Geology 264 Kentucky 67 Groundwater 49 Geology, Stratigraphic 45 Water quality 37 Coal 33 Water-supply 26 Paleontology 25 Mines and mineral resources 19 Groundwater flow 18 Hydrogeology 18 Hydrology 18 Fluorspar 17 Stream measurements 16 Kentucky History 15 National parks and reserves 14 Abraham Lincoln Birthplace National Historical Park (Ky.) 13 Geology, Structural 12 Aquifers 11 Historic sites 11 Streamflow 11 Water Pollution 11 Coal mines and mining 10 Military education 10 Daniel Boone National Forest (Ky.) 9 Groundwater Pollution 9 Coal Geology 8 Water Composition 8 Frontier and pioneer life 7 Groundwater Quality 7 Hydroelectric power plants Licenses 7 Outdoor recreation 7 Pesticides Environmental aspects 7 Petrology 7 Strip mining Environmental aspects 7 Water quality Measurement 7 Water quality management 7 Buildings 6 Coal Sampling 6 Coal mines and mining Environmental aspects 6 Freshwater biology 6 Geochemical prospecting 6 Hydroelectric power plants Law and legislation 6 Limestone 6 Paleobotany 6 Trails 6 Wages 6 Birthplace 5 Borings 5 Coal preparation 5 Cumberland Gap National Historical Park 5 Earthquakes 5 Environmental monitoring 5 Gaseous diffusion plants Environmental aspects 5 Groundwater tracers 5 Kentucky Description and travel 5 Management 5 Nuclear industry Employees Health and hygiene 5 Nutrient pollution of water 5 Officials and employees 5 Oil fields 5 Petroleum 5 Petroleum Geology 5 Reelfoot National Wildlife Refuge (Tenn. and Ky.) 5 Suspended sediments 5 Wildlife refuges 5 Coal Carbonization 4 Coal reserves 4 Fast food restaurants 4 Faults (Geology) 4 Flood forecasting 4 Floods 4 Folk music 4 Forests and forestry 4 Geomagnetism 4 Grants-in-aid Auditing 4 Homes and haunts 4 Indiana 4 Industrial water supply 4 Kentucky Altitudes 4 Mammoth Cave National Park (Ky.) 4 Music Instruction and study 4 Music Performance 4 Musical form 4 Occupational diseases 4 Oil-shales 4 Paleoecology 4 Palynology 4 Radioactive pollution 4 River sediments 4 Style, Musical 4 Tennessee 4 Wages Food industry and trade 4 Water consumption 4 Water table 4 Water use 4 Academic achievement 3 Authors, American 3 Big South Fork National River and Recreation Area (Tenn. and Ky.) 3 Bridges Law and legislation 3