Subject
Groundwater
11
Geomagnetism
10
Magnetic anomalies
9
Groundwater flow
7
Hydrogeology
7
Water quality
6
Anthracite coal
4
Aquifers
4
Coal Geology
4
Hydrology
4
Water-supply
4
Geology
3
Geophysical well logging
3
Groundwater Pollution
3
Stream measurements
3
Flood control
2
Water Analysis
2
Acid pollution of rivers, lakes, etc
1
Acid precipitation (Meteorology) Environmental aspects
1
Agricultural pollution
1
Atmospheric radioactivity
1
Bacterial pollution of water
1
Boring
1
Climatic classification
1
Cluster analysis
1
Coal
1
Coal mines and mining Environmental aspects
1
Crystalline rocks
1
Earthquakes
1
Groundwater Quality
1
Groundwater Sampling
1
Nitrates Physiological effect
1
Nutrient pollution of water
1
Pennsylvania
1
Philadelphia (Pa.) Climate
1
Pittsburgh Region (Pa.)
1
Radioactive pollution of water
1
Radium
1
Radon
1
Sanitary landfills
1
Seismology
1
Springfield (Bucks County, Pa. : Township)
1
Stream conservation
1
Streamflow
1
Streamflow velocity
1
Susquehanna River, West Branch (Pa.)
1
Terracing
1
United States PA Lancaster Co
1
United States PA Lebanon Co
1
United States PA Lititz Quad
1
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