Current Projects

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BPC-GCLs are desirable because, compared to traditional bentonite GCLs, they offer a greater resistance to certain aggressive (e.g., high or low pH, high ionic strength) leachates that are produced by industrial and mining waste streams. The objective of this research is to accelerate the aging of BPC-GCLs in the laboratory environment in order to predict their service life under different conditions including leachate chemistry and waste temperature. This research will provide insight into how the polymer component elutes or degrades over time, and how this will affect the long-term hydraulic conductivity of the BPC-GCL.

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Coal combustion products (CCPs) are residues resulting from the incomplete combustion of pulverized coal at coal fired power plants and can vary in both chemical and physical structure depending on the coal type and combustion method utilized. CCPs are known to contain hazardous constituents with the potential to impact groundwater quality if leachate quantity and concentration is high. It is imperative that we are familiar with leachate flow patterns and hydraulic properties that each CCP type exhibits to safely dispose of the waste products correctly. The goals of this research are to create site-specific models anticipating quantities of leachate produced through different waste management scenarios, and to catalog the specific hydraulic properties of CCP types. This is a collective research effort between University of Virginia and Vanderbilt University.

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PFAS have been incorporated into many different consumer and industrial uses since the 1940’s for their useful surfactant properties such as hydro- and lipophobicity.  They have been identified as an emerging contaminant with few degradation pathways and many potential routes of human exposure and toxicity. Given the high volume of waste containing PFAS, there is interest in learning more about the fate of leachates containing PFAS. The objective of this research is to look into the fate of PFAS-containing leachates in environmental containment systems in a laboratory setting in order to document their transportation and ability to permeate through containment liners.  This research will provide insight into the relatively unknown mass cycle of PFAS in the waste stream.

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In landfills, the decomposition of organic materials prior to, during, and after disposal is a natural process that produces odors that can be objectionable. Minimizing and managing odors has become a persistent and pervasive challenge in the solid waste industry. The issue has become more poignant in recent years as land development adjacent to landfills and other solid waste management facilities has increased. The primary objective of this research is to compile information that summarizes the extent of the issue, best management practices, available products/technologies and assess their relative merits.

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Disposal facilities for low-level radioactive waste (LLW) and mixed waste (MW) have leachate containing long-lived radionuclides, such as iodine-129 (129I) and technetium-99 (99Tc). Theses radionuclides exist predominantly in an anionic speciation (e.g., 129I- and 99TcO4-), are highly mobile in the environment, and have a very long half-life (over a million years). A multisorbing barrier (MSB) material is being developed for LLW and MW facilities that can bind anionic radionuclides as well as a variety of other constituents of concern (e.g. cationic species, organic compounds, and mercury) while also maintaining very low hydraulic conductivity. MSB is comprised of a combination of materials that have complementary sorption characteristics, such as sodium bentonite clay (NaB), organoclay (OC), and anion resins (R).