Geology topics

K.D. Richards

Publications and source records attributed to K.D. Richards.

4 recordsLinked to original sources

USGS2010

A fresh look at road salt: Aquatic toxicity and water-quality impacts on local, regional, and national scales

A new perspective on the severity of aquatic toxicity impact of road salt was gained by a focused research effort directed at winter runoff periods. Dramatic impacts were observed on local, regional, and national scales. Locally, samples from 7 of 13 Milwaukee, Wisconsin area streams exhibited toxicity in Ceriodaphnia dubia and Pimephales promelas bioassays during road-salt runoff. Another Milwaukee stream was sampled from 1996 to 2008 with 72% of 37 samples exhibiting toxicity in chronic bioassays and 43% in acute bioassays. The maximum chloride concentration was 7730 mg/L. Regionally, in southeast Wisconsin, continuous specific conductance was monitored as a chloride surrogate in 11 watersheds with urban land use from 6.0 to 100%. Elevated specific conductance was observed between November and April at all sites, with continuing effects between May and October at sites with the highest specific conductance. Specific conductance was measured as high as 30 800 ??S/cm (Cl = 11 200 mg/L). Chloride concentrations exceeded U.S. Environmental Protection Agency (USEPA) acute (860 mg/L) and chronic (230 mg/L) water-quality criteria at 55 and 100% of monitored sites, respectively. Nationally, U.S. Geological Survey historical data were examined for 13 northern and 4 southern metropolitan areas. Chloride concentrations exceeded USEPA water-quality criteria at 55% (chronic) and 25% (acute) of the 168 monitoring locations in northern metropolitan areas from November to April. Only 16% (chronic) and 1% (acute) of sites exceeded criteria from May to October. At southern sites, very few samples exceeded chronic water-quality criteria, and no samples exceeded acute criteria. ?? 2010 American Chemical Society.

Environmental Science & Technology↗

USGS2000

Beryllium-7 as a tracer of short-term sediment deposition and resuspension in the Fox River Wisconsin

Short-term (∼monthly) sediment deposition and resuspension rates of surficial bed sediments in two PCB-laden impoundments on the Fox River, WI, were determined in the summer and fall of 1998 using 7 Be, a naturally occurring radioisotope produced in the atmosphere. Decay-corrected activities and inventories of 7 Be were measured in bed sediment and in suspended particles. Beryllium-7 activities generally decreased with depth in the top 5−10 cm of sediments and ranged from undetectable to ∼0.9 pCi cm - 3 . Inventories of 7 Be, calculated from the sum of activities from all depths, ranged from 0.87 to 3.74 pCi cm - 2 , and the values covaried between sites likely reflecting a common atmospheric input signal. Activities of 7 Be did not correlate directly with rainfall. Partitioning the 7 Be flux into “new” and “residual” components indicated that net deposition was occurring most of the time during the summer. Net erosion, however, was observed at the upstream site from the final collection in the fall. This erosion event was estimated to have removed 0.10 g (cm of sediment) - 2 , corresponding to ∼0.5 cm of sediment depth, and ∼6−10 kg of polychlorinated biphenyls (PCBs) over the whole deposit. Short-term accumulation rates were up to ∼130 times higher than the long-term rates calculated from 137 Cs profiles, suggesting an extremely dynamic sediment transport environment, even within an impounded river system.

Environmental Science & Technology↗

USGS1998

Surface-water quality at fixed sites in the Western Lake Michigan Drainages, Wisconsin and Michigan, and the effects of natural and human factors, 1993-95

Streamwater samples were collected from April 1993 through July 1995 at 11 fixed sites in the Western Lake Michigan Drainages Study Unit of the U.S. Geological Survey's National Water-Quality Assessment Program. Water samples were collected monthly at all Fixed Sites, and an additional two to four samples were collected each year during periods of high flow. Streamflow was monitored continuously at the Fixed Sites for the duration of the study period. This report describes field techniques used to collect the water samples, and the analytical methods used for laboratory analyses, statistical analyses of the data, and an attempt to determine the effect of natural and anthropogenic factors on concentrations of nutrients and selected major ions and suspended solids. Locations of eight of the Fixed Sites were selected to represent areas with unique combinations of land use/land cover, surficial deposits, and bedrock geology and are referred to as 'indicator sites.' The remaining three sites were located near the mouths of major rivers and are referred to as 'integrator sites.' The integrator sites represent a large part of the total flow from the Study Unit to Green Bay and western Lake Michigan, and drain various combinations of land use, bedrock, and surficial deposits. These data indicate that land use and surficial deposits may be the primary factors affecting nitrate and total phosphorus concentrations in this Study Unit. Median concentrations of nitrate at the forested sites were less than the National Median Concentration (NMC), and those at urban fixed sites were similar to the NMC. Median nitrate concentrations at the Tomorrow River, North Branch Milwaukee River, and Duck Creek agricultural indicator sites were twice the NMC, but median concentrations at the remaining agricultural indicator sites were similar to the NMC. Nitrate concentrations at one agricultural indicator site exceeded the U. S. Environmental Protection Agency (USEPA) maximum contaminant level in three run-off samples in the growing seasons of 1994 and 1995. Median concentrations of total phosphorus at the forested indicator sites were below the NMC. Tomorrow River was the only agricultural indicator site where the median total-phosphorus concentration was less than the NMC; median concentrations at the remaining agricultural Fixed Sites were similar to the NMC and exceeded 0.1 mg/L, the USEPA suggested total-phosphorus concentration in flowing water. The USEPA recommends that total-phosphorus concentration not exceed this limit to discourage excessive aquatic plant growth in flowing waters. Median total-phosphorus concentration at the urban indicator site was less than the urban NMC. Median concentrations for both nitrate and total phosphorus at the mouth of the Fox River and the Milwaukee River integrator sites were similar to the NMC for the dominant land use, agriculture, within their basins, and were lower than that at the Menominee River integrator site with a dominant forest land use. During this study, potassium concentrations were generally highest in areas of clay-dominated surficial deposits, silica was generally highest in areas of sandy surficial deposits, iron generally highest in areas of igneous/metamorphic bedrock, and calcium generally highest in areas of carbonate bedrock. The highest median fluoride concentration occurred at an urban site that receives treated water.

Michigan, Wisconsin↗

USGS1995

Environmental setting of fixed sites in the western Lake Michigan drainages, Michigan and Wisconsin

This report describes selected environmental- setting features for 11 fixed surface-water sites in the Western Lake Michigan Drainages study unit of the National Water-Quality Assessment Pro- gram. The study unit, which includes 10 major river systems draining to Lake Michigan, is bounded on the south by the Illinois State line and extends north to about 31 miles north of Escanaba, Mich. The fixed sites are on the following streams: Peshekee River, Popple River, Menominee River, Pensaukee River, Duck Creek, Tomorrow River, East River, Fox River, North Branch Milwaukee River, Lincoln Creek, and Milwaukee River. Drainage basins above these sites receive runoff from land uses and land covers, bedrock types, and surficial deposits representative of the main types of each of these characteristics in the study unit. Data types collected at the fixed sites include water chemistry; organic compounds and trace elements in streambed sediment and biological tissues; algal, benthic-invertebrate, and fish communities; and aquatic habitat. Field measurements include water temperature, pH, specific conductance, alkalinity, and dissolved oxygen. Results of water- quality field measurements indicate little variation in temperature among the fixed sites. Specific conductance and alkalinity were generally higher at sites underlain by carbonate bedrock than at sites underlain by igneous/metamorphic bedrock. Differences in pH among the fixed sites were less than those for specific conductance and alkalinity, but pH seemed to increase slightly from north to south. Dissolved-oxygen concentration varied more at agricultural sites than at forested and urban sites, perhaps because of higher nutrient inputs at agricultural sites. The information included in this report has been assembled as reference material for ongoing studies at the fixed sites.

Water-Resources Investigations Report↗