Dense nonaqueous phase liquids (DNAPLs) are liquid chemicals that are heavier than water and do not mix easily with it. Because they sink through soil and groundwater, they can become trapped deep underground and act as long-term sources of contamination. Common dense nonaqueous phase liquids include chlorinated solvents and coal tar, which have been widely used in industrial and commercial activities. Their movement underground is often complex, making contaminated sites difficult to investigate and clean up.
The Integrated DNAPL Site Characterization and Tools Selection (ISC-1, 2015) guidance brings together decades of research and practical experience to help improve how DNAPL-contaminated sites are investigated. It explains how to use an integrated site characterization approach to better understand contaminant distribution, geology, groundwater flow, and natural attenuation processes so that cleanup decisions are based on a more complete picture of site conditions. The guidance also includes best practices for setting objectives, monitoring progress, adapting cleanup strategies, and selecting characterization and remediation tools. It serves as a valuable resource for regulators, site managers, consultants, and other stakeholders working to improve dense nonaqueous phase liquid site investigations and cleanup efforts.
This guidance is designed to complement Integrated DNAPL Site Strategy (IDSS-1, 2011), which helps site managers develop an integrated strategy for managing DNAPL-contaminated sites.
Topic(s): Chlorinated Solvents, DNAPL, Groundwater, Groundwater Monitoring, Site Characterization, Water Quality
