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RECORD NUMBER: 20 OF 210

OLS Field Name OLS Field Data
Main Title Aquatic Fate and Transport Modeling Techniques for Predicting Environmental Exposure to Organic Pesticides and Other Toxicants - A Comparative Study.
Author Mulkey, L. A. ; Ambrose, R. B. ; Barnwell, T. O. ;
CORP Author Environmental Research Lab., Athens, GA.
Year Published 1986
Report Number EPA/600/D-86/122;
Stock Number PB86-216991
Additional Subjects Pesticides ; Water pollution ; Rivers ; Mathematical models ; Risk ; Environmental impacts ; Steady state ; Sediments ; Interactions ; Sorption ; Oxidation ; Hydrolysis ; Path of pollutants
Holdings
Library Call Number Additional Info Location Last
Modified
Checkout
Status
NTIS  PB86-216991 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 06/21/1988
Collation 38p
Abstract
Exposure assessment enhanced by mathematical modeling has become an accepted technique for evaluating the environmental risk associated with the release of toxic substances into various environmental media. Mathematical models for analyzing the behavior of toxic substances in river systems range from simplified, plug-flow transport procedures to dynamic water and sediment routing procedures incorporating characterization of the physical, chemical, and biological processes that collectively determine the toxicant concentrations in time and space. Four levels of such models can be identified: (1) steady-state, constant flow; (2) plug flow, time-of-travel analytical solution; (3) quasi-dynamic routing incorporating simple sediment interaction with the bed; and (4) dynamic routing incorporating dynamic, process-oriented sediment interaction with the bed. In levels 1, 3, and 4, chemical exchange with the bed is handled as a linear dispersive interchange. In each of the four levels, sorption, volatility, hydrolysis, photolysis, oxidation, and bacterial degradation of organic toxicants are included. These four levels of models were compared by predicting pesticide fate and transport within the Yazoo River system using candidates from each level.