Publications

Mercury contamination of remote lakes has been attributed to increasing deposition of atmospheric mercury, yet historic deposition rates and inputs from terrestrial sources are essentially unknown. Sediments of seven headwater lakes in Minnesota and Wisconsin were used to reconstruct regional modern and preindustrial deposition rates of mercury. Whole-basin mercury fluxes, determined from lake-wid

The Edwards-Trinity aquifer system is underlain by an extensive complex of rocks, ranging from Late Cambrian through Late Triassic in age, that are typically about 10 to perhaps 1,000 times less permeable than those composing the aquifer system. The Cretaceous rocks of the aquifer system are separated from the pre-Cretaceous rocks by an unconformity that spans about 60 million years of erosion dur

A study of seasonally frozen soil was conducted from October 1985 through April 1986 and from October 1986 through April 1987. Three runoff plots were established. On October 30, 1985, 86 mm (millimeters) of water was applied to plot 1, and 43 mm of water was applied to plot 3. No water was applied to plot 2. The winter of 1985-86 had colder-than-normal air temperatures and greater-thannormal prec

No abstract available.

Trail Creek is a small (54.1-square-mile drainage area) tributary of Lake Michigan located in northwestern Indiana. A harbor at the mouth of the stream has experienced excessive sediment deposition. A study was done to investigate the suspended-sediment characteristics of Trail Creek. The study included analysis of suspended-sediment concentration and particle-size data, and estimates of annual su

No abstract available.

Selected physical, chemical and biological components of streams draining undeveloped, forested basins in North Carolina were characterized on the basis of samples collected at nine sites on streams in basins that ranged in size from 0.67 to 11.2 sq mi. Water analysis included specific conductance, dissolved oxygen, water temperature, suspended sediment, pH, major dissolved constituents, nutrients

No abstract available.

The feasibilityty of using noninvasive flowmeters for determining water use was investigated by attempting, and at some sites repeating, instantaneous pipe-flow measurements at 45 water-withdrawal sites by use of four portable noninvasive pipe flowmeters. The flowmeters measure flow in pipes; this flow is related to water use. Because actual water use can differ from the total flow in the pipe, wa

No abstract available.

No abstract available.

The headwaters of the Conestoga River are being studied to determine the effects of agricultural Best-Management Practices on surface-water and ground-water quality. As part of this study, a 5.82-square-mile area of the Little Conestoga Creek headwaters (Small Watershed) was monitored during 1984-86, prior to implementation of Best-Management Practices. This report describes the land use and hydro