Technical Protocol for Evaluating Natural Attenuation of Chlorinated Solvents in Ground Water
This protocol provides guidance for environmental managers on the steps that must be taken to understand the rate and extent to which natural processes are reducing contaminant concentrations at sites that are contaminated by chlorinated solvents. The document identifies parameters that are useful in the evaluation of natural attenuation of chlorinated solvents (chlorinated aliphatic hydrocarbons and/or fuel hydrocarbons) and provides recommendations to analyze and interpret the data collected from the site characterization process. It also provides suggestions for integrating monitored natural attenuation (MNA) into an integrated approach to remediation that also includes an active remedy. It includes a useful list of definitions of terms related to the topic. It is a technical, not a policy, document. Data gathered using this protocol can be used to evaluate whether MNA by itself or in conjunction with other technologies is sufficient to achieve site remedial objectives, and to compare the relative effectiveness of MNA and other remedial methods. This protocol is the result of a collaborative field and laboratory research effort involving researchers from EPA's Office of Research and Development, the U.S. Air Force, and the U.S. Geological Survey.