Topical Lime Treatment for Containment of Source Zone Energetics Contamination
Abstract
Energetic compounds, such as 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and their degradation products can act as a source of contamination for soil on Department of Defense testing and training ranges. Base hydrolysis degrades nitroaromatics and nitramines, and the potential effectiveness of lime to induce this reaction has been demonstrated at the laboratory scale. The objective of this research was to further examine both basic and applied aspects of alkaline application as an inexpensive and effective means of reducing source-zone contamination on military ranges. Bench-scale microcosms were used to examine basic conditions that could affect the alkaline hydrolysis reaction, such as soil organic matter content, lime concentration, soil type, and contamination type. Results from experiments using soil from a variety of ammunition production facilities and training ranges, in general, support the use of explosive contaminant treatment by alkaline material in well-mixed systems. RDX in crystalline form was more resistant to treatment, possibly due to limitations associated with the dissolution of the RDX from the crystal to the aqueous phase. Larger-scale experiments, conducted in vessels packed with approximately 55 kg of soil, were used to investigate topical versus well-mixed applications of three alkaline materials (hydrated lime, quicklime, and Class C fly ash). TNT, RDX, and HMX in the mixed system were removed quickly from both the leachate and soil. However, results from experiments with topical applications of alkali material indicated that the aqueous transport of hydroxide ion was not sufficient to overcome the buffering capacity of the soil. Consequently, the soil pH was not raised to the extent necessary for alkaline treatment of explosive compounds. This result is fundamentally related to the CEC properties of the soil and is consequently considered a soil specific (and therefore site specific) result.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2003
- Accession Number
- ADA417946
Entities
People
- Catherine C. Nestler
- Deborah R. Felt
- Jeffrey L. Davis
- Michael C. Brooks
- Steven L. Larson
Organizations
- Engineer Research and Development Center