Exact Analytical Solutions for Contaminant Transport in Rivers

Abstract

Contaminant transport processes in streams, rivers, and other surface water bodies can be analyzed or predicted using the advection-dispersion equation and related transport models. In part 1 of this two-part series we presented a large number of one-and multi-dimensional analytical solutions of the standard equilibrium advection-dispersion equation (ADE) with and without terms accounting for zero-order production and first-order decay. The solutions are extended in the current part 2 to advective-dispersive transport with simultaneous first-order mass exchange between the stream or river and zones with dead water (transient storage models), and to problems involving longitudinal advectivedispersive transport with simultaneous diffusion in fluvial sediments or near-stream subsurface regions comprising a hyporheic zone. Part 2 also provides solutions for one-dimensional advective-dispersive transport of contaminants subject to consecutive decay chain reactions.

Point dilution tests to calculate groundwater velocity: an example in a porous aquifer in northeast Italy

“…Even though CXTFIT was derived for porous media transport problems, the code is also applicable to most of the problems concerning surface water (van Genuchten et al 2013b). In this example, the apparent velocity (v a ), which acts inside the piezometers (Fig.…”

The Potential of Isotopic Tracers for Precise and Environmentally Clean Stream Discharge Measurements

“…They are known to be mainly advective but can be controlled by diffusion in the presence of fine streambed sediments, such as clays, in calm streams [15]. Hyporheic exchanges are typically modelled using the classical advection dispersion equation (ADE) to which a sink term representing the subsurface exchanges with the stream is added [15,[17][18][19][20]. Then, hyporheic flow represents the portion of stream water that is transported through the hyporheic zone before returning to the stream.…”

حل تحلیلی معادله‌ی انتقال آلودگی به‌ازاء فعالیت چندین منبع آلاینده‌ی نقطه‌یی با الگوهای زمانی دلخواه در حالات ۱ و ۲ بعدی با استفاده از روش تابع گرین

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