Thomas J Phelan

• Doctor of Philosophy
• Professor at United States Air Force Academy

Environmental remediation of polluted sites in developing communities often faces difficulties due to the misalignment of project objectives with the needs and interests of local communities, establishment of unrealistic expectations for the outcome of the project, and failure to account for the available resources in the community itself. Remediat...

Pollution remediation decisions in developing communities are often made with limited technical data and stakeholder engagement. Local knowledge of contamination is oftentimes neglected, resulting in efforts that fail to align with community objectives. In this work, we propose a new approach for incorporating local knowledge on contamination into...

The importance of the air base and the physical infrastructure that it contains to the success of air operations is not a new concept. There is a general acknowledgment in the Air Force today that the air base itself is a “weapons system.” As former Secretary of the Air Force Dr. Heather Wilson stated with the release of the Infrastructure Investme...

In response to the COVID-19 pandemic, a group of engineering educators in the United States and Colombia designed and led a two-week virtual “field session” for engineering undergraduate students that aimed at achieving the same educational outcomes as those from the previous in-country field session. Our NSF PIRE funded Responsible Mining, Resilie...

Environmental risk mitigation strategies employed in developing communities to address mercury pollution from artisanal and small-scale gold mining (ASGM) have largely failed to meet community needs, resulting in their abandonment. In contrast, the water and wastewater treatment sector has gained more traction, introducing sustainable and community...

In developing countries, remediation projects are predominantly implemented in areas with imminent risks due to human exposure routes. Projects experience challenges due to funding constraints derived from the history of legacy pollution and informal livelihood occupations in addition to political and economic instability and weak regulatory struct...

In-situ bioremediation, a widely applied treatment technology for source zones contaminated with dense non-aqueous phase liquids (DNAPLs), has proven economical and reasonably efficient for long-term management of contaminated sites. Successful application of this remedial technology, however, requires an understanding of the complex interaction of...

Revised Bodies of Knowledge, constituent input, and student demand are motivating the incorporation of sustainability concepts in traditional engineering curricula. While a variety of methods are in development, ranging from introductory engineering courses to capstone experiences to graduate-level treatment, the addition of new topics in an alread...

The total trapping number (N(T)), quantifying the balance of gravitational, viscous, and capillaryforces acting on an entrapped dense nonaqueous phase liquid (DNAPL) droplet was originally developed as a criterion to predict the onset and extent of residual DNAPL mobilization in porous media. The ability of this approach to predict mobilization beh...

Traditional steady state experiments to measure constitutive relations governing two-phase (organic-aqueous) flow in the subsurface often extend over periods of weeks or months. Alternatively, one-step or multistep outflow (MSO) experiments can be combined with application of a multiphase flow simulator and an optimization algorithm to achieve a mo...

Reduced interfacial tension displacement of nonaqueous phase liquids (NAPLs) in the subsurface can be an efficient means of remediating contaminant source zones. Application of technologies based upon this principle, however, is problematic for NAPLs that are denser than water (DNAPLs) due to their tendency to sink further into the subsurface when...

Numerical simulations examine the migration, entrapment, and mass recovery behavior of DNAPLs in aquifer systems with coupled textural and wettability variations. Permeability fields of varying degrees of heterogeneity (i.e., differing σln(k)2) were generated with sequential Gaussian simulation, using geostatistical parameters derived from core gra...

Dissertation (Ph.D.)--University of Michigan.

An understanding of the transport behavior of dense non-aqueous phase organic liquids (DNAPLs) in the subsurface is a prerequisite for the accurate assessment of chemical exposures and the design of effective remediation strategies. Although a number of studies have investigated the effects of physical or chemical heterogeneity on the fate of DNAPL...

Alhough it is commonly assumed that subsurface soils are completely water-wet, variations in wettability are likely in the contaminated subsurface. Dense nonaqueous phase liquids (DNAPLs) have often been released as part of acidic or basic mixtures containing surface active compounds. These mixtures can render subsurface soils intermediate to organ...

This paper describes ongoing research at the University of Michigan designed to explore the influence of solid and organic phase composition on DNAPL migration, entrapment, and recovery from contaminated aquifers. A compositional multiphase modeling framework for the prediction of dense nonaqueous phase liquid transport is presented. This model is...

This work explores the dissolution behavior of residual tetrachloroethylene (PCE) in chemically heterogeneous soils. A numerical solute transport simulator, that incorporates rate-limited dissolution and desorption using linear driving force expressions, was developed and applied to analyze soil column dissolution data and to conduct numerical diss...