Past experience has shown that groundwater remediation can successfully achieve final cleanup goals at most sites, but highly complex sites are more challenging. The Interstate Technology and Regulatory Council (ITRC) addresses this issue in a document entitled "Using Remediation Risk Management to Address Groundwater Cleanup Challenges at Complex Sites." The ITRC document applies the framework of project risk management for site remediation to identify and manage groundwater remediation challenges at complex sites.
Remediation Risk Management
In the remediation risk management (RRM) process, project risks that may occur during site remediation are identified in an effort to better achieve secondary objectives of remediation (i.e., efficiency, schedule and cost effectiveness), while supporting the primary objective of remediation (i.e., protection of human health and the environment). ITRC provides a detailed discussion of the RRM process in its publication entitled "Project Risk Management for Site Remediation," which is available via the Internet at http://www.itrcweb.org/ GuidanceDocuments/RRM-Lpdf.
The ITRC document is intended to inform state regulators, practitioners, and other stakeholders who are evaluating technical cleanup challenges within their own programs. It identifies and evaluates several key technical challenges for groundwater remediation at highly complex sites. As part of the mitigation measures for project risks associated with those technical challenges, the document also describes several long-term management designations and approaches used at complex sites to protect human health and the environment over long time frames. These long-term management designations and approaches are typically one part of an overall site-specific remedial strategy that complies with existing regulations. Examples include use of technical impracticability waivers, greater risk waivers, state designations for groundwater management zones, and site management using a phased approach. Use of these designations at highly complex sites is demonstrated through case studies.
RRM for Groundwater Remediation
When applied to groundwater cleanup activities at highly complex sites, the RRM process is designed to help project managers:
* Identify key technical challenges;
* Evaluate the likelihood and impact of these challenges on the remedial strategy; and
* Mitigate these challenges through better design, evaluation, and operation of groundwater treatment and management systems.
Groundwater remediation typically involves the following steps: 1) source removal and reduction, 2) plume treatment to reduce the size and extent of contamination, 3) plume containment to limit the extent of contamination, and 4) monitoring and/or institutional controls. Both traditional and innovative remediation technologies are used for groundwater cleanup. However, a small percentage of environmental remediation sites are highly complex, and it may not be practicable to restore the entire groundwater plume to beneficial uses at these sites within a reasonable time frame.
Regulatory programs specify the process for selecting a remedy. For example, remedy selection for CERCLA sites is guided by nine criteria, and similar corrective measure evaluation criteria have been established for RCRA sites. The RRM process does not replace these criteria, or any other program requirements, for remediation selection. Instead, it is meant to improve remedial decision making by identifying project risks, and then considering those risks during remedy selection and implementation. The RRM process helps the...