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| {{#Wiki_filter:0 FPL.POWERING TODAY.EMPOWERING TOMORROW.0 May 14, 2010 L-2010-100 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 Srecial Report -Accident Monitorinci Instrumentation In accordance with Technical Specifications 6.9.2 and 3.3.3.3, the attached Special Report is provided for your information. | | {{#Wiki_filter:0 FPL.POWERING TODAY.EMPOWERING TOMORROW.0 May 14, 2010 L-2010-100 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 Srecial Report -Accident Monitorinci Instrumentation In accordance with Technical Specifications 6.9.2 and 3.3.3.3, the attached Special Report is provided for your information. |
| Should there be any questions regarding this information, please contact Robert J. Tomonto, Licensing Manager at (305) 246-7327.Sincerely, Michael Kiley Vice President Turkey Point Nuclear Plant SM cc: Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant an FPL Group company L-2010-100 Page 2 of 3 SPECIAL REPORT Purpose: This special report is being submitted pursuant to the requirements of Turkey Point Unit 4 Technical Specification (TS) 3.3.3.3, Table 3.3-5, Instrument 19.d Accident Monitoring Instrumentation, Action 34, part 2 due to the Main Steam Lines High Range-Noble Gas Effluent Monitor, (DAM-i, RAD 6426), being inoperable for greater than 7 days.Required Action 34 of TS 3.3.3.3, Table 3.3-5, for Item 19.d, states: "With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirements, initiate the preplanned alternate method of monitoring the appropriate parameter(s), within 72 hours, and: 1) Either restore the inoperable channel(s) to OPERABLE status within 7 days of the event, or 2) Prepare and submit a Special Report to the Commission pursuant to Specification 6.9.2 within the next 14 days outlining the action taken, the cause of the inoperability, and the plans and schedule for restoring the system to OPERABLE status." Event and Action Taken: The Process Radiation Monitor (RAD-6426), with Data Acquisition Monitor (DAM-1), is a common Turkey Point Units 3 and 4 Main Steam Lines radiation monitor. The detector reacts to the activity in the main steam line by sampling the main steam at a point in the main steam lines immediately outside of containment and upstream of release paths such as atmospheric dump lines and safety valves. Detected high radiation would be indicative of a primary to secondary leak. The normal background count rate is approximately one count per minute under normal, non-accident conditions. | | Should there be any questions regarding this information, please contact Robert J. Tomonto, Licensing Manager at (305) 246-7327.Sincerely, Michael Kiley Vice President Turkey Point Nuclear Plant SM cc: Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant an FPL Group company L-2010-100 Page 2 of 3 SPECIAL REPORT Purpose: This special report is being submitted pursuant to the requirements of Turkey Point Unit 4 Technical Specification (TS) 3.3.3.3, Table 3.3-5, Instrument 19.d Accident Monitoring Instrumentation, Action 34, part 2 due to the Main Steam Lines High Range-Noble Gas Effluent Monitor, (DAM-i, RAD 6426), being inoperable for greater than 7 days.Required Action 34 of TS 3.3.3.3, Table 3.3-5, for Item 19.d, states: "With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirements, initiate the preplanned alternate method of monitoring the appropriate parameter(s), within 72 hours, and: 1) Either restore the inoperable channel(s) to OPERABLE status within 7 days of the event, or 2) Prepare and submit a Special Report to the Commission pursuant to Specification |
| | |
| | ====6.9.2 within==== |
| | the next 14 days outlining the action taken, the cause of the inoperability, and the plans and schedule for restoring the system to OPERABLE status." Event and Action Taken: The Process Radiation Monitor (RAD-6426), with Data Acquisition Monitor (DAM-1), is a common Turkey Point Units 3 and 4 Main Steam Lines radiation monitor. The detector reacts to the activity in the main steam line by sampling the main steam at a point in the main steam lines immediately outside of containment and upstream of release paths such as atmospheric dump lines and safety valves. Detected high radiation would be indicative of a primary to secondary leak. The normal background count rate is approximately one count per minute under normal, non-accident conditions. |
| If there is no count in any 10 minute period, the DAM-1 microprocessor registers a "LO count" failure.On April 25, 2010, both Turkey Point Units 3 and 4 were operating in Mode 1, when the DAM-1 microprocessor alarmed locally and registered a "LO count" failure. On April 25, 2010, at 1715, Operations declared the Main Steam Lines High Range-Noble Gas Effluent Monitor (DAM-1) out of service, in accordance with TS 3.3.3.3, Table 3.3-5, and Instrument 19.d, which requires this monitor to be OPERABLE in Modes 1-3.A work request was generated to troubleshoot and repair DAM-I. The alternate monitoring was initiated within 72 hours as required by TS 3.3.3.3, Table 3.3-5, Action 34 and it was in place for the entire time the monitor was inoperable. | | If there is no count in any 10 minute period, the DAM-1 microprocessor registers a "LO count" failure.On April 25, 2010, both Turkey Point Units 3 and 4 were operating in Mode 1, when the DAM-1 microprocessor alarmed locally and registered a "LO count" failure. On April 25, 2010, at 1715, Operations declared the Main Steam Lines High Range-Noble Gas Effluent Monitor (DAM-1) out of service, in accordance with TS 3.3.3.3, Table 3.3-5, and Instrument 19.d, which requires this monitor to be OPERABLE in Modes 1-3.A work request was generated to troubleshoot and repair DAM-I. The alternate monitoring was initiated within 72 hours as required by TS 3.3.3.3, Table 3.3-5, Action 34 and it was in place for the entire time the monitor was inoperable. |
| DAM-1 was not restored within 7 days of the event, (prior to May 2, 2010) due to continuing troubleshooting and repair activities. | | DAM-1 was not restored within 7 days of the event, (prior to May 2, 2010) due to continuing troubleshooting and repair activities. |
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Category:Letter type:L
MONTHYEARL-2024-158, Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-09-25025 September 2024 Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes L-2024-136, Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-09-16016 September 2024 Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes L-2024-122, Core Operating Limits Report2024-08-12012 August 2024 Core Operating Limits Report L-2024-106, Fifth and Sixth 10-Year Inservice Testing Interval Relief Request No. VR-022024-08-12012 August 2024 Fifth and Sixth 10-Year Inservice Testing Interval Relief Request No. VR-02 L-2024-089, Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP- 17 451-P. Revision 1. Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections2024-07-25025 July 2024 Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP- 17 451-P. Revision 1. Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections L-2024-125, Notice of Intent to Provide Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-07-24024 July 2024 Notice of Intent to Provide Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes L-2024-112, Condition Prohibited by Technical Specifications2024-07-10010 July 2024 Condition Prohibited by Technical Specifications L-2024-114, Quality Assurance Topical Report (FPL-1 Revision 31 Annual Submittal2024-07-10010 July 2024 Quality Assurance Topical Report (FPL-1 Revision 31 Annual Submittal L-2024-102, Official Service List Update2024-06-19019 June 2024 Official Service List Update L-2024-100, Withdrawal of License Amendment Request 274, Reactor Protection System, Engineered Safety Features Actuation System, and Nuclear Instrumentation System Replacement Project2024-06-19019 June 2024 Withdrawal of License Amendment Request 274, Reactor Protection System, Engineered Safety Features Actuation System, and Nuclear Instrumentation System Replacement Project L-2024-076, Reply to Notice of Violation; NOV 05000250, 05000251/2024010-052024-05-29029 May 2024 Reply to Notice of Violation; NOV 05000250, 05000251/2024010-05 L-2024-082, 2023 Annual Radiological Environmental Operating Report2024-05-15015 May 2024 2023 Annual Radiological Environmental Operating Report L-2024-060, 10 CFR 50.59(d)(2) Evaluation and 10 CFR 50.71(e)(2) Technical Specification Bases Summaries Report2024-05-0909 May 2024 10 CFR 50.59(d)(2) Evaluation and 10 CFR 50.71(e)(2) Technical Specification Bases Summaries Report L-2024-073, Cycle 34 Core Operating Limits Report2024-05-0101 May 2024 Cycle 34 Core Operating Limits Report L-2024-072, Cycle 33 Core Operating Limits Report2024-05-0101 May 2024 Cycle 33 Core Operating Limits Report L-2024-048, Divider Plate Assemblies Bounding Analysis Evaluation for Subsequent License Renewal Commitment Revision2024-04-30030 April 2024 Divider Plate Assemblies Bounding Analysis Evaluation for Subsequent License Renewal Commitment Revision L-2024-069, Radiological Emergency Plan Revision 762024-04-22022 April 2024 Radiological Emergency Plan Revision 76 L-2024-066, Sixth 10-Year Inservice Testing Interval Relief Request No. PR-022024-04-17017 April 2024 Sixth 10-Year Inservice Testing Interval Relief Request No. PR-02 L-2024-057, 0 for Turkey Point, Unit 3 - Condition Prohibited by Technical Specifications2024-04-11011 April 2024 0 for Turkey Point, Unit 3 - Condition Prohibited by Technical Specifications L-2024-040, Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP-17451-P, Revision 1, Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections2024-03-28028 March 2024 Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP-17451-P, Revision 1, Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections L-2024-047, Proposed Use of a Subsequent ASME Code Edition and Addenda2024-03-28028 March 2024 Proposed Use of a Subsequent ASME Code Edition and Addenda L-2024-013, Submittal of Periodic Reports2024-03-28028 March 2024 Submittal of Periodic Reports L-2024-044, Revised Steam Generator Tube Inspection Reports2024-03-19019 March 2024 Revised Steam Generator Tube Inspection Reports L-2024-011, and Point Beach, Units 1 and 2 - 10 CFR 50.46 Annual Reporting of Changes to, or Errors in Emergency Core Cooling System Models or Applications2024-03-13013 March 2024 and Point Beach, Units 1 and 2 - 10 CFR 50.46 Annual Reporting of Changes to, or Errors in Emergency Core Cooling System Models or Applications L-2024-014, 2023 Annual Radioactive Effluent Release Report2024-02-29029 February 2024 2023 Annual Radioactive Effluent Release Report L-2024-025, Notification of Improved Standard Technical Specifications (ITS) Implementation2024-02-22022 February 2024 Notification of Improved Standard Technical Specifications (ITS) Implementation L-2024-008, Supplement to License Amendment Request 278. Incorporate Advanced Fuel Products. Extend Surveillance Intervals and 10 CFR 50.46 Exemption Request to Facilitate Transition to 24-Month Fuel Cycles2024-02-0909 February 2024 Supplement to License Amendment Request 278. Incorporate Advanced Fuel Products. Extend Surveillance Intervals and 10 CFR 50.46 Exemption Request to Facilitate Transition to 24-Month Fuel Cycles L-2024-010, Point Units 3 and 4, Seabrook, Duane Arnold, and Point Beach Units 1 and 2, Nuclear Property Insurance - 10 CFR 50.54(w)(3)2024-01-25025 January 2024 Point Units 3 and 4, Seabrook, Duane Arnold, and Point Beach Units 1 and 2, Nuclear Property Insurance - 10 CFR 50.54(w)(3) L-2024-007, Inservice Inspection Program Owners Activity Report (OAR-1)2024-01-18018 January 2024 Inservice Inspection Program Owners Activity Report (OAR-1) L-2023-173, Quality Assurance Topical Report (FPL-1) Revision 30 Update2023-12-15015 December 2023 Quality Assurance Topical Report (FPL-1) Revision 30 Update L-2023-172, Supplement to Exemption Request Regarding Enhanced Weapons. Firearms Background Checks. and Security Event Notifications Final Rule2023-11-29029 November 2023 Supplement to Exemption Request Regarding Enhanced Weapons. Firearms Background Checks. and Security Event Notifications Final Rule L-2023-155, Supplement to Response to Request for Additional Information, Revised NextEra Common Emergency Plan, and Revised Site-Specific Emergency Plan Annexes Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-06542023-11-28028 November 2023 Supplement to Response to Request for Additional Information, Revised NextEra Common Emergency Plan, and Revised Site-Specific Emergency Plan Annexes Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-0654, L-2023-146, Part 73 Exemption Request Regarding Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Final Rule2023-11-16016 November 2023 Part 73 Exemption Request Regarding Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Final Rule L-2023-078, License Amendment Request 278, Incorporate Advanced Fuel Products, Extend Surveillance Intervals and 10 CFR 50.46 Exemption Request to Facilitate Transition to 24-Month Fuel Cycles2023-11-15015 November 2023 License Amendment Request 278, Incorporate Advanced Fuel Products, Extend Surveillance Intervals and 10 CFR 50.46 Exemption Request to Facilitate Transition to 24-Month Fuel Cycles L-2023-077, License Amendment Request 277 Updated Spent Fuel Pool Criticality Analysis2023-10-11011 October 2023 License Amendment Request 277 Updated Spent Fuel Pool Criticality Analysis L-2023-110, Response to Requests for Additional Information Regarding License Amendment Request No. 276, Revise Fire Protection Program in Support of Reactor Coolant Pump Seal Replacement Project2023-08-25025 August 2023 Response to Requests for Additional Information Regarding License Amendment Request No. 276, Revise Fire Protection Program in Support of Reactor Coolant Pump Seal Replacement Project L-2023-115, Inservice Inspection Program Owner'S Activity Report (OAR-1)2023-08-21021 August 2023 Inservice Inspection Program Owner'S Activity Report (OAR-1) L-2023-114, Proposed Turkey Point Units 6 and 7; Seabrook Station; Point Beach Units 1 and 2 - Official Service List Update2023-08-17017 August 2023 Proposed Turkey Point Units 6 and 7; Seabrook Station; Point Beach Units 1 and 2 - Official Service List Update L-2023-098, and Point Beach Units 1 and 2 - Response to Request for Additional Information Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-0654, Revision 22023-08-0707 August 2023 and Point Beach Units 1 and 2 - Response to Request for Additional Information Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-0654, Revision 2 L-2023-094, Response to Requests for Additional Information Regarding License Amendment Request No. 276, Revise Fire Protection Program in Support of Reactor Coolant Pump Seal Replacement Project2023-07-27027 July 2023 Response to Requests for Additional Information Regarding License Amendment Request No. 276, Revise Fire Protection Program in Support of Reactor Coolant Pump Seal Replacement Project L-2023-087, Florida Power & Light/Nextera Energy, Results of the Safety Culture Program Effectiveness Review, March 20, 2023 (ADAMS Accession No. ML22340A452)2023-06-29029 June 2023 Florida Power & Light/Nextera Energy, Results of the Safety Culture Program Effectiveness Review, March 20, 2023 (ADAMS Accession No. ML22340A452) L-2023-086, Request Temporary Suspension of Turkey Point License Amendment Request 274, Reactor Protection System, Engineered Safety Features Actuation System, and Nuclear Instrumentation.2023-06-28028 June 2023 Request Temporary Suspension of Turkey Point License Amendment Request 274, Reactor Protection System, Engineered Safety Features Actuation System, and Nuclear Instrumentation. L-2023-074, Addendum to 2021 Decommissioning Funding Status Reports / Independent Spent Fuel Storage Installation Ctsfsi) Financial Assurance Update2023-06-0202 June 2023 Addendum to 2021 Decommissioning Funding Status Reports / Independent Spent Fuel Storage Installation Ctsfsi) Financial Assurance Update L-2023-069, Response to Requests for Additional Information Regarding License Amendment Request No. 276, Revise Fire Protection Program in Support of Reactor Coolant Pump Seal Replacement Project2023-05-31031 May 2023 Response to Requests for Additional Information Regarding License Amendment Request No. 276, Revise Fire Protection Program in Support of Reactor Coolant Pump Seal Replacement Project L-2023-072, Preparation and Scheduling of Operator Licensing Examinations2023-05-22022 May 2023 Preparation and Scheduling of Operator Licensing Examinations L-2023-071, NextEra Energy Quality Assurance Topical Report (FPL-1) Revision 29 and Florida Power and Light Company Quality Assurance Program Description for 10 CFR Part 52 Licenses (FPL-2) Revision 11, Annual Submittal2023-05-22022 May 2023 NextEra Energy Quality Assurance Topical Report (FPL-1) Revision 29 and Florida Power and Light Company Quality Assurance Program Description for 10 CFR Part 52 Licenses (FPL-2) Revision 11, Annual Submittal L-2023-061, 2022 Annual Radiological Environmental Operating Report2023-05-12012 May 2023 2022 Annual Radiological Environmental Operating Report L-2023-062, Cycle 33 Core Operating Limits Report2023-04-27027 April 2023 Cycle 33 Core Operating Limits Report L-2023-060, Radiological Emergency Plan, Revision 752023-04-26026 April 2023 Radiological Emergency Plan, Revision 75 L-2023-054, Submittal of Periodic Reports2023-04-12012 April 2023 Submittal of Periodic Reports 2024-09-25
[Table view] Category:Licensee 30-Day Written Event Report
MONTHYEARL-2019-058, CFR 50.46 - Emergency Core Cooling System LBLOCA 30-Day Report2019-03-25025 March 2019 CFR 50.46 - Emergency Core Cooling System LBLOCA 30-Day Report L-2018-063, CFR 50.46 Annual Reporting and 30-day Notification of Changes or Errors in Emergency Core Cooling System Models or Applications2018-03-26026 March 2018 CFR 50.46 Annual Reporting and 30-day Notification of Changes or Errors in Emergency Core Cooling System Models or Applications L-2017-102, Submittal of 10 CFR 50.46 - Emergency Core Cooling 30-Day Report2017-06-0202 June 2017 Submittal of 10 CFR 50.46 - Emergency Core Cooling 30-Day Report L-2017-069, Special Report - Containment Tendon Corrosion Protection Medium Volume Reduction2017-04-17017 April 2017 Special Report - Containment Tendon Corrosion Protection Medium Volume Reduction L-2016-124, 10 CFR 50.46 30-Day Report for Turkey Point, Seabrook, and Point Beach2016-06-17017 June 2016 10 CFR 50.46 30-Day Report for Turkey Point, Seabrook, and Point Beach L-2016-065, Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors, - 30 Day Special Report2016-04-0505 April 2016 Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors, - 30 Day Special Report L-2014-359, 10 CFR 50.46 Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors, 30 Day Special Report2014-12-0303 December 2014 10 CFR 50.46 Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors, 30 Day Special Report L-2014-077, CFR 50.46, Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors - 30 Day Special Report2014-03-24024 March 2014 CFR 50.46, Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors - 30 Day Special Report L-2014-065, Special Report - Accident Monitoring Instrumentation2014-02-25025 February 2014 Special Report - Accident Monitoring Instrumentation L-2014-037, Emergency Core Cooling Systems in Light Water Nuclear Power Reactors - 30 Day Special Report2014-02-18018 February 2014 Emergency Core Cooling Systems in Light Water Nuclear Power Reactors - 30 Day Special Report L-2013-184, Special Report - Accident Monitoring Instrumentation2013-05-30030 May 2013 Special Report - Accident Monitoring Instrumentation L-2013-117, Special Report - Accident Monitoring Instrumentation2013-03-29029 March 2013 Special Report - Accident Monitoring Instrumentation L-2010-235, LER, Turkey Point, Units 3 and 4, Special Report - Accident Monitoring Instrumentation Inoperable2010-10-13013 October 2010 LER, Turkey Point, Units 3 and 4, Special Report - Accident Monitoring Instrumentation Inoperable L-2010-114, Special Report Re Inoperable Main Steam Lines High Range-Noble Gas Effluent Monitor Greater than 7 Days2010-06-14014 June 2010 Special Report Re Inoperable Main Steam Lines High Range-Noble Gas Effluent Monitor Greater than 7 Days L-2010-100, Accident Monitoring Instrumentation Special Report2010-05-14014 May 2010 Accident Monitoring Instrumentation Special Report L-2005-096, CFR 50.46, Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors - Annual Report and 30-Day Report2005-04-27027 April 2005 CFR 50.46, Acceptance Criteria for Emergency Core Cooling Systems in Light Water Nuclear Power Reactors - Annual Report and 30-Day Report ML18227A5071977-07-29029 July 1977 Transmittal of Licensee Event Report 251-77-4, Steam Generator Tube Plugs ML18227A5081977-05-13013 May 1977 Transmittal of Licensee Event Report 251-77-2 Boric Acid Transfer Pumps 2019-03-25
[Table view] |
Text
0 FPL.POWERING TODAY.EMPOWERING TOMORROW.0 May 14, 2010 L-2010-100 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 Srecial Report -Accident Monitorinci Instrumentation In accordance with Technical Specifications 6.9.2 and 3.3.3.3, the attached Special Report is provided for your information.
Should there be any questions regarding this information, please contact Robert J. Tomonto, Licensing Manager at (305) 246-7327.Sincerely, Michael Kiley Vice President Turkey Point Nuclear Plant SM cc: Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant an FPL Group company L-2010-100 Page 2 of 3 SPECIAL REPORT Purpose: This special report is being submitted pursuant to the requirements of Turkey Point Unit 4 Technical Specification (TS) 3.3.3.3, Table 3.3-5, Instrument 19.d Accident Monitoring Instrumentation, Action 34, part 2 due to the Main Steam Lines High Range-Noble Gas Effluent Monitor, (DAM-i, RAD 6426), being inoperable for greater than 7 days.Required Action 34 of TS 3.3.3.3, Table 3.3-5, for Item 19.d, states: "With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirements, initiate the preplanned alternate method of monitoring the appropriate parameter(s), within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, and: 1) Either restore the inoperable channel(s) to OPERABLE status within 7 days of the event, or 2) Prepare and submit a Special Report to the Commission pursuant to Specification
6.9.2 within
the next 14 days outlining the action taken, the cause of the inoperability, and the plans and schedule for restoring the system to OPERABLE status." Event and Action Taken: The Process Radiation Monitor (RAD-6426), with Data Acquisition Monitor (DAM-1), is a common Turkey Point Units 3 and 4 Main Steam Lines radiation monitor. The detector reacts to the activity in the main steam line by sampling the main steam at a point in the main steam lines immediately outside of containment and upstream of release paths such as atmospheric dump lines and safety valves. Detected high radiation would be indicative of a primary to secondary leak. The normal background count rate is approximately one count per minute under normal, non-accident conditions.
If there is no count in any 10 minute period, the DAM-1 microprocessor registers a "LO count" failure.On April 25, 2010, both Turkey Point Units 3 and 4 were operating in Mode 1, when the DAM-1 microprocessor alarmed locally and registered a "LO count" failure. On April 25, 2010, at 1715, Operations declared the Main Steam Lines High Range-Noble Gas Effluent Monitor (DAM-1) out of service, in accordance with TS 3.3.3.3, Table 3.3-5, and Instrument 19.d, which requires this monitor to be OPERABLE in Modes 1-3.A work request was generated to troubleshoot and repair DAM-I. The alternate monitoring was initiated within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> as required by TS 3.3.3.3, Table 3.3-5, Action 34 and it was in place for the entire time the monitor was inoperable.
DAM-1 was not restored within 7 days of the event, (prior to May 2, 2010) due to continuing troubleshooting and repair activities.
As such, the DAM-1 monitor remained inoperable for greater than 7 days.
L-2010-100 Page 3 of 3 Troubleshooting revealed that the DAM-1 Geiger Mueller detector had failed and caused the loss of counts. The inoperability of the detector was prolonged due to multiple intermittent cable related failures.Corrective actions included the replacement of the Geiger-Mueller detector and repair/replacement of failed cables.Cause: The apparent cause evaluation is ongoing. The most probable cause is the Geiger-Mueller detector failure with cable issues as contributing causes.Schedule for Restoration:
The process radiation monitor DAM-1 was returned to service on May 11, 2010 at 1500.