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MONTHYEARML0733408472007-12-13013 December 2007 Proposed Alternative Relief Request to Performance of System Pressure Test on Instrument Air Piping, Second Ten-Year Inservice Inspection Interval Project stage: Approval 2007-12-13
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Category:Letter
MONTHYEARIR 05000461/20230042024-02-0202 February 2024 Integrated Inspection Report 05000461/2023004 ML23361A1572024-01-24024 January 2024 Audit Plan in Support of Review of License Amendment Request Regarding Revision of Technical Specifications Related to Reactor Water Cleanup Isolation ML24004A0792024-01-18018 January 2024 Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0041 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting)) IR 05000461/20234022023-12-27027 December 2023 Security Baseline Inspection Report 05000461/2023402 ML23305A1402023-12-13013 December 2023 Units 1 & 2; Nine Mile Point, Unit 2; Peach Bottom, Units 2 & 3; and Quad Cities, Units 1 and 2 - Issuance of Amendments to Adopt Traveler TSTF-580 IR 05000461/20235012023-12-0505 December 2023 Emergency Preparedness Biennial Exercise Inspection Report 05000461/2023501 ML23284A2512023-11-22022 November 2023 Amendment No. 250 to Adopt TSTF-332 ML23317A1192023-11-10010 November 2023 Constellation Energy Generation, LLC - 2023 Annual Report - Guarantees of Payment of Deferred Premiums IR 05000461/20230032023-11-0808 November 2023 Integrated Inspection Report 05000461/2023003 ML22300A2212023-11-0202 November 2023 Preliminary Decommissioning Cost Estimate and Fuel Management Plan RS-23-097, Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans2023-10-12012 October 2023 Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans IR 05000461/20233012023-09-12012 September 2023 NRC Initial License Examination Report 05000461/2023301 RS-23-090, Annual Report of Emergency Core Cooling System Evaluation Model Changes and Errors for Clinton Power Station2023-09-0707 September 2023 Annual Report of Emergency Core Cooling System Evaluation Model Changes and Errors for Clinton Power Station RS-23-080, Constellation Energy Generation, LLC, Application to Revise Technical Specifications to Adopt TSTF-264-A, Revision 0, 3.3.9 and 3.3.10 - Delete Flux Monitors Specific Overlap Requirement SRs2023-08-30030 August 2023 Constellation Energy Generation, LLC, Application to Revise Technical Specifications to Adopt TSTF-264-A, Revision 0, 3.3.9 and 3.3.10 - Delete Flux Monitors Specific Overlap Requirement SRs IR 05000461/20234202023-08-29029 August 2023 Security Baseline Inspection Report 05000461/2023420 RS-23-081, Request for License Amendment to Revise Technical Specifications Related to Reactor Water Cleanup Isolation Instrumentation2023-08-21021 August 2023 Request for License Amendment to Revise Technical Specifications Related to Reactor Water Cleanup Isolation Instrumentation IR 05000461/20230022023-08-0404 August 2023 Integrated Inspection Report 05000461/2023002 RS-23-085, Supplemental Information Related to Request for Partial Site Release2023-08-0303 August 2023 Supplemental Information Related to Request for Partial Site Release ML23209A8102023-07-28028 July 2023 05000461; 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Nine Mile Point, 2; and Quad Cities, 1 & 2 - Correction of Amendment No. 193 Adoption of TSTF-306, Revision 2, Add Action to LCO 3.3.6.1 to Give Option to Isolate the Penetration EPID L-2022-LLA-0143 ML23114A2522023-04-28028 April 2023 Request to Use a Provision of a Later Edition of the ASME Boiler & Pressure Vessel Code, Section XI ML23081A0382023-04-25025 April 2023 County, 1 & 2; Nine Mile Point, 2; and Quad Cities, 1 & 2 - Issuance of Amendments to Adopt TSTF-306, Rev. 2, Add Action to LCO 3.3.6.1 to Give Option to Isolate the Penetration ML23110A3202023-04-21021 April 2023 Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes Inspection RS-23-049, Constellation Energy Generation, LLC, Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations2023-03-23023 March 2023 Constellation Energy Generation, LLC, Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations ML23061A1632023-03-0303 March 2023 Reassignment of the U.S. Nuclear Regulatory Commission Branch Chief in the Division of Operating Reactor Licensing for Plant Licensing Branch 3 IR 05000461/20220062023-03-0101 March 2023 Annual Assessment Letter for Clinton Power Station, Unit 1 (Report 05000461/2022006) RS-23-039, Request for License Amendment to Revise Technical Specifications Section 3.8.3, Diesel Fuel Oil, Lube Oil, and Starting Air2023-03-0101 March 2023 Request for License Amendment to Revise Technical Specifications Section 3.8.3, Diesel Fuel Oil, Lube Oil, and Starting Air ML23031A2972023-03-0101 March 2023 Issuance of Amendment No. 248 Adoption of TSTF-269, Revision 2 RS-23-045, Constellation Energy Generation, LLC Submittal of Fitness for Duty Performance Data Reports for 2022 Per 10 CFR 26.717(c) & 10 CFR 26.2032023-02-28028 February 2023 Constellation Energy Generation, LLC Submittal of Fitness for Duty Performance Data Reports for 2022 Per 10 CFR 26.717(c) & 10 CFR 26.203 ML23039A1852023-02-10010 February 2023 Integrated Inspection Report 05000461/2022004 07201046/2022001 RS-23-003, Constellation Energy Generation, LLC, Summary of Changes to Quality Assurance Topical Report, NO-AA-10, and Decommissioning Quality Assurance Program, NO-DC-102023-01-31031 January 2023 Constellation Energy Generation, LLC, Summary of Changes to Quality Assurance Topical Report, NO-AA-10, and Decommissioning Quality Assurance Program, NO-DC-10 IR 05000461/20220112023-01-27027 January 2023 Biennial Problem Identification and Resolution Inspection Report 05000461/2022011 RS-23-002, Application to Adopt TSTF-332, ECCS Response Time Testing2023-01-13013 January 2023 Application to Adopt TSTF-332, ECCS Response Time Testing ML23005A0682023-01-0505 January 2023 Notification of NRC Fire Protection Team Inspection Request for Information: Inspection Report 05000461/2023010 ML22341A6042022-12-0808 December 2022 Confirmation of Initial License Examination IR 05000461/20224022022-12-0606 December 2022 Security Baseline Inspection Report 05000461/2022402 RS-22-126, Constellation Energy Generation, LLC - Request to Use Provisions of a Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI2022-11-30030 November 2022 Constellation Energy Generation, LLC - Request to Use Provisions of a Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI 2024-02-02
[Table view] Category:Safety Evaluation
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Proposed Alternative for Repair of Water Level Instrumentation Partial Penetration Nozzles (Epids L-2021-LLR-0057 and L-2021-LLR-0058) ML22047A1272022-02-22022 February 2022 Relief from the Requirements of the American Society of Mechanical Engineers Code ML21347A0382022-01-13013 January 2022 Issuance of Amendments to Revise Reactor Coolant Leakage Requirements ML21306A0002021-12-21021 December 2021 License Amendment to Revise Degraded Voltage Relay Allowable Values ML21307A3422021-12-0707 December 2021 Issuance of Amendments to Adopt Reactor Pressure Vessel Water Inventory Control Enhancements (EPIDs L-2020-LLA-0253 and L-2020-LLA-0254) ML21277A2482021-11-16016 November 2021 Letter with Enclosure 4, Safety Evaluation for Transfer of Licenses and Draft Conforming License Amendments (Public Version) ML21280A0782021-10-27027 October 2021 Proposed Alternative to Use of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Case N-893 (Epids L-2020-LLR-0147 and L-2020-LLR-0148) ML21230A2062021-09-0303 September 2021 Proposed Alternative to Use ASME OM Code Case OMN-28 ML21216A2202021-08-0505 August 2021 Proposed Alternative to Eliminate Certain Documentation Requirements for Pressure Retaining Bolting ML21132A2882021-06-28028 June 2021 Issuance of Amendment No. 238, Adoption of Technical Specifications Task Force Traveler TSTF-505, Revision 2, Provide Risk Informed Extended Completion Times - RITSTF Initiative 4B ML21166A1682021-06-25025 June 2021 ML21090A1932021-05-19019 May 2021 Issuance of Amendment No. 237 Regarding Adoption of 10 CFR 50.69, Risk Informed Categorization and Treatment of Structures, Systems and Components of Nuclear Power Reactors ML21033A5302021-04-0101 April 2021 Issuance of Amendments to Adopt Technical Specifications Task Force TSTF-566, Revise Actions for Inoperable RHR Shutdown Cooling Subsystems ML21028A6732021-02-0303 February 2021 Request to Use a Provision of Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI (EPID L-2020-LLR-011 ML21005A0612021-01-14014 January 2021 Proposed Alternatives to Extend the Safety Relief Valve Testing Interval (EPID L-2020-LLR-0014 Through L-2020-LLR-0018) ML20287A1302020-11-0505 November 2020 Review of Quality Assurance Program Changes ML20268C2322020-11-0404 November 2020 Proposed Alternative I4R-06 to the Requirements of the ASME Code ML20266G3432020-10-14014 October 2020 Issuance of Amendment No. 235 Regarding Operation of the Emergency Auxiliary Reserve Transformer Load Tap Changer ML20269A2002020-09-30030 September 2020 Request to Use a Provision of Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI (EPID L2020-LLR-0117 ML20218A6602020-09-0202 September 2020 Proposed Alternative I4R-01 to the Requirements of the ASME Code ML20232A1882020-09-0101 September 2020 Proposed Alternative I4R-02 to the Requirements of the ASME Code ML20232A1712020-09-0101 September 2020 Request to Use Alternative Code Case OMN-26 ML20219A2022020-09-0101 September 2020 Proposed Alternative I4R-05 to the Requirements of the American Society of Mechanical Engineers Code ML20212L3902020-08-31031 August 2020 Proposed Alternative I4r-03 to the Requirements of the Asme Code (Epid L-2019-Llr-0114) ML20153A8042020-07-31031 July 2020 Co. - Issuance of Amendments Revising Emergency Action RA3 ML20141L6362020-07-10010 July 2020 Issuance of Amendments Based on TSTF-427,Allowance for Nontechnical Specification Barrier Degradation on Supported System Operability,Rev 2 ML20134H9402020-07-0808 July 2020 Issuance of Amendments Revising the High Radiation Area Administrative Controls ML20163A7172020-06-26026 June 2020 Proposed Alternative to the Requirements of the ASME Code ML20021A0702020-04-0606 April 2020 Issuance of Amendments to Delete License Conditions for Decommissioning Trusts ML19331A7252020-02-14014 February 2020 Issuance of Amendments Revising Emergency Action Levels ML20028E3992020-02-0404 February 2020 Proposed Alternative to Use ASME Code Case N-879 ML20010E8702020-01-27027 January 2020 Proposed Alternative to the Requirements of the ASME Code ML19238A3082019-09-30030 September 2019 Issuance of Amendment - Regarding Adoption of TSTF-476, Improved Banked Position Withdrawal Sequence Control Rod Insertion Process ML19269C5342019-09-27027 September 2019 Proposed Alternative to Use Encoded Phased Array Ultrasonic Examination Techniques ML19176A0332019-08-28028 August 2019 Issuance of Amendments to Adopt TSTF-564, Safety Limit MCPR ML19192A2442019-07-18018 July 2019 Proposed Alternative to Use ASME Code Cases N-878 and N-880 ML19109A0012019-06-12012 June 2019 Issuance of Amendment Regarding Recapture of Low-Power Testing Time ML19036A5862019-03-21021 March 2019 Issuance of Amendments to Revise the Emergency Response Organization Staffing Requirements ML18304A3652019-01-16016 January 2019 2. 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Text
December 13, 2007 Mr. Charles G. Pardee Chief Nuclear Officer and Senior Vice President Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
CLINTON POWER STATION, UNIT NO. 1 - PROPOSED ALTERNATIVE RELIEF REQUEST TO PERFORMANCE OF SYSTEM PRESSURE TEST ON INSTRUMENT AIR PIPING, SECOND TEN-YEAR INSERVICE INSPECTION INTERVAL (TAC NO. MD4896)
Dear Mr. Pardee:
By letter dated December 15, 2006, to the Nuclear Regulatory Commission (NRC), AmerGen Energy Company, LLC (the licensee) requested approval of an alternative to the requirements of the American Society of Mechanical Engineers (ASME) Code,Section XI, with regard to pressure testing of all Class 2 and Class 3 instrument air piping supplying all safety relief valves and both feedwater containment outboard isolation check valves, for the Clinton Power Station, Unit No. 1 (CPS). As an alternative to the examination requirement of the Code, CPS proposed to perform a pressure decay test in lieu of the visual examination during pressure testing of each safety relief valve and the feedwater isolation check valve accumulators, including all associated piping. The NRC staff has evaluated the licensees request for relief from the 1989 Edition, ASME Code,Section XI, and authorizes the proposed alternative pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(a)3(i) for the second 10-year inservice inspection interval of CPS. The NRC staffs review of the licensees analysis in support of its request for relief is documented in the enclosed safety evaluation.
Sincerely,
/RA/
Russell Gibbs, Chief Plant Licensing Branch III-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-461
Enclosure:
Safety Evaluation cc w/encl: See next page
ML073340847 OFFICE LPL3-2/PM LPL3-2/LA DCI/CSGB/BC OGC* LPL3-2/BC NAME SSands EWhitt AHiser MSmith RGibbs DATE 12/4/2007 12/4/2007 12/5/2007 12/12/2007 12/13/2007 Clinton Power Station, Unit No. 1 cc:
Corporate Distribution Exelon Generation Company, LLC via e-mail Clinton Distribution Exelon Generation Company, LLC via e-mail Clinton Senior Resident Inspector U.S. Nuclear Regulatory Commission via e-mail Illinois Emergency Management Agency Division of Disaster Assistance &
Preparedness via e-mail J. W. Blattner, Project Manager Sargent & Lundy Engineers via e-mail Chairman of DeWitt County c/o County Clerks Office DeWitt County Courthouse Clinton, IL 61727
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST OF THE SECOND 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM PROPOSED ALTERNATIVE TO SYSTEM PRESSURE TEST CLINTON POWER STATION, UNIT NO. 1 AMERGEN ENERGY COMPANY, LLC DOCKET NO. 50-461
1.0 INTRODUCTION
By letter to the Nuclear Regulatory Commission (NRC) dated December 15, 2006 (Agencywide Documents Access and Management System Accession No. ML063620098), AmerGen Energy Company, LLC, (the licensee) requested approval of an alternative to the requirement of the American Society of Mechanical Engineers (ASME) Code,Section XI, with regard to pressure testing of all Class 2 and Class 3 instrument air (IA) piping supplying all safety relief valves (SRV) and both feedwater containment outboard isolation check valves, for Clinton Power Station, Unit No. 1 (CPS). As an alternative to the examination requirement of the Code, CPS proposed to perform a pressure decay test in lieu of the visual examination during pressure testing of each SRV and the feedwater isolation check valve accumulators, including all associated piping as required under surveillance procedure, CPS 9061.11, that verifies the operability of SRV and check valves in the IA supply lines to all 16 SRVs and both feedwater containment outboard isolation check valves in accordance with the CPS inservice test program.
The NRC staff has reviewed the licensees proposed alternative pursuant to Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 55a(a)(3)(i), that the alternative would provide an acceptable level of quality and safety.
2.0 REGULATORY REQUIREMENTS Section 50.55a(g) of 10 CFR requires that inservice inspection (ISI) of ASME Code Class 1, 2, and 3 components be performed in accordance with Section XI of the ASME Code and applicable addenda, except where specific written relief has been granted by the NRC, pursuant to 10 CFR 50.55a(g)(6)(i). According to 10 CFR 50.55a(a)(3), alternatives to the requirements of paragraph 50.55a(g) may be used, when authorized by the NRC, if an applicant demonstrates that the proposed alternatives would provide an acceptable level of quality and safety, or if the specified requirement would result in hardship, or unusual difficulty without a compensating increase in the level of quality and safety.
Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, to the extent practical within the limitations of design, geometry, and materials of construction of the components. The Enclosure
regulations require that ISI 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),
12 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 second 10-year ISI interval is the 1989 Edition of the ASME Code,Section XI.
3.0 TECHNICAL EVALUATION
3.1 System/Component(s) for Which Relief is Requested:
Class 2 IA piping and components between containment isolation valves.
Class 3 IA piping and components supplying to all SRVs and both feedwater containment outboard isolation check valves.
3.2 ASME Code Requirements The 1989 Edition of the ASME Code,Section XI, paragraphs IWC-2500 and IWD-2500, state that components shall be examined and pressure tested as specified in Tables IWC-2500-1 and IWD-2500-1. Tables IWC-2500-1 and IWD-2500-1 require performance of VT-2 visual examination during system pressure tests.
3.2.1 Examination Categories:
Class 2 - C-H, All Pressure Retaining Components.
Class 3 - D-A, Systems in Support of Reactor Shutdown Function.
3.2.2 Item Numbers:
Class 2 - C7.30, Piping and Pressure Retaining Components and C7.70, Valves and Pressure Retaining Components.
Class 3 - D1.10, Pressure Retaining Components.
3.3 Licensees Request for Relief The licensee requested relief from performance of system pressure tests and VT-2 visual examination requirements specified in Tables IWC-2500-1 and IWD-2500-1 for all Class 2 and Class 3 IA piping supplying all SRVs and both feedwater containment outboard isolation check valves.
3.4 Basis for Requesting Relief Pursuant to 10 CFR 50.55a(a)(3), relief is requested on the basis that the proposed alternatives provide an acceptable level of quality and safety. Surveillance procedure CPS 9061.11, Instrument Air Check Valve Operability and Pipe Pressure Test, verifies the operability of SRV actuation and check valves in the IA supply lines to all 16 SRVs and both feedwater containment outboard isolation check valves. This surveillance test is performed for each individual SRV and both feedwater containment outboard isolation check valves as a requirement of the CPS inservice test (IST) program. One specific test this surveillance
performs, is a pressure decay test of the accumulators of the SRV and the feedwater containment outboard isolation check valves as well as associated piping and valves. The pressure decay test is performed by isolating and pressurizing these accumulators and associated piping to the nominal operating pressure. The decay in pressure is then monitored through calibrated pressure measuring instrumentation. If any pressure decay acceptance criterion of the procedure is exceeded, the surveillance identifies appropriate troubleshooting steps to perform including application of soap solution to locate leakage.
The pressure decay test performed as part of CPS 9061.11 identifies any degradation of the Class 2 and 3 IA supply piping to automatic depressurization system (ADS), the SRVs and the feedwater containment outboard isolation check valve accumulators and associated piping.
The volume tested by this surveillance encompasses all piping and components requiring testing under the ASME Code,Section XI for these portions of the IA system. This surveillance is performed on a greater frequency than that required per Tables IWC-2500-1 and IWD-2500-1 and the test pressure is consistent with the pressure requirements of both tables. Thus, the testing performed during this surveillance will provide the same level of quality and safety as that of the pressure testing and the VT-2 examination requirements of Tables IWC-2500-1 and IWD-2500-1.
The VT-2 visual examination described in Tables IWC-2500-1 and IWD-2500-1 and performed once per inspection period, would not provide an increase in safety, system reliability, or structural integrity. In addition, performance of a VT-2 visual examination would require applying a leak detection solution to a large amount of piping and components, many of which are in high radiation areas with limited access. The VT-2 examination would result in additional radiation exposure (estimated 2 roentgen equivalent man) and industrial safety challenges to personnel with no added benefit in the level of quality and safety. The visual examination would not be consistent with radiation exposure of practices As Low As Reasonably Achievable.
3.5 Licensees Proposed Alternate Examination As an alternative to the examination requirements of Tables IWC-2500-1 and IWD-2500-1, CPS will perform pressure decay testing on all Class 2 and Class 3 IA piping supplying all 16 SRVs and both feedwater containment outboard isolation check valves as required under CPS Inservice Test program outlined in Surveillance procedure CPS 9061.11.
4.0 STAFF EVALUATION The ADS utilizes selected SRVs for depressurization of the reactor. Each of the SRV utilized for automatic depressurization is equipped with an air accumulator and check valve arrangement. The accumulators assure that the valves can be held open following failure of the air supply to the accumulators.
The 1989 ASME Code,Section XI, requires a system leakage test of all pressure retaining components of the ADS and SRV accumulators including their associated piping once every 40 months, and a VT-2 visual examination is required to be conducted to detect evidence of leakage from the pressure retaining components. The ASME Code further states that the contained fluid in the system shall serve as the pressurizing medium. As an alternative to the
VT-2 visual examination requirements of the ASME Code, the licensee proposes to take credit for the technical specifications (TS) surveillance performed which states that each ADS SRV shall be determined operable automatically and manually on a 24-month frequency. In addition, the TS requires that these valves are to be surveillance tested in accordance with the IST program during each refueling outage. The licensees surveillance is governed by procedure CPS 9061.1, which verifies proper operation of the SRV IA supply system, actuator, solenoids, and if necessary, the proper valve stroke distance. This procedure requires performance of a pressure decay test by isolating and pressurizing the ADS and SRV accumulators including their associated piping to the nominal operating pressure and monitoring the pressure decay to ensure leak-tight integrity of the components. The decay in pressure of 1.5 psig within 60 to 108 minutes for larger volume components such as the accumulator headers for SRVs and 26 to 31 minutes for smaller volume components such as the accumulator header for the feedwater check valves as stated in the above surveillance procedure is an acceptable limit beyond which the pressure boundary is subjected to investigation for location of any leakage. The NRC staff considers this leakage criterion based on pressure decay to be an acceptable alternative to the ASME Code-required VT-2 visual examination of the pressure boundary. Even the ASME Code,Section XI, allows rate of pressure loss as an alternative to the VT-2 visual examination during system leakage test of buried components that are isolable by means of valves.
Nevertheless, assuming that the pressure decay provides an adequate assurance of a leak-tight integrity of the components during the surveillance, the proposed alternative offers further conservatism as reflected in the frequency of surveillance being once every 24 months as opposed to the ASME Code-required VT-2 visual examination frequency of once every 40 months. The NRC staff, believes that it is redundant to conduct a VT-2 visual examination in accordance with Tables IWC-2500-1 or IWD-2500-1 for Class 2 or Class 3 components of the ASME Code,Section XI, over and above the surveillance required under TS and the inservice tests to ensure leak-tight integrity of the pressure boundary of the ADS SRV accumulators and their associated piping. Therefore, the NRC staff has determined that the licensees proposed alternative would provide an acceptable level of quality and safety.
5.0 CONCLUSION
The NRC staff concludes that the licensees proposed alternative to perform pressure decay test for the ADS SRV accumulators and both feedwater containment outboard isolation check valves including associated piping every refueling outage in accordance with surveillance procedure CPS 9061.11, in lieu of the ASME Code-required VT-2 visual examination during each inspection period, would provide an acceptable level of quality and safety. Therefore, the proposed alternative is authorized pursuant to 10 CFR 50.55a(a)(3)(i) for CPS, for the second 10-year ISI interval. All other requirements of the ASME Code,Section XI for which relief has not been specifically requested remain applicable, including a third party review by the Authorized Nuclear Inservice Inspector.
Principal Contributor: P. Patnaik, NRR Date: December 13, 2007