L-MT-10-034, Relief Request from Certain Examination Coverage Requirements Imposed by the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Xl, Rules for Inservice Inspection of Nuclear Power Plant Components.

Relief Request from Certain Examination Coverage Requirements Imposed by the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Xl, Rules for Inservice Inspection of Nuclear Power Plant Components.

ML101300050
Person / Time
Site:	Monticello
Issue date:	05/06/2010
From:	O'Connor T Northern States Power Co, Xcel Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-MT-10-034
Download: ML101300050 (30)

Text

U XcelEnergy@ Monticello Nuclear Generating Plant 2807 W County Road 75 Monticello, MN 55362 May 6, 2010 L-MT-10-034 10 CFR 50.55a(g)(5)(iii)

U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Monticello Nuclear Generating Plant Docket 50-263 Renewed Facility Operating License No. DPR-22

Subject:

10 CFR 50.55a Request No. 19: Relief from Impractical Examination Coveragqe Requirements Pursuant to 10 CFR 50.55a(g)(5)(iii) for the Fourth Ten-Year Inservice Inspection Interval Pursuant to 10 CFR 50.55a, "Codes and standards," paragraph (g)(5)(iii), Northern States Power Company - Minnesota (NSPM) requests relief from certain examination coverage requirements imposed by the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Xl, "Rules for Inservice Inspection of Nuclear Power Plant Components," for the Monticello Nuclear Generating Plant (MNGP).

This 10 CFR 50.55a request is for weld examinations, performed during the 2009 refueling outage, where the required coverage of "essentially 100 percent" could not be obtained when examined to the extent practical. The basis for the 10 CFR 50.55a request is that compliance with the specified requirements is impractical due to plant design. The details of the 10 CFR 50.55a request are provided herein.

MNGP is submitting this request for the Fourth Ten-Year Inservice Inspection Interval scheduled to end on May 31, 2012.

If you have any questions or require additional information, please contact Mr. Randy Rippy at 612-330-6911.

4C4_7

Document Control Desk L-MT-1 0-034 Page 2 of 2 Summary of Commitments This lette contains no ne commitments and makes no revisions to existing commi ents.

Tnnor ite Vice esident, Monticello Nuclear Generating Plant Northern tates Power Company - Minnesota Enclosures (4) cc: Administrator, Region III, USNRC Project Manager, Monticello, USNRC Resident Inspector, Monticello, USNRC Minnesota Department of Commerce

L-MT-1 0-034 Page 1 of 10 10 CFR 50.55a REQUEST NO. 19 IN ACCORDANCE WITH 10 CFR 50.55a(g)(5)(iii)

INSERVICE INSPECTION IMPRACTICALITY

1. ASME Code Component(s) Affected Components affected are American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code), Section Xl, Class 1, Reactor Vessel Nozzle-to-Vessel welds specified below and in-detail in Table A of Enclosure 2:

Recirculation Inlet Nozzle N-2A Weld - N-2A NV Main Steam Outlet Nozzle N-3C Weld - N-3C NV Feedwater Inlet Nozzle N-4B Weld - N-4B NV Reactor Head Spare Nozzle N-6B Weld - N-6B NV Reactor Head Vent Nozzle N-7 Weld - N-7 NV Jet Pump Instrumentation Nozzle N-8B Weld - N-8B NV Standby Liquid Control Inlet/ Nozzle N-10 Weld - N-10 NV Core Differential Pressure

2. Applicable ASME Section XI Code Edition and Addenda The applicable ASME Section Xl Code for the Monticello Nuclear Generating Plant (MNGP), Fourth Ten-Year Inservice Inspection (ISI) Interval is the 1995 Edition with the 1996 Addenda. ASME Section Xl, Appendix VIII requirements are implemented as required by, and as modified by, 10 CFR 50.55a. Procedures and personnel are qualified to the Performance Demonstration Initiative (PDI). The PDI Program document meets the requirements of 10 CFR 50.55a up through the 2001 Edition of Section Xl.

3. Applicable Code Requirement m m m ASME Class 1 Nozzle-to-Vessel welds are subject to the examination requirements of Subsection IWB Table IWB-2500-1, as shown below, and 10 CFR 50.55a(b)(2)(xv)(G). The welds are required to be examined once within the Fourth Ten-Year Interval:

Code Class: 1

References:

IWB-2500, Table IWB-2500-1 Examination Category: B-D Item Number: B3.90

Description:

Nozzle-to-Vessel Welds Component Numbers: See Section 1 and Enclosure 2 Table A System: Reactor Vessel Examination Method: Volumetric - Ultrasonic Testing (UT)

Examination Volume: Figure IWB-2500-7(b)

L-MT-10-034 Page 2 of 10 10 CFR 50.55a REQUEST NO. 19 IN ACCORDANCE WITH 10 CFR 50.55a(g)(5)(iii)

INSERVICE INSPECTION IMPRACTICALITY In October 2007, the Nuclear Regulatory Commission (NRC) issued Regulatory Guide (RG) 1.147, Revision 15, "Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1" (Reference 1). In RG 1.147, the NRC identifies the ASME Code Cases they have determined to be acceptable alternatives to applicable parts of Section XI, and indicate that licensees may use these Code Cases without requesting authorization from the NRC, provided that they are used with any identified limitations or modifications. RG 1.147, Table 1 lists the following two Code Cases as acceptable to the NRC for use by a licensee with no identified limitations or modifications:

1) Code Case N-460 (Reference 2),

2) Code Case N-613-1 (Reference 3).

Code Case N-460 states in part, "when the entire examination volume or area cannot be examined due to interference by another component or part geometry, a reduction in examination coverage on any Class 1 or Class 2 weld may be accepted provided the reduction in coverage for that weld is less than 10 percent."

NRC Information Notice (IN) 98-42 (Reference 4) termed a reduction in coverage of less than 10 percent to be "essentially 100 percent." IN 98-42 states in part, "The NRC has adopted and further refined the definition of 'essentially 100 percent' to mean 'greater than 90 percent'...has been applied to all examinations of welds or other areas required by ASME Section XI."

As an alternative to Figure IWB-2500-7(b), Code Case N-613-1 requires an examination volume that includes the width of the weld plus one-half inch of adjacent base metal on each side of the widest part of the weld. In comparison, the examination volume required by the Figure IWB-2500-7(b) includes the width of the weld plus the adjacent base metal on each side of the widest part of the weld equal to one-half of the vessel shell wall thickness.

4. Impracticality of Compliance Construction Permit CPPR-31 was obtained for the MNGP in 1967. The MNGP systems and components were designed and fabricated before the examination requirements of ASME Section Xl were formalized and published. Therefore, MNGP was not specifically designed to meet the requirements of ASME Section XI and full compliance is not feasible or practical within the limits of the current plant design.

10 CFR 50.55a recognizes the limitations to inservice inspection of components in accordance with Section XI of the ASME Code imposed due to early plants' design and construction, as follows:

L-MT-1 0-034 Page 3 of 10 10 CFR 50.55a REQUEST NO. 19 IN ACCORDANCE WITH 10 CFR 50.55a(g)(5)(iii)

INSERVICE INSPECTION IMPRACTICALITY 10 CFR 50.55a(g)(1): For a boiling or pressurized water-cooled nuclear power facility whose construction permit was issued prior to January 1, 1971, components (including supports) must meet the requirements of paragraphs (g)(4) and (5) of this section to the extent practical.

10 CFR 50.55a(g)(4): Throughout the service life of a boiling or pressurized water-cooled nuclear power facility, components (including supports) which are classified as ASME Code Class 1, Class 2, and Class 3 must meet the requirements, except design and access provisions and pre-service examination requirements, set forth in Section XI of editions of the ASME Boiler and Pressure Vessel Code ... to the extent practical within the limitations of design, geometry and materials of construction of the components.

10 CFR 50.55a(g)(5)(iii): If the licensee has determined that conformance with certain code requirements is impractical for its facility, the licensee shall notify the Commission and submit, as specified in § 50.4, information to-support the determinations.

The inspection limitations on the subject components are due to inherent nozzle design geometric contours and interference (see Enclosure 2 Table A).

A description of the examination methodology used to provide the maximum obtainable coverage is provided in Section 6 of this request. This methodology is based on ASME Section Xl, Appendix VIII qualification and was applied to the extent practical within the design constraints of the components. Enclosure 3 provides cross-sectional diagrams of the subject welds showing the geometric contour of the component design in relation to the welds and the coverage obtained within the alternative examination volume requirements of Code Case N-613-1, Figure 2.

5. Burden Caused by Compliance Compliance with the examination coverage requirements of ASME Section XI would require modification, redesign, or replacement of components where geometry is inherent to the component design.

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INSERVICE INSPECTION IMPRACTICALITY

6. Proposed Alternative and Basis for Use Proposed Alternative In accordance with 10 CFR 50.55a(g)(5)(iii), relief is requested for the components listed in Table A of Enclosure 2 on the basis that the required examination coverage of "essentially 100 percent" is impractical due to physical obstructions and the limitations imposed by design, geometry and materials of construction.

Northern States Power Company - Minnesota (NSPM) performed qualified volumetric examinations that achieved the maximum, practical amount of coverage obtainable within the limitations imposed by the design of the components. In addition to volumetric examinations, as Class 1 Examination Category B-P components, a VT-2 examination is performed on the subject components of the Reactor Coolant Pressure Boundary (RCPB) during system pressure tests each refueling outage. This was completed during the 2009 refueling outage and no evidence of leakage was identified for these components.

Pursuant to 10 CFR 50.55a(g)(5)(iii), NSPM requests authorization of an alternative to the requirements of ASME Section Xl Table IWB-2500-1, Category B-D, Item B3.90, and proposes to utilize these completed exams as acceptable alternatives that provide reasonable assurance of continued structural integrity.

Basis for Use The NSPM Nondestructive Examination (NDE) procedures incorporate inspection techniques qualified under Appendix VIII of the ASME Section Xl Code by the PDI for examination of the subject nozzle-to-vessel welds, and allow the examination volume to meet the provisions of alternative requirements (i.e., Code Case N-613-1).

The examinations were performed from the Reactor Vessel exterior surface using a manual contact method from the nozzle blend radius, the nozzle-to-vessel shell weld, and vessel shell surface. Coverage was obtained by following the scan parameters designated within NSPM NDE procedures for each nozzle configuration and angle, including those parameters defined by MNGP specific Electric Power Research Institute (EPRI) computer modeling reports (References 5 and 6). It should be noted that that the scans defined by the EPRI report are only applicable to the inner 15 percent of the weld volume when scanning in the parallel (circumferential) direction.

The refracted longitudinal wave mode of propagation was applied for all radial (axial) scans of the exam volume. The refracted longitudinal wave mode of propagation was also applied to the outer 85 percent of the exam volume for parallel scans. As required by the NSPM NDE procedures and the EPRI computer modeling report, the

L-MT-1 0-034 Page 5 of 10 10 CFR 50.55a REQUEST NO. 19 IN ACCORDANCE WITH 10 CFR 50.55a(g)(5)(iii)

INSERVICE INSPECTION IMPRACTICALITY shear wave mode of propagation was applied for each of the transducer and wedge combinations required for the remaining inner 15 percent of the parallel scan exam volume.

The subject components received the required examination(s) to the extent practical within the limited access of the component design. One hundred percent coverage was obtained for the inner 15 percent of the examination volume for the radial and parallel scans. The examination limitations for the subject components were encountered within the outer 85 percent of the examination volume for the parallel and radial scans. For the examinations conducted, satisfactory results were achieved, and no evidence of unacceptable flaws was detected with the inspection techniques.

Due to the design of these welds it was not feasible to effectively perform a volumetric examination of "essentially 100 percent" of the required volume. The nozzle-to-vessel welds are accessible from the vessel plate side of the weld and are examined to the extent practical with qualified techniques, but the curvature of the nozzle forging and proximity to the weld precludes obtaining further coverage of the excluded areas within the outer 85 percent of the examination volume.

As required by site procedure, when limitations are encountered that prevent obtaining full coverage of a required volume while performing ISI examinations, the limitations are required to be quantified and recorded.

The method used to determine coverage is based on field measurements applied to a two dimensional plot. This allows an informed approximation to be made of the coverage achieved. The methodology is appropriate to the application in that the limitations are physical and the methods applied to the examination are established by the qualified techniques. Variations in the percent coverage obtained from the previous examinations are the result of changes in examination technique and/or required coverage. The current coverage determinations are different from past examinations due to the use of PDI qualified techniques and a reduced exam volume required by use of Code Case N-613-1.

Per 10 CFR 50.55a(g)(1) and (4), each of the subject welds 1 were examined to the extent practical during the First, Second, and Third Ten-Year ISI Intervals. Prior to 1997, NSPM did not perform examination coverage determinations or submit relief requests pursuant to 10 CFR 50.55a for limited examinations due to a misinterpretation of 10 CFR 50.55a(g)(4). It was construed that the interferences inherent in the design constituted impracticality and were exempted.

As an exception, the N-10 weld was not examined in the First Interval based on approved ISI Relief Request #15 (Reference 14)

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INSERVICE INSPECTION IMPRACTICALITY This misinterpretation was identified during the Third Ten-Year ISI Interval and was reported to the NRC in Licensee Event Report (LER)97-004 (Reference 13).

Going forward from 1998, relief requests for limited exams have been submitted to the NRC. There is no means for retroactively complying with 10 CFR 50.55a for prior Intervals. These issues were documented in the MNGP corrective action program and various corrective actions were taken to prevent recurrence, including submittal of relief requests after completion of every refueling outage when examination coverage is limited and Code examination requirements cannot be met.

Details regarding the aforementioned limited exam relief request issues were included with supplemental information submitted to the NRC in March 2008. The supplemental information was provided to assist the NRC with review of MNGP 4th Interval Relief Request #15 (Reference 19) which was subsequently approved in May 2008 (Reference 9).

The coverage drawings in Enclosure 3 give a representation of the examination volume and the weld interface line in the same manner as the figure included in Code Case N-613-1. The areas of examination volume coverage are identified by the lightly shaded or cross-hatched areas on the drawings. The remaining areas of the examination volume, with black shading or with no shading or no cross-hatching, represent areas with no coverage. On page 16 of Enclosure 3, a sketch of a typical nozzle is provided with a cross sectional view of the weldment depicting the curvature of the nozzle exterior surface and its effect on transducer liftoff. Although there is some variation, most of the limited coverage is in the nozzle base material with a lesser amount in the weld and base material on the vessel shell side.

Additional coverage for the limited areas was not achievable or practical, based on the latest qualified ultrasonic technology, nor by other considered examination methods, such as radiography. NSPM has concluded that if significant degradation existed in the subject welds, it would have been identified by the examinations performed.

A table of examination history and results is provided for prior ISI Intervals in Enclosure 4, including available coverage information and Relief Requests.

Additionally, as Class 1 Examination Category B-P components, VT-2 examinations were performed on the subject components in association with the RCPB system pressure test performed during the 2009 refueling outage. No evidence of leakage was identified during this system test.

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INSERVICE INSPECTION IMPRACTICALITY The materials for the subject components are A508 CI II nozzle forgings welded to A533 Cl I vessel shell plate. The weld filler material for the subject joints was E8018NM. Inner diameter cladding materials are E309-15 for the base layer, and ER308L or E308L-1 5 for subsequent layers. A review of operating experience within the nuclear industry did not reveal any instances of cracking in this location and type of weldment, specifically nozzle-to-vessel shell welds.

The MNGP reactor vessel water chemistry is controlled in accordance with the 2008 revision to the BWR Water Chemistry Guidelines (Reference 7). Also a hydrogen water chemistry system is used to reduce the oxidizing environment in the reactor coolant. These additional measures provide added assurance against the initiation of cracking or corrosion from the inside surface of the reactor vessel. An inerted primary containment environment during operation provides assurance of corrosion protection on the outside surface of the reactor vessel.

The provisions described above, as an alternative to the code requirement, will continue to provide reasonable assurance of the structural integrity of the subject welds. The examinations were completed to the extent practical and no unacceptable flaws were identified. VT-2 examinations performed on the subject components during system pressure testing each refueling outage (in accordance with Examination Category B-P) provide continued assurance that the structural integrity of the subject components is maintained. Additionally, the MNGP Water Chemistry Program and inerted primary containment environment provide added measures of protection for the component materials.

Therefore, pursuant to 10 CFR 50.55a(g)(5)(iii), NSPM requests that the NRC grant relief from the ASME Section Xl examination requirements for the subject nozzle-to-vessel welds.

7. Duration of Proposed Alternative NSPM requests the granting of this relief for the Fourth Ten-Year Inservice Inspection Interval of the Inservice Inspection Program for the MNGP that is scheduled to end on May 31, 2012.

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INSERVICE INSPECTION IMPRACTICALITY

8. Precedent The NRC has granted relief for other nozzle-to-vessel shell welds at the MNGP, most recently for the current Fourth Ten-Year Inservice Inspection Interval (References 8 and 9). Also, the NRC has granted relief for the Quad Cities Nuclear Power Station, Units 1 and 2 (Reference 10), Dresden Nuclear Power Station, Units 2 and 3 (Reference 11), and Prairie Island Nuclear Generating Plant, Unit 2 (Reference 12).

L-MT-10-034 Page 9 of 10 10 CFR 50.55a REQUEST NO. 19 IN ACCORDANCE WITH 10 CFR 50.55a(g)(5)(iii)

INSERVICE INSPECTION IMPRACTICALITY REFERENCES

1. Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability, ASME Section Xl, Division 1," Revision 15, October 2007.

2. ASME Section Xl Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds."

3. ASME Section Xl Code Case N-613-1, "Ultrasonic Examination of Full Penetration Nozzles in Vessels, Examination Category B-D, Item No's. B3.10 and B3.90, Reactor Nozzle-To-Vessel Welds, Figures IWB-2500-7(a), (b), and (c)."

4. NRC Information Notice 98-42, "Implementation of 10 CFR 50.55a(g) In-service Inspection Requirements."

5. EPRI Internal Report IR-2004-63, "Monticello Nozzle Inner Radius and Nozzle-to-Shell Weld Examinations," dated December 2004.

6. EPRI Internal Report IR-2006-100, "Monticello Nozzle Inner Corner Regions and Nozzle-to-Shell Weld Examinations," dated January 2006.

7. "BWRVIP-1 90: BWR Vessel and Internals Project, BWR Water Chemistry Guidelines -

2008 Revision," EPRI Technical Report, TR-1016579, October 2008.

8. NRC letter to NMC, "Monticello Nuclear Generating Plant (MNGP) - Fourth 10-Year Interval Inservice Inspection (ISI) Program Plan Relief Request No. 13 (TAC No.

MC8882)," dated July 18, 2006.

9. NRC letter to NMC, "Monticello Nuclear Generating Plant (MNGP) - Granting of Relief Regarding Limited Ultrasonic Examination Coverage of Five Welds (TAC No.

MD6854)," dated May 19, 2008.

10. Letter from NRC to Exelon Generation Company, LLC, "Quad Cities, Units 1 and 2 -

Relief Request CR-39 for Third 10-Year Inservice Inspection Interval (TAC Nos.

MC2427 and MC2428)," dated May 10, 2005.

11. Letter from NRC to Exelon Generation Company, LLC, "Dresden Nuclear Power Station, Units 2 and 3 - Relief Request CR-26 For Third 10-Year Inservice Inspection Interval (TAC Nos. MC3269 and MC3270)," dated October 1, 2004.

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INSERVICE INSPECTION IMPRACTICALITY

12. NRC letter to NMC, "Prairie Island Nuclear Generating Plant, Unit 2 - Evaluation of Relief Request No. 16 for the Unit 2 3rd 10-year Interval Inservice Inspection Program (TAC No. MC1775)," dated October 18, 2004.

13. LER 97-004, "Failure to Submit Relief Requests for Limited Inservice Inspection Examinations," dated March 24, 1997.

14. NRC letter to Northern States Power Company, "Safety Evaluation Report, Monticello Nuclear Generating Plant Inservice Inspection Program," dated April 10, 1981.

15. MNGP Corrective Action Program Action Request (CAP A/R) 01126631, "Available documentation doesnt [sic] support closed M97024A action", origination date February 8, 2008.

16. MNGP Letter to NRC, "Request for Relief No. 11 for the 3rd 10-Year Interval Inservice Inspection Program," dated May 25, 2000.

17. MNGP Letter to NRC, "Supplemental Information Request for Relief No. 11 for the 3rd 10-Year Interval Inservice Inspection. Program," dated July 11, 2000.

18. MNGP Corrective Action Program Action Request (CAP A/R) 01013875, "6 limited ISI exams not included in Cycle 19 Relief Request", origination date February 7, 2006.

19. MNGP Letter to NRC, "Response to Request for Additional Information Regarding 10 CFR 50.55a Request No. 15 (RR-15): Relief from Impractical Examination Coverage Requirements Pursuant to 10 CFR 50.55a(g)(5)(iii) for the Fourth Ten-Year Inservice Inspection Interval (TAC No. MD6854)," dated March 21, 2008.

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INSERVICE INSPECTION IMPRACTICALITY TABLE A - Category B-D, "Full Penetration Welds of Nozzles in Vessels," Item No. B3.90 2009 Refueling Outage, Percent Coverage and Limitations for Nozzles N-2A, N-3C, N-4B, N-6B, N-7, N-8B, and N-10 Code Code Component Category System and Percent2 Exam and and Component ID1 Examination Volume Coverage Report Item No. Component Description Required Obtained Limitations Number Reactor Vessel, Nozzle-to-Vessel Weld, Limited due to B-D Recirculation Inlet N-2A NV Code Case N-613-1 83% nozzle configuration. 2009UT033 B3.90 Nozzle N-2A Figure 2 Reactor Vessel, Nozzle-to-Vessel Weld, Limited due to B-D Main Steam Outlet N-3C NV3 Code Case N-613-1 83% nozzle configuration.

B3.90 Nozzle N-3C Figure 2 Reactor Vessel, Nozzle-to-Vessel Weld, Limited due to B-D Feedwater Inlet N-4B NV Code Case N-613-1 83% nozzle configuration. 2009UT026 B3.90 Nozzle N-4B Figure 2 Reactor Vessel, Nozzle-to-Vessel Weld, Limited due to B-D Top Head Spare N-6B NV Code Case N-613-1 87% nozzle configuration. 2009UT021 B3.90 Nozzle N-6B Figure 2 Reactor Vessel, Nozzle-to-Vessel Weld, Limited due to B-D Top Head Vent N-7 NV Code Case N-613-1 87% nozzle configuration. 2009UT023 B3.90 Nozzle N-7 Figure 2 Reactor Vessel, Nozzle-to-Vessel Weld, Limited due to B-D Jet Pump Instrumentation N-8B NV Code Case N-613-1 83% nozzle configuration. 2009UT028 B3.90 Nozzle N-8B Figure 2 Nozzle-to-Vessel Weld, Limited due to B-D Reactor Vessel, B39 Standby Liquid Inlet/ Core N-10 NV Code Case N-613-1 85% nozzle configuration 2009UT030 Diff. Pressure Nozzle N-10 Figure 2 todvesse skirtw to vessel skirt weld.

1 With exception of component N-3C NV, no indications were reported for the component's examination.

2 Due to the nozzle design it was not feasible to effectively examine essentially 100 percent of the required examination volume as defined in Figure 2 of Code Case N-613-1. Percentages are conservatively rounded down to the nearest whole number.

3 Previously observed subsurface indication was re-confirmed and re-evaluated as acceptable per Code paragraph IWB-3512-1. No observed change since previous exam in 1998.

L-MT-10-034 Page 1 of 16 10 CFR 50.55a REQUEST NO. 19 IN ACCORDANCE WITH 10 CFR 50.55a(g)(5)(iii)

INSERVICE INSPECTION IMPRACTICALITY EXAM LIMITATIONS IMPOSED BY COMPONENT DESIGN AND CONSTRUCTION This enclosure contains a series of excerpts from the ISI Ultrasonic Testing (UT) reports applicable to the subject components.

These excerpts contain sketches depicting the component configuration with physical limitations imposed by the design, e.g., geometrical contour, weld position, interferences, and a cross sectional view depicting the UT coverage and limitations in relation to the required examination volume.

Also included is a sketch of a typical reactor vessel nozzle contour and the resulting effect that causes the UT transducer to lift and lose effective coupling when it reaches the nozzle blend radius. Detail is also provided to describe the various assembly components including reference to the internal and external reactor vessel surfaces.

COMPONENT REPORT PAGE(S)

N-2A NV 2009UT033 Pages 2-3 N-3C NV 2009UT024 Pages 4-5 N-4B NV 2009UT026 Pages 6-7 N-6B NV 2009UT021 Pages 8-9 N-7 NV 2009UT023 Pages 10-11 N-8B NV 2009UT028 Pages 12-13 N-10 NV 2009UT030 Pages 14-15 Typical Reactor Vessel Nozzle contour affecting Page 16 transducer contact at blend radius

L-MT-1 0-034 Page 2 of 16 Coverage drawings excerpted from applicable reports Component N-2A NV Axial (Radial) Scan Plot Report # 2009UT033 i Supplementat Report Repori No. 2009UT03 Summary No.: 102656 Monticello N2A Coverage Plot Axial scan direction ael-A Area of covcmge 60 deg.

L-MT-1 0-034 Page 3 of 16 Component N-2A NV Parallel (Circ) Scan Plot Report # 2009UT033 SXcelEnerg Supplemental Report Report No.: 2009LI'T33 Summrwry No.: 102656 mnficello N2A Coverage Plot Parallel scan direction No Iof veiaige Inner 15% 1

L-MT-1 0-034 Page 4 of 16 Component N-3C NV Axial (Radial) Scan Plot Report # 2009UT024 91 XceIE~isrgy Supplemental Report Report No.: 2U09UT024 SuMmary No.: 102080 R3.50 Monticello N3C Coverage Plot Axial scan direction Area of coverage 60 deg.

L-MT-10-034 Page 5 of 16 Component N-3C NV Parallel (Circ) Scan Plot Report # 2009UT024 9 XceErne~i Supplemental Report Report No,: 2D09UT024 Summary No,: 102550 in

)nticello N3C Coverage Plot Parallel scan direction No w

,of Qoverage Inicr 15%,

G F E

L-MT-1 0-034 Page 6 of 16 Component N-4B NV Axial (Radial) Scan Plot Report # 2009UT026 XcelF-ergw X Supplemental Report Repoar No.: 2009UT026 Sunmary No.: 10268G Monticello N4B Coverage Plot Axial scan direction of coverage 60 deg.

L-MT-10-034 Page 7 of 16 Component N-4B NV Parallel (Circ) Scan Plot Report # 2009UT026

& XWEneW Supplemental Report Report No,: 2009UT026 Surmmery No.: 102686

)in Monticello N4B Coverage Plot Parallel scan direction No a Sof covmagre Inner 15%

G

L-MT-10-034 Page 8 of 16 Component N-6B3 NV Axial (Radial) Scan Plot Report # 2009UT021 Supplemental Report Rf n !46.:. 200BUT021 Sunmmary No.., 102377 Monticello N6B Coverage Plot Axial scan direction B C No COM

L-MT-1 0-034 Page 9 of 16 Component N-6B NV Circ (Parallel) Scan Plot Report # 2009UT021

'C? XMIErgy Supplemental Report Rep0ort ft.: 200BUT021 Summary No.: 102377 Monticello N6B Coverage Plot Circ scan direction No Covmage Am of. QcoUW

L-MT-1 0-034 Page 10 of 16 Component N-7 NV Axial (Radial) Scan Plot Report # 2009UT023 X E7erg f-? r N.! Supplemental Report Report No.: 2009UT023 Su~mmary No.- 102379 Monticello N7 Coverage Plot Axial scan direction No Covft~v B ^C AM efcbei,"

L-MT-1 0-034 Page 11 of 16 Component N-7 NV Circ (Parallel) Scan Plot Report # 2009UT023

& XmeEnergy' Supplemental Report Report NW, 2009UT023 Summary No.: 102379 Monticello N7 Coverage Plot Circ scan direction C

L-MT-1 0-034 Page 12 of 16 Component N-8B NV Axial (Radial) Scan Plot Report # 2009UT028 SXcel Ernery Supplemental Report Report No-: 2009UT028 Summary NO'1.

102689 Monticello N8BCoverage Plot

. Axial scan direction D

No Area of coverage 60 deg.

L-MT-1 0-034 Page 13 of 16 Component N-8B NV Parallel (Circ) Scan Plot Report # 2009UT028 XcelEnergy* Supplemental Report Report No.: 2009UT026 Summa~ry No.; 102598 R3.00 in Monticello N8B Coverage Plot Parallel scan direction A B C D No of coverage Inner

L-MT-1 0-034 Page 14 of 16 Component N-10 NV Axial (Radial) Scan Plot Report # 2009UT030

& XceeJavrW-' Supplemental Report Report No.: 200BUT030 Summmy No.; 102623 lii iA ;l 13 00 in S2 Monticello N- 10 Nozzle Axial Scan Coverage

L-MT-10-034 Page 15 of 16 Component N-10 NV Circ (Parallel) Scan Plot Report # 2009UT030 jq XceImner- Supplemental Report Report No.: 200RUT030 Summary No.: 102623 Monticello N410 Nozzle Cire Scan Coverage lnaer 15%

L-MT-1 0-034 Page 16 of 16 Typical Representation of Nozzle Limitations Vessel Nozzle Blend Radius Exam Volume: A-B-C-D-E-F-G-H (exterior) Weld Represented By: B-C-F-G 600 Axial scan shown Reactor Vessel Shell Scanning past this point (exterior surface) onto the nozzle blend radius causes Lift-off I loss of contact Vessel Nozzle Reactor Vessel Shell (interior surface) (interior surface) in. 1/2* i.

L-MT-10-034 Page 1 of 1 10 CFR 50.55a REQUEST NO. 19 IN ACCORDANCE WITH 10 CFR 50.55a(g)(5)(iii)

INSERVICE INSPECTION IMPRACTICALITY Table I - Historical Examination Information Interval / Exam Coverage I Results for Relief NRC Approval Weld Year Limited Exam Request N-2A 1st / 1974 (Note 1), no flaw indications (Note 2) (Note 2) 2nd I 1982 (Note 1), no flaw indications (Note 2) (Note 2) 3rd I 2001 62% coverage, no flaw 3rd, ISI RR-16 TAC No. MB5487, indications May 19, 2003 N-3C 1st / 1975 (Note 1), no flaw indications (Note 2) (Note 2) 2nd / 1989 (Note 1), no flaw indications (Note 2) (Note 2) 3rd I 1998 51% coverage, acceptable 3rd, ISI RR-10 TAC No. MB3397, mid-wall indication August 4, 1999 N-4B 1st / 1977 (Note 1), no flaw indications (Note 2) (Note 2) 2nd I 1987 (Note 1), no flaw indications (Note 2) (Note 2) 3rd I 1998 51% coverage, no flaw 3rd, ISI RR-10 TAC No. MB3397, indications August 4, 1999 N-6B 1st / 1981 (Note 1), no flaw indications (Note 2) (Note 2) 2nd I 1991 (Note 1), no flaw indications (Note 2) (Note 2) 3rd / 2000 70% coverage, no flaw (Note 3) (Note 3) indications N-7 1st /1973 (Note 1), no flaw indications (Note 2) (Note 2) 2nd I 1984 (Note 1), no flaw indications (Note 2) (Note 2) 3rd I 1998 89% coverage, no flaw 3rd, ISI RR-10 TAC No. MB3397, indications August 4, 1999 N-8B 1st I 1981 (Note 1), no flaw indications (Note 2) (Note 2) 2nd I 1991 (Note 1), no flaw indications (Note 2) (Note 2) 3rd I 2001 62% coverage, no flaw 3rd, ISI RR-16 TAC No. MB5487, indications May 19, 2003 N-10 1st I N/A N/A 1st, ISI RR-15 Safety Evaluation Report, Apr 10, 1981 2nd I 1989 (Note 1), no flaw indications (Note 2) (Note 2) 3rd I 2000 55% coverage, no flaw (Note 3) (Note 3) indications Note 1: MNGP did not document Code coverage values for limited exams prior to 1997 (References 9 and 13)

Note 2: With the exception of relief identified for the 1st Interval for Nozzle N-10 due to inaccessibility at the time (Reference 14), relief was not requested for limited exams on the subject welds prior to 1997 (Reference 9, 13, and 15)

Note 3: Limited exam errantly omitted from 3rd Interval ISI Relief Request 11 submitted for the 2000 refueling outage (References 16 and 17), as documented in the MNGP Corrective Action Program (Reference 18)