ML091980135

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License Renewal Commitments Inspection, Exit Meeting, Dec. 3, 2008
ML091980135
Person / Time
Site: Oyster Creek
Issue date: 12/03/2008
From:
NRC Region 1
To:
References
FOIA/PA-2009-0070
Download: ML091980135 (5)
v • d • e


Text

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  • WII HHEL FOR Xi, Oyster Creek HHEL O .

License Renewal Commitments Inspection Exit Meeting - DeGG3,2008

Introductions

" NRC Region 1

" NRC HQ

" NRC Residents

" AmerGen

" NJ DEP (Observers)

Excellent Overall Cooperation from everybody

>>> use of the Certrec Internet Database was quite helpful Special Thanks 9 Pete Tamburro (LR Program Owner)

  • Chris Hawkins (NDE Level-Ill)
  • Cal Taylor &Jhansi Kandasamy Tough Inspection Schedule & Difficult Inspection
  • LR outage schedule slipped due to unexpected issues

" Some NDE UTs re-scheduled, due to unanticipated physical interference issues

  • Bay 11 Coating Blisters
  • Cavity Leakage and Water Intrusion into 4 bays

" As a result, our inspection ran into a 2nd on-site week and a 3rd in-office week Documentation Team Report 45 days after the Exit Meeting (mid Jan)

Exec Summary of Inspection Results

.Satisfactory Actions to evaluate primary containment structural integ. y.n 4 (b)(5)

These items were also commitments to Ueneric Letter tst-ut

" Strippable Coating to Prevent Water Intrusion

  • Monitoring of Sand Bed Drain Lines
  • For the selected samples,-[ (b)(5) - *..A K

" Sampled 9 AMPs t6T"erify Commitment Implementation

" No Problems or Issues Identified, with Two/Three (??) Notable Exceptions-(b)(5) ](two items) .

  • Perform Full Scope inspections of sand bed region every other outage
  • Monitor drywell trenches for water every refueling outage, until trenches are restored
  • Verified 2 commitment changes were done iaw Exelon commitment management program
  • Bolting Integrity Program (commitment 12)
  • Rx Vessel Axial Weld Examination Relief Request (commitment 48)
  • Regarding §54.21gb) Annual Updates, you intend to submit your 2008 Amendment Update by the end of the year -f (b)(5) -1 Infornatlon inthis record was deated W accordance with the Fr .om of Infoiind lA&

Ex-impfn*n__r_ n--OIrc iaOy FOIPA -deisionaa -H=ti~n_ -Ofcial e1o 1y Page 1 of 5

P e-Decision ,Inform on Off Kial Upe,1I<

Inspection Details--7 (b)(5)

U (1) Commitment 27, ASME Section Xl, Subsection IWE, Item (2ý7 (b)(5)

A strippable coating will be applied to the reactor cavity liner to prevent water intruston into ine gap between the drywell shield wall and the drywell shell during periods when the reactor cavity is flooded.

  • The strippable coating initially limited leakage into the cavity drain trough at < 1 gpm. On Nov 7, the leakage rate took a step change to 4 to 6 gpm. Water was subsequently identified in 4 sand bed bays.

(2) Commitment 27, ASME Section XI, Subsection IWE, Item (3Y Sand bed region drains will be monitored daily during refueling outages.

(b)(5) 3

  • Sand bed drains were remotely monitored by checking poly bottles, attached via tygon tubing to funnels hanging below the drain lines. The drain lines were not directly observed.

(b)(5)

(b)(5)

ANY QUESTIONS at this point P,4-decisi/nal ,nform/tion -- Off~ial U Only/ Page 2 of 5

P/ Decls4*

. _7nforaton -- Offi4*I U*e-Op//

(b)(5)

(3) Commitment 27, ASME Section Xl, Subsection IWE, Item (3)- (b)(5)

Reactor cavity seal leakage trough drains and the drywell sand bed region d-iins will be monitored for 7'.

leakage. Periodically.

  • Drain line was found isolated during a boroscope examination to verify no line blockage.

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P(e-decis~(nallInfor to-n Of~lciaI e94(IYPae3 Page 3 of 5

PreS~eision 7 ~r in -- Offldai UJE~J Inspection Observations that will go into the report ASME iWE, Containment In-service Inspection

  • DIW UT Examinations

" We reviewed over 2000 separate UT readings [41 7x7 arrays & 7 1x7 arrays]

  • We reviewed all sand bed region UT readings [111 UTs]
  • No on-going corrosion or trend was identified
  • No statistically significant deviations from 2006 data values

" Leakage Monitoring of cavity drain and sand bed drains

" Problems with the Method of monitoring -- as already discussed

  • Good Actual monitoring practices and log keeping [people in the plant]
  • Good pro-active monitoring actions during cavity flood-up (continuous Ops monitoring)

" Good compensatory actions, when strippable coating de-laminated

  • You are re-thinking action levels, based on cavity drain leakage rates

" Calc and Action plan established 12 gpm Admin Limit

  • Didn't expect water intrusion at observed leakage values
  • Numerous deficiencies identified in 7 of 10 bays (none in 2006). All problems were repaired.

" Moisture barrier function not impaired, no cracks or separation fully penetrated the seal

  • Surface cracks

" Separation from shell or floor

  • Inadequate epoxy cure -- initial installation issue, from 1992 Protective Coating Monitoring and Maintenance Program
  • D/W Exterior Service Level II Coating, in Sand Bed Bays
  • Bay 11, one small 1/4 inch broken blister identified, with a 6" rust stain
  • During initial investigation, 3 smaller unbroken blisters also found

" All 4 blisters were within a 1-2 inches square area, and all were thoroughly evaluated and fixed.

  • Good extent of condition, 4 bays re-inspected by a different level-Il
  • During follow-up, you identified a 2006 video that showed the same 6" rust stain

" Estimated corrosion of - 3 mils, over a 16 year period

" No impact to D/W structural integrity, when compared to existing thickness margins Prý-decisic*al Informat -. OfficUal U/e Page 4of 5

iDecisi Infor 9 6/$n-Offle, ( e0 y Observations that DON'T go into the report ASME IWE, Containment In-service Inspection

  • Leakage Monitoring of cavity drain line

?? Drain line found isolated during a boroscope examination (to verify no line blockage)

  • Newly installed in 2006. Turned out to be an interference item to D/W UTs.
  • Done as part of Structural Monitoring Program. No issues or problems identified.
  • Commitment for post-PEO is per ASME Sec-XI IWE.
  • We asked whether your Structural Monitoring examination satisfied IWE requirements.

You initiated an engineering action item to evaluate this question.

Protective Coating Monitoring and Maintenance Program

  • D/W Interior Service Level I Coating

- Some minor issues identified. Documented results indicated a good quality inspection Electrical Cables and Connections

  • Drywell Cable Inspections

" Good attention to detail & good questioning attitude

" Good engineering planning, prep, and participation

" Excellent cooperation between work group and engineering Inaccessible Medium Voltage Cables

  • Cable Test - as part of the Doble Test on Auxiliary Transformer (bank 4)
  • Some industry experience suggests that large transformer characteristics can de-sensitize the test results regarding cable insulation degradation Buried Piping
  • ESW Pipe Replacement and Tie-in
  • FME control and pipe handling (to protect pipe coating) adequate to ensure a quality installation Structures Monitoring Program
  • Intake tunnel and expansion joints
  • Good hand-offs between night-shift and day-shift engineering No Noteworthy Observations One-Time Inspection Program
  • Isolation Condenser Inspection and UT below the water line Periodic Inspection Program
  • Condensate System expansion joint inspection
  • Fire barrier inspection inside a switchgear Metal Fatigue Program 9 No changes to the high cumulative usage factor components list ANY QUESTIONS for US P 4e-decis~hal Infortion -- Off0ial U y Page 5 of 5 t
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