ML050320250
| ML050320250 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 02/01/2005 |
| From: | Richard Laufer NRC/NRR/DLPM/LPD1 |
| To: | Shriver B Susquehanna |
| Guzman R | |
| References | |
| TAC MC1183, TAC MC1184, TAC MC1187, TAC MC1188, TAC MC1189, TAC MC1190 | |
| Download: ML050320250 (13) | |
Text
February 1, 2005 Mr. Bryce L. Shriver President-PPL Generation and Chief Nuclear Officer PPL Susquehanna, LLC 2 North Ninth Street Allentown, PA 18101
SUBJECT:
SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 - THIRD 10-YEAR INSERVICE INSPECTION (ISI) INTERVAL PROGRAM PLAN (TAC NOS. MC1183, MC1184, MC1187, MC1188, MC1189, MC1190)
Dear Mr. Shriver:
In a letter dated September 16, 2003, as supplemented by letters dated June 18, September 16, and November 3, 2004, PPL Susquehanna, LLC (PPL, the licensee), submitted 10 requests for relief (RRs) for Susquehanna Steam Electric Station, Units 1 and 2 (SSES 1 and 2), proposing alternatives to the requirements of Title 10 of the Code of Federal Regulations, Part 50, Section 55a (10 CFR 50.55a), concerning the requirements of the American Society of Mechanical Engineers, Boiler and Pressure Vessel Code (ASME Code),
for its third 10-year ISI program plan. The Nuclear Regulatory Commission (NRC) staff has reviewed PPLs regulatory and technical analysis in support of its requests for relief for 3RR-02, 3RR-04, and 3RR-06. The NRC completed its review of 3RR-03, 3RR-07, 3RR-08, 3RR-09, 3RR-10, and 3RR-11 in a safety evaluation (SE) dated September 24, 2004 (Agencywide Documents and Access Management System accession no. ML042680078). The remaining request for relief, 3RR-01, is currently under NRC review and will be issued with a separate SE.
PPL is currently in its third 10-year ISI interval which began on June 1, 2004, and will end on May 31, 2014. The ISI Code of record for the third 10-year interval for SSES 1 and 2 is the 1998 edition with the 2000 addenda of ASME Code,Section XI.
Based on the information provided by PPL, the NRC staff concludes that the ASME Code-required examinations discussed in 3RR-02 and 3RR-04 are impractical and that the licensees alternative examinations will provide reasonable assurance of the structural integrity of the subject welds. Therefore, relief is granted and the alternative imposed pursuant to 10 CFR50.55a(g)(6)(i) for the third 10-year ISI interval at SSES 1 and 2. The granting of relief requests 3RR-02 and 3RR-04 is authorized by law and 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.
In addition, the NRC staff concludes that PPLs proposed alternative for 3RR-06 provides an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(a)(3)(i), the NRC staff authorizes the proposed alternatives for 3RR-06 as described in PPLs letter dated September 16, 2003, for SSES 1 and 2 for the third 10-year ISI interval.
B. Shriver If you have any questions, please contact Rich Guzman, at (301) 415-1030.
Sincerely,
/RA/
Richard J. Laufer, Chief, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-387 and 50-388
Enclosure:
Safety Evaluation cc w/encl: See next page
B. Shriver If you have any questions, please contact Rich Guzman, at (301) 415-1030.
Sincerely,
/RA/
Richard J. Laufer, Chief, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-387 and 50-388
Enclosure:
Safety Evaluation cc w/encl: See next page DISTRIBUTION:
PUBLIC PDI-1 RF RLaufer TChan ACRS RGuzman MOBrien GHill (4) OGC GMatakas, Rgn-1 RDavis CMiller, EDO, RGN-I DLPM DPR RDavis ACCESSION NO.: ML050320250 *SE provided. No major changes made.
OFFICE PDI-1/PM PDI-2/LA EMEB/SC* OGC PDI-1/SC NAME RGuzman MO'Brien TChan MYoung RLaufer DATE 1/11/05 1/13/05 12/7/04 SE 1/29/05 1/31/05 DTD OFFICIAL RECORD COPY
Susquehanna Steam Electric Station Units 1 and 2 cc:
Britt T. McKinney Michael H. Crowthers Vice President - Nuclear Site Operations Supervising Engineer PPL Susquehanna, LLC Nuclear Regulatory Affairs 769 Salem Blvd., NUCSB3 PPL Susquehanna, LLC Berwick, PA 18603-0467 Two North Ninth Street, GENPL4 Allentown, PA 18101-1179 Robert A. Saccone Vice President - Nuclear Operations Dale F. Roth PPL Susquehanna, LLC Manager - Quality Assurance 769 Salem Blvd., NUCSB3 PPL Susquehanna, LLC Berwick, PA 18603-0467 769 Salem Blvd., NUCSB2 Berwick, PA 18603-0467 Aloysius J. Wrape, III General Manager - Performance Luis A. Ramos Improvement and Oversight Community Relations Manager, PPL Susquehanna, LLC Susquehanna Two North Ninth Street, GENPL4 PPL Susquehanna, LLC Allentown, PA 18101-1179 634 Salem Blvd., SSO Berwick, PA 18603-0467 Terry L. Harpster General Manager - Plant Support Bryan A. Snapp, Esq PPL Susquehanna, LLC Assoc. General Counsel 769 Salem Blvd., NUCSA4 PPL Services Corporation Berwick, PA 18603-0467 Two North Ninth Street, GENTW3 Allentown, PA 18101-1179 Gregory F. Ruppert General Manager - Nuclear Engineering Supervisor - Document Control Services PPL Susquehanna, LLC PPL Susquehanna, LLC 769 Salem Blvd., NUCSB3 Two North Ninth Street, GENPL4 Berwick, PA 18603-0467 Allentown, PA 18101-1179 Rocco R. Sgarro Richard W. Osborne Manager - Nuclear Regulatory Affairs Allegheny Electric Cooperative, Inc.
PPL Susquehanna, LLC 212 Locust Street Two North Ninth Street, GENPL4 P.O. Box 1266 Allentown, PA 18101-1179 Harrisburg, PA 17108-1266 Walter E. Morrissey Director - Bureau of Radiation Protection Supervising Engineer Pennsylvania Department of Nuclear Regulatory Affairs Environmental Protection PPL Susquehanna, LLC P.O. Box 8469 769 Salem Blvd., NUCSA4 Harrisburg, PA 17105-8469 Berwick, PA 18603-0467
Susquehanna Steam Electric Station Units 1 and 2 cc:
Senior Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 35, NUCSA4 Berwick, PA 18603-0035 Regional Administrator, Region 1 U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Board of Supervisors Salem Township P.O. Box 405 Berwick, PA 18603-0035 Dr. Judith Johnsrud National Energy Committee Sierra Club 443 Orlando Avenue State College, PA 16803
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO RELIEF REQUEST NOS. 3RR-02, 3RR-04, AND 3RR-06 FOR THE INSERVICE INSPECTION PROGRAM PLAN FOR THE THIRD 10-YEAR INSPECTION INTERVAL PER THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS BOILER AND PRESSURE VESSEL CODE, SECTION XI, REQUIREMENTS PPL SUSQUEHANNA, LLC ALLEGHENY ELECTRIC COOPERATIVE, INC.
SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 DOCKET NOS. 50-387 AND 50-388
1.0 INTRODUCTION
In a letter dated September 16, 2003, as supplemented by letters dated June 18, September 16, and November 3, 2004, PPL Susquehanna, LLC (PPL, the licensee), submitted 10 requests for relief (RRs) for Susquehanna Steam Electric Station, Units 1 and 2 (SSES 1 and 2), proposing alternatives to the requirements of Title 10 of the Code of Federal Regulations, Part 50, Section 55a (10 CFR 50.55a), concerning the requirements of the American Society of Mechanical Engineers, Boiler and Pressure Vessel Code (ASME Code),
for its third 10-year inservice inspection (ISI) program plan. The Nuclear Regulatory Commission (NRC) staff has reviewed PPLs regulatory and technical analysis in support of its requests for relief for 3RR-02, 3RR-04, and 3RR-06. The NRC completed its review of 3RR-03, 3RR-07, 3RR-08, 3RR-09, 3RR-10, and 3RR-11 in a safety evaluation (SE) dated September 24, 2004 (Agencywide Documents and Access Management System Accession No. ML042680078). The remaining request for relief, 3RR-01, is currently under NRC review and will be issued with a separate SE.
The first relief, 3RR-02, proposes an alternative to examination requirements for residual heat removal (RHR) and core spray (CS) pumps, 3RR-04 proposes an alternative to examination of pressure retaining welds in control rod housings, and 3RR-06 proposes an alternative to evaluation requirements for temporary acceptance of flaws.
2.0 REGULATORY EVALUATION
The ISI of the ASME Code, Class 1, 2, and 3 components is to be performed in accordance with Section XI of the ASME Code and applicable edition and addenda as required by Title 10 if the Code of Federal Regulations, Part 50, Section 55a (10 CFR 50.55a(g)), except where specific written relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i).
Section 50.55a(a)(3) states, in part, that alternatives to the requirements of paragraph (g) may be used, when authorized by the NRC, if the licensee demonstrates that: (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 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 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) twelve months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein. The ISI Code of record for the third 10-year interval for SSES 1 and 2, is the 1998 edition through the 2000 addenda. The components (including supports) may meet the requirements set forth in subsequent editions and addenda of the ASME Code incorporated by reference in 10 CFR 50.55a(b) subject to the limitations and modifications listed therein and subject to Commission approval.
3.0 TECHNICAL EVALUATION
3.1 3RR-02 Code Requirement and Component ASME Code,Section XI, 1998 edition, 2000 addenda, Table IWC-2500-1, Examination Category C-G, Item Number C6.10, Pump Casing Welds, requires a surface examination on 100 percent of the welds for each 10-year ISI interval in all pump casings as defined by Figure IWC-2500-8. In the case of multiple pumps of similar design, size, function, and service in a system, the examination of only one pump among each group of multiple pumps is required.
The examination may be conducted from the inside or outside surface.
PPLs Basis for Relief PPL requested relief from the ASME Code-required 100 percent surface examination coverage of unaccessible pump casing welds as shown in Figure 3RR-02.1, Rev. 1 in Attachment B to Enclosure 2 of PPLs June 18, 2004 letter, for eight RHR pumps, four per unit, and eight CS pumps, four per unit. PPL requested that relief be granted for the inservice examination to be performed during the third 10-year ISI interval. The relief request pertains to 9 of 17 RHR pump-casing welds (on one pump) per unit and 9 of 16 CS pump-casing welds (on one pump) per unit.
PPL proposes the following in lieu of performing surface or volumetric examinations on all pump-casing welds (on one-pump-per-system per Unit) in accordance with the ASME Code:
For RHR and Core Spray pump casing welds, a surface or volumetric examination will be performed on the welds or portion of welds that are accessible. During normal
maintenance activities, should a weld or portion of a weld become completely accessible (no restrictions), this weld or portion of this weld will have a surface or volumetric examination performed. Should access to these welds or portions [of these welds] be restricted so that examiners cannot adequately perform a surface or volumetric examination, a visual (VT-1) or remote visual (VT-1) examination will be performed, to the extent practical, on these welds.
PPL states that the specified welds that it has identified in its request are not accessible for inspection due to plant configuration. Figure 3RR-02.1, Rev. 1 of PPLs June 18, 2004, letter shows the locations of the welds for which the licensee seeks relief. The welds in question are either inside the pump or embedded in concrete, and therefore, impractical to examine.
Examination would only be possible through destructive methods or possibly some limited coverage could be achieved from the internal surface depending upon how much disassembly of the pumps could be performed. PPL feels that disassembly of the pumps for the sole purpose of examination is a major effort that could result in damage to the pumps with only very minimal exam coverage being accessible based on past experience. PPL states that the code required examinations are impractical, and therefore, seeks relief pursuant to 10 CFR 50.55a(g)(5)(iii).
In response to additional information requested by the NRC staff, PPL indicated that previous inspections of the aforementioned pump-casing welds were completed by surface examination and VT-1 examination. PPL provided a list of welds that have been previously inspected; the inspection results show that no relevant indications were discovered in any RHR or CS pumps.
NRC Staffs Evaluation The NRC staff has reviewed PPLs information concerning 3RR-02 for the third 10-year ISI interval at SSES 1 and 2 pertaining to the pump-casing welds for eight RHR pumps (four per unit) and eight CS (four per Unit). The ASME Code requires that these welds receive a 100-percent surface examination of either the inside or outside surface during each inspection interval. The welds for which relief is being requested are inaccessible which prevents an ASME Code-required surface examination from being performed. For a complete inspection on the outside surface of the welds, redesign and modification of the plant layout for relocation of these pumps would be necessary because the subject welds on the outside of the pumps are encased in concrete. The inaccessibility of the welds due to pump design and plant configuration makes surface examination from the outside impractical.
Surface examination from the inside would require disassembly of the pumps and would only provide a limited inspection because of pump configuration. A VT-1 or remote VT-1 of the inside diameter of the pump-casing welds, if the pump is disassembled for maintenance, and the ASME Code required examination of the welds that are accessible, will provide an acceptable alternative to the required ASME Code examination techniques, considering the accessability and configuration of the internal weld surfaces. A VT-1 or remote VT-1 examination should be adequate to detect service induced flaws. The lack of recordable indications on the RHR or CS pumps during previous inspections provides additional assurance of the structural integrity of the pumps. In its November 3, 2004 letter, PPL attempted to clarify its previous response to a question from the staff regarding extent and methods of its proposed alternative examination. PPL indicates that areas that become accessible for the ASME
Code-required surface examination will receive a surface examination or a volumetric examination. Although the ASME Code requires a surface examination, a volumetric examination is considered more robust because it can detect defects in the entire weld volume in comparison to a surface examination which will only detect surface breaking flaws on the side of the weld that is inspected.
The requirement to perform examinations in accordance with the ASME Code is impractical due to the inaccessibility of the subject welds. The licensees alternative will provide reasonable assurance of structural integrity of the pump-casing welds referenced in PPLs request.
Conclusion The NRC staff has reviewed PPLs submittal and concludes that compliance with the ASME Code coverage requirements for the pump-casing welds identified in PPLs relief request 3RR-02, is impractical. The NRC staff has determined that if the ASME Code requirements were to be imposed on the licensee, the pumps must be redesigned which would impose a burden on the licensee. The NRC staff has further determined that the proposed alternative to perform a surface or volumetric examination of the accessible welds to the extent possible at the frequency described in IWC-2500 and a VT-1 or remote VT-1 of the pump-casing welds that become accessible as a result of maintenance, will provide reasonable assurance of the structural integrity of the subject welds. Therefore, relief is granted from the ASME Code requirement and the alternative imposed pursuant to 10 CFR 50.55a(g)(6)(i), for the third ISI interval for SSES 1 and 2. All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.
3.2 3RR-04 Code Requirement and Component ASME Code,Section XI, 1998 edition, 2000 addenda, Table IWB-2500-1, Examination Category B-O, Item Number B14.10, welds in control rod drive (CRD) housing, require volumetric or surface examination on 10 percent of peripheral CRD housing welds for each 10-year ISI interval. SSES 1 and 2 have 185 CRD housings each. SSES 1 and 2 have 40 peripheral housings each; therefore, the subject examinations are required of the pressure retaining welds of 4 (peripheral) housings (per unit) during the third inspection interval.
PPLs Basis for Relief PPL proposes to perform a Visual (VT-1) of the housing-to-flange welds of 4 (peripheral) housings (per unit) during the third inspection interval in lieu of the ASME Code-required surface or volumetric examination. PPL states that it will also be performing periodic VT-2 visual examination of the subject welds during Class 1 system pressure testing. If sufficient access is not available to perform a visual VT-1, a remote VT-1 examination to the extent practical will be performed.
PPL states that it is requesting relief from the ASME Code-required examination of the CRD housing-to-flange welds due to numerous plant design obstructions. The CRD position indicator probes, CRD shoot out steel, and CRD flange shields severely limit access to the
housing-to-flange welds. PPL also states that the high radiation doses in this area make it impractical to attempt to perform limited examinations in the face of these obstacles.
The remaining housing weld is without obstructions and can be completely examined. PPL believes that a VT-1 or remote VT-1 to the extent practical coupled with the periodic VT-2 visual examination during Class 1 system pressure testing will provide reasonable assurance of the pressure integrity of the housing-to-flange welds. PPL states that the ASME Code-required examinations are impractical, and therefore, seeks relief pursuant to 10 CFR 50.55a(g)(5)(iii).
NRC Staffs Evaluation The NRC staff has reviewed PPLs information concerning 3RR-04 for the third 10-year ISI interval at SSES 1 and 2, pertaining to the CRD housing, housing-to-flange welds. Each unit contains 185 CRDs. Each CRD housing contains two pressure-retaining welds, the housing-to-flange weld and the housing tube A-to-housing-tube-B weld. Forty of the 185 housings are on the peripheral of the lower vessel head. The ASME Code requires that 10 percent of the welds (4) on the outer peripheral of each unit receive a surface of volumetric examination in accordance with Table IWB-2500-1. PPL provided drawings, photographs and a written description of the lower reactor vessel head area. Based on this information, the NRC staff concludes that the housing-to-flange welds referenced in the relief request are not accessible for the ASME Code required inspections due to plant configuration. The NRC staff inquired about the method and extent of examinations of the subject welds during past ISI intervals. PPL responded that relief from inspection of the peripheral CRD housing-to-flange welds was granted prior to the start of the second interval in 2RR-8, and that these welds were not inspected through the required ASME Code,Section XI examinations (surface or volumetric). Rather, they were inspected as part of the vessel VT-2 examination prior to startup at the end of each refueling outage. The NRC staff considers PPLs current proposal to be more robust than performing only a VT-2 during Class 1 system pressure testing. PPLs alternative of performing a VT-1, or if necessary a remote VT-1, to the extent practical and a periodic VT-2 visual examination during Class 1 system pressure testing, will provide reasonable assurance of the pressure integrity of the housing to flange welds.
Conclusion The NRC staff has reviewed PPLs submittal and concludes that compliance with the ASME Code requirements for the CRD housing, housing-to-flange welds identified in PPLs 3RR-04, is impractical due to inaccessibility. If the ASME Code requirements were to be imposed, the licensee would be required to redesign CRDs and surrounding obstructions and would result in a burden on the licensee. The proposed alternative to perform a VT-1 of the housing-to-flange welds or a remote VT-1 to the extent practical, in lieu of a surface examination described in IWB-2500-1, coupled with the periodic VT-2 visual examination during Class 1 system pressure testing and lack of known degradation of CRD welds in the BWR fleet, will provide reasonable assurance of structural integrity of the subject welds. Therefore, relief is granted from the ASME Code requirement and the alternative imposed pursuant to 10 CFR 50.55a(g)(6)(i), for the third ISI interval for SSES 1 and 2.
All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.
3.3 3RR-06 Code Requirement and Component ASME Code,Section XI, IWC-3122.3, Acceptance by Analytical Evaluation, states, in part, that a component whose examination detects flaws that exceed the acceptance standards of Table IWC-3410-1 is acceptable for continued service without a repair/replacement activity if an analytical evaluation, as described in IWC-3600, meets the acceptance criteria of IWC-3600.
IWC-3610 states that acceptance criteria are in the course of preparation and that in the interim, the criteria of IWB-3610 may be applied.
PPLs Basis for Relief PPL requested relief, in accordance with 10 CFR 50.55a(a)(3)(i), to use ASME Code,Section XI, Code Case 513-1. When using Code Case 513-1, PPL committed to the following conditions:
When using analytical evaluation as the method of acceptance for flaws in moderate energy Class 2 or 3 piping, SSES will follow the provisions of Code Case 513-1 without performing a repair/replacement activity. This acceptance will be temporary and will remain in affect for a limited time, not exceeding the time to the next scheduled outage.
SSES may implement this method or one of the other methods contained in ASME Section XI to accept detected flaws; however, in no case will the temporary evaluation process be applied to:
(a) components other than pipe or tube, (b) leakage through a gasket, (c) threaded connections with nonstructural seal welds for leakage prevention, or (d) degraded socket welds.
When applying the methods of Code Case 513-1, the specific safety factors contained in Paragraph 4.0 of the Case will be satisfied. These conditions are consistent with those contained in 10CFR50.55a(b)(2)(xiii) regarding the use of Code Case 513.
Pursuant to 10 CFR 50.55a(a)(3)(i), PPL requested relief on the basis that its proposed alternative will provide an acceptable level of quality and safety. ASME Code,Section XI, Code Case 513 is conditionally approved for use in Revision 13 of Regulatory Guide (RG) 1.147; however, this ASME Code Case is not applicable to the 2000 addenda which is the applicable code of record for the third inspection interval. Code Case 513-1 has since been issued in Supplement 11 of the 1998 edition and is currently applicable through the 2001 edition. This revision of the Code Case is not yet approved for use by the NRC. Code Case 513-1 revises the base case to expand the temporary acceptance methodology from Class 3 moderate energy piping to Class 2 and 3 moderate energy piping. Both cases provide requirements which may be followed for temporary acceptance of flaws in ASME Code,Section III, ANSI B31.1, and ANSI B31.7 piping designated as Class 2 or 3. This acceptance is limited to moderate energy piping defined as piping whose maximum operating temperature does not
exceed 200 EF and whose maximum operating pressure does not exceed 275 psig. The provisions of the Code Case demonstrate the integrity of the item containing the flaw for a limited period of time until appropriate repair/replacement or additional examination activities can be performed.
NRC Staffs Evaluation PPL seeks relief from the requirements of IWC-3122.3 which states that a component whose volumetric or surface examination detects flaws may be acceptable for continued service without a repair/replacement activity if an analytical evaluation is performed in accordance with IWC-3600. As an alternative, PPL proposed to use the provisions of Code Case 513-1 to evaluate the acceptability of flaws without performing a repair/replacement activity. This acceptance of flaws using the provisions of Code Case 513-1 will be temporary and will remain in affect for a limited time, not exceeding the time to the next scheduled outage. The proposed relief is sought for the third 10-year ISI interval. The SSES 1 and 2 third 10-year ISI program plan meets the requirements of ASME Code,Section XI, 1998 edition through the 2000 addenda.
The NRC staff finds the proposed alternative will provide an acceptable level of quality and safety. This finding is based on the following considerations:
(1) ASME Code,Section XI, Code Case 513 is conditionally approved for use in Revision 13 of the NRC RG 1.147. PPLs proposed alternative satisfies the conditions stated in Revision 13 to RG 1.147 for Code Case 513.
(2) Code Case 513-1 expands the temporary acceptance methodology from Class 3 moderate energy piping to Class 2 and 3 moderate energy piping. Both cases provide requirements which may be followed for temporary acceptance of flaws in ASME Code,Section III, ANSI B31.1, and ANSI B31.7 piping designated as Class 2 or 3. The conditions stated in Revision 13 to RG 1.147 for Case 513 apply also for Case 513-1.
Since the issuance of Revision 13 to RG 1.147, the staff has determined that the analytical procedures specified in Case 513 to evaluate degraded Class 3 piping can be applied to Class 2 moderate energy piping for limited duration, not exceeding the time to the next scheduled outage.
(3) Both Cases apply only to moderate energy piping defined as piping whose maximum operating temperature does not exceed 200 EF and whose maximum operating pressure does not exceed 275 psig.
(4) The provisions of both ASME Code Cases provide for demonstration of structural integrity of an item containing flaws for a limited period of time until appropriate repair/replacement can be performed.
Conclusion Based on the information provided in PPLs submittal, the NRC staff has determined that the proposed alternative, as described in 3RR-06, provides an acceptable level of quality and safety. This is based on the fact that PPL will use the provisions specified in ASME
Code Case 513-1. The staff has determined that the analytical procedures specified in Code Case 513 can be used to evaluate the structural integrity of degraded Class 2 and Class 3 moderate energy piping for limited duration, not exceeding the time to the next scheduled outage. The NRC staff has conditionally approved Code Case 513 for use in Revision 13 of the NRC RG 1.147. PPLs proposed alternative satisfies the conditions stated in Revision 13 to RG 1.147. The NRC staff concludes that PPL has proposed an acceptable alternative to the requirements of ASME Code,Section XI; and, therefore, 3RR-06 is authorized pursuant to 10 CFR 50.55a(a)(3)(i) for the third 10-year ISI intervals at SSES 1 and 2.
4.0 CONCLUSION
S Based on the above evaluations, the NRC staff concludes that the ASME Code-required examinations discussed in 3RR-02 and 3RR-04 are impractical and that the licensees alternative examinations will provide reasonable assurance of the structural integrity of the subject welds. Therefore, relief is granted and the alternative imposed pursuant to 10 CFR50.55a(g)(6)(i) for the third 10-year ISI interval at SSES 1 and 2. The granting of relief requests 3RR-02 and 3RR-04 is authorized by law and 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.
For 3RR-06, the NRC staff concludes that the proposed alternative provides an acceptable level of quality and safety, and is, therefore, authorized pursuant to 10 CFR 50.55a(a)(3)(i). All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.
Principal Contributors: R. Davis Date: February 1, 2005