ML13311B481
| ML13311B481 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood  |
| Issue date: | 07/21/2014 |
| From: | Joel Wiebe Plant Licensing Branch III |
| To: | Pacilio M Exelon Generation Co, Exelon Nuclear |
| Joel Wiebe, NRR/DORL 415-6606 | |
| References | |
| TAC ME9134, TAC MF9135, TAC MF9136, TAC MF9137 | |
| Download: ML13311B481 (24) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 July 21, 2014 Mr. Michael J. Pacilio Senior Vice President Exelon Generation Company, LLC President and Chief Nuclear Officer (CNO)
Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
BRAIDWOOD STATION, UNITS 1 AND 2, AND BYRON STATION, UNIT NOS. 1 AND 2 - ISSUANCE OF AMENDMENTS TO REVISE TECHNICAL SPECIFICATIONS SECTION 3.5.3 (TAC NOS. MF9134, MF9135, MF9136, AND MF9137)
Dear Mr. Pacilio:
The U.S. Nuclear Regulatory Commission has issued the enclosed Amendment No. 176 to Facility Operating License No. NPF-72 and Amendment No. 176 to Facility Operating License No. NPF-77 for the Braidwood Station, Units 1 and 2, respectively, and Amendment No. 182 to Facility Operating License No. NPF-37 and Amendment No. 182 to Facility Operating License No. NPF-66 for the Byron Station, Unit Nos. 1 and 2, respectivey. The amendments are in response to your application dated July 23, 2012 (Agency Documents Access and Management System (ADAMS) Accession No. ML12206A057), as supplemented by letter dated May 1, 2013 (ADAMS Accession No. ML13122A046).
A copy of the Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.
oel S. Wiebe, Senior Project Manager lant Licensing 111-2 and Planning and Analysis Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN 50-456, STN 50-457, STN 50-454 and STN 50-455
Enclosures:
- 1. Amendment No. 176 to NPF-72
- 2. Amendment No. 176 to NPF-77
- 3. Amendment No. 182 to NPF-37
- 4. Amendment No. 182 to NPF-66
- 5. Safety Evaluation
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 DOCKET NO. STN 50-456 BRAIDWOOD STATION, UNIT 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 176 License No" NPF-72
- 1. The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Exelon Generation Company, LLC (the licensee) dated July 23,2012. as supplemented by letter dated May 1, 2013, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act) and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. 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; D. 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 E. 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.
- 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. NPF-72 is hereby amended to read as follows:
(2) Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 176 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into the license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3. This license amendment is effective as of the date of its issuance and shall be implemented within 45 days of the date of issuance.
FOR THE NUCLEAR REGULA TORY COMMISSION fJt (Yh/1_ ~-
Travis L. Tate, Chief Plant Licensing 111-2 and Planning and Analysis Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Technical Specifications and Facility Operating License Date of Issuance: July 21, 2014
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 EXELON GENERATION COMPANY, LLC DOCKET NO. STN 50-457 BRAIDWOOD STATION, UNIT 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 176 License No. NPF-77
- 1. The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Exelon Generation Company, LLC (the licensee) dated July 23, 2012, as supplemented by letter dated May 1, 2013, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act) and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. 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; D. 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 E. 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.
- 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. NPF-77 is hereby amended to read as follows:
(2) Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 176 and the Environmental Protection Plan contained in Appendix 8, both of which are attached to License No. NPF-72, dated July 2, 1987, are hereby incorporated into this license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3. This license amendment is effective as of the date if its issuance and shall be implemented within 45 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION
/!j_ ~~ to~
Travis L. Tate, Chief Plant Licensing 111-2 and Planning and Analysis Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Technical Specifications and Facility Operating License Date of Issuance: July 21, 2014
ATTACHMENT TO LICENSE AMENDMENT NOS. 176 AND 176 FACILITY OPERATING LICENSE NOS. NPF-72 AND NPF-77 DOCKET NOS. STN 50-456 AND STN 50-457 Replace the following pages of the Facility Operating Licenses and Appendix "A" Technical Specifications with the attached pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.
Remove License NPF-72 License NPF-72 Page 3 Page 3 License NPF-77 License NPF-77 Page 3 Page 3 TSs TSs 3.5.3-1 3.5.3-1
(3) Exelon Generation Company, 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; (4) Exelon Generation Company, 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; and (5) Exelon Generation Company, 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.
C. The 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:
(1) Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent rated power) in accordance with the conditions specified herein and other items identified in Attachment 1 to this license. The items identified in Attachment 1 to this license shall be completed as specified. Attachment 1 is hereby incorporated into this license.
(2) Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No.17 6 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into the license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3) Emergency Planning In the event that the NRC finds that the lack of progress in completion of the procedures in the Federal Emergency Management Agency's final rule, 44 CFR Part 350, is an indication that a major substantive problem exists in achieving or maintaining an adequate state of emergency preparedness, the provision of 10 CFR Section 50.54(s)(2) will apply.
Amendment No . .176
material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amou*nts as required; (4) Exelon Generation Company, LLC 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; and (5) Exelon Generation Company, LLC 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.
C. The 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:
(1) Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent rated power) in accordance with the conditions specified herein and other items identified in Attachment 1 to this license. The items identified in Attachment 1 to this license shall be completed as specified. Attachment 1 is hereby incorporated into this license.
(2) Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No.176 and the Environmental Protection Plan contained in Appendix B, both of which are attached to License No. NPF-72, dated July 2, 1987, are hereby incorporated into this license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3) Emergency Planning In the event that the NRC finds that the lack of progress in completion of the procedures in the Federal Emergency Management Agency's final rule, 44 CFR Part 350, is an indication that a major substantive problem exists in achieving or maintaining an adequate state of emergency preparedness, the provision of 10 CFR Section 50.54(s)(2) will apply.
Amendment No. 1 7 6
ECCS-Shutdown 3.5.3 3.5 EMERGENCY CORE COOLING SYSTEMS CECCS) 3.5.3 ECCS-Shutdown LCO 3.5.3 One ECCS train shall be OPERABLE.
APPLICABILITY: MODE 4.
ACTIONS
NOTE---------------------------------
LCO 3.0.4.b is not applicable to ECCS high head subsystem.
CONDITION REQUIRED ACTION COMPLETION TIME A. Required ECCS RHR A.1 Initiate action to Immediately subsystem inoperable. restore required ECCS RHR subsystem to OPERABLE status.
B. Required ECCS B.1 Restore required ECCS 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> centrifugal charging centrifugal charging subsystem inoperable. subsystem to OPERABLE status.
- c. Required Action and C.1 Be in MODE 5. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> associated Completion Time of Condition B not met.
BRAIDWOOD - UNITS 1 &2 3.5.3- 1 Amendment . 1 7 6
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 EXELON GENERATION COMPANY, LLC DOCKET NO. STN 50-454 BYRON STATION, UNIT NO. 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 182 License No. NPF-37
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Exelon Generation Company, LLC (the licensee) dated July 23, 2012, as supplemented by letter dated May 1, 2013, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act) and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. 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; D. 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 E. 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.
- 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. NPF-37 is hereby amended to read as follows:
(2) Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 182 and the Environmental Protection Plan contained in Appendix 8, both of which are attached hereto, are hereby incorporated into this license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3. This license amendment is effective as of the date of its issuance and shall be implemented within 45 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION
&~ &/
Travis L. Tate, Chief Plant Licensing 111-2 and Planning and Analysis Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Technical Specifications and Facility Operating License Date of Issuance: July 21, 2014
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 EXELON GENERATION COMPANY, LLC DOCKET NO. STN 50-455 BYRON STATION, UNIT NO. 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 182 License No. NPF-66
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A The application for amendment by Exelon Generation Company, LLC (the licensee) dated July 23, 2012, as supplemented by letter dated May 1, 2013, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act) and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. 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; D. 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 E. 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.
- 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility Operating License No. NPF-66 is hereby amended to read as follows:
(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A (NUREG-1113), as revised through Amendment No. 182 and the Environmental Protection Plan contained in Appendix 8, both of which were attached to License No. NPF-37, dated February 14, 1985, are hereby incorporated into this license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3. This license amendment is effective as of the date of its issuance and shall be implemented within 45 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION
/Jh ~~ b Travis L. Tate, Chief Plant Licensing 111-2 and Planning and Analysis Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Technical Specifications and Facility Operating License Date of Issuance: July 21, 2014
ATTACHMENT TO LICENSE AMENDMENT NOS. 182 AND 182 FACILITY OPERATING LICENSE NOS. NPF-37 AND NPF-66 DOCKET NOS. STN 50-454 AND STN 50-455 Replace the following pages of the Facility Operating License and Appendix A Technical Specifications with the attached pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.
Remove License NPF-37 License NPF-37 Page 3 Page 3 License NPF-66 License NPF-66 Page 3 Page 3 TSs TSs 3.5.3-1 3.5.3-1
(4) Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required any byproduct, source and special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and (5) 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.
C. 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:
(1) Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent power) in accordance with the conditions specified herein.
(2) Technical Specifications The Technical SpE:lcifications contained in Appendix A as revised through Amendment No. 18 2 and the Environmental Protection Plan contained in Appendix B, both of wh;cn are attached hereto, are hereby incorporated into this license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3) Deleted.
(4) Deleted.
(5) Deleted.
(6) The license shall implement and maintain in effect all provisions of the approved fire protection program as described in the licensee's Fire Protection Report, and as approved in the SER dated February 1987 through Supplement No. 8, subject to the following provision:
The licensee may make changes to the approved fire protection program without prior approval of the Commission only if those changes would not adversely affect the ability to achieve and maintain safe shutdown in the event of a fire.
Amendment No. 18 2
(3) 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; (4) 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; and (5) 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.
C. The 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:
(1) Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent rated power) in accordance with the conditions specified herein.
(2) Technical Specifications The Technical Specifications contained in Appendix A (NUREG-1113), as revised through Amendment No.182'and the Environmental Protection Plan contained in Appendix B, both of which were attached to License No. NPF-37, dated February 14, 1985, are hereby incorporated into this license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3) Deleted.
(4) Deleted.
(5) Deleted.
Amendment No. 18 2
ECCS-Shutdown 3.5.3 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3.5.3 ECCS-Shutdown LCO 3.5.3 One ECCS train shall be OPERABLE.
APPLICABILITY: MODE 4.
ACTIONS
NOTE---------------------------------
LCO 3.0.4.b is not applicable to ECCS high head subsystem.
CONDITION REQUIRED ACTION COMPLETION TIME A. Required ECCS RHR A.1 Initiate action to Immediately subsystem inoperable. restore required ECCS RHR subsystem to OPERABLE status.
B. Required ECCS B.1 Restore required ECCS 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> centrifugal charging centrifugal charging subsystem inoperable. subsystem to OPERABLE status.
C. Required Action and C.1 Be in MODE 5. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> associated Completion Time of Condition B not met.
BYRON - UNITS 1 &2 3.5.3 - 1 Amendment 182
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 176 TO FACILITY OPERATING LICENSE NO. NPF-72, AMENDMENT NO. 176 TO FACILITY OPERATING LICENSE NO. NPF-77, AMENDMENT NO. 182 TO FACILITY OPERATING LICENSE NO. NPF-37, AND AMENDMENT NO. 182 TO FACILITY OPERATING LICENSE NO. NPF-66 EXELON GENERATION COMPANY, LLC BRAIDWOOD STATION, UNITS 1 AND 2 BYRON STATION, UNIT NOS. 1 AND 2 DOCKET NOS. STN 50-456, STN 50-457, STN 50-454, AND STN 50-455
1.0 INTRODUCTION
By application to the U.S. Nuclear Regulatory Commission (NRC, the Commission) dated July 23, 2012 (Reference 1), as supplemented by letter dated May 1, 2013 (Reference 2),
Exelon Generation Company, LLC (EGC, the licensee) requested changes to the technical
- specifications (TSs) for the Braidwood Station, Units 1 and 2 (Braidwood), and Byron Station Unit Nos. 1 and 2 (Byron). The proposed changes would delete the limiting condition for operation (LCO) Note associated with TSs Section 3.5.3, "ECCS [emergency core cooling system]- Shutdown."
The NRC staff determined that the supplement dated May 1, 2013, provided clarifying information that did not change the scope of the request and did not change the NRC staff's proposed finding of no significant hazards determination published in the Federal Register (77 FR 67682; November 13, 2012).
2.0 REGULATORY EVALUATION
In Section 4.0 of its July 23, 2012, submittal, the licensee identified applicable regulatory requirements. The regulatory requirements on which the NRC staff based its acceptance are summarized below.
Enclosure 5
Title 10 of the Code of Federal Regulations (1 0 CFR) Part 50, Appendix A, General Design Criteria (GDC) 34, requires a residual heat removal (RHR) system designed to maintain specified acceptable fuel design limits and to meet design conditions that are not exceeded if a single-failure occurs simultaneous with failure of specified electrical power systems.
GDC 35, 36, and 37 require an ECCS design that meets performance, inspection, and testing requirements.
Section 50.36(c)(2) of 10 CFR defines the LCO as the lowest functional capability or performance levels of equipment required for safe operation of the facility. 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 TSs until the condition can be met. Further, 10 CFR 50.36( c)(2)(ii) requires that a TS LCO must be established for a structure, system, or component that is part of the primary success path and functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier.
The regulations in 10 CFR 50.46 provide specified ECCS performance criteria.
3.0 TECHNICAL EVALUATION
The primary function of the ECCS is to remove heat from the reactor core during accident conditions. ECCS components include the centrifugal charging, safety injection and RHR pumps, accumulators, heat exchangers, and the refueling water storage tank (RWST), along with the associated piping, valves, instrumentation, and other related equipment. During the initial part of an event requiring ECCS actuation, a flow path is required to provide RWST water to the reactor coolant system (RCS) via the ECCS pumps and the supply headers to the four cold-leg injection nozzles. In the long term, water may be supplied from the containment sump and delivered to the RCS hot- and cold-legs.
Following a loss-of-coolant accident (LOCA), the RHR system performs two functions as the low head portion of the ECCS:
- Provides a long-term recirculation capability for core cooling.
During MODES 1, 2, and 3, both ECCS trains are required to be operable and the RHR system is aligned to perform the ECCS low-head injection function. During Mode 4, the TS 3.5.3 LCO requires that one ECCS train be operable. The RHR pumps are also used for core decay heat removal (DHR) during normal RHR when in MODES 4 and 5.
Currently, the Braidwood and Byron Stations TS 3.5.3 LCO Note states that RHR may be considered operable during alignment and operation for DHR if capable of being manually realigned to the ECCS mode of operation. In its July 23, 2012, application, the licensee states that the Note is nonconservative because it allows the operation of an RHR train as a subsystem of ECCS, in the shutdown cooling mode during MODE 4. Because the potential for steam binding of the RHR pump suction piping occurs when the RCS hot-leg temperature is
greater than 260 degrees Fahrenheit (°F) and the RHR train is realigned to the RWST, one RHR train must remain aligned for the ECCS mode of operation to satisfy LCO TS 3.5.3 when RCS hot-leg temperature is greater than 260 °F.
The licensee stated that Westinghouse issued Nuclear Safety Advisory Letter (NSAL)93-004 (Reference 3), that identified a potential concern associated with steam flashing of hot water in the RHR system suction piping when the RHR system is transferred from the shutdown cooling mode to the ECCS mode with the lower pressure RWST aligned as the RHR system water source. EGC stated that its evaluation determined that the RWST elevation head was sufficient to prevent flashing of water when the RHR suction piping temperature was less than 260 °F.
The NSAL-93-004 evaluation resulted in guidance being incorporated into the Braidwood and Byron Stations procedures to prevent flashing during realignment to the RWST. Further, a change to Braidwood and Byron Stations' Bases forTS 3.5.3 LCO was implemented to ensure that one RHR train remained aligned for ECCS mode of operation whenever RCS hot-leg temperature was greater than 260 °F.
The licensee further stated that in 2009, Westinghouse issued NSAL-09-8 (Reference 4), to clarify previous guidance provided in NSAL-93-004 to ensure that affected facilities take into consideration the significantly reduced elevation head present when the RHR system supply is transferred from the RWST to the ECCS recirculation sump. EGC's evaluation of NSAL-09-8 confirmed that the 260 oF limit applied to the RHR system for alignment for ECCS injection was sufficient to prevent flashing/voiding in RHR system piping when aligned to the RWST, but could result in flashing of liquids in the hot-leg suction lines when the RHR system is transferred to the ECCS recirculation sump. This potential exists due to the elevation differences between the RHR lines at the containment penetrations and the expected containment sump level combined with the postulated containment pressure at the established 260 oF limit. EGC's evaluation concluded that the RCS temperature must be reduced to less than or equal to 200 oF in order to eliminate the potential for flashing of hot water within the isolated RHR system hot-leg suction piping during transfer to the ECCS recirculation sump. Therefore, this condition affects the manner in which the RHR system will be required to be operated in MODE 4 at RCS temperatures greater than 200 oF. The licensee implemented corrective actions at Braidwood and Byron Stations to address the issue based on EGC's evaluation, which included implementation of a standing licensee order under 10 CFR 50.59 to provide guidance and establish controls for the RHR system alignment as an interim action until procedure revisions were completed. The standing order directed that any RHR train operating in the shutdown cooling mode greater than 200 oF was not to be considered immediately available for alignment to the ECCS mode of operation. Revisions of associated operating and emergency procedures to reflect the more restrictive 200 oF temperature limit for alignment of an RHR train for ECCS injection following termination of shutdown cooling were completed and implemented as permanent corrective actions.
Subsequently, Braidwood and Byron Stations provided licensee event reports (LERs) 2010-007-00 and 2011-001-00 (References 5 and 6), that identified occurrences where both RHR trains were placed into shutdown cooling operation prior to reaching Mode 5 where conditions existed that could have prevented fulfillment of a safety function.
In Reference 1, the licensee evaluated whether or not a significant hazards consideration is involved with the proposed amendment by addressing the following three standards set forth in 10 CFR 50.92(c), "Issuance of amendment":
- 1. Does the change involve a significant increase in the probability or consequences of an accident previously evaluated?
- 2. Does the change create the possibility of a new or different kind of accident from any accident previously evaluated?
- 3. Does the change involve a significant reduction in margin of safety?
The NRC staff review of EGC response to Standards 2 and 3 determined that the EGC response was adequate but that EGC should reconsider the Standard 1 response because it did not specifically address the impact of operator errors. This was addressed in an NRC request for additional information (RAI), (Reference 7), which stated "Provide an explanation of accidents that have occurred that were initiated by operator error such as inappropriate valve manipulations." In its May 1, 2013, response to the RAI, EGC revised its addressing of Standard 1 to be as follows:
The proposed changes to delete the TS 3.5.3 LCO Note will ensure that one train of RHR remains aligned for ECCS mode of operation as required to mitigate an accident described in the Updated Final Safety Analysis Report (UFSAR). The proposed changes do not affect the ECCS and RHR system design, operating procedures, and administrative controls that have the function of preventing or mitigating any of the postulated design basis accidents as described in the UFSAR. Furthermore, the interfaces between the RHR system and other plant systems' operating functions, or the reliability of the RHR system are not impacted by the proposed changes. The proposed changes do not change or impact the initiators and assumptions of the analyzed accidents. Therefore, the ECCS and RHR systems will be capable of performing their accident mitigation functions, and the proposed deletion of the TS 3.5.3 LCO Note does not involve a significant increase in the probability of an accident.
The proposed changes will ensure that one train of RHR be available for ECCS mode of operation during MODE 4 to ensure that the RHR system, as a subsystem of ECCS, is operable for ensuring sufficient ECCS flow is available to the core for mitigating the consequences of a loss of coolant accident (LOCA).
Thus, the proposed deletion of the TS 3.5.3 LCO Note does not involve a significant increase in the consequences of an accident.
This wording addressed the NRC staff's concern because it clarifies the licensee's response such that it no longer excludes operator error. With this change, the NRC staff concluded that the EGC response to Standard 1 was adequate.
The NRC staff determined that the above information is a clarification that did not change the scope of the licensee's request and did not change the NRC staff's proposed finding of no significant hazards determination published in the Federal Register (77 FR 67682; November 13, 2012).
Deletion of the Note removes the option to assume RHR is operable without considering the potential for steam flashing (temperatures greater than 200 °F) in the RHR system that would render RHR inoperable. As a result, RHR cannot be considered operable under conditions in which steam binding of the RHR pump suction piping could occur. Since TS LCO 3.5.3 establishes the LCO for the RHR system, removal of the Note does not affect compliance with 10 CFR 50.36(c)(2)(ii). Therefore, the NRC staff determined that the deletion of the Note removed the nonconservative TS and is acceptable.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Illinois State official was notified of the proposed issuance of the amendment. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendments change the requirements with respect to installation or use of a facility's 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 (77 FR 67682; November 13, 2012). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 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.
6.0 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) there is reasonable assurance that 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.
7.0 REFERENCES
- 1. "License Amendment Request to Revise Technical Specifications Section 3.5.3, ECCS-Shutdown," Exelon Generation Company, LLC, July 23, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12206A057).
- 2. "Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications Section 3.5.3, 'ECCS- Shutdown' (TAC Nos. ME9134, ME9135, ME9136, and ME9137}," May 1, 2013 (ADAMS Accession No. ML13122A046).
- 3. "RHRS Operation as Part of the ECCS during Plant Startup," NSAL- 93-004, Westinghouse, April 20, 1993 (ADAMS Accession No. ML13354A809).
- 4. "Presence of Vapor in ECCS/RHR," NSAL-09-8, Westinghouse, November 3, 2009 (ADAMS Accession No. ML13354A811 ).
- 5. "Potential Loss of Residual Heat Removal System Safety Function in Mode 4 When Aligned for Shutdown Cooling Due to Potential for Flashing or Voiding of Coolant During a Shutdown Loss of Coolant Accident," LER 2010-007-00, January 18, 2011 (ADAMS Accession No. ML110180428).
- 6. "Potential Loss of Residual Heat Removal System Safety Function in Mode 4 When Aligned for Shutdown Cooling Due to Potential for Flashing or Voiding of Coolant During a Shutdown Loss of Coolant Accident," LER 2011-001-00, March 7, 2011 (ADAMS Accession No. ML110660223).
- 7. "Byron Station, Units 1 And 2, and Braidwood Station, Units 1 And 2- Request For Additional Information Related To License Amendment Request To Revise Technical Specifications (TS) Section 3.5.3, 'ECCS [Emergency Core Cooling System] Shutdown' (TAC Nos. ME9134, ME9135, ME9136, AND ME9137," NRC Request for Additional Information, March 28, 2013 (ADAMS Accession No. ML13086A589).
Principal Contributor: Warren Lyon Date of issuance: July 21, 2014
A copy of the Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.
Sincerely, IRA/
Joel S. Wiebe, Senior Project Manager Plant Licensing 111-2 and Planning and Analysis Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN 50-456, STN 50-457, STN 50-454 and STN 50-455
Enclosures:
- 1. Amendment No. 176 to NPF-72
- 2. Amendment No. 176 to NPF-77
- 3. Amendment No. 182 to NPF-37
- 4. Amendment No. 182 to NPF-66
- 5. Safety Evaluation DISTRIBUTION:
PUBLIC LPL3-2 RIF RidsNrrDirsltsb Resource RidsRgn3MaiiCenter Resource RidsNrrDorllpl3-2 Resource RidsNrrLASRohrer Resource RidsNrrPMByron Resource RidsNrrDoriDpr Resource RidsNrrPMBraidwood Resource RidsAcrsAcnw_MaiiCTR Resource RecordsAmend Resource RidsNrrDssSrxb Resource Accession Number: ML13311B481 *bJy memo OFFICE LPL3-2/PM LPL3-2/LA SRXB/BC* DIRS/ITSB OGC LPL3-2/BC LPL3-2/PM NAME JWiebe SRohrer CJackson REIIiott MYou~w/com TTate (BPurnell for) JWiebe DATE 7/10/14 7/18/14 8/ 5/13 11/18/13 5/13/14 7/21/14 7/21 /14