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D.B. Chambers

Publications and source records attributed to D.B. Chambers.

5 recordsLinked to original sources
USGS2007

Semipermeable membrane devices used to estimate bioconcentration of polychlorinated biphenyls

ABSTRACT: Aquatic organisms passively accumulate hydrophobic organic compounds, such as polychlorinated biphenyls, even when ambient water concentrations of the contaminant are below analytical detection limits. However, contaminant concentrations in tissue samples are subject to an inherently high level of variability due to differences in species, life stage, and gender bioconcentration potentials. Semipermeable membrane devices (SPMDs) were used to sample Aroclor 1254, a mixture of readily bioconcentrated polychlorinated biphenyls (PCBs), in a contaminated wetland near Flat Top, WV. The devices consisted of triolein, a lipid found in fish, enclosed in a polyethylene membrane. SPMDs were deployed in the water column and in direct contact with wetland sediments along a previously identified concentration gradient of PCBs. The devices were retrieved after a 25-day exposure period. Analytes were recovered by dialyzing the devices in nanograde hexane. Hexane dialysates were condensed and analyzed by gas chromatography. All deployed devices sequestered quantifiable amounts of Aroclor 1254. Water-column SPMDs accumulated PCBs far in excess of ambient water concentrations. The devices contacting sediments accumulated PCBs at all sites, though accumulated concentrations did not exceed concentrations in sediment. Patterns of PCB concentration in the devices corresponded to the identified gradient at the site. Results from the water-column SPMDs were used to estimate the concentration of the dissolved, bioavailable fraction of PCBs present in the water column. These concentrations ranged from 0.01 to 0.09 μg/L of bioavailable Aroclor 1254.

Journal of the American Water Resources Associatio↗
USGS1996

Physical, chemical, and biological data for four wetland habitats in Canaan Valley, West Virginia

This report contains data collected during 1992 as part of a project designed to identify microenvironmental factors affecting rates of denitrification in wetlands in Canaan Valley, West Virginia. Four wetland habitats were selected for the study--a moss-lichen wetland, a persistent emergent wetland, a scrub-shrub wetland, and a riverine wetland. Physical, chemical, and biological characteristics of each habitat were determined by field measurements and laboratory analyses. Samples were collected in March, June, August, and October. Sediment pH, temperature, and oxidation-reduction potential were measured in the field. Sediment samples were analyzed for concentrations of calcium, sodium, magnesium, potassium, nitrate and nitrite, ammonia, ammonia plus organic nitrogen, phosphorus, inorganic carbon, and total carbon. The most probable number of denitrifying bacteria was determined by a multiple-tube test. The dominant plant species were identified by plant-community analysis. The moss-lichen wetland was characterized by low pH (3.4 to 5.0) and small populations of denitrifying bacteria (70 to 400 per gram of wet soil). The scrub-shrub wetland was also acidic (pH 4.0 to 5.0), but supported larger numbers of denitrifying bacteria (510 to 11,000 per gram of wet soil). The number of denitrifying bacteria in the persistent emergent wetland exceeded 1,000,000 per gram of wet soil in early summer and pH in this habitat was higher (5.1 to 6.6) than in the bogs. Riverine wetland pH ranged from 5.4 to 6.9, and the number of denitrifying bacteria ranged from 200 to 11,000 per gram of wet soil.

Open-File Report↗
USGS1995

Water-quality data for the Ohio River from New Cumberland Dam to Pike Island Dam, West Virginia and Ohio, June-November 1992

This report contains water-quality data for the Ohio River, collected during the summer and fall of 1992, from river mile 51.1 (3.3 miles upstream from New Cumberland Dam) to river mile 84.0 (0.2 miles upstream from Pike Island Dam). The data were collected to assess the effects of hydropower development on water quality. Water quality was determined by a combination of repeated synoptic field measurements and laboratory analyses. Synoptic measurements were made along a longitudinal transect with 18 mid-channel sampling sites; cross-sectional transects of water quality were measured at 5 of these sites. Water-quality measurements also were made at two sites located on the back-channel (Ohio) side of Browns Island. Water temperature, dissolved oxygen concentration, pH, and specific conductance were measured at each longitudinal-transect and back-channel sampling site. Longitudinal-transect and back-channel stations were sampled at three depths (about 3.3 feet below the surface of the water, middle of the water column, and near the bottom of the river). Cross-sectional transects consisted of three or four detailed vertical pro- files of the same characteristics. Water samples were collected from three depths at the mid-channel vertical profile in each cross-sectional transect and were analyzed for concentrations of phyto- plankton photosynthetic pigments chlorophyll a and chlorophyll b. Estimates of the depth of light penetration (Secchi disk transparency) were made at pigment-sampling locations whenever light and river-surface conditions were appropriate. Synoptic sampling usually was completed in 12 hours or less and was repeated seven times between June 25 and November 6, 1992.

Open-File Report↗
USGS1994

Water-quality data for the Ohio River from Willow Island Dam to Belleville Dam, West Virginia and Ohio, June-October 1991

This report contains water-quality data for the Ohio River from river mile 160.6 (1.1 mi upstream from Willow Island Dam) to river mile 203.6 (0.3 mi upstream from Belleville Dam) during the summer of 1991. Water quality was determined by a combi- nation of synoptic field measurements and laboratory analyses. Synoptic sampling consisted of 8 cross-sectional transects and a longitudinal transect with 28 mid-channel stations. Each cross- sectional transect included five vertical profiles of water temperature, dissolved oxygen concen- tration, pH, and specific conductance. Longi- tudinal transect stations were sampled at three depths (near the surface, middle of the water column, and at or near the bottom) for the same characteristics. Sampling was completed in 3 days or less, and was repeated approximately every 2 weeks from June through October 1991. Beginning in August 1991, water samples were collected at selected locations and analyzed for chlorophyll-a and pheophytin concentrations, as measures of phytoplankton biomass and phytoplankton-degradation products, respectively. The depth of light penetration was estimated at all pigment-sampling locations.

Open-File Report↗