ML17349A795

Nonproprietary Thimble Reduction Study for Turkey Point Units 3 & 4.

ML17349A795
Person / Time
Site:	Turkey Point
Issue date:	04/12/1993
From:	Savage C WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
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ML17349A792	List: ML17349A791 ML17349A793 ML17349A794 ML17349A795 ML17349A796
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A endix C Westinghouse Thimble Reduction Study for Turkey Point Units 3 and 4 (Non-Proprietary Version) 9304160074 9304i3 PDR ADOCK 05000250 P

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r Wcsuaghousc Class 3 Thimble Reduction Study for Turkey Point Units 3 and 4 Appmved by:

C. R. Savage, Manager Core Design B Nuclear Manufacturing Divisions 1993 by Westinghouse Electric Corporation

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This report documents a study performed for the Florida Power and Light Turkey Point Units 3 and 4, to address the issue of operating with less than 75% of the 50 total instzuaantation thiables in the core. The Wain ob]ective of this analysis vas to dateraine the additional peaking factor aeasureaent uncertainty that should be applied and addresses the NRC concerns vhen fever than 75% of the instruaentation thimbles are operational, The study is based on previous studies of a similar nature where re<<oval of <<ore than 75% of the operable thiwbles vas desired.

Because of the nature of the problea this study is statistical in natuze, and an exact answer cannot be defined. The folloving pages describe the aezhodology used for the study snd recoaaendations for applying the results.

Studies siaLlaz to this ha'. a been generated for other operating plants with tech specs requiring aoze than 75i of the instrumentation thimbles operational. Hovever, no perwanent technical specification change alloving a reduced number of operable instruaentation thimbles has been approved by the Nuclear Regulatory Co<<aission. httached is the NRC Safety Evaluation Report in response to a subaittal pwpaz'ed by Westinghouse. This SER states several concerns regarding the reduction of operating instnaantation thiables in the core (less than 75%)

during noraal plant operations. A ta<<porazy tech spec change has been granted for a current operating cycle based on the sub<<ittal; however, a peraanant tech spec change has not been granted because of the concerns addressed in the attached SER.

Zt is the intent of this study to satisfy these concezns in this regard in order to obtain a peraanent tech spec chang,e. The tvo aain issues frow this SIR are:

1) Per<<anent change of the tech spec vould lead to decreased level of Moveable Zncore Detector Systaa {lGDS) syste<<aaintenance.

2) The ability of the HSS systaw to detect ano<<alias in cases with large portions of the cora uninstnmented vould be unacceptable.

The follovtng <<aylains hov the above concezns <<ay be addressed; hovever, other concerns relating to rhiable reduction <<ay exist that are not knovn at this ti<<e.

Several studies haw been done vith peaking factor aeasureaent uncestaintias vhen less than the full cospleaent of instrumentation thiables are used in tha core. These studies vere used as a basis for deterwining the aagnitude of the uncertainty to be applied to measured peaking factors for the Turkey Point Qaits.

To daterafne the additional uncertainty in <<aasure<<ent of peaking factors. three full pover core pover distribution <<aps vere used tor reterebce. tive separate randoa thi<<ble reduction cases (down to 50%

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of the thimbles) vere done for each map -- a tocal of 15 reduced maps.

The measured peaking factors in the deleted maps vere then compared co the reference maps (vith all 50 thimbles). The additional measurement uncerrainties for 504 of che thimbles vere decermined from rhese comparisons. Uncertainties vere calculated for F> and F and che effects of thimble deletion on che axial offset and quadrant tilt vere also assessed.

As a r ult of these calculations an additional measurement uncertainty off free derernfned for P and an addirional neaaorenenr

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uncertainty of I divas dateemined for F . These values vere conservatively rounded to 1.0\ for F~ an8 2.0o for F . As an additional conservatism these values are doubled co 2.0i for F~ and 4.0t for F . These are the aaxiaum additional aeasurement uncertainties for F and F vich 50% of che instruaentacions thimbles removed. Current sPindard lech Specs define the uncertaincies ac 754 of thimbles reaaining, as 4.0% for F and 5.0% for Fz. Therefore, the cotal uncertainty in aeasurement of peaking factors Sich more chen 75i of the thimbles removed can be described by che funccions as follovs:

F hH aoasurement uncertainty 4\ + (2)*(3 - T/12.5)

F aeasurement uncertainty 5o + (4)*(3 - T/12.5)

Q vhoro T is the nuabor of operable thiables reaaining and muse be b etveen 25 an d 37 thimbles, inclusive. For cases vith greater than 37 thimbles operablo, the scandard Tech Spec uncertainties app 1 y ( 4.0% for F~ and 5.0% for FQ).

Although those uncertainties apply to reaoval of up to 50% of the thimbles, ~ base chiablo limit can be set. This liait vould be a minimum nuaber of thimbles (greater than or equal to 25) thee must remain oporablo. This is tho saao as having a aaxiaua number of thimbles (loss than or equal to 25) that can be removed from operacion.

Tho purpose'of this limit is to address the concern that large areas of tho core vould bo uninstruaentod.

The next section discusses the base thiable liait association vich the ainiaua number of thiablos por quadrant. h higher base limic resulcs in a theoretically greater number of thimbles per quadrant. And a higher nuabor of minimum thiables per quadrant results in smaller areas of the coro being uninstruaencod.

tilt Th urp Tho li iblf impact 0 thiable reduction on axial povor offset and quadrant is nog g o. Studies have shovn that the difference becveen recce thimble maps and tho referent maps is equal to or less thang g or axial pover offset andI J for quadrant tilt.

The peaking factor measurement uncertainty analysis described above s tion that thimbles vere randomly deleted from the core.

If thimbles are soaehov systematically deleteduncertainties froa the core t en t e above calculated peeking factor measurement vill noc

~ t 1: This section describes che calculations performed co esr,~bliss

e criteria for deteaaining vhether eltainatton of tnscrumentacion thimbles from the flux Napping system is random or systematic and also deterainea the bounds of applicability of the incremental peaking factor uncertainties.

both Turkey Point units (3 and 4) have a total of 50 instrumentation thimbles. h basic assumption of the peaking factor uncertaincies documented in the previous section ia that che removal of operable thimbles from che core is random in nature. The folloving defines exactly vhat random deletiona means in tera of the peaking feccoc uncertainty.

The assumption of random deletion of thimbles ts an important one. If removal of inatruaentation chtsablea tn the core ia completely random then each thtable in the core has an equal probability of being removed from operation. Therefore, if 50 percent of the chiablea in ehe core vere to be deleted randomly, a randoa pattern of thiablea vould result.

On the other hand,'f chere vere aose function driving the removal of the thimbles the result vould noc be a random pattern of thimbles.

This aysteaactc deletion of thiablea could concetvably result in large

~ ress oi the core betng untnstnuaented. If this vould occur the peaking factor uncertainciea vould no longer be epplicabl>>.

To help insure thee thisLble deletion ts random, ~ restrict .-n can be placed on ehe nuaber of thimbles that aust remain operable in each quadrant. For exaapl>>, if 50% of the thhables vere rgndoaly removed from the coze ie can be shovn chat/ g%f the time ac

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least ehree(3) thtablea vill be zeaatning tn each quadrant of the core.

If less than three(3) thiablea reaLatn in any quadrant a system'atic factor uncereainties could deletion vould be suspected and the ye not be applied.

To dateline the Rtniaua auxbez of ehtablea that vill reaain per quadrant tn a zendea deletion a aaa11 coeputer aiaulation code vas vctteen to arztva at a statistical solution. The core vaa dtvided into tvo seta of quadrants aa depicted in figures 1 and R. Figure 1 shove the coze divided toto four sections by cutting ie north to south and

~ aat to vest. This vill be zefezred to as quadrants Ql ehrough Q4.

Figure 2 ebon the core divided along the diagonals to fora four sections; these quadrants vill be referred to aa Qh through QD. Mhac this acceeplishaa ta to basically divide the cor>> into eight octants using evo aata of four quadrants each. These quadrants are all defined such that eha aaseabltea along the axaa dividing the quadrants are included in each of those adjacent quadrants.

The object of tha coepotar atssulatton ta to dateraiae the aintaum nuaber of ddablea zoaatning tn any one of these quadrants for ~ given perceneage of tha ehtablea 4aleted. The yrograa randoaly deletes ~

specified pezcentage of the total auaber of ehtGblea froa the pattern of thtable 1ocaetooa ahovn tn Ftguzaa 3 and 4. The reaulttng pattern ta then analyxed eo dateline the atnhaua nuaber of thimbles reaaintng tn any of tha eight quadrants defined abovai The coaputer akeulation vaa run for dalettona of 60% an4 501 of che thimbles vtth 5000 cases for each a~latton. The reaulea are tabulated in Table l. C

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ln summary, when 50i of che chiablos remain after a random deletion, at least three(3) thimbles should be left in each of cho eight quadrants.

If less than three thimbles aro loft in any quadrant,, then che'thimble reaoval is probably noc a randoa process and the peaking factor uncertainties calculated previously will no longer apply. (

of the tocal number of thiables vas not random; cho peaking faccor uncertainties no longer apply.

One of the NRC's main concerns was that a procedure for reducing the minimua number of operable thimbles would lead to reduced maincenance of the MIDS. To alleviate this concern an i.nitial scartup criteria can be added to tho requireaencs. This vould require that c minimum number of thimbles (904 for example) aust be operable at the scarc of a cycle. This vould assure adequate aaintenance of the MIDS.

Using tho additional peaking factor aoasureaenc uncertainties and requireaents for ainiaum nuaber of thimbles remaining per quadranc will provide ~ procedure acceptable for operation of the MIDS vith 50i ot greater of tho thimbles. However, no permanent Tech Spec change has been granted alloving a reduced number (less than 75%) of operable instrumentation thiables.

In sugary, the folloving recoasendations aro made to address the technical aspects of thiable reduction as well as the concerns of rhe HRC vhich have been voiced in the past. These recoaaendations are as follovs:

1) Peaking factor uncertainties: hdditional aoasuremenc uncertainties should bo applied co both F~ and F>. These uncertainties are applied in tho tora of Hie following

~ quations:

U ~ 2 o (3 - T/12.5) + 4.0 F

F 4 o (3 - T/12.5) + 5.0 vhere T is the nuaber of operable thimbles reaaining. And T ause between 25 (50%) and 37 (74%) inclusive. The

'ncercai.nti,es are expressed in percenc and include the nominal uncertainties.

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2) Ease thimble limit; h minimum percentage of thimbles remaining must be set. This study provides the ability to set the base thimble limit to 50%. Hovever, the higher the base limit is, the less concern regarding uninstrumented areas of the core.

3) Minimum number of thimbles per quadrant: In order to apply the peaking factor uncertainties a minimum number of thimbles must be in each quadrant. This minimum is dependant on the base limit set above. For a 50\ base limit the minimum number of thimbles per quadrant is three.

4) Startup minimum thimble Limit: To address the concern for reduced incentive of MIDS maintenance at startup, a minimusn thimble limit should be applied: This limit vould require that a minimum number of thimbles (90% for example) be operable at the start up of each cycle. h ma]or problem with reduced MIDS maintenance is the inability of the system (with a large reduction in operable thimbles) to detect mislosded assemblies at the beginning of a fuel cycle. Since the peaking factor measurement uncertainties calculated in this study assume a normal poser distribution map as ~ reference, the issue of aisloadad assemblies is not specifically addressed. The minimum thimble limit at startup vould resolve this concern.

Since MIDS is not a continuous an-line core monitoring system, nor is it a safety grade protection system it is the Vestinghouse position that its use in detecting or analyzing abnormal core conditions is a secondary function of the system. Its primary function is the verification of measured versus predicted core parameters on a periodic basis. Since the phi,losophy behind the purpose of the MIDS is debatable, the above recommendations may not satisfy the NRC concerns regarding licensing of the system below 75% of the thimbles operational.

Table 1 Thr~e Loop Core Geometry

.Turkey Point Units 3 and 4

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Q THERNXOUPlf (ST)

~ ?NCOttK lSVASL,E DETKCTOl5 {50)

Core Quadrants Defined by the Horizontal and Vertical Axes

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Core Quadrants Defined by the Diagonal Axes

C Attachment 1 NRC SER on Incore Detector Thtmble Reductfon Study

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~($ $ iQN ~ 4"- i' ~WCTU<, c. e. toeia Op~~4 SAPcCY EYALUATI ~ RERORT OFFICE OF NUCLEN REACTOR REGULATION INCORE DETECTOR THINLE DELETION STUDY 'o ~ ~ + m ~ ~ r ~ ~ gyg%0 ~ ~ ~ iNTRDDUCTION In a let:er daud Deeaaber )6, 1982, ~ ropcsed Chenge Request. Ho.75 to the Operating License o. Pomr Stat)on, Unht No. I. The reques. proposed to reduce the nuaber of th)ables required by the Techn1cai Speelfhcatkons ~s to 50 froa 75 for the encore movable detector systen to be operableo The licensee provided docsaentadon 1n letters 4ated January 4, 1983 end February 2l, 1 %3 support)ng an increase of the eovable encore detector map Ieasureient uncerta)nty as part of the chango request. Iy kaendaent Ko. 6l h dated January 19, 1983, wt provided fnterka approval of the proposed Technical SpeeffhcaUon change request for tbe emender of the then operating Cycle 3. Our intent)on was to complete the rev$ m of the sub)ect report. EVA~JAT~IK Essentially all Mt Technical Speeff)cat)ons contain a requirement for oper-ability of 755 of the encore 4atector locat)ons for perlodkc Iappkng of the core powr dkrCrlbutlon. On a nuiber of occas)ons, for various reasons, fa)lures fn operating NRs have approached or exceeded 25", and relaxathon of tha 75~ requkraient has been peraitted for the 4urat)on of affected reactor cycles. Ms has generally bean allness eNher 4th increased surveillance of soae sort (such as increased frequency of aapp!ng) or. as $ n the ease of the Inter& approval of th$ s change for Cycle 3 of lh3t I, Ken there $ s substantial sargkn to Technical Speckfkcatkon peaking fietor 11mfts. C; k r 8'h 3' 2 Ne advocate m1ntenance of as close to l00% operab111ty of the 1ncore detcc.~.- system as 1s poss1ble. Qe bel1eve that th1s 1s requ1red to be able to 1dent1fy and evaluate poss1ble power 41str1but1on or react1v1ty 11 ch a1ght occur dur1ny the operat1on of power plants. An exaeple 1s the burnable yo1son ro4 leach1ng probl~ that occurred 1n St. hc<'e 1 ~era the 1ncore 1nstneontat1on ms essent1al 1n Edant1fy1ng and unherstand1ng the ~blea. The 1S operab11)ty raqufraent was chosen to allow a reasonah'e anount of fa11 ures of the encore detectors, but to encourage the 11cansees to str1ve for as near. to 100S as poss1ble. petaanent Techn1cal Spec1f1cat1on changes to reduce the meber to SOS aught reset 1n a lack of 1ncant1ve to keep the sys'.e-operat1ng as close to 100~ es poss1ble. 1Ms could result 1n an unacceptab1 y degraded ab111 to detect anaaalous cond1t1ons 1n the core. Me therefore conclude that a permanent change of the . Undec 1 Techn1cal Spec1fkcat1ons to allow operat1on w1th up to 50% of the )ncore detector ih$ ab7es fa1led 1s not acceptable. h the event that the operah)11:y requ1~nt of 1$ % cannot be t during a c>le. we w111 cons1der 1nter1a Techn)cal Spec1f1cat1ons for the tmaknder of a cycle, as has been done before, Coes14arat1on veld ba given to available result1ng aarghn fran reduct1oo of operat5ny peak1ny factors Qth cycle hurnup, appl1cat1on of 'dDt1onal aeasur~nt uncerta1nt1es, and sore fraeent 1ncore oaoo1no. t ~tf: August Ego 1RS fr$ nc$ l Contributor: N. Ounenfeld attachment 2 Sample Technical Specification Modificationa lt p f' 'i l Insert h: When the auaber of operable aoveable detector thiables (T) is less than 75% of the total, the 5% F aeasureaent uncertainty shall be increased to (5% + (4)(3 . /12.5)f vhere T (the nuaber of operable thiables), aust be greater than or equal to 50i of the total. Insert B: @hen the nuaber of operable aoveable detector thiables (T) is less than 75% of the total, the 4% F aeuureaent uncertainty shall be increued to le+ (2)(3 - T/12.5)] vhere T (the auaber of operable thiables), aust be greeter than or equal to 500 of the total. Insert C: h ainiaua of three(3) detector thiables per core quadrant-- vhere tvo sets of quadrants are defined: 1) quadrants foraed by the vertical and hortxontal axes of the core and 2) quadrants foraed by the tvo diagonals of the core. These quadrants are defined such that the instruaented locations along the axes dividing the quadrants are included in each of those ad)acent quadrants as vhole thiables. Insert 9: ht least 90'f tho detector thiables aust be operable at the beginning of cycle. Insert E: U ia defined u the Base Load uncertainty factor that amounts for: aanufacturing tolerance, oeuureaent error, rod bov and aay buraup and pover dependent peaking factor increue!. Qith at least 75% of the detector thiablos operable, U is 9%. Rw the auabor of operable aoveable detector thHhlea (T) ia less than 75% of the total, the UBL uncertainty factor shall bo increwed to: t9e + (4)(3 - T/12.5)] vher ~ T (the auabor of operable thiables), aust be greater 'han or equal to 50% of the total. Insert F: V is defiaed aa the Radial Burndovn uncertainty factor tMt accounts for: leaaufacturiag tolerance, aeuureaent error, rod bov and aay buraup end pover dependent peaking factor increases. Wth at least 75% of tho detector . thiabloa operable, t4 is 90. Qhen the auabor of operable aoveablo detector thfRbles (T) ta less than 750 of the total. the U~ uncertainty factor shall be increased to: [9a + (4)(3 - T/12.5) t vhoro T (tho auaber of oporablo thiables), aust be greater than or equal to 50% of tho total. Y" Lj \I C't f POKER DISTRIBUTION LINITS 3/4.2.2 HEAT FLUX HOT CHANNEL FACTOR - F Z LIMITING CONDITION FOR OPERATION 2 2 ~2 Fqlti shell he 1 leltee hp the Folloesnp relstlonshlos: F~(Z) < [FO3 X [X(Z)] for P > O5 L Fg(Z) < I.Fq3 X [K(l)] for P < O.5 shore: [Fq] ~ 2.32 P e Thermal Power and K{Z) fs the function obtained fry Figure 3.2-2 for a gfven core height locat1on. APPL I CAB ILITY: NSE I ACTION: Kfth the measured value of FI)(Z) exceed1ng fts 1 fait:

a. Reduce THERNL POKER at least l% for each 1'S FI)(Z) exceeds Fq{Z) within l5 afnutes and sfaflarly reduce the Power Range Neutron F)ux - Kfgh Trip Setpofnts wfthfn the next 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> POKER OPERATION aay proceed for up to a total of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />; subsequent POKER OpERATIoN say proceed provided the Overpower Oelta-T Trip Setpofnts (value of Ki) have been reduced at least 1% for each 1% Fq(Z) exceeds the Ifeft; and s

b. ?dentffy and correct the cause of the out-of-lfaft condition prfor to increasing THERMAL POKER above the reduced power lfaft required by ACTlON a., above; THERNL POKER my then be 1ncreased provided FI)(Z) 1s denonstrated through 1ncore sopping to be wfth1n fts lfwft.

3/4 2-4 1 il. g g a I gt POWER OISTRIBUTION LIMITS SURVEILLANCE RE IRENENTS 4.2.2.1 If t.Fq] as pred1cted by approved phys1cs calculat1ons 1s greater than (.Fq]L and P 1s greater than PT as def1ned 1n 4.2.2.2, Fq(Z) shall be evaluated by 4.2.2.2, 4.2.2.3 or 4.2.2.4 to determ1ne 1f F< 1s w1th1n 1ts 11mft. If (Fq], 1s less than t:Fq] or P 1s less thdn PT, Fq(Z) shall be evaluated to detere1ne 1f Fq(Z) 1s w1th1n 1ts 11a1t as follows:

a. Us1ng the movable 1ncore detectors to obta1n a power d1str1but1on map at any THERNL PANNER gr eater than 5% of RATEO THERNL PNER.

bo Increas1ng the weasured Fq(Z) component of the power d1str1but1on sap by 3% to account for aanufactur1ng tolerances and further 1ncreas1ng the value by 5% to account for Neasu~nt uncerta1nt1es. Ver1fy1ng that the requ1rements of Spec1f1cat1on 3.2.2. are sat1sf1ed. Xc4Mlz~4,: Co Fq(Z) < Fq(Z) Nero Fq(Z) 1s the otasured Fq(Z) increased by the allowances for wanufactur1ng tolerances and Neasurement uncerta1nty and L Fq(Z) 1s the Fq 11a1t defined 1n 3.2.2. 3j4 2-5 QCj tk.j, POMER 0 STRlBUTION lNlTS SVRVEl ANCE RE 1RENENTS Cont1nued

d. Neasur1ng F~(L} accord1ng to the follcnr1ng schedule:

I. Pr1or to exceed1ng 75S of RATED THERNL RHEA, after refuel1ng,

2. At least once per 31 Effective Full Porkier Days.

e. @1th the relat1onsh1p spec1f1ed 1n Spec1f1cat1on 4.2.2.l.c above not be1ng sat1sf1ed:

1) Calculate. the percent F~(Z) exceeds 1ts 11a1t by the follow1ng express1on:

Nax1mn Fq(Z) X 100 for P > 0.5 Over Z rF(p x K{I)/{) lNx Fq(Z) X 100 for P ( 0.5 1'ver Z )))) )))/L) ~%P 1ncreased ) ) I heal )) ) ) ),) unt11 a peer level for extended operatfon has been ach1eved and peer 41str1but1on aap obta1ned. f" t t Y' r g< POWER DISTR 18UTION LIMITS SURVEILLANCE RE UIREMEHTS Contfnued

2) The followIng actIon shall be taken:

a) Comply with the requIrements of Specif)cat)on 3.2,2 for k Fq{Z) exceedIng Its lImkt by the percent calculate'd above+ 4.2.2.2 Operation $ s perm1tted at power above PT where PT equals the ratIo of (Fq]L dfvtded by [Fq] )f the followIng Augaented SurveIllance {Movable Incore Detection System, SIDS) requirements are satisfied:

a. The axial power distr)but)on shall be measured by HIDS when requIred such that the 1)m)t of fF<]"/P t$ mes FIgure 3.2.2 fs not exceeded. F~(Z) Is the no~I)ted axIal power distribution froa th)able ] at core elevation (Z).

l. If F~(Z) exceeds [F~(Z)]s as defined tn the bases by C 4%, )Need)ately reduce thermal power one percent for

~ very percent by which [F~{Z)]s 1s exceeded. 2e If F){Z) exceeds fF)(Z)]s by > 4% )sisedkately reduce thermal power below PT. Corrective act)on to reduce F~(Z) below the lfmtt All perm)t return to thermal power not to exceed current PL as defined In the bases. 3/4 2-7 'J h FH PO<R DISTRI BVTION LINITS SVRVE ILLANCE RE IRENENTS Continued

b. F~(L) shall be determined to be within limits by using ACIDS to ionitor the thimbles required per specification 4.2.2.2.c at the .

fol lowing frequencies.

l. At least once every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and

2. Ieeediately following and as a aknkwxxn at 2, 4 and 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> following the events listed below and every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> there-after.

1) Rais)ng the thermal power above PT, or

2) Novenent of control-bank D sore than an acconulated total of 15 steps $ n any one direction.

c. lllOS shall be operable when the thermal power exceeds PT with:

1. At least two thimbles ava)lable for which N~ and@'> as def)ned $ n the bases have been determined.

2. At least two NOvable detectors available for wapping F~(2).

3., The continued accuracy and representativeness of the selected th)wbles shall be verified by using the most recent flux alp to update the R for each selected thimble. The flux Nap aust be updated at least once per 31 effective full power days. 3/4 2-8 %F 7 POWER DISTRIBUTION LIMITS SURYEILLANCE RE UIREHENTS Cont f hued 4 .Z.Z.3 Base Load oper atfon fs permftted at powers above PT ff the fol'lowfng requfrements are satfsffed: t

a. Efther of the followfng precondftfons for Base Load operatfon must be satfsffed.

For enterfng Base Load operatfon wfth power less than PT, a) Hafntafn THERNL POSER between PT/1 05 and PT for at least 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, b) Nafntafn the AFD (Delta-I) to wfthfn a a 2% or a 3% target band for at least 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> per 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> perfod. c) After 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> have elapsed, take a full core flux map to determfne Fq(Z) unless a valfd full core f'lux map was taken wfthfn the i;fee perfod specfffed fn 4.2.2.ld. d) Calculate PBL per 4.2o2o3bo

2. .For entertng Bett Load operatfon wfth power greater than PT a) Hafntafn THERMAL POKR between PT and the power lfaft deter%fned fn 4+2+2+2 for at least 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and mafntafn Augmented Survefllance requfrements of 4.2.2.2 durfng thfs per fod.

b) Nafntafn the AFD (Delta-I) to wfthfn a e 2% or a 3% target band for at least 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> per 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> per fod, 3/4 2-9 tr 't POQER DISTRIBUTION LIIIITS SURYEII.LANCE RE UIREHENTS Continued c) After 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> have elapsed, take a full core flux map to. 4eterr[rfne Fq{Z) unless a valid full core flux map >>as tiken >>fthfn the tfae period specified fn 4.2.2.ld. d) Calculate PBL per i.2.2.3b.

b. Base Load operation fs pereftted provfded:

1. THERNLL PSKR fs aafntafned bet>>een PT and PBL or between PT and 185 (>>hfchever fs aost lfaftfng).

AFD (Delta-I) fs alfntafned >>fthfn a e 2% or e 3% target bands

3. Full core flux caps are taken at least once per 31 effective Full Po>>er Days.

PBL and PT are defined as: Nfnfew t;Fg" x x,(z) PBL Over Z <(7) x v(z) BL x ~~a ~ [FqlL/t;alp F~(7) is the ggysured F~(7)>>fth no allo>>ance for oanufacturfng tolerances or aeasuresent uncertafnty. For the PurPose of this SPecfffcatfon (FAN(z)3~p Neas. shall be obtained bet>>een elevatfons bounded by 1D% and %5 of the active core tslstt. [F(P ls tlvs Fll lia1t. K(z) ls <1vsn ln Ffgure 3.2-2. N(7)BL fs the cycle dependent function that accounts for 1 ferfted peer dfstrfbutfon transients encountered durfnfl base load operation. 3/4 2-10 P 1 ~ v) II POWER OISTR IBUTIOll LIMITS SURVEILLhNCE RE (IREMENTS Continued The function is given fn the Peaking Factor Lfmft Report as per Specification 6.9.1.6.

c. Ourfng Base Load operat1on, ff the THElNAL POWER fs decreased below PT, then the conditfons of 4.2.2.3.a shall be satisfied before re-enterfng Base Load operat1on.

d. If any of the conditions of 4.2.2.3b are not Nafntafned, reduce THEIWLL POWER to less thin or equal to PT, or, withfn 15 minutes initiate the Auyaented Surveillance {HIOS) requirements of 4.2.2.2.

4.2.2.4 Operation fs peraftted at powers above PT ff the following Radial Burndown conditions are satisfied: Radial Burndown operation fs restr1cted to use at powers between PT and PRB or PT and 1.00 (whfchever fs most lfaftfng). The saxi'elative power perwftted under Radial Burndown operat1on, PRB, fs equal to the afnf~ value of the ratio of Nus. where: (FAN(Z)3/[Fq(Z)3RB (Fq(Z)3R8 Was (Fly(Z)+p areas. x Fa{Z) x ~Uf(.8 and [Fq(z)3 1s seal to [Fg K(z). x

b. A full core flux asap to determfne fFxy(Z)]~p Seas. shall be taken wf thin the tfme per1od specf ffed 1n Section 4.2.2.1d.2.

For the purpose of the specfffcatfon, fFxy(Z)3~p Seas. shall be obtafned between the elevatfons bounded by 10% ind 90% of the acti ve core hefght. 3/4 2-11

fi 4(

POMER OISTR I BUTION LIMITS SURYE I LLNCE RE IREHEHTS Cont f nued c~ The funct 1 on Fz( L) prov'1 ded 1n the Peakf ng Factor Lfaft Report (6.9.1.6), fs detemfned analytfcally and accounts for the most perturbed axfal paar shapes Afch can occur under axfal power dfstrfbutfon control. l&&eWT gF Radfal Burndow operatfon say be utflfzed at peers between PT and PRB, or, PT and 1. (whfchever fs aost lfaftfng) provfded that the AFD (Delta-?) fs efthfn a 5% of the target axfal offset.

e. If the requfraaents of Sectfon i.2.2Ad are not aafntafned, then the peer shall be reduced to less than or equal to PT, or etthfn 15 afnutes layaented Survefllance of hot channel factors shall be 1nftfated ff the power fs above PT.

4.2.2.5. Mtwn Fq(l) 1s aeasured for reasons other than aeetfng the requf~ts of specfffcatfon i.2.2.1, i.2.2.2, 4.2.2.3 or i.2.2A in overall measured F~(Z) shall be obtafned floe a peer dfstrfbutfon aap and fncreased by 3% to account for aanufacturfng tolerances and further fncreased by 5% to account for eeasu~nt uncertafnty. )Q$ 8RZ"4: 3/4 2-12 ~-i g~ L tg ' ,P E vp i 4 ~ w t t t l') t f, ~ g ) I t t t iI I ION, 'IA I N ltOP,OP4) Q ae I 4 40 AS%,OA4 4 I 4a I O e 44 2 jV ON I 'I '1 I I 0 g~gl iQIOHT ~~ 's " Ij h POVER DISTRIBUTION LIMITS 3/4.2.3 NJCLEAR KNTHALPT RISE HOT CHANNE FACTOR LIHITING CONDITION FOR OPERATION 3.2.3 F<H Shill be Ifafted to the following: N FaH c l 062 fl gO + 0 3( 1 P)] 0 'rrhel e p I THERMAL POSER APPL I CAB ILI TY: NSE 1. ACT I OII: fifth F<HN exceedfng fts lfoft:

a. Nthfn 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> reduce THERNL POMER to less than QS of RATED THERMAL POWDER and reduce the Power Range Neutron Flux - Hfgh Trfp Setpofnt to less than or equal to 55% of RATED THGNAL PNKR ~fthfn the next 4.

hours'. Nthfn 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of fnftfally befng outsfde the. above lfafts, ver ffy through fncore flux aappfng that FaH fs restored to vrfthfn the above lfaft, or reduce THKRNL NMER to less than 5Z of RATED THERMAL . PofER efthfn the next 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.

c. Identffy and correct the cause of the out-of-lfNt condftfon prfor to fncreasfng 7%RNL PNER above the reduced THGNAL ~R 1 fmft requfred by ACTION a. and/or b., above; subsequent NEER OPERATION laay proceed provfded that F~ fs doaonstrated, through fncore flux aappfngi to be lrfthtn fts lfeft of acceptable operatfon prfor to exceedfng the follmrfng THERNL PotKR levels:

l. A eefnal 5{5 of RATED THERHAL PO{KR,

2. A ~fnal 75% of RATED THERNL PIN, and

3. Mfthfn 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of attafnfng greater than or equal to 95% of RATED THERHAL ONER 3/4 2-14

4 POWER DISTR I BUTION LIMITS SURVEILLANCE RE IREilENTS 4.2.3.; The prov1s1ons of Spec1f1cat1on 4.0A are not appl1cable. 4.2.3.2 F<H shall be determ1ned to be v1th1n 1ts 11N1t through 1ncore flux wappfng:

a. Pr1or to operat1ng above 75% of RATED THERE'LL POWER after each fuel load1ng, and

b. At least once per 3l Effect1ve Full Parer Days.

N 4.2.3.3 The measured F>H shall be 1ncreased by 4% to account for Neasut%5tnt errol' paDS6 RT'; 3/4 2-15 jA tr i! II

4) ',A g

rg.. INSTRUNENTATI ON HOVABLE NCORE ETECTORS LINlTING CONOITION FOR OPERAT ION 3.3.3.2 The sovab)e Incore Detectfon Systel shall be OPERABLE wfth: t a. At least 7g of the detector thfables, aJSFgT' Sufffcfent movable detectors, drfve, and readout equfpment to sap these thfrebl es. f ~sz.i D APPLICABILITY: Nen the Movable Incore Detectfon System fs used for:

a. Recalfbratfon of the Excore Neutron Flux Detectfon System, or

b. Honftorfng the QUADRANT PQMER TILT RATIO, or N

c. lfeasurment of F>N and Fq(>)

ACTION: fifth the Hovable Incore Dethetfon System fnoperable, do not use the system for'he above applfcable aonftorfn9 or calfbratfon functfons. The prov>sfons of Specfffcatfons 3.0.3 and 3.0A are not applfcable. SURV 1 RNKNTS 4.3.3.2 The Movable Incore Detectfon Systea shall be deaenstrated OPERABLE a: least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> by noraalfzfne each detector'utput when required for:

a. Recalfbratfon of the Kxcore Neutron Flux Detectfon System, or

b. Neftorfne the gVAQRNfT PotER TILT RATIO, or

c. Neas~ent of F and F~(Z) 3/4 3-36

'i