ML20236C396

Marked-up Rev 0 to Safety Evaluation Re Proposed Direct Torus Vent to Main Stack

ML20236C396
Person / Time
Site:	Pilgrim
Issue date:	05/15/1987
From:	Mileris G BOSTON EDISON CO.
To:
Shared Package
ML20236C394	List: ML20236C391 ML20236C396
References
FOIA-87-643 2144, 2144-R, 2144-R00, NUDOCS 8710270144
Download: ML20236C396 (30)

Text

{{#Wiki_filter:htE Proposed Change-Safety Evaluation No.:

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REV. O SHEET l OT // PILCRIM NUCLEAR P N ER STATION Rev. No. PDC PCM Systee Calc. Date:kJ5fd9 Initiator: Dent: Group: No.: Name: No : G. V. Mileris NED FSMC 86-51 Direct Torus Vent Provide a direct torus Description of Pronesed change,in stacktest or exp(eriment: venE to the ma DTVS) SAFETY EVALUATION CONCLUSIOlt$: The proposed change, test or esperiment: 1. (X) Does Not ( ) Does increase the probability of occurrence or consequences of an accident or malfunction of equipment taportant to

• safety previously evaluated in the FSAR.

2. f) Does Not ( ) Doe's create the possibility for accident or malfunction of a different type than any evaluated previously in the FSAR. 3.

6) Does Not ( ) Does reduce the margin of safety as defined in the basis for any technical specification.

RASIS FOR SAFETY EVAlt1ATION 0110L0$1(18S: SEE ATTACHED SHEETS Gange Q ange N Recommended ( ) Not Recommended Date M M 7 SE Performed by Exhibit 3.07-A ~ " f,,. # Sheet 1 of 3 155UCy y.Q, s C 4 5 " w" ~, *\\n.u, 3.07-13 Rev. 4 8710270144 871022 PDR FOIA SORGIB7-463 PDR

S&7e Q Leaseation SAFETY EV4tt1ATION PILCRIN NutttAR PCkER STATICM fNGF r~ A o f / / Rev. No.o q A. APPROVAL This proposed change _ involve a change in the Tec,hnical Specifications. ~ This proposed change, test or experiment does ( ) does not. 0d involve an unreviewed safety question as defined in 10CFR, Part 50.5f(a)(3). / This proposed change involves a ch e to the FSAR per 10CFR 50.71(e) and is portable und R50.5 Use o the vent eyond e scope of this safety Comments:.. evaluation and will be covered in the emergency operating procedures. A separate safety evaluation I will be written to cover use of the vent. 1 The safety evaluttien basis and c leston is: Waf91 \\ Q Approvd not ed l SAsle7 b & h-(11th e sci,u ne scoop teuerio.te so,,ortini oiscipne stov, teuerente ( REYitM APPROVAL N N^ ~ Comments: DTis. ht ret Ms u se, tlers m+ om. sse s.eru.nd s 'f h, % & eC % bivs wo+- ke nDnsu A ks. & Me. Li w% $L 0+4s s*!Jhlt? $)YY<% uM~ M i i d l" A8 * - ce' b 'a 4 ik "5ciM" Nl ()6 Gro@ Leadet/Date assessd 4 & cmse - ih '{

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'So la 3 N j C'. etc RtvitM SG s Ac bTv5 as4., ( ) This proposed change involves an onreviewed safety question and a request for authorintion of this chan e must Le filed with the Directorate of Licensing BRC prior. implementation. (d ni. gro,osed aan.e oes -t invoive..revieww e.fet, o,e$?$ AMIaY~~~ Ain mee ore m etin, u a.r ')-r/ .. l \\$$dE) b CONSTRgAc ON'Ja cc: r hinit 3.on Sheet

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3.07-14 Rev. 4

SATI"Y IVAI.'.*A!!CN NO. W ? REV. NO.0SHIET3OFn . A. _OISCRIPT;0N 07 PF.0POSID CHANGE This modihcatien p:ovides a direct vent path from the torus to the main stack bypassing the Standby Gas Treatment System (SGTS) equipment on the torus purge exhaust line. The bypass is an't" line whose upstream end is connected to the gipe between primary containment isolation valves A0-5042A&B (on 8 portion of 20" torus purge exhaust line to SGT8). The downstrema and of the bypass is connected to the 20" main stack line downstream of 8078 valves A0N-108 and A0N-112. An 8" butterfly valve (AO-5025), i which can be remotely o erated from the main control roca, is-added downstream of 8 ' va ve A0-50425. This valve acts as the primary containment outboard isolation valve for the direct torus l vent line. The new pipe is ASME III class 2 up to and inclusive g l' "N* ^$$ *h : id M!!$N?#!!!EWill.is.h. 4 )x l &5 k m s+rso m e4 no -sess'. ars. prov1ED opsM e4 AC solenoid The proposed modification replaces the existing (powered from for A0-5042B with a DC solenoid valve valve essential 125 volt DC) to ensure operability during a station I blackout. The new isolatio valv 0-5025, is also provided with a DC solenoid powered from 125 volt DC ocurce. M 4 Both of these valves' fail closed. One inch nitrogen lines are added to provide backup nitrogen to valves A0-5042B and A0-5025. The present logic of A0-5042B is being modified to override containment isolation signals by keylock remote manual action., New valve A0-5025 closes on containment isolation signals but is override control logic as A0-provided with the same isolationand 5042B are in the containment isolation 5042B. When 5025 bypass mode a separate logic has baan..added to isolate both in the Torus vapot high radiadiin~)evelbd C adeoiiplit e4 ) valves if there is a overrits is Dal space. This high' radiation keylock remote manual action. 4, gg@ A 20" pipe will replace the e9 " L, 2; u s ever aucti ~ between SGTS valves A0N-108, A0N-112 and the existing 20" pipe to the main stack. The existing 20" diameter duct downstream of A0-5042A is shortened to allow fitup of the new vent line branch connection. A rupture disk will be included in the 8" piping downstream of valve A0-5025. The rupture disk will provide a second3 leakage barrier. The rupture disk is designed to open at a pressure below' direct venting pressure, but 'will remain intact during 4 normal operating conditions. This safety Evaluation demonstrates that plant safety during normal design basis operation is not degraded by the installation *S of the direct torus vent. Vent operation is not ad r pg by tha 0,,1<els art snumy& so 1%f %< vslits wlIl ow+[reakk So- <t.%Lt Ysivas a ee. se&<f)u *.M a.ch. G isoladim $pis ress1 u>s'Lat-o h r<< u t e q Ie. A ulu x both vs\\ver. s %.ah9

SAFETY EVALUATION NO.2 W s REV. NO. O SHEET g OF g safety evaluation but will be addressed by -another safety Evaluation in conjunction with the Energency operating Procedures. Although this safety evaluation does not address the vent description of the venting operation and logic of l operation, a the installed modification is provided below for information. l The purpose of the vent is to relieve excess containment ressure and prevent catestrephic containment failure as directed ~ p:ry the Emergency Operating procedures. Use of the vent will be management adxtinastrative control and would require that under the keyltek switches for operation of the A0-50425 and A0-5025 valves be placed in the Emergency Open Position to override the containment isolation signal which would be present if the l was at high pressure. Prior to opening the vent containment valves the 830T system would have to be shutdown and valves AON-108 and AON-112(the outlet of SBGT)placed in a closed fosition, M Ao- 0H B and If there is high radiation in the torus vapor spaceThatisolation signal can be overr4dden b g A0-5025 will reisolate.

get o k-sa=;ual keylock actuated switches if vamtink,1p, y.centinue.uw tx

5. PURPOSE OF THE CHANGE

! CONSTRUCTION This modification will provide t b hility te sof_Issa of the severe accident concerns by direct venting of the torus to prevent-primary containment over-pressurization during an extended station blackout. If use can be justified this ' ~ modification opens a direct exhaust path from the torus vapor space to main stack. 4 C. SYSTEMS, SUBSYSTEMS,COMPONENTi{AFFECTED This modification affeets> the containment Atmospheric control System in the following manner: The torus purge exhaust linel inboard isolation valve A0- $042B and the associated o' pipe are the components of the CAC8 affected by this psipposed modification. With incorporation of the subject modification, the CACS Will depend on both essential AC (for valve A0-5042A) and essential DC (for A0-50425) to perform itsgn gn. p 8" torus vent line will be connected to ex sting 8" i The new CACS piping between valves AD-5042B and A0-5042A. g This modification nffects the Atandby Gas Treatment System in the following manner:

SAFETY EVA!.UATION No.2I4i p REV. NO. 0 SMEET 6 0F,jf SGTS fan outlet valves (AON-108 & AON-112), ductdork from f these valves to the-20" line leading to the. main stack, and the 20", line leading to main stack are the. components of { this system affected by the proposed modification. Valve A0N-108 is. norma 11y clesed, fall-open. Valve A0N-112 1 will be revised to be normally closed, fail-closed,.and these valves will be.provided with essential DC power and local safety related nitrogen supplies (Ref. PDC 86-70). ] This modification affects the Primary Containment Isolation system (PCIS)-in the following manner: This system is affected by the modification to containment isolation valve A0-5042B logic. The addition of containment 4 outboard isolation valve (AO-5025) 'and associated controls will also affect the PCIS. l D. SAFETY FUNCTI0tt OF AFFECTED SYSTEM / COMPONENTS Containment Atmospheric Control system This system has the safety function of obviating the possibility of. an energy .I8 lease..within the primary following a %egrdok.rgactionQpre Jst.andbyi. cool Eng c^0xygen containment from a Hydroger postulated 1,0cA combined with e ' " " " * ~' ! CONSTRU.CTION 8tandby Gas Treatment System This system filters exhaust air from the reactor building and discharges the processed air to the main stack. The system filters particulate and iodines.from the air stream I in order to reduce the level of airborne contamination the environs via the main stack. The SGTS can released to. also filter exhaust air from the drywell and the suppression pool. Primary Containment Isolation System This system.has the safety. function of providing timely and consequences of accidents protection against the onset-release of radioactive materials from . involving. rhe._ gross the primary containment by initiating automatic isolation.of appropriate pipelines which penetrate the primary containment whenever monitored variables exceed pre-selected operational limits. Pr. m 1 f u % d h b W The primary containment system, in conjunction with other safeguard features, limits the release of fission products in the event of a postulated design basis accident so that offsite doses do not exceed the guideline values of 10CFR100.

1 s' SAFETY EVALUATION NO 28 % REV. NO. O SHEET g OF g E. EFFECTS ON SAFETY FUNCTION Containment Atmospheric Control System and' Standby Gas Treatment System, an0 Primary Containment Isolation Bysten " The modification changes the solenoid A0-5042B control from AC to DC enabling it to open (from its normally closed position) when required even during extended station blackout. Ductwork at the cutlet of the 83GT system is replaced with pipe and the new vent line is connected to the 20" line at the outlet of the 830T system. a Addition of a new 8" vent line with containment isolation valve A0-5025 off the torus purge and vent line results in a flow path that could vent the containment directly to the stack bypassing the eBoT system during nonnal plant operation. New logic is being added that allows override of the containment isolation signal on existing valve A0-50423 and provides the same logic for valve A0-5025. This could allow venting of the containment directly to the stack bypassing 8BGT or subjectiFg--the SBGT s to high { lS$y{}ystem containment pressure. gg l \\ F. ANALYSIS OF EFFECTS ON 8AFETY FW@ff089f$fa) sun ~lON { t --o ia o An analysis of the effects on safety siumi.4wn. -S, SGTs, and. PCI8 systems for the installation of the direct torus vent is described as foll Ws: The' change from At to DC control on A0-50423 does not adversely affect its ability to o AO-50425 when be containment is be.ing purged, or iseWre_ pen vwA.u.stes M e M.y The modificatA>.as to the ductwork and 20" line leading to the main ste a do not affect the safety function of any of the safety related systems. During normal plant. operation, the CAC8 and the 8GT8 do not use the torus 20" purge and vent line to. perform their safety functions. ~The containment isolation valves are in their normally closed

position, satisfying the safety function of the PCIS.

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[ SAFETY EVALUATION No. 2 44 RIV. No. 0 SHEET 7 OFZ (nw-excpq C<mO~.%& W During plant startup and shutdown"when the purge and vent line is in use, the logic does not allow A0-Ib2.s' to open M unless S&f2 S is closed. In addition a rupture disc W l downstream of valve A0-5025 will provide a second positive' means of-preventing leakage and prevent the stack in theevent of a single failure ofdirect release up A0-5025 during containment purge and vent at plant startup or shutdown. During containment high pressure conditions, the CAC8 does not use the torus main exhaust line to communicate to the SGT8 for performing its safety function. The existing CAC8 logic cannot override the containment isolation signal and open valves A0-5042A, ett A single failure of A0-50423 logie M would still protect the BBGT from high pressure because A0-5042A, and A0-5025 would still be closed. Valve A0-5025 and the rupture disk downstream would also prevent any inadvertent discharge up the stack. G.

SUMMARY

The installation of the Direct Torus Vent (DTV8) does not affect the safety functions of the CACs, 50Ts, and PCIs systems, or any other safety-related systems. This safety evaluation does not provide justification for use of the DTV8. The installation of this modification does require a Technical specification Change. The installation of this modification does not involve an unreviewed safety question. ISSUE 3r$4 CONSTRUCTION i

SHEETjf Or // Safety Evaluation No.: 2.i44 SAFETY EVALUATION WMtK SHEET Rev. No. O A. Systee Structure Component Failurs and Consequence Analyses. Systee Structure h onent Failure Modes Effects of Failurt Commen'ts SEE ATTACHED SHEET 1. 2. 3. j i 1 General Reference Material Review FSAR CALCULATIONS REQlLATORY SECTION PNPS TECHNICAL SPECS. DESIGN SPECS PROCEDURES GLilDES STANDARDS SEE ATTACHED SEEET l s t~ t* ) p~ s i v v ;., s. ;.h e n s., e c r. 3.. '......,mm, gy T w 1 ius u, a IVW For the proposed hardware chanfle, identify the failure modes that' are B. likely for the components. cons' stent with FSAR assumptions. For each failure mode, show the consequences to the system, structures or related Especially show how the failure (s) affects the assigned components. safety basis (FSAR Text for each systes) or plant safety functions FSAR Chapter 14 and Appendtx G). Date N Prepared by NOTE: It is a requirement to include this work sheet with the Safety Evaluation. Exhibit 3.07-C 3.07-18 Rev. 4 l l

.t SAFETY EVALtJATION No. Il## REV. No. 0 SHEET 9 OF /f SAFETY EVALUATION WORY~3 REFT l I' Syst em/6tructure/(.omponent : Isolation Valve A0- 5025. i l Failure Modes Faihure to close/F41

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Errects of Failures Bypassing of Standby Gas Treatment System; Loss of containment Isolation comments: lE Valve position indication is provided in the main l control room. Rupture disk provides protection. Failure Mode: Excessive Leakage Egrects of Failure: Release of Radioactive material above allowable. l Comments: Periodic LLRT performed to ensure leak tightness. Rupture disk provides protection. (Rupture disc is tested periodically) system /8tructure/ Component: Direct Torus vent System piping. Failure Mode: Structural tailure. Effects.of Tailures Loss of containment integrity and SGT8 inoperable. Comments Qualify piping' for design basis temperature and pressure to ASME III and 331.:.. System / structure / Component: ' Primary Containment Isolation System. Failure Moder Logic failure. No effect. Efracts or Failure: Recuncant trains of logic am)(vg/w<. dl4 k, M Comments: y ISSU D n CO N STi'...a iU-[ c ___a. I l l 1

( l' 9 I Safety Evaluation No. 214'y Rev. No. 0 Sheet oofft f SAFETY EVALUATION WORKSHEET i FSAR CALCULATIONS /PNPS REGULATORY DESIGN GUIDES / STANDARDS SECTION TECHNICAL SPECS. SPECS / PROCEDURES CODES i i 5.2 3.7/4.7 . Spec. SM-34 10CFR50 Spec. M300 NUREG CR-624 l 5.3 Spec. M600 NUREG BMI-139, Vol 1 Spec. M301 i 5.4 Spec. M600 NUREG 8MI-139, Vol 1 Spec. M-611 NUREG 0700 i 7.3 Specs. 17322-M SAM-16 ASME B&PV Code Sections 10.11 17322-M-SAM 12 III & XI Table 7.31 Specs M-603, M303 Appendix G Spec. E-347 R. G. 1.26 R. G. 1.97 Appendix 0 Spec. E-347 A IEEE-79 IEEE-23 IEEE-44 ANSI B31.1 l Calculation Number i Teledyne Calc./Later, 17322-M-640-1 N-g ! L', I' M UC 571-28-17322 and 571-29-17322 M'r- CONSTRUCTION l 10394-115-C3 17322-640-C120.0 17322-630-C200.0 17322-640-C100.3 4 : - 17322-640 C110.0 17322-640-C100.5 4

Safety Evaluation No. 214 W Rev. No. O Sheet ll of II PILGRIM STATION l FSAR REVIEW SHEET

References:

PDC 86-51 Support a change to provide a Direct Torus Vent Line. List FSAR test, diagrams, and indices affected by this change and corresponding FSAR revision. Affected FSAR Revision to affected FSAR Section is shown on: Section Preliminary f_igal Section 5.3.3 Section 5.3.4 i T- ~ Section 5.4.1 j iJ;b.bt~~i r Section 5.4.7 g.W ,1 m. Section 5.4.8 i STRUCTloINu Section 7.3.4 Attachment I L_ Table 5.2 4 Table 5.2-5 4 Table 7.3-1 Figure 5.2-16, 5.4-1 M 227, Oht.1 Figure 10.11-1 M 220, y,t.1 In addition, the PHPS Technical Specification. Table 3.7.1, Notes for Table 3.7.1, Bases 3.7D/4.7.D. PRELIMINARY FSAR REVISION (To be complet$d at time of Safety Evaluation preparation.) Prepared by: M A /Date: 66; d 2 Reviewed by: X ate: AIf/ /Date:If/87 Approved by: FINAL FSAR REVISION (Prepared following operational turnover of related systems structures of components,for use at PNPS.) (1) Prepared by: /Date: Reviewed by: /Date: (1) Attach completed FSAR Change Request Form (Refer to NOP). Exhibit 3.07-A Rev. 3 (Sheet 2 of 3)

w i Safety Evaluation No. 21 ## Rev. No. O Sheet 1 of M /9 ATTACK 1ENT 1 RECOMMENDED FSAR CHANGES The pages of the following sections, tables, & figures of the FSAR that need to be updattd due to this modification (PDC 86-51) have been marked with suggested updates and included in this attachment for your review. FSAR Sections: 5.2, 5.3, 5.4, 7.3, 10.11 FSAR Tables: 5.2-4, 5.2-5, 7.3-1 'The tallowing drawings will be revised as part of the Plant Design Change package (PDC 86-51) but are not included herein. Dwg. I. D. FSAR' FIGURE TITLE M 227 Sht. 1 10.11-1 P&lD Containment Atmospheric Control System M 220, Sht. 1 5.2-16, 5.4-1 P&ID Compressed Air System M 294 5.2-17, 7.18-2 Heating Ventilation and Air-Conditioning Standby Gas Treatment System Control Diagram ISSUEO eUn CONSTilUCTION N j

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a e c 5 1 n s o f f f f f f a ( r 5 I i o e o o o o o no l n t n n n r n r n p t r a e u e e e e e e e S 2 M w 5 y o o a o o o u o u o u e t t e l s r e a I y e y y y a y a y d l I n p n n n r n r n s a sq a a a e a e a e p p s o t n n n m n m n e o l t b e a D u n e t o e o o o e o e o r T C o n it hr p p p t p t p u l) e L G p l u u u u t c n ve wh wh a o er R u ea gu ro M d ed ohsl d d d og d oo d r ei l u g A vi wis I e l al ee e l e l e l i e l t e l ew R s rft rv s e s e s fh s fh s epo rt P o r epe o ve o vee o o o vml ai rsh l l er l err l hae l hae l eef s ee c t gsnw c l u c l uu c ger c ger c lt p ot r ehhn l ait uor s ss i r u iru h u e whhtl e e rs e rss e has e has e rns.o o ap eet w r t r ee r eee r s r s r a weeeea a tr a t rr a eee a eee a tt h rN l onnnnw ap app nnr nnr ah gE l l i t t p p w t. u tLLth u l u r1 u II t II u ae. P oe p l iiit p w p w p t t p e o w g o wl o wo1 o r o r o wel sO l v .i orn.hr r ommmmi r oe r ot e r mmo r mmo r ai. rr g l aaaah g l w g l cw g aat g aat g l ree o od eeee y ay eec eec owu.t f t s rttt t r s rr s rer s tt a s tta s i Sse i erd i sse tnn.in( ch i ed i oSSSSo h t t h t h t h r h r h i caa agf t cnnnnc t ch t chh t II t CC t aiiiia ag agg CCw II u eee ei n eaaaae n ei n eii n PFa n CCo n ell ssRHR SCC i WNt i i SH i RMn i MML en RMMMMR i s s s s s s vo e e e e e e i .l v v v v v v at l l l a a a a a a . vi l l l d v v v v v v . en h ..._h e e e h o e e e h h h h .Tc1 T 1 234 56 T I 2 T 1 23 T 1 23 T 123 T 1 23 1 7. 2 3 4 S 6 p 1 p p p p p p u u u u u u u o o o o o o o r r r r r r r G G G G G G G \\ l

1 Rev. No. O Attachm nt !, Sheet 5 of 19 l I f' scienolds c' ucon loss cf instrument air to the air operators on the { ca cers. The demister is designed to remove entraincd water droplets and mist from the entering air stream. The electric heating coil is designed An to reduce the relative humidity of the air stream to 80 percent. interlock with its associated exhaust fan prevents the heating toll from operating when the f an is shut down. Each HEPA filter is { designed to be capable of removing at least 99.97 percent of the 0.30 micron particles which impinge on the filter. The charcoal l filters are lodide-impregnated activated carbon filters capable of l removing in excess of 99 percent of the lodine in the air stream with 10 percent of the iodine in the. form of methyl iodide (CH 1) under 3 l entering conditions of 80 percent relative humidity. The accident evaluations using the standard NRC approach are l described in Section 14.9. 'In these analyses the SGTS charcoal filter! were credited with removal of 95 percent of the influent lodine. The system will start automatically upon a high radiation signal frem the operation (refueling) floor ventilation exhaust duct monitor, or upon receipt of high drywell pressure or low reactor water level signals. The system can also be manually started from the control room. Upon receipt of any of the initiation signals, both fans start, all SGTS isolation dampers open and each fan draws air from the isolated Reactor Building at a flow rate of approximately 4,000 ft'/ min. After a preset time delay, one fan is stopped. Cross-connections between the filter trains are provided to maintain ,c I eW rflow on the charcoal 1 the required decay heat removal cool ny filters in the inactive treatment trLin. Q tDiyistharge; to the main stack through a 20 in underyotnd rftf. ftie-SGt Vernt\\are powered from the emergency service porGGNSTRt!"* TION distribution system. L._- i Drywell and torus purge exhaust can also be directed to the SGTS for processing before release up the main stack. See Section 5.2. The l High Pressure Coolant Injection System (HPCIS) gland seal steam condenser exhauster discharge is also routed to the SGTS during accident conditions. The Reactor Buildina Neatino and Ventilating _ . System it ffitrutsed in Caetion 10.9'i During a severe accident, the 5 l { torus can be directly vented to the main stack bypassing the SCTS. p 5** Section 3 4 7-5.3.3.5 Main Stack I The location of the main stack is shown on Figure 1.6-1. The top of the stack is at elevation 400 f t msl. The structural design of the stack is discussed in Section 12. 5.3.4. Safety Evaluation The SCS provides the principal mechanisms for the mitigation of the consequences of an accident in the Reactor Building. The primary and secondary containment act together to provide the principal mechanisms for the mitigation of the consequences of an accident in 5.3 4

sev. .w. v Attechment 1. Sheet 6 of 19 l the crywell. If the leakage rate of the building is low, and the leatage air is filtered and discharged to the elevated release peint the main stack) the offsite radiation ecses (utilizing the SGTS and The that result from postulated accidents are reduced significantly. Rea: tor Building is a Class I structure (with the exception of the secondary containment access locks which are Class Il structures) designed in accordance with all acclicable codes. Design of the Reactor Building for a maxirum inleakage rate of 4,000 f t'/ min at subatmospheric pressure cf 0.25 in of water at neutral a building wind conditicns, results in a low exfiltration rate even during high wind conditions. In the event of a pipe break inside the primary containment or a fuel handling accident, Reactor Building isolation will be effected and the SGTS will be initiated. Both SGTS exhaust fans will start. Af ter a preset time delay, one fan is stopped. With the Reartor Building isolated, each fan in the SGTS has the capability to hold the building at a subatmospheric pressure of 0.25 in of water when dr& wing air from the building at a flow rate of 4.000 f t'/ min. Exhaust fan outlet damper controls on each fan are provided to maintain the required flow rate. The RBICS performs the required isolation actions of the SCS following receipt of the appropriate initiation signals. Following -initiation, the Reactor Building ventilation isolation dampers close within 3 sec. The.RBICS also autr;jipily.. trips the Reactor ~ star s-p. The normal L.ng op @QhSGT.S..CrefuehqqQ1oor Building supply and exhaust fans, anc design flow rate in the Reactor Build exhaust duct is 40.000 f t'/ min. During - do hp.1'l e increased to approximately 50.000 f t, a( J% more than 3 sec for fission products 4W4-44m' rettu!ated ce handling accident to travel from. the operating (refueling) floor ventilation exhaust radiation monitors to the isolation dampers.

Thus, no direct release of fission products to the environment (bypassing the SGTS filtration processes, and_ the eleva_ted release is possible.~eicept when direct torus }

goin_tgo_vided_by th_e main stack) e vent path is usef durine a severe accident. r-- ( The SGTS filters exhaust air from the Reactor Building anti discharges the processed. air to the main stack. The system filters particulate m and lodines from the air stream in order to reduce the level of airborne contamination released to the environs via the main stack. J When the system is exhausting from the Reactor Building, the building is held at a minimum subatmospheric pressure of 0.25 in of water. Appendix G identifies. requirements for establishing secondary / containment (Safety Action 27). following an assumed pipe break inside the, primary containment (Event 39), and following an assumed fuel handling accident (Event 40). Secondary containment is ) spent not established following assumed pipe failures which result in the release of steam into the Reactor Building (Event 41). The following piping which is located within the Reactor Building and normally contains hot fluids at reactor pressure was considered: High Pressure Coolant Injection (HPCI) turbine steam supply line; 5.3-5 Revision 6 - July 1986

y ;;S-TSA.; Attochment i Sheet 7 of 19 CCf.iRCL OF CCMBUSTIE;.E CAS Cot;;C; TX10t:5 IN COf.iAIMC.i b 5,4 5.4.1 Introduction This A system for control is provided as reguared by 20CTR$0.44(g). contr l i system is provided for (LOCA) combined with following a postulated loss of coolant accider.:of Core Standby Cooling Systems l degradat2on, but not total failure, (CSCS). Degradation, but not total failure of the core standby cooling function means that the pe rf ormance of the CSCS is postulated, for the purpose of design of the Combustible Gas Co localized clad melting and metal-water reaction 'S System (CGCS), not to the extent postulated in 10CTR50.44(d)(1). The degree of!$ that there could be performance degradation of the CSCS is not postulated to be i, & jey sufficient to cause core meltdown. fo E The Containment Atmospheric Control System (CACS) is provided to, W,, I obviate the possibility of an energy release within the Primary,j, Containment form a Hydrogen-Oxygen reaction following a postulated

• 3 j

-l LOCA combined with degraded CSCS functioning.. This is to be ,, g j l than 41; *4, m, l 3 atmosphere containing less by maintaining an accomplished The> the Drywell and Pressure Suppression Chamber (Torus). ,eh oxygen in M;i i system willt It Perform initial purging of the Primary Containment \\ a 1. nitrogenmakeupgasduringnormal.E{,E 2. Provide for a supply of >,s operation or emergency )eoe hMnes tg. the Standby EeI D6dng,Npglgions ' S3# 3. Provide for nortr.a1 and p. rge 1i Gas Treatment System (SGTS. ! for S hf 6 I Provide for emergency exh4u,s n release of contaminated DryweAl. J ~r- -pe==*a t 1e vT UET 4. '"Ee I &. Provide pneumatic supply to instruments inside the drywell " e, 8 5. O$j Source of Hydgrogen Accumulation in Containment mI* i 5.4.2 the!yES Following the postulated design basis LOCA combined with degradedS CSCS functioning, hydrogen and oxygen may be evolved within 3 reactions and from {f g O r from postulated metal water for post ! *jg primary containmentIn the Pilgrim Nuclear Power Station design, 0$$ l radiolysis. gas control, the oxygen concentration is chosen ,g5 accident combustible as the parameter to limit. E*O! ggg 5.4.3 System Description "E $ 3 ,eg reguires a method for control of hydrogen gas that may 4** 10CTR$0.44 (a) be generated in a BW primary containment following a poetulated LOCA by metal-water reaction of fuel cladding and coolant, radiolytic and metallic corrosion. 10CER$0.44 (b) decomposition of coolant, requires a system to measure primary containment hydrogen 5.4 *- Revision 5 - July 1985 ee e

I Saf ety b a' uation No. I Mq Rev. Nc.C PNFS-TSAR At t a c hment - 1 s Sheet 8 ef 19 The valves in redundant paths are powered from independent Class IE g distribution systems each of which is powered from en emeraency y diesel generator after a loss of_offsite power ffhe control switches l for redundant valves are located in separate Class IE control panels in the main control room. Conduit and permanently installed equipment required for purging and repressurization functions are g I located in se_isdeally designed,,mjssile protected buildings, except l gM$e",_fil.1.c onn,e c tions which,,,are,locat,ed outside of, secondary

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_co_n_t_a inme nt but separa,ted._, Redundant conduit systems are separated gg commensurate with identified hazards. All conduit and permanently ie g l installed equipment required for purging and repressurization uN l functions are supported to meet seismic Category I requirements o except for Na supply equipment described previously. The solenoid valves are ASME III class 2 and are qualified environmentally and seismically to the requirements of IEEE 323-1974 IEEE 382-1973. and IEEE 344-1975 for the expected conditions. The valves are rated at 120V ac and are designed to operate between 80 l and 110 percent of rated voltage. This range is compatible with expected bus voltages at Pilgrim Nuclear Power Station.= i e The control switches have been qualified to the requirements of g; IEEE 323-1974 for operation in a control room environment. The g; Class IE panels (see Table 7.8-3) and thel g switches are mounted on y combination has been qualified to IEEE 344-1975 for the Operating gg Basis Earthquake. The switch's electrical ratings exceed loading 3o Ae requirements. lm I The cable and wire used for this modification have been qualified to IEEE 383-1974 for fire and ambient conditions exceeding those ee required for this installation. The 600 V No.12 AWG control cable $( 1 o, { has voltage and current capabilities well above that required. f o i ( I a Osi. ther'e Asio IU control of the solenoid valves io automatic isolation capability. Iso: g Mv('gk (been EE i i .c vggtS*T[tt)CTION n. provided because: >,g 1. The valves are always kt e operation ee, >eu 2. The valves are required to be operated during a high drywell tao pressure condition and must be available independent of u" reactor water level. High drywell pressure and low-low [ *E N ~ reactor water level are the normal containment isolation / signals 4 l N, makeup and ventilation valves are also provided for use under nonaceident conditions. These will automatically close gom receipt of an accident signal. However, these valves may be used after an j are available and a l accident provided the required power supplies low-low water level signal is not present. Refer to Section 5.2.3.5 l and Tables 5.2-4 and 7.3-1. i S.4-3 Revision 2 - July 1983 I

l Safety Evaluation No. giaq Rev. No.D { Attachm2nt I f FNPS-FSAR Shaet 9 of 19 ,s 5.4.5 Combustible Gas Monitoring The exising Containment Combustible Gas Honitoring System (CCGMS) censists of two redundant, remotely operable, seismically qualified { hydrogen analyzers. The hydrogen analyzers can continuously monitor main j Crywell hydrogen concentration and have a remote readout in the control room. ] 5.4.6 Radiological Consequences of Containment Venting An evaluation of offsite doses which would be incurred as a result of containment venting to limit containment pressure has been performed in a manner consistent with Regulatory Guides 1.3,1.7, and 1.45.. results of this analysis indicate that the doses to receptors at The the LPZ would be well within the' limits of 10CFR100. This analysis assumed that venting at the rate of 50 standard ft / min through the 3 SCTS would be initiated at 80 hr after the reactor was made ical and venting would_ continue for 30 days. 7 ,J,aghaftwQages) 5.4 y,. 8. 4 ) References 1. GE Letter No. SSX:79-64. 2. July 13, 1979 Letter, W. J. Heal (GE) to S. A. Giusti (Bechtel). 3. BLE-459 dated September 25, 1975. Supplement No.1 to Dresden Station Special Report No. 39 and QAD 4. Cities Special Report No.14. la,.S U ~ F v... ~K e.; L. CONSTRUCTION J O 5.4-5

Safety Evaluation No. LI44 Rev. 0 1 Sheet 10 of 19 S.4.7 Direct Torus Vent Line 5.4.7.1 Introduction The consequences of several accident scenarios are more severe than the accidents previously considered herein. The primary containment pressure during these accidents is estimated to exceed its design capacity. Thus, the primary containment fails, releasing reactor fission products to the secondary The direct torus vent containment and potentially to the environment as well. line (DTYL) provides an emergency primary containment vent path to prevent, or ma essure within t e at least slow down, the buildup of potentially 'EMN $N"Y b _W M# 5.4.7.2

System Description

M. The DTYL is an 8" carbon steel pipeline connecting the 20" torus main exhaust line to the underground 20" sain stack exhaust line. The 8" DTYL starts at a new branch between the existing 8" containment isolation valves in the 8" section of the 20" torus main exhaust line. The D1YL terminates in the 20" main stack exhaust line, several feet downstream of the SGTS outlet valves. The line includes an 8" air-operated, normally-closed butterfly valve which Both serves as the outboard containment isolation valve for the DTYL. electrical power and' valve operator active gas (air or nitrogen) supply are taken from " essential" or reliable sources, or are backed-up to ensur_elhet___, the system is available during a station blaAmi-e tMt-et-Mtr%ent71n s i !SSUED FOR o av'"*- ith'Vinter WAdde'ndiW5e'dtfo'n h The DTYL meets ASME B&PV Code (1980 Edition !!!, Subsection NC for Nuclear Class 2 requirements up te andrinc10dirig tht. L isolation valve. The new piping downstream of the1sointibh WTiis meets ANSI 831.1 (1977 Edition through Winter 1979 Addenda) requirements. During normal or general transient conditions, the DTYL outboard isolation In response to a severe accident, plant management valve would remain closed. could direct the control room operators to esploy the DTYL to relieveIn this case, the operat excessive pressure within the containment. follow a written procedure to perform the following basic actions: Close, or confirm closed, the outboard isolation valve for the torus o main exhaust line Close, or e nfirm closed, the SGTS outlet valves to prevent the high containment pressures from back-pressurizing the SGTS filters o Open the two DTyL, isolation valves o Optimally, turn off the SGTS which likely came on automatically in o response to a high drywell pressure signal

baIEty tvaivanon n6.! i i g Rev.-3 Attach,9ent 1 'i Sheet 11 of 19 5.4.7.3 Radiological ~ Consequences of DTVL Use The exhaust gases released by the DTVL during a severe accident would have initially been " washed" by the, suppression pool water which would reduce the These exhaust gases are vented to the highest vent particulate released. point (main. stack), avoiding the ground level release of radioactive material in case.of containment failure due to over-pressurization. 4 i m. 'l [ C. ~C. 3 J IJ i'.). l s.3 DS" n. .A

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s. ~ .,>.;m-~,,s . nl ,.) l'.j fi ft, .:ii.* - - ---.':== :.:.-. _... :. i f 4 1

P.ev. No. D 'o' pgps.rsAR .t' r Sheet 12 of 19 e Traversing 2ncore probe i RHR reactor shutdown cooling supply RHR reactor head spray Reactor water sample lines Reactor water cleanup o g. a so Drywell purge inlet and makeup gas *, ** jif eje Drywell main exhaust. 4E ) suppression chamber exhaust valve bypass *, ** Ta E f M *; Suppression chamber purge inlet and makeup gas *, ** cE j

• e suppression chamber main exhaust gs I

I-Drywell exhaust valvis:Uypsiss*,----- g-l- VVI'h)?ry6Y;1,,1J 'a - h}' }J 8 RHR-LPCI supply p~* t ? ;'~ "~ c i \\ * +- RHR to Radweste ( 7., j,? E,.o 8 3 y* e Containment atmosphere sampling lines containment makeup and ventilation valves are also

• g; provided for use following an accident condition.

g%vi These are remote manual operated. Refer to ,E$' g~*, Section 5.4.3. % $ I. ' { o The reactor water low level isolation signal can be by

> b q passed. These valves may be opened anytime provided

,y y%i j the low-low water level signal is not present. j

• R and lower of the reactor vessel low water level i *E g,, I 1

The second isolation settings was selected low enough to allow the,"ot*," from the reactor for a predetermined time,i,E removal of heat following the scram, and high enough to complete isolation. g in time for the operation of CSCS in the event of a large ,5,,,y g barrier. This second 2 H

• break in the nuclear system process low water level setting is low enough that partial losses of '

) feedwater supply would not unnecessarily initiate full g l / ssolation of the reactor, thereby disrupting normal shutdown - Isolation of the following -. / procedures. or recovery init.ated when the reactor vessel water level d pipelines is falls into this second setting. I All P.,ur main steam lines 1 HPCI, RCIC, and main steam line drains ~ J 7.3-22 Revision 2 - July 1983 l (

p .,o. s v ...m PhT5i-FS AR At{$c ent 1 Sheet 13 of 19 L^_ included here to make the listing of isolation functions I-compiete. ) ) 6. Primary Containment (dryvell) High Pressure High pressure in ti.e drywell could indicate a breach of the nuclear' system process barrier inside the.drywell. The automatic closure of. various Class 5 valves prevents the j l release of significant amounts of radioactive material.from J l the primary containment. Upon detection of a high drywell j l pressure, the following pipelines are isolated, see Table j l-7.3-1, signal F. ] { Traversing incore probe RHRS shutdown cooling supply RHR$ reactor head spray Reactor water sample lines Drywell equipment drain sump discharge Drywell floor drain sump scharge Traveling incore probe tubes Drywell purge inlet and makeu gas *, % d { jt F0 ~7' }, q; i,. 4 -s. {,,.-,....,.,., Drywell main exhaust i; suppression chamber exh'aust v'aTve bypas"s,7*~~~~ ~ ^ ~ ~~ T Suppression chamber purge inlet and makeup gas *, ** I gp.p_ression chamber ma_in exhaust r recttorusven't***J I F Dryw' ell' exhaud~ valve bypass *, ** RHR to Radweste s containment atmosphere sampling lines The primary containment high pressure isolation setting 4s l I selected to be as lov as possible without inducing spurious isolation trips. See Table 7.3-1, Signal F. Containment makeup and ventilation valves are also ' ) provided for' use following an accident condition. ] These are reacte manual operated. Refer to Section I 5.4.3. i l \\ ~ l 7.3-15 Revision 2 - July 1983 l

Rev. ho.D PNPS-FSAR Attachment'l Sheet 14 of 19 ' 'a The reactor water lov level isolation signal can be by-l passed. These valves may be opened anytime provide d 8 the low-low water level signal as not present. i 7. RCIC System Equipment Space High Temperature a High ternpe rature in the vicinity of the RCIC System equipment could indicate a break in the RCIC steam line. The automatic closure of certain Class A valves prevents the excessive loss of reactor coolant and the release of significant amounts of radicective material from the nuclear system process barrier. Whern high temperature occurs near the RCIC System equipr.ent, the RCIC turbine steam line is isolated. The high temperature isolation setting is selected far enough above anticipated normal RCIC system a i operational levels to avoid spurious operation but low I enough to provide timely detection of an RCIC turbine steam line break. See Table 7.3-1. Signal K. 8. RCIC Turbine High steam Flow RCIC turbine high steam flow could indicate a break in the RCIC turbine steam line. The automatic closure of certain 'g Direct torus vent valves are provided for use followiThe primary c 'C an accident condition. high pressure isolation signal can be bypassed. These are remote manual operated valves. - - _ - - =. =. - - f } ; -{I Q =---f CONST!S.!CTiON j 2=..~.=:; - 4 t j l I i , ~., j O 'I l 7.3-15a Revision 2 - July 1983 i 0 f* /

key, ho, v / ~~ 34':" <[i 'PHFS-TSAR Sheet 15 cf 19 .s ,1' The.legac arrangement) used. for this function,.shown on Tagure 7.3-7.. 1s ': an exception to the. usual s logic .[ requireraent, because high steam flow is the s'econd method of'(' g detecting an HFCI turbine stee.m.line break. , g.( 3 - - 3 j 12.'HPCITurbineSteamLine}ovPrepriure s 3 + 3 'HPCI turbine steam line low pressure. f5 used to .Q, e . automatically close the two isolation valves in the HPCI . g~ O l turbine steam line, so that steam and radioactive gases will not escape frop.the HPCI turbine sheft : seals into the ~ ~ Reactor Building af ter steam pressure has decreased to such 1 a low value that the turbine cannot be operated. -The -isolation c setpoint is chosen at a pessure below that where the HPCI turbine can operate efficiently. See Table 7.3.1,

• 1 Signal L.

Reactor Water Cleavaup Ept.ei 3 pac'e,High Testperature 13. High temperature in the vicinity # of the reactoryoter cleanup (RWCU) equipment and piping could indicate ia. ' break-in a RWCU.11M. Th+ automatic closure of certain Class & j-val,ves prevents the ticensive losh*of 'L reaccer coolant?amd ( 'J thO release of significant amounts of radioactive material k1'from t*4e nuclear system process barrier. When <jhigh ( f L. temperature. occurs near the RWCU equipment, th'e RWCU 16ystes - t,t 'Is isolated. The high temperature isolatied ' setting is selected far enough above anticipated? 'nerphl' system ._ i om-itoistio@3H= Tov - i .! operational levels to avoid s 'e: tion gof g $ipe>Dreak',(sel h enough to provide timely 6 y c l.J t/ W b * ' ' \\ Tgble7.3-1,signalJ. a e,3n c'rba !!*"{ { N 5 i React $r' Water Cleanup System Hid MoWJ ik....-{h, y b,. ] s 14. 3 , m RWCU high flow could indicate a break in a RWCU li'se, The automatic closure of certain Class R valves pr' events the excessive loss _ of reactor coolant, and. the release of significant amounts of radioactive materials' from the nuclear system drocess barrier. Upon detection of RWCU high flow, the RWCU line is isolated. The high flew trip setting was selected high enough to avoid spurious isolation, yet 0 (" lov enough to provide timely detection of line break. see {j Table 7.3-1, Signal J. y 3 s, w

15. High Reactor Vessel tressure j ;u J

t High reactor vests.1 piessure is used'to automatically close 4% 'the two isoletica Oves in the RHR pmps' shutdown 1 cooling dh suction piping z.o that the RHk low p:4sture piping wilt not be threatened by, swprpressurizatson. Tne isolation setpoint 4, chosen at a pressure below wnerd thn RHR piping could be isoverpressurized. See Table 7.3-1, fignal U. f [.t a 4 - g j! ggf mes %eto EmC4*.M s .N. See Insert C on page 16,,/ j 7 ",,,,3-17 o 7 Q ;. c P y e 4 1 i }' } f a--

Safety Evaluation do. 21 4 Rev. 0 I Sheet 16' Of 19 esd7 O As N2 Radiation in Reactor Building Refueling Floor Vent Ex t, Duct k High radia in refue' ling floor vent exhaust duct uld indicate a ,p '[- gross release o ssion products from the fuel igh radiation in-refueling floor exh duct initiates isol on of the followirl pipe s lines. (See Table 7.3 ignal V.) Suppression chamber main e st o o Direct torus vent i 'The high radiation setting is selected enough above background rad on levels to avoid spurious iso on, yet low enough f ( to prompt 1 ect a gross release of fission products m the fuel, mseu c 4 iSSUilD 95 W Ir g .. s p, g,7. > 3 a m g 3..,,s..;e g ..L. .. v c n. g, I Suppression Pool High Radiation ~ ~ = = * ~ ~ ~ ' ~ K High radiation in torus could indicate a gross release of fission products from the fuel. H1 h radiation in torus initiates isolation of the direct torus vent pipe ine to prevent release of significant l amounts of radioactive materials. The high radiation trip setting is selected high enough above background radiation levels to avoid I spurious isolation, yet low enough to promptly detect a gross release of fission products from the fue, to the main stack, within the I I r allowable limit. See Table 7.3-1. Signal Z. i L ) i l

PNTS TSAR {) Sheet 17 of 19 (E[

13. 'Hagh-ter;erature.in the spaces cccupsed by the RHRS

~ (shutdown cooling).and piping outsade the pramary > ;y E conta ireent is sensed by temperature switches that activate-c "o L - alarms only. Andscatang possible pipe breaks. I [ U '6t A typical arrangement is shown on ' Figure 7.3-8. Autor:.at ic

s. -

5N isolation on hagh temperature is not required since the C' A o en i reactor vessel low water level isolation function as adequate in preventing the release of sign 2ficant amounts of .h {3 5 1 I radsoa:tive material in the event that either of these two oMU systems suffers a breach. "$ $ 5 h *

14. High temperature in the vicinity of the' ItWCU system is Egg 5 sensed bY four sets of two binetallic temperature switcher.

A set of two temperature switches is installed in each of e $$,L 3 u M.* the four areas to be monitored: each set is a one out of two trip system and capable of initiating isolation. E kj '=', ,hph$

15. High flow in the Reactor

• dater Cleanup Syster supply line is sensed by two differential pressure switches which monitor t]* g $

c: E the pressure difference across an elbow installed in the ac w E o-Reactor Mater Cleanup System supply lina. The arrangement of the differential pressure switches is similst to that shown on figure 7.3-12. .The. tripping of either switch ,g Jnitiates isolation of the RWCU system. f i Channel a$d logic relays are high reliability relays equal to type [ HTA relays made by the General Electric Company. The relays are. ( selected so that the continuous load will not ex:eed 50 percent of i the continuous duty rating. I ~ F gd J": p Nq 3 CI 8' \\ 7.3.4.8.1 High Temperature Sensors independen:e.. Th] Q CT'D $ i'/"T[r*j.11J/i'st'ahee'- f e 'T i \\ The

location, spatial EE*'

tripping of the high temperature sens'o' rs in-'EheW2N"ife#ainlinei~HPfi" j e ~

• L i

turbane steamline and RCIC turbine steamline are detailed in this l section. Q ~f i .. w S C, lt Table 7.3-3 lists the areas outside the primary containment where e main steam. HPCI, and RCIC steam lines are routed. This table also .o } to E lists the leak detection sensors, summarises the physical separation of sensors, and specifies the set points at which asolation of the I II

• respecting steam line would be initiated.

M*' c,g f Potential leak sourcer and rates which would initsatt isolation are E I i Ooe as follows: f MainSteamTunnel %1E q,g This area contains feeduater,

cleanup, and usin steam piping.

Isolation of the main stearr lines will be initiated at ventilation I I' o E exhaust temperatures from the main steam tunnel of 160*T to 170'T. j which would result from steam leaks equivalent to 10 gal / min and / )$dh, ( o g g. greater. The feedwater and cleanup systems normally operate at / l 7.3-21 .S 1 i l

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m._.--- 3e zm ._ { G e f.O o Vl t; g & c. T s 't O G s h E l O' 411 A( t4 46 *J T r f l FWPS.FSAR 1hbis 7.)=1 It0 Lair 10e S!taAL 00085 Pos taatz 7 3.a eneeristies g Beessar vessel law water tent. seres and siese taalstsam J A* vnavne easeys sata etens M ees. asseter veseal asw law unter level. Laitiate BCIC SPCs and .F elane man stens une toelatten mises. SLp meistias. mio stema itse (ales ensseo seses). . C* I une trunk. emia egens uns (etens line hip apnee sagere. ey ture er hi p stans fism). l anneter las law level er high dryeell pressam. eelmet UC2 8 ace elase etter laep alves. Bie aryeell preseare. elane num/shuteses esmLing and tend F* sprer pine the R5 te steamste staves. &.y toestar sneeel lar law inter level and law preseems er hip y O arymu pee m. satssate em sprw ama no erstems. i il,me b,reak is elaammy erstes e bid opnes tasperature, er J' 1. u se,r . et et u .,1 (.. m-t. - e se t e t.re er..t . ~ et J.t ISSUED FOt '~~~ ,r .a et.a. mas. S.,,- (, 1 lies opmee tegentare er him etaan flaw) er law staan man - :. ; 3...,,,J,,y, *f"'yI g g j 1 t .pagt e ~ -~ a = em Ie.. y,* preneum. l use treak la age shutesen and need ensues (hip eynes me saw mten; alare emir 6 se ante slasen). - l las akta steam une presseev 64 least to amaa turttw GW j 4

• Pe amas amar).

/ \\ las errumu pensum. saaee eestalammet spyw valies. j s las remeter pmaann peresselse to spee een opew ese M T unlese. 35$. reestar vessel pressure.. glane RS stadeven _eemuas - ^7 4= y U . a we eme n n, = 1. a. 8 "Q "w ~ q# Ui M PIM L severesum et auslet er caensup erstem nearepaarstTaXshn 'j l ~7Il A -.,, m.m e-m e,. ,n eneast, lagde eMrol ersten essented. f -@r amasse enmani e6tet free esotest rece. sees ammeter tse enter level - isolate asia stens Mae (earegs

• c se tus m en).

3C1C or RFC1 stone supply valve (as appaleable) met fin 1% I g.clanee.- e.,ee,,,,re., sue tie,e av mt.,e. ei.. ee .,,en.e. o.e4 ~ .,,eee.ro to,e.m, - ties..,see,,,.r,e m n j veneet teslattaa samtrol erstens other twactions are given for tarecian. y.b stan emir. g s r: 9 or u f

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