Objective

The environmental issue addressed in this proposal is better delivery of amendments to the subsurface by a combination of innovative emplacement techniques and amendment monitoring techniques. Specifically, the proposed work will show how geophysical imaging can be used to verify the placement and subsurface distribution of amendments. The uncertainty associated with in-situ remediation of contaminated groundwater starts with uncertainty in the site conceptual model for amendment delivery, which will lead to uncertainties in remedial cost and remedial performance. Through coupled laboratory and field experimentation followed by a cost-benefit analysis, this project will assess the utility of time-lapse geophysical methods for monitoring fracture and amendment distribution and the utility of geophysical monitoring methods for providing information on amendment diffusion rates. We will also evaluate the utility and cost effectiveness of geophysical methods for developing and validating an amendment delivery strategy relative to conventional approaches (i.e., invasive soil coring) and review the utility of geophysical datasets collected post-delivery in a static mode to detect fracture and amendment distribution without the luxury of having a baseline image or performing time-lapse imaging.