ML20198S178

SER Re Second 10-year Interval Inservice Insp Program Plan & Associated Requests for Relief for Southern Nuclear Operating Co,Inc Units 1 & 2

ML20198S178
Person / Time
Site:	Vogtle
Issue date:	12/31/1998
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20198S163	List: ML20198S160 ML20198S178 ML20198S194
References
NUDOCS 9901110196
Download: ML20198S178 (16)

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UNITED STATES g

j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 30666-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATl_QN SECOND 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN I

AND l

ASSOCIATED REQUESTS FOR RELIEF SOUTHERN NUCLEAR OPERATING COMPANY. INC.. ET AL.

VOGTLE ELECTRIC GENERATING PLANT. UNITS 1 AND 2 DOCKET NOS. 50-424 AND 50-425

1.0 INTRODUCTION

Inservice inspection (ISI) of the American Society of Mechanical Engineers (ASME) Code l

Class 1,2, and 3 components shall be performed in accordance with Title 10 of the Code of l

Federal Reaulations (10 CFR) Section 50.55a(g)(6)(i), and Section XI of the ASME Boiler and Pressure Vessel Code (ASME Code) and applicable addenda as required by 10 CFR 50.55a(g), except where specific relief has been granted by the Commission. The requirements in 10 CFR 50.55a(a)(3) state that alternatives to the requirements of i

paragraph (g) may be used, when authorized by the NRC, if (i) the proposed alternatives would provide an acceptable level of quality and safety or (ii) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1,2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, " Rules for Inservice Inspection of Nuclear Power Plant Components," to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that inservice examination of components and system pressure tests i

conducted during the first 10-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of Section XI of the ASME Code, incorporated by reference in 10 CFR 50.55a(b),12 months prior to the star'. of the 120-month interval, subject to the limitations and modifications listed therein. The applicable edition of Section XI of the ASME Code for Vogtle Electric Generating Plant, Unit 1, second 10-year ISI interval, is the 1989 Edition. Authorization to use this Code Edition for Unit 2 has been granted in this Safety Evaluation.

By letter dated May 29,1997, Southern Nuclear Operating Company, Inc. (the licensee) submitted its second 10-year interval ISI program plan and associated requests for relief (RRs) for the Vogtle Electric Generating Plant. In addition, the licensee submitted additional information on its second 10-year interval ISI program plan and associated RRs in its letter dated June 26,1998.

I 9901110196 981231 1

PDR ADOCK 05000424 8

l PDR

l 2.0 EVALUATION l

The staff, with technical assistance from its contractor, the Idaho National Engineering and Environmental Laboratory (INEEL), has evaluated the information provided by the licensee in support of its second 10-year ISI program plan and associated RRs for Vogtle Electric Generating Plant (VEGP), Units 1 and 2. Based on the results of its review, the staff does not adopt INEEL's conclusions and recommendations, with respect to RR-18, presented in the l

Technical Evaluation Report (TER), which is contained in Attachment 1. In addition, RR-29 was evaluated solely by the NRC staff.

The NRC staff determined that there are no deviations from the regulatory requirements or commitments identified in the licensee's second 10-year interval ISI program plan for VEGP Units 1 and 2.

RR-1. Subsection lWA-2413. Proposed Alternative to Successive Interval Schedulina:

Paragraph IWA-2413, " Successive inspection Intervals," of the 1989 Edition of ASME Section XI states: "The inspection plan for each successive inspection intervd shall cordply with the Edition and Addenda of this Division that has been adopted by the regulatory authority, 12 months prior to the start of the inspection interval, or subsequent Editions and Addenda that have been adopted by the regulatory authority. Specific portions or such subsequent Editions or Addenda may be used provided all related requirements are met." Pursuant to.

10 CFR 50.55a(a)(3)(i), the licensee proposed to start the VEGP-2, second 10-year interval (and subsequent intervals, for the remainder of the plant life), ahead of schedule such that the two VEGP units will be under the same edition and/or addenda of the Code, i.e., the 1989 Edition of ASME Section XI. Further, relief is requested from the requirements of 10 CFR 50.55a(g)(4)(ii) for updating the VEGP-2 ISI program at its normal update time, i.e., May 20, 1999, for its second 10-year interval. By aligning the intervals for Units 1 and 2, the licensee can perform ISI using the same Code edition for both units. Since the two units are nearly identical, this willimprove the efficiency of ISI performed at VEGP. Furthermore, since the overall number of examinations performed will not be reduced, the licensee will maintain an acceptable level of quality and safety for the plant. The staff concludes that the licensee's proposed alternative provides an acceptable level of quality and safety. Therefore, the proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).

RR-2. Examination Cateaories B-D and B-F. Items B3.90. 83.100. and B5.10. Reactor Pressure Vessel Nozzle-to Shell. Nozzle Inner Radius Sections. and Nozzle-to Safe End Examinations:

Section XI, Table IWB-2500-1, Examination Category B-D, items B3.90 and B3.100, and

~ Examination Category B-F, item B5.10, require a 100 percent volumetric examination of all reactor vessel nozzle-to-shell welds, nozzle inner radius sections, and nozzle-to-safe end butt welds each inspection interval as defined by Figures IWB-2500-7 and IWB-2500-8. At least 25 percent but not more than 50 percent (credited) of the nozzles shall be examined by the end

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of the first inspection period and the remainder by the end of the inspection interval. Reactor pressure vessel nozzle safe end welds may be performed coincident with the vessel nozzle examinatic,ns. Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee proposed to implemert Code I-

1 i Case N-521, Alternative Rules for Deferral of Inspections of Nozzle to-Vessel Welds, inside Radius Sections, and Nozzle to Safe End Welds of a Pressurized Water Reactor Vessel.

Considering that the licensee has met all the conditions stated in the Code Case and has examined all of the affected areas at the end of the previous interval, a new sequence of examinations has been established. Furthermore, since the time between examinations will not i

l exceed 10 years, the licensee's proposed alternative will provide reasonable assurance of I

structural integrity and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i). The use of Code Case N-521 is authorized for the second 10-year interval at VEGP, or until the Code Case is approved for general use by reference in Regulatory Guide 1.147. At that time, the licensee may continue to use the Code Case with the l

limitations, if any, listed in Regulatory Guide 1.147.

l RR-3. Examination Cateaorv B-A. Items B1.11. B1.12. and B1.21. Reactor Pressure Vessel (RPV) Welds:

l RR 3 was withdrawn by the licensee in its June 26,1998, submittal.

RR-4 (Part 1). Examination Cateaorv B A. Item B1.40. Reactor Pressure Vessel (RPV)

Closuro Head Welds:

Examination Category B-A, item B1.40, requires 100 pcreent volumetric and surface examination of RPV head-to-flange welds, as defined by Figure IWB-2500-5. Pursuant to l

10 CFR 50.55a(g)(5)(iii), the licensee requested relief from performing volumetric examination to the extent required by the Code for the RPV closure head to-flange welds listed in its I

l submittal. The requirements of the Code are impractical due to an integrated head package and imposition of the requirement would require design modifications that would result in a burden on the licensee. The licensee can examine a considerable portion (65 percent) of each of the subject welds, in addition, the surface examination can be completed to the extent required by the Code. The partial ultrasonic examination, in combination with the Code-required surface examination should detect any significant patterns of degradation and provide reasonable assurance of the continued structuralintegrity of the RPV closure head-to-flange weld. Based on the impracticality of meeting the Code-coverage requirements for the subject welds, and the reasonable assurance provided by the examinations that were completed, re!!ef L

is granted pursuant to 10 CFR 50.55a(g)(6)(i).

RR-4 (Part 2). Examination Cateaorv B-K. Item B10.10. Intearally Welded Attachments to.

l Pressure Vessels:

l Category B-K, item B10.10, requires 100 percent surface examination of integrally welded attachments to pressure vessels as defined by Figures IWB-2500-13, -14, and -15, as applicable. Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from performing the surface examination, to the extent required by the Code, for the RPV integral attachment welds listed in its sut,m;ttal, due to physical obstructions. The staff finds that the requirements of the Code are impracScal and imposition of the requirements would require design modifications that v. auld result in a burden on the licensee. The licensee can examine a considerable portion (50 percent) of each of the subject welds. The partial surface examination should detect any significant patterns of degredation that may occur and provide reasonable assurance of the continued structuralintegrity of the RPV closure head lifting lugs. Based on r

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I the impracticality of meeting the Code-coverage requirements for the subject wolds, and the 1

reasonable assurance provided by the examinations that were completed, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

RR-5. Examination Cateaorv B-G-1. Item B6.10. Reector Pressure Ves==I (RPV) Clasure Head Nuts:

Evaluated and authorized in the staff's Safety Evaluation dated March 24,1998.

RR-6. Examination Catenories B-B and B-D. Items B2.40 and B3.140. Steam Generator Tubesheet-to-Shell Welds and Nozzle inside Radius Sections:

l Examination Category B-B, item B2.40 requires 100 percent volumetric examination of steam

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generator tubesheet-to-shell welds as defined by Figure IWB-2500-6. Examination Category B D, item B3.140 requires 100 percent volumetric examination of steam generator nozzle inner radius (IR) sections as defined by Figure IWB 2500-7. Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from the Code-coverage requirements for the l

steam generator examination areas listed in its submittal. The requirements of the Code are l

impractical due to component configuration and imposition of the sequirement would require design modification that would result in a burden upon the licensee. Based on the impracticality of meeting the Cods coverage requirements for the subject examination areas, and the reasonable &;surance of structural integrity provided by the examinations that can be L

completed, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i) for the tubesheet-to-shell welds.

l For the primary nozzle IR sections, it is concluded that the Code-coverage requirements are l

impractical, but that a VT-1 visual examination should be performed as performed during the

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first 10-year interval. Therefore, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i) provided the subject nozzle IR sections receive a VT-1 visual examination in lieu of the Code-required volumetric examination.

l RR-7. Examination Cateaories B-B and B-D. Items B2.11. B3.110. and B3.120. Pressurizer Circumferential Shell-to-Head Welds. Na'*le-to-Shell Welds. and Nozzle Inner Radius l

Sections l

l Examination Category B-B, Item B2.11 requires 100 percent volumetric examination of l

pressurizer circumferential shell to-head welds as defined by Figure IWB-2500-1. Examination Category B-D, Items B3.110 and B3.120 require 100 percent volumetric examination of pressurizer nozzle to vessel welds and nozzle inside radius sections as defined by Figure lWB-2500-7. Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from the Code-coverage requirements for the pressurizer. welds listed in the licensee's submittal. The requirements of the Code are impractical due to physical obstructions and imposition of the Code requirement would require design modifications that would result in a burden upon the licensee. Based on the impracticality of meeting the Code-coverage requirements for the subject examination areas, and the reasonable assurance of structural integrity provided by the i'

examinations that can be completed and the alternate examinations, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

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l RR-8. Examination Cateaorv B-K. Item B10.10. Intearally Welded Attachments to Pressure Vessels:

The RR was withdrawn by the licensee in its June 26,1998, submittal.

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RR-9. Ultrasonic Techniaues and Calibration Blocks for Examination of Cast Stainless l

Steel (Grfde SA 351-CF8A) for Reactor Coolant System (RCS) Ploina Welds:

Article Ill 2430 of ASME Section XI requires that manual ultrasonic examination scanning shall be done at twice (+6dB) the primary refm ance level as a minimum. ASME Section XI, Article 1, Supplement 1 (b) requires the calibration block thickness to be of a size sufficient to contain the entire examination path. For weld thicknesses over 2 inches, but less than 4 inches,Section V, Article 5, Figure T-542.2.1, requires calibration block thickness to be either 3 inches, or actual thickness.Section XI, Article lil, Paragraph 111-3410 requires that basic calibration blocks be made from material of the same nominal diameter and nominal wall thickness as that of the pipe to be examined. Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee proposed an alternative to the Code requirements for the examination of Grade SA 351-CF8A, cast stainless steel RCS piping welds. Calibrations will be performed utilizing two calibration blocks, one with a 2.45-inch nominal wall thickness and the other with a 3-inch nominal wall thickness. A demonstration using this technique was performed for NRC Region 11 and was determined to be a conservative method of detecting reflectors from the inside diameter. From the demonstration, the NRC inspectors determined that the calibration provided by the 2.45-inch thick block was as sensitive, if not more sensitive, than the calibration of the thicker block. This alternative is further supported by Code Case N-461, which has been approved for general use by reference in Regulatory Guide 1.147, Inservice Code Case Acceptability, ASME Section XI, Division 1, and allows calibration blocks to be used that are within 25 percent of the actual thickness.

Specifically, that would allow the use of blocks ranging from 2.25 inches thick to 3.75 inches thick. Based on the successful demonstration that was documented in the October 18,1994, NRC letter, and the guidance provided in Code Case N-461, the staff concludes that the examinations performed using the thinner calibration block will provide an acceptable level of quality and safety. Regarding demonstrating the proposed alternative to scan at reference sensitivity, current revisions of ASME Section XI, Appendix Vill, do not provide requirements for demonstrating techniques and procedures for cast stainless steel materials, therefore, the licensee will require inspection personnel to be qualified to Appendix Vill and will demonstrate the procedure on a mock-up or calibration block. Due to lack of guidance provided by the Code, and that the licensee will enhance the examination with demonstrations "in-the-spirit" of Appendix Vill. Therefore, the proposed examination at reference sensitivity will provide an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i) for the second 10-year ISI interval.

RR-10. Examination Cateaorv B-F. Item B5.130. Dissimilar Metal Piolaa Welds:

Examination Category B-F, item B5.130 requires 100 percent surface and volumetric examination, as defined by Figure IWB-2500-8, for Class 1 dissimilar metal piping welds, greater than, or equal to,4-inch nominal pipe size.

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Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from the Code coverage requirements for the dissimilar metal piping welds listed in its submittal since complete

l I volumetric examination is limited by nozzle configuration that restricts access to the examination area. The Code-coverage requirements are impractical for these welds. To meet the Code requirements, the nozzle welds would require design modifications to allow access for examination. Imposition of the Code requirements would result in a burden on the licensee.

The licensee can examine 50 percent of these welds. In addition, these welds are part of a larger sample of similar welds that can be examined. The limited volumetric examination, in conjunction with the examination of other similar welds should detect any significant patterns of degradation that may occur and provide reasonable assurarice of structuralintegrity of the subject dissimilar metal welds. Since, compliance to the Coc9-coverage requirement for the subject examination areas is impractical, and there is reasonaole assurance of structural integrity from examinations that can be comp!eted, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

1 RR-11. Examination Catenorv B-J. Item B9.31. Class 1 Branch Connection Welds; Examination Category B-J, item B9.31 requires 100 percent surface and volumetric examination, as defined by Figures IWB-2500-9, -10, and -11, for Class 1 branch connection welds in 4-inch nominal pipe size and larger. Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from the Code-coverage requirements for the Class 1 branch connection welds listed in the submittal since complete volumetric examination is limited by component configuration and weld design that restrict access to the examination area. The Code-coverage requirements are impractical for these welds. To meet the Code requirements, the nozzle welds would require design modifications to allow access for examination, imposition of the Code requirements would result in a burden on the licensee. The licensee can perform volumetric examination on a portion of each of these welds along with the complete surface examination. In addition, these welds are part of a larger sample of welds that can be examined. The limited volumetric examination, in conjunction with the Code surface examination and the complete examina! ion of other similar welds should detect any significant pattern of degradation that may occur and provida reasonable assurance of the structural integrity of subject branch connection welds. Since compliance with the Code-coverage requirement for the subject examination areas is impractical, and there is reasonable assurance of structural integrity from examinations that can be completed, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

RR-12 (Part 1). Examination Catenorv B-J. Item 99.11. Class 1 Circumferential Welds:

Examinatica Category B-J, item B9.11, requires 100 percent surface and volumetric examination of Class 1 pressure retaining circumferential piping welds as defined by Figure IWB 2500-8. Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from the Code-coverage requirements for the !!am B9.11 circumferential welds listed in the submittal since a complete ultrasonic examination is limited by component configuration and weld geometry, which restrict access to the Code-required examination volume. The Code-coverage requirements are impractical for these welds. To meet the Code requirements, design modifications would be necessary to allow access for examination. Imposition of these requirements would create a burden on the licensee. The licensee can examine at least 50 percent of each of the welds, in addition to the complete surface examination. In addition, these welds are part of a larger sample of welds that are being examined to the extent required by the Code. The limited volumetric examination in conjunction with the complete surface l

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_ examination and the complete examination of other similar welds should detect any significant pattern of degradation that may occur and provide reasonable assurance of the structural ir.tegrity for the subject welds. Since, compliance to the Code-coverage requirement for the subject welds is impractical, and there is reasonable assurance of structural integrity from examinations that can be completed, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

RR-12 (Part 2). Examination C*norv C-F-1. Item C5.11. CMse 2 Circumferential Welds:

Examination Category C-F-1, item C5.11 requires 100 percent sudace and volumetric examination of pressure retaining circumferential welds in austenitic stainless steel piping as defined by Figure IWC-2500-7. In accordance with 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from the Code-coverage requirements for the Class 2 circumferential welds in its submittal since a complete ultrasonic examination is limited by component configuration and weld geometry which restrict access to the Code-required examination volume. The Code-coverage requirements are impractical for these welds. To meet the Code requirements, design modifications would be necessary to allow access for examination. Imposition of these requirements would create a burden on the licensee. The licensee can examine at least 50 percent of each of the welds, in addition to the complete surface examination. In addition, these welds are part of a larger sample of welds that are being examined to the extent required by the Code. The limited volumetric examination in conjunction with the complete surface examination and the complete examination of other similar welds should detect any significant pattern of degradation that may occur and provide reasonable assurance of the structural integrity for the subject welds. Since compliance with the Code-coverage requirement for the subject welds is impractical, and there is reasonable assurance of structurel integrity from examinations that can be completed, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

BR-13. Examination Cateaorv B-J. Clas 1 Pressure Retainina Welds:

RR-13 was withdrawn by the licensee in its June 26,1998, submittal.

RR-14. Examination Catenories C-A and C-B. Items C1.20. C2.21. C2.22. and C2.31.

Class 2 Versel Welds. Nozzle-to-Vessel Welds. and Nozzle Inside Radius flR) Section11 i

Examination Category C-A, item C1.20 requires 100 percent volumetric examination, as defined by Figure IWC-2500-1, of circumferential head welds. Examination Category C-B, l

item C2.21 requires surface and volumetric examination, as defined by Figure IWC-2500-4(a) or (b), as applicable, for nozzle to-vessel welds without reinforcing plates, in vessels greater that 1/2-inch nominal wall thickness. Examination Category C-B, item C2.22 requires 100 percent volumetric examination, as defined by Figure IWC-2500-4(a) or (b), as applicable, for nozzle IR sections in nozzles without r4 'orcing plates in vessels greater that 1/2-inch nominal wall thickness. Examination Cabs C 8, item C2.31 requires 100 percent surface examination, as defined by Figure IWC-2500 %.) for nozzle reinforcing plate welds in vessels up to 1/2-inch nominal wall thickness.

Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from performing the surface and/or volumetric examinations, to the extent required by the Code, for the welds listed in the submittal, since access to these areas is limited by component configuration. The Code-required volumetric examinations are impractical to perform for these areas. To meet the

.. Code requirements, design modifications would be necessary to allow access for examination, which would create a burden on the licensee. The licensee can examine at least 50 percent of each weld. These examinations should detect any significant patterns of degradation and reasonable assurance of the structuralintegrity will be provided by the partial examinations.

Since compliance with the Code-coverage requirement for the subject examination areas is impractical, and there is reasonable assurance of structural integrity from examinations that can be completed, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

RR-15_, Examination Cateoorv C-F-1. Class 2 Pressure Retainina Welds:

RR 15 was withdrawn by the licensee in its June 26,1998, submittal.

RR-16. Examination Cateaory C-F-2. Item C5.51. Class 2 Carbon Steel Pipina Welds 1 Examination Category C-F-2, item C5.51 requires 100 percent surface and volumetric examination, as defined by Figure IWC-2500-7, for circumferential welds in carbon steel piping greater than or equal to 3/8-inch nominal wall thickness, and greater than 4-inch nominal pipe size. Pursuant to 10 CFR 50.55a(g)(5)(iii), the licensee requested relief from the Code-coverage requirements for the welds listed in the submittal since the weld configuration (pipe / valve) prevents access from one side of the welds. The Code volumetric examination is impractical to complete for these welds. Design modifications would be required to provide access for examination, and hence, imposition of the Code requirements would result in a burden on the licensee. The licensee can examine a significant portion of each weld from the pipe side and in the circumferential direction, in addition, the surface examination can be examined to the extent required by the Code. Therefore, the limited volumetric examination, in conjunction with the Code-required surface examination, should detect any significant patterns of degradation that may occur and provide reasonable assurance of the continued structural integrity for the subject welds. Since compliance with the Code-coverage requirement for the subject welds is impractical, and there is reasonable assurance of structuralintegrity from examinations that can be completed, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i).

RR 17. Examination Cateoorv C-F-1. Item C5.11. Class 2 Ploina Welds:

RR47 was evaluated and authorized pursuant to 10 CFR 50.55a(a)(3)(i) in an NRC Safety Evaluation dated October 24,1997.

RR-18. Examination Cateaory C-F-1. Items C5.11. C5.30. and C5.41. Class 2 Austenitic Stainless Steel Ploina Welds in the Nuclear Service Coolina Water (NSCW) System:

Examination Category C-F-1, item C5.11 requires 100 percent surface and volumetric examination, as defined by Figure IWC-2500-7, for Class 2 circumferential piping welds greater than or equal to 3/8-inch nominal wall thickness and greater than 4-inch nominal pipe size (NPS). Item C5.30 requires surface examination, as defined by Figure IWC-2500-7, for socket welds in piping greater than or equal to 3/8 inch nominal wall thickness and greater than 4-inch NPS. Item C5.41 requires surface examination, as defined by Figures lWC-2500-9 to

-13 inclusive, for circumferential branch connections of branch piping 2-inch NPS and greater.

Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee poposed an alternative to the Code requirements to exclude the NSCW system from the Class 2 weld population since this system

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-9 provides only a Class 3 cooling water functica and is not Class 2 in accordance with Regulatory Guide 1.26, Revision 3. This system is classified as Class 2, inside the containment, since there is only one isolation valve in the system ocated outside the containment. Had there been a second isolation valve inside the containment, only the small segment of piping in the NSCW system between the isolation valves would hve been Class 2, and the balance of piping would have been classified as Class 3 and would r.at have been included in the balance of Class 2 weld population for volumetric examination. Nevertheless, by including the welds in the NSCW system in the Class 2 weld population, the total volumetric examinations of Class 2 systems increase significantly because 7.5 percent of the population of all Class 2 welds would have to be considered. The staff noted that, even though the system is designated as Class 2, volumetric examination of welds in this system would not be required due to thickness considerauon. The system, however, is subject to a leakage test in accordance with Table IWD-2500-1 of the ASME Code,Section XI. The staff has determined that exclusion of welds inside the containment in this system from the total population of Class 2 welds, will not change the verification of structuralintegrity of the welds in this system since the inspection requirement is VT-2 examination with a system pressure test, which remains the same.

Consequently, the asses;, ment of structuralintegrity of welds in the balance of Class 2 systems will then be based on inspection of a 7.5 percent sample of an unbiased population of Class 2 welds. The staff has further determined that exclusion of NSCW system welds from the total population of Class 2 welds would be subjected to verification commensurate with its low system pressure and low wall thickness and will continue to provide an acceptable level of quality and safety and, therefore, the proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).

RR-19. Use of Code Case N-524. Alternative Examination Reaulrements for Lonaltudinal Welds in Class 1 and 2 Ploina for Examination of Class 2 Pipina Welds:

RR 19 was evaluated and authorized in an NRC Safety Evaluation dated March 24,1998.

RR-20. Use of Code Case N-509. Alternatj;g A.tes for the Selection and Examination of Class 1. 2. and 3 Intearally Welded Attaeb/.3tsj RR-20 was evaluated and authorized in an NRC Safety Evaluation dated March 24,1998.

RR-21. lWC-1220. Class 2 Components Exempt from Examination:

The requirements of IWC-1220, Components Exempt from Examination, contains the exemption criteria for Class 2 components. lWC-1222 contains the requirements for components within systems other than the Residual Heat Removal (RHR), Emergency Core Cooling (ECC), and Containment Heat Removal (CHR) systems. In accordance with IWC 1222, components exempt from the surface and volumetric examination requirements of IWC-2500 are as follows:

1 (a) Vessels, piping, pumps, valves, and other components NPS 4 and smaller.

(b) Component connections NPS 4 and smaller (including nozzles, socket fittings, and other connections) in vessels, piping, pumps, valves, and other components of any size.

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l 4 l (c) Vessels, piping, pumps, valves, and other components of any size in systems or portions of systems that operate (when the system function j

is required) at a pressure equal to or less than 275 psig and at a temperature equal to or less than 200"F.

'(d) Piping and other components of any size beyond the last shutoff valve in open ended portions of systems that do not contain water during normal plant operating conditions.

The licensee, pursuant to 10 CFR 50.55a(a)(3)(i), proposed an altemative to the 1989 Edition to use the exemption criteria found in lWC-1222 of the 1989 Addenda of the 1989 Edition of l

ASME Section XI for components within systems other than the Residual Heat Removal, Emergency Core Cooling, and Containment Heat Removal systems. These addenda do not require surface and volumetric examinations of vessels and their connections in piping 4-inch nominal pipe size (NPS) and smaller for Examination Category C-A, items Cl.10, Cl.20, and Cl.30 (Pressure-Retaining Welds in Vessels) and Examination Category C-C, item C3.10 (Integrally Welded Attachments to Pressure Vessels). Relief is specifically requested for the

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following components:

l Regenerative Heat Exchanger (Tag No.1-1208-E6-001) t Excess Letdown Heat Exchanger (Tag No.1-1208-E6-002)

Letdown Heat Exchanger (Tag No.1-1208 E6-003)

Letdown Reheat Heat Exchanger (Tag No.1-1208-E6-007)

Suction Damper (Tag No.1-1208-V4-001) l Discharge Dampener (Tag No.1-1208-V4-002)

Relief for comparable VEGP-2 welds was granted in the NRC staff's Safety Evaluation dated

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March 24,1998, as corrected by letter dated April 1,1998.

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The licensee has requested to use the exemption criteria of IWC-1222 of the 1989 Addenda in lieu of the exemption requirements of the Code of record. In accordance with the 1989 Code, piping NPS 4 and smaller is exempt from examination, but connected components are not. In the 1989 Addenda of Section XI, IWC-1222 was revised to exempt vessels, pumps, and valves, and their connections in piping NPS 1 and smaller, with the following note: "In piping is defined i'

as having a cumulative inlet and a cumulative outiet pipe cross-sectional area neither of which exceeds the nominal OD cross-sectional area of the designated size." This exemption is also contained in Code Case N-408-2, Altemative Rules for Examination of Class 2 Piping,Section XI, Division 1, which has been approved for general use in Revision 11 of Regulatory Guide 1.147, ISI Code Case Acceptability -- ASME Section XI, Division 1.

E i

The change in the Code previously described parallels the logic used for the exemption of j

Class 1 systems. Specifically, lWB-1220(b)(2) exempts " components and their connections in piping in 1-inch nominal pipe size and smaller," where "in piping" is defined as having one inlet i

and one outlet pipe, each of which is 1-inch NPS or smaller. The discrepancy between Class 1 j_

and 2 systems was recognized by the Code committee, which patterned the exemption criteria for Class 2 in the 1989 Addenda after existing exemption requirements for Class 1 systems.

ij The staff has concluded that the licensee's alternative, to use the exemption criteria of the 1989 Addenda for the above specified Class 2 systems, provides an acceptable level cf quality l

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I an' d safety. The approach used for the Class 2 exemption criteria found in the 1989 Addenda is similar to that used for exemption of Class 1 systems. In addition, the criteria has been approved by the NRC as part of Code Case N-408-2. Therefore, the licensee's proposed t

- alternative contained in RR-21 is authorized pursuant to 10 CFR 50.55a(a)(3)(i). Attachment 2 contains TER pages that replace the TER pages that were issued with the NRC letter dated -

April 1,1998.

. RR So Use of CM Case N-544. 5:,alr and Ree!Mement of Small items:

RR-22 was evaluated and authorized in an NRC Safety Evaluation dated March 24,1998.

RR-23. Use of Code Case N-498-1. Alternative Re!es for 10-Year Svatem Hvdra='=+1e Testina for Class 1. 2. and 3 Systems:

RR 23 was evaluated and authorized in an NRC Safety Evaluation dated March 24,1998.

L RR-24. Use of Code Case N-416-1i Alternative Pressure Test Reauire:wents for Welded Repairs or initialization of Replacement items by Weldina. Class 1. 2. and 3 Systems:

i RR-24 was evaluated and authorized in an NRC Safety Evaluation dated March 24,1998.

l RR-25 (hded September 17.1997L IWA-5250(aM2L Corrective Actions for Bolted l

E Connections:

RR-25 was evaluated and authorized in an NRC Safety Evaluation dated October 24,1997.

j mamination of Insulated Components:

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For systems borated for the purpose of controlling reactivity, Subparagraph IWA-5242(a) requires removal of insulation from pressure-retaining bolted connections for VT 2 visual examination during system pressure testing. Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee l

has proposed an alternative to the requirements of IWA-5242(a) to perform the VT-2 visual i

examination with the insulation in place and, in addition, a separate direct visual examination with the insulation removed but without pressurizing the system to be performed during each refueling outage for Class 1 components and every 40 months for Class 2 and 3 components, except when a reactor refueling outage is in progress or is scheduled to start within 6 months when the 40 months expire. In that case, insulation removal and subsequent VT-2 examination will be deferred until prior to plant startup following the refueling outage. The licensee's-proposed alternative is essentially equivalent to Code Case N-533, Alternative Requirements

,l-for VT-2 Visual Examination of Class 1 Insulated Pressure-Retaining Bolted Connections,Section XI, Division 1, except that the proposed altemative was extended to address Code j

. Class 2 and 3 bolted connections. Code Case N 533 is currently under review by the NRC staff v

and has not yet been approved for use by incorporation into Regulatory Guide 1.147, ISI Code i

Case Acceptability. The licensee's proposed attemative provides a systematic approach to ensure leak tight integrity of systems borated for the purpose of controlling reactivity. Initially, by performing the leakage test at operating pressure with the insulation in place, any significant leakage will be detected when the leakage either penetrates the insulation, or is detected at

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Joints or low points. Subsequently, by removing the insulation each refueling outage for Class 1

. 1 components and at 40-month intervals for Class 2 and 3 components, the licensee will be able to detect minor leakage indicated by the presence of boric acid crystals or residue. This two-phase approach will provide an acceptable level of quality and safety for bolted connections in borated systems and, therefore, the licensee's proposed altemative is authorized pursuant to 10 CFR 50.55a(a)(3)(i) for use on Class 1,2, and 3 systems. The use of this alternative is authorized for the second 10-year interval at VEGP, Units 1 and 2, or until Code Case N-533 is approved for general use by reference in Regulatory Guide 1.147. At that time, the licensee shuld follow the conditions, if any, specified in the regulatory guide.

RR-27. Use of Code Case N-546. Alternative Reauirements for Qualification of VT-2 Examination Personnel:

i Section XI, IWA-2300, requires that personnel performing VT-2 and VT-3 visual examinations be qualified in accordance with comparable levels of competency as defined in ANSI N45.2.6.

Additionally, the examination personnel shall have natural or corrected near distance acuity, in at least one eye, equivalent to a Snellen fraction of 20/20. For far vision, personnel shall have 1

- natural or corrected far distance visual acuity of 20!30 or equivalent. Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee proposed to use Code Case N-546, Alternative Requirements for

- Qualification of VT-2 Examination Personnel,Section XI, Division 1, as an alternative to the ASME Section XI qualification requirements for VT-2 visual examiners. In addition to meeting i

the requirements contained in Code Case N-546, the licensee's alternative includes the use of l

procedural guidelines for consistent VT-2 visual examinations, verification and maintenance of a

records of the qualification of persons selected to perform VT-2 visual examinations, and performance of independent reviews and evaluations of leakage found by a person (s) other than those that performed the VT-2 visual examination. The licensee, however, has taken an i

exception to the requirements of Code Case N-546 in complying with IWA-2321 of the 1995 Edition of ASME Code,Section XI, for visual acuity. As an alternative, the licensee has proposed to meet the requirement of IWA 2321 of the 1969 Edition as an alternative. The staff has determined that the qualification requirements in Code Case N-546 are not significantly 4

different from those for VT 2 visual examiner certification. Licensed and nonlicensed cperators, local leak rate personnel, system engineers, and inspection and nondestructive examination personnel typically have a sound working knowledge of plant components and piping layouts.

This knowledge makes them acceptable candidates for performing VT 2 visual examinations.

Regarding the use of the visual acuity requirements of the 1989 Code, the staff concludes that the use of the currently approved Code is sufficient to assure the visual acuity of examination personnel. Based on a review of Code Case N-546, as modified by the licensee, the licensee's proposed use of Code Case N-546 is authorized pursuant to 10 CFR 50.55a(a)(3)(i). The use of this Code Case is authorized for the second 10-year interval at VEGP, Units 1 and 2, or until the Code Case is approved for general use by reference in Regulatory Guide 1.147. At that time, the licensee must follow the conditions, if any, specified in the regulatory guide.

RR-28. Use of Code Case N-508-1. Rotation of Serviced Snubbers and Pressure Relief Valves for the Purpose of Testina:

RR-28 was evaluated and authorized in an NRC Safety Evaluation dated December 9,1997.

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t l RR-29. IWF-5000. ISI and Testina of Hydraulic and Mechanical Snubbers:

The licensee has requested relief from the requirements of ASME Code Section XI,1989 Edition, Article IWF-5000, with regard to visual examination and functional testing of hydraulic and mechanical snubbers. Article IWF-5000 references the first addenda to ASME/ ANSI OM-1987, Part 4 (OM-4) for such snubber activities. As an alternative, the licensee requested the use of Section 13.7.2 of the VEGP Technical Requirements Manuai(TRM) for the required snubber visual examination and functional testing with an additional commitment regarding the repair and replacement of certain components, pursuant to 10 CFR 50.55a(a)(3)(i). The VEGP TRM was accepted by the NRC on December 10,1996, as part of the improved Technical Specifications (ITS). Section 13.7.2 of the VEGP TRM is essentially the same as Article IWF-5000 except for the schedule for insenrice examination of snubbers as described in OM-1987, Part 4, Paragraph 3.2.3(b). OM 1987, Part 4 requires all snubbers to be visually examined every 18 months. The VEGP TRM incorporates the provisions of NRC Generic Letter (GL) 90-09, " Alternative Requirements for Snubber Visual inspection Intervals and Corrective Actions," dated December 11,1990, and allows the frequency of snubber examinations to be extended up to every 48 months, contingent upon the results of examinations.

The licensee stated in the December 10,1996, submittal that, in lieu of using Article IWF-5000, the ongoing examination and testing program will continue to be performed in accordance with the VEGP TRM. The existing examination and testing program are designed to demonstrate the functional integrity of the snubbers and are, at least, equivalent to the requirements of Article IWF-5000 and the provisions of NRC GL 90-09. The licensee stated that continued use of the exi:: ting snubber examination and testing program will substantially reduce nonbeneficial work activities and radiation exposure if the requirements of Article IWF-5000 were imposed.

The licensee also stated that personnel, who are required to witness, perform, and/or evaluate the inspection program, including visual examinations, will be qualified in accordance with plant administrative procedures. Besides, the functional testing of snubbers will be performed by trained personnel using a detailed plant procedure.

The staff has reviewed the licensee's submittal pertaining to the relief request from the requirements of the ASME Code for visual examination and functional testing of snubbers. The licensee stated that the VEGP TRM is unchanged from that which was previously approved for use in the VEGP Standard Technical Specifications with first 10-year interval RR-43. RR-43 was authorized by an NRC lettei dated November 26,1991, for VEGP-1 and December 17, 1991, for VEGP-2. The subsequent adoption and approval of the VEGP ITS included the relocation of the snubber program, unchanged, to the VEGP TRM. The licensee has stated that the proposed alternative provides a level of quality and safety equivalent to the requirements of Article IWF-5000 of the 1989 Edition of ASME Section XI.

While the VEGP TRM does not explicitly state that repair and replacement of snubbers will be in accordance with the ASME Code,Section XI,1989 Edition, the proposed alternative includes a commitment in Section 1.8, " Repair and Replacement Procedures," of the licensee's May 29, 1997, submittal, that:

Repairs and replacement for Code Class 1,2, and 3 and their supports will be performed to the requirements of the 1989 Edition of ASME Section XI except where requests for relief have been submitted to and approved by the NRC.

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l The NRC staff has determined that the proposed alternative (to use the existing VEGP TRM requirements for snubber surveillance activities, with the commitment contained in Section 1.8 of the licensee's May 29,1997, submittal), will provide an acceptable level of quality and safety.

Based on the information provided, the staff has determined that the licensee has presented an adequate justification for an alternative to the requirements of the ASME Code 1989 Edition,Section XI, Article IWF-5000 (which references OM-1987, Part 4), with regard to visual examination and functional testing of VEGP snubbers. The staff has determined that the alternative use of the VEGP TRM, as supplemented by the repair and replacement provisons noted above, for visual examination and functional testing of hydraulic and mechanical snubbers, will provide an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(a)(3)(i), the licensee's relief request for the second 10-year interval of the VEGP ISI program is authorized.

RR 30. Use of Code Case N-532. Alternative Reauirements to Repair and Replacement and Inservice Summarv Report Preparation and Submission as Reauired by IWA-4000 and IWA 6000:

Section XI, Paragraph IWA-6220 requires that the licensee prepare reports using NIS-1, Owner's Report for ISIS, and NIS-2, Owner's Report for Repair or Replacements; IWA-6230 requires that these reports be filed with the enforcement and regulatory authorities having jurisdiction at the plant site within 90 days of the completion of the ISI conducted during each refueling outage. Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee proposed to use Code Case N-532, Alternative Requirements to Repair and Repiacement and Inservice Summary Report Freparation and Submission as Required by IWA-4000 and IWA-6000,Section XI, Division 1, in lieu of the Code reporting requirements. The requirements associated with documentation of inservice examinations and repairs / replacements and the subsequent submittal of Forms NIS-1 and NIS-2 within 90 days following a refueling outage are administrative only. The staff finds that use of the alternatives to Code requirements contained in Code Case N-532 will continue to provide an acceptable level of quality and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i). The use of alternatives contained in Code Case N-532 are authorized for the current interval or until such time as the Code Case is published in a future revision of Regulatory Guide 1.147. At that time, if the licensee intends to continue to implement the alternatives of this Code Case, the licensee is to follow all provisions in Code Case N-532 with limitations issued in Regulatory Guide 1.147, if any.

RR-31. Examination Cateaorv B-A. Item B1.30. Reactor Pressure Vessel (RPV) Shell-to-Flanae Weld:

Examination Category B-A, item B1.30 requires 100 percent volumetric examination of the RP' V shell-to-flange weld as defined in Figure IWB-2500-4. In accordance with Examination Category B-A, Note (4), at least 50 percent of the length of the RPV flange welds must be examined by the end of the first 10-year inspection period. If the partial examination is conducted from the flange face, the remaining volumetric examinations required to be conducted from the vessel wall may be performed at or near the end of the inspection interval.

Pursuant to 10 CFR 50.55a(a)(3)(i), the licensee proposed an alternative to the examination requirements of the Code for the RPV shell-to-flange weld. The licensee has proposed complete deferral of the RPV shell-to-flange weld to the end of the 10-year interval. The

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' l licensee's proposed alternative la similar to Code Case N-521, which is authorized for use at Vogtle Units 1 and 2, to allow deferral of other reactor vessel welds and examination areas

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provided (a) no inservice repairs or replacements by welding have ever been performed on any of the subject areas, (b) none of the subject areas contain identifiea flaws or relevant conditions that currently require successive inspections in accordance with IWB-2420(b), and (c) the unit l

Is not in the first interval. These conditions are met for the shell to-flange weld. In addition, the i

licensee has reexamined the subject welds during the third period of the first 10-year interval.

By repeating this examination at the end of the previous 10-year interval, the licensee has established a new sequence of examinations that will not cause the successive examinations to exceed 10 years and hence, the proposed alternative will provide an acceptable level of quality

)

and safety. Therefore, the licensee's proposed alternative is authorized pursuant to 10 CFR l

50.55a(a)(3)(l).

3.0 CONCLUSION

The staff concludes that the Code requirements contained in RR-4 (Parts 1 and 2), RR-7, RR-10, RR-11, RR-12 (Parts 1 and 2), RR-14, and RR-16 are impractical. Therefore, the staff concludes that relief is granted pursuant to 10 CFR 50.55a(g)(6)(i). For RR-6, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i), provided that the licensee meets the conditions stated in this evaluation. The relief granted is authorized by law and will not endanger life or property or the common defense and is otherwise in the public interest given due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility.

Pursuant to 10 CFR 50.55a(a)(3)(i), it is concluded that for RR-1, RR-2, RR-9, RR-18, RR-21, RR 26, RR-27, RR-29, RR-30, and RR-31, the licensee's proposed alternatives will provide an acceptable level of quality and safety and, therefore, the proposed alternatives are authorized.

i The use of alternatives contained in Code Cases N-B32 and N-546 are authorized for the current interval or until such time as the Code Case is published in a future revision of Regulatory Guide 1.147. At that time, if the licensee intends to continue to implement the alternatives of this Code Case, the licensee is to follow all provisions in Code Cases N-532 and N-546 with limitations issued in Regulatory Guide 1.147, if any.

l By letter dated June 26,1998, the licensee withdrew RR-3, RR-8, RR 13, RR-15, and RR-17, which are deleted from the ISI Program Plan.

1 The staff evaluated and authorized RR-5, RR-17, RR-19, RR 20, RR-21, RR-22, RR-23, RR 24, RR-25, and RR-28 in previous Safety Evaluations.

Attachments: 1. Technical Evaluation Report L

2. Supplemental Technical Evaluation Report PrincipalContributors: D.Jaffe A. Lee P. Patnaik Date:

December 31, 1998

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