Text

Proposed Revision to Tech Spec Sections 3/4.1.3.1-6, B 3/4.1.3,3/4.10.2 & 3/4.10.4 Re Movable Control Assemblies. Safety Evaluation Encl
	ML20054F780
Person / Time
Site:	Beaver Valley
Issue date:	06/10/1982
From:	; DUQUESNE LIGHT CO.
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ML20054F770	List: ML20054F769; ML20054F774; ML20054F780;
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	NUDOCS 8206170315
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REACTIVITt. CONTROL SYSTEMS 3/4.1.3 MOVA8LE CCffTROL ASSc'.MILIES GROUP _ HEIGHT LIMITIMG COMOITIOM FOR OPERATION 3.1.3.1 All full length (shutdown and ccntrol) rods shall be OPERABLE and posittened within + 12 staps (indicated position as 6detarmined in accordasca with S 3.1.3.27 corresponding. to their respective group demand comtar position.pecificattos MPLICA8ILITY: MODES 1* and 2*

ETICM:

With one or more full length rods inoperable due to being imiovable a.

as a result of. excessive fri~ction or mechanical interference or knamn to be untrippable, detaruine that the SHUTDOWN NAGIN requirement of Specification 3.1.1.1 is satisfied within 1. hour and be in HOT STAN08Y within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

b.

With more than one full length rod inoper21e or sisaligned frca the group demand counter position by more than + 12 steps (indicated position detemined in accordance with Specificatien 3.1.3.2), be in HOT STANOBT within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months , c.

With me full length rod.trippabie but inoperable due to causes other than addressad by ACTION a.above, e misaligr,ed from its group demand counter position by more than + 12 steps (indicated position determined in accordance with SpecifTeation 3.1.3.2), POWER OPERATICN may continue provided that within one hour either:

1.

The rod is restxed to OPERABLc status within the above aligtsient requi s ts, or 2.

The rod is declared inoperable and th) remainder of the rods in the.' ncup with the inoperable rx m aligned to within + 12 steps g

of the inoperable' red while maintafoing the rod sequenca~and insection limits of Figures (3.1-1) and (3.1-2); the TERMAL POER level shall be restricted pursuant to Specification (3.1.3.6) during subsequent caeratten, or 3.

The rod is declared i.werable and the SHUTDOWN MMGIN requirement of Specificaticn.3.1.1.1 is satisfied.

FCWER CPERATICM may then continue provided that:

a)

The nfEw4. Pcws icyc1 is reduced to less than or equei to 75 of RATED THEDtAL PQ2R within the hour 'and, wf this the next 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months the hign neutron fiu.x trip satpoint is reduced to less than x emal to 35% :f RATED Mwt PoiER.

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3/1 1-13 8206170315 820610 PDR ADOCK 05000334

. MOM 23 'r~AI.YG P

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LIMITIE CONDITION FOR OPERATICM IC atinued) b) The SHUTDQm MNtGIN rewirement.of Specification 3 l.1.l is detemined at least mea per 12 hars.

c) A power distribution. map is.obtained from the movable incere detectors and Fo(Z).and F4H.are verified to be. within their limits within.72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , d)

A reevaluation of each accident analysis.of Table 3.1-1 is perfarined within 5 days;'this esavaluation shall. confirm that the previously analyzed results of these accidents remain valid for the duration of cperation under these.caditions.

SURVEILL8nCE REQUIREMENTS 4.1.3.1.1 Each shutdowt.and control rod not fully inserted in the core shall be determined to be OPCUSLE by movement of at least 10 steps in any one direction at Taast once per 31 days.

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"See 5pec ui Tes: Ocactions 3.10.2 and 3.10.4 SEW /E. VALLEY - UNIT i 2/4 ?-IS

TABLE 3.1-1 ACCIDENT ANALYSES REQUIRING REEVALUATION IN THE EVENT OF AN IN0PERABLE FULL OR PART LENGTH R00 Rod Cluster Control Assembly Insertion Characteristics Rod Cluster Control Assembly Misalignment

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Loss Of Reactor Coolant From Small Ruptured Pipes Or From Cracked Large Pipes Which Actuates The Emergency Core Cooling System Single Rod Cluster Control Assembly Withdrawal At Full Power Major Reactor Coolant System Pipe Ruptures (Loss Of Coolant Accident)

Major Secondary System Pipe Rupture Rupture of a Control Rod Drive Mechanism Housing (Rod Cluster Control Assembly Ejection)

I BEAVER VALLEY - UNIT l 3/4 1-19a PROPOSED WORDING

.1EACTIVITY CONTR0t. SYSTEMS

_PCSITION INDICATION SYSTEMS-CPERATI E LIMITING CONDITION Tm CPERATION 3.1.3.2 The shutdown and control. rod position indication.systa shall be OPERA 8LE as follows:

. Group Deand Counter (I),1. per group

. Individual analog rod position instrument channel,1 per rod, + 12 steps (l) accuracf

. Automatic Rod Position Deviation Manitor(2),zegg f4,, erggy,g f, ja gaps U) During the f1rst hour during and following rod motion, the group deand countar is the primary indicator of precise rod position information,with the analog channels displaying general rod movment information. For power levels.below 505, a 1-hour thermal soak time ~is allowed before the analog channels are required to perfom within the specified accuracy.

(2) for pcwcr levels below 50% a one hwr thermal soak time is allowed.

Theeefore, if a Red Position Deviation Mon 1*or alam Jears itself within this.buur, the alars is censidered invalid.

SEAVER 7 ALLEY - UNIT 1 3/4 1-20 NCPCSD WCRDIM

LIMITI5G COMOXTICM FOR OPERATION (catinued) _

APPLICA8ILITY: MODES 1 and 2*

ACTION:

If the Rod. Position Indicating System indicatas(2) a potantially a.

misalip'15 minutesrod(s,'this indication shall be verified fummediately ed (within by sensuring the analog. rod position channel primary voltage.

If this measurement confirms that a red is misaligned, Specification 3.1.3.1.cis applicable.

b.

With a maximum of one group demand position indicator per bank'inct asle, either:

1.

Verify that all red position indicitors for the affected bank are OPERABLE and that the most withdrawn rod and the least withdrest rod of the bank are within a maxinaan of 12 steps (indicated position) of each other at least once per 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months , or 2.. Reduce THERMAL POWER to less than 505 of RATED TrlERMAL PQiER withia 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

With a maximum of one analog rod position indicator per bank inoperable, c.

either:

1, Determine rod position f:r the affected ro y measuring the l

detector primary voltage, as follows:

a.

Emediately b.

If tha associated rod moved greater 'than 6 steps (greater than 12 steos if all the rods in the group have been determined to be within 6 staps of group demand counter indicator by primary voltage measurements within the previous 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months ) l c.

At 4 hour4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months intersals if the affected rod (s) are*not fully inserted or withdrawn d.

At 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months intervals' if the affected rod (s) are fully inserted cr withdrawn, or, 2.

Reduce THERMAL POWER to less than 50% of RATED TdER.9L P0 DER within 8 bcurs,

d. With the Automatic Red Deviation Mcoiter incperable, ?CWER CPERATICE

=ay continue-provided that the deviation between the indicated positions is checked by the operator at least once per ~4 hours. The provisions of Specification 3.0.4 are not applicable.

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$1RVEIU.MCE REQUIREMDfTS 4.1.3.2.1 Each of the group demand counters shall be determined to be OPERAaLE by; a.

PerforTsing a CHAMEL CHECX b'y the' group demand counters.widin a bank, arx observing proper. overlap of the indicated. positions, at.lsest once per 7 days; and

.- a,s c A, A, M do fes ik & de p c' ~ W Performing a CHRMEL CHECX by an ' inter %.risa between the.cons b.

benchboard indicators and theAlagic.indicatars, and determining, M-ek

, their agrement within y,2 steps,. at least once per 92. days 4.1.3.2.2 Each of the analog rod position indicators shall be determined to be CPERABLE by:

Performing a CidAMEL. CHECK by interempari. son $ tween each. anal rod posi l

a.

tion indicator and.its.correspandf ag. group 6smand. counter at le t once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , b.

Performing a CHAMEL FUNCTIONAL TEST and CHAMEL CALIBRATIOR at least once per 18 months.

4.1.3.2.3 The Automatic Rod Deviation Monitor shall be determined to N (PERABLE by perfonning a agmese functional test at least once.per 7 daars, and the deviation between the position indicated by the individual analog rod positior instrument channel and the position indicated by the corrssponding group demae l

countar shall be checked ** manually for each rod at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

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"f or Core FHYSICS M1ING in Mode 2, primary detector voltage measurments may be used to determine the position of rods in shutdown banks A and B and control banks A and B fer the purpose of satisfying Spec.ification 3.T.3.2.

During Mode 2 operation, rod position indica. tors for shutdom banks A and B and control banks A and B may l

dsviate from the group deand indicators by greater than + 12 steps during reactor startup and shutdown operations, while rods are being witEdraut or inserted.

If

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the rod position indicators for shutdom banks A and S.and control banks A and B.

dsviate by greater than + 12 steps from the group demand indicator,d.

rod withdrawdl or insertion may continue until the desired group height is achieve IAen the desired group beight is achieved, a one hour soak time is allowed below 55 reactor pcwer to per:::it stabilization of the rod position analog indicators. To attain l

thennal equilibrium during f.he'one hour soak time, the absolute value of rod motion shall not exceed 6 steps.

i Vor power levels below 50f. cne hour thermal " soak tire" is permitted During this soak time, the absciute valve of rod action is limited to six steps.

5GER V.*L2f - UMT I 2 4 i-ICb ORCPCSED '.CRDIFG

REACTI'lITY CONTROL SYSTEM POSITICM INDICATICN SYSTEM-SHilTDOut LIMITING COMOITICM F(R OPERATION 3.1.3.3. The group step. demand counter and at least two analog rod position indicath channels per group shall be OPERABLE fcc. each group of thutdow or control rods not fully inserted.

APPLICABILITY: MODES 3 %.4*/ and M ACTIOM:

Bith less than the above required posit % imficAtor(s) OPERABLE, famedf ately insert all rods or, tmediately open the reactor trip systen breakers.

SURYEILLMCE REQUIRENNTS 4.1.3.3 EachofthesbcVerequiredpositionindicator(s)shallbedeterminedto be OPERA 8LE by perfemance of Specifications 4.1.3.2.1 and 4.1.3.2.2.

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l cNitn toe reactor trip systen breakers in the closed position.

L ;,-_::: T= L Oce t':::-5. iG SEAYER VALLE7 - UMIT i 3/2 1-21 FRCPCSZD M IMG

REACTIVITY CONTROL SYSTEMS ROD DROP TIME I

i LIMITING CONDITION FOR OPERATION 3.1.3.4 The individual full length (shutdown and control) rod drop time l

from the fully withdrawn position shall be <.2.2 seconds from beginning -

of decay of stationary gripper coil voltage to dashpot entry with:

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T,yg > 541*F, and a.

b.

All reactor coolant pumps operating.

APPLICABILITY:

MODE 3.

ACTION:

With the drop time of any full length rod determined to exceed a.

the above limit, restore the rod drop time to within the above limit prior to proceeding to MODE 1 or 2.

b.

With the rod drop times within limits but determined with 2 reactor coolant pumps operating, operation may proceed provided THERMAL POWER is restricted to:

1.

< 61% of RATED THERMAL POWER when the reactor coolant stop valves in the ncnoperating loop are open, or 2.

< 66% of RATED THERMAL POWER when the reactor coolant stop valves in the nonoperating loop are closed.

SURVEILLANCE REQUIREMENTS 4.1. 3. 4 The rod drop time of full length rods shall be demonstrated l

through measurement prior to reactor criticality:

For all rods following each removal of the reactor vessel head, a.

b.

For specifically affected individual rods following any main-tenance on or modification to the control rod drive system which could affect the drop time of those specific rods, and At least once per 18 months.

c.

. BEAVER VALLEY - UNIT 1 3/4 1-22 1

PROPOSED WORDING 1

REACTIVITY CCNTROL SYSTEM SHUTDOWN R00 INSERTION LIMIT LIMITI*i CGMDITICM RR OPERATICN 3.1.3.5 Al.1 shutdown rods shall be fully withdrawn.

l APPLICABILITY: N00E5 1* and 2*f ACTICM:

With a maximas of one shutdan. rod not fully) withdrawn, except for. surveillance testing pursuant to Specification (4.1.3.1.1, within one hour either:

a.

Fully withdraw the rod, or b.

Declare the rod to be inoperable and apply Specification (3.1.3.1).

SURVEILLANCE REQUIREMENTS 4.1.3.5 Each shutdown red shall be detarmined to be fully withdrawn by use of the group demand counters, and verified by the analog rod position indfcators**

a.

Within 15 dinutes prior to withdrawal of any rods in control bards A.

B, C or D during an approach to reactor criticality, and b.

At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter.

23ee spectai iest Esception 3.10.2 and 3.10.4

- fer pcwer levels below 50% one hour thermal " soak time" is per:sitted.

During this soak time, the absolute value of rod motien is limited to six steps.

With Xeff 2 1.0 CVD. VALLEY - UNIT 1 3/4 1-23 PRCFOSf3 WCRDInG

REACTIVITY CONTROL SYSTEMS CONTROL RCD INSERTION LIMITS LIMITIM CONDITION FOR OPERATICM 3.1.3.6 The control banks shall be limited in. physical insertien as shamn in Figures 3.1-1 and.3.1-2.

J MPLICABILITY: MODES 1* and 24 ACTION:

With the. control banks inserted beyond the above insertion. Ifmits, except for surveillance testing pursuant to Specification (4.1.3.1.1), eitherr l

t Restore the control banks to within.tha' limits. within 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months , or a.

i b.

Reduce THERMAL POWER within 2 hcurs to less than or equal to.that fraction of RATED THERMAL POWER titich is allowed by the group position using the above figures, or c.

Be in at least HOT STMDSY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

SURVEILLMCE RE0UIREMENTS 4.1.3.6 When the Rod Insertion Limit Moottor is OPERA 8tE, the deviation bits.

tha position indicated by the individual analog rod position instrument channel canually fcr each rod.at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .and the position indi When the Rod Ihsertion Limit Monitor at least once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .is in@erable, the deviation bewteen indicated positio

=5ee Special Test aception 3.10.2 and 3.10.3 Pvith K s e 1 1.0

- For p5h levels below 50%, one hour thermal "scak time' is permitted,0tring this soak time, the absolute valve of red stion is limited to six steps.

SE.%7.R VALLEY - LafIT 1 3/4 1-23a PRCFOSED WCRDI,'E

SPECIAL TEST EXCEPTIONS CROUP HEIGHT, INSERTION AND POSER DISTRIBUTION LIMITS LIMITING CONDITION FOR OPERATION 3.10.2 The group height, insertion and power distribution limits of Specifications 3.1.3.1, 3.1.3.5, 3.1.3.6, 3.2.1 and 3.2.4 may l

be suspended during 'the performance of PHYSICS TESTS provided:

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a.

The THERMAL POWER is maintained 185% of RATED THERMAL POWER, and b.

The limits of Specifications 3.2.2 and 3.2.3 are maintained and determined at the frequencies specified in Specification-4.10.2.2 below.

APPLICABILITY: MODE 1 ACT ON:

With any of the limits of Specifications'3.2.2 or 3.2.3 being exceeded while the requirements of Specifications 3.1.3.1, 3.1.3.5, 3.1.3.6, l

3.2.1, and 3.2.4 are suspended, either:

a.

Reduce THERMAL POWER suf ficient to satisfy the ACTION requirements of Specifications 3.2.2 and 3.2.3, or b.

Be in HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

SURVEILLANCE REQUIREMENTS 4.10.2.1 The THERMAL POWEP3shall be determined to be585% of RATED THERMAL POWER at least once per hour during PHYSICS TESTS.

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! BEAVER VALLEY - UNIT i 3/4 10-2 PROPOSED WORDING

SPECIAL TEST EXCEPTIONS PHYSICS TESTS LIMITING CONDITION FOR OPERATION s'

e' ThelimitationsofSpecifications3.1.1.h,3.1.3.1,3.1.3.5,and

' 3 ; 1.0. 4 e 3.1.3.6 may be suspended during the performance of PHYSICS TESTS provided:

a.

The THERMAL POWER does not exceed 5% of RATED THERMAL POWER, and b.

The reactor trip setpoints on the OPERABLE Intermediate and Power Range Nuclear Channels are set at 6 25% of RATED THERMAL POWER.

APPLICABILITY: MODE 2.

ACTION:

With the THERMAL POWER 25% of RATED THERMAL POWER, immediately open the ' reactor trip breakers.

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v SURVEILLANCE REQUIREMENTS 4.10.4.1 The THERMAL POWER shall be determined to be f 5% of RATED THERMAL POWER at least once per hour during PHYSICS TESTS.

4.10.4.2 Each Intermediate and Power Range Channel shall be subjected to a CHANNEL FUNCTIONAL TEST within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months prior to initiating PHYSICS TESTS.

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3/4 10-6 i

SEA'!ER VALLEY - UNIT 1 PROPOSED WORDING l

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- REACTIVVTY CONTROL SYSTEMS BASES 3/4.1.2 BORATION SYSTEMS (continued)-

The boration capability of either system is sufficient to provide a SHUT-DOWN MARGIN from all operating conditions of 1.0% ak/k after xenon decay and cooldown to 200 F.

The maximum boration capability requirements occur at EOL from full power equilibrium xenon conditions and requires 11,336 gallons of 7000 ppm borated water from the boric acid storage tanks or 49,917 gallons of 2000 ppm borated water from the refueling water storage tank.

With the RCS temperature below 200 F, one injection system is acceptable without single failure consideration on the basis of the stable reactivity condition of the reactor and the additional restrictions prohibiting CORE ALTERATIONS and positive reactivity change in the event the singl.e injection system becomes inoperable.

The boration capability required below 200 F is sufficient to provide a SHUTDOWN MARGIN of 1% ak/k after xenon decay and cooldown from 200 F to 140 F.

This condition requires either 5000 gallons of,7000 ppm borated water from the boric acid storage tanks or 175,000 gallons of 2000 ;,pm borated water from the refueling water storage tank.

3/4.1.3 MOVABLE CONTROL ASSEMBLTES The specifications of this section ensure that (1) acceptable power distribution limits are maintained, (2) the minimum SHUTDOWN MARGIN is maintained, and (3) the potential effects of rod misalignment on associated accident analyses are limited.

OPERABILITY of the movable control assemblies is established by observing rod motion and determining that rods are positioned within i12 steps (indicated position), of the respective group demand counter position.

The OPERABILITY of the rod position indication system is established by appropriate periodic CHANNEL CHECKS, CHANNEL FUNCTIONAL TESTS and CHANNEL CALIBRATIONS. OPERABILITY of the control rod position indicators is required to determine control rod position and thereby ensure compliance with the control rod alignment and insertion limits.

The OPERABLE condition for the analog rod position indicators is defined as being capable of indicating rod position within i 12 steps of the associated group demand indicator. For power levels below 50 percent, the specifications of this section permit a one hour stabilization period to permit stabilization of known thermal drift in the analog rod position indicator channels.

During this stabilization period, greater reliance is placed upon the group demand position indicators to determine rod position.

Above 50 i

percent power, rod motion is not expected to induce thermal transients of

{ sufficient magnitude to exceed the rod position indicator instrument accuracy pf i 12 steps.

Limited use of rod position indication primary detector voltages tis allowed as a backup method of determining control rod positions. Comparison

'of the group demand indicator to the calibration curve is sufficient to allow

' determination that a control rod is indeed misaligned from its bank when primary

' voltage measurements are used.

Comparison of the group demand counters to the l bank insertion limits with verification of rod position with the analog rod t

i SEAVER VALLEY - UNIT I B 3/4 1-3 PROPOSED WORDING

REACTlVITY CONTROL SYSTEMS BASES position indicators (after thermal soak after rod moti'on) is sufficient verification that the control rods are above the insertion limits below 50 percent power.

Above 50 percent power, reliance is placed on the analog rod position indicator channels to assure that control rods are above the insertion limits.

The ACTION statements which permit limited variations from the basic requirements are accompanied by additional restrictions which ensure that the original design criteria are met.

Misalignment of a rod requires measurement of peaking factors and a restriction in THERMAL POWER.

These restrictions provide assurance of fuel rod integrity during continued operation.

In addition, y

those safety analyses affected by a misaligned rod are reevaluated to confirm that the results remain valid during future operation.

Continuous monitoring of rod position with respect to insertion limits and rod deviation is provided by the rod insertion limit monitor and rod deviation monitor, respectively.

OPERABILITY of the rod deviation monitor is verified by a functional test at least once per 7 days and by comparison of the indicated analog positions versus the respective group demand counters at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

If the rod deviation monitor or the rod insertion limit monitor is IN0PERABLE, the frequency of manual comparison of indicated rod position is increased to an interval of at least once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months .

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'5EAVER 7 ALLEY - UNIT 1 B 3/4 1-4 PROPOSED WORDING

ATTACHMENT B SAFETY EVALUATION This proposed change to the Technical Specifications is structured to provide the necessary Limiting Conditions for Operation, Actions and Surveillance requirements to assure that the maximum misalignment of movable control assemblies within a bank is always limited to a maximum of 224 steps (ie: 112 steps related to instrument accuracy plus an ad-ditional !12 steps maximum allowed indicated deviation).

This proposed change fully recognizes the various factors which have been determined through test and observation to have an effect on the rod position indi-cation (RPI) system.

These observed factors are as follows:

a) a steady state non-linearity of the indicated analog rod position versus the actual rod position; b) a transient inaccuracy caused by substantial rod with-drawal which causes a thermal transient which alters the magnetic coupling of the RPI cetector coils, and c) a power level related shift of the RPI calibration curve which is suspected of being related to the increase of upper head temperature as reactor power level increases.

These three phenomena which affect the accuracy of the RPI system have been addressed as follows:

a)

The steady state non-linearity of the RPI analog indicators will be compensated for by performing calibrations of the analog RPI system and developing " custom made" RPI meter scales which compensate for the non linearity of the Instrument system.

To establish accuracy and operability of the rod deviation limit alarm, higher order equations which represent the actual RPI cali-bration curves within !2 steps, if possible, will be installed in the plant computer which generates this alarm.

Provisions have been made to appropriately increase the frequency of manual sur-veillance of RPI instrumentation should the rod deviation alarm be inoperable, b)

The time related thermal transient effecting RPI accuracy is addressed by allowing the reactor operator to place greater reliance on the digital group demand position indicator at reactor power levels below 50 percent for the permitted one hour soak time which is the maximum time required to allow the RPI analog instrument system to come to equilibrium.

Rod cotion during this soak time is limited to an absolute value of 6 steps to avoid creating a thermal disequilibrium ef fecting RPI analog indicator accuracy.

Appropriate specifications are included to assure the accuracy of the digital group demand indicators.

For power levels above 50 percent, the magnitude of rod motion encountered in normal operation is such that the magnitude of calibration shif t due to rod motion will be less than the maximum allowed indicated rod deviation of 212 steps.

Use of the " custom made" RPI meter scales eliminate the ef fect of instrument non linearity and will, in ef fect, increase the margin available to accomodate calibration shifts due to rod motion.

c)

The magaitude of instrument inaccuracy due to reactor power level has been observed to be within the range of 3 to 6 steps, depend-

Attachment B Pags 2 ing on location..This inaccuracy is well within the maximum allowed instrument inaccuracy of 212 steps.

The existing specific restrictions prohibiting adjustments to the RPI signal conditioners has been removed while fully realizing that the instrument accuracy requirements of the channel are clearly delineated by specificaticn 3.1.3.2.

Therefore, if adjustments of the signal conditioner of an RPI channel is required, compliance with specification 3.1.3.2 shall be demonstrated by a multipoint check of the calibration over the entire instrument range by insertion of test signals.

Testing has demonstrated that measurement of analog rod position h

by measurement of RPI primary detector voltage is a reliable and repeatable method to determine rod position.

Testing has also demonstrated that primary detector voltage is less ef fected by the thermal phenomena in-fluencing RPI accuracy than is the actual analog indication.

Therefore, the capability to determine rod position by primary detector voltage measure-ments has been retained as a_ backup method under strictly limited conditions.

This proposed technical specification has been substantially redrafted to remove complexity and ambiguity existing in the present specification and to set forth requirements in a clear, logical and easily understood manner.

Important in this respect is the clear direction in 3.1.3.2 that an indicated misaligned rod, verified by primary voltage measurement, requires the application of specification 3.1.3.1.

Special Test Exceptions 3/4.10.2 and 3/4.10.4 have been revised to conform the numbering of references to proposed section 3/4.1.3.

This change is considered to be purely editorial in nature.

The Bases (B 3/4.1.3) has been revised to reflect the technical con-siderations which form the bases for the related proposed specifications.

These proposed technical specifications represent an improvement in the requirements, limitations and methods of determining rod positions to assure compliance with the limitations set forth-in the core safety analysis related to rod position and rod deviation.

This proposed specification fully envelopes all the inaccuracies of the RPI system which we have observed and measured, is satisfactory from a human factors standpoint and provides appropriate controls necessary for safe operation of the reactor in a com-prehensible manner.

The Onsite Safety Committee and the Offsite Review Committee have reviewed this proposed technical specification and have determined that:

1)

The proposed technical specifications do not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated in the Safety Analysis Report.

2)

The proposed technical specifications do not create the possi-bility for an accident or malfunction of a dif ferent type than any evaluated previously in the Safety Analysis Report.

Attachment B Page 3 3)

The proposed technical specifications do not reduce the margin of safety as defined in the basis for any technical specification.

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ML20054F780

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