Search Results

Stratified-drift aquifers, the major source of large quantities of groundwater in Connecticut, are recharged principally by (1) precipitation that infiltrates the land surface overlying the aquifer and percolates downward to the saturated zone, (2) subsurface inflow of groundwater from adjacent till-and-bedrock uplands, and (3) surface water that infiltrates through streambed...

Prompted by the need for a current, accurate, and repeatable delineation of irrigated acreage on the Snake River Plain, the U.S. Geological Survey entered into a cooperative agreement with the Idaho Department of Water Resources Image Analysis Facility and the U.S. Bureau of Reclamation to delineate 1980 land use form...

No abstract available....

In 1977, the U.S. Geological Survey began a series of investigations of regional aquifer systems in the United States. These studies will provide quantitative information for use in developing and managing regional ground-water supplies. One of these studies, the Northern Midwest Regional Aquifer-System Analysis (RASA) project, concerns the Cambrian and...

Certain physical characteristics of soils, including permeability, available water capacity, thickness, and topographic position, have a definite effect on the hydrology of an area. They control the rate at which precipitation infiltrates or is transmitted through the soil, and thus they have a significant role in determining the rates both...

No abstract available....

The Great Basin Regional Aquifer-System Analysis (RASA) is the tenth study in a national program b the U.S. Geological Survey to analyze regional ground-water systems that comprise a major part of the Nation’s water supply. The main objectives of RASA studies are to: (1) Describe the ground-water systems as they...

No abstract available....

Groundwater is the major source of water in Linn County and the surrounding area. Approximately 90 percent of the groundwater production is from Silurian, Devonian, and Quaternary aquifers. The Silurian and Devonian aquifers consist of limestone and dolomite with minor shale beds, which have a regional dip to the southwest of...

Forty-eight core samples of ash-flow tuffs from Yucca Mountain, NV, were selected for comparative analysis by uranium-based methods to estimate past interaction with oxidizing water. Results aid in the selection of hydrologically isolated host rocks for radioactive waste disposal. U abundances were consistently more variable than thorium in whole rocks,...

No abstract available....

No abstract available....

Anaerobic San Francisco Bay salt marsh sediments rapidly metabolized [14C]dimethylselenide (DMSe) to 14CH4 and 14CO2. Addition of selective inhibitors (2-bromoethanesulfonic acid or molybdate) to these sediments indicated that both methanogenic and sulfate-respiring bacteria could degrade DMSe to gaseous products. However, sediments taken from the selenium-contaminated Kesterson Wildlife Refuge produced only 14CO2 from [14C]DMSe, implying that...

A new formula is presented for the analytical solution of the radial dispersion problem, which analyzes the dispersive transport of a tracer in radial flow from a recharge well. This formula is simpler than a solution presented by previous investigators, but the two solutions are shown to be equivalent. Because...

The emphasis on harmful substances that may occur in potable waters has almost obscured the fact that important beneficial constituents are commonly present.The chemical substances in water that make positive contributions to human health act mainly in two ways: (i) nutritionally, by supplying essential macro and micro elements that the...

Increasing demands on stream resources by a variety of users have resulted in an increased emphasis on studies that evaluate the cumulative effects of basinwide water management programs. Network habitat analysis refers to the evaluation of an entire river basin (or network) by predicting its habitat response to alternative...