|
|
| (2 intermediate revisions by the same user not shown) |
| Line 2: |
Line 2: |
| | number = ML063390165 | | | number = ML063390165 |
| | issue date = 12/19/2006 | | | issue date = 12/19/2006 |
| | title = Vogtle Electric Generating Station (Vogtle), Unit 1 - Summary of Conference Call Regarding the 2006 Fall Outage Steam Generator Tube Inspections | | | title = (Vogtle), Unit 1 - Summary of Conference Call Regarding the 2006 Fall Outage Steam Generator Tube Inspections |
| | author name = Martin R M | | | author name = Martin R |
| | author affiliation = NRC/NRR/ADRO/DORL/LPLII-1 | | | author affiliation = NRC/NRR/ADRO/DORL/LPLII-1 |
| | addressee name = Grissette D E | | | addressee name = Grissette D |
| | addressee affiliation = Southern Nuclear Operating Co, Inc | | | addressee affiliation = Southern Nuclear Operating Co, Inc |
| | docket = 05000424 | | | docket = 05000424 |
| | license number = NPF-068 | | | license number = NPF-068 |
| | contact person = Martin R E, NRR/DORL, 415-1493 | | | contact person = Martin R, NRR/DORL, 415-1493 |
| | case reference number = TAC MD3371 | | | case reference number = TAC MD3371 |
| | document type = Letter, Meeting Summary | | | document type = Letter, Meeting Summary |
| Line 18: |
Line 18: |
|
| |
|
| =Text= | | =Text= |
| {{#Wiki_filter:De cembe r 19 , 20 06 M r. D. E. Gri ss e tt e Vi ce Pre si den t So uthe rn N ucl ear Operati ng Co mpan y , Inc.P.O. B o x 1 2 9 5Bi rmin gham, AL 35 201-129 5 | | {{#Wiki_filter:December 19, 2006 Mr. D. E. Grissette Vice President Southern Nuclear Operating Company, Inc. |
| | P.O. Box 1295 Birmingham, AL 35201-1295 |
|
| |
|
| ==SUBJECT:== | | ==SUBJECT:== |
| | VOGTLE ELECTRIC GENERATING PLANT, UNIT 1 (VOGTLE) - |
|
| |
|
| VOG T LE ELECTRI C GENERAT ING PLANT, UNIT 1 (VOG T LE) - SUM M ARY OF CONFERENCE CALL REGARDING THE 2006 FALL O UT AGE ST EAM GENE RA TO R TUBE IN SP EC TIO NS (TAC N O. M D3 371)De ar M r. Gris sette:On Octob er 1 8, 2 006 , the N ucl ear Re gula tory C ommis si on (NR C) staff pa rtic ip ated i n a con f eren ce cal l w ith S outh ern Nu cl ear Operati ng Co mpan y , Inc., rep rese ntati v es regardi ng ste am gen erat or inspect ion f inding s during the f all 2006 ref ueling outag e. T he NRC staf f is f orw ardi ng the en cl ose d s ummary for y our in f ormati on.
| | ==SUMMARY== |
| Sin ce r ely,/R A/
| |
| Ro bert M arti n, S eni or P roject M ana ger P l a n t L i ce n si n g B ra n ch I I-1 D i v i s i o n o f O p e r a t i n g R e a c t o r L i c e n s i n g Of f ic e o f N ucl ear Re acto r R egul ati on Do cket No. 50-424 E n cl o su re: Oc to b e r 1 8 C o n fere n ce C a l l S u mma ry c c w/e n c l: S e e n e x t p a ge De cembe r 19 , 20 06 M r. D. E. Gri ss e tt e Vi ce Pre si den t So uthe rn N ucl ear Operati ng Co mpan y , Inc.P.O. B o x 1 2 9 5Bi rmin gham, AL 35 201-129 5
| |
|
| |
|
| ==SUBJECT:== | | OF CONFERENCE CALL REGARDING THE 2006 FALL OUTAGE STEAM GENERATOR TUBE INSPECTIONS (TAC NO. MD3371) |
| | |
| | ==Dear Mr. Grissette:== |
| | |
| | On October 18, 2006, the Nuclear Regulatory Commission (NRC) staff participated in a conference call with Southern Nuclear Operating Company, Inc., representatives regarding steam generator inspection findings during the fall 2006 refueling outage. The NRC staff is forwarding the enclosed summary for your information. |
| | Sincerely, |
| | /RA/ |
| | Robert Martin, Senior Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-424 |
| | |
| | ==Enclosure:== |
| | |
| | October 18 Conference Call Summary cc w/encl: See next page |
| | |
| | ML063390165 NRR-106 OFFICE NRR/LPL2-1/PM NRR/LPL2-1/LA NRR/LPL2-1/BC NAME RMartin MOBrien EMarinos DATE 12 /11 /06 12 /18 /06 12 / 19 /06 OCTOBER 18, 2006, CONFERENCE CALL |
| | |
| | ==SUMMARY== |
| | |
| | STEAM GENERATOR TUBE INSPECTIONS VOGTLE ELECTRIC GENERATING PLANT, UNIT 1 DOCKET NO. 50-424 On October 18, 2006, the Nuclear Regulatory Commission (NRC) staff participated in a conference call with Southern Nuclear Operating Company, Inc., representatives, to discuss steam generator (SG) inspection activities at Vogtle Electric Generating Plant, Units 1 and 2, (Vogtle Unit 1 and Vogtle Unit 2), particularly those activities during the Vogtle Unit 1 fall refueling outage (designated 1R13). A summary of the information discussed during the call along with some background information is provided below. |
| | Vogtle Unit 1 has four model F SGs designed and fabricated by Westinghouse. Each SG contains 5626 thermally treated Alloy 600 tubes with an outside diameter of 0.688 of an inch and a nominal wall thickness of 0.040 of an inch. The tubes are hydraulically expanded for the full depth of the tubesheet at each end and are supported by a number of stainless steel tube supports. In the U-bend region, the tubes are supported by anti-vibration bars. The tubes are arranged in a square pitch. |
| | Vogtle Unit 1 SGs began commercial operation in 1987. In 2002, there was an inadvertent addition of phosphate to the Unit 1 and Unit 2 SGs. In the spring of 2004, Vogtle Unit 2 pulled two tubes to investigate crack-like indications at the expansion transition. A laboratory non-destructive examination of both of these tubes indicated that there was no cracking at the expansion transition. Destructive examination of one of these tubes confirmed there was no cracking at the expansion transition. In the spring of 2005, Vogtle Unit 1 identified cracking in bulges within the tubesheet. No crack-like indications were found during the fall 2005 inspection in Vogtle Unit 2. During the recently completed fall 2006 SG tube inspections at Vogtle Unit 1, crack-like indications were identified at the expansion transition. These findings are discussed below. The next Vogtle Unit 2 SG tube inspections are scheduled for the spring of 2007. |
| | During the 1R13 outage, 100 percent of the tubes in SGs 2 and 3 were inspected with a bobbin coil. In addition, the U-bend region of 50 percent of the row 1 and 2 tubes, and 100 percent of the dings and dents greater than 5 volts in the hot leg in SGs 2 and 3 were inspected with a rotating probe. The SGs were chemically cleaned before the tube inspections and the SGs operate at a hot leg temperature of 618 o F. |
| | During 1R13, +Point' inspections of the top of the tubesheet region were planned for 50 percent of the tubes in SGs 2 and 3. During this initial sample, indications of outside diameter stress corrosion cracking were found in several tubes at the bottom of the expansion transition region in both SGs. As a result of finding these indications, the scope of inspection at the top of the tubesheet was expanded to include 100% of the tubes in SGs 2 and 3 and 25 percent of the tubes in SGs 1 and 4. The extent of this inspection was from 3 inches above to 3 inches Enclosure |
| | |
| | below the top of the tubesheet. As a result of finding indications in the initial sample inspection in SGs 1 and 4, the scope of the inspection at the top of the tubesheet was expanded to include 100 percent of the tubes. At the time of the conference call, 10 indications had been identified: |
| | 3 in SG 1, 2 in SG 2, 3 in SG 3, and 2 in SG 4. The licensee indicated that evaluations for other possible indications, some in the sludge pile region, were still ongoing in SG 4. |
| | For SGs 1, 2 and 3, the indications are predominantly located in low row, high column tubes along the periphery (between rows 1 through 6 and between columns 103 through 119). |
| | In order to confirm the indications, five different inspection methods were used: +Point', |
| | Ghent, 3 Coil Delta, and the 0.080 and 0.115 pancake coil. All of the inspection methods confirmed the indications with the exception that some of the small amplitude signals were not identified with the 0.080 pancake coil. Given these results, the licensee concluded that these indications are cracks. |
| | The largest crack-like indication was measured to have a circumferential extent of 180 degrees. |
| | The maximum reported depth was 67 percent throughwall. The indication with the largest circumferential extent was not the same indication that had the maximum depth. The voltages associated with the indications were approximately 0.2 volts, although there were two indications that had voltages of 0.60 volts and 0.73 volts. A historical review of the +Point' data for the tubes in which the ODSCC indications were detected this outage was performed. |
| | This review did not identify any precursor signals in these tubes. |
| | The licensee stated that it had alerted the industry (other licensees of pressurized-water reactors) regarding this issue. |
| | All tubes with crack-like indications will be plugged and stabilized. The licensee considered pulling a tube or tubes, but due to a major tube-pull project overseas, the licensee was not able to pull a tube given its outage schedule. The licensee will evaluate pulling a tube during the next refueling outage. Due to the location of the tubes with crack-like indications in relation to the divider plate, it is not clear whether pulling a tube is feasible. With respect to similar operating experience, the licensee indicated that Comanche Peak Unit 1 had first detected outside diameter circumferential cracks in a similar region of the tube bundle. |
| | The licensee also stated there were indications near the top of the tubesheet that were identified with the +Point' probe but not confirmed with the Ghent, 3 Coil Delta probe or the 0.080 coil. These indications had voltages of approximately 0.06 volts to 0.08 volts. |
| | In addition to crack-like indications found during the inspection, a volumetric flaw above the cold leg flow distribution baffle measuring 42 percent through-wall was detected in one tube. |
| | The indication was attributed to a loose part. +Point' inspections were performed at this elevation for a 2-tube buffer surrounding this volumetric flaw. No possible loose parts were identified during this inspection. Given the location of the indication, visual inspections could not be performed. Other volumetric indications were observed in SG 2, however, they measured less than 10-percent through-wall. |
| | Inspections were performed on a sample of bulges and overexpansion in the tubesheet region (i.e., from the top of the tubesheet to 17 inches below the top of the secondary face of the tubesheet). No indications were found during these inspections. |
| | Based on the information provided, the NRC staff did not identify any technical issues that warranted follow-up action at this time. |
|
| |
|
| VOG T LE ELECTRI C GENERAT ING PLANT, UNIT 1 (VOG T LE) - SUM M ARY OF CONFERENCE CALL REGARDING THE 2006 FALL O UT AGE ST EAM GENE RA TO R TUBE IN SP EC TIO NS (TAC N O. M D3 371)De ar M r. Gris sette:On Octob er 1 8, 2 006 , the N ucl ear Re gula tory C ommis si on (NR C) staff pa rtic ip ated i n a con f eren ce cal l w ith S outh ern Nu cl ear Operati ng Co mpan y , Inc., rep rese ntati v es regardi ng ste am gen erat or inspect ion f inding s during the f all 2006 ref ueling outag e. T he NRC staf f is f orw ardi ng the en cl ose d s ummary for y our in f ormati on.
| | Vogtle Electric Generating Plant, Units 1 & 2 cc: |
| Sin ce r ely, /RA/
| | Mr. Laurence Bergen Mr. D. E. Grissette, Vice President Oglethorpe Power Corporation Southern Nuclear Operating Company, Inc. 2100 East Exchange Place P.O. Box 1295 P.O. Box 1349 Birmingham, AL 35201-1295 Tucker, GA 30085-1349 Mr. N. J. Stringfellow Arthur H. Domby, Esquire Manager, Licensing Troutman Sanders Southern Nuclear Operating Company, Inc. Nations Bank Plaza P.O. Box 1295 600 Peachtree Street, NE Birmingham, AL 35201-1295 Suite 5200 Atlanta, GA 30308-2216 Mr. T. E. Tynan, General Manager Vogtle Electric Generating Plant Resident Inspector Southern Nuclear Operating Company, Inc. Vogtle Plant 7821 River Road 8805 River Road Waynesboro, GA 30830 Waynesboro, GA 30830 Mr. Jeffrey T. Gasser Office of the County Commissioner Executive Vice President Burke County Commission Southern Nuclear Operating Company, Inc. Waynesboro, GA 30830 P.O. Box 1295 Birmingham, AL 35201-1295 Mr. Steven M. Jackson Senior Engineer - Power Supply Municipal Electric Authority of Georgia 1470 Riveredge Parkway, NW Atlanta, GA 30328-4684 Mr. Reece McAlister Executive Secretary Georgia Public Service Commission 244 Washington St., SW Atlanta, GA 30334 Mr. Harold Reheis, Director Department of Natural Resources 205 Butler Street, SE, Suite 1252 Atlanta, GA 30334 Attorney General Law Department 132 Judicial Building Atlanta, GA 30334}} |
| Ro bert M arti n, S eni or P roject M ana ger P l a n t L i ce n si n g B ra n ch I I-1 D i v i s i o n o f O p e r a t i n g R e a c t o r L i c e n s i n g Of f ic e o f N ucl ear Re acto r R egul ati on Do cket No. 50-424 En cl osu re: Oc to b e r 1 8 C o n fere n ce C a l l S u mma ry c c w/e n c l: S e e n e x t p a ge DIST RIBUT IO N:P U B L IC P D II-1 R/FR i d sN rr L A M O'B ri e n R i d sN rr D o rl L p l 2-1 (E M a ri n o s) Ri dsOGCR p Ri dsA crsA cnw M ai lC ente rNrr DciCsg b(YDiaz-Cast ill o)
| |
| RidsNrr PM RM art in R i d sR gn2 M a i l C tr (S S h a e ff e r) AD AM S Acc ess io n N o.: M L06 339 016 5 NR R-1 06 OF FICE NRR/LPL2-1/PM NRR/LPL2-1/LA NRR/LPL2-1/BC NA M E RM arti n M O'B rie n EM ari nos DA TE 12 /11 /06 12 /18 /06 12 / 1 9 /0 6 OFFICIAL RECORD CO PY Enclo sure OCT OBER 18, 2006, CO NFERENCE CALL SUM M ARY ST EAM GENERAT OR T UBE INSPECT IO NS V OG TL E E L E C TR I C G E N E R A TI N G P L A N T, U N I T 1 DOCK ET N O. 50-4 24 On Octob er 1 8, 2 006 , the N ucl ear Re gula tory C ommis si on (NR C) staff pa rtic ip ated i n a con f eren ce cal l w ith S outh ern Nu cl ear Operati ng Co mpan y , Inc., rep rese ntati v es, to d is cus s stea m genera tor (S G) i nsp ecti on acti v iti es at V ogtle E le ctri c Gen erati ng Pl ant, Un its 1 and 2, (Vog tle Unit 1 and Vogt le Uni t 2), part icularly thos e activities during the Vog tle Unit 1 f all ref ueling outag e (desig nate d 1R13). A summ ary of the inf orm ation discus sed dur ing the call a lo n g wit h so m e ba c k g r o u n d in f o r m a t io n is pr o vi d e d be lo w.Vog tle Unit 1 has f our m odel F SGs desig ned and f abrica ted by W est ing house. Each SG con tai ns 562 6 th ermal ly trea ted Al lo y 60 0 tu bes w ith an ou tsi de di ameter of 0.688 of an i nch and a nomi nal w al l thi ckness of 0.040 of an i nch. The tub es are hy drau li cal ly ex pan ded for the f ul l dep th o f the tub esh eet at e ach en d a nd are sup porte d b y a numb er o f sta in le ss stee l tube su p p o rt s. In t h e U-b e n d r e gi o n , th e t u b e s a re s u p p o rt e d b y a n ti-v i b ra ti o n b a rs. Th e t u b e s a re arran ged i n a square pi tch.Vo gtle Un it 1 S Gs be gan co mmerci al op erati on in 19 87. In 200 2, th ere w as an in adv erten t add iti on of pho sph ate to th e U ni t 1 and U ni t 2 SGs. In the spri ng of 200 4, V ogtle U ni t 2 pul le d tw o tu bes to in v esti gate cra ck-li ke i ndi cati ons at the ex pan si on trans iti on. A l abo ratory no n-des tructi v e e x ami nati on of both of these tub es in di cate d th at th ere w as no crac king at the ex pan si on trans iti on. D estru cti v e e x ami nati on of one of the se tube s c onfirmed the re w as no cra ck ing at the expansion tra nsition. In th e spring of 2005, Vog tle Unit 1 identif ied crack ing in bul ges w ith in the tub esh eet. N o c rack-li ke i ndi cati ons w ere f oun d d uri ng the fall 20 05 in spe cti on in V ogtle U ni t 2. D uri ng the rec entl y co mpl eted fall 20 06 SG tu be in spe cti ons at V o gt l e U n i t 1 , c r a c k-l i ke i n d i c a t i o n s w e r e i d e n t i fi e d a t t h e e x p a n s i o n t r a n s i t i o n. Th e s e fi n d i n gs are di scu sse d b el ow. The ne x t V ogtle U ni t 2 SG tu be in spe cti ons are sc hed ul ed f or th e spri ng of 200 7.During the 1R13 outag e, 100 per cent of the tube s in S Gs 2 and 3 w ere inspec ted wi th a bobbin coi l. In add iti on, the U-b end regi on of 50 perc ent of the row 1 and 2 tube s, a nd 100 pe rcen t of the di ngs an d d ents greate r tha n 5 v ol ts i n th e h ot l eg i n S Gs 2 and 3 w ere in spe cted w ith a ro ta ti n g p ro b e. Th e S Gs w e re c h e mi ca l l y c l e a n e d b e fore t h e t u b e i n sp e ct i o n s a n d t h e S Gs ope rate at a ho t l eg tempe rature of 61 8 F. o Du rin g 1R1 3, +P oi ntŽ i nsp ecti ons of the top of the tub esh eet regio n w ere pl ann ed f or 5 0 perc ent of the tube s i n S Gs 2 and 3. D uri ng thi s i ni tia l sampl e, i ndi cati ons of ou tsi de di ameter stress co rrosi on crac king w ere f oun d i n s ev eral tub es at th e b ottom o f the ex pan si on trans iti on regio n i n b oth SGs. A s a res ul t of f in di ng the se in di cati ons , the sc ope of i nsp ecti on at the top of the tube she et w as ex pan ded to in cl ude 10 0% o f the tub es in S Gs 2 and 3 and 25 pe rcen t of the tube s i n S Gs 1 and 4. The ex tent of thi s i nsp ecti on w as f rom 3 i nch es abo v e to 3 in che s bel ow the top of the tub esh eet. A s a res ul t of f in di ng i ndi cati ons i n th e i ni tia l sampl e i nsp ecti on in S Gs 1 and 4, the sco pe of the in spe cti on at th e to p o f the tub esh eet w as ex pan ded to in cl ude 100 pe rcen t of the tube s. At the time of the co nference ca ll , 10 i ndi cati ons ha d b een i den tifie d: 3 i n S G 1, 2 i n S G 2, 3 i n S G 3, and 2 in S G 4. The li cen see i ndi cate d th at e v al uati ons for othe r po ssi bl e i ndi cati ons , so me i n th e s lu dge p il e re gion , w ere sti ll on goin g in S G 4.For SGs 1, 2 an d 3 , the i ndi cati ons are pre domi nan tly l oca ted in l ow row , hi gh col umn tube s a l o n g th e p e ri p h e ry (b e tw e e n r o w s 1 t h ro u gh 6 a n d b e tw e e n c o l u mn s 1 0 3 t h ro u gh 1 1 9).In o rder to c onfirm th e i ndi cati ons , fiv e d iff eren t i nsp ecti on method s w ere use d: +P oi ntŽ, Ghent, 3 C oi l De lta , an d th e 0.080 an d 0.115 pa nca ke coi l. A ll of the i nsp ecti on method s con f irme d th e i ndi cati ons w ith the ex cep tio n th at s ome of the smal l ampl itu de si gnal s w ere not id enti f ie d w ith the 0.0 80 pan cake c oi l. Gi v en thes e re sul ts, th e l ic ens ee con cl ude d th at th ese i n d i ca ti o n s a re c ra cks. The l argest c rack-li ke i ndi cati on w as measu red to h av e a ci rcumferenti al ex tent of 180 de grees.The max imu m rep orted de pth w as 67 perc ent throu ghw al l. The in di cati on w ith the l argest ci rcumferenti al ex tent w as not the same in di cati on that had the max imu m de pth. The v ol tages a s s o c ia t e d wit h t h e in d ic a t io n s wer e ap p r o xi m a t e ly 0.2 vo lt s , al t h o u g h t h e r e wer e t wo i n d i ca ti o n s th a t h a d v o l ta ges o f 0.6 0 v o l ts a n d 0.7 3 v o l ts. A h i st o ri ca l r e v i e w o f th e +P o i n tŽd a ta for t h e t u b e s i n w h i ch t h e OD S C C i n d i ca ti o n s w e re d e te ct e d t h i s o u ta ge w a s p e rfor me d. This rev ie w di d n ot i den tify an y pre curs or s igna ls i n th ese tub es. The l ic ens ee state d th at i t ha d a le rted the in dus try (oth er l ic ens ees of pre ssu riz ed-w ater re a ct o rs) re gar d i n g th i s i ss u e. Al l tube s w ith cra ck-li ke i ndi cati ons w il l be pl ugg ed and sta bi li z ed. The li cen see co nsi dere d pulling a tube or tubes, but due to a maj or tu be-p ull proj ect ov ers eas, the licensee w as not able to p ul l a tu be giv en its ou tage sc hed ul e. The l ic ens ee w il l ev al uate pu ll in g a tu be duri ng the n e x t re fue l i n g o u ta ge. D u e t o t h e l o ca ti o n o f th e t u b e s w i th c ra ck-l i ke i n d i ca ti o n s i n r e l a ti o n t o the di v id er p la te, i t i s n ot c le ar w heth er p ul li ng a tube i s feasi bl e. W ith res pec t to si mil ar ope rati ng ex peri enc e, th e l ic ens ee in di cate d th at C oman che P eak U ni t 1 had first d etec ted outs id e d ia meter c irc umf eren tia l crac ks in a si mil ar re gion of the tub e b und le.The l i ce n se e a l so s ta te d t h e re w e re i n d i ca ti o n s n e a r th e t o p o f th e t u b e sh e e t th a t w e re id enti f ie d w ith the +P oi ntŽ p robe bu t no t co nfirmed w ith the Ghe nt, 3 C oi l De lta pro be or th e 0.08 0 c oi l. Thes e i ndi cati ons ha d v ol tages o f ap prox ima tel y 0.0 6 v ol ts to 0.0 8 v ol ts.In addit ion to crac k-lik e indications f ound dur ing the inspect ion, a v olume tr ic f law above the cold le g f lo w di stri buti on baff le mea suri ng 42 pe rcen t thro ugh-w al l w as dete cted i n o ne tube.T he indication w as att ribut ed to a loose part. +PointŽ inspections w ere per f orm ed at this e l e v a ti o n for a 2-t u b e b u ff e r su rr o u n d i n g th i s v o l u me tr i c fla w. N o p o ss i b l e l o o se p a rt s w e re identif ied during this inspect ion. Given the location of the indication, v isual i nspec tions could not be performed.
| |
| Other v ol umetri c i ndi cati ons w ere obs erv ed in S G 2, how ev er, th ey me asur ed less than 10-perc ent t hrou g h-wall.Insp ecti ons w ere performed on a s ampl e o f bu lges and ov erex pan si on in the tub esh eet regio n (i.e., from the top of the tube she et to 17 i nch es bel ow the top of the se con dary face o f the tube she et). No i ndi cati ons w ere f oun d d uri ng the se in spe cti ons.Ba sed on the i nformatio n p rov id ed, the NR C staff di d n ot i den tify an y tec hni cal i ssu es that w arran ted f ol lo w-up acti on at th is ti me.
| |
| Vog tle Electr ic Gener ating Plant, Units 1 & 2 cc: M r. D. E. Gri sse tte, V ic e P resi den t So uthe rn N ucl ear Operati ng Co mpan y , Inc.P.O. B ox 12 95 Bi rmin gham, AL 352 01-1 295 M r. N. J. Stri ngf el lo w M ana ger, Li cen si ng So uthe rn N ucl ear Operati ng Co mpan y , Inc.P.O. B ox 12 95 Bi rmin gham, AL 35 201-129 5M r. T. E. Tyn an, Genera l M ana ger Vo gtle El ectri c Gen erati ng Pl ant So uthe rn N ucl ear Operati ng Co mpan y , Inc.782 1 R iv er R oad W ay nes boro , GA 30 830 M r. Je f f rey T. Gasse r Ex ecu tiv e V ic e P resi den t So uthe rn N ucl ear Operati ng Co mpan y , Inc.P.O. B ox 12 95 Bi rmin gham, AL 352 01-1 295 M r. S tev en M. Ja ckson Senior Eng ineer - Power Supply M unicipal El ect ric Autho rity of Geor g ia 1470 Riv ered g e Park w ay, NW Atl anta , GA 30 328-468 4 M r. R eec e M cAl is ter E x e cu ti v e S e cr e ta ry Georgia P ubl ic S erv ic e C ommis si on 244 W ashing ton St., SW Atl anta , GA 30 334 M r. H arol d R ehe is , D ire ctor De partmen t of Na tural R eso urce s 205 B utl er S treet, SE , S ui te 1 252 Atl anta , GA 30 334 Attorn ey Gen eral Law D epa rtment 132 Ju di ci al B ui ld in g Atl anta , GA 30 334 M r. La uren ce Be rgen Og le thorp e P ow er C orpo rati on 210 0 E ast Ex cha nge P la ce P.O. B ox 13 49 Tucker, GA 300 85-1 349 A rt h u r H. D o mb y , E squ i re Tro u tma n S a n d e rs Na t ion s Ba nk Pla za 600 Peacht ree St reet , NE Su ite 52 00 Atl anta , GA 30 308-221 6 Re si den t Ins pec tor Vo gtle Pl ant 880 5 R iv er R oad W ay nes boro , GA 30 830 Of f ic e o f the C oun ty C ommis si one r Bu rke Co unty C ommis si on W ay nes boro , GA 30 830}}
| |
Letter Sequence Other |
|---|
|
|
MONTHYEARML0633901652006-12-19019 December 2006
(Vogtle), Unit 1 - Summary of Conference Call Regarding the 2006 Fall Outage Steam Generator Tube Inspections
Project stage: Other
2006-12-19
[Table View] |
|
|---|
Category:Letter
MONTHYEARML24297A6482024-10-23023 October 2024
5 to the Updated Final Safety Analysis Report, Technical Specification Bases Changes, Technical Requirements Manual Changes, Summary Report and Revised NRC Commitments Report
ML24269A2502024-09-26026 September 2024
Acknowledgement of the Withdrawal of the Requested Exemption and License Amendment Request to Remove Tier 1 and Tier 2* Requirements
NL-24-0350, Core Operating Limits Report, Cycle 24, Version 22024-09-25025 September 2024
Core Operating Limits Report, Cycle 24, Version 2
NL-24-0369, Withdrawal of License Amendment Request and Exemption Request: Remove Tier 1 and Tier 2 Requirements2024-09-25025 September 2024
Withdrawal of License Amendment Request and Exemption Request: Remove Tier 1 and Tier 2 Requirements
ML24243A0072024-09-10010 September 2024
– Correction of Amendment Nos. 223 and 206 Regarding Revision to Technical Specifications to Adopt TSTF-339-A, Relocate Technical Specification Parameters to the COLR Consistent with WCAP-14483
NL-24-0337, Interim 10 CFR 21.21(a)(2) Report Regarding Operation Technology, Inc., ETAP Software Error in Transient Stability Program2024-09-0909 September 2024
Interim 10 CFR 21.21(a)(2) Report Regarding Operation Technology, Inc., ETAP Software Error in Transient Stability Program
ML24102A2642024-09-0909 September 2024
– Exemption Request Regarding Final Safety Analysis Report Update Schedule (EPID L-2024-LLE-0013) - Letter
ML24249A2942024-09-0606 September 2024
Correction of Amendment Nos. 218 and 201 Regarding Revision to Technical Specifications to Use Online Monitoring Methodology
05200025/LER-2024-002, Manual Reactor Protection System and Automatic Safeguards Actuation Due to an Unexpected Change in Position of a Main Feedwater Pump Minimum Flow Control Valve2024-09-0505 September 2024
Manual Reactor Protection System and Automatic Safeguards Actuation Due to an Unexpected Change in Position of a Main Feedwater Pump Minimum Flow Control Valve
IR 05000424/20240052024-08-26026 August 2024
Updated Inspection Plan for Vogtle Electric Generating Plant, Units 1 and 2 - Report 05000424/2024005 and 05000425/2024005
ML24235A1952024-08-22022 August 2024
Updated Inspection Plan for Vogtle Electric Generating Plant, Units 3 and 4 - Report 05200025/2024005 and 05200026/2024005
IR 05000424/20244012024-08-15015 August 2024
4 - Security Baseline Inspection Report 05000424-2024401, 05000425-2024401, 05200025-2024402, and 05200026-2024403 - Cover Letter
NL-24-0299, Exemption Request: Final Safety Analysis Report Update Schedule, Response to Request for Additional Information2024-08-14014 August 2024
Exemption Request: Final Safety Analysis Report Update Schedule, Response to Request for Additional Information
05000425/LER-2024-001, Manual Actuation of the Reactor Protection System Due to a Rod Control Fuse Opening Causing a Misaligned Shutdown Rod2024-08-0909 August 2024
Manual Actuation of the Reactor Protection System Due to a Rod Control Fuse Opening Causing a Misaligned Shutdown Rod
ML24218A1842024-08-0707 August 2024
Examination Report and Cover Letter
05200026/LER-2024-001, Manual Reactor Protection System Actuation Due to Procedure Not Optimally Sequenced to Reset the Rapid Power Reduction Signal2024-08-0606 August 2024
Manual Reactor Protection System Actuation Due to Procedure Not Optimally Sequenced to Reset the Rapid Power Reduction Signal
ML24212A1442024-08-0101 August 2024
Integrated Inspection Report 05200025/2024002 and 05200026/2024002
IR 05000424/20240022024-07-29029 July 2024
Integrated Inspection Report 05000424/2024002 and 05000425/2024002
IR 05000424/20244042024-07-26026 July 2024
Material Control and Accounting Program Inspection Report 05000424/2024404 and 05000425/2024404 (Cover Letter)
NL-24-0282, License Amendment Request and Exemption Request: Remove Tier 1 and Tier 2* Requirements2024-07-25025 July 2024
License Amendment Request and Exemption Request: Remove Tier 1 and Tier 2* Requirements
NL-24-0126, – Units 3 and 4, License Amendment Request: Changes to Technical Specification 3.7.6, Main Control Room Emergency Habitability System (Ves) Action a and SR 3.7.6.62024-07-25025 July 2024
– Units 3 and 4, License Amendment Request: Changes to Technical Specification 3.7.6, Main Control Room Emergency Habitability System (Ves) Action a and SR 3.7.6.6
ML24204A0722024-07-23023 July 2024
Issuance of Amendment No. 225, Regarding LAR to Revise TS 3.7.9 for a one-time Change to Support Nuclear Service Cooling Water Transfer Pump Repairs - Emergency Circumstances
NL-24-0286, Emergency Request to Revise Technical Specification 3.7.9 for a One-Time Change to Support a Unit 1 Nuclear Service Cooling Water Transfer Pump Repair2024-07-20020 July 2024
Emergency Request to Revise Technical Specification 3.7.9 for a One-Time Change to Support a Unit 1 Nuclear Service Cooling Water Transfer Pump Repair
ML24191A4562024-07-19019 July 2024
Request for Relief and Alternative Requirements for Squib (Explosively Actuated) Valves First Test Interval
NL-24-0261, 10 CFR 50.46 ECCS Evaluation Model Annual Report for 20232024-07-19019 July 2024
10 CFR 50.46 ECCS Evaluation Model Annual Report for 2023
ML24194A0342024-07-12012 July 2024
Review of the Refueling Outage 1R24 Steam Generator Tube Inspection Report
ML24191A3792024-07-10010 July 2024
– Initial Test Program and Operational Programs Inspection Report 05200026/2024011
NL-24-0227, Proposed Inservice Inspection Alternative GEN-ISI-AL T-2024-03 for Pressurizer Welds in Accordance with 10 CFR 50.55a(z)(1)2024-07-0303 July 2024
Proposed Inservice Inspection Alternative GEN-ISI-AL T-2024-03 for Pressurizer Welds in Accordance with 10 CFR 50.55a(z)(1)
NL-24-0234, Application to Revise Technical Specifications to Adopt TSTF-589, Eliminate Automatic Diesel Generator Start During Shutdown2024-06-28028 June 2024
Application to Revise Technical Specifications to Adopt TSTF-589, Eliminate Automatic Diesel Generator Start During Shutdown
NL-24-0143, Proposed Alternative to Use ASME Code Case N-752, Risk-Informed Categorization and Treatment for Repair/ Replacement Activities in2024-06-27027 June 2024
Proposed Alternative to Use ASME Code Case N-752, Risk-Informed Categorization and Treatment for Repair/ Replacement Activities in
NL-24-0087, License Amendment Request: Changes to Technical Specification 3.7.6, Main Control Room Emergency Habitability System (Ves) Air Storage Tanks2024-06-21021 June 2024
License Amendment Request: Changes to Technical Specification 3.7.6, Main Control Room Emergency Habitability System (Ves) Air Storage Tanks
NL-24-0201, Proposed Inservice Inspection Alternative GEN-ISI-ALT-2024-002 for Steam Generator Welds in Accordance with 10 CFR 50.55a(z)(1)2024-06-18018 June 2024
Proposed Inservice Inspection Alternative GEN-ISI-ALT-2024-002 for Steam Generator Welds in Accordance with 10 CFR 50.55a(z)(1)
NL-24-0243, Registration of Spent Fuel Cask Use2024-06-18018 June 2024
Registration of Spent Fuel Cask Use
ML24163A0632024-06-12012 June 2024
2024 Licensed Operator Re-qualification Inspection Notification Letter Vogtle, Units 3 & 4
ML24155A1772024-06-0505 June 2024
Regulatory Audit in Support of Review of the LAR to Revise Emergency Diesel Generator Frequency and Voltage Ranges for Technical Specification 3.8.1, Surveillance Requirements
NL-24-0202, SNC Response to Regulatory Issue Summary 2024-01: Preparation and Scheduling of Operator Licensing Examinations2024-05-24024 May 2024
SNC Response to Regulatory Issue Summary 2024-01: Preparation and Scheduling of Operator Licensing Examinations
ML24141A0482024-05-17017 May 2024
EN 56958_1 Ametek Solidstate Controls, Inc
ML24094A1402024-05-16016 May 2024
Staff Response to Request for Revision to NRC Staff Assessment of Updated Seismic Hazard Information and Latest Understanding of Seismic Hazards at the Vogtle Plant Site Following the NRC Process for the Ongoing Assessment of Natural Hazard
ML24130A2412024-05-13013 May 2024
Integrated Inspection Report 05200025/2024001 and 05200026/2024001
ML24120A1812024-05-13013 May 2024
Request for Withholding Information from Public Disclosure Responses to NRC Request for Additional Information for Refueling Outage IR24 Steam Generator Tube Inspection Report – Enclosure 2
ML24101A2112024-05-11011 May 2024
Expedited Issuance of Amendment No. 198 Change to Technical Specification 5.5.13, Ventilation Filter Testing Program (VFTP)
NL-24-0191, Annual Radiological Environmental Operating Reports for 20232024-05-10010 May 2024
Annual Radiological Environmental Operating Reports for 2023
ML24127A2372024-05-0909 May 2024
Initial Test Program and Operational Programs Inspection Report 05200026/2024010
NL-24-0194, Revised Request for Relief and Alternative Requirements for Squib Valves First Test Interval (V34-IST-ALT-03-R1)2024-05-0707 May 2024
Revised Request for Relief and Alternative Requirements for Squib Valves First Test Interval (V34-IST-ALT-03-R1)
IR 05000424/20244032024-05-0101 May 2024
Cyber Security Inspection Report 05000424/2024403 and 05000425/2024403 Public
ML24120A2832024-04-30030 April 2024
Project Manager Reassignment
NL-24-0170, Responses to Second Round NRC Request for Additional Information for Refueling Outage 1 R24 Steam Generator Tube Inspection Report2024-04-25025 April 2024
Responses to Second Round NRC Request for Additional Information for Refueling Outage 1 R24 Steam Generator Tube Inspection Report
NL-24-0165, Annual Non-Radiological Environmental Operating Reports and Annual Radioactive Effluent Release Reports for 20232024-04-25025 April 2024
Annual Non-Radiological Environmental Operating Reports and Annual Radioactive Effluent Release Reports for 2023
IR 05000424/20240012024-04-23023 April 2024
–Integrated Inspection Report 05000424/2024001 and 05000425/2024001
NL-24-0154, Preservice Inspection Progam Owners Activity Report2024-04-16016 April 2024
Preservice Inspection Progam Owners Activity Report
2024-09-09
[Table view]
Category:Meeting Summary
MONTHYEARML24290A1582024-10-24024 October 2024
Summary of Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company Regarding a Proposed License Amendment Request to Change Table 3.3.8-1 for Vogtle Electric Generating Plant, Units 3 & 4
ML24292A0022024-10-22022 October 2024
Summary of October 16, 2024, Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request to Increase Flexibility in Mode Restraints
ML24213A2462024-08-0505 August 2024
Summary of Closed Meeting SNC Fleet - Physical Barriers Exemption
ML24187A0012024-07-17017 July 2024
Summary of Observation Pre-Application Public Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request to Revise TS 3.3.8, Engineered Safety Feature Actuation System for Vogtle Electric
ML24179A1592024-07-0202 July 2024
June 27, 2024, Summary of Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request for Vogtle Electric Generating Plant, Units 3 and 4
ML24156A1772024-06-11011 June 2024
Summary of June 6, 2024, Closed Meeting Held with Southern Nuclear Operating Company, Inc., Regarding the Physical Barrier Exemptions for Joseph M. Farley Nuclear Plant, Units 1 and 2, Edwin I. Hatch Nuclear Plant, Units 1 and 2, and Vogtle
ML24149A0742024-06-0101 June 2024
Summary of May 29, 2024, Closed Meeting Held with Southern Nuclear Operating Company, Inc., Regarding the Steam Generator Tube Inspection Report for Vogtle Electric Generating Plant, Unit 1
ML24122C6202024-05-0101 May 2024
Public Meeting Summary - 2023 Annual Assessment Meeting Vogtle Electric Generating Plant, Units 1, 2, 3, and 4 Docket Nos.. 50-424, 50-424, 52-025, and 52-026 Meeting Number 20240471
ML24108A0832024-04-19019 April 2024
Summary of Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request for Vogtle Electric Generating Plant, Units 3 and 4
ML24093A0612024-04-18018 April 2024
April 1, 2024, Summary of Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Proposed Alternative Requests to the Extend Examination Intervals for Joseph M. Farley Nuclear Plant and Vogtle
ML24068A0962024-03-18018 March 2024
Summary of 3-7-24, Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Co., Inc., Regarding a Proposed License Amendment Request for TSTF-577, Revision 1, Revised Frequencies for Steam Generator Tube Inspection
ML24025A1372024-01-31031 January 2024
Summary of Observation Pre-Submittal Meeting Held with Snc., Regarding a Proposed Alternative Request - Explosively Actuated Valves for Vogtle Electric Generating Plant, Units 3 and 4
ML24019A1932024-01-30030 January 2024
Summary of January 8, 2024, Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company Regarding a Proposed LAR for Vogtle Electric Generating Plant, Units 1, 2, 3, & 4; Hatch, Units 1 & 2; Farley, Units 1 & 2
ML23356A0282023-12-27027 December 2023
December 11, 2023, Pre-Application Meeting with SNC Regarding a Proposed Fleet LAR to Revise TS 5.3.1 to Relocate Training Qualification Requirements from TS to Their Qatr/Ndqam
ML23311A1302023-11-17017 November 2023
Summary of Nov. 6, 2023, - Closed Meeting Held with Southern Nuclear Operating Company, Inc., Regarding Physical Barriers Exemptions for Hatch Units 1 & 2, Farley Units 1 & 2 and Vogtle Units 1, 2, 3 & 4 (EPID L-2023-LLE-0018 & L-2023-LLE-0
ML23313A0952023-11-16016 November 2023
Summary of November 7, 2023, Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request for Vogtle Electric Generating Plant, Units 1 and 2
ML23303A2032023-11-0101 November 2023
October 24, 2023, Summary of Comment Gathering Public Meeting on Lessons Learned from the ITAAC Hearing Process for Vogtle Units 3 and 4
ML23275A0882023-10-12012 October 2023
Summary of Meeting with Southern Nuclear Operating Company
ML23272A1822023-10-11011 October 2023
Summary of September 28, 2023, Observation Pre Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request for Vogtle Electric Generating Plant, Units 3 and 4
ML23230A0212023-08-30030 August 2023
LAR-22-002 Technical Specification 3.8.3 Summary of 08-17-23 Public Meeting
ML23187A5742023-08-22022 August 2023
Summary of June 29, 2023, Meeting with Southern Nuclear Operating Company
ML23146A1542023-06-0505 June 2023
Summary of May 25, 2023, Meeting with Southern Nuclear Operating Company
ML23132A0412023-05-18018 May 2023
Summary of May 11, 2023, Meeting with Southern Nuclear Operating Company
ML23121A1692023-05-12012 May 2023
Summary of Meeting with Southern Nuclear Operating Company Vogtle LAR-23-006 U/3&4 More Restrictive Action for TS 3.1.9 Cvs Isolation Valves
ML23115A3282023-05-10010 May 2023
Summary of Public Meeting with Southern Nuclear Operating Company to Have a Pre-Submittal Discussion of Draft License Amendment Request (LAR) for Vogtle Electric Generating Plant (VEGP) Unit 3
ML23115A0662023-05-0101 May 2023
Summary of Public Meeting with Southern Nuclear Operating Company to Have Presubmittal Meeting for Vogtle Electric Generating Plant, Unit 4
IR 05000424/20040252023-04-28028 April 2023
Public Meeting Summary - Vogtle Electric Generating Plant, Units 1, 2, 3, & 4 Docket No. 5000424, 5000425, 5200025, 5200026, Meeting Number 20230375
ML23090A1422023-04-0303 April 2023
Summary of Conference Call Regarding the Spring 2022 Steam Generator Tube Inspections
ML23065A0732023-03-17017 March 2023
March 2, 2023, Summary of Meeting with Southern Nuclear Operating Company - Vogtle Electric Generating Plant, Unit 4
ML23055A0902023-03-14014 March 2023
February 16, 2023, Summary of Meeting with Southern Nuclear Operating Company
ML23048A0682023-03-0101 March 2023
Summary of February 13, 2023, Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc. Regarding a Proposed License Amendment Request for Vogtle Electric Generating Plant, Units 1 and 2
ML23037A0032023-02-0606 February 2023
Summary of February 2, 2023, Public Meeting with Southern Nuclear Operating Company
ML23012A0512023-01-17017 January 2023
January 11, 2023, Summary of Public Meeting with Southern Nuclear Operating Company (SNC) Regarding Vogtle Emergency Technical Specification Amendment
ML22349A2142023-01-0303 January 2023
Summary of December 8, 2022, Public Meeting with Southern Nuclear Operating Company
ML22336A0812022-12-0505 December 2022
Summary of December 1, 2022, Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request for Vogtle Electric Generating Plant, Units 1 and 2
ML22335A4922022-12-0202 December 2022
Summary of Observation Pre-Submittal Meeting Held with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Request for Vogtle Electric Generating Plant, Units 1 and 2
ML22319A0132022-11-30030 November 2022
Summary of a Public Meeting with Southern Nuclear Operating Company on November 10, 2022
ML22322A1672022-11-28028 November 2022
Summary of 11/15/2022 Public Meeting on Lessons Learned
ML22271A0182022-10-0404 October 2022
Summary of Public Meeting with SNC on Lessons Learned Final
ML22257A2362022-09-19019 September 2022
Summary of September 13, 2022, Partially Open and Partially Closed Pre-Submittal Meeting Held with SNC, Regarding a Proposed OLM License Amendment Request for Vogtle Electric Generating Plant, Units 1 and 2
ML22243A0302022-09-0909 September 2022
Summary of a Public Meeting with Southern Nuclear Operating Company on August 25, 2022
ML22145A6052022-06-0202 June 2022
Summary of May 24, 2022, Public Meeting with SNC, Regarding a Proposed Alternative Request for Performance-Based Leakage Test Frequencies for the Refueling Water Tank Suction Check Valves for Vogtle, Units 1 & 2
ML22145A4492022-05-27027 May 2022
Summary of May 23, 2022, Public Meeting with SNC, Regarding a Proposed License Amendment Request to Change Technical Specification 3.8.1 and Implement TSTF-163 for Vogtle Electric Generating Plant, Units 1 and 2
ML22131A3422022-05-18018 May 2022
Summary of Public Meeting with Southern Nuclear Operating Company, Inc., Regarding a Proposed License Amendment Requests to Implement Alternate Source Term, TSTF-51, TSTF-471, and TSTF-490 for Vogtle, Units 1 & 2 (EPID No. L-2022-LRM-0033
ML22132A0102022-05-17017 May 2022
Meeting of Public Meeting with Southern Nuclear Operating Company, Inc., Regarding Proposed Accident Tolerant Fuel License Amendment Request and Exceptions for Vogtle Electric Generating Plant, Units 1 and 2
ML22123A0652022-05-0202 May 2022
Public Meeting Summary Vogtle Electric Generating Plant, Units 1, 2, 3, & 4 Docket No. 50-424, 50-425, 52-025, 52-026, Meeting Number 20220330
ML22098A1292022-04-26026 April 2022
Summary of March 31, 2022 Public Meeting with Southern Nuclear Operating Company
ML22095A2292022-04-11011 April 2022
Summary of Conference Call Regarding the Spring 2022 Steam Generator Tube Inspections
ML22077A5432022-04-0404 April 2022
Summary of Meeting with Southern Nuclear Operating Co
ML22028A0462022-02-0101 February 2022
MTS - Meeting Summary - Pre-Submittal Meeting on January 27, 2022 - Vogtle ATF LAR and Exemption
2024-08-05
[Table view] |
Text
December 19, 2006 Mr. D. E. Grissette Vice President Southern Nuclear Operating Company, Inc.
P.O. Box 1295 Birmingham, AL 35201-1295
SUBJECT:
VOGTLE ELECTRIC GENERATING PLANT, UNIT 1 (VOGTLE) -
SUMMARY
OF CONFERENCE CALL REGARDING THE 2006 FALL OUTAGE STEAM GENERATOR TUBE INSPECTIONS (TAC NO. MD3371)
Dear Mr. Grissette:
On October 18, 2006, the Nuclear Regulatory Commission (NRC) staff participated in a conference call with Southern Nuclear Operating Company, Inc., representatives regarding steam generator inspection findings during the fall 2006 refueling outage. The NRC staff is forwarding the enclosed summary for your information.
Sincerely,
/RA/
Robert Martin, Senior Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-424
Enclosure:
October 18 Conference Call Summary cc w/encl: See next page
ML063390165 NRR-106 OFFICE NRR/LPL2-1/PM NRR/LPL2-1/LA NRR/LPL2-1/BC NAME RMartin MOBrien EMarinos DATE 12 /11 /06 12 /18 /06 12 / 19 /06 OCTOBER 18, 2006, CONFERENCE CALL
SUMMARY
STEAM GENERATOR TUBE INSPECTIONS VOGTLE ELECTRIC GENERATING PLANT, UNIT 1 DOCKET NO. 50-424 On October 18, 2006, the Nuclear Regulatory Commission (NRC) staff participated in a conference call with Southern Nuclear Operating Company, Inc., representatives, to discuss steam generator (SG) inspection activities at Vogtle Electric Generating Plant, Units 1 and 2, (Vogtle Unit 1 and Vogtle Unit 2), particularly those activities during the Vogtle Unit 1 fall refueling outage (designated 1R13). A summary of the information discussed during the call along with some background information is provided below.
Vogtle Unit 1 has four model F SGs designed and fabricated by Westinghouse. Each SG contains 5626 thermally treated Alloy 600 tubes with an outside diameter of 0.688 of an inch and a nominal wall thickness of 0.040 of an inch. The tubes are hydraulically expanded for the full depth of the tubesheet at each end and are supported by a number of stainless steel tube supports. In the U-bend region, the tubes are supported by anti-vibration bars. The tubes are arranged in a square pitch.
Vogtle Unit 1 SGs began commercial operation in 1987. In 2002, there was an inadvertent addition of phosphate to the Unit 1 and Unit 2 SGs. In the spring of 2004, Vogtle Unit 2 pulled two tubes to investigate crack-like indications at the expansion transition. A laboratory non-destructive examination of both of these tubes indicated that there was no cracking at the expansion transition. Destructive examination of one of these tubes confirmed there was no cracking at the expansion transition. In the spring of 2005, Vogtle Unit 1 identified cracking in bulges within the tubesheet. No crack-like indications were found during the fall 2005 inspection in Vogtle Unit 2. During the recently completed fall 2006 SG tube inspections at Vogtle Unit 1, crack-like indications were identified at the expansion transition. These findings are discussed below. The next Vogtle Unit 2 SG tube inspections are scheduled for the spring of 2007.
During the 1R13 outage, 100 percent of the tubes in SGs 2 and 3 were inspected with a bobbin coil. In addition, the U-bend region of 50 percent of the row 1 and 2 tubes, and 100 percent of the dings and dents greater than 5 volts in the hot leg in SGs 2 and 3 were inspected with a rotating probe. The SGs were chemically cleaned before the tube inspections and the SGs operate at a hot leg temperature of 618 o F.
During 1R13, +Point' inspections of the top of the tubesheet region were planned for 50 percent of the tubes in SGs 2 and 3. During this initial sample, indications of outside diameter stress corrosion cracking were found in several tubes at the bottom of the expansion transition region in both SGs. As a result of finding these indications, the scope of inspection at the top of the tubesheet was expanded to include 100% of the tubes in SGs 2 and 3 and 25 percent of the tubes in SGs 1 and 4. The extent of this inspection was from 3 inches above to 3 inches Enclosure
below the top of the tubesheet. As a result of finding indications in the initial sample inspection in SGs 1 and 4, the scope of the inspection at the top of the tubesheet was expanded to include 100 percent of the tubes. At the time of the conference call, 10 indications had been identified:
3 in SG 1, 2 in SG 2, 3 in SG 3, and 2 in SG 4. The licensee indicated that evaluations for other possible indications, some in the sludge pile region, were still ongoing in SG 4.
For SGs 1, 2 and 3, the indications are predominantly located in low row, high column tubes along the periphery (between rows 1 through 6 and between columns 103 through 119).
In order to confirm the indications, five different inspection methods were used: +Point',
Ghent, 3 Coil Delta, and the 0.080 and 0.115 pancake coil. All of the inspection methods confirmed the indications with the exception that some of the small amplitude signals were not identified with the 0.080 pancake coil. Given these results, the licensee concluded that these indications are cracks.
The largest crack-like indication was measured to have a circumferential extent of 180 degrees.
The maximum reported depth was 67 percent throughwall. The indication with the largest circumferential extent was not the same indication that had the maximum depth. The voltages associated with the indications were approximately 0.2 volts, although there were two indications that had voltages of 0.60 volts and 0.73 volts. A historical review of the +Point' data for the tubes in which the ODSCC indications were detected this outage was performed.
This review did not identify any precursor signals in these tubes.
The licensee stated that it had alerted the industry (other licensees of pressurized-water reactors) regarding this issue.
All tubes with crack-like indications will be plugged and stabilized. The licensee considered pulling a tube or tubes, but due to a major tube-pull project overseas, the licensee was not able to pull a tube given its outage schedule. The licensee will evaluate pulling a tube during the next refueling outage. Due to the location of the tubes with crack-like indications in relation to the divider plate, it is not clear whether pulling a tube is feasible. With respect to similar operating experience, the licensee indicated that Comanche Peak Unit 1 had first detected outside diameter circumferential cracks in a similar region of the tube bundle.
The licensee also stated there were indications near the top of the tubesheet that were identified with the +Point' probe but not confirmed with the Ghent, 3 Coil Delta probe or the 0.080 coil. These indications had voltages of approximately 0.06 volts to 0.08 volts.
In addition to crack-like indications found during the inspection, a volumetric flaw above the cold leg flow distribution baffle measuring 42 percent through-wall was detected in one tube.
The indication was attributed to a loose part. +Point' inspections were performed at this elevation for a 2-tube buffer surrounding this volumetric flaw. No possible loose parts were identified during this inspection. Given the location of the indication, visual inspections could not be performed. Other volumetric indications were observed in SG 2, however, they measured less than 10-percent through-wall.
Inspections were performed on a sample of bulges and overexpansion in the tubesheet region (i.e., from the top of the tubesheet to 17 inches below the top of the secondary face of the tubesheet). No indications were found during these inspections.
Based on the information provided, the NRC staff did not identify any technical issues that warranted follow-up action at this time.
Vogtle Electric Generating Plant, Units 1 & 2 cc:
Mr. Laurence Bergen Mr. D. E. Grissette, Vice President Oglethorpe Power Corporation Southern Nuclear Operating Company, Inc. 2100 East Exchange Place P.O. Box 1295 P.O. Box 1349 Birmingham, AL 35201-1295 Tucker, GA 30085-1349 Mr. N. J. Stringfellow Arthur H. Domby, Esquire Manager, Licensing Troutman Sanders Southern Nuclear Operating Company, Inc. Nations Bank Plaza P.O. Box 1295 600 Peachtree Street, NE Birmingham, AL 35201-1295 Suite 5200 Atlanta, GA 30308-2216 Mr. T. E. Tynan, General Manager Vogtle Electric Generating Plant Resident Inspector Southern Nuclear Operating Company, Inc. Vogtle Plant 7821 River Road 8805 River Road Waynesboro, GA 30830 Waynesboro, GA 30830 Mr. Jeffrey T. Gasser Office of the County Commissioner Executive Vice President Burke County Commission Southern Nuclear Operating Company, Inc. Waynesboro, GA 30830 P.O. Box 1295 Birmingham, AL 35201-1295 Mr. Steven M. Jackson Senior Engineer - Power Supply Municipal Electric Authority of Georgia 1470 Riveredge Parkway, NW Atlanta, GA 30328-4684 Mr. Reece McAlister Executive Secretary Georgia Public Service Commission 244 Washington St., SW Atlanta, GA 30334 Mr. Harold Reheis, Director Department of Natural Resources 205 Butler Street, SE, Suite 1252 Atlanta, GA 30334 Attorney General Law Department 132 Judicial Building Atlanta, GA 30334
