You are here:
GENERAL METHODS FOR REMEDIAL PERFORMANCE EVALUATIONS
Citation:
RSKERL. GENERAL METHODS FOR REMEDIAL PERFORMANCE EVALUATIONS. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/R-92/002 (NTIS 92-166842), 1992.
Impact/Purpose:
Information.
Description:
This document was developed by an EPA-funded project to explain technical considerations and principles necessary to evaluated the performance of ground-water contamination remediations at hazardous waste sites. This is neither a "cookbook", nor an encyclopedia of recommended field, laboratory, and data interpretation methods. Rather, this report presents and discusses suggested generic principles for formulating site-specific performance evaluation strategies for ground-water contamination remediations. It is widely accepted that ground-water contamination problems cannot be adequately defined or addressed until the governing physical, chemical, and biological processes which affect the fate and transport of contaminant are characterized in detail. Recent research has led to a better understanding of these complex processes and how they control the movement of contaminated ground water through the subsurface. This research has demonstrated the pump-and-treat remediations are far more complicated than previously thought. Many of the complications result from the tortuosity of the ground-water flowlines that are generated by the remediation wellfield and the re-distribution of contaminant concentrations at local monitoring wells may no longer be useful for predictions and evaluations regarding the growth or reduction of the contaminant plume. Further, the pattern of flow velocities and directions that resulted from the remediation wellfield may change substantially over time, thus complicating attempts to evaluate the progress of the pump-and-treat remediation. The optimal effectiveness (extent and uniformity of cleansing) and efficiency (minimization of costs and duration) of a remediation can often be obtained by managing the pump-and-treat system in terms of flowrates and extraction locations in response to reduction in contaminant mass in portions of the plume. Active management of this kind must be supported by the continuous gathering of key site characterization data.