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Category:Letter type:RNP
MONTHYEARRNP-RA/21-0035, Duke Energy Progress, Inc - Independent Spent Fuel Storage Installation Annual Radioactive Effluent Release Report2021-02-18018 February 2021 Duke Energy Progress, Inc - Independent Spent Fuel Storage Installation Annual Radioactive Effluent Release Report RNP-RA/20-0234, Independent Spent Fuel Storage Installation, Registration of Use of Spent Fuel Casks2020-07-23023 July 2020 Independent Spent Fuel Storage Installation, Registration of Use of Spent Fuel Casks RNP-RA/20-0199, Registration of Use of Spent Fuel Casks2020-06-25025 June 2020 Registration of Use of Spent Fuel Casks RNP-RA/18-0063, Request for Extension of Due Date for Seismic Probabilistic Risk Assessment Submittal2018-11-29029 November 2018 Request for Extension of Due Date for Seismic Probabilistic Risk Assessment Submittal RNP-RA/18-0060, Transmittal of Core Operating Limits Report2018-10-17017 October 2018 Transmittal of Core Operating Limits Report RNP-RA/18-0050, Response to Supplemental Request for Additional Information Regarding License Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specification 3.8.1, AC Sources - Operating and the Use of Load Tap Change2018-08-0101 August 2018 Response to Supplemental Request for Additional Information Regarding License Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specification 3.8.1, AC Sources - Operating and the Use of Load Tap Change RNP-RA/18-0044, Supplement to License Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specification 3.8.1, AC Sources - Operating and the Use of Load Tap Changers in the Automatic Mode of Operation on the Startup Transform2018-07-11011 July 2018 Supplement to License Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specification 3.8.1, AC Sources - Operating and the Use of Load Tap Changers in the Automatic Mode of Operation on the Startup Transformers RNP-RA/18-0039, Transmittal of Emergency Procedure Revisions and 10 CFR 50.54(q) Summary of Analysis2018-06-27027 June 2018 Transmittal of Emergency Procedure Revisions and 10 CFR 50.54(q) Summary of Analysis RNP-RA/18-0041, Independent Spent Fuel Storage Installation - Register as User for Cask2018-06-13013 June 2018 Independent Spent Fuel Storage Installation - Register as User for Cask RNP-RA/18-0036, Response to Request for Additional Information (RAI) Regarding Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specification 3.8.1, AC Sources - Operating and the Use ...2018-05-16016 May 2018 Response to Request for Additional Information (RAI) Regarding Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specification 3.8.1, AC Sources - Operating and the Use ... RNP-RA/18-0029, Submittal of 2017 Annual Radiological Environmental Operating Report2018-05-0808 May 2018 Submittal of 2017 Annual Radiological Environmental Operating Report RNP-RA/18-0031, (Hbrsep), Unit 2 - 2017 Annual Radioactive Effluent Release Report and Offsite Dose Calculation Manual, Revision 352018-04-23023 April 2018 (Hbrsep), Unit 2 - 2017 Annual Radioactive Effluent Release Report and Offsite Dose Calculation Manual, Revision 35 RNP-RA/18-0015, Application for Technical Specifications Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequently Requirements to a Licensee Controlled Program2018-04-16016 April 2018 Application for Technical Specifications Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequently Requirements to a Licensee Controlled Program RNP-RA/18-0024, Report of Changes Pursuant to 10 CFR 50.59(d)(2)2018-04-0202 April 2018 Report of Changes Pursuant to 10 CFR 50.59(d)(2) RNP-RA/18-0020, Notification of Change in Licensed Operator Status2018-02-20020 February 2018 Notification of Change in Licensed Operator Status RNP-RA/18-0003, Independent Spent Fuel Storage Installation Annual Radioactive Effluent Release Report2018-01-23023 January 2018 Independent Spent Fuel Storage Installation Annual Radioactive Effluent Release Report RNP-RA/17-0085, Request for Additional Information Regarding Application to Revise Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles2018-01-0808 January 2018 Request for Additional Information Regarding Application to Revise Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles RNP-RA/17-0086, Transmittal of Emergency Procedure Revision and 10 CFR 50.54(q) Summary of Analyses2017-12-14014 December 2017 Transmittal of Emergency Procedure Revision and 10 CFR 50.54(q) Summary of Analyses RNP-RA/17-0081, Submittal of Change in Licensed Operators Medical Status2017-12-11011 December 2017 Submittal of Change in Licensed Operators Medical Status RNP-RA/17-0079, Operator License Renewal Application2017-12-0707 December 2017 Operator License Renewal Application RNP-RA/17-0071, Independent Spent Fuel Storage Installation (ISFSI) Registration for Use of General License Spent Fuel Casks2017-10-19019 October 2017 Independent Spent Fuel Storage Installation (ISFSI) Registration for Use of General License Spent Fuel Casks RNP-RA/17-0068, Response to NRC Request for Additional Information Related to License Amendment Request Regarding Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles2017-09-28028 September 2017 Response to NRC Request for Additional Information Related to License Amendment Request Regarding Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles RNP-RA/17-0037, License Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specifications 3.8.1, AC Sources-Operating and the Use of Load Tap Changers in the Automatic Mode of Operation on the Startup Transformers2017-09-27027 September 2017 License Amendment Request Proposing to Add a Qualified Offsite Circuit to Technical Specifications 3.8.1, AC Sources-Operating and the Use of Load Tap Changers in the Automatic Mode of Operation on the Startup Transformers RNP-RA/17-0043, Relief Request (RR)-12 for Relief from Volumetric/Surface Examination Frequency Requirements of ASME Code Case N-729-42017-09-22022 September 2017 Relief Request (RR)-12 for Relief from Volumetric/Surface Examination Frequency Requirements of ASME Code Case N-729-4 RNP-RA/17-0065, Refueling Outage 30 Steam Generator Tube Inspection Report2017-09-18018 September 2017 Refueling Outage 30 Steam Generator Tube Inspection Report RNP-RA/17-0060, Notification of Change in Licensed Operator Status2017-08-10010 August 2017 Notification of Change in Licensed Operator Status RNP-RA/17-0058, Notification of Change in Licensed Operator Status2017-08-0303 August 2017 Notification of Change in Licensed Operator Status RNP-RA/17-0055, Transmittal of Core Operating Limits Report for Cycle 312017-07-26026 July 2017 Transmittal of Core Operating Limits Report for Cycle 31 RNP-RA/17-0042, Submittal of the PWROG-14048-P, Revision 1, to Satisfy the Regulatory Commitment Related to the Pressurized Water Reactor Internals Program Plan for Aging Management of Reactor Internals2017-06-29029 June 2017 Submittal of the PWROG-14048-P, Revision 1, to Satisfy the Regulatory Commitment Related to the Pressurized Water Reactor Internals Program Plan for Aging Management of Reactor Internals RNP-RA/17-0051, Submittal of Nine Day Inservice Inspection Summary Report2017-06-29029 June 2017 Submittal of Nine Day Inservice Inspection Summary Report RNP-RA/17-0041, Transmittal of Technical Specifications Bases Revisions2017-05-23023 May 2017 Transmittal of Technical Specifications Bases Revisions RNP-RA/17-0038, (Hbrsep), Unit No. 2 - 2016 Annual Radiological Environmental Operating Report2017-05-0909 May 2017 (Hbrsep), Unit No. 2 - 2016 Annual Radiological Environmental Operating Report RNP-RA/17-0034, Modification of Request for Technical Specification Change to Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles (MF9544)2017-05-0202 May 2017 Modification of Request for Technical Specification Change to Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles (MF9544) RNP-RA/17-0036, (Hbrsep), Unit No. 2 - 2016 Annual Radioactive Effluent Release Report and Offsite Dose Calculation Manual, Current Revision 342017-04-25025 April 2017 (Hbrsep), Unit No. 2 - 2016 Annual Radioactive Effluent Release Report and Offsite Dose Calculation Manual, Current Revision 34 RNP-RA/17-0031, Provides Additional Information Regarding License Amendment Request to Adopt Technical Specifications Task Force (TSTF) Traveler 522, Revision 02017-04-20020 April 2017 Provides Additional Information Regarding License Amendment Request to Adopt Technical Specifications Task Force (TSTF) Traveler 522, Revision 0 RNP-RA/17-0033, Flood Hazard Mitigating Strategies Assessment (MSA) Report Submittal2017-04-12012 April 2017 Flood Hazard Mitigating Strategies Assessment (MSA) Report Submittal RNP-RA/17-0014, Resubmittal of Request for Technical Specification Change to Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles2017-04-0303 April 2017 Resubmittal of Request for Technical Specification Change to Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles RNP-RA/17-0028, Submittal of Engineering Calculation in Support of a Request for Technical Specification Change to Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles2017-04-0303 April 2017 Submittal of Engineering Calculation in Support of a Request for Technical Specification Change to Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles RNP-RA/17-0021, Transmittal of Core Operating Limits Report2017-03-13013 March 2017 Transmittal of Core Operating Limits Report RNP-RA/17-0019, Supplemental Submittal to Correct Marked Up Technical Specifications (TS) Pages Transmitted with Application for Technical Specification Task Force (TSTF)-339, Relocate TS Parameters to the COLR Consistent with WCAP-14483, Revision 22017-03-0808 March 2017 Supplemental Submittal to Correct Marked Up Technical Specifications (TS) Pages Transmitted with Application for Technical Specification Task Force (TSTF)-339, Relocate TS Parameters to the COLR Consistent with WCAP-14483, Revision 2 RNP-RA/17-0015, Independent Spent Fuel Storage Installations - Letter Regarding Report of Changes Pursuant to 10 CFR 72.482017-02-22022 February 2017 Independent Spent Fuel Storage Installations - Letter Regarding Report of Changes Pursuant to 10 CFR 72.48 RNP-RA/17-0016, Independent Spent Fuel Storage Installation - Annual Radioactive Effluent Release Report2017-02-22022 February 2017 Independent Spent Fuel Storage Installation - Annual Radioactive Effluent Release Report RNP-RA/17-0015, H.B. Robinson Steam Electric Plant & ISFSIs - Report of Changes Pursuant to 10 CFR 72.482017-02-22022 February 2017 H.B. Robinson Steam Electric Plant & ISFSIs - Report of Changes Pursuant to 10 CFR 72.48 RNP-RA/16-0100, Response to Apparent Violation in NRC Inspection Report 05000261/2016404, EA-16-2272017-01-24024 January 2017 Response to Apparent Violation in NRC Inspection Report 05000261/2016404, EA-16-227 RNP-RA/16-0097, Transmittal Letter for Response to Inspection Report Temporary Instruction 2201/004, Inspection of Implementation of Interim Cyber Security Milestones 1-7, Inspection Report 05000261/20154052016-12-15015 December 2016 Transmittal Letter for Response to Inspection Report Temporary Instruction 2201/004, Inspection of Implementation of Interim Cyber Security Milestones 1-7, Inspection Report 05000261/2015405 RNP-RA/16-0089, Request for Withdrawal of License Amendment Request for Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles2016-11-10010 November 2016 Request for Withdrawal of License Amendment Request for Change Technical Specification Surveillance Requirement Frequencies to Support 24-Month Fuel Cycles RNP-RA/16-0090, Notification of Rescheduled Date for 2017 Emergency Preparedness Graded Exercise2016-11-10010 November 2016 Notification of Rescheduled Date for 2017 Emergency Preparedness Graded Exercise RNP-RA/16-0087, Technical Specifications Section 5.6.6 Post Accident Monitoring Instrumentation Report for Inoperable High Range Containment Area Radiation Monitors2016-10-31031 October 2016 Technical Specifications Section 5.6.6 Post Accident Monitoring Instrumentation Report for Inoperable High Range Containment Area Radiation Monitors RNP-RA/16-0078, Technical Specifications Section 5.6.6, Post Accident Monitoring Instrumentation Report for Inoperable High Range Containment Area Radiation Monitors2016-10-0505 October 2016 Technical Specifications Section 5.6.6, Post Accident Monitoring Instrumentation Report for Inoperable High Range Containment Area Radiation Monitors RNP-RA/16-0079, Response to Request for Additional Information Regarding License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Light Water Reactor Electric Generating Plants.2016-10-0505 October 2016 Response to Request for Additional Information Regarding License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Light Water Reactor Electric Generating Plants. 2021-02-18
[Table view] Category:Licensee Event Report (LER)
MONTHYEARRA-19-0384, LER 20190-001-00 for H.B. Robinson Steam Electric Plant, Unit 2, Turbine Trip/Reactor Trip Due to Main Generator Lockout2019-10-0909 October 2019 LER 20190-001-00 for H.B. Robinson Steam Electric Plant, Unit 2, Turbine Trip/Reactor Trip Due to Main Generator Lockout 05000261/LER-2017-0022017-12-14014 December 2017 Plant Vital Area Security Vulnerability Discovered Without Compensatory Security Measures, LER 17-002-00 for H.B. Robinson, Unit 2, Regarding Plant Vital Area Security Vulnerability Discovered Without Compensatory Security Measures 05000261/LER-2017-0012017-06-0101 June 2017 Auxiliary Feedwater System Actuation During Surveillance Testing, LER 17-001-00 for H.B. Robinson, Unit 2, Regarding Auxiliary Feedwater System Actuation During Surveillance Testing 05000261/LER-2016-0052017-02-22022 February 2017 Reactor Trip and Automatic System Actuation Due to Weather-Related Grid Disturbance, LER 16-005-01 for H. B. Robinson Steam Electric Plant, Unit 2 Regarding Reactor Trip and Automatic System Actuation Due to Weather-Related Grid Disturbance 05000261/LER-2016-0022016-06-13013 June 2016 Unanalyzed Condition Related to Main Steam Line Break Inside Containment, LER 16-002-00 for H.B. Robinson Steam Electric Plant, unit No. 2, Regarding Unanalyzed Condition Related to Main Steam Line Break Inside Containment 05000261/LER-2016-0012016-03-21021 March 2016 Inoperability of Motor-Driven Auxiliary Feedwater Pumps Due to Insufficient Lube Oil Cooling, LER 16-001-00 for H.B. Robinson, Unit 2, Regarding Inoperability of Motor-Driven Auxiliary Feedwater Pumps Due to Insufficient Lube Oil Cooling RNP-RA/11-0057, LER 011-001-00 for H. B. Robinson, Unit 2, Regarding Condition Prohibited by Technical Specifications When Non-Seismic System Was Aligned to Refueling Water Storage Tank Due to Regulatory Requirements Not Adequately Incorporated in Pl2011-06-30030 June 2011 LER 011-001-00 for H. B. Robinson, Unit 2, Regarding Condition Prohibited by Technical Specifications When Non-Seismic System Was Aligned to Refueling Water Storage Tank Due to Regulatory Requirements Not Adequately Incorporated in Plant Do 2019-10-09
[Table view] |
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10 CFR 50.73 Progress Energy Serial: RNP-RA/1 1-0057 JUN 3 o2011 Attn: Document Control Desk United States Nuclear Regulatory Commission Washington, DC 20555-0001 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-261/LICENSE NO. DPR-23 LICENSEE EVENT REPORT NO. 2011-001-00 CONDITION PROHIBITED BY TECHNICAL SPECIFICATIONS WHEN NON-SEISMIC SYSTEM WAS ALIGNED TO REFUELING WATER STORAGE TANK DUE TO REGULATORY REQUIREMENTS NOT ADEQUATELY INCORPORATED IN PLANT DOCUMENTATION Ladies and Gentlemen:
The attached Licensee Event Report is submitted in accordance with the requirements of 10 CFR 50.73. Should you have any questions regarding this matter, please contact Mr. Rich Rogalski at (843) 857-1626.
Sincerely, Thomas S. Cokrove Plant General Manager H. B. Robinson Steam Electric Plant, Unit No. 2 TSC/grs Attachment c: NRC Regional Administrator - Region II NRC Project Manager NRC Resident Inspector Progress Energy Carolinas, Inc.
Robinson Nuclear Plant
'7;-
3581 West Entrance Road Hartsville, SC 29550
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES 1013112013 (10-2010)
Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.
Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the FOIA/Privacy Service Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to infocollects.resource@nrc.gov, and to the Desk Officer, Office of (See reverse for required number of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and digits/characters for each block) Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE H. B. Robinson Steam Electric Plant, Unit No. 2 05000261 1 OF 3
- 4. TITLE Condition Prohibited by Technical Specifications When Non-Seismic System was Aligned to Refueling Water Storage Tank due to Regulatory Requirements not Adequately Incorporated in Plant Documentation
- 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED FACILITY NAME DOCKET NUMBER DAY YEAR 05000 YEAR SEQUENTIAL REV MONTH MONTH DAY YEAR NUMBER NO 05000 FACILITY NAME DOCKET NUMBER 05 04 2011 201111. - 001 - 00 07 05 2011 THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 05000
- 9. OPERATING MODE r0 20.2201(b) El 20.2203(a)(3)(i) El 50.73(a)(2)(i)(C) Ml 50.73(a)(2)(vii) nl 20.2201(d) El 20.2203(a)(3)(ii) El 50.73(a)(2)(ii)(A) -- 50.73(a)(2)(viii)(A) 1 El 20.2203(a)(1) El 20.2203(a)(4) El 50.73(a)(2)(ii)(B) fl 50.73(a)(2)(viii)(B)
_ 20.2203(a)(2)(i) El 50.36(c)(1)(i)(A) El 50.73(a)(2)(iii) E- 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 0 20.2203(a)(2)(ii) El 50.36(c)(1)(ii)(A) El 50.73(a)(2)(iv)(A) [] 50.73(a)(2)(x)
[] 20.2203(a)(2)(iii) El 50.36(c)(2) El 50.73(a)(2)(v)(A) r] 73.71 (a)(4) 100% El 20.2203(a)(2)(iv) El 50.46(a)(3)(ii) El 50.73(a)(2)(v)(B) f 73.71 (a)(5) fl 20.2203(a)(2)(v) El 50.73(a)(2)(i)(A) El 50.73(a)(2)(v)(C) rl OTHER Specify in Abstract below SEl 20.2203(a)(2)(vi) [ 50.73(a)(2)(i)(B) El 50.73(a)(2)(v)(D) or in NRC Form 366A
- 12. LICENSEE CONTACT FOR THIS LER I
- 14. SUPPLEMENTAL REPORT EXPECTED El YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
ABSTRACT (Limit to 1400 spaces. i.e.. aDDroximatelv 15 sinale-soaced tvoewritten lines)
On May 4, 2011, with H. B. Robinson Steam Electric Plant (HBRSEP), Unit No. 2, in Mode 1 at 100%
power, it was determined that over the last 40 years, HBRSEP, Unit No. 2, periodically performed cleanup of the Refueling Water Storage Tank (RWST) by aligning the non-seismically qualified refueling water purification system to the safety related and seismically qualified RWST without recognizing that the action rendered the RWST inoperable. As a result, on multiple occasions, the RWST was inoperable for a period longer than allowed by Technical Specification (TS) Limiting Condition for Operation 3.5.4, Emergency Core Cooling Systems - Refueling Water Storage Tank.
The cause of this event was that regulatory requirements for the separation of seismically qualified and non-qualified systems, structures, and components were not adequately incorporated into the Design Basis Document (DBD) and Updated Final Safety Analysis Report (UFSAR).
Administrative controls have been put in place on the alignment restrictions for piping that could affect the operability of the RWST. Additional corrective actions planned include DBD and UFSAR changes and modifications of applicable plant procedures.
The condition described in this Licensee Event Report is reportable in accordance with 10 CFR 50.73(a)(2)(i)(B), any operation or condition which was prohibited by the plant's Technical Specifications.
NRC FORM 366 (10-2010)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGE YEAR NUMBER SEQUENTIAL REV.
NO. 2 OF 3 H. B. Robinson Steam Electric Plant, Unit No. 2 05000261 2011 - 001 - 00 NARRATIVE
- 1. DESCRIPTION OF EVENT On May 4, 2011, with H. B. Robinson Steam Electric Plant (HBRSEP), Unit No. 2, in Mode 1 at 100%
power, it was determined that over the last 40 years HBRSEP, Unit No. 2, periodically performed cleanup of the Refueling Water Storage Tank (RWST) [TK] by aligning the non-seismically qualified refueling water purification system [KH] to the safety related and seismically qualified RWST without recognizing that the action rendered the RWST inoperable. As a result, on multiple occasions, the RWST was inoperable for a period longer than allowed by Technical Specification (TS) Limiting Condition for Operation (LCO) 3.5.4, Emergency Core Cooling Systems - Refueling Water Storage Tank, Condition B.
TS LCO 3.5.4, Action B, requires that, with the RWST inoperable for reasons other than Condition A, restore the RWST to Operable status within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> or be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and Mode 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />, in accordance with Condition C. (Condition A pertains to inoperability associated with RWST boron concentration and temperature limits.)
I1. CAUSE OF EVENT This event was investigated using the HBRSEP, Unit No. 2, Corrective Action Program (CAP) and is documented in NCR 463557.
The NCR 463557 investigation concluded that the regulatory requirements for the separation of seismically qualified and non-qualified systems, structures, and components were not adequately incorporated into the Design Basis Document and Updated Final Safety Analysis Report (UFSAR).
This is a historical condition that has existed for the life of the plant.
Ill. ANALYSIS OF EVENT The HBRSEP, Unit No. 2, original plant design included a refueling water purification loop, consisting of a refueling water purification pump, filter, and demineralizer. The loop can be aligned to filter and demineralize either the spent fuel pool or the RWST. The refueling water purification loop is non-seismically qualified. It is normally isolated from the RWST by manual isolation valves which are within the seismically qualified boundary of the RWST.
As stated in the NCR 463557 investigation, for the first forty years of plant operation, HBRSEP, Unit No. 2, periodically aligned the refueling water purification loop to the RWST and operated the system to maintain the water quality of the RWST. This had been done in both on-line and outage conditions.
During the last three years, the purification loop was in service aligned to the RWST while HBRSEP, Unit No. 2, was on-line for periods of less than 1 day to as many as 161 days.
NCR 463557 was initiated in May 2011. The investigation concluded that the regulatory requirements for the separation of seismically qualified and non-qualified systems, structures, and components were not adequately incorporated into the Design Basis Document and Updated Final Safety Analysis Report (UFSAR).
NRC FORM 366A (10-2010)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGE SEQUENTIAL REV.
YEAR NUMBER NO. 3 OF 3 H. B. Robinson Steam Electric Plant, Unit No. 2 05000261 2011 - 001 - 00 NARRATIVE IV. SAFETY SIGNIFICANCE The risk impact of having the RWST aligned for purification has been evaluated and determined to be of low risk impact (<5E-07). This analysis takes into consideration the impact of internal flooding due to a pipe break, as well as the increase in risk due to a seismic event. The result of the analysis was based on having the non-seismic refueling water purification loop in service aligned to the RWST with the plant on-line for a conservative estimate of approximately 5000 hours0.0579 days <br />1.389 hours <br />0.00827 weeks <br />0.0019 months <br /> per year. The analysis conservatively assumed that the refueling water purification path will fail and drain the RWST under a range of seismic events. Also, operator actions are conservatively not credited after a break in the purification flowpath. Even with these conservative assumptions, having the RWST in recirculation mode while the plant is at power results in a very small increase in risk due to seismic events.
The condition described in this Licensee Event Report is reportable in accordance with 10 CFR 50.73(a)(2)(i)(B), any operation or condition which was prohibited by the plant's Technical Specifications.
V. CORRECTIVE ACTIONS Completed Corrective Actions:
- Administrative controls have been put in place to provide guidance for Operations on alignment restrictions for piping that could affect the operability of the RWST.
Planned Corrective Actions:
- Applicable Operations procedures will be revised to restrict alignment of the refueling water purification loop to periods when RWST operability is not required.
- Applicable sections of the UFSAR and Design Basis Documentation will be revised to include restrictions on the operating modes when the purification loop is allowed to be used to purify the RWST.
VI. PREVIOUS SIMILAR EVENTS:
Licensee Event Reports (LERs) for HBRSEP, Unit No. 2, were reviewed from the past 5 years. No similar events were identified.
NRC FORM 366A (10-2010)