Development and application of a methodology to evaluate natural attenuation of chlorinated solvents using conceptual and numerical models

Natural attenuation of chlorinated solvents has being increasingly used by engineers and regulators as a remedial alternative to contaminated aquifers because the numerous advantages it has over more traditional engineered solutions. However, natural attenuation has been clearly demonstrated only for a selected class of organic compounds, primarily fuel hydrocarbons. The scientific community has recognized that the surge in use of natural attenuation has outpaced certain guidelines that have been developed for its application. This study evaluates a novel approach to evaluate natural attenuation of chlorinated solvents by using models incorporating important physical and biogeochemical processes that can be critical for a successful evaluation of natural attenuation.; A hydraulic characterization methodology was developed to estimate parameters that influence the transport of solutes in groundwater environments. Biogeochemical data coupled with historical development of the VOC plume were used to develop a conceptual model for the contaminated site. This model was translated into a numerical model incorporating the compiled information and two snapshots of the plume historical development were successfully validated.; The successful application of the methodology developed in this dissertation could become the foundation for the development of a series of guidelines to evaluate natural attenuation of chlorinated solvents.