Publicity given to the detrimental effects of mining activities on the environment has tended to overshadow somewhat the hydrologic opportunities and benfits that could be associated with these activities. For example, many areas disturbed by surface mining have proved to be excellent recharge areas for groundwater aquifers. The degree to which mine sites can be exploited to improve management of the hydrologic system depends on both the local geology and the mining techniques used. The report examines the effects of present mining activities on the associated hydrology system, and identifies specific mining procedures and management techniques which not only minimize negative hydrologic impacts of mining operations, but which also enhance the values of the hydrologic system in terms of existing and potential social uses. Thus, the results of the research contribute to the solution of present and future hydrologic problems (both quanitty and quality) associated with coal mining in the western U.S. Emphasis is placed on sites which are representative of both existing and future coal mining areas. The specific objectives of the study are to: 1. Evaluate the potential for using underground coal mines to: a. Tap previously inaccessible groundwater supplies. b. Reduce the salt load to the Colorado River by decreasing the contact of groundwater with salt-bearing geologic formations. c. Store water in abondoned mines. 2. Consider the potential effects of underground coal mines on water resources. 3. Evaluate the potential of using surface mined areas to collect surface runoffs and thus: a. Reduce the sediment loads to the Colorado River. b. Enhance water storage in the basin. Each of the preceding objectives is addressed and discussed by the report in terms of actual coal mines in central Utah. The study suggests not only ways of reducing negative hydrologic impacts of mining operations, but also operational and management mining techniques which will enhance the social use value of the hydrologic systems, and thus, in fact, create hydrologic opportunities
