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A.C. Ziegler

Publications and source records attributed to A.C. Ziegler.

8 recordsLinked to original sources
USGS2006

The legacy of leaded gasoline in bottom sediment of small rural reservoirs

The historical and ongoing lead (Pb) contamination caused by the 20th-century use of leaded gasoline was investigated by an analysis of bottom sediment in eight small rural reservoirs in eastern Kansas, USA. For the reservoirs that were completed before or during the period of maximum Pb emissions from vehicles (i.e., the 1940s through the early 1980s) and that had a major highway in the basin, increased Pb concentrations reflected the pattern of historical leaded gasoline use. For at least some of these reservoirs, residual Pb is still being delivered from the basins. There was no evidence of increased Pb deposition for the reservoirs completed after the period of peak Pb emissions and (or) located in relatively remote areas with little or no highway traffic. Results indicated that several factors affected the magnitude and variability of Pb concentrations in reservoir sediment including traffic volume, reservoir age, and basin size. The increased Pb concentrations at four reservoirs exceeded the U.S. Environmental Protection Agency threshold-effects level (30.2 mg kg-1) and frequently exceeded a consensus-based threshold-effects concentration (35.8 mg kg-1) for possible adverse biological effects. For two reservoirs it was estimated that it will take at least 20 to 70 yr for Pb in the newly deposited sediment to return to baseline (pre-1920s) concentrations (30 mg kg-1) following the phase out of leaded gasoline. The buried sediment with elevated Pb concentrations may pose a future environmental concern if the reservoirs are dredged, the dams are removed, or the dams fail. ?? ASA, CSSA, SSSA.

Journal of Environmental Quality↗
USGS2002

Method of analysis and quality-assurance practices by the U.S. Geological Survey Organic Geochemistry Research Group: Determination of geosmin and methylisoborneol in water using solid-phase microextraction and gas chromatography/mass spectrometry

A method for the determination of two common odor-causing compounds in water, geosmin and 2-methylisoborneol, was modified and verified by the U.S. Geological Survey's Organic Geochemistry Research Group in Lawrence, Kansas. The optimized method involves the extraction of odor-causing compounds from filtered water samples using a divinylbenzene-carboxen-polydimethylsiloxane cross-link coated solid-phase microextraction (SPME) fiber. Detection of the compounds is accomplished using capillary-column gas chromatography/mass spectrometry (GC/MS). Precision and accuracy were demonstrated using reagent-water, surface-water, and ground-water samples. The mean accuracies as percentages of the true compound concentrations from water samples spiked at 10 and 35 nanograms per liter ranged from 60 to 123 percent for geosmin and from 90 to 96 percent for 2-methylisoborneol. Method detection limits were 1.9 nanograms per liter for geosmin and 2.0 nanograms per liter for 2-methylisoborneol in 45-milliliter samples. Typically, concentrations of 30 and 10 nanograms per liter of geosmin and 2-methylisoborneol, respectively, can be detected by the general public. The calibration range for the method is equivalent to concentrations from 5 to 100 nanograms per liter without dilution. The method is valuable for acquiring information about the production and fate of these odor-causing compounds in water.

Open-File Report↗
USGS2002

Real-time water quality monitoring and regression analysis to estimate nutrient and bacteria concentrations in Kansas streams

An innovative approach currently is underway in Kansas to estimate and monitoring constituent concentrations in streams. Continuous in-stream water-quality monitors are installed at selected U.S. Geological Survey stream-gaging stations to provide real-time measurement of specific conductance, pH, water temperature, dissolved oxygen, turbidity, and total chlorophyll. In addition, periodic water samples are collected manually and analyzed for nutrients, bacteria, and other constituents of concern. Regression equations then are developed from measurements made by the water-quality monitors and analytical results of manually collected samples. These regression equations are used to estimate nutrient, bacteria, and other constituent concentrations. Concentrations then are available to calculate loads and yields to further assess water quality in watersheds. The continuous and real-time nature of the data may be important when considering recreational use of a water body; developing and monitoring total maximum daily loads; adjusting water-treatment strategies; and determining high constituent concentrations in time to prevent adverse effects on fish or other aquatic life.

Conference Paper↗
USGS1997

Baseline data-collection and quality-control protocols and procedures for the Equus beds ground-water recharge demonstration project near Wichita, Kansas, 1995-96

The Equus Beds Ground-Water Recharge Demonstration Project is being conducted from 1995 through 1999 as part of the High Plains States Groundwater Recharge Demonstration Program to determine if recharge of the Equus beds aquifer in south-central Kansas is a viable alternative in meeting the increased demands for water in this rapidly growing part of the State. As part of the demonstration project, protocols and procedures were developed for the collection of baseline hydrologic and water-quality data from September 1995 through September 1996 and are described in this report. During this initial phase of the demonstration project, 33 data-collection sites were identified and instrumented, and an aquifer test at one site was conducted to determine transmissivity, specific yield, hydraulic conductivity, and riverbed conductance of the Equus beds aquifer in the area northwest of Wichita, Kansas. Selected water-quality samples were analyzed for as many as 340 chemical constituents to determine the baseline or ambient concentrations of inorganic and orgainc constituents.

Open-File Report↗
USGS1995

Water-quality conditions of inflow, outflow, and impounded water at Rathbun Reservoir, Iowa, Clinton and Pomona Lakes, Kansas, and Harlan County Reservoir, Nebraska, May through August 1993

During May through August 1993, water-quality samples were collected twice from selected sites in Rathbun Reservoir, Iowa, Clinton and Pomona Lakes, Kansas, and Harlan County Reservoir, Nebraska. Samples were analyzed for selected physical and chemical properties, bacteria, major ions, nutrients, selected metals, total organic carbon, selected herbicides, and chlorophyll-a and -b. During May through August 1993, precipitation at all four reservoirs exceeded mean precipitation at nearby long-term precipitation gages; precipitation ranged from 7.76 inches above the long-term mean at Pomona Lake to 12.62 inches above the long-term mean at Rathbun Reservoir. Reservoir water-surface elevations exceeded flood-pool elevation by 4 feet in Clinton Lake, by 19 feet in Pomona Lake, and by 2 feet in Harlan County Reservoir in July. Thermal stratification of water occurred at one site in Rathbun Reservoir in August, at two sites in Clinton Lake in May, at one site in Pomona Lake in June, and at one site in Harlan County Reservoir in June. Total triazine herbicide concentrations in water samples from all four reservoirs ranged from 0.2 to 19 micrograms per liter and were largest water samples from Rathbun Reservoir in June. Concen- trations of atrazine exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level of 3.0 micrograms per liter for drinking water in at least one sample each from Rathbun Reservoir, Clinton Lake, and Pomona Lake. Concentrations of cyanazine exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level of 1.0 microgram per liter in water samples from Rathbun Reservoir.

Open-File Report↗