ML22039A340
| ML22039A340 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 02/08/2022 |
| From: | Kivi J Xcel Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML22039A342 | List: |
| References | |
| L-PI-22-004 | |
| Download: ML22039A340 (4) | |
Text
WE B-BAS ED P ROP OSE D AL TER NATIVE S UBMI SS ION 10 C FR 50.5 5 a( z)( 2)
Su bm issio n Da te: F e bru a ry 0 8, 2 02 2 Su bm itte d By : Ma ry Em a n u el son Doc u me n t S en sitiv it y: No n-S e nsi tiv e Lic e nse e : Xc e l En er gy Pla nt Uni t(s) a nd Do c ke t No(s): P ra irie Isl an d 2 (0 5 00 0 30 6 )
Lic e nse e Co nt ac t: Jeff Kiv i Jeff rey.L.Kiv i@ x ce l en e rg y. co m (61 2 ) 3 30-5 78 8
Pr oje c t T itle :
L-PI 0 04 P ra irie Isla nd Nu c le a r Ge n er at in g Pla n t Un it 2 1 0 CFR 5 0. 55 a Re q ue st No. RR -08, Re qu e st f or Alte rn at iv e to IS TC 36 3 0(f)
Pr op o se d Alt er n ati ve N um be r o r Id en tifi er :
RR-0 8
Req ue st Ty pe :
10 CF R 5 0.5 5a (z )(2 )
In se r vic e In spe c tio n (ISI) or Inse r vi ce Te sting (IS T)
Inse rv ic e Te sti ng (IS T)
Req ue ste d Co mp le tio n Da te :
Aug u st 1 8, 2 02 2
Br ie f De sc ri pti on o f P ro p ose d Alte r na tiv e Use an e v a lu at io n an d m o ni tor ing p la n fo r l ea k a ge p a st a pre ssu re iso la tio n v a lve (PIV) in li eu o f I STC-36 3 0( f) un til Un it 2 i s in a p la n ne d re fu e lin g o uta g e th a t i nc lu d es ve sse l de fu e lin g in o rde r to e ffe ct ua te a re pa ir or rep la c e m en t.
Pr op o se d Du r ati on o f Alt er n ati ve (in te rm s o f ISI/IS T P r og r am In te r va l w ith Sta r t a nd E nd Da te s):
Th e du ra tio n o f th is req u e st wil l c o nt in ue u n til th e v al ve c a n b e re pa ire d i n the ne x t p la n ne d Un it 2 re fue li ng ou ta g e in 2 02 3.
App lic a ble ASM E Co de Req ui r em e nts ISTA -33 0 0 - Co rre c tiv e a c tio ns re qu iri ng re p a ir/re p la c em e n t a c tiv it ie s sh al l b e p er form e d in a c c or da n ce with ASM E S e c tio n XI, as ap p lic a b le. Ot he r c o rre c tiv e a c tio ns sha ll b e pe rfo rm e d in a c c ord a nc e wi th th e Own e r's qu a lity a ssu ra nc e p ro gra m.I STC-36 3 0( e) - L ea k a ge ra t e m ea su re m en ts sha ll b e co m p a red wi th th e p er m issib le le ak a ge rat e s spe c ifi ed b y th e p la n t Own e r fo r a sp e c ific v a lv e o r v al ve co m b ina t ion. If l ea k a ge r at es ar e no t sp e c ifie d b y th e Own er, th e fo ll owin g ra te s sh a ll be p e rm issib le :(1 ) for wa te r, 0.5 D g a l/m i n (12.4 d m l/se c ) o r 5 ga l/m i n (31 5 m l/se c ), wh ic he v er is l e ss, a t fun c tio n p ressu re d iffe re n tia l(2 ) f or ai r, a t fu nc ti on p re ssur e dif fere n tia l, 7.5 D sta n d ard f t^3 /d a y (5 8d std. c c/ m in) wh er eD no m in a l v a lv e siz e, i n. d = no m in a l v a lv e siz e,
cm IS TC-36 3 0(f) - Va lv e s o r v a lv e c om b in at io ns with le a k ag e ra te s ex c e ed in g th e v al ue s sp e c ifie d b y th e Owne r pe r I STC-36 3 0(e ) sha ll b e de c la re d in o pe ra b le a nd b e e ith e r re p a ire d o r re p la ce d. A re te st d e m on stra ti ng ac c e pt ab le o p e rat io n sha ll b e pe rfo rm e d fo llo win g a ny re q ui re d co rre c tiv e a c tio n be fo re t he v a lv e is re t urn e d to se rv ic e.
App lic a ble Ame r ic a n So ci e ty of Me c ha n ic al En gin e e rs (ASM E) Boi le r a nd Pr e ssur e Ve sse l Co d e (BP V Cod e ), o r AS ME O pe r at ion a n d M a inte n an c eâ-o f Nuc le a r Po we r Pla n ts (O M Co de ), Edi tio n an d Add en da ASM E OM C od e 2 00 4, 2 0 06 A dd e nd a Cur r en t IS I o r IS T Pr o g ra m In te rv a l Nu m be r a nd S tar t/ End Da te s 5th I ST Int e rva l; sta rte d 1 2/ 21 /2 0 14 a n d sch e d ule d t o en d 1 2/ 20 /2 02 4
App lic a ble ASM E Co de Com p on e nts a n d/o r S yste m De sc r ip tio n Val ve : 2S I-6-4, 2 1 Ac cu m u la to r lo o p A c h ec k v a lv e do wn stre a m o f 2 SI-6-3 (se e fig u re in At ta ch m e nt 1 )
Sy ste m : S a fet y Inj ec t ion
Ca te go ry : A (Pro v id e iso la tio n b et wee n th e h ig h p ressu re Re a c to r Co o la nt S yste m ( RCS ) a nd t he low p ressu re Sa fe ty In je c tio n (SI) sy st e m; C (Ope n to p ro v ide flo w p at h fo r a c cu m u la to r Sa fe ty I nje c ti on )
Cla ss: 1
Rea so n for Re q ue st Re lie f re q ue st is b e in g sou g ht in th e e v e nt of a fo rc ed o u ta ge to d el ay re p a ir u n til th e n ex t pla n n ed r efu e lin g ou ta g e (2R 33 ) a s fix ing t he v a lv e re q uir es th e re ac to r to be de fu e le d an d d ra in ed.
Val ve 2 S I 4 is a c h ec k v a lv e in se rie s wi th c he c k v al ve 2 S I-6-3 be twe e n th e 2 1 Acc u m u la tor a nd t he R CS Lo op A Col d Le g to p ro te ct th e lo we r d e sig n pre ssu re Ac c um u la to r a n d a sso c ia te d p ip in g from th e hi gh e r RC S pre ssu re d uri ng n o rm al o pe ra tio n. V al ve 2 S I-6-4 is a n o n-t ec h ni ca l sp ec ifi ca t ion P IV w hic h i s te ste d p er IST C-36 30. NSP M se t t he l ea k a ge r at e ac c e p ta nc e c rit eri a fo r b ot h 2S I-6-3 a nd 2 SI-6-4 t o fiv e ga ll on s p e r m in u te usin g th e g e ne ric g u id a nc e o f IS TC-36 3 0(e ). Du rin g the 2R 32 re fu e lin g ou ta g e in Oc to b er 2 02 1, 2 SI 4 fa i le d the IST le a ka g e ra te te st ing p e rfo rm e d with a l ea k a ge ra te ap p ro xim a te d to b e 5.9 g a llo n s pe r m in ute.
Se rie s v a lv e 2S I-6-3 p asse d IS T l ea k a ge te stin g du rin g 2 R3 2, wit h a m ea su re d le a ka g e ra te o f 0.5 3 ga l lon s p e r mi nu te, whi ch i s th e lo we st p o ssib le le a k ra te th a t c a n b e in di ca te d d u e to c a lib ra te d flo w m e te r re stri c tio ns.
Ba se d o n d iv erse ind ic a tio n, t he a c tu a l 2 S I 3 le ak a ge was 0 ga ll on s p e r m in u te. T h ere fo re, the cu m u la tiv e cu rre n t m e a sure d le a k a ge fr om h ig h p re ssu re R CS to th e lo we r p re ssure ac c u m ula t or re pre se nt s m in-p at h le ak a ge an d e ffe c tiv e ly m on it ors th e le a ka g e fro m th e we ll pe rfo rm in g 2 SI-6-3 c h ec k v a lve. Fu rth e r, th er e is n o ex p ec te d d e gra d a tio n m e ch a n ism u nd e r wh ic h th e m in-p at h le a ka g e is e x pe c te d to c h a ng e d uri ng n o rm a l op e ra tio n sin ce t he va lv e s o nl y ch a ng e p o sitio n if th e RCS p re ssure i s b el ow th e a cc u m ul at or p ressu re. On th at ba sis, NSP M e va lu a te d th e im p a ct o f th e a s-fo un d le a k ag e ra te o f 2S I-6-4 on T ec h n ic al S pe c ific a ti on (T S) op e ra bil ity a n d de te rm in e d th a t it d id n ot im p ac t o pe ra b ilit y of th e 21 S I a c c um u la to r a n d Un it 2 wa s rest ar te d with ou t re pa iri ng 2 SI 4.
Th ere fo re, NSP M is p ro po sin g a n al te rna t ive to IST C-3 63 0 (f).
Ful l De sc r ipt ion o f P r op ose d Alte r n ati ve In lie u o f re p ai r o r re p la c em e n t o f 2 S I 4 for th e pe ri od o f re li e f, a m o n ito rin g p la n with th e a b ilit y to e va lu a te inc re a se d ac c u m ul at or le a ka g e will b e pe rfo rm e d. T his a lte rn at iv e will d em o n stra te th a t e v e n th ou g h 2S I-6-4 ha s e x c ee d e d its i nd iv id ua l IST le a k ag e ra te, th e m in-pa t h le ak a g e ra te to th e Ac c u mu la to r will be m a in ta in e d by 2 SI-6-3 wh ic h is cu rre n tly m e e tin g th e IS T P IV l ea k a ge r eq u ire m e nt.
Pla n t T S an d p roc e d ure s co n tro l m a in ta in in g a cc u m ul at or le v el a nd b o ron c o n ce n tra tio n. O pe ra b ilit y im pa c ts of ac c u mu la to r le ve l in cre a se wil l b e e v al ua te d a s p a rt o f t he c o rre c tiv e a c tio n pr og ra m wh ic h will id e nt ify a nd im pl em e n t a n y re qu ire d c o rre ct iv e ac t ion s. Ev a lua t ion s wi ll be d o c um e n te d an d re ta in e d in p la nt re c ord s a n d will be a v a ila b le fo r su b seq u en t re vie w.
Desc r ip tio n of Ba sis fo r Use Th e pro p ose d a lte rn a tiv e to t he r eq u ire m en ts of IST C-3 63 0 (f) p ro vi de s a n a c c ep ta b le le v e l o f q u a lity a n d sa fet y.
Th e co m b in at io n of th e le a k-t igh tn e ss o f th e 2 SI-6-3 a n d th e im p le m e nta ti on o f a n a d di tio na l e va lu a tio n a nd mo n ito rin g p la n will pr ov id e a h ig h le ve l of a ssura n c e th at d el a yin g th e re p ai r o r re p la c em e n t wi ll no t im pa c t op e ra bil ity.
With r esp e c t to t he 2 1 S I a c cu m u la to r o pe ra b ili ty:
- req u ire d b ora te d wa te r i n e ac h a c c um u la to r is 1 2 50 c u bi c fe et a n d 1 29 0 c u bi c fe et in a c c ord a nc e wi th TS Su rve il la nc e R eq u ire m e nt SR 3.5.1.2 ; a n d
- req u ire d b oro n c on c e nt rat io n in e ac h a c c um u la to r i s 2 3 00 p a rts pe r m i llio n in a c c ord a n ce w ith TS S R 3.5. 1. 4.
Ea ch a c c um u la to r i s v er ifie d to b e iso la te d a nd m o n ito re d e ve ry 1 2 ho u rs. An a dv e rse c on d iti on m o ni to rin g pla n (AC MP ) is c urre n tly i n pl ac e t o mo n ito r a n d lo g th e le ve l o f th e 2 1 SI ac c u m ul at or on c e p er shi ft u sin g th e ex isti ng p la n t su rv ei lla n ce pro c e du re. Th e site will fu rth er e va lu a te a n d use t he c o rre c tiv e a c tio n pro c e ss to mo n ito r a c c um u la to r b o ron c o n ce n tra tio n sh ou ld t he S I a c c um u la to r l ev e l r ise m or e th an 5 % in a da y. A 5 %
rise in o n e da y wo u ld be mu c h le ss th a n th e AS ME OM Co d e al lo wab le 5 ga llo n s p e r m in u te th a t th e P IV c h e ck va lv e is req u ire d to m e e t. Th er efo re, th e 5% r ise p er da y wo u ld c on se rv at ive l y trig ge r ad d iti on a l e n trie s i nt o th e co rre c tiv e a c tio n pr oc e ss, i nc lu d in g op e ra bi lity e v a lua t ion, in a dv a n ce of 2S I-6-3 de g ra da ti on e x c ee d in g ASM E al low ed l ea k a ge o f 5 gp m. I f le a ka g e is de te rm in e d to im p a c t o pe ra b ili ty, th e c o rre spo n din g T ec h ni ca l Sp ec i fic at io n Re qu ire d Ac ti on s wil l b e c o mp le te d a n d Uni t 2 wi ll b e sh u t d ow n in or de r t o co m p le te re p ai r o r rep la c e m en t.
NSP M pro p ose s t hi s a lte rn a tiv e to a llo w a pla n n ed r ep a ir o r rep la c e m en t of 2S I-6-4 to o c cu r whe n th e p la nt is in a sc he d ul ed r efu e lin g o ut ag e a s t he m a in te n a nc e o n th is v a lv e re qu ire s t he r ea c to r t o be d e fu el ed a n d th e RCS dra in e d. NS PM h a s c on c lu de d th a t thi s a lte rn a tiv e to d e fe r re p ai r o r re p la c em e n t o f 2 S I 4 whe n a p pro p ria te pla n t c o n dit io ns ca n b e e sta bl ish ed a s pa rt of a p la nn e d a nd sc h ed u le d e vo lu tio n p rov id e s a n a cc e p ta bl e le v el o f qu a lity a n d sa fet y be c a use :
- the ex isti ng l ea k a ge i s n ot im p a ct in g op e ra bil ity o f t he 2 1 S I a c cu m u la to r b ec a u se th e c u rre nt sta te o f 2 S I-6-4 ha s n o t re su lte d in a c c um u la to r i nle a k ag e d u e to n on-le a k ing c h e c k va lv e 2 SI 6-3 b e in g in se rie s ;
- ac c u mu la to r le ve l is b e in g reg u la rly m o ni to red a n d a sm a ll inc re a se in l ev e l i s wit hin t he ca p a bil ity o f l ev e l inst rum e n ta tio n to d e te c t a n d will be ad d re sse d wi th e xi stin g pro c e du re s;
- the ACMP i nc lu d es a le a ka g e ra te a c tio n th re sho ld t ha t is le ss tha n th e C od e a llo wa bl e le a ka g e o n 2S I-6-4; an d
- the re i s n o ex p e ct ed d e g rad a tio n m e c ha n ism u nd e r wh ic h le a k ag e i s e xp e c te d to ge t wo rse sin c e 2 SI-6-3 a n d 2S I-6-4 on ly c h an g e p osit io n in th e e ve n t R CS pr essu re fa ll s b el ow ac c u m ul at or pre ssu re.
Desc r ib e H ar d ship o r Un usu al Diff ic ulty Re pa iri ng 2 SI 4 wi ll req u ire t he re a c to r to b e d e fue le d a n d dra i ne d in o rd er to e sta b lish c o nd iti on s th a t are sa fe t o e ffe ct ua te r ep a ir, in cl ud in g th e e sta b lish m en t of do se le v e ls th a t m e e t ALARA (a s lo w a s re a so na b ly ac h ie va b le ) p rin c ip le s. M o vi ng a ll th e fu e l fro m t he re a c to r to t he sp e n t fu e l p o ol a nd d ra in in g th e re ac to r is reso u rc e in te nsi ve a n d a c om p le x e vo lu ti on. As su ch, ha rd sh ip or u nu sua l d iffic u lty wo u ld re sul t fro m co m p lia nc e wi th IS TC 36 3 0(f) be fo re t he n e xt p la nn e d Un it 2 r efu e lin g o ut ag e. Usin g the pro v isio ns of th is rel ie f re q ue st as a n al te rna ti ve to th e spe c ifi c re qu ire m e n ts o f IS TC-3 6 30 (f) id en ti fie d a bo v e will p rov id e ad e qu a te i nd ic a tio n o f a c cu m u la to r m in-p at hwa y p e rfor ma n c e a nd c o m pl ia nc e wi th IST C-3 63 0 (f) wo u ld h a ve no c o m pe n sat in g inc re a se in t he l ev e l o f safe ty o r qu a lity o v e r th e p rop o se d al te rna ti ve.
Any Ad dit io na l In fo rm a tio n (sub m issio n a tta c hm e nts liste d h er e )
2S I-6-4 an d se rie s v a lv e 2S I-6-3 a re P IVs th a t se p ar at e th e hi gh e r p re ssur e RCS fro m th e lo we r p re ssu re ac c u mu la to r. 2 SI-6-4 is no t a n E ve n t V PIV be c a use an y le a k ag e o f RC S ou t o f the 21 S I a c c um u la to r wo u ld b e insi de Un it 2 c on ta in m e nt.
1. Atta c h m en t 1. pd f
Pr ec e d en ts Non e
Refe r e nc e s
- 2. Te c hn ic a l Sp e ci fic a tio ns -Uni t 2