Publications

No abstract available.

No abstract available.

Field replicate water samples (“field replicates”) collected for the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program during 1992 to 1997 were used to assess the variability of pesticide detections and concentrations in environmental water samples collected from the surface-and ground-water-quality networks of the NAWQA Program. Field replicates are two or more identically

This report provides equations for estimating mean annual streamflow, mean monthly streamflows, harmonic mean streamflow, and streamflow quartiles (the 25th-, 50th-, and 75th-percentile streamflows) as a function of selected basin characteristics for rural, unregulated streams in Ohio. The equations were developed from streamflow statistics and basin-characteristics data for as many as 219 active

In Idaho, drinking-water supplies are pumped from relatively shallow ground-water zones where water quality has great potential for degradation by land- and water-use activities. One indicator of water quality, and one of the most widespread contaminants in Idaho ground water related to land and water uses, is dissolved nitrate. In December 2000, the U.S. Geological Survey, in cooperation with the

Borehole geophysical logging and aquifer-isolation (packer) tests were conducted at the North Penn Area 5 Superfund site in Bucks and Montgomery Counties, Pa. Caliper, naturalgamma, single-point-resistance, fluid-temperature, fluid-resistivity, heatpulse-flowmeter, and digital acoustic-televiewer logs and borehole television surveys were collected in 32 new and previously drilled wells that ranged

Data for all 366 known streamflow gain-loss studies conducted by the U.S. Geological Survey in Texas were aggregated. A water-budget equation that includes discharges for main channels, tributaries, return flows, and withdrawals was used to document the channel gain or loss for each of 2,872 subreaches for the studies. The channel gain or loss represents discharge from or recharge to aquifers cros

The Commonwealth of Pennsylvania has water-quality standards that limit the number of specific bacteria in water that is considered safe for recreational use. Bacteria such as fecal streptococci, fecal coliforms, and Escherichia coli (E. coli) are used to assess recreational water quality because they usually live in the intestines of warm-blooded animals. Fecal indicator bacteria commonly are ass

Lake Pontchartrain is the largest estuary southern Louisiana. It is an important recreational, commercial, and environmental resource for New Orleans and southwestern Louisiana. This publication is part of a 5-year cooperative program led by the USGS on the geological framework and sedimentary processes of the Lake Pontchartrain Basin.This presentation is divided into two main parts:- Scientific R

A recent national sampling of streams in the United States revealed low methyl mercury concentrations in surface waters. The resulting median and mean concentrations, calculated from 104 samples, were 0.06 nanograms per liter (ng/L) and 0.15 ng/L, respectively. This level of methyl mercury in surface water in the United States has created a need for analytical techniques capable of detecting sub-n

No abstract available.

This surface-water quality-assurance plan documents the standards, policies, and procedures used by the Wisconsin District of the U.S. Geological Survey, Water Resources Division, for activities related to the collection, processing, storage, analysis, management, and publication of surface-water data. The roles and responsibilities of District personnel in following these policies and procedures