The air, land, water analysis system (ALWAS): Multi‐media pathways of organic pollutants in freshwater systems

Abstract

The Air Land Water Analysis System (ALWAS) is a multi‐media environmental model for describing the atmospheric dispersion of toxicants, the surface runoff of deposited toxicants, and the subsequent fate of these materials in surface water bodies. ALWAS depicts the spatial and temporal distribution of contaminant concentrations in a watershed and the air above it. Linked in ALWAS are three submodels that provide for independent and partially coupled usage modes Dispersion and Deposition of Toxics (DiDOT); a modification, called NPSDEP, of the Non‐point Source Model; and Exposure Analysis Modeling System (EXAMS).

ALWAS’ structure, scope and limitations, features, and inputs and outputs are described.

The results of a hypothetical test simulation, including sensitivity analysis, are presented.

Key words:

• Exposure Assessment
• Mathematical Model
• Multi‐media Model
• Toxic Substances