ML19325C913

Safety Evaluation to Justify Operation W/Loss of Jet Pump Flow Indication for Quad Cities,Units 1 & 2.

ML19325C913
Person / Time
Site:	Quad Cities
Issue date:	03/31/1989
From:	Chao G, Hamon D, Sozzi G GENERAL ELECTRIC CO.
To:
Shared Package
ML19325C905	List: ML19325C904 ML19325C913 ML19354D371
References
DRF-A-3243, DRF-A00-03243, EAS-07-0289, EAS-07-0289-R01, EAS-7-289, EAS-7-289-R1, NUDOCS 8910180087
Download: ML19325C913 (21)

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ATTACHMENT $

FAFETY EVALUATION T0 JUSTIFY >

OPERATION WITH LOSS OF. '!

JET-PUMP-FLOW INDICATION  !

FOR  !

, LQUAD CITIES UNITS 1 AND 2~  ;

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L' G. H. Chao -

D. A. Hamon . .

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' Approved-by: t") / /A L G.' L. Sozz7, Mada@r -

F , Plant Performance Eligineering

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5 IMPORTANT NOTICE REGARDING l4 CONTENTS OF THIS REPORT ,

i i Please Read Carefully i

The only-undertakings of the General Electric Company respecting.information irr

.this document are contained in the contract between the Commonwealth" Edison 1 ,

Company (Ceco) and. General Electric Company for this report,-and nothing contained'in this document'shall be construed as changing the~ contract. 'The use

of thisLinformation by.anyone other than CEcc or'for any purpose other.than that' for which it is intended,?is not authorir.;d; and with respect to any unauthor-  !

ized user General Electric Company makes.no representation or warranty, and- '

' assumes no liability as to the completeness, accuracy, or usefulness of the-information contained in this document.

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i TABLE OF CONTENTS Section~ 1111e fast .

1. Introduction 1-1

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l 2.- Conclusion- 1 2.1 Core Flow Measurement  : 2-l'  !

2.2 ' Jet Pump Integrity Surveillance .2-1 2.3. Effect on ECCS Performance Analysis '2-1 I

-3._ Core Flow Measurement. I3-1. I 3.1::Brief Description of Measurement System 1

- 3.2c Simulation of Lost ' Jet Pump Flow signal 3-1 t

-3.3. MeasurementLUncertainty Analysis 2- .:

3.4 ~Effect on Core Flow Measurement Uncertainty 3-4' H - 3.5 - Effect of Accuracy on Safety Limits Calculation .3-5 4.: l Jet Pump Integrity Surveillance, 4-1 .

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l. 4 '.1 Recirculation. Pump' Speed-Flow Characteristics 4-1. '

4' 2' Indicated'Versusl Actual Core Flow.

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4'.3. Alternatives. .

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4.4' Other. Considerations 4-3~

'4.5 ' Summary 4-3  :

L ly - 5. Effect on ECCS Performance-Analysis '5-1 L

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6.. References ~ 6-1 ]

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l'. INTRODUCTION L'oss of flow indication from jet- pump No. 7 at Quad Cities Unit 1-has occurred 1

- due to failure.of a sensing line inside the vessel. An evaluation was made to. l determine the effect of this failure on plant operation and safety. Loss of

. flow indication for up to'three-jet pumps was also evaluated for Quad Cities

Units'l and 2.- The scope of _the-evaluations includes the following:

1. The effect on core flow measurement accuracy.under 'two-loop and

' single-loop operation for the loss of jet pump-flow indication from:

l a) Jet pump No. 7 only (to be allowed at all times under proposed' Tech Specs),.

.b) Jet pump.No.'7'plus one additional jet pump (to be allowed until the next cold shutdown under proposed Tech-Specs), and-c) Jet pump No. J7 plus two additional ' jet pumps (to be allowed for

~ up to 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />s-following the ~1oss of indication from the third.  ;

jet pump under preposed' Tech Specs). ,

.For Quad Cities Unit 2, any single-tap jet pump can be substituted for  ;

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Jet Pump No. 7.  ;

2. The effect on the ability to detect a jet pump failure using the ..

surveillances as described in current Tech Specs.  :

3. The.effect on the ECCS performance analysis.

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- 2. : CONCLUSIONS l i

i 2.1 Core Flow Measurement Jet Pump No. 8 should- be used to simulate the flow of Jet Pump No.- 7 in the core- '

. flow measurement system.- Similarly, if flow indication is lost in additional jet pumps, they thould+ be simulated by their partner jet pump on the -same riser.1 Loss of flow indication for Jet Pump No. 7 was found to have a negligible effect on the overall core flow measurement accuracy. Loss of flow indication .>r a calibrated (double-tap) jet pump' results in;an increase of about 0.17% in the'

), overall core flow measurement-uncertainty for two-loop operation and 0.34% for

-single-loop operation. Based on these changes, plant operation with loss of I flow indication in up to-three jet pumps is acceptable as long as each jet pump is'on a different riser and no more than one calibrated jet pump per loop is  :

3 affected.

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. '2 . 2 Jet ~ Pump lIntegritySurveillance . :

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- Current plant instrumentation is adequate to detect whether any jet pomp 1 displacement is occurring tehich might impact jet pump integrity. The plant; Technical Specifications on jet pump integrity should be modified to replace the core pla2e AP versus core flow criterion with monitoring of individual jet pump flows 'This change is necessary because the existing criterion may not be met if_ cisplacement occurs in the jet pump which has lost flow indication.

2.3 Effect on ECCS Performance Analysis Any leak' from up.to three jet pumps to the downcomer annulus through the instrument line would be too small to have an effect on the ECCS performance N analysis. i l.

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.3. CORE FLOW MEASUREMENT i

c '3.1L Brief Description of Measurement System On typical jet pump BWR plants like Quad Cities Units 1 and 2, there are a total of 20 jet pumps. All of the jet pumps are provided with a single-tap (ST) I diffuser-to-plenum AP transiritter. The total core fbw passing.through 20-jet  ;

pump diffusers is duermined by.the single-tap AP transmitter of each jet pump. *

?The AP sign'al from each individual jet pump is electronically square rooted to -

- obtain a signal . proportional to flow and then st.mmed with other jet pump flows ~ ,

y to obtain the jet pump loop flows (i.e. sum of 10 jet pump ~ flows) and the total.  ?

core flow-(i.e. sum of two lop flows),

In addition,- four of the jet pumps:are provided with a double-tap (DT) diffuser-to-diffuser. AP transmitters. These four jet pumps (No's 1, 6, 11, and 16), are

laboratory calibrated prior to ins.allation at the plant, and are referred to as calibrated or double-tap jet pucips.- During initial plant.startup, the flow-

• - through these four calibrated jet pumps is calculated from the double-tap -

Emeasurement system, and two calibration constants per loop are developed. The L Laverage of these two calibratian constants for a loop is then used to calibrate *

- the 10 single'-tap instruments in the loop, so that the loop. flow indicators and -

core flow recorder read correctly. This cc.libration process is conducted periodically throughout the' life of plant to compensate for instrument drift and 4 other changes in the. recirculation system operating characteristics.

3.2 Simulation of Lost Jet Pump Flow Signal Since there is no-accurate flow signal from jet pump No. 7 for Unit I due to the severed instrument line, a substitute signal is needed. The substitute signal

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should be accurate enough- to prevent a significant increase in core flow measurement uncertainty,' convenient for input into the core messurement system, and enable surveillance for jet pump integrity. The single-tap flow signal from 3 the other jet pump on the same riser (i.e. No. 8) will best meet the objectives which are= mentioned above. Therefore, these evaluations are based on the 3-1

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assumption that jet pumps withno- flow indication will be simulated by,their

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respective partner jet pump on the .same riser.

The' simulation is based on data collected during previous jet pump surveillance.

tests at the plant. The data is analyzed to establish the relative difference

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between the flows of the jet pump on-the riser. The' failed sensed fiow is'then:

r j N(failed) ' N(jet pump on-th's same riser) (E)

.where.K and its uncertainty are established from plant historical data.: The simulation is implemented by wiring.the unfailed signal to the summer input for the failed sensing line' and adjusting the' summer input signal scaling for that-

. input which corresponds to the value of K.

L 3.3 Measurement Uncertainty Analysis l

l The core flow measurement system accuracy depends on many-factors. The major 3 L

k contributors to the. uncertainty, assuming no system faults, are:

L . 1. The differantial pressure measurement instruments for both the single-and double-tap system.

' 2. - The recirculation pump flow measurement which is used to determine the- a calibration constants for the double-tap. jet pumps.-

3. A sampling uncertainty due to only four of the twenty jet pumps being calibrated.

4 '. Uncertainties iri establishing the calibration constants for the double-tap jet pumps.

5. Changes in the recirculation system performance during the fuel cycle due to changes in the core pressure drop. This affects the jet pump M-ratio (suction flow /orive flow) which causes the calibration i constant to change.

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6. Instrument ~ drift during the fuel cycle until another calibration is .!t

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Differences from jet' pump to jet pump since their M-ratio.can: vary due:

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to the drive flow manifold distribution to'the jet: pumps.. '

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,~' L8. The ' accuracies of the c. ore flow measurem:nt system square-rooters and j summers.

GE Nuclear Energy has developed a.probabilistic model to calculate the total core flow uncertainty by considering the above plus many other less significant contributors.  :

j If- an-instrument sensing lir.e is severed,; additional uncertainties are intro . .3

duced due'to:1

1. . ' Uncertainty in the value of K used in the simulation as defined'in. .;

Section 3.2.

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2., .One 1_ess single-tap flow iaeasurement which increases the uncertainty. ,"

i: tin the summation process. The uncertainty of-19 measurements is 7 higher than the uncertainty of,20 measurements. .

L 3.- Forithe-double-tap system, additional- uncertainties- are introduced if-L 'here is one less calibrated jet pump measurement. The uncertainty of 3 measurements is higher than for 4' measurements. In~ addition, the sampling uncertainty increases since the sample ratio changes from 2 out. of 10 calibrated jet pumps per loop to-1 cut.of 10 in'one of the ,

loops.  !

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B7 modifying the original model for normal operation, an incremental uncertainty

.w; V due to the severed sensing line can be calculated.

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.3.4 Effect on Core' Flow Measurement Uncertainty:

( .Jsing the uiethod as described.in Section 3.3 and the jet pump surveillance test

'1 e , data:for Uniti1 provided by Ceco (Reference 1), the' total active coolant flow j

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uncertainties were cr1culated to be the' following for the indicated conditions: j

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Harmal Operation:

.-1. .2.01%. 15.00%

2.: Loss.of Jet Pump No. 7 only:

,. 2.01% _5.00%~

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3. Loss of Jet. Pump No.

7 plus-

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L one DT Pump:. '2.18% 5.34%

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4.- Loss of Jet = Pump No. 7 plus  :

.one.ST 1 one DT pump: 2.19%. 5.36%-

5. Loss of Jet Pump.No. 7 plus ,

. one DT. pump per loop:. 2.34% 5.64%

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' Loss 'of two 'DT.. pumps ik one. loop.was not specifically. evaluated, but would E result in a much highar uncertainty than " calculated for case 5. As can be'seen L' ifrom the above results, the incrennental- uncertainty ldue' to the ST pump is-negligible since the flow of-the jet pump is simulated by its partner on- the .l same riser. However. the loss of a calibrated jet pump signal has a more - ,

'significant,effect on the. accuracy for the reason discussed in Section 3.3.

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'The-total. core flow-uncertainties for Unit 2 were'also calculated based-on l h

historical jet pump data supplied by Ceco (Reference 2). The differences in the imeasured data between each jet pump pair on the same riser were found to be very ]

small. as was the' case- for Unit 1. Consequently, the contribution to the total

. core flow uncertainty due to the loss of flow indication in a Unit 2 ST jet pump

-is also insignificant. The contribution of DT jet pumps to the total core flow m.

uncertainty is, based on laboratory calibration prior to installation and'is thus L

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independent of- the_din' ividual- plant data. Therefore, the total Unit- 2 core flow uncertainties for the;various conditions listed above will be es!.entiilly .

identical to Unit l', except that Jet Pump No. 7 can be replaced by any ST jet

pump. .

. The changes in-total core flow uncertainties for. single-loop _ eperation with loss of flow indication:in.up to three jet pumps:have also been evaluated and are  :

summarized in the above table. These changes are 1&rger than for two-loop j

1. -operation'because the core flow meamement system is calibrateJ to' measure core flow when both"ioops of jet pumps are operating in; forward flow. For single-  ;

loop operation,-the-jet pumps in the inactive recirculation loop. vill experience -

p: - reverse flow.

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3.5 Effect of Accuracy on Safety. Limits Calculation- 1 A.S.1 .Two-Loop Operation.

- The-accuracy required for the core flow measurement system is 2.5%. Thi s~ . ,

requirement-comes from the General Electric Thermal Analysis Basis (GETAB) which.

assumed a' core flow uncertainty of 2.5% in the derivation of the Safety Limit

. Minimum Critical Power Ratio (MCPR). As can be seen from the,results presented

. in Section 3.4, the loss of flow indication from one ST jet pump plus two DT-' jet- ti pumps:(one from each loop) still meets this requirement.

3.5.2 Single-Loop Operation A bounding value of 6% core flow measurement uncertaint, har been conservatively -

applied in the GETAB calculations for single-loop operation. The predicted '{

total con tiow uncertainty for Quad Cities Units ~1 and 2 dering single-loop operation with all jet pump flow instrumentation assumed operable is 5%

(Reference 3). For all cases summarized in Section.3.4, the worst case (Case 5) still meets the 6% requirement.

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'3.5.3 Conclus'ons-i 1

Based on the above results, it is concluded that plant operation.with loss. of' flow ;f ndication in: up to three jet pumps- is acceptable- as long 'as 'each jet pump "

Lis on 'a separate riser and;no more than one DT jet pump per loop is affected.

This conclusion' . applies to Quad Cities Units -1 and 2 under both tuo-loop and single-loop operating conditions. '

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'4. JET PUMP INTEGRITY SURVFhLANCE I y l, The-loss'of an accurate flow signal from any jet pump makes. it necessary to review the Technical Specifications that depend on thet flow signal to diagnose a jet pump. integrity problem (i.e., displacement cf the removable pertion of the [

jet pump). The current Techni:a1 Specifications require simultaneous occurrence -

of the' following two condittens to indicate loss of jet pump integrity ,

(a) The recirculatic pump flow differs by more than.10% from established speed-flou charactaristics, and p

(b) The ' indicated core flow is more than 10% greater than the core flow L value derived from established core plate AP-core flow relationships.

These criteria' are evaluated in the following paragraphs to determine if changes

.are needed when flow 'i.1dication from one or more jet pumps has. been lost.

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'4.1 Recirculation Pump Speed-Flow Charatteristics t

L Since this ratio does not depend-on the jet pump flow signals, it remains vaik'.

4' 2- !ndicated Versus Actual .t. ore Flow i

p Dat. from a BWR where a' jet pump beam failed was evaluated and it was determined  ;

l. that' the following differences between the actual core flow and core flow L indicated by the core flow measurement system would be expected to occur:

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- Effect of Failure in Partng.t.to Jet Pumo with Loit Flow Indication When the jet. pump displaced, the flow of the other jet pump on the same riser dropped by 45% and reverse flow occurred through the jet pur.p that' displaced. The reverse flow through the diffuser was approximately 142% of the normal forward flow. The 142% flow was indicated as 167% flow in the core flow measure:aent system since the system we.s calibrated for forward 4-1 1

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p - flow rather than reverse flow. :Since the core flow men'urement system did .

%' . not detect this as revarselflow, it' added the;167% rather than subtracting j

' it. l 1

When the_ failed jet pump flow is~ used.tn simulate the flow for the jet' pump q which has -lost. flow indication, iarce core flow measurement uncertainties j wil1~ result. Core flow measurement unortainties would be introduced 'due - I to adding 167% rather than subtra:: ting '142% for the. failed jet pump, and:

showing a flow of_167% rather than 55% of norma 11for the intact jut pump- .

This would lead to an uncertainty _ of. 21% of: rated core flow.1 J f' Effect of' Failure in Jet Puma'with Lost Flow' Indication '

When the failed' jet-pump flow is simulated by its-partner jet pump, then corc' flow measurement uncertainty will-- not be as large as the previous case. Core flow measurement uncertainties would be-introduced due to adding 55% rather.thanLsubtracting 142% for the failed jet pump. This-would lead to an uncertainty of 9.9% of rated core fi n.

. i Consequently,;the 10% indicated versus actual core flow criterien is marginal for detection of . displacement of the jet pump with lost flow indication.

l Consequently,- the Technical Specifications should be. modified to assure- '

y detection of a displacement. {

~4.3 ' Alternatives i

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[4 E-  :. Continued use of the pump flow versus pump speed is acceptable because this indication does not depend on the jet pump flow signals. However, the use of the total core flow versus core plate AP may be: misleading in determining whether jet pump integrity is maintained. If the failure occurs on a jet pump ,

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that has a failed instrumer.t line, ther, the change in core flow for the ,

corresponding core plate IP may be less than 10%. Therefore, it is recommended that this requirement- be re.noved from the Technical Specifications.

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c7 LThe individual jet pump flow devt. . ion' pattern will clearly indicate jet pump -

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displacement since the-indicated flow of the jet pumps on'the affected riser change ~by 45% and 67%. ..Therefore. monitoring of the individual jet pumps is ,

recommended as an alternative to core plate AP versus core flow for evaluating  ;

- jet pump operability with loss of-flow indication in one or more. jet pumps.- .

This method ' requires that if the ratio of the indicated jet pump flow of- any ir.dividual jet pump:to the mean flow of all jet pumps in that. loop with intact i instrument lines differs by more than- 10% from the characteristic value for that

. jet' pump,.then the jet pump may,be failed.

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With .these changes, a jet pump would then be considered inoperable due to possible failure-if both the pump speed versus pump flow and the individual jet pump flow deviatiorc occur simultaneously. ,

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4.4 Other Considerations P1 W. operation with loss of flow indication for two jet pumps on the same riser is not permitted. If this should occur, there is no way.to ensure that jet pump integrity is-being maintained for the affected jet pumps. Maintenence of jet pump integrity is required to demonstrate that the core can be reflooded to

- two-thirds core height following a large recirculation line break loss-of- '

- coolant accident.-- -

1.5 Summary l

L The current Technical Specifications for Quad Cities Units 1 and 2 are maroinal with regard to detection of displacement of a jet pump which has lost flow indication. To remedy this concern, replacement of the core plate AP versus  ;

core flow requirement with a requirement to monitor individual jet pump flows is l .; . recomended, f

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, 5. EFFECT ON ECC5 PERFORMANCE ANALYSIS The diffuser upper pressure taps are located at approximately the same-elevation ,

as the bottom of the active fuel. To minimize the signal noise and to account for any differences in' the velocity distrihtion at the diffuser entrance, there ]

are three 0.125 inch diameter holes at the diffuser entrance to measure the <

1.

static pressure in the diffuser.

A manifold connects these taps and the

- instrument line is connected to ,this manifold inside the vessel. If the jet  ;

pump instrument line should break inside the vessel, it would establish an j r.dditional leakage path through these taps to the downcomer annulus which would allow nter intended for core cooling to leak into the oowncomer and delay core refloou t ng. ,

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1- -The design. basis loss-of-coolant accident (LOCA) for Quad Cities Units 1 and 2-

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-is a recirculation. suction line break with a single failure of a DCJpower source

-which disables the riightPressure Coolant Injection (HPCI) System, one Core Spray L

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.(CS) System and two of the four Low Pressure Coolant Injection (LPCI) pumps. In-this case, core cooling is accomplished by the one remaining Core Spray System

- that injects inside the core shroud plus tha'two remaining LPCI pumps. During_ "

refloeding, the-leak through the instrument line would start to occur when the water level reaches- the bottom of the act.ive fuel. Leakage would continue as 1 the water level rises to the jet pump suction elevation which is at approx-imatelyttwo-thirds of the core height. This additional leakage was calculated to be less than 3 gallons per minute through the three 0.125 inch pressure taps l

in any one diffuser. Even if three diffusers were leaking at this rate, the L total; flow loss would amount to much less than 1% of the total 2005 flow avail-

'able. Previcus sensitivity studies have shown that a leakage increase of this magnitude has no effect_on ECCS performance limits. Consequently, no changes to L the current ECCS performance limit calculations are necessary.

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6.- P.EFERENCES .,  ;

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j. , - - 1. Jet pump surveillance test data for Quad Cities Unit 1, dated'

-September.18;.1972.

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- 2. Jet' punp base data for Quad Cities Unit: 2, QTP 1130-55.. Rev. 3, May 1980. '

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' ' - 3. Dresden Nuclear Power Station Units'2 e,J 3 and Quad Cities Nuclear- '

• Power Station Units 1 and 2 Single-Loop Operation, NEDO-24807, December 1980.

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On October 31,11972. Quadicities Unit One1 Jet Pump Number 7 instrument,line

,c :falled. . The failure of the-instrument line prevented the use of' flow-

~1ndicatiot directly from Jet. Pump 7. The proposals llsted below were evaluated;to determine the best corrective action to be pursued.

m.

",ff'- 11 . Repair of the damaged' instrument line.;

.2.- Replace'the jet pump 1 upper 1section.

3.- : Justify operation with-the' failed instrument line.

@ f the Damaand Instrument Line p Commonwealth 1 Edison:and General Electric had expended considerable effort to

! ;developia method of repatring:the failed instrument line in early 1975, A

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' full' scale mock-up was constructed by Genera 1 > Eleotric Eto test numerous tooling designs that could repair the instrument line. Based on this work, it

'was demonstratedithat repair-was not-feasible due to~the limited-access to the L -area and the close' proximity of-other instrument. liner which.could:be easily-

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' damaged.

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In'the eariy:1980s',~three'BWRs experienced jet pump instrument line failures.

p These, failures occurred on the middle-to upper;diffuserfsection of.the jet L

pump (as-shown below).

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l Li General' Electric has performed repairs oh broken. jet pump instrument lines p' -wlth proven techniquesLand available. tooling. -The " Type 1" break'shown above -

was repaired using shrinkable Nickel / Titanium Alloy Coupling-to replace the.

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broken section. The " Type.2, 3" breaks.shown above were repal. red using replacement mechanical 4 band clamps to secure the-instrument line back ontthe diffuser secticn.

The Quad-Cities instrument line break on jet pump 7 is similar to the Type I break above. This type of Dreak took a-General Electric team seven hour shifts to complete at a totcl cost of = approximately three million -dollars. In addition, !t must be noted-again that Quad-Cities instrument'line break is in a more restricted area. The repair work on the instrument.line for jet pump 7 could lead to instrument line failures for jet pumps 8, 9 and 10 due to the

.close proximity of these lines'.

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toniace the Jet Pumn Unner Section- ,

~Another proposed fix recommended by_ General Electric was to provide a new jet e pump upper section with a new instrument tap location. The tap and fittings, along with the instrument line would be shop attached. This new instrument line would be routed from the jet pump vertically up the interior side of-the reactor vessel wall, run circumferentially around the vessel wall for

approximately 90' and then be routed out of the vessel vir the existing control rod drive hydraulic. system return lir.e. '

Because of flow-induced vibration, the vertical portion of the instrument line would have to be supported at intermediate points. However, because of

' limited access and undev? loped underwater welding techniques, it is not  ;

presently felt to'be possible to attach the line directly to the vessel wall.

Therefore, a vertical suppoit, with the instrument line attached, would have to be developed.

E The horizontal section of the instrument line would likewise have to be ll supported-by the installation of brackets on the vessel wall. It has been ,

proposed to accomplish this through the use of a' lead-lined gondola which has

, a circular _ window which could be sealed against the vessel wall for radiation ,

_ exposure' control.- A welder could be lowered into the gondole to weld pads and ,

brackets on the vessel clad to support the proposed instrument line. This method has been completely speculative to date.

This replacement method of repair as described above may represent a possible  ;

solution, but it is'not felt to be a viable method for.several reasons:

a (A) It is undesirable to make the postulated modifications to the vessel internal clad and to the control rod drive return line.

4 (B) It is undesirable to have one instrument seasing line routed a3 ,

l described above because of its vulnerability to future damage during vessel maintenance work.

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l (C) The postulated gondola and other repair. methods have never been tried and appear to have many drawbacks.

l (D) The personnel radiation exposure related to this. repair would be very large.

(E) The-costs associated with this repair appear to be far greater than the benefits to be gained. -

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• f Justifv Oneration With the Failed instrument Line This method involves a technical evaluation to determine the effects of the a failed instrument line on plant operatioW and safety. Thisievaluation

- ' examined the effect.of the failed instrument line on the accuracy of the flow

. measurement.The effect and ability to detect a jet pump failure using the surveillanceLas described in current Technical Specifications and the effect

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on the Emergency Core. Cooling System performance analysis.- The analysis shows~

that centinued operation with a failed jet' pump instrument line is' acceptable as long'as-minor changes are made to Quad-Cities Technical Specifications.

GQEWSlQUS Based on the factors discussed above, safety, cost and further_ damage-to existing jet pump. instrument lines, Quad-Cities believes the prudent course of

' action is to pursue the Technical Specification change. The analysis

(Attachment 2) shows that operation with one. failed jet pump instrument line is acceptable.- See Attachment 3, Proposed Chances to Technical _ Specifications-for Quad-Cities Unit One Facility Operating License DPR-29;- Attachment 4, o Summary of Changes; Attachment 5, Safety Evaluation; and Attachment 6 L Evaluation of Significant Safety Hazards Consideration Jet Pump-L Instrumentation.

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