Luther Brown

The goal of the Luther’s PhD project is to develop methodologies for the design of reliable, efficient and cost-effective pump and treat (PAT) remediation systems that leverage the effects of natural attenuation (NA). NA occurs at most contaminated sites, but its intensity depends on the types and concentration of contaminants, as well as the physical, chemical, and biological site characteristics. NA supports contaminant degradation by processes such as aerobic respiration, methanogenesis and fermentation. This research stems from the hypothesis that NA can be used to greatly enhance the planning of PAT strategies. This is however a challenge because of the uncertainty of site-specific conditions. Groundwater models which incorporate biodegradation processes will be created and used to maximize contaminant removal. Optimization algorithms will be combined with groundwater models to identify the most effective pumping strategies, as well as the most cost-effective outcomes. Supplementary in-situ treatment strategies to complement the PAT system will also be considered, such as the addition of permeable reactive barriers, oxygen release compounds, microbial fuel cells, air sparging, water injection (to facilitate mixing), and other interventions.

Aspects of uncertainty in the system behaviour will also be included in the overall design process. The outputs will be (i) a definition of PAT design objectives and constraints, with considerations on model and parameter uncertainty, overall cost, remediation time, contaminant removal, and risk to potential contaminant receptors, and (ii) application to the selected study site and comparison with current remediation strategy in relation to remediation cost, reliability, and effectiveness.