A Systematic Approach for Designing and Operating DGR™ Systems to Advance Plume Restoration

Dynamic Groundwater Recirculation or DGR™ is an innovative remedial strategy that significantly advances conventional pump and treat (P&T) designs of the past. Rather than simply hydraulically contain the groundwater plume, which is often the objective of a traditional P&T system, a DGR™ system creates dynamic groundwater flow conditions that serve to boost the natural flushing processes occurring within an impacted aquifer. Because the underlying concept of a DGR™ system is relatively simple— accelerate the influx of clean groundwater to promote aquifer flushing by driving contaminant mass out of the aquifer (both flow and storage zones) via enhanced advection and diffusion—DGR™ can be a highly effective remedial technology particularly when applied to sites with soluble contaminants, complex geology, and/or large diffuse plumes. To date, DGR™ systems have been successfully implemented at a number of contaminated sites (both large- and small-scale) located across the United States in diverse geologic settings helping to restore aquifers impacted by a range of contaminants.

As with any remedial technology, proper design and operation are critical to the success of a DGR™ system. Since DGR™ is a relatively new remedial technique, fundamental design and operating principles and practices have not yet been fully established. As such, a systematic approach for design and operation of an effective DGR™ system has been developed though our collective experience. Several examples are presented to illustrate the guiding principles of this approach and to highlight the computer-based tools that are applied.