Letter Sequence Other |
---|
|
|
MONTHYEARML0230204982002-10-29029 October 2002 Attachment to 10/29/2002 Letter - ONS 1EOC-20 Steam Generator Inspection Plan, ONS-1B Tube Server of Tube 78-124 Project stage: Other ML0230200102002-10-29029 October 2002 Summary of Conference Call with Duke Energy 2002 Steam Generator Results Project stage: Other 2002-10-29
[Table View] |
|
---|
Category:Letter
MONTHYEARML23304A1422024-02-0101 February 2024 Issuance of Environmental Scoping Summary Report Associated with the U.S. Nuclear Regulatory Commission Staffs Review of the Oconee Nuclear Station, Units 1, 2, & 3, Subsequent License Renewal Application ML24005A2492024-01-24024 January 2024 Exemption from Select Requirements of 10 CFR Part 73 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting) IR 05000269/20243012024-01-11011 January 2024 Notification of Licensed Operator Initial Examination 05000269/2024301, 05000270/2024301, and 05000287/2024301 ML23331A7982023-12-14014 December 2023 Review of the Fall 2022 Steam Generator Tube Inspection Report (01R32) ML23262A9672023-12-13013 December 2023 Alternative to Use RR-22-0174, Risk-Informed Categorization and Treatment for Repair/Replacement Activities in Class 2 and 3 Systems Section XI, Division 1 ML23317A3462023-11-14014 November 2023 Duke Fleet - Correction Letter to License Amendment Nos. 312 & 340 Issuance of Amendments Regarding the Adoption of Technical Specifications Task Force Traveler TSTF-554, Revision 1 IR 05000269/20230032023-11-14014 November 2023 Integrated Inspection Report 05000269/2023003, 05000270/2023003, and 05000287/2023003; and IR 07200040/2023001; and Exercise of Enforcement Discretion ML23219A1402023-10-10010 October 2023 Audit Report Proposed Alternative to Use ASME Code Case N-752, Risk Informed Categorization and Treatment for Repair/Replacement Activities in Class 2 and 3 Systems XI, Division 1 ML23269A1102023-10-0606 October 2023 Letter to Steven Snider-Revised Schedule for the Environmental Review of the Oconee Nuclear Station, Unit 1, 2, and 3, Subsequent License Renewal Application ML23256A0882023-09-25025 September 2023 Issuance of Alternative to Steam Generator Welds ML23195A0782023-08-29029 August 2023 Issuance of Amendments Regarding the Adoption of Technical Specifications Task Force Traveler TSTF-554, Revision 1 IR 05000269/20230112023-08-25025 August 2023 Comprehensive Engineering Team Inspection Report 05000269/2023011 and 05000270/2023011 and 05000287/2023011 IR 05000269/20230052023-08-25025 August 2023 Updated Inspection Plan for Oconee Nuclear Station Units 1, 2 and 3 (Report 05000269/2023005, 05000270/2023005, and 05000287/2023005) IR 05000269/20230022023-07-28028 July 2023 Integrated Inspection Report 05000269/2023002, 05000270/2023002 and 05000287/2023002 ML23208A0972023-07-27027 July 2023 Subsequent License Renewal List of Threatened and Endangered Species That May Occur in Your Proposed Project Location or May Be Affected IR 05000269/20230102023-07-19019 July 2023 Biennial Problem Identification and Resolution Inspection Report 05000269/2023010 and 05000270/2023010 and 05000287/2023010 and Notice of Violation ML23178A0682023-07-0303 July 2023 Audit Plan Proposed Alternative to Use ASME Code Case N-752, Risk-Informed Categorization and Treatment for Repair/Replacement Activities in Class 2 & 3 Systems Section XI, Division 1 ML23132A2392023-06-0101 June 2023 Summary of the April 2023 Remote Environmental Audit Related to the Review of the Subsequent License Renewal Application ML23144A0192023-05-25025 May 2023 Review of the Spring 2022 Steam Generator Tube Inspection Report (O3R31) IR 05000269/20230012023-05-12012 May 2023 Integrated Inspection Report 05000269/2023001 and 05000270/2023001 and 05000287/2023001 ML23121A0552023-05-0303 May 2023 Acknowledgement of Withdrawal Request to Revise TS 5.5.2 Containment Leakage Rate Testing Program ML23118A0762023-05-0101 May 2023 Approval for Use of Specific Provision of a Later Edition of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI ML23117A0432023-04-20020 April 2023 Framatome, Inc., Part 21 Notification of Existence of a Defect ML23075A0732023-04-0505 April 2023 License Renewal Regulatory Audit Regarding the Environmental Review of the Subsequent License Renewal Application Supplement (EPID Number L-2021-SLE-0002) ML23045A1332023-03-15015 March 2023 Request for Scoping Comments Concerning the Supplemental Environmental Review of Oconee Nuclear Station, Units 1, 2, and 3, Subsequent License Renewal Application - Achp Letter ML23045A1402023-03-15015 March 2023 Request for Scoping Comments Concerning the Supplemental Environmental Review of Oconee Nuclear Station, Units 1, 2, and 3, Subsequent License Renewal Application - Shpo Letter ML23045A1432023-03-15015 March 2023 Request for Scoping Comments Concerning the Supplemental Environmental Review of Oconee Nuclear Station, Units 1, 2, and 3, Subsequent License Renewal Application - State Tribe Letter ML22332A4932023-03-10010 March 2023 William States Lee III 1 and 2 - Issuance of Amendments Regarding the Relocation of the Emergency Operations Facility ML23069A1102023-03-10010 March 2023 Notification of Inspection and Request for Information for NRC Problem Identification and Resolution Inspection ML23061A1772023-03-0303 March 2023 Notification of Oconee Nuclear Station Comprehensive Engineering Team Inspection - NRC Inspection Report 05000269/2023011, 05000270/2023011 and 05000287/2023011 IR 05000269/20220062023-03-0101 March 2023 Annual Assessment Letter for Oconee Nuclear Nuclear Station, Units 1, 2 and 3 (NRC Inspection Report 05000269/2022006, 05000270/2022006, and 05000287/2022006) ML23039A1632023-02-0808 February 2023 Requalification Program Inspection ML23037A0772023-02-0606 February 2023 402 Cyber Notification and RFI Letter Final IR 05000269/20220042023-02-0202 February 2023 Integrated Inspection Report 05000269 2022004 and 05000270/2022004 and 05000287/2022004 ML22363A3942023-01-12012 January 2023 Subsequent License Renewal Environmental Report Supplement - Proposed Review Schedule ML22356A0512022-12-14014 December 2022 Curtiss-Wright Nuclear Division, Letter Regarding Potential Efect in a Configuration of the 11/2 Inch Quick Disconnect Connector Cable Assemblies Supplied to Duke Energy (See Attached Spreadsheet) for a Total of 460 of Connectors Only Suppl ML22321A0492022-12-0808 December 2022 Issuance of Amendment Nos. 426, 428 and 427, Additional Mode Change Limitations Applicable to the Adoption of TSTF- 359, Revision 9, Increase Flexibility in Mode Restraints ML22329A1042022-11-29029 November 2022 Review of the Fall 2021 Steam Generator Tube Inspection Report ML22321A1582022-11-22022 November 2022 Summary of Conference Call Regarding the Fall 2022 Steam Generator Tube Inspections ML22096A0032022-11-18018 November 2022 McGuire Nuclear Station and Shearon Harris Nuclear Power Plant Authorization of RA-19-0352 Regarding Use of Alternative for RPV Head Closure Stud Examinations ML22256A2532022-11-14014 November 2022 Issuance of Amendments Regarding the Adoption of Technical Specifications Task Force Traveler TSTF-541, Rev. 2 IR 05000269/20220032022-11-0707 November 2022 Integrated Inspection Station 05000269/2022003 and 05000270/2022003 and 05000287/2022003 ML22301A0112022-11-0303 November 2022 Request for Withholding Information from Public Disclosure Regarding the SLR Application - September 2, 2022 ML22298A0752022-10-27027 October 2022 Request for Withholding Information from Public Disclosure Regarding the Subsequent License Renewal Application Duke Energy Letter Dated July 25, 2022 ML22264A0322022-10-20020 October 2022 _Request for Withholding Information from Public Disclosure Regarding the Subsequent License Renewal Application - Duke Energy Letter Dated July 8, 2022 IR 05000269/20220112022-09-26026 September 2022 NRC Inspection Report 05000269/2022011 and 05000270/2022011 and 05000287/2022011 ML22258A0302022-09-15015 September 2022 Evacuation Time Estimate Reports ML22222A0072022-09-14014 September 2022 Request for Withholding Information from Public Disclosure Regarding the Subsequent License Renewal Application ML22231B1362022-09-0101 September 2022 Review of the Draft Environmental Assessment and Findings of No Significant Impact for Catawba Nuclear Station, H.B. Robinson Steam Electric Plant, and Oconee Nuclear Station Independent Spent Fuel Storage Installation Decommissioning Fundi ML22234A0062022-08-30030 August 2022 SLRA - Closed Public Meeting Summary - August 18, 2022 2024-02-01
[Table view] Category:Meeting Summary
MONTHYEARML23118A2852023-05-0202 May 2023 Public Meeting Summary - 2022 Annual Assessment Meeting Regarding Catawba Nuclear Station, McGuire Nuclear and Oconee Nuclear Station ML22200A0772022-08-0808 August 2022 SLRA - Summary of July 14, 2022 and July 28, 2022 Public Meetings ML22193A0182022-07-18018 July 2022 SLRA - Summary of June 30, 2022 Public Meeting ML22129A0062022-05-10010 May 2022 Summary of April 20, 2022, Meeting with Duke Energy Progress, LLC, to Discuss Proposed License Amendment Request to Revise Reactor Coolant System Pressure Isolation Valve Operational Leakage Surveillance Requirement Frequency (L-2022-LRM 00 ML22124A2052022-05-0404 May 2022 Summary of May 4, 2022, Clarification Call with Duke Energy Carolinas, LLC, Application to Revise TS 3.7.7, Low Pressure Service Water (LPSW) System ML22130A0122022-05-0404 May 2022 SLRA - Summary of April 28, 2022 Public Meeting ML22075A2042022-04-0505 April 2022 SLRA - Summary of March 7, 2022 Public Meeting ML22084A6142022-04-0404 April 2022 SLRA - Summary of March 16, 2022 (Closed Public Meeting) ML22094A1112022-04-0404 April 2022 Public Meeting Summary 2021 Annual Assessment Meeting Catawba Dockets Nos. 50-413 and 50-414; McGuire No. 50-369 and 50-370; Oconee. 50-269, 50-270, and 50-287 ML22063A1162022-03-0808 March 2022 SLRA - Summary of Public Meeting Dated February 17, 2022 ML21341A5542021-12-29029 December 2021 Summary of November 29, 2021, Meeting with Duke Energy Progress, LLC and Duke Energy Carolinas, LLC to Discuss a Planned License Amendment Request to Relocate ML21348A5452021-12-14014 December 2021 December 13, 2021, Clarification Call Summary Use of an Alternative to the ASME Code Case N-853 Acceptance Criteria ML21279A1542021-11-0808 November 2021 August 25, 2021, Oconee Nuclear Station, Units 1, 2, and 3 Subsequent License Renewal Application Public Environmental Scoping Meeting Summary Memo ML21279A1192021-08-25025 August 2021 August 25, 2021, Oconee Nuclear Station, Units 1, 2, and 3 Subsequent License Renewal Application Public Environmental Scoping Meeting Summary ML21195A2712021-07-14014 July 2021 Meeting Summary: Pre-Submittal Meeting for the Oconee Subsequent License Renewal Application (EPID Number: L-2020-RNW-0028) (Docket Numbers: 50 269, 50-270, and 50-287) - Summary ML21195A2692021-07-14014 July 2021 Meeting Summary: Pre-Submittal Meeting for the Oconee Subsequent License Renewal Application (EPID Number: L-2020-RNW-0028) (Docket Numbers: 50 269, 50-270, and 50-287) - Memo ML21102A0612021-04-27027 April 2021 April 14, 2021, Meeting Summary Regarding Pre-Application Meeting to Discuss Proposed Relief Request Related to Code Case N-853 ML21099A0932021-04-0909 April 2021 Public Meeting Summary - 2020 Annual Assessment Meeting Regarding Catawba, McGuire, and Oconee Nuclear Stations ML20266G2192020-11-0303 November 2020 Regulatory Audit Report Regarding License Amendment Request to Revise the Licensing Basis for High Energy Line Breaks Outside of the Containment Building ML20141L4172020-05-20020 May 2020 EOC Public Meeting Summary ML19331A5202019-12-12012 December 2019 Summary of Meeting with Duke Energy Carolinas, LLC to Discuss Submitted License Amendment Request for Oconee Nuclear Station, Units 1, 2, and 3 Regarding High Energy Line Break Licensing Basis ML19220A6702019-08-26026 August 2019 Summary of August 7, 2019, Meeting with Duke Energy Progress, LLC and Duke Energy Carolinas, LLC to Discuss a Proposed License Amendment Request for a Common Emergency Plan ML19207A0172019-07-30030 July 2019 Summary of Meeting with Duke Energy Carolinas, LLC to Discuss Proposed License Amendment Request for Oconee Nuclear Station, Units 1, 2, and 3 Regarding High Energy Line Break Licensing Basis ML19102A3352019-04-12012 April 2019 Public Meeting Summary - Oconee Nuclear Station Docket Nos. 50-269, 50-270, and 50-287 ML19087A0622019-04-11011 April 2019 Summary of March 25, 2019, Public Teleconference with Duke Energy to Discuss the Request for Additional Information Response Regarding the Proposed Alternative to the Depth Sizing Qualification Requirement (Duke Energy Fleet Relief Request ML18227B2122018-09-0505 September 2018 Summary of August 1, 2018, Meeting with Duke Energy Carolinas, LLC to Discuss Proposed License Amendment Request for Oconee Nuclear Station, Units 1, 2, and 3 Regarding Tornado Mitigation Licensing Basis ML18134A2292018-05-14014 May 2018 Summary of April 26, 2018, Public Teleconference with Duke Energy Carolinas, LLC to Discuss Proposed License Amendment and 3 Regarding Technical Specification 3.8.1 ML18082A1082018-03-29029 March 2018 Summary of February 28, 2018, Meeting with Duke Energy Carolinas, LLC to Discuss Proposed LAR Regarding Tornado Mitigation Licensing Basis ML18082A0582018-03-23023 March 2018 Summary of Meeting with Oconee Nuclear Station to Discuss Annual Assessment of Oconee for the Period of January 01, 2017 - December 31, 2017 ML17179A3472017-07-18018 July 2017 Summary of Meeting with Duke Energy Carolinas, LLC to Discuss Proposed License Amendment Request for Oconee Nuclear Station, Units 1, 2, and 3 Regarding Thermal Margin for the Standby Shutdown Facility ML17103A0292017-04-13013 April 2017 Summary of Meeting to Provide Opportunities to Discuss Annual Assessment of Oconee Nuclear Station Units 1, 2 and 3 ML16166A4022016-06-27027 June 2016 Summary of November 18, 2015, and December 15, 2015, Meetings with Duke Energy Carolinas, LLC to Discuss a Proposed Relief Request in Accordance with 10 CFR 50.55a(z) for the Oconee Nuclear Station, Units 1, 2, and 3 ML16132A4352016-05-20020 May 2016 Summary of October 13, 2015, Meeting with Duke Energy Carolinas, LLC to Discuss Proposed LAR to Support Keowee Dam Stator Replacement ML15161A4312015-06-19019 June 2015 Summary of Meeting with Duke Energy Carolinas, LLC, to Discuss Ongoing Major Projects at Oconee Nuclear Station, Units 1, 2 and 3 ML15089A1642015-04-27027 April 2015 Summary of February 25, 2015, Partially Closed Meeting with Industry Stakeholders Regarding the Babcock and Wilcox Loss of Coolant Accident Evaluation Model Analysis ML15113A6262015-04-23023 April 2015 April 14, 2015 Summary of Public Meeting on Oconee Nuclear Station, Units 1, 2 and 3 to Discuss the Annual Assessment ML14356A0052014-12-31031 December 2014 Summary of December 3, 2014, Category 1 Public Meeting with Duke Energy Carolinas, LLC to Discuss NTTF Recommendation 2.1, Flooding Response for Oconee Nuclear Station, Units 1, 2, and 3 ML14147A3652014-05-27027 May 2014 Annual Assessment Public Meeting Summary Memo ML14069A3492014-03-13013 March 2014 Summary of Meeting with Duke Energy Carolinas, LLC, to Discuss Ongoing Major Projects at Oconee Nuclear Station, Units 1, 2, and 3 ML13336A5982013-12-0404 December 2013 Summary of Meeting with Duke Energy Carolinas, LLC, to Discuss the Proposed One-time TS Completion Time Change to Perform Khu Generator Field Pole Rewind Maintenance - Oconee Nuclear Station Units 1, 2, and 3 (TAC Nos. ME9021, ME9022, and M ML13312A9882013-11-0808 November 2013 Summary of Public Meeting with Duke Energy Carolinas, LLC, to Provide Opportunities to Discuss the Planned Fukushima-Related Modifications ML13281A5412013-10-21021 October 2013 9/24/2013 - Oconee Nuclear Station, Units 1, 2, and 3, Summary of Meeting with Duke Energy Carolinas, LLC, to Discuss the Jocassee Dam Seismic Analysis ML13281A6972013-10-21021 October 2013 10/3/13 Summary of Meeting with Duke Energy Carolinas, LLC to Discuss the Protected Service Water System Operation - Oconee Nuclear Station Units 1, 2, and 3 (TAC Nos. ME7737, ME7738, ME7739, ME7746, ME7747, and ME7748) ML13241A4482013-08-29029 August 2013 August 28, 2013 Summary of Public Meeting - Major Projects Status Meeting with Oconee ML13225A2932013-08-12012 August 2013 7/23-24/2013, Summary of Meeting 2013 U.S. Nuclear Regulatory Commission (NRC) Initial Exam Writers' Workshop ML13134A5232013-05-14014 May 2013 5/9/2013 Summary of Public Meeting with Duke Energy Corp., Oconee Nuclear Station to Provide Opportunities to Discuss the Annual Assessment for the Year 2012 ML13122A1912013-05-0606 May 2013 Summary of 04/10/13, Meeting with Duke Energy Carolinas, LLC, to Discuss Milestones Related to an Apparent Violation of License Conditions on Fire Protection (EA-13-010) ML13122A4362013-05-0606 May 2013 Summary of April 9, 2013, Meeting with Duke Energy Carolinas, LLC, to Discuss the Re-evaluation of External Flooding for Oconee Nuclear Station, Units 1, 2, and 3 ML13092A3632013-04-0404 April 2013 3/25/2013 - Oconee Nuclear Station, Units 1, 2, and 3 - Summary of Meeting with Duke Energy Carolinas, LLC, to Discuss the Flood Hazard Reevaluation Report ML13072A4262013-03-18018 March 2013 3/5/13 Summary of Meeting with Oconee Nuclear Station, Units 1, 2, and 3 - Predecisional Enforcement Conference Summary 2023-05-02
[Table view] |
Text
October 29, 2002 Mr. William R. McCollum, Jr.
Vice President, Oconee Site Duke Energy Corporation 7800 Rochester Highway Seneca, SC 29672
SUBJECT:
SUMMARY
OF CONFERENCE CALL WITH DUKE ENERGY COMPANY REGARDING THE 2002 STEAM GENERATOR INSPECTION RESULTS AT OCONEE NUCLEAR STATION, UNIT 1 (TAC NO. MB4458)
Dear Mr. McCollum:
On March 14, 19, and 25, and April 5, 17, and 22, 2002, your staff and our staff participated in conference calls regarding the steam generator inspection activities at Oconee Nuclear Station, Unit 1. Enclosure 1 is a brief summary of the calls, and Enclosures 2 and 3 contain material your staff sent us in preparation for the calls.
Based on the information discussed during the calls, we did not identify any issues requiring further discussion.
Sincerely,
/RA/
Leonard N. Olshan, Project Manager, Section 1 Project Directorate II Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-269
Enclosures:
- 1. Summary of Calls with Duke Energy Company Regarding 2002 Steam Generator Results at Oconee Nuclear Station, Unit 1
- 2. ONS 1EOC-20 Steam Generator Inspection Plans
- 3. ONS-1B Sever of Tube 78-124 cc w/encls: See next page
October 29, 2002 Mr. William R. McCollum, Jr.
Vice President, Oconee Site Duke Energy Corporation 7800 Rochester Highway Seneca, SC 29672
SUBJECT:
SUMMARY
OF CONFERENCE CALL WITH DUKE ENERGY COMPANY REGARDING THE 2002 STEAM GENERATOR INSPECTION RESULTS AT OCONEE NUCLEAR STATION, UNIT 1 (TAC NO. MB4458)
Dear Mr. McCollum:
On March 14, 19, and 25, and April 5, 17, and 22, 2002, your staff and our staff participated in conference calls regarding the steam generator inspection activities at Oconee Nuclear Station, Unit 1. Enclosure 1 is a brief summary of the calls, and Enclosures 2 and 3 contain material your staff sent us in preparation for the calls.
Based on the information discussed during the calls, we did not identify any issues requiring further discussion.
Sincerely,
/RA/
Leonard N. Olshan, Project Manager, Section 1 Project Directorate II Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-269
Enclosures:
- 1. Summary of Calls with Duke Energy Company Regarding 2002 Steam Generator Results at Oconee Nuclear Station, Unit 1
- 2. ONS 1EOC-20 Steam Generator Inspection Plans
- 3. ONS-1B Sever of Tube 78-124 cc w/encls: See next page Distribution:
PUBLIC HBerkow MLesser PDII-1 R/F JNakoski SRosenberg LOlshan CHawes RHaag, RII OGC MKotzalas ACRS/ACNW BFu JZwolinski/LMarsh KKarwoski ADAMS ACCESSION No: ML023020010 OFFICE PDII-1/PM PDII-1/LA PDII-1/SC NAME LOlshan CHawes JNakoski DATE 10/25/02 10/24/02 10/25/02 OFFICIAL RECORD COPY
SUMMARY
OF CONFERENCE CALLS WITH DUKE ENERGY COMPANY REGARDING 2002 STEAM GENERATOR INSPECTION RESULTS AT OCONEE NUCLEAR STATION, UNIT 1 The NRC staff participated in conference calls with Duke Energy Company (the licensee) on March 14, 19, and 25, and April 5, 17, and 22, 2002, to discuss the steam generator (SG) inspection results from the 20th refueling outage at Oconee Nuclear Station, Unit 1 (Oconee 1).
During the calls prior to and on April 17, 2002, the NRC staff and the licensee discussed the licensees actions in response to NRC Information Notice 2002-02 (IN 2002-02), Recent Experience with Plugged Steam Generator Tubes (ADAMS Accession Number ML013480327). As discussed in the information notice, certain plugged tubes may be susceptible to severance as a result of tube vibration and other factors (e.g., tube swelling).
The scope of the licensees inspection is included in the materials provided by the licensee in support of these calls.
On April 22, 2002, the NRC and the licensee discussed the steam generator tube inspection scope, the eddy current data analysis results, tube plugging and repair plans, and in-situ pressure testing. At the time of the call, the licensee had already completed the inspection.
Details of the inspection results are contained in the attached inspection summary that the licensee provided in support of this call. Additional clarifying information provided during the call is provided below.
The inspection scope included the following:
C 100% of tubes in both SGs by bobbin probes C 100% of sleeved tubes in both SGs by bobbin probes C Lane and wedge areas with two rows around the sleeved tubes with plus point probes C 100% of the upper tube sheet with plus point probes C 100% of re-rolls in the upper tube sheet with plus point probes C 100% of I-600 plugs with plus point probes C 100% of the sleeve upper and lower rolls C 100% of tubes in the kidney region (sludge piles) with plus point probes C Rotating pancake coil (RPC) for areas of special interest, including 100% of bobbin indications and 100% of all dents regardless of size or location Prior to shutdown for the inspection, Oconee 1 was experiencing a 1 to 2 gallons per day primary-to-secondary leak. However, no secondary side pressure tests were conducted during the outage.
During the April 22, 2002, phone call, the licensee discussed the location and size of significant indications detected during the outage inspection that will be included in the 90-day report Enclosure 1
issued after the outage. The licensee discussed two indications detected at dents, one was axial in nature and the other was circumferential. Both indications initiated from the inside diameter of the tube. The licensee stated that the axial indication was considered small. The licensee also discussed indications found in the freespan region. The freespan cracks were axial in nature and initiated from the outside diameter.
Six tubes were in-situ pressure tested during the 20th refueling outage. These tubes contained axial freespan primary water stress corrosion cracking indications located at dents, axial outside diameter stress corrosion cracking/intergranular attack indications, and volumetric indications.
The licensees in-situ pressure-testing criteria used crack length and indication voltage to determine whether an indication fell within a required zone for testing. According to the licensees screening criteria, only some of these indications required testing up to the structural integrity limit of three times the normal operating differential pressure (3P). During these tests, all tubes maintained leakage integrity, and all tubes chosen for testing up to the 3P limit maintained structural integrity. The graphical representation of the in-situ pressure-testing criteria suggests that a flaw with a relatively large crack length but low voltage would not fall in the required zone of testing. The licensee indicated that it historically has in-situ pressure tested selected tubes even though the selection criteria indicated the licensee did not need to test them.
As a result of inspecting plugged tubes in response to the information contained in Information Notice 2002-02, the licensee identified a wear scar on a plugged tube (B77-123). Because this indication was not present when the tube was plugged in 1991, the licensee performed a secondary side visual inspection. This inspection led to the discovery of a circumferentially severed plugged tube (B78-124) next to the affected (B77-123) tube. Tube B78-124 was severed at the secondary face of the lower tube sheet. The licensee performed in-situ pressure tests on the tubes with wear scars and reported that the test results were satisfactory, indicating that the severed tube had not significantly impacted the integrity of its neighboring tubes (all of which were plugged during prior outages).
The licensee removed portions of several of the affected tubes for destructive examination, including the severed tube. The destructive examinations, although inconclusive, indicated that the tube severed as a result of intergranular attack originating from the inside diameter of the tube. There were no obvious indications of fatigue or significant ductile tearing. The severed tube was 1 of 12 tubes instrumented with thermocouples during the first cycle of operation (early 1970s). The tubes in which these thermocouples were installed were plugged at one end while the other end remained open. Following the first cycle of operation, the thermocouples were removed and the tubes were plugged at the open end. The licensee speculated that the instrumentation (thermocouple) installed for the first cycle of operation is one of the causal factors. After the completion of the licensees root cause evaluation, the NRC staff issued an information notice that summarized the finding (Refer to IN 2002-02, Supp. 1.).
At the conclusion of the April 22, 2002, call, the NRC staff requested that the licensee contact the NRC if the licensee identifies anything significantly different from that discussed during the call. The NRC staff also expressed an interest in receiving an update on the licensees metallurgical analysis of the severed plugged tube and on the final root cause determination.
Oconee Nuclear Station cc:
Ms. Lisa F. Vaughn Mr. L. E. Nicholson Legal Department (PBO5E) Compliance Manager Duke Energy Corporation Duke Energy Corporation 422 South Church Street Oconee Nuclear Site Charlotte, North Carolina 28201-1006 7800 Rochester Highway Seneca, South Carolina 29672 Anne W. Cottingham, Esquire Winston and Strawn Ms. Karen E. Long 1400 L Street, NW Assistant Attorney General Washington, DC 20005 North Carolina Department of Justice Manager, LIS P. O. Box 629 NUS Corporation Raleigh, North Carolina 27602 2650 McCormick Drive, 3rd Floor Clearwater, Florida 34619-1035 Mr. C. Jeffrey Thomas Manager - Nuclear Regulatory Senior Resident Inspector Licensing U. S. Nuclear Regulatory Duke Energy Corporation Commission 526 South Church Street 7812B Rochester Highway Charlotte, North Carolina 28201-1006 Seneca, South Carolina 29672 Mr. Richard M. Fry, Director Mr. Henry Porter, Director Division of Radiation Protection Division of Radioactive Waste Management North Carolina Department of Bureau of Land and Waste Management Environment, Health, and Department of Health and Environmental Natural Resources Control 3825 Barrett Drive 2600 Bull Street Raleigh, North Carolina 27609-7721 Columbia, South Carolina 29201-1708 Mr. Peter R. Harden, IV Mr. Michael A. Schoppman VP-Customer Relations and Sales Framatome ANP Westinghouse Electric Company 1911 North Ft. Myer Drive 6000 Fairview Road Suite 705 12th Floor Rosslyn, VA 22209 Charlotte, North Carolina 28210