Select Projects

Fate and Transport of Emerging Contaminants:  Gathered, reviewed, and analyzed PFAS data to identify potential source locations, evaluate contaminant plume evolution, and estimate potential impact on surface water, groundwater, fish, sediment, soil, and public and private water supply systems for several cases.  Reviewed and analyzed regional and site-specific geology and hydrogeology information to better understand the potential fate and transport of certain PFAS chemicals.

Superfund Site Cost Allocation:  Analyzed past costs allegedly incurred at a Superfund site in New Jersey.  Analysis included the review of invoices, environmental reserve tables, and insurance settlement proceeds to summarize the net past environmental response and legal defense costs incurred for different time periods.

Contaminant Source Identification:  Reviewed reports and databases from US EPA and State Environmental/Ecology websites to investigate the historical use and potential sources of PCBs in different claimed waterbodies; assess PCB concentrations in water and sediment according to water body features; and identify upland PCB sites based on categories of release, discharger, user, and disposal.  The results served as guidance for identifying the actions that caused PCB discharges/or presence within the watersheds.

Contaminant Transport Modeling:  Performed groundwater flow and solute transport modeling in both unsaturated and saturated zones using Visual MODFLOW and HYDRUS to evaluate potential impact of sulfate, boron, and arsenic from multiple coal ash surface impoundments to groundwater.

Contaminant Fate and Transport Modeling:  Performed NAPL release and spreading numerical simulations under different scenarios using HSSM to assess NAPL lens sizes. The results were used to evaluate proposed cost allocation between oil and gas parties at a former refinery.

Contaminant Fate and Transport Analysis:  Analyzed hydrogeologic data and historical contaminant concentrations and downgradient mass flux to assess fate and transport of chlorinated solvents across a large industrial area.  Differences in plume chemistries were used to estimate the contributions from multiple sources, and help allocate both past and future study and remedy costs associated with this industrial area.

Soil Erosion Analysis:  Evaluated chemical concentrations in soils at the facility and in nearby river sediment to understand the likely sources of PCBs in site soils and the river sediments.  Performed runoff analysis to estimate the quantify of contaminants transport to river via stormwater.  The analyses played a critical role in discussions about our client’s liability in the river sediment remediation costs.

Forensic Analysis:  Performed forensic chemistry analysis of polycyclic aromatic hydrocarbons (PAHs) from a refinery into an industrial discharge canal.  The analysis can be used to allocate potential liability and remediation cost.

Principal Component Analysis:  Conducted statistical and principal component analysis using MATLAB codes for constituents of interest in soil and sediment, including PAHs, PCBs, metals, pesticides, and dioxins/furans, at an Manufactured Gas Plant (MGP) site.

Selected Publications

Tang, T; Arshadi, M; Miller, E; Abriola, L. Forthcoming. “Optimal sampling design for down-gradient flux averaged concentration prediction and uncertainty reduction.”

Tang, T; Arshadi, M; Miller, E; Abriola, L. 2018. “Optimal Sampling Design for Down-gradient Flux Averaged Concentration Prediction and Uncertainty Reduction.” Presented at the Interpore 10th Annual Meeting, New Orleans, LA, May 14-17.

Tang, T; Arshadi, M; Yang, L; Abriola, L; Cápiro, N; Christ J; Miller, E; Pennell, K. 2017. “Source Zone Characterization Methods and Tools Development; Sensitivity Analysis and Uncertainty Quantification.” Presented at the SERDP and ESTCP Symposium, Washington, DC, November 28.

Wu, J; Lu, L; Tang, T. 2011. “Bayesian analysis for uncertainty and risk in a groundwater numerical model’s predictions.” Hum. Ecol. Risk Assess. 17(6):1310-1331.

Tang, T; Wu, J; Yang, Y. 2011. “Analysis of the impact of aquifer heterogeneity simplification to groundwater numerical predictions.” J. Geotech. Eng. 158(4):34-42.