ML16285A321
| ML16285A321 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 10/12/2016 |
| From: | Anderson M T NRC/NRR/DIRS/IPAB |
| To: | |
| Anderson M T,NRR/DIRS,301-415-8744 | |
| References | |
| Download: ML16285A321 (5) | |
Text
NRC Final Response FA Q 1 3-05 O y s t e r C r ee k Dow npo w e r March 17, 2014 P lan t: O y s t e r Cre e k Nucle ar Gener a ti n g Stat i o n D ate o f E v en t: 0 9/2 8/2 0 1 2 Sub m ittal Dat e: L ic en s e e C on t a c t: D en n is M M o o re T el/Emai l: 6 0 9-9 71-4 2 8 1 d en n is.m o o re@e x el o n c o r p.c o m NRC C on tact: Jeffr e y Ku l p T el/Emai l: 6 0 9-9 71-4 9 7 8 P er f o r m a n ce I nd ic a t o r: U N PL A N N E D P OW ER CHAN G E S P ER 7 , 0 0 0 CR ITIC A L H O URS (IE 0 3) S i t e-S pecific F A Q (A pp en d i x D)? N o F A Q req u es ted t o b e c o m e effe c t i ve: w he n a p p r o v ed. Qu esti o n Se ction NEI 99-0 2 Gu id a n ce n e ed in g inter pret a ti o n (i n clud e p a g e a n d li n e ci tati o n): P a ge 13 25 U npla nne d c ha n ge s in re ac t o r po w e r are c h a n g e s in r e ac t or p o we r t h at are i niti ated l e s s t h an 72 26 h o urs follo w i n g th e d i s co v ery of a n o f f-norm a l conditi on , a n d th at r es ult i n , o r r e quire a c h a n ge 27 in p o we r l e ve l of gr e a t e r t han 20% o f full p o we r to r e s ol v e. U npla nn e d c h a n g e s in r e ac t or p o we r 28 al s o i nclu d e un co n tr oll e d ex c u r sio n s o f g r e a t e r t h an 20% o f full p o we r t h at occur in r e s p o n s e t o 29 c h a n g e s in r e ac t or or pla n t co nd i tio n s an d are n ot an ex p ected part of a pla nn e d e v ol u ti o n o r te s t. P a ge 14 10 Equ i p me n t p r ob l em s e n co un t e r e d duri n g a pla nn e d p o we r r e duction grea t e r t h an 20% t h at alo n e 11 m ay h a v e r e quir e d a p o w e r r e duction o f 20% o r more t o r epair are n ot co unted a s part o f this 12 i ndicat o r if th e y are r e paired duri n g th e pla nn e d p o we r r e ductio n. H o we v er, if duri n g th e 13 i m p l e me n t a ti o n o f a pla nn e d p o we r r e ductio n , p o we r i s redu c e d b y more th an 20% o f f ull p o we r 14 b e y o n d th e pla nn e d r e ducti o n , th e n a n u npla nn e d p o we r c h a n ge h as occur r e d. E vent o r circ u mstan c es re q u ir in g g u i d a n ce i n t e r pret a ti o n: On Se p t e m b er 2 8 , , 2 0 1 2 a t 1 8 0 2- O y s t e r C r e e k Nucle ar Gener a ti n g Stat i o n (OC N G S) e x p er ienced an i ncrease in leaka g e f r o m a p re v i o u s l y ide ntified (<7 2 h o urs) sa l t w a t e r leak into t h e c ond en s er b a y f r om a h ole in circ ulati n g wa t er p i p i n g. The t i meli n e o f p o w er chang es and e vent de t ai ls are as f o l l o w s: 1 8 5 5 - C o n tr o l Roo m O p e r at o rs com m en ced l o w e ri n g p o w er t o al l o w is o l a ti n g a n d d ra in i n g o f the 1 A North C ond en s er w at e r bo x t o miti g a t e the le akage o f w a t e r i nto the c o n denser bay. 1 9 1 4 - GenMana g er T ic k et N u m b er 1 0 2 2 3 2 6 was c re a t e d t o t r a ck the emerge n t d own po w e r to 8 5%. The t i c k e t beg i n t i m e w as 1 9 0 1 with an end t i m e o f 2 2 5 9 (the t i ck e t w a s c rea ted, a s su c h, with t h e intent i o n o f merg i n g t h e rep a ir with the u p c o m i n g planned d own p o w er to 7 3%). 1 9 2 7 - T h e p o wer r ed ucti o n was c o m p le t e w ith R e a c t o r P o w e r at 8 5%. 1 9 4 3 - T h e 1 A North C o n denser wa t er b o x was i s o la te d r edu ci n g t h e leakage t o app r o xi m a t e ly h alf o f t h e i nitial leakage. 2 1 1 0 - Oper a ti o n s com m e nced dr a i n i n g 1A N orth wa terbox 2 1 4 7 - O perat i o n s c o m p le ted a pr e-j o b br i ef f o r l o w e r i n g r e ac t o r p o w e r t o 7 3% f o r "End o f Cycle R o d M a n e u v er s" NRC Final Response FA Q 1 3-05 O y s t e r C r ee k Dow npo w e r March 17, 2014 2 3 0 5 - C o n t r o l R o o m Ope r at o rs com m en ced l o w e ri n g p o w er f r o m 8 5% t o 73% f o r "End o f C ycle C o n t r o l R o d c onditi o n i n g m a n e u ver" (This is the beg i nn i n g o f a p lanned, >7 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in advanc e, d own po w e r to l o w e r p ower to 7 3% f r o m 9/28 , 2 3 0 0 u ntil 9/2 9, 0 7 0 0 ) 9/29 , 0 0 1 5 - C o n tr o l Roo m O pera t o rs c o m p le ted l o w e ri n g p o w e r t o 73%. 9/29 , 0 0 3 3 - C o n tr o l Roo m O pera t o rs com m en ced ra i si n g p o w e r f o r "E nd o f Cyc l e C o n tr o l R od c onditi o n i n g" 9/29 , 0 0 4 1 - The i n itial re p air t o t h e 1A N orth C ond e nser w a t e r b o x p i p i n g w as c o m p le te red u ci n g t h e le akage f r o m the w a t e r b o x t o ap p r o x i m a t e ly 1 g p m. 9/29 , 0 1 1 6 - A decis i o n w a s m a d e t o h o ld t h e p o w er ascension (with p o w e r a t 8 0%) to furt her assess the sa l t w a t e r leak prior t o r e t u r n i n g t o 1 0 0% p o w er 0 9/2 9 , 0 2 1 7 - O perat i o n s com p l e ted a pr e-j o b br i ef f o r l o weri n g p o w e r to 7 0% to aid in c o m pleting add it i o n al ci r c ulati n g w at e r pi p i n g r e p air to r ed u ce o r eli m i n a t e l e a k a g e. (7 0% was chosen to pr o v i d e m o re r e p air o p t i o n s) 0 9/2 9 , 0 3 0 2 - C o n t r o l Roo m O pera t ors com menced l o weri n g p o wer f r o m 8 0% t o 7 0% t o "Repa i r leak Ci r c W a t er L ea k" 0 9/2 9 , 0 3 3 5 - C o n t r o l Roo m O pera t ors c o m p le ted l o w e ri n g p o w e r to 7 0% 0 9/2 9 , 0 3 3 5 t o 0 9/2 9, 1 5 3 9 - OC NGS t o o k ac t i o n, as r equ ire d, t o aid in rep a ir in g t h e circ ulati ng wa t er lea k. 0 9/2 9 , 1 5 3 9 - Ci r cu lati n g w at e r repa irs are com p l e te a n d C o n t r o l R o o m Opera t o r s com m en ced ra i si n g r e ac t o r p o w er f r o m 7 0% t o 1 0 0% 0 9/2 9 , 1 8 4 3 - Reac t o r p o w er was r etur n ed t o 1 0 0% As n o ted ab o ve, O y st e r Cr e ek l o w e red p o w e r e merg e ntly (<7 2 h o urs) d u e t o a s alt w a t er l e a k- with an i nitial p o w er red u c ti o n to 8 5% (<2 0% r edu ct i o n). P o w er was t hen l o wered to 7 3% at 0 01 5 in ac c o r d a n ce with a p la nned (>7 2 h o urs) p o w e r m a n eu ver. A f t er c o m plet i o n o f t h e planned p o w e r m a n e u ver, d u ri ng p o w e r as cension (at app r o xi m a tely 8 0%) a decis i o n was m a d e t o l o w er po w e r to 7 0% p o w e r t o facili tate additi o nal rep airs t o t h e ci rculati n g w a t er s y st em to a t t em p t t o el i m i n a t e le akag e. 7 0% p o w er w a s chosen to all o w securi n g o f a circ ulati n g wa t er p u m p t o incre a se repa i r o p ti o ns. (It is i m p orta n t t o n ote that t h e r e p air c o u ld h a v e b e e n m a d e at a p o w e r l e v e l a b o v e 7 0%.) If l icens e e a nd NRC reside n t/reg i o n do n o t ag ree o n t h e facts and circ u mstan c es e xp l ai n: N RC Resident Comments The d es c ri p ti o n o f the e v e n t a n d su bseq uent pla n t r e s p o n se is ac c u ra t e as prese n t e d. The NRC reside n t i n s p ec t i o n s t aff do es n o t a g ree that the g u i d a n ce p rov i d ed in N EI 9 9-0 2 e x clud es t he durati o n o f a d own po w e r f r o m c o n si derat i o n w hen d e t e r m i n i n g w h ether a d o w np o w e r should c oun t a g ai n st th is per f o r m a n ce in dicat o r. NEI 9 9-0 2 r e v is i o n 6, pa g e 1 4, li n es 1 0-1 4 s t a t e: "Eq u i p m e n t p r o b l e m s e n coun t ered du ri n g a p lanned p o w er r e du ct i o n gr e at e r t h a n 2 0% that alo n e m a y ha v e req u i red a p o w e r r e du ct i o n o f 2 0% o r mo r e t o repa i r are n o t c o u n t e d as part o f th is in dicat o r if t h e y a r e r e p ai red d u ri n g t h e p la nned p o w e r redu ct i o n. Ho w e v e r, if d u ri n g t he i m p l e ment a ti o n o f a planned po w er r ed ucti o n , p o w e r is red uced b y m o re than 2 0% o f fu l l p o w e r be y o nd t h e p lann ed redu ct i o n, t hen an u np la nned po w er chang e h as oc c u rre d."
NRC Final Response FA Q 1 3-05 O y s t e r C r ee k Dow npo w e r March 17, 2014 The NRC reside n t i n s p ec t i o n s t aff d e t e r m i ned that t h i s d own p o w er s h o u ld c oun t f o r the f o ll owing reas o n s: The i nitial d own po w e r w as du e to ad dress an o f f-n o r m al c ond it i o n (t h e le a k o n t h e circ ulati ng wa t er pi p ing) a n d occur r ed ap p r o x i m a tely 4 h o urs be f o re scheduled p o w e r r edu c ti o n f o r c o n t r o l r o d c o nditi o n ing. The licen see r ed uced p ower by a t otal o f 3 0% t o per f o rm t h e rep a ir a n d r e s o l v e t h e eq u i pment p r o b le m. The eq u i pment p r o b l e m was n o t r e p ai red d u ri n g t h e p lanned pow e r r edu ct i o n. L ic en s e e P o s i t i o n An e merge n t d own p o w e r t o 8 5% w as in itia ted t o ad d ress circ u l a ti n g w a t er p i p i n g lea k. The e merge n t d own po w e r was scheduled t o c o i n ci d e w ith a plann ed d own p o w e r t o 7 3% f o r E n d o f C ycle R o d M a n eu vers (r o d pa t t e rn a d j u st m e n ts). Repa i rs c ommenced du ri n g t h e e merge n t d own p o w e r a nd c o n tinued i n t o t h e p lann ed p o w er red u c ti o n sign if i ca ntly red u ci n g the l eaka g e (t o ap p r o x i m a tely 1 gp m). T h e e m er gent d o w n p o w e r w as < 2 0 and t h e r e f o re o utside t h e s c o p e o f t h e p er f o r m a nce indicat o r. D u ri n g p o w er a scens i o n f r o m t h e p la nn ed p o w e r r ed ucti o n f o r r o d pat tern a d j u st ments, a decis i o n w a s m a d e to ha l t t h e po w e r as cension at 8 0%, red u ce p o w er t o 7 0%, a n d per f o r m a d diti o nal rep a irs to f urther red u ce o r e l i m i nate leakage fr o m the c i r cu lati n g w at e r pi p i n g r e p air prior to r e t u r n i n g t o 1 0 0% p o w e r. The po w e r red u ct i o n t o 7 0% was o utside o f t h e prep l anned e v o l u t i o n w hich en ded at 0 0 3 3 o n 9/2 9/1 2 The po w e r red u ct i o n t o 7 0% was < 2 0% b e l o w t h e pr e v i o u s p o w er l e v el o f 8 0% A p o w er red u c ti o n to 7 0% was no t req u i red f o r t h e a dditi o nal rep a irs P o w e r l e vel had n o t b een r es t ored t o 1 0 0% f o l l owing c o m plet i o n o f t h e plann ed p o w e r red ucti o n. P o t e ntial l y r e l e v a n t e x isti n g F A Q nu m ber s: N o n e R es ponse Se ction P r o p osed Re s o l u t i o n o f F A Q The e m er gent and pre p la n ned po w er red u c ti o n s h o u l d be e v al u at e d a s two po w er red u ct i o ns as opp o sed t o o n e c o n tinu o u s p o w er red u c ti o n to 7 3%. The po w e r red u ct i o n f r o m 8 0 to 7 0 s h o u ld n o t be c oun t e d as an u np lanned p o w er red u ct i o n sin c e it w as n o t >2 0% fr o m the prep l a nned o r t h e p r e v i o u s p o w e r l e vel. If app r o p ri a t e , pr o v i d e p rop osed r e w o r d i n g o f g u i d a n ce f o r i n cl u si o n in n e x t r e v i si o n.
NRC Final Response FAQ13*05 Oyster Creek Downpower March 17, 2014 Attachment 1- Reactor Power vs Time L o w=-r d P ow r d u: to ;1 3 in L o w:.r d p u t of : c o mm. m d r p o w:.r L O W H d p o w r d u: t o n:=d t o o o mp t=d Oi r c U l: tin.i t h Oi r c Ul t*ini W: t=-r s y s u.m (u r.p r.n d) p nn d (>i2 hour s) r o d p t t:.r n : dju s t m .n t d u: t o c o m p t i o n of r o d p t t:.r n : dju s t m .n t c o n t in u: Oi r c U l: tin.i w: w p i p: r p ir W H.r p i p: r p i r 00 r i: s.: d p o w:.r NRC Response The licensee is requesting interpretation of NEI 99
-02 guidance as applied to their particular donwpower event.
The current guidance in NEI 99
-02, Rev. 7 was incorporated by FAQ 469 (Sept. 2009) that changed the definition of unplanned power changes to the following:
NEI 99-02 Rev.7, P a ge 13 26 U np lann e d chang e s i n r e a c tor po w e r , for t he purpos e s of t h i s i nd i c a tor, ar e i s a c h a n g e s in 27 reac t o r po we r t h a t (1) a r e wa s i niti a t e d l e ss t h a n 72 hou r s f o ll o w i ng t he d i s c ov e r y of a n o f f- 28 no r m a l c onditi on t h a t re q u i re d or re su lt e d i n a p o we r c h a n g e , a nd t h a t re s u lt in, or re qui r e a 29 c h a n g e in po w er l e v e l o f g r ea te r t h a n 20% of f u l l po we r t o re so l v e , a nd (2) h a s not b ee n 30 e x c l ud e d fr om c oun ti ng p e r t he g u i d a n c e b e l o w. U np l a nn e d c h a n g e s i n r e ac t or po w e r a l so 31 i n c lude un c on t r o ll e d e x c u r s i ons of grea t e r t h a n 2 0% of f u l l po we r t h a t o cc u r i n response t o 32 c h a n g e s i n r eac t or o r p la nt conditions a nd ar e not a n e x p ec t e d p ar t o f a p la nn e d e vo l u ti on or t e s t.
NRC Final Response FAQ13*05 Oyster Creek Downpower March 17, 2014 The licensee concludes that the event should be excluded from counting as an Unplanned Power Change per 7,000 Critical Hours per the following guidance:
NEI 99-02, Rev. 7, P a ge 15 15 Equ i p me n t p r ob l em s e n co un t e r e d du ri n g a p la nn e d p o we r r e duction grea t e r t h an 20% t h at a lo n e 16 m ay h a v e r e qu ir e d a p o w e r r e duction o f 20% o r more t o r epair are n ot co unted a s part o f th is 17 i ndicat o r if th e y a re r e paired du ri n g th e p la nn e d p o we r r e ductio n. The NRC staff concludes that this event meets the first part of the definition of unplanned changes in reactor power since the down power was initiated less than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> following the discovery of a circulating water leak and resulted in a total power reduction of 30% (100% to 70%)
of full power to fully resolve.
The staff also concludes that the exclusion (NEI 99
-02, Rev. 7, page 15, lines 15
-17) does not apply based on the specific circumstances of the event, particularly because the equipment problem drove operators to lower power earlier than originally planned
. The staff's conclusion is that this event meets the guidance in NEI 99
-02, Rev. 7, as an Unplanned Power Change per 7,000 Critical Hours performance indicator occurrence.
The staff believes that the exclusion as written doesn't have sufficient detail on when an equipment problem should be counted toward the PI. The guidance (NEI 99
-02, Rev. 7, page 15, lines 15
-17) is difficult to apply because the intent is ambiguous (i.e., why is credit being granted when otherwise the occurrence by itself would count against the PI). The staff recommends modifying the guidance to provide a clear understanding of the basis for applying the guidance.
This FAQ is effective immediately after approval.