ML091480449

License Renewal Commitments Inspection, Exit Meeting - Dec 23, 2008, Rev 8

ML091480449
Person / Time
Site:	Oyster Creek
Issue date:	12/22/2008
From:	NRC Region 1
To:
References
FOIA/PA-2009-0070
Download: ML091480449 (4)

Text

Pr-Deq?ý4onof0(ma in /-;ý Ký Oyster Creek License Renewal Commitments Inspection Exit Meeting - Dec 23, 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 quitefhelpful Special Thanks 9 Pete Tamburro (LR Program Owner) 9 Chris Hawkins (NDE Level-ill)

• Cal Taylor & Jhansi Kandasamy Inspection Schedule Slippage

• LR outage schedule slipped due to unexpected issues

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

" Bay 11 Coating Blisters

• Bay 3 Moisture Barrier, Seal Problem

• Cavity Leakage, and Water Intrusionihnt6i4 bays

• As a result, our inspection ran into a 2nd on-siie week and a 3rd in-office week Documentation Team Report 45 days after the Exit Meeting (early Feb)

Exec Surmmanry.of Inspection Results$;,

• Observed actions to evaluate primary containment structural integrity

• Observed selected ativ'ities described in SER Appendix-A, "Commitments for LR" Because the Renewed License has not been issued With respect to proposed SER commitments

• No assessment of implementation or effectiveness will be documented Factual Based Observations of activities will be documented

• The conclusions of PNQP--08-012 remain unchanged

• Reviewed 2 change "packages for proposed activities described in SER App-A

• A summary of the change will be documented

• No assessment of administrative controls was made

• No evaluation of technical adequacy was made

• An Unresolved Item (URI) will be opened to evaluate whether existing current licensing basis commitments were not adequately performed, and to assess the safety significance for any related performance deficiency. The issues for follow-up are strippable coating de-lamination, reactor cavity trough drain monitoring, and sand bed drain monitoring.

Pre-*cisi nal Info/m /on -- O 7 ial UA O/UY OC LRI 2008-07_Exit Notesrev-8.doc I of 4 / - 5 O Updated 12-22-08

Key Inspection Observations (1) Proposed SER App-A Item 27, ASME Section XI, Subsection IWE, Part (2)

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

Strippable Coating De-lamination

" From Oct 29 to Nov 6, the strippable coating limited leakage into the cavity trough drain at < 1 gpm

" On Nov 6, the observed leakage rate in the cavity trough drain took a~step change to 4 to 6 gpm

• Water puddles were subsequently identified in 4 sand bed bays

• AmerGen identified several likely or contributing causes

• A portable water filtration unit was improperly placed in the reactor cavity, which resulted in flow discharged directly on the strippable coating

• An oil spill into the cavity may have affected the coating integrity

• No post installation inspection of the coating had-been performed

• AmerGen stated follow-up UTs will re-evaluate the drywell shell next outage.

(2) Proposed SER App-A Item 27, ASME Section XI, Subsection IWE, Part (3)

Reactor cavity seal leakage trough drainsand the drywell sand bed region drains will be monitored for leakage. Periodically.

Cavity Trough Drain Line Found Isolated

" On Oct 27, the drain line was isolated to install a tygon hose to allow drain flow to be monitored

" On Oct 28, the reactor cavity was filled

" Drain line flow was monitored frequently during cavity flood-up, and daily thereafter

" On Oct 29, a boroscope examination identified the drain line isolation valve had been left closed

" When the drain line isolation valve was opened, about 3 gallons of water drained out, then the drain flow subsided to about an 1/8 inch stream (< 1 gpm)

Drain Flow Monitoring Plan

• AmerGen stated a calculation determined cavity trough drain flow of less than 60 gpm would not result in trough overflow into the gap between the drywell shield wall and the drywell shell

• AmerGen had a pre-approved Action Plan for monitoring cavity & sand bed drains

• Per Action Plan, if drain flow > 5 gpm, then monitor every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />

• Per Actioni Plan, if drain flow> 12 gpm, then monitor sand bed poly bottles every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> If drain flow> 12 gpm and water found in sand bed poly bottles, then enter & inspection sand beds Water Found in Sand Bed Bays

" On Nov 6, the strippable coating started to de-laminate

" Trough drain flow took a step change from < 1 gpm to approx 4 to 6 gpm

" Increased monitoring trough drain to 2-hr and sand bed poly bottles to 4-hr (not required by Action Plan)

" On Nov 8, workers inside sand bed bay 11 identified dripping water

" Subsequently,. water puddles were identified in 4 sand bed bays

• After cavity was drained, inspected all sand bed bays -- No deficiencies identified

• Sand bed bays were originally scheduled to have been closed by Nov 2

• On Nov 15, after cavity was drained, water was found in sand bed bay 11 poly bottle Pddec"iona /lfor aitio* -- "icial se OC LRI 2008-07-Exit Notes-rev-8.doc 2 of 4 Updated 12-22-08

.De na 4fr o -ZTl a <I0fn (3) Proposed SER App-A Item 27, ASME Section XI, Subsection IWE, Part (3)

Sand bed region drains will be monitored daily during refueling outages.

Sand Bed Drain Poly Bottles Not Connected

• Sand bed drains were remotely monitored by checking poly bottles, attached via tygon tubing to funnels hanging below the drain lines

• The drains were not directly observed

• After the reactor cavity was drained, 2 of the 5 tygon tubes were found.disconnected', laying on the floor

• Sand Bed Bay 11 drain poly bottle was empty during each daily check until Nov 15 (cavity was drained on Nov 12), when itwas found full (> 4 gallons). Bay 11 was entered, visually inspected, and found dry.

(4) Proposed SER App-A Item 27, ASME Section XI, Subsection IWE, Part (4)

Perform visual inspections of epoxy coating on the drywell external surfaces in the sand bed bays Directly observed conditions of the drywell shell epoxy coating in selected sand bed bays

• Observed AmerGen's activities to evaluate the epoxy coating Sand, Bed Bay 11 Blisters

• Observed activities to evaluate and repair blisters found in Bay 11

• 1 small 1/4 inch broken blister identified, with a 6" rust stain

• 3 smaller unbroken blisters were identified by the NRC, during initial investigation

• All 4 blisters were within a 1-2 inchlessquare area, and .all were evaluated and fixed

• As an extent of condition, 4 bays re-inspected by a different NDE level-Il inspector, nothing found

• AmerGen estimated corrosion of - 3 mils had occurred over about a 16 year period

>>> also identified and fixed a area that appeared to NOT havethe 3rd epoxy coating 2006 Inspection Did Not Identify the Rust Stain

• In follow-up, AmerGen reviewed a 2006 video and identified the same 6" rust stain in the 2006 video

• During 2006 coatings inspection, no deficiencies were identified (5) Proposed SER App-A Item 27, ASME Section XI, Subsection IWE, Part (12)

The externaldrywell shell moisture barrier seal, between the shell and the sand bed floor, will be inspected:w'hen the epoxy coating is inspected.

• Directly observed conditions of the.drywell shell moisture barrier in selected sand bed bays

• Observed AmerGen's activities to evaluate the moisture barrier

• AmerGen identified deficiencies in 7 of the 10 sand bed bays, including

" Surface cracks

" Partial separation of the seal from the shell, or the floor

• AmerGen determined the moisture barrier function was not impaired, because no cracks or separation fully penetrated the seal. All deficiencies were repaired.

Sand Bed Bay 3 Seal Crack and Rust Stain

" Observed activities to evaluate and repair the moisture barrier seal in Bay 3

" The seal had rust stains on the surface, below the identified crack

" When the seal was excavated, some drywell shell surface corrosion was identified

" Seal crack and surface rust were repaired

• Laboratory analysis determined there was inadequate epoxy cure, an original 1992 installation issue 2006 Inspection Did Not Identify Any Seal Cracks

• During 2006 seal inspections, no deficiencies were identified Pr /q6/i nal M7an-Pr/-de ý/aý//

OC LRI 2008-07-Exit Notes-rev-8.doc 3 of 4 Updated 12-22-08

P/r-Deci on nforýo -- Off/ial V4 ly<?*

(6) Proposed SER App-A Item 27, ASME Section XI, Subsection IWE Drywell In-service Inspection - Ultrasonic Thickness Measurements

" Observed AmerGen perform drywell shell UT thickness measurements

" Observed AmerGen evaluate the UT data (2000 separate UT readings)

" AmerGen determined that all of the UT data satisfied acceptance criteria, based on current licensing basis design requirements, for the thickness of the steel plate

• AmerGen did not identify any significant conditions affecting the drywell shell structural integrity

• AmerGen did not identify any on-going corrosion or corrosion trend, based on the UT examinations

" AmerGen did not identify any statistically significant deviations from 2006 UT data values No Noteworthy Observations Protective Coating Monitoring and Maintenance Program

• D/W Interior Service Level I Coating Electrical Cables and Connections

• Drywell Cable Inspections Inaccessible Medium Voltage Cables

• Cable Test - as part of the Doble Test on Auxiliary Tr'ansformer (bank 4)

Buried Piping

• ESW Pipe Replacement and Tie-in 1.

Structures Monitoring Program

• Intake tunnel and expansion joints One-Time Inspection Program

• Isolation Condenserlnspection and UT below the*water line Periodic Inspection Program

" Condensate System expansion joint inspection

" Fire barrier inspection inside a switchgear Metal Fatigue Program

• No changes to the high cumulative usage factor components list ANY QUESTIONS for US Prdecis ina, !,orm/ion -- O7 cial UJe Of OC LRI 2008-07 Exit Notes rev-8.doc 4 of 4 o / Updated 12-22 -08