Chemical enhancements to pump-and-treat remediation. Ground-water issue

Conventional pump-and-treat technologies are among the most widely used systems for the remediation of contaminated ground-water. Within recent years it has become recognized that these systems can require protracted periods of time to make significant reductions in the quantity of contaminants associated with both the liquid and solid phases which constitute the subsurface matrix. Evaluating the effectiveness of pump-and-treat remediations at Superfund sites, as well as attempting to improve this effectiveness, are issues identified by the Regional Superfund Ground Water Forum as a concern of Superfund decision makers. The Forum is a group of ground-water scientists and engineers, representing EPA's Regional Superfund Offices, organized to exchange the most recent information related to ground-water remediation at Superfund sites. Recent research has led to a better understanding of the processes involved in the transport and transformation of contaminants in the subsurface. While some of these processes are not readily amenable to enhance removal by ground-water extraction, others suggest that there are available techniques to increase the efficiency of these types of remediation systems. The intent of the document is to explore the use of chemical enhancement to improve ground-water remediation efficiencies using pump-and-treat technologies, and point out arenas of contamination where suchmore » techniques are not practical.« less