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Updated: Jul 6, 2026
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Dissolved Solute Sampling Across an Oxic-Anoxic Soil-Water Interface Using Microdialysis Profilers
Published on: March 24, 2023
Dissolution, sorption, and kinetics involved in systems containing explosives, water, and soil
Steven L Larson1, W Andy Martin, B Lynn Escalon
1Environmental Laboratory, U.S. Army Engineer Research and Development Center, Waterways Experiment Station, 3909 Halls Ferry Road, Vicksburg, Mississippi 39180, USA.
Environmental Science & Technology
|March 8, 2008
Summary
Understanding how explosives like TNT and RDX bind to soil is key for environmental cleanup. This study shows soil type and microbial activity significantly impact explosive sorption and transformation, affecting bioremediation strategies.
Area of Science:
- Environmental Science
- Soil Science
- Chemical Engineering
Background:
- Military ranges and ammunition sites face contamination from explosives like 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX).
- Bioremediation efforts for these nitroaromatic compounds show variable success, potentially linked to unknown interactions between explosives and soil matrices.
- Effective environmental management requires understanding the fate and transport of these energetic materials.
Purpose of the Study:
- To investigate the dissolution and sorption properties of TNT and RDX in six distinct soil types.
- To elucidate how soil characteristics influence the binding of explosives.
- To inform the development of conceptual models for sequestration, risk assessment, and site evaluation.
Main Methods:
- Experimental analysis of crystalline TNT and RDX in three-way systems (explosive, soil, water).
- Comparison of sorption effects in sterile (gamma-irradiated) versus nonsterile soil conditions.
- Characterization of explosive solubility and transformation byproduct formation.
Main Results:
- Maximum explosive solubility was not achieved due to sorption onto soil particles.
- Formation of transformation byproducts was observed.
- Significant differences in sorption were noted between sterile and nonsterile soils, indicating microbial influence.
Conclusions:
- Explosive sorption to soil particles limits solubility and influences transformation processes.
- Soil type and microbial activity (sterility) play critical roles in the behavior of TNT and RDX in soil-water systems.
- Findings are crucial for refining bioremediation strategies and environmental risk assessments at contaminated sites.
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