Geologic features such as structure, water bearing zones, aquifers, permeability variations, porosity variations and overburden strength, along with the coal type, are important in the successful operation of the underground coal gasification process. Boreholes are an absolute necessity to provide certain types of information, however, due to the cost of drilling/coring and logging, and complex geologic structure, the areal variability of geologic features would be difficult to establish by borehole alone. Surface, surface-to-borehole, and cross-borehole geophysical surveys can help by more precisely defining the geologic environment of the coal occurance, as well as the lateral continuity or areal distributor of the geologic deatures and the coal seam. Various geophysical techniques might be used to obtain the necessary geologic information. However, in general, geophysical methods, field procedures, and data analysis have not been applied to in situ process site characterization activities. Generally, the application of existing techniques to site characterization problems requires changes and improvements in field procedures and modeling, and well require the inversion of the multiple data sets to determine the pertinent parameters. The improvements necessary in existing geophysical techniques for the site characterization activities will be discussed in this paper.