ML18116A307

Forwards Final Design Basis for Mod to Auxiliary Bldg Ventilation Sys & Justification for Deviations from Reg Guide 1.52,Revision 2.Const Should Be Completed During Unit 1 Repair Outage

ML18116A307
Person / Time
Site:	Surry
Issue date:	08/09/1979
From:	Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Harold Denton Office of Nuclear Reactor Regulation
References
045B-020177, 45B-20177, NUDOCS 7908130452
Download: ML18116A307 (52)

Text

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..,f VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGIN IA 23261 August 9, 1979 Mr. Harold R. Denton Serial No. 045B/020177 Office of Nuclear Reactor Regulation U.S. *Nuclear Regulatory Commission Washington, D. C.

20555 PO/RWC:svm Docket Nos.:

License Nos. :

50-280 50-281

. DPR-32 DPR-37 Attn:

Mr. Albert Schwencer Operating Reactors Branch

Dear Mr. Denton:

This letter provides the final design basis for the modification of the auxi-liary building ventilation system at Surry Power Station.

Our letter dated July 28, 1978 presented the conceptual design and promised additional informa-tion as it became available.

The auxiliary building ventilation system is to be upgraded according to the eight items presented in Attachment I.

The detailed operation of the modified system is presented in the System Description and flow diagram (Attachment III).

The deviations of the modified safety-related filtration system from the positions of Regulatory Guide 1.52, Rev. 2. and the justification for these deviations are provided in Attachment II.

The final design is nearly complete.

Construction has begun and is scheduled to be completed during the Unit No *. 1 Steam Generator Repair Outage.

This letter meets our commitment to provide additional information.

We would be glad to answer any questions or provide further information as requested.

RWC/svm.:1I2 cc:

Mr. J. P. O'Reilly, Director Very truly yours,

~. )!JQ. --,diaet"~.

C. M. Stallings Vice President - Power Supply And Production Operations Office of Inspection and Enforcement-:Region II

. d,.* 79.08130~,~*-.

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-"1~08i3Ctf52.Attachment I Page l of 6 MODIFICATIONS TO AUXILIARY BUILDING VENTILATION SYSTEM nETU to REACTOR nu~KET Filtering ECCS Leakage Following a LOCA Withof!.l~eeding Filter Gapaci:tf':*,.,.,~:*.L Filtration of ECCS equipment area exhaust air following a LOCA without exceeding the filter design capacity is required to limit control room doses resulting from ECCS leakage (postulated in Reference 2) within the guidelines of CDC-19.

The existing auxiliary building central area exhaust system draws air from all six charging pump cubicles, regardless of the operating status of the pumps.

The design flow rate of this stream alone exceeds the existing filter capacity.

Furthermore, the air distribution across the faces of the filters and the absorbers was not designed to be uniform.

Nonuniform air velocities can decrease the residence time and prevent assurance of satisfactory removal of particulate and gaseous iodines.

The following four modifications are to be made to the system to ensure proper filtration of exhaust air from ECCS leakage following a LOCA.

The first two changes will reduce the flow rate of the charging pump exhaust system to 22,000 cfm following a LOCA.

The total ECCS equipment area exhaust flow rate becomes 36,000 cfm, which is the capacity of one filter train.

There is 12,000 cfm from either Unit 1 or Unit 2 safeguards exhaust system and 2,000 cfm allowance for damper leakages.

1.

Installation of a two-position damper in the exhaust duct of each charging pump cubicle to open and exhaust air when the pump operates and close when the pump stops.

2.

Disconnection of the exhaust d~cts of nonsafety-related equipment cubicles from the charging pump exhaust system and connection to the auxiliary building general area exhaust system.

3.

Installation of a perforated plate air distribution and straight-ening subplenum in the inlet and outlet plenums of the two safety-related filter housings to provide uniform airflow through the filter elements.

4.

Seismically supporting the charging pump exhaust ducts to qualify the entire ECCS leakage collection and filtration system as a safety-grade system.

B.

Maintaining Thermal Ambient of ECCS Equipment Areas Following a LOCA Limiting the design temperatures of ECCS equipment areas to the original design temperatures simultaneously with filtration of exhaust air is a safety requirement following a LOCA.

The ECCS equipment areas are ventilated and cooled by three separate exhaust systems designed to limit area temperatures to a maximum of 120°F.

The exhaust fans are presently sized to draw design flow rates when the exhaust systems are aligned to bypass the filters.

When th~se exhaust systems are diverted through the filters, the additional resistance of the filters reduces the fJow rates oft£~~if1[fbfli~nrf1hnlffrl[(ncreases temperatures above 120 F.

n JUW\\~1 fi.tf\\~luit IJ.U~I\\

Attachment I

Page 2 of 6 To limit the temperature following a LOCA to 120°F with airflow from ECCS equipment areas diverted through the filters requires the installation of two safety-related, high head fans, (l-VS-F-58 A & B) sized to draw 36,000 cfm each.

C.

Periodic Verification of Filter Performance Monitoring the performance and availability of safety-related filters is required by references 2 and 3 in the form of a new technical specification.

The existing technical specification (Section 4.12) requires laboratory analysis of charcoal absorbent once every 12 months.

In the present de-sign, charcoal samples are withdrawn from a charcoal tray, new charcoal inserted, and the tray reinstalled.

Implementation of the new technical specifications would require charcoal sampling and analysis after every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of filter operation and in-place halogen leakage testing of the absorbent bank after each complete, or partial, replacement of charcoal trays.

To permit periodic laboratory analysis of charcoal absorbent, without a monthly halogen test of the absorbent bank or breaking their gasket seals, requires the installation of 18 charcoal canisters in parallel with the main absorber trays for the two safety-related filter trains.

The cani-sters will be filled with the same absorbent as the main absorber trays and will be removable from the outlet plenum.

D.

Relocation of Filtered ECCS Leakage Release Point Relocation of the release point of the filtered ECCS leakage is required to limit control room doses resulting from changes in site meterology (imposed by reference l) within the guidelines of CDC-19.

The existing release point of the ventilation exhaust air is on top of the service building.

A new stack will be installed on the roof of the personnel hatch of Unit No.

2 containment and the discharges of all exhaust fans will be diverted from the old stack to the new stack.

The sampling point of the continous radi'ation monitor will be relocated to the new stack.

E.

Redundancy of Safety-Related Components Redundancy of safety-related components is required by reference 2.when the auxiliary building ventilation system is aligned to cool and filter ECCS equipment area exhaust air following a LOCA.

l.

Redundancy of safety-related filtration capacity - The 36,000 cfm capacity of each filter train equals the maximum design exhaust flow rate from the ECCS equipment areas (discussed in Item A).

2.

Redundancy of the high head fans to draw design flow rates through the filters -

The capacity of each high-head fan is 100 percent capacity (disccused in Item B).

3.

Redundancy of dampers to ensure diversion of ECCS equipment area exhaust air through the safety-related filters -

This requires

Attachment I

Page 3 of 6 the installation of parallel dampers for each of the safegu~rds and charging pump exhaust systems to provide redundant flow paths to the tilter following a LOCA and the installation of dampers in series in the other exhaust systems to provide redundant closure following a LOCA.

4.

Redundancy of safety-related controls and power supplies - These changes will be made as required.

F.

Upgrade Purge Exhaust Duct and Safety Classification To limit off site doses within 10CFRlOO guidelines requires upgrading the containment purge portion of the auxiliary building ventilation system to mitigate the consequences of a refueling accident inside the containment, as postulated in reference 4.

Th~~ _e-qtire _ exlJ.~u_s~ ventilation syst~m required to filter the purge air following a refueling accide-nt h"as a""safety" gracfe" cfas-siffratfot1~-- e"xcept the purge exhaust duct between the containment isolation valves and the safety-related filter trains.

This duct is not seismically supported.

To permit filtration of purge air following a refueling accident, simul-taneously with a design basis earthquake, requires the seismic support of the Unit No. 1 and 2 purge exhaust ducts between the containment purge exhaust isolation valves and the safety-related filters.

An alternative method for handling the consequences of a refueling acci-dent would have been containment isolation.

This approach would have required:

1.

Upgrading the radiation monitors and the purge air exhaust dis-tribution ductwork inside the containment to a safety-grade classification.

2.

Changing the power supply of the containment isolation valves from nornial to emergency.

3.

Periodically testing the closure time of the valves.

This approach was discussed with your staff at various times and our decision not to pursue this approach was presented in our letter, Serial No. 059/012478 dated March 7, 1978.

G.

Filtering Frequently Contaminated Exhaust Air The technical specifications of references 2 and 3 impose surveillance testing requirements based on total hours of safety-related filter opera-tion.

Minimizing filtration of contaminated exhaust systems through the safety-related filters will therefore reduce the frequency of testing and the possible outage of the filters for maintenance.

Frequent contamination of some exhaust systems (auxiliary building general area and purge) and unreliable diversion dampers on all exhaust systems has necessitated, as a temporary operational measure, diversion of all ex-haust system~ through the existing filters, regardless of need.

To mini-I J

Attachment I

Page 4 of 6 mize the use of the safety-related filters during normal station operation requires:

1.

A new nonsafety-related filter to treat the auxiliary building general area exhaust air system, which is in continuous opera-tion.

2.

Replacement of all defective diversion dampers with heavy-duty dampers having specified and tested leakage characteristics to permit the alignment of noncontaminated exhaust systems around the filters.

3.

Containment purge air may continue to be filtered through the safety-related filters.

The duration of station operation in the shutdown purge mode would not significantly affect filter avail-ability.

H.

Restoring Original Design Airflow Rates for Auxiliary Building and Purge Exhaust Systems Restoration of the original cooling design conditions in the auxiliary building and the purge exhaust rate of the containment simultaneously with filtration of contaminated exhaust air is a nonsafety requirement which facilitates station operations and availability.

The existing exhaust fans, serving the containment purge and auxiliary building general area, are sized to draw design flow rates when the exhaust air is aligned to bypass the existing filters.

When these exhaust systems are diverted through the filters, the additional resistance of the filters reduces the flow rates of the systems which, in turn, increases auxiliary building cubicle temperatures and the duration of containment purging.

The changes to the system operation are accomplished by the following modifications:

1.

Installation of a nonsafety-related high-head fan, (2-VS-F-59),

sized to draw the design flow rate of the auxiliary building general area exhaust system through the nonsafety-related filter.

2.

Installation of automatic capacity control for fans l-VS-F59 A &

B to draw any of the other exhaust systems, including the purge, through the safety-related filters, each at its respective design flow rate.

3.

All existing fans will be used only to draw the exhaust systems when bypassing the filters.

Removal of the purge exhaust fans (1-VS-F-SA and B) since purge air is rarely released without filtration.

SAFETY IMPLICATIONS During Normal Operation, the modified ventilation system maintains design flow rates, which, in turn, limit the temperature in the ventilated areas to design conditions whether the exhaust streams are routed through or around the filters.

Attachment I

Page 5 of 6 In the LOCA mode, the system maintains design flow rates of the charging pump cubicles and safeguards building streams through the safety-related filters.

This ensures adequate cooling for all ECCS pump motors and adequate filtering of potential ECCS leakage into the exhaust air.

Upgrading the containment purge portion of the auxiliary building ventilation system improves the safety performance in the event of a fuel handling acci-dent in the containment.

The system will perform its safety function, assum-ing the worst single failure, without taking credit for the proper operation of any nonsafety systems.

During Refueling, the modified ventilation system will still have to be manu-ally aligned as in the existing design.

However, the isolation trips dampers at the safety-related filter inlet header would be manually deenergized from the control room to prevent a spurious signal from changing isolation damper alignment.

A refueling accident in the fuel building or the containment would not require a change in system alignment.

A LOCA in the operating unit during a refueling operation in the shutdown unit would require closure of the con-tainment and fuel building-exhaust dampers and permit filtration of the safe-guards and charging pump cubicle exhaust air.

This would be accomplished by manually reenergizing and closing the isolation trip dampers from the control room.

In the modified ventilation system, the two safety-related filtered exhaust fans are powered from the Unit 1 and Unit 2 orange buses.

Provis ions have also been made to supply electric power to the fans from the purple emergency buses of either unit.

This prevents a force shutdown of both units in the event of an extended outage of an orange diesel generator of either unit

• The Categroy II filter bank is p*rovided with automatic fire detection and manually initiated fire suppression (water).

This is consistant with the fire protection requirements for the Category I filter banks (T.S. 3.21, 4.18) but the fire protection for the Category II filter will not be subject to the re-quirements of the technical specifications.

r--

REFERENCES Attachment I

Page 6 of 6

1.

The NRC's request for additional information, dated July 9. 1976.

2.

The NRC's request for additional information, dated February 1, 1977.

3.

The model technical December 23,

1974, specification, and referenced enclosed in the NRC letter, dated in question no.

14 of Reference 2.

4.

The NRC's request for additional infonnation, dated May 20, 1977.

REGULATORY GUIDE ITEM.

1. 52 POSITION C.2.a 2

C.2.a 3

C.2.a 4

C.2.b Attachment II Page l of 4 AUXILIARY BUILDING VENTILATION SYSTEM MODIFICATIONS DEVIATION The existing safety-related filter trains do not include demisters The existing safety-related filter trains do not include HEPA filters after the absorber banks.

The' existing safety-related filter trains do not include heaters The existing safety-related filter trains are not pro-tected against tornadoes JUSTIFICATION FOR DEVIATION LOCA MODE OF OPERATION REFUELING ACCIDENT MODE OF OPERATION Moisture release is postulated not to exceed 4,800 cc/hr due to ECCS leakage.

This results in a relative humidity

• less than 85 percent.

See Item 3, below.

The release of carb'on fines from the absorbers to the environment is not part of the original design basis of of the station.

The omission of the filters has been reviewed and found not to be an unreviewed safety ques-t ion.

The acceptance criterion for the laboratory analysis of charcoal samples in 95 percent methyl iodide removal efficiency at a relative humidity of *less than 85 percent is calcul.ated on the following basis:

a.

Assuming 100 percent relative humidity outdoor air is supplied to ECCS equipment areas

b.

Taking credit for heat release from the minimum number of operat-ing ECCS equipment

c.

Assuming a maximum internal moisture release of 4,800 cc/hr due to ECCS leakage The probability of a LOCA followed by a tornado within 30 days is less than 10-7.

There is no potential for entrained water droplet in the exhaust air stream.

Same as for LOCA.

Charcoal samples tested to 95 per-cent methyl iodide removal efficien-cies at a relative humidity 85 percent, will exhibit methyl iodine removal efficiency in excess of 70 percent with no control of relative humidity.

The. filter system mitigates the consequences of the accident in two hours before the long term tornado could take place

• REGULATORY GUIDE ITEM 1.52 POSITION 5

C.2.f 6

C.2.j 7

C.2.1 8

C.3.c 9

C.3.c DEVIATION Each existing safety-related filter train has 36,000 cfm capacity.

The existing safety-related filter trains are not de-signed for'replacement as intact units or in a mini-mum number of segmented sections without removal of individual filter com-ponents.

The filter ductwork is de-signed to exhibit on test a leakage rate of approxi-mately l percent of system flow.

The existing prefilters do not meet UL Class l require-ments.

The existing prefilters do not have 45 percent atmos-pheric dust spot efficiency rating.

JUSTIFICATION FOR DEVIATION Attachment II Page 2 of 4 LOCA MODE OF OPERATION REFUELING ACCIDENT MODE OF OPERATION This nonconformance does not affect system safety function.

Cutting the ESF filter system into segments without revmoval of indi-vidual components exposes the local environment and the personal working in it to unncessary contamination.

When compc*nents are individually re-moved for packaging, shielding, and shipment, operating exposure is mini-mized.

After all components are re-moved and ~he housing has been washed down, it is then determined whether the housing has been satisfactorily decon-taminated for reuse or whether cutting for shipment and burial off site is required.

Since leakage is into the system, contamination of personnel is not a problem.

The combustible material contained in the prefilters is insignificant (less than 20 percent) in comparison with the charcoal in the absorbers.

The low efficiency prefilters merely shorten the life of the HEPA filters; they do not affect system safety function.

Same as for LOCA.

Same as for LOCA.

Same as for LOCA.

Same as for LOCA.

Same as for LOCA.

ITEM 10 11 12 13 REGULATORY GUIDE

l. 52 POSITION C.3.i C.3.k C.4.b C.5.c DEVIATION The 2 in. thick absorber beds are designed for an average residence time of 0.125 sec.

No decay heat removal system is provided.

No space is provided be-tween HEPA filter and absorber mounting frames for personnel access.

The acceptance criterion for in-place halogen test is 99 percent efficiency.

Attachmen.

Page 3 of 4 JUSTIFICATION FOR DEVIATION LOCA MODE OF OPERATION REFUELING ACCIDENT MODE OF OPERATION Laboratory analysis on charcoal samples is based on tests conducted at design residence time.

The total decay energy (integrated to infinity) and the decay heat generation rate of the iodines re-leased from 4,800 cc/hr of ECCS leakage is insufficient to raise the temperature at any point in the absorber bed to 2QO F, assuming:

a.

10 percent of the iodines in the ECCS leakage (at less than 212 F) becomes airborne, as per Standard Review Plan 15.6.5, Appendix B.

b, An initial absorber bed equilibr:l.um temperature of 125 F.

c.

Transient heat transfer and storage in the absorber bed is by conduction through a homogeneous medium.

The lack of access space between the HEPA filter and absorber mounting frame makes in-place testing less convenient. It does not affect the system safety function.

Dose calculation take credit for 90 percent particulate removal efficiency.

Therefore, the demonstration of 99 percent efficiency ensures that the required capability of filters is met or exceeded

• Same as for LOCA.

Same as for LOCA, except that the airborne iodine inventory is in accordance with Regulatory Guide 1.25.

Same as for LOCA.

Dose calculations take credit for 70 percent particulate removal efficiency, Therefore, the demon-stration of 99 percent efficiency ensures that the required capability of the filters is met or exceeded.

ITEM 14 REGULATORY GUIDE

1. 52 POSITION C.5.d DEVIATION The acceptance criterion for in-place test is 99 percent efficiency.

e Attachment II Page 4 of 4 JUSTIFICATION FOR DEVIATION LOCA MODE OF OPERATION REFUELING ACCIDENT MODE OF OPERATION Dose calculations take creidt for 90 percent removal efficiency for all species of iodine.

Therefore, the demonstration of 99 percent efficiency fore the in-place halogen test combined with the 95 percent methyl iodine re-moval efficiency for the laboratory test ensures that the required capability of the filters ia met* or exceeded.

Dose calculations take credit for 90 percent removal efficiency for all species of iodine.

Therefore, de-monstration of 99 percent efficiency for the in-place halogen test com-bined with the 95 percent methyl iodide removal efficiency for the laboratory test ensures that the re-quired capability of the filters is met or exceeded

• Attachment III Issue Date:

July 25, 1979 MODIFIED AUXILIARY BUILDING VENTILATION SYSTEM DESCRIPTION SURRY POWER STATION UNITS 1 AND 2 VIRGINIA ELECTRIC AND POWER COMPANY

J.O.No. 12846.13 1.14 TABLE OF CONTENTS

1. 17 1.0 1.1 1.1.1 1.1.2 1.1.3 1.1.4 1.1.5

---~J~1~6 1.1.7 1.1.a 1.. 1.9 1.2 1.3 1.3.1 1.3.2 1.3.3 1.3.4 1.3.5 1.3.6 1.4 1.5 2.0 2.1 2.1.1 2.1.1.1 2.1.1.2 2.1.1.3 2.1.1.. 4 2.1.1.;5

SUMMARY

SYSTEM DESIGN Detailed System Design Description Fuel Building Supply and Exhaust Ventilation Decontamination Building Supp1y and Exhaust Ventilation Unit 1 and Unit 2 Safeguards Building Supply and Exhaust Venti1ation Auxiliary Building Central Area Supply and Charging Pumps Exhaust Ventilation Auxiliary Building General Area Supply and Exhaust Ventilation

Co~tainm~n~ ~v.rge Suppl~ and_ Exha_ust

Ventilation Safety-Related Auxiliary Exhaust Filtration Nonsaf ety-Related Auxiliary Building Exhaust Filtration Design Conditions

1.

outdoors

2.

Indoors Arrangement Component Design Heating and Ventilating Units Exhaust Fans Safety-Related Auxiliary Exhaust Filtration Assemblies Nonsaf ety-Related Auxiliary Building Exhaust Filtration Ducts Dampers Instrumentation and Control Electrical Power Systems SYSTEM OPERATION Normal Operation Both Units on Line No Radiation Alarm in Any Exhaust System Radiation Alarm in Exhaust Stream 11G11 Radiation Alarm in Exhaust Streams 11G* and 9 F11 Radiation Alarm in Exhaust Streams 11G" 11 "F" and

• o*

Radiation Alarm in Other Exhaust Stream Combinations Unit 1 On Line and Unit 2 Off Line I

b-12846.13-6b 09/25/78 Page 1.20 1

2 2

2 2

3 4

5 8

8 8

9 10 10 11 12 12 13 13 13 13 14 14 14 14 15 16 18 19 20 083 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29 1.30 1.31 1.32 1.33

- 1_.34 1.35 1.36 1.37 1.38 1.39 1.40 1.41 1.48 1.49 1.50 1.51 1.52 1.53 1.54 1.55 1.56 1.57 1.58 1.59 2.2 2.3 2.4 2.5 2.6 2.1 2.8

-2.9 2.10 2.11 2.13

2.1.2.1 2.1.2.2.

2.1.2.:3 2.1.2.4 2.1.3 2.2 2.2.1 2.2.2 2.2.3 2.2.4 2.2.6 3.0 3.1 3.2 3~3 3.4 TABLE OF CONTENTS (CONT 'Dl Cooldown. and Purging of Unit 2 Refueling Unit 2 Misc. Maintenance on Unit 2 Following Refueling Misc. ~..a.intenance on Unit 2 Following Refueling with Radiation Activity in Exhaust Stream "F" Unit 1 Off Line and Unit 2 On Line Accident Operation Both Units On Line Followed by LOCA in Unit 1 Both Units On Line Fo1lowed by LOCA in Unit 2 Unit 1 On Line and Unit 2 Off Line Followed by LOCA in Unit 1 Unit 1 On Line and Unit 2 Refueling Followed by LOCA in Unit 1 unit.. *1 -on* Liile***ana.**uriit. 2-*R.e£ue1.l.ng Fciliowed.

by a Refueling Accident Inside Unit 2 Contaimnent or Fuel Building Unit 2 On Line and Unit 1 Off Line and/or Refueling SYSTEM FEATURES FOR POTENTIAL EMERGENCIES Loss of Nonsafety-Related Equipment Loss of Normal Power Loss of Station Compressed Air Single Failure of Ventilation Equipment II b-12846.13-6b 09/25/78 20 21 23 23 23 24 24 25 25 27 29 29 29 30 30 31 31 083 2.14 2.15 2.16 2.17 2.18 2.19 2.20 2.21 2.23 2.24 2.25 2.26 2.27 2.28 2_._2, 2.30 2.31 2.32 2.33 2.34 2.37 2.38 2.39 2.40 2.41

1.

SUMMARY

1.9 The auxiliary ventilation system consists of the following.* 1. 12 subsys~ems:

.1*

Fuel building supply and l*

Decontaminatiori building

3.

Unit 1

safeguards yentilation Unit 2

safeguards yentilation exhaust ventilation supply and exhaust building supply building supply ventilation and exhaust and exhaust 1.14 1.16 1.18 1.19 1.21 1.22

5.

Auxiliary building central area supply and charging pump 1.24 exhaust yentilation 1.25

""6.

~~--Auxiliary "thiild.Th~f -general yentilation area supply and Containment purge supply and exhaust ventilation exhaust 1.27 1.28 1.30 1*

~-

Safety-related fi_lters) auxiliary exhaust filtration (CAT I 2.2 2.3 2_.

Nonsafety-related auxiliary building exhaust !iltration 2.6 (CAT II filters)

,!he above exhaust streams are manifolded at the top floor of the au:x1liary building, discharged through a common ventilation vent and continuously monitored for radioactivity..!his release is in the wake of Unit 2 containment.

b-12846.13-Gc 10/02/78 083 2.8 2.. 8/1 2.9/1

2.

1*0 SYSTEM DESIGN 2.11 1*1 DETAILED SY STEM DESIGN DESCRIPTION 2.13 The

~ollowing design description is based on the flow diagram* 2.15 11448-FKS-24 included in this document.

The. scope of this 2.15/

document is to describe the m:>dified auxil.iary ventilation system design and operation.

1.1.1 Fuel Building Supply and EY.Jlaust Ventilation The fuel building ventilation exhaust rate of 35,500 cfm is based on inhibiting condensation, from the spent fuel storage pool with summer design temperatures to 140°F.

!he supply and exhaust ventilation subsystem is also designed to limit indoor design temperature to a minimum of 75°F in the winter and a maximum of 105°F in the summer.

2.17 2.19 2.20 2.21 2.22

-The~ ventil-at-ion---~system-- -is -designed with-a *larger exhaust flow - 2.24 ----

rate than supply flow rate to ~nsure only inward leakage.

2.25

!he air supply stream is filtered to help maintain the fuel pool water clarity. The ventilation air supply subsystem consists of an outdoor air intake without shutoff dampers; ~n air filtration unit (1-VS-FL-2),

a face and bypass

damper, heating coil (1.,...BS-E-2),

two supply fans

_{l-VS-F-6 and 1-VS-F-39),

an indicating flow meter, distribution ductwork,

dampers, and

,£Ontrol instrmnentation to supply 34,000 cfm.

This subsystem is Quality Category II, Quality Group D (CAT II)

• This subsystem is powered from the normal electric bus.

The ventilation exhaust subsystem is designated in this document as exhaust stream *F.*,!t consists of two 50 percent capacity exhaust fans (1-VS-F-7A&7B)

!Yld exhaust ductwork to the ventilation vent with a connection through isolation trip dampers to the CAT I filters.

Within the fuel building the exhaust ductwork is CAT II.

~e subsystem classification changes to CAT I at the penetration through the fue1 buil.ding wall..

The exhaust subsystem is powered from the no:rmal electric bus.

It draws air across the surface of the pool and exhausts 35,500 cfm from the fuel building and the waste gas compressor and surge drum room.

The exhaust air is monitored for radioactivity at the building exhaust duct.,!he air is exhausted outdoors through the ventilation vent which is also monitored.

1.1.2 Decontamination Building Supply and Exhaust Ventilation 2.27 2.28 2.29 2.30 3.1 3.3 3.4 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.. 13 3.14 3.15 3.19 3.20 The decontamination building ventilation subsystem is designed to 3.23 maintain a maxi.Ilrum-temperature of 120°F in storage spaces and 3.24 100°F in work spaces and a minimum of 50°F and 65°F in these areas during winter.

The ventilation system is designed with a

3.2E>

b-12846.13-Gc 10/02/78 083

3.

larger exhaust flow.rate than supply flow rate to ~nsure inward 3.27 leakage.

The decontamination building air supply subsystem consists of:

3.29 outdoor air intake without shutoff dampers and one heating and* 3.30 ventilating unit (1-VS-HV-5) which includes filter, face and bypass damper, heating coil and air supply

fan, as well as distribution ductwork and control instrmnentation.

This subsystem is CAT II. !his subsystem is powered from the normal electric bus.

It de1ivers 9.ooo cfm to the decontan>ination building. rrom the boron pump house 2,200 cfm infiltrates for. a*

total supply of 11,200 cfm.

4.1 4.2 4.3 4.4 4.4/1

'!"he ventilation exhaust subsystem is designated in this document

4. 6 as exhaust stream *n.* It consists of two 50 percent capacity

4. 7 exhaust fans (1-VS-F-56A&B), a ducted exhaust connection from the ultrasonic cleaning tanks complete with a

demister, high 4.8 efficiency filter. a~~--

-~ --~~~e_;-_

~an _ _!,-Y$-F:-~?LLda;x;p~;-s __ ang __. q.9_

• controT *i.nst:rumen:tatlon -arid-eXhaust ductwork to the ventilation 4. 10 vent with a connection through isolation trip dampers to the CAT I filters..

The whole is CAT II.

exhaust system with the exception of the exhaust fans The exhaust fans and associated dampers are CAT I.

The exhaust subsystem is powered from the noz:mal electric bus.

It draws 12,300 cfm from the entire decontamination building including 2,200 cfm in filtration from the boron J2llmP house into the decontamination building.

The exhaust air stream from the building is monitored for radioactivity and discharged through the ventilation vent which is also monitored.

1.1.3 Unit 1 and Unit 2 Safeguards Building Supply and EY..haust Ventilation 4.12 4.13 4.15 4.16 4.16/

4.18 4.19 4.23 4.24 For purposes of this system description the following space 4.26/

designations are used:

Safeguards Room:

§pray Pumps Room:

Containment Air The building enclosing the containment

!:ecircu1ation spray pump and the low head safety injection £UII!p The building enclosing the containment spray

pumps,

!:efueling water recirculation

pumps, and subsurface discharge J2umps Compressor Cubic1e: Se1f-explanatory b-12846.\\3-6c 10/02/78 083 4.26/

4.26/

4.26/

4.26/

4.26/

4.26/

4.26/

4.26/

Safeguards

~uilding:

4.

The entire enclosure consisting of :!:,he safeguards room, spray pumps

room, and.:

containment air corepressor cubicle

!he safeguards building ventilation subsystem is designed for a maxililum space temperature of 120°F in the summer with all safety-related equipment in operation and a minimum _2Pace temperature of GOOF in the winter.

The ventilation system is designed with a larger exhaust flow rate than supply flow rate to ~nsure inward leakage.

!he safeguards building air supply subsystem consists of an outdoor air intake without shutoff dampers and a

heating and ventilating unit (1-VS-HV-4 for Unit 1 and 2-VS-HV-4 for Unit 2) which includes filters, face and bypass dampers, heating coil and

fan, distribution ductwork and control instrumentation_..

The supply sUbsystert: is CAT II. powered from the normal electric bus.

It is powered from the normal electric bus.

The subsystem delivers a total of 16,000 cfm; !,000 cfm to the spray pump room and 12,000 c£m to the rest of the building.

The safeguards building exhaust subsystem is designated in this document as exhaust stream "SGl" J.nSG2" for Unit 2)

• It consists of two 50 percent capacity exhaust fans (1-VS-F-40A&B for Unit 1 and 2-VS-F-40A&B for Unit 2),

a ducted exhaust branch with isolation trip dampers for the -containment instrument air compressor cubicle, control instrumentation and exhaust ductwork to the 'ventilation vent with a connection through isolation trip dampers to the CAT I filters.

The exhaust flow rate of an SG stream at 12,000 cfm is based on the LOCA mode of operation with the isolation dampers to the air compressor cubicle duct closed.

A two-speed roof fan (1-VS-F-43 for Unit 1 and 2-VS-F-43 for Unit 2) exhausts the balance of the air from the spray pump room.

Each exhaust subsystem is CAT I except for the air exhaust branch duct for the containment instrmnent air compressor cubicle and

!:,he roof exhaust fan.

The exhaust subsystem is powered from the emergency electric bus

~d the roof fan is connected to the normal electric bus.

Exhaust stream SG1 (SG2) is monitored for radioactivity,Erior to release.

1.1.4 Auxiliary Building Central Area Supply and Charging Pumps Exhaust Ventilation The auxiliary building ventilation subsystem is designed to liir.it the maximum temperature ~ normal.ly occupied spaces to 105°F and in normal.ly unoccupied machinery spaces to 1200F.

b-12846.13-6c 10/02/78 083 4.. 26/

4.26/

5.14 5.. 15 5.15/

5.17 5.18 5.20 5.21 5.22 5.23 5.23/

5.24 5.26 5.28 5.29 5.30 6.1 6o.2 6.3 6.5 6.6 6.9 6.10 6.12 6.13 6.15 6.21 6.22 6.25 6.25/

s.

The ventilation equip~ent is designed with a larger exhaust flow rate than supply flow rate to ensure inward leakage.

6.29 6.30 The auxiliary building air supply subsystems for both the central* 7.2 and ge~eral areas are £0IDIDOn and identical.

They consist of-7.3 outdoor air intakes without shutoff da:rr.~"2rs and two heating and ventilating units (1-VS-EV-1A&B) which include: filter, face and

.£ypass daII'.per, heating coil and air supply fans, distribution 7.4 ductwork and control instrumentation.

These supply subsystems are from the normal electric bus.

total of 62,000 cfm (31,000 building.

classified CAT II ~nd are powered The system is rated to deliver a

cfm each unit) to the auxiliary

,!he charging pump exhaust ventilation subsystem designated in this document as exhaust stream new consists of

_:!;WO 100 percent capacity exhaust fans (1-VS-F-9A&B), control instrumentation ~nd exhaust ductwork to-the ventilation vent-with a

"connection through isolation dampers to the CAT I filters.

The subsystem has two position motor-operated dampers on the exhaust duct frore each charging pump cubicle.

!he damper motors from the pump cubicles are interconnected with the charging pump motor to open when the pump operates and close when the pump stops *

!he "C" stream also exhausts air from the cubicles of the seal water and nonregenerative heat exchangers, purification, and sump pumps, and high and low level waste drain filters.

The maxinnm_

design exhaust rate of the °C 11 stream of 22,000 cfm is based on the LOCA mode of operation when a

maximum of 3

charging pumps are postulated to operate:

2 charging pumps on the unit ~equiring high head safety injection and one charging pwr.p for the other unit.

During normal station operation the "C" stream exhaust is 15,500 cfm.

The exhaust subsystem is classified CAT I and powered from the emergency electric bus.

The exhaust air stream from the building is continuously monitored for radioactivity.

1.1.s Auxiliary Building General Area Supply and Exhaust Ventilation 7.7 7.7/1 7.8 7.10 7.11 7.12

7. 13 7.15 7.16/

7.16/

7.17 7.18 7.19 7.19/

7.21 1.22 7.27 7.28 The general area Section 1.1.4.

supply ventilation was described in 8.2 The general area exhaust ventilation subsystem is designated in 8.4 this document as exhaust stream *G* and consists of ductwork, two 8.5 50 percent capacity exhaust fans (1-VS-F-BA&B) control instrumentation and exhaust ductwork to the ventilation vent with 8.6 a connection through isolation trip dampers to tlie CAT II filter.

Roof exhaust fan (1-VS-F-10) may be used intermittently, as 8.8 required, to exhaust the cement storage and drumrring areas.

b-12846.13-0c 10/02/78 083

6.

Exhaust stream *G* is classified CAT II except for the exhaust fans and dampers which are CAT I.

The exhaust subsystem *G" and the roof fan are powered from the normal electric bus.

Exhaust stream G and the roof fan exhaust flow rates are 47,300 c£m and 2,soo,:respectively.

8.10 8.11 8.12 The exhaust air stream "G* from the building is monitored for 8.14 radioactivity during discharge.

1.1.6 Containment Purge Supply and Exhaust Ventilation The purge system is designed for one air change of a containment per hour and to maintain a minimum of 600F inside the containment.

~otor-operated butterfly valves are instal.led on both sides of the containment penetrations for isolation.

A branch connection fitted with an intake filter al'.!~ __ ll!9!=:0r::0:eer~t-~_ l;?!;~1;,~~ly_ y~ve is iifstalle_d ___ iii __ tne !upply "stream -bet.ween t.he outer isolation valve and the containment bomidary.

This connection will enable the containment to be brought to atmospheric pressure Erior to operation of the purge supply and exhaust subsystems.

Containment purge supply subsystem consists of a tilter, face and bypass damper and heating coil.11-HS-E-1); two supply fans rated at 14,500 cfm each (1-VS-F-4A and B), distribution ductwork, controls, and instrumentation.

This supply air stream is CAT II, except for the containment isolation butterfly valves which are Cb.T I.

This subsystem is powered from the norxral electric bus.

!he purge exhaust ventilation stream rated at 30,000 cfre is designated in this docmnent as exhaust stream

• RC1" and "RC2",

for Unit 1 s_nd Unit 2, respectively.

The stream consists of isolation

valves, instrumentation, and eY.haust ductwork connecting to the CAT I filters.

~he exhaust streams *RC1" and *RC2" are classified CAT II inside containment, and CAT I outside containment, and CAT I Group B between s_nd including the containment isolation valves.

1.1.7 Safety-Related Auxiliary Exhaust Filtration (CAT I Filters)

!he CAT I filter subsystem is designed to provide for radioactive iodine and methyl iodide removal from the exhaust air streair.s F,

n.

SG1, SG2, C,

and RC1 or RC2 described above.

The filter provides for: (1) uniform air distribution within +/-20 percent of average flow across the face of the filter, (2) 99.0 percent particulate renoval efficiency, and (3) 1.0 percent halogen leakage S,Dd 95 percent methyl iodide removal efficiency with b-12846.13-6c 10/02/78 083 8.18 8.20 8.20/

8.24 8.25 8.26 8.26/

8.27.

8.29 8.30 9.2 9.3 9.5 9.6/1 9.8 9.8/1 9.9 9.12 9.12/

9.14 9.15 9.18 9.19 9.20

7.

influent air at maximum of 125°F, BS percent rel.ative humidity 9.21 and 0._125 seconds residence time.

The CAT I filter subsystem consists of an inlet header, redundant**

filter trains (1-VS-FL-3A&B) with prefilter, HEPA filter and*

charrnal adsorber, exhaust :fans

( 1-VS-F-58A and B), dampers, control instrumentation and exhaust ductwork to the continuously monitored venti.1ation vent.

~he capacity of each fil.ter train and fan (36,000 cfm} wi11 meet the LOCA mode of QPeration when the *c" and "SG" streams at 22,000 and 12,000 cfm, respective1y, are diverted through the filters to treat ECCS 1eakage postulated to have evaporated within the spaces served by these two exhaust streams.

The 2,000 cfm excess fi1ter capacity is an allowance for damper leakage.

With periodic taken for 90 conditions.

verification of percent iodine filters removal perfoDDallce, credit is efficiency for LOCA The safety-related auxi1iary exhaust filtration subsystem is classified CAT I.

The redundant exhaust fans, 1-VS-F-SBA and B, are powered trom -the Unit 1 orange and the Unit 2 orange

.§Ilergency buses, respectively.

Provisions have been made for supplying an a1ternate source of*

power from Unit 2 purple bus to ~an 1-VS-F-5BA to prevent forced Unit 2 shutdown due to the loss of

• CAT I filter subsystem redundancy during extended outage of Unit 1 orange diesel generator.

Provisions have also been made for supply.ing an alternate source of power from Unit 1 purple bus to fan 1-VS-F-58B to prevent forced Unit 1 shutdown due to the loss of CAT I filter !:edundancy during extended outage of Unit 2 orange diesel generator.

1.1.8 Nonsafety-Related Auxiliary Building Exhaust Filtration (CAT II Filter)

The CAT II filter subsystem is designed to provide for radioactive iodine and methyl iodide removal from exhaust stream

• G."

.§pecifically, it provides for: (1) uniform air distribution within +/-20 percent of average fl.ow across the face of the filter, (2) 99.95 percent particulate removal efficiency, and (3) O.OS percent halogen leakage and 90 percent methyl iodide removal efficiency with influent air at a maximum of 125oF, 70 percent relative humidity, and 0.25 seconds residence time.

~he CAT II filter subsystem consists of a

filter assembly (1-VS-FL-14) containing prefilter, EEPA fi1ter charcoal adsorber, air exhaust fan (1-VS-F-59), dampers, control instrumentation and

.exhaust f!_uctwork with isolation trip dampers to the venti1ation vent.

The capacity of the filter assembly and fan (48,000 cfm) b-12846.13-6c 10/02/78 083 9.23 9.24 9.25 9.26 9.27 9.28 9.28/

10.1 10.9 10.10 10.11 10.13 10.14 10.15 10.17 10.18 10.19 10.23 10.24 10.27 10.28 10.30 11.1 11.2 11.3 11.5 11.6 11.7 11.8

B.

is based on the mode which routes the *G* air stream (47,300 cfm) 11.9 througp the filter.

The nonsafety-related auxiliary builCing exhaust filtration*

subsys:tem is classified CAT II up to isolation trip dampers which-connect to the CAT I breeching at the ventilation vent.

The subsystem fans are powered from the normal bus.

1.1.9 Desian Conditions

1. outdoors:

Summer dry bulb,oF wet bul.b,oF dew point,oF Winter dry bulb,OF

2. Indoors:

Fuel Building 93 78 73 10 With a 140°F fuel pool water temperature 75°F minimum temperature 1osoF maximum and 790F dew point Decontamination Building 120°F maximum, sooF m:inimwn for storage and tank spaces 100°F maximum, 6SOF minimum for work spaces Safeguards Building 120°F maximum in pump cubicles S0°F minimum Auxiliary Building 120°F maximum, S0°F minimum nuclear auxiliary equipment cubicles 105°F maximum, 50°F m.uumum for the balance of the building and ventilation equipment room Reactor Containment - shut down conditions 60°F minimum with purging system in operation J..2 ARRANGEMENT 11.11 11.12 11.13 12.15 12.18 12.20 12.21 12.22 12.23 12.27 12.29 13.1 13.2 13.3 13.7 13.9 13.10 13.14

13. 16 13.17 13.21 13.23 13.24 13.28 13.29 14.3 14.5 14.11

!:he arrangement of the system described.above is shown on the 14.13 drawings (later)

• b-1284o.13-6c 10/02/78 083

9.

§pecial design features of the individual subsystems are as 14.16 fol.lo~s:

~-

Isolation trip dampers

.. 14.18

b.

1'.he fuel building (F), decontamination building (D), and purge (RC)

~xhaust streams connect to the CAT I filter subsystem through 2.ir-operated isolation trip dampers to ensure the isolation of these streams from the filter

!ollowing LOCA.

For a

refueling accident, automatic opening of the F and RC isolation trip dampers is not required since they are opened £rior to the start of refueling operations and designed to remain open for two hours which is the postulated duration for mitigating the consequences of a refueling accident (NRC Re9ul.atory Guide 1.25, position C.1.i.).

The charging pumps (C) and saf eguarcs (SG 1 or SG2) exhaust streams are each"connected to-the CAT-I filter subsystem through two isolation trip da.n:.pers in parallel to ensure the,Qpening of these streams to the filters fol.lowing a

LOCA.

Unlike all the other isolation trip dampers, the safeguards dampers are motor-operated since only the *SG" stream at the unit with LOCA is to remain open and the 11SG" stream of the unit without a LOCA is to remajn closed for an extended period following a LOCA when compressed air is not available.

All exhaust streams which bypass the CAT I filter and connect to the breaching 2.t ventilation vent are provided with air-operated isolation trip dampers to ensure closure following a LOCh..

Redundant isolation trip dampers safety class changes in ductwork maintenance of design air flows 2.CCident conditions.

Isolation dampers are provided at all to ensure the during and after Manual dampers for isolation of testing.

DMP60A, DMP60B, and D.MP61J are provided the filters during maintenance and Manual dampers

DMP61A, DMP61B,

DMP62, and DMP63 are provided to facilitate operation during the construction phase of the ventilation system modification.

1'.hese dampers have no function in the final modified system and will be locked in the open. or closed position as shown.Q.n the flow diagram.

b-12846.13-6c 10/02/78 083 14.19 14.21 14.23 14.25-14.26 14.2'7 14.29 14.30 15.1 15.2 15.3 15.3; 15.5 15.6 15.7 15.91 15.1L 15.1{

15.1~

15.2(

15.2*

15.2:

15.2:

£*

10.

Air distribution within filters The in1et and outlet plenmr.s of the CAT I filters are

£rovided with subpl.enums of approximately the same**

dimensions as the filter banks.

Perforated sheet metal.

in the inlet and outlet subplenums-reduce entering and leaving air turbulence to provide uniform air distribution through the filter banks to n:eet technical specification requirements.

Charcoal fil.ter test canister arrangement A set of 18 test canisters is insta11ed across the adsorber bank of each CAT I filter train to permit charcoal sampling for Eeriodic lah:>ratory analysis without breaking the adsorber/frame seal. !he canisters provide an air flow path in parallel to the main adsorbers and are removable f.rom. the out1et plenum.

j_.3 COMPONENT DESIGN

!he following description covers only principal design features of major air supply and exhaust system components.

Eor additional information, refer to the component specifications.

j_.3.1 Heating and Ventilating Units 15.26 15.2.8 15.29 16.2 16.3 16.3/

16.6 16.9 16.11 16.12 16.15 16.17 16.18 16.22 The air is supplied to each building by heating and ventilating 16.24 units.. which are listed in the following table:

16.24 Bui1ding Fuel Decon.

Heating and Ventilation Supply Unit Mark No.

None (Built up Unit) 1-VS-HV-5 Safeguards 2-VS-BV-4 Safeguards 1-VS-HV-4 Auxiliary 1-VS-HV-1A 1-VS~-1B b-12846.13-6c Component Mark No.

1-VS-FL-2 1-HS-E-2 1-VS-F-6 1-VS-F-39 None (Factory Assembled Unit)

None None None None 10/02/78 Air Supply

capacity, Cfm 29,000 5,000 9,000 16,000 16,000 31,000 31,000

Pressure, In w.G.

2.75 s.oo 2.25 2.25 2.25 Later Later 083 17.15 17.15 17.15 17.15 17.2()

17.20 17.20 17 *.20 17.24 17.24 17.24 17.24 17.27 17.28 18.1 18.2

Buildina Contain-ment Purge Heating and Ventilation Supply Unit Mark No.

None 1.3.2 Exhaust Fans

11.

Component Mark No.

1-HS-E-1 1-VS-F-4A 1-VS-F-4B Air Supply

Capacity, Cfm 14,500 14,500 Pressure,**

In W.G.

s.o s.o 18.5 18.6 18.6/

18.14

!he filter bypass exhaust fans which discharge directly to the 18.16 ventilation vent as well as the filtered exhaust-fans are 18.17 nonoverloading, centrifugal type-with single speed motors.

,!he capacity and static pressure are as follows:

18.20 System no* Stream No. of Fans 2

2 "SG2* Stream 2

• sG1* Stream 2

• c* Stream 2

• G* Stream 2

Safety-related Filters 2

Nonsafety Filter 1

Equip.

No.

1-VS-F-7A 1-VS-F-7B 1-VS-F-56A 1-VS-F-56B 2-VS-F-40A 2-VS-F-40B 1-VS-F-40A 1-VS-F-40B 1-VS-F-9A 1-VS-F-9B 1-VS-F-SA 1-VS-F-SB 1-VS-F-58A 1-VS-F-58B 1-VS-F-59 Capacity

Each, Cfm 17,750 6,150 6,000 6,000 15,500*

23,650*

36,000 48,000 Pressure in In, W.G.

9.25 5.5 s.s 5.5 9.0 9.0 Later Later Inlet Vanes Yes No No No Yes Yes Yes Yes

• Original design capacity - fan capacity to be reduced during system balancing.

b-12846.13-6c 10/02/78 083 18.25 18.26 18.27 18.2~

18.30 19.13 19.14 19.18 19.19 19.23 19.24 19.28 19.29 20.3 20.4 20.8 20.9 20.12 20.20 20.21

12.

1.3.3

• Safety-Related Auxiliary Exhaust Filtration *Asse!I'.blies (CAT I Filters) 20.26 20.27 The safety-related auxiliary building filtration assemblies* 20.30

.£0nsist of the following ~ections: prefilter, HEPA

filter, and 21.2 charcoal adsorber.

~refilters are disposable type, faced with screen and bound with metal edges.

~he filtering material is glass fiber, coated with an adhesive and is temperature resistant to 2sooF.

~ilter efficiency is not less than 10 percent based on National Bureau of Standards Discoloration Test Method with Atmospheric Dust.

The initial clean filter air resistance does not exceed 0.12 in.-W.G. (+/-10 percent) at 300 fpm face velocity.

High Efficiency Particulate Air fHEPA) filters meet the construction, materials, *test.

• and gualification requirements of ANSI Standard N509-1976, as well as military specification

~L-F--005106BD, "Filter, Particul.ate, High Efficiency Fire Resistant" and have fiberglass media

.£Onforming to the requirements of military specification.MIL-F-1079D, "Filter Medium, Fire Resistant, Bigh Efficiency.

Charcoal adsorbers are tray type filled with new adsorbent charcoal meeting the Eequirements of ANSI 509-1976, Table 5-1, except that the acceptance criterion of test 5.a for ~ethyl iodide removal efficiency is 98 percent at a residence time of 0.125 sec.

The acceptance samples of used efficiency at residence time.

criterion for periodic retest of representative charcoal is 95 percent methyl iodide removal 125°F, 80 percent relative humidity and o.125 sec 21.5 21.6 21.7 21.9 21.10 21.11 21.13 21.14 21.15 21.10 21.17 21.19 21.20 21.20 21.24 21.25 The inlet and outlet Sketch 11448-BKS-10.

air straighteners are shown on 21.27 1.3.4 Nonsafety-Related Auxiliary Building Exhaust Filtration fCAT II Filter)

,!he nonsafety-related auxiliary building filtration assembly is ~

shop-fabricated, skid-mounted unit consisting of the following sections: Erefilter, HEPA filter, and charcoal adsorber.

Prefilters are replaceable type, surface dzy type media with

'iiiinimum 80 percent efficiency as determined

.£y the ASHRAE Standard 52 method.

~edia are moisture resistant.

HEPA filters meet the construction, materials, test, and qualifi-cation reauirements of ANSI Standard NS09-1976, as well as military iPeci£ication MI~F-00510680, "Filter, Particulate, High b-12846.13-6c 10/02/78 083 22.1 22.2 22.6 22.7 22.10 22.11 22.12 22.14 22.15 22.16

13.

Effici-ency, Fire Resistant" and have fiberglass media conforlti.ng 22.-17 to the requirements of military specification t_1IL-F-1079B,. 22.18 "Filte_:I:- Medium, Fire Resistant, High Efficiency.*

Charcoal adsorbers are fi1led with new adsorbent charcoal meeting the requirements of Reg Guide 1.140, Table 1.

The acceptance criterion for periodic retest of representative samples of used charcoal is in accordance with Reg Guide 1.140, Table 2.

j.3.5 Ducts 22.20 22.20 22.20.

22.23 1?0nsafety-related ducts and supports are constructed in 22.25 accordance with the applicable SMACNA Standards.

Ducts and supports for the up~aded. saf ety-re1ated systems are-designed in *accordance with the Specification

entitled,

• Installation of Ventilation and Air Conditioning,*

~nd the

• Technical Guideline (Stone Webster)

EMTG-11-A dated December 10,

1976, entitled "Design of Category I Duct Supports for Seismic Installations.*

22.28 22.29 22.30 23.l j.3.6 Dampers 23.4 The design pressure for all dampers equals fan shutoff pressure.

23.6 The design leakage differential pressure for dampers is as 23.9 follows:

AOD-VS-105, 205, 109, and 110 AOD-VS-102, 104, 106, 206, and 108 AOD-VS-101, 103, 107, and 111 MOD-VS-100, 101, 200, 201 1-VS-DMP-60, 61, 62, 63, and 64 2* W.G.

10* W.G.

8 11 w.G.

8 11 W.G.

10" W.G.

23.12 23.13 23.14 23.15

23. 16 All dampers are heavy-duty, opposed blade, Leakage Class II as 23.19 classified in ANSI N509.

1*4 INSTRUMENTATION AND CONTROL 23.22 Refer to logic and functional control diagrams to supplement the 23.24 design description below.

~Later>

23.27

_!.5 ELECTRICAL POWER SYSTEMS 23.29 Electrical power is provided to the COD!ponents of the auxiliary 23.30 ventilation system as described in Section 1.1 of this

~ecification.

23.30 b-12846.13-6c 10/02/78 083

14.

Those.components which are CAT I will be powered from the station 23.3Q emergency buses.

[:11 other system components wi11 be powered.* 23.3C from the station nonna1 buses.

2.0 SYSTEM OPERATION 24.2 2.1 NORMAL OPERATION 24.4 2.1.1 Both Units On Line 24.6

.£.1.1.1 No Radiation Alarm in Any Exhaust Stream 24.8 During this mode of station operation, the ventilation system is

~1igned to operate as follows:

24.10 24.11

a.

£*

Fuel building 24.15 The supply subsystem delivers 34,000 cfm 24.17 The exhaust stream *F* is discharged at the rate of 24.20*

35,500 cfm,:E;hrough the ventilation vent by

£ans 24.21 1-VS-F-7A and B.

Decontamination building The supply subsystem supplies a total of 9,000 cfm.

Exhaust stream 11D* is discharged at the rate of 12,300 cfm through the ventilation vent by fan~

1-VS-F-56A and B.

Unit 1 safeguards building The supply subsystem delivers 16,000 cfm.

Exhaust stream *SG1" is discharged directly through the ventilation vent by fans 1-VS-F-40A and B with 1,000 cfm drawn from the containment air compressor cubicle and approximately 11,000 cfm from the safeguards room.

24.211 24.2i

'1 24.30 25.1 25.4 25.7 25.10 25.11 25.12 25.13 Roof fan 1-VS-F-43 exhausts 4,000 spray £ump room.

cfm from the 25.15 25.16 Unit 2 safeguards building 25.19 The ventilation system operation for this building is 25.22 identical to that of Unit 1.

b-12846.13-oc 10/02/78 083

15.

Auxiliary building The supply subsystem delivers 62,000 c£m.

Exhaust stream "G" is discharged at the rate of 47,300 cfm directly through the ventilation vent by fans 1-VS-F-BA and B.

Exhaust stream ac*

draws 15,500 cfm (if two charging pumps are in operation) or 22.000 cfm (if three charging pumps are in operation) by tan 1-VS-F-9A or B and is discharged directly throuqh the ventilation vent.

25.25 25.28 26.1 26.2 26.5 26.6 26.7 Roof fan 1-VS-F-10 exhausts 2,500 cfm if required.

26.9 26.10 f_.

Reactor containment purge This subsystem is not in operation.

g.

CAT I filter This subsystem is not in operation.

h.

CAT II filter This subsystem is not in operation.

2.1.1.2 Radiation Alarm in Exhaust Stream *G"

!!f>on detection and alann of radiation activity in exhaust stream MG,* this one is manually diverted through the CAT II filter subsystem 2_11d the ventilation system operates as follows:

.2.*

Fuel building The supply subsystem delivers 34,000 cfm.

Exhaust stream "F" is discharged at the 35.500 c:fm directly through the ventilation fans 1-VS-F-7A and B.

b.

Decontamination building The supply subsystem delivers 9,000 cfm.

b-12846.13-6c Exhaust stream "D" is discharged at the 12,300 cfm directly through the ventilation fans 1-VS-F-56A and B.

10/02/78 rate of vent by rate of vent by 083 26.13 26.15 26.18 26.20 26.23 26.25 26.29 21.1 27.2 27.4 27.7 27.9/

27.12 27.13 27.16 27.19 27.22 27.23

16.

£ *.

Unit 1 safeguards building 27.26 27.29

~-

The supply subsystem delivers 16,000 cfm.

Exhaust stream *sG1* is discharged directly through the yentilation vent by fans 1-VS-F-40A and B with 1,000 cfm drawn from the containment air compressor cubicle and approximately 11,000 cfm from the

~a£ eguards room.

2&.2 28.3 28.4 28.5 Roof fan 1-VS-F-43 exhausts 4,000 spray 2ump room.

cfm from the 28.7 28.8 Unit 2 safeguards building 28.11 The ventil.ation system operation for this building is 28.14 identical to that of Unit 1.

Auxiliary building 28.17 The supply subsystems del.iver ~2,000 cfm.

28.20 Fans 1-VS-F-SA and B

are stopped, and exhaust 28.23 stream *G11 at the rate of 47,-300 cfm is diverted to 28.24 the CAT II filter subsystem as described below.

Exhaust stream *c* draws.15,500 cfm (if two 28.27 charging pumps are in operation) or 22,000 cfm 1if 28.28 three charging pumps are in operation) by fan 1-VS-F-9A or B and is discharged directly through

~he ventilation vent.

Roof fan required.

1-VS-F-10A exhausts 2,500

cfm, 28.29 if 29.1 29.2

f.

Reactor containment purge 29.5

!his subsystem is not in operation.

29.7 S*

CAT I filter 29.10 Ibis subsystem is not in operation.

29.12

h.

CAT II filter 29.15 Exhaust fan 1-VS-F-59 draws the *G* stream at the rate 29.17 of 47,300 cfm ~hrough the filter.

29.18 b-12846.13-6c 10/02/78 083

17.

£.1.1-3 Radiation Al.arm in Exhaust Streams *GM and "F" yPon detection and alarm of radiation activity in exhaust**

strea.Ir(s *G" and *F,".§_tream "G" is manually diverted through the*

CAT II filter subsystem, the *F*

stream is manually diverted through the CAT I fil.ter subsystem., and the yentilation system operates as follows:

s_.

Fuel building The supply subsystem delivers 34,000 cfm.

Exhaust fans 1-VS-F-7A and B are stopped, haust stream *F" is diverted to the CAT I subsystem as described below.

and ex-filter

b.

Decontamination building

£*

The supply subsystem delivers 9,000 cfm.

Exhaust stream "D" is discharged at the 12,300 cfm directly through the ventilation fans 1-VS-F-Sf>A and B.

Unit 1 safeguards building The supply subsystem delivers.16,000 cfm.

rate of vent by Exhaust stream *sG1* is discharged directly through the yentilation vent by fans 1-VS-F-40A and B with 1,000 cfm drawn from the containment air compressor cubicle and approximately 11,000 cfm from the

.§_af eguards room.

29.22 29.24 2~.25 29.27 29.28 30.1 30.4 30.7 30.8 30.11 30.14 30.17 30.17 30.21 30.. 24 30.27 30.28 30.29 30.30 Roof fan 1-VS-F-43 exhausts 4,000 spray E,ump room.

cfm from the 31.2 31.3 Unit 2 safeguards building 31.b The ventilation system operation for this building is 31.9 identical to that of Unit 1.

Auxiliary building The supply subsystem delivers 62,000 cfm.

- The supply subsystem delivers 62,000 cfm.

b-12846.13-6c Fans 1-VS-F-8A and B are stopped and exhaust.§_tream

• G* at 47,300 cfm is diverted to the CAT II filter subsystem as described below.

10/02/78 083 31.12 31.15 31.19 31.1~

£i*

h*

18.

Exhaust stream "C" draws 15,.500 cfm (if two 31.22 charging pumps are in operation) or 22,.000 cfm (i~

31.2~

three charging pumps are in operation) by fan 1-VS-F-9A or B ~nd is discharged directly through*

31.2~

the ventilation vent.

Roof fan 1-VS-F-10 exhausts 2,.500 cfm if required.

31.26 Reactor containment purge This subsystem is not in operation.

CAT I. filter gamper AOD-VS-101 is opened,. and exhaust fan J.-VS-F-58A or B is operated to draw the *F" stream through filter 1-VS-FL-3A or B,. respectively.

The exhaust flow rate of the "F" s_tream is automatica1ly controlled at 35,500 cfm.

CAT II filter 31.29 32.1 32.4 32.7 32.9 32.10 32.13 Exhaust fan 1-VS-F-59 is operated to draw the *G" stream 32.15 at a rate of 47,.300 cfm through the filter.

2.1.1.4 Radiation Alarm in Exhaust Streams "G," *F,* and *nn 32.19

!!Pen detection and alarm of radiation activity in exhaust streams

• G,* *F," and *n,. 11 stream "G* is manua1ly diverted through the CAT II !ilter subsystem,.

the "F* and "D" streams are manually diverted through the CAT I filter subsystem, EFd the ventilation system operates as follows:

32.21 32.22 32.24 32.25

~-

Fuel building 32.28 The supply subsystem delivers 34,000 cfm.

32.30 Exhaust fans 1-VS-F-7A and B are stopped, and 33.4 exhaust stream "F* is diverted to the CAT I filter 33.5 subsystem as described below.

Decontamination building 33.8 The supply subsystem delivers 9,000 c:tm.

33.11 Exhaust fans 1-VS-F-56A and B are stopped,. and 33.14 exhaust stream "D* at a rate of 12,300 cfm is 33.15 diverted-to the CAT I filter subsystem as described below.

b-12846.13-6c 10/02/78 083

£*.

g.

e.

f.

g.

19.

Unit 1 safeguards building The supply subsystem delivers 16,000 cfm.

Exhaust stream "SG1" is discharged direct1y through the yentilation vent by fans 1-VS-F-40A and B with 1,000 cfm drawn from the containment air compressor cubicle and approximately 11,000 cfm from the

.2_af eguards room.

33.18 33.21 33.24 33.25 33.26 33.27 Roof fan 1-VS-F-43 exhausts 4,000 cfm from the 33.29 spray £UitP room.

33.30 Unit 2 safeguards building The ventilation system operation for this building is 34.6 identical to that of Unit 1.

Auxiliary building 34.~

The supply subsystems deliver 62,000 c:fII!.

34.12 Fans 1-VS-F-SA and B

are stopped, and exhaust 34.15 stream "G" at a rate of 47,300 cfm is diverted to 34.16 the CAT II filter subsystem. as described below.

Exhaust stream "C"

draws 15,500 cfm (if two 34.19 charging pumps are in operation) or 22,uOO cfm

~if 34.20 three charging pumps are in operation) by fan 1-VS-F-9A or B and is discharged girectly through 34.21 the ventilation vent.

Roof fan 1-vs-F*-10A

,;:equired.

Reactor contaimr.ent purge exhausts 2,SuO

cfm, if 34.23 34.23 34.26 This system is not in operation.

34.28 CAT I filter 35.2 Dampers AOD-VS-101 and AOD-VS-103A and B are opened ~nd 35.5 exhaust fans 1-VS-F-SBA and B are operated to draw

~e 35.7 11F*

and

• nn streams through filters 1-VS-FI-3.A and B.

The exhaust flow rates of the *F*

and "D" stream are 35.8 automatically controlled at a

rate of 35,500 and 12,300 cfm, respectively.

b-12846.13-6c 10/02/78 083

20.

h-CAT II filter 35.11 The exhaust fan 1-VS-F-59 draws the *G 11 stream ~ta rate 35.14 of 47.300 cfm through the filter.

2.1.1.5 Radiation A1arm in Other Exhaust Stream Combinations In other combinations of radiation in exhaust streams "F," "D,"

nsG1,u ~SG2," and nc,* the ventilation system operation remains similar to that described above.

Any three-stream combination may be filtered simultaneously by the CAT I filter subsystem.

'Any four-stream con:bination n:.ay also be filtered provided *F*

and *en are not the two of the four contaminated streams.

All five streams cannot be filtered simultaneously.

If "F,ii *c,u and two other streams or all five streams are diverted through the CAT I filter subsystem, the capacity of the _filter trains will be exceeded resulting in degraded filter performance as ~ell as reduced exhaust flow rate.

The reduced exhaust flow rate wi11 pressurize the buildings and result in exfiltration of contaminated air from the buildings to outdoors and adjacent areas.

1.1.2 Unit 1 On Line and Unit 2 Off Line 1.1.2.1 Cooldown and Purainq of Unit 2 During this mode of station operation, the ventilation system is aligned to operate as follows:

~-

Fuel building The supply subsystem delivers 34,000 cfm.

Exhaust stream *F* is discharged at a

12,300 cfm directly through the ventilation fans 1-VS-F-7A and B.

b.

Decontamination building The supply subsystem delivers 9,000 cfm.

Exhaust stream 11D*

is discharged at a 12,300 cf:m directly through the ventilation fans 1-VS-F-56A and B *

.£*

Unit 1 safeguards building The supply subsystem delivers 16,000 c£m.

b-12846.13-Gc 10/02/78 rate of vent by rate. of vent by 083 35.17 35.19 35.20 35.23 35.24 35.25 35.26 35.2/

35.28 35.2~

35.30 36.3 36.5 36.7 36.8 36.12 36.15 36.17 36.18 36.~1 36.24 36.27 36.28 37.1 37.4

f.

S*

21.

Exhaust stream "SG1a is discharged directly through j:he ventilation vent by fans 1-VS-F-JJOA and B with*

1,000 cfm drawn from the containment air compressor cubicle and approximately 11,000 cfm from the*

§.af eguards room.

37.7 37.8 37.9 37.10 Rex>f fan 1-VS-F-43 exhausts 4,000 spray E,ump room.

cfm from the 37.12 37.13 Unit 2 safeguards building 37.16 The ventilation system operation for this building is 37.19 identical to that of Unit 1.

AuXiliary building The supply subsystem delivers 62,000 cfm.

Exhaust stream *G*

is rel.eased at the rate of 47,300 cfm directly through the ventilation vent by fans 1-VS-F-SA and B.

If all the charging pumps of Unit 2 have been shut down, then one of the MOD-VS-101 or MOD-VS-201 dampers in the cubicle of a nonoperating charging pump is manually opened.

This open

damper, together with the open damper of an operating charging pump of Unit 1, allows stream 11c* to be exhausted at a rate of 15,500 c£Ir.

through the ventilation vent by fans 1-VS-F-9A and B,

thus preventing the pressurization of the auxiliary*

building.

37.22 37.25 37.29.

38.1 38.2 38.2/

38.3 38.4 38.5 Roof fan 1-VS-F-10A

~equired *.

exhausts 2,500

cfm, if 38.1 38.7/

Reactor containment purge 38.10 The supply subsystem delivers 29,000 cfm j:o Unit 2 38.13 containment.

Exhaust stream *Rc2* is diverted to the CAT I 38.16 filter §.ubsystem as described below.

38.17 CAT I filter Damper AOD-VS-111 is opened and exhaust fan 1-VS-F-58A 2_r B draws the *RC2" strea.n: through the filter train 1-VS-FL-3A or B, respectively.

_!he exhaust fl.ow rate of the "RC2" stream is automatically control.led at a rate of 30,000 cfm.

38.20 38.22 38.25 38.26 b-12846.13-bc 10/02/78 083

22.

h.-

CAT II filter 38.29 This subsystem is not operating.

39.1 2.1.2.2 Refueling Unit 2 39.4 During this mode of station operation, the ventilation system is

~ligned to operate as follows:

39.6 39.7

£*

Fuel building The supply subsystem delivers 34,000 cfm.

Exhaust fans 1-VS-F-7A and B are stopped, isolation

~rip damper AOD-VS-102 is closed, and exhaust stream 11F*

is diverted to the CAT I filter sub-system as deseribed below.

Decontamination building The supply subsystem delivers 9,000 cfm.

39.10 39.13 39.16 39.17 39.18 39.21 39.24 Exhaust stream "D" is discharged at a rate of 39.27 12,300 cfm directly through the ventilation vent by 39.28 fans 1-VS-F-56A and B.

Unit 1 Safe<JUards building The supply subsystem delivers 16,000 cfm.

Exhaust strea~ *sG1* is discharged directly through the yentilation vent by fans 1-VS-F-40A and B with 1,000 cfm drawn from the containment air compressor cubicle and approximately 11,000 cfm from the safeguards room.

40.1 40.4 40.7 40.8 40.9 40.10 Roof fan 1-VS-F-43 exhausts 4,000 spray £Uinp room.

cfm from the 40.12 40 *. 13 Unit 2 Safeguards Building 40.16 The ventilation system operation for this building is 40.19 identical to that of Unit 1.

Auxiliary building The supply subsystem delivers 62,000 cfm.

Exhaust stream "G" is 47,300 directly ~hrough fans 1-VS-F-BA and B.

discharged at a rate of the ventilation vent by 40.22 40.25 40.28 40.29 b-12846.13-6c 10/02/78 083

23.

If all the charging pumps of Unit 2 have been shut down, then one of the* MOD-VS-101 or J.lOD-VS-201 dampers in the £Ubicle of a nonoperating

• charging**

pump is manua11y opened.

This open damper*

• together with the open damper of an operating charging pump of Unit 1. all.ows stream nc*

to be exhausted

~t a rate of 15.500 cfm through the ventil.ation vent by fans 1-VS-F-9A and B,

thus preventing the pressurization of the _!!ux:i1iary building.

40.30 40.30 41.2 41.2/

41.2/

41.2/

Roof fan 1-VS-F-10 exhausts 2,500 cfm if required.

41~6 Reactor containment purge 41.9 The supply subsystem delivers 29,000 cfm to Unit 2 41.10 containment.

E:r.haust stream

• RC2

• is diverted to the CAT I 41

• 10

!_i1ter subsystem as described bel.ow.

41.10

g.

CAT I filter Isolation trip dampers of "F"

and

• RC" streams (AOD-VS-101 and AOD-VS-111) to the CAT. I fil.ter header are opened.

Isolation trip dampers of *sG 1, 11SG2" and.

11c* streams (MOD-VS-100A and B, MOD-VS-200A and B

and ADD-VS-107A and B) to the CAT. I filter header are closed.

A11 eight dampers are electricall.y deenergized to prevent accidental.

change of damper position.

Exhaust fans 1-VS-F-58A and B draw the 11F" and* "RC2"*

streams through both filter *trains 1-VS-FL-3A and B.

The exhaust flow rates of the *r and 11RC2* streams are automatically controlled at 35,500 and 30,000 cfm, respectively.

CAT II filter This system is not in operation.

1-1-2.3 Misc. Maintenance on Unit 2 Foll.owing Refueling

~ing this mode of station operation, the ventilation system is a1igned to operate in the same manner as in Section 2.1.2.1.

JThis means that the dampers which were deenergized in refueling mode described in Section 2.1.2.2

~re electricall.y reenergized during this xoode.

b-12846.13-6c 10/02/78 083 41.14 41.16 41.. 19 41.20 41.21 41.22 41.23 41.2t 41.28 42.2 42.5 42."1 42.7/

24.

2.1.2.4 Misc. Maintenance on Unit 2 Followinq Refueling with Radiation Activity in Exhaust Stream "F*

If radiation activity is detected in the *F* stream following the*

reovement and storage of spent fuel, the ventilation system a1igrunent and operation are identical. to those described in Section 2.1.2.2, ~xcept that power is restored to the open dampers AOD-VS-101 and AOD-VS-111.

£.1.3 Unit 1 Off Line and Unit 2 On Line The operation of the ventilation system during the shutdown, Eurging, and refueling of Unit 1 is identical. to that described for Unit 2 in Section 2.1.2.

2.2 ACCIDENT OPERATION

£. 2. 1 Both Uni ts On Line Followed by LOCA in Unit 1 With the venti1ation system aligned in any one described above in Sections 2.1.1.1 through 2.1.1.s, Unit 1

wou1d

~ealign the ventilation system to follows:

~-

Fuel building of the 100des a

LOCA in operate as 42.12 42.13 42.16 42.17 42.19 42.20 42.23 42.25 42.26 42.30 43.2 43.4*

43.5 43.6 43.9 The supply subsystem may -continue to operate if 43. 11 normal power remains available.

43.12

c.

The exhaust isolation trip damper AOD-VS-102 closes 43.16 automatically and exhaust fans 1-VS-F-7A and B stop automatically.

Decontamination building 43.19 The supply subsystem may continue to operate if 43.21 normal power remains available.

43.22 The exhaust isolation trip damper AOD-VS-104 closes 43.26 automatically and exhaust fans 1-VS-F-56A and B

stop automatically.

Unit 1 safeguards building The supply subsystem is tripped automatically.

Isolation trip dampers AOD-VS-105A and B close automatically ~o establish design flow rate in stream

• sG1," isolation trip damper AOD-VS-106 closes automatically, and exhaust fans 1-VS-F-40A and B

stop automatically to divert *SG1* to the CAT I filter subsystem as described below.

43.29 44.1 44.4 44.5 4*4.-6 44.6/

44.7 b-128-46.13-Gc 10/02/78 083

d.

~-

f.

g.

h.

25.

Roof fan 1-VS-F-43 is tripped autorr.atica1l.y.

Unit 2 safeguards building 44.12 The supply subsystem may continue to operate if 44.14

~orma1 power remains avail.able.

44.15 Exhaust stream *sG2* is discharged directly through the yentilation vent by fans 2-VS-F-40A and B with 1,000 cfm drawn from the £Ontainment air compressor cubicle and approximately 11,000 cfm from the safeguards room.

44.18 44., 19*

44.20 Roof fan 2-VS-F-43 may continue to exhaust 44.22 4,000 cfm from the.§Pray pump room if normal power 44.23 remains available.

Auxiliary building The supply subsystem is tripped automatically.

Exhaust stream *G* isolation trip damper AOD-VS-110 closes automatically, and exhaust fans 1-VS-F-BA and B stop automatically.

Exhaust stream 11c* isolation trip damper AOD-VS-108

£loses automatically, and exhaust fans 1-VS-F-9A and B stop automatically to divert the *c* stream to the CAT I filter subsystem as described below.

Roof fan 1-VS-F-10 stops automatically.

Reactor containment purge

!his subsystem is not in operation.

CAT I filter Isolation trip dampers of *sG1*

and *c* streams (MOD-VS-100A ~d B and AOD-VS-107A and B) open to the filter header. Isolation trip dampers ot the *F," "D,"

and *sG2," streams (AOD-VS-101, AOD-VS-103A and B,

and MOD-VS-200A and B) are closed.

Both exhaust fans 1-VS-F-58A and B start auto~.atically.

,!otal exhaust flow rate through both filter trains would be automatically controlled at 36~000 cfm.

CAT II f il.ter 44.28 45.1 45.2 45.4 45.5 45.. 5/

45.7 45.10 45.12 45.15 45.17 45.18 45.20 45.21 45.. 22 45.23 45.24 Isolation trip dampers AOD-VS-109A and B

close ~nd 45.30 exhaust fan 1-VS-F-59 stops automatical.ly

• b-12846.13-6c 10/02/78 083

26.

2.2.2. Both Units On Line Followed by LOCA in Unit 2 46.3 Ventilation system operation following LOCA in Unit 2 would be.. 46.5 simi1~r to its operation following LOCA in Unit 1, except for the* 46.8 reversed role of the Unit 1 and Unit 2 safeguards.

2.2.3 Unit 1 On Line and Unit 2 Off Line Followed by LOCA in Unit 1 46.12 46.13 With the ventilation system aligned in the Unit 2 cooldown and

£urge mod.es described in Sections 2.1.2.1, 2.1.2.3, and 2.1.2.4, LOCA in Unit 1 would realign the ventilation system to operate as follows:

46.16 46.17 46.19

~-

£*

Fuel building 46.22 The supply subsystem may continue to operate if 46.24 normal power remains available.

46.25 The exhaust isolation trip damper AOD-VS-102 closes 46.29 automatically, and exhaust fans 1-VS-F-iA and B

stop automatically.

Decontamination building 47.2 The supply subsystem may continue to operate if 47.4

!tormal power remains available.

41.5 The exhaust isolation trip damper AOD-VS-104 closes 47.9 auto:matically, and exhaust fans 1-VS-F-56A and B

stop automatically.

Unit 1 safeguards building The supply subsystem is tripped automatically.

Isolation trip dampers AOD-VS-105A and B close

~utomatically to establish design flow rate in stream "SG1" and isolation trip damper AOD-VS-106 closes automatically, s_nd exhaust fans 1-VS-F-40A and B

stop automatically to divert *sG1" to the CAT I filter ~system as described below.

Roof fan 1-VS-F~43 stops automatically.

Unit 2 safeguards building 47.12 47.14 47.17 47.1S 47.19 47.19 47.20 47.22 47.25 The supply subsystem may continue to operate if 47.27 normal power rema*ins available.

47.28 Exhaust stream "SG2" is released directly through 48.1 the ~entilation vent by fans 2-VS-F-40A and B with 48.2 b-12846.13-6c 10/02/78 083

27.

1,000 c£m drawn from the containment air compressor 48.3 Cubicle and

~proximately 11,000 cfm from the 48.4 safeguards room.

Roof fan 2-VS-F-43 may continue to exhaust 48.. 6 4,000 Cfm from the spray pump room if normal power 48.7 remains available.

Auxiliary building The supply subsystem is tripped automatically.

Exhaust stream *G11 isolation trip damper AOD-VS-110

£loses automatically, and exhaust fans 1-VS-F-SA and B stop automatically.

Exhaust stream *c11 isolation trip damper AOD-VS-108

.£loses automatically, and exhaust fans 1-VS-F-9A and B

stop automatically to direct *c-stream to the CAT I filter subsystem as described below.

Roof fan 1-VS-F-10 stops automatically.

Reactor containment purge 48.. 10*

48.12 48.15 48.16 48.18 48.15' 48.19*

48.21 48.24 The supply subsystem fans to Unit 2 containment Ere 48.27 stopped automatically.

The exhaust stream *Rc2* is isolated fr:om the CAT I 48.30 filter subsystem as described below.

49.1 CAT I filter Isolation trip dampers of *sG1* and *c* streams (MOD-VS-100A End B and AOD-VS-107A and B) open to the filter header.

~solation trip dampers of the "F," "D,* *sG2,*

and *RC" streams (AOD-VS-101, AOD-VS-103A and B, MOD-VS-200A and B

and AOD-VS-111)-are closed.

Both exhaust fans 1-VS-F-58A and B

start automatically.

Tota.l exhaust flow rate through both filter trains wou.ld be automatically controlled at 36,000 cfm.

CAT II filter 49.4 49.b 49.7 49.9 49.. 10 49.11 49.12 49.13 49.. 16 Isolation trip dampers AOD-VS-109A and B close and 49.21 exhaust fan 1-VS-F-59 stops automatically.

b-12846.13-Gc 10/02/78 083

28.

2.2.4.unit 1 On Line and Unit 2 Refueling Followed by LOCA in Unit 1 49.25 49.26 With

~he ventil.ation system aligned in the refueling mode des-* 49.29 cribed in Section 2.1.2.2,, a LOCA in Unit 1

would realign the 49.30 ventilation system to operate as follows:

a.

c.

Fuel building The supply subsystem may continue to operate if E_ormal power remains available.

The exhaust isolation trip damper AOD-VS-102 closes automatically,, and exhaust fans 1-VS-F-7A and B

stop automatically.

Decontamination building 50.3 50.5 50.6 so.10 50.13 The supply subsystem may continue to operate if 50.15 E_ormal power remains available.

50.16 The exhaust isolation trip damper AOD-VS-104 closes 50.19 1

automatically, and exhaust fans 1-VS-F-56A and B

stop automatically.

Unit 1 safeguards building The supply subsystem is tripped auto~atically.

Isolation trip dampers AOD-VS-105A and B close

~utomatically to establish design flow rate in

~tream *sG1n and isolation trip damper AOD-VS-106 closes automatically. and exhaust fans 1-VS-F-40A and B

~op auto~atically to divert *sG1* to the CAT I filter subsystem as described below.

Roof fan 1-VS-F-43 stops automatically.

Unit 2 safeguards bui1ding The supply subsystem may continue to operate if E_ormal power remains available.

Exhaust stream *sG2n is discharged directly through the yentilation vent by fans 2-VS-F-40A and B with 1,000 cfm drawn from the containment air compressor cubicle and

~proximately 11,000 cfm from the safeguards room.

Roof fan 2-VS-F-43 may continue to exhaust 4,000 cfm from the spray pllll!p room if normal power remains available.

50.22 50.24 50.27 50.28 50.29 so.29.

50.30 51.2 51.5 51.7 51.8 51.11 51.12 51.13 51.14 51.16 51.17 b-12846.13-6c 10/02/78 083

f.

!3:*

h.

29.

Auxiliary building The supply subsystem is tripped automatica1ly.

Exhaust stream *G* isolation trip dalcper AOD-VS-110

£loses ar.id exhaust fans 1-VS-F-BA and B

stop automatically.

Exhaust stream *c* isolation trip damper AOD-VS-108

£loses automatically, and exhaust fans 1-VS-F-9A and B stop automatically to direct *en stream to the CAT I filter subsystem as described below.

Roof fan 1-VS-F-10 stops automatically.

Reactor containment purge 51.20 51.22 51.25 51.26 s1.2s*

51.29 51.. 29 52.1 52.4 The supply subsystem fans to Unit 2 containment ~re 52.7 stopped automatically.

The exhaust subsystem is isolated from the CAT 1 52.10 filter subsystem as described below.

52.11 CAT I. filter Isolation trip dampers of the *o,* streams (AOD-VS-103) close. Isolation trip dampers of the *F,"

• Rc,n SG1,"

SG2" and *c* streams to the CAT I. filter header _twhich were electrically deenergized as described in Section 2.1.2.2) are electrica1ly reenergized.

This allows dampers MOD-VS-100A and B and AOD-VS-107A and B

to open automatically and dampers

~OD-VS-101, AOD-VS-103A and B, MOD-VS-200A and B, and AOD-VS-111 to close automatically.

~th exhaust fans 1-VS-F-58A and B start automatically. !<>tal exhaust flow rate through both filter trains would be automatically controlled at 36,000 cfm.

CAT II filter 52.14 52.15 52.15 52.15 52.15 52.15 52.15 52.15 52.16

• s2.11 52.18 52.19 52.20 52.22 52.23 52.24 52.28 Isolation trip dampers AOD-VS-109A and B

close and 53.1 exhaust fan 1-VS-F-59 stops automatically.

b-12846.13-6c 10/02/78 083

30.

2.2.5 *Unit 1 On Line & Unit 2 Refueling Follo"'ed by a Refueling Accident Inside Unit 2 Containment or Fuel Building

~ith the ventilation system aligned in the refueling mode de-

.§_cribed in Section 2.1.2.2, a refueling accident inside Cnit 2

,£Ontai.nment or the fuel building would leave the system alignment unchanged, and the ventilation,2YStem would continue to operate as described in Section 2.t.2.2 if normal power !:emains available.

2.2.6 Unit 2 On Line and Unit 1 Off Line and/or Refueling yentilation system operation following a LOCA in Unit 2 or a re-fueling accident in Unit 1 would be similar to its operation des-

£ribed in Sections 2.2.3, 2.2.4, and 2.2.5, except for the reversed role of the Unit 1 and Unit 2.

.J..O SYSTEM FEATURES FOR POTENTIAL EMERGENCIES

!he operation of the ventilation system during the accident ~odes described in Section 2.2 was based on the availability of gonsafety-related equipment, normal electric power, and station compressed air and ~ith no single failure in Quality - category 1 equipment.

!he following sections describe systere features and performances when these failures occur

~imultaneously with the accidents.

l-1 LOSS OF NONSAFETY-RELATED EQUIPMENT

~onsaf ety-related equipment consists

• of the seven ventilation supply subsystems and the CAT II filter subsystem serving the ~G" stream of the auxiliary building.

~l supply subsystem designs include outdoor air intakes without shutoff dampers.

!}:lis feature permits the exhaust ventilation subsystems to draw air into the buildings without ~e benefit of supply subsystem operation.

~he CAT II filter subsystem is automatically tripped following a LOCA ~o prevent it from drawing and exhausting ECCS leakage released inside the auxiliary building.

The loss of operation or the continued operation of the CAT II filter subsystem following a

~efueling accident is immaterial since it does not affect the performance of the CAT I filter subsystem to mitigate the consequences of the accident* in the fuel building or the containment.

Thus, loss of nonsafety-related equipment does not affect system safety functions.

b-12846.13-f>c 10/02/78 083 53.5 53.6 53.7 53.10 53.11 53.13 53.14 53.15-53.18 53.20 53.21 53.23 53.24 53.27 53.29 53.30 54.2 54.3 54.4 51'.S 54.8 54.11 54.12 54.15 54.16 54.17 54.19 54.20 54.. 21 54.22 54.23 54.25

31.

3.2 LOSS OF NORMAL POWER In ad~ition to the nonsafety-related equipment discussed in Section 3.1 above. other equipment powered from the normal bus

'Consist of the filter bypass exhaust fans of the *F." "D*" and

• G* streams (1-VS-F-7A and B1 1-VS-F-56A and. B1 and 1-VS-F-8A and B. respectively)

• The effect of the loss of nonsafety-related equipment due to the loss of normal power on system safety functions was discussed in Section 3.1 above.

The

• F" stream filter bypass exhaust fans are automatically stopped following a LOCA and manually taken out of,Qperation prior to the start of refueling.

The loss or continued operation of the *n* and *G* stream filter bypass exhaust fans following a refueling accident is immaterial since it neither affects the performance of the CAT I filter subsystem nor does it bypass £Ontaminated air around the CAT I filter subsystem.

The D

and G stream filter bypass exhaust fans are automatically tripped followin9 A LOCA.

54.28 54.30 55.1 55.3 55.4 55.,6 55.. 7 55.9 55.10 55.12 55.13 55.14 55.15.

55.15, Thus loss of normal power does not affect system safety 55.16 functions.

l*3 LOSS OF STATION COMPRESSED AIR

!}le use of station compressed air during accident mode operation of the ventilation ~stem is to

~intain the isolation.trip dampers of the *F."

• RC 1 11 and *c* stream to the CAT I filter inlet header (AOD-VS-101 1 AOD-VS-111 1 and AOD-VS-107A and B) in a position opposite to their failure position following a refueling accident.

If station compressed air is lost, then £Ompressed air is supplied to dampers AOD-VS-101, AOD-VS-111* and AOD-VS-107A and B

from a

compressed air accumulator with sufficient capacity ~o

~aintain these isolation trip dampers in the position opposite to their failure modes for two hours.

Two hours is the maximum duration which Regulatory Guide 1.25 postulates for mitigating the £0nsequences of a refueling accident..

55.19 55.21 55.29 55.30 56.1 56.1/

56.1/

56.1/

56.12 56.13

Thus, loss of station compressed

~ir does not affect system 56.13 safety functions.

b-12846.13-6c 10/02/78 083

32.

~-4 SINGLE FAILURE OF EQUIPMENT 56.16 The capability of the exhaust ventilation system to withstand a** 56. 18 singl~ £Omponent failure while performing its safety functions is* 56~19 analyzed in the following table:

b-12846.13-6c 10/02/78 083

Component & QA Cat.

1-VS-F"-581\\ and &

I 1-VS-FL-3A and B I

AOD-VS-101 I

l\\OD-VS-103A and B I

MOD-VS-200A and B I

MOD-VS-100A and B I

AOD-VS-107A and B I

AOD-VS-111 I

b-128116.1J-6d AUXILIARY VENTILATION SYSTEM SINGLE FAILUUE ANALYSIS Safety Function

1.

Exhaust 36,000 cfm following Unit 1 or 2 LOCI\\

2.

Exhauet containment and fuel building to produce inflow of air into both buildings following a refueling accident

1. Filter 36,000 cfm following Unit 1 or 2 LOCI\\

2.* Filter exhaust flow of less than 36,000 cfm from both containment and fuel building following a refueling accident

1.

Close following Unit 1 or Unit 2 LOCA

2.

Remain open following a refueling accident

1.

Close following Unit 1 or 2 LOCA

1. Close following Unit 1 LOCA

2.

Open following Unit 2 LOCA J.

Remain closed following a refueling accident

1.

Open following Unit 1 LOCA

2.

Close following Unit 2 LOCA J. Remain closed following a refueling accident

1.

Open following Unit 1 or 2 LOCA

2.

Remain closed following a refueling acciden.t

1.

Close following Unit 1 or 2 LOCA

2.

Remain open following a refueling accident Component Subject to Failure Yes Yes Yes Yes Yes No Yes Yes Yes No Yes Yes No Yes No Yes No 09/22/78 082 Consequence of Single Failure Exhaust by redundant fan Remarks Exhaust by redundant fan Trip ventilation supply units of bolh lmildinc1s to produce a total ex.haunt flow xate of less than 36,000 cfm from both buildillgs Filter wit.h redundant train f'ilter with redundant train Total exhaust flow rate increases to 71,500 cfm None Close redundant damper Total exhaust flow increases to qe,ooo cfm Open redundant damper None Open redundant damper Total exhaust flow increases to 118,000 cfm None Open redundant damper None Total exhaust flow rate increases to 66,000 cfm None See Notti 2 See Note 1 Dampers in series See Note 2 Dampers in parallel See Note 1 Dampers in parallel See Note 2 See Note 1 Dampers in parallel See Note 1 See Note 2 See Note 1 1

• 111 1.15

1. lb

1. 17 l.10 1.19 1.20 1.21 1 *.lll 1.25

1. 26 1.21 1.20 1.29 1.31 1.32 1.33 1.311 1.36 1.37 1.39 1.110 1.111 1.112 1.113 1.115 1.116 1.117 1.110 1.119 1.51 1.52 1.53

1. !>5 1.56 1.57 1.58

I L-Component & QA Cat.

MOD-VS-101A.e. and c 1.

&MOD-VS-201A.e.and c I

2.

AOD-VS-205A and B I

AOD-VS-105A and B I

AOD-VS-102 I

AOD-VS-10IJ I

AOl>-VS-108 I

AOD-VS-109A and B I

1.

1.

1.

2.

1.

1.

1.

AUXILIARY VENTILATION SYSTEM SINGLE FAILURE ANALYSIS Safety Function Open on operating charging pump following Unit 1 or 2 LOCA Close on nonoperating charging pump following Unit 1 or 2 LOCA Close following Unit 2 LOCA Close following Unit 1 LOCA Close following Unit 1 or 2 LOCA Remain closed following a refueling accident Close following Unit 1 or 2 LOCA Close following Unit 1 or 2 LOCA Close following Unit 1 or 2 LOCA Component Subject to Failure Yes Yes Yes Yes Yes No Yes Yes Yes Consequence of Single Failure Loss of one charging pwnp Total exhaust flow increases to 112.soo cfm Close redundant damper Close redundant damper Stop 1-VS-F-7A and D by tripping CAT II MCC'e which close backdraft dampers None if 1-VS-F-7A and D temain off. See below for the case wlu~re 1-VS-F-7A and B do not remain off_.

Stop 1-VS-F-56A and B by tripping C/\\T II I-ICC's which close backdraf t damper Stop 1-VS-F-9A and B by tripping CAT I NCC 1s which close backdraft dampers Close redundant damper and stop 1-VS-F-59. by tripping CAT I HCC.

AOD-VS-110 I

1.

Close following Unit 1 or 2 LOCA Yes Stop 1-VS-F-OA and B b-128116.13-6d 09/22/78 002 by tripping CAT I MCC 1s which close backdraft dampers.

kemarks See Note 3 See Note 2 Dampers in series Dampers in series Ho adverse effect even if fans with CAT II MCC's do not trip AOD-VS-102 remains closed by redundant sov*s in

• series No adverse effect No adverse effect No adverse effect. Clf 1-VS-F-59 is not tripped by Cl\\T I Mee. unfiltered release of auxil. bldg.

ECCS leakage through closed AOD-VS-109A or B increases control room dose approx.

16~)

No adverse Effect.

Clf 1-VS-F-OA and B are not t.dpped by CAT 1 l*ICC' s

• unfiltered release of auxil. bldg. ECCS leakage through open l\\OD-VS-110 increases control room dose multifo~d)~.

2.2 2.3 2 *

2.5 2.0 2.9 2.12 2.13 2.17

2. 10 2.19 2.20 2.21 2.22 2.23 2.211 2.25 2.20 2.2.9 2.30 2.31 2.311 2.35 2.36 2.37 2 *° 2.II 1 2.112 2.113 2.1111 2.115 2.11 2.117 2.50 2.51 2.52 2.53 2.5*1 2.55 2.56 -

Z.57

Component & QA Cat.

AOD-VS-106 I

l\\OD-VS-206A and 8 I

1-VS-F-7A and B II 1-VS-F-56A and B II 2-VS-F-401\\ and D I

1-VS-F-QOA and B I

AUXILIJ\\RY VENTILl\\TION SYSTEM SINGLE FAILURE ANALYSIS Safety Function

1. Close following Unit 1 LOCA

2. Close following Unit 2 LOCA with HOD-VS-100A or B failed open

1.

Close following Unit 2 LOCI\\

2.

Close following Unit 1 LOCA with HOD-VS-200A or D failed open

1.

Stop following Unit 1 or 2 LOCA

2.

Remain off following a refueling accident

1.

Stop following Unit 1 or 2 LOCA

1. Stop following Unit 2 LOCA

1.

Stop followill<J Unit 1 LOCI\\

09/22/70 Component Subject to Failure Yes Yes Yes Yes Yes Yes Yes Yes Yes 082 Consequence of Single Failure Rema.cks Stop 1-VS-F-40A and B No adverse effect by tripping CAT I MCC 1s which close backdraft dampers Stop 1-VS-F-40A and D No adverse effect by tripping CAT I MCC 1s which close backdraft dampers Stop 2-V-F-QOA and 8 No adveree effect by tripping CAT I "MCC 1a which close backdraf t dampers Stop 2-V-F-40A and D No adverse effect by tripping CAT I MCC 1 s which close backdraf t dampers Unfiltered release of No adverse effect noncontaminated tuel bldg. air leakage through closed l\\OD-VS-102 Unfiltered release of contaminated fuel build-ing leakage through closed AOD-VS-102 in-creasing site boundary dose approx. 3" Unfiltered release of No adverse effect noncontaminated decon-tamination bldg. air leakage through closed l\\OD-VS-104 Unfiltered release of contaminated safeguards bldg. ECCS leakage through closed AOD-VS-206 in-creases control room dose apprCtx

• 5" Unfiltered release of contaminated safeguards bldg. ECCS leakage through closed AOD-VS-106 increases control room dose approx. 5i

~*.

3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.U 3.10 3.11

3. 12 3.13 3.14 3.15 3.16 J.17 3.20 3.21 J.22 3.23 3.24 3.25 3.26 3.27 3.28 3.29 3.32 3.33 3.34 3.35 3.36 3.39 3.*111 3.41 3.42 3.43 3.411 3.47 3.40 3.49 3.50 3.51 3.52

Component & QA Cat.

1-VS-F-9A and D I

1-VS-F-OA and B II 1-VS-F-59 II 1-VS-F-6 II 1-VS-llV-5 II 2-vs-11v-q II 1-vs-11v-q II 1-VS-IJV-11\\ and B II b-12846.13-6d AUXILIARY VENTILATION SYSTEM SINGLE FAILURE ANALYSIS Safety Function

1.

Stop following Unit 1 or 2 LOCA

1.

Stop following Unit 1 or 2 LOCI\\

1.

Stop following Unit 1 or 2 LOCA

1.

Stop following a refueling accident with single failure of 1-VS-F-50A or B

None None None

1.

Stop following Unit 1 or 2 LOCA 09/22/70 Component Subject to Failure Yes Yee Yes No No 002 Consequence of Single Failure Unfiltered release of contaminated auxiliary bldg. ECCS leakage through closed hOD-VS-100 increases control room dose approx. 101 Unfiltered release of contaminated auxiliary bldg. ECCS leakage through closed l\\OD-VS-110 increas-control room dose approx. 15:t.

Unfiltered release of contaminated auxiliary bldg. ECCS leakage through closed AOD-VS-1091\\ and B increases control room dose approx. 121 Remarks None Fan tripped by Cat. I HCC.

(lf not so tripped unfiltered leakRge of refueling accident air increases site boundary dose multifold.)

3.55 3.56 3.57 3.50 3.59 11.1 q...

... 5

• 7

".e 11.9

... 12 11.13 11.111 11.15

,,.16

... 17 ll.20

... 21 11.22 q.23 II.2*1 11.25 4.20

... 29 11.32 11.33 q.36 11.37 None Fans tripped by redundant q.110 CAT I MCC 1s. (It not so 11.111 tripped unfiltered leakage 11.112 of contaminated auxiliary q_q3 bldg. air due to i*ressuriza-II.

tion of bldg. increases q.115 control room dose multifold.)

II

AUXILIARY VENTILATION SYSTEtl SINGLE FAILUHE /lNALYSlS Component & QA Cat.

Safety Function Component Subject to Failure 1-VS-F-qA and B II

1. Stop following a refueling accident with single failure of 1-VS-F-58A or B

No Note 1 These dampers are not subject to sinqle active tailure during None the two-hour period following a refueling accident because they have been electrically deenergized as described in Section 2.1.2.2g.

Note 2 Note 3 Failure of the damper to close constitutes the single failure.

Two filter trains and fans at 36,000 cfm each remain available to treat the increased exhaust flow rate.

Failure of the damper of an operating charging pump to remain open would result in overheating of the pump motor and the possible loss of the pump. lf 'tt1e failed pump belongs to the unit which has had a LOCA, then the accident ls handled with minimum safeguards. If the failed pump belongs to the other unit, then the standby pump is used to shut down the unit.

b-128q6.1J-6d 09/22/78 082 Consequence of Single Failure Hemarks Fans tripped 0 by CAT'1 MCCs.

(If not so tripped, unfiltered leakaqe of re-fueling acc:ident-air in-creases site boundary dose mul tit old. J 11.q9 11.SU 11.51

,,.52 q_53 11.5q q.59 5.1 5.2 5.11 5.5 5.6 5.8 5.9 5.10 s.11

5. 12 5.13

2 3

Lj 5

HV-1 D 6

7 I*

8 A

-.j'*

---

N_Nsr-:ac I a

--JM~loOA

---=--~ov100ci--~)t.1iiv101 r.;\\MOVlOOO 1,

tMl UNlT;;f-1 Cf) I

~

"i~

~-

--'\\r*

r----l"i-,::1,,:::,0v:;;10;:;2-.rna;:-c T'raali 1

• 110v1000 I I

lM) -!-

-~ACTOR ciilrrA11:.:nrrs -

rii) 2-vs-1.10v101 rl-12~~~ /itlS 1.----,w:-1 ){

(ii)

I.

~.

UlllT 2

~) :

c~*;

,..,, 1-vs-J.10*11ooa t-' *H' -+

--" *H

'-'----;'.~

V"

• l

.".' <",1.ac r,.a 1-vs'..11r.v1oa.1

_ 1-vs-1.1oi!_QD~ 1-1*s-1oil!J 2-vs-,101101 Mr"(*-~- --c l J

l-VS-fl-12 ~-~ NNS

~ ' a~ I B.* '

tltlS

-!J.,~- nc I u I,<r FL-14 FILTER TqAINS PRELI Mi NARY 2-VS-H06