Coal accounts for a major portion of our Nation's energy supply in projections for the future. A demonstrated reserve base of more than 475 billion short tons, as the Department of Energy currently estimates, indicates that, on the basis of today's rate of consumption, the United States has enough coal to meet projected energy needs for almost 200 years. However, the traditional procedures used for estimating the demonstrated reserve base do not account for many environmental and technological restrictions placed on coal mining. A new methodology has been developed to determine the quantity of coal that might actually be available for mining under current and foreseeable conditions. This methodology is unique in its approach, because it applies restrictions to the coal resource before it is mined. Previous methodologies incorporated restrictions into the recovery factor (a percentage), which was then globally applied to the reserve (minable coal) tonnage to derive a recoverable coal tonnage. None of the previous methodologies define the restrictions and their area and amount of impact specifically. Because these restrictions and their impacts are defined in this new methodology, it is possible to achieve more accurate and specific assessments of available resources. This methodology has been tested in a cooperative project between the U.S. Geological Survey and the Kentucky Geological Survey on the Matewan 7.5-minute quadrangle in eastern Kentucky. Pertinent geologic, mining, land-use, and technological data were collected, assimilated, and plotted. The National Coal Resources Data System was used as the repository for data, and its geographic information system software was applied to these data to eliminate restricted coal and quantify that which is available for mining. This methodology does not consider recovery factors or the economic factors that would be considered by a company before mining. Results of the pilot study indicate that, of the estimated original 986.5 million short tons of coal resources in Kentucky's Matewan quadrangle, 13 percent has been mined, 2 percent is restricted by land-use considerations, and 23 percent is restricted by technological considerations. This leaves an estimated 62 percent of the original resource, or approximately 612 million short tons available for mining. However, only 44 percent of this available coal (266 million short tons) will meet current Environmental Protection Agency new-source performance standards for sulfur emissions from electric generating plants in the United States. In addition, coal tonnage lost during mining and cleaning would further reduce the amount of coal actually arriving at the market.