Summary Of Identification Of Rrgulatory Acceptability Of Enhanced Attenuation Categories

Résumé du livre

Chlorinated solvents once introduced to the subsurface are a persistent contaminant. Though many types of active treatments have been developed and deployed to treat contaminated sites, most sites will ultimately incorporate the use of passive treatments into the remediation process. A process favored by many is the use of Monitored Natural Attenuation that relies on the natural attenuation processes occurring within the system to remediate the contaminants. However, it is likely there will be instances where the natural attenuation processes will be insufficient to reduce the level of contamination to acceptable levels in an acceptable span of time. Rather than redeploying source treatments, the Department of Energy along with the Interstate Technology and Regulatory Council (ITRC) are developing the concept of Enhanced Attenuation (EA). An enhancement is any type of intervention that might be implemented in a source-plume system that increases the magnitude of attenuation by natural processes beyond that which occurs without intervention. Enhanced Attenuation is the result of applying an enhancement or intervention technique that will sustainably manipulate a natural attenuation process leading to an increased reduction in mass flux of contaminants. Efforts are moving forward along several fronts in developing this concept. This effort is a follow-on to initial discussions with site owners, regulators and stakeholder organizations in the development of the concepts of Enhanced Attenuation, the use of mass balance to evaluate the stability of a waste site/groundwater plume, and identification of tools that will support characterization and monitoring efforts for MNA and EA treatments. Those discussions are documented in the report titled ''Summary Document of Workshops for Hanford, Oak Ridge and Savannah River Site as part of the Monitored Natural Attenuation and Enhanced Passive Remediation for Chlorinated Solvents-DOE Alternative Project for Technology Acceleration'' (WSRC, 2003). The objective of this report is to document the May 12th, 2005 deliberations of the ITRC Enhanced Attenuation: Chlorinated Organics team. The purpose of these deliberations was to identify issues related to regulatory acceptability of the different categories of processes/technologies that may be considered enhancements.