Overview of the Toxic Substances Hydrology Program role in investigating the occurrence and fate of agricultural chemicals with links to investigations, headlines, on-line fact sheets, new publications, bibliographies and photo gallery.
Information on arsenic in United States ground water largely as a result of minerals dissolving from weathered rocks and soils. Includes links to publications, data, maps, and links to other sites with information on arsenic.
Well vulnerability results from the young age of groundwater. Karst features permit contaminants to move into the aquifer easily, leading to a well mixed aquifer; geochemical processes do not degrade contaminants quickly.
Stream water quality is affected by amount of impermeable surface in the basin; construction; reservoirs; sanitary sewer systems; land use and population density; road salt; animal waste; lawn and agricultural fertilizers, pesticides, and herbicides.