View source for JAFP-91-0228, Forwards Update of Status of Activities for Emergency Svc Water Sys Per NRC 901009 Request Re 900821 Enforcement Conference.Updated Response to Generic Ltr 89-13 Will Be Provided by 910430

{{Adams
| number = ML20073D934
| issue date = 04/15/1991
| title = Forwards Update of Status of Activities for Emergency Svc Water Sys Per NRC 901009 Request Re 900821 Enforcement Conference.Updated Response to Generic Ltr 89-13 Will Be Provided by 910430
| author name = Fernandez W
| author affiliation = POWER AUTHORITY OF THE STATE OF NEW YORK (NEW YORK
| addressee name = Hehl C
| addressee affiliation = NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), NRC OFFICE OF INSPECTION &amp; ENFORCEMENT (IE REGION I)
| docket = 05000333
| license number = 
| contact person = 
| document report number = GL-89-13, JAFP-91-0228, JAFP-91-228, NUDOCS 9104290296
| document type = CORRESPONDENCE-LETTERS, INCOMING CORRESPONDENCE
| page count = 1
}}

=Text=
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James A.Mt:Pstrick Nuctsar Power Plant
.        P.O. Box 41 Lycoming, New York 13093 316 342-3640 8D NewYorkPower
(# Authority                                                                                     Clam"L"!r""
April 15, 1991
;JAFP 91-0228 U. S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA               19406 ttn:            Mr. Charles W. Hohl, Director - Division of Reactor Projects

==SUBJECT:==
JAMES A. FITZPATRICK NUCLEAR POWER PLANT -
DOCKET NO. 50-333 UPDATE OF THE STATUS OF ACTIVITIES FOR THE EMERGENCY SERVICE WATER SYSTEM

==References:==
: a. NRC letter, C.W. Hehl to W. Fernandez dated October 9, 1990 regarding August 21, 1990 enforcement conference.
: b. NYPA letter, J.C. Brons to NRC dated January 16,   1990       (JPN-90-011)                          regarding proposed change    to                     the            Technical Specifications regarding             crescent                      area    unit    coolers improvement (JPTS-89-032) .
: c. NRC letter, D.E. LaBarge to J. C. Bronc dated April 11, 1990 regarding issuance of Technical Specification Amendment 156.
  \ttachments:               1. Update   of                   the              Status   of   Previous HRC Commitments presented at the August 21, 1990 Enforcement Conference
: 2. ESW System Testing Program
: 3. As-built Crescent Area Unit Cooler Control Configuration Description
   ] ear Mr. Hehl:
[n Referenco (a) the NRC staff requested that the Authority prepare snd submit a report summarizing the current status of known
:ommitments associated with the FitzPatrick Emergency Service Water lESW) System and the crescent area coolers.                                          The staff also asked
   . hat the Authority address the ESW system testing program, any ESW system related Technical Specification changes that the Authority light propose, and a revised response to NRC Generic Letter 89-13,
   ' Service Water System Problems Af fecting Safety-Related Equipment."
04290296 910415 R    ADOCK 05000333 PDR St    O l. Ih

\   ,.
U.'S. Nuclear Regulatory Commission                    April 15, 1991 Attn:    Document Control Desk                         JAFP 91-0228

==SUBJECT:==
JAMES A FITZPATRICK NUCLEAR                Page                         POWER PLANT -
DOCKET NO. 50-333 UPDATE OF THE STATUS OF ACTIVITIES FOR THE EMERGENCY SERVICE WATER SYSTEM NRC Generic Letter 89-13 The Authority will submit an updated response to NRC generic letter 89-13 not later than April 30, 1991.
ESW - Crescent Area Cooler Commitments Authority commitments associated with either the ESW system or crescent area coolers are summarized in Attachment 1. This-version reflects and minorthe current  status of ESW/ crescent area cooler commitments editorial improvements.         A previous version was distributed at the August 21, 1990 enforcement conference.
ESW Test Procram DescriDtion The Authority's ESW test program at FitzPatrick is summarized in Attachment 2. It briefly describes each of the surveillance tests, the test frequency and the components tested.
Technical Snecification Imorovements During    the August     21,  1990   ESW enforcement     conference,  the Authority identified the limitations of the " shut off head" .ESW pump surveili.ance test currently required by the FitzPatrick Technical Specifications.        The Authority will propose a Technical Specification change to revise the test requirements to be consistent with the appropriate portions of ASME Section XI-and the FitzPatrick inservice inspection and test program.                    The surveillance tests and minimum acceptance criteria will be similar to those approved by the NRC for other licensees. The test currently The under consideration will require relief from Section XI.
Authority will prepare and submit technical specification changes no later than September 1, 1991.
Update on Crescent Area Unit Cooler Modifications To improve the reliability of the crescent area coolers,              the Authority recently completed modifications that will reduce the potential for silt accumulation in the coolers. Instead of

    *U..S. Nuclear Regulatory Commiesion                 April 15, 1991 l    Attn:   Document Control Desk                       JAFP 91-0226 SUILTECT:   JAMES A FITZPATRICK NUCLEAR             Page                        POWER PLANT -
DCCKET NO. 50-333 OPDATE OF THE STATUS OF ACTIVITIES V)R THE EMERGENCY SERVICE WATER LYSTEM throttling cooling water flow to the coolers, continuous cooling water flow is being supplied to the coils of 8 of the 10 unit coolers. Control circuits were modified to actuate the cooler fans as a function of area temperature. Technical Specification changes associated with these improvements were submitted by the Authority (ReMerence b) and subsequently approved by the NRC (Reference c).
The carrent configuration of the crescent area unit cooler control syster is not consistent with the description included in the authortty's application.      A design change, prepared and approved after kmendment 156 to the Technical Specifications had been issued by the NRC,     reduced the number of coolers        affected by the modification from ten to eight.        However, the actual Technical Specifications pages issued by the NRC are unaffected by these alterations; the FitzPatrick Technical Specifications are correct and accurate. The conclusions in the Authority's safety evaluation are still valid.
The NRC Project Manager for FitzPatrick, after being notified of this change, asked that the Authority submit a description of the modifications as they were installed.        Attachment 3 is a brief description of the crescent area cooler control system as it exists today.
Any questions regarding the matters discussed above should be addressed to Mr. Christopher Ponzi of my staff at (315) 349-6564.
Very truly yours, f          j (V/
      )ILLIAM FERN    DEZ II
                   /
WP:CJP:bnrk Attachments' CC:   U.S. Nuclear Regulatory Commission Document Control Desk Mail Station Pl-137 Washington, D.C. 20555 R. Liseno        NRC Resident Inspector          RMS  (WPO)
V. Walz          J. Gray  (WPO)                 TS File DCC              R. Ram   (WPO)                  IST File

A. LER 88-009-01 COMMITMENTS                                                            STATUS
: 1. Install permanent instrumentation to monitor crescent cooler thermal               COMPLETE performance.
: 2. Siweekly crescent cooler testing until modifications are completed.                ON-GOING - Biweekly testing will continue until the current cooler performance reassessment is completed.
l    3. Modify crescent unit cooler fan and water controls to allow full water              COMPLETE l         flow, cycle the fan and install additional therr.:a1 performance instrumentation. The modification was to be installed prior to start-up from 1990 Refuel Outag':. The Completion date was delayed until September 30, 1990 (JPN-90-11). The modification has beer. completed.
B. RESPONSE TO VIOLATION 88 INOPERABLE CRESCENT COOLER &
COMMITMENTS                                                   ,
STATUS
: 1. Revise ST-19A to better measure cooler performance bi-weekly.                      COMPLETE
: 2. Clean and inspect coolers.                                                         COMPLETE
: 3. Reanalyze crescent cooler heat' loads to' demonstrate acc. , tab:e cc0 it with     r,0MPLETE service water temperature up to 82*F.
: 4. Modify piping to reduce accumulation of suspended solids.                          INCOMPLETE -
Modification: will be determined by the effects that full flow through the crescent coolers and chlorine injection have on silt and corrosion deposits.
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                                                                                                                                                                                                                                                                   ~
ATTACHMENT 1                                                                                              .       - ,
STATUS OF PREVIOUS NRC COMNI?4ENTS B.                                      RESPONSE TO VIOLATION 88 INOPERABLE CRESCENT COOLERS (couth ui d)                                                                                                                                                         l CONNITMENTS                                                                                      STATUS
: 5. Install larger mesh strainers.                                                                                                                 COMPLETE                                                                  '
: 6. Replace missing section of flanged pipe to UC-22J.                                                                                              COMPLETE
: 7. Revise piping arrangement to UC-22D.                                                                                                            COMPLETE
                                            '8. . Initiate performance testing of other service water-cooled safety-related                                                                      COMPLETE heat exchangers.
: 9. Maintain accelerated test frequency-for crescent area unit coolers until                                                                        DN-G0ING - Biweekly performance trend improves.                                                                                                                     testing will continue until the current cooler                                                  '
performance reassessment is. completed.
: 10. Review all[ Technical Specification surveillance requirements and ensure                                                                        COMPLETE they are: contained.in STs and are performed on schedule.
: 11. Establish System Engineering Group.                                                                                                             COMPLETE
: 12. . Reorganize the WPO Engineering Staff so that engineering personnel are                                                                         COMPLETE assigned exclusively to the Authority's nuclear plants.- -This corporate engineering organization reportsidirectly to the Executive Vice President-for Nuclear Generation.,
: 13. " Develop' Medification: Control Manual and . Design Change Manual.                                                                              PARTIALLY COMPLETE.
The Modification Control Manual is complete. The Design Control Manual has been implemented at the corporate office and is scheduled to be implemented at the Site by 7/1/91.
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                                                                                                                                                                                                 !?___'_______.____    _ _ _ _ _ . _ . . _ _ _ _ _ _ _ _ _ _

B. RESPONS_E TO VIOJ.ATION 88 INOPERABLE CRESCENT COOLERS (continued)
STATUS COMMITMENTS PARTIALLY COMPLETE (WACP
: 14. Develop a formal root cause analysis program.                             10.1.27) - The procedure for root cause analysis methodology has been implemented. An integrated causal action program has been             .;
defined. The imple-menting procedure is           '
being developed for initiation this summer.
C. RESPONSE TO VIOLATION 88 HIGH SERVICE WATER TEMPERATURE STATUS COMMITMENTS Revise FSAR to address 82*F lake temperatures. Awaiting incorporation     INCOMPLETE
: 1.                                                                             Safety Evaluation is-into revisior.                                                            complete. FSAR Change Request has been submitted and will be incorporated into the 1991 FSAR update.              !
COMPLETE
: 2. Train engineering personnel on 10 CFR 50.59 safety evaluation preparation and importance.                                                                                          l
: 3. Fonnalize the method for promptly evaluating deviations from the FSAR. COMPLETE (NGP-38)
COMPLETE
: 4. Train. plant management personnel on the reportability requirements of 10 CFR 50.72.
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ATTACHMENT 1 STATUS OF PREVIOUS NRC C0dMITMENTS L
D.       ENFORCEMENT CONFERENCE COMMITMENTS                                                                  STATUS
          .In addition to the commitments contained in Section (B) above, the Authority committed to the following:
         -1. Trend test data to establish testing and maintenance frequency to prevent                 CONTINUING flow restrictions.                                                                       Testing and maintenance is currently being reassessed. Trending of teste data will continue until reassessment is complete.
: 2. Evaluate the feasibility and necessity of testing other safety-related                   COMPLETE
!                coolers.
: 3. Develop administrative procedures describing the responsibilities and                    COMPLETE establishing the various channels to be utilized by the Systems Engineering Group..
i I
t I
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Y
  ,                                    ATTACHMENT 2                                ,
E8W SYSTEM TESTING PROGRAM
: 1. The safety-related heat exchangers listed below 'are or may be supplied cooling water by the.ESW. system.
emergency diesel _ generator jacket cooling wateri heat          '
exchangers (93WE-1A, -1B,'-1C, -1D) electric bay unit coolers (67UC-16A, -B) cable. tunnel /switchgear room'coolersE(67E-11, -14) control room and relay room air handling units (70AHU-3A,
                -3B,  -12A and -12B) crescent area unit coolers (66UC-22A, -B, -C, -D, -E,: -F,
                -G,  -H,  -J,  -K)
: 2. The following is 5 summary of surveillance testing procedures!
for the ESW system valves, pumps,-logic-circuitry and' heat exchangers..
ST-80, ESW Motor ODerated Valves' Operability Test *

== Description:==
-      ESW MOVs are cycled by their-control switches to verify proper remote manual operation.
Components Tested:         15MOV-101        46MOV-101A' 15MOV-102        46MOV-101B 15MOV-103        46MOV-102A-15MOV-175A       46MOV-102B 15MOV-175B i
Frequency:     Monthly.
(         ST-8D, E8W Pumo Flow Rate Test (IST)*                                  l

== Description:==
_The shutof f ' head of each pump is' measured-l separately-to. demonstrate;that the ESW' pumps.
satisfy the Technical. Specification flow.rato requirements.       The 'ESW MOVs are also stroke time tested during this--test for IST.
,         Components Tested:         46P-2A,B         ESW pumps l                                    46MOV-101A,B- . ESW system injection valves 46MOV-102A,B'    ESW system ^ test. valves Frequency:     Quarterly ~
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ATTACKMENT 2
: 2. Continued ST-8E,  ESW   Locic System     Functional  Test   and  Simulated        )
Automatic Actuation Test *

== Description:==
Demonstrates the ability of Reactor Building Closed Loop Cooling (RBCLC) pump discharge header    pressure- switches    and associated Lockout Matrix relays to cause Emergency Service Water Pumps to start and specific MOVs in the RBCLC and ESW systems to reposition to an ESW injection to RBCLC lineup.
Components Tested:
15PS-122A        pressure switches 15PS-122B 15PS-122C 15PS-122D 46P-2A,B         ESW pumps 15MOV-175A,B     ESW return to service water MOVs 46MOV-101A,B     ESW system injection valves 46MOV-102A,B     ESW system test valves Frequency:    Quarterly ST-8N, ESW Pump Inservice Test (IST)*

== Description:==
Each ESW pump is run in a standard lineup to permit collection of required IST data.        Pump discharge check valves and Emergency Diesel Generator (EDG) return line check valves are verified to open.
Components Tested:
46P-2A,B         ESW pumps 46ESW-1A,8       ESW pump discharge check valves 46ESW-6A,B       EDG return line check valves Frequency:   Quarterly ST-8P, ESW Return Check Valves Reverse Flow Test *

== Description:==
Verify EDG return line check valves close.
Components Tested:     46ESW-6A,B EDG return line check valves Frequency:   Once per cycle Page                                                                           ,

    ,                                    ATTACHMENT 2
: 2. Continued ST-80, Testina of the Emeraency Service Water System (IST)

== Description:==
The ESW flow rates to raw water heat exchangers is measured to confirm that flow rates - to the units meets the design- basis.               The test also demonstrates that various ESW check valves open.
Components Tested:;                          .
67UC-16A,B             electric bay. unit coolers 67E-ll',14             cable' tunnel /switchgear_ room coolers 70RWC-2A,B             control room chiller condensers 70AHU-19A,B.           control, room chiller' room coolers
                     .66UC-22A to K- crescent-area _ unit coolers 93WE-A,B,C,D           EDG jacket water coolers-46ESW-1A,B             ESW-pump discharge check. valves 46ESW-6A,B             EDG return'line~ check valves 46ESW-7A,B             ESW _to . control     rm. _ equip. check valves 46ESW-9A,B             ESW to-reactor building check-. valves-46ESW-13A,B            ESW'to crescent cooler check valves                  s Frequency:    Quarterly BT-8R, Emeraency Service Water Check Valve Test (IST)*

== Description:==
The proper operationL of interfacing ' : ESW and normal service water check valves is verified by flushing ESW through-the check valves _to verify they open and then manipulating the appropriate
                                                                        -                        a
,                             valves to reverse flow through-the check valve and measuring-leakage through.-a drain connection upstream of the check valve to verify it . has                      ,
closed.        Safety-related r SWS. check valves are               ~
verified to-close by measuring leakage.through a drain connection upstream of.the-. valve.                           ,
Components Tested:        Check Valves-                                                 !
46ESW-19A,B:           46(70)SWS-101 46ESW 20A,B           _ '4 6 (70) SWS-102 46ESW-21A,B-           46SWS-60A,B' 46ESW-22A,B            46SWS-67A,B 46SWS-68 46SWS-69 Frequency:. Monthly i
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                                                                                                         ~ ~'
l ATTACHMENT 2 I
l
: 2. Continued BT-19A, Crescent Area Unit Cooler Performance Test

== Description:==
Thermal performance of the crescent area unit coolers is measured.              Normal service water is the cooling medium for this test.
Components Tested:    66UC-22A,B,C,D,E,F,G,H,J,K                crescent area unit coolers Frequency:      Quarterly (presently the unit coolers are tested biweekly)
BT-J9B, Electric Bay Unit Cooler Performance Test *

== Description:==
The thermal performance of the electric bay unit coolers    (67UC-16A,B) is determined.                   Normal service water is the cooling medium for this test.
Components Tested:    67UC-16A,B electric bay unit coolers Frequency:   Semi-annual BT-19C, Crescent Area Unit Cooler Performance Test with ESW Flow

== Description:==
This test determines the heat removal capability of the crescent area unit coolers. Emergency Service Water is the' cooling medium for this test.
Components Tested:    66UC-22A,B,C,D,E,F,G,H,J,K crescent ~ area unit coolers Frequency:   Semi-annual ST-19D, Cable Tunnel Ventilation Cooler Performance Test *

== Description:==
This test determines the heat removal capability of the cable tunnel /switchgear room coolers.
Normal service water is the cooling medium . for this test.
Components Tested:    67E-11,14'               cable _ tunnel /switchgear room coolers Frequency:   Semi-annual Page                                                                                                           - _ _ _ _

l ATTACHMENT 2
: 2. Continued ST-19F, Crescent Area Unit Cooler Performance Verification Test *

== Description:==
This test verifies crescent area . unit cooler thermal performance using hand held monitoring-test equipment                     instead  of  the   permanently installed test equipment.
Coinponents Tested:     660C-22A,B,C,D,E,F,G,H,J,K crescent area:
unit coolers.
Frequency:   Semi-annual S7-19G. Electric Bay Unit Cooler PerformaDoe Test with ESW Flow *

== Description:==
This test determines the heat removal capability of the electric bay unit coolers.                       Emergency service water is the cooling medium for this test.
Components Tested:      670C-16A,B electric bay unit coolers Frequency:   Semi-annual-ST-19H. Cable Tunnel Ventilation Cooler > Performance Test with EH

== Description:==

This test determines the heat removal capability
                                -of    the   cable                  tunnel  ventilation   coolers.
Emergency service water is the cooling medium for this-test.
Components Tested:      67E-11, 14 cable tunnel /switchgear room coolers Frequency:   Semi-annual other   -
Heat Exchancers that are not Currently Performance Tested The following safety-related heat' exchangers are capable of being supplied by the ESW system and are not presently subject-to thermal performance testing. Other methods are used to assure their proper performance as described below.
A. Emergency     Diesel Generator Jacket Water Coolers, 1A,1B,1C and 1D.                                                       93WE-Page                                                                                              _. _

ATTACHMENT 2 These units are periodically disassembled, inspected and eddy current tested in lieu of performance testing.       The cooling medium for these units is ESW.        Operability of these heat exchangers is demonstrated by monthly operation and    surveillance    testing  of   the   Emergency   Diesel Generators. ST-8Q verifies the design basis flow rates to these units are met.
B. Control Room and Relay Room Air Handling Units,.70AHU-3A,
         -3B, -12A and -12B.
These units provide cooling for the Control Room and Relay Room areas. The cooling medium for the units is a closed loop glycol system with a service water and Emergency Service Water backup which must be manually valved in._ The development    of performance tests for these units is currently under consideration. It is undesirable to drain the glycol from the AHUs and flush lake water through them.
Presently, ST-8Q is performed to measure ESW flow to nonsafety-related control room ventilation equipment which is supplied by the same piping as the Control Room and Relay Room AHUs. Since the nonsafety-related units require a higher design basis flow rate than the safety-related units, this test verifies that adequate ESW flow to 70AHU-3A, 3B, 12A and 12B would be obtained if they were m.bnylly valved in.
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                                                                                      ,._ _ _ m _                   _.-      -
E'   ' ''                           ATTACHMENT 3 l-o New York Power l Authority 1 James A. FitzPatrick Nuclear Power Plant' As-built Crescent Area-Unit Cooler ControllConflaurationi Introduction To improve the reliability of the crescent area -. unit coolers, the                                                 j Authority- recently= completed modifications ' that; will reduce. the-                                          o potential for silt accumulation. Instead .of throttling cooling- water c flow to the coolers,. continuous cooling water flowLis supplied to thei                                         =
coils. Control-circuits:were modified to actuate-the-cooler--fans as a function of. area . temperature..         T e c h n i c a l-- S p e c i f i c a t i o n -; c h a n g e s :
associated with these' improvements were. submitted by1the; Authority,                                          1 (Reference b)'andssubsequently approved bydthe NRC as: Amendment (156f                                              ,
(Reference c).                           =
a q
A design-change, prepared-and^ approved1aftereAmendmentil56LtoLthe-Technical Specifications .had been, is'suedlbyt the ' NRC, reduced T the i                                      q number 1of coolers affected :-bylthe modification- fromi en                        t J tot eight.                  s This change was made due: co 'potentialL technicallproblemsf associated with excessive ' fan ? cycling - of thel unit - coolers.J . . To prevent? this problem-only eight of the unit cool'ars were< modified.'-The" remaining two coolers-(one in-_each crescent = area), provide cooling;as;they?did
                                                                                    ~
i'                                                                                                                                  '
originally; The service water flow rate isLstillithrottled by the TCV -
I    c but at a higher flow rate because the other eight unit: coolers provide                                         q little or noJ. cooling ~during;normalEoperating;conditionsqwhen their-fans are off. The actual TechnicalLSpecifications pagesiissued!by the?                                               '
NRC as part of Amendment 156 are unaffected by these alterations. 'The-                                         j FitzPatrick Technical specifications?are correctiand' accurate.1 !The                                              i conclusions.in the Authority's safety evaluation Jare still valid "                                             j
                -While the amended' Technical; Specifications .'pages'iss'ued by.the NRC are                                        ,
unaffacted,by these alterations,'the7 current,configurationidoes;not' 4                agree withLtheodescription included in theLAuthority'sjapplication.-
:                                      ,                                m      -
The NRC Project Manager /for FitzPatrick,xafter?being notified ofLthi's)                                        ]
                ~ change,: , asked that 'the'; Authority . submit! af description /'of: lthe' i
modifications as4they were: installed.4~ :Thecparagraphatbelow describe                                           ?
the . crescent ' area! cooler ?controliconfiguration. -                    OtherJunitVcooler,                      <
modifications, notLrelated to"thefTechnicalRSpecifications,c                                   areinote
               -described.-
41 J
               - Pre-modification- Crescent 2 Area cooler Des'li2n''
2 i
                                             ,    ,                                          24 4                                    ,
               - The.. Reactor Building Crescent ' Areas i are; cooledLby Lten: air-to-water-
               , heat exchangers'.' , These' ten ' coolers: are dividedrinto two trains. Five coolers' are installed in'each crescent area.- Air ris drawn' across the                                         A cooler'sJcoils by a motor driven fan.
0
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    .'-                              ATTACHMeny 3 Under non-accident conditions, cooling water is supplied by the Service Water System (SWS).         In the event of an accident, the Emergency Service Water (ESW) System supplies cooling water when the SWS may not be available.
Pneumatically-operated Temperature Control Valves (TCVs) installed in the supply line to each unit cooler originally throttled the flow of
;     cooling water. Ten Temperature Indicating and Control Switches (TICS, i
one per cooler) were used to sense area temperature and regulate air pressure to the TCVs as a function of area temperature.        Increased area temperature sensed by the TICS would in turn change the air pressure to the TCVs. The TCVs would open, thereby increasing flow to the cooler and lowering area temperature. On a loss of pneumatic supply, the TCVs move to their open position.
Prior to installation of this modification, the fans ran continuously during normal operating conditions. Ten control switches in the main control room could be used to turn each fan on or off.
These coolers were sized to reduce the temperature of the air in the crescent area in the event of a design basis loss-of-coolant accident (LOCA). Since heat loads in the crescent during normal plant operations are significantly lower than those t.een during a LOCA, the TCVs were essentially closed allowing little or no flow through the
,    coolers. With little or no flow through these lines, any suspended solids (such as silt) accumulated in the coolers. This condition was further aggravated by the fact that the coolers are situated at the lowest points in the SW/ESW piping.
1990 Refuelino Modifications During the 1990 refueling outage, eight of the ten coolers were modified. Two coolers were not modified and flow through those coolers are still controlled using TICS and TCVs in the supply piping.
l    For the eight modified coolers, TCVs were removed from the cooler l
supply piping.       This will allow approximately 24 gpm to flow continuously through the coils of these eight coolers.
The fan control circuitry for these eight coolers was modified so that Temperature Control Switches (TCS) turn the fans on as a function of l    area temperature.      Fans motors must be turned off (de-energized) l    manually to minimize excessive cycling of the fans and eliminate the l    need for frequent replncement of the TCS. The fan motors can also be l    started manually from the control room.
l l
l Page                                                                                  1 l

_ _ _ _    . . . _ _ _ _ _ . _      . -   -_ _ _ _ . -       . _ _ .   .._-m. .   . _ . _ ___~._ _._ _       . .
ATTACHMENT-3 l
l The TCS setpoints are staggered so that the fans are energized over a range of temperatures.               As the temperature in each crescent increases, additional fans will automatically . start.                   Within each crescent, one cooler fan will start when the temperature reaches 85 degrees F; a second fan in each crescent will start when the
                                                   ~
temperature reaches 90 degrees F; one more at 95 degrees;-and, the last at 100 degrees F. When the-air temperature exceeds 100 degrees, the four fans-in that area will have automatically started.
One cooler in each crescent continues to function using the old TICS /TCV control system.           During normal conditions, this one cooler will remove the heat generated by equipment in its area. The SWS ' flow to this cooler will still be throttled by a TCV but the flow rate'in its coils will be increased since the other four coolers will provide                       I little or no cooling.
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