ML20028H690

LER 90-025-00:on 901223,determined That Common Min Flow Path Return Line for SI Pumps to Refueling Water Storage Tank Frozen.Cause Undetermined.Need for Effective Communications Will Be Reiterated to Plant personnel.W/910122 Ltr

ML20028H690
Person / Time
Site:	Wolf Creek
Issue date:	01/22/1991
From:	Bailey J, Mike Williams WOLF CREEK NUCLEAR OPERATING CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-90-025, LER-90-25, NO-91-0021, NO-91-21, NUDOCS 9101280146
Download: ML20028H690 (9)

Text

. - . .

[f

.:. }

.- l

~

-u W4) LF NUCLEAR CREEKOPERATING John A. Badey Vce Prwdent Nucmar operai.on.

' January 22, 1991 NO 91-0021 U. S. Nuclear Regulatory Commission -

ATTN: Document Control Desk Mail Station F1-137 Washington, D...C. 20555 l

Subject:

Docket No. 50-482: Licenseo Event Report 90-025-00 f

?

Gentlemen:

The attached Licensee Event Report .(LER) is being submitted pursuant to 10 CFR 50.73(a)(2)(1)-and 10 CFR 50.73(a)(2)(v11).

-Very truly yours, John A.= Bailey Vice President.

Nuclear. Operations JAB /aem Attachment

cc t : A. T. Howell (NRC), w/a-R. D. Martin (NRC), w/a D. V. Pickett (NRC), w/a M. E. Skow (NRC), w/a

\\3 '- .

' V RO. Box 4 i t i Durington, KS 66839 / Phone: (316) 364 8831 An Equal Opporlurvty Empbyer M FMC. VET

.. .. , .- , . _ . _ . _ . _ _ . . .. . _ . , _ . . . . . . . . . .m. ,, , ,, . . - . , _ . .

N C f e9m 3a. V S~ hucttast REQULA10RY COMMI&sION A*Pf40Vf D OMB NO 3*60 0600 i

. LICENSEE EVENT REPORT (LER) m'a* 5 ' '2""

PACILif Y NAME tu DocatY NuuttR ut PAGEiJ.

Wolf Creek Generating SLation 0 l 6 l 010 l 0 l 4[8 l 2 1 lorl 01 a Doth Safety Injection Pumps Inoperable Decause Of Prozen Mirumum Recirculation Lino .

To Refuelina Water Storace Tarik (VENT Da f t 191 LE R NUMitt R 16) fitPOv1 T DAf f (Fl OTHER # AcetifitS INYOLVED tai MONTH day viAR vsAR " jjQ' , 7 ('[' y uomin Day itar r a cit. t v a. avis DOCitt f NUMet HiS>

0 151010 10 1 1 1 1l2 2l3 9 0 9l 0 0 l2 l 5 0l0 0l1 2l2 9l 1 0 1 5 10 1 0 f 0 1 ! l OPE R ATINO

"' " " " N C # A b #*** '"' * "' #'*"#' "

" ' " ' 20 *2m 20 => n"*>

1 50 n= inh->

204uei.io Ha 0 2.<.H u ee ni.H H,i umi.

0 01 -11 010 20 40si.Hiiwi 20 ao6teH1Had so 2e<.H2:

n ee.t3t.ic2ii.ai

_ gHt, gg<,,ga,A,ep,r.cr

{ 60 73<.l(2144 60 731.IQHemital .Ri641 20 40ClelH Hevt 50 73teH2ilell 6013i.it2 tivi.eHei 20 4064.H1Hul 60.7heH20 teed 50 73 aH2Hal LICENSit CONTACT #0R THl3 LER H21 NAME TE LEPHONE NUM9tR AH6 A C004 Merlin G. Williams - Manager Plant Support 3 lill 6 3;6l4; i 8l8 l3 1 1 COMPttTE ONE LINC FOR t ACH COMPONINT P A.lLURE OfSCRI$tO IN THfS REPORT 1131 CAUSE SYll t M COMPONINT ]jhC. nt'

's TO NPR CAust $vs7tM COMPONENT N) M'[,I,#$I y

X FID TISI I Ul0 I715 N I I I I I I I I I I I I I i i I I i l i I SUPPLEAINT AL REPOftt EXPECTIO (141 MONTH DAv YtAR

$U6MrsitON vii119 yes, torn #.,e EHECTRO SU6VISSION DATEI NO Ql g Q lg gl }

u,,,,AC,u_,R,.......,,,~,._..,_..,n.,

-On Decm ber 23,1990 at 1230 CST, it was determined that the common minimum flow path return line for Safety Injection (SI) punps PEM01A and PEM01B to the Refueling Water Storage Tank (RWST) was frozen. Previous actions to investigate probl ms with the freeze protection system were unsuccessful in preventing devokpment of this condition. The two SI pumps were declared inoperable with unis return line frozen ard entry was made into Technical Specification 3.0.3. The pumps were returned to operable status at 1757 CST.

A faulty Ambient 'Iunperatttre Switch for the RWST heat trace system prevented the heat trace frun ac.r'veting and was subsequently replaced. In addition,.

administrative controis d d not cufficiently recognize the safety significance of flow e Agt this line and the need to ensure flow capability. kiditional - ti. dance has been provided. .Also, ineffective cmmunications between Opections personnel and Elect.rical Maintenance personnel prevented thorough evaluation of the RWST heat trace trouble alarm. The need for effect; /e ccxmunications will be reiterated to plant persornel.

l l

l l

Ie sJi

M C # DR M WQ 11$ NVCL E A R M f Gut A T UR T COMMIM40N i . ,,,u s m, LICENSEE EVENT REPORT (LERI M,'h*^,',',%';T;'R'," "'ENX,"'ufll'LV a'" ',',0 TEXT CONTINUATlON TC%",'4",'d'i?n?Mf'A15c ,'"^" 3 ',f l,"l 0'f"1

^

?.'f"J.','OMi"OW,VN .W?V,0N, DC 70501WO t't?R Of MAN AGI M( N f AND SVDO( f, Vr A$HrNG f QC,L117 N AM4 (19 Mht N W illR Up gg p gyggg g ggp pgGg lp

• saa " M.W. 'M Q Wolf Creek Generating Station 0 [5 l o l o j o l 4 l_8[ 2 91 0 -

0 l .15 -

O l 0 012 W 0 18 in a <-~, n.w .-.-.ax ,- m ,m n IWHUACPKN On Dec mber 23,1990 at 1230 CST, it was deteuntned that the cmnon mininum flow path return line (i.e., recirculation line) for Safety Injection (SI) pumps [IQ-P] PEM01A and Pm01B to the Refueling Water Storage Tank (RWST)

[BP-TK] was frozen. Since a recirculation flow path mus*, be present to prevent pump dannge during extended SI pump operation when the Reactor Coolant System (AB] pmssure is above the shutoff head of the pumps the two SI pumps were declared inoperable. Ubchnical Specific.ation 3.5.2 requires that two independent Emergency Core Cooling Systm (FCCS) subsystems be operable and pmvides actions in the event that one OCCS subsyst m is inoperable. The simultaneous inoperability of both SI pumps placed the plant in a condition prohibited by the plant's Technical Specifications and msulted in an entry into Technical Specification 3,0.3. %emfom, this condition is being reported pursuant to 10 CFR 53.73(a)(2)(1). It is also considered reportable under 10 CFR 50.73(a)(2)(vii) as a single condition which caused two independent trains to became inoperable in a single system.

DESCRIPPION OF IMNP The Control Rom received freeze protectir;n trouble alarms for the Dantneralized Water Storage Tank [KC-TK) and the Condensate Storage Tank

[KA-TK) on December 20 and 21, 1990. Cratrol Rom Annunciator ALR 55F, "Preeze Protection Trouble", is illumirated when the temperature of the tank's heat traced piplug falls below a nminal 35 degrees Fahrenheit. The Freeze Protection Panel breakers were verified to be closed per Alarm Response procedum AIR 00-055F. Fo)10 wing discussions between Control Rom personnel and Electrical Maintenanca personnel the current flow in the heat trace was varified for the affected circuits to confirm proper operation.

On Decmber 21,1990 at 2045 CST, the Control Rom received a freeze protection trouble alann for tha RWST. Discussions were held with Electrical Maintenance cancernmg the capabilities of the heat trace alarms. Contml Rom personnel were unaware that a crew change had occurred within the Electrical Maintenance organization since their last discussions concerning troubleshooting of the freeze protection system. Consequently Control Rom personnel were not explicit in their request for current nuasurments and the convursation was instead focused on the "reflash" capabilities of the alam. It was concluded that if an alarm on the heat trace circuit were in a " locked in" condition and a breaker feeding the heat trace were to trip, a ' reflash" would not occur on the locked in alarm. l 2herefore, Operations personnel then began to check the circuit breakers l approximately every /.our hours to ensure that the heat trace circuits were I operating properly /.or all outside tanks.

NnC f e.m 364A team

C FORM Jh6A US NUCLE AR PEGULATOPY COMMt590N

. E KelHES 4'3092

. LICENSEE EVENT REPORT (LER) 'd,'g^y??o=M'raan 'JiJi,'%cj"Ol,*&UM TEXT CONTINUATION 10"l,7Alll,"llOj M, ',*,RP,"^,,'#f ',"l "'f"n

.PA 6RWO fE> J (3 0 'O IC 08 M AN AGt ME NT AND SUDGt T. W ASHING T ON. DC 20$0 )

f ACILif V NAMk p, DOCR L i NUMBE R U L E R NUM64 R 161 P AGE 13'

'f

• EA* " %#* (^ b Jy Wolf Creek Generating Station rm m - .., . . . w e,- m .,nn o p ( 0 l 0Hl 4 l8 l 2 9 l0 -

0l2l5 -

0[ 0 0l3 of 0l 8 on December 23,1990 at 0007 CST, an attmpt ms nede to add water to the RWST because of a low leve] alarm. The level was substantially above the required 7bchnical Specification minimum level. The flow path involved the return line to the RWST, which also provides a flow path for Safety Injection pump recirculation flow (Figun 1). When this attempt to fill the RWST failed, an investigation was started to detemine the cause. It was learned that an open work request existed to repair Isolation Valve BGV0195 (CB-ISV). This valve isolates the Chemical and Volume Control System (CB) frm the Refueling Water Storage System [BP) . The proble description on the work request indicated that the valve st a and diaphragm had separated.

Believing that this conciition would provent flow through the valve, the faulty isolation valve was identified as the reason that flow could not be established to the RWST. Because RWST level was still substantially above minimum level, it was decided at that tire to wait until dayshift to have the probl e with Isolation Valve BGV0195 further evaluated. During the Shift Turnover, this event was discussed as well as the need to confirm proper operation of fmeze protection circuits.

The dayshift crew proceeded with the investigation of the items that were discussed during the Shift Turnover. It was decided to try to fill the RWST using an alternate flow path and to have Electrical Maintenance verify the operation of the heat trace circuits. At 1139 CST the dayshift crew atts pted to fill the RWST through an alternate flow path, which did not require flow through Isolation Valve BGV0195, utilizing Fuel Pool Cleanup Pumps (DA-P) PEC02A and PECO28. At 1145 CST, Electrical Maintenance determined that the heat tracing on the RWST return line had a faulty ambient tmperature switch and no current existed in the heat tracing.

Af ter the attmpt to fill the RWST through the alternate flow path failed, the RWST return line was determined to be frozen and therefore unable to fulfill its function as a recirculation line for both SI pumps. A recirculation flow path must be present to prevent pump danage during extended SI pump operation when the Re ctor Coolant Systm (AB] pressure is above the shutoff head of the pumps. At 1230 CST both SI pumps were declared inoperable and 7bchnical Specification 3.0.3 was entered.

Both SI pumps were placed in " pull-to-lock" at 1250 CST to prevent an autmatic start and subsequent damage because of a potential shutoff head corxittion. The Shift Supervisor assigned an operator to operate the SI pumps under appropriate circumstances.

NMC Feem M4A 468P l

'. g,,'o.. m '

u. ucu..a.ouu.o ,co ..o~ ,,,,, ,,, _ _

e,,,nu am ISs"^u'A80f"Pj"s"o"'ni?",j'31'LCf7W ,*o'".'J$

. LICENSEE EVENT HEPORT (LER) "

TEXT CONTINUATION  %""'"dln';' C'u'A M fJ0E'" ic',7 ^,'!df ["s' "Wi f,i

'A'MA4%2","#3%"~^m"?!?WTA 0?l?

OF M AN AGE ME N f AND BUDGE f, WA$NING TON. DC 70503

, Acets f y Naut til DOCKi t NUMBE R M' ((R NUMbE R I6I PAGA(Ji

'saa " S.'# TQ Wolf Creek Generating StaLion 0 ls l0 l0 l0 l4 l8 l 2 9l0 -

0l2l5 -

0 10 0l 4 0F Ol_8 re nt ,, - - . - ,, .- m,c ,- m Activities were initiated to thaw the RWST return line in order to obtain the use of the SI pump's recirculation line. A jumper was installed across the inoperable Ambient 1bmperature Switch to provide power to the heat trace. A temporary heat source was also used on the frozen section of the pipe. In conjunction with the external heat being applied, the Fuel Pool Cleanup Pumps were used to provide internal pressure to the blockage. .At 1600 CST, the plant declared a Notification of Unusual Event and began to reduce power to cmply with Technical Specification 3.0.3.

Flow was established to the RWST frm the Fuel Pool Cleanup Pumps at 1702 CST. Reactor pcuer was stabilized at approximately 65 percent while verifying SI pump recirculation flow. Recirculation flow for SI pump PaiOlA was verified at 1735 CST per surveillance e.vculare STS DI-100A and Technical Specifications 3.0.3 was exited. 'Ibchnical Specification 3.5.2 was then entered for having one ECCS subsyst s inoperable and the Notification of Unusual Event was terminated. Following the verification of recirculation for SI pump PEM01B at 1757 CST per surveillance procedure STS EM-100B, the RWST was placed in continuous recirculation through its return line to assure minimum flow capability and 'Ibchnical Specification 3.5.2 was exited. At 2235 CST, Reactor pomr was restored to 100 pm.cuit. Electrical Maintenance was also instructed to verify the current flow in all heat trace circuits every four hours to confirm proper operation. A review was conducted to detenrine if there were other similar pump arrangments in which a heat traced line could freeze and prevent recirculation capabilities of the punp and none were found. A new Ambient Temperature Switch.was subsequently installed to replace the temporary jumper at 1340 CST on Decmber 24, 1990.

HOOT CAUSE AND ONRICPIVE ACTIGE

'Ihere are several factors that led to the freezing of the RWST return line which also serves as the recirculation line for both SI pumps. A faulty ambient tmperature switch for the RWST heat trace systs prevented the heat trace frm activating when the external tmperature dropped below 40 degrees >

Fahrenheit. Althcugh the exact cause of the failure could not be determined, corrosion of the internal mechanism is thought to be a najor contributor. In order to ensure proper operation of the Ambient Tuuruuture Switches and the low 'Iwnperature Alarm Switches, they will be calibrated in the fall cf each year to ensure that the heat trace circuits and alarms are activated at the proper tmperature.

- NRC f eem Je4A 164H

C FORM 366A U 4 NUCLE AR RIGutaTORY COMMISSION E ,..nn mn LICENSEE EVENT REPORT (LER) 'Jg'MjRo"J'g&"'23"}i/ M*'A' ,*o'n",'"'j TEXT CONTINUATION %l"4",7 "! ^,, Z"Gj 'J"?',MC 5"^4'M"l "MfA PA E WO RfD 11'ON J O IC Of MAN AGE AAE NT AN() 6uoGE T, W A$HING TON DC TJ603 FCCitlTV 4AME m DOCKt Y NUMst n in LER NUM8ER foi FAGE13) n=* "WP )*W Wolf Creek Generating Station 0 jf 10 l 0 l 0 l 4 l8 l 2 s 9[0 -

0l2l 5 -

0J 0 015 OF 0h TEXi W awre apare a reeweed, use smoorund MC Form Jti6 Cat (IM In addition, administrative controls did not sufficiently recognize the safety significance of flow through this line and the need to ensure flow capability. This Licensee Event Report will be incitded in Operations Required Reading to ensure that all licensed personnel are cognizant of the details of this event. Also, additional training will be provided as part of licensed requalification training to licensed personnel reiterating the safety significance for flow through the line and enphasizing that immdiate operator actions are necessary when freeze protection alanns are received.

This additiona] training will be completed by March 29, 1991. The subject will also be included in the recurring training file to be evtluated for inclusion in subsequent requalification training cycles.

Also, ineffective comunications between Operations personnel ard Electrical Maintenance personnel prevented the RWST heat tracing fran bel,g thoroughly evaluated when its alarm was received. Control Roan personnel were unaware that a crew change had occurred within the Electrical Maintenance organization since their last discussions concerning troubleshooting of the freeze protection systen. Consequently Control Room personnel were not explicit in their request for current neasurenents and the conversation was instead focused on the "reflash" capabilities of the alarm. The need for effective comunications will be discussed in group meetings for Operations, Maintenance and Instrumentation and Controls personnel. This subject will also bo included in the requalification training mentioned above for licenad personnel. These caninunication needs will also be reiterated to plant personnel through the next newsletter fran the Director Plant Operations.

Alarm Response procedure ALR 00-055F, " Freeze Protection Trouble",

instructed the operators to verify that the pomr supply breaker, the heater circuit breakers, and the control circuit breaker for tha affected Freeze Protection Panel are closed. The heat trace citruits were believed to be operational when the circuit breakers were closed. This procedure has been revised to provide nore concise instructions when a freeze protection  ;

trouble alarm is received in the Control Roau. These instructions include a provision to have Electrical Maintenance check heat trace current flow daily to verify proper operation when a freeze protection trouble alarm is activated. Also, this procedure instructs the operators to place the RWST on recirculation if tenperature control cannot be restored. Procedure STN GP-001, " Plant Winterization", has been revised to include provisions to put i the RWST in continuous recirculation through its return line to assure l minimum flow capability of the SI pump recitutlation line. Design  !

enhancanents and other procedural enhancements att being examined at this i time and if any are deened necessary they will be discussed in a l supplemnt to this report that will be subnitted by February 28, 1991. l 1

)

.,.c ,- man \

l l l

NAC Of M 3e4A U S. NUCLE AR mt 0VL A1Dn v COMMs55104 E xPIRES 4!3C/92

. LICENSEE EVENT REPORT (LER) fd,'s"^4','?A"MEM",005;M*j',/ .g"Tn? ,*o'n" ',"

TEXT CONTINUATION i;%",lM'."/s ^1T!",iMF8"l'/c'."^,l!E!"' 0'l ,"f!

"lJ"I.^ls00'?"n"c520 '05c?'h &$fd 0?O-OF MAN AGEMEP J T AND luDGET.WASHINGlON.DC 70$03 PACILIIY NAME fil DOC K t I NUMe t R U p LtR NUMBE R i$t FAGE (3) naa "$?J. -

%*.O Wolf Creek Generating Station 0 [5 lo l0 lo l 4l8 l 2 9l 0 -

0l2l5 -

Of 0 0 l6 OF 0l 8 n n - .,,.a. m , - ci n ..,,m N]DITIONAL INKIDWPIN At the tim of the event, the plant was in Mode 1, Power Operation, at approximately 100 percent Reactor power. Power was reduced to appmximtely 65 percent before subsequently returning to 100 percent Reactor power.

he faulty Ambient 'Ibuperature Switch was manufactured by United Electric Company, Model Number AMC-1A.

%ere have been no previous similar occurrences.

SA?mY SIGNIFICMCE OF EVMff

%e functional requirenants of the safety injection pumps to mitigate the consequences of design basis accidents (DBAs) were reviewed and the Updated Safety Analysis Report (USAR) licensing basis analyses were evaluated to assess the impact of the frozen recirculation line. Specifically, the analyses associated with the por '11ated primary and secondarv system pipe ruptures were examined because tne Dnergency Core Cooling Syitem flow is necessary to mitigate the consequences of these events. %e following sections sunmarize the evaluations performd for the affected safety analyses.

Secondary System Pipe Rupture Events No credit has been taken in the analysis of these secondary systen pipe break events in the USAR-for the operation of the intamdiate head safety injection pumps. % erefore, potential SI pump damage, because of deadheading situations, resulting frca the frozen recirculation flow pipe has no impact on the analysis results calculated for the Feedline Break and Steamline Break events.

Primary Systen Pipe Rupture Events Steam Generator Tube Rupture (SGIR):

Ibr the analyzed SGIR scenarios, a deadheading situation may exist for a long tine period, which in turn may potentially result in SI pump damage and reduction of total SI flow. However, use of tha maximum attainable SI flow rates in the analysis is conservative. Maximizing the SI flow leads to maintaining a higher primary to secorriary pressure differential and i consequently a higher brmk flow rate for a longer time period. %erefore, l

SI pump damage caused by a deadheading condition during a postulated SGIR ,

event would result in less severe consequences with respect to the offsite  !

dose releases and the margin to overfill, l l

1 1

Nac p mA toe 9 l l

. . - - - . . , . . , . - - - . _ - . - . . . . . - ~ - _ - ,

1.

L, .

NJtC POEM 384A U S. NUCLE AR REGUL ATORY COMM:SitON j._ ,

t uttAES 4?)092 1 L LlCENSEE EVENT REPORT (LER) ',8.'l"n*,7llo'd8R 'c'",o a5'n'dNj',,' ,o c, "l,t,' ,*o'n",'A"'j TEXT CONTINUATION A% "n',"45"4n MAf d ,'ig f M 'C'"^g

, V,5 "'f,"f;i l P FE WO ME ION O 50 0 OF MANAGEME NT AND SUDGE T,WA$HINGTON. DC 20503 F ACILt!Y NAMt III DOCK t i NUMBE H 121 LE R NUMDE R (6) PA04 (31 VEAR SE EN iAt : . aEve h l Wolf Creek Generating Station o;5;o;o;oj 48;2g 90 _

0l2l 5 _

0;O 0l7 or 0l 8 i un y ,,,,,,, N.-. . - . .- we ,-m m j Iarge Break loss of Coolant Accident (IOCA):

Daadheading conditions will not exist for the SI pumps during the blowdcun phase of the large bmak IOCA as the Reactor Coolant Systm (RCS) will depressurize to the SI pump discharge pressure over a very short tine

period. % erefore, the frozen recirculation flow line of the SI pumps would-not result in pump damage should a-large break IOCA have occurred during that tine period. For these resons, the frozen pipe would not adversely affect the calculated peak cladding tmperat.are (PCT) for a postulated large break IOCA.

l Small areak IOCA:

l ne review of the currently analyzed break sizes for Wolf Creek Generating l Station concluded that the deadheading conditions would not exist for sufficient duration to damage the SI pumps should a break in the range of a -

3 to 6 inch line occur.

i.

An evaluation is being perfornud for a small break IOCA with a range of line sizes frm 3/8 to 3 inches. Preliminary results of this evaluation inci'cate I

that the PCP is not limiting and boron precipitation is not a concern for i

those breaks where the SI pumps are postulated to be unavailable because of the potential damage caused by a deadheading situation. Final results of this evaluation will be included in a supplenent to this report that will be

subnitted by February 28, 1991.

l Based on the above review, this event did not significantly jeopuxlize safe operation of the plant nor pose a threat to the health ard safety. of the public.

l NRC Form 384A lH95 ,

I i

f o NuctiA. ..culA,0. ,co - ss.oM

e ,o M-A ,,,,,,,,,,,,,,,,,,,,,,

.....4-8 c LlCENSEE EVENT REPORT (LER) lsls"^,'L90,,q[?,[',".,"'J37,l's,'io 5

';V ,*o'" '35 TEXT CONTINUATlON fl,"*4*'5,';'ii',"f'M,*/l"?',7,15y,"",",',P LT ".$n't fA DC 7(Pe% AND FO HE THEGUL P APEA f NWOH DR V COVMtS$f04 W ASHING A HE DUCT k)Pe FMQJ6 C tO,01$0 N 0 604) O' F tC E Of MAN AG(Mi NT AND ilVOGE I. W ASHING tDN. DC M4.1 f QCILif V NAML lit DOCR t f NUMRt. LJ) L E. htAtef R 161 PAGE ila vEA4 ** ('(,*

, , k ({,yS[,')

Wolf Creek Generating Station o ls lo lo lo l4 l8l 2 9l 0 -

0l2 l 5 -

0l0 0} 80F 0l8

,,,,,,_._...-.._N,._m.,,,m i

l SI Recirculation Line l

Safety injection Pumps l

l > s e

i l Frozen Area #) # N 4w >

7s i RWST L .-y:-

N. v '

4 y  ; muvmoor,

><}- Pipe Tunnel DGV0195 A A

".. H antaeg From Boric Acid Blonding Too A Ancher B

From Fuel Pool Cleanup Pumps

> Cms l Bcundary l

l' l

FIGURE 1 i

N.C Ferie M6A (6 6 h

._. . _ . _ _ . . .