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GENII-NESHAPS
Risk Assessment
The GENII System provides a state-of-the-art, fully documented set of software for calculating radiation dose and risk from radionuclides released to the environment. The GENII-NESHAPS Edition is specifically designed to help site managers plan and improve compliance with 40 CFR 61, Subparts H and I.
On this page:
- Download Software, Instructions, and Documentation
- Background
- Regulatory Context
- Application Niche
- Strength and Limitations
- Hardware Requirements
- References
Download Software, Instructions, and Documentation
| File | Size | Format |
|---|---|---|
| GENII-NESHAPS Model, Version 2.0 | 26.1Mb | [about zip format] |
| Getting Started with GENII Version 2 NESHAPS Edition | 499 Kb | [about pdf format] |
| GENII-NESHAPS Version 2.0 Users’ Guide | 1.3 Mb |
[about pdf format] (best viewed with Acrobat Reader version 7.05 or higher) |
| GENII-NESHAPS Version 2.0 Software Design Document | 880 Kb | [about pdf format] |
Background
The U.S. Department of Energy released GENII Version 1.0 in 1988. The U.S. Environmental Protection Agency developed a new version of the software in 2002, GENII Version 2.0, incorporating improved transport models, exposure options, dose and risk estimation, and user interfaces.
In 2002, a new edition, GENII-NESHAPS, was developed specifically for demonstrating compliance with the dose limits specified in 40 CFR 61.93(a), the National Emission Standards for Hazardous Air Pollutants for radionuclides. In 2003, the software was peer reviewed.
Both editions of the GENII Version 2.0 software system can be downloaded:
THe GENII-NESHAPS edition offers limited capability to change parameters, but the advantage is that it automatically incorporates specific requirements of the NESHAPS regulation. The original GENII edition allows you to change specific parameters. Both GENII and GENII-NESHAPS have been reviewed and tested extensively.
Regulatory Context
GENII-NESHAPS is designed specifically for demonstrating compliance with the National Emission Standards for Hazardous Air Pollutants in 40 CFR 61, Subparts I and H. EPA plans to approve the model for this purpose through a rulemaking beginning in 2006.
Application Niche
GENII-NESHAPS incorporates the internal dosimetry models recommended by the International Commission on Radiological Protection in ICRP 56-72 and the radiological risk estimating procedures of Federal Guidance Report 13 into updated versions of existing environmental pathway analysis models. The software was designed with the flexibility to accommodate input parameters for a wide variety of generic sites. GENII-NESHAPS functions within the Framework for Risk Analysis in Multimedia Environmental Systems (FRAMES), which allows GENII to run in conjunction with and provide inputs to related software.
Strengths and Limitations
Models
GENII-NESHAPS includes the dosimetric models of ICRP
Publications 56 through 72, and the related risk factors
published in Federal
Guidance Report 13. These dosimetry and risk
models are considered to be state of the art by
the international radiation protection community
and have been adopted by most national and international
organizations as their standard dosimetry methodology.
Dose Calculations
The GENII-NESHAPS system calculates radiation
doses from chronic atmospheric releases. Air transport
calculations use a chronic (annual average) plume model,
which allows use of an effective stack height or calculation
of plume rise from buoyant or momentum effects (or both).
Risk Estimates
The system calculates health risks to individuals or populations
by applying appropriate risk factors to either
the effective dose, the effective dose equivalent, or the organ
dose. It also estimates cancer risk to specific organs or tissues
using risk factors from Federal
Guidance Report 13.
Data
Entry, Use, and Available Parameters
GENII-NESHAPS offers interactive,
menu-driven user interfaces for entering
data. It provides default exposure and consumption parameters
for the maximally exposed individual.
It accepts radionuclide source term information
in formats appropriate for different exposure scenarios --as
release quantities where transport is involved or as concentrations
in environmental media (air, water, soil) in
the absence of transport. The model also considers decay of
parent radionuclides and in-growth of radioactive decay products
prior to the start of the exposure scenario for either basic
or derived concentrations. Because the system works sequentially
on individual decay chains, unlimited numbers of radionuclides,
including the source term and accumulated decay
products, can be processed in a single run.
Exposure Pathways
The radial grid used in GENII-NESHAPS allows
consideration of both the distance and direction to target
individuals and populations. The model accommodates scenarios
involving chronic releases to air from ground level
and/or elevated sources.
Exposure pathways include direct exposure from surface
sources (soil) and air (semi-infinite cloud and finite
cloud geometries) as well as inhalation and ingestion.
The tritium model includes consideration of both gas and
vapor, conversion of gas into vapor, and biological conversion
of both into organically-bound tritium.
Hardware Requirements
- Windows 2000 or XP
- Minimum disk storage of 80 megabytes; >100 megabytes recommended
- Processor speed >1 gigahertz recommended
References
Napier, B.A., R.A. Peloquin, D.L. Strenge, and J.V. Ramsdell. 1988. GENII-The Hanford Environmental Radiation Software System , PNL-6584, Volume 1: Conceptual Representation, Volume 2: Users’ Manual, Volume 3: Code Maintenance Manual. Pacific Northwest Laboratory, Richland , WA .
Napier, B.A. 2005. Getting Started with GENII Version 2 NESHAPS Edition . PNNL-14993, Pacific Northwest National Laboratory, Richland , WA .
Napier, B.A., D.L. Strenge, J.V. Ramsdell, Jr., P.W. Eslinger, and C.J. Fosmire. 2005.GENII NESHAPS Software Design Document . PNNL-14584, Pacific Northwest National Laboratory, Richland , WA .
Napier, B.A., 2005. GENII NESHAPS Users’ Guide . PNNL-14583, Pacific Northwest National Laboratory, Richland , WA .
