# Presentation: 863235

## Workshop
U.S. Nuclear Regulatory Commission
Rockville, Maryland

Pacific Northwest National Laboratory
November 15-17, 2005

- U.S. Nuclear Regulatory Commission
- Rockville, Maryland
- Pacific Northwest National Laboratory
- November 15-17, 2005

**GENII Version 2.0****Overview and Examples**

**Notes:**
Welcome to Pacific Northwest National Laboratory.

## GENII

- A set of computer programs for estimation of radionuclide concentrations in the environment and the resulting dose and/or risk to humans from:
- Acute or chronic exposures to
- Releases to surface water or atmosphere, or
- Initial contamination conditions

## Types of Scenarios

- A scenario is a conceptual model that describes patterns of human activity, events, and processes that result in radiation exposure to people.
- Far-Field scenarios
- Atmospheric transport (Acute or chronic)
- Surface water transport (Acute or chronic)
- Near-Field scenarios
- Spills
- Buried waste
- (Groundwater use - GW transport modeling is NOT an explicit part of GENII)

## GENII Timeline

- Dose Period

- Release Period

- Residual Period

- Optional inventory
- decay/biotic transport
- period

- Release
- or
- disposal

- Intake/exposure
- begins

- Release
- stops

- Intake/exposure
- ends

## Uncertainty Analysis

- 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

## Dose Calculations

- External dose rate conversion factors from Federal Guidance Report 12, provided by Keith Eckerman, ORNL
- Air Submersion
- Water Immersion
- Soil Plane
- Soil Volume
- Internal Effective dose equivalent:  ICRP-30
- Adult only
- Internal Effective dose: ICRP-72
- 6 age groups
- 24 organs/tissues
- Inhalation classes F, M, S

## Risk Calculations

- EPA Health Effects Assessment Summary Tables (Currently the same as FGR 13; for population exposure = adults)
- Ingestion  (risk/pCi ingested)
- Inhalation (risk/pCi inhaled)
- Ground plane external (risk/year per pCi/g)
- Dose-to-Risk Conversions; estimates of cancer incidence and mortality in relation to effective dose
- Risk = Dose (Sv) * Conversion (risk/Sv)
- Federal Guidance Report 13 coefficients for 15 cancer sites
- Inhalation  (risk/Bq)
- Inhalation classes F, M, S
- Ingestion  (risk/Bq)
- Accounts for different consumption patterns with age
- Drinking water
- Food crops

## GENII Limitations

- Up to 100 radionuclides may be considered in one case
- Decay chains are limited to 9 members (be careful not to use the MEPAS RMDLIB.DAT file)
- Radon diffusion model not yet implemented in Near Field model
- GENII V.2 is still in testing – report problems!

## GENII DemonstrationReplication of the CAP-88 PC Sample Problemas Described in the GENII v2 User’s Guide

- 6 co-located emission points in CAP-88 example and GENII only allows 5 locations.

|  | Source 1 | Source 2 | Source 3 | Source 4 | Source 5 |
| --- | --- | --- | --- | --- | --- |
| Area (m2) | 0.13 | 0.17 | 0.26 | 0.05 | 0.13 |
| Height (m) | 15.24 | 15.24 | 15.24 | 7.62 | 10.0 |
| Exit velocity (m/s) | 13.5 | 9.25 | 19.54 | 7.94 | 15.04 |
| Release (Ci/yr) |  |  |  |  |  |
| U-234 | 2.4E-4 | 3.2E-4 | 3.2E-9 | 9.6E-13 | 2.7E-8 |
| U-235 | 1.7E-6 | 2.3E-6 | 8.0E-7 | 5.5E-6 | 3.4E-5 |
| U-236 | 0 | 0 | 0 | 0 | 1.8E-6 |
| U-238 | 2.4E-4 | 3.2E-4 | 4.0E-4 | 7.6E-4 | 3.6E-3 |

## Conceptual Model

## Entry of the source term data for Source 1.

## Define the radial atmospheric transport grid.  There are 12 distances used in CAP-88 example and only 10 distances available in GENII.

## Joint Frequency Distribution is available for Erie, PA and Precipitation is available for Buffalo, NY.

## For this example, the exposure occurs from years 99 to 100.

## For this example, most of the GENII default intake values are suitable.

## GENII Walk-Through

- Example demonstrating key user interfaces
- Radiation dose to adult individual from chronic release to surface water and aquifer

## Example Description

- 15-year known (i.e., user defined) chronic release to surface water
- 0.25 pCi/ml Am-241 & 2.5 pCi/ml Pu-239
- 100-year known (i.e., user defined) chronic release to aquifer
- 0.1 to 0 pCi/ml Am-241 & 1 to 0 pCi/ml Pu-239
- Local agriculture includes: beef, milk, leafy and root vegetables, fish
- Other pathways include drinking water, inhalation of indoor air, resuspended soil, external exposure to soil
- Remaining parameter values are selected by the analyst to meet needs of site-specific analysis.

- Select the GENII Radionuclide Database Selection

- Select the _user defined_ WCF Surface Water Module because the surface water _concentrations_ are known

- Select the _user defined_ WCF Aquifer Module because the aquifer water _concentrations_ are known

- Because this was a chronic release, select the GENII V.2 Chronic Exposure Module for environmental accumulation

- Select the _MEPAS_ 5.0 Receptor Intakes Module.  At this time, the GENII V.2 Receptor Intake Module is not compatible with FRAMES 2.

- For comparison exercise, select both the GENII V.2 Health Impacts Module and the MEPAS 5.0 Health Impacts Module.

- For comparison exercise, select both the GENII V.2 Health Impacts Module and the MEPAS 5.0 Health Impacts Module.

- Enter constant surface water concentrations (i.e., 0.25 pCi/ml Am-241 & 2.5 pCi/ml Pu-239) over 15-year period.

- Select these arrow buttons to view and enter information for remaining constituents

- Enter time-varying aquifer concentrations (i.e., 0.1 to 0 pCi/ml Am-241 & 1 to 0 pCi/ml Pu-239) over 100-year period.

- Select these arrow buttons to view and enter information for remaining constituents

- This is one of the more data-intensive models – these tabs each have multiple pages of entries.

- It pays to start with the Pathways tab first.
- Turn on the pathways that are of interest.

- ...for example, selecting the Agricultural tab reveals two additional layers of parameter input interfaces.  Accept or change values as appropriate.

- Accept or change values as appropriate.

## The GENII Intake Module (not yet compatible with FRAMES 2) offers choice of age groups and many inputs.  Most intakes are defined with a daily intake and the associated number of days/year.

- Make selections for GENII Health Impacts using ICRP 30/48.  Notice that each of the dose/risk options has additional associated method parameters to select.

- Make selections for MEPAS Health Impacts using ICRP dose and risk factors under the Radionuclide tab.

- When all lights in the local space are yellow, run each module in sequence.
- When all lights are green, intermediate and final results can be viewed by right clicking on any module icon and selecting View/Print Module Output.

## Questions?