Modeling soil pile bioremediation

A model is presented for the analysis of bioremediation applied to an ex situ soil pile. The approach is based on the remediation of a pile containing the contaminated soil, which has been excavated from its original location, placed atop a bottom liner system and encapsulated with an impermeable cover. The liner system contains and isolates the contaminated soil and provides process control ports for injecting or withdrawing liquids or gases. The model is designed to accommodate aerobic and/or anaerobic metabolism of two classes of organic contaminants for which metabolic rates are significantly different. The model is also designed to accommodate nutrient stimulation and/or toxic inhibition of aerobic or anaerobic metabolism of either class of organics. The model presented here, together with a domain flow model which provides the convective transport velocity vector field, is a self-contained package of analyzing soil pile bioremediation. However, the model is also one component of an ongoing effort to analyze sequential ex situ treatment processes. Ultimately, this will be used in conjunction with models analyzing soil vapor extraction, bioventing, soil leaching, etc. to determine an optimum sequence configuration and operating strategy for remediating complex soil contamination problems.