Evaluation of Time-Varying Hydrology within the Training Range Environmental Evaluation and Characterization System (TREECS TM)

The Training Range Environmental Evaluation and Characterization System (TREECS ) uses average annual hydrologic conditions as inputs for multi-media fate and transport models. This simplification reduces model complexity and data input requirements while providing the capability to conduct long-term predictions of the fate of munitions constituents (MC) as well as other contaminants. TREECS was recently modified to allow the option of using time-varying (daily) hydrology for forcing input conditions. This report summarizes the results of testing this new feature. MC fate predictions with daily hydrology are compared with those using average annual hydrology. Results show that the use of average annual hydrology produces more conservative results (i.e., higher media concentrations) than using daily hydrology. A validation application for lead downstream of small arms firing ranges is also presented in this report. The daily hydrology feature will be most useful for applications involving short periods (year or less) to evaluate the effects of variable precipitation and flow on MC concentrations in streams.
The original document contains color images. Prepared in collaboration with Los Alamos Technical Associates, Inc., Los Alamos, NM.