"The Piceance basin of northwestern Colorado contains large reserves of oil shale. Expected development of oil shale will affect the regional hydrologic systems because most oil-shale mines will require drainage; industrial requirement for water may be large; and oil-shale mines, wastes, and retorts may affect the quantity and quality of surface water and ground water. In addition, the oil-shale industry may discharge particles and gases to the atmosphere that could alter the quality of high-altitude lakes and surface-water reservoirs. Hydrologic data need to be collected in order to plan for oil-shale development and to estimate the effects of development. Test-well drilling and aquifer testing are needed to provide a better understanding of the local and regional flow system, to furnish additional data for a model that stimulates mine drainage, and to explore for water supplies in aquifers of Paleozoic and Mesozoic age. Improved understanding of the hydrologic flow system also will result from additional studies of ground-water quality because major aquifers can be distinguished by certain dissolved constituents, and the solution of evaporate minerals affects water quality and permeability. Much of the ground water in the bedrock aquifers discharges through springs, and a systematic study of the springs will help to predict the effects of mine drainage on spring discharge and quality. Surface runoff, dissolved and suspended loads in streams, and the aquatic environment in streams would be highly susceptible to the disruptions in the land surface and will require additional study in order to estimate the effects of development. A water-quality assessment is proposed for the White River basin because it is a possible source of water and a region likely to be affected by development. The effects of emissions to the atmosphere from oil-shale plants require study because these emissions may affect the quality of water in lakes downwind. Spoil piles of retorted oil shale may be very large and require study to anticipate any problems caused by leaching and erosion. Processing wastes resulting from in-situ retorts and other waste materials need to be studied in greater detail in order to estimate their impacts on the hydrologic system."