ML11250A100
| ML11250A100 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 11/10/2011 |
| From: | Jaffe D H Plant Licensing Branch II |
| To: | Ajluni M J Southern Nuclear Operating Co |
| Jaffe D H, NRR/DORL/LPL2-1, 415-1439 | |
| References | |
| TAC ME6144, TAC ME6145 | |
| Download: ML11250A100 (20) | |
Text
UNITED NUCLEAR REGULATORY WASHINGTON, D.C. 20555-0001 November 10, 2011 Mr. M. J. Ajluni Nuclear Licensing Director Southern Nuclear Operating Company, Inc. 40 Inverness Center Parkway Post Office Box 1295, Bin -038 Birmingham, AL 35201-1295 VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2, ISSUANCE OF AMENDMENTS REGARDING REACTOR COOLANT SYSTEM (RCS) LEAKAGE DETECTION INSTRUMENTATION (TAC NOS. ME6144 AND ME6145)
Dear Mr. Ajluni:
The Nuclear Regulatory Commission has issued the enclosed Amendment No. 164 to Renewed Facility Operating License NPF-68 and Amendment No. 146 to Renewed Facility Operating License NPF-81 for the Vogtle Electric Generating Plant, Units 1 and 2, respectively.
The amendments consist of changes to the License and Technical Specifications (TSs) in response to your application dated April 29, 2011. The amendments revise TS 3.4.15, "RCS Leakage Detection Instrumentation" to define a new time limit for restoring inoperable RCS leakage detection instrument to operable status and establish alternate methods of monitoring RCS leakage when one or more required monitors are inoperable.
This revision is consistent with the IndustryfTechnical Specification Task Force (TSTF) standard technical specification traveler TSTF-513-A, "Revise PWR [pressurized water reactor] Operability Requirements and Actions for RCS Leakage [Detection]
Instrumentation."
M. Ajluni -A copy of the related Safety Evaluation is also enclosed.
A Notice of Issuance will be incfuded in the Commission's biweekly Federal Register notice. Sincerely, David H. Jaffe, Senior Project Plant Licensing Branch Division of Operating Reactor Office of Nuclear Reactor Docket Nos. 50-424 and
Enclosures:
- 1. Amendment No. 164 to 2. Amendment No. 146 to 3. Safety Evaluation cc w/encls: Distribution via Listserv UNITED NUCLEAR REGULATORY WASHINGTON, D.C. 20555-0001 SOUTHERN NUCLEAR OPERATING COMPANY. INC. GEORGIA POWER COMPANY OGLETHORPE POWER CORPORATION MUNICIPAL ELECTRIC AUTHORITY OF GEORGIA CITY OF DALTON. GEORGIA DOCKET NO. 50-424 VOGTLE ELECTRIC GENERATING PLANT. UNIT 1 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 164 Renewed License No. NPF-68 The Nuclear Regulatory Commission (the Commission) has found that: The application for amendment to the Vogtle Electric Generating Plant, Unit 1 (the facility)
Renewed Facility Operating License No. NPF-68 filed by the Southern Nuclear Operating Company, Inc. (the licensee), acting for itself, Georgia Power Company, Oglethorpe Power Corporation, Municipal Electric Authority of Georgia, and City of Dalton, Georgia (the owners), dated April 29, 2011, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations as set forth in 10 CFR Chapter I; The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations set forth in 10 CFR Chapter I; The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.
-Accordingly, the license is hereby amended by page changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-68 is hereby amended to read as follows: Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 164 , and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. Southern Nuclear shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan. This license amendment is effective as of its date of issuance and shall be implemented within 60 days of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION Gloria Kulesa, Chief Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to License No. NPF-68 and the Technical Specifications Date of Issuance:
November 10, 2011 UNITED NUCLEAR REGULATORY WASHINGTON, D.C. 20555-0001 SOUTHERN NUCLEAR OPERATING COMPANY, GEORGIA POWER OGLETHORPE POWER MUNICIPAL ELECTRIC AUTHORITY OF CITY OF DALTON, DOCKET NO. VOGTLE ELECTRIC GENERATING PLANT, UNIT AMENDMENT TO RENEWED FACILITY OPERATING Amendment No. 146 Renewed License No. NPF-81 The Nuclear Regulatory Commission (the Commission) has found that: The application for amendment to the Vogtle Electric Generating Plant, Unit 2 (the facility)
Renewed Facility Operating License No. NPF-81 filed by the Southern Nuclear Operating Company, Inc. (the licensee), acting for itself, Georgia Power Company Oglethorpe Power Corporation, Municipal Electric Authority of Georgia, and City of Dalton, Georgia (the owners), dated April 29, 2011, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations as set forth in 10 CFR Chapter I; The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations set forth in 10 CFR Chapter I; The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.
-Accordingly, the license is hereby amended by page changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-81 is hereby amended to read as follows: Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 146 ,and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. Southern Nuclear shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan. This license amendment is effective as of its date of issuance and shall be implemented within 60 days of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION Gloria Kulesa, Chief Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to License No. NPF-81 and the Technical Specifications Date of Issuance:
November 10. 2011
TO LICENSE AMENDMENT NO. RENEWED FACILITY OPERATING LICENSE NO. DOCKET NO. TO LICENSE AMENDMENT NO. RENEWED FACILITY OPERATING LICENSE NO. DOCKET NO. Replace the following pages of the Licenses and the Appendix A Technical Specifications (TSs) with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change. Remove Pages Insert Pages License License License No. NPF-68, page 4 License No. NPF-68, page 4 License No. NPF-81, page 3 License No. NPF-81, page 3 TSs 3.4.15-3 3.4.15-4 3.4.15-5 Maximum Power Level Southern Nuclear is authorized to operate the facility at reactor core power levels not in excess of 3625.6 megawatts thermal (100 percent power) in accordance with the conditions specified herein. Technical Specifications and Environmental Protection Plan The Technical contained in Appendix A, as revised through Amendment No. 164 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. Southern Nuclear shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan. Southern Nuclear Operating Company shall be capable of establishing containment hydrogen monitoring within 90 minutes of initiating safety injection following a loss of coolant accident. Deleted Deleted Deleted Deleted Deleted Deleted Mitigation Strategy License Condition The licensee shall develop and maintain strategies for addressing large fires and explosions and that include the following key areas: Fire fighting response strategy with the following elements: Pre-defined coordinated fire response strategy and guidance Assessment of mutual aid fire fighting assets DeSignated staging areas for equipment and materials Command and control Training of response personnel Operations to mitigate fuel damage considering the following: Protection and use of personnel assets Communications Minimizing fire spread Procedures for implementing integrated fire response strategy Identification of readily-available pre-staged equipment Training on integrated fire response strategy Renewed Operating License No. NPF-68 Amendment No. 164
-Georgia Power Company, Oglethorpe Power Corporation, Municipal Electric Authority of Georgia, and City of Dalton, Georgia, pursuant to the Act and 10 CFR Part 50, to possess but not operate the facility at the designated location in Burke County, Georgia, in accordance with the procedures and limitations set forth in this license; Southern Nuclear, pursuant to the Act and 10 CFR Part 70, to receive, possess, and use at any time special nuclear material as reactor fuel, in accordance with the limitations for storage and amounts required for reactor operation, as described in the Final Safety Analysis Report, as supplemented and amended; Southern Nuclear, pursuant to the Act and 10 CFR Parts 30,40. and 70 to receive, possess, and use at any time any byproduct, source and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; Southern Nuclear, pursuant to the Act and 10 CFR Parts 30, 40, and 70, to receive, possess, and use in amounts as required any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; Southern Nuclear, pursuant to the Act and 10 CFR Parts 30, 40, and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility authorized herein. This license shall be deemed to contain and is subject to the conditions specified in the Commission's regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect, and is subject to the additional conditions specified or incorporated below. Maximum Power Level Southern Nuclear is authorized to operate the facility at reactor core power levels not in excess of 3625.6 megawatts thermal (100 percent power) in accordance with the conditions specified herein. Technical Specifications and Environmental Protection Plan The Technical Soecifications contained in Appendix A. as revised through Amendment No. 146 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. Southern Nuclear shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan. The Surveillance Requirements (SRs) contained in the Appendix A Technical Specifications and listed below are not required to be performed immediately upon implementation of Amendment No. 74. The SRs listed below shall be Renewed Operating License NPF-81 Amendment No. 146 RCS Leakage Detection Instrumentation 3.4.15 ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME E. Required containment atmosphere radioactivity monitor inoperable.
AND Required containment air cooler condensate flow rate monitor inoperable.
E.1 OR E.2 Restore required 30 days containment atmosphere radioactivity monitor to OPERABLE status. Restore required 30 days containment air cooler condensate flow rate monitor to OPERABLE status. ---------------N OTE Only applicable when a containment atmosphere gaseous radiation monitor is the only OPERABLE monitor.
F. Required containment sump monitors inoperable.
F.1 AND F.2.1 Analyze grab samples of Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> the containment atmosphere.
Restore required 7 days containment sump monitors to OPERABLE status. AND OR Required containment air cooler condensate 1l0w rate monitor inoperable.
F.2.2 Restore required 7 days containment air cooler condensate flow rate monitor to OPERABLE status. G. Required Action and associated Completion Time not met. G.1 AND Be in MODE 3. 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> G.2 Be in MODE 5. 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> (continued)
Vogtle Units 1 and 2 Amendment No.164 (Unit 1) Amendment No.146 (Unit 2)
RCS Leakage Detection Instrumentation 3.4.15 ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME H. All required leakage H.1 Enter LCO 3.0.3. Immediately detection systems inoperable.
SURVEILLANCE SURVEILLANCE FREQUENCY SR 3.4.15.1 Perform CHANNEL CHECK of containment normal sumps level and reactor cavity sump level monitors.
I n accordance with the Surveillance Frequency Control Program SR 3.4.15.2 Perform CHANNEL CHECK of the required containment atmosphere radioactivity monitor. In accordance with the Surveillance Frequency Control Program SR 3.4.15.3 Perform COT of the required containment atmosphere radioactivity monitor. In accordance with the Surveillance Frequency Control Program SR 3.4.15.4 Perform CHANNEL CALIBRATION of the containment sump monitors.
In accordance with the Surveillance Frequency Control Program SR 3.4.15.5 Perform CHANNEL CALIBRATION of the required containment atmosphere radioactivity monitor. In accordance with the Surveillance Frequency Control Program (continued)
Vogtle Units 1 and 2 Amendment No. 164 (Unit 1) Amendment No. 146 (Unit 2)
RCS Leakage Detection Instrumentation 3.4.15 SR Perform CHANNEL CALIBRATION of the required containment air cooler condensate flow rate monitor.
In accordance with the Surveillance Frequency Control Program Vogtle Units 1 and 2 3.4.15-5 Amendment No. 164 (Unit 1) Amendment No. 146 (Unit 2)
UNITED NUCLEAR REGULATORY WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 164 TO RENEWED FACILITY OPERATING LICENSE NPF-68 AND AMENDMENT NO. 146 TO RENEWED FACILITY OPERATING LICENSE NPF-81 REQUIREMENTS AND ACTIONS FOR RCS LEAKAGE INSTRUMENTATION SOUTHERN NUCLEAR OPERATING COMPANY, INC. VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2 DOCKET NOS. 50-424 AND 50-425 TAC NOS. ME6144 AND ME6145
1.0 INTRODUCTION
By letter dated April 29, 2011 (Agencywide Documents Access and Management System (ADAMS), Accession No. ML 111220091), Southern Nuclear Operating Company (SNC, the licensee) proposed changes to the Technical Specifications (TSs) for the Vogtle Electric Generating Plant, Units 1 and 2 (VEGP). The proposed changes revise the TSs to define a new time limit for restoring inoperable Reactor Coolant System (RCS) leakage detection instrumentation to operable status; establish alternate methods of monitoring RCS leakage when one or more required monitors are inoperable; and make TS Bases changes which reflect the contents of the facility design basis related to operability of the RCS leakage detection instrumentation.
The licensee stated that the license amendment request (LAR) is consistent with Nuclear Regulatory Commission (NRC)-approved Revision 3 to Technical Specification Task Force (TSTF) Standard Technical Specification (STS) Change Traveler, TSTF-513, "Revise PWR [pressurized water reactor] Operability Requirements and Actions for RCS Leakage [detection]
Instrumentation." The availability of this TS improvement was announced in the Federal Register (FR) on January 3, 2011 (76 FR 189) as part of the consolidated line item improvement process (CLlIP). The licensee proposed plant-specific deviations from the applicable TS changes described in TSTF-513, Revision 3. These deviations are discussed in the licensee's Technical Evaluation included in the license amendment request. The deviations are consistent with the intent of TSTF-513, Revision 3 and do not affect the applicability of the no significant hazards consideration determination published in the FR as part of the CLlIP.
-2 2.0 REGULATORY The NRC's regulatory requirements related to the content of the TSs are contained in Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 50.36. Paragraph (c)(2)(i) of 10 CFR 50.36 states that limiting conditions for operation (LCOs) are the lowest functional capability or performance levels of equipment required for safe operation of the facility.
Paragraph (c)(2)(ii) of 10 CFR 50.36 lists four criteria for determining whether particular items are required to be included in the TS LCOs. The first criterion applies to installed instrumentation that is used to detect and indicate, in the control room, a significant abnormal degradation of the reactor coolant pressure boundary (RCPB). As described in the FR Notice associated with this regulation (60 FR 36953, July 16, 1995), the scope of the TSs includes two general classes of technical matters: (1) those related to prevention of accidents, and (2) those related to mitigation of the consequences of accidents.
Criterion 1 addresses systems and process variables that alert the operator to a situation when accident initiation is more likely, and supports the first of these two general classes of technical matters, which are included in the TSs. As specified in paragraph (c)(2)(i) of 10 CFR 50.36, when an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TS until the condition can be met. The NRC's guidance for the format and content of PWR TSs can be found in NUREG-1431, Revision 3, "Standard Technical Specifications Westinghouse Plants." STS 3.4.15, "RCS Leakage Detection Instrumentation," and contains the guidance specific to the RCS leakage detection instrumentation for PWRs. The STS Bases provide a summary statement of the reasons for the STSs. The Bases for STS 3.4.15 contained in NUREG-1431, Revision 3 provide background information, the applicable safety analyses, a description of the LCO, the applicability for the RCS leakage detection instrumentation TS, and describe the Actions and Surveillance Requirements.
The TS Bases provide the purpose or reason for the TSs, which are derived from the analyses and evaluation included in the safety analysis report, and for these Specifications, the RCS leakage detection instrumentation design assumptions and licensing basis for the plant. As stated in NRC Information Notice (IN) 2005-24, "Non conservatism in Leakage Detection Sensitivity" (ADAMS Accession No. ML051780073), the reactor coolant activity assumptions for containment atmosphere gaseous radioactivity monitors may be nonconservative.
This means the monitors may not be able to detect a one-gallon-per-minute (gpm) leak within 'I hour under all likely operating conditions.
The issue described in IN 2005-24 has raised questions regarding the operability requirements for containment atmosphere gaseous radioactivity monitors.
TSTF-513, Revision 3, revises the TS Bases to reflect the proposed TS changes and more accurately describe the contents of the facility design basis related to operability of the RCS leakage detection instrumentation.
Part of the TS Bases change revises the specified safety function of the RCS leakage detection monitors to specify the required instrument sensitivity level. In addition, TSTF-513, Revision 3, includes revisions to TS Actions for RCS leakage detection instrumentation to establish limits for operation during conditions of reduced monitoring sensitivity because of inoperable RCS leakage detection instrumentation.
The regulation at 10 CFR Part 50, Appendix A, General Design Criterion (GDG) 30, "Quality of reactor coolant pressure boundary," requires means for detecting and, to the extent practical,
-identifying the location of the source of RCS leakage. Regulatory Guide (RG) 1.45, Revision 0, "Reactor Coolant Pressure Boundary Leakage Detection Systems," May 1973 (ADAMS Accession No. ML003740113), describes acceptable methods of implementing the GDC 30 requirements with regard to the selection of leakage detection systems for the RCPB. RG 1.45, Revision 0, Regulatory Position C.2, states that "LeakClge to the primary reactor containment from unidentified sources should be collected and the flow rate monitored with an accuracy of one gallon per minute (gpm) or better." RG 1.45, Revision 0, Regulatory Position C.3 states: At least three separate detection methods should be employed and two of these methods should be (1) sump level and flow monitoring and (2) airborne particulate radioactivity monitoring.
The third method may be selected from the following:
- a. monitoring of condensate flow rate from air coolers [or] b. monitoring of airborne gaseous radioactivity.
Humidity, temperature, or pressure monitoring of the containment atmosphere should be considered as alarms or indirect indication of leakage to the containment.
RG 1.45, Revision 0, Regulatory Position C.5 states, 'The sensitivity and response time of each leakage detection system in regulatory position 3 above employed for unidentified leakage should be adequate to detect a leakage rate, or its equivalent, of one gpm in less than one hour." RG 1.45, Revision 0, states, "In analyzing the sensitivity of leak detection systems using airborne particulate or gaseous radioactivity, a realistic primary coolant radioactivity concentration assumption should be used. The expected values used in the plant environmental report would be acceptable." The appropriate sensitivity of a plant's containment atmosphere gaseous radioactivity monitors is dependent on the design assumptions and the plant-specific licensing basis as described in the plant's final safety analysis report (FSAR). The NRC staff's approval of the use of expected primary coolant radioactivity concentration values used in the environmental report creates a potential licensing conflict when a licensee is able to achieve and maintain primary coolant radioactivity concentration values lower than the value assumed in the environmental report. RG 1.45, Revision 1, "Guidance on Monitoring and Responding to Reactor Coolant System Leakage," was issued in May 2008. RG 1.45, Revision 1 (ADAMS Accession No. ML073200271), describes methods for implementing GDC 30 requirements that are different from those in RG 1.45, Revision 0, and was developed and issued to support new reactor licensing.
Revision 1 allows that having two TS leakage detection methods capable of detecting a one-gpm leak within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> provides adequate leakage detection capability from a safety perspective.
It recommends that other potential indicators (including the gaseous radiation monitors) be maintained even though they may not have the same detection capability.
These indicators, in effect, provide additional defense-in-depth.
The regulation in GDC 4 of Appendix A to 10 CFR Part 50, "Environmental and dynamic effects design bases," requires structures, systems, and components important to safety to be designed to accommodate the effects of and to be compatible with the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents.
GDC 4 allows the use of leak before break (LBB) technology to exclude dynamic effects of pipe ruptures in the design bases when analyses reviewed and approved by the Commission demonstrate that the probability of a fluid system piping rupture is extremely low under conditions consistent with the design basis for the piping. VEGP compliance with GDC 30 is discussed in FSAR Section 3.1.4, "Fluid Systems." With respect to RCS leakage detection, FSAR Section 3.1.4 states: Criterion 30 -Quality of Reactor Coolant Pressure Boundary "Components which are part of the reactor coolant pressure boundary shall be designed, fabricated, erected, and tested to the highest quality standards practical.
Means shall be provided for detecting and, to the extent practical, identifying the location of the source of reactor coolant leakage." Discussion All RCS components are designed, fabricated, inspected, and tested in conformance with the ASME Boiler and Pressure Vessel Code,Section III. All balance of plant components are classified according to Regulatory Guide 1.26, and all nuclear steam supply system (NSSS) components are classified according to ANSI N18.2-1973 and ANSI N18.2A-1975 (which is an acceptable alternative to Regulatory Guide 1.26) and are accorded all the quality measures appropriate to these classifications.
The design bases and evaluations of the RCS are discussed in chapter 5. VEGP's Updated Final Safety Analysis Report Section 5.2.5.1 "Design Bases" states: The leak detection systems are designed in accordance with the requirements of 10 CFR 50 and the general design criterion 30 to provide a means of detecting and, to the extent practical, identifying the source of the reactor coolant leakage. The systems conform with Regulatory Guide 1.45. Main systems that monitor the environmental condition of the containment include the sump level monitoring system, the airborne particulate radioactivity monitoring systems, and the containment fan cooler condensate measuring system. In addition to the above systems, the humidity, temperature, pressure, and radiogas monitors provide indirect indication of leakage to the containment.
3.0 TECHNICAL EVALUATION In adopting the changes to the TSs included in TSTF-513, Revision 3, the licensee proposed to revise TS 3.4.15, "RCS Leakage Detection Instrumentation" Conditions and Required Actions. The licensee proposed adding new Condition F to TS 3.4.15. New Condition F would be applicable when the containment atmosphere gaseous radioactivity monitor is the only operable RCS leakage detection monitor. This new Condition is necessary because improved fuel integrity and the resulting lower primary coolant radioactivity concentration affects a plant's containment atmosphere gaseous radioactivity monitor to a greater extent than other monitors.
The proposed Required Actions for new Condition F require the licensee to analyze grab samples of the containment atmosphere once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and restore the required containment sump monitor to operable status within 7 days, or analyze grab samples of the containment atmosphere once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and restore the containment air cooler condensate flow rate monitor to operable status within 7 days. These actions are in addition to the Required Actions of Condition A, which requires performing an RCS mass balance once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
-5 The NRC staff determined that the proposed Condition F is more restrictive than the current requirement because the current Condition that would apply to the situation when the containment atmosphere gaseous radioactivity monitor is the only operable RCS leakage detection monitor would allow the licensee 30 days to restore the inoperable monitors to operable status. The proposed Actions and Completion Times are adequate because the grab samples combined with the more frequent RCS mass balances will provide an alternate method of monitoring RCS leakage when the containment atmosphere gaseous radioactivity monitor is the only operable RCS leakage detection monitor and the 12-hour interval is sufficient to detect increasing RCS leakage long before a piping flaw could progress to a catastrophic failure of the primary RCPB. Allowing 7 days to restore another RCS leakage monitor to operable status is reasonable given the diverse methods employed in the Required Actions to detect an RCS leak and the low probability of a large RCS leak during this period. Proposed Condition F is conservative relative to the STSs, sufficiently alerts the operating staff, provides a comparable ability to detect RCS leakage, and provides time intervals that are reasonable.
Therefore, the NRC staff determined that proposed Condition F provides an adequate assurance of safety when judged against current regulatory standards.
Certain American Society of Mechanical Engineers (ASME) Code Class 1 piping systems in VEGP have been approved by the NRC for LBB. The basic concept of LBB is that certain piping material has sufficient fracture toughness (i.e., ductility) to resist rapid flaw propagation; thereby minimizing the probability of a pipe rupture. The licensee has evaluated postulated flaws in RCS loop piping and determined the piping has sufficient fracture toughness that the postulated flaw would not lead to pipe rupture and potential damage to adjacent safety-related systems, structures and components before the plant could be placed in a safe, shutdown condition.
The NRC staff has previously reviewed and approved these plant-specific LBB analyses.
Before remotely approaching a pipe rupture, the postulated flaw would lead to limited but detectable leakage, which would be identified by the leak detection systems in time for the operator to take action. The NRC staff previously addressed concerns that LBB depends on erroneous leak rate measurements in the final rule making for use of LBB technology.
In addressing the concerns, it was noted in (51 FR 12502) that: ... one criterion for application of leak-before-break is that postulated flaw sizes be large enough so that the leakage is about ten times the leak detection capability, and that this flaw be stable even if earthquake loads are applied to the pipe in addition to the normal operating loads. This margin of a factor of ten is more than ample to account for uncertainties in both leakage rate calculations and leak detection capabilities.
Additional sensitivity studies reported by Lawrence Livermore National Laboratory in NUREG/CR-2189, dated September 1981, entitled "Probability of Pipe Fracture in the Primary Coolant Loop of a PWR Plant" indicate that even in the absence of leak detection, the probability of pipe ruptures in PWR primary coolant loop piping is sufficiently low to warrant exclusion of these events from the design basis. The proposed actions for inoperable RCS leakage detection instrumentation maintain sufficient continuity, redundancy, and diversity of leakage detection capability that an extremely low probability of undetected leakage leading to pipe rupture is maintained.
This extremely low probability of pipe rupture continues to satisfy the basis for acceptability of LBB in GOC 4. The licensee proposes minor changes to ensure continuity of the TS format. These changes re-Ietter current Condition F, which applies when the required action and the associated completion time are not satisfied, to Condition G, and current Condition G, which applies when all required leakage detection systems are inoperable, to Condition H. Similar changes were made to the associated Required Actions. The NRC staff determined that these changes are editorial, and therefore acceptable.
The associated TS Bases submitted with the licensee's proposed revision for TS 3.4.15 reflect the proposed TS changes and more accurately describe the contents of the facility design basis related to operability of the RCS leakage detection instrumentation and reflect the proposed TS changes. The proposed TS Bases changes related to the operability of the RCS leakage detection instrumentation are acceptable because they provide background information, the applicable safety analyses, a description of the LCO, and the applicability for the RCS leakage detection instrumentation TS and are consistent with the design basis of the facility.
These instruments satisfy Criterion 1 of 10 CFR 50.36( c)(2)(ii) in that they are installed instrumentation that is used to detect, and indicate in the control room, a significant abnormal degradation of the RCPS. The licensee proposed a minor variation from the TS changes described in TSTF 513, Rev. 3. As stated in TSTF-513, "In several locations in all three NUREGs, the specifications incorrectly refer to a "required" containment sump monitor or "required" containment air cooler flow rate monitor when the LCO does not provide for more than one monitor." In TSTF-513 the word "required" is deleted from TSTF-513 Condition C which corresponds to VEGP TS 3.4.15 Condition O. However, the word "required" is appropriate in the VEGP Condition 0, as there are multiple ways to meet the VEGP LCO requirement.
Therefore, the word "required" is not deleted from the VEGP Condition O. The NRC staff finds this variation consistent with the intent of TSTF-513.
The NRC staff evaluated the licensee's proposed changes against the applicable regulatory requirements listed in Section 2 of this SE. The NRC staff also compared the proposed changes to the changes made to the STSs by TSTF-513, Revision 3. The NRC staff determined that all the proposed changes afford adequate assurance of safety when judged against current regulatory standards.
Therefore, the NRC staff finds the proposed changes acceptable.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Georgia State official was notified on October 20, 2011, of the proposed issuance of the amendments.
The State official had no comments.
5.0 ENVIRONMENTAL CONSIOERA TION The amendments change a requirement with respect to the installation or use of facility components located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendments involve no significant increase in the amounts and no significant change in the types of any effluents that may be released offsite and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (76 FR 34768). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR
-7 51.22(c}(9}.
Pursuant to 10 CFR 51.22(b} no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments. CONCLUSION The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public. REFERENCES Southern Nuclear Operating Company, Inc., Vogtle Electric Generating Plant Units 1 and 2, "License Amendment Request to Adopt TSTF-513-A, Revision 3 'Revise PWR Operability Requirements and Actions for RCS Leakage,'" April 29, 2011 (ADAMS Accession No. ML 111220091) Submittal of TSTF-513, Revision 3 (ADAMS Accession No. ML 102360355) Notice of Availability published in the FR on January 3, 2011 (ADAMS Accession No. ML 101340267)
Principal Contributors:
M. Singletary M. Hamm Date: November 10,2011 M. Ajluni -2 A copy of the related Safety Evaluation is also enclosed.
A Notice of Issuance will be included in the Commission's biweekly Federal Register notice. Docket Nos. 50-424 and 50-425
Enclosures:
- 1. Amendment No. 164 to NPF-68 2. Amendment No. 146 to NPF-81 3. Safety Evaluation cc w/encls: Distribution via Listserv DISTRIBUTION:
Public LPL2-1 RtF RidsAcrsAcnw_MailCTR Resource RidsOgcRp Resource RidsNrrDorlLpl2-1 Resource Sincerely, IRA! David H. Jaffe, Senior Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensil1g Office of Nuclear Reactor Regulation RidsNrrDssSbpb Resource RidsNrrPMVogtie Resource RidsNrrLAMO'Brien Resource RidsNrrDirsltsb Resource RidsNrrDorlDpr Resource RidsRgn2MailCenter Resource MSingletary, NRR MHamm, NRR