Enhanced Attenuation: Chlorinated Organics

About the Resource:

The team monitored remedial activities nationwide, documenting the use and importance of EA as a site management tool. EA is a site management tool that provides a decision-making framework and incorporates a “bridge” between MNA and remedial technologies. Three important features of EA are:

  1. The evaluation of mass balance, defined as the relationship between mass loading and attenuation capacity of an aquifer
  2. A decision framework that provides guidance for site decisions
  3. A “toolbox” of potential EA technologies, known as “enhancements.”

One of the most important products of the team is the decision flowchart, which provides a clear and concise pathway so that regulators and others have guidance for the evaluation of the overall site conceptual model and the incorporation of a phased approach for site rehabilitation.

Team Background:

While remedial strategies were being used in combination with monitored natural attenuation (MNA), there was no guidance or “process” available regarding when or how to implement these strategies at contaminated chlorinated organic sites. The ITRC Enhanced Attenuation: Chlorinated Organics (EACO) Team developed a decision-making framework that not only defines the enhanced attenuation (EA) concept but also incorporates a well-defined process as a site management tool. The EACO Team and the DOE MNA/EA for Chlorinated Solvents project team formed a partnership in 2004. The team also included members from five state regulatory agencies; industry; federal agencies, including the Department of Energy and Environmental Protection Agency; academia; and stakeholders.