ML20214T965
| ML20214T965 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 11/30/1977 |
| From: | NORTHEAST NUCLEAR ENERGY CO. |
| To: | |
| Shared Package | |
| ML20214T944 | List: |
| References | |
| TAC-7355, NUDOCS 8706100499 | |
| Download: ML20214T965 (24) | |
Text
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l MILLSTONE NUCLEAR POWER STATION
- UNIT NO. 1 i
DOCKET 50-245 3 STEAM DILUTION OFF GAS REQOMBINER/
. AUGMENTED OFF GAS SYSTEM 9
November 1977 8706100499 780213 POR ADOCK 05000245 P0Q
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1.0 Summary Page 1 3 l
2.0 System Description Page 2 I j
3.0 System Operation Page 6 4.0 Safety Analysis Page 7 l 4
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1.0 Summary _
An augmented off-gas treatment system is being installed at i Millstone Unit 1 to further reduce off-site doses. This system consists of a steam dilution recombiner system, which removes hydrogen and thereby reduces the gas volume, and a xenon-kryptoa treatment system to increase the holdup of xenon and krypton to 50 and 1.3 days respectively. .
The original off-gas system for Millstone Unit 1 was designed to route off-gas from the steam jet air ejectors of the main steam condensers, through a delay pipe where radioactive isotopes j underwent decay. After a minimum of 30 minutes, the gases exited the delay pipe and were exhausted through HEPA filters to the station stack. The system reduced off-site doses below the limits of 10 CFR 20 in effect at the time of issuance of the Millstone Unit 1 Provisional Operating License.
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1 2.0 System Description -
In a BWR Plant, steafn jet air ejectors are used to remove air ,
inleakage, water vapor, radiolytic. hydrogen and oxygen along with l l
trace quantities of fission product and activation gases from the main condenser for processing by the off-gas system. The gas flow i into the first stage ejectors will be controlled by adjustable i butterfly valves which will limit the flow to a. maximum of 50 SCFM. l This will ' allow operation of the off-gas system during plant i startup and during transients. The existing second stage ejectors 1 will be modified to bypass the aftercondensers and discharge the j motive steam and gas to the process pipe. The process stream, containing a gas / steam mixture raised to the necessary inlet pressure, with the hydrogen concentration diluted below 4.0 volume j percent, is transported to the recombiner system. l The gas / steam mixture is preheated in a shell-and-tube type heat exchanger to the necessary recombiner inlet temperature. The hydrogen and oxygen react stoichiometrically in a catalytic recombiner to form steam. The motive steam, no longer needed for hydrogen dilution, and the reaction product steam are cooled and condensed in the off-gas condenser. The gas remaining consists of a residual quantity of hydrogen, water vapor, the inleakage air, and traces of non-condensible radioactive isotopes. A jet compressor will raise the pressure of the gas to that required for transport j to and processing by the xenon-krypton treatment system. The gas then goes to the plant stack for discharge.
2.1 Recombiner System The Recombiner System consists of two full capacity. redundant trains each containing a preheater, a catalytic recombiner, an off-gas condenser, a jet compressor, an after-cooler con-denser, an instrumentation and control system and the required interconnecting valves and piping. The two trains are designed i to be operated separately. A flow diagram of the off-gas :
system is shown in Figure 1. !
The preheaters are standard shell and tube heat exchangers utilizing plant auxiliary steam which has been throttled to 270 psia and 408 F to preheat the incoming gas / steam mixture from 250 F to 320 F. The temperature rise furnished by the (
preheater provides the required superheat for initiation of t the exothermic reaction in the.recombiner. The superheated, ,
diluted mixture enters the recombiner where the free hydrogen and oxygen react in the presence of the catalyst to form water.
The recombiners are full flow units employing a precious metal-coated metal base grid catalyst bed. Each bed has approximately twice the quantity of catalyst required to completely react the free hydrogen and oxygen. Due to the exothermic reaction the temperature will be increased by ,
approximately 125 F per percent hydrogen in the inlet stream, l Thermocouples are provided at three points in each bed and at the inlet and outlet of each recombiner. These temperatures
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__._.a x are for monitoring recombiner performance. Strip heaters are-provided to maintain the standby recombiner at 320 F and for preheating the unit during startup.
4 The gas exits the recombiner at approximately 730 F and enters the off-gas condenser where it is cooled to 130 F. The con-densed water is drained to a subcooler; cooled to 110 F and returned to the main condenser. Cooling water to the off-gas condensers and subcoolers is supplied from main cycle condensate entering at a maximum of 105 F.
A jet compressor which provides~the motive force for the recombiner system, increases the pressure of the gas leaving the off-gas condenser from approximately 12 psia to 19 psia.
The steam supply for the compressor is prov1ded from the same source that furnishes steam to the preheater.
The gas exits the jet compressor appr6ximately 340 F- and enters q the after-cooler condenser where it is cooled to 130 F. The l condensed water is drained to the hot gas stream entering the off-gas condenser. The off-gas leaving the after-cooler con-denser is transported to the xenon-krypton treatment system which was described in Millstone Nuclear Power Station Unit 1, Radwaste Modification, US AEC Docket 50-245, . submitted in -
July, 1973.
The minimum flow of 25 SCFM required by the xenon-krypton treatment system is provided by makeup air from the plant station air system and injected automatically into the gas stream at the preheater. A flow bypass loop is provided from the discharge of the after-cooler condenser to the suction of the jet compressor, so the jet will operate with constant suction conditions. The discharge pressure is determined by the non-condensible flow rate through the xenon-krypton system. The jet compressor is capable of discharging 50 SCFM at about 22.7 psia.
2.2 Xenon-Krypton System The xenon-krypton treatment system is a low temperature
(-20F) charcoal absorption system, housed.in a separate building about 1400 feet from the recombiner building and about 400 feet from the stack.
The system consists of two sections: pretreatment and' charcoal adsorption. After catalytic recombination and transport to the xenon-krypton system, the off-gas enters the pretreatment equipment. This consists of two full capacity systems, each containing a cooler-condenser, a moisture separator, cyclic dryer, glycol cooler units, interconnecting piping and instru-mentation and control. The pretreatment glycol cooler unit contains two (2) full capacity pumps, two (2) 500l gallon-i storage tanks and two (2) full capacity refrigeration machines.
The pretreatment system is designed to cool the off-gas to
-20F and dry the stream to a dewpoint of -90F, f
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l After drying and pre-cooling, the off-gas flows through a gas cooler to two (2) charcoal beds in series maintained' at
-20F. Each bed contains 11,000 pounds of activated charcoal.
Two beds operating in series Will provide a delay of.1.3 days for krypton isotopes and 50 days for xenon isotopes at the normal flow of 25 SCFM. After decay in the charcoal beds, ,
the off-gas flows.to the existing high efficiency particulate filters prior to release to the environs from the 375 foot stack. .
The process and physical details of the xenon-krypton treatment ~j
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system were presented in the Radwas_te Modification submittal dated July 1973, Docket 50-245.
2.3 Re_ combiner System _ General Arrangement, Structures, Plant Tie-Ins The recombiner system is located at grade elevation in a building which has been specifically designed to house this system. The recombiner building is located adjacent to the present office building and turbine building.
Each of the redundant recombiner systems is housed in a separate shielded compartment.to enable maintenance to be.
performed on the standby unit. Instrumentation racks are located in a: third separate compartment which is accessible during operation of either system.
Valving has been provided to diver ~t the main condenser steam jet air ejector outlet flow to either the delay pipe (original mode of operation) or to the inlet of the preheaters for treatment through the new system. These valves are operated from a panel in the main control room.
The recombiner system utilizes main plant condensate, auxiliary steam, service air, instrument air and station A-C electric power. The main plant condensate can be isolated from the recombiner system by redundant safety class valves controlled by the plant safety systems. Partial or total loss of these support services may result in shutdown of the recombiner syste:n, however the system is designed to preclude off-site consequences and damage to the recombiner or xenon-krypton systems from such losses. The loss of a support system will be either directly alarmed in the main control room, or indirectly alarmed as a result of creating an upset condition l in the gas stream. !
2.4 Codes-and Standards The equipment and piping will be designed to meet the following
' codes and standards: ,
4 Quality Group Branch Technical Position ETSB No. _11-1 Rev. 1 dated l 11/24/75
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. . l ANSI B 16.34 Welded Valves ANSI B 16.5 Flanged Valves ANSI B 31.1 Valves and Piping - 1973 ,
issue including summer ]
1976 addenda (
ASME.Section VIII, Div. 1 Off-Gas Preh' cater Shell Catalytic Recombiner Off-Gas Condenser Shell After-Cooler Condenser Shell TEMA Standards Off-Gas Preheater Tubes I Off-Gas Condenser Tubes !
After-Cooler Condenser Tubes 2.5 Instrumentation and Control Instrumentation for the control and monitoring of the recombiner system is listed in Table 1.
The off-gas flow in each of the redundant systems is instru-mented for temperature, pressure and flow. In addition, the cooling condensate flow is instrumented for flow and differ-ential pressure across the off-gas condenser waterboxes.
The off-gas inlet valve to each cyctem is so interlocked that if there is no condensate flow through the off-gas condenser as reflected by low waterbox differential pressure, the valve cannot be opened. Furthermore, high gas temperature at the recombiner discharge will close this valve. A low gas flow, measured at the off-gas condenser discharge, will open the makeup air valve admitting air to the preheater to maintain the flow requirements of the xenon-krypton treatment system.
The majority of the recombiner system is maintained at a subatmospheric pressure by controlling the off-gas condenser outlet pressure with the jet compressor bypass control valve.
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L 3.0 System Operation 1 The augmented of f-gas system will be operated from the main control room. The system will operate using one of the recombiner subsystems, one of the Xenon-Krypton pretreatment subsystems, one of the Xenon-Krypton charcoal subsystems, and one of the stack filters, before discharge through the plant stack. The recombiner and Xenon-Krypton -
pretreatment subsystems may be selected remotely from the main control room.
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The expected performance of the augmented off-gas system is presented i in Table 2. i i
The system is designed to process the air ejector effluent during normal plant startup and operation. Additionally, the delay pipe off gas system, provided with the original plant, is available for !
l service in the event. difficulties with the augmented system are experienced.
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. O il 4.0 Safety Analysis An analysis has been performed to determine the noble gas off-gas processing system release rate that would result in a calculated-offsite whole body dose of-5 rem assuming a Safe Shutdown Earthquake (SSE) with subsequent pressure boundary failure of all non-seismic Category I off-gas processing.and storage equipment. This. analysis used the same approach taken in Radwaste_ Modification _, Supplement ,
2_, as submitted on Docket No. 50-245 in August,1975. ,
a The offsite doses as a result of a postulated seismic event have U been evaluated assuming a complete loss of all offsite power and j a single additional active component failure. A description of l
the accident sequence and the major source term assumptions are "
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discussed below.
The Xe-Kr Building which houses the off-gas processing system ,
charcoal beds is a seismic Category I structure. In addition I the charcoal beds and associated process stream piping and valving located in the Xe-Kr Building between valve V2-350 (located upstream j of the charcoal beds) and the scismic Category I plant stack are also designed to seismic Cctegory I criteria.
For the purposes of this analysis it has been assumed that as a result of the SSE all non-seismic off-gas processing system equip-ment fails and results in the complete release of the radionuclide inventory contained in this equipment. The non-seismic componento that are assumed to fail are:
- 1) the 12" process pipe upstream of the recombiner system,
- 2) the recombiner section of the off-gas processing system ]
located adjacent to the Turbine Building and, l
- 3) the transport pipe from the recombiner building. 1 All releases from these: components are assumedLto be instantaneous and at. ground IcVel at the location of the Turbine Building..
In addition to these releases it has been conservatively assumed i that the Steam Jet Air Ejector (SJAE) continues to operate and !
release gases for one hour subsequent to the SSE. ,
Termination of the process flow stream through the charcoal beds 1 will occur when, upon loss of offsite, power, air operated valves. l located in each train of the off-gas system automatically fail closed upon a loss of electric power. Once these valves (FCV-401, l FCV-402, FCV-403, FCV-404, FCV-409 and FCV-410) have closed, there will be no mechanism other than the heating up (with subsequent , ;
pressurization) of the beds that could~potentially result'in any '
significant release of gases adsorbed on the charcoal beds.
Since a small portion of instrument piping tapping off of the ;
main process stream is not seismicly qualified, isolation of the. !
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.. 1 m charcoal beds will be accomplished by the closing of manually operating valves located upstream and downstream of the charcoal 1 beds. These valves are V2-350 through V2-358 and IV-11,.12 and 14.
It should be noted that the manually operated valves necessary to isolate the beds are all located within a single easily accessible, l well shielded, area within the Xe-Kr Building. Each two inch valve can be rapidly closed by a quarter turn _of-the valve handle.
.Nevertheless, it is conservatively assumed that operator action to close all of the valves necessary to isolate the charcoal beds-takes one.. hour.
As indicated above, isolation upstream of the charcoal beds will be accomplished by the closing of manually operated valves. Since two manually operated valves are provided in series upstream of the charcoal beds, this portion of the ' system will be abic to =
withstand a single active component failure, i.e., a failure of a i valve to close, without the loss of its isolation capabilities.
Normally, total isolation of the charcoal beds would be accomplished by the closing of manually operated valves located downstream in each charcoal bed train. However, for the purposes of this evaluation, it has been assumed that one of these manually operated valves is
" stuck" in the open position and cannot be closed by the operator.
As a result of this open valve, all gases that are eventually released from the charcoal beds will be routed to the plant stack.
However, credit for release via the stack is not assumed until one hour subsequent to the SSE since an instrumentation line tap, located downstream of the beds and the manual isolation valves, could fail during a SSE. The termination of any gaseous releases from this instrument tap will be accomplished'by the closing of the instrument tap root valve IV-14. After this valve and the other manually operated valves located upstream and downstream of the beds are closed, all releases from the beds will be via the plant stack. The q releases from the charcoal beds prior to isolation of these valves I is assumed to be ground level at the location Xc-Kr Building. ]
l In order the calculate the offsite doses for the postualted accident sequence described above, the release of noble gases from the charcoal beds has been conservatively analyzed assuming:
- 1) a single active component failure in a manually operated seismic .
Category I valve downstream of one charcoal bed train and 2) that j the non-seismic Category I glycol cooler units fail as a result of the SSE.
1 The results of this analysis demonstrate that the releases from the -
charcoal beds will be less than 3% of the total initial bed inventory during the first two hours due to the extremely slow heating up of the beds. The releases for a thirty day accident duration have been determined to be slightly higher, ,
The results are as follows: j i
1
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D Release Fractions (%)
Time Following SSE Bed Temperature ( F) Kr Xe j 1 Hr. -19 2.2 41 2 Hr. -18 2.2 <1 30 Days ambient 6% < 1% ,
The releases were calculated based upon the following:
- 1) The charcoal beds are insulated with 4" of polyurethane i insulation. This foam is contained in a welded steel shell surrounding each bed.
- 2) The decay heat generation rate as a result of the charcoal bed radio-nuclide inventory is 1000 Btu /hr (based upon the proposed source term of 2,800,000 uCi/sec at 30 min. decay).
- 3) The maximum transfer of ambient heat into the charcoal beds is less than 2100 Btu /hr assuming a temperature differential of 100 F between the beds and the ambient environment.
- 4) The releasec from the beds were calculated using the methodology described in a paper entitled " Effects of Rupture in a Fission Gas Holdup Bed" by D. Underhill presented at the 12th AEC Air Cleaning conference. i
- 5) Following initial bed depressurization, charcoal bed heatup is the only release mechanism since the process system flow has been automatically terminated.
The results of the analysis show that the two hour dose at the .
Exclusion Area is limiting. This is because (1) the incremental releases for a 30 day accident duration are only slightly greater ;
than those for the 2 hr. time period; (2) the 30 day doses have been evaluated at a Low Population Zone (LPZ) distance of approxi-mately 3900 meters as opposed to a distance of approximately 600 ?
meters for the 2 hr. Exclusing Distance calculations; and (3) after the first hour of t ehaccident all release from the charcoal beds are via the plant stack. Thus the discussion that follows will be limited only to the 2 hr. dose results.
The 1971 BWR mix normalized to 100,000 microcuries/sec. after 30 minutes decay is shown in Tabic 3-A. Activation gases and radio-active halogens found in the gas stream are shown in Table 3-B.
As indicated above, even assuming a single active component failure of one manually operated valve downstream of the charcoal beds, the releases from the beds within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> will be less than 3% of the initial bed inventories. A comparison of the dose contribution from the SJAE, recombiner, and transport pipe shows that the charcoal releases will not significantly increase the 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> dose, as shown ;
in Table 4.
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i Based on the above discussion and the assumptions given in Table 5,' the two hour whole . body dose based upon a noble gas in process activity rate of 350,000 uCi/see at 30 minutes decay is calculated to be 0.61- rem as :
shown in Table 4. The activity release rates of'significant' radionuclides. .; '
from the SJAE and the significant radionuclide inventories in the off-gas processing system used in this analysis are listed in Table 7 and 8, re-spectively. Normalizing the two-hour dose to the 5 rem criterion, an allowable off-gas system in process activity rate of 2.8' x 106 uC1/sec at .
30 minutes decay is calculated as shown in Table 6.
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l TABLE 1-j INSTRUMENTATION t
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Control _ .
Recorded Alarmed Function . Indicated .3 j
- Parameter . -
X
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Recombiner System Inlet Pressure' X Pr heater Inlet Temperature -High/ Low X
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Prlheater Outlet Temperature X High/ Low l
RehombinerBedTemperature- X High X
Recombiner Outlet Temperature High
- Off-Gas Condenser Outlet Temperature X X Off-Gas Condenser Outict-Pressure High/ Low X X Off-Gas Condenser Hotwell Level High X I Jet Compressor Discharge Temperature .
X High/ Low ]
X X i Jet Compressor Suction Flow X High f I
Transport Pipe Hydrogen Concentation X
Jet Compressor Discharge Pressure
'X Cooling Condensate Flow Low X
i Off-Gas Condenser Waterbox Differential High/ Low-X Transport Line Drain Level 1
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TABLE-2 GASEOUS RELEASE-RATE UNDER NORMAL OPERATING CONDITIONS
- Stack Release Nuclide_ (Ci/Yr) j.
Kr-83M 0.
Kr-85M 9.9E+01 Kr-85 1.6E+02~
{t 0,
Kr-87 Kr-88 1.0E+01 Kr-89 0.
Xe-131M 3.0E+00 Xe-133M 0.
Xe-133 1.8E+01 Xe-135M 0.
Xe-135 0. ,
- Assumptions:
- 1) Operating conditions of charcoal bed:
Mass of charcoal = 22,000 lbs (Table'l-1, Charcoal Adsorber Tank Performance Specifications, N30024 H-3, P.V-4)
Temperature of Charcoal bed = -20 F (same as above) l Dew Point at inlet = -90 F (same as~above)
- 2) Adsorption Coefficient for Xe =.5180 CC/gm i
Adsorption Coefficient for Kr = 135 cc/gm
- 3) Number of main condenser shells = 2
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, 4) Activity release rate after 30 minute decay using NUREG 0016 mix = 1
.l 60,000 uCi/sec.
i- j TABLE 3-A NOBLE CAS ISOTOPIC DISTRIBUTION Activity at Activity at i Iso _ tope Reactor No_zzle (u Ci/_S_ec) 30 Minute Delay (u C1/Sec_) l Kr-83m 3.4 x 10 3 2.9 x 10 Kr-85m 6.1 x 10 7 5.6 x 10 1 Kr-85 2.0 x 10 4 2.0 x 10 4 Kr-87 2.0 x 10 3 1.5 x 10 4 Kr-88 2.0 x 10 5 *
- 2' Kr-89 1. 3 x 10 1.8 x 10 Kr-90 2.8 x 10 55 0 Kr-91 3.3 x 10 0 Kr-92 3.3 x 10 45 0 Kr-93 9.9 x 10 4 0 Kr-94 -
2.3 x 10 0 Kc-95 2.1 x 10 3 0 Kr-97 0 Xe.-131m 1.4x10f 1.5 x 10 2 1.5 x 10 2 y
Xe-133m 2.9 x 10 2.8 x 10 Xe-133 8.2 x 10 4 8.2 x 10 3 Xe-135m 2.6 x 10 4 6.9 x 10 4 Xe-135 2.2 x 10 2.2 x 10 2 5
Xe-137 1. 5 x 10 0 6.7 x 10 Xc-138 8.9 x 10 2.1 x 10 Xe-139 2.8 x 10 55 0 Xe-140 3.0 x 10 5 0 Xe-141 2.4 x 10 4 0 Xe-142 7.3 x 10 0 i 4
Xe-143 1.2 x 10 2 - _ 0 Xe-144 5.6 x 10 0 i Total 2.5 x 10 6 1.0 x 10 5
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- l TABLE 3-B RADI0 ACTIVE GAS SOURCE TERM l
l Activity at j Isotope SJAE Nozzle (u C1/Sec) l 1
Br-83 4.6 x 10"
-1 Br-84 9.2 x 10
-1 Br-85 6.3 x 10 j
~1 I-131 1.9 x 10 l 1
0 1 1-132 1.9 x 10 l 0
I-133 1.3 x 10 f 0
I-134 4.0 x 10, 4 i
0 i I-135 3.6 x 10 N-13 6.6 x 10 N-16 1.4 x 10 N-17 1.8 x 10 5
0-19 - - 1.7., 10 i
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TABLE 4 '
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EQUIPMENT DOSE CONTRIBUTIONS Atmospheric Dilution Whole Body Factog Doses Equipment- Release Foint '(sec/m ) (rems)(1) -
a)- Steam Jet Air Ejector ( }. Turbine Bldg 4.62 x 10-4 0.54
~ ~
b) . Process Pipe Turbine Bldg 4.62 x'10 ' 3.15 x 10
~
> c) Recombiner Turbine Bldg '4.62 x 10 '1.20 x 10~
~4 -2 d) Transport Pipe -Turbine Bldg 4.62 x 10 5.81 x 10
-4 ~3-e) Charcoal Beds ( } Xe-Kr Bidg 5.93 x 10 ~7.60 x 10 Total 0.61 l (1) Based upon an offgas system release rate of 350,000 uci/sec at 30 minutes decay.
(2) Assumes 1 hr. operation.
(3) Since the release after 1 hr. will be via the plant stack the dose contribution from these releases will be negligible. Hence only the ground icvel releases need be considered.
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TABLE 5 l
I OFF-GAS PROCESSING SYSTEM OFFSITE DOSE ANALYSIS ASSUMPTIONS Assumptions
- 1) Source Terms: p a) The nobic gas. mixture in General Electric's Report,'NEDO-10734
("the 1971 mixture").
b) A noble gas release rate of 350,000 uCi/see at 30 minutes-decay. ,
I c) Equipment delay times: $
1 Equipment _ Delay Time Process Pipe 2.1 sec.
Recombiner 8.07 sec.
Transport Pipe 9.85 min.
Charcoal beds Xe: 50 days Kr: 1.3 days Line to Stack 12.58 sec. i
' 2) Meteorology:(
a) Groundlevg1X/QjromTurbineBuildingtositeboundary:
4.62 x 10 sec/m b) Groundlevg1X/QjromXe-Kr.Buildingtositeboundary:
5.93 x 10 sec/m
- 3) Dose Calculation Methodology
- I a) Semi-infinite cloud model 1 1
b) Regulatory Guide 1.4 calculation methodology, modified only gamma exposure (since beta doesn't contribute significantly )
to the whole body dose) j i
l (1) Building wake credit assumed, conservative split g calculation !
methodology employed. Based upon on-site meteorological data j 1/1/76-12/31/76. The calendar year 1976 was selected as the data base for accident X/Q calculations because of'a slightly higher frequency of occurrence of stabic atmospheric conditions (E, F- -l and G stability) and light wind conditions (.5 - 1.5 m/sec) in that year compared to 1974 and 1975. These conditions.are those that
- i. cause more conservative X/Q values. l
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l TABLE 6 NORMALIZED OFF-GAS PROCESSING SYSTEM DOSES _
Whole Body Equipment _
Doses (rems)(y) a) Steam Jet Air Ejector 4.45 ,
~3 b) Process Pipe 2.59 x 10
~3 c) Recombiner 9.86 x 10
~
d) Transport Pipe 4.77 x 10
~
c) Charcoal Beds 6.24 x 10 Total 5.00 (1) Calculated based upon a noble gas off-gas system release rate of 2,800,000 uCi/sec at 30 minutes decay.
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TABLE 7 l i
STEAM JET AIR EJECTOR ACTIVITY RELEASE RATE f
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(uCi/sec)
Activity at i f SJAE Nozzle -
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Isotopc( (uCi/sec)
KR-83M 1.19E+4( }
KR-85M 2.14E+4 ,
l KR-85 35-70 KR-87 7.00E+4 KR-88 7.00E+4 l 1
4.55E+5 j KR-89 XE-131M 5.25E+1 XE-133M 1.02E+3 1
XE-133 2.87E+4 )
l XE-135M 9.10E+4 XE-135 7.70E+4 XE-137 5.25E+5 XE-138 3.12E+5 I-131 1.95E-1 1-132 1.95E+0 1-133 1.33E+0 1-134 4.05E+0 1-135 3.58E+0 (1) Based on a source term of 350,000 uC1/sec nobic off-gas release rate at 30 minutes decay.
(2) Only 'those radiologically significant isotopes have been included (i.e., only those isotopes with half-lives of greater than 1 minute have been considered).
(3) Denotes power of ten, nn
-- - q e .
y l-. 1
- I
/
l TABLE 8 RADIONUCLIDE INVENTORY IN THE OFF-GAS PROCESSING SYSTEM (l Activity _(uCi)( _
Equipment:
l Isotope Process Pipe _ Recombiner Transport Pipe _ Charcoal Beds l KR-83M 2.50E+04 9.59E+04 6.81E+06 1.07E+08 KR-85M 4.48E+04 1.72E+05 1.24E+07 4.70E+08 KR-85 1.47E+02 5.64E+02 4.13E+04 7.92E+06 <
KR-87 1.47E+05 5.64E+05 3.95E+07 4.20Ef08 KR-88 1.47E+05 5.64E+05 4.05E+07~ _9.79E+08 KR-89 9.51E+05 3.59E+06 1.07E+08 1.42E+07 XE131M 1.10E+02 4.23E+02 3.10E+04 7.31E+07 XE133M 2.13E+03 8.18E+03 5.99E+05 2.85E+08 XE-133 6.02E+04- 2.31E+05 1.69E+07 1.88E+10 XE135M 1.91E+05 7.30E+05 4.32E+07 7.85E+07 XE-135 1.62E+05 6.21E+05 4.52E+07 -
3.64E+09 XE-137 1.10E+06 4.16E+06 1.42E+08 2.97E+07 XE-138 6.53E+05 2.50E+06 1.50E+08 3.04E+08 BR-83 3.38E-01 1.30E+00 9.28E+01 1.91E+03 BR-84 6.76E+00 2.59E+01 1.70E+03 7.11E*03 BR-85 4.61E+00 1.74E+01 4.93E+02 5.62E+01 I-131 1.40E+00 5.36E+00 3.92E+02 6.67E+05 I-132 1.40E+00 5.26E+01. 3.83E+03 7.57E+04 I-133 9.55E+00 3.67E+01 2.68E+03 4.93E+05 1-134 2.94E+01 1.13E+02 7.73E+03- 5.52E+04 I-135 2.64E+01 1.02E+02 7.37E+03 4.33E+05
~
SUM 3.48E+06 1.32E+07 6.04E+08 2.52E+10 (1) Based on a nobic gas off-gas system release rate of 350,000 uCi/sce ]
at 30 minutes decay. ;
(2) Only those radiological significant isotopes have been included (i.e., only those isotopes with half-lives of greater than 1 minute have been considered).
(3) Denotes power of ten.
l l
i 3
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