Text

Issuance of Amendment Revising Technical Specification Requirements for Ultrasonic Flow Meter Outage Time (CAC No. MF9080; EPID L-2017-LLA-0167)
	ML17270A112
Person / Time
Site:	Davis Besse
Issue date:	10/19/2017
From:	Blake Purnell; Plant Licensing Branch III
To:	Bezilla M; FirstEnergy Nuclear Operating Co
	Purnell B
References
	CAC MF9080, EPID L-2017-LLA-0167
	Download: ML17270A112 (18)
	v • d • e

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 October 19, 2017 Mr. Mark B. Bezilla Site Vice President FirstEnergy Nuclear Operating Company Mail Stop A-DB-3080 5501 North State Route 2 Oak Harbor, OH 43449-9760

SUBJECT:

DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 - ISSUANCE OF AMENDMENT REVISING TECHNICAL SPECIFICATION REQUIREMENTS FOR ULTRASONIC FLOW METER OUTAGE TIME (CAC NO. MF9080, EPID L-2017-LLA-0167)

Dear Mr. Bezilla:

The U.S. Nuclear Regulatory Commission has issued the enclosed Amendment No. 296 to Renewed Facility Operating License No. NPF-3 for the Davis-Besse Nuclear Power Station, Unit No. 1. The amendment is in response to your application dated January 11, 2017 (Agencywide Documents Access and Management System Accession No. ML17011A271).

The amendment revises Technical Specification 3.3.1, "Reactor Protection System (RPS)

Instrumentation," by modifying the format and by providing an alternative set of required actions, with longer completion times, to be used when the ultrasonic flow meter is out of service.

A copy of the NRC staff's Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.

Docket No. 50-346

Enclosures:

1. Amendment No. 296 to NPF-3

2. Safety Evaluation cc w/encls: Distribution via Listserv Blake Purnell, Project Manager Plant Licensing Branch Ill Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 FIRSTENERGY NUCLEAR OPERATING COMPANY AND FIRSTENERGY NUCLEAR GENERATION. LLC DAVIS-BESSE NUCLEAR POWER STATION. UNIT NO. 1 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE DOCKET NO. 50-346 Amendment No. 296 Renewed License No. NPF-3

1.

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

A.

The application for amendment filed by FirstEnergy Nuclear Operating Company (FENOC, the licensee) dated January 11, 2017, 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 Renewed Facility Operating License No. NPF-3 is hereby amended to read as follows:

(2)

Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 296, are hereby incorporated in the renewed license. FENOC shall operate the facility in accordance with the Technical Specifications.

3.

This license amendment is effective as of its date of issuance and shall be implemented within 60 days of the date of issuance.

Attachment:

Changes to the Technical Specifications and Renewed Facility Operating License Date of Issuance: October 19, 201 7 FOR THE NUCLEAR REGULATORY COMMISSION DQ dnaiief cV ---

Plant Licensing Branch Ill Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

ATTACHMENT TO LICENSE AMENDMENT NO. 296 RENEWED FACILITY OPERATING LICENSE NO. NPF-3 DOCKET NO. 50-346 Replace the following pages of the Renewed Facility Operating License and 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 Renewed License NPF-3 L-5 TSs 3.3.1-2 3.3.1-3 3.3.1-4 3.3.1-5 Renewed License NPF-3 L-5 TSs 3.3.1-2 3.3.1-3 3.3.1-4 3.3.1-5

2.C.

This renewed license shall be deemed to contain and is subject to the conditions specified in the following Commission regulations in 10 CFR Chapter I: Part 20, Section 30.34 of Part 30, Section 40.41 of Part 40, Sections 50.54 and 50.59 of Part 50, and Section 70.32 of Part 70; 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 FENOC is authorized to operate the facility at steady state reactor core power levels not in excess of 2817 megawatts (thermal). Prior to attaining the power level, Toledo Edison Company shall comply with the conditions identified in Paragraph (3) (o) below and complete the preoperational tests, startup tests and other items identified in to this license in the sequence specified. Attachment 2 is an integral part of this renewed license.

(2)

Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 296, are hereby incorporated in the renewed license.

FENOC shall operate the facility in accordance with the Technical Specifications.

(3)

Additional Conditions The matters specified in the following conditions shall be completed to the satisfaction of the Commission within the stated time periods following the issuance of the renewed license or within the operational restrictions indicated. The removal of these conditions shall be made by an amendment to the renewed license supported by a favorable evaluation by the Commission:

(a)

FENOC shall not operate the reactor in operational Modes 1 and 2 with less than three reactor coolant pumps in operation.

(b)

Deleted per Amendment 6 (c)

Deleted per Amendment 5 L-5 Renewed License No. NPF-3 Amendment No. 296

ACTIONS (continued)

CONDITION D. As required by Required D.1 Action C.1 and referenced in AND Table 3.3.1-1.

D.2 E. As required by Required E.1 Action C.1 and referenced in Table 3.3.1-1.

F. UFM instrumentation not F.1.1 used to perform SR 3.3.1.2.

AND THERMAL POWER F.1.2

> 50% ATP.

AND OR Four reactor coolant pumps (RCPs)

F.2.1 operating.

Davis-Besse REQUIRED ACTION Be in MODE 3.

NOTE--------------

Only applicable to Functions 1.a, 3, and 6.

Open all CONTROL ROD drive (CRD) trip breakers.

Open all CRD trip breakers.

Initiate action to reduce THERMAL POWER to

.s 98.4% ATP.

AND Reset High Flux - High Setpoint Allowable Value to

.s 103.3% RTP.

Perform SR 3.3.1.2 using calorimetric heat balance based on f eedwater flow venturi readings normalized to the last UFM readings provided THERMAL POWER has been continuously maintained

> 90% RTP since the previous calorimetric heat balance based on UFM readings.

3.3.1-2 RPS Instrumentation 3.3.1 COMPLETION TIME 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 6 hours 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Immediately 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months Immediately Amendment 296

ACTIONS (continued)

CONDITION F. (continued)

F.2.2 F.2.3 G. UFM instrumentation not G.1 used to perform SR 3.3.1.2.

AND THERMAL POWER

> 50% RTP.

AND Three RCPs operating.

SURVEILLANCE REQUIREMENTS REQUIRED ACTION AND Initiate action to reduce THERMAL POWER to

.s 98.4% ATP.

AND Reset High Flux - High Setpoint Allowable Value to

.s 103.3% ATP.

Initiate action to reduce THERMAL POWER to

.s 73.8% ATP.

RPS Instrumentation 3.3.1 COMPLETION TIME 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months since the last calorimetric heat balance based on UFM readings 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months since the last calorimetric heat balance based on UFM readings Immediately

NOTE-----------------------------------------------------------

Refer to Table 3.3.1-1 to determine which SRs apply to each RPS Function.

SURVEILLANCE FREQUENCY SR 3.3.1.1 Perform CHANNEL CHECK.

12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Davis-Besse 3.3.1-3 Amendment 296

SURVEILLANCE REQUIREMENTS (continued)

SR 3.3.1.2 SR 3.3.1.3 SR 3.3.1.4 SURVEILLANCE

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

1.

Adjust power range channel output if the calorimetric heat balance calculation results exceed power range channel output by

> 2% RTP.

2.

Not required to be performed until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months after THERMAL POWER is;:: 15% RTP.

Compare result of calorimetric heat balance calculation to power range channel output.

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

1.

Neutron detectors are excluded from CHANNEL CALIBRATION.

2.

For Function 8, flow rate measurement sensors may be excluded from CHANNEL CALIBRATION.

Perform CHANNEL CALIBRATION.

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

1.

Adjust the power range channel imbalance output if the absolute value of the offset error is

~2.5%.

2.

Not required to be performed until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months after THERMAL POWER is;:: 50% RTP.

Compare results of out of core measured AXIAL POWER IMBALANCE (APlo) to incore measured AXIAL POWER IMBALANCE (APl1) as follows:

(RTP/TP)(APl0 - APl1) =offset error.

RPS Instrumentation 3.3.1 FREQUENCY 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months 23 days on a STAGGERED TEST BASIS 31 days Davis-Besse 3.3.1-4 Amendment 296

SURVEILLANCE REQUIREMENTS (continued)

SR 3.3.1.5 SR 3.3.1.6 SR 3.3.1.7 SR 3.3.1.8 SURVEILLANCE Perform CHANNEL FUNCTIONAL TEST.

Perform CHANNEL CALIBRATION.

N 0 TE------------------------------

For Function 8, flow rate measurement sensors are only required to be calibrated.

Perform CHANNEL CALIBRATION.

NOTE------------------------------

Neutron detectors are excluded from RPS RESPONSE TIME testing.

Verify that RPS RESPONSE TIME is within limits.

RPS Instrumentation 3.3.1 FREQUENCY 46 days on a STAGGERED TEST BASIS 18 months 24 months 24 months on a STAGGERED TEST BASIS Davis-Besse 3.3.1-5 Amendment 296

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 296 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-3 FIRSTENERGY NUCLEAR OPERATING COMPANY FIRSTENERGY NUCLEAR GENERATION, LLC DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 DOCKET NO. 50-346

1.0 INTRODUCTION

By application dated January 11, 2017 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML17011A271 ), FirstEnergy Nuclear Operating Company submitted a license amendment request for Davis-Besse Nuclear Power Station, Unit No. 1 (Davis-Besse). The proposed amendment would revise Technical Specification (TS) 3.3.1, "Reactor Protection System (RPS) Instrumentation," by modifying the format and by providing an alternative set of required actions, with longer completion times, to be used when the ultrasonic flow meter (UFM) is out of service.

2.0 REGULATORY EVALUATION

2.1 Background

At nuclear power plants, the neutron flux instrumentation continuously indicates the reactor core thermal power. This instrumentation must be periodically calibrated to accommodate the effects of fuel burnup, neutron flux pattern changes, and instrumentation setpoint drift. In order to calibrate the instrument, the reactor core thermal power is calculated by performing a heat balance around the nuclear steam supply system (called a calorimetric). The accuracy of this calculation depends primarily upon the accuracy of feedwater flow rate and temperature measurements. As such, an accurate measurement of these parameters is necessary for an accurate calibration of the nuclear instrumentation.

At Davis-Besse, the originally-installed Bailey venturis and resistance temperature detectors (RTDs) continue to measure the feedwater flow rate and temperature. The RTDs are used for water density calculation, which is part of the venturi flow calculation. However, the preferred feedwater flow measurement system used to obtain input to the calorimetric heat balance calculation at Davis-Besse is a Caldon Leading Edge Flow Meter CheckPlus TM ultrasonic, multipath, transit-time flowmeter (referred to as the UFM). The UFM system provides more accurate measurement of feedwater flow than the venturi system, and it also is used to calculate the feedwater temperature. By letter dated June 30, 2008 (ADAMS Accession No. ML081410652), the U.S. Nuclear Regulatory Commission (NRC or Commission) approved a power uprate amendment at Davis-Besse based on the use of the more accurate UFM.

With the power uprate amendment, the Davis-Besse TSs were revised to require use of the UFM during the daily heat balance calculation. The results of the calorimetric are compared to the power range channel instrumentation output and used to normalize the output of the neutron flux power range channels. The power range neutron flux channel output is required to be adjusted if the calorimetric heat balance results exceed power range channel output by more than 2 percent. This ensures that the neutron flux instrumentation is maintained within the analyzed error margins in the Davis-Besse updated final safety analysis report. If the UFM is not available, the TSs require a reduction in thermal power because of the increased uncertainty in feedwater flow measurements.

2.2 Description of Proposed TS Changes Surveillance Requirement (SR) 3.3.1.2 requires the licensee to compare the results of the calorimetric heat balance calculation to power range channel output every 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . TS Limiting Condition for Operation (LCO) 3.3.1 requires, in part, the UFM instrumentation to be used to perform SR 3.3.1.2 when thermal power is greater than 50 percent of rated thermal power (RTP). TS 3.3.1 includes actions the licensee must take if the UFM instrumentation is not used to perform SR 3.3.1.2 when thermal power is greater than 50 percent RTP (Condition F). Currently, LCO 3.3.1 Condition F and its associated actions read as follows:

CONDITION F. UFM instrumentation not F.1 used to perform SR 3.3.1.2 when THERMAL POWER is

> 50% RTP.

AND REQUIRED ACTION

N 0 TE--------------

On I y required if four reactor coolant pumps (RCPs) are operating.

Initiate action to reduce THERMAL POWER to

98.4% RTP.

F. 2

NOTE--------------

AND Only required if three RCPs are operating.

Initiate action to reduce THERMAL POWER to

73.8% RTP.

COMPLETION TIME Immediately Immediately

CONDITION F. (continued)

F.3 REQUIRED ACTION

NOTE--------------

Only required if four RCPs are operating.

COMPLETION TIME Reset High Flux - High 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months Setpoint Allowable Value to s 103.3% RTP The licensee is proposing to revise TS 3.3.1 to permit the use of feedwater flow venturi measurements to perform SR 3.3.1.2 for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months before thermal power must be reduced and up to 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months before the high flux - high setpoint allowable value is reset. The licensee is also proposing to revise the current format, but retain the existing requirements. The revised LCO 3.3.1 Condition F will apply when all four RCPs are operating, and a new LCO 3.3.1 Condition G will apply when three RCPs are operating. The current notes will be removed from the required actions associated with Condition F, as they will be incorporated into the proposed Conditions F and G. The revised LCO 3.3.1 Conditions F and its associated actions will read as follows:

CONDITION REQUIRED ACTION COMPLETION TIME F. UFM instrumentation not F.1.1 used to perform Initiate action to reduce THERMAL POWER to s 98.4% RTP.

Immediately SR 3.3.1.2.

AND THERMAL POWER

> 50% RTP.

Four reactor coolant pumps (RCPs) operating.

AND F.1.2 Reset High Flux - High 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months Setpoint Allowable Value to s 103.3% RTP.

F.2.1 Perform SR 3.3.1.2 using calorimetric heat balance based on feedwater flow venturi readings normalized to the last UFM readings provided THERMAL POWER has been continuously maintained

> 90% RTP since the previous calorimetric heat balance based on UFM readings.

Immediately

CONDITION F. (continued) REQUIRED ACTION AND F.2.2 Initiate action to reduce THERMAL POWER to s 98.4% RTP.

AND F.2.3 Reset High Flux - High Setpoint Allowable Value to s 103.3% RTP.

COMPLETION TIME 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months since the last calorimetric heat balance based on UFM readings 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months since the last calorimetric heat balance based on UFM readings The new LCO 3.3.1 Conditions G and its associated actions will read as follows:

CONDITION G. UFM instrumentation not used to perform SR 3.3.1.2.

AND THERMAL POWER

> 50% RTP.

AND Three RCPs operating.

G.1 REQUIRED ACTION Initiate action to reduce THERMAL POWER to s 73.8% RTP.

2.3 Regulatory Requirements and Guidance COMPLETION TIME Immediately The categories of items required to be in the TSs are provided in Title 10 of the Code of Federal Regulations (1 O CFR) Section 50.36(c). As required by 10 CFR 50.36(c)(2)(i), the TSs will include LCOs, which are the lowest functional capability or performance levels of equipment required for safe operation of the facility. Per 10 CFR 50.36(c)(2)(i), when an LCO 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. The regulation at 1 O CFR 50.36(c)(3) requires TSs to include SRs, which are requirements relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the LCOs will be met. Also, 10 CFR 50.36(a)(1) states that a summary statement of the bases or reasons for such specifications, other than those covering administrative controls, shall also be included in the application, but shall not become part of the TSs.

Nuclear power plants are licensed to operate at a specified core thermal power. In this regard, Appendix K to 10 CFR Part 50 requires loss-of-coolant accident and emergency core cooling system analyses to assume "that the reactor has been operating continuously at a power level at least 1. 02 times the licensed power level" to allow for instrumentation error. Alternately, Appendix K allows these analyses to use an assumed power level less than 1.02 times the licensed power level, but not less than the licensed thermal power level, provided the proposed alternative value has been demonstrated to account for uncertainties due to power level instrumentation error. Consistent with the alternative in Appendix K, the licensee uses less than 1.02 times the licensed power level in its analyses for Davis-Besse (this was approved by the NRC with the power uprate amendment).

The NRC staff's guidance for review of the TSs is in Chapter 16, "Technical Specifications,

Revision 3, dated March 2010 (ADAMS Accession No. ML100351425), of NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants:

LWR [Light-Water Reactor] Edition." As described therein, as part of the regulatory standardization effort, the staff has prepared standard TSs for each of the light-water reactor nuclear designs. NUREG-1430, "Standard Technical Specifications: Babcock and Wilcox Plants," Revision 4.0, published April 2012 (ADAMS Accession No. ML12100A177), contains guidance on the standard format and content of the TSs applicable to Davis-Besse.

3.0 TECHNICAL EVALUATION

The NRC staff considered the regulations and guidance in Section 2.0 of this safety evaluation in its review. The staff also identified several precedents where other licensees were approved to operate at full power for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months when the UFM was not used to perform the calorimetric heat balance calculation (e.g., see ADAMS Accession Nos. ML13364A131, ML110691095, ML101830361, ML081540280, and ML17095A117).

3.1 UFM Allowed Outage Time The UFM system at Davis-Besse is not used to perform the heat balance calculation when any ultrasonic transducer is inoperable. Currently, when this occurs, the licensee must immediately initiate actions to reduce thermal power level. The proposed alternative would allow the licensee to delay the reduction in power for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , under certain conditions, to allow sufficient time for plant staff to make repairs to the UFM system, which may include planning, procuring, and installing replacement components. This 72-hour period is also referred to by the licensee as the allowed outage time (AOT) for the UFM.

The licensee performed a statistical evaluation on the difference between historical feedwater flow values obtained from the UFM and from the venturis. This statistical evaluation was based on a comparison of more than 3 years of feedwater flow data, recorded at 15 minute intervals, from the UFM and the venturis. The database for the statistical analysis included more than 100,000 data points. All the data included in the analysis were for measurements taken when thermal power was greater than 90 percent RTP. The licensee stated that the collected data exhibited random behavior with a growing bias over time following calibration, which was attributed to venturi fouling.

The application states:

Expressed in percent of nominal [feedwater] flow, the 72-hour change in the upper bounds of the dataset with a 95 percent probability and 95 percent confidence was calculated to be 0.00349 percent. Similarly, the 120-hour change was calculated to be 0.00375 percent.

The Davis-Besse power uprate was approved based on a power measurement uncertainty of 0.37 percent when using the UFM measurements to calculate the reactor thermal power. Over a 120-hour period, the change in accuracy (0.00375 percent) of the feedwater flow measurements using the venturis is very small. The results demonstrate that venturi-based feedwater flow values, normalized to UFM flow values obtained up to 120 hours0.00139 days 0.0333 hours 1.984127e-4 weeks 4.566e-5 months prior, can be used as input to the calorimetric heat balance calculation with the same degree of uncertainty as the UFM system. Thus, operation within the RTP limit is ensured when normalized venturi flow data is used to perform calorimetric calculations for the proposed UFM AOT of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .

Feedwater temperature is also used in the calculation of the mass flowrate of feedwater. The UFM based flowmeter includes a calculated temperature for this purpose. The venturi flow method receives the temperature input from the RTDs. The licensee compared the temperature measurements obtained from the feedwater RTDs and the UFM system. More than 94,000 differences in readings between the two systems were evaluated over the same time period as the evaluated flow measurements. The licensee stated the average difference between corresponding UFM and RTD temperature measurements was 0.3 degrees Fahrenheit, which is within the uncertainty of the UFM temperature measurements. Therefore, the licensee determined that use of measurements from the feedwater RTDs in lieu of the UFM will not impact the overall uncertainty of calculated reactor power.

The application states:

Feedwater venturi flow measurements may drift during the AOT period if fouling occurs. Fouling of the venturis would result in a conservative [feedwater] flow input to the calorimetric heat balance, thereby causing the reactor to be operated below the power level indicated by plant instrumentation. Sudden de-fouling during the AOT period is unlikely if stable power conditions are maintained. The proposed TS condition requiring that power be continuously maintained greater than 90 percent RTP throughout the AOT period is intended to ensure a stable power condition.

The NRC staff finds that the licensee's statistical evaluation of plant operating data adequately accounts for the combination of factors, such as gradual fouling or instrument drift, that can affect consistency of the instrument measurements. The evaluation demonstrated that using the feedwater flow venturi readings, normalized to the last UFM readings, adds negligible errors over the proposed 72-hour AOT for the UFM, provided that the power level has been continuously maintained at greater than 90 percent RTP. Thus, using the feedwater flow venturi readings, normalized to the last UFM readings, in the heat balance calculation will provide the same degree of accuracy as using the UFM readings over a 72-hour period. Therefore, the staff concludes that operation within the thermal power limits is ensured and 10 CFR 50, Appendix K, will continue to be met. The staff also notes that the proposed 72-hour AOT for the UFM is consistent with what has been approved for other licensees.

3.2 Reset of High Flux - High Setpoint The high flux - high setpoint trip provides protection for the design thermal overpower condition based on the measured fast neutron flux. Currently, if the UFM is not used to perform the heat balance calculation the licensee must reset the high flux - high setpoint allowable value to less than or equal to 103.3 percent of RTP within 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months . The setpoint change is to account for the increased uncertainty in the neutron flux instrumentation when calibrated using the venturi-based heat balance calculation.

The licensee proposes to also extend the completion time for resetting the high flux - high setpoint to 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months since the last calorimetric heat balance based on UFM readings. This would only be used when the licensee can extend the AOT for the UFM to 72-hours. The licensee stated that the drift allowance (0.225 percent power every 92 days) used in setpoint calculations for the RPS high flux trip indicates that the instruments will remain calibrated for a period of time considerably longer than 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months . Based on this, the NRG staff finds the proposed 82-hour completion time to reset the high flux - high setpoint to be acceptable.

3.3 Technical Specification Changes SR 3.3.1.2 requires that the licensee compare the result of the calorimetric heat balance calculation to power range channel output every 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . LCO 3.3.1 requires, in part, the UFM instrumentation to be used to perform SR 3.3.1.2 when thermal power is greater than 50 percent of RTP. Currently, LCO 3.3.1 Condition F applies when the thermal power is greater than 50 percent of RTP and the UFM is not used to perform SR 3.3.1.2. If four RCPs are operating when Condition F applies, the licensee is required to initiate action to: ( 1) reduce thermal power to less than or equal to 98.4 percent of RTP immediately and (2) reset the high flux - high setpoint allowable value to less than or equal to 103.3 percent of RTP within 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months . If three RCPs are operating when Condition F applies, the licensee is required to initiate action to reduce thermal power to less than or equal to 73.8 percent of RTP immediately.

The licensee proposed to revise the current format but retain the existing requirements associated with LCO 3.3.1 Condition F. If the UFM is not used to perform SR 3.3.1.2 and thermal power is greater than 50 percent of RTP, then the revised Condition F will apply when four RCPs are operating and the new Condition G will apply when three RCPs are operating.

The current notes regarding the number of RCPs operating will be removed from the required actions, as they are incorporated into the proposed LCO 3.3.1 Conditions F and G.

The licensee also proposed to add an alternative to the required actions for the revised LCO 3.3.1 Condition F to accommodate a 72-hour AOT for the UFM. The alternative required action would be to perform SR 3.3.1.2 using a calorimetric heat balance based on feedwater flow venturi readings normalized to the last UFM readings, provided thermal power has been continuously maintained greater than 90 percent RTP since the previous calorimetric heat balance based on UFM readings immediately (new required action F.2.1 ). If that action is taken, then the requirement to initiate action to reduce thermal power to less than or equal to 98.4 percent RTP (new required action F.2.2) could be postponed up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months since the last calorimetric based on UFM readings. Additionally, the resetting of the high flux - high setpoint (new required action F.2.3) could be postponed up to 82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months since the last calorimetric heat balance based on UFM readings.

The NRG staff reviewed the proposed TS changes. No changes are being proposed to LCO 3.3.1. Therefore, the LCO continues to specify the lowest functional capability or performance levels of equipment required for safe operation of the facility, as required by 1 O CFR 50.36(c)(2)(i). The proposed changes modify the remedial actions to be taken if the LCO is not met, by adding an alternative set of required actions. The regulations do not provide details on the content of the remedial actions. As discussed in Sections 3.1 and 3.2 of this safety evaluation, the staff determined that this alternative set of required actions is acceptable, and they are consistent with regulatory requirements. In addition, the presentation, format, and terminology in the proposed TS changes are consistent with NUREG-1430, Revision 4.0.

The regulations at 10 CFR 50.36 require TSs to include LCOs, SRs, and other items. The proposed changes modify the conditions, required actions, and completion times applicable when the UFM instrumentation is not used to perform the comparison of the calorimetric heat balance calculation to power range channel output required by SR 3.3.1.2. The TSs continue to specify the LCO and to specify the remedial measures to be taken if one of these requirements is not satisfied. The TSs continue to specify the appropriate SRs for tests and inspections to ensure the necessary quality of affected structures, systems, and components is maintained.

Therefore, the NRC staff finds that the proposed TS changes meet the requirements of 1 O CFR 50.36(c)(2)(i) and 50.36(c)(3).

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Ohio State official was notified September 20, 2017, of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes requirements with respect to the installation or use of facility components located within the restricted areas as defined in 10 CFR Part 20 and changes surveillance requirements. 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, which was published in the Federal Register on March 14, 2017 (82 FR 13665), that the amendment involves no significant hazards consideration, and there has been no public comment on such finding. 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 Contributors: Gursharan Singh, NRR Ma~ar~Chemo~NRR Fred Forsaty, NRR Date of issuance: October 19, 2017

SUBJECT:

DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 - ISSUANCE OF AMENDMENT REVISING TECHNICAL SPECIFICATION REQUIREMENTS FOR ULTRASONIC FLOW METER OUTAGE TIME (CAC NO. MF9080, EPID L-2017-LLA-0167) DATED OCTOBER 19, 2017 DISTRIBUTION:

PUBLIC LPL3 R/F RidsNrrDorlLpl3 Resource RidsRgn3MailCenter Resource RidsNrrLASRohrer Resource RidsAcrs_MailCTR Resource RidsNrrPMDavisBesse Resource RidsNrrDssStsb Resource RidsNrrDssSrxb Resource RidsNrrDeEicb Resource GSingh, NRR FForsaty, NRR MChernoff, NRR ADAMS A ccess1on N ML17270A112

0.

b 1y memo **b 1yema1 OFFICE DORL/LPL3/PM DORL/LPL3/LA DSS/SRXB/BC**

DE/El CB/BC*

NAME BPurnell SRohrer EOesterle MWaters DATE 9/29/17 9/28/17 8/28/17 8/17/17 OFFICE DSS/STSB/BC(A)* OGC-NLO DORL/LPL3/BC DORL/LPL3/PM NAME JWhitman DRoth DWrona BPurnell DATE 8/25/17 10/11/17 10/19/17 10/19/17 OFFICIAL RECORD COPY

v t e Letter Sequence Approval
CAC:MF9080, (Approved, Closed) EPID:L-2017-LLA-0167, (Approved, Closed)
Initiation Acceptance... Administration Questions Answers Results Approval Other:
MONTHYEAR2017-10-19 [Table View]

ML17270A112

Text

SUBJECT:

Dear Mr. Bezilla:

Enclosures:

Attachment:

1.0 INTRODUCTION

2.0 REGULATORY EVALUATION

2.1 Background

3.0 TECHNICAL EVALUATION

4.0 STATE CONSULTATION

5.0 ENVIRONMENTAL CONSIDERATION

6.0 CONCLUSION

SUBJECT:

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