ML20082E432

Proposed Tech Specs,Relocating Overtemp & Overpower Delta Temp Equation Constants to COLR

ML20082E432
Person / Time
Site:	Sequoyah
Issue date:	04/06/1995
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20082E409	List: ML20082E401 ML20082E432
References
NUDOCS 9504110225
Download: ML20082E432 (17)

Text

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" ENCLOSURE 1'

~ PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE ,

SEQUOYAH NUCLEAR PLANT (SON) UNITS 1 AND 2 d DOCKET NOS. 50-327 AND 50-328

~

(TVA-SON-TS-95-11) >

LIST OF AFFECTED PAGES -

Unit 1 2-7 -

2-8 2-9 2-10 .

6-21 Unit 2 2 2-10 2-11 6-22 t

e. i PDR DO PDR

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gg >,t-:

u,- -

TABLE 2.2-1 (Continued)

-E 8

[6 ,

REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS '

' FUNCTIONAL UNIT . TRIP SETPOINT ALLOWABLE VALUES = ..-

• E 21. Turbine Impulse Chamber Pressure -- -

< 10% Turbine Impulse R145

.Z (P-13) Input to Low Power Reactor Trips

< 12.4% Turbine Impulse:

Fressure Equivalent

. _ g- Block P-7 Fressure Equivalent.?

22. Power Range Neutron Flux - (P-8) Low < 35% of RATED - < 37.4% of RATED-'

Reactor Coolant Loop Flow, and Reactor . THERMAL. POWER LR145h THERMAL POWER Trip

23. Power Range-Neutron Flux - (P-10) - > 10% of RATED

> 7.6% of RATED Enable Block of Source, Intennediate, THERMAL. POWER THERMAL POWER and Power Range (low setpoint) Reactor j Trips Reactor. Trip P-4

} 24. ~

Not Applicable N6t Applicable

~ 25. Power Range Neutron Flux - (P-9) - <: 50% of. RATED < 52.4% of RATEDL Glocks-Reactor Trip for. Turbine THERMAL POWER THERMAL POWER Trip Below 50% Rated Power g

-NOTATION

( q, 3

-NOTE 1: Overtemperature af ( I 4$) AT,(Kg -K S

I )[ T'] + K (P-P') , fy(AI)}

3 2 (11 +2 t S gy 1+tS5 R14b .'

' ~

I Where: 4- = Lead-lag compensator on measured AT

+

?{# A * *5S

=.Time constants utilized i htg. & )fs })eesExmr0 TA' YA C yE I 4,TS. CORE OWMC l Yl/ W . . lead-lag controller for AT,:A '- 12 x ;, ;W - 3 :::.

.$g

- AT, = Indicated AT at' RATED THERMAL POWER ^

-~

-933; WT9,rgn7pAE AT fokrox Tr>P ISTft/Mr f kmhDc7

2 coa tw7ws Lixins RfbKr. , , ,,, gg,y fggyy,ggry Y

2 p h ge C6 OfD64T/Y lh6W AME ~

24 T w g)3 _llyn;" L' % ,,,,,,,, w Q "

=w -~ .

y, -

E TABLE 2.2-1 (Continued)

8' -

Y REACTOR TRIP SYSTEM 1NSTRUMENTATION TRIP SETPOINTS NOTATION (Continued) ~ '

. "E NOTE 1: (Continued) *

-i g 1+rSy

=

1+rS2 The v- function generated by the lead-lag controller for T, dynamic compensation V R145-r,&r y =

Time constants utilized in the lead-lag controller for T

~

As RefsEn!TED IdTHE 2 avg * :1 1

2

=*a s. COfE OPER. Ftir 0 Cr LiltllTS REPORT. 2 ::::.y T = Average temperature *F

> R145 T' < 578.2*F (Nominal T at RATED THERMAL POWER)

"y, )

K 3

^ ^^^~ CrcrnWEM 6 E lGML E NMMIWIN (gjg' 7(dwrAs fersovisp Iv7xt CofE OfMAT/A6 UM/TS AE/O' Al-

}

_.e, M N A  %

P' =

2235 psig (Nominal RCS operating pressure)

S = Laplace transform eperator (sec-1) and fy(AI) is a function of the indicated-difference between top and bottom detectors; of the power-range nuclear ion chambers; with gains to be selected based on measured instrument response during plant startup tests such that:

(i) for q ~9 b between - 29 percent and + 5 percent fy (AI) = 0 (where qt and g t b 3g- y are percent RATED THERMAL POWER in the top and bottom halves of the core respectively, kkg

"" U

.hx -

5 = Lnc COMPERLSA70A 0N # #S TA!02 (

R ~_o y ,,u 4 rs ,;ie masa a 7,a Lss 0om^ws"'S A' T7 =  !""' 0"#

" Bee.scwoLa!, Tor CalE ~ Ol'EAAM IJ/M'M N##

O x_ y_ b K N

__ _ -__ =

~- . E:

.. . z . .

v, TABLE 2.2-1 (Continued) ,

m '

$ REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS

%

• NOTATION (Continued) .

E . NOTE 1: (Continued) g (ii) for each percent that the magnitude of (qt ~ 9 b) exceeds -29 percent, the AT trip set -

point shall be automatically reduced by 1.50 percent of its value at RATED THERMAL- POWER.

R23 (iii) for each percent that the magnitude of (qt A ) exceeds +5 percent, the AT. trip set-b point shall be automatically reduced by 0.86 percent of its value at RATED THERMAL POWER.

^ ~ ~ ^

xS 15 NOTE 2: Overpower AT ( 4 < AT, {K4 -K 3 ) T - K6(T-T") - f 2(OI)}

i

-1+1 5 5 (1 + T3 5 m 1 1 3

= 1*'q 5 _f.+ ti S al45 Where:

1+r54 = as defined in Note 1 1+T55 T4 ,t5 = as defined in Note 1 AT,

= as defined in' Note 1 N R118 N 9 ' ^^' OvsePom' AT RmooR.TA.lP SETPof4T MS [fE5Eg7FO K

4 ' yjj[' 'CogE OMRA7wG LM/TS NW .

}

Pg K = 0.02/ f for increasing aver- :  ;;

t;;,peraturcand0f;-d::reasing;;Y fL /$ E Y $khb5?$Y. As es$ se Y YGIA N .

T3 3 = The function generated by the rate-lag controller for T,yg dynamic R145 g 1,73 -

• 3 compensation U

1

=

% 9 T .c, i

AsfDEFINEO E -

q, = As btTintD 3 M

. _ _ _ _ _ - _ . _ = _ D~

m.

vv

~.

m 4/sj TABLE 2.2-1 (Continued)

~

(

w g REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS E

g . NOTATION (Continued)~ .- -

r

' NOTE 2: (Continued E .sts /kE56207Ep '

q I = Time constant utilized in the rate-la controller for T-avg, - IC ::::. R145-3 27~ 3

, IA R c CORE OPERATMiG l_/M/73 K = T" ::,2 Y -Ci Craef'otJex ET fencroz Top Acamp :

6 C.CC11

_S,7,ym 7i;;g,T :

ogyy pog,,g,Q ',T" pg;g:,Tgg7y7y3,3,,(ggg gpyy97wg Dm n frygg T = as'aen n

~ -

T" = at RATED THERMAL POWER.(Calibration temperature for ~ 1 Indicated T,yg AT instrumentation, < 578.2 F) as defined in Note 1 S =

f2 (aI) 0 for all AI E l iOTE 3: The channel's maximum trip setpoint shall not exceed its computed trip point by'more than 1.9 percent AT span.

NCTE 4: The channel's maximum trip setpoint shall not exceed its computed trip point by more than R145' 1.7 percent AT spa g _

1-wg 1 A3 bcrnuen L IVovt 1, F$a .i.+'t,S

=

(z g = As berw ro L MOTE I .

\ -

b w

o ..

ADMINISTRATIVE CONTROLS H0kTHLY REACTOR OPERATING REPORT 6.9.1.10 Routine reports of operating statistics and shutdown experience, including documentation of all challenges to the PORVs or Safety Valves, shall be submitted on a R76 monthly basis no later than the 15th of each month following the calendar month covered by the report.

CORE OPERATING LIMITS RFPORT 6.9.1.14 Core operating limits shall be established and documented in the CORE OPERATING LIMITS REPORT before each reload cycle or any remaining part of a reload cycle for the following:

1. Moderator Temperature Coefficient BOL and EOL limits and 300 ppm surveillance limit for Specification 3/4.1.1.3, R159

2. Shutdown Bank Insertion Limit for Specification 3/4.1.3.5,

3. Control Bank Insertion Limits for Specification 3/4.1.3.6,

4. Axial Flux Difference Limits for Specification 3/4.2.1,

5. Heat Flux Hot Channel Factor, K(z), and W(z) for Specification 3/4.2.2, and

6. Nucl r En wer Fac

7. One.TtnetgAmec Ano C$ccoutR DELTU 5eTroirJrIiwAmnr2 bcs k SPEClPlc677ed 221-

. . .a.a one analymal iiietiicd5 #ed w dfEe7mirre'ThT$re opeRtN those previously reviewed and approved by NRC in:

1. WCAP 9272 P A " WESTINGHOUSE RELOAD SAFETY EVALUATION HETHODOLOGY", July 1985 (H Proprietary).

(Methodology for Specifications 3.1.1.3 Moderator Temperature Coefficient, 3.1.3.5 Shutdown Bank Insertion Limit. 3.1.3.6 -Control Bank Insertion Limits, 3.2.1 - Axial Flux Difference, 3.2.2 - Heat Flux Hot Channel Factor, and 3.2.3 Nuclear Enthalpy Hot Channel Factor.)

2. WCAP 10216 P A, " RELAXATION OF CONSTANT AXIAL OFFSET CONTROL F SURVEILLANCE a

TECHNICAL SPECIFICATION". JUNE 1983 (W Proprietary).

(Hethodology for Specification 3.2.1 Axial Flux Difference (Relaxed Axial Offset Control) and 3.2.2 Heat Flux Hot Channel Factor (W(z) surveillance requirements for FoMethodology).)

3. WCAP 10266 P-A Rev. 2. "THE 1981 REVISION OF WESTINGHOUSE EVALUATION H0 DEL USING BASH CODE", March 1987, (W Proprietary).

(Hethodology for Specification 3.2.2 Heat Flux Hot Channel Factor).

l 4. WCAP 13631 P A, " SAFETY EVALUATION SUPPORTING A HORE NECATIVE E0L H0DERATOR TEMPERATURE COEFFICIENT TECHNICAL SPECIFICATION FOR THE SEQUOYAH NUCLEAR R175 PLANTS " HARCH 1993 (W Proprietary).

(Het g gti 6 or Tamneratur 5, went- 876- H, "DEstw Mses FOA 'M Tm/A.

OYER PCu)E7e AT fluo THE7/??AL OVERTD7/WAATl/Af l AT T/!? FwucTices ) SEPTorM ER I Ub l M Pwnenj).

(tritTH0botoGy & Spectnca rioN 2.2.1 - Sonor Txit Sys7a1 .TNinewr/Dv7?fMAJ SE7tD/4/73) r j SEQUOYAH - UNIT 1 64 Nos. 52, 58. 72, 74, I October 26, 1993 117, 152, 155,  !

156, 171 1

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nig

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= LacJ Com ptrasnToAL 00' Mmsut# At -

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.qb .-

• Time Coasrar Uriuzco In Tae LAs (osAnvs& Fetinrl5Assatirevk '

• 6/ERM7743 up/7s? /Ota62; '

g ABLE 2.2-1 (Continue ,

o /; .

8 [

-REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS -

5 x ... ,

NOTATION g l \ /1 N-q A* ti,s) \1 S)

N S ~

NOTE 1: OvertemperatureAT(1+TS)[5AT,{K 4 ~E R132i 1+T55 1 2 (1 +2 T 5* I )[T'-3 T'] + K y(P-P') - f (AI)]:

1+TS4 Len o- -

4 where:

1 * '55

'

• As AssanEn1;r DE -  !

T4.T5 = Time0;constants utilized in the-lead-lag controller for AT' - ' ----

& '5 E 0lWNS AIA'* SEW AT, = Indicated AT at. RATED THERMAL POWER _

R21^

K 5 1.1E OyexTevMAA7/12c Ar b e w x Txit Ser/Di<!r-AsAas*7En M^<cv l 1

CORE O POLATIMG Lim lT.s Rma.

Kg = OrOH Oreg7Dr/PERAYMEC' AT AE79 cut TL/P licM77tf AETRAIT*-&LY WFRCIEWi~ l AG OD*/PElllSA7eA ON /demexED AT 1+TS. y

.1+T32 = The function generated by the lead-lag controller for T,yg' dynamic' compensation R1321 T

14T2= Time constants utilized COE Oin the lead-la controll r for Tag 1

- - W g - -

2

C 7//E /N6 / / dE e

eg T

= Average temperature 'F --

-4 i 578.2*F (Nominal T,yg at RATED THERMAL POWER)

• * * > ~

K

= "fc.::::S OrterotkRriner AT fEMTot Tx!!'

{0$[Dttgrs.sunszATier/

OfDC87YO U/1llU $ ~SE7NM!r 3

[-n iuszy CCEFF/C/EWr $$ krsCCMD .TNDE jo - P- = Pressurizer pressure, psig a g . P_ ' = 2235 psig (Nominal RCS operating pressure)-

1 C

~

' KS g

. = LMG CcisrMNS$70A

=

Om /!kM9/ RED Tos.

ri,,c coon, ariueco rowmsaso va furtwscoxA A

c

' Brestw7En .51'771e; CDRE C/EXAT/41G L/M/TS7/EMA7~I ,

. .- - - _ _.__ _ _ = n -. m: - . :2 . ..

.2 .. -

, TABLE 2.2-1 (Continued) -

m .

$ REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS 5

x: .-

e

-NOTATION (Continued)

E C

NOTE 1: (Continued) -

S = Laplace transform operator. sec-I' and fy(AI) is a function of the indicated difference between top and bottom detectors of the power-range nuclear ion chambers; with gains to be selected based on measured instrument response during plant startup tests such that:

, (1) for qt ~9b between - 29 percent and + 5 percent yf (AI) = 0 (where qt and qb O are percent RATED THERMAL POWER in the top and bottom halves of the core respectively. R21 and qt

• 9b is total THERMAL POWER in percent of RATED THERMAL POWER).

(ii) for each percent that the magnitude of (qt " 9 b) exceeds -29' percent, the AT trip set-point shall be automatically reduced by 1.50 percent of its value at RATED THERMAL POWER.

(iii) for each percent that the magnitude of (qt 9b) exceeds +5 percent, the AT trip set-j point shall be automatically reduced by 0.86 percent of its value at RATED THERMAL POWER.

~

f3) {L L (1+t35) \1+t7 5 (1+Y

\ 7 5-NOTE 2: Overpower AT (1 + 'T4 5) 5 AT,{K4 -K 3 ) T -K6 U - T9.-- f p(AI)}

O c3 mE 1+rS5 5 (1 + t3 S R132 H5 1+t t

1 t--s I

where: = as defined in Note 1 1+185

~~I l3 o-

• ) s.,

N

f,,

e':

4

'.._ l m TABLE 2.2-1 (Continued)-

E '

g REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS '

NOTATION (Continued)

$ As bCFH0E0 Te) 10cTE i

• 3 :

[ , As bEFDOED L NOTE i NOTE 2: (Continued)

= as' defined in Note 1 R132 AT = as defined in Note 1 Y 'y^}^kOVW M # bC# '

K 4 --

ogging um>73 A'EPORT~.

K 0

= 0.02/"I f:r intr:::ing O'; r:;: t:rg:r:ter: :nd 9 fer d::re::in; : re; t;;p r:ter: OscR/%kne AT Rencror The &nvdr Avnay (CErric/Ewr RA Cer1MEIa Tgn. , As Pxesswrro h De C62E OPERRMS IJ/U/7S KPDS N IS 32 1+tS= 3 The function generated by the rate-lag controller for T,yg dynamic compensation _

= Time cons nt As /kEsEW7ED t lized in the rat a ontroller for T 3 3 TWE C E _

TNG /Jnl/75 .

av9,3 - 10 ::::.

K 6 = 10 i or T : T" and K - O fer T < 7" Orgp/m/e;E ATfofCTdeTe///YX71/P g Serna lhnL7y lotFFlubir As PRESEE7zz)kTat (Ge[ OMRffM/S JJMJ73 87df 321 g 'T = as defined in Note 1 a

O Po T"' = Indicated Tavg at RATED THERMAL-POWER (Calibration temperature for o P.

H z AT instrumentation, < 578.2*F) c.,. *

...,,y S = as defined in Note'l i

~

j y f 2(AI) = 0 for all AI j a2 l

, 4 t1

=

=-

ns - 1~ ~ 1 As bErmen L NoTr 1. '

}

~ ~ _ -

O ADMINISTRATIVE CONTROLS HONTHLY ' REACTOR OPERATING REPORT 6.9.1.10 Routine reports of operating statistics and shutdown experience, including R64 documentation of all challenges to the PORVs or Safety Valves, shall be submitted on a monthly basis no later than the 15th of each month follnwing the calendar month covered by the report.

CORE OPERATING LIMITS REPORT 6.9.1.14 Core operating limits shall be established and documented in the CORE OPERATING LIMITS REPORT before each reload cycle or any remaining part of a reload cycle for the following:

R146

1. Moderator Temperature Coefficient BOL and E0L limits and 300 ppm surveillance limit for Specification 3/4.1.1.3,

2. Shutdown Bank Insertion Limit for Specification 3/4.1.3.5,

3. Control Bank Insertion Limits for Specification 3/4.1.3.6.

4. Axial Flux Difference Limits for Specification 3/4.2.1,

5. Heat Flux Hot Channel Factor, K(z), and W(z) for Specification 3/4.2.2, and

6. Nuclear Enthalpy Hot Channel Factor and Power Factor Multiplier for t-

7. OvectmecRemet Are ovateoweg beem "T SETPOWT MMETER. ME5 fpE SPEtsMC RT100 2.2.I

. . .M ine analytical methods ~useo tonermine tiie~ tW those previously reviewed and approved by NRC in:

1. WCAP 9272-P A,

• WESTINGHOUSE RELOAD SAFETY EVALUATION HETH000 LOGY". July 1985 (W Proprietary).

(Methodology for Specifications 3.1.1.3 - Moderator Temperature Coefficient, 3.1.3.5 Shutdown Bank Insertion Limit. 3.1.3.6 Control Bank Insertion Limits, 3.2.1 - Axial Flux Difference, 3.2.2 Heat Flux Hot Channel Factor, and 3.2.3 Nuclear Enthalpy Hot Cnannel Factor.)

2. WCAP 10216 P A.

• RELAXATION OF CONSTANT AXIAL OFFSET CONTROL F, SURVEILLANCE TECHNICAL SPECIFICATION", JUNE 1983 (W Proprietary).

(Hethodology for Specification 3.2.1 Axial Flux Difference (Relaxed Axial Offset Control) and 3.2.2 Heat Flux Hot Channel Factor (W(z) surveillance requirements for F, Methodology).)

3. WCAP 10266 P A Rev. 2, "THE 1981 REVISION OF WESTINGHOUSE EVALUATION H0 DEL USING BASH CODE *, March 1987, (W Proprietary).

(Hethodology for Specification 3.2.2 Heat Flux Hot Channel Factor).

4. WCAP 13631 P A.

• SAFETY EVALUATION SUPPORTING A MORE NEGATIVE EOL H0DERATOR R161 TEMPERATURE COEFFICIENT TECHNICAL SPECIFICATION FOR THE SEQUOYAH NUCLEAR PLANTS.* HARCH 1993 (W Proprietary).

(Methodology for Specification 3.1.1.3 Moderator Temperature Coefficient)

... . The core operating limits shall be determined so that all applicable limits v R146 (e.y.. fuel thermal-mechanical limits, core thermal hydraulic limits. ECCS limits,9Ca uc g

5' WCAF- 87VS-/- A "Dc.5/w ME5 St TM WM- TRIP ggypm y 'pivo TKgmA OVne7WPrR/17HAE AT y,,pe pgS " gpg7gpg M84 (W

• 2' hofA/f7Mb 21* AG O T# ##"'

(PimIoanoGy for Sfec!Ruf

"# amen ment Nos , 50. 64, SEQUOY }T~~\l(IT 2 34, 146, 161 N h 26, 1 A , .

$f 9

ENCLOSURE 2 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE ,

SEQUOYAH NUCLEAR PLANT (SON) UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 ' ,

(TVA-SON-TS-95-11)

DESCRIPTION AND JUSTIFICATION FOR RELOCATION OF OVERTEMPERATURE AND OVERPOWER  ;

DELTA TEMPERATURE EQUATION CONSTANTS TO THE CORE OPERATING LIMITS REPORT b

I 4 4 m

w g .

p w 4 4 ,

. . a Descriotion of Chanae TVA proposes to modify the Sequoyah Nuclear Plant (SON) Units 1. and 2

. technical specifications (TSs) to relocate the overtemperature delta

-temperature (OTAT) and overpower delta temperature (OPAT) r and K constant

< numerical values to the core operating limits report (COLR). This will be  ;

implemented by revising notes 1 and 2 in TS Table 2.2-1 to state that these values are presented in the COLR. The proposed revision will not change these values. -The required contents of the COLR, describ'ed in TS '

Section 6.9.1.14, will be revised to include the r and K constant numerical-.

- values. Lag compensation terms will be added to the measured AT and

. average temperature values. The r values associated with these compensators are not changed by this revision and are zero such that the affect on the equations continue to be null.

Reason for Chanae t

The existing equations in the SON TSs for OTAT and OPAT in notes 1 and 2.  !

of Table 2.2-1 include the numerical values for the equation constants of r and K. The relocation of these constant numerical values to the COLR will allow revisions to the specific values without requiring a license amendment revision. j Changes to these values could be required based on specific core load '

requirements and future analysis revisions. The proposed revision will allow -

these changes to be performed in accordance with 10 CFR 50.59 - i requirements. The addition of the lag compensation functions to the equations provides consistency with standard TS (NUREG 1431) and will allow the use of these lag functions if future analysis requires.

SON has also experienced OPAT turbine runback alarms on individual channels resulting in partial runback signals. During functional testing at power, as required by TSs, these occurrences could result in turbine runbacks or reactor.. 1 trips because the tested channel is placed in the trip condition completing the, -

required logic for actuation. The r and K constant numerical values could be -

reanalyzed to provide additional margin to these setpoints and minimize the ,

potential for turbine runbacks, that could result in a reactor trip, and direct '

reactor trip signals. With the proposed revision, the changes'to'the rLand K:

values and use of the lag compensators could be implemented in a more timely: ,

manner under the requirements of 10 CFR 50.59.

i l

l l

1

-l 1

y .

1;c ., ,

?

7

~.

,w . . 1

. 2- ,

~ Justification for Chanaes--

1. .The OTAT trip provides core protection to prevent departure from nucleate j boiling for all combinations of pressure,' power, coolant temperature, and axial ,

-power distribution, provided that the transient is slow with respect to transit,_

thermowell, and resistance temperature device (RTD) response time delays' from the core to the_ temperature detectors, and pressure is within.the range between the high and low pressure reactor trips. This setpoint includes l 5 corrections for axial power distribution, changes in density and heat capacity of water with temperature and dynamic compensation for transport, i thermowell, and RTD response time delays from the core to the RTD output indication. With normal axial power distribution, this reactor trip limit is always ,

'below the core safety limit. 'If axial peaks are greater than design, as indicated : ,

by the difference between top and bottom power range nuclear detectors, the.

I reactor. trip 'setpoint is automatically reduced. ,

L The OPAT reactor trip provides assurance of fuelintegrity, limits the required' ' i range for OTAT protection, and provides a backup to the high neutron flux trip. i The setpoint includes corrections for changes in density and heat capacity of -

water with temperature, dynamic compensation for transport,' thermowell, and  !

RTD response time delays from the core to the RTD output indication. The j OPAT provides protection to mitigate the consequences of various' size steam breaks. ,

. The proposed revisions do not change the OTAT and OPAT functions in TS j Table 2.2-1. The relocation of the r and K constant numerical values'to the COLR will not result in a change to these functions or setpoints. _ Future .

i changes to these parameters will be performed under the 10 CFR 50.59 requirements to ensure the licensing basis of the plant and the accident '

analysis are properly maintained. In addition, as the numerical values may be cycle specific, relocation of these values to the COLR is consistent with the  :

guidance in Generic Letter 88-16.

p The addition of the lag functions to the measured AT and average temperature j terms will not change the OTAT and OPAT functions because these lag  ;

functions are presently equivalent to unity in the equations and plant. ,

instrumentation settings. Changes to the r numerical constant values associated with these lag functions will also be performed under the 10 CFR 50.59 requirements if future analysis requires. These lag functions are consistent with NUREG-1431 and have been omitted in the SON TSs be'cause their effect is presently null. The proposed revisions provide the flexibility to revise cycle specific values in the OTAT and OPAT functions and the ability to accommodtste revised plant analysis without requiring a license amendment request.

^

,9

~

.', s j I^

i Environmental imoact Evaluation

, The proposed change does not involve an unreviewed environmental question because operation of SON Units 1 and 2 in accordance with this change would i not-

1. Result in a significant increase in any adverse environmental impact i

_ previously evaluated in the Final Environmental Statement (FES) as - -

modified by NRC's' testimony to the Atomic Safety and Licensing Board,'. A supplements to the FES, environmental impact appraisals, or decisions of the Atomic Safety and Licensing Board.  ;

2. Result in a significant change in effluents or power levels. [

3. Result in matters not previously reviewed in the licensing basis for SON -

that may have a significant environmental impact.

-b j

i 5

t

7'je se

, ...9 ENCLOSURE 3 PROPOSED' TECHNICAL SPECIFICATION CHANGE SEQUOYAH NUCLEAR PLANT (SON) UNITS 1 'AND 2

. DOCKET NOS. 50-327 AND 50-328 -

(TVA-SON-TS-95-11)

DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION-5 i

1

-ev w. ..% p. -,c, +#-- . r-gr--v e _-_a a m._-.______

NP g7 ,

r c

lj t

l j

Significant Hazards Evaluation i TVA has evaluste'd the proposed technical specification (TS) change and has :

. determined that it does not represent a significant hazards consideration based on criteria established in 10 CFR 50.92(c). Operation of Sequoyah Nuclear  ;

Plant (SON) in accordance with the proposed amendment will not:

1. ' Involve a significant increase in the probability or consequences of an accident previously evaluated.

The proposed changes will allow changes to the constant numerical values '  !

for the overtemperature delta temperature (OTAT) and overpower delta ,

temperature (OPAT) equations in accordance with the .10 CFR 50.59 requirements. -This revision does not revise these constants, but relocates .  !

them to the core operating limits report (COLR) that is governed by the 10 CFR 50.59 requirements. The addition of the lag compensator i functions for measured AT and average temperature in these equations does not alter the setpoint because this lag function has a value of unity.

Therefore, the proposed revision does not alter plant functions"or- 1 setpoints, but does allow for a more timely revision process for parameters that may require changes due to specific fuel cycle requirements or updated plant analyses. The use of the lag functions and revisions to the constant numerical values will be maintained within the safety; analysis for the plant by the 10 CFR 50.59 process requirements. .The probability of an accident is not increased because the~ plant functions are not altered by the proposed revision and future changes will be in accordance with 10--

CFR 50.59. Additionally, the consequences of an' accident are not increased because the mitigation functions of the OTAT and OPAT functions are not changed and. revisions to the equations that derive the setpoints will be processed under the requirementa of.the 10 CFR 50.59 program.

- 2. Create the possibility of a new or different kind of accident from any previously analyzed.

The proposed revision will not change plant. functions and future revisions I will continue to be controlled in accordance with the 10 CFR 50.59 1 requirements. The addition of the lag functions does not create a new -  ;

accident potential because these functions have already been considered m the analysis as shown in NUREG 1431. Therefore, the possibility of a new or different kind of an accident is not created by the proposed revision.

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3. Involve a significant reduction in a margin of safety.

Plant parameters are not altered by.the proposed revision and the OTAT.

and OPAT functions will not reflect a change in setpoint generation or value. The proposed change will allow revision of the constant numerical values and use of the lag compensator functions in accordance with the 10 CFR 50.59 provisions to ensure the design basis of the plant is '

maintained. . This revision does not result in changes that r' educe the '

margin'of safety because the OTAT and OPAT functions remain unchanged and future revisions to these functions will be performed in accordance with 10 CFR 50.59.

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