Recent Improvements to an Advanced Atmospheric Transport Modeling System

Conference · Mon Oct 24 04:00:00 EDT 2005

OSTI ID:881485

Buckley, R L; Hunter, C H

The Atmospheric Technologies Group (ATG) has developed an advanced atmospheric modeling capability using the Regional Atmospheric Modeling System (RAMS) and a stochastic Lagrangian particle dispersion model (LPDM) for operational use at the Savannah River Site (SRS). For local simulations concerning releases from the Central Savannah River Area (CSRA), RAMS is run in a nested grid configuration with horizontal grid spacing of 8 and 2 km for each grid, with 6-hr forecasts updated every 3 hours. An interface to allow for easy user access to LPDM had been generated, complete with post-processing results depicting surface concentration, deposition, and a variety of dose quantities. A prior weakness in this approach was that observations from the SRS tower network were only incorporated into the three-dimensional modeling effort during the initialization process. Thus, if the forecasted wind fields were in error, the resulting plume predictions would also be erroneous. To overcome this shortcoming, the procedure for generating RAMS wind fields and reading them into LPDM has been modified such that SRS wind measurements are blended with the predicted three-dimensional wind fields from RAMS using the Barnes technique. In particular, the horizontal components in RAMS are replaced with the observed values at a series of 8 towers that exist within the SRS boundary (covering {approx}300 km{sup 2}). Even though LPDM is currently configured to account only for radioactive releases, it was used in a recent chlorine gas release to generate plume concentrations based on unit releases from the site of a train accident in Graniteville, South Carolina. This information was useful to local responders as an indication of potential protective actions downwind of the release.

• Research Organization: Savannah River Site (SRS), Aiken, SC
• Sponsoring Organization: USDOE
• DOE Contract Number: AC09-96SR18500
• OSTI ID: 881485
• Report Number(s): WSRC-MS-2005-00633
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
54 ENVIRONMENTAL SCIENCES
CHLORINE
COMPUTERIZED SIMULATION
ENVIRONMENTAL TRANSPORT
FLOW MODELS
GAS SPILLS
LAGRANGIAN FUNCTION
PLUMES
RADIOACTIVE EFFLUENTS
SAVANNAH RIVER PLANT