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17. Development of a Quantitative Framework for Evaluating Natural Attenuation of 1,1,1‐TCA, 1,1‐DCA, 1,1‐DCE, and 1,4‐Dioxane in Groundwater.

Author

Adamson, David T., Wilson, John T., Newell, Charles J., Strasert, Brian A., de Blanc, Phillip C., Freedman, David L., Lebrón, Carmen, and Danko, Anthony

Subjects
GROUNDWATER, ISOTOPIC fractionation, SOFTWARE development tools, NATUROPATHY, BIOGRAPHICAL films, GROUNDWATER purification, GROUNDWATER analysis
Abstract

A series of quantitative decision frameworks were developed to aid in the evaluation of Monitored Natural Attenuation (MNA) as a remedy for 1,4‐dioxane, chlorinated ethanes, and chlorinated ethenes. The end product is an updated version of BioPIC, a successful, existing decision framework for MNA of chlorinated ethenes. In evaluating MNA, the goal is to follow existing protocols but also incorporate more recent insights that have increased the potential viability of this technology for a wider number of contaminants. This includes data supporting the first line of evidence for MNA (decreasing concentration trends over time at appropriate sampling locations), as well as data that will serve as secondary and tertiary lines of evidence for MNA. For the BioPIC update, a similar lines of evidence approach was developed, using information from literature and project‐specific data to identify the relevant lines of evidence. As part of the update, a model for predicting contaminant trends over time and distance, including a method to estimate site‐specific biodegradation rate constants for chlorinated ethenes, chlorinated ethanes, and 1,4‐dioxane, has been included within BioPIC. The quantitative software tool provides step‐by‐step technical guidance for collecting and evaluating other lines of evidence, including data associated with targeted 14C assays, isotope fractionation, biomarkers for degradation, geochemical parameters, and co‐contaminant concentrations, to improve the MNA evaluation process. Article Impact Statement: This paper describes a new technical framework to help evaluate monitored natural attenuation as a remedy for an expanded set of compounds. [ABSTRACT FROM AUTHOR]

Published
2022
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26. Impact of mixtures of chlorinated aliphatic hydrocarbons on a high-rate, tetrachloroethene-dechlorinating enrichment culture

Author

Adamson, David T. and Parkin, Gene F.

Subjects
Chemical industry -- Research, Biological products industry -- Research, Environmental issues, Science and technology, University of Iowa -- Research
Abstract

Researchers from the University of Iowa examined the ability of tetrachloroethene-dechlorinating culture to function in the presence of carbon tetrachloride and trichloroethane.

Published
2000

39. Field Test of Enhanced Remedial Amendment Delivery Using a Shear-Thinning Fluid

Author

Truex, Michael J., primary, Vermeul, Vince R., additional, Adamson, David T., additional, Oostrom, Mart, additional, Zhong, Lirong, additional, Mackley, Rob D., additional, Fritz, Brad G., additional, Horner, Jake A., additional, Johnson, Tim C., additional, Thomle, Jonathan N., additional, Newcomer, Darrell R., additional, Johnson, Chris D., additional, Rysz, Michal, additional, Wietsma, Tom W., additional, and Newell, Charles J., additional

Published
2015
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43. New Cost-Effective Method for Long-Term Groundwater Monitoring Programs

Author

GSI ENVIRONMENTAL INC HOUSTON TX, Newell, Charles J, Adamson, David T, McHugh, Thomas E, Rysz, Michal W, GSI ENVIRONMENTAL INC HOUSTON TX, Newell, Charles J, Adamson, David T, McHugh, Thomas E, and Rysz, Michal W

Abstract

This project involved basic research on an alternative groundwater sampling approach--vapor-phase groundwater monitoring--that relies on a different set of physical processes and analytical instruments to provide the Department of Defense (DoD) with reliable and accurate long-term monitoring for volatile organic compounds (VOCs). The overall goal of this research project is to evaluate the utility of on-site vapor-phase analysis of samples from a groundwater monitoring well as an alternative to off-site analysis of groundwater samples. Current approaches for long-term groundwater monitoring programs rely on water sampling and analysis using traditional decades-old protocols that are time-consuming and costly. Complying with the requirements of these monitoring programs comprise a significant portion of life-cycle remediation costs the for Department of Defense (DoD). There is an opportunity to use existing vapor-phase based technologies as part of a new approach that generates monitoring data more rapidly at a lower overall cost.

Published
2013

44. Treatment of RDX and/or HMX Using Mulch Biowalls

Author

ENVIRONMENTAL SECURITY TECHNOLOGY CERTIFICATION PROGRAM OFFICE (DOD) ARLINGTON VA, Ahmad, Farrukh, Newell, Charles J., Adamson, David T., ENVIRONMENTAL SECURITY TECHNOLOGY CERTIFICATION PROGRAM OFFICE (DOD) ARLINGTON VA, Ahmad, Farrukh, Newell, Charles J., and Adamson, David T.

Abstract

Organic mulch is a complex carbon material that is typically populated with its own consortium of microorganisms. The organisms in mulch breakdown complex insoluble organics to soluble carbon, which can then be utilized by these and other microorganisms as an electron donor for treating contaminants via reductive pathways. Mulch has advantages over other electron donors: it is cheaply available, long-lasting, and is naturally present in the environment. Over the last decade, organic mulch permeable reactive barriers (PRB) or biowalls, have enjoyed increased public interest as a relatively cheap technology for addressing contaminated groundwater. The mulch PRB is a passive technology and consequently requires no aboveground injection system, thereby greatly reducing operating and maintenance costs. To date, biowalls have been installed to bioremediate groundwater contaminated with a variety of electrophilic compounds, including chlorinated solvents and inorganics such as nitrate and perchlorate. This field demonstration represents the first ever application of mulch PRBs for the treatment of explosives contamination in groundwater. Heterocyclic nitramines, such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro- 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), are energetic materials that commonly make up the bulk of modern explosive formulations. Because of their poor soil sorption properties and their relatively high solubilities compared to other energetic materials, these compounds have been found to contaminate groundwater at military facilities where explosive materials are manufactured, packaged, or handled. Although there is little data to establish their human toxicity at low concentrations, these compounds are generally regarded as possible human carcinogens due to their ability to cause adverse effects in a variety of different organisms, including hepatic tumors in mice. Hence, there is a need to implement remediation technologies to treat RDX an, The original document contains color images. Prepared in collaboration with GSI Environmental, Inc.

Published
2008

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