Overview of fractured rock research aimed at understanding the movement of water through fracture networks, and characterize field conditions influencing contaminant migration. Includes programs and publications.
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.
Description of the project to publish new bedrock geologic maps in the United States to advance the understanding of the region's bedrock aquifers. Includes list of projects.
Homepage of the Office of Water Quality programs on the quality of the Nation's surface water and ground water resources, with links to general information, quality assurance, software, data, publications, USGS facilities, techniques, and programs.
Five trace elements with human-health concerns were detected at high concentrations: arsenic, boron, fluoride, molybdenum, and strontium. Vanadium was present at moderate concentrations.
Trace elements were present at high concentrations in 32% of the primary aquifers here, and at moderate concentrations in 17%. Of particular interest are aluminum, arsenic, vanadium, boron, fluoride, chromium, lead, and molybdenum.
Recent study indicates that inorganic trace elements and radioactive constituents are more likely to be subjects of concern in this less-developed area than anthropogenic organic compounds.
The occurrence of solvents in the groundwater is not correlated with current overlying land use and human activities. Rather, the solvents are from legacy industrial uses, and it has taken decades for the groundwater to move to where it is now pumped.
Five trace elements with human-health concerns were detected at high concentrations: arsenic, boron, fluoride, molybdenum, and strontium. Chromium was detected at moderate concentrations.
Five trace elements with human-health concerns were detected at high concentrations: arsenic, boron, molybdenum, strontium, and vanadium. Chromium and fluoride were detected at moderate concentrations.
Arsenic was the trace element most frequently present at high concentrations here. High concentrations of arsenic result from the interaction of groundwater with naturally occurring minerals.
Uranium, arsenic, and nitrate were the inorganic constituents that were most frequently detected at high concentrations, mostly in shallower wells. High and moderate concentrations of arsenic were detected in deeper wells.
Results of a survey of contaminants in untreated groundwater in this area. Arsenic and boron were the two trace elements detected most frequently at concentrations greater than the benchmarks.
Six elements with human-health concerns were detected at high concentrations: arsenic, boron, fluoride, molybdenum, strontium, and vanadium. Lead was present at moderate concentrations.
This study of untreated groundwater indicates the number of samples in which inorganic or organic constituents occur in high or moderate in concentration. The study does not indicate significant problems in groundwater quality here.
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.
Organic solvents are the chief concern in this area, which has given rise to a systematic program of monitoring and water treatment. This study shows relatively recent results.
The constituent present at high concentrations in the greatest proportion of the primary aquifer system was TDS, which is an indicator of salinity. Perchlorate was also present at moderate concentration in 42% of samples.
This study of untreated groundwater indicates the number of samples in which inorganic or organic constituents occur in high or moderate in concentration. The study does not indicate significant problems in groundwater quality here.
Arsenic and nitrate are the constituents found most commonly at high concentrations in the primary aquifers. Arsenic comes from natural sources and is affected by pH and dissolved oxygen.
Results of a survey of contaminants in untreated groundwater in this area. Arsenic and boron were the trace elements occurring most frequently at high concentrations.
Recent study indicating inorganic constituents as the primary items of concern in this area. Chemical and mineralogical compositions of the aquifer rocks probably explain variation among localities here.
Recent study encountered occasional high values of radioactive trace elements, but the water quality in this area as monitored compares favorably to more urban areas studied by the same group.
Recent study indicating nitrate and perchlorate are the primary inorganic constituents of interest here, coming from human activities such as agriculture.
Study of the susceptibility and vulnerability of basin-fill aquifers in the region to ground-water contamination by synthesizing the information on ground-water quality conditions in 15 basins from previous studies.
Map of California showing the number of wells (by county) with available water-level or water-quality data for Water Year 2010, with descriptions of the data and instructions for obtaining them.
Explains why we are assessing water quality in shallow aquifers, what we are measuring, and how the results will be reported both to well owners and to the public.
Recent increases in dissolved-solids concentrations in this aquifer have been documented in some areas used for public supply, raising concerns as to the sources and causes of the higher concentrations and the long-term effects on groundwater quality.
National Water Information System (NWIS) real-time data on selected ground water sites, ground water level data, site inventory of wells, test holes, drains, springs and excavations and ground water-quality data for the United States.
Sampling program to determine if pesticides are present in ground water, in accordance with Wyoming's Generic State Management Plan for Pesticides in Ground Water (SMP).
Shallow groundwater has good quality, but salinity measured in wells suggests the thin lens of freshwater under the coastal plain will be vulnerable to saltwater intrusion as a consequence of pumping.
Lower precipitation and recharge, with deeper groundwater levels, suggest this basin will be less susceptible to contamination than others nearby, but may be susceptible to saltwater intrusion brought on by well pumping.
Study of pesticides in shallow groundwater and surface water to help decision makers evaluate and manage pesticide application practices to protect drinking water resources, especially deeper, potable groundwater as well as aquatic species.
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.
Short descriptions of the research and monitoring activities we are carrying out to assist state, local, and Federal agencies dealing with water resource issues in the southern part of the state.
Overview of project assessing water quality of the Tualatin River basin near Portland, Oregon with links to reports on chemical and nutrient levels and selected data on streamflow, water temperature, weather and precipitation.
Map of New Jersey showing the locations of all well sites where ground water-quality data exists in the USGS National Water Information System (NWIS) database.
Arsenic is a naturally occurring element in rocks, soils, and the waters in contact with them. It is found in ground water as the result of minerals dissolving from weathered rocks and soils. This site links to data, maps, and more.
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.
Using ground-water geochemical analyses, and mathematical models, the factors affecting the quality of public water supply were identified as pumping schedule, screened interval, past land use within the recharge area, and natural geochemical conditions.
Using ground-water geochemical analyses and mathematical models, the factors affecting the quality of public water supply were identified as mixing of very recent recharge with older water, karst features, natural geochemical processes, and pumping.