ML20217F000

Rev 0 to Usqe 96-0101, Control Room Envelope HVAC Emergency Makeup Flow Control Damper B2HEFCV9585 Temporary Mod

ML20217F000
Person / Time
Site:	South Texas
Issue date:	04/01/1996
From:	Cottam J, Kersey R, Thomas S HOUSTON LIGHTING & POWER CO.
To:
Shared Package
ML20217E962	List: ML20217E957 ML20217F000
References
USQE-96-0101, USQE-96-101, NUDOCS 9710070338
Download: ML20217F000 (14)

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l USQE 96 0101 REVISION O 4

k 10CFR50.6B EVALUATION l FOR Control Room Envelope HVAC Er'nor0ency Makeup Flow Control Damper 82HEFCV9686 Temporary Modification i

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9710070338 971002 '~

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' OPGP05 ZA 0002 Rev.4 Page 41 or44 10CFR50.59 Evaluations Form 2 .

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Unreviewed Safety Question Evaluation Form (Sample) Page 1 of 4 Unreviewed Safety Question Evaluation # 96 0101 Rev. No O Page 1 of to OriginatingDocument: T2 d6 305615 Sy s4sm HE W<

Rev. No. C

~~"~" Unit

~ TMS T Vep NOTE: 94 Attach 10CFR50.59 Screening Form or Ucense Compliance Review Form to this .

NOTE:

Use additional sheets as necessary to provide the bases.

A.1 l Does the subject of this evaluation increase the probability of occurrence of an accident previously evaluated in the Safety Analysis Report?

YES T NO Bases:

Refer to the bases on the following pages.

ll Does the subject of this evaluation increase the e consequences of an accident previously evaluated

( Bases:

in the Safety Analysis Report?

Refer to the bases on the following pages.

YES X NO lit Dr.,es the subject of this evaluation increase the probability of occurrence of a malfunction of equipment important to safety previously WS X NO evaluated in the Safety Analysis Report?

Bases:

Refer to the bashs on the following pages.

I IV Does the subject of this evaluation increase the consequences of a malfunction of equipment '

important to safety prsviously evaluated in the YES X NO Safety Analysis Report?

Bases:

Refer to the basps on the following pages.

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OPGP05.ZA 0002 Rev.4 Pase 42 or 44 10CFR50.59 Evaluations i Form 2 Unreviewed Safety Question Evaluation Form (Sample) Pase 2 of 4 Unreviewed Safety Question Evaluation # 96 0101 Rev.No. O Page l of 10 OriginatingDocument: T2 96 305615 Rev. No. 0 t- i A.2 i Does the subject of the evaluation create the possibility of an accident of a different type than any previously evaluated in the TES X NO Safety Analysis Report?

Bases: Refer to the bases on the following pages.

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11 Does the subject of this evaluation create the possibility of a

{ different type of malfunction than any previously evaluated in the YES T NO Safety Analysis Report?

Bases: Refer to the bases on the following pages. _

A.3 1 Does the subject of this evaluation reduce the margin of safety as defined in the basis for any Technical Specification? YES X NO Bases: Refer to the bases on the following pages.

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OPGP05 ZA 0002 Rev.4 Page 43 or 44 I 10CFR50.59 Evaluations Form 2 Unreviewed Safety Question Evaluation Form (Sample) Page 3 of 4 Unreviewed Safety Question Evaluation # 96 0101 Rev. No. O Page 3 of 1o OriginatingDocument: T2 96 305615 Rev.No. O SAFETY EVALUATION

SUMMARY

Problem Descriotion The control loop for Control Room Envelope (CRE) HVAC Emergency Makeup modulating damper B2HEFCV9585 was found to have a faulted flow transmitter following trouble shooting of the B train FHB Exhaust Subsystem Modulating Damper B2HFHV9507A (reference USOE 96 007, CR 9513602 and DCP 96-3056 310CFR50.59 screening). The flow transmitters and Main Control Board indicating controllers for the two dampers share a common 24 volt loop power supply. Attempts to identify the root cause of the behavior, or to modify the control wiring to mitigate the adverse effects of the behavior (see page 7), will not satisfy short term needs for maintaining the operability of the CRE HVAC Emergency Makeup modulating dampn controlloop, damper, and system. The temporary change being implemented to maintain the operability of the CRE HVAC damper and its associated filtration bank are the subject of this 10CFR50.59 FValuation.

Summerv of Chenoet to Resolve the Problem 1

k' A temporary modification is being performed to maintain the operability of the B train CRE HVAC Emergency Makeup Damper.

The change is to preset the dampler, then remove all power from the damper actuator positioning the demper at 1000 cim, ,10%,its post accident position. This mitigates the consequences of a failed flow control transmitter by preventing any actbation signals from opers'.ing the damper. This results in a fixed damper position.

Conclusion This evaluation concludes that an Unreviewed Safety Question is not created by the use of the temporary change to compensate for the potentialloss of the flow transmitter.

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OPGP05 ZA-0002 Row 4 Page 44 or 44 10CFR50.59 Evaluations '

i Form 2 Unreviewed Safety Question Evaluation Form (Sample) Page 4 of 4 Untev;cwed Safety Question Evaluation # 00-0101 Rev. No. O Page 4 of 10 OriginatingDocument: T2 96 305615 Rev. No. O B. 1. XXXX All of t e above questions were answered No; therefore, the originating document does involve en Unreviewed Safety Question. .

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2. One or more of the above questions was marked YES: therefore, the originating document involv6s an Unreviewed Safety Question. The originating document, as presented, shall NOT be implemented without prior approval by the NRC, Provide a recommendation for disposition of the Unreviewed Safety Question below. Refer to OPGP05 ZN 0004 for process!.ig licensing amendments. Further processing of this form to the PORC, Plant Manager and NSRB is n21 required. Notify Procedure Control that the evaluation involved an Unreviewed Safety Question so that Procedure Control can close the USOE number.

RECOMMENDED DISPOSITION:

Approve this evaluation for removing power from the B train Control Room Envelope HVAC Emergency Makeup Filter Electro Hydraulle Damper Actuator.

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PREPARED BY: R. P. Kersey W h aey, J/3/94 ORTGINATOR Date REVIEWED BY: J. B. Cottam Mh[ g/go/pj,

/ 'QUp{lFIED REVIEWER ' Date APPROVED BY: S. E. Thomas -

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DEPARTMENT MANAGER / Date PORC MEETING NO. 96*96L7. L,#pg,,g 3/d/

Date APPROVED BY: ~

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PLANT MANAGER Date REMARKS:

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, _ Unreviewed Safety Question Evaluation # 96 0101 Rev.No. O Page 5 ef 10

, Control Ro'om Envelope HVAC Emergency Makeup Flow Control Damper 82HEFCV9585 Temporary Modification i[

SUMMARY

Aghjanoascriotton ,

1 The controlloop for Control Room Envelope (CRE) HVAC Emergency Makeup modulating damper B2HEFCV9585 was i

found to have a fauhod flow transmitter following trouble shooting of the B train FHB Exhaust Subsystem Modulating Damper 82HFHV9507A (reference USOE 96 007 CR 9513602,and DCP 96 3056 310CFR50.59 screening). The flow transmitters and Main Control Board indicating controllers for the two dampers share a common 24 volt loop power supply. Attornpts to idbntify the root cause of the behavior, or to modify the control wiring to mitigate the .

adverse offects of the behavior (see page 7), will not satisfy short term needs for maintaining the operability of the CRE

HVAC Emergency Makeup modulating damper control loop, damper, and system. The temporary change being

! implemented to maintain the operability of the CRE HVAC damper ar'd its associated filtration bank are the subject of

. this 10CFR50.59 Evaluation.

Summarv of Channes to Resolve thd Problem -

A ternporary modificationis being performed to rr.alntain the operability of the B train CRE HVAC Emergency Makeup Damper.

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The change is to preset the damper,ithen remove all power from the damper actuator positioning the damper at 1000

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cfm.t.10%, its post accident position. This mitigates the consequences of a failed flow control transmitter by preventing any actuation signals from operating the damper. This results in a fixed damper position. ,

Conclusion l

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This evaluation concludes that an Upreviewed Safety Question is not created by the use of the temporary change to compensate for the potentialloss of the flow transmitter.

BACKGROUND i

System Deslan Basis

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The CRE HVAC System is designed to:

s. Assure habitability of the CR envelope and permit safe shutdown of the plant as may be required under any normal or emergency conditions,

b. Maintain ambient temperature conditions to provide operator comfort and to satisfy environmental requirements of equipment. The design bases of an . blent conditions, safety class, and seismic category are listed in Table 9.&1 and Section 3.2.

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c. Maintain the CR envelope at positive pressure to minimize any inloakage of possible contamination from the outside,

d. Satisfy the design requirements of limiting dose to CR operators following the Design Basis Accident (DBA) in accordance with General Design Critorion (GDC) 19 of 10CFR50 Appendix A.

Equipment, motors, and controls with safety functions (except for outside air and smoke) are suppfled from Class 1E power sources and are separated and redundant to meet the single fe'. lure criterion.

Surveillance of airborne radioactivity levels of the outside makeup air to the supply system is provided by the CR f wentilation inlet air radiation monitors. On a high gaseous radioactivity or safety injection (SI) signal, CR makeup is

-( cnd automatically diverted through CR air makeup filter units. These units contain high efficiency particulate air (HEPA) charcoal filters, lhls safety related system consists of three 50-percent capacity redundant trains, powered by three redundant, independent, Engineered Safety Features (ESF) busses. Thus the single active failure critorion is met.

Unreviewedbatety Question Evaluation # 96 0101 Rev.No. O Page 6,of 10 {

Control flo'om Envelope HVAC Eme' rgency Makeup Flow Control Darger B2HEFCV9585 Termorary Modi '

~( -System Descriotion The CRE HVAC System consists of three 50 percent et(Lity redundant equipment trains o> cept for the toilet / kitchen exhaust, heating, and computer rodm HVAC Subsystem which are nonsafety related. Two of the three trains are required to function during the folloWing modes of opera 9on: shutdown, hot standby, normal operation, postulated accident condition, and loss of offsite power (LOOP). The following describes the makeup air equipment.

Each Makeup Air Filter Unit consist of the following:

1) Electric Hester to reduce the moisture in the airstream to 70 percent relative humidity in order to protect and malnteln the efficloney of the carbon filters.

2) Profilters to increase the life of the HEPA filters. The profilters are designed for 85 percent efficiency based on the ASHRAE Standard 52 efficiency test.

3) HEPA Filters to remove redloactive particles fiom the airstream. HEPA filters are designed to meet performance requirements in accordance with the ' Standards for HEPA Filters' CRE HVAC Emergency Makeup modulating damper B2HEFCV9585 is on the outlet of the B train of the Makeup Filter Units.

The safety function of this electro hydraulic dempers is to maintain air flow through its makeup filter units constant at a nominal 1000 cfm.i.10% (each train) by compensating for any changes in the filter unit pressure drop. There dampers are normally closed, fall closed, and operate only when the corresponding filter unit fan is opers ting.

Accident Analysts Bases and Assumotions

{ The analysis of control room operator doses following a LOCA contain several explicit assumptions regarding the CRE

\ emergency makeup system. These assumptions are:

Makeup flow is not greater than 2200 cfm total.

Makeup flow entering an idle train is not greater than 235 cfm.

Unfltered inleakage is prevented by positive pressurization, except for 10 cfm assumed from passage through CRE boundary doors, in all cases, except for the delayed LOOP following a DBA (or DBA w/ LOOP while operating the CRE in the emergency makeup mode), the system operation before and after the T mod would be the same. The two exceptions would result in two CRE makeup trains delivering filtered makeup flow as designed, with a portion of the total makeup flow flowing out the idle filter train. The effective pressurization flow would be reduced to about 80%

. cf the flow without the bypass flow path. The remaining 80% pressurization flow is enough to ensure positive pressurization.

Standard Review Plan Iteauirements

-l The fo!!owing Standard Review Plan sections are appilcable to the Control Room Envelope HVAC System:

- 6.4, Control Room Habitability System

. 6.5.1, ESF Atmosphere Cleqnup Systems 9.4.1, Control Room Area Vientilation System 1

The applicable accepttnce criteria from SRP 6.4 are 11.3 and 11.6. These criteria require pressurization at 1/8 inch w.c.

and limited radiation doses to control room personnel. Applicable SRP 6.4 review procedure 111.3 ovaluates the system

. to establish parameters to be used in the control room dose calculations. These parameters are CRE volume, filter efficiency, filtered makeup flow, unfiltered makeup flow, unfiltered inleakage, and filtered recirculated flow, f The applicable acceptance criteria from SRP 6.5.1 are ll.D and ll.E. These criteria are based on meeting the relevant i requirements of General Design Crithria 61 and 64 using Regulutory Guide 1.52 and by moeung the following:

The ESF atmosphere cleanup systems should be designed so that they can operate after a design busts accident (DBA) and can retain radioactive material after a DBA. The system:: should have provisions to profilter sir, remove moisture and meet the RG 1.52 requirements for charcoal adsorption. The systems should be redundant, be designed to Seismic Category I requirements, be able to actuate automatically, and be limited I

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, Unreviewed,Mfety QuestSn .: valuation # 98 0101 -

Rev.No. O Page 7 ef 10

- Control Room Envelope HVAC Emergency Makeup Flow Control Damper 52HEFCV9tA5 Temporary Modification to an air flow rate of approymately 30,000 cfm.

SRP_6.5.1 review procedure 111.2 lo6ks for compliance with t.he critoria specified above.

The applicable acceptance criterion from SRP 9.4.11s l1.5. This critorion establishes that the design of the control room area vent;istion is acceptable if it meets:-

General Design Crlierlon 60, as related to the systems capability to suitably control release of gaseous radioactive effluent to the environment._ Acceptance is based on meeting the guidance of Regulatory Guldes 1.52 and 1.140 as related to design, testing, and maintenance criterla for atmosphere cleanup system and normalventilation exhaust system air filtration and adsorption units of light water cooled nuclear power plants.

Position C.2, and Positions C.1 and C.2 respectively.

The applicable review procedure from SRP 9.4.1 is Ill.3.c.). This states that the system is acceptable if the total system has the capability to detect and controlleakage of airborne contamination into the system.- it is acceptable if the system P&JIDs show monitors located in the system lntakes that are capable of detecting radiation. The monitors should actuato alarms in the contred room.

. Safety Evaluation Report The NRC staff concluded in the SER that STPEGS meets the applicable acceptance criterla. SER 6.4 concludes that the control room habitability system of the South Texas facility is acceptable and meets GDC 19, with respect to maintaining the control room in a his and habitable condition under accident conditions by providing adequate protection against radiation.

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(' SER 6.5.1.1 concludes that the control room makeup air and recirculation cleanup systems are adsquetely designed to control the concentration of radioactive materials and pressure within the controt room in accordance with applicable regulations following a postulated design basis accident.

- In SER 9.4.1.1, the staff concluded that the control room envelope ventilation system was in conformance with the applicable General Design criteria relating to protection against natural phenomena, maintaining proper environmental limits for equipment operation, occupancy of the control room under normal and accident conditions, and the design cf the filtration systems to limit radioactivity.

,[Jg HVAC Emeroenev Makaue Electro hydraulle Modulatino Damner 82HEFCV9585 Descriotion The safety funct;on of the electro-hydraullo damper is to malntain air flow through the makeup filter units constant at

. a nominal 1000 cfm,:t,10% (each train) by compensating for any changes in the filter unit pressure drop. These

dampers are normally closed, fall closed, and operate only when the corresponding filter unit fan is operating. - The damper actuator is electro-hydraulic, and Inherently falls as-is on loss of power. The fall closed featcre is provided by an altomato power supply from the class 1E station batterw with logic that switches from the normal AC power to the alternate power, and drives the damper closed, if the normal power is lost.

This failed closed feature is intanded to stop flow through the filter trein tf the power supply to the filter heaters is lost.

Flow Indicating controllers provide automatic control of the damper to maintain constant air flow. They have adjustable flow setpoints and provide en indication of the air flow on the main control panel.

__ Fallure Mechanism Descriotion for Cr.E HVAC Emeroenev Makeuo Modulatino Dameer B2HEFCV9585 t The controlloop for this modulating dampers was exhibiting an adverse condition following switchover to the backup power supply. During surveillans testing, and subsequent troubleshooting, a failure of the associated flow transmitter cccurred. It appears the particult sequer.co of loss of AC power to the FHB HVAC Exhaust Subsystem filter train foll:wed by backup DC power operation is causing the CRE HVAC Emergency Makeup flow transmitter to fall. Fallure c.,f the flow transtretter or flow controller will cause the damper to move either fully open or fully closed. For additional 1

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Unreviewed 0st:ty Question Evalu: tion # 96 0101 Rev.No. O Page 3 af 10 Control Ro'om Envelope HVAC Emergency Makeup Flow Control Damper B2HEFCV9585 Temporary Modification*

discussion of the damper failure mechanism refer to CR 9513602 operability review (ST HS HS 033155) and the

l. 10CFR50.59 screening for DCP 96 3056 3. ,

j The root cause of the failure was under investigation at the time of this writing. The source of the failures has been identified to be bounded by the control and power circulty associated with th6 damper actuator but since the root cause has not been identified or resolved as of this writing, the plant must maintain filter train operability upon recurrence cf the condition.

Chanoen to Mitiaate the Effent of Falled Flow Transmitter for the Modulatina Dameer

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A temporary modification is being performed to maintain the operability of the CRE HVAC Emergency Makeup Damper.

The char.go is to preset the damper, then remove all power from the damper actuator positioning the damper at 1000 cfm.t.10E Its post accident position. This mitigates the consequences of a failed flow control transmitter by preventing any actuation signals from operating the damper. This results in a fixed damper position.

C ntinuous control of flow by the flow controller is not necessary to keep filter flow within the desired band.

Imonet of the Chance on Bases and Conditions Assumed for Other Safetv-Related Eauloment and Svateme Removal of normal and backup contgot power from the actuator effectively fixes the damper position and removes its

• Fall Close/Normally Closed" designation. The effects of positioning this damper open will not increase the dose accumulated by centrol room operators following a DBA, therefore the existing analysis remains valid and bounding.

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.k p:esitionchange has notoimpact remove on the normal andand cond tions 4ackup control power from the hydraulic pump and place the damper in a bases of other systems because the makeup / filtration function of the

' HVAC is maintained. The camper Isiplaced in a position to provide the nominal safe flow value of 1000 cfm.1,10E The fall closed feature of the damper is not considered a safety related function of the CRE HVAC system per 1.ER 94 005 and the CRE HVAC system FMEA, so deleting this feature does not change safety related furetions of the CRE HVAC. By maintaining CRE HVAC Emergency Makeup M'r Unit Electro hydraulic Modulating damper in the safe position, the system perforfr.J lts accident mitigation function at the same levril as when the damper is in the modulate mode. The bases for the accident, dose analysis are met and the consequences of an accident are therefore not increased.

A.1 I Does the subject of this evaluation increase the probability of occunence of an socident previously evaluated in the Safdty Analysis Report?

Bases: The CRE HVAC Eme'rgency Makeup Filter Unit Electro-Hydraulic Modulating dampers are idle normal plant operation. Placing the dampers in a position which supports socident mitigation (1. e.

satisfies the safety functions of filtration and makeup) cannot increase accident occurrence probabilities.

II - Dees the subject of this evaluation increase the consequences of en accident previously evaluated in

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the Safety Analysis Report?

Bases: By maintaining CRE HVAC Emergency Makeup Filter Unit Electro Hydraulle Modulating damper in the safe position, the system performs its accident mitigation function at the same level as when the

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I damper is in the modulate mode. The fall closed feature of the damper is not considered a safety-related function of the CRE HVAC system per LER 94 005. The bases for the accident dose analysis are met and the consequences of an accident are therefore not increased.

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i+ Unreviewed Sofety Question Evaluation # 96 0101- Rev.No. O Page e of 10-Cohtrol Ro'om Envelope HVAC Emergency Makeup Flow Control Damper B2HEFCV9585 Temporary Modification ,

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Does the subject of this evaluation increase the probability of occurrence of a malfunction of equlpment I important to safety previously evaluated in the Esfoty Analysis Report?

4 Bases: Probability of occurrgnce of a malfunction of equipment is not increased as a result of removing all motive power from the damesr. No new equipment is being introduced to the damper actuator assembly or contral bircuit, therefore no now potential unreliabilities are being introduced. Since the dampos is bolng placed in its safe position by this change and because it is being isolated from its motive power sources, its reliability would inherentlyjncrease. However, no credit will be assumed for enhanced reliability at this time.

With respect to oth 9r equipment and potential rrt functions of the system, the safe position of this damper is within the design basis of the Makeup Filter Units. The safe c9mper position therefore does not present a hazard to the Makeup Filter Units combined safe function.

IV Does the subject of this evaluation increase the consequences of a malfunction of equipment important to safety previously evaluated in the Safety Analysis Report?

Bases: Consequences of equipment malfunction previously evaluated will not inorsase. Pobitioning of the damper in its safe position before en event does not change the bases or assumptions in the accident

' dose analysis. The positioning cf the damper atits post accident position is an acceptable configuration -

with respect to CRE HVAC performance both before or after en accident including consid6 ration of a l single failure. The consegmes of previously e"aluated equlpment malfunctions are therefore not l Increased.

l l ( A.2 1 Does the subject of the evaluation create the possibility of an accident of a different type than any A previously evaluated in the Safety Analysis Repoit?

Bases: By maintaining filter train operability with the B damper in a fixed, safe position the system performs

- its accident mitigation function at the same level as when the demper is automatically modulated by its flow transmitter. No changes to plant, system, or component hardware are being introduced other than de energizing the power wiring to the actuator and changing the normal position of the damper from closed to its safe position to allow a nominal 1000 cfm. Because this part of the CRE HVAC system is only for accident mitigation, the possibility of an accident of a different type is not created.

The safe position of the damper is a design basis operational position for which the components are designed and tested to achieve and demonstrate performance. This change therefore does not create the possibility of a different type accident, il Does the subject of this evaluation create the possibility of a different type of malfunction than any previously evaluated in the Safety Analysis Report?

Bases: For the reasons discussed in A.2.1 above, the safe positioning of the damper does not create the possibility of a different type malfunction.

A.3 i Does the subject of this evaluation reduce the mar 01n of safety as defined in the basis for any Technical

. Speelfications7 Bases: The margin of safeth as defined in the basis for the Technical Specificat'.ons is not reduced. The applicable Technical Specification is 3/4.7.7, Control Room Makeup and Cleanup Filtration System. The

- Basis for this specification explains that the operability of the system is based on ilmiting the radiation f exposure to personriel occupying the control room to 5 rams or less whole body, or its equivalent.

T Effective filtration c( radioactive particles and effective pressurization of the control room envelope ensures that these d6se limits are not exceeded. The fall closed feature of the damper is not considererl a safety related function of the CRE HVAC system per LER 94 005. Because safe position of the damper maintains the performance of the system, the current dose limit predictions ar,e still valid.

Therefore there is no decrease in the margin of safety.

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Unreviewed Safety Question Evaluation # 96 0101 Rev.No. 0 Paes 10 cf 10 Control Ro'om Envelope HVAC Enwrgency Makeup Flow Control Damper 82HEFCV9585 Temporary Modification *

References:

1. Electrical Auxiliary Building HVAC System Design Bases Document, SV119VB1022 Revision 1

2. NUREG 0800, Standard Review Plan, Rev. 3 April 1984

3. STPEGS Safety Analysis Report (SAR) Chaptert,6,7.3,8.3,9.4,15, and Questions and Responses 4, STPEGS Technical Specifications

5. SYPEGS Environmental Report . Operating Ucense Stage

6. South Texas Safety Evaluation Report, NUREG 0781, April 1986 and Supplements 1 through 7

7. Calculation NC 6013 Revision S, Control Room, TSC, Offsite LOCA Dose

8. Temporary Modification T2 96 305615 Revision 0 i

9. ST HL AE 4799 dated 3/3/94, LER 94 005 " Damper Battery Backup Fallures*

10. CREE 96 305617, EvaluatiriD Operiting One CRE Makeup Train with Fixed Damper

11. USOE 96 007 Rev. O, CR 9513602, DCP 96 3056 3.

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, OPGP05-ZA-0002 Reve4 Page 38 of 44 I, 10CFR50.59 Evaluations Ponn1 l 10CFR50.59 Screening Form (Sample) Page 1 of 3 1

UNIT #1 UFSAR CN 'Tomp. Mod.

] DESIGN CHANGE [OTHER UNIT #2 BOTH ORIGINATING DOCUMENT NO. T2 96 305615 REV.NO. O DESCRIPT10N OF CHANGE Tempotory modificetions are being performed to maintain the operational readiress of the B trsin CRE HVAC Emergency Makeup Damper.

The change is to remove all power from the damper actuator and place the demper in its safe position. This mitigates the consequences of a tehod flow control transmitter by preventing any actuation signals from turning the hydraulic pump or changing the hydraulic clreult confin.retion. *.'nis results in a fixed, safe damper position.

PREUMINARY SCREENING YES NO

1. Does the proposed change represent a change to the Plant Technical Specifk.ations?

X

2. Is an Unreviewed Safety Question known to be associated with the subject change?

( NOTE: If "YES* to either questions 1 or 2 refer to OPGP05 ZN 0004 X

Does the proposed chervae represent:

3. A change to ordy correct a typographical, editorial or drafting errot?

4 A change which is identical to and addressed in he entirety by an existing approved 10CFR50.60 ScreerCng/USOE or NRC approved licensing submhtml?

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. 6. A spare o. replacement part/ component change with an equivalent part/ component?

, (See Section 2.3 for a defirdtion of equivalent) -

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6. A configuration change within exleting design specifications?

If all answers to the above questi If the artswar to any question (3) gns cia 'N0' perform the final screerdng and mark N/A in the approval blocks below.

through (6) is 'YES' a final screen 1ng is not necessary.

Sign opproval blocks below and discard pages 2 and 3.

Provide a justification and referendes if any of items (3) through (6) is answered 'YES".

l Prepared by: N/A I Originator Date

( Approved by: N/A k

Oustified Reviewer Date I

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(*. . OPGP05-ZA 0002 Rey.4 Page 39 et44 .

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10CFR50.59 Erduatitns Y'

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Form 1 10CFR50.59 Screening Form (Sample) Page 2 of 3 g .

Originsting Document No. T2 sS 305615 -

Rev.No. 0 l FINAL SCREENING in response to the questions belod,if the change involves something that le not described in the SAR and is not part of the licensing basis, the ',flQ' is appropriate. However, this deelslon must to clearly documented with odequate technical justification for sech question andlthe sections revlewed of applicable documents and applicable attributta revlowed should be indicated. The listing of ettributes and documente for 10CFR50.59 ocreening con be found in Addendum 6. .

Inter discipilns Coordination Required? NO -

If 'yes", obteln appropriate conewtonce. {YES

]R!sk and ReBability Anotysle , Thermal Hydraulice X Reload Eng. Ie b g, Civli Mech X Ele /l&Cde g [E0 Other 1.ce6ssh(Ts v t,Las en efA -

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1. Does the subject of this revisfw involve a change te the faculty as described in the Safety Analysis Report? g X

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Removal of power to the damper actuator will be performed such trist h does not impact flow or damper position Indication or operation of associated fans or heaters, in this respect it does not constitute a change to the facility es described in the SAR, however, the ability to automatically modulate will be defeated and the position will be fixed in the safe position lopen to support 1000 cfm.1,10%)

The lock of ab!!ity of modulating demper B2HEFCV9585 to be eutomatically moduisted by its controlloop constitutes e

( Aange to the f ac!!ity as described in the SAR. The dampar will be placed in a safe, fixed position and th6tefore mainteln the safe performance of the Control Noom Envelope HVAC Emergency Makeup Filter Units. The damper and its associated system will therefore mainteln operational reediness.

2. Does the subject of this review involve e change to the procedures as descrbed in the Safety X Aralysis Report? Rof ar to OPAP012A 0103.

No SAR procedure changes are proposed for malntaining the operability of the 'B' train emergency makeup fator bank of the CRE HVAC System.* Site proceduro changes are being performed to the applicable operating and surveillance procedures. These changes willbe consletent v.'Ith the licensing bases (SAR, SIR. SRP) for maintelning operational readiness of safety-refaled equipment and systems. This 'avel of system operation and testing, however ere

( beyond the detall of the licensing bases and therefore do not constitute a change to the procedures es described in the SAR.

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3, . . . OPGP05-ZA-0002 Reve4 Page 40 ore -

10CFR50.59 Evaluations Form 1 10CPK50.59 Screening Fonn (Sample) Page 3 of 3

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Originating Document No. T2 96 305615

• Rev.No. 0 YES NO

3. Does the subject of tNo review projose the conduct of test or emporimorte not described in the Safety Analysis Report? ,

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1 The temporary modification is to' temove oli power from the damper actuator and pleos the damper In its safe position. This trdtigates the consequences of er failed flow control transmitter by preventin0 any actuation signals from tuming the.hydraulio pump 6. changing the hydraulic circuit conf;puration. This results in a fixed, safe damper position.

• The changes maintain the operational readiness of the filtration bank such that no reduction in safety will occur. This change therefore does not constitute the conduct of tests or experiments not described in the SAR.

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4. Does the proposed change effect condhions or ba'ses assumed in the Safety Analysis Report X

( or safety related functions of, equipment / systems, even though the proposed change does not enteB eny physical change in existing structures, systems, or procedures se described in the SART

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Since the proposed change does affect existing systems as described in the SAR.further consideration of Impact on condittpns or bases assumed in the SAR ere discussed in Urveviewed Safoty Question Evaluation # 964101 l .

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If any enswer is affirmative, comp lete the screerdn0 form end perform an Unreviewed Safety Question Evolustion.

If all answers er negative, no Urveviewed Sefoty Question Evolustion is required.

R. P. Kersey M Propets by: ;w originetor I[J h d Date Approved by: J. B. Cottom Mg6h6 ousaed Re

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