Model Prediction of Long-Term Reactive Core Mat Efficacy for Capping Contaminated Aquatic Sediments

Abstract

This paper describes the development and validation of a one-dimensional, large-strain consolidation-coupled contaminant transport model. The RCM-XPORT2 model uses the CS2 large-strain consolidation approach coupled with reactive advective/dispersive solute transport through a deforming saturated porous media, capped with a reactive sequestering geomaterial known as a reactive core mat (RCM). Validation of the model is presented by simulating consolidation-coupled contaminant transport experiments performed on naphthalene-spiked sediment from the Neponset River in Milton, Massachusetts. Finally, the paper presents a hypothetical case study of pre- and post-RCM application polychlorinated biphenyl (PCB) fate and transport in the Lower Neponset River using RCM-XPORT2 and U.S. EPA Water Quality Analysis Simulation Program surface water quality model. The Neponset River case study evaluates the long-term effect of sediment RCM capping on reducing the water column PCB concentration.