Six elements with human-health concerns were detected at high concentrations: arsenic, boron, fluoride, molybdenum, strontium, and vanadium. Lead was present at moderate concentrations.
Summary of chemical constituents of ground water that are of concern to human activity in this area. Arsenic is the constituent that occurs most frequently in high concentrations.
Arsenic and boron were the trace elements that most frequently occurred at high concentrations. Fumigants (pesticides) were detected at high concentrations in 3% of the primary aquifers. Herbicides and insecticides were detected at low concentrations.
Vanadium and boron were detected at high and moderate concentrations in this area. High concentrations for these constituents were detected almost exclusively in samples collected in the Temecula Valley study area.
Explains sources of mercury in the air, ways in which mercury is concentrated in animals, and describes how we measure deposition of atmospheric mercury, with summaries of observations.
Even though lead usage has declined due to environmental awareness and regulation, several human sources of lead continue to affect birds. Hunting ammunition and fishing gear are ingested by the birds, with toxic effects.
Explains the complex relationships between coal, mercury, and halogens in light of ongoing efforts to reduce the emission of mercury into the environment.
Research findings and examples of application to real problems--highly variable conditions cause the production of toxic methyl mercury in the environment which accumulates in fish.
Despite public sector efforts to reduce nonpoint-source nutrients in streams and rivers, concentrations have remained the same or increased, continuing to pose risks to aquatic life and human health.
An "image map" periodic table and short notes about many isotopes and their applications to illustrate the uses of assorted isotopes in hydrology, geology, and biology.
Explains why phosphorus is important, how it moves through the terrestrial water system, how we measure it, and what this means for people who need to manage or monitor human activities that produce it.
Estimates of known and undiscovered copper resources total nearly 60 million metric tons of copper. Iron resources in known deposits total 2200 million metric tons of ore. Twenty mineralized areas meriting further study were identified.
Knowledge of the geochemical processes controlling radium occurrence in groundwater may help water-resource managers anticipate and minimize human exposure to this cancer-causing element.
Report of completed reservoir sediment studies in Kansas using a combination of bathymetric surveying, sediment coring, chemical analysis, and statistical analysis to understand the quantity and quality of deposited sediment.