Subject
Reclamation of land
10
Reclamation of land History
8
Strip mining Environmental aspects
4
Water resources development History
4
History
3
Dams History
2
Hydroelectric power plants History
2
Irrigation History
2
Water-power History
2
Abandoned mined lands reclamation
1
Acid mine drainage Environmental aspects
1
Arid regions
1
Coal mines and mining
1
Coal mines and mining Environmental aspects
1
Community life History
1
Environmental policy History
1
Farmers History
1
Frontier and pioneer life
1
Irrigation Environmental aspects History
1
Irrigation projects
1
Land use
1
Mine soils
1
Mineral industries Environmental aspects
1
Mines and mineral resources
1
Mines and mineral resources Environmental aspects
1
Revegetation
1
Soils, Salts in
1
Spoil banks
1
Sustainable agriculture History
1
Veterans History
1
Water resources development
1
Water-supply Economic aspects History
1
Water-supply Government policy History
1
West (U.S.) Economic conditions
1
West (U.S.) Environmental conditions
1
West (U.S.) History
1
West (U.S.) Social life and customs
1
Wildlife conservation
1
World War, 1939-1945 Veterans
1