Geology 78 Maine 77 Geomagnetism 42 Acadia National Park (Me.) 25 Stream measurements 22 Streamflow 22 Floods 20 Paleontology 20 Water quality 18 Geology, Stratigraphic 16 Petrology 15 Birds 9 Flood damage prevention 9 Groundwater Pollution 9 Hydroelectric power plants Environmental aspects 9 Maine History 9 Mines and mineral resources 9 Watersheds 9 Environmental monitoring 8 Forests and forestry 8 Hydrogeology 8 New Brunswick 8 Climatic changes 7 Granite 7 Hydrology 7 National parks and reserves Law and legislation 7 Wildlife refuges 7 Geology, Structural 6 Manganese 6 Québec (Province) 6 Rachel Carson National Wildlife Refuge (Me.) 6 Runoff 6 Transportation Environmental aspects 6 United States History 6 Acadia National Park (Me.) Environmental conditions 5 Auditing 5 Groundwater 5 Groundwater flow 5 Land use Law and legislation 5 Manganese ores 5 New Hampshire 5 Peat 5 Vermont 5 Volcanic ash, tuff, etc 5 Water Pollution 5 Wetlands 5 Acadia National Park (Me.) Boundaries 4 Coal 4 Corals, Fossil 4 Evaluation 4 Families 4 Friendship 4 Geochemistry 4 Geophysics 4 Groundwater Quality 4 Historic sites 4 Indians of North America 4 Maine Altitudes 4 National parks and reserves 4 Natural resources 4 Pegmatites 4 Roads Environmental aspects 4 Sea level 4 Seismic prospecting 4 Wild and scenic rivers Law and legislation 4 York River (Me.) 4 Arsenic Environmental aspects 3 City and town life 3 Copper ores 3 Flood damage 3 Forest management 3 Forest surveys 3 Frontier and pioneer life 3 Grants-in-aid Auditing 3 Gravity stations 3 Hazardous waste sites 3 Ice on rivers, lakes, etc 3 Interstate agreements 3 Land titles Registration and transfer 3 Landscape assessment 3 Landscape protection 3 Management 3 Manganese mines and mining 3 Marine sediments 3 Mineralogy 3 Moosehorn National Wildlife Refuge (Me.) 3 Mount Desert Island (Me.) 3 Moving, Household 3 Natural gas pipelines Environmental aspects 3 Natural history 3 New York (N.Y.) 3 Orphans 3 Outdoor recreation 3 Petit Manan National Wildlife Refuge (Me.) 3 Precipitation (Meteorology) 3 Saint Croix Island International Historic Site (Me. and N.B.) 3 Salt marshes Management 3 Sandstone 3 Schools 3 Soldiers 3