Author
SpringerLink (Online service)
2,716
Geological Survey (U.S.)
2,168
Geological Survey (U.S.),
1,226
ScienceDirect (Online service)
823
Infobase,
672
United States. Environmental Protection Agency
524
Films for the Humanities & Sciences (Firm)
416
Infobase
408
National Water-Quality Assessment Program (U.S.)
307
Library of Congress. Congressional Research Service,
296
United States. National Park Service. Natural Resource Stewardship and Science,
263
United States. Bureau of Land Management
252
United States. National Park Service
228
SpringerLink (Online Service)
225
United States. Forest Service
224
Natural Resource Program Center (U.S.),
205
United States. Environmental Protection Agency,
203
United States. Environmental Protection Agency. Office of the Inspector General,
196
United States. Congress. Senate. Committee on Environment and Public Works
194
United States. Environmental Protection Agency. Office of Research and Development
179
United States. Congress. Senate. Committee on Environment and Public Works,
176
U.S. Fish and Wildlife Service
163
United States. Forest Service,
159
United States. Environmental Protection Agency. Office of Water
157
United States. Environmental Protection Agency. Office of Transportation and Air Quality,
150
United States. Federal Highway Administration
136
National Risk Management Research Laboratory (U.S.)
133
United States. Environmental Protection Agency. Office of the Inspector General
131
United States. Environmental Protection Agency. Office of Solid Waste and Emergency Response
127
Public Broadcasting Service (U.S.)
123
United States. Department of Energy
117
Oxford Scholarship Online
115
United States. Agency for Toxic Substances and Disease Registry
115
United States. Agency for Toxic Substances and Disease Registry,
112
SmartWay Transport Partnership Program (U.S.),
107
EBSCOhost
106
United States. Environmental Protection Agency. Office of Air Quality Planning and Standards
105
United States. Environmental Protection Agency. Transportation and Climate Division,
95
United States. Bureau of Reclamation
92
United States. Congress. House. Committee on Transportation and Infrastructure,
86
Risk Reduction Engineering Laboratory (U.S.)
85
United States. Army. Corps of Engineers
82
Muthu, Subramanian Senthilkannan,
77
Colorado. Department of Public Health and Environment
76
Colorado. Department of Transportation
74
National Renewable Energy Laboratory (U.S.),
74
United States. Federal Energy Regulatory Commission. Office of Energy Projects
73
National Renewable Energy Laboratory (U.S.)
69
Air and Energy Engineering Research Laboratory
67
United States. Congress. House. Committee on Transportation and Infrastructure
67
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