Author
Geological Survey (U.S.)
579
Geological Survey (U.S.),
340
SpringerLink (Online service)
101
National Water-Quality Assessment Program (U.S.)
95
Films for the Humanities & Sciences (Firm)
72
Infobase
72
United States. Environmental Protection Agency
58
United States. Environmental Protection Agency. Office of Water
40
ScienceDirect (Online service)
36
United States. Environmental Protection Agency. Office of Research and Development
32
United States. Environmental Protection Agency,
25
United States. Bureau of Reclamation
24
United States. Bureau of Land Management
22
U.S. Fish and Wildlife Service
18
New York (State). Department of Environmental Conservation
16
United States. Department of Energy
16
United States. Environmental Protection Agency. Health and Ecological Criteria Division
16
United States. Environmental Protection Agency. Office of Research and Monitoring
16
Wisconsin. Department of Natural Resources
12
Library of Congress. Congressional Research Service,
11
Colorado. Department of Public Health and Environment. Water Quality Control Division
10
Breault, Robert F.
9
Colorado. Department of Public Health and Environment
9
Massachusetts. Department of Environmental Protection
9
Monroe County (N.Y.). Department of Health
9
Wilson, Jennifer T., 1973-
9
Colorado. Water Quality Control Commission
8
Kansas. Department of Health and Environment
8
United States. Environmental Protection Agency. Great Lakes National Program Office
8
United States. National Park Service
8
Wild Hare Productions LLC
8
Battaglin, William A.
7
Canada. Environment Canada,
7
Colorado. Oil and Gas Conservation Commission
7
Sando, Steven Kent, 1956-
7
United States. Forest Service
7
Waskom, R. M.
7
Aberdeen Proving Ground (Md.). Environmental Conservation and Restoration Division
6
Barceló, Damià
6
Domagalski, Joseph L.
6
Fey, David L.
6
Great Lakes Environmental Research Laboratory
6
Hyer, Kenneth E.
6
Minnesota Pollution Control Agency
6
New Jersey. Department of Environmental Protection
6
Ortiz, Roderick F.
6
Parthenon Entertainment (Firm)
6
Phillips, Patrick J.
6
Pope, Larry M.
6
United States. Air Force
6
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