ML20236C584
| ML20236C584 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 07/31/1987 |
| From: | SACRAMENTO MUNICIPAL UTILITY DISTRICT |
| To: | |
| Shared Package | |
| ML20236C483 | List: |
| References | |
| NUDOCS 8707300116 | |
| Download: ML20236C584 (42) | |
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3 ,7 RANCHO 'SECO Nud. EAR GENERATING STATION j
-( S UNIT NO. 1 I3 ; t . .-
f. 4y CONTROL ROOM / TECHNICAL SUPPORT CENTER HABITABILITY > l t i REVIS',0N 5
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. TABLE OF CONTENTS
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'1'.0 ' Introduction. 4
~ 2. 0' Sunary ; 15
,- 3~.0.' Control Room /TSC Asbuilt Habitability Syster. 8
,n l 4.0[Ed.luationofControloom/TSCHabitability R 16 Mg . hyaluatio' n?ofL Control Room Habitability 24 Ej ag$ 4 " g% fter' Postulated Toxic Gas Releases -
N, 6.0 39alysir ofnControl s Rocm Operator Radiation 36 g ' Exposure lft m a Design' Basis Accident [ 7- 0 Referenaes' 41 LIST OF TABLES
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14-1 Documents Evaluated for Control Room Habitability 18 4-2 Information Required for, Control' Room Habitability 19
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4-3 Evaluation.'of Compilance with SRP 6.4 22 % '5-1 Companies' Surveyed for Hazardous' Chemicals Used or 28 Transported within 5 Miles of the Plant' i 5-2 Onsite Toxic: Chemicals- 29
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'5-3 Evalvption of Hazardous Gas Concentrations in the 30' 1 Control Room
, 5-4 Control Room Isolation Characteristics 31 6 Control Room Operator Radiation Exposure from Airborne 38
% % Radioactive Materials 6-2 Control Room Operator. Radiation Exposure from All. Sources 39 s> [
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Page 2-1 Plan of Control Room / Technical-Support Center 7 3, 3-1: System Flow Diagram 15 5-1 Major Transportation Routes near' Rancho Seco 32
.5-2 Major' Transportation Routes near the Plant 33 5-3 ' Plot Plan Showing Location of. Hazardous Chemicals 34 5-4 General Arrangement Plan at Grade Showing Location of 35 Hazardous Chemicals 6-1 Relationship'of Reactor-Building Leakage Points to the 40 Contrc Room Emergency Air Intakes.
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1.0 INTRODUCTION
-This report,-in previous < revisions,-evaluated the Rancho.Seco-Nuclear
.: Generating -Station _ Unit'l- Control- Room (CR) and Tecnnical Support 1 Center (TSC) for conformance to: current Control-Room /TSC habitability requirements. Aieds of nonconformance were identified and appropriate
. modifications were recommended. The' modifications, with improvements arising from IE Information Notice No. 86-76 (Ref. 7.16) have been completed. :This revision to the report is based on-the modified-Control Room and Technical Support Center to demonstrate compliance i with current habitability requirements for these spaces.
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SUMMARY
The Control Room emergency zone was extended to include the newly redesigned TSC area. The new Control Room /TSC habitability system is described in Section 3. The entire space within the extended Control Room Envelope (CRE) has been evaluated for conformance to current Control Room /TSC habitability requirements in Section 4. The design incorporates all the items noted in the NRC's SER on NUREG 0737, item III.D 3.4 (Ref. 7.18) as modified by the NRC letter (Ref. 7.19 and 7.20). 2.1 CONTROL ROOM /TSC EMERGENCY HVAC A. The original (Train B) Control Room Essential HVAC air. handling, refrigeration, and filtration system was abandoned in olace and replaced with two new redundant Quality Class I, Seismic Category 1 units with cooling to serve both the Control Room and TSC. B. Existing Class 1 (Train B) ductwork inside the Control Room and computer room has been extended and augmented to serve as common ductwork for distribution of both Train A and Train B emergency cooling air. C. Two new 100% capacity filtration units which meet the guidance of Standard Review Plan 6.5.1, (Ref. 7.8) and Regulatory Guide 1.52 (Ref. 7.10) were installed to provide filtered recirculation and filtered outside makeup air for pressurization to meet single failure criteria. D. Automatic CRE isolation is provided on detection of a chlorine release. Automatic detection for other chemicals, (e.g. ammonia) is not required, based on the analysis in Section 5. E. The system has been tested to verify that the Control Room /TSC can be pressurized at least to 1/8 inch water gauge relative to all surrounding air spaces while supplying makeup air at no more than the design rate. The ability to attain and maintain the 1/8 inch water gauge will be periodically tested as a technical specification surveillance standard test (18 month intervals, or each refueling whichever occurs first). F. Distribution ductwork for the TSC area is utilized by both essential and normal HVAC systems and is designed to Quality Class 3, and Seismic Category 1 supported. The TSC area can be isolated from the Control Room essential system by smoke or fire dampers in case of smoke or fire inside the TSC. i 1 G. Train related bubble tight isolation dampers have been installed i in the existing supply and return normal ducts at the pressure l boundary for the CRE. Fire dampers are installed in the existing normal and essential supply and return ducts between the Control l Room and TSC and at the Control Room /TSC CRE pressure boundary. 5
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'2.2:' ADDITIONAL FEATURES m,2 T -
JA.,lA critical: document reference file'has been provide'd--inside the-
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, B. Self-contained.breathin'g apparatus.for at least five. men have . l
- been provided inside the Control-Room.and a six. hour bottled air-
'h 4 sup' ply with unlimited offsite replenishment,'along with .
appropriate use procedures.
'C. Administrative controls over Control P.com and:TSC doors have been installed.
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D. A potassium iodide' drug supplyLis provided near the Control Room. ,
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-2.3 ' ACCIDENTAL RELEASE OF T0XIC CHEMICALS-
]:i Potential sources'of toxic chemicals within five miles of the plant !
L-have been evaluated. One offsite chemical and 12 onsite chemicals ; were considered for their potential impact on the Control Room. [ . 7 ; Section 5 contains the results'of the toxic gas analysis. ! 1 L 2 AL RADIATION EXPOSURE q Radiation exposures t'o'the Control Room operators, both direct and .i airborne contributors,.have been evaluated in Section 6; Thel resultant i exposures-were'found-to be acceptable. !
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s -, c 3.0 CONTROL ROOM /TSC'ASBUILT HABITABILITY SYSTEM 3.1 DESIGN BASIS A. The habitability system envelopes the rooms of the Control Room /TSC as shown in Figure 2-1 and listed below:
- 1. Control Room (339)-
- 2. Computer Room (338)-
- 3. Shift Supervisor's office (340) a
- 4. Conference Room (341) '
- 5. Kitchen (342)
-6. -Toilet (343)
- 7. Corridor (344)
- 8. 'TSC (334)
- 9. ' Conference Room (335)
- 10. Conference Room (336)
- 11. Corridor (333)
B._ The CR/TSC Essential HVAC system is designed to maintain conditions within the' envelope suitable for prolonged occupancy throughout the duration of any design basis accident. C. The Control Room /TSC is designed for sustained occupancy of at least five persons'in the Control Room and 25 persons in the TSC. 1
.D. Provide sanitary-facilities for susta'ined Control Room occupancy.
E. The radiation exposure of Control Room and TSC personnel does not 1 exceed the limits stipulated in General Design Criterion 19 ;! (Ref. 7.9). i F. The CR/TSC HVAC system is capable of automatic and manual transfer from the normal system to the Essential HVAC system in either the radiological (recirculation with outside makeup air for pressurization) mode or the toxic (recirculation without. outside makeup) mode. G. The Control Room /TSC pressure boundary i:1 pressurized with . outside air to a minii,mm.of 1/8 inch water gauge relative to all ) surrounding air spaces and ventilation systems when the Essential i HVAC system is operating in the radiological mode. ' H. A single active failure of a component of the CR/TSC Essential HVAC system, assuming a loss of offsite power, can not impair the capability of the system to comply with design basis A, B, C, E, F and G, listed above. l I. The CR/TSC Essential HVAC system is designed to remain functional f during and after a safe shutdown earthquake. 1 J. All ductwork and supports not required by the Essential HVAC ; system have been evaluated for impact on safety Class 1 systems ; and found to be acceptable. 8 i (f
f K.; Respiratory, eye, and skin protection are provided for-emergency 1 use within-areas of-the Control Room /TSC envelope. L. ' Protective > equipment (self-contained breathing apparatus and anti-contamination clothing) are available and maintained'for five-(5) stafffpersonnel. 3.2 SYSTEM DESCRIPTION A. The CR/TSC HVAC system consists.of an existing normal dual duct HVAC system for.the Control Room, a'new common air distribution system for'the'TSC; area:and two-new 100 percent capacity
' Essential HVAC' units, one powered-from each safety train, A and B.
B., ' Normal HVAC
- 1. The Control Room continues to be served by existing dual-duct HVAC unit AH-A-1 during normal operation of the plant.
Existing normal duct work, where it passes through the walls' at the Control Room /TSC extended pressure boundary has been L removed and replaced with Seismic Class 1 ducts. 'Two bubble-tight isolation dampers actuated from separate trairs are
, installed wherever ducts pass through.the CR/TSC pressure boundary.
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2.- The TSC room,-its two conference rooms ar.d corridor are supplied from existing air handling unit AH-A-2 which had previously supplied conditioned air to'this portion of the building. A new air distribution system has_been installed to serve these spaces; the new duct system.is connected to the cold duct of air handling unit AH-A-2 outside the TSC complex..LTrain related isolation dampers are installed at the Control Room /TSC pressure boundary. The dampers are of bubble tight design. All ductwork where it passes through the Control Room /TSC i pressure boundary and up to and including both isolation dampers is Quality Class 1, Seismic Class 1. Ductwork inside the TSC complex is Quality Class 3, Seismic Class 1 supported. Temperature control for the TSC c6mplex is in/ reheat utilizing an electric duct heater. 9
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- 1. The CR/TSC HVAC system is configured asLshown in Fig. 3-1. R
'The essential-filtrationftrains are' designed:in-accordance with Standard Review Plan.6.5.1,;"ESF Atmosphere Cleanup-Systems'? (Ref. 7.8) .and Regulatory Guide 1.52, (Ref. 7.10).
Two HVAC trains'(A & B) are provided, each sized for'100-percent capacity. Each train consists 1of: an essential air ' -; handling' unit'and condensing unit, an' essential:airL q
, --filtration unit and_a physically separate outside air.
intake._ The systemLutilizes an air distribution system inside the Control' Room area which-is common to' essential. 'i
~ Trains A'and B and a separateEair distribution system within j
'the TSC complex which -is. common to essential Trains' A andlB
'and to -the Normal' HVAC system,-'with appropriate' isolation. ]j dampers.
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- 2. .The Essential HVAC trains'are Quality Class 1, Engineered-
' Safety Features systems.
- 3. The Essential Filtration Units consist of a booster.. fan-with-variable' inlet vanes, two 2-inch deep carbon adsorber banks, HEPA filters upstream and downstream of-the carbon adsorber an electric air heating coil'and a moisture eliminator / pre-
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filter.
- a. .The essential air filtration system is designed to:the-requirements of Regulatory Guide.1' 52, '(Ref. -7.10).
Components are designed, constructed'and_. tested in accordance with-ERDA:76-21,' ANSI N509 and ANSI N510 (Ref. 7.2, 7.13, and ' 7.14) -as indicated .in Regulatory ' l Guide 1.52. l
- b. Electric Air Heater In order to maximize carbon adsorber_ efficiency, an electric heating coil is' provided to lower the relative humidity of the outside air / return air mixture to 70 percent or less.
- c. HEPA Filters HEPA filters banks are provided upstream and downstream of carbon adsorber banks. The HEPA filters'are designed and tested in accordance with Regulatory Guide
.1.52 and ANSI N.510 (Ref. 7.10 and 7.13).
- d. Carbon Adsorbers The carbon adsorbers for the Essential Air Filtration Units are tray type as described in ERDA 76-21 (Ref.
7.2); two banks of 2 inch deep type II trays for an equivalent bed depth of 4 inches, designed and tested in accordance with Regulatory Guide 1.52. l 10 m LL
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- 4. - Each Essential Air l Handling: Unit consists of a fan, direct
' expansion (Refrigerant-22) cooling coil and medium Lefficiency~ filter.
5.- The Essential HVAC system is'; started and CRE is isolated automatica}lywheneverthetemperatureinthe. Computer. Room exceeds 80 F.' Temperature in the Computer Room is'the most' i critical of all.the' spaces served by.the CR/TSC~ essential H',AC system. D. Duct Systems
- 1. Safety-related:ductwork'is designed per ANSI"N509 ar,d ERDA 76-21. The appilcable seismic response spectra were utilized in the design-of the Seismic Class 1 ductwork.
Welding:for safety related ducts conforms ~to AWS D 1.1, D 9.1 and.D 19'0 and ASME B&PV Code, Section IX.
- 2. Separate train related ducts from each Essential Air Handling Unit connect to Control Room'and TSC' distribution systems. The train related ducts are Quality Class 1, Seismic Class.1.
- 3. Separation is provided between components of the two '
essential trains to ensure that a failure of a component of one train cannot cause-the failure of the other train.
- 4. 'The Essential HVAC' system has been designed-to remain functional during and after a safe. shutdown earthquake (SSE).
- 5. In the TSC area where the normal and essential HVAC systems utilize common ducting, and wherever normal ducting passes- j through the CR/TSC pressure boundary, automatic isolation is '
provided-upon receipt of-either a radiological or toxic gas signal. , l 3.3 CONTROL ROOM ACCESS D0 ORS l To minimize in-leakage, the Control Room access doors have airtight seals, and self-closing devices to shut the doors automatically. Entrance and-exit doors are provided with separate card readers and automatic closers. 3.4 TSC ACCESS D0 ORS
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To minimize leakage that would result from uncontrolled ingress and egress of 25 TSC personnel, the TSC personnel doors are provided with card readers and with self-closing devices to shut the doors automatically. The TSC doors are instrumented in the Control Room. , l 1 11 : [
3.5 T0XIC' GAS SENSORS Class 1E chlorine gas sensors located at the ttnk' farm and their
. associated control system provide-early detection- and isolation of the CR from its normal HVAC system following a chlorine release and ,
starting of essential HVAC system.in the 100% recirculation mode. J 3.6 RADIOLOGICAL SENSORS j Class 1E Radiological sensors and their associated control systems are 1
-installed for activation of the CR/TSC' Essential HVAC system in the l radiological mode. l The bubble-tight isolation dampers in the outside air intakes of each j train upstream of the Essential Filtration Units (Fig. 3-1) are opened f only following a radiological accident (by radiological sensors located at the outside air intake of the normal HVAC system) or f ailure of the normal Control Room HVAC system (by temperature sensors L located in the computer room). When the Essential HVAC system is operating under these conditions, outside air to pressurize the Control Room /TSC will be filtered. Therefore, additional radiological sensors for installation in the essential system outside air intakes
- l are not required.
3.7 CONTROL ROOM AIR LEAKAGE i The analysis of infiltration and exfiltration has been performed using the methods and assumptions given in Regulatory. Guides 1.78 and 1.95, Standard Review Plan 6.4, and the ASHRAE Handbook of Fundamentals (Ref. 7.3). The Control Room /TSC has been tested to verify the ability of the system to maintain a minimum of 1/8 inch water gauge i relative to all surrounding air spaces and ventilation systems while pressurizing with filtered outside air at a maximum makedp rate of ' 1760 cfm. An unfi'tered infiltration rate has been calculated for ; the analysis, j The outside air isoletion dampers are assumed open for the analysi.s of k the radiological mode of operation and u sumed'closeel when the Control Room /TSC is analyzed for operation in the toxic gas (isolation) mode. Because the TSC is directly coupled to the Control Room for the 1 analysis, the TSC has been designed to the same criteria as the l Control Room. ' 3.8 INSIDF DESIGN CONDITIONS A. Emeroency Operation The Control Room /TSC Essential HVAC system is degighed to maintain the Control Room and TSC at or below 80 F maximum. l Humidity is not directly controlled; however, the system design ) inherently limits the humidity to a maximum of 60 percent. The ' entire Control Room /TSC is controlled as a single zone with separate temperature switches for each train located in the Control Room. l l l 12 1
Normal ' Operation B .- The' original' normal HVAC systems fo'r Control Room and TSC are designed to maintain a maximum temperature of 78 F during normal operation.- No modifications to the heating and cooling capabilities'of the existing' air handling units were required, except..for balancing the systems. 3.9 - HVAC: SYSTEM OPERATING SEQUJ!CE - f A. Normal Operatior,
- 1. During normal operation, conditioned air for HVAC for the Control Room complex is supplied by' air handling unit AH-A-1 through the cold and hot ducts of a " dual duct" system .to special zone mixing boxe , which blend cold and hot or warm ;
air as required by 7 individual. zone thermostats. Room air ' is returned to the air handling unit through a' return air i duct and mixed with outside air to make up for exfiltration and exhaust. Three exhaust fans exhaust air from the toilet, kitchen and conference room.
- 2. Cooling. air for the TSC complex is supplied from the cold air duct of air handling unit AH-A-2. An electric dect heater is installed in the TSC cold air supply duct to reheat the supply air as required by a thermostat located in
-the west conference room.
B. Emergency Operation
- 1. During an emergency condition the Essential HVAC system ;
supplies air for environmental control to all of the spaces l of the Control' Room-and TSC areas. The space enveloped by i the Control Room /TSC pressure boundary constitutes a single zone which is served by one of two redundant essential HVAC trains. Each train includes an air handling unit, a j refrigeration condensing unit, a filtration unit, control ~ dampers and duct work which supplies the common air l distribution duct systems within the' Control Room /TSC envelope. Each train is controlled from separate temperature sensing elements located on the south wall of the Control Room.
- 2. Upon receipt of an emergency signal (Radiological, Toxic Gas, or high temperature) both essential HVAC trains may start, one of which can be secured by operator action.
- 3. During an emergency condition train related isolation dampers in the normal duct system at each penetration of the Control Room /TSC pressure boundary, are closed, including train related isolation dampers in each of the ducts to the three exhaust fans. j 13 l
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. During any' emergency condition normal air handling unit-AH-A-1:does not operate. The unitsis stopped by'a flow switch in the' normal:returncair duct which responds'to the reduction in,airsflow'resulting from the closing of the:
~ : isolation ' dampers.
- 5. During' a Radiological Event after steady airtflow th'roughi the filtratn unit has been established, the train related-o outside air intake dampers are opened, and filtered.outside.-
air is introduced to pressurize the Control-Room /TSC to 1/8
. inch water gauge minimum.
p , !6. : Following4a' Toxic Gas Event'the Essential HVAC is operated -
.in a recirculation mode with-thettrain related bubble-tight. .
outside : air: isolation dampers inf the closed position and the filtration unit operating.
- 7. .When:a~ Toxic' Gas. signal'is received-with:the essential HVAC system already operating in the- radiological mode, the outside air. isolation dampers are. closed and the system .is -
operated with 100 percent recirculation. "
- 8. :When the essential HVAC is started due to high temperature
-in the Control Room, the system is' operated in the radiological. mode.
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. 4.0 EVALUATXON OF CONTROL ROOM /TSC HABITABILITY $
( L 4.1 CONTROL ROOM HABITABILITY
=The. Control-Room design was evaluated for conformance with current habitabil.ity. requirements. Table 4-1 lists the primary. documents i reviewed. Secondary documents referenced by these documents were
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evaluated as necessary. A. NUREG 0737. Item III.D.3.4 At,tachment 1 I See Table 4-2 for evaluation.. B. Standard Review Plan 2.2.1-2.2.2 Potential offsite and onsite chemical hazards are identified in Sections 5.1 and 5.2 respectively.of this report, as required by- 1
-Standard Review Plan' 2.2.1-2.2.2.
C. Standard Review plan 2.2.3 Evaluation of potential accidents identified in sections 5.1 and i 5.2 are evaluated in.Section 5.3 in accordance with SRP 2.2.3. ' The nature cnd magnitude of the hazards does not require a statistical evaluation. D. Standard Review plan 6.4
- See Table 4-3.
E. Reculatory Guide 1.52 A review of the Conforming Technical Specification-(Reference : 7.17, section 9.2.3) indicates compliance with the intent of ! Regulatory Guide 1.52. G. Regulatory Guides 1.78 and 1.95 i As indicated in Table 4-3, section II.S.b, the Essential HVAC for the CR/TSC has been designed to protect the CR/TSC from accidental releases of toxic gas following the guidelines of R.G. 1.78 and R.G. 1.95. 4.2 TECHNICAL SUPPORT CENTER-HABITABILITY Habitability requirements for the TSC-are specified in NUREG 0696, :' Section 2.6. The primary requirement is that the TSC shall have the same radiological habitability as the Control Room under accident conditions. The TSC HVAC system is required to function in a manner comparable to the Control Room HVAC system. A. The four rooms constituting the' Technical Support Center are within the Control Room pressure boundary. 16 l __d
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- .' ' B.- The'TSC HVAC duct system is connoctedLto the Control Room essential-HVAC system, and' operates in the same manner and meets ,
the:same performance criteria as the Control ^ Room essential HVAC ! system. C. The TSC HVAC ductwork although not required to be, is seismic -; Category 1 supported. D. The TSC Essential HVAC system is combined with'the' Control Room essential HVAC system outside of the TSC and is redundant. This exceeds the NUREG 0696 requirements. ,
' E. The HEPA filters and carbon adsorbers required by NUREG 0696 are also required 1by SRP 6.4 and have been provided as a part of the combined Control Room /TSC essential HVAC system. :
F. -For detailed compliance of both the Control Room and.TSC. Essential HVAC systems with SRP 6.4, see preceding section 4.1. ; G. A supply of potassium iodide tablets is located near the Control Room for use by TSC and Control Room personnel. H. A radiation monitor is installed in the TSC room. i I P
?
j i L , 17
y
' :?
i Table =4-1 1 DOCUMENTS EVALUATED FOR CONTROL ROOM HABITABILITY Document Title NUREG 0737, I'nformation required for Control Room Item III.D.3.4 Habitability Evaluatio'n. ' Reference 7.6. Attachment.1. SRP 2.2.1-2.2.2 Identification.of' Potential Hazards in Site Vicinity. Reference 7.21. SRP. 2.2.3. Evaluation of Potential Accidents.
, Reference 7.22.
.SRP 6.4 Habitability Systems. Reference 7.7.
Regulatory Guide 1.78 Assumptions for Evaluating the Habitability of a Nuclear Power Plant Control Room During a Postulated Hazardous Chemical' Release. Reference 7.11'. Regulatory Guide 7.95- Protection of Nuclear Power Plant Control Room ) Operators against an: Accidental' Chlorine Release. 1
. Reference 7.12. 'l 1
l j ; [ 1 l i 1 [ 18 L
-3 g '
t Pj? l r i; 4
' Table 4-2:
'INFORMATIONREQblREDFOR. CONTROL ~ ROOM HABITABILITY EVALUATION
- L(Ref.-NUREG.0737, Item III.D.3.4,' Attachment 1)
Item. 1 Subject .Information 1.. Control ~ Room Mode of Operation. a. ' Pressurization and. filtered? Recirculation for- Radiological: Accident.
- b. Isolation and filtered-Recircu--
lation for toxic gas release. I2. Control. Room' Characteristics 104800 Ft3 gross volume'-
- a. Air Volume - Control .
~ Room, emergency zone. ,
- b. Control' Room emergency See.section 3.1lA and-figure.2-1.
' zone.
- c. CR ventilation system See figure 3-1.
schematic.
- Normal Flow OSA Intake Flow 810 cfm nominal Recirculation Flow 13915 cfm nominal Supply Air' Flow' 14725 cfm nominal Exhaust Flow 710 cfm' nominal
. a Emergency Flow OSA Intake Flow.
=1760 cfm. maximum 'l' Re.irculation c ilow 14940 cfm minimum Supply Air" Flow 16700 cfm nominal
- d. Infiltration Leakage Rate. Pressurized 100 cfm Isolated <110 cfm
- e. Filter Efficiency. HEPA 99%
Carbon Adsorber. Elemental Iodine 99% Organic Iodine' 99%
- f. Closest distance See Figs. 5-4 and 6-1. I between containment and CR. air intake.
i g, g , , 19
.a- c
$'- a
; .i
- Table 4-2'(Cont.)
. Item subject Information i
- g. . Layout of' Control Room,. See Figs. 5-3 and 5-4. ,
. air intakes,. containment {
building,'and: chemical storage facilities. l i
.h. . Control: Room shielding. USAR Section 11.2.2. !
i Automatic isolation USAR' Table 9A-1. Closing time capability. 'less=than'10 sec. (see Fig'.-3-1). j.. Chlorine detectors. Remote, see sections 5.3,.5.4. !
.;, j
- k. Self contained breathing H Eight air packs available.in apparatus. Control, Room.
- 1. Bottled air supply. 36. additional .1 hour - rated. air.
bottles in TSC' corridor:for total: : of 44 bottles. : I' Emergency food and Not required per NRC letter
- m. .)
. potable water. supply. .
(Reference 7.19 and 7.20). . j
'l n.- Control' Room personnel At'least five. '
capacity.-(Normal and Emergency)
- o. Potassium iodide supply. ~
In Emergency Locker near the Control' Room.
- 3. 'Onsite storage of chlorine and ,
other hazardous' chemicals. }
'a. Total amount and size of See Table 5-2.
. container, j l
- b. Closest distance from See Figures 5-3 and 5-4. l
. Control Room air intake. !
- 4. Offsite manufacturing, storage I or transportation facilities of 1 hazardous chemicals. '
a '. Identify facilities None. within a five mile radius,
- b. Distance from Control Room. .N/A .
1
. , 20
_ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ - ~
7- ' - 4
' ' e' t j . Table 4-2.(Cont.) q
-\
Item ' Subject Information
- c. Quantity.of' hazardous 'See Table'5-1 chemicals.in'one container. and section 5.1.2.
- d. ' Frequency of. hazardous 'See section'5.1..
. chemical transportation i
. traffic.
- 5. Technical Specifications
- a. . Chlorine. detection systems. See Table 5-4.
- b. Control Room emergency Tech Spec Section 4.10.
filtration system. k
'i ;
I i 21
Table 4-3 EVALUATION OF COMPLIANCE -i WITH SRP 6.4 -l 4 4 Section Subject Evaluation II.1 Control Room Emergency Zone (CRE-zone) 1 II.1.a I & C'for-safe shutdown, critical document reference file. .'Within zone -- complies. Within zone complies. ! II.1.b Computer room. Within zone - complies. II.1.c Shift Supervisor's office. Within zone - complies. I II.1.d Operator wash room and kitchen. Within zone - complies. .; II.2 Ventilation System Criteria- l II.2.a. Isolation dampers. Bubble tight, documented in USAR (Section 9.7.3.1.A)
- Complies.
II.2.b Single failure. Complies. 111.3 pressurization Systems II.3.a Systems >0.5. volume change /hr Complies.
- verify makeup is + 10% of design.
II.3.b Systems with >0.5 vc. Not. applicable. II.3.c Systems with >0.25 vc. Not applicable, j II.4 Emergency Standby Atmosphere Regulatory Guide 1.52 l
' Filtration System guidelines used in design '
see Section 4.1.F. j 11.5 Relative Location of Source and Control Room l II.5.a Radiation Sources. Complies.
- II.5.b Toxic gases. Complies. Following the )
^ ~
guidelines of Regulatory j Guides 1.78 and 1.95 the CR/TSC has been designed j for an accidental toxic j gas release. r i 22 i 1
l
'1 i
Table 4-3 (Cont.l l 3 Section Subject l Evaluation 1 1 II.6 Radiation Hazards Complies. (See Section 3 6.0). II.7 Toxic-Gas Hazards Complies. (See Section. 5.0). Clarifications: II.3.a Proposed amendment No.'161 would have the makeup air checked every 18 months or each refueling, whichever occurs first, to verify'that the makeup air flow does.not exceed'a maximum value, of design flow plus 10% while maintaining at least 1/8" water gauge. Minimum value not specified.
. II.5.a Reference to Figure 6-1 indicates that some potential release points of radioactive material are'less than 100
-feet laterally and 50 feet vertically from the Control Room ventilation inlets.
However, analyses have been performed which show the ' CR/TSC meets habitability limits. Thus'the intent of the SRP has been meet. i l l 2 j l l i i 1 23
ra' .. f '
- , 5.0 EVALUATION OF CONTROL ROOM HABITABILITY AFTER p0STULATED T0XIC
. GAS RELEASES
-The evaluation of postulated toxic = gas accidents proceeded as follows:
In Section 5'.1, potential offsite. toxic gas accidents are identified, o In;Section 5.2, potential onsite toxic gas accidents are identified. In Section 5.3, potential ~ toxic gas accidents are evaluated for 4 potential Control Room concentrations. Finally, Section 5.'4 discusses 1 the design requirements to mitigate the. consequences of accidents.that can lead to excessive Control Room concentrations. 5.1 IDENTIFICATION OF 0FFSITE CHEMICALS Toxicichemicals within a 5-mile v.icinity of the plant were evaluated for potential gas concentrations in the Control Room. Within the vicinity (Fig. 5-1) there are only two transportation routes: a j Southern Pacific Railroad line and California State Highway 104'(Twin i Cities Road). There are no military facilities or large chemical i concerns. A. Rails The Southern Pacific Railroad (SPRR) line by the plant connects r Stockton-Sacramento-lines (more than 6 miles west of the plant) to a terminus in Ione (about 10 miles east of the plant). < B. Roads l
.The cities of Sacramento, Stockton and Ione form a road 'i transportation triangle shown to scale-in' figure 5.1-2. Tnere 1 are:no other major transportation routes within the triangle. i Because ther~e is no industry within the five mile. vicinity of the plant, companies in the vicinity of Ione were evaluated for j
_applicationLof their toxic chemicals. The companies that were investigated for transportation of toxic chemicals are listed in Table 5-2. The' table also indicates the results of the' investigation. At a minimum, each company was ! asked (i) Dc they transport toxic chemicals near the plant, (if yes, then they were questioned as,to quantity, type, and frequency) and (ii) Could they identify any other company that might use toxic chemicals and might' transport near the plant. (Each of the investigated companies seems to take a substantial i interest in the safe operation of their nuclear neighbor). John Taylor Fertilizer indicated that they transport 1000 gallon tanks of 82% ammonia at irregular intervals to the various agricultural concerns around the plant. As a rule, the company indicated that the ammonia would be used within hours of delivery. To conservatively calculate the potential consequences of an ammonia road accident, the ammonia was assumed to be pure (100%) ammonia, and the accident was assumed at the closest offsite location service by Taylor (D 3in gure 5-1). 24
e
,1 ; . The 'other companies indicated that they preferentially use H highways Is and 88 rather than highway 104.
5.2-' IDENTIFICATION OF ONSITE CHEMICALS J 1 - -
. i Onsite toxic chemicals were identified by a' site survey, review of the-FSAR, review of plant general-arrangement and plot plan drawings,
] f review of the plant Equipment List and review of the Plant System 1 . Descriptions. Twelve toxic chemicals were identified. Their location, distance from the Control Room and quantity are identified ;
in Table-5-2 and' figures 5.2-1 and 5.2-2. 1 Caustic' soda (sodium hydroxide), the last chemical in Table 5-2, was j
'eliminatedfromfurther, analysis.-Causticsodadoesngtcontaingases !
and its vapor pressure at the elevated temperature 739 C is 1-mm Hg. Consequently at near-ambient temperatures the vapor evolution is j
-negligible.
-l i
5.3 T0XIC GAS CONCENTRATIONS IN THE CONTROL ROOM AFTER POSTULATED ACCIDENTS i The verified Bechtel computer program T0XGAS was used to evaluate toxic gas concentrations in the Control Room. The model is consistent with NUREG-0570 Regulatory Guides 1.78 and 1.95. Accidents were postulated to occur with the "short term" meteorology used to answer ! AEC question 9.17'in the FSAR. Higher wind speeds were evaluated when the higher wind speed increased the accident: severity. The' Control Room toxic gas concentrations for the one chemical in ' Table 5 (Ref. Section 5.1.B) and the first 11 chemicals of Table 5-2 i were evaluated based on the guidance of Regulatory Guide 1.78 in Table i 5-3. Only two chemicals require protective action: ammonic and ; chlorins Procedures for postulated accidents with toxic chemicals i are presented in Section 5.7. t 5.4 DESIGN REQUIREMENTS TO MITIGATE CONSEQUENCES OF POSTULATED T0XIC GAS ACCIDENTS Of the two postulated toxic chemical accidents that lead to excessive Control Room concentrations, the chlorine accident is the more restrictive. Control Room design alternatives for the chlorine accident.are evaluated in Section 5.5. The present design is presented and evaluated in Section 5.5.C. ' The design presented in i Section 5.5.C is then evaluated for the postulated ammonia accident in Section 5.6. Procedures common to all toxic chemical accidents are presented in Section 5.7. 25 1
4
- v ,
' ' ~
^ 15;5E POSTULATED-RUPTURE OF A ONE TON CHLORINE TANK'IN THE' CHLORINE'BulLDING
. Design alternatives <for' postulated: toxic. gas accide'nts that lead to excessive Control l Room concentrationslare< presented in Standar'd Review-Plan Section 6.4 subsection'III.5.b and. Regulatory Guide l'.78 and l'.95.-;Threel limiting designs were evaluated. :In Section 5.5.A',-
designs that do not require' operators to don' personal air breathing :l apparatus are evaluated. In.Section 5.5.8, designs without? remote chlorine _ detectors'are evaluated. :In Section 5.5.C, the preferred ; design is evaluated.- r
-A. 'Desians Not Reauiring Air Breathing Apparat _uis .
Rapid detection'and Control Room isolation with minimal e infiltration can limit toxic gas concentrations.to acceptable-
. levels. -Th'e maximum permissible exposure limit of' chlorine allowed'by?the General: Industry Safety Orders:of-the State?of California is'1' ppm. The. threshold of noticeable odor is 3.5 ppm and a concentration up;to 4 ppm:can be. ingested for one hour without serious effects. To' limit the maximum chlorine.
concentration to 3.5 ppm,.the' Control' Room:-infiltration'must be below 5 cfm.(0.002 Lair. changes per hour). Consequently, this design alternative was not recommended.
.B.
{ D_etection at the Outside Air Intake ; Rapid chlorine detection'atlthe Control Room normalHVAC (outside) air intake with Control -Room isolation and the operator use of air-breathing-apparatus is an acceptable design if the-operators have~at least two minutes to'put on the apparatus..
, :With detection at the air intake and'immediate Control Room isolation, the maximum tolerable Control Room infiltration is 30 H cfm -(0.02-air exchanges per hour). Consequently this design _ was not recommended.
C. Preferred Design: Detection at the tank farm Regulatory Guide 1.78 (Reference 7.11) lists 15 ppm of. chlorine as the maximum. concentration that can be tolerated for two
- minutes without. physical incapacitation of an average human. By chlorine' accident detection at the tank farm, the operators can
-take-the: precautionary, action of donning personal air breathing apparatus at least'two minutes .before Control Room concentrations exceedt15 ppm. Limiting Control Room isolation parameters for the recommended design are presented in Table 5-4.
The. chlorine detector location or setpoint may be altered within limits to avoid unnecessary " Spurious" activations. Postulated accidents that can lead to excessive Control Room concentrations require source (and intermediate) concentrations in excess'of 15 ppm. The recommended setpoint provides indi'.ect protection for 3 all plant personnel. Neither does the detector have to be in the chlorine building. The primary purpose of remote detection is to provide an early alarm for operators to don breathing apparatus. i A ~ ' '
a
- s ,
a
} '
o ,
* ' j' Win'd spe6d,-detector location;(distance from accident source-and' r
g distance ~from'the Control Room intake),.and dete' ctor' response-time;are.the primary' variables"in evaluating toxic gas
' ']
j Z',- concentrations in the Control Room'after'a chlorine acc' dent. { 3 1 Redundant chlorineL. detectors-(Train:A'and Train B):have been. .) Llocated in thestank' farm at.least 165 feet from the. Control Room-air' intakes.. A11owing'20 seconds for monitor response,' adequate
, -response time forLoperation to donLbreathing. apparatus.is?
L provided takingsinto consideration the~ wide cange.of possible; wind speeds at the site.:. This placement alsoLprovides: indirect-
- protection for all plant personnel.
] I 5.6 POSTULATED RUPTURELOF.APMONIA. CONTAINERS: .
. Automatic detection and Control Room' isolation is not required for:an' .!
ammonia accident because the Control Room concentrations of ammonia l will not increase'.tol100: ppm.inLless'than the two minutesrafter the odor is detectable by the operators. 'The potential ammonia' accident: j]- isisuch that many minutes are' available to evaluate' the accident before air' breathing' apparatus is required. The odor threshold. for ammoniaLis 47 ppm. The recommended procedure is immediatt j (within 2 minutes) operator use of' air l breathing apparatus (see section 5.7). 5.7L PROCEDURES F09. T0XIC. CHEMICAL ACCIDENTS
' Emergency actions to minimize the consequences of a toxic gas release are embodied in Casualty-ProcedureJC.46,'" Hazardous. Substances !
Spills / Releases." Chl'orine releases are. addressed specifically, while !
. generic steps are,given-for other hazardous subs'tance releases. 1 l
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I COMPAN8SSURVE'YEbFORHAN,ARDOUS-CHEMICALS'USEDOR, iA['
+
qi TRMSPORTED WITHIN 5 MIMS:0F THE PLANT-r , y
. Company / Location
~
Hazardous Chemicals OT American Lignite- Products.(209) 274-24i)7 None
- South offBuena Vista y y 49
~
iBendix (209) 223-1660- '
- None
-(Includes: Amador- Central; Railroad)
.Ione'
'0 wens-Illir,ois (209) 274-2471. None
' Highway 124 ~
.Interpace (209,) 274-2453 None Highway 124 Zenith Clay.(209) 274-2453 Highway 3124' None
-Preston Schooli(209) 274-2421.- None-State of California, Dept. ofLYouth Authority
*Simpiot?(209) 457-2387 .
None
- Lodi
- John Taylor Fertilizer (916) 776-2113 82% ammonia-in Sacramento 1000 gal tanks
'* Largest chemical ~ distributors in the area.
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l ONSITET0X1h. CHEMICALS i I)3 V b
- h. .t Wii '
Distpnce to Y C' N A, J
. Chemical Quantity UkormalIntade Location /Cchente
\
. Ammonia (28%). 12000 gal :.500 ft V Tank'y V-7AS, west.of g 'y,' auxiliary' 'do ll er j Carbon Dioxide 7.5 tons 200 ft ; Tank V-99'8, CO -
2 il Ii,uilding
' Chlorine '
1 ton tanks Sq0 ft Tanks V-745A thru C, l Chlorine Building j Diesel' Oil 200,000 gal J900.ft Tank T-897, south of W. ) Cooling Tower Hydrazine (35%) 55 gal drum 300 ft Warshise "B" I
~
Hydrogen 3000 scf M rI 550 ft .,nks V-920, North of 4/ tanks . Auxiliary Boiler Hydrogen Peroxide 55. gal drum 800 ft Warehouse "B" Freon 113 55 gal drum 800 ft"3 Warehouse "B" Nitrogen 30000 ccf per 550 ft Tanks V-925, Nor $ of 5 tanks Auxiliary Loiler. Propane 115 gal 450 ft Tank V-935, North of ' Auxi'liary Boiler Sulfuric Acid 16000 gal. Son ft TankT-743,SouthofE.
. Cooling Tower Caustic Soda .11000 gal 500 ft Tank T-741, South of W.
Cooling Tower P9
y _ _ _ . . . _
.sy o.
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, : Table 5-3'
\;if s
- b. : EVALUATION OF HAZARDOUS GAS CONCENTRATIONS IN THE CONTROL ROOM
- y (After P6stulated Accidents and Without Protective Action) o
- .TLV, PPM- Objectives of Item Vessel Contents- - By Volume -SRP'6.4' Met? 1 ;28% quas' Ammonia .254 , 55 5,:100 6 ***No***7 2" : Carbon ^ Dioxide 50004 ,/20000 5 Yes 2 4 5 6
'3 Chlorine 1 , 4 , 15 '***No***3 4 I
4 1 4 ' Diesel Oil 1 Yes . 4 5- 35% Hydrazine- 0.1 , 1.0 5 y,3 2 j
.I 4'
'Yes1 '
y 6: Hydrogen , '143000 [HydrogenPeroxide 4 i-7 .1 - Yes 4 8 Freon 113 1000 ' Yu l ) Nitrogen 4' l l . ,;,; 9 1143000 . Yes I 4 1
,7 10 LPropane. .143000 ~ Yes 1
- w. 1 4 1
'11 Sulfuric Acid 0.25 Yes -
4 5 6 W: y 12: Ammonia (Offsite) 25 , 55 , 100 .. ***No***7
' 1. - ' Threshold limit value (TLV) for an acute 8 hour exposure is not exceeded.
- 2. Threshold limit value for an acute 8 hour exposure is temporarily eexceeded,'but TLV for a 1 hour exposure is not exceeded.
- 3. ' Threshold limit value for 2 minute exposure is exceeded.
4.- Threshold limit value for continuous, 8 hour exposure.
- 5. : Threshold limit value for a 1 hour exposure.
'6. Threshold limit value for a 2 minute exposure
- 7. The buildup from detection'to incapa' citation is greater than 2 minutes,.but the note 3 value is exceeded.
o 30-1
). l 4 l I l Table 5-4 CONTROL-ROOM ISOLATION CHARACTERISTICS Postulated Accident Chlorine , Detector location Tank Farm (Separate Train "A" and Train "B"). (Ref. Section 5.5.C) Detector Setpoint. 1 ppm Maximum isolation delay time (includes 20 sec detector response time and Control Room isolation time). 1 Maximum Control. Room infiltration 110 cfm (inc1uding in-leakage from ducts, (0.06 air air handling units, filtration units, changes per. hour) ! dampers and doors). Time for operators to don air 2 min k breathing apparatus. Objectives of SRP 6.4 met Yes
- 1. Set by chlorine accident b.
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e 5 MILES 16 4 IONE ' 104 RANCHO SECO 1 LOOi o i e STOCKTON MAJOR TRANSPORTATION ROUTES NEAR THE PLANT. COMPANIES NEAR IONE PREFERENTIALLY USE HWYS 16 8 88 OVER HWY 104. FIGURE 5 2 __ _ _ _ _ . _ _ _ _ _ _ _ - - - - - - ~ "' ' ' '
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4 ' 6.0'1 ANALYSIS OF CONTROL ROOM OPERATOR RADIATION EXp0SURE FROM A DESIGN BASIS p ACCIDENT 1 6 1!:DIRECTn.ADIATION The direct radiation exposure to Control Room operator originates from six sources: (A) Direct gamma. dose from the reactor. building attenuated by the containment wall and Control Room _ shielding, (B) 1 Direct gamma dose'from the plume ~resulting from containment leakage, 0 (C)-Internal and external doses from airborne radioactive materials - which may reach the Control Room with the emergency HVAC pressurization air,.(D) Direct exposure from: systems required to-
' process primary reactor coolant-after an. accident, (E) Direct gamma dose through containment' penetrations, and-(F) Direct' gamma dose from activity deposited in the Control Room HVAC and Auxiliary Building HVAC filters attenuated by Control' Room Shielding. l
' Source A and B were presented in FSAR Section 14.3.9:7 and total less than,0.11 rem.
Source C is evaluated in Section'6.2. Area dose rates 3
' for Source D were. evaluated in' Reference 7.15. The time integrated !
dose to~the Control Room operators using Source D is presented.below. The evaluation of direct exposur.e.from systems required to process-primary coolant after an. accident,. presented.in Reference 7.15, resulted in post accident radiation zone maps and curves of normalized . dose rate versus time. The radiation zone map at the turbine deck
' (el. 40'-0") shows the Control Room console-area and entryway is in
. g' radiation zone A (less than 15 mr/hr), and the adjoining support-instrumentation area is in zone B (15 to.100'mr/hr). The Control Room '
kitchen, bathroom,-c~onference room and supervisor's office are also in < zone A.. 1 A realistic estimate of the maximum operator 30 day integrated dose i
.would-include consideration of operator occupancy factors in zones A and~B. In this evaluation, the conservative assumption was used that the operator stays in zone B and that the dose rate is the upper limit l within the zone of 100 mr/hr. The integrated operator-dose using the ,
conservative source C-(of Reference 7.15) is than 1.4 rem. An operator spending half of his Control Room time at the console,. , conference room, or supervisors office would receive a maximum dose of 0;81 rem from source D. The maximum allowable whole body gamma dose is 5 rem. i 6.2. AIRBORNE RADI0 ACTIVE MATERIALS In the interregnum between the FSAR amendment 10 calculations of the Control Room operator dose from airborne radioactive materials and the-present' evaluation the regulatory assumptions on Control Room
.(unfiltered) infiltration have'become better defined. The effect of an assumed 100 cfm infiltration (Ref. Table 4-2) and the full capacity for Control. Room pressurization is evaluated in Section 6.2.B for the current' design. The results of the calculation and the relevant FSAR calculation are summarized in Table 6-1.
36
A. Comparison to the FSAR Thyroid and whole body doses were presented in the FSAR response. to AEC Question 9.17. For comparison, the doses are included as i the first line of Table 6-1. B. New Control Room Design i The new Control Room design differs from the previous design by
^
having a larger (maximum) design pressurization flow (1760 cfm maximum versus 400 cfm), the addition of at least 1760 cfm of filtered recirculation and allowable infiltration of 100 cfm. The combined effect of the larger filtered inflow, larger infiltration, and added recirculation is an increased thyroid dose and small changes in the wholebody dose (2nd line of Table 6-1). C. Total Radiation Exposure The total dose to Control Room personnel from a design basis accident is the sum of sources A-F. This dose 2.4 rem whole body and 14.9 rem thyroid (Table 6-2) remains below the maximum permissible dose as given in 10CFR50 Appendix A, GDC-19 (Ref. 7.9). This calculated dose includes the effects of:
- 1. increased flow during initial stabilization;
- 2. sustained outside air flow of 1760 cfm (1600 + 10%);
- 3. both trains actuated together, second train secured after 5 minutes.
(Note: With both Trains operating for the duration of the event 10CFR50, Appendix A, GDC19 limits would not be exceeded). I 37
Table 6-1 CONTROL ROOM OPERATOR RADIATION EXPOSURE FROM AIRBORNE RADIOACTIVE MATERIALS Thyroid Wholebody Dose Rate (rem)' (rem) 6.2.A FSAR' Response (Amendment 20) '.. 79 '0.'184 l 6.2.B Current design 14.9 0.41 t a 4 6 I.i , l 1 1 l 1 4 1 38- , .
[.:'_ : 4. . , , '\
> . i
.3 c .. 'i
.9-
,J Table 6-2 .
3
, ; CALCULATED CONTROL' ROOM OPERATOR' RADIATION l:
- i. EXPOSURE FROM ALL SOURCES
. JThyroid. Wholebody i
Source Dose (rem)' Dose'(rem) .g
- A ---
<0.10
~
B ---. <0.01 1
.C 14.9 0.41 L D- ---
1.4' r <- E' --- --- F- ---
.43 TOTAL- 14.9 2.4 Maximum Permissib1'e Dose 4 - 30 5
)
%-10CFR50, App. A, G.D.C.19 l
' and SRP.6.4, Section II.6. I 1
..p , .m - - , - 39 -
j
r. I: *
. ?
. j
-l
' FUEL TRANSFER TUBES S '
PLANT VENT DISCHARGE [ PERSONNEL Q, EL. 5'-0" ESCAPE . LOCK EL.146'-U* 2
/
MAIN FEEDWATER
. ( EL.16'-4" L
EQUIPMENT i HATCH ( EL.9'-6" REACTOR FUEL STORAGE B G eP BUILDING OUT ET ( EL. 32'-0" TURBINE BUILDING NEL
$R q EL.45'-0" a
ROOF EL.20'O" - l k.
'I l AUXILtARY BUILDING
- PURGE INLET 1.- .
q, EL.32'-0" MAIN STEAM LINESj ROOF EL. 60'-0" l
\ -
.i-( EL 4'- 0" bCONTROL ROOM NORMAL AIR lNTAKE (REF.)
PRESSURE EL. 20'- 0" EQUALIZATION LINE EL. (-) l l'-6" CONTROL ROOM EMERGENCY VENTILATION SYSTEM OUTSIDE -j AIR INTAKES PENE N A3EA *
~ ,
EL.(-)20 - AND EL 20'-0" i RELATIONSHIP OF REACTOR BUILDING LEAKAGE POINTS TO THE CONTROL SCALE NONE ROOM EMERGENCY AIR INTAKES F10URE 6 l l j AD 1
s
7.0 REFERENCES
7.1 D.G. Eisenhut, NRC, Letter to All Operating Reactor Licensees, May 7, 1980. 7.2 ERDA 76-21, " Nuclear Air Cleaning Handbook Design, Construction and Testing of High Efficiency Air Cleaning Systems for Nuclear Application", Oak Ridge National Laboratory, C. A. Burchstead, J. E. Kahn, and A. B. Fuller, March 31, 1976. 7.3 ASHRAE, " Handbook of Furidamentals",1977 edition, i i 7.4 NUREG-0570, " Toxic Vapor Concentrations in the Control Room Following ' a Postulated Accidental Release", NRG J. Wing,1979. 7.5 NUREG-0696, Rev. 1, Functional Criteria for Emergency Response Facilities. 7.6 NUREG-0737, Item III.D.3.4, Control Room Habitability Requirements. 7.7 USNRC Standard Review Plan, Section 6.4, Rev. 2, Control Room Habitability System. 7.8 USNRC Standard Review Plan, Section 6.5.1, Rev. 2, ESF Atmospheric Cleanup t Systems. 7.9 Criterion 19 - Control Room - of Appendix A " General Design Criteria for Nuclear Power Plants" to 10CFR Part 50. 7.10 Regulatory Guide 1.52, Rev. 2, " Design, Testing, and Maintenance Criteria for Post Accident Engineered-Safety-Feature Atmosphere Cleanup System Air Filtration and Adsorbtion Units of Light-Water-Cooled Nuclear Power Plants", March 1978. 7.11 Regulatory Guide 1.78, Rev. 1, Assumptions for Evaluating the Habitability of a Nuclear Power Plant Control Room during a Postulated Hazardous Chemical Release, June 1974. 7.12 Regulatory Guide 1.95, Rev. 1, Protection of Nuclear Power Plant Control Room Operators against an Accidental Chlorine Release, January 1977. 7.13 ANSI N509-1980, Nuclear Power Plant Air Cleaning Units and Components. 7.14 ANSI N510-1980, Testing of Nuclear Air Cleaning Systems. l 7.15 Letter from J. J. Matimore to R. W. Reid, USNRC, April 11, 1980. 7.16 IE Information Notice No. 86-76: Problems Noted In Control Room Emergency Ventilation Systems, August 28, 1986. 7.17 Specification M13.16 Essential Air Filtration Units, August 20, 1982. 7.18 NRC SER Input for Rancho Seco Unit 1 from the Accident Evaluation l Branch on NUREG-0737 Item No. III.D.3.4, " Control Room Habitability", l April 9, 1982. 1 41 l L .
- ;e ' '
- -f-7.19' John F.:Stolz, NRC,: Letter to R. J.-Rodriguez, SMUD,. April.30,-1985.
7.20' Letter.from R..J. Rodriguez to John F.'Stolz, NRC, July 5, 1984. 7.21: USNRC Standard Review Plan, Section 2.2.1 - 2.2.2 Identification of Potential Hazards in Site Vicinity, Rev. 2.
.: - 7.22 USNRC Standard Review Plant, Section 2.2.3, Evaluation of Potential
-Accidents, Rev. 2.
-v
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