Natural Attenuation of Explosives in Groundwater
Abstract
Monitored natural attenuation (MNA) is a remedial alternative for explosives contaminated groundwater at sites where a decline in contaminant mass can be demonstrated to occur at a rate sufficient to ensure the protection of potential receptors. MNA is not a no action alternative, but requires careful characterization of the site hydrogeology and contaminant distribution, long-term monitoring of groundwater, and groundwater modeling to conceptualize the contaminant plume and to predict future migration and attenuation. MNA in the context of the demonstration described here does not include intervention to promote natural processes. Demonstrating that MNA is a viable remedial alternative requires gathering a weight of evidence that natural processes are sufficient to protect receptors of concern within a reasonable time-frame. Explosives are subject to several attenuation mechanisms that effectively reduce concentrations in natural systems. Some of these processes have been defined, while other are poorly understood. MNA relies upon quality site characterization data, carefully conducted long-term monitoring, and groundwater modeling for contaminant conceptualization and long-term predictions of contaminant fate. Determining attenuation rates for explosives requires demonstration of declining mass over time, and conservative extrapolation of attenuation capacity and microbial degradation potential from the laboratory to the field. This demonstration was designed to define and optimize the data collection and processing procedures for evaluation, selection, and implementation of MNA for explosives. The demonstration was conducted at a former waste disposal lagoon site at the Louisiana Army Ammunition Plant, Minden, LA. Thirty wells were monitored quarterly over a two-year period.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1999
- Accession Number
- ADA607329
Entities
People
- Judith C. Pennington
Organizations
- Engineer Research and Development Center