Impacts of Sorption on In Situ Bioremediation of Explosives-Contaminated Soils.
Abstract
Bioavailability of contaminants in soils may depend upon the concentration of the contaminant in the solution phase, which is dependent upon the ease with which the contaminant moves from fixed states into the solution phase. When bioremediation is the goal, enhancement of bioavailability by increasing solution phase concentrations of the contaminant may be necessary. Objectives of this study were to characterize desorption of ThT, RDX, and HMX in soils and to enhance solution phase concentrations by using surfactant and hot water. Desorption kinetics and isotherms were determined on four explosives contaminated soils using shake tests. Isotherms were determined for aqueous, surfactant, and hot water challenges. Column leaching experiments were performed using one of these soil and aqueous challenge over a period of 35 days. Results indicated that soil concentration of explosives exerts an important impact upon solution phase availability. When explosive concentrations in soils were sufficiently high to produce free product in the soil, solubilization was the dominant mass transfer process. When concentrations were low, desorption, convection, and dispersion controlled solution phase concentrations. Surfactants generally increased solution phase concentrations of explosives; however, effectiveness was less dramatic in soils having limited explosives concentration. Hot water also increased solution phase concentrations, but was not as effective as surfactants.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1995
- Accession Number
- ADA294439
Entities
People
- Judith C. Pennington
- Tommy E. Meyers
- Trudy J. Olin
- William M. Davis