High-resolution Magnetic Resonance Sensors for In-situ Measurements of Soil Hydrogeology at Coastal Interfaces

This proposal addresses the problem of characterizing the geotechnical and hydrogeologic properties of natural sediments and engineered earthen infrastructure in coastal and riverine environments. This problem will be addressed through development and demonstration of innovative nuclear magnetic resonance (NMR) and cone penetrometer test (CPT) technologies that can be deployed manually, via lightweight off-road vehicles, and via underwater platforms. Vista Clara successfully achieved all major technical goals and commercialization milestones in the Phase II project. These goals include developing a family of relatively inexpensive, person-portable NMR sensors with a common control unit and simple deployment tools to enable scientists to perform high-resolution NMR-based investigations of environmentally sensitive coastal interfaces. In Phase II we introduced (1) high resolution Dart probes having a vertical resolution of up to 1.5-inches; (2) non-invasive unilateral Discus system; (3) Portable Helios core analyzer. The technical approach in Phase IIB is intended to broaden the impact of NMR-based geophysics in coastal and riverine infrastructure projects, by developing industrial-scale evolutions of these NMR sensors that can collect large amounts of NMR and CPT data rapidly and enable these CPT and NMR measurements to be performed in previously inaccessible environments. (1) development of a person- and vehicle-deployable Direct Push and CPT+NMR technology; (2) development and commercialization of small-scale towable non-invasive NMR technology; (3 Commercialization of personand vehicle-deployable NMR instruments through demonstration campaigns covering a wide range of coastal-related markets, customers, and applications. To date, typical approaches to characterize coastal and riverine infrastructure are based on land surveying (e.g., aerial photography, satellite imagery, LiDAR, and GIS), installing piezometers, collecting core samples for sediment analysis, and geotechnical methods such as ground penetrating radar (GPR) and cone penetration testing (CPT). These methods are labor and costintensive and do not provide accurate hydrogeologic characterization of critical coastal and riverine infrastructure, such as formation porosity and hydraulic conductivity. Commercialization of minimally invasive or non-invasive NMR and CPT+NMR-based technologies that provide real-time measurements of sediment geotechnical and hydrogeologic parameters will greatly reduce costs and uncertainties associated with traditional methods based upon core-extraction and laboratory analysis.