ML13282A534

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Issuance of Amendment No. 207, Revise Technical Specification 3.4.12, Low Temperature Overpressure Protection (LTOP) System, to Reflect Mass Input Transient Analysis
ML13282A534
Person / Time
Site: Wolf Creek Wolf Creek Nuclear Operating Corporation icon.png
Issue date: 12/06/2013
From: Lyon C
Plant Licensing Branch IV
To: Matthew Sunseri
Wolf Creek
Lyon C
References
TAC MF0309
Download: ML13282A534 (17)


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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001

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December 6, 2013 Mr. Matthew W. Sunseri President and Chief Executive Officer Wolf Creek Nuclear Operating Corporation Post Office Box 411 Burlington, KS 66839

SUBJECT:

WOLF CREEK GENERATING STATION -ISSUANCE OF AMENDMENT RE:

REVISE TECHNICAL SPECIFICATION 3.4.12, "LOW TEMPERATURE OVERPRESSURE PROTECTION (LTOP) SYSTEM" (TAC NO. MF0309)

Dear Mr. Sunseri:

The U.S. Nuclear Regulatory Commission (the Commission) has issued the enclosed Amendment No. 207 to Renewed Facility Operating License No. NPF 42 for the Wolf Creek Generating Station. The amendment consists of a change to the Technical Specifications (TSs) in response to your application dated November 21, 2012, as supplemented by letters dated February 25 and May 28, 2013.

The amendment revises TS 3.4.12, "Low Temperature Overpressure Protection (LTOP)

System," to reflect the mass input transient analysis that assumes an emergency core cooling system centrifugal charging pump and the normal charging pump capable of injecting into the reactor coolant system during the TS 3.4.12 Applicability.

A copy of our related Safety Evaluation is enclosed. The Notice of Issuance will be included in the Commission's next biweekly Federal Register notice.

Sincerely, u=~

Carl F. Lyon, Project Manager Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-482

Enclosures:

1. Amendment No. 207 to NPF-42
2. Safety Evaluation cc w/encls: Distribution via Listserv

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WOLF CREEK NUCLEAR OPERATING CORPORATION WOLF CREEK GENERATING STATION DOCKET NO. 50-482 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 207 License No. NPF-42

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment to the Wolf Creek Generating Station (the facility)

Renewed Facility Operating License No. NPF-42 filed by the Wolf Creek Nuclear Operating Corporation (the Corporation), dated November 21, 2012, as supplemented by letters dated February 25 and May 28, 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, as amended, 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 license 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.

Enclosure 1

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 Renewed Facility Operating License No. NPF-42 is hereby amended to read as follows:

(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 207, and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated in the license. The Corporation shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.

3. The license amendment is effective as of its date of issuance and shall be implemented within 90 days of the date of issuance.

FOR THE NUCLEAR REGULA TORY COMMISSION

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Michael T. Markley, Chief Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to the Renewed Facility Operating License and Technical Specifications Date of Issuance: December 6, 2013

ATTACHMENT TO LICENSE AMENDMENT NO. 207 RENEWED FACILITY OPERATING LICENSE NO. NPF-42 DOCKET NO. 50-482 Replace the following pages of the Renewed Facility Operating License No. NPF-42 and Appendix A Technical Specifications with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.

Renewed Facility Operating License REMOVE INSERT 4 4 Technical Specifications REMOVE INSERT 3.4-26 3.4-26 3.4-27 3.4-27 3.4-29 3.4-29

4 (5) The Operating Corporation, 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 (6) The Operating Corporation, 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 renewed operating license shall be deemed to contain and is subject to the conditions specified in the Commission=s regulations 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 Operating Corporation is authorized to operate the facility at reactor core power levels not in excess of 3565 megawatts thermal (100%

power) in accordance with the conditions specified herein.

(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 207, and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated in the license. The Corporation shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.

(3) Antitrust Conditions Kansas Gas & Electric Company and Kansas City Power & Light Company shall comply with the antitrust conditions delineated in Appendix C to this license.

(4) Environmental Qualification (Section 3.11. SSER #4, Section 3.11, SSER #5)*

Deleted per Amendment No. 141.

  • The parenthetical notation following the title of many license conditions denotes the section of the supporting Safety Evaluation Report and/or its supplements wherein the license condition is discussed.

Renewed License No. NPF-42 Amendment No. 207

LTOP System 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Low Temperature Overpressure Protection (LTOP) System LCO 3.4.12 An LTOP System shall be OPERABLE with a maximum of zero safety injection pumps, one Emergency Core Cooling System (ECCS) centrifugal charging pump, and the normal charging pump capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:

a. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR, or
b. Two residual heat removal (RHR) suction relief valves with setpoints
436.5 psig and~ 463.5 psig, or
c. One PORV with a lift setting within the limits specified in the PTLR and one RHR suction relief valve with a setpoint;::: 436.5 psig and

~ 463.5 psig, or

d. The RCS depressurized and an RCS vent of;::: 2.0 square inches.

NOTES---------------------------------------------------

1. Two ECCS centrifugal charging pumps may be made capable of injecting for~ 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for pump swap operation.
2. Two safety injection pumps and two ECCS centrifugal charging pumps may be made capable of injecting into the RCS: (a) in MODE 3 with any RCS cold leg temperature ~ 368°F and ECCS pumps OPERABLE pursuant to LCO 3.5.2, "ECCS - Operating," and (b) for up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after entering MODE 4 from MODE 3 or until the temperature of one or more RCS cold leg decreases below 325°F, whichever comes first.
3. One or more safety injection pumps may be made capable of injecting into the RCS in MODES 5 and 6 when the RCS water level is below the top of the reactor vessel flange for the purpose of protecting the decay heat removal function.
4. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS pressure for the existing RCS cold leg temperature allowed by the Prr limit curves provided in the PTLR.

Wolf Creek - Unit 1 3.4-26 Amendment No. ~. 207

LTOP System 3.4.12 APPLICABILITY: MODE 3, with any RCS cold leg temperature :5: 368°F, MODE4, MODE 5, MODE 6 when the reactor vessel head is on.

ACTIONS


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LCO 3.0.4b. is not applicable when entering MODE 4 or MODE 3.

CONDITION REQUIRED ACTION COMPLETION TIME A. One or more safety A.1 Initiate action to verify a Immediately injection pumps capable of maximum of zero safety injecting into the RCS. injection pumps are capable of injecting into the RCS.

B. Two ECCS centrifugal 8.1 Initiate action to verify a Immediately charging pumps capable of maximum of one ECCS injecting into the RCS. centrifugal charging pump and the normal charging pump capable of injecting into the RCS.

C. An accumulator not C.1 Isolate affected 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> isolated when the accumulator.

accumulator pressure is greater than or equal to the maximum RCS pressure for existing cold leg temperature allowed in the PTLR.

~ -~-- -- --* - - - - - --

(continued)

Wolf Creek - Unit 1 3.4-27 Amendment No. 123. 155, 207

LTOP System 3.4.12 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.12.1 Verify a maximum of zero safety injection pumps are I 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> capable of injecting into the RCS.

SR 3.4.12.2 Verify a maximum of one ECCS centrifugal charging I 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> pump and the normal charging pump capable of injecting into the RCS.

SR 3.4.12.3 Verify each accumulator is isolated when I 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed by the PIT limit curves provided in the PTLR.

SR 3.4.12.4 Verify RHR suction isolation valves are open for each I 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> required RHR suction relief valve.

SR 3.4.12.5 Verify required RCS vent;:: 2.0 square inches open. I 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for vent pathway(s) not locked, sealed or otherwise secured in the open position AND 31 days for vent valve(s) locked, sealed or otherwise secured in the open position (continued)

Wolf Creek - Unit 1 3.4-29 Amendment No. ~. 207

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"7 ~o" SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 207 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-42 WOLF CREEK NUCLEAR OPERATING CORPORATION WOLF CREEK GENERATING STATION DOCKET NO. 50-482

1.0 INTRODUCTION

By application dated November 21, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12334A406), as supplemented by letters dated February 25 and May 28, 2013 (ADAMS Accession Nos. ML13072A297 and ML13156A338, respectively), Wolf Creek Nuclear Operating Corporation (the licensee) requested a change to the Technical Specifications (TSs) for Wolf Creek Generating Station (WCGS). The supplemental letters dated February 25 and May 28, 2013, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the U.S. Nuclear Regulatory Commission (NRC) staff's original proposed no significant hazards consideration determination as published in the Federal Register on February 5, 2013 (78 FR 8200).

The proposed change would revise TS 3.4.12, "Low Temperature Overpressure Protection (LTOP) System," to reflect the mass input transient analysis that assumes an emergency core cooling system (ECCS) centrifugal charging pump (CCP) and the normal charging pump (NCP) capable of injecting into the reactor coolant system (RCS) during the TS 3.4.12 Applicability.

The change clarifies the TS to reflect the position that the Limiting Condition for Operation (LCO) is met when both safety injection pumps and one CCP are not capable of injecting into the RCS, but the second CCP and NCP are capable of injecting into the RCS.

2.0 REGULATORY EVALUATION

2.1 System Description The LTOP System controls RCS pressure at low temperatures so the integrity of the reactor coolant pressure boundary (RCPB) is not compromised in low-temperature modes of operation.

LCO 3.4.12 provides overpressure protection by specifying a minimum coolant input capability and an adequate pressure relief capability.

Enclosure 2

2.2 Applicable Regulatory Requirements Section 182a of the Atomic Energy Act requires applicants for nuclear power plant operating licenses to include TSs as part of the license. In Section 50.36, "Technical specifications," of Title 10 of the Code of Federal Regulations (1 0 CFR), the NRC established its regulatory requirements related to the content of TSs. Pursuant to 10 CFR 50.36, TSs are required to include items in the following five specific categories related to station operation: (1) safety limits, limiting safety system settings, and limiting control settings, (2) LCOs, (3) surveillance requirements (SRs), (4) design features, and (5) administrative controls. The rule does not specify the particular requirements to be included in a plant's TS. The regulations in 10 CFR 50.36(c)(2)(i), state, in part, that the "[l]imiting conditions for operation are the lowest functional capability or performance levels of equipment required for safe operation of the facility." More specifically, 10 CFR 50.36 (c)(2)(ii) states "A technical specification limiting condition for operation of a nuclear reactor must be established for each item meeting one or more of the following criteria: [... ]Criterion 2. A process variable, design feature,, or operating restriction that is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier."

The LTOP system controls RCS pressure at low temperatures so that the integrity of the RCPB is not compromised by violating the pressure and temperature limits required by 10 CFR Part 50, Appendix G, "Fracture Toughness Requirements." The LCO ensures that only a limited inventory of mass input sources are available for injection into the RCS during low-temperature operation, consistent with Criterion 2 of 10 CFR 50.36(c)(2)(ii).

3.0 TECHNICAL EVALUATION

3.1 Proposed TS Changes Current TS LCO 3.4.12 states, in part:

An LTOP System shall be OPERABLE with a maximum of zero safety injection pumps and one centrifugal charging pump capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:

Revised TS LCO 3.4.12 would state, in part:

An LTOP System shall be OPERABLE with a maximum of zero safety injection pumps, one Emergency Core Cooling System (ECCS) centrifugal charging pump, and the normal charging pump capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:

Current Notes 1 and 2 for the LCO state:

1. Two centrifugal charging pumps may be made capable of injecting for s;1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for pump swap operation.
2. Two safety injection pumps and two centrifugal charging pumps may be made capable of injecting into the RCS: (a) in MODE 3 with any RCS cold leg temperature ~ 368°F and ECCS pumps OPERABLE pursuant to LCO 3.5.2, "ECCS- Operating," and (b) for up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after entering MODE 4 from MODE 3 or until the temperature of one or more RCS cold leg decreases below 325°F, whichever comes first.

Revised Notes 1 and 2 for the LCO would state:

1. Two ECCS centrifugal charging pumps may be made capable of injecting for ~1 hour for pump swap operation.
2. Two safety injection pumps and two ECCS centrifugal charging pumps may be made capable of injecting into the RCS: (a) in MODE 3 with any RCS cold leg temperature ~ 368°F and ECCS pumps OPERABLE pursuant to LCO 3.5.2, "ECCS- Operating," and (b) for up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after entering MODE 4 from MODE 3 or until the temperature of one or more RCS cold leg decreases below 325°F, whichever comes first There are specific actions in TS LCO 3.4.12 that are related to these pumps, Actions A and B.

Action A applies to the given condition, one or more safety injection pumps capable of injecting into the RCS, and requires action to verify a maximum of zero safety injection pumps are capable of injecting into the RCS to be completed immediately. Action B applies to given condition, two CCPs capable of injecting into the RCS, and requires action to verify a maximum of one CCP is capable of injecting into the RCS to be completed immediately.

Notes 1 and 2 of LCO 3.4.12 and Condition B would be revised to specify the CCPs as ECCS CCPs.

Current Condition B states:

Two centrifugal charging pumps capable of injecting into the RCS.

Revised Condition B would state:

Two ECCS centrifugal charging pumps capable of injecting into the RCS.

Current Required Action B.1 states:

Initiate action to verify a maximum of one centrifugal charging pump is capable of injecting into the RCS.

Revised Required Action B.1 would state:

Initiate action to verify a maximum of one ECCS centrifugal charging pump and the normal charging pump capable of injecting into the RCS.

Current SR 3.4.12.2 states:

Verify a maximum of one centrifugal charging pump is capable of injecting into the RCS.

Revised SR 3.4.12.2 would state:

Verify a maximum of one ECCS centrifugal charging pump and the normal charging pump capable of injecting into the RCS.

3.2 Summary of Technical Information Provided by the Licensee In its letter dated November 21, 2012, the licensee stated, in part, that The mass input transient analysis assumes simultaneous injection of both a CCP and the NCP into the water-solid RCS while the Residual Heat Removal (RHR)

System and the letdown line are isolated. This assumption is consistent with the TS LCO, which requires all safety injection pumps and one of the two ECCS CCPs to be made incapable of injecting into the RCS and therefore, allows a CCP to be OPERABLE and the NCP to be functional under these modes of operation ...

The mass input analysis addresses the proposed changes to Note 1 of the LCO 3.4.12 for time allowed for pump swap operation. When maintenance activities are being performed during a refueling outage, trains related to safety equipment are put into or taken out of service.

Performing ECCS CCP swap operations for maintenance activities requires both CCPs to be able to inject for a limited time period. The license stated that the changes to Note 1 for LCO 3.4.12 are acceptable based on adherence to LCO 3.5.3 and Technical Requirement (TR) 3.1.1 0. LCO 3.5.3, "EGGS-Shutdown," requires that the inoperable/nonfunctional CCP must first be restored to OPERABLE status in order for the LCO to be met. TR 3.1.1 0 requires one boration injection subsystem (one ECCS CCP) to be FUNCTIONAL in MODES 4, 5, and 6 in order to be met.

In its letter dated February 25, 2013, the licensee discussed the mass input transient analysis.

The major assumptions used in this analysis are consistent with the NRC-approved methodology outlined in WCAP-14040-A, Revision 4, "Methodology Used to Develop Cold Overpressure Mitigating System Setpoints and RCS Heatup and Cooldown Limit Curves,"

May 2004 (ADAMS Accession No. ML050120209). The following assumptions were listed in the licensee's letter:

1. The design basis for the LTOP system assumes that the Residual Heat Removal (RHR) System is isolated from the RCS, and thus the relief capability of the RHR System relief valves is not available.
2. An initial RCS temperature of 60°F is assumed for the mass input transient, as the LTOP/Power Operated Relief Valve (PORV) setpoints

are selected so that the Appendix G limit will not be exceeded down to the minimum reactor vessel bolt-up temperature of 60°F.

3. The mass injection rate assumed in the design basis mass input transient is based on 100 percent flow capacity of the NCP and one ECCS CCP.

The maximum combined pump flow has been assumed in order to envelop the maximum flow possible by the operational configuration that uses the NCP for charging with one CCP remaining OPERABLE, or the use of one CCP for charging with the NCP remaining OPERABLE, during shutdown modes. The injection flow rates over a range of RCS pressures are provided in Table 1.

4. Based on the single failure criteria, only one pressurizer PORV is assumed to be available to mitigate the transients. The following valve characteristics were assumed:

Ramp {linear) opening characteristics Opening time = 2 seconds, including a 0.9 second delay Closing time = 2 seconds, including a 0.9 second delay Flow coefficient, Cv =50 gpm/.ji)Si

5. The RCS is assumed to be enclosed by a non-yielding, inelastic boundary. The pressurizer is assumed to be in a water solid condition and at the same temperature as the reactor coolant. This maximizes the pressure overshoots during the design basis transients.

The NRC-approved LOFTRAN code, WCAP-7907-P-A, "LOFTRAN Code Description" (ADAMS Legacy Library Accession No. 880811 0429), was used in order to calculate the pressure overshoot and undershoot beyond the PORV open and close setpoints as a result of time delays in signal processing and value stroke following a design basis mass input transient. The key parameters for this analysis include the design basis mass input rates, the plant RCS volumes, pressurizer PORV opening and closing stroke times, PORV characteristics, and instrument delay times are utilized for the development of the mass input transient database.

The license also provided the results and peak pressure acceptance criteria of the mass input analysis in Tables 2 and 3 of its February 25, 2013, letter. When a PORV is actuated to mitigate an increasing pressure transient, the release of coolant will cause the pressure increase to slow and eventually reverse. The system pressure will thus decrease with the coolant relief until the rest pressure is reached. This will give a signal to the valve to close, noting that the pressure will continue to decrease below the reset pressure as the valve re-closes. The results showed that the peak pressures associated with the mass input analyses remained below the Appendix G limits.

In its letter dated February 25, 2013, the licensee referenced the Technical Specification Task Force {TSTF) traveler TSTF-285-A, Revision 1, "Charging Pump Swap LTOP Allowance," that relocated the Note from Required Action B.1 to the LCO. The NRC-approved TSTF-285 (ADAMS Accession No. ML090750111) justifies the allowance for "N+ 1" pumps capable of

injection by showing the mass input transient analysis takes into account other functions requiring an OPERABLE ECCS CCP, so that 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to perform the pump swap operation is reasonable, given the small chance of an event occurring during the brief period required for the swap and accounting for the administrative controls and surveillance requirements associated with the swap.

In its letter dated May 28, 2013, the licensee also provided some additional safety considerations for the exception for Note 1 stated in its letter dated February 25, 2013. The licensee stated that in Procedure STS CR-002, "Shift Log for MODES 4, 5, and 6," an operator verifies that one of the ECCS CCPs is incapable of injection into the RCS once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

The procedure also requires the operators to log the status change of the CCPS following a pump swap. This allows for positive control of the CCPs and ensures only one CCP can inject at any time, aside from pump swap operations.

The licensee stated in its letter dated May 28, 2013, that it referred to the Updated Safety Analysis Report (USAR) Section 5.2.2.1 0.4.1, which discusses the plant procedures to maximize the use of a pressurizer cushion (steam bubble) when there is low pressure, low temperature operation. This cushion allows a dampened plant response to transients that generate inputs, thus providing easier pressure control with slower response rates. Licensee Procedure GEN 00-006 includes the steps for filling the pressurizer for water-solid operation that is normally performed in a specific RCS temperature range. This is done with at least one RHR train in-service, which ensures at least one RHR suction relief is also available for RCS pressure relief. Operating crews are typically trained in performing the shutdown and collapse or form the pressurizer bubble with Just-In-Time training. This is done in real time to enable practicing the evolutions on the simulator prior to performing them in the plant.

3.3 NRC Staff Evaluation The NRC staff evaluated the licensee submittal as described in the following paragraph. The staff reviewed the license request by evaluating the submitted original and supplemental information and verifying that the proposed LCO is consistent with the applicable safety analysis. The staff also verified that the revised Notes, which provide limited exceptions to the LCO, are augmented by adequate station procedures and additional safety considerations to ensure that the exceptions will continue provide adequate protection of the public health and safety.

The NRC staff reviewed the mass input transient analysis provided in the licensee's letter dated February 25, 2013. The NRC staff reviewed this mass input transient analysis and requested additional information from the licensee on the mass input transient analysis to confirm its compliance with 10 CFR 50.36 and Appendix G. This analysis forms the basis for the proposed LCO changes, since it reflects the assumption that the NCP and one ECCS CCP are in operation. The analysis was performed in accordance with NRC-approved methods outlined in WCAP-14040-A, Revision 4, "Methodology Used to Develop Cold Overpressure Mitigating System Setpoints and RCS Heatup and Cooldown Limit Curves" (ADAMS Accession No. ML050120209). The analytic assumptions reflect the RCS in a condition with limited relief capabilities and heightened sensitivity to the mass addition, since the RCS is water-solid. As the plant usually maintains a steam bubble in the pressurizer, the NRC staff determined that this

assumption was conservative. The results of the analysis show that the maximum allowable PORV setpoint pressure as a function of RCS temperature ensures that the RCS pressure does not exceed the Appendix G limits. Based on the licensee's use of the NRC-approved methods with conservative assumptions, and on the acceptable results, the NRC staff determined that the proposed LCO revision was acceptable with respect to the mass input transient analysis.

The LCO, as proposed, would allow, for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, two ECCS CCPs to be in an operable configuration. The mass input analysis does not address this condition. The NRC staff reviewed TSTF-285-A, Insert 1, which states the following:

The LCO is modified by two Notes. Note 1 allows [two charging pumps] to be made capable of injecting for s; 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> during pump swap operations. One hour provides sufficient time to safely complete the actual transfer and to complete administrative controls and surveillance requirements associated with the swap.

The intent is to minimize the actual time that more than [one] charging pump is physically capable of injection.

The NRC staff confirmed, based on its review of TSTF-285-A, Insert 1 that the licensee is consistent with the TSTF, in that the licensee's proposed LCO Note will similarly minimize the actual time that more than one or two charging pumps at a time will be physically capable of injection. Therefore, the NRC staff determined that it is acceptable to have more than one pump capable of injection for pump swap conditions.

Finally, the licensee stated that it maintains a procedure to ensure that pump swap operations are controlled processes. The time window of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of exposure listed in LCO 3.4.12 is minimal. There are procedural requirements in place for pump swap operations that minimize operator error. For this 1-hour time window, there are at least two pressure relief devices (typically the PORVs) for overpressure protection. Therefore, the NRC staff agrees that the 1-hour window allowed in Note 1 gives adequate time for safe completion of the pump swap.

The NRC staff also determined that the procedural controls and additional, available safety features provide assurance that the initiation of a mass input transient while two ECCS CCPs are capable of injecting into the RCS would be very unlikely, and its effects could be acceptably mitigated. Based on these considerations, the NRC staff concludes that the proposed revisions to TS LCO 3.4.12 are acceptable.

The staff determined that the LCO as proposed will specify the lowest functional capability or performance equipment for safe operation of the facility as required by 10 CFR 50.36(c)(2)(i).

The staff made this determination because the LCO aligns with the safety analysis provided by the licensee with respect to the assumed mass input sources in the analysis.

The LCO, as proposed, will restrict the available mass input sources to be consistent with those assumed in the safety analysis, which is consistent with 10 CFR 50.36(c)(2)(ii)(B) in that the LCO will restrict operation to the initial condition assumed in the mass input transient analysis, as described in the preceding paragraphs. This restriction, in turn, assures that the reactor coolant system will not exceed the pressure/temperature limits required by 10 CFR Part 50, Appendix G. Based on these considerations, the NRC staff determined that the proposed LCO revisions are acceptable.

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Kansas State official was notified of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves 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 amendment involves no significant hazards consideration, and there has been no public comment on such finding published in the Federal Register on February 5, 2013 (78 FR 8200). Accordingly, the amendment meets 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 amendment.

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 amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor: M. Hardgrove, SRXB Date: December 6, 2013

ML13282A534 *via memo dated October 4. 2013 OFFICE NRR/DORL/LPL4-1/PM NRR/DORL/LPL4-1/LA NRR/DSS/STSB/BC NRR/DSS/SRXB/BC*

NAME Flyon JBurkhardt REIIiott CJackson DATE 11/13/13 11/7113 11/14/13 10/4/13 OFFICE NAME OGC DRoth NRRIDORULPL4-1/BC NRRIDORULPL4-1/PM MMarkley Flyon I

DATE 12/3/13 12/6/13 12/6/13