For the characterization component of the FRGT, this project will demonstrate the performance of four under-exploited technologies:
- directional borehole ground penetrating radar (DBHGPR) for providing unique high-resolution data on fracture strike and dip
- resistivity and induced polarization (IP) imaging for visualizing the spatial distribution of fracture density and fracture surface area
- azimuthal self potential (ASP) for determining spatial variability in bulk hydraulic anisotropy in fractured bedrock
- new borehole IP and nuclear magnetic resonance (NMR) tools improving assessment in vertical distribution of physical parameters controlling mass transfer.
For the DNAPL monitoring component of the toolkit, this project will demonstrate the performance of
- electrical resistivity imaging for tracking changes in bulk conductivity sensitive to changes in groundwater chemistry accompanying DNAPL degradation
- self potential (SP) imaging of the changes in the distribution of natural current sources resulting from redox zonation produced by DNAPL degradation
- electrodic potential (EP) monitoring of changes in redox chemistry local to electrodes.
The data analysis component will demonstrate how new inversion technologies can (1) better characterize fracture networks in terms of bulk conductivity, chargeability, and source current, respecting specialized model constraints derived from borehole, ASP, and DBHGPR data and (2) reconstruct the changes in geophysical attributes that are related to DNAPL biodegradation using constraints that are encouraged to limit changes within the images to discrete fractures or fracture zones identified during the characterization phase.