> New Draft on CRDM Cracking Page 1 of I

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& em If At Forar Repy iso Tr 'e Bx Clnaamwd e mg_42a TrashM ___

Fromm: Rodney X. Cook on 0/20/7,0l0 07:41 AMTo: Prasoon K. Ooyal/TE/irstsnergy@Firatinergy, Frank W.

Kennedy! WFirstEnergy@FirstEnarg, Mark A. US RMeLaughlinTrF~irstEnergy@FinersyW In re DAVID GEISEN C . .I . Exhibitcc: Dale R. WuokkofrE/FirstEnergy@FistEnergy, Dale L. Docket# 1A-05-052

Miller! E/FirstEnergy@FirstEnargy, D"vi R. LodcwoodfrE/irstF~ergy@F nratfCRSubject New Draft on CRDM Cracking Date Marked for ID:I', 2008 (Tr. P. -)Here's the latest draft of the response to the Bulletin. I plan on getting it out into Ev: 2008 (Tr. p.-Green Sheet review today. I still need the JCO and a review of fhe 2000 Date Offered ininspection result description. Through Witnes sPanel: '/ / A

Please let me know any comments you may have as soon as possible.

Thanx

x7782

Se"la 2M3 Draft 81&O.dcb

Action; <kIb REJECTED WITHDRAWN

Date: , 2008 (Tr. P.

CoM v C

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DOCKETEDUSNRC

September 9, 2009 (11:00am)

OFFICE OF SECRETARYRULEMAKINGS AND

ADJUDICATIONS STAFF

http://access.firstenergycorp-cora/mfaiL/DaleRWuokko.nfl75e502a~uf4lba8afE7O&~ 6kOO 26il

-7z51\PLATE & ~SECf 0 -D

Docket Number 50-346

License Number NPF-3

Serial Number 2731

U.S. Nuclear Regulatory CommissionAttention: Document Control DeskWashington, D.C. 20555-ooo I

Subject: Response to NRC Bulletin 2001-01, "Circumferential Cracking of Reactor

Pressure Vessel Head Penetration Nozzles"

Ladies and Gentlemen:

On August 3, 2001, the Nuclear Regulatory Commission (NRC) issued NRC Bulletin2001-01, "Circumferential Cracking of Reactor Pressure Vessel Head PenetrationNozzles." The Bulletin requested information regarding the structural integrity of the..reactor pressure vessel head penetration (VHP) nozzles, including the extent of nozzleý-rz-'leakage and cracking that has been found to date, inspections and repairs that have beencompleted to satisfy applicable regulatory requirements, and the basis for concluding thatplans for future inspections will ensure compliance with applicable regulatorycompliance.

ýý-BNP~)has scheduled VLLP inspections during the upcoming spring 2002 refuelingotge. The FirstEnergy Nuclear Operating Company (FENOC) provides the attached

information for the Dai".'i Besse a. Oprnting Stati_'on .)DBNPSt---

If you have any questions, or require further information, please contact Mr. David H.Lockwood, Manager, Regulatory Affairs, at (419) 321-8450.

Very truly yours,

RMC/

Attachments

FE706-0283

FE706-0283

Docket Number 50-346License Number NPF-3Serial Number 2731Page 2

cc: J. E. Dyer, Regional Administrator, NRC Region IIIS. P. Sands, DB-I NRC/NRR Project ManagerK. S. Zellers, DB- I Senior Resident InspectorUtility Radiological Safety Board

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FE706-0284

FE706-0284

Docket Number 50-346License Number NPF-3 ". , - of -e•-4:r 7 .Serial Number Ves• 1-// 7h•e ,,,n ev tleiAttachment IPage 1 ofo

Response to NRC Bulletin 2001-01 for the Davis-Besse Nuclear Power Station

Thebavis-Bess• Nuclear Power Station (DBNPS) .

EftieFl o;reas(F ) fLCOconee Nquciear Station, U11i1 3 :(ONS3) c•,diti 11n 'Thii 5,••Gluestea Fos k.A 4

plant-specific susceptibility ranking for your plant(s) (including all data used to determine eac ,

ranking) using the PWSCC susceptibility model described in Appendix B to the MiR-44, Part 2,report;P

Resonse: 110 A& a'

,.,e A.a. ,. sd -f,14(,' -3

The DBNPS has bee analyzed for susceptibility relative to (ONS3) using ttiat-erto(PWSCCmdel. ey parameters used in this ranking are included i Attatbnt'2. Tl

r P(( O uari6tiowed that it will take the DBNPS 3 MFPY)of additional operation from March 1, 2001,to reach the same time-at-temperature as ONS3(hn leaking nozzles were discovered in March 2001.

It_ . POwe Yer-The DBNPS falls into the NRC category of plants within 5 EFPY of ONS3.

-- ý-description of the VHP nozzles in your plant(s), including the number, type, inside and outsidediameter, materials of construction, and the minimum distance between VHP nozzleD.Y-"

Response:

The DBNPS has 69 Control Rod Drive Mechanism (CRDM) nozzles of which 61 are used forCRDMs, 7 are spare, and one is used for the Reactor Pressure Vessel (RPV) head vent. Each CRDMnozzleffis constructed of Inconel Alloy 600 and is attached to the RPV head by an Inconel Alloy 182 J-groove weld. The head arrangement and requested nozzle details are provided in Attachment 2.

dscription of the IUv he~aa insulation-type and configuratioi"'o I,',

Respnse:

The DBNPS has metal reflective horizontal vessel head insulation. Metal reflective insulation is usedon the exterior of the vessel from the closure flange down to and including the exterior of the bottomhead dome. Removable metal reflective insulation panels enclose the top head closure flange andstuds. Metal reflective insulation is used on the RPV head. MýSý ýA gap exists between theRPV head and the insulation, the minimum gap being at the dome center f the RPV head, where it isapproximately 2 inches, and will not impede a qualified visual inspection.

FE706-0285

FE706-0285

Docket Number 50-346License Number NPF-3Serial NumberAttachment I - -Page 2 of 4 ;" '\

,/(A !/._____

.d•. escription of the VHP nozzle and RPV head inspections (type, scope, qualificationrequirementsq, and acceptance crikerig) that have been performed at your plant(s) in the past 4 years,and the findings. Include a description of any limitations (insulation or other impediments) to z.-,'accessibility of the bare metal of the RPV head foirisua-l examinations;

Response:

The DBNPS has performed two inspections within the past four years during the 1 IVh Refueling Outage(RFO) in April 1998 and during the 126 RFO in April 2000. The scope of the visual inspection was toinspect the entire head (bare metal) area accessible through the weep holes to identify any boric acidleaks/deposits. The DBNPS also inspected 100% of Control Rod Drive Mechanism (CRDM) flangesfor leaks under the Generic Letter 88-05 program. The results of two recent inspections are describedbelow.

Inspections of the RPV head are performed with the RPV head insulation installed. The servicestructure envelopes the DBNPS RPV head and has 18 openings (weep holes) at the bottom throughwhich inspections are performed. There are 69 CRDM nozzles that penetrate the RPV head. Themetal reflective insulation is located well above the head and does not interfere with the visualinspection. The visual inspection is performed by the use of a small camer.a monted on a wire.po!e.This camera is inserted through the weep holes."j ui pr•vd6,, r,-.j -v 7 . .-- "

1998 Awpctionkeul s &eformed jft/ring I1 lRAFO ord

This inspection showed an uneven layer of boric acid sftcater ovef the head. There were so .lumps of boron, with the color varying from brown to white. The outside diameter of the CRDMtubes showed white streaks, providing evidence of downward flow and attributable to CRDM ,

-.>. .. flange leakage. The head was cleaned by use of a manual scrubber and vacuum ?'The-head ' , .) ,G leaning Was urrt~ by~ny tlil5u ddu ii A uaWdw~ sbsta ~~

g 2000itsnectiont/esults.uierformed urin-T2......The second RVP inspection was conductedA April 2000. Framatome Nuclear Power Services

7 performed a 100% video inspection of CRDM flanges-bove the RPV insulation. Five leaking(1' ~ '~' CRDM flanges were identified at locations Fi0,DP10, CI 1, F8, and G9. The main source of

3 ~ leakage was associated with the D 10 CRD) ositlvW'ewdence existed that drives F8, F10 and:C-: ICl had limited gasket leakage. All/,R._ gaskets were replaced and !N . qlM flange wa,machined. Vjua, in~Pectio•¢ofthe flanges was performed via lexan covers intalk Xoni the service,,

." j ,.4q4 structur ome nbnrc-•d 4&rstals had accumulated on the RPV head insulation beneath the-,. ,' -c leaking tianges. These deposits were cleaned (vacuumed). After cleani area above the

i insulation was videotaped for future use.

Initial inspection of the RPV hea(.ozzles area indicated some accumulation of boric acid. Thebor& Ewid deposits were located beneath the leaking flanges with clear evidence of downwardflow, No visible evidence of nozzle leakage was detected. AVnajority of the nozzles were..inspected. The RPV head was cleaned with demineralized ,,aler, at • ci-. idc An "

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FE706-0286

Docket Number 50-346License Number NPF-3Serial NumberAttachment 1 J o veoIQ LARAý r744'P a g e 3 o f 4 , o / • Z ~ / s • ' f " '

the doseo& nethodL bsequent video inspection of the clean RPV head and nozzles wasperformed for future use. ~~Ax .i ~~. i-

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/;.2/ldescription of the configuration of the missile shield, the CRDM housings and theirsupport/restraint system, and all components, structures, and cabling from the top of the RPV headup to the missile shield. Include the elevations of these items relative to the bottom of the missileshield.

Al Ah-C- &f~ m~11Response:

The service structure bolts to the reactor vessel head. Fan holes are provided to allow forced aircooling of CRDMs. Ductwork connected to two remotely mounted, 100 percent capacity cooling fansis mounted over the fan holes in the service structure. The lower portion of the service structure is alsoprovided with ledges to support the RPV head insulation. The upper portion of the service structurecylinder is provided with a monorail to accommodate chain hoists that are required for stud tensionerhandling. A deck is provided on the service structure to provide a work platform for servicing theCRDMs. This deck also provides the support for the CRDM cooling water manifolds and electricalcables. The deck is composed of individual butted plates with openings to accept seismic clampsprovided with the CRDMs. These seismic plates provide stability for the upper portion of the CRDM.They are fie h ned to the reactor vessel control rod nozzles.--ffpj ..-

S44Lc* CCSoIL

•L4 '

The elevations for the4Ce, including the top of the service structure, are shown in the attached Figure1. The top of the missile shield over the service structure (not shown on the sa") fis at elevation653'0". The missile shield is comprised offconcrete removable panels, each 3!'- x 0' x 3" !.

/ If the susceptibility ranking for your plnt'is within 5 EFPY of ONS3, addressees are requested toprovide the following information:

a/. •ur plans for future inspections (type, scope, qualification requirements, and acceptancecriteria) and the schedule• " .. .

Aft'0The DBNPS 13th RFO is scheduled for April 2002. It is planned to conduct qualified visualinspections of the top RPV head bare metal surface to look for signs of leakage aroundJJle RDMnozzles where they penetrate the RPV head. If any leaks are detected, the source will be etermined,the cracks leading to the leak characterized by a volumetric inspection and the nozzle will be repaired.A flow chart of the inspection p olaniýss iin Figure Details of the inspection plan will bedevelop xQt e-3w-RO.CiZCr ? In,

2 P

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FE706-0287

Docket Number 50-346License Number NPF-3Serial NumberAttachment IPage 4 of 4:

o0ur basis for concluding that the inspections identified in 3.a. will assure that regulatoryrequirements are met (see Applicable Regulatory Requirements section). Include the followingspecific information in this discussion:(1) If your future inspection plans do not include performing inspections before December 31,

2001, provide your basis for concluding that the regulatory requirements discussed in theApplicable Regulatory Requirements section will continue to be met until the inspections areperformed.

(2) If your future inspection plans include only visual inspections, discuss the corrective actionsthat will be taken, including alternative inspection methods (for example, volumetricexamination), if leakage is detected.

Response:

The Applicable Regulatory Requirements section of the Bulletin lists the following regulatoryrequirements and plant commitments as providing the basis for the Bulletin assessment:

* Appendix A to 10 CFR 50, "General Design Criteria for Nuclear Power Plants"

Criterion 14 - "Reactor Coolant Pressure Boundary"

Criterion 31 (6aQture Prevention of Reactor Coolant Boundary," and

Criterion 32 - "Inspection of Reactor Coolant Pressure ary"

• Plant Technical Specifications

1 10 CFR 50.55a, Codes and Standards, which incorporates by reference Section X3, "Rules forInservice Inspection of Nuclear Power Plant Components, of the ASME Boiler and Pressure VesselCode"

* Appendix B of 10 CFR 50, "Quality Assurance Criteria for Nuclear Power Plants and FuelReprocessing Plants," Criteria V IXFa-d ,IT,- --. "•:.O r a 1/,- ci ( ,- 0'S

The following addresses each of these criteria and demonstrates that the criteria will be met for theDBNPS until the inspections are performed

Design Reguirements: 10 CFR 50. Appendix A - General Design Requirments

The Bulletin states:

'The applicable GDC [General Design Criteria] include GDC 14, GDC 31, and GDC 32. GDC 14specifies that the reactor coolant pressure boundary (RCPB) have an extremely low probability ofabnormal leakage, of rapidly propagating failure, and of gross rupture; the presence of cracked andleaking VHP nozzles is not consistent with this GDC. GDC 31 specifies that the probability of rapidly

FE706-0288

FE706-0288

Docket Number 50-346License Number NPF-3Serial NumberAttachment IPage 5 of 4

propagating fracture of the RCPB be minimized; the presence of cracked and leaking VHP nozzles isnot consistent with this GDC. GDC 32 specifies that components which are part of the RCPB have thecapability of being periodically inspected to assess their structural and leaktight integrity; inspectionpractices that do not permit reliable detection of VHP nozzle cracking are not consistent with thisGDC."These referenced criteria state the following:

Criterion 14 - Reactor Coolant Pressure Boundary"The reactor coolant pressure boundary shall be designed, fabricated, erected and tested so as tohave an extremely low probability of abnormal leakage, of rapidly propagating failure, and ofgross rupture."

" Criterion 31 - Fracture Prevention of Reactor Coolant Pressure Boundary7"he reactor coolant pressure boundary shall be designed with sufficient margin to assure thatwhen stressed under operating, maintenance, testing, and postulated accident conditions (1) theboundary behaves in a non-brittle manner, and (2) the probability of rapidly propagating fractureis minimized. The design shall reflect consideration of service temperatures and other conditions ofthe boundary material under operating, maintenance, testing and postulated accident conditionsand the uncertainties in determining (1) material properties, (2) the effects of Irradiation onmaterial properties, (3) residual, steady state and transient d stresses, and ()flaw siz6.

" Criterion 32 - Inspection of Reactor Coolant Pressure Boundary"Components which are part of the reactor coolant pressure boundary shall be designed to permit(1) periodic inspection and testing of important areas and features to assess their structural andleak tight integrity, and (2) an appropriate material surveillance program for the reactor pressureb o nday.V-5 541

During licensing of the DBNPS it was demonstrated that the design of the reactor coolant pressureboundary meets these requirements. The following demonstrates compliance with the design criteriafor the cracking if the RPV head nozzles.

* Pressurized water reactors licensed both before and after issuance of Appendix A to Part 50 (1971)complied with these criteria in part by: 1) selecting Alloy 600, and other austenitic materials withexcellent corrosion resistance and extremely high fracture toughness, for reactor coolant pressureboundary materials, and 2) following ASME Codes and Standards and other applicablerequirements for fabrication, erection, and testing of the pressure boundary parts. NRC reviews ofoperating license submittals subsequent to issuance of Appendix A included evaluating designs forcompliance with the General Design Criteria.

" Although stress corrosion cracking of primary coolant system penetrations was not originallyanticipated during plant design, it has occurred in the RPV top head nozzles at some plants. Thesuitability of the originally selected materials has been confirmed. The robustness of the design hasbeen demonstrated by the small amounts of the leakage that has occurred and by the fact that noneof the cracks in Alloy 600 reactor coolant pressure boundary materials has rapidly propagated orresulted in catastrophic failure or gross rupture. Given the inherently high fracture toughness and

FE706-0289

FE706-0289

Docket Number 50-346License Number NPF-3Serial Number

Attachment IPage 6 of 4

flaw tolerance of the Alloy 600 material there is indeed an extremely low p[roba ility-of a rapidlypropagating failure and gross rupture. It should be noted that the earlier v &i:os fthe GDCs arein terms of extremely low probability of gross rupture or significant leakage throughout the designlife.The ASME requirement for the J-groove CRDM welds specifies a visual examination of 25% ofthe penetrations for leakage during testing. The component was designed for that inspection. Theexamination which is conducted on the bare RPV head is capable of assessing the structural andleak tight integrity of the head penetrations. Qualified visual inspection and volumetricexamination can be performed using specialized tools.

Therefore, the requirements established for design, fracture toughness, and inspectability in GDC 14,31, and 32, respectively, were satisfied during the initial licensing review for the DBNPS, and continueto be satisfied during operation even in the presence of a potential for stress corrosion cracking of theRPV head penetrations.

Operating Requiremene 0 CFR 50.36 - echnical Scifications

The Bulletin states:

"Plant technical specifications pertain to the issue of VHP nozzle cracking insofar as they require nothrough-wall reactor coolant system leakage."

10CFR 50.36 contains requirements for Plant Technical Specifications. Paragraphs 2 and 3 of 10 CFR50.36 are particularly relevant:

(C)IOCFR 50.36v(2) Limiting Conditions for Operation,,

(E)"Limiting conditions for operation are the lowest functional capability or performance levels ofequipment required for safe operation of the facility. When a limiting condition for operation of anuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial actionpermitted by the technical specifications until the condition can be met.

(&)4 technical specification limiting condition for operation of a nuclear reactor must be establishedfor each item meeting oneef the following criteria:

(4Criterion 3: A structure, system, or component that is part of the primary success path and whichfunctions or actuates to mitigate a design basis accident or transient that either assumes the failureof or presents a challenge to the integrity of a fission product barrier.

UO)Criterion 4: A structure, systep1 component which operating experience or probabilistic riskassessment has shown to be sagnficant to public health and safety.

FE706-0290

FE706-0290

Docket Number 50-346License Number NPF-3Serial NumberAttachment 1Page 7 6- )

10 CFR 50.36 (3) Surveillance Requirements :"Surveillance requirements are requirements relating to test, calibration, or inspection to assurethat the necessary quality of systems and components is maintained, that facility operation will bewithin safety limits, and that the limiting conditionW will be met. " -9

AY, Oerj~tV-&.1-The reactor coolant pressure boundary provides one of the critical barriep for maintaining theintegrity of the physical barriers that guard against the uncontrolled release of radioactivity.Therefore, plant technical specifications generally include a requirement and associated actionstatements addressing reactor coolant pressure boundary leakage. The limits for PWR reactorcoolant pressure boundary leakage are typically stated in terms of the amount of leakage, e.g., Igallon per minute for unidentified leakage; 5-10 gpm for identified leakage; and no leakage froma non-isolable fault in the reactor coolant system pressure boundary.

Leaks from Alloy 600 RVP head penetrations due to PWSCC have been well below the sensitivity ofon-line leakage detection systems. Plants have evaluated this condition and have determined that theappropriate inspections are bare-metal visual inspections for boric acid deposits during plantshutdowns and/or non-destructive examination (NDE) of the CRDMs. If leakage or unacceptableindications are found, the defect must be repaired before the plant goes back on line. If through-wallboundary leaks of the CRDMs increase to the point where they are detected by the on-line leakdetection systems, then the leak must be evaluated per the specified acceptance criteria, and the plantbe shut down if the leak is determined to be a pressure boundary leak.

Inspection Requirements: 10 CFR 50,55a and ASME Section XI

The Bulletin states:

"NRC regulations at 10 CFR 50.55a state that ASME Class 1 components (which include VIPnozzles) must meet the requiret);4 Section X) of the ASME Boiler and Pressure Vessel Code.Table IWA-2500-1 [IWB-25/V0(lofection XI of the ASME Code provides examinationrequirements for VHP nozes er~ences IWB-3522 for acceptance standards. IWB-3522.1(c) and(d) specify that conditions requiring correction include the detection of leakage from insulated

c anddor accumulated residues on the surfaces of components, insulation, or floor areas whichmay reveal evidence of borated water leakage, with leakage defined as "the through-wall leakage thatpenetrates the pressure retaining membrane." Therefore, 10 CFR 50.55a, through its reference to theASME Code, does not permit through-wall cracking of VHIP nozzles.3 -

"For through-wall leakage identified by visual examinations in accordance with the ASME Code,acceptance standards for the identified degradation are provided in IWB-3142. Specifically,supIlemental examination (by surtfce or volumetric examination), corrective measures or repairs,

'An erratum appears to exist in the Bulletin. Table IWA-2500-1 is cited, but does not exist. It appears

the citation should have been IWB-2500-1

FE706-0291

FE706-0291

Docket Number 50-346License Number NPF-3Serial NumberAttachment IPage 8 of 4

analytical evaluation, and replacement provide methods for determining the acceptability of degradedcomponents."

10 CFR 50.55a requires that inservice inspection and testing be performed per the requirements of theASME BoiljUld Pressure Vessel Code, Section XI, "Inservice Inspection of Nuclear PlantCompont .""Stion XI contains applicable rules for examination, evaluation and repair of code classcomponnts, imcluding the reactor coolant pressure boundary.

Requirements for partial penetration welds attaching CRDM housings to the reactor vessel headare contained in Table IWB-2500-1, Examination Category B-E, Pressure Retaining PartialPenetration Welds in Vessels, Items Numbers: B4. 10, Partial Penetration Welds; B4.1 1, VesselNozzles; B4.12, CRDM Nozzles; and B4.13, Instrumentation Nozzles. The Code requires a VT-2"visual examination" of 25% of the CRDM nozzles from the external surface. Since the head isinsulated, and the nozzles do not represent a bolted flange, paragraph IWA-5242(b) permits theseinspections to be performed with the insulation left in place.

All plants, including the DBNPS, perform visual inspections for evidence of leakage by examining theRPV head surface, or the insulation per the requirements of NRC Generic Letter 88-05, "Boric AcidCorrosion of Carbon Steel Reactor Pressure Boundary Components in PWR.Plants." Some plantshave conducted inspections beyond those required by Section XI and NRC Generic Letter 88-05.These inspections have included visual examinations of 100% of the bare metal surfaces of the RPVhead; eddy current and liquid penetrant surface examinations; and volumetric examinations of thenozzles. These supplemental inspections coupled with the evaluations of cracking that has been foundare considered to have provided a defense-in-depth approach for investigating and resolving this issue.As discussed previously, additional effort is underway to develop alternative inspection and analysistools.

The acceptance standard for the visual examination is found in paragraph IWA-5250, "Corrective (9Measures." Paragraph IWA-5250 requires repair or replacement of the affected part if a through-wallleak is found and requires an assessment of damage, if any, associated with corrosion ofsteel components by boric acid. No plant has returned to service after finding a leak from a RPVtop head nozzle without first having repaired the nozzle.

Flaws identified by NDE methods that are beyond current requirements are evaluated in accordancewith the flaw evaluation rules for piping contained in Section X) of the ASME Code. This approachhas been accepted by the NRC. Any flaw not meeting the requirements for the intended service periodwould be repaired prior to returning it to service.

Repairs to RPV head nozzles have been performed in accordance with Section XI requirements, NRC-approved ASME Code Case requirements, or an alternative repair or replacement method approved bythe NRC.

FE706-0292

FE706-0292

Docket Number 50-346License Number NPF-3Serial NumberAttachment IPage 9 of4 (4)

The DBNPS complies with these ASME Code requirements through implementation of the InseiceInspection Program. If a VT-2 examination detects the conditions described by IWB-3522. 1 and (d),corrective actions will be performed in accordance with the DBNPS corrective action program. Nonew plant actions are necessary to satisfy the regulatory criteria.

Quality Assurance Requirements: 10 CFR 50. Appendix B

The Bulletin states:

"Criterion IX of Appendix B to 10 CFR Part 50 states that special processes, including nondestructivetesting, shall be controlled and accomplished by qualified personnel using qualified procedures inaccordance with applicable codes, standards, specifications, criteria, and other special requirements.Within the context of providing assurance of the structural integrity of VHP nozzles, specialrequirements for visual examination would generally require the use of a qualified visual examinationmethod. Such a method is one that a plant-specific analysis has demonstrated will result in sufficientleakage to the RPV head surface for a through-wall crack in a VHP nozzle, and that the resultantleakage provides a detectable deposit on the RPV head. The analysis would have to consider, forexample, the as-built configuration of the VH-Ps and the capability to reliably detect and accuratelycharacterize the source of the leakage, considering the presence of insulation, preexisting deposits onthe RPV head, and other factors that could interfere with the detection of leakage. Similarly, specialrequirements for volumetric examination would generally require the use of a qualified volumetricexamination method, for example, one that has a demonstrated capability to reliably detect cracking onthe OD of the VHP nozzle above the J-groove weld."

The design shrink fit of the CRDM nozzles at the DBNPS is similar to the design shrink fit of the ONSunits indicating that through wall cracking of the nozzles of the magnitude seen at ONS shouldproduce visually detectable evidence of leakage on the RPV head. The qualified visual inspection andthe personnel involved in the evaluation of the results will be VT-2 qualified and familiar with theanticipated type of indication that any leakage would cause. Any other NDE techniques and assiated-.equipment that may be required is presently being developed and should be qualified for the DBNPS13RFO in the spring of 2002.

The Bulletin further states:

"Criterion V of Appendix B to 10 CFR Part 50 states that activities affecting quality shall beprescribed by documented instructions, procedures, or drawings, of a type appropriate to thecircumstances and shall be accomplished in accordance with these instructions, procedures, ordrawings. Criterion V further states that instructions, procedures, or drawings shall include appropriatequantitative or qualitative acceptance criteria for determining that important activities have beensatisfactorily accomplished. Visual and volumetric e.xa o. nozzles are activities thatshould be documented inaccordance h esere uiremen .' . I ppen 1, requires that

ciensees have a quality assurance program that addressesd si pecti n, monitoring, andcorrective actionFE-70-69--3

-r - / FE706-0293

FE706-0293

Docket Number 50-346License Number NPF-3Serial NumberAttachment IPage 10 of 4

The efforts undertaken to inspect, evaluate, and /or repair the DBNPS RPV head penetrations will beconducted and documented in accordance with procedures which comply with the FENOC QualityAssurance Program and Criterion V of 10 CFR 50, Appendix B.

The final 0iterion cited by the Bulletin is stated as follows:

"Criterion XVI of Appendix B to 10 CFR Part 50 states that measures shall be established to assurethat conditions adverse to quality are promptly identified and corrected. For significant conditionsadverse to quality, the measures taken shall include root cause determination and corrective action topreclude repetition of the adverse conditions. For cracking of VHP nozzles, the root causedetermination is important to understanding the nature of the degradation present and the requiredactions to mitigate futur qcking. These actions could include proactive inspections and repair ofdegraded VHP nozzles.= lull

In addressing Criterion XVI, there are two important attributes pertinent to RPV CRDM nozzlfr--cracking.

First, Criterion XVI states '*easures shall be established to assure that conditions NdiVerse to qualityx"are promptly identified ja rrected." This criterion is partially met by the L&RP-sawareness ofindustry experience, an; ;en implemented in this manner in the DBNPS corrective actionprogram whereby indust' y'xperience is evaluated for applicability ta4)BNI18 and the applicablecorrective actions, as needed are determined. This is consistent with the NRC's genericcommunication process, implernented'&b-y information Notices, which reports industry experience,but does not require a response to NRC. Licensees are expected to evaluate the applicability of theinformation contained in the Notice and document a specific assessment for possible NRC review.

Criterion XVI provides the objectives and goals of the corrective action program, but leaves to thelicensee the responsibility for determining the specific process to mcqnplish these objectives andgoals. With regard to the Bulletin response, Criterion XVI doeshptbvide specific guidance as towhat is an appropriate response, but rather, the licensee is responle for determining actionsnecessqt- maintain public health and safety. In this particular instance, the licensee must justify itsaction • ddressing the PWSCC of RPV head nozzles. Furthermore, the regulatory criteria of10 CFRýI .109(a)(7) provides supporting evidence when it states "... if there are two or more ways toachieve compliance.. .then ordinarily the applicant or licensee is free to '•the way which best suitsits purposes."

The second ttribute of Crjte,&nXV state ni ficant conditions adverse to quality, themeasu.......•i,'ll• .. c and corrective action taken topreclude reptio Bulletin suggests that for RPV head nozzle cracking, the root causedetermination is ih p6'rtant to understanding the nature of the degradation and the required actions tomitigate future cracking. As part of the DBNPS corrective action program, determination of the causeof the PWSCC in the RPV head nozzles, either through the DBNPS's own efforts or as part of aninoty effort, would be performed, if cracks are detected. However, if no cracks in the heads are

) etified through reasonable quality assurance measures or inspection and monitoring programs,

FE706-0294

FE706-0294

Docket Number 50-346License Number NPF-3Serial NumberAttachment 1Page II of 4-'

7this criterion would not require specific action on the part of DBNPS for remaining in compliance withthe regulation.

In summary, the integrated industry approach to inspection, monitoring, cause determination, andresolution of the identified CRDM nozzle cracking i in compliance with the performanijj)based objectives of 10 CFR 50, Appendix B.

(1)If your future inspection plans do not include performing inspections before December 31, 2001,provide your basis for concluding that the regulatory requirements discussed in the ApplicableRegulatory Requirements section will continue to be met until the inspections are performed.(2) If your future inspection plans include only visual inspections, discuss the corrective actions thatwill be taken, including alternative inspection methods (for example, volumetric examination), ifleakage is detected.

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The DBNP rimnsto perform inspections of the RPV head and CRDM nozzles as recommended byMIRP-,.;rThe inspections will consist of qualified visual inspections of the top head bare metalsurface at the 1P3t RFO scheduled for April 2002. If any leaks are detected, the source will bedetermined, the cracks leading to the leak characterized by volumetric examination and the nozzle willbe repaired.

.Addressees are requested to provide U Rtouowmg reformation within 30 days after plant restart-following the next refueling outage:

a. a description of the extent of VHP nozzle leakage and cracking detected at your plant,including the number, location, size, and nature of each crack detected;

b. if cracking is identified, a description of the inspections (type, scope, qualificationrequirements, and acceptance criteria), repairs, and other corrective actions you have taken tosatisfy applicable regulatory requirements. This information is requested only if there are anychanges from prior information submitted in accordance with this bulletin.

Response:

The DBNPS will provide the NRC with the following information within 30 days after plant restartfollowing the 13th RFO scheduled to begin in April 2002 if any leaks or cracks are discovered:

a. A description of the extent of RPV head nozzle leakage and cracking. This information willinclude the number, location, size and nature of each crack detected.

b. A description of the inspections (type, scope, qualification requirements, and acceptancecriteria), repairs and other corrective actions taken to satisfy applicable regulatoryrequirements. FE706-0295

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FE706-0295

Docket Number 50-346License Number NPF-3Serial NumberAttachment 1Page 12 of 4

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FE706-0296

FE706-0296

,Docket Number 50-346License Number NPF-3Serial Number 2731Attachment 2Page 1 of

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FE706-029 7

FE706-0297

Docket Number 50-346License Number NPF-3Serial Number 2731Attachment 3Page 1 of 1

COMMITMENT LIST

The following list identifies those actions committed to by the Davis-Besse NuclearPower Station (DBNPS) in this document. Any other actions discussed in the submittalrepresent intended or planned actions by the DBNPS. They are described only forinformation and are not regulatory commitments. Please notify the Manager - RegulatoryAffairs ((419)-321-8450)) at the DBNPS of any questions regarding this document orassociated regulatory commitments.

CONIMITMENTS DUE DATE

The DBNPS plans to perform inspections of the V head 13" RFOand CRDM nozzles as recommended by MRP48. Theinspections will consist of qualified visual insp- ions ofthe top head bare metal surface at the 13'h RFO scheduledfor April 2002. If any leaks are detected, the source will bedetermined, the cracks leading to the leak characterized by V/ /u.,A c'ý - gi OD.V.--

(•T)'•dUltct•r~c •,,h.• T).and the nozzle will berepaired f-.f)The DBNPS will provide the NRC with the following 30 days following end of

information within 30 days after plant restart following the 13'h 13'h RFO

RFO scheduled to begin in April 2002 if any leaks or cracks arediscovered:

a. A description of the extent of RPV head nozzle leakageand crackingif.deeeted-. This information will includethe number, location, size and nature of each crackdetected.

b. A description of the inspections (type, scope,qualification requirements, and acceptance criteria),repairs and other corrective actions taken to satisfyapplicable regulatory requirements.

FE706-0298

FE706-0298