Pollutant mixtures – particularly byproducts of the incomplete combustion of fossil fuels and other anthropogenic sources – abound in the environment. Despite their prevalence, we know little about how many pollutant mixtures behave, both in the laboratory and in situ, and therefore how they transport within the environment. Thermodynamic and kinetics characterization of energy generation byproducts and environmental media contaminated by pollutant mixtures provides data necessary for policy makers and environmentalists alike to reach a consensus on the risks posed by various fuel sources and to improve transport modeling and remediation strategies. The sequestration, bioavailability, degradation and remediation of these pollutant mixtures form another line of research. Investigations include waste-to-byproduct conversions of unconventional fuel refuse as carbon sorbents, as well as seeking to understand the mechanisms by which pollutant mixtures bind to sorbents. We question why pollutant mixtures behave differently than the sum of their pure compound constituents, and whether modeling contaminant mixtures as a single component jeopardizes the accuracy and reliability of fate and transport models.