ML031110256
ML031110256 | |
Person / Time | |
---|---|
Site: | Davis Besse ![]() |
Issue date: | 07/25/2002 |
From: | Office of Nuclear Regulatory Research |
To: | |
References | |
FOIA/PA-2003-0018 | |
Download: ML031110256 (14) | |
Text
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
-NROPreecisional Art Howell Ron Lloyd Joe Donoghue Bob Haag Tom Koshy Pat Castleman Russ Bywater Joelle Starefos Sonia Eischen (State of Ohio; Observer)
David Timm (Office of Inspector General)
Using modified IAEA approach. Fact Level. What Level. Conclusion Level.
a NRC failed to adequately assess svmptomsof RCS leakage.
12 A CAC/Rad Monitor cleaning known by NRC through BC level 13 A BA on head known by SRI during RFO12 16 A RIII (Grant) knowledge of Rad Monitor 18 A BCs logs on CAC/RMs & discussed in morning meetings 19 A CAC cleaning observed by inspectors (DRS) 20 A PM knew about CACs 22 A DRP BC listed CAC cleaning (2001) 23 A RIII didn't see CAC/RM cleaning as important 38 A No one suggested NRC look at RCS leakage in containment during PIR 41 A 3 inspection reports discussing RMs without conclusions 52 A RIII didn't view leakage as a problem 58 A Multiple cleaning of CACs 76 A No documentation of CAC evaluation inspection 77 A No NRC doc of RM leak detection reliability insp.
1 of 14 IU
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NC PreDCciioa-83 A No open items for CAC/RM or BA on head 87 A Pzr safety valve mod increased leakage; NRC accepted without question 88 A Assumed Pzr safety valve leakage was reason for CAC fouling 97 A CR for CACJRM not seen as safety-sig would be screened out 98 A NRC Briefing package for Merrified didn't include BA problems 107 A TS requirements for CACIRM were relaxed 118 A BC didn't tell RI to pursue BA issues 125 A RA knew of CAC issues b NRC failed to follow-up on Generic Communications.
59 B 62001 not used for DB (precursor events) 61 B 62001 used 15 reactors (all RIV PWRs) 62 B No insp followup of GL97-01 66 B NRC followup for 88-05 audited 10 plants; DB acceptable 129 B TI on BU2001-01 didn't address BA issues 132 B 2515 IP do not look at BA/GC followup 133 B The old inspection program (9000 series) looked at OE issues 154 B # of Generic Comm (NRC) not corrected with # of events 156 B MD8.5 can't be followed because it hasn't been updated 160 B No NRC programmatic guidance for effectiveness review of generic comm.
161 B Sample/shotgun method for verification of generic comm implementation 164 B IP62001 deleted w/o considering why it existed 165 B NRC generated 17 boric acid generic communication 187 B 11/93 SER recommended inspection (visual) or leak detection system 189 B 11/93 SER recognized circumferential cracking, but didn't make recommendations 2of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002) vNRC PieDe7isiona 1 190 B Staff action plan GL97-01 can't be found 201 B GL97-01 closeout for DB based on generic info 202 B DB was the only B&W licensee that didn't do inspections (ref GL97-01) NRC 232 B 1972 requested enhanced ISI for BA corrosion c NRC failed to understand implications of BA corrosion.
14 C Licensee stated that NRR knew about BA on head 15 C SRI saw CR on BA on head 28 C BA CRs not selected for PIR 29 C Abbreviated version (issue) of BA CRs not represented 33 C No apparent NRC followup of 96, 98 PCAQs 42 C Aware of BA on RPV head and didn't inspect 43 C SRI knew of flange leaks 45 C Neither of Residents received training on BA 49 C DRP BC and former SRI (only) knew of flange leaks 50 C Flange leaks not pursued 65 C 1992 precursor insp no perf issues/no F/U of BA control prog 95 C RIII saw RC-2 as a material control problem -vs- boric acid prog prob 105 C NRC doesn't review owner's group input 116 C BC/SRI/RI didn't observe RPV head videos 128 C RI reviewed CR/equivalent in some manner 130a C BA buildup not a safety issue by NRC 155 C NUREG 6245 (CRDM crack) NRC not aware of B&W content 169 C NRC 1993 SER addressed RVH nozzle cracks as not immed. safety issue 197a C Risk significance of BA on RPV head is low NRC 3 of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NRC PreDecisional' 222 C NRC staff believed dry boric acid not corrosive 226 C Postulated breech of RPV not considered 227 C Industry and NRC were managing BA issue by leakage 228 C NRC doesn't review all of the industry guidance on BA 229 C NUMARC 1993 and NEI 1995 letters - GL88-05 will let the industry locate leaks before a real problem is identified 233 C 1993 2.206 Greenpeace response - cracking issues d NRC failed to establish adequate requirements.
139 D Enforcement history doesn't equate with OE 140 D Lack of enforcement for RCS leakage 141 D Enforcement/NRR trying to figure out what should be done for RCS leakage 142 D 1997 SONGS nozzle cracking cited Maintenance Rule 143 D NRC response (policy) not consistent - SONGS/Oconee 145 D No ASME Code requirement (of inspections/RCS leakage) 146 D Code didn't require insulation to be removed for inspections 147 D VC Summer had RCS leakage and didn't report it 149 D Several "no color" issues design -vs- performance 205 D 12/31/2001 was an arbitrary date for shutdown; basis question 219 D Code did not require insulation removal (VT-2) 243 D Enhanced visual meant for circ, not axial cracking (vol NDE) 245 D ANO a through wall CRDM crack is a statistical certainty 253 D Several CRDM nozzles cracked, some through wall NRC e NRC g r mete rogras failed to adeguatelv assess DB performance 1 E Region viewed Davis-Besse as good performer.
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Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
AVRU e-Decisionatl 8 E PM inspection approach changing.
21 E One PPR summary listed CAC cleaning 25 E PI&R/40500 did not review area 26 E PI&R samples began 1999 for 3/01 (gap issue) 27 E Gap of 2 /2 years between CA inspections (missed events) 39 E Inspection reports don't list all docs reviewed (6 years of reports) 44 E RC-2 escalated enforcement didn't require closeout inspection 46 E Inspection on RM didn't provide any performance issues 47 E Neither the old/new insp programs found/discussed RM issues 51 E Former SRI did not perform any followup on leak hunt plan RFO12 55 E NRC prompted Lic regarding RCS leak on MUIA described as positive in IR 56 E DB PIR viewed as the best by RIII 60 E 62001 cancelled in 10/01 67 E NRC audit of BAC didn't include Rx head/instr 71 E Not enough hours in ROP for (BA) inspections didn't allow some inspection 72 E Verbatim comp. W/insp procedures (not there/can't do) 73 E Can't go outside of the baseline unless you have a >green finding 74 E Baseline inspection doesn't include structures or passive components 75 E ROP eliminated good practice of containment closeout insp 82 E ISI didn't look at A600 85 E RIII issued SL3 for RC-2; would be a green finding today 86 E RC-2 event would have not gone beyond baseline 96 E RIII had differing -views for RC-2 followup 100 E Some interviews indicated RIISRI not as visible in ctmt and CR post ROP 5of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
XRl C-Pre-Decisional 106 E MC2515 AppD doesn't provide thorough guidance for review of CR 115 E NRR PM limited visits to DB 121 E NRC thought that the licensee was rigorous in their leak hunt 122 E RI thought the RPV head was 100% cleaned 127 E ALARA insp didn't show that CAC cleaning was largest dose 204 E No process for verifying licensee info for continued operation 206 E PM don't conduct site visits 207 E Some PM haven't visited plants 208 E PM didn't review commitment change reports 211 E NRR not implementing procedures 212 E LA/SE for RM for RCS leakage didn't consider DB OE 213 E NRR perception was that DB was a good performer 224 E Risk informed process didn't alert the NRC to a potential risk 225 E Over-reliance on risk information -vs- deterministic 252 E 62001 intended for 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> every other outage 270 E Kerosene burner not eval'd for ctmt 271 E No oper eval for the clogging of CACs 272 E Non-conservative assumption of LOCA steam clean CACs 278 E Lic didn't complete all RC2 CAs 290 E No doc'd eval of CAC clogging 293 E All PI's green prior to event 294 E Inadequate temp mod safety eval on code safety seat leakage f NRC staff resources & experience 2 F NRC staffing level not filled for all positions 6of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NAEPreDecisional 3 F One year period (1999), only one Resident on site.
4 F Project Engineer - two 8-month gaps.
5 F Resident inspectors not certified.
6 F SRI position delayed in filling.
7 F High Project Manager turnover rate (9 PMs in 10-years) 9 F Limited commercial nuclear experience RI 10 F Resident inspector had a materials background 11 F SRI experience with only DB containment 40 F Low number of inspection hours compared to other RIII sites (1/2 in 1999) 53 F 1998 events diverted inspection efforts re:BA issues 57 F Resident not aware of OOS logs 63 F PE little time at DB (1997&1999) 92 F Between PE coverage gaps, 8 months/3months coverage/8 months 93 F BC had Clinton 0350 plant coincident w/DB 110 F RIII resources decreasing 111 F RIII insp contractor support poor 112 F Rill too many competing priorities which detract from insp.
131 F No 1245 cert requirements for BA corrossion 158 F Contract support after '98 report dried up (staff decreased/# reports decreased) 167 F AEOD had 80+ FTE; now 2.5 FTE for OE (RES) 215 F No guidance for background training for PM g ~ NRC failed to communicate critical information 17 G Other than DD-DRP; others didn't recollect CAC/RM issues 94 G NRR inspection branch has no feedback form on Plant status time as addressed by RI interview 7of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NRCPriDezsioratlU 101 G Procedure for RIII morning meeting isn't followed 102 G RIII not conducive to info exchange 103 G Senior RIII Managers not the audience for the morning meeting 117 G RI not aware of FeO on CAC 126 G RA didn't know about BA on head 136 G IRO didn't participate to follow MD8.3 for AIT determination 137 G NRR/RIII didn't follow MD8.3 203 G Deferral of DB shutdown not well documented 216 G Interviews indicate that NRR and RIII communications poor/nonexistent 291 G Late arrival of calcs for crack propagation h NRC failed to adequately assess relevant operating experience 157 H OE review in NRC not performed by independent or long review 163 H NRR is reactive for short-term/current event 166 H NRC generic issue program takes too long/too hard ...use bulletins instead 170 H Foreign OE was reviewed by NRC 171 H 70 LERs about Boric Acid leaks 172 H Axial cracks known from early 1970s , Circumferential from 1980s 173 H LIC-503 references some wrong procedures in RES 183 H No clear process for using foreign experience 184 H French corrective actions were documented but never used 185 H Mind set that French CA was an over reaction from NRC perspective; aggressive inspection was reponse 186 H NRC never asked the French why they were replacing their RPV heads 188 H Swedish, Spanish, Japanese, French have replaced heads 193 H NRR staff not aware BA leakage OE 8of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
XlC-PreDeeisionab 209 H RES procedure 2i not used/not known by staff 210 H Cracking/BA corrosion not considered by either NRR or RES to be a GI (MD 6.4) 230 H GI program relies on user needs before taking action 231 H Preferred process flow for OE: nothing; IN; BU; GL; GI (all else fails) 297 H No NRC review of submittals/reports (ISI) i Licensee failed to implement Fo p guidance.
202a I DB was the only B&W licensee that didn't do inspections (ref GL97-01) LIC 236 I No BWOG verification for implementation of GL97-01 237 I No BWOG verification for implementation of GL88-05 247 I No tracking system to ensure that industry guidance was included in site guidance/
processes.
261 I 93 B&W report flange leaks need to be eval first 289 I BA corr handbook shows CAC/RM as evidence of RCS leak i Licensee failed to understand implications of BA corrosion.
32 J BA on head was a "routine" CR 36 J 1996 CR on BA stayed open for -2 years 130 J BA buildup not a safety issue by DB 155a J NUREG 6245 (CRDM crack) Industry not aware of B&W content 178 J BACC person also had many other duties as a system engineer 194 J BWOG rep didn't know the significance of Brown/red tinted BA buildup 197 J Risk significance of BA on RPV head is low LIC 217 J BA procedure not "QA" until 5/02 234 J Mod on service structure delays 239 J Ombudsman & cleaning statements 274 J PRG staff didn't viewed head tapes 9of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NRCPre-Decisional\
275 J Former VP viewed as-found, not after tape until Fall2001 282 J Only staff involved in head cleaning 296 J PCAQ 96-0551 was one of ten oldest CRs before it was resolved 298 J Multiple people involved in head cleaning w/o raising issues 299 J Same job done by Framatome at other plants?
k Licensee failed to resolve chronic RCS leakage.
24 K Routine CAC cleaning 108 K CAC/RM fouling may have been the impetus for TS change in #107 109 K HEPA filter for RM may defeat the purpose of the RM workarounds -vs- fix the problem 119 K Licensee not rigorous in finding RCS leaks 120 K Licensee deleted Mode 3 walkdown for BA 235 K CAC fouling and ALARA 244 K DB entered a 6-hour shutdown TS situation because of RM Problems with BA 248 K Ability to differentiate between flange leakage/ head penetration leakage 255 K Until RFO13 lic had flange leaks 262 K Heavy boron buildup on CACs 268 K No systematic leak search for 12RFO 269 K Deleted mode 3 walkdown 273 K Long history of thermowell leaks 280 K Triage plan for flange leak / didn't fix all flange leaks 287 K 100% NDE 5.7Rem estimate <past head cleaning 300 K Relief valve mod masking other leaks in 1998-99 time frame i Licensee failed to properlv implement an adequate BACC program.
34 L 1996 CR explicit on the BA concern 10of 14
I Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NRC PreDedisiwal, 35 L -50% of RPV head cleaned in 1996 70 L BAC checklists not kept/tracked/trended 123 L None of the RPV head cleanings were 100%
124 L Lost control of video tapes 144 L BAC procedure wasn't followed 251 L Appropriate cleaning methods for RPV head (water-vs-vacuum) 254 L #4, 5 nozzles still had boron on them following cleaning 260 L Couldn't complete head cleaning due to schedule pressure 263 L Potential CRDM G9 leak was crack, not dispositioned 266 L RCS sys engr: scaffold was removed without permission 267 L RP considered head cleaning as decon, so no procedure 279 L No deviations from RF012 WO to clean RPV head 281 L RCS sys engineer upset that they head wouldn't be totally cleaned 283 L Index of head tapes incomplete 284 L 4/17/00 head mislabeled as as-left 285 L Head inspection tape not documented as to what was actually inspected - QA zip m Licensee failed to learned from internaVexternal OE.
68 M DB's BACC didn't include Rx head/instr until 5/02 151 M Oconee OE not evaluated at DB until 5/2002 152 M OE in US ...Boric acid leaks. #1 area was CRDM, DB considered not significant 153 M 100% B&W units had RCS PB leakage 162 M DB OE procedure doesn't require NRC LER review 168 M 100% CE had RCS pressure boundary leakage 174 M 45% of Oconee cracking (CRDM) appears in the same quadrant as DB leakage problems 11 of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NRCT'feDeeisional1 175 M CE plants dominated RCS instrumentation nozzle leakage (10 of 13 leaks) 176 M Average # of operating years prior to CRDM leakage -22 years 179 M Foreign experience would indicate that the "crack" model is flawed 191 M NUREG/CR 6245 recommended enhanced online leakage detection systems (NRC?)
192 M Calvert Cliffs LER indicated wet boron vs dry 198 M Annealing nozzle temps were different than required 200 M 3 LERS involved pzr material wastage 218 M B&W recommended the service structure mod 276 M Two precursor BA events ...RC2, SG line n Licensee staff resources & experience 159 N 40-50% DB staff decrease over 10 years 246 N Multiple job assignments depending on cycle (outage, ops, EP) 277 N Lack of system engineer continuity o Licensee failed to communicate critical information 150 0 Lic Response to BU2001-01 contained many inaccurate info /response 177 0 Many licensee (DB) staff thought that a whole head inspection/cleaning was done 264 0 Lic Managers I staff knew of head cleaning %, lower staff thought that head was 100% cleaned 265 0 Lic managers said they showed NRC the as-found video tapes of the head w Awaiting additional review 31 W We rely on lic to give NRC correct info 37 W Long time to close out CRs 54 W CCW event (10/98) resulted in Spec Insp 64 W Limited entries into containment by NRC 78 W 1997 NOPINOT walkdown by NRC found no leaks 12of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NRC PreDecisional 81 W 1992 uptake event insp closeout, then 1998 uptake occurred 84 W RIII factored BU2001-01 commitments as part of Baseline prog.
89 W RIII invoked MC0350 w/o DB having met criteria 90 W DB event risk not completed yet 91 W SDP has taken 5 months 113 W Only 1 SES manager inside containment since 1996 114 W Limited senior manager visits to DB 134 W No NRC review of Ombudsman files 138 W Range of opinions on whether an AIT/IIT/SI 180 W Story differences between what DB told NRC -vs- what NRC thought they were told about BA by DB 181 W NRR not told about red/brown BA buildup until after the DB event 182 W After the RPV head videos were shown to the NRC, a vote was taken: 3 for shutdown; remaining (10-13) voted to allow continued operation 196 W Conclusion in the EPRI guidebook not supported 199 W "Boric acid on the head is good."
214 W INPO ratings declined from 1 to 2 within the last few years 220 W DB experienced no insulation deflections caused by BA buildup on the head 221 W License Renewal report (GALL) addresses acceptability of GL88-05 for aging management to be updated to reflect lessons learned 223 W Extending the inspection for DB was largely based on the belief that a "strong" VT-2 inspection was done at DB 238 W O&M/capital budget and actuals have decreased over last 10-years 240 W BU2001-01 documentation responses by DB not accurate 241 W 12-16 people at DB reviewed DB response to BU2001-01 242a W MNSA - repair of joints, boric acid issues NRC 13 of 14
Davis-Besse Lessons Learned Task Force Meeting (7/24-25/2002)
NRCPreDecisiohrcah 242 W MNSA - repair ofjoints, boric acid issues LIC 249 W Bonus correlation with operations 256 W VP - No NDE tools by 12/31 257 W VP -Ops last know 259 W Lic did not eval use of power washer 292 W QA group didn't have a problem with BAC RFO12 report shows positive finding 295 W NRC questioned how the licensee was able to do a visual insp. given that boron was left on the head x Deleted 30 X CRs reviewed for PI&R -7000 48 X SSDI insp in 2000 indicated performance was worse than expected 69 X 40500 insp in '98 indicated that commitment tracking NG 79 X SRI 97-98 no recollection of flange leaks 80 X Former SRI works for FENOC 99 X PI&R doesn't allow independent look by inspectors 104 X PI&R team leader thought that the short form description of CR was adequate 135 X RIII inspector was told that DB was SALP 1 didn't take findings seriously (arrogant) 148 X Nothing in allegation area was relevant to BA/cracking issues 195 X BACC person indicated that the next major nuclear accident will be caused by BAC 250 X Basis for dose estimates for RPV head inspections 258 X Eng received closed door talking to for CR initiation 286 X Lic is doing an assessment of BU2001-01 submittal 288 X No VT-2 insp during RFO12 per RCS sys eng 14of 14