This report applies a basin-scale coalbed methane producibility model in defining fairways and sweet spots in three coal basins in the United States. The Bureau of Economic Geology, The University of Texas at Austin, has developed a basin-scale coalbed methane producibility and exploration model based on a decade of Gas Research Institute-supported research performed in the San Juan, Sand Wash (Greater Green River), and Piceance Basins and on reconnaissance studies of several other producing and prospective coal basins in the United States.

Of the more than 19,000 documented leaking petroleum storage tank (LPST) sites in Texas, more than 6,000 have impacted ground water and resulted in fuel hydrocarbon (FHC) plumes. The sheer number of regulated facilities and their wide geographical distribution throughout the state, however, have made gaining a regional perspective on hydrocarbon plumes difficult.

Analysis of spatial variability in unsaturated flow is critical to evaluating contaminant transport in areas of focused or preferential flow. This study examined spatial variability at a variety of scales from focused flow through playas to preferential flow in macropores. A total of 39 boreholes from 7 playa and adjacent interplaya settings on the Southern High Plains of Texas were sampled for hydraulic and hydrochemical parameters. To evaluate preferential flow in surficial sediments, we applied bromide and organic dyes.

This study used a numerical model to examine the playa-focused recharge theory by comparing it with the spatially uniform approach and with a zonal approach. Much recent hydrologic, geologic, and chemical evidence suggests that the approximately 19,250 seasonal lakes on the Southern High Plains of Texas and New Mexico, commonly known as playas, are the principal focal points of recharge to the Ogallala aquifer.