.8 92.9 0 F.1 1000 1.15 0 0 0 F.2 1000 1.15 0 0 0 C.1 1000 0 0 0 50 C.2 1000 0 0 0 50 C.3 1000 0 0 0 100 C.4 1000 0 0 0 200 C.5 1000 0 0 0 267.8 W ater l evel w as reduc ed to 2.0 f eet ab ove th e strainer to c h ec k f or V .1 834 vortex ing FS V arious Fl ow w as reduc ed in 100 gp m inc rem ents to 500 gp m KEPCO & KHNP C14

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.6.3 APR1400-H L-0813-1 Deb ris H ead Loss Results Deb ris h ead l oss test resul ts f or eac h of th e sub tests in T ab l e C.6-3 are sh ow n in T ab l e C.6-5 and p l otted in Figure C.6-2.

T ab l e C.6-5 Head L oss T est Resul ts f or APR1400-HL -0813-1 Sub test Fl ow rate T em p erature Head L oss

( gp m ) ( ° F) ( in-w ater)

P.1 835 82 4.5 F.1 833 82 5.8 F.2 831 83 6.5 C.1 834 84 7.5 C.2 834 85 7.7 C.3 834 85 7.8 FS 729 85 6.0 FS 630 85 4.5 FS 536 85 3.4 FS 430 85 2.2 FS 333 85 1.4 FS 236 86 0.9 C.6.4 APR1400-H L-0913-2 Deb ris H ead Loss Results Deb ris h ead l oss test resul ts f or eac h of th e sub tests in T ab l e C.6-4 are sh ow n in T ab l e C.6-6 and p l otted in Figure C.6-3.

T ab l e C.6-6 Head L oss T est Resul ts f or APR1400-HL -0913-2 Sub test Fl ow rate T em p erature Head L oss

( gp m ) ( ° F) ( in-w ater)

P.1 1009 81 6.4 F.1 999 82 8.1 F.2 998 82 8.4 C.1 996 84 9.0 C.2 998 85 9.4 C.3 999 86 9.6 C.4 1000 88 9.7 C.5 999 88 9.7 FS 899 88 7.9 FS 798 88 6.2 FS 700 88 4.9 FS 601 88 3.6 FS 496 88 2.5 KEPCO & KHNP C15

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.6.5 V ortex T ests For b oth APR1400-HL -0813-1 and APR1400-HL -0913-2, no air entrainm ent or vortex ing w as seen.

Ph otograp h s and video w ere tak en of th e strainer sub m erged at tw o f eet of w ater at test f l ow rate. For test APR1400-HL -0813-1 af ter th e f l ow sw eep w as c om p l ete, th e f l ow rate w as inc reased to th e target f l ow rate to dem onstrate th e l ac k of vortex f orm ation f or test w itnesses. No vortic es are identif ied during th e tests ( Figure C.6-4) .

C.7 QUALITY ASSURANCE Al l q ual ity -rel ated ac tivities w ere p erf orm ed in ac c ordanc e w ith th e Continuum Dy nam ic s, Inc . Q ual ity Assuranc e M anual ( Ref erenc e [ 7-1] ) . Q ual ity -rel ated ac tivities are th ose w h ic h are direc tl y rel ated to th e p l anning, ex ec ution and ob j ec tives of th e test. Sup p orting ac tivities suc h as test ap p aratus design, f ab ric ation and assem b l y are not c ontrol l ed b y th e C.D.I. Q ual ity Assuranc e M anual . C.D.I.' s Q ual ity Assuranc e Program p rovides f or c om p l ianc e w ith th e rep orting req uirem ents of 10 CFR Part 21. Al l instrum ent c ertif ic ations, instrum ent c al ib rations, testing p roc edures, data reduc tion p roc edures, and test resul ts are c ontained in a Design Rec ord Fil e w h ic h ( up on c om p l etion) w il l b e k ep t on f il e at C.D.I. of f ic es.

KEPCO & KHNP C16

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.8 CONCLUSION T o devel op ex p erim ental h ead l oss data assoc iated w ith th e sp ec if ied deb ris l oadings, tw o tests

( APR1400-HL -0813-1 and APR1400-HL -0913-2) w ere p erf orm ed. T h e f irst test w as p erf orm ed using an 2 2 ef f ec tive surf ac e area of 55.74 m ( 600 f t ) and th e sec ond test w as p erf orm ed using an ef f ec tive surf ac e 2 2 area of 46.45 m ( 500 f t ) . T h e dif f erenc e b etw een th e f irst and sec ond h ead l oss test is th e c h ange in 2 2 ef f ec tive surf ac e area of th e strainer to c onsider a 9.29 m ( 100 f t ) p enal ty of sac rif ic ial strainer surf ac e.

T h is w as ac c om p l ish ed b y inc reasing th e test f l ow rate f or th e sec ond test f rom 3,157 L / m in ( 834 gp m ) to 3,785 L / m in ( 1,000) gp m and inc reasing th e m ass of deb ris p er sq uare f oot.

2 2 T h e m ax im um h ead l oss f or th e 46.45 m ( 500 f t ) ef f ec tive strainer area w ith th e m ax im um deb ris l oad is 24.69 c m -w ater ( 0.81 f t-w ater) at th e design f l ow rate and inc l udes a c l ean sc reen c om p onent of 15.85 c m -

w ater ( 0.52 f t-w ater) . T h eref ore, th e deb ris onl y h ead l oss f or b oth tests is essential l y th e sam e at 8.84 c m -w ater ( 0.29 f t-w ater) . W h il e th e f l ow rates/ deb ris m ass p er unit area is sl igh tl y dif f erent, th e resul ts are nearl y identic al and rep eatab l e and c onsiderab l y l ess th an th e 60.96 c m -w ater ( 2 f t-w ater) al l ow ab l e h ead l oss. T h is is due to th e very l ow deb ris l oad th at is insuf f ic ient to c over th e sc reen c om p l etel y , sim il ar to th at of th e c l ean p l ant c riteria.

T ab l e C.8-1 Final Head L oss T est Resul ts Strainer w ith Strainer w ith 2 2 2 2 46.45 m ( 500 f t ) 55.74 m ( 600 f t )

Cl ean strainer 15.85 c m -w ater 10.97 c m -w ater h ead l oss ( 0.52 f t-w ater) ( 0.36 f t-w ater) 8.84 c m -w ater 8.84 c m -w ater Deb ris h ead l oss

( 0.29 f t-w ater) ( 0.29 f t-w ater)

T otal strainer 24.69 c m -w ater 19.81 c m -w ater h ead l oss ( 0.81 f t-w ater) ( 0.65 f t-w ater)

T h ese test resul ts w ere ex p erim ental l y m easured in a test f l uid at ap p rox im atel y 31.1 ° C ( 88 ° F) .

T h eref ore, it is c onservative to use th ese val ues at h igh er tem p eratures sinc e f l uid density and visc osity w il l dec rease w ith inc reasing tem p erature.

For strainer vortex ing, visual ob servations w ere p erf orm ed and no vortic es w ere ob served.

KEPCO & KHNP C17

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 C.9 REFERENCES 1-1 APR1400-E-A-T ( NR) -13002-NP, " APR1400 IRW ST ECCS Sum p Strainer Prototy p e Hy draul ic Q ual if ic ation T est Pl an," Rev. 1, KHNP, August 2013.

1-2 T est Pl an No. 1300462.402, " APR1400 IRW ST ECCS Sum p Strainer Prototy p e Hy draul ic Q ual if ic ation T est Pl an," Struc tural Integrity Assoc iates, Rev. 2, Sep tem b er 2013.

4-1 Saf ety Eval uation b y th e Of f ic e of Nuc l ear Reac tor Regul ation Rel ated to NRC Generic L etter 2004-02, Nuc l ear Energy Institute Guidanc e Rep ort ( Prop osed Doc um ent Num b er NEI 04-07) ,

" Pressuriz ed W ater Reac tor Sum p Perf orm anc e Eval uation M eth odol ogy ," Nuc l ear Energy Institute, Dec em b er 2004.

4-2 NU REG/ CR-6808, " Know l edge B ase f or th e Ef f ec ts of Deb ris on Pressuriz ed W ater Reac tor Em ergenc y Core Cool ing Sum p Perf orm anc e," U .S. Nuc l ear Regul atory Com m ission, Feb ruary 2003.

4-3 W CAP-16530-NP-A, " Eval uation of p ost-Ac c ident Ch em ic al Ef f ec t in Containm ent Sum p Fl uid to Sup p ort GSI-191," Rev.0, W estingh ouse El ec tric Corp oration, Ap ril 2008.

4-4 " Final Saf ety Eval uation b y th e Of f ic e of Nuc l ear Reac tor Regul ation, T op ic al Rep ort W CAP-16530-NP-A Eval uation of Post-Ac c ident Ch em ic al Ef f ec ts in Containm ent Sum p Fl uids to Sup p ort GSI-191 ," U .S. Nuc l ear Regul atory Com m ission, Dec em b er 2007.

5-1 " Z OI Fib rous Deb ris Prep aration: Proc essing, Storage, and Handl ing," Nuc l ear Energy Institute, Revision 1 J anuary 2012.

7-1 " Q ual ity Assuranc e M anual ," Continuum Dy nam ic s, Inc ., Revision 14, Feb ruary 2006.

KEPCO & KHNP C18

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.2-1 Prototype Strainer in the T est T ank KEPCO & KHNP C19

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.2-2 Pump (on lef t), and Data Acq uisition Flow M eter/ DP Cells (on right)

KEPCO & KHNP C20

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.2-3 Flow Schematic of T est Setup KEPCO & KHNP C21

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.3-1 T est Strainer Draw ing KEPCO & KHNP C22

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.4-1 Aged Fib er Sample KEPCO & KHNP C23

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.4-2 Fib er U sed in APR1400-H L-0813-1 KEPCO & KHNP C24

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.4-3 Fib er U sed in APR1400-H L-0913-2 KEPCO & KHNP C25

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.4-4 M easured Siz e Distrib ution of Black Silicon Carb ide KEPCO & KHNP C26

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.5-1 T ypical Particulate Addition (Silicon Carb ide on Lef t, Sand M ix ture on Right)

KEPCO & KHNP C27

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.5-2 T ypical Fib er Fines Addition f or APR1400-H L-0813-1 KEPCO & KHNP C28

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.5-3 T ypical Fib er Fines Addition f or APR1400-H L-0913-2 KEPCO & KHNP C29

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.5-4 T ypical Chemical Deb ris Addition KEPCO & KHNP C30

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.5-5 T est Facility Layout KEPCO & KHNP C31

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-6 Post-test During Draining (Suction Pipe is at T op of Photo)

KEPCO & KHNP C32

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-7 Post-test During Draining (Suction Pipe is at Right)

KEPCO & KHNP C33

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-8 Post-test During Draining (Lef t and Right Sides of the Strainer)

KEPCO & KHNP C34

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-9 Cylinders Bottom Lef t Side of Strainer Show ing Deb ris H aving Fallen Of f Strainer (Aw ay From (on top) and Near (on b ottom) Suction Pipe)

KEPCO & KHNP C35

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-10 T ypical V iew Inside Strainer T ub es Af ter Drain Dow n KEPCO & KHNP C36

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-11 Lef t Side of Strainer During Drain Dow n (Suction Pipe is on Right of Photo)

KEPCO & KHNP C37

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-12 Comparison of Lef t and Right Side of the Strainer Af ter Drain Dow n KEPCO & KHNP C38

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-13 Comparison of Ends of the Strainer Af ter Drain Dow n KEPCO & KHNP C39

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure C.5-14 T ypical V iew Inside of Strainer T ub es Af ter Drain Dow n KEPCO & KHNP C40

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.6-1 Clean Flow Sw eep Data KEPCO & KHNP C41

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.6-2 T ime H istories of H ead Loss, Flow Rate, and T emperature (APR1400-H L-0813-1)

KEPCO & KHNP C42

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.6-3 T ime H istories of H ead Loss, Flow Rate, and T emperature (APR1400-H L-0913-2)

KEPCO & KHNP C43

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure C.6-4 V ortex Identif ication During APR1400-H L-0813-1 (on lef t) and APR1400-H L-0913-2 (on right)

KEPCO & KHNP C44

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix D Bypass Test Report for the IRWST Sump Strainer KEPCO & KHNP D1

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TABLE OF CONTENTS D.1 INTRODUCTION .................................................................................................... D5 D.2 TEST FACILITY DESCRIPTION ............................................................................. D6 D.2.1 Fl ow L oop ....................................................................................................................................... D6 D.2.2 Instrum entation ............................................................................................................................... D6 D.3 TEST PROTOTYPE ................................................................................................ D7 D.4 DEBRIS DESCRIPTION ......................................................................................... D8 D.5 TEST PROCEDURE

SUMMARY

............................................................................. D9 D.5.1 Deb ris Prep aration .......................................................................................................................... D9 D.5.2 T est Setup ....................................................................................................................................... D9 D.5.3 Fil ter W eigh ing ................................................................................................................................ D9 D.5.4 T est Initiation ................................................................................................................................. D10 D.5.5 Fil ter Sw ap p ing ............................................................................................................................. D10 D.5.6 Deb ris Addition .............................................................................................................................. D10 D.5.7 T est T erm ination ............................................................................................................................ D10 D.5.8 Post T est Ob servations ................................................................................................................. D11 D.5.9 T est Disc rep anc ies and Nonc onf orm anc es .................................................................................. D11 D.6 RESULTS OF TESTING ....................................................................................... D12 D.6.1 Fib er Cap tured .............................................................................................................................. D12 D.6.2 T im e Histories of Head L oss, Fl ow Rate, and T em p erature.......................................................... D13 D.6.3 B y p ass Fib er L ength ..................................................................................................................... D13 D.7 QUALITY ASSURANCE ....................................................................................... D14 D.8 CONCLUSION ..................................................................................................... D15 D.9 REFERENCES ..................................................................................................... D17 KEPCO & KHNP D

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF TABLES T ab l e D.6-1 Seq uenc e of Events f or T est APR1400-B y p ass-0913-1 .................................................. D12 T ab l e D.6-2 Sum m ary of f ib er b y p ass ................................................................................................. D13 T ab l e D.6-3 B y p assed Fib er L ength Distrib ution in V al ue ................................................................... D13 T ab l e D.8-1 Cum ul ative Prototy p e B y p ass Deb ris .............................................................................. D15 T ab l e D.8-2 APR1400 B y p ass Deb ris Q uantities ................................................................................ D16 KEPCO & KHNP D

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 LIST OF FIGURES Figure D.2-1 Prototy p e Strainer in th e T est T ank .................................................................................. D18 Figure D.2-2 Fil ter Housings ................................................................................................................. D19 Figure D.2-3 Pum p ( on l ef t) , and Data Ac q uisition Fl ow M eter/ DP Cel l s ( on righ t) .............................. D20 Figure D.2-4 Fl ow Sc h em atic of T est Setup ......................................................................................... D21 Figure D.3-1 T est Strainer Draw ing ...................................................................................................... D22 Figure D.4-1 Aged Fib er Sam p l e .......................................................................................................... D23 Figure D.4-2 Sim ul ated L atent Deb ris Susp ended in W ater ................................................................. D24 Figure D.5-1 T y p ic al Fib er Fine Addition ............................................................................................... D25 Figure D.5-2 T est Fac il ity L ay out .......................................................................................................... D26 Figure D.5-3 Strainer Af ter T est and Drain Dow n ................................................................................. D27 Figure D.5-4 Strainer T ub e Inside Af ter T est and Drain Dow n .............................................................. D28 Figure D.5-5 Detail of th e Fib er B uil dup Outside of th e Fib er T ub e...................................................... D29 Figure D.6-1 T im e Histories of Head L oss, Fl ow Rate, and T em p erature ............................................ D30 Figure D.6-2 B y p assed Fib er L ength Distrib ution ................................................................................. D31 KEPCO & KHNP D

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.1 INTRODUCTION If a l oss of c ool ant ac c ident ( L OCA) w ere to oc c ur, it is p ostul ated th at th is L OCA c oul d generate and transp ort deb ris to th e Em ergenc y Core Cool ing Suc tion ( ECCS) strainer. Som e of th e deb ris dep osited on th e ECCS strainer m ay p ass th rough th e strainer and c oul d c h al l enge th e l ong term c ore c ool ing c ap ab il ity of th e p l ant. T h e p rim ary deb ris ty p e of c onc ern is f ib rous m aterial w h ic h p otential l y c oul d f orm a deb ris b ed dow nstream of th e strainer, f or ex am p l e on th e f uel grids. Partic ul ate and c h em ic al deb ris are assum ed to p ass th rough th e strainer, and are th eref ore ex c l uded f rom th e b y p ass test.

T h e p urp ose of th is test is to m easure th e q uantity of f ib er th at c an p ass th rough th e ECCS strainer. T h e test w as c onduc ted f ol l ow ing a test p l an ( Ref erenc e [ 1-1] ) devel op ed b y Struc tural Integrity Assoc iates.

KEPCO & KHNP D5

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.2 TEST FACILITY DESCRIPTION D.2.1 Flow Loop T h e test f ac il ity c onsists of an ap p rox im atel y 4.57 m ( 15 f t) diam eter tank th at is 2.13 m ( 7 f t) deep . T h e f l ow returns into th e tank f rom a 6 inc h p ip e w ith a tee th at is p ointed at th e f l oor in th e c enter of th e tank .

T h e ex it of th e tee is ap p rox im atel y 0.05 m ( 2 inc h ) ab ove th e f l oor so th at th e return f l ow sw eep s al ong 3

th e f l oor th en up th e tank w al l s to h el p susp end deb ris. T h e tank c an h ol d ap p rox im atel y 35.96 m ( 9500 gal l ons) of w ater. T h e tank w as c overed b y a tarp to p revent dust and deb ris f rom f al l ing into th e tank .

T h e test strainer is l oc ated nex t to th e return p ip e w ith th e strainer p l enum m ounted 0.15 m ( 6 inc h ) ab ove th e tank f l oor. T h e top of th e strainer el em ents are 1.19 m ( 46.75 inc h ) ab ove th e tank f l oor. Six agitators ( trol l ing m otors) are l oc ated at ap p rox im atel y every 60 degrees at an ap p rox im atel y 3.66 m ( 12 f t) diam eter ( see Figures D.2-1 and D.2-2) .

T h e suc tion p ip e is attac h ed to th e strainer and runs to th e Godw in CD150M p um p . T h e disc h arge of th e p um p goes to a f l ow m eter, f l ow c ontrol val ve, and th en b ac k into th e tank ( see Figures D.2-2 and D.2-3, and Figure D.2-4 f or a sc h em atic ) .

Fl ow rate c an b e c ontrol l ed b y a c om b ination of a variab l e f req uenc y drive ( V FD) th at drives th e p um p , th e gate val ve, or a b y p ass l ine w h ic h p rovides a sh ort c irc uit p ath b etw een th e suc tion and disc h arge of th e p um p . T y p ic al l y , th e V FD is used to c ontrol th e f l ow rate during a test, unl ess very l ow f l ow rates need to b e ac h ieved.

D.2.2 Instrumentation Head l oss ac ross th e strainer w as m easured b y tw o indep endent Rosem ount m odel 1151 dif f erential p ressure transduc ers. One transduc er w as sc al ed to 0-100 in of w ater and th e sec ond w as sc al ed to 0 -

7.62 m ( 0 - 300 inc h ) of w ater. T h ese transduc ers w ere c al ib rated to + / -0.125% of th eir range. T h e l ow side of th e dif f erential p ressure transduc er w as c onnec ted to th e p ressure tap on th e strainer p l enum and th e h igh side of th e p ressure transduc ers w as c onnec ted to a tap on th e tank w al l .

Fl ow rate w as m easured b y a six -inc h Om ega m odel M G1000 el ec trom agnetic f l ow m eter. T h e f l ow m eter w as instal l ed on th e disc h arge side of th e p um p m ore th an 50 diam eters up stream of th e p um p w ith a straigh t sec tion of p ip e up stream and dow nstream of th e f l ow m eter. A f l ow c ontrol val ve w as instal l ed dow nstream of th e straigh t sec tion of p ip ing.

W ater tem p erature w as m easured w ith a ty p e T th erm oc oup l e instal l ed in th e tank near th e w ater surf ac e.

T h e th erm oc oup l e w as c onnec ted to an Om ega DP-41 T C-A p roc ess m eter.

Al l of th ese instrum ents w ere c onnec ted to a Dataq DI-220 data ac q uisition sy stem running L SP60 sof tw are. T h is sof tw are rec ords data every tw o sec onds to disk in tab del im ited f orm at in engineering units. T h e sof tw are al so p rovides p l otting and digital disp l ay s of al l of th e instrum entation b eing rec orded.

KEPCO & KHNP D6

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.3 TEST PROTOTYPE A p rototy p e T ransc o strainer w as tested ( see Figures D.2-1 and D.3-1) . T h e strainer c onsists of th ree strainer c artridges eac h w ith f our tub es b ol ted to a p l enum th at al l ow s a f l ow p ath f rom eac h tub e to th e p um p suc tion p ip e. T h e th ree c artridges w ere l ab el l ed as C4570-004, C4570-005, and C4570-006. T h e 2 2 surf ac e area of th is c onf iguration is 6.97 m ( 75.1 f t ) w ith p erf orated p l ate h ol e siz e of 2.38 m m ( 0.094 inc h ) in Ref erenc e [ 1-1] . T h e p l enum w as m ounted 0.15 m ( 6 inc h ) ab ove th e tank f l oor.

KEPCO & KHNP D7

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.4 DEBRIS DESCRIPTION For th is test f ib er, f ines w ere tested to sim ul ate l atent deb ris. Fib er w as p rep ared f rom aged Nuk on f ib ergl ass. T h e f ib ergl ass w as ob tained h eat treated f rom Perf orm anc e Contrac ting Inc . l ot num b er J -

006-12HT

• L N-1840. T h e h eat treating p roc ess f ol l ow ed PCI p roc edure DPP-01 w h ic h h eated one side of th e insul ation on a h ot p l ate at 300 ° C ( 572 ° F) f or 6 to 8 h ours. T h e rec eived insul ation w as insp ec ted visual l y to c onf irm th at th e h eat treatm ent p roduc ed a c ol or gradient ap p rop riate f or aged f ib er ( see Figure D.4-1) .

T h e use of f ib ergl ass insul ation, suc h as Nuk on is rec om m ended as a surrogate f or dry l atent deb ris

( Ref erenc e [ 4-1] ) . T h e f ib er w as p roc essed into f ines, m ostl y c l ass 1 and 2, as def ined in Ref erenc e [ 4-2] )

f or use in th e test. T h e p roc essing step s are desc rib ed in Sec tion 5 and p h otograp h s of th e end resul t of th e susp ended f ib ers are sh ow n in Figure D.4-2.

KEPCO & KHNP D8

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.5 TEST PROCEDURE

SUMMARY

D.5.1 Deb ris Preparation Fib er f ines w ere p rep ared b ased on NEI guidanc e ( Ref erenc e [ 5-1] ) . Aged Nuk on f ib ergl ass insul ation w as c ut into ap p rox im atel y 7.62 c m b y 7.62 c m ( 3 inc h b y 3 inc h ) p iec es. T h e c ut p iec es w ere th en sh redded in a l eaf sh redder/ c h ip p er, and th e sh redded f ib er w as th en p assed th rough th e l eaf sh redder and additional tw o tim es. T h e f ib er w as sh redded th ree tim es. T h e sh red f ib er w as th en w eigh ed into 4 b atc h es of 0.18 k g ( 0.4 l b m ) . A b atc h w as p l ac ed into p l astic c ontainer ( ap p rox im atel y 0.121 m 3 ( 32 gal l ons) ) w ith ap p rox im atel y 0.008 m 3 ( 2 gal l ons) of w ater. T h e f ib er w as th orough l y w et. T h e f ib er w as th en sep arated using a p ressure w ash er w ith a f an noz z l e f or 4 m inutes.

3 T h e w ater f ib er m ix ture w as th en f urth er dil uted into eigh t 0.019 m ( 5 gal l on) b uc k ets w ith a total of 0.011 3

m ( 3 gal l ons) of w ater in eac h b uc k et. Im m ediatel y p rior to adding th e f ib er, th e f ib er w as agitated w ith a p rop el l er m ix er on h igh f or one m inute. A sam p l e of th is f ib er w ater m ix ture w as tak en to ensure th e p roc ess p roduc ed f ines th at w ere nearl y al l c l ass 1 and 2 f ines ( Ref erenc e [ 4-2] ) ( see Figure D.4-2) . T h e f ib er m ix ture w as added to th e tank and th ere w ere no f ib er c l um p s as th e f ib er w as p oured into th e tank .

Ph otograp h s and video w ere tak en of th e f ib er addition ( f or ex am p l e see Figure D.5-1) .

D.5.2 T est Setup T h e test setup c onsisted of c l eaning th e f ac il ity and c l eaning and assem b l ing th e strainer as sh ow n in Figure D.2-1. T h e c onf iguration is sk etc h ed in Figure D.5-2. T h e strainer w as c h ec k ed to ensure th ere w ere no gap s greater th an 2.38 m m ( 0.094 inc h ) . T h e tank and p ip ing w ere f il l ed w ith w ater at 22.2 ° C

( 72 ° F) , w h ic h is ab ove th e 15.6 ° C ( 60 ° F) m inim um req uired in th e test p l an. T h e w ater l evel w as set 24 inc h es ab ove th e top of th e strainer tub es.

-5 Al l 9 f il ter h ousings w ere f itted w ith 1 m ( 3.94x 10 inc h ) f el t f il ters to c l ean th e w ater p rior to th e test starting. T h e data ac q uisition sy stem w as started and th en th e p um p w as turned on. T h e f l ow rate w as set to 3,407 L / m in ( 900 gp m ) , sl igh tl y greater th an th e target f l ow rate of 3,157 L / m in ( 834 gp m ) , to im p rove p re-f il tering. T h e w ater w as f il tered f or greater th an 10 p ool turn over tim es ( PT Os) .

D.5.3 Filter Weighing Eac h f il ter w as num b ered to identif y th e f il ter. Fil ters w ere stored in a room at 35% rel ative h um idity and 25.6 ° C ( 78 ° F) f or several day s p rior to th e test. T h e f il ters w ere w eigh ed individual l y and in group s of eigh t, sinc e th ey w oul d b e used in group s of eigh t. T h e f il ters w ere w eigh ed in th e sam e room in w h ic h th ey w ere stored.

Af ter th e test th e f il ters w ere al l ow ed to dry in l ab c onditions. Af ter m ost of th e w ater w as rem oved f rom th e f il ters, th e f il ters w ere h ung in rac k s in th e f il ter w eigh ing room at th e sam e c onditions th ey w ere initial l y stored and w eigh ed.

T h e f il ters w ere al l ow ed to dry f or several day s and th en w eigh ed th ree tim es over a p eriod of several h ours to ensure th e w eigh t w as stab l e. T h e p ost-test f il ters w ere w eigh ed in th e sam e group s of eigh t th at th ey w ere used ( and original l y w eigh ed) .

KEPCO & KHNP D9

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.5.4 T est Initiation T h e test w as initiated b y setting th e f l ow rate to 3,157 L / m in ( 834 gp m ) and sw ap p ing out th e p re-f il ters f or p re- w eigh ed c ontrol f il ters. Data w as al ready b eing ac q uired f or h ead l oss ac ross th e strainer, f l ow rate, and w ater tem p erature. Control f il ters w ere p l ac ed in eigh t of th e f il ter h ousings w ith f l ow going th rough eac h of th ese eigh t f il ters. T h e ninth f il ter h ousing rem ained sh ut of f and a p re-w eigh ed, num b ered f il ter th at w oul d b e used to c ol l ec t f ib er w as p l ac ed in th at h ousing. No f l ow w as going th rough th at f il ter during th e c ontrol f il ter p ortion of th e test.

D.5.5 Filter Sw apping Fil ter sw ap p ing w as p erf orm ed to m inim iz e f l ow disturb anc e and to avoid disturb ing th e deb ris b ed on th e strainer. Fil ters w ere sw ap p ed one at a tim e ( onl y a p ortion of th e f l ow c oul d b e disturb ed) . T h ere w ere al w ay s eigh t f il ters ac tive and one f il ter w ith no f l ow . T o sw ap f il ters th e val ve on th e dow nstream side of th e unused f il ter w as op ened. T h en th e up stream val ve of th e unused f il ter w as op ened w h il e th e up stream val ve of th e neigh b oring ac tive f il ter w as c l osed. T h e new f il ter w as now ac tive.

T h e dow nstream val ve on th e used f il ter w as c l osed c om p l etel y isol ating th e f il ter. T h e vent val ve on th e f il ter w as op ened and th en th e drain val ve w as op ened. T h e f il ter top w as op ened and w h en th e w ater l evel in th e f il ter h ousing w as b el ow th e top of th e f il ter, th e drain val ve w as c l osed, th e f il ter b ag w as rem oved and its num b er w as rec orded. Note th at w ater draining f rom th e f il ter h ousing drained th rough th e f il ter b ag and any f ib er w oul d b e c ap tured b y th e f il ter.

A new p re-w eigh ed num b ered f il ter ( b el onging to th e sam e set of f il ters) w as p l ac ed in th e op en f il ter h ousing. T h e f il ter num b er w as rec orded. T h e f il ter w as seal ed into th e f il ter h ousing. Air w as rem oved f rom th e f il ter h ousing b y c rac k ing th e up stream val ve and al l ow ing air to ex it f rom th e vent val ve.

Any w ater th at ex ited th rough th e vent p assed th rough th e rem oved f il ter to c ap ture any f ib er in th e w ater.

T h e f il ter w as th en h ung up on a rac k to dry .

T h is p roc ess w as rep eated f or al l f il ters and th e l ast f il ter rem ained c l osed until th e nex t f il ter c h ange.

D.5.6 Deb ris Addition Af ter f il ter sw itc h ing w as c om p l ete f ib er w as added to th e tank . Fib er f ines w ere added f rom eigh t b uc k ets and p oured into th e tank around th e p erim eter w h ere th e up w el l ing c aused h igh l evel of turb ul enc e. T h e f ib ers w ere susp ended in th e w ater and added to th e tank w ith out any visib l e f ib er c l um p s.

T h ere w ere f our f ib er additions of 0.18 k g ( 0.4 l b m ) of f ines.

D.5.7 T est T ermination T h e p re-f il tering c ontinued f or a m inim um of 10 PT Os p rior to term inating th is seq uenc e and sw ap p ing f il ters f or c ontrol f il ters. Fil ter sw ap p ing oc c urred af ter a m inim um of 3 PT Os f or th e c ontrol f il ters. A m inim um of 7 PT Os w as used p rior to term inating a f ib er addition b y sw ap p ing f il ters. Af ter eac h f ib er addition th e p ool w as c h ec k ed visual l y th at al l of th e f ib er w as on th e strainer. If no f ib er w as seen in th e KEPCO & KHNP D10

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 p ool , th en af ter 2 additional PT Os f ib er sw ap p ing w as started.

Af ter th e f ourth b atc h of f ib er w as added and 7 PT Os w ere c om p l eted th e test w as term inated b y stop p ing th e p um p . T h e tank w as th en drained w h il e p h otograp h ing and videotap ing th e deb ris on th e strainer and th e c l ean tank . T h e l ast set of f il ters w ere rem oved f rom th e f il ter h ousings and al l ow ed to dry .

D.5.8 Post T est Ob servations T h e f ib er deb ris w as c ol l ec ted on th e b ottom of th e strainer tub es on b oth th e inside and outside. T h e f ib er w as b uil t up to a h eigh t of 12.70 c m - 20.32 c m ( 5 - 8 inc h ) ( see Figures D.5-3 and D.5-4) . T h e deb ris b ed w as l ess th an 2.54 c m ( 1 inc h ) th ic k at th e b ottom and tap ered to a th in c oating at th e top of th e f ib er ( see Figure D.5-5) . T h e deb ris rem ained on th e strainer af ter th e drain dow n and no f ib er w as f ound in th e tank .

D.5.9 T est Discrepancies and Nonconf ormances None.

KEPCO & KHNP D11

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.6 RESULTS OF TESTING A singl e b y p ass test w as run. T h e b y p ass test w as identif ied as APR1400-B y p ass-0913-1. Four b atc h es of f ines rep resenting l atent deb ris w ere added at th e tim es sh ow n in T ab l e D.6-1 and grap h ic al l y in Figure D.6-1. Note th at tim e z ero on th e p l ot rep resents 9: 36 AM w h en th e data ac q uisition unit w as started. A PT O during p re-f il tering w as 9 m inutes and during th e test w as 10 m inutes. Note th at during f il ter sw itc h ing and venting al l w ater th at m igh t c ontain w ater stil l p assed th rough th e f il ters.

T ab l e D.6-1 Seq uenc e of Events f or T est APR1400-B y p ass-0913-1 Event T im e Num b er of PT Os Pre-f il tering 9: 46AM to 12: 31 PM 18 Sw itc h f il ters 12: 31 PM to 1: 05PM 3.4 Control f il ter 1: 10PM to 1: 40PM 3 Sw itc h f il ters 1: 41PM to 2: 05PM 2.4 First f ib er addition 2: 39PM to 2: 45PM 0.6 Col l ec t f irst f ib er addition 2: 45PM to 4: 00PM 7.5 Sw itc h Fil ters 4: 13PM to 4: 43 PM 3 Sec ond f ib er addition 5: 00PM to 5: 05PM 0.5 Col l ec t sec ond f ib er addition 5: 05PM to 6: 18PM 7.3 Sw itc h Fil ters 6: 18PM to 6: 45 PM 2.7 T h ird f ib er addition 6: 59PM to 7: 04PM 0.5 Col l ec t th ird f ib er addition 7: 04PM to 8: 15PM 7.1 Sw itc h Fil ters 8: 16PM to 8: 43 PM 2.7 Fourth f ib er addition 8: 51PM to 8: 56PM 0.5 Col l ec t f ourth f ib er addition 8: 56PM to 10: 10PM 7.4 D.6.1 Fib er Captured T ab l e D.6-2 l ists th e am ount of f ib er f ines added and th e c h ange in w eigh t f or th e c ontrol f il ters and th e f il ters th at c ap tured f ib er af ter eac h f ib er addition. Note th at m ost of th e strainer area rem ained op en f or al l additions ( see Figure D.5-3) . Eac h f ib er addition w as term inated af ter th e tank ap p eared visual l y c l ear of f ib er, w h ic h w as c onf irm ed near 5 PT O, th en w aiting tw o additional PT O f or a m inim um tim e of 7 PT O

( see T ab l e D.6-1) . PT O w as c ounted f rom th e end of eac h f ib er addition.

KEPCO & KHNP D12

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e D.6-2 Sum m ary of f ib er b y p ass Fil ter w eigh t c h ange Condition Fib er added ( g / l b m )

( g/ lb m )

Control f il ters 0/ 0 0/ 0 Af ter f irst f ib er addition 181.2 g / 0.40 l b m 37.16 / 0.08 Af ter sec ond f ib er addition 181.2 g / 0.40 l b m 29.66 / 0.07 Af ter th ird f ib er addition 181.2 g / 0.40 l b m 28.04 / 0.06 Af ter f ourth f ib er addition 181.2 g / 0.40 l b m 29.08 / 0.06 D.6.2 T ime H istories of H ead Loss, Flow Rate, and T emperature A p l ot of th e h ead l oss, f l ow rate and tem p erature are sh ow n as a f unc tion of tim e in Figure D.6-1.

D.6.3 Bypass Fib er Length Fib er th at b y p assed th e strainer w as c ap tured in f il ter b ags dow nstream of th e test strainer. A random am p l e of f ib er w as rem oved f rom tw o of th e f il ter b ags, num b er 29 and num b er 21, f rom test APR1400-B y p ass-0913-1. T h ese f ib er sam p l es w ere f rom th e sec ond and th ird addition of th e f our f ib er additions.

T h e sam p l es w ere ob tained b y m anual l y rem oving a f ib er f rom th e f il ter b ags. T h ese f ib er sam p l es w ere anal y z ed w ith L orentz en and W ettre Fib er T ester to determ ine f ib er l ength distrib ution f or b y p assed f ib er.

A total of 164,328 f ib ers ( 104,228 f ib ers f or b ag num b er 29, and 60,100 f ib ers f or b ag num b er 21) w ere identif ied w ith 59.4% l ess th an or eq ual to 0.5 m m ( 0.020 inc h ) in l ength , 26.3% b etw een 0.5 m m ( 0.020 inc h ) and 1.0 m m ( 0.039 inc h ) in l ength , and 14.3% th at w ere greater th an 1.0 m m ( 0.039 inc h ) in l ength

( T ab l e D.6-3) . T h e b y p assed f ib er l ength distrib ution is sh ow n in Figure D.6-2.

T h ese f ib er l ength s are l onger th an th e siz e distrib ution of b y p assed f ib er general l y used b y th e p ressuriz ed w ater reac tor ow ners group , w h ic h h as 77% of th e f ib ers l ess th an 0.5 m m ( 0.020 inc h ) , 18%

b etw een 0.5 m m ( 0.020 inc h ) and 1.0 m m ( 0.039 inc h ) , and 5% greater th an 1.0 m m 1 m m ( 0.039 inc h )

( Ref erenc e [ 6-1] ) , b ut th is m ak es th e f ib er l ength distrib ution c onservative f or dow nstream ef f ec ts

( Ref erenc e [ 6-1] ) .

T ab l e D.6-3 B y p assed Fib er L ength Distrib ution in V al ue Perc entage ( % ) T otal Ref .

L ength

(% ) (% )

Fil ter # 29 Fil ter # 21 Fib er l ength 0.5 m m 60.0 58.4 59.4 77 0.5 m m < Fib er l ength 1.0 m m 26.0 26.7 26.3 18 1.0 m m < Fib er l ength 14.0 14.9 14.3 5 KEPCO & KHNP D13

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.7 QUALITY ASSURANCE Al l q ual ity -rel ated ac tivities w ere p erf orm ed in ac c ordanc e w ith th e Continuum Dy nam ic s, Inc . Q ual ity Assuranc e M anual ( Ref erenc e [ 7-1] ) . Q ual ity -rel ated ac tivities are th ose w h ic h are direc tl y rel ated to th e p l anning, ex ec ution and ob j ec tives of th e test. Sup p orting ac tivities suc h as test ap p aratus design, f ab ric ation and assem b l y are not c ontrol l ed b y th e C.D.I. Q ual ity Assuranc e M anual . C.D.I.' s Q ual ity Assuranc e Program p rovides f or c om p l ianc e w ith th e rep orting req uirem ents of 10 CFR Part 21. Al l instrum ent c ertif ic ations, instrum ent c al ib rations, testing p roc edures, data reduc tion p roc edures, and test resul ts are c ontained in a Design Rec ord Fil e w h ic h ( up on c om p l etion) w il l b e k ep t on f il e at C.D.I. of f ic es.

KEPCO & KHNP D14

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.8 CONCLUSION T o estab l ish th e q uantity of f ib rous deb ris th at c oul d p otential l y p enetrate th e strainer, p rototy p e test w as p erf orm ed. T h e test w as p erf orm ed w ith onl y f ib rous deb ris as adding p artic ul ates m ay reduc e th e am ount of b y p ass deb ris due to c l ogging at th e strainer. Additional l y , th e m ost c onservative ap p roac h w ith b y p ass test is to assum e al l sum p strainers are ac tive running at th e m ax im um f l ow rates sinc e it stands to reason th at m ore m ass f l ow rate and m ore p erf orated p l ates c auses m ore b y p ass.

T o determ ine th e p l ant strainer b y p ass deb ris, th e c um ul ative q uantity of b y p ass deb ris f rom th e p rototy p e test w as sc al ed b y a ratio of th e p l ant strainer to th e p rototy p e strainer ( 600/ 75.1 = 8.0) . T h e c um ul ative b y p ass q uantities f or deb ris l oads are p resented in T ab l e D.8-1. T h e total b y p ass deb ris is th e sum of th e b y p ass deb ris f or al l ac tive strainers as p resented in T ab l e D.8-2.

T otal b y p ass deb ris f or th e APR1400 w ith 6.80 k g ( 15 l b m ) of l atent f ib er is 1.67 k g ( 3.68 l b m ) ( ~ 25% ) .

T h e f ib rous deb ris siz e distrib ution is m easured to b e 59.4% sh orter th an 0.5 m m ( 0.020 inc h ) , 26.3%

b etw een 0.5 m m ( 0.020 inc h ) and 1.0 m m ( 0.039 inc h ) , and 14.3% l onger th an 1.0 m m ( 0.039 inc h ) .

T h ese test resul ts ab out b y p ass rate and f ib rous deb ris siz e distrib ution are used f or inp uts of th e APR1400 in-vessel dow nstream ef f ec t tests.

T ab l e D.8-1 Cum ul ative Prototy p e B y p ass Deb ris Fib er added ( g/ l b m ) B y p assed f ib er w eigh t ( g/ l b m )

181.4 / 0.40 37.16 / 0.08 362.8 / 0.40 66.82 / 0.15 544.2 / 0.40 94.86 / 0.21 725.6 / 0.40 123.94 / 0.27 KEPCO & KHNP D15

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 T ab l e D.8-2 APR1400 B y p ass Deb ris Q uantities Pl ant Prototy p e Prototy p e strainer strainer Ratio of B y p assed Fl ow rate b y p ass Strainer Pum p s deb ris deb ris surf ac e f ib er m ass

( L / m in / gp m ) deb ris l oad l oad areas ( k g/ lb m )

( k g/ lb m ) *

( k g/ lb m ) ( k g/ lb m )

25,211 / 2.87 / 0.36 / 0.067 /

1 SIP+ CSP 8.0 0.54 / 1.18 6,660 6.33 0.79 0.1475 25,211 / 2.87 / 0.36 / 0.067 /

2 SIP+ CSP 8.0 0.54 / 1.18 6,660 6.33 0.79 0.1475 4,675 / 0.53 / 0.07 / 0.037 /

3 SIP 8.0 0.30 / 0.66 1,235 1.17 0.15 0.082 4,675 / 0.53 / 0.07 / 0.037 /

4 SIP 8.0 0.30 / 0.66 1,235 1.17 0.15 0.082 59,772 / 6.80 / 0.85 /

T otal 1.67 / 3.68 15,790 15.0 1.88

• Conversion f rom gram to l b m is 453 g/ l b m KEPCO & KHNP D16

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 D.9 REFERENCES 1-1 APR1400-E-A-T ( NR) -13003-P, " APR1400 IRW ST ECCS Sum p Strainer B y p ass T est Pl an," Rev. 1, KHNP, August 2013.

4-1 Saf ety Eval uation b y th e Of f ic e of Nuc l ear Reac tor Regul ation Rel ated to NRC Generic L etter 2004-02, Nuc l ear Energy Institute Guidanc e Rep ort ( Prop osed Doc um ent Num b er NEI 04-07) ,

" Pressuriz ed W ater Reac tor Sum p Perf orm anc e Eval uation M eth odol ogy ," Nuc l ear Energy Institute, Dec em b er 2004.

4-2 NU REG/ CR-6808, " Know l edge B ase f or th e Ef f ec ts of Deb ris on Pressuriz ed W ater Reac tor Em ergenc y Core Cool ing Sum p Perf orm anc e," U .S. Nuc l ear Regul atory Com m ission, Feb ruary 2003.

5-1 " Z OI Fib rous Deb ris Prep aration: Proc essing, Storage, and Handl ing," Nuc l ear Energy Institute, Revision 1 J anuary 2012.

6-1 Duk e Energy , " Path Forw ard f or Resol ution of GSI-191," M ay 2013.

7-1 " Q ual ity Assuranc e M anual ," Continuum Dy nam ic s, Inc ., Revision 14, Feb ruary 2006.

KEPCO & KHNP D17

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure D.2-1 Prototype Strainer in the T est T ank KEPCO & KHNP D18

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure D.2-2 Filter H ousings KEPCO & KHNP D19

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure D.2-3 Pump (on lef t), and Data Acq uisition Flow M eter/ DP Cells (on right)

KEPCO & KHNP D20

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure D.2-4 Flow Schematic of T est Setup KEPCO & KHNP D21

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure D.3-1 T est Strainer Draw ing KEPCO & KHNP D22

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure D.4-1 Aged Fib er Sample KEPCO & KHNP D23

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure D.4-2 Simulated Latent Deb ris Suspended in Water KEPCO & KHNP D24

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure D.5-1 T ypical Fib er Fine Addition KEPCO & KHNP D25

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure D.5-2 T est Facility Layout KEPCO & KHNP D26

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure D.5-3 Strainer Af ter T est and Drain Dow n KEPCO & KHNP D27

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure D.5-4 Strainer T ub e Inside Af ter T est and Drain Dow n KEPCO & KHNP D28

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure D.5-5 Detail of the Fib er Buildup Outside of the Fib er T ub e KEPCO & KHNP D29

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Figure D.6-1 T ime H istories of H ead Loss, Flow Rate, and T emperature KEPCO & KHNP D30

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 160 Fil ter # 29 Fil ter # 21 120 Prop ortion( p erm il )

80 40 0

0 1 2 3 L ength ( m m )

Figure D.6-2 Bypassed Fib er Length Distrib ution KEPCO & KHNP D31

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Appendix E Structural Drawings KEPCO & KHNP E1

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 Page intentionally blank KEPCO & KHNP E2

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.1 Reactor Containment Building Section A-A KEPCO & KHNP E3

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.2 Reactor Containment Building Section B-B KEPCO & KHNP E4

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.3 Reactor Containment Building-Concrete Outline Dimensional EL. 81-0 KEPCO & KHNP E5

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.4 Reactor Containment Building-Concrete Outline Dimensional EL. 100-0 KEPCO & KHNP E6

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.5 Reactor Containment Building-Concrete Outline Dimensional EL. 114-0 KEPCO & KHNP E7

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.6 Reactor Containment Building-Concrete Outline Dimensional EL. 136-6 KEPCO & KHNP E8

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.7 Reactor Containment Building-Concrete Outline Dimensional EL. 156-0 KEPCO & KHNP E9

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.8 Primary Shield Wall (Plan EL.69'-0")

KEPCO & KHNP E10

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.9 Primary Shield Wall (Plan EL.100'-0")

KEPCO & KHNP E11

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.10 Reactor & ICI Cavity Detail (Plan EL.69'-0")

KEPCO & KHNP E12

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.11 Primary Shield Wall (Plan EL.117'-4")

KEPCO & KHNP E13

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.12 Primary Shield Wall (Plan EL.130'-0")

KEPCO & KHNP E14

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.13 Primary Shield Wall (Plan EL.130'-0")

KEPCO & KHNP E15

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.14 Internal Structure (Plan EL.100'-0")

KEPCO & KHNP E16

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.15 Internal Structure (Plan EL.114'-0")

KEPCO & KHNP E17

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.16 Internal Structure (Plan EL.136'-6")

KEPCO & KHNP E18

Non-Proprietary Design Features to Address GSI-191 APR1400-E-N-NR-14001-NP, Rev.3 TS Figure E.17 Internal Structure (Plan EL.156'-0")

KEPCO & KHNP E17