The coal reserves in the United States are well known, both as to geologic age and geographic distribution. The largest reserves must be obtained by underground mining methods (about 327 billion tons in the east; 22 billion tons in the west), with approximately 35 billion tons obtainable from surface mining in the western United States and 10 billion tons from the eastern states. Equipment manufacturers rather than the mining companies have been largely responsible for the improvement of underground technology with a gradual productivity improvement through the years until the enactment of recent health and safety legislation which has caused a 20 to 30 percent drop in underground productivity. Openpit-mining methods have been developed since 1900; today's equipment is sa isfactory for current and future operations.

Capital availability, which has been a problem in coal mining in the past, probably will not be of future concern if coal is required as an energy fuel. Reserve ownership has never been a problem with the eastern coal mines, but is a serious consideration in the west where the government owns most of the coal reserves. The availability of western coal reserves will depend to a great extent on solving environmental problems.

The economics of coal mining have been traditionally controlled by the quality of the coal, the cost of production, and the cost of transportation. Environmental considerations have upset the usual supply and demand pattern, and may cause further serious readjustments in mining and marketing practices. To establish a realistic energy mix, coal must be made a socially acceptable fuel; this will require moderation of some of today's environmental controls and acceptance of increased costs in order that coal may assume its projected usage for energy needs by 1978.