SGER: Measurement of the Electrical and Dielectric Properties of Degrading Refuse for Application of Borehole Ground Penetrating Radar to Monitoring Landfill Bioreactors

University Of Arizona, Tucson AZ

Investigators

Abstract

0097171 Ferre The objective of this project is to explore the use of borehole ground penetrating radar (GPR) for the measurement of water content in landfills by studying the relationship of the electrical and dielectric properties of decomposing refuse with its water content. Specifically, two key issues underlying the use of borehole GPR for water content measurement will be addressed: (1) determination of the frequency-dependent electrical and dielectric properties of decomposing refuse and (2) definition of the spatial sensitivity of the borehole GPR method to spatially variable electrical and dielectric properties. Laboratory column experiments will be conducted to fulfill the first goal. To fulfill the second goal, analytical and numerical methods previously developed by the PI will be extended to fit the borehole GPR situation; these analytical descriptions will be field tested for one year in an operating landfill of the City of Tucson as a part of its reclamation of the historic Rio Nuevo district. Better measurement and monitoring of water content in a bio-reactor landfill is important to its operation. Too much water impedes the flow of air through the refuse slowing the rate of degradation; insufficient moisture can lead to increased subsurface temperatures, reduced reaction rates and the potential for subsurface combustion. Other environmental applications dependent upon measurement of volumetric water content of the subsurface include estimation of natural recharge, optimization of artificial recharge and soil aquifer treatment operations, monitoring of slope stabilization and isolation of hazardous wastes. ***