GENII Version 2 GENII Version 2 General Purpose Environmental General Purpose Environmental Radiation Software Radiation Software PNNL: Bruce Napier, Dennis Strenge, Van Ramsdell, Christian Fosmire, Mitch Pelton For EPA Office of Radiation and Indoor Air: Chris Nelson, Dale Hoffmeyer, Sanjib Chaki, Tony Wolbarst, Kathryn Snead
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GENII Version 2 General Purpose Environmental Radiation Software PNNL: Bruce Napier, Dennis Strenge, Van Ramsdell, Christian Fosmire, Mitch Pelton For.
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GENII Version 2GENII Version 2General Purpose EnvironmentalGeneral Purpose Environmental
Radiation SoftwareRadiation Software
GENII Version 2GENII Version 2General Purpose EnvironmentalGeneral Purpose Environmental
Radiation SoftwareRadiation Software
PNNL: Bruce Napier, Dennis Strenge, Van Ramsdell, Christian Fosmire, Mitch Pelton
For EPA Office of Radiation and Indoor Air:
Chris Nelson, Dale Hoffmeyer, Sanjib Chaki, Tony Wolbarst, Kathryn Snead
Support from ORNL: Keith Eckerman
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GENIIGENIIGENIIGENII
A set of computer programs for estimation of radionuclide concentrations in the environment and dose/risk to humans from:Acute or chronic exposures toReleases to surface water or atmosphere,
orInitial contamination conditions
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GENII V.2 in FRAMESGENII V.2 in FRAMESGENII V.2 in FRAMESGENII V.2 in FRAMES
GENII development history
Available Models
Atmospheric transport
Surface water transport
Waste/soil redistribution
Terrestrial uptake
Human Exposure
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GENII V.2 in FRAMES, ContinuedGENII V.2 in FRAMES, ContinuedGENII V.2 in FRAMES, ContinuedGENII V.2 in FRAMES, Continued
Dose/Risk
Uncertainty/Sensitivity
Capabilities and limitations
Walk-through some examples
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GENII DevelopmentGENII DevelopmentGENII DevelopmentGENII Development
1988 - Version 1. Released ICRP-26/30/48 dosimetry
Lagrangian puff based on 1 observation pointHourly time step using hourly observations or quasi-hourly
inputs derived from joint-frequency dataSingle sourceSquare gridGround-level or elevated releases
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Parameterizations for Diffusion CoefficientsParameterizations for Diffusion CoefficientsParameterizations for Diffusion CoefficientsParameterizations for Diffusion Coefficients
Dry deposition“Resistance model”Includes gravitational settling of larger particles
Wet depositionWashout dependent on precipitation rateRain and snow considered
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GENII V.2 Air Submersion Dose RatesGENII V.2 Air Submersion Dose RatesGENII V.2 Air Submersion Dose RatesGENII V.2 Air Submersion Dose Rates
Infinite plumeBased on Federal Guidance Report 13 models
Finite plumeClose to release - array of line sourcesIntermediate distances - stacked series of infinite planesLong distances - defaults to infinite plume
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Sources of Data for Atmospheric ModelsSources of Data for Atmospheric ModelsSources of Data for Atmospheric ModelsSources of Data for Atmospheric Models
Hourly data CD-144 format (National Climatic Data Center) SAMSON format (NCDC)
1st order stations 1961-1990 on 3 CDs, also a later one
Precipitation in TD-3240 format (NCDC) (For sites in the US, these are now available online from either NCDC
or EPA/CEAM)
Joint frequency data STAR (ISC-3) [provided for many US sites] GENII V.1.485
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GENII V.2 Surface Water Transport ModelsGENII V.2 Surface Water Transport ModelsGENII V.2 Surface Water Transport ModelsGENII V.2 Surface Water Transport Models
Simple models derived from NRC’s LADTAP codeRivers - analog to atmospheric gaussian plume
GENII V.2 Tritium Specific Activity ModelGENII V.2 Tritium Specific Activity ModelGENII V.2 Tritium Specific Activity ModelGENII V.2 Tritium Specific Activity Model
Environmental media assumed to have same specific activity (Bq/kg water) as contaminating medium (water or air)
Fractional content of both water and non-water portions of the food product is used
In acute cases, rapid equilibration / de-equilibration is assumed (~8 hours)
Based on observations at Chalk River
Includes organically-bound tritium as a “progeny”
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GENII V.2 Carbon-14 Specific Activity ModelGENII V.2 Carbon-14 Specific Activity ModelGENII V.2 Carbon-14 Specific Activity ModelGENII V.2 Carbon-14 Specific Activity Model
For atmospheric sources, model is parallel to that for tritium
For water sources, equilibration is assumed with soil carbon atom ratios
For acute cases, uptake via photosynthesis is slow, long de-equilibration
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GENII V.2 Human ExposureGENII V.2 Human ExposureGENII V.2 Human ExposureGENII V.2 Human Exposure
Up to 6 age groups allowed, following ICRP-56,67,69
GENII V.1.485 presented results for 4 seasons (Winter/spring/summer/autumn)
GENII V.2 now also includes time-dependent model based on the V.1.485 approach – keys off of time of year from meteorological calculationsThis adds more variability to projected answers, and is
EPA Health Effects Assessment Summary Tables (Currently the same as FGR 13)Ingestion (risk/pCi ingested)Inhalation (risk/pCi inhaled)Ground plane external (risk/year per pCI/g)
Parameter uncertainty and sensitivity may be addressed using the SUM3 processor in FRAMES.
All non-control parameters are allowed to be varied, using description files to define ‘available’ parameters
Acute atmospheric releases are an important subset. For these, SUM3 is used to vary start times in the plume or puff models, allowing construction of the location or site cumulative dose/risk distribution function.
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Use of SUMUse of SUM33 to get CDF of Dose to get CDF of DoseUse of SUMUse of SUM33 to get CDF of Dose to get CDF of Dose