2CAN102103, Response to Request for Additional Information Concerning Relief Request ANO2-R&R-012 Support the Repair of the Reactor Vessel Closure Head Penetration 46

Response to Request for Additional Information Concerning Relief Request ANO2-R&R-012 Support the Repair of the Reactor Vessel Closure Head Penetration 46

ML21285A326
Person / Time
Site:	Arkansas Nuclear
Issue date:	10/12/2021
From:	Gaston R Entergy Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2CAN102103
Download: ML21285A326 (17)

Text

10 CFR 50.55a(z)(1) 2CAN102103 October 12, 2021 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Response to Request for Additional Information Concerning Relief Request ANO2-R&R-012 Support the Repair of the Reactor Vessel Closure Head Penetration #46 Arkansas Nuclear One, Unit 2 NRC Docket No. 50-368 Renewed Facility Operating License No. NPF-6 Entergy Operations, Inc. (Entergy) submitted Relief Request ANO2-R&R-012 for Arkansas Nuclear One, Unit 2 (ANO-2) via Reference 1. A flaw located in the Reactor Vessel Closure Head, Penetration #46 was determined to be unacceptable based on requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). In Reference 1, Entergy proposed an alternative to the requirements of the 1968 Edition with Addenda through Summer 1970 of ASME Code Section III, N-462.4(d), Figure N-462.4(d) as part of the repair strategy.

The U.S. Nuclear Regulatory Commission (NRC) staff has determined that additional information is needed to complete its review (Reference 2). The requested information is provided in response to this request is provided in the Enclosure.

There are no new regulatory commitments established in this submittal.

Entergy Operations, Inc.

1340 Echelon Parkway Jackson, MS 39213 Tel 601-368-5138 Ron Gaston Director, Nuclear Licensing

- Entergy

2CAN102103 Page 2 of 2 If there are any questions or if additional information is needed, please contact Riley Keele, Manager, Regulatory Assurance, Arkansas Nuclear One, at 479-858-7826.

Respectfully, Ron Gaston RWG/rwc

References:

1. Entergy Operations, Inc. (Entergy) letter to the U. S. Nuclear Regulatory Commission (NRC), " Relief Request ANO2-R&R-012 - Support the Repair of the Reactor Vessel Closure Head Penetration #46," (2CAN102102), ML21283A001, dated October 10, 2021.

2. T. Wengert (NRC email to R. D. Keele, Jr. (Entergy), " ANO-2 Final RAI RE: Relief Request ANO2-R&R-012 Concerning RV Closure Head Penetration #46,"

(2CNA102101), dated October 11, 2021.

Enclosure:

Response to Request for Additional Information Related to Relief Request ANO2-R&R-012

Attachment:

Draft Special Implementation Instructions cc:

NRC Region IV Regional Administrator NRC Senior Resident Inspector - Arkansas Nuclear One NRC Project Manager - Arkansas Nuclear One Designated Arkansas State Official Ronald W.

Gaston Digitally signed by Ronald W. Gaston Date: 2021.10.12 18:25:14 -05'00' A

Enclosure 2CAN102103 Response to Request for Additional Information Related to Relief Request ANO2-R&R-012

2CAN102103 Enclosure Page 1 of 10 RESPONSE TO REQUEST FOR ADDITTIONAL INFORMATION RELATED TO RELIEF REQUEST ANO2-R&R-012 By Letter No. 2CAN102102 dated October 10, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21283A001), Entergy Operations, Inc. (the licensee) submitted Relief Request ANO2-R&R-012 for Arkansas Nuclear One, Unit 2 (ANO-2).

In ANO2-R&R-012, the licensee stated that a flaw located in Reactor Vessel Closure Head Penetration #46 nozzle was determined to be unacceptable based on requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code).

The licensee stated that it has developed a strategy to perform a local excavation of penetration Nozzle #46 and the adjacent J-groove weld to remove the indication to repair this nozzle. In ANO2-R&R-012, the licensee proposed an alternative to the requirements of the 1968 Edition with Addenda through Summer 1970 of ASME Code Section III, N-462.4(d), Figure N-462.4(d)

Attachment of Connections Using Partial Penetration Welds, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Section 50.55a(z)(1), Acceptable level of quality and safety.

The U.S. Nuclear Regulatory Commission (NRC, the Commission) staff has determined that additional information is needed to complete its review, as described below.

Regulatory Basis The inservice inspection (ISI) of the ASME Code,Section XI, Class 1, 2 and 3 components shall be performed in accordance with the requirements of Section XI, Rules for In-service Inspection of Nuclear Power Plant Components, of the ASME Code and applicable editions and addenda as required by 10 CFR Part 50 Paragraph 50.55a(g), except where specific written relief has been granted or proposed alternative authorized by the Commission. In order to assess the licensees proposed alternative, the NRC staff requires the following additional information to complete the review.

Request for Additional Information (RAI)

RAI-1 Proprietary Withholding Assertion With regard to the proprietary markings of the paragraphs on the bottom of page 8 and the top of page 9 of Enclosure 1 of the licensees submittal, the licensee has marked certain Conclusions paragraphs as proprietary. However, this is a summary, which does not disclose the specific licensee calculation. The NRC staff requests justification for the licensees basis for meeting the requirements of 10 CFR 2.390, Public inspections, exemptions, requests for withholding, for proprietary withholding of these paragraphs in accordance with Enclosure 3 of the licensees submittal.

Entergy's Response The paragraphs that are the subject of this request were reviewed. It was determined to rewrite them such they are not proprietary. See the revised text below.

The analyses performed above are used to develop an acceptable excavation region in the nozzle and J-groove weld. For the top portion of the nozzle, the grinding process will

2CAN102103 Enclosure Page 2 of 10 limit the material removed radially from the outside surface of the nozzle. Additionally, grinding of the nozzle and the J-groove weld will not extend above the elevation as determined in the analysis relative to the thread relief datum. This provides an additional grinding allowance above the top of the indication. In order to accommodate an angular excavation below the indication, a lower bound elevation from the datum will be used to ensure the minimum wall thickness.

The excavated area shall be smooth with no sudden or sharp transitions and shall be blended to the surrounding areas. The weld for Penetration #46 with an excavation within these dimensions provides greater structural margin against nozzle blowoff than the minimum provided by the design rules of ASME Section III. Views of an example proposed excavation are shown in the analysis that fully removes the indication based on the data provided in Ultrasonic Test (UT) report. The actual final excavation may vary slightly from these examples but be bound by limits discussed above. The analysis presented above addresses typical stresses that would exist in the excavated weld and nozzle as it relates to steady state loading and provides justification for operating for one fuel cycle.

RAI-2 Documenting and Confirming Excavation The NRC staff requests information concerning the maximum dimensions of the excavation as described in the licensees proposed alternative in paragraph in Section 5 of the submittal. The maximum dimensions of the excavation, or limits, should be bound by the licensees calculations and the licensees statement, If not, Entergy will continue to excavate until the limits described above are reached or a successful PT [liquid dye penetrant examination] is achieved prior to reaching the limits.

a. Provide the maximum allowable dimension of excavation for Nozzle #46 and the adjacent J-groove weld including the vertical length, radial depth, and circumference under this alternative.

Entergy's Response Figure 3 of Reference 1 provides the best depiction of the allowable excavation window. The maximum depth will be 0.35 inch radially from the outside diameter to maintain the tmin values provided in Reference 1. The vertical (axial distance along nozzle) length of the grinding window will begin 0.25 inch from the referenced datum and extend to the top of the indication (0.78 inch from datum). From this point a grinding allowance of 0.12 inch above the top of the indication is provided. This provides a total excavation height of 0.65 inch along the axial nozzle length.

The evaluation in Reference 1 considered a circumference length based on 20º in evaluating the reduction of the weld area (or approximately 0.7 inch). The circumference in the nozzle (outside of the weld area) is not expressly limited since the basis for material removal in this area is that the tmin will be maintained and therefore not sensitive to limiting the circumference of material removed. It is anticipated to be in approximately the same width as the weld section excavated but may be larger for blending /

smoothing during the excavation.

2CAN102103 Enclosure Page 3 of 10

b. Describe the process to document and confirm the actual excavation, such as in non-destructive evaluation (NDE) reports, or corrective action documentation. The information should include the final dimensions of the weld including ultrasonic testing (UT) records demonstrating final weld height, photographs of acceptable NDE results (e.g., PT White), and the as-left condition of Nozzle #46 and the adjacent J-groove weld. This information will be subject to NRC inspection, as appropriate.

Entergy's Response The Engineering Change (EC) to implement the excavation is prepared but will not be fully reviewed or issued until the relief request is completed. Therefore, the draft special implementation instructions are attached to this enclosure. These instructions contain the pertinent controls.

RAI-3 Liquid Dye Penetrant Clarifications In Part 3 of the licensees submittal, Other Considerations, the licensee notes the intended use of NB-5000 of the 1992 Edition of Section III for performance of the post-excavation liquid dye penetrant examination (PT). This examination must be able to identify any remnant primary water stress corrosion cracking or other defects that may have contributed to, or be part of, the overall defect and have been left in the nozzle after the excavation. The licensee is requested to:

a. Justify that the use of NB-5000 of the 1992 Edition of Section III for the PT will ensure that the examination method is demonstrated to be capable of detecting relevant primary water stress corrosion cracking indications.

Entergy's Response Per NB-5000 of the 1992 Edition of ASME Section III, the Liquid Penetrant process will be performed in accordance with ASME Section V, Article 6. The procedures to be used to examine Nozzle #46 meet these requirements. Additionally, the examination technique to be used has been demonstrated by past performance that it is effective in the detection of Primary Water Stress Corrosion Cracking (PWSCC) flaws in actual implementation. Extended penetrant dwell times are used and observing the development at the initial application of the PT developer and again at the procedure required final development time are practices used to enhance the process.

b. Confirm, specifically in the proposed alternative paragraph in Section 5 of the submittal, that the acceptance criterion for the PT will be PT White (i.e., no indications (linear or rounded) are allowed of any size). The NRC staff has determined that the acceptance criteria of NB-5352 in accordance with NB-5000 of the 1992 Edition of Section III for PT is not sufficient for this purpose.

2CAN102103 Enclosure Page 4 of 10 Entergy's Response The acceptance criteria for the Liquid Penetrant examination of the grind out repair is no indications (linear or rounded) of any size are allowed (i.e., PT White). It is understood that the acceptance criteria contained in ASME Section III, NB-5352 is not sufficient for this purpose. Work instructions generated for the grind out repair will specify the acceptance criteria as being PT White, which meets and exceeds the criteria contained in ASME Section III, NB-5000.

In Section 5, Part 3 Other Considerations and Section 5, Conclusions, Entergy provided the following statement:

After the final PT of the excavation, emery cloth buffing will be performed to the ground surface to aid in the removal of possible cold working. After emery cloth buffing an ultrasonic examination of the excavated area is required to demonstrate the flaw indication has been removed.

Entergy is providing this clarifying information to identify the specific sequence of events related to the informational use PT at the completion of grinding, emery cloth buffing, and final acceptance PT.

1. Defect removal will be performed using mechanical metal removal processes (i.e.,

grinding/hand machining).

2. At certain intervals during the grinding/hand machining operation, interim informational liquid penetrant (PT) examinations will be performed as necessary to determine whether the defect has been completely removed or additional grinding steps are required.

3. The defect will be considered removed when a final informational PT examination utilizing extended penetrant dwell time of 30 minutes complies with PT white acceptance criteria.

4. After completing the final informational PT, perform the required post-repair surface conditioning.

5. After satisfactorily completing the post-repair surface conditioning, perform the final code required PT examination for acceptance utilizing the extended dwell time of 30 minutes and PT white criteria for acceptance.

RAI-4 Primary Water Stress Corrosion Cracking (PWSCC) Concern The excavated location may create a crevice between the nozzle and J-groove weld, which may lead the excavation location to be more susceptible to the initiation of PWSCC. In addition, the surface of the nozzle and weld at the excavation location may be more susceptible to PWSCC because it is being cold worked due to grinding, although the proposed relief request does state

2CAN102103 Enclosure Page 5 of 10 that the licensee will use emery cloth buffing to remove cold working. Provide an evaluation of a potential crevice and/or cold working with regard to its effect on PWSSC and the structural integrity of Nozzle #46 and the adjacent J-groove weld during the next cycle of operation.

Entergy's Response The excavation process under the proposed alternative will result in an improved condition that is more resistant to PWSCC degradation. Therefore, the potential for PWSCC to affect the leak tightness or structural integrity of Nozzle #46 and the adjacent J-groove weld during future operation is reduced under the proposed alternative. The basis for this conclusion is as follows:

Material previously exposed to the primary environment is removed. Therefore, the clock is reset to time zero for the excavated area with regard to the aging degradation process of PWSCC initiation. ANO-2 began commercial operation in March 1980, so the excavation will effectively reduce the exposure time available to produce incipient PWSCC degradation by more than 40 calendar years. This is a large benefit for reducing the potential for future initiation of growing macroscopic cracks.

The excavation will be performed in a controlled manner that produces a final surface with improved surface condition compared to the typical ground condition of J-groove welds resulting from head fabrication. Skilled grinders will smooth and blend the grind area.

Emery cloth will then be manually applied to the excavated surfaces as well as any strike marks or scribe areas used for layout. The buffing will result in a polished surface that eliminates scratches that could promote PWSCC initiation. The buffing will also reduce the possibility of an aggressive surface cold-worked layer with high tensile residual stresses that could promote PWSCC. PT White will be required to accept the final surface for service, confirming the quality of the new surface to be exposed to primary coolant. References 2 through 4 describe how abusively ground surfaces may act to promote PWSCC initiation.

The process under the proposed alternative will ensure an improved surface condition that addresses this common susceptibility factor known to promote PWSCC degradation of Pressurized Water Reactor (PWR) components fabricated with Alloys 600, 82, and 182.

The excavated area under the proposed alternative is an open notch configuration that is continuously refreshed with primary coolant. The geometry will not act as a crevice that restricts mass transfer between the surface and bulk coolant. Furthermore, even if the excavation acted a restricted crevice geometry, that would not significantly increase the susceptibility to stress corrosion cracking as the PWR primary environment is deaerated except for limited time at the start of each fuel cycle. Crevice geometries are a concern for stress corrosion cracking susceptibility in aerated environments (e.g., Reference 5) such as some Boiling Water Reactor environments, not for components exposed to normal PWR reactor coolant.

The planned excavation feature under the proposed alternative is located at the weld and in the nozzle inboard (below) of the pressure boundary. The periodic direct visual examinations (VEs) and periodic volumetric or surface leak path examinations for evidence of leakage maintain defense-in-depth in the unlikely case PWSCC were to initiate at the new

2CAN102103 Enclosure Page 6 of 10 surface and grow to cause leakage. Any circumferentially oriented PWSCC originating at the excavation feature would not be at an elevation that would be a potential concern for nozzle ejection.

As described in the response to RAI 7, no PWSCC indications have been detected affecting the excavated areas previously made to remove indications affecting the ANO-2 RVCH.

RAI-5 Peening The NRC staff understands that during the current outage, the licensee is peening the inner surface of the reactor vessel closure head penetration nozzles. The relief request describes the use of emery cloth buffing after grinding. However, peening is effective in addressing PWSCC initiation. Provide justification for not applying peening to the outside diameter and wetted weld surface of penetration Nozzle #46 after grinding is complete.

Entergy's Response The equipment required for peening of the outer surfaces of the CEDM penetrations is still in development and not yet available to be applied. Therefore, peening is not an available option for conditioning of the excavated area under the proposed alternative. As described in the response to RAI 4, the planned approach, including emery cloth buffing after grinding and removal of material previously exposed to the primary water environment, will result in an improved surface condition that reduces the potential for PWSCC initiation in comparison to that for the previous surface.

RAI-6 Enhanced Leakage Detection During Operating Cycle The licensees submittal does not discuss leakage detection during normal operation, which would provide a defense-in-depth measure to address any possible indications missed by NDE or the initiation of new flaws in the potentially more susceptible ground area. Describe any defense-in-depth measures, such as enhanced leakage detection guidance, that the licensee has implemented that addresses changes in leakage as little as 0.1 gallons per minute (gpm) during the next cycle of operation.

Entergy's Response A leak or increase in radiation levels within Containment would be collected in the Containment Sump and detected by the Radiation Monitoring System during plant operation should a substantial leak develop. If an unidentified Reactor Coolant System (RCS) leak were to occur greater than 1 gpm, ANO-2's Technical Specification (TS) 3.4.6.2, "Reactor Coolant System Operational Leakage," outlines the timely actions required to maintain safe plant operation and/or requires plant shutdown. The TS required RCS leak detection methods ensure that leakage would not go undetected for long periods of time.

Additionally, ANO-2 implements WCAP 16465, "Pressurized Water Reactor Owner's Group Standard RCS Leakage Action Levels and Response Guidelines for Pressurized Water

2CAN102103 Enclosure Page 7 of 10 Reactors," Revision 0 guidance which provides action levels beginning at Tier One of 0.1 gpm of unidentified leakage. Depending on the leakage source identified, a reactor shutdown could be required in line with Limiting Condition of Operations (LCO) 3.4.6.2.

A through-wall leak from a reactor vessel closure head nozzle or weld would constitute pressure boundary leakage. Should any of the limitations be exceeded, the appropriate LCO condition would be entered. Under the proposed alternative, reasonable assurance of structural integrity is provided. However, should an RCS leak occur online, the ANO-2 leak detection capabilities maintain a defense-in-depth strategy to ensure continued safe operation.

RAI-7 Operating Experience with Removal of Indications via Grinding The Conclusions section of the proposed alternative discusses previous experience at ANO-2 for two locations that had indications successfully removed via grinding. Provide additional details on the repairs and operating experience of these locations during subsequent inspections. Also, include a discussion of those situations, as compared with the current request.

Entergy's Response The first location is Control Element Drive Mechanism (CEDM) Nozzle #49 that was repaired by grinding in Fall 2018 during 2R26.

Figure 1 The size and location of the flaw on CEDM #49 was similar to the current size and location of the flaw on CEDM #46, with the exception that the vertical position on the CEDM #49 nozzle was lower relative to the minimum design weld (see Figure 1 above). Excavation did not encroach on the minimum required design weld. The flaw on CEDM #49 was located at 330 degrees relative to the downhill position on the nozzle (0 degrees), while the flaw on CEDM #46 c~:on

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2CAN102103 Enclosure Page 8 of 10 is located 20 degrees relative to the downhill position on the nozzle. Both nozzles are in the same position in their respective quadrants with the same angle of incidence. Therefore, the flaws are essentially mirror images of one another (see Figure 2 below).

UT of the excavated region of the flaw removed from CEDM #49 (approximately three years ago). The ANO-2 RVCH has been inspected in each subsequent outage, including the current outage, in accordance with ASME Code Case N-729 and no relevant indications have been noted. This experience is most applicable based on the geometric and material similarities between the two locations.

Figure 2 The second location on ANO-2 RVCH occurred on Incore Instrument (ICI) nozzles #83 and #84.

A PT inspection in the Fall 2003 during 2R16 identified four linear indications on nozzle #83, and one linear and one rounded indication on the attachment weld of nozzle #84 that were removed by grinding. Excavation did not encroach on the minimum required design welds. The morphology and behavior of these indications were evaluated in a structured apparent cause evaluation and it was determined that the indications did not have the characteristics of PWSCC, but rather were weld metal entrapped slag. It was also later concluded that the surface indications on nozzle #83 were actually in weld metal and none were in the base metal.

Although this experience is on nozzles of a different type in the ANO-2 closure head and the indications were concluded not to be PWSCC, the experience identifies a repair by grinding on 0*'0 0 "'-0

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• 2CAN102103 Enclosure Page 9 of 10 weld metal susceptible to PWSCC approximately 18 years ago. No additional flaws have been identified on these ICI nozzles.

RAI-8 Clarifying Dates Section 6 of the proposed relief request states that...This proposed alternative is requested for one operating cycle... Identify the operating cycle and approximate end date of the operating cycle. Also provide the start and end dates for the current 5th ten-year inservice inspection interval.

Entergy's Response The upcoming operating cycle is currently scheduled to start in in the fourth quarter of 2021, coincident with startup from the current refueling outage. The operating cycle is currently scheduled to be complete in the second quarter of 2023. Specific dates are not provided due business concerns.

The 5th 10-year inservice inspection interval started on March 26, 2020 and is scheduled to end on March 25, 2030.

RAI-9 Clarifying 10 CFR 50.55a(g)(6)(ii)(D) Applicability Section 2 of the proposed relief request states that the examination category for Nozzle #46 is ASME Code Case N-729-6. However, ASME Code Case N-729-6 is conditioned by 10 CFR 50.55a(g)(6)(ii)(D). State/confirm that all of the conditions in 10 CFR 50.55a(g)(6)(ii)(D) will be satisfied.

Entergy's Response It is understood that ASME Code Case N-729-6 has conditions identified in 10 CFR 50.55a(g)(6)(ii)(D). Those conditions will be satisfied in the examination process.

References

1. Entergy Operations, Inc. (Entergy) letter to the U. S. Nuclear Regulatory Commission (NRC), " Relief Request ANO2-R&R-012 - Support the Repair of the Reactor Vessel Closure Head Penetration #46," (2CAN102102), ML21283A001, dated October 10, 2021.

2. Program on Technology Innovation: Proceedings - 2007 AECL/COG/EPRI Workshop on Cold Work in Iron-and Nickel-Base Alloys Exposed to High Temperature Water Environments. EPRI, Palo Alto, CA: 2008. 1016519. [publicly available from EPRI]

2CAN102103 Enclosure Page 10 of 10

3. Proceedings: Workshop on Detection, Avoidance, Mechanisms, Modeling, and Prediction of Stress Corrosion Cracking Initiation in Water-Cooled Nuclear Plants. EPRI, Palo Alto, CA: 2009. 1018908. [publicly available from EPRI]

4. P. Scott, et al., Comparison of Laboratory and Field Experience of PWSCC in Alloy 182 Weld Metal, Proceedings of the 13th International Conference on Environmental Degradation of Materials in Nuclear Power Systems, paper 25, CNS, 2007.

5. Corrosion Causes and Control: Part 1 Fundamentals of Corrosion. Carpenter Technology. Reprinted from Chemical Engineering Magazine, McGraw-Hill, 1972.

Attachment 2CAN102103 Draft Special Implementation Instructions (3 Pages)

DRAFT Design Olange Padage Document Number.

0000091236 D) Special lmplement.mon lnstruc:tions Special l~

lementation lnstructio:ns/Sll:etches:

I Revision:

I Applicable Facilities and Units:

000 Arkansas Nuclear One Uni:t(s) 2 The material removal allowed by this EC shall be performed using sharp (like new tooling lbits) as follows:

l _ Perform an inf ormation PT to locate and identify the area,. {indication of PTI from wflere ma.terial will be removed at the approximate 20* azimuthal location_ This PT does not need perfonmed by certified PT examiners since the only purpose is to aid in finding the indication location and removing the indication_ It is recommended to use a method to locate a datum 1point for ref erencing the grind geometry rrom this datum throughout the process_ Gage 1 noted below is one suggestion to use t o create and measure rrom a datum_ During the moclru:p, it was noted that the PT process (solvents) should be considered in the marking method so that the reference can be restored or maintained until the work is comp!ete including any iterative grinding requ ired_

2. Grinding up into the weld fillet cap is limited to a target he~ht of 0_12" beyond the end of the indkated fliaw and,0_25.. above the datum to prevent impingjng upon the pressure boundary and partial penetration weld depth_ Reference Figure 5 of LTR-SDA-21--074 attached in p2e 5 _001_ The depth of grinding into the CEDM nozzte wall radially is limited to 0-35".. The width of t he material,removed is limited to 20degrees of the nozzle diameter or-0.7" with a target to be < o_s* in width.

3. After the material is excavated - or the indication is removed, al l sharp edges of the ground area shaU be removed and blended smooth into the surrounding areas_

4 _ Once the above material is removed-or the indication is removed as indicated by iterative informational (non-certified) PTs, pre.paration for the final (certified) PT ensure the ground area is surface finished with emery cloth for t he fUII excavated area and any inadvertent tool strikes_ Emery doth surtace conditioning is an ex:pticit part of the re[ief request basis_ PT examination of the final excavated area shall be performed by a certified PT examiner_ The acceptance criteria, for the PT examination is PTwflite, all indications shall be removed to accomplish an acceptable examination.

5. Record any detected indications in the final PT and forward to Eingineering for evaluation.

6. Photographs of the PT white condition must be obtained to be presented to the NRC per RAI 2_b of AN02-RR~l2_

7. Photographs from multiple angjes with a reference scale (when posssible) will need obtained Collect reference dimensions inctuding beginning distance f rom datum, overall length, depth and width whith are needed to 1perform analysis post outage.. Multiple locations of depth a.nd width may be need based on the final geometty _ Ensure a step for engjneering to review the dimeraions for adequ.icy is provided before WO closeout.. These photos and dimensions are also to be presented to t he NRC per RAI 2.b ol AN02-RR~12-The intent of obtaining reasonable characterization of the as left condition is to limit the amount of conservative estimates the final detailed model w ill have to consider_

SmfJdarrll>RJjgn PrDClllS fP-EN6--001. Fonn 4 R,..,;,;,,_,,z Pai;.,, laf :I

DRAFT Document Number:

00ll0091236 Desii:,i O,ange Package Revision:

Applicable Facirllies iJfld Units;:

000 Arkansas Nude,ar One Unit(s) 2 8_ The WO will need routed through the ISi program and R&R engineers once planned so that sufficient inspection p@ctices and hold points can be incorporated. f rom ISi, the WO will perform the same exams that identified the flaw ie. UT (ultrasonic testing). This requirement comes from Code Case N-729-6, 3132.2 and ASME Section XI,. IWA-4422.2.1.

9_ Special gage tooling (not ed below in additional considerations) may be desirable to reduce dose. Ensure th.e gages are checked as produced against MT&E such that the intended dimensiona I checks with the custom ~ge(s) is verified prior t o use and acceptably achieved. Consider using the existing mode up in the ANO weld sho.p fo.r gnnd mock up to test viability and accuracy prior t o field use.

Additional considerations:

Engineering can be contacted for computer files for various ga 1.1ges necessary to save dose and locate and aid in dimensioning the exc,ivation area. Typical gage tooling shown below,. if desired,.

Gage Style 1 Gin be used to locate a reference point (corner) by tracing onto the nozzle the outer edges ofthe tool (nearthe number 1 mark.ed below),. Then using t hat marked corner, similar tools with varying leg lengths from the comer geometry to the beveled point can be produced. That willl allow that the distance from the created datum I marked comer) a tong the nozzle (distance into the wel.d) to be readily assessed.

Gage Styte 2 Gin be used to check (referencing the nominal 4.05" nozzle OD) the depth of the nozzle wall removed with various t ools with different projection lengths for the projecting central tab.

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Gage 1 - Linear distance tool Stzmdard Design Proa,ss IP-B:i6-0D1. Fom, 4 R,.,,;.;.,n z Pai;,,, 2oU

DRAFT Document Number.

0000091236 Gage 2 Smndard Dugi, Prooan IJl.tJi6-0DL f om, 4 R"llllion 1.

Oesic,i O,ange P:adrage I

Revision:

I Applicable Facinties and Units:

000 Arkansas Nudear One Unit(s) 2 58 -

DRAFT 38 I

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