Modeling Transport of Selected Organic Trace Pollutants during Riverbank Filtration Conditions

摘要

Riverbank filtration (RBF) is a widely used method of pre-treating surfacewater. In RBF, aquifer sediments act as a natural filter removing various organic tracepollutants as river water recharges ground water.This project was designed to determine the removal capabilities of organic tracecontaminants at a full scale RBF site in Brighton, Colorado. One of the goals of theproject was to develop a contaminant transport model in conjunction with a hydrologicmodel of the site. In preparation for designing the transport component of the model,input parameters were estimated from laboratory column experiments in several scales,and verified using field data from the site. Breakthrough curves for various contaminants,including pharmaceutically active compounds and other contaminants of interest, wereobtained from the soil column experiments. A parameter-estimation program was usedto model the processes controlling the fate of selected contaminants. Relevantprocesses included sorption, biodegradation, and diffusion of contaminants into lowpermeabilityzones. Model parameters from column experiments were super-imposed onfield-scale flow paths to simulate the fate of organic trace pollutants during RBF.The contaminant transport model was then used as a tool to optimize the full-scale siteby the determination of additional well locations, pumping rates, and other sitespecifications. The applicability of the contaminant transport parameters to other RBFlocations was also evaluated.