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#REDIRECT [[SBK-L-15132, Response to Request for Additional Information for License Amendment Request 14-04 Revised Reactor Coolant System Pressure - Temperature Limits Applicable for 55 Effective Full Power Years]]
| number = ML15194A042
| issue date = 07/09/2015
| title = Seabrook Station - Response to Request for Additional Information for License Amendment Request 14-04 Revised Reactor Coolant System Pressure - Temperature Limits Applicable for 55 Effective Full Power Years
| author name = Dodds R A
| author affiliation = NextEra Energy Seabrook, LLC
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000443
| license number =
| contact person =
| case reference number = SBK-L-15132
| document type = Letter, Response to Request for Additional Information (RAI)
| page count = 15
}}
 
=Text=
{{#Wiki_filter:N ExTeraENERGY !,,.,-ýSEýAB ROýOKJuly 9, 201510 CFR 50.90SBK-L-15132 Docket No. 5 0-443U. S. Nuclear Regulatory Commission Attn: Document Control DeskWashington, DC 20555-0001 Seabrook StationResponse to Request for Additional Information for License Amendment Request 14-04Revised Reactor Coolant System Pressure
-Temperature Limits Applicable for 55 Effective Full Power Years
 
==References:==
: 1. Seabrook Station License Amendment Request 14-04, "Revised Reactor Coolant SystemPressure
-Temperature Limits Applicable for 55 Effective Full Power Years," SBK-L-14102, July 24, 2014 (ML14216A404).
: 2. NRC letter to Seabrook
: Station, "Seabrook
: Station, Unit No. 1 -Request for Additional Information Regarding License Amendment Request to Revise the Technical Specification Pressure-Temperature Limits and Request for Exemption from 10 CFR Part50, Appendix G Minimum Temperature requirements (TAC Nos. MF4576 andMF4577),"
dated January 9, 2015 (ML14363A367).
: 3. Seabrook Station letter SBK-L-15040, "Response to Request for Additional Information for License Amendment Request 14-04 Revised Reactor Coolant System Pressure
-Temperature Limits Applicable for 55 Effective Full Power Years, dated March 9, 2015(ML15072A036).
: 4. Seabrook Station letter SBK-L-15129, "Response to Request for Additional Information for License Amendment Request 14-04 Revised Reactor Coolant System Pressure  
-Temperature Limits Applicable for 55 Effective Full Power Years, dated June 23, 2015.In Reference 1, NextEra Energy Seabrook, LLC (NextEra) submitted License Amendment Request (LAR) 14-04 to the Technical Specifications (TS) for Seabrook Station and requested anexemption from the requirements of 10 CFR 50 Appendix G. The proposed change revises theNextEra Energy Seabrook, LLC, P.O. Box 300, Lafayette Road, Seabrook, NH 03874 U.S. Nuclear Regulatory Commission SBK-L- 15132/Page 2pressure-temperature (P/T) limits in TS 3 /4.4.9 LCO 3.4.9.1, Reactor Coolant System Pressure-Temperature Limits, to be applicable to 55 effective full power years. The change also revisesTS 3 /4/4.9 LCO 3.4.9.3, Overpressure Protection
: Systems, by providing new overpressure protection setpoints and lowering the RCS temperature at which the TS is applicable.
In Reference 2, the NRC requested additional information to complete its review of LAR 14-04.NextEra provided the responses to RAIs 2.1.1, 2.1.2, 2.1.3 and 2.1.4 in Reference 3 along with arequest to extend its response to RAI 2.2.1 to June 30, 2015.The response to RAI 2.2.1 required additional input from the vendor to complete the response.
In a conference call on June 17, 2015, the NRC requested an additional note be added to theSeabrook pressure-temperature curves restricting the heat-up rate to less than or equal to 20 'Fper hour for moderator temperatures less than 120 'F. In Reference 4, NextEra requested additional time to obtain the requested information from its vendor, Westinghouse and to submitits response to RAI 2.2.1.The response to RAI 2.2.1 is provided in the enclosure to this letter. The revised marked-up technical specification pages are provided in the attachment to this letter.The response to the NRC RAI-2.2-1 resulted in a change to the previously submitted LicenseAmendment Request 14-04 for the Seabrook Technical Specification (TS) 3.4.9.1, Pressure
/Temperature Limits, by providing new reactor coolant system (RCS) pressure and temperature (P/T) limits that are applicable to 55 effective full power years (EFPY). As a result, a NoSignificant Hazards Consideration was performed for the revised Pressure Temperature Limits inTS Figures 3.4-2 and 3.4-3.This letter contains no regulatory commitments.
Should you have any questions regarding this letter, please contact Mr. Michael Ossing,Licensing
: Manager, at (603) 773-7512.
I declare under penalty of perjury that the foregoing is true and correct.Executed on July _\ ,2015.Sincerely, NextEra Energy Seabrook, LLCRalph A. Dodds, IIIPlant General ManagerEnclosure U.S. Nuclear Regulatory Commission SBK-L-15132/Page 3cc: D. Dorman, NRC Region I Administrator J. Lamb, NRC Project Manager, Project Directorate 1-2P. Cataldo, NRC Senior Resident Inspector Mr. Perry PlummerDirector Homeland Security and Emergency Management New Hampshire Department of SafetyDivision of Homeland Security and Emergency Management Bureau of Emergency Management 33 Hazen DriveConcord, NH 03305John Giarrusso, Jr., Nuclear Preparedness ManagerThe Commonwealth of Massachusetts Emergency Management Agency400 Worcester RoadFramingham, MA 01702-5399 ENCLOSURE to SBK-L-15132 Response to Request for Additional Information for License Amendment Request 14-04Revised Reactor Coolant System Pressure
-Temperature Limits Applicable for 55 Effective Full Power Years Response to Request for Additional Information for License Amendment Request 14-04Revised Reactor Coolant System Pressure
-Temperature Limits Applicable for 55 Effective Full Power YearsNRC RAI2.2.1.:
The current TS P-T limit curves for 23. 7 EFPY have margins to account for pressureand temperature instrument errors; the proposed 55 EFPY TS P-T limits do not have these margins.Please address how instrumentation errors will be accounted for to ensure that the RCS is operated inaccordance with the proposed TS P-T limits for 55 EFPYNextEra Response:
The proposed TS P-T limit curves for 55 EFPY have been revised to include margins to account forpressure and temperature instrument uncertainty.
Changes were also made to eliminate heat up and cooldown rates that are not achievable during normal plant operating conditions in the lower temperature regions where the cold overpressure mitigation system (COMS) is enabled to protect the RCS withpower operated relief valves (PORVs) as identified in TS Figure 3.4-4. No changes were made to thePORV set point values TS Figure 3.4-4 as this figure already contains appropriate instrument uncertainty as well as additional margins for pressure overshoot transients should an actuation occur.Specifically, the revised curves shift the heat up and cool down P-T Limits curve data points developed in WCAP-17441-NP by 100 psi downward and 20'F to the right to account for the instrument uncertainty.
An additional 15 psi uncertainty was applied to the heat up curve above the COMS enabletemperature where operationally the wide range pressure indication on the main control board could bethe only available indication in some unlikely but possible scenarios.
In addition to accounting for instrument uncertainty, unachievable heat up and cool down rates wereeliminated or restricted.
For the heat up limitation curve, proposed TS Figure 3.4-2, a heat up rate restriction of 20°F/hr wasadded at temperatures at or below 120'F, corresponding to the transient defined in WCAP-17444 andthe previous response to RAI 2.1.4. At temperatures greater than 120'F to less than 200'F the heat uprate of 80°F/hr maximum is specified and at greater than or equal to 200'F the maximum rate is100°F/hr.
Instrument uncertainties of 20'F and 100 psi were added to the data points in WCAP-17441-NP Table 6-3. An additional pressure uncertainty of 15 psi was added to the heat up curve starting at200'F prior to the cold overpressure mitigation system being disabled.
Considering the 20°F/hr raterestriction, pressure and temperature data from 60'F to 80'F (40°F to 60'F without the instrument uncertainty of 20'F) were determined using the more limiting pressure rate change between the existing80°F/hr heat up data and the steady state data. Linear extrapolation of the 60'F to 65°F allowable pressure change of 13 psi per 5°F was applied to the heat up curve pressure limits from 60°F to 80'F.These heat up rate limitations and instrument uncertainties additions result in all pressure limitations ator below 225°F, in the COMS enable temperature region, being above and protected by the COMSsystem set point curve in TS Figure 3.4-4.For the cool down limitation curve, proposed TS Figure 3.4-3, the cool down rate is restricted to 20°F/hrat temperatures less than 150'F. Instrument uncertainties of 20'F and 100 psi were added to the datapoints in WCAP-17441-NP Table 6-4. Since the entire curve is to the left and above the COMS enabletemperature and pressure limits identified in TS Figure 3.4-4, the additional 15 psi uncertainty was notPage 1 of 6 necessary.
Pressure and temperature data from 60'F to 80'F (40'F to 60'F without the instrument uncertainty of 20'F) were determined by linear extrapolation of the pressure rate change between 60'Fto 65'F for the 20°F/hr cool down data and the steady state data which results in a 13 psi change per5°F. These cool down rate limitations and instrument uncertainties additions result in all pressurelimitations being above and protected by the COMS system set point curve in TS Figure 3.4-4.The bolt up temperature was maintained at 60'F as identified in WCAP-14040-A, Revision 4,"Methodology Used to Develop Cold Overpressure Mitigating System Setpoints and RCS Heatup andCooldown Limit Curves."
The limiting closure head region material RTndt is 30°F allowing bolt uptemperature to be as low as 50'F with the application of uncertainty.
: However, the 60'F bolt uptemperature advised in WCAP-14040-A is maintained.
The proposed heat up limitation curve, TS Figure 3.4-2, and the proposed cool down limitation curve,TS Figure 3.4-3 applicable for 55 EFPY have been revised to include margins to account for pressureand temperature instrument uncertainty as described above and are provided in the attachment.
Therevised data points for the revised heat up and cool down curves are provided in Tables 1 and 2respectively.
Page 2 of 6 Significant Hazards Consideration No Significant Hazards Consideration:
The response to the NRC RAI-2.2-1 resulted in a change to the previously submitted LicenseAmendment Request 14-04 for the Seabrook Technical Specification (TS) 3.4.9.1, Pressure
/Temperature Limits, by providing new reactor coolant system (RCS) pressure and temperature (P/T)limits that are applicable to 55 effective full power years (EFPY). As a result, a No Significant HazardsConsideration was performed for the revised Pressure Temperature Limits in TS Figures 3.4-2 and 3.4-3.In accordance with 10 CFR 50.92, NextEra Energy Seabrook has concluded that the proposed changedoes not involve a significant hazards consideration (SHC). The basis for the conclusion that theproposed change does not involve a SHC is as follows:1. Does the proposed change involve a significant increase in the probability or consequences of anaccident previously evaluated?
No. The proposed changes to the Technical Specifications (TS) do not impact the physical function ofplant structures,
: systems, or components (SSCs) or the manner in which SSCs perform their designfunction.
Operation in accordance with the proposed TS will ensure that all analyzed accidents willcontinue to be mitigated by the SSCs as previously analyzed.
The proposed changes do not alter orprevent the ability of operable SSCs to perform their intended function to mitigate the consequences ofan initiating event within assumed acceptance limits. The proposed changes neither adversely affectaccident initiators or precursors, nor alter design assumptions.
Therefore, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.
: 2. Does the proposed change create the possibility of a new or different kind of accident from anypreviously evaluated?
No. The proposed changes do not involve installation of new or different type of equipment, create newfailure modes for existing equipment, or create any new limiting single failures.
The changes to thepressure
-temperature limits will continue to ensure that appropriate fracture toughness margins aremaintained to protect against reactor vessel failure, during both normal and low temperature operation.
The proposed changes are consistent with the applicable NRC approved methodologies (i.e., WCAP-14040, Rev. 4 and ASME Code Case N-641). Plant operation will not be altered, and all safety functions will continue to perform as previously assumed in accident analyses.
Therefore, the proposed changes do not create the possibility of a new or different kind of accident fromany accident previously evaluated.
Page 3 of 6
: 3. Does the proposed change involve a significant reduction in the margin of safety?No. Margin of safety is associated with confidence in the ability of the fission product barriers (i.e., fuelcladding, reactor coolant system pressure
: boundary, and containment structure) to limit the level ofradiation dose to the public. The proposed changes will not adversely affect the operation of plantequipment or the function of any equipment assumed in the accident analysis.
The proposed changeswere developed using NRC approved methodologies and will continue to ensure an acceptable marginof safety is maintained.
The safety analysis acceptance criteria are not affected by this change. Theproposed changes will not result in plant operation in a configuration outside the design basis. Theproposed changes do not adversely affect systems that respond to safely shutdown the plant and tomaintain the plant in a safe shutdown condition.
Therefore, the proposed changes do not involve a significant reduction in a margin of safety.Based on the above, NextEra concludes that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(b),
and, accordingly, a finding of"no significant hazards consideration" is justified.
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{Aj Fc aq oj sju!od mujI alqui Table 2Data Points for the 55 EFPY Seabrook Unit 1 Cooldown Curves using the 1998 through the 2000 AddendaApp. G Methodology (with Kic, without Flange Notch, and with Margins for Instrumentation Errors)Steady-State 201F/hr Cooldown 100°F/hr Cooldown(00F/hr)T P P P(OF) (psig) T (0F) (psig) T (0F) (psig)60 0 60 060 577 60 53765 590 65 55070 603 70 56375 616 75 57680 629 80 58985 642 85 60290 656 90 61895 671 95 635100 689 100 654105 708 105 674110 729 110 697115 752 115 723120 778 120 751125 806 125 782130 838 130 817135 872 135 855140 911 140 897145 953 145 944150 1000 150 995 150 995155 1052 155 1052160 1109 160 1109165 1172 165 1172170 1242 170 1242175 1319 175 1319180 1404 180 1404185 1499 185 1499190 1603 190 1603195 1718 195 1718200 1846 200 1846205 1986 205 1986210 2142 210 2142215 2314 215 2314220 2504 1 220 2504Page 6 of 6 Attachment to SBK-L- 15132Marked-Up Technical Specification Pages 11v!SeRT-A (A/X 7 itCL --- L 1 --I- J , -I-.. T-r ---.--1 TL ----iea estI I I I I I I I iILinaccepta
' ''ceptable S Operati T,, .operation
-Hea Rate [ ticaI irnit80 Deg. F/Hr 1 0DegF~r.L+/-.
I IL.J, L.S Heatu I I I I I Ia Imit I I100 g. F/ -r ----i- -'-- --- " -FR-rIL AI II I iiIIi I I Ii tr I --I--I4 -I eP 4I-t I l tI l i-I- T -T 1-----Z --...1000 -/" A/ii._.IlO00I,300IRE (Deg. F, gI8500UP 0 23.7 EFPY/O /E tFESEABROOK
-UNIT 13/4 4-23SEABROK -UNIT 3/44-23Amendment No. 19, 89, 115,13-5 Insert AMATERIAL PROPERTY BASISLIMITING MATERIAL:
Lower Shell Plate RI 808-1 without using surveillance data, Position 1.1LIMITING ART VALUES AT 55 EFPY: 1/4T, 117°F (Axial Flaw)3/4T, 105'F (Axial Flaw)Curves applicable for the first 55 EFPY and contain margins for possible instrument errors25002250 _ _ ILeak Test Limit 2000 -_ _1750 "170Critical LimitIHeatup Curve-- 1500Unacceptable IOperation ICLIa
_ 1250 .---p,U)Heatup rate belowrn- 1000 --120 F shall not -- , _-_ exceed 20OF/hr -Composite Heatup Curve750 Indicated RCS Maximum Alloy(fl Temperature Heatup RatT5 <120&deg;F 20F/hrO ------ 200'F > T > 120&deg;F 80&deg;F/hr'5025000 50 100 150200 250 300 350 400 450 500 550RCS Temperature (Deg. F, 10 Deg. F per division)
* Curve is Applicable for RCS Vacuum fillFIGURE 3.4-2REACTOR COOLANT SYSTEM HEATUP LIMITATIONS
-APPLICABLE UP TO 55 EFPY 1,4,YW re(x-r F A, ejV1AERIAL PR ERTY BASISLimiting erial: LOWER 5 ELL P/LATE -,1808-1ART values a 3.7 EFPYI/4 , 109'F4T, 880PCurves appli lr the firs EFFY and ntain margin 20'F and 100 ig for possib instrument error-,onon --"-./ //802600 -24002200 -20001800 -wILS160CD* 1400-CO)120S1000-0-600200-r 1 -- -------1. -1'3rT- -''r- -------I/ I I I I .ptableII IIII peration
--j.4 .L __- -_ -J ------- ------- ----------
--I-------,
----Co -ldown taUplo g I I I-- ---I ,-----------
--r--iI I I I ----
-- '---, -I--P- --II I I I ----- --iI I I l t-l ...I -T r 7-- Cool n Rates t L ~ f...A L....L.i
-....c Deg.F/Hr
-, 2 I I I I I I I I I I-e. -,- -- ----- -- -----4.JWLJ. 80, 100 D .F/hr JIIAI JI -LJ L -..h-I-I I I I I I I I I I I I I I&#xa3; _ I &#xa3; I I! _ I I I I i I i J 'I I I IB I pI I I I II I I I I I I I I I I I I I I I I I II I I I I I I I I I I I I II I I I I I II I I II I I I I I I I Im pI I I I I I I I I II I I I III I I I I I I I II 1 I I//11/, 7''10 100 200 300 400 500R TEMPERAT (Deg. F, 2 eg. F PER DV ION)GURE 3.4-3ACTOR COO T SYSTEM OLDOWN LI11 ATIONS -LICABLE UP 23.7 EF YSEABROOK
-UNIT 13/4 4-24Amendment No. 19, 89, 115, 135 Insert BMATERIAL PROPERTY BASISLIMITING MATERIAL:
Lower Shell Plate RI 808-1 without using surveillance data, Position 1.1LIMITING ART VALUES AT 55 EFPY: 1/4T, 1177F (Axial Flaw)3/4T, 1057F (Axial Flaw)Curves applicable for the first 55 EFPY and contain margins for possible instrument errors2500225020001750C0> 1500CL0)0 1250CL0Lo)10007505)C,)W~ 500F neptableLgperaionj Li..AcetableI ItF--Composite Cooldown CurveIndicated RCS Maximum Allowable Temperature Cooldown RateT < 150&deg;F 20&deg;F/hrT > 150&deg;F 100&deg;F/hr2500I ..I ....I ....I .. ..0 50100 150 200 250 300 350 400 450500550RCS Temperature (Deg. F, 10 Deg. F per division)
* Curve is Applicable for RCS Vacuum fillFIGURE 3.4-3REACTOR COOLANT SYSTEM COOLDOWN LIMITATIONS
-APPLICABLE UP TO 55 EFPY}}

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