Publications

Precipitation and aggregation of metacinnabar (black HgS) was inhibited in the presence of low concentrations (≥3 mg C/L) of humic fractions of dissolved organic matter (DOM) isolated from the Florida Everglades. At low Hg concentrations (≤5 × 10-8 M), DOM prevented the precipitation of metacinnabar. At moderate Hg concentrations (5 × 10-5 M), DOM inhibited the aggregation of colloidal

The development and distribution of phytoplankton blooms in estuaries are functions of both local conditions (i.e. the production-loss balance for a water column at a particular spatial location) and large-scale horizontal transport. In this study, the second of a 2-paper series, we use a depth-averaged hydrodynamic-biological model to identify transport-related mechanisms impacting...

Water samples collected during April−November 1997 from tile drains beneath cultivated fields in central New York indicate that two metabolites of the herbicide metolachlormetolachlor ESA (ethanesulfonic acid) and OA (oxanilic acid)can persist in agricultural soils for 4 or more years after application and that fine-grained soils favor the transport of metolachlor ESA over metolachlor...

A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale...

No abstract available.

No abstract available.

Extensive development on Long Island since the late 19th century and projections of increased urbanization and ground-water use makes effective water-resource management essential for preservation of the island's hydrologic environment and maintenance of a reliable source of water supply. This report presents results of a ground-water flow simulation analysis of the effects of...

No abstract available.

Twelve monitoring wells were installed in 1997 at seven sites in and near Oasis Valley, Nevada. The wells, ranging in depth from 65 to 642 feet, were installed to measure water levels and to collect water-quality samples. Well-construction data and geologic and geophysical logs are presented in this report. Seven geologic units were identified and described from samples collected during...

From 1981 through 1986, the U.S. Geological Survey investigated the ground-water system of western Long Island, New York, including Kings and Queens counties. This report describes the structure and operation of the western part of the Long Island ground-water system, and the hydrologic effects associated with human development from 1900 to the early 1980's. Recent (early 1980's) ground...

Radiometric detection headspace analyses of microcosms containing bed sediments from two geographically distinct sites indicated that 10-39% of the radiolabeled carbon transformed during anaerobic biodegradation of [1,2- 14C]trichloroethene (TCE) or [1,2-14C]vinyl chloride (VC) under methanogenic conditions was ultimately incorporated into 14CH4. The results demonstrate that, in addition...

A study site underlain by a claypan soil was instrumented to examine the transport of fertilizer nitrogen (N) under corn (Zea mays L.) cultivation. The study was designed to examine N transport within the unsaturated zone and in intedlow (the saturated flow of water on top of the claypan). A 15N-labeled fertilizer (labeled N), bromide (Br), and chloride (Cl) were used as field tracers...