Surface NMR Instrumentation and Analysis Methods for Characterizing Vadose Zone Hydrology

The Department of Energy is responsible for the investigation and remediation of large-scale subsurface contamination at several existing and former DOE facilities. An understanding the hydrogeology of the vadose zone is crucial to understanding the transport and fate of underground contaminants. This project will develop practical field-based measurement and analysis techniques for determining vadose zone transport properties from multi-coil surface NMR measurements. Phase I demonstrated the theoretical and practical basis for using surface NMR geophysics to detect and characterize vadose zone water, and to translate the NMR signal properties of vadose zone water into hydraulic properties and/or transport models at the site scale. Phase II will entail the full-scale development of vadose-zone surface NMR instrumentation and analysis methods, coupled with extensive laboratory and field testing at DOE facilities, in order to demonstrate proof-of-principle. Commercial Applications and other Benefits as described by the awardee: The surface NMR instrumentation and analysis techniques should enable high-resolution, non-invasive measurements of gravitational, capillary, and clay-bound water content in the unsaturated zone. In turn, these measurement capabilities would enable the more accurate prediction of contaminant transport and aquifer recharge processes. Vadose zone properties are especially important to assessing the feasibility and efficacy of aquifer storage and recovery projects.