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#REDIRECT [[L-2014-216, License Amendment Request No. 231, Application to Revise Technical Specifications to Revise Ultimate Heat Sink Temperature Limit]]
| number = ML14196A006
| issue date = 07/10/2014
| title = License Amendment Request No. 231, Application to Revise Technical Specifications to Revise Ultimate Heat Sink Temperature Limit
| author name = Kiley M W
| author affiliation = Florida Power & Light Co
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000250, 05000251
| license number = DPR-031, DPR-041
| contact person =
| case reference number = L-2014-216
| document type = Letter, License-Application for Facility Operating License (Amend/Renewal) DKT 50, Technical Specifications
| page count = 21
| project =
| stage = Request
}}
 
=Text=
{{#Wiki_filter:0FPL.10 CFR 50.90L-2014-216July 10, 2014U.S. Nuclear Regulatory CommissionATTN: Document Control DeskWashington, DC 20555-0001Turkey Point Units 3 and 4Docket Nos. 50-250 and 50-251Renewed Facility Operating License Nos. DPR-31 and DPR-41
 
==Subject:==
License Amendment Request No. 231, Application to Revise TechnicalSpecifications to Revise Ultimate Heat Sink Temperature LimitPursuant to 10 CFR 50.90 and 10 CFR 50.91 (a)(5), Florida Power & Light Company (FPL)hereby requests an amendment to the Technical Specifications (TS) for the Turkey Point NuclearPlant (Turkey Point), Units 3 and 4.The proposed amendment would revise the ultimate heat sink (UHS) water temperature limitfrom I 00°F to 1040F. The cooling canal system (UHS) temperature has been recently trendinghigher than historical averages and has approached the current limit. Therefore, FPL requests atimely review of this application because of the potential for the current limit to be exceeded.The enclosure to this letter contains a description of the proposed change and includes a nosignificant hazards determination and environmental considerations.There are no new commitments made in this submission.FPL requests that this application be approved by August 30, 2014.The proposed change has been evaluated in accordance with 10 CFR 50.91(a)(1) using criteria in10 CFR 50.92(c) and it has been determined that this change involves no significant hazardsconsideration.The Turkey Point Plant Nuclear Safety Committee has reviewed and approved the proposed licenseamendment. In accordance with 10 CFR 50.91(b)(1), a copy of this letter is being forwarded to theState Designee of Florida.Florida Power & Light Company9760 SW 344th St., Florida City, FL 33035 L-2014-216Page 2 of 2If you have any questions or require additional information, please contact Mr. Robert Tomontoat 305-246-7327.1 declare under penalty of perjury that the foregoing is true and correct.Executed on: 7/10/14Very truly yours,T. P Qis3yMichael KileyVice PresidentTurkey Point Nuclear Plant
 
==Enclosure:==
Application to Revise Technical Specifications to Revise Ultimate Heat SinkTemperature Limitcc: USNRC Regional Administrator, Region IIUSNRC Project Manager, Turkey Point Nuclear PlantUSNRC Senior Resident Inspector, Turkey Point Nuclear PlantMs. Cindy Becker, Florida Department of Health L-2014-216EnclosurePage 1 of 17Turkey Point Units 3 and 4License Amendment Request No. 231Application to Revise Technical SpecificationsTo Revise Ultimate Heat Sink Temperature LimitEnclosure1. Description2. Proposed Change3. Background4. Technical Analysis5. Regulatory Safety Analysis5.1 No Significant Hazards Consideration5.2 Applicable Regulatory Requirements/Criteria6. Environmental Consideration7. Conclusions8. Precedent9. AttachmentProposed Technical Specification Page 3/4 7-17 Mark-up L-2014-216EnclosurePage 2 of 171.0 DescriptionFlorida Power & Light Company (FPL) proposes a revision to the Ultimate Heat Sink (UHS)temperature limit from 100°F to 104'F.2.0 Proposed ChangeThe proposed change would revise the UHS temperature limit in Technical Specification (TS)3/4.7.4, Ultimate Heat Sink, from 100°F to 104'F. In addition, a new Surveillance Requirement(SR) would require more frequent monitoring (at least once per 6 hours) when UHS temperatureexceeds I 00°F.2.1 Current TS and BasesCurrent TS 3/4.7.4, addresses UHS system operability by requiring that the averagesupply temperature to the Intake Cooling Water (ICW) system be within specified limits:Limiting Condition for Operation (LCO) 3/4.7.4 states:The ultimate heat sink shall be OPERABLE with an average supply watertemperature less than or equal to I 00°F.APPLICABILITY is Modes 1, 2, 3, and 4.The ACTION states:With the requirements of the above specification not satisfied, be in at least HOTSTANDBY within 12 hours and In COLD SHUTDOWN within the following 30hours. This ACTION shall be applicable to both units simultaneously.SR 4.7.4 states:The ultimate heat sink shall be determined OPERABLE at least once per 24 hoursby verifying the average supply water temperature* to be within its limit.The asterisk (*) refers to a footnote that reads:Portable monitors may be used to measure the temperature.TS BasesThe limit on Ultimate Heat Sink (UHS) temperature in conjunction with theSURVEILLANCE REQUIREMENTS of Technical Specification 3/4.7.2 will ensure that L-2014-216EnclosurePage 3 of 17sufficient cooling capacity is available either: (1) To provide normal cool down of thefacility, or (2) To mitigate the effects of accident conditions within acceptable limits.FPL has the option of monitoring the UHS temperature by monitoring the temperature inthe ICW system piping going to the inlet of the CCW Heat Exchangers. Monitoring theUHS temperature after the ICW but prior to CCW Heat Exchangers is considered to beequivalent to temperature monitoring before the ICW Pumps. The supply water leavingthe ICW Pumps will be mixed and therefore, it will be representative of the bulk UHStemperature to the CCW Heat Exchanger inlet. The effects of the pump heating on thesupply water are negligible due to low ICW head and high water volume. Accordingly,monitoring the UHS temperature after the ICW Pumps but prior to the CCW HeatExchangers provides an equivalent location for monitoring the UHS temperature.With the implementation of the CCW Heat Exchanger Performance Monitoring Program,the limiting UHS temperature can be treated as a variable with an absolute upper limit of100'F without compromising any margin of safety. Demonstration of actual heatexchanger performance capability supports system operation with postulated canaltemperatures greater than 1 00°F. Therefore, an upper TS limit of I 00'F is conservative.2.2 Proposed TS and Bases ChangesThe proposed revision to TS 3/4.7.4:LCO 3/4.7.4 would state:The ultimate heat sink shall be OPERABLE with an average supply watertemperature less than or equal to 1040F.APPLICABILITY remains unchanged.ACTION required remains unchanged except for the correction of a typographical error.The capitalized word 'In' before the words 'COLD SHUTDOWN' is properly reduced tolower case because it is not at the beginning of the sentence. This is an administrativechange that does not alter the required action. The typographical error was introducedwhen FPL provided the NRC retyped pages for License Amendments 260 and 255.Current SR 4.7.4 would be revised as follows:4.7.4 The ultimate heat sink shall be determined OPERABLE:a. At least once per 24 hours by verifying the average supply water temperature*to be within its limit.SR 4.7.4.b would be added:
L-2014-216EnclosurePage 4 of 17b. Verify average supply water temperature* to be within the limit at least onceper 6 hours when water temperature exceeds 100°F.The asterisk (*) refers to a footnote that remains unchanged.A mark-up of the proposed TS revision is attached.Appropriate supporting TS Bases changes will also be performed in accordance with theTS Bases Control Program (TS 6.8.4.i).3.0 BackgroundTurkey Point Units 1, 2, 3 and 4 use a closed system of cooling canals to support operation of thepower plants. For nuclear units 3 and 4, the cooling canal system provides the coolant for theCirculating Water (CW) system and the Ultimate Heat Sink (UHS) for the Intake Cooling Water(ICW) system. The CW system provides cooling water to the main plant condensers. The ICWsystem removes heat loads from the Component Cooling Water (CCW) system during normaland accident conditions to support both reactor and containment heat removal requirements, andspent fuel cooling requirements. FPL proposes to revise the Turkey Point Unit 3 and Unit 4licensing basis by amending Appendix A of Renewed Facility Operating Licenses DPR-31 andDPR-41 for Units 3 and 4 to incorporate an increase in the maximum allowable UHStemperature contained in TS 3/4.7.4.In June 2014, UHS temperatures almost approached the currently analyzed maximumtemperature of 100°F. Engineering and environmental analysis has determined that the coolingwater heat transfer capability is diminished due to the presence of a higher than normal algaecontent. While immediate eradication of the algae is possible, there are biological impacts froma sudden algae die off and decay that must be mitigated and/or avoided. Thus, a controlledchemical treatment of the canal system over the course of several weeks is planned to graduallyreduce the near-term algae content and improve heat transfer efficiency. If UHS temperatureswere to exceed the current I 00'F TS limit during the treatment period and ensuing summermonths, a plant shutdown would have to be initiated in accordance with the action requirementsof TS 3/4.7.4, increasing the possibility of a shutdown transient. Adoption of the proposed TSchange would allow continued plant operation with measured UHS temperatures less than orequal to 104'F.3.1 UHS Description and Design BasisThe UHS for Turkey Point Units 3 and 4 is provided by a closed cooling canal systemlocated south of the plant. The canal system also serves the cooling needs of TurkeyPoint fossil units 1 and 2. The canal system occupies an area approximately 2 miles wideby 5 miles long and includes 168 miles of earthen canals covering approximately 6100 L-2014-216EnclosurePage 5 of 17acres (4370 acres of water surface). The average canal depth is 2.8 feet. Total watervolume in the cooling canals is approximately 12,300 acre-feet (4 billion gallons). Thecanals receive heated water from the fossil and nuclear plant equipment cooling systemsat one end and supply cooled water at the other end for reuse. The discharge canaldistributes the outflow into 32 feeder canals for cooling. Water in the feeder canals flowssouth and discharges to a single collecting canal that distributes water to six return canals.Water in the return canals flows north to the plant intake. The entire "water circuit,"plant discharge back to plant intake, is 13.2 miles and takes approximately 44 hours tocomplete. Temperature rise across the plant, from intake to discharge, averages 15-307Fdepending upon the number of fossil and nuclear units in operation, unit load, and variousother factors. The average intake temperature is 2.5'F above the average ambient airtemperature.The units 3 and 4 CW and ICW systems pump the canal water to the various plantcooling water systems. The CW system (4 pumps) provides cooling water to the mainplant condenser water boxes. The ICW system (sometimes called the service watersystem at other facilities) has three 100% capacity pumps and provides cooling water tothree 50% capacity safety related CCW heat exchangers and two non-safety relatedTurbine Plant Cooling Water (TPCW) heat exchangers. In the event of an accident, thenon-safety related TPCW heat exchangers are automatically isolated so that all ICW flowis diverted to the safety related CCW heat exchangers. The CCW system is anintermediate cooling system serving normal and emergency equipment loads. It providesthe heat sink for the Chemical and Volume Control system (CVCS), the Spent Fuel Pit(SFP) Cooling system, the Normal Containment Cooling (NCC) system and variousReactor Coolant system (RCS) components during normal plant operation. The CCWsystem provides a heat sink for the Residual Heat Removal (RHR) system, EmergencyContainment Cooling (ECC) system, and the High Head Safety Injection (HHSI) PumpCoolers during design basis accident conditions.During a design basis accident (i.e., a loss-of-coolant accident), one ICW pump willprovide all the cooling water required to two CCW heat exchangers for heat removal.The analyses of record assume that the cooling water supplied by the ICW pumps to theinlet of the CCW heat exchangers does not exceed I 00°F.The large break loss-of-coolant accident (LOCA) provides the design basis heat removalrequirements for the CCW system with post-accident containment heat removalproviding the bulk of the system heat load. Post-accident containment heat removal isprovided by the ECC system and the Containment Spray (CS) system.The ECC system uses the CCW system as a heat sink which is available upon ECC fancooler actuation. The CS system initially relies on heat transfer to the lower temperaturespray droplets as they pass through the containment atmosphere during the injectionphase of emergency core cooling system operation. Following the transfer to long termcontainment sump recirculation, the CS system heat load is transferred to CCW system L-2014-216EnclosurePage 6 of 17via the RHR system heat exchangers. The HHSI pump bearings are also cooled by theCCW system.4.0 Technical Analysis4.1 Basis for Proposed Technical Specification ChangesThe proposed TS change increases the maximum allowable UHS temperature foroperation of Units 3 and 4. Adoption of the proposed TS change will allow continuedplant operation provided the measured UHS temperature does not exceed 104'F. Themaximum allowable canal temperature would be 104'F (analytical limit) minus themeasurement instrument uncertainty.The maximum allowable UHS temperature satisfies Criterion 3 of 10 CFR50.36(c)(2)(ii). Accordingly, justification of the proposed TS change requires 1)confirmation that the increased UHS temperature continues to afford adequate post-accident heat removal capability, 2) confirmation that plant-specific assumptionspreviously credited in evaluating special events and regulatory issues are upheld by theproposed increase in UHS temperature, 3) confirmation that reliability of safety relatedequipment will not be impacted by the higher service temperature limit, and 4)confirmation that canal system performance will not be affected by the higher allowedwater body temperatures.4.1.1 Impact on Heat Removal/Accident Analysis AssumptionsSection 14.3.4.3.4 of the Updated Final Safety Analysis Report (UFSAR)provides the results of the containment integrity analyses performed for the largebreak LOCA and main steam line break (MSLB) accident inside containment.The LOCA containment integrity analyses are performed for a double-ended hotleg (DEHL) break and a double-ended pump suction (DEPS) break which is thelimiting cold leg break location for Turkey Point Units 3 and 4. The MSLBcontainment integrity analysis is performed for a 1.0 ft2 split break plus theadditional mass and energy release resulting from failure of the main steam checkvalve on the faulted steam generator to isolate the non-faulted steam generatorsteam lines. The containment pressure profile for the DEHL break analysis ispresented in UFSAR Figure 14.3.4.3-3. The containment pressure profile for theDEPS transient is presented in UFSAR Figure 14.3.4.3-5. The containmentpressure transient for the limiting MSLB event is shown in UFSAR Figure14.3.4.3-7.For the LOCA analyses, the containment pressure is shown to initially peak andbegin to decrease due to heat absorption by the containment internal structures,prior to active heat removal via operation of the safeguards equipment. In each L-2014-216EnclosurePage 7 of 17case, the heat removal provided by the passive containment heat sinks is sufficientto prevent immediate containment overpresurrization. The peak containmentpressure for the DEHL break occurs at 20 seconds prior to operation of the activecontainment heat removal systems which occurs at 50 seconds for the ECCsystem and 60 seconds for the CS system. Operation of the safeguards systems issufficient to remove the additional decay heat transfer to containment that occursfollowing the initial blowdown phase. For the DEPS break, the passivecontainment heat sinks are similarly capable of preventing immediatecontainment overpressurization from the initial break release. However, as shownin Figure 14.3.4.3-5, operation of the containment heat removal systems iseventually required to prevent containment overpressurization from thesubsequent decay heat release following the initial blowdown and reflood phases.At 24 hours following the DEPS break, containment pressure has been reduced toa value well below 50 percent of the peak calculated value.For the MSLB analysis, the immediate heat removal capability provided by thepassive containment heat sinks prevents an initial spike in containment pressureand provides the immediate protection for the containment boundary until theactive containment heat removal systems are eventually actuated. The ECCsystem is actuated at 47.1 seconds and the CS system is actuated at 87.1 seconds.These systems provide additional heat removal capability to remove the continuedmass and energy released to containment via the failed main steam check valveand faulted steam generator break opening.Performance of the passive containment heat sinks is not affected by the proposedchange in UHS temperature. The UFSAR containment integrity analyses wereperformed at an initial containment atmosphere temperature of 130'F whichbounds the maximum containment atmosphere temperature allowance in the plantTS.A technical evaluation of the CCW system was also performed to determine ifECC system and CS system performance would be affected by the proposedchange in UHS temperature. It was determined that adequate margin exists in theCCW system such that post-accident CCW system supply and return temperatureswould remain as currently analyzed in the containment integrity analyses. Thisensures that the peak containment pressure is not altered bythe proposed TSchange. The technical evaluation confirmed that adequate CCW design marginwould remain under the proposed operating conditions to allow a reasonabledegree of equipment degradation to occur while demonstrating that the affectedsafety related components on the accident unit could continuously perform theirdesign function as currently analyzed.The Maximum Hypothetical Accident for Turkey Point involves an accidentrequiring safety injection (SI) on one unit which is accompanied by a sequential L-2014-216EnclosurePage 8 of 17trip of the non-accident unit together with loss of all AC power to both nuclearunits. This scenario provides the most limiting design condition for theemergency power system. A requirement for the non-accident unit is thatadequate containment heat removal exists to prevent an inadvertent SI actuationduring the shutdown due to increased transmitter errors caused by highercontainment temperature conditions. The NCC fan coolers were replaced as partof Extended Power Uprate (EPU) modifications. The NCC modificationconfirmed that adequate heat removal would be available on the non-accident unitunder EPU operating conditions. Since the proposed change in maximum UHStemperature does not affect containment heat sink performance or thermalperformance of the CCW system, there is no decrease in the available margin toSI actuation on the non-accident unit.The above assessment confirms that the proposed increase in UHS temperaturewill continue to satisfy the accident analysis assumptions for containment heatremoval.4.1.2 Impact on Accident Mitigation, Anticipated Operational Occurrences, andSafe ShutdownThe proposed change in UHS temperature will impact the inlet and outlettemperatures of the safety related ICW system. The ICW system cools the safetyrelated CCW system which, in turn, cools the safety related equipment requiredfor accident mitigation, anticipated operational occurrences, and safe shutdown.As indicated in Section 4.1.1, above, the ECC system is credited in the plantsafety analysis for post-accident containment heat removal. Evaluationsperformed in response to Generic Letter 96-06 demonstrate that the CCW systemserving the ECC units is not susceptible to water hammer or overpressurization ofisolated piping inside containment following a design basis accident such thatcontainment integrity could be compromised. These evaluations are not affectedby the proposed UHS limit because post-accident thermal performance of theCCW system is not diminished by the change in ICW system operation.The impact of the increased UHS temperature limit on special events that theplant must be designed to withstand (e.g., station blackout, TS required cool downto cold shutdown conditions) is similarly unaffected because CCW systemperformance remains encompassed by the existing evaluations which demonstratethat the required equipment is capable of performing their design functions.Therefore, plant specific assumptions previously credited in evaluating specialevents and regulatory issues are not impacted by the proposed increase in theUHS temperature limit.
L-2014-216EnclosurePage 9 of 174.1.3 Impact on Plant Equipment ReliabilityThe proposed TS change increases the maximum allowable (measured) ICWsystem supply temperature from 1 00°F to 104'F. This change does not alter anyassumptions on which the plant safety analysis is based. The affectedcomponents were originally designed with margin that allows for cooling watertemperatures greater than the plant design basis of 1 00°F, although no credit hadpreviously been taken for this margin. A review of ICW system componentsbetween the ICW pumps and the CCW and TPCW Heat Exchangers wasperformed for the increased UHS analytical temperature of 104'F. The specifieddesign temperature for many of the components is 100°F which corresponds to thecurrent UHS TS temperature limit. However, review of information specific tothe affected components indicates that all ICW components between the pumpand the heat exchangers are rated for service temperatures well in excess of100F. A review of ICW pump materials indicates that the projected 4°F increasein process fluid would have an insignificant affect on the materials in contact withthe fluid, including thermal expansion and material temperature service rating.In addition to material compatibility, a review of ICW pump operating parameterswas performed for the increased UHS temperature condition. It was confirmedthat reliability of the ICW pumps would not be adversely affected by the decreasein available net positive suction head associated with increased canal watertemperatures.The component reviews confirmed that a reasonable degree of margin forequipment degradation still exists such that the affected safety related componentscan continuously perform their design function at cooling water temperatures upto 1040F. Additionally, new limits for heat exchanger cleanliness will beprocedurally controlled to ensure that the affected components would continue tofunction at the increased cooling water temperature.4.1.4 Impact on Canal System PerformanceThe Turkey Point units (fossil and nuclear) use the canal system like a radiator,discharging heated water at one end and withdrawing cooled water at the otherend for reuse. The heated discharge effluent is distributed to 32 feeder canals.Water in the feeder canals flows south, discharging into a single collector canalthat distributes water to six return canals. Water in the return canals flows northto the plant intake. The transit time through the canal system is approximately 44hours. Flows attributable to the nuclear units amount to approximately 1.3million gallons per minute. Incident rainfall, some plant storm water runoff,treated process wastewater from the municipal supply, and, possibly, groundwaterinflows compensate for evaporative cooling losses from this system.
L-2014-216EnclosurePage 10 of 17The thermodynamic performance of the canal system is complex and influencedby many processes including:1. Heat rejected to the canal by operating fossil and nuclear units,2. Solar radiant heating,3. Radiative cooling of the water body at night,4. Conduction and convection of heat from the water body to the atmosphere,5. Heat carried away by evaporation,6. Heat transfer between the water body and the interior of the earth,7. Cooling of the water body via precipitation, and8. Cooling of the water body by ground water seepage.Items 2 through 5 are influenced by weather parameters in effect such as dry bulbtemperature, dew point, wind speed, and cloud cover. The temperature of thewater at the discharge point does not comingle with the intake temperature andthere is no possibility of short circuiting the cooling canal function. Thedischarged water must travel around the canal system prior to returning to theintake structure. The intake temperature is directly affected by the prevailingenvironmental conditions that exist during the approximate 2-day transit timefrom the discharge point to the intake point which are inherent characteristics ofthe canal system heat sink.Since variability in weather conditions can affect canal heat transfer efficiency,the proposed SR requires that more frequent UHS temperature monitoring beperformed when the UHS temperature is greater than 1 000F to ensure that themaximum measured temperature does not exceed the 104'F limit. The proposed6-hour time-frame to perform follow-up UHS temperature measurements isreasonable based on a review of actual canal temperature data recorded on July 4,2014.4.2 Analysis Input Changes and Methodology for Proposed ChangeTS 3/4.7.2 provides the LCO and the SR for the CCW system. SR 4.7.2.b requires in partthat a performance test of the CCW heat exchangers be conducted at least once per 31days to verify the post-accident heat removal capability. This SR is conducted bymeasuring the CCW heat exchanger inlet/outlet temperatures and ICW flow, and L-2014-216EnclosurePage 11 of 17calculating the associated heat exchanger tube resistance using the Turkey Point[X3/HX4 computer program.The Turkey Point HX3/HX4 computer program determines CCW heat exchangerperformance based on the conservation of energy equations for heat transfer between theLCW and CCW systems, and the performance equation for the heat exchanger. The heatgain (to the ICW system) is equal to the heat lost (from the CCW system) and is alsoequal to the heat transferred within the heat exchanger as described by the total surfacearea, the heat exchanger heat transfer coefficient, and the logarithmic mean temperaturedifference, LMTD.The HX3/H-X4 computer program allows for fouling (or tube resistance (TR)) above thefouling factor used in the safety analyses provided that the actual UHS temperature islower than the maximum allowed temperature predicted for the current heat exchangerconditions. Based on the surveillance data, the program determines the current CCWheat exchanger TR and provides the user with a maximum allowable UHS temperatureassociated with that TR. Provided the maximum allowable UHS temperature ismaintained for the current TR, the CCW heat exchangers will support at least as muchheat transfer as required by the plant safety analyses.The figure below illustrates the relationship between CCW heat exchanger TR and UHStemperature used by the HX3/HX4 program. As shown, the TR calculated by theprogram will be conservatively lower than the TR used in the safety analysis for all UHStemperatures:
L-2014-216EnclosurePage 12 of 17Tube Resistance Limits0.0050.0045I' 0.004.0.00350.003SafM y s TR @ 100 OF0.002655 100 OF Limit-0.0025I-0.002292 104 OF LimitU.IAJL0.0015I II II I70 75 80 85 90 95 100 105 110ICW Temperature (QF)Figure 3.5-1: Tube Resistance LimitNote that a 3°F reduction in the maximum allowable UHS temperature calculated by theprogram is applied to provide operational margin to the analytical limit. When themeasured UHS temperature is within 3 degrees of the average performance of the twomost fouled heat exchangers, Operations personnel declare the most fouled heatexchanger out of service and request that it be cleaned by plant Maintenance personnel.Cleaning frequency is dictated by both actual plant conditions as described and stationdesires to create a predictable schedule for maintenance resources.In order to develop the HX3/HX4 computer program, a design basis case needs to beestablished. The program requires four inputs to define a design basis case: 1) CCW inlettemperature, 2) CCW outlet temperature, 3) ICW flow rate, and 4) heat load. The designbasis case is determined by first finding the most limiting safety analysis case. Once themost limiting case is found, several iterations are performed on calculating the TR andmaximum allowable temperatures. The design basis cases embedded in the program andverification cases are created to verify the CCW heat exchangers, at a minimum, removethe necessary heat for the corresponding safety and cool down scenarios at a given UHStemperature.
L-2014-216EnclosurePage 13 of 17The HX3/HX4 computer program is used as the technical basis supporting the requestedincrease in UHS temperature limit. Analyses were performed to confirm continuedcompliance with the containment integrity analysis, and continued capability to completea plant cool down to cold shutdown conditions within required time limits.Table 3.5-1 identifies the UHS temperatures that were used in the current and revisedanalyses.Table 3.5-1 UHS Temperatures Used in CCW Thermal AnalysesCurrent RevisedTemperature (OF) Temperature Time Interval Type of Analysis Used InTempeature(°F) (OF)92 95.16 Spring/Fall Plant Cool Down97 98.2 Summer Plant Cool Down100 104 Year-Round AccidentDetails of the analyses are discussed below.Safety Analyses ScenariosThe calculation for CCW heat exchanger performance was revised using the HX3/HX4computer program to demonstrate that the CCW heat exchangers can remove thenecessary post-accident containment heat load for the LOCA and MSLB containmentintegrity analyses. The revised calculation uses the program to calculate the TR atdifferent UHS temperatures (i.e. 104'F). By using the conservation of energy equationsfor heat transfer between the ICW and CCW systems and the performance equation forthe heat exchanger, it calculates the heat transfer capability of the heat exchanger. If thepredicted heat exchanger heat removal is greater than the safety analysis heat load, thenthe CCW heat exchangers are capable of removing the safety analysis heat load at thegiven UHS temperature. Since neither the HX3/HX4 Program Line, nor theadministrative limit has changed, the CCW heat exchangers will support at least as muchheat transfer as assumed during the plant safety analyses. As shown in Figure 3.5-1, thedesign basis heat load can be adequately dissipated to maintain containment integritywithout any changes in CCW system flow rates, or CCW supply and return temperatures.Accordingly, the safety analyses remain unchanged.Plant Cool Down ScenariosThe plant cool down analyses for Turkey Point use a "best estimate" approach todemonstrate the capability to complete a cool down to cold shutdown conditions withinthe required time frame. The limiting scenario involves an Appendix R cool down during L-2014-216EnclosurePage 14 of 17the summer season. The scenario models the cool down using a single CCW trainalignment (1 CCW pump to 2 CCW heat exchangers) with only one RHR heat exchangerin service.The revised calculation maintains the same CCW heat load condition but increases theUHS temperature from 97'F to 98.2°F. The higher UHS temperature value of 98.2°F isbased on historical UHS data for a two year period between 2012 and 2014, and reflects a95/95 tolerance limit. The revised calculation demonstrates that the cool down scenariocan still be accomplished within the required time period with increased UHStemperatures.A plant cool down to cold shutdown conditions for TS compliance was also re-analyzedwith a higher UHS temperature. The new UHS temperature values similarly reflect a95/95 tolerance limit. The revised calculation demonstrates that the normal plant cooldown to cold shutdown is still within the 36-hour time duration required by TS.5.0 Regulatory Analysis10 CFR 50.91 (a)(l) requires that licensee requests for operating license amendments beaccompanied by an evaluation of significant hazards posed by the issuance of the amendment.FPL has evaluated this proposed amendment with respect to the criteria given in 10 CFR50.92(c).A necessary element of plant operation is the removal of the heat generated by the powergeneration process. This includes both the removal of heat during routine operation and removalof heat as part of mitigating accidents and transients that are postulated to occur.This license amendment request proposes to increase the temperature limit for the UHS from itscurrent limit of I00F to 104'F.FPL has evaluated whether or not a significant hazards consideration is involved with theproposed change. A discussion of these standards as they relate to this change request isprovided below:5.1 No Significant Hazards Consideration Evaluation5.1.1 Does the proposed change involve a significant increase in the probabilityor consequences of an accident previously evaluated?Response: NoThe ultimate heat sink (UHS) is not an accident initiator. An increase inUHS temperature will not increase the probability of occurrence of an L-2014-216EnclosurePage 15 of 17accident. The proposed change will allow plant operation with a UHStemperature less than or equal to 104'F. Maintaining UHS temperatureless than or equal to 104'F ensures that accident mitigation equipment willcontinue to perform its required function, thereby ensuring theconsequences of accidents previously evaluated are not increased.Therefore, the proposed change does not involve a significant increase inthe probability or consequences of an accident previously evaluated.5.1.2 Does the proposed change create the possibility of a new or different kindof accident from any accident previously evaluated?Response: NoThe proposed change will not install any new or different equipment ormodify equipment in the plant. The proposed change will not alter theoperation or function of structures, systems or components. The responseof the plant and the operators following a design basis accident isunaffected by this change. The proposed change does not introduce anynew failure modes and the design basis heat removal capability of thesafety related components is maintained at the increased UHS temperaturelimit. Therefore, the proposed change will not create the possibility of anew or different kind of accident from any previously evaluated.3. Does the proposed change involve a significant reduction in the margin ofsafety?Response: NoThe increase in UHS temperature will not adversely affect design basisaccident mitigation equipment performance. It was determined thatadequate margin exists in the CCW system such that post-accident CCWsystem supply and return temperatures would remain as currently analyzedin the containment integrity analyses such that the peak containmentpressure is not altered by the proposed TS change. The technicalevaluation confirmed that adequate CCW design margin would remainunder the proposed operating conditions to allow a reasonable degree ofequipment degradation to occur while demonstrating that the affectedsafety related components could continuously perform their designfunction as currently analyzed. Therefore, the proposed change does notinvolve a significant reduction in the margin of safety.
L-2014-216EnclosurePage 16 of 17ConclusionBased on the above, FPL concludes that the proposed amendment presents no significanthazards consideration under the standards set forth in 10 CFR 50.92(c), and accordingly,a finding of no significant hazards consideration is justified.5.2 Applicable Regulatory Requirements/Criteria10 CFR 50, Appendix A General Design Criteria (GDC) 44, 45 and 46 apply to the coolingwater system for transfer of heat from structures, systems, and components important to safety toan ultimate heat sink. Turkey Point was initially licensed to the 1967 proposed draft GDC.ICW system design and operation is discussed in UFSAR Section 9.6.2.CCW system design and operation is discussed in UFSAR Section 9.3.6.0 Environmental ConsiderationThere are no changes to the plant discharge temperature limits as specified in the Turkey Pointdischarge permit in response to an increase in maximum intake temperature limit to 1040F. Plantdischarge limits are a function of the quantity of heat rejected to the canal system during plantoperation and are not intake temperature limited.10 CFR 51.22(c) provides criteria for, and identification of, licensing and regulatory actionseligible for categorical exclusion from performing an environmental assessment. 10 CFR51.22 (c)(9) identifies a proposed amendment to an operating license for a facility as acategorical exclusion not requiring an environmental assessment or environmental impactstatement if operation of the facility, in accordance with the proposed amendment, would notinvolve: (i) a significant hazards consideration; (ii) a significant change in the types or significantincrease in the amounts of any effluent that may be released offsite; or, (iii) a significant increasein individual or cumulative occupational radiation exposure.FPL has reviewed the proposed license amendment and concludes that it meets the eligibilitycriteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). The following is the basis forthis determination.i. The proposed license amendment does not involve a significant hazards consideration asdescribed previously in the No Significant Hazards Consideration Evaluation in Section5.1 above.ii. The proposed change is to increase the temperature limit for the UHS. The proposedchange will not result in a significant increase in radiological doses for any design basis L-2014-216EnclosurePage 17 of 17accident as discussed in Sections 4.1.1 and 4.1.2 above. The proposed change does notresult in a significant change in the types or significant increase in the amounts ofeffluents that may be released offsite. There will be a slight increase in the temperatureof the plant cooling water effluent, but the effect is small and manageable, has no effecton radiological releases, and the effluent is limited by the plant discharge permit.Therefore, there will not be a significant increase in the types or amounts of effluents thatmay be released offsite.iii. The increased cooling water inlet temperature that would be allowed under the proposedchanges will not result in any increase in individual or cumulative occupational radiationexposure.Accordingly, the proposed amendment meets the eligibility criteria for categorical exclusion setforth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impactstatement or environmental assessment need be prepared in connection with the proposedamendment.7.0 ConclusionsBased on the review of the Turkey Point Units 3 and 4 design bases and supporting technicalevaluations, it has been determined that the proposed TS change will not adversely affect plantoperation, jeopardize the performance of safety related equipment, or otherwise compromisepublic health and safety. Therefore, the proposed change to TS 3/4.7.4, which increases themaximum measured UHS temperature from 100&deg;F to 104'F, is justified.8.0 PrecedentMillstone Power Station Unit No.2, Amendment No. 318 dated April 18, 2014 (TAC No.MF1779)9.0 AttachmentAttachment -Proposed Technical Specification Page 3/4 7-17 Mark-up AttachmentProposed Technical Specification ChangesPage 3/4 7-17 Mark-Up PLANT SYSTEMS3/4.7.4 ULTIMATE HEAT SINKLIMITING CONDITION FOR OPERATION3.7.4 The ultimate heat sink shall be OPERABLE with an average supply water temperature less than or equal toAPPLICABILITY: MODES 1. 2, 3. and 4.ACTION:With the requirements of the above specification not satisfied, be in at least HOT STANDBY within 12 hours and4n COLD SHUTDOWN within the following 30 hours. This ACTION shall be applicable to both unitssimultaneously.ISURVEILLANCE REQUIREMENTS4.7.4 The ultimate heat sink shall be determined supply-,watf te.pefe.. Fe. t. be within. its limil.it ioac~t onto nor ~1 flourt tv vorIt'.lna tflo avornanII--Ij b. Verify average supply water temperature* to be within the limit at least once per 6ja. At least once per 24 hours by verifying the average-within its limit.supply water temperature* to be<-b. Verify average supply water temperature* to be within the limit at least once per 6hours when water temperature exceeds 100TF.*Portable monitors may be used to measure the temperature.TURKEY POINT -UNITS 3 & 43/4 7-17AMENDMENT NOS. 260 AND 2-9 I}}

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