Natural attenuation of explosives in soil and water systems at Department of Defense sites : final report
Pennington, Judith C.; Miyares, Paul H.; Ringelberg, David B.; Zakikhani, Mansour, 1954-; Reynolds, Charles M. (Charles Michael), 1950-; Felt, Deborah R.; Coffin, Richard B.; Cifuentes, Luis.; Gunnison, Douglas.; Fredrickson, Herbert L.; Jenkins, Thomas F.
Technical ReportAbstract: This report, which is a follow-on to the report “Natural Attenuation of Explosives in Groundwater at DoD Sites: Interim Report," presents results of a study to evaluate the feasibility of using stable isotopes of carbon and nitrogen in soil or groundwater to monitor natural attenuation of explosives. The report also includes continuation results from two research areas, toxicity testing of surface soils at the demonstration site and integration of biomarker data into the model 3DFATMIC (3-Dimensional Subsurface Flow, Fate, and Transport of Microbes and Chemicals). Results of stable isotope studies indicated that changes in carbon isotope ratios were too small to detect. Therefore, this approach is not feasible. However, changes in nitrogen ratios in TNT found in groundwater were detected across the contaminant plume. Once the rate and magnitude of these changes are related quantitatively to TNT attenuation rates, this approach may be feasible for monitoring attenuation processes. In toxicity tests, the significant negative correlation between TNT concentration and viable biomass in aquifer soils at the Louisiana Army Ammunition Plant, Doyline, LA, could not be related to toxicity of TNT to the indigenous microflora. In the modeling research area, the 3DFATMIC model exhibited a problem in the numerical code, and the amount of biomass data proved too small. Predictive simulations may be possible with the model once the code is revised and additional biomass data become available.
Environmental Laboratory (U.S.)Engineer Research and Development Center (U.S.)
Biomarkers; Stable isotopes; Toxicology; Toxicity; Explosives; 3DFATMIC; Groundwater modeling; Groundwater models; Groundwater pollution; Soil pollution; Soil remediation; TNT
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