DRAFT
GENII Version 2
Example Calculation Descriptions
For Advisory with
EPA's Science Advisory Board
Radiation Advisory Committee
April 25,2000
&EPA
DRAFT
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A
GENII Version 2 Example
Calculation Descriptions
B. A. Napier
January 1999
Prepared for
U.S. Environmental Protection Agency
under Contract DE-AC06-76RLO 1830
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Introduction
A series of nine sample problems are described to illustrate the range of capabilities of
the GENII Version 2 radiation dose calculation methodology. The sample problems
individually cover a limited range of the overall capabilities, but in aggregate they show
the wide range of possibilities that the GENII system is designed to address.
Only a brief description of each sample problem is provided here. It is assumed that the
reader will follow along with each example using the Framework for Risk Analysis in
Multimedia Environmental Systems (FRAMES) environment on an appropriate
computer.
This brief description is a companion to three other user aids;
B.A. Napier, D.L. Strenge, J.V Ramsdell, P.W. Eslinger, and C. Fosmire. 1999. GENII
Version 2 Software Design Description, Pacific Northwest National Laboratory,
Richland, Washington
B.A. Napier, D.L. Strenge, J.V. Ramsdell, Jr., P.W. Eslinger, C. Fosmire, K.J. Castleton,
and M.A. Pelton. 1999. GENII Version 2 Users' Guide, Pacific Northwest National
Laboratory, Richland, Washington
G. M. Gelston, M. A. Pelton, K. J. Castleton, B. L. Hoopes, R. Y. Taira, P. W. Eslinger,
G. Whelan, P. D. Meyer, and B. A. Napier. 1998. GENII Version 2
Sensitivity/Uncertainty Multimedia Modeling Module User's Guidance, PNL-12036,
Pacific Northwest National Laboratory, Richland, Washington
Example 1
The FRAMES view of Example 1 is illustrated in Figure 1. The GENE files for this
example are provided under the filename of EXAMPLE l.GID.
Example 1 is a simple case analyzing an occurrence of initial surface soil contamination.
An individual is assumed to reside in the vicinity of the soil contamination and to be
exposed via direct irradiation, inhalation of resuspended materials, and ingestion of crops
and animal products raised in the soil.
The following radionuclides are assumed to be in the soil:
Cs 137 1000 pCi/kg
Pb210 2000pCi/g
Bi210 2500pCi/g
Po210 2750pCi/g
Pu239 3000pCi/g
Sr90 4000pCi/g
Y 90 4500 pCi/g
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I
7*.
gy*i»»ni»tfi«a -
Figure 1. FRAMES view of Example 1
The Csl37 is included as a representative high-energy gamma ray emitter and as a
representative of a class of radionuclides handled in GENII Version 2 as having "implicit
decay progeny." Csl37 is almost always associated with its decay progeny Bal37m,
which has a half-life of about 2 minutes, and in environmental situations can be
considered to be in equilibrium with the parent Csl37. In GENE Version 2, implicit
progeny are included by assuming that all of their decay energies are associated with the
parent radionuclide.
The Pb 210 is included as the parent of a multi-member radiological decay chain. In this
case, it is the parent of the Bi 210 and Po 210. The progeny are both of shorter half-life
than the parent, but each may have its own unique environmental behavior following
release into the environment However, the progeny are also continuously produced by
the parent, and so may have a relatively complex environmental behavior.
The Pu 239 is included as a representative of a long-lived alpha emitter. The dosimetry
of the alpha emitters is more complex than that of the beta and gamma emitters in the
GENII health impacts calculations.
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The Sr 90, and progeny Y 90 are included as representative pure beta emitters. They also
represent an explicit chain. In GENII Version 2, the dividing line between implicit and
explicit progeny is drawn at half-lives of 10 minutes or greater.
The soil contamination is defined in the FRAMES Known Source Concentration module.
This module is illustrated in Figure 2; this module is the left-most icon in the chain in
Figure 1. GENII does not use the information in the first four items in the upper left hand
corner of the frame, but it is necessary to enter information to complete this user
interface.
The FRAMES Known Source module includes one useful feature under the Option tab; it
allows the input of concentrations of decay progeny of radionuclide parents selected in
the Contaminants Selection module. This option is selected, which activates the small
double-arrow switch to the right of the label "Parent" above the input boxes.
For initial soil contamination, it is only necessary to input a soil concentration at a single
selected time. When the initial soil sources are selected, the FRAMES source file
generator may be run, and the results viewed with the Soil Contamination File (SCF)
Viewer.
FRAMES Known Source Module
FBe Options Reference
, | C
J
, E
1
1
1
?n3 PnntArTuruttinnli
__..,, .»- . * __— , , ....
Type of contaminated medium
\A/iCRh of contanvnated son
Length of contaminated sol
Depth of contaminated soil
CESIUM-137+D 13 "
time fbat Rate
yi IT pCi/kg 1*
0 1000.
i
„ . . . . „_ ^ „ r „
Vadose Ijj
10 !m i^'ReftO
JkO. ... Jm ^JR*0
jl.O -_|m /iJHef.O
ef: 0
~ «,
7T
D;',
4-
13.
1*
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Figure 2. Input soil concentrations to FRAMES Known Source Module
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The GENII Near Field environmental accumulation and exposure module is then
selected. The main screen is illustrated in Figure 3. It is important to indicate which soil
compartment is to be attached to the FRAMES Known Source Module. This is done
using the Surface Soil Source input box. (Other soil compartments may be activated at
the same time; if more than one FRAMES source is selected, several different spectra of
radionuclide contamination may be input to one case in different soil compartments.)
The box has a pull-down menu activated by the arrow on the right-hand side of the box.
Other parameters may be selected as desired to customize a case. Note that it is logical
that the fraction of roots in surface soil and the fraction of roots in deep soil
(Agriculture/General tabs) should add to a value less than or equal to one. This ensures
mat the plants are not over exposed to contaminants. However, in a case such as this one,
where only one soil compartment is contaminated, the roots in the uncontaminated soil
will not contribute to the uptake.
In Example 1, the exposure is defined to last for 5 years (Exposure Duration variable on
the main input page). Thus, the remainder of the codes will deal with five groups of
annual data.
S5fcm3 - GENII Near Field Exposure Module
jf File Defaults Reference Help'
|» Controls
I
Ret 0 fjgiAnimal pfod^jJojatjon!
Ref: 0 |5F Terrestrial Food crop Digestion
RefrO pDebugtesting
IQ-P
Time from start to exposure
Duration of exposure period
End of release period |i rj
Loss of institutional control time prior to exposure
Absolute humidity, used arfy for tritium model
Surface soil source
Deep sol source
Waste package soil source
Waste package haff Be
Ref: 0
Figure 3. Primary parameter selection in GENII Near Field Module
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The next major selection is the GENII Receptor Intake module. The main screen is
illustrated in Figure 4. Up to 6 age groups may be selected; in Example 1, only a single
age group representing a 70-year lifetime is chosen. For each age group, all of the
parameters must be chosen. Default values are provided for average individuals and
maximally-exposed individuals. These defaults may be selected by toggling the
selections using the "Defaults" tab at the top of the screen.
|rflicp4 - GENII Intake Module
Re Qefaufts Reference
Number of age groups
' I
i 1
{ I
Age group selector)
Years in age group
ITO.O
Population in age group
|1.0 (none F]Ref:
Pathway selection
^^^^^gH^^^^^g^m^i
External ground exposure
External exposure while swimming
External exposure while boabng
External exposure to shoreline
Food crop ingeston
Animal product ingestion
Aquatic food ingestion
Drinking water ingestion
Water ingesbon whde swimming
Water ingesbon while showering
Inadvertent soil ingesbon
Air inhalation
0
'External exposure to air1^ — = —
Daily plume nmersion exposure tone
240 jhr [!
Y&flriy plume ffrmsfston dxpGjSucp linw
J365.0 (day _ijj Ref:
Figure 4. GENII Receptor Intake module main screen
In Example 1, the GENII Health Impacts module is used to estimate the committed
effective dose equivalent to the exposed individual using ICRP Publication 30 dosimetry.
This is done by selecting ICRP 30 on the Method Selection tab, and CEDE on the
Method Parameters tab. The selection on the Method Parameters tab is shown in Figure
5.
Note that in this module, suggestions and/or help scrolls across the bottom of the screen
when a selection is triggered.
This completes the data input necessary for Example 1. The intermediate and final
results may be viewed with the appropriate viewers attached to each module.
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jV,,GENII Health Impacts Module - hei5
:j File Peferer.cc Help
Method Parameters |_
',' Calculate fifetane cancer incidence
jSOs-2
17' Calculate cancer fatalities
ConveiJor.rsclcw 15 Qe-2
Irisk/Sv F
jnsk/Sv
- -
: Ref:
IxjCJaiajiate'radaton effective ose equivaent com^tfent {CPj
Thickness of contaminated sofl/sediment layer - IQ.04 |
cniiT I_"- - - ._!
SOILT
Density of contaminated soil/sediment layer- Ffs|kg/m*3 JF] "* ^
] Calculate radiation effective dose equivalent commitment (CEDE), dick to enable
Figure 5. GENII Health Impacts module Method Parameters tab
Example 2
Example 2 is similar to Example 1, but the source is contamination in deep soil rather
than surface soil. This example was created by editing the Global Input Data (GID) file
for Example 1. The major change is selection of Deep Soil Source in the Near Field
module (see Figure 3).
The only other change is that this scenario assumes that the individual living at the site
intrudes into the buried material and mixes some of it with the clean surface overburden.
This is modeled using a manual redistribution factor. The manual redistribution factor is
a ratio of the final mixed surface concentration to the initial deep soil concentration. For
Example 2, it is assumed that the final surface soil concentration is 25% of the initial
deep soil concentration. The initial concentrations in the FRAMES Known Source
module are the same as for Example 1. The manual redistribution factor is set as shown
in Figure 6. The value determined for the scenario is entered into the box at the bottom
of the Soil/Description tab.
All other parameters in this example are set to the same values as Example 1. It can be
seen by viewing the various intermediate and final results files that all concentrations and
doses are one-quarter the magnitude as those in Example 1. This is a direct result of the
use of 0.25 in the manual redistribution factor.
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ES?fcrn3 - GENII Near Field Exposuie Module
Fie Defajfts
'Controls
._Leachina
Befeje-ios Help
Ref: 0 n Bntic transport from deep soil to surface so3
RefcO fj DO twotic transport prior to start of intake
Ret 0 O Arid drmele during aeriod prior to intake
Surface soil area) density
Surface sod density
Surface soB layer thickness used for density
Depth of soil overburden over waste
Thickness of buried waste layer
Source area for external dose rnodSfcation factor J12500JnT2j^J
Manual redistribution factor |fj.25 J fraction
0
Figure 6. Description of soil contamination conditions in Example 2
Example 3
Example 3 illustrates use of the GENII Surface Water transport module. This example
simulates a chronic release of radionuclides into a medium sized river.
After the contaminants are selected, the FRAMES Known Source module is again
selected. The rate of release to the river is defined. In this module for contaminant
releases (as opposed to initial soil conditions), the source may be time varying, and the
variations may occur at any time scale. GENII will integrate the releases over the
necessary scales to prepare annual average release rates. For this example, a simple
square wave is defined starting at time zero and continuing for one year. In the source
module, it is not necessary to explicitly indicate an end to the release unless desired. The
codes will assume that the release ends after the final time increment entered.
In Example 2, the option of using a source viewer is illustrated. The FRAMES source
"chart" viewer is attached to the source module. This viewer spawns an EXCEL
spreadsheet to prepare a graphical presentation of the source release rate and cumulative
release of each radionuclide with time.
Select the GENII river dispersion model using the pull-down box on the main Surface
Water module screen as illustrated in Figure 7. The type of model is selected from the
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iiv3 - GENII Surface Water Module
File Reference Help
Type of release and body of water
Duration of the release to the surface water
Usage Location
Travel time in surface water
Total volumetric Row rate of river for location
I Chronic Row Dilution
111 |yr
|GENII_Chronic(fcrn4j
~
|5*0
(Value must be > 0 and <= 50000 0 rrT3/s(s).
Figure 7. GENII Surface Water input
Pull-down box. Example 3 is a chronic flow dilution model. Note that suggestions and
parameter ranges scroll across the bottom of the screen.
The GENII chronic exposure model is connected to the surface water transport module.
It is necessary to indicate the source of contaminated water in this module in the
Water/General tab as shown in Figure 8. This is also required under the Water/Irrigation
Sources tab for all selected pathways.
Note on the Pathways tab that it is not possible to select atmospheric-transport-related
pathways, they are made unavailable because a surface water source is attached to the
module.
For Example 3, the Maximally-exposed individual parameters are selected from the
default files in the GENII Receptor Intake module. Only one age group is again selected.
For Example 3, the GENII Health Impacts module is used to select estimation of cancer
incidence using EPA slope factors. No other input parameters are required in the Health
Impacts module for this selection.
Example 4
Example 4 is very similar to Example 3, but an acute release to the river is simulated.
The release rates are the same as Example 3, but the release time is selected to be 0.001
year (about 8 hours).
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fcm4 - GENII Chronic Exposure Module
Fie Defaults geference Help
Controls Water ] Sofll Agriculture I Pathways
General j Animal watei) Irrioation sources 1 Inioation rates ] Inioation tones]
RefcO lx Aquatic foods from salt watei
RefrO jx Treatment plant purification c
Ref: 0 pc Residential irrigation
Source of residential nigabon
Irrigation rate for residential land
Irrigation time for residential land
Irrigation water deposition time prior to expos
Source of domestic water
Indoor volatilization factor for radon
Indoor volatilization factor for radnnuddes
Delay time in water distrbution system
.haeSr^yulmertdamilj.
(vesus fresh watei)
if domestic water
JSurfacewater
[None
^BflnffBrml
|6.0
«e |ao
jSurfacewater
I01..
|0.0
jl.0
1 15.0
j RefcO
^^^1 Ref- 0
JmSd Ref: °
\y J Ref: °
J RefcO
Jl/m"3 d Reft °
N*? d Rrf °
Jd^ J Hrt °
Ikg/m^jj Heft °
i
Figure 8. Selection of surface water sources in GENII Chronic Exposure module
Example 4 requires use of the GENII Acute environmental accumulation and exposure
module rather than the chronic one as in Example 3. Similar pathways are selected as
Example 3. The GENII Receptor Intake module parameters are the same as Example 3,
as is the selection of EPA slope factors in the GENII Health Impacts module.
The risk results of Example 4 may be compared to those of Example 3. Because the
release rate was assumed to be the same as Example 3, but for only 0.001 year, only
0.001 times as much radioactive material is assumed to be released. Those risks that are
directly related only to the total release are seen to be 0.001 times the size of those in
Example 3. However, some of the other pathways, which are not linearly related
(because weathering and other factors cause differences) are not obvious multiples of the
Example 3 results.
Example 5
Example 5 illustrates the use of GENII to model radiation doses and risks resulting from
a chronic release of radionuclides to the atmosphere. In this example, the chronic
straight-line gaussian model is used.
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.-r. FRAMES Known Souice Module
Reference:
;p Atmospheric FJux
1
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i
1
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r
'
i:
t
h
1 -
TW
Exi
ExJ
He
ExJ
Exi
Am
Par
» of release
t area of source
height of source
ghl of adjacent structure
velocity of source
temperature of source
lient air temperature
ent |r
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(Atmospheric Release
_ _ _
HGasI
rluv density
(x Partictel
Particle radius
! Flux density
riParticle2
Particle radwi
Buy density
Particle jadvjs
Flax dencty
Flux Types
» ^ , . _.:
I15
IU_..
!!?_-_
I?".
|lb
• lit—
lib
1
£ - -. * . .
1 g/crrT3 rj ^e*- "
Jum PJ Ref:0
,,i?^a.yRef:o
lum |*J, HetO
~ -f ^^u. -TT1,
1 1 ** *"i 1^1 f"tff«f* El
Jg/cm 3 ITJ nef- °
^J'S^Jd"*0
|g/cm'3 Fl fief:0
— .- -
AddRef "1
| SetectRet ]
L |!5!S 1
Figure 10. FRAMES Known Source module Flux Type screen
Object General Information
Object Type: !=«?«« ?«**«».* ....... ^J
, Name: Jf«n4.
Select from Appicable Models
-*!-.» &f. ^TT *«r' J-M
InstaBatnn Relative Easting ^
Installation Relative Northing
Elevation
Model Description
1 km
Non-appEcable Models
GENI1 Near ci=iu E
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While selecting the GENII Chronic Exposure module to connect with the Chronic Plume
module, it is possible to define where the receptors are located. In Example 5, a 'relative
easting" and "relative northing" of (0,0) is chosen. This selection is in the upper right
comer of the screen. When this combination (indicating the center of the grid) is
selected, the Chronic Exposure module will estimate concentrations at all locations on the
gnd. This selection is illustrated in Figure 11. Additionally, in Example 5, the Finite
Plume air submersion dose model is selected in the GENII Chronic Exposure module.
With this selection, the EPF file contains dose rates for each location, rather than air
concentrations.
The GENII Receptor Intake module is used in Example 5 with the maximally-exposed
individual default parameters. The Health Impacts module is run with ICRP-30
dosimetry. It also uses a dose-to-cancer-incidence conversion factor and provides cancer
estimates.
Example 6
Example 6 uses the same source release rate as Example 5, but for a period of only 0.001
year (about 8 hours). Therefore, a different plume model is used - the GENII Acute
gaussian Plume model is selected. This model also runs on hourly data. For this
example, the last hour of data in the year supplied in the input file is used. In this way,
persistence is used and the plume travels in a straight line for the entire period. This
makes the result compatible with Example 8, described below.
Like the chronic case in Example 5, all other parameters are kept as constant as possible.
Notice that the GENII Acute Exposure module must be used with the Acute transport
module.
Because the case has been structured so that the plume goes only one direction (north),
there are a large number of zeros in the dispersion output file, and as a result, a large
number of zeros in the exposure, intake, and dose results. (EPF, RIF, and HIF files).
Example 7
Example 7 is the same as Example 5, except the GENII Chronic Lagrangian Puff
atmospheric transport model is used. This module is very data and computationally
intensive, but provides the best use of available data. This example shows how the puff
and plume models compare, (compare the files EXAMPLES .ATO and
EXAMPLE7.ATO).
For Example 7, a single receptor is selected. The receptor is assumed to live 14.4 km
northeast of the release point. This is input using the "relative northing" and "relative
easting" parameters at 10 km each (102 plus 102 equals 14.42). See Figure 12. Use of a
single receptor location greatly reduces the size of the subsequent output files.
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Object General Information
Object Type
Label*
Name.
Instalation Relative Easting Pu ...
Instalahon Relative Northmg I™
Elevation
1°
km
km
Select fromAppfcabte Models
Model Description
ire Module
Non-appbcdbie Models
Near F'eta Exposure vodule
Mepas i 0 Cvonic Exncsure Mo-u a
GENII Chronic Exposure Module
The GENII chronic exposure module may
be used to estimate concentrations in
exposure media for groundwater. surface
water, and atmospheric transport pathways
The analysis accepts time-varying
concentration data for waterborne pathways,
and annual average atmospheric transport
values. Deposition to sod from air or
irrigation may be considered prior to the
start of the exposure period. The results
of the analysis are written in annual
increments for the duration of exposure
defined by the user. Exposure pathways
include domestic water use (including
irrigation of home gardens], agricultural
product consumption, aquatic food consumption.
Cancel
Figure 12. Using easting and northing to place a specific individual
In the Chronic Exposure module, the Infinite Plume submersion dose is selected.
The dosimetry for Example 7 is based on ICRP Publications 60 and 72. This results in
doses printed to the HIF file for numerous organs and tissues, as well as the effective
dose.
Example 8
Example 8 is similar to Example 6 (and 5 and 7) - it is an acute atmospheric release
modeled with the GENII Acute Lagrangian Puff model. Like Example 6, the hourly
meteorology is selected to start at midnight on December 31, 1988, so that the plume runs
straight.
A single location is selected, this time 10 km due north (in the direction of the wind).
ICRP 60 and 72 doses are calculated, as is risk using Federal Guidance Report 13. Note
that the "Method Parameters" input tab requires dose-to-risk conversion factors even
though FGR 13 risk factors are used. This input is needed for doses resulting from
potential exposures to contaminated water, for risk conversions are not published in
14
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;.ft GENII Health Impacts Module - hei6
£te Reference Help
!, Constituent Paametgsj|
Constituent -FS-CNAME I^SIUM-137+D
Intake to Mood transfer fraction - Fl
Particle aze-AMAD
Lung transfer inhalation class » SOLUBIL
fi I fraction H; Ref" °
"'^
Figure 13. Health Impacts Constituent Parameters tab
FOR 13. Note also the "Constituent Parameters" tab (Figure 13). The dosimetry allows
definition of blood-to-gut transfer factors, particle size, and lung transfer class. At this
time, only the lung transfer class and fl parameters are active, and those only for the dose
conversion factors. Additional dose factors and risk factors are anticipated from Oak
Ridge National Laboratory to expand the capabilities of these calculations.
Example 9
Example 9 is an expansion of Example 8 to illustrate the use of the SUM3 processor to
estimate uncertainty. The SUM3 processor is connected to the source term module and
the dosimetry module. In this example, the source term is varied, and the resultant
variability of the doses is estimated.
The variability in source term is established following the directions in the SUM3 manual.
This is illustrated in Figures 14 and IS, which show how the variables are selected and
distributions associated with them.
Note that at this writing, the SUM3 processor requires some upgrades to make it
compatible with evolving HIF file formats. It is not possible to select output doses at this
time. However, the SUMS system does function, and multiple replicates are possible.
The SUM3 viewer also provides example graphics of the input variables.
15
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Sensitivity/Uncertainly Multimedia Modeling Module - sen! 2
Variable*
T
Parameters
Outputs
Aias
Delete
Description |Conlaminanl or Watei Rux Rate foi. Med-a 3, enoi. Tone Index 2 from Ab_teteas8{sr
Aias Variable Description
c4
Tine
Tine
Tine
Time
Tine
Tine
Tine
Tine
Tine
Cor,
Cor,
Cor,
Cor,
Cor/
Cor,
Cor,
Cor,
Cor,
Hedia
Hedia
Hedia
Hedia
Hedia
Hedia
Hedia
Hedia
Hedia
Contaminant 01 1
3,
3,
3,
3,
3,
3,
3,
3,
3,
error
error
error
error
error
error
error
error
error
/
/
/
t
§
t
t
t
g
rater Flux
ContamLnant or Hater Flux
ContarrLnant or Hater Flux
Contflpfl ra*11^ or Hater Flux
Tine
Tine
Tine
Tine
Tine
Tine
Tine
Tine
Tine
Rate
Rate
Rate
Rate
Index
Index
Index
Index
Index
Index
Index
Index
Index
0
0
0
0
0
0
0
0
0
Cron
Cron
LL'Ol'l
Cron
Cruui
Croxi
Cron
Cron
from
for , Media 3 ,
Cor, I
fed
lia 3,
Cor, Hedia 3,
Cor, I
ted
Ha 3,
lir_releas.d
air_releas:
air_releas"
air_releas
air releas'
air releas
fiir_releas
air_releas
air releas—
error, TiM
error , Yii<
error , Ti
error, TiSJ
Figure 14. Selection of contaminant variable
Sensitivity/Uncertainty Multimedia Modeling Module - sen 12
Variables
J
fwaMhn
Outputs
Aias
InpU Variable Description
(Contaminant or Water Rux Rate for. Media 3. error. Trme Index 2 from
!Dirtribu6oni I Correlations T Equation
[Log Normal
Upper bound (inear)
Lower bound linear)
Mean tog
Standard devi&tMkt log
Log Base
|1 OOE*14 jpO/yr J
|100E*11 fi5a/yr 3
| POM 3
"|pCyyr j
it Q
Figure 15. Selection of parameter distribution
16
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