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W. J. Andrews

Publications and source records attributed to W. J. Andrews.

12 recordsLinked to original sources
USGS2000

Water quality in the upper Mississippi River basin, Minnesota, Wisconsin, South Dakota, Iowa, and North Dakota, 1995-98

The report summarizes major findings about water quality in part of the upper Mississippi River basin that emerged from an assessment conducted from 1995 to 1998 by the NAWQA Program. Water quality is discussed in terms of local and regional issues and compared to conditions in the other 36 NAWQA study units assessed to date. Findings are also explained in the context of selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. Finally, this report includes information about the status of aquatic communities and the condition of instream habitat. Many topics covered in the report reflect concerns of officials of State and Federal agencies, water-resource managers, and members of stakeholders groups who provided advice and input during the assessment.

Iowa, Minnesota, North Dakota, South Dakota, Wisco↗
USGS1998

Water-quality assessment of part of the upper Mississippi River basin, Minnesota and Wisconsin— Ground-water quality in an urban part of the Twin Cities Metropolitan area, Minnesota, 1996

In the spring of 1996, the Upper Mississippi River Basin Study Unit of the National Water-Quality Assessment Program drilled 30 shallow monitoring wells in a study area characterized by urban residential and commercial land uses. The monitoring wells were installed in sandy river-terrace deposits adjacent to the Mississippi River in Anoka and Hennepin Counties, Minnesota, in areas where urban development primarily occurred during the past 30 years. Analyses of sediments collected during well drilling indicated that at most well sites the aquifer materials had relatively high hydraulic conductivities (ranging from 0.01 to 238 feet per day), and relatively low organic carbon contents (0.10 to 41 grams per kilogram), indicating a high susceptibility to leaching of fertilizers and organic substances used on the land surface. Sediment pH values, which can affect leaching of pesticides, were generally alkaline, ranging from 5.1 to 9.6. Ground-water levels ranged from 2.39 to 23.14 feet below land surface, and indicated that shallow ground water flows primarily toward the Mississippi River. Dissolved-oxygen concentrations in water samples from the wells were generally less than 3 milligrams per liter (mg/L) and specific conductances were generally greater than 600 microsiemens per centimeter. Calcium, magnesium, sodium, bicarbonate, chloride, and sulfate were the primary dissolved constituents in the water samples. Sodium and chloride concentrations were generally greater than commonly reported in the region, probably due to leaching of sodium chloride applied to roads during the winter. Most tracemetal concentrations in ground-water samples were less than 10 micrograms per liter (μg/L), but concentrations of iron and manganese commonly exceeded Secondary Maximum Contaminant Levels set by the U.S. Environmental Protection Agency of 300 and 50 μg/L, respectively. Mineral saturation indices indicated that calcite, dolomite, and gypsum were slightly undersaturated in most water samples, and that quartz, and many oxides and hydroxides of iron and manganese were oversaturated in all of the water samples. Concentrations of nitrate nitrogen, the primary nutrient of concern in ground water, ranged from less than 0.05 to 16 mg/L, with a median concentration of 1.4 mg/L. Dissolved phosphorus concentrations ranged from less than 0.01 to 1.5 mg/L in the water samples, with a median concentration of 0.02 mg/L. Water from one well was oversaturated with respect to hydroxyapatite, a phosphatic mineral used as a fertilizer. Pesticide compounds were detected in water samples from 16 wells, but concentrations of those compounds were less than 1.0 μg/L. Prometon, an herbicide commonly used for right-of-way weed control, was detected in water samples from 10 of the wells. Atrazine, and its metabolite deethylatrazine, were detectable in water samples from 6 and 8 wells, respectively. Atrazine is commonly applied to land planted with corn and is detectable in rainfall and air samples in concentrations of less than 1 ng/L in the urban land use study area. Other detected pesticide compounds, which are used in agriculture, right-of-way weed control, or lawn care included: tebuthiuron, EPTC, p , p '-DDE, metolachlor, simazine, bentazon, and bromacil. Volatile organic compounds were detected in water samples from 26 wells, but the concentrations of most of those compounds were less than 1 μg/L. Carbon disulfide, which may be produced by bacteria in soils, was the most commonly detected volatile organic compound in water samples from the wells. Other detected volatile organic compounds included: methyl chloride, acetone, dichlorofluoromethane, tetrahydrofuran, trichlorofluoromethane, methyl iodide, 1,1-dichloroethane, chloroform, toluene, trichloroethane, trichloroethene, cis -1,2-dichloroethene, methylene chloride, bromodichloromethane, benzene, methylisobutylketone, ethyl ether, and tetrachloroethene. Tritium concentrations, analyzed in water samples from 15 of the 30 wells, indicated that shallow ground water has been recharged since the mid-1950's, and that shallow ground water should be affected by urban development that has taken place over the past 40 years. Land uses in the urban land use study area affected the concentrations of some water-quality constituents. Concentrations of nitrate and chloride, and frequencies of detection of pesticides and of volatile organic compounds, were greater in water samples from the surficial sand and gravel aquifer underlying the urban land use study area than in water samples from similar aquifers from part of the Upper Mississippi River Basin National Water-Quality Assessment study unit. Land uses within 500-meter radii of each well were quantified by digitizing overlays of aerial photographs that were verified and updated in the field. Concentrations of magnesium and sulfate were greater in ground water beneath areas of denser residential development, which may be a natural artifact of better drainage and a deeper water table in those areas. Frequencies of detection of some pesticides and volatile organic compounds were greater in water from wells with greater proportions of industrial and transportation land uses. Ground water in areas with less dense residential development, mostly the more recently-developed areas, tended to have greater concentrations of agricultural herbicides and some nutrients probably a relict of previous agricultural land use.

Minnesota↗
USGS1998

Water-quality assessment of part of the upper Mississippi River Basin, Minnesota and Wisconsin— Ground-water quality in the Prairie du Chien-Jordan aquifer, 1996

The Prairie du Chien-Jordan (PDCJ) aquifer (Prairie du Chien-Trempealeau aquifer in Wisconsin), composed of dolomite and sandstone of Cambrian to Ordovician age, is the principal bedrock aquifer in the Upper Mississippi River study unit of the National Water-Quality Assessment (NAWQA) Program. The aquifer supplies approximately 75 percent of the ground water withdrawn in the area. In certain areas, the aquifer is overlain by bedrock or glacial deposits having low hydraulic conductivity (termed "confined portion" of the aquifer in this report). In other areas the aquifer is overlain by glacial sand and gravel deposits having greater hydraulic conductivity (termed "unconfined portion" of the aquifer in this report). Differences in the hydrogeologic characteristics of these overlying units have potential to affect the downward movement of water and of contaminants into the aquifer from the land surface. Ground-water samples were collected from 50 domestic wells completed in this aquifer in July, August, and September of 1996 as part of the U.S. Geological Survey's National WaterQuality Assessment Program. The purpose of this report is to describe the chemical characteristics of water in the PDCJ aquifer and to summarize the differences in water quality in confined and unconfined portions of the aquifer. Twenty-five wells were sampled in each portion of the aquifer. Water samples from the wells were measured for physical parameters and analyzed for concentrations of major ions, nutrients, dissolved organic carbon, trace metals, radon, tritium, pesticides, and volatile organic compounds. Differences in anthropogenic and naturally occurring materials in water between confined and unconfined portions of the PDCJ aquifer are small and frequently the differences are not statistically significant at the 95 percent confidence level. Dissolved oxygen concentrations were slightly less and specific conductances and alkalinities were slightly greater in water in the confined portion of the aquifer. Only the differences in specific conductance and alkalinity, however, were statistically significant at the 95 percent confidence level (two sample t-test). Concentrations of most major ions were generally greater in water from the confined portion of the aquifer. Nitrate (nitrite plus nitrate as N) and phosphorus were generally greater in the unconfined portion of the PDCJ aquifer although the differences were not statistically significant at the 95 percent confidence level (nonparametric Mann-Whitney test). In the confined portion of the aquifer no samples exceeded the maximum contaminant level of 10 milligrams per liter for nitrate. In the unconfined portion of the aquifer nitrate in two samples exceeded the maximum contaminant level of 10 milligrams per liter. Phosphorus concentrations were generally about an order of magnitude less than nitrate concentrations. Iron and manganese concentrations commonly exceeded the secondary maximum contaminant levels set by the U.S. Environmental Protection Agency and were generally greater in the confined portion of the PDCJ aquifer, although the differences were not statistically significant at the 95 percent confidence level (nonparametric Mann-Whitney test). Radon concentrations were greater in the confined portion of the aquifer than in the unconfined portion, although the difference was not statistically significant at the 95 percent confidence level (two sample t-test), with medians of 500 and 340 picoCuries per liter, respectively. Sixty-six percent of the radon concentrations were greater than the suspended maximum contaminant level of 300 picoCuries per liter. Tritium concentrations indicate that water in the unconfined portion of the PDCJ aquifer may have been recharged more recently than water in the confined portion of the aquifer, although differences in tritium concentrations between confined and unconfined portions of the aquifer were not statistically significant at the 95 percent confidence level (nonparametric MannWhitney test). Atrazine and its metabolite, deethylatrazine, were the most frequently detected pesticide compounds in water samples from the PDCJ aquifer. Volatile organic compounds were detected in 41 of the 50 water samples, but none of the concentrations exceeded 1 microgram per liter. Concentrations of volatile organic compounds were slightly greater in the unconfined portion, although the differences in detection rates were not statistically significant at the 95 percent confidence level (nonparametric Mann-Whitney test). Carbon disulfide and methyl chloride were the most frequently detected volatile organic compounds. Water in the unconfined portion of the PDCJ aquifer in Minnesota and Wisconsin appears to be affected to a greater degree by anthropogenic activities than water in the confined portion of the aquifer. Water in the confined portion has a longer residence time and greater concentrations of dissolution products of minerals. In general, however, differences in anthropogenic and naturally occurring materials among confined and unconfined portions of the aquifer are small and frequently not significantly different.

Minnesota, Wisconsin↗
USGS1997

Water-quality assessment of part of the upper Mississippi River Basin, Minnesota and Wisconsin — Pesticides in streams, streambed sediment, and ground water, 1974-94

Available data on pesticides in streams, streambed sediment, and ground water from Federal, state, and local agencies are reviewed for part of the Upper Mississippi River Basin study unit of the National Water-Quality Assessment Program. The analysis focuses on a smaller study area encompassing 19,500 square miles that includes the Upper Mississippi River Basin from Lake Pepin upstream to sampling stations on the Mississippi River near Royalton, Minnesota, and the Minnesota River near Jordan, Minnesota, and the entire drainage basins of the St. Croix, Vermillion, and Cannon Rivers. Assessment is generally restricted to two groups of pesticides the most frequently detected herbicides and organochlorine insecticides although pesticides rarely or never detected are noted. Herbicides, including alachlor, atrazine, cyanazine, or metolachlor, were detected in every stream sampled except the Kettle River. Streams draining row-crop areas had the most herbicide detections. Atrazine was the most widely detected herbicide, with detections in all streams sampled except the Kettle River. Concentrations of atrazine, metolachlor, and cyanazine were greatest in July and detectable most of the year at very low (parts-per-trillion) concentrations. The herbicides EPTC and trifluralin were never detected, although they were used in amounts equal to or greater than those detected, reflecting the fact that some herbicides are less persistent than others. A small urban stream draining part of the Lake Harriet Watershed in Minneapolis, Minnesota, contained substantial concentrations of pesticides as well. Eighty-five percent of runoff events sampled in this entirely urbanized watershed had detections of herbicides commonly used for residential purposes, and 43 percent of the events had detections of alachlor, atrazine, cyanazine, or metolachlor herbicides used predominantly for agriculture. Pesticide concentrations in urban runoff remained well above detection limits throughout the summer, indicating repeated applications of pesticides. Selected organochlorine insecticides, banned since the 1970's, still were detected in recent streambed-sediment samples. Three insecticides, 4,4'-DDT, heptachlor, and lindane, and their metabolites account for almost two-thirds of the organochlorine insecticides detected. Organochlorine insecticides were detected more frequently in streambed sediment than in streamwater. Detections in both phases were most frequent within or downstream of the Twin Cities metropolitan area, indicating that most of these insecticides originated from the Twin Cities metropolitan area. The most frequently detected herbicides in ground water were the same as those frequently detected in streams. Most detections were found in the sand and gravel aquifers underlying agricultural areas, including the Anoka Sand Plain and Bonanza Valley. Atrazine, deethylatrazine, and deisopropylatrazine were detected most frequently. Detection frequencies of atrazine were extremely variable among the various agencies, ranging from 0 to 66.7 percent, probably as a result of different sampling purposes, well locations, and detection levels. Atrazine and atrazine metabolites were the only pesticides detected in bedrock aquifers, with detections found mainly in the agriculture-dominated southeastern part of the study area where bedrock commonly outcrops near the surface. Thus, most detections of herbicides in ground water were found in environmental settings where ground water is vulnerable to contamination. Atrazine was the only pesticide that equaled or exceeded a maximum contaminant level (of 3.0 micrograms per liter) for drinking water. Two stream samples from a small urban watershed in Minneapolis had atrazine concentrations of 3.6 and 3.8 micrograms per liter, and one ground-water sample had a concentration of 3.0 micrograms per liter. Trace concentrations (less than 0.06 micrograms per liter) of the organochlorine insecticides chlordane, dieldrin, endrin, and heptachlor exceeded chronic freshwater-quality criteria in stream samples from the Mississippi, Minnesota, St. Croix, and Vemillion Rivers in 1981 and 1990.

Minnesota, Wisconsin↗
USGS1996

Water-quality assessment of part of the Upper Mississippi River basin, Minnesota and Wisconsin: Environmental setting and study design

The Upper Mississippi River Basin is diverse in ways that can control the areal distribution and flow of water and the distribution and concentration of constituents that affect water quality. A review of the environmental setting of the Upper Mississippi River Basin study unit of the National Water-Quality Assessment Program is intended to put water quality in perspective with the geology, soils, climate, hydrology, ecology and historical uses of the land and provides a basis for the sampling design of the study. The Upper Mississippi River Basin study unit encompasses about 47,000 square miles and includes all of the basin upstream from Lake Pepin. The climate of the study unit is subhumid continental with cold dry winters and warm, moist summers. Average annual precipitation ranges from 22 inches in the western part of the study unit to 32 inches in the east. Annual runoff ranges from less than 2 inches in the west to 14 inches in the northeast. The physiography of the study unit includes the Superior Upland and the Central Lowland Provinces. The Wisconsin Driftless Area and the Dissected Till Plains are unique physiographic sections of the Central Lowland Province. Hydrogeologic units in glacial deposits include surficial and buried sand and gravel aquifers and confining units. Bedrock aquifers and confining units are part of a thick sequence of sedimentary rocks that can be divided into major aquifers separated by confining units. The population of the study unit was about 3,640,000 as of 1990 and increased 16 percent between 1970 and 1990. Seventy-five percent of the population lives in the Twin Cities metropolitan area. An average of 413 million gallons of water per day was used 59 percent from ground water and 41 percent from surface water. Land use and land cover in the study unit consists of forested, agricultural, and urban areas. About 63 percent of the land area is agricultural. The quality of water in streams and ground water are affected by both natural and anthropogenic factors. The quality of water is generally satisfactory for most domestic, public, industrial, and irrigation uses. Most water is of the calcium-magnesium-bicarbonate type. The initial six-year phase of the Upper Mississippi River Basin National Water-Quality Assessment, lasting from 1994 to 1999, focuses on data collection and analysis in a 19,500 square-mile area in Minnesota and Wisconsin that includes the Twin Cities metropolitan area. The study design focuses on factors that have an influence on or a potential influence on the water quality in that area. The most significant contaminants include nutrients, pesticides, synthetic-organic compounds, and trace metals. Environmental stratification consists of dividing the study unit into subareas with homogeneous characteristics to assess natural and anthropogenic factors affecting water quality. The assessment of water quality in streams and in aquifers is based on the sampling design that compares water quality within homogeneous subareas defined by subbasins or aquifer boundaries. The study unit is stratified at four levels for the surface-water component: glacial deposit composition, surficial geology, general land use and land cover, and secondary land use. Ground-water studies emphasize shallow ground water where quality is most likely influenced by overlying land use and land cover. Stratification for ground-water sampling is superimposed on the distribution of shallow aquifers. For each aquifer and surface-water basin this stratification forms the basis for the proposed sampling design used in the Upper Mississippi River Basin National Water-Quality Assessment.

Minnesota, Wisconsin↗
USGS1995

Water-quality assessment of part of the Upper Mississippi River Basin, Minnesota and Wisconsin– Volatile organic compounds in surface and ground water, 1978-94

The U.S. Geological Survey compiled and summarized analyses of volatile organic compounds (VOC's) in surface and ground water from water-quality data bases maintained by-Federal, State, and local agencies as part of a retrospective analysis of water-quality data for the Upper Mississippi River Basin study unit of the National WaterQuality Assessment Program. The retrospective analysis focused on a study area that encompasses 19,500 mi 2 of the eastern portion of the study unit. Major river basins in the study area include the part of the Upper Mississippi River drainage from Lake Pepin upstream to sampling stations on the Mississippi and Minnesota Rivers where long-term water-quality data are available and the entire drainage basin of the St. Croix River. The Twin Cities metropolitan area, with a population of 2.4 million people, is located in the south-central part of the study area. Water-quality data collected in the study area from 1978 through 1994 by the U.S. Geological Survey, the Minnesota Department of Health, the Minnesota Pollution Control Agency, the Wisconsin Department of Natural Resources, the Metropolitan Council Environmental Services, and the city of Minneapolis were included in the retrospective analysis. In this report, assessment of the presence and distribution of VOC's in surface and ground water in the study area is restricted to two groups of VOC's: target VOC's, and trihalomethane compounds (THM's). Target VOC's, the most commonly detected non-trihalomethane VOC's in surface and ground water in the study area, include 1,1- dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, trichloroethene, tetrachloroethene, benzene, ethylbenzene, toluene, meta+para-xylene, and ortho-xylene. Trihalomethane compounds described in this report include chloroform, bromodichloromethane, chlorodibromomethane, bromoform, and fluorodichloromethane. Examination of water-quality data from widely distributed sampling networks of river sites and wells in the study area led to the following conclusions: 1) trace amounts of chlorinated VOC's were detected sporadically in waters of the Mississippi, Minnesota, St. Croix, and Vermillion Rivers; 2) benzene, ethylbenzene, toluene, and meta+paraxylene were detected sporadically in waters sampled from the chain of lakes used as the municipal supply for St. Paul, Minnesota; 3) the target VOC's were detected in less than five percent of ground-water samples at relatively low concentrations, generally near detection limits which ranged from 1 to 5 micrograms per liter; 4) VOC's were generally detected at similar frequencies, but at higher concentrations, in water samples from wells completed in sand and gravel aquifers than in water samples from wells completed in bedrock aquifers; 5) VOC's were most commonly detected in ground water in the vicinity of identifiable emission sites of VOC's, such as landfills, dumps, or major industries; 6) trichloroethene, a commonly used degreasing agent in dry cleaning, metal cleaning and cleaning septic lines, was the most frequently detected target VOC in ground water sampled from wells completed in both sand and gravel and bedrock aquifers; 7) wells producing water with detectable concentrations of the target VOC's tended to be shallower than wells producing water with no detectable concentrations of those compounds, but the differences in well depths were not statistically significant at a 95 percent confidence level; and 8) chlorination of water substantially increased the frequency of detection of trihalomethane compounds. The low frequencies of detection of the target VOC's and THM's in surface and ground water sampled from widely distributed sampling networks in the study area indicate that, although there are thousands of sites which can potentially emit these compounds to water, soil, and the atmosphere, these compounds have not had a widespread measurable effect on the quality of surface and ground water in the study area.

Minnesota, Wisconsin↗
USGS1994

Ground-water quality and trends at two industrial wastewater-injection sites in northwestern Florida, 1975-91

Industrial wastewater from two synthetic-fiber manufacturing plants has been injected into the Lower Floridan aquifer near Pensacola, Florida, since 1963, and near Milton, Florida, since 1975. Trend analysis of selected water-quality characteristics in water from four monitoring wells at each of these plants indicates that injected wastewater has affected ground-water quality in the Lower Floridan aquifer, which contains nonpotable water, up to 1.5 miles from the injection wells at the plant near Pensacola and at least 0.3 mile from the injection wells at the plant near Milton. No evidence for upward seepage of injected wastewater through the overlying Bucatunna Clay to the Upper Floridan aquifer was found at either of the plants.

Florida↗
USGS1994

Nitrate in ground water and spring water near four dairy farms in North Florida, 1990-93

Concentrations of nitrate and other selected water- quality characteristics were analyzed periodically for two years in water from 51 monitoring wells installed at four farms and in water discharging from three nearby springs along the Suwannee River in Lafayette and Suwannee Counties to examine the quality of ground water at these farms and the transport of nutrients in ground water to the nearby spring-fed Suwannee River: Ground water from shallow wells, which were completed in the top ten feet of the saturated zone in a surficial sandy aquifer and in the karstic Upper Floridan aquifer generally had the highest concentrations of nitrate, ranging from <.02 to 130 mg/L as nitrogen. Nitrate concentrations commonly exceeded the primary drinking water standard of 10 mg/L for nitrate as nitrogen in water from shallow wells, which tapped the top ten feet of the uppermost aquifers near waste-disposal areas such as wastewater lagoons and defoliated, intensive-use areas near milking barns. Upgradient from waste-disposal areas, concentrations of nitrate in ground water were commonly less than 1 mg/L as nitrogen. Water samples from deep wells (screened 20 feet deeper than shallow wells in these aquifers) generally had lower concentrations of nitrate (ranging from <0.02 to 84 mg/L) than water from shallow wells. Water samples from the three monitored springs (Blue, Telford, and Convict Springs) had nitrate concentrations ranging from 1.5 to 6.5 mg/L as nitrogen, which were higher than those typically occurring in water from upgradient wells at the monitored dairy farms or from back- ground wells sampled in the region. Analyses of nitrogen isotope ratios in nitrate indicated that leachate from animal wastes was the principal source of nitrate in ground water adjacent to waste-disposal areas at the monitored and unmonitored dairy farms. Leachate from a combi- nation of fertilizers, soils, and animal wastes appeared to be the source of nitrate in ground- water downgradient from pastures and wastewater spray fields at dairy farms and in water discharging from three nearby springs. Although denitrifying bacteria were present in counts sometimes exceeding 240,000 colonies/100mL in water from dairy-farm monitoring wells, ground water in the uppermost aquifers in Lafayette and Suwannee Counties generally contained too much oxygen for denitrification to remove nitrate from shallow ground water. Denitrification was more likely to occur in deeper ground water, which typically has lower dissolved oxygen concentrations.

Florida↗