ML20073G037
| ML20073G037 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 03/31/1991 |
| From: | Beth Brown, Mudlin J EG&G IDAHO, INC., IDAHO NATIONAL ENGINEERING & ENVIRONMENTAL LABORATORY |
| To: | NRC |
| Shared Package | |
| ML20073F981 | List: |
| References | |
| CON-FIN-D-6022 EGG-MS-9028, NUDOCS 9105030095 | |
| Download: ML20073G037 (43) | |
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4 EGG MS 9028 ;
e TECHNICAL EVALUATION REPORT ON THE FIRST 10 YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN:
PHILADELPHIA ELECTRIC COMPANY, LIMERICX GENERATING STATION, UNIT 2, DOCKET NUMBER 50 353 B. W. Brown J. D. Hudlin Published March 1991
- l Idaho National Engineering Laboratory -
EG&G Idaho, Inc. .
Prepared for:
.U.S. Nuclear Regulatory Comission Washington, D.C. 20555 under DOE Contract No. DE-AC07-761001570 FIN No. 06022 (Project 5) i l
ABSTRACT This report presents the results of the evaluation of the Limerick Generating Station, Unit 2, First 10 Year Interval Inservice Inspection (ISI) Program, Revision 0, submitted February 26, 1990, including the requests for relief from the American Society of Mechanical Engineers (ASME)
Boiler and-Pressure Vessel Code Section XI requirements that the Licensee has determined to be impractical. The Limerick Generating Station, Unit 2,.
First 10-Year Interval ISI Program is evaluated in Section 2 of this report for (a) compliance with the appropriate edition / addenda of Section XI, (b) acceptability of examination sample, (c) correctness of the application of system or component examination exclusion criteria, and (j) compliance with ISI-related commitments identified during the Nuclear Regulatory Commission (NRC) review before granting an operating license. The requests for relief are evaluated in-Section 3 of this report.
This work was funded under:
U.S. Nuclear Regulatory Commission FIN No. 06022, Project 5 Operating Reactor Licensing Issues Program, Review of ISI for ASME Code Class 1, 2, and 3 Components p 11
- I SUINARY
. 1 The Licensee, Philadelphia Electric Company, has prepared the Limerick Generating Station, Unit 2, First 10 Year Interval inservice Inspection (ISI) Program, Revision 0, to meet the requirements of the 1986 Edition of the ASME Code Section XI except that the extent of examination for Code Class 1 piping welds has been determined by the 1974 Edition, Summer 1975 Addenda as permitted by 10 CFR 50.55a(b). The first 10 year interval began January 8 1990 and ends January 7, 2000.
The information in the Limerick Generating Station Unit 2, First 10 Year Interval 151 program, Revision 0, submitted February 26, 1990, was i reviewed. Included in the review were the requests for relief from the ASME i Code Section XI requirements that the Licensee has determined to be impractical. -
Based on the review of the Lime; tek Generating Station, Unit 2, First 10 Year Interval ISI Program, Revision 0, and the recommendations for .
granting relief from the IS! examination requirements that have been determined to be impractical, it is concluded that the Limerick Generating Station, Unit 2. First 10-Year Interval ISI Program, Revision 0, with the exception of Requests for Relief RR ll and RR 12 (in part), is acceptable andincompliancewith10CFR50.55a(g)(4).
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CONTENTS ABSin'ACT .............................................................. 11 SUMMAIY ............................................................... iii
- 1. INTRODUCTION ...................................................... 1
- 2. EVALUATION OF INSERVICE INSPECTION PROGRAM PLAN . . . . . . . . . . . . . . . 3. . . .
2.1 Documents Evaluated ............................................ 3 2.2 Compliance with Code Requirements .............................. 3 2.2.1 Compliance With Applicable Code Editions . . . . . . . . . . . . . . . . . . 3 2.2.2 Acceptability of the Examination Sample . . . . . . . . . . . . . . . . . . . . 4 2.2.3 E x c l u s i o n C r i t,e r i a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2.4 Augmented Examination Commitments .......................... 4 2.3 Conclusions .................................................... 5
- 3. EVALUATION OF RELIEF REQUESTS ..................................... 6 3.1 Class 1 Components ............................................. 6 3.1.1 Reactor Pressure Vessel .................................... 6 3.1.1.1 Request for Relief RR 01, Examination Category B A, items 81.11, Bl.12, and Bl.22, Re actor Pressure Yes sel Welds . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.1.1.2 Request for Relief RR 08. Examination Category B 0, Item 83.90, Reactor Pressure Vessel Nozzle to Vessel Welds .......................... 9 3.1.1.3 Request for Relief RR ll, Examination Category 8 N, Ites B8.10, Reactor Pressure Vessel Integrally Welded Attachments ................... 11 3.1.2 Pressurizer (DoesnotapplytoBWRs) 3.1.3 Heat Exchangers and Steam Generators (No relief requests) 3.1.4 Piping Pressure Boundary ................................... 12 .
3.1.4.1 Request for Oslief RR 10. Examination Category B F, Item B5.130, Class 1 Di s simil ar Metal Piping Welds . . . . . . . . . . . . . . . . . . . . . . . . . . 12 iv
l 3.1.5 Pump Pressure Boundary ..................................... 14
. 3.1.5.1 Request for Relief RR 02, Examination Category B L 2, item B12.20, Reactor Recirculation Pump Casings ............................. 14 3.1.6 Valve Pressure Boundary .................................... 17 3.1.6.1 Request for Relief RR 03, Examination Category B.M 2, item B12.50, Class 1 Valve Bodies ........................................... 17 3.1.7 General (No relief requests) 3.2 Class 2 Components ............................................. 19 3.2.1 Pressure Vessels ........................................... 19 3.2.1.1 Request for Relief RR 06, Examination Category C.A. Item C1.10. Residual Heat Removal Heat Exchanger Shell Circumferential Welds . . . . . . . . . . . . . 19 3.2.2 Piping (Noreliefrequests) 3.2.) Pumps ...................................................... 21 3.2.3.1 Request for Relief RR 07. Examination
- Category C G. Item C6.10 Residual Heat Removal and Core Spray Pump Casing Welds ............... 21 3.2.4 Valves (No relief requests) 3.2.5 General .................................................... 23 3.2,5.1 Request for Relief RR 05. Examination Category C C, items C3.10 and 3.30, Integrally Welded Attachments to Class 2 Pressure Vessels and Pumps ............................. 23 3.3 Class 3 Components (Noreliefrequests) 3.4 Pressure Tests (Noreliefrequests) 3.5 General ........................................................ 26 3.5.1 Ultrasonic Examination Techniques (No relief requests) 3.5.2 Exempted Components (No relief requests) 3.5.3 Other ................................................ ..... 26 3.5.3.1 Request for Relief RR 04, Examination Category F C, Item F3.50, Snubber Functional Testing ..................................... 26 y 1
. 3.5.3.2 Request for Relief RR 09 Examination CategoryF.A.SamplingPlanforClass1,2
, and 3 Piping Supports .................................. 26 3.5.3.3 Request for Relief RR 12, Authorization Request for Use of ASME Code Case (s) ................... 28 4
CONCLUSION ........................................................ 32
- 5. REFERENCES ........................................................ 34
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TECHNICAL EVALUATION REPORT ON THE FIRST 10 YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN:
PHILADELPHIA ELECTRIC COMPA.4Y, LIMERICK GENERATING STATION, UNIT 2, DOCKET NUMBER 50 353
- 1. INTRODUCTION Throughout the service life of a water cooled nuclear power facility, 10 CFR 50.55a(g)(4) (Reference 1) requires that components (including supports) that are classified as American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Class 1, Class 2, and Class 3 meet the requirement,, 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" (Reference 2), to the extent practical within the limitations of design, geometry, and materials of construction of the components. This section of the regulations also requires that inservice examinations of components and system pressure tests conducted during the initial 120 month inspection interval shall comply with the requirements in the latest edition and addenda of the Code incorporated by reference in 10 CFR 50.55a(b) on the date 12 months prior to the date of issuance of the operating license, subject to the limitations and modifications listed therein. The components (including supports) may meet requirements set forth in subsequent editions and addenda of this Code which are incorporated by reference in 10 CFR 50.55a(b) subject to the limitations and modifications listed therein. The Licensee, Philadelphia Electric Company, has prepared the Limerick Generating Station, Unit 2, First 10 Year Interval Inservice Inspection (ISI) Program, Revision 0, to meet the requirements of the 1986 Edition of the ASME Code Section XI except that the extent of examination for Class 1 piping welds has been determined by the 1974 Edition, Summer 1975 Addenda as permitted by 10 CFR 50.55a(b). The first 10 year interval began January 8, 1990 and ends January 7, 2000. _
Asrequiredby10CFR50.55a(g)(5),ifthelicenseedeterminesthatcertain l Code examination requirements are impractical and requests relief from them, 1
, thelicenseeshallsubmitinformationandJustificationstotheNuclear RegulatoryCommission(NRC)tosupportthatdetermination.
Pursuant to 10 CFR 50.55a(g)(6), the NRC will evaluate the licensee's determinations that Code requirements are impractical; alternatively, pursuantto10CFR50.55a(a)(3),thelicenseemustdemonstratethateither (i) the proposed alternatives would provide an acceptable level of quality i andsafetyorthat(ii)codecompliancewouldresultinhardshiporunusual !
difficulties without a compensating increase in the level of quality and safety. The NRC may grant relief and may impose alternative requirements that are determined to be authorized by law, will not endanger life or property or the common defense and security, and are otherwise in the public interest, giving due consideration to the burden upon the licensee that l
could result if the requirements were imposed on the facility.
The information in the Limerick Gennrating Station, Unit 2. First 10 Year Interval 15! Program, Revision 0 (Reference 3), submitted February 26, 1990, was reviewed, including the requests for relief from the ASME Code Section XI requirements that the Licensee has determined to be impractical.
- The review of the ISI Program Plan was performed using the Standard Review Plans of NUREG 0800 (Reference 4), Section 5.2.4, " Reactor Coolant Boundary inservice inspections and Testing," and Section 6.6. " Inservice Inspection of Class 2 and 3 Components."
The Limerick Generating Station, Unit 2, First 10 Year interval ISI Program is evaluated in Section 2 of this report for (a) compliance with the appropriate edition / addenda of Section XI, (b) acceptability of examination sample, (c) correctness of the application of system or component exami_nationexclusioncriteria,and(d)compliancewithISIrelated commitments identified during the NRC's review before granting'an operating license.
The requests for relief are evaluated in Section 3 of this report. Unless otherwise stated, references to the Code refer to the ASME Code,Section XI, 1986 Edition. Specific inservice test (IST) programs for pumps and valves -
are being evaluated in other reports.
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- 2. EVALUATION OF INSERVICE INSPECTION PROGRAM PLAN This evaluation consisted of a review of the applicable program documents to determine whether or not they are in compliance with the Code requirements and any license conditions pertinent to ISI activities. This section l describes the submittals reviewed and the results of the review. I 2.1 Documents Evaluated Review has been completed on the following information provided by the Licensee: l l
(a) Limerick Generating Station, Unit 2, Inservice Inspection Program l
First Ten Year Interval (2 volume set), Revision 0; and '
l (b) Limerick Generating Station, Unit 2, Inservice inspection Program First Ten Year Interval Reference Drawings (2 volume set).
2.2 Comoliance with Code Reauirements 2.2.1 Comoliance with Aopjicable Code Editions The Inservice Inspection Program Plan shall be based on the Code !
editions defined in 10 CFR 50.55a(g)(4) and 10 CFR 50.55a(b).
Based on the operating license date of June 22, 1989 for Limerick Generati".1 Station, Unit 2, the Code applicable to the first 10 year interval ISI program plan is the 1986 Edition of I Section XI. As stated in Section 1 of this report, the Licensee has written the Limerick Generating Station, Unit 2, First 10 Year Interval ISI Program, Revision 0, to meet the requirements of the 1986 Edition of ASME Code Section XI except that the extent of examination for Code Class 1 piping welds has been determined by the 1974 Edition, Summer 1975 Addenda as permitted by -
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2.2.2 8ttentability of the Examjnation Samole Inservice volumetric, surface, or visual examinations shall be performed on ASME Code Class 1, 2, and 3 components and their j supports using weld selection criteria, sampling sizes, and I schedules described in Section XI of the ASME Code and 10CFR50.55a(b). Sample size and weld selection have been implemented in accordance with the Code and appear to be correct.
2.2.3 Exclusion criteria The criteria used to exclude components from examination shall be consistent-with Paragraphs !WB 1220, !WC 1220, IWC 1230, IWO 1220, and 10 CFR 50.55a(b). The exclusion criter_ia have been applied by the Licensee in accordance with the Code as discussed in Paragraph 2.3 of the ISI Program and appear to be correct.
2.2.4 Auamented Examination Comitments In addition to the requirements specified in Section XI of the ASME Code, the Licensee has comitted to perform augmented examinations per the following documents:
(4) NRC Generic Letter 88 01, "Intergranuier Stress Corrosion Cracking"(Reference 5):
(b) NUREG 0619 "8WR Feedwater Nozzle and Control Rod Drive Return LineNozzleCracking"(Reference 6);
(c)IEBulletinNo.8013."CrackinginCoreSpraySpargers" (Reference 7)
(d)NUREG/CR-3052,"Closeoutof_IEBulletin8007: BWR Jet Pump -
AssemblyFailure"(Reference 8);
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(e) USNRC Mechanical Engineering Branch (MEB) Technical Position HEB31(NUREG0800,'NoBreak' Boundaries)(Reference 9):
(f)OutboardfeedwaterCheckValvesHV412F074Aand81 (g) $1L No.'455, 'Reconnendation for Additional 151 of Alloy 182 Nozzle Weldments' (Reference 10):
(h) Extended Examination Volume for Code Category 8 0 (response to NUREG0619):
(i) Examination of the Reactor Pressure Vessel Closure Head lifting Lugs (j) 'Non-Q Reactor Pressure Vessel Internal Components,"
FSAR Table 3.2 1 (Reference 11);
(k)SILNo.409,"IncoreDryTubeCracks'(Reference 12):
(1) SIL No. 420, ' Inspection of det Pump Sensing Lines" (Reference 13);
(m)SnubberExaminationandTestingProgram(Technical SpecificationSnubbers)(Reference 14);and
. (n)SnubberExaminationProgram(BOPSnubbers).
2.3 Conclusions Based on the review of the documents listed above, it is concluded that the Limerick Generating Station, Unit 2 First 10 Year Interval inservice Inspection Program, Revision 0, is acceptable and in compliancewith10CFR50.55a(g)(4). -
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- 3. EVALVATION OF RELIEF REQUEST 5 The requests for relief from the ASME Code requirements that the Licensee has determined to be impractical for the Limerick Generating Station, Unit 2, first 10 year inspection interval are evaluated in the following sections.
3.1 Class 1 Components 3.1.1 Reactor Pressure Vessel 3.1.1.1 Recuest for Relief RR 01. Examination Cateoorv B A. Items Bl.ll. Bl.12. and B1.22. Reactor Pressure Vessel hida Code Recuirement: ASME Section XI, Table IWB 2500 1, Examination Category B A requires a volumetric examination of 100% of the weld length of all reactor pressure vessel (RPV) circumferential and longitudinal shell welds and all meridional bottom head welds during the first inservice inspection
- interval. These examinations shall be performed as defined in Figures IWB 25001, 2, and .3, as applicable.
Licensee's Code Relief Recuest: Relief is requested from examining 100% of the Code required volume (CRV) of the following RPV welds:
Weld Code CRV-Ident. Item No. [xaminable AA Bl.11 89.4 %
AC B1.11 89.2 %
AE Bl.11 88.3 %
BA Bl.12 85.65%
BB Bl.12 85.65%
BC Bl.12 85.2 %
BF Bl.12 76.0 %
BG Bl.12 79.3 % -
BK Bl.12 49.0 %
BM B1.12 47.9 %
BN 81.12 74.5 %
BP Bl.12 75.1 %
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OA 11em Not CRV Examinab_le Bl.22 B4.3 %
08 DC Bl.22 84.3 %
Bl.22 84.3 %
DF Bl.22 84.3 %
Bl.22 84.3 %
Licensee's Prooosed Alternative Examination: None. The Code required volumetric examination will be performed to th maximum extent practical.
Licensee's Basis for Reauestino Relief: Complete examination of the subject welds is not practical due to scanning limitations and access restrictions from various RPV appurtenances (e.g., adjacent RPV nozzles and attachments, the biological shield wall, and control rod drive housings).
The circumferential and longitudinal shell welds are -
examined using automated ultrasonic examination techniques to the maximum extent practical.
yield increases in examination coverage; however, t increases exposure. come at a cost of increased personnel radiation Therefore, due to ALARA considerations, supplemental' manual ultrasonic examinations are not being considered to augment examination coverage.
Manual ultrasonic examination of the bottom head we performed to the maximum extent practical.
The Licensee states that any significant improvement in automated or manual examination coverage cannot be achieved without c.cjor plant redesign.
Evaluation: As confirmed by review of the table attached to the relief request and drawings of the RPV, the volumetric examination of the RPV shell and head welds listed above is limited by adjacent nozzles and attachments, the biological shield wall, and control rod drive housings. The reactor vessel design, therefore, makes the volumetric examinations impractical to perform to the extent required by the Code. In order to examine the welds in accordance with the requirements, the reactor vessel would have to be redesigned, fabricated, and installed. Imposition of the requirements on Philadelphia Electric Company would cause a burden that would not be compensated significantly by an increase in safety above that provided by the proposed examination.
The Licensee has stated that the volumetric examinations of the subject RPV welds will be performed to the maximum extent practical. The percentages (listed above) of the Code required volumetric examinations that can and will be completed are significant and are consistent with other plants of similar
- design. The limited Section XI volumetric examinations will provide adequate assurance that unallowable inservice flaws have not developed in the subject reactor vessel welds or that they will be detected and removed or repaired prior to the return of the reactor vessel to service.
Conclusions:
It is concluded that the volumetric examination of the subject welds is impractical to perform at Limerick, Unit 2, to the extent required by Section XI of the ASME Code and that public health and safety will not be endangered by-allowing the limited Section XI volumetric examination to be performed in lieu of the Code requirement. Therefore, it is recommended that relief be granted as requested.
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3.1.1.2 Reouest for Relief RR 08. Examination Cateoory B D. Item B3.90.
l Reactor Pressure Vessel Nozzle to Vessel Welds Code Raouirement: Section XI, Table IWB 25001, Examination Category B 0, Item B3.90 requires a 100% volumetric examination
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of all RPV nozzle to vessel welds during the first inservice I inspection interval. These examinations shall be performed as defined by Figure IWB 2500 7(b).
1 Licensee's Code Relief Reauest: Relief is requested'from examining 100% of the Code required volume (CRV) of the following RPV nozzle to vessel welds:
Nozzla Transverse Scan Parallel Scan Identification CRV Examinable CRV Examinable NIA,B 19.29% 50%
N2A H,J,K 77.55%' 50% '
N3A,B,C,0 73.26% 50%
N4A,B,C,0,E,F 77.55% 50%
NSA,8 77.55% 50%
N6A,8 72.36% 50%
N7 76.24% 50%
N8A,8 78.22% 50%
N9 78.22% 50%
N17A,B,C,0 77.55% 50%
Licensee's Prooosed Alternative Examination: None. The Code required volumetric examination will be performed to the maximum extent practical.
Licensee's Basis for Reouestino Relief: The above subject nozzles have access limitations imposed by.the reactor pressure vessel design and/or component configuration.
l The Limerick Generating Station, Unit 2. reactor pressure '
i vessel has 34 nozzles, the welds of which require volumetric examination per the Code. Due to the nozzle forging configuration, portions of the Code required examination volume-cannot be completely examined. The curvature of the blend radius of the nozzle forging is such that ultrasonic scanning 9
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of the teld is interrupted due to loss of contact of the ultrasonic search unit. This limitation affects both transverse and parallel scanning of the Code required examination volume.
The Licensee also reports that in support of ALARA, 28 of the 34 nozzle to vessel welds are examined utilizing remote automatic ultrasonic techniques. These techniques, however, further limit the examination coverage due to scanning limitations caused by the scanner design.
Evaluation: The nozzle forging configuration is such that the volumetric examination of the subject RPV nozzle to vessel welds is restricted. Therefore, the volumetric examinations are impractical to perform to the extent required by the Code.
In order to examine the welds in accordance with the requirements, the nozzles, and thus the reactor vessel, would require redesign. Imposition of the requirement on Philadelphia Electric Company would, therefore, cause a burden '
that would not be compersated significantly oy an increase in safety above that provided by the limited examination.
The Licensee has stated that the volumetric examination of these welds will be performed to the maximum extent practical.'
The percentages (listed above) of the Code-required volume that can and will be completed are consistent with other plants of similar design. The limited Section XI volumetric examination of these welds will provide reasonable assurance of the continued inservice structural integrity.
Conclusions:
It is concluded that the volumetric examinations of the subject RPV nozzle-to vessel welds are impractical to perform at Limerick, Unit 2, to the extent required by Section XI of the ASME Code and that public health and safety will not be endangered by allowing the limited Section XI 1
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examination to be performed in lieu of the Code requirement.
Therefore, it is recommended that relief be granted as requested.
1 i
- 3.1.1.3 Reauest for Relief RR-11. Examination Cateaory B H. Item B8.10. .
Reactor Pressure Vessel Inteorally Walded Attachments Code Reauirement: Section XI, Table IWB 2500 1 Examination Category B H, Item B8.10 requires. a 100% surface examination of all RPV integrally welded attachments as defined by Figure IWB-2500 13, 14 -or -15, as applicable.
Licensee's Code-Relief Reauest: Relief is requested from examining -100% of the Code-required surface (CRS) of the following RPV integrally welded a'ttachments:
CRS Comoonent Identification f,xaminable 45' Stabilizer Bracket 61.3% "
135' Stabilizer Bracket 61.3%
225' Stabilizer. Bracket 61.3%
315' Stabilizer Bracket 61.3%
FR (RPV skirt attach.) 75%
Licensee's Procosed Alternative Examin'ation: In addition to the Code required surface examination being performed to the maximum extent practical, a VT-1 visual examination will be performed to the extent practical in areas where the required surface examinations-are incomplete.
Licensee's Basis for Reauestina Relief: Access to four of l eight stabilizer bracket attachment welds is limited due to mirror insulation support brackets affixed-to the stabilizer bracket lugs. These insulation support brackets preclude L ; equipment access necessary for complete magnetic particle ,
l~ examination of the weld and required area.
Access-for examination equipment is also limited in the area of skirt-attachment weld buildup. The configuration of the RPV 11
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, skirt knuckle to the bottom head limits access for complete examination of the underside of the weld. -
Evaluation: As described by the Licensee, the Code required surface examination of the subject welds may be impractical because of the physical size of magnetic particle equipment.
However, the Licensee has not discussed the impracticality of performing the Code required surface examination using liquid penetrant testing techniques.
[2nc]usions: Based on evaluation of the Licensee's submittal of request for relief RR ll and review-of Drawings XI BH 3 (RPV Stabilizer Brackets) and XI BN (RPV Layout), it is concluded that the surface examination of the subject welds is not impractical to perform to the extent required by the Code using liquid penetrant testing techniques. Therefore, it is recommended that relief be denied.
3.1.2 Erg 13urizer (Does not apply to BWRs)
~3.1.3 Heat Exchancers and Steam Generators (No relief requests) 3.1.4 Pioino Pressure Boundary 3.1.4.1 Recuest for Relief RR 10. Examination Cateoory B F.
Item B5.130. Class 1 Dissimilar Metal Pioino Welds Code Reouirement: Section XI. Table IWB 2500-1, Examination
-Category 8 F, Item 85.130 requires a 100% volumetric and surface examination of Class 1 pressure retaining dissimilar metal welds as defined by Figure IWB-2500-8.
Licensee's Code Relief Reauest: Relief is requested from examining 100% of the Code required volume (CRV) of the following Class 1 pressure retaining dissimilar metal welds:
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CRV RglL!dentification Examinable
, DLA 212 1 FW1 85%
DLA 212 2 FW1 85%
OLA 212 3 FW1 85%
DLA 212 4 FW1 85%
OLA 211 1 FW7 80%
Licensee's Prooosed Alternative Examination: None. In addition to the Code required surface examination, the Code required volumetric examination will be performed to the' maximum extent practical (see above table).
Licensee's Basis for Recuestina Relief: The 1.icensee reports that complete examination of the required examination volume of Figure IWB-2500 8 is not practical utilizing current ultrasonic examination techniques. Nonparallel surfaces within the required axial scan path on certain valves and fittings limit complete examination of the base material adjacent to the weld.
A complete ultrasonic examination scanning parallel to the weld' and a complete surface examination can be performed on the affected welds. Axial scanning of the weld and required volume will be performed to the maximum extent practical.
Evaluation: All five of the subject welds are valve to-flued head welds which limit volumetric examinations due to component configuration. Therefore, the volumetric examination of the subject Class 1 pressure retaining dissimilar metal welds is impractical to perform to the extent required by the Code, in order to examine the welds in accordance with the requirement, these components would require design modifications.
Imposition of the requirement on Philadelphia Electric Company would, therefore, cause a burden that would not be compensated significantly by an increase in safety above that provided by the proposed examination.
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The Licensee has stated that the Code required surface '
4 examination will be performed and that the volumetric examination will be performed to the maximum extent practical.
l A significant percentage (80% or greater) of the Code required volumetric examination can and will be performed. Therefore, the limited Section XI volumetric examination, along with the Code required surface examination, will provide dequate ;
assurance that unallowable inservice flaws have not developed in the subject welds or that they will be detected and removed or repaired prior to the return of the piping to service. '
Conclusions:
It is concluded that the volumetric examination i of the subject dissimilar metal welds is impractical to perform at Limerick, Unit 2, to the extent required by Section XI of j
.the ASME Code and that public health and safety will not be I endangered by allowing the proposed examination to be performed
-in lieu of the Code requirement. Therefore, it is recommended 3
that relief be granted as requested. 1 3.1.5 Pumo Pressure Boundary 3.1.5.1 Reauest for Relief RR-02. Examination Cateaory B-l 2.
Item B12.20. Reactor Recirculation Pumo Casinas t Code Reauirement: Section XI, Table IWB 2500 1. Examination Category B L-2, item 812.20 requires a 100% VT 3 visual examination of the internal surfaces of at least one of the two reactor recirculation pump casings during the first inservice inspection interval.
Licensee's Code Relief Reauest: Relief is requested from performing the Code-required VT-3 visual examination of the reactor recirculation pump casings.
14
Licensee's Procosed Alternative Examinat.Lon: The Code required
. VT 3 visual examinations will be performed on the accessible internal surfaces of one reactor recirculation pump should the required inspection area of either pump become accessible as a result of disassembly of the pump for other purposes, i
Licensee's Basis fer Recuestina Relief: The Licensee reports l that, in the absence of any other required maintenance on l either of the reactor recirculation pumps, the hardships associated with pump disassembly, solely for the purpose of visual inspection of the internal surfaces, far exceed any l safety benefits resulting from such an inspection.
The disassembly of a reactor recirculation pump at Limerick Generating Station, Unit 2, constitutes a maintenance task of major proportions measured both in terms of manhours and associated personnel exposure.
Evaluation: The visual examination is performed to determine if unanticipated severe degradation of the casing is occurring due to phenomena such as erosion, corrosion, or cracking.
However, experience with similar pumps at other plants has not shown any significant degradation of pump casings. Because of -
this, later editions and addenda of the ASME Code (1988 Addenda) have eliminated disassembly of pumps for the sole purpose of performing examinations of the internal surfaces and state that only pumps that are disassembled for reasons such as maintenance, repair, or volumetric examination must have their internal surfaces examined.
Philadelphia Electric Company has stated that the Code required visual examination will be performed on the internal pressure boundary surface of one reactor recirculation pump if one of the two pumps is disassembled such that access for conducting the examination is provided.
15
l
- I Examination of internal surfaces of pumps necessitates complete l disassembly of the pump which, in addition to the possibility of damage to the pump, would result in personnel receiving excessive radiation exposure. The disassembly of the reactor
. -recirculation pumps for the sole purpose of visual examination of the casing internal surfaces is a major effort and requires many manhours from skilled maintenance and inspection personnel. The increase in plant safety would not compensate for the burden placed on the Licensee that would result from imposition of the requirement.
Since no major problems have been reported in the industry with regard to pump casings, the Licensee's proposal will provide adequate assurance of the continued inservice structural integrity.
Conclusions:
The disassembly of a pump for the sole purpose of, inspection is impractical to perform at Limerick, Unit 2, j because this activity, in addition to the possibility of damage to the pump, would result in personnel receiving excessive radiation exposure. Imposition of the requirements on
~ Philadelphia Electric Company would cause a burden that would not be compensated significantly by an increase in safety above that provided by the proposed examination. Therefore, it is-concluded that public_ health and safety will not be endangered by allowing the proposed examination to be performed in lieu of the Code requirement. It is recommended that relief be granted provided that, if the pump has not been disassembled, this fact should be reported by the Licensee in the ISI Summary Report at the end of the interval.
l-
-l l
16 l ,
i L
, 3.1.6 Valve Pressure Boundarv 3.1.6.1 Reauest for Relief RR 03. Examination Cateoory B M 2m_
_ Item B12.50. Class 1 Valve Bodies Code Reouirement: Section XI Table IWD 2500 1. Examination Category B M 2, Item B12.50 requires a 100% VT 3 visual examination of the internal surfaces of one valve within each group of valves that are of the same constructional design and manufacturing method and that perform similar functions in the system, once during the first inservice inspection interval.
Licensee's Code Relief Recuest: Relief is requested from performing the Code required VT 3 visual examination of valve body internal surfaces.
Licensee's Procosed Alternative Examination: If, in the course of plant maintenance activities, the internal surfaces of the
~
body of an Examination Category B M 2 valve, within any of the valve groupings, becomes accessible, then a VT 3 visual examination will be performed on that valve to meet the examination requirements for that grouping.
Licensee's Basis for Recuestino Relief: The Licensee states that the requirement to disassemble Class 1 valves solely for the purpose of performing a visual examination of the internal surfaces of the valve body is impra:tical. The hardships and potential hazards associated with disassembly far outweigh any foreseeable increase in plant safety resulting from the examination.
Many of the subject valves are nonisolatable from the reactor pressure vessel and would require off loading of fuel and -
l draining the reactor pressure vessel prior to disassembly for examination. Other valves would require the installation of i
17 3
plugs in associated system piping. Personnel radiation exposure to perform disassembly of any of the valves is also a majorconsideration. .<
Evaluation: The visual examination is performed to determine if unanticipated severe degradation of the valve body is occurring due to phenomena such as erosion, corrosion, or cracking. However, experience with similar valves at other plants has not shown any significant degradation of valve ,
bodies. Because of this, later editions and adden'da of the ASMECode(1988 Addenda)haveeliminateddisassemblyofvalves for the sole purpose of performing examinations of the internal surfaces and state that only valves that are disassembled for reasons such as maintenance, repair, or volumetric examination must have their internal surfaces examined.
Philadelphia Electric Company has stated that the Code required visual examination will be performed on the internal pressure ,
boundary surface of one valve in each of the groups of valves if maintenance activities require disassembly of a valve such that access for conducting the examination is provided.
Examination of intarnal surfaces of a valve body necessitates complete disassembly of the valve which, in addition to the possibility of damage to the valve, would result in personnel receiving excessive radiation exposure. The disassembly of the subject valves for tho' sole purpose of visual examination of the valve body internal surfaces is a major effort'and requires many manhours from' skilled maintenance and inspection personnel. The increase in plant safety would not compensate for the burden placed on-the Licensee that would result from imposition of the requirement.
Since no major problems have been reported in the industry with regard to valve bodies, the Licensee's proposal will provide 18 2 . . . _ . . _ . ._ _ _ _ _ _ . _ _ _ _ ___ _.___ __
. adequate assurance of the continued inservice structural integrity.
Conclusioni: The disassembly of a valve for the sole purpose of inspection is impractical to perform at Limerick, Unit 2, because this activity, in addition to the possibility of damage to the valve, would result in personnel receiving excessive radiation exposure. Imposition of the requirements on Philadelphia Electric Company would cause a burden that would not be compensated significantly by an increase in safety above that provided by the proposed examination. Therefore, it is concluded that public health and safety will not be endangered by Allowing the proposed examination to be performed in lieu of
, the Code requirement. It is recommended that relief be granted provided that, if the valve has not been disassembled, this fact should be reported by the Licensee in the ISI Summary Report at the end of the interval.
3.1.7 General (Noreliefrequests) 3,2 Class 2 Comoonents -
3.2.1 Er.ntyre Vessels 3.2.1.1 Reauest for Relief RR 06. Examination Cateoory C A. Item Cl.10.
Residual Heat Removal Heat Exchancer Shell Circumferential Etidi Code Reauirement: S6ction XI, Table IWC 25001. Examination Category C-A, Item C1.10 requires a 100% volumetric examination of Class 2 pressure vessel shell circumferential welds at gross structural discontinuities as defined by figure IWC-2500-1.
Examination is required on only one residual heat removal (RHR) heat exchanger.
19
Licensee's Code Relief Reouest: Relief is requested from examination of 100% of the Code required volun,e of the shell to flange weld on one of the two Class 2 RHR heat exchangers.
Licensee's Prooosed Alternative Examination: None. The Code required volumetric examination will be performed-to the inaximum extent practical.
Licensee's Basis for Reauestina Relief: Complete ultrasonic examination of the shell to flange weld (on either heat exchanger) is limited due to access restrictions from the flange bolting. Bolting protruding through the vessel flange prohibits completion of the required ultrasonic scanning parallel to the weld. Transverse scans can be performed from the shell side of the weld, thereby providing approximately 87.5% coverage of the Code required volume. Disassembly of the
~
flange mechanical connection, to facilitate complete examination, is not practical and represents significant hardship in exchange for minimal benefit.
Evaluation: The volumetric examination of the subject RHR hc.it.
exchanger shell to flange weld is impractical to perform to the extent required by the Code because of the obstruction of the bolting protruding through the vessel flange. The Licensee has stated that the volumetric examination of the RHR heat exchanger shell-to flange weld will be performed to the maximum extent practical. A significant percentage (87.5%) can-and will be examined. In order to examine the remaining 12.5% of the weld, the flange connection would have to be disassembled.
In addition to ALARA concerns, the disassembly would be a significant effort and would require many manhours from skilled maintenance and-inspection personnel. Imposition of this requirement on Philadelphia Electric Company would cause a burden that would not be compensated significantly by an 20
, increase in safety above that provided by the proposed examination.
Thus, the limited Section XI volumetric examination will provide adequate assurance that unallowable inservice flaws have not developed in the weld or that they will be detected and removed or repaired prior to the return of the RHR heat exchanger to service.
Conclusions:
It is concluded that the volumetric examination of the subject weld is impractical to perform at Limerick, Unit 2, to the extent required by Section XI of the ASME Code and that public health and safety will not be endangered by allowing the limited volumetric examination to be performed in lieu of the Code requirement. Therefore, it is recommended that relief be granted as requested.
3.2.2 Pioino (Noreliefrequests)
- 3.2.3 hmal 3.2.3.1 Recuest for Relief RR 07. Examination Cateoory C G. Item C6.10.
Residual Heat Removal and Core Sorav Pumo Casino Weldt Code Rtautrement: Section XI, Table IWC 2500 1, Examination Category C G, Ites C6.10 requires a 100% surface examination of Class 2 pressure retaining pump casing welds of one pump in each~groupofmultiplepumps(ofsimilardesign, size, function,andservice)duringthefirstinspectioninterval.
Examination shall be as defined by Figure IWC 2500 8.
Licensee's Code Relief Reauest: Relief is requested from -
performing the Code required surface examination of the pressure retaining pump casing welds on the RHR and core spray pumps.
21
- . .x -. .. .- -
l
, licensee's Prooosed Alternative Examination: In the event any or all.of the subject welds become accessibl6 upon disassembly l of any one of the pumps, the welds will be surface examined from the inside surface to meet the Section XI requirements for that particular pump group. Alternatively, in support of ALARA, a VT 1 visual examination will be performed in lieu of a surface examination. The examination method will be determined by the Licensee based on radiation environment data at the time of access.
Licensee's Basis for Recuestina pelieft Welds on each of the RHR and core spray pumps (four welds on RHR and four welds on corespray)areencasedinconcreteandaretotally inaccessible for surface examination. Due to the design of the ,
subject pumps, access to the affected welds can only be achieved through disassembly of the pump, removal of the pump -
internals, and the required surface examination performed from the inside surface of the welds, a
Evaluation: As stated by the Licensee, four of the welds on each of the subject pumps are encased in concrete. Therefore, the Code-required surface examination of the subject welds is impractical to perform. The disassembly of the pumps for the sole purpose of inspection is a major effort and could result in damage to the pumps. Requiring Philadelphia Electric Company to disassemble the pump and remove the pump internals to perform the Code-required surface examination would cause a burden that would not be compensated significantly by an increase in safety above that provided by the proposed alternative.
The Licensee's proposed alternative is to examine these welds if any of the subject pumps are disassembled for repair or -
maintenance. The remaining accessible casing welds in each of one RHR and one core spray pump will be surface examined to Section XI requirements. In addition, all pumps are subject to the visual examination requirements of Examination Category C H 22
and the functional test requirements of Section lWp, thereby providing reasonable assurance of the continued inservice
- structural integrity.
Conclusions:
It is concluded that the surface examination required by Section XI of the ASME Code for the subject welds is impractical to perform at Limerick, Unit 2, and that public health and bafety will not be endangered by allowing the alternative examination to be performed in lieu of the code requirement. Therefore, it is recommended that relief be granted provided that, if the pumps have not been disassembled, this fact should be reported by the Licenste in the ISI Summary Report at the end of the interval.
'3.2.4 Valves (No relief requests) 3.2.5 General 3.2.5.1 Reauest for Relief RR 05. Examination Cateaory ~C-C. Items C3.10__
and C3.30. Intearall'/ Welded Attachments to Class 2 Pressure Vessels and Pumos Code'Recuirement: Section XI, Table IWC 2500 1 Examination Category C-C, Items C3.10 and C3.30 both require surface examination of 100% of required areas of each welded attachment
.to vessels and pumps during the first instrvice inspection
' interval.- In the case of multiple vessels, only the integrally welded attachments of one vessel in a group of vessels of similar design and service (or t: equivalent of one vessel) need be examined. The exarainations shall be as defined by-Figure IWC-2500 5.
Licensee's Code Relief Recuert: Relief is requested from
- examining 100% of the Code-required surface (CRS) of each of the following integrally welded attachments to Class 2 pressure vessels and pumps
23 u _ ._. 2_ _ _ _ _ _ _ _ _ _ _ _ . - - ,__ _ _ _ - _ _ - _ _ __, _
.___.-._._..________..__._.-_-.y RHR Heat Exchanaer Tie Down Brackets ,
Attachment CRS l
.- Identif< cation Examinabl.a l 2AE 20!i "D 1 04 (Relief for 2BE 205 TD 2 0% interior welds 2AE 205 TD 3 0% only) 28E 205 TD 4 0%
RHR Heat Exchanaer Hogntina suonorts Attachment CRS Identification Examinable
. 2BE 205 MS 1 75% (Relief for 2AE 205 MS 2 75% outside welds i3E 205 MS 3 75% only) 2AE 205 MS 4 75%
RCIC Pumo Mountina Sucoort Attachment CRS _.
Identification Examinable 20P 203 PS 1 84%
20P 203 PS 2 84%
20P 203 PS 1 84%
20P 203 PS-4 84%
Licensee's Procosed Alternative Examination: None. The Code required surface examination will be performed to the -
maximum extent practical.
Licensee's Basis for Reauestino Relief: Examination of the interior welds on the tiedown brackets for the RHR heat exchanger is limited due to insertion of tho tiedown anchor plates; the outside welds are completely accessible.
Examinations are limited on toth-RHR heat exchangers.
Examination of the outside attachment welds on the. mounting support-attachments for the RHR heat exchanger is limited by.
the supporting "I" beam. The inside welds are completely accessible. Examinations are limited on both RHR heat exchangers.
Examination of the bottom portion of th'e mounting support L attachment welds on the RCIC pump is limited due to proximity -
to the pump pedestal.
1 24
[
l i.
l
= . - . _ ,
The Licensee reports that increased examination coverage is not possible without undue hardship, such as a plant modification.
Evaluation: The configuration and location of support attachments are such that the surface of the subject integral attachment welds cannot be fully examined. Therefore, the surface examination of the subject integrally welded attachments is impractical to perform to the extent required by the Code. In order to examine the welds in accordance with the requirements, the plant / components would require design modifications. Imposition of the requirement on Philadelphia Electric Company would, therefore, cause a burden that would not be compensated significantly by an increase in safety above that.provided by the proposed examination, w
The Licensee has stated that the surface examination of these welds will be performed to the maximum extent practical. Based on the design, a t,;.sonable percentage of the Code-required ,
surface examination can and wil.1 be performed, thereby, providing reasonable assurance of the continued inservice structural integrity,
Conclusions:
It is concluded that the surface examination of the subject-integrally welded attachments is impractical to perform at Limerick,. Unit 2, to the extent required by Section XI of the ASME Code and that public health and safety will not be endangered by allowing a limited surface examination to be performed in lieu of the Code requirement.
Therefore, it is recommended that relief be granted as requested.-
3.3 Class 3 Components (No relief requests) 3.4 l Pressure Tests (No relief requests) '
25
. 3.5 General 3.5.1 Ultrasonic Examination Techniouti (No relief requests) 3.5.2 Exemoted comoonenti (No relief requests) 3.5.3 Q1hgr 3.5.3.1 Reouest for Relief RR-04. Examination Cateoory F C Item F3.50.
Snubber Functional Testino SQlE: The functional testing of snubbers is not included in this evaluation. Functional tests are not in tne scope of this document and will be evaluated elsewhere.
3.5.3.2 Reouast for Relief RR 09. Examination Cateoory F-A Samolino Plan For Class 1. 2. and 3 Pioino Sucoorts (qdg_Beauirement: Section XI, Paragraph IWF 2510 requires that component supports selected for examination be supports of those components that are required to be examined under IWB, IWC, and IWD during the first inspection interval. These ,
component supports shall be examined in accordance with Table IWF 2500-1.
Section XI, Paragraph IWF-2430 details the steps to be taken should additional examinations be required as a result of component support examinations requiring corrective actions per IWF-3000.
Licensee's Code Relief Reouest: Relief is requested from the IWF-2510 rules for component support selection and the IWF 2430 rules for additional examination.
26 l
m ._ . ._
. Licensee's Pronosed Alternative Examination: The Licensee proposes a sampling plan based on selection of a specified percentage of the nonexempt population of component supports; the exact percentage is determined by the Class of the component support.
Within the population, each individual component support is categorized'by a support type which identifies its function (e.g., anchor, mechanical snubber, rigid, variable).
The required number of component support selections shall be distributed within each class by system and type, proportional to the number of supports of each type within each system.
Licensee's Basis for Reauestina Relief: The Code does not provide specific guidance for component support selection and, therefore, user interpretation of the rules, as written, may not meet the intent of the Code. In addition, the rules for additional examinations are general and cannot effectively complement tho selection basL, nor target specific faibre modes.
Whi_le IWF-2510 implies that component supports be selected'for ,
examination, specific criteria for this selection has not been provided. Interpretation of these requirements is inconsistent and may vary by Code Category of the suppcrted component.
Also, the' current provisions in the Code for additional examinations are random and may or may not target a potential failure mode to a specific support population. Enhancement of the component support selection basis should also include a complementary plan for selection of additional examinations.
Evaluation: Review has been completed on Attachment 1 to Relief Request RR-09 titled " Class 1, 2, and 3 Piping Supports Sampling Plan." This document provides the specific details of 27
. the sampling plan to be appiled to Limerick Generating Station, Unit 2, with regard to the component supports selected for examination and the rules that apply when additional support examinations are required.
The ASME Code has recognized the need for a more definitive selection basis for component supports and has been looking at several different sampling plans for inclusion in a later edition of the Code. It is reported that the sampling plan discussed in the Licensee's submittal parallels the plan recently approved by the ASME Section XI Main Committee. This sampling plan is expected to be included in addenda to Section XI in the near future. Thus, the Licensee's proposed alternative will provide an cceeptable level of quality and safety. ,
Conclusions:
It is concluded the the Licensee's proposed alternative for the selection of Class 1, 2, and 3 supports to be examined provides an acceptable level of quality and safety '
as it meets or exceeds the intent of the Code requirements.
Therefore, pursuant to 10 CFR 50.55a(a)(3), it is rocommeaded that relief be granted as requested.
3.5.3.3 Recuest for Relief RR-12. Authorization Reauest for Use of ASME Code Casefs)
Code Reauirement: Code Cases are periodically published by ASME for the purpose of either clarifying the intent of the Code rules or for providing rules and regulations for circumstances which are not currently covered by existing Code rules but need to be addressed in a timely manner. Use of these nonmandatory Code Cases for inservice inspection is subject to NRC acceptance of the Code Case (s). USNRC Regulatory Guide 1.147, " Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1," lists those Code 28
. t. .
Cases that have been reviewed by the NRC and are generally acceptable for implementation in an ISI Program. Pursuant to 10 CFR 50.55a other Code Cases may be used provided specific I
authorization-is requested.
Licensee's Code Relief Reouest: The purpose of this relief request is to request authorization of the adoption of ASME Code Cases N-460, N 461, and N-479, not referenced in Regulatory Guide 1.147, for implementation in the Limerick Generating Station, Unit 2, ISI Program.
l Licensee's Prooosed Alternative Examination: The following Code Cases-are requested to be used in the Limerick Generating I l' ,
Station, Unit 2, ISI Program:
1 L (a) ASME Code Case N 460, " Alternative Examination Coverage for ;
Class 1 and Class 2 Welds;"
L 1
(b) ASME Code Case N 461, " Alternative Rules for Piping L
u Calibration Block Thickness;" and L (c) ASME Code Case N-479, " Boiling Water Reactor (BWR) Main l Steam System Hydrostatic Test."
j l-L Licensee's Basis for Reouestina Relief: ASME Code Case N-460 I will reduce the number of welds requirini relief requests due to incomplete examination coverage resulting from structural or l geometric interferences which reduce the examination volume or L area by less that.10%. . Additional relief is requested to extend the applicability of this Code Case-to Class 3 _
1 examination. Provided adequate examination documentation is )
l: prepared, the reduced coverages allowed for Class 1 and 2 welds can also be extended to Class 3 welds with no compromise of I Code intent.
I L ASME Code Case N-461 permits a plus or minus 25% tolerance for j '
L piping calibration block thicknesses. The minus 25% tolerance allowed by this Code Case is consistent with the requirements of ASME Section V, Article 5. The plus 25% tolerance could i
29 L
, slightly increase the examination sensitivity which would result in a more conservative examination. The adoption of this Code Case will provide for use of existing calibration blocks for a greater latitude of material thicknesses.
ASME Code Case N 479 permits hydrostatic testing Class 2 portions of the main steam system in BWRs in which the boundary valve between the Class 2 portion and the Class 1 portion is not capable of isolating the Class 2 portion from the Class 1 portion, at the Class I hydrostatic test pressure.
Evaluation: ASME Code Case N 460 provides for an alternative examination coverage for Class 1 and Class 2 welds. This code case was approved by the ASME Code Committee on July 27, 1988.
The code case was approved in Revision 8 of USNRC Regulatory Guide 1.147 (Reference 15) for generic use. Use of ASME Code Case N-460 is, therefore, acceptable for Class 1 and Class 2 welds. With regard to applying this code case to Class 3 welds, the code case is applicable for surface and volumetric examinations only and, since the Code does not require surface or volumetric examinations of Class 3 welds, cannot be applied to the Class 3 requirements.
ASME Code Case N 461 allows any calibration block thickness to be used that is within i25% of the pipe wall thickness to be examined. This code case was approved by the ASME Code Committee on November 30, 1988. The code case was approved in Revision 8 of NRC Regulatory Guide 1.147 for generic use with the following supplemental requirement: Thickness measurements and weld joint contour of the pipe / component must be known and used by the inspector who conducts the UT examination. Use of ASME Code Case N-461 is, therefore, acceptable with the condition stated above.
30
ASME Code Case N 479 permits the hydrostatic test pressure for -
the Class 2 portion.to meet the requirements of IWA-5000 and-IW8 5222. -This code case was approved by the ASME Code Committee on July 24, 1989. The NRC has not approved Code Case i N 479 for general usage.by acceptance in Regulatory Guide 1.147, Revision 8. Therefore, this Code Case must be reviewed by the NRC staff on a case by case basis.
Conclusions:
It is concluded that public health and safety will not be endangered by allowing 'ASME Code Cases N 460, N 461, and N-479 to be used at Limerick, Unit 2. Therefore, pursuant to 10 CFR 50.55a(a)(3), it is recommended that approval.to use these Code Cases be granted, with the exception of applying Code Case N-460 to Class 3 welds.
I M
2 s
31
i
- 4. CONCLUSION
^
Pursuant to 10 CFR 50.55a(g)(6) or,-alternatively, 10 CFR 50.55a(a)(3), it has been determined that certain Section XI required inservice examinations cannot be performed to the extent required by the Code. In' all cases for which relief is requested, except Requests for Relief RR ll and RR 12 (in part), the Licensee has demonstrated that specific Section XI requirements are impractical or that alternative examinations should be performed. For Requests for Relief RR 11 and RR-12 (in part), it is concluded that the Licensee has not provided information to support the determination that the Code requirement is impractical and that requiring the Licensee to comply with the Code requirement would not result in hardship.-
This technical evaluation has not identified any practical method by which the Licensee can meet all the specific inservice inspection requirements of Section XI of the ASME Code for the existing Limerick Generating Station, Unit 2, facility. Requiring compliance with all the exact Section XI required inspections would require redesign of a significant number of plant
-systems, sufficient replacement components to be obtained, installation of
- theLnew components, and a baseline examination of these components. Even after the' redesign efforts, complete compliance with the Section XI examination requirements probably could not be achieved. Therefore, it is concluded that the public interest is not served by imposing certain
. provisions of Section-XI of the ASME Code that have been determined to be impractical. Pursuant to 10 CFR 50.55a(g)(6), relief is allowed from these requirements which are impractical to implement, or alternatively, pursuant to 10 CFR 50.55a(a)(3), alternatives to the Code-required examinations may be granted provided that either-(i) the proposed alternative provides an acceptable level of quality and safety or that (ii) Code compliance would result _in hardship or unusual difficulty without a compensating increase in safety.- Relief may be granted only if granting the relief will not endanger
. life or property or the common defense and security and is otherwise in the public interest giving due consideration to the-burden upon the licensee
.that could result if the requirements were imposed on the facility.
32-
The development of new or improved examination techniques should continue to
-be monitored. As improvements.in these areas are achieved, the Licensee should incorporate these techniques in the ISI program plan examination requirements.
Based on the review of the Limerick Generating Station, Unit 2, First 10 Year Interval Inservice. Inspection Program, Revision 0, and the recommendations for granting relief from the ISI examination requirements that have been deterstned to be impractical, it is concluded that the Limerick Generating Station, Unit 2, First 10-Year Interval Inservice Inspection Program Plan, Revision 0, with the exception of Requests for Relief RR-il and RR 12 (in part), is acceptable and in compliance with
O 6
33
1
- 5. REFERENCES
- l. Code of Federal Regulations Title 10, Part 50,
- 2. Arierican Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI, Division 1:
1974 Edition through Sumer 1975 Addenda 1986 Edition
- 3. Limerick Generating Station, Unit 2, First 10 Year Interval Inservice Inspection Program, Revision 0, dated, February 20, 1990.
- 4. NUREG 0800, Standard Review Plans, Section 5.2.4, " Reactor Coolant Boundary Inservice Inspection and Testing," and Section 6.6, " Inservice Inspection of Class 2 and 3 Components," July 1981.
- 5. Generic Letter 88 01, "NRC Position on IGSCC in BWR Austenitic Stainless Steel Piping," January 25, 1988.
- 6. NUREG 0619, "BWR Feedwater Nozzle and Control Rod Drive Return Line Nozzle Cracking," November 1980.
7.IEBulletin8013."CrackinginCoreSpraySpargers," April 4I1980.
- 8. NUREG/CR 3052 (Closcout of IE Bulletin 80 07), "BWR Jet Pump Assembly Failure," November 1984.
- 9. NRC Mechanical Engineering Branch Technical Position MEB 3-1, July 1981,
" Protection Against Postulated Piping Failures in Fluid Systems Outside Containment" (NUREG 0800).
- 10. GE SIL No. 455, " Recommendation for Additional ISI of Alloy 182 Nozzle Weldments," Revision 1,-Supplement 1 Category 1, June 23, 1989.
- 11. Limerick Generating Station Finkl Safety Analysis Report (FSAR).
- 12. GE SIL No. 409, "Incore Dry Tube Cracks," Revision 1, Category 2, July 31, 1986,
- 13. CE SIL No. 420, " Inspection of Jet Pump Sensing Lines," Category 1, March 28, 1985.
- 14. Limerick Generating Station, Unit 2, Technical Specifications 3/4.7.4, Snubbers,
- 15. USNRC Regulatory Guide 1.147, " Inservice Inspection Code Case Acceptability, ASME Section XI Division 1," Revision 8, November 1990.
l 34
)
l g.o , u. vi w e a ta .iov6 ion ,co.. m o.,
.pg e,._
W:2 BIBLIOGRAPHIC DATA SHEET
,s...,..,,,,
.' 's. rn a *~o s* """ EGG MS 9028 Technical Evaluation Report on the First 10 Year Interval Inservice Inspection Program Plan: eari i. oar vius. :
Philadelphia Electric Company. o., ' - .
Limerick Generating Station, Unit 2 March l 19I..l Docket Number 50 353 u i~oacaast w vio FIN 06022 (Proj. 5)
- 5. av racaisi a rves o, apont Technical B.W. Brown, J.D. Mudlin voico cov o so ,.. . .. ,
u o gag gipa a r ion ~ *u a an o a oc a e u ,,, ,.c- .. s o .- es ., .- c.- . -. .,,,,,. , , .
EG&G Idaho, Inc.
P. O. Box 1625 Idaho Falls, 10 83415 2209
- e. ggo Aue4 riou - s4 s a~o co n n u ,,. ..c. ,, s . .,,,,,. ,, ..c o. ., ..m m .- c #
Haterials and Chemical Engineering Branch Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Connission Washington, D.C. 20555 -
- 10. $UPPQMENT AaY NOfl$
I1. A$$Ta ACI IJ00 ,uu .r eu, This report presents the results of the evaluation of the Limerick Generating Station,- Unit 2, First 10-Year Interval Inservice Inspection (ISI) Program, Revisien 0, submitted February 26, 1990, including the recuests for relief from the American Society of Mechanical Engineers (ASME) Boiler anc Pressure Vessel Code Section XI requirements that the Licensee has determined to be impractical. The Limerick Generating Station Unit 2, First 10-Year Interval ISI Program is evaluated in Section 2 of this report for (a) compliance with the appropriate edition / addenda of Section XI, (b) acceptability of examination sample, (c) correctness of the application of system or component examination exclusion criteria, and (d) compliance with IS!-related commitments identified during the Nuclear Regulatory Commission (NRC) review before granting an operating license. The requests for relief are evaluated in Section 3 of this report.
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, Mr. George J. Beck- Limerick Generating Station
.- Philadelphia Electric Company Units 1 & 2 CC:
J. W. Durham, Sr. Esquire Mr. Thomas Gerusky,-Director Sr. V,P. & General Counsel Bureau of Radiation Protection Philadelphia Electric Company PA Dept, of Environmental Resources 2301 Market Street P, 0.. Box 2063 Philadelphia, Pennsylvania 19101 Harrisburg, Pennsylvania 17120 Mr. Rod-Krich 52A-5 Single point of Contact Philadelphia Electric Company P, 0, Box 11800 955 Chesterbrook Boulevard Harrisburg, Pennsylvania 17iO8-188 Wayne, Pennsylvania 19087-5691 Mr. Graham M. Leitch, Vice President Mr. Garrett Edwards
-Limerick Generating Station Superintendent-Technical Post Office Box-A Limerick Generating Station
, Sanatoga,-Pennsylvania 19464 P, 0, Box A Sanatoga, Pennsylvania 19464 Mr. John Doering
. Plant Manager Mr. Gil J. Madsen.
Limerick Generating Station Reuglatory Engineer P.0,~ Box A Limerick Generating Station -
Sanatoga, Pennsylvania 19464 P. O. Box A Sanatoga, Pennsylvania 19464 Regional Administrator _
U.S. Nuclear Regulatory Commission Library Region I- .
US Nuclear Regulatory Commission 475 Allendale Road Region I King o_f Prussia, .PA 19406 475 Allendale Road Mr. Thomas Kenny -
Senior Resident Inspector US Nuclear Regulatory Connission -
c P. O. Box 596
[
Pottstown, Pennsylvania' 19464 i Mr. George A. Hunger j Project Manager Limerick Generating Station .
P, O. Box A g Sanatoga, Pennsylvania 19464 L
.Mr. Larry Hopkins-
- Superintendent-Operations .
Limerick Generating Station P. O. Box-A Sanatoga, Pennsylvania 19464
,