Contaminant Storage and Release in Low Permeability Zones
SERDP 2014 Project-of-the-Year Award for Environmental Restoration
Dr. Tom Sale, Colorado State University
Basic Research Addressing Contaminants in Low Permeability Zones
(Initially Released December 8, 2014) Contaminants stored in low permeability zones can be a critical issue for treatment and management of source zones and contaminant plumes in groundwater. Contaminant storage in low permeability zones may occur through diffusion and/or slow advection of dissolved-phase contaminants over time. As these stored contaminants are subsequently released, they can serve as a long-term source, limiting the ability to achieve groundwater cleanup goals. A more comprehensive understanding of the basic process of contaminant storage in low permeability zones is essential to the development of assessment and management methods.
Dr. Tom Sale of Colorado State University and his team have developed analytical and numerical modeling techniques to address transport and fate of contaminants in heterogeneous media, along with a State-of-the-Science review of management of contaminants in low permeability zones in aquifers. Their modeling efforts suggest that matrix diffusion sources may be a larger contributor to overall source lifetime than DNAPL source zones. Building on previous research, the team is developing a decision framework that can help site managers determine if a site is dominated by DNAPL or matrix diffusion sources. An interactive Web-based version of the 14 Compartment Model, a conceptual framework for remediation decision making at contaminated sites, will be available both as an easily accessible internet version and as a downloadable version for more secure data management.
The team is also investigating cryogenic core collection and high-throughput core analysis as tools to achieve high-resolution characterization. The combination of these tools offers a more rapid, effective, and lower-cost method of site characterization, providing data necessary for restoration of sites impacted by chlorinated solvents and other persistent contaminants.
The results of this study have improved understanding of contaminant storage and release in low permeability zones. This understanding along with the accompanying guidance and tools can be used to evaluate the efficacy of current site management technologies and enhance site management decisions.
For this groundbreaking work, Dr. Sale and his project team received the 2014 SERDP Project-of-the-Year Award for Environmental Restoration. Project Overview
- Dr. Tom Sale, Colorado State University
- Dr. Charles Newell, GSI Environmental Inc.
- Dr. Beth Parker, University of Guelph, Canada
- Dr. J.F. Devlin, University of Kansas
- Steven Chapman, M.Sc., P.Eng., University of Guelph, Canada
- Dr. Kevin Saller, TSU - CDM Smith
- Dr. David Adamson, GSI Environmental Inc.