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William J. Andrews

Publications and source records attributed to William J. Andrews.

46 records · Page 3Linked to original sources

Ground-water quality in the central High Plains aquifer, Colorado, Kansas, New Mexico, Oklahoma, and Texas, 1999

A network of 74 randomly distributed domestic water-supply wells completed in the central High Plains aquifer was sampled and analyzed from April to August 1999 as part of the High Plains Regional Ground-Water Study conducted by the U. S. Geological Survey National Water-Quality Assessment Program to provide a broad-scale assessment of the ground-water-quality in this part of the High Plains aquifer. Water properties were relatively consistent across the aquifer, with water being alkaline and well oxidized. Water was mostly of the calcium and magnesium-bicarbonate type and very hard. Sulfate concentrations in water from three wells and chloride concentration in water from one well exceeded Secondary Maximum Contaminant Levels. Fluoride concentration was equal to the Maximum Contaminant Level in one sample. Nitrate concentrations was relatively small in most samples, with the median concentration of 2.3 milligrams per liter. Dissolved organic carbon concentration was relatively low, with a median concentration of 0.5 milligram per liter. The Maximum Contaminant Level set by the U.S. Environmental Protection Agency for nitrate as nitrogen of 10 milligrams per liter was exceeded by water samples from three wells. Most samples contained detectable concentrations of the trace elements aluminum, arsenic, barium, chromium, molybdenum, selenium, zinc, and uranium. Only a few samples had trace element concentrations exceeding Maximum Contaminant Levels. Fifty-five of the samples had radon concentrations exceeding the proposed Maximum Contaminant Level of 300 picocuries per liter. The greatest radon concentrations were detected where the Ogallala Formation overlies sandstones, shales and limestones of Triassic, Jurassic, or Cretaceous age. Volatile organic compounds were detected in 9 of 74 samples. Toluene was detected in eight of those nine samples. All volatile organic compound concentrations were substantially less than Maximum Contaminant Levels. Detections of toluene may have been artifacts of the sampling and analytical processes. Pesticides were detected in 18 of the 74 water samples. None of the pesticide concentrations exceeded Maximum Contaminant Levels. The most frequently detected pesticides were atrazine and its metabolite deethylatrazine, which were detected in water from 15 and 17 wells, respectively. Most of the samples with a detectable pesticide had at least two detectable pesticides. Six of the samples had more than two detectable pesticides. Tritium concentrations was greater than 0.5 tritium unit in 10 of 51 samples, indicating recent recharge to the aquifer. Twenty-one of the samples that had nitrate concentrations greater than 4.0 milligrams per liter were assumed to have components of recent recharge. Detection of volatile organic compounds was not associated with those indicators of recent recharge, with most of volatile organic compounds being detected in water from wells with small tritium and nitrate concentrations. Detection of pesticides was associated with greater tritium or nitrate concentrations, with 16 of the 18 wells producing water with pesticides also having tritium or nitrate concentrations indicating recent recharge.

Colorado, Kansas, New Mexico, Oklahoma, Texas↗

Relation of shallow water quality in the Central Oklahoma Aquifer to geology, soils, and land use

The purpose of this report is to identify, describe, and explain relations between natural and land-use factors and ground-water quality in the Central Oklahoma aquifer NAWQA study unit. Natural factors compared to water quality included the geologic unit in which the sampled wells were completed and the properties of soils in the areas surrounding the wells. Land-use factors included types of land use and population densities surrounding sampled wells. Ground-water quality was characterized by concentrations of inorganic constituents, and by frequencies of detection of volatile organic compounds and pesticides. Water-quality data were from samples collected from wells 91 meters (300 feet) or less in depth as part of Permian and Quaternary geologic unit survey networks and from an urban survey network. Concentrations of many inorganic constituents were significantly related to geology. In addition, concentrations of many inorganic constituents were greater in water from wells from the Oklahoma City urban sampling network than in water from wells from low-density survey networks designed to evaluate ambient water quality in the Central Oklahoma aquifer study unit. However, sampling bias may have been induced by differences in hydrogeologic factors between sampling networks, limiting the ability to determine land-use effects on concentrations of inorganic constituents. Frequencies of detection of pesticide and volatile organic compounds (VOC's) in ground-water samples were related to land use and population density, with these compounds being more frequently detected in densely-populated areas. Geology and soil properties were not significantly correlated to pesticide or VOC occurrence in ground water. Lesser frequencies of detection of pesticides in water from wells in rural areas may be due to low to moderate use of those compounds on agricultural lands in the study unit, with livestock production being the primary agricultural activity. There are many possible sources of pesticides and VOC's in the urban areas of Central Oklahoma. Because only existing water-supply wells were sampled, it is not clear from the data collected whether pesticides and VOC's: (1) occur in low concentrations throughout upper portions of the aquifer in urban areas, or (2) are present in ground water only in the immediate vicinity of the wells due to back-flow of those chemicals into the wells or to inflow around cement seals and through gravel packs surrounding well casings of surface runoff containing those compounds.

Oklahoma↗

Water flow in the high plains aquifer in Northwestern Oklahoma

The High Plains is a major agricultural area, supported primarily by water from the High Plains aquifer, which is used to irrigate wheat and corn and to raise cattle and swine. The U.S. Geological Survey (USGS) and the Oklahoma Water Resources Board (OWRB) began a study of the High Plains aquifer in 1996. One purpose of the study was to develop a ground-water flow model that the OWRB could use to allocate the amount of water withdrawn from the a aquifer. The study area in Oklahoma covers all or parts of Beaver, Cimarron, Dewey, Ellis, Harper, Texas, and Woodward Counties. To provide appropriate hydrologic boundaries for the ground-water flow model, the study area was expanded to include parts of Colorado, Kansas, New Mexico, and Texas.

Oklahoma↗

Rapid recharge of parts of the high plains aquifer indicated by a reconnaissance study in Oklahoma, 1999

The High Plains aquifer underlies about 174,000 square miles in parts of eight states, including about 7,100 square miles in northwestern Oklahoma (fig. 1). This aquifer consists of the saturated part of the Ogallala Formation and saturated materials of Quaternary Age that are hydraulically connected to the Ogallala. The High Plains aquifer in northwestern Oklahoma is the primary source of water to an important agricultural region. Most water is withdrawn from the aquifer for irrigating wheat and other grain crops, with the remainder used for livestock (primarily cattle and swine), municipal, and domestic needs. Historically, water from precipitation was thought to take hundreds or thousands of years to reach the water table because the depth of the water table is greater than 100 feet over most of the aquifer and the low-permeability beds in the Ogallala would impede downward flow. It also was thought that land uses would take a similar period of time to affect water quality in the aquifer.

Oklahoma↗

Water-quality assessment of part of the Upper Mississippi River Basin, Minnesota and Wisconsin - Ground-water quality in an agricultural area of Sherburne County, Minnesota, 1998

The quality of shallow ground water in a 75-mi 2 agricultural area of the Anoka Sand Plain aquifer in central Minnesota is described as part of the National Water Quality Assessment (NAWQA) Program - a national-scale assessment of the quality of water resources within large study units in various hydrologic settings. Data were collected during 1998 from 29 wells completed in the aquifer, which predominantly consists of surficial glacial sand and gravel sediments. The depth below land surface to the water table ranged from 3.3 to 44 ft (median of 15.5 ft). Ground water was of the calciummagnesium bicarbonate type. Ionic constituents also included sodium, sulfate, and chloride. Iron and manganese concentrations generally were not greater than their U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Levels (300 and 50 ug/L, respectively). About 38 percent of 29 samples had nitrate-N (nitrogen) concentrations greater than the USEPA Maximum Contaminant Level (MCL) of 10 mg/L. About 72 percent of the samples had nitrate-N concentrations greater than the presumed natural background level of 3 mg/L. The maximum nitrate-N concentration was 47 mg/L. The median nitrate-N concentration of 7.1 mg/L, although not greater than the MCL, exceeded the natural background level. Nitrogen isotope ratios indicate that the sources of nitrate were commercial fertilizer and soil organic matter. Concentrations of total dissolved phosphorus and orthophosphate were generally less than 1 mg/L. About 86 percent of 29 samples had detectable concentrations of at least 1 of 13 pesticide compounds. The samples were analyzed for 83 pesticide compounds. Frequencies of detection of these compounds were: deethylatrazine-79 percent; atrazine-76 percent; metolachlor-41 percent; metribuzin and bentazon-21 percent; prometon-10 percent; tebuthiuron-7 percent; and alachlor, 2,6-diethylaniline, dicamba, dinoseb, malathion, and simazine-3 percent. The detected pesticide compounds had concentrations less than 1 ug/L. Detected compounds with USEPA MCLs (atrazine, bentazon, alachlor, dinoseb, and simazine) had concentrations less than their respective MCLs. About 50 percent of 20 samples analyzed for 86 volatile organic compounds (VOCs) had detectable concentrations of at least 1 of 7 VOCs. Frequencies of detection of these 7 VOCs were: 1,2,3,4-tetramethylbenzene-40 percent; and trichlorofluoromethane, styrene, chloromethane, benzene, methylbenzene, and trichloromethane-5 percent. The detected VOCs had concentrations less than 0.120 ug/L. Detected VOCs with USEPA MCLs - styrene, benzene, methylbenzene, and trichloromethane - were present at concentrations 2-4 orders of magnitude less than their respective MCLs. Tritium concentrations had a range of from 7.5 to 18.8 tritium units (TUs) and a median of 12.5 TUs. These concentrations indicate that the ground water predominantly recharged after testing of thermonuclear weapons during the early 1950's.

Minnesota↗

Water-quality assessment of part of the upper Mississippi River Basin, Minnesota and Wisconsin — Nitrogen and phosphorus in streams, streambed sediment, and ground water, 1971-94

Nitrogen and phosphorus in streams, streambed sediment, and ground water were summarized using data from Federal, state, and local agencies as part of an analysis of historical water-quality data for the Upper Mississippi River Basin study unit of the U.S. Geological Survey's National Water-Quality Assessment Program. The Upper Mississippi River Basin study unit encompasses the drainage of the Mississippi River from the source to the outlet of Lake Pepin. This report focuses on a 19,500-square-mile study area in the eastern part of the study unit. The study area included the part of the Upper Mississippi River Basin from Royalton, Minnesota, to the outlet of Lake Pepin, located near Red Wing, Minnesota; the Minnesota River Basin from Jordan, Minnesota, to the confluence with the Mississippi River; and the entire drainage basins of the St. Croix, Cannon, and Vermillion Rivers. The Twin Cities metropolitan area, with a population of approximately 2.3 million people, is located in the south-central part of the study area. Fertilizers and livestock manure were the greatest sources of nitrogen and phosphorus applied to the land surface of the study unit. Approximately 60 percent of the fertilizer was applied to the Minnesota River Basin, which drains agricultural areas in the southern and western parts of the study unit. Concentrations of total nitrite plus nitrate nitrogen, total nitrogen, and total phosphorus in streams, generally were greatest in the tributaries to the Mississippi River draining agricultural areas in the western and southern part of the study area. Concentrations of these constituents generally were least in tributaries draining forested land. The greatest total nitrite plus nitrate nitrogen concentrations generally occurred during the spring and summer in streams draining agricultural areas and in the winter in streams draining forested areas. Total phosphorus concentrations generally were greatest in the spring and summer for all streams. Total nitrite plus nitrate nitrogen, total nitrogen, and total phosphorus concentrations in the Mississippi River increased substantially downstream from the Minnesota River and downstream from wastewater discharges in the Twin Cities metropolitan area. Total ammonia and dissolved orthophosphate concentrations generally were greatest at sites on the Mississippi and Minnesota Rivers downstream from wastewater discharges from the Twin Cities metropolitan area. Total nitrite plus nitrate nitrogen concentrations in streams generally were less than the Maximum Contaminant Level of 10 mg/L (as nitrogen) established by the U.S. Environmental Protection Agency. Total phosphorus concentrations in streams generally were greater than the 0.1 mg/L concentration recommended by the U.S. Environmental Protection Agency at sites located in agricultural areas and on the Mississippi River downstream from its confluence with the Minnesota River. Phosphorus and nitrogen yields were greatest in watersheds primarily draining agricultural land. The majority of the nitrogen and phosphorus loading to the Mississippi River was from the Minnesota River. In the Minnesota River, the nitrogen load primarily was total nitrite plus nitrate nitrogen. Despite increases in fertilizer usage during 1982-91, most stream sites outside of the Twin Cities metropolitan area had no temporal trends in total nitrite plus nitrate nitrogen, total phosphorus, or dissolved orthophosphate concentrations for water years 1984-93. Most sites had a decrease in total ammonia nitrogen concentrations, possibly a result of improvements in wastewater treatment. In the Twin Cities metropolitan area, decreases in total ammonia concentrations in the Mississippi and Minnesota Rivers coincided with increases in total nitrite plus nitrate nitrogen concentrations, probably a result of wastewater treatment plants initiating nitrification processes. Nitrite plus nitrate nitrogen concentrations in ground water reflect land uses and hydrogeologic settings of major aquifers in the study area. Unconfined sand and gravel, buried sand and gravel, and the Prairie du Chien-Jordan were the aquifers most frequently sampled for nitrite plus nitrate nitrogen because they are the principal sources of ground water in the study area. The greatest nitrite plus nitrate nitrogen concentrations reported by Federal and state agencies, some exceeding the U.S. Environmental Protection Agency's Maximum Contaminant level of 10 mg/L by a factor of four, were in water from shallow wells in agricultural and mixed forested and agricultural areas. Water sampled from buried sand and gravel aquifers, which are more shielded from substances leaching from the land surface by layers of clay or till, generally had lower nitrite plus nitrate nitrogen concentrations than water from unconfined sand and gravel aquifers. Nitrite plus nitrate nitrogen concentrations in water samples from the Prairie du Chien-Jordan aquifer were greatest in the Wisconsin part of the study area and in the vicinity of the Cannon River, where the aquifer is commonly unconfined, exposed at land surface, and overlain by agricultural or by mixed forested and agricultural land covers. Dissolved phosphorus concentrations in ground water in the study area generally were near detection limits of 0.01 mg/L or lower, indicating that surface-water eutrophication from phosphorus may be more likely to occur from overland runoff of phosphorus compounds and from direct discharges of treated wastewater than from ground-water base flow. The greatest concentrations of dissolved phosphorus in ground water generally were detected in water samples from wells in urban portions of the study area.

Minnesota, Wisconsin↗

Few volatile organic compounds detected in rivers and ground water in the Upper Mississippi River Basin, Minnesota and Wisconsin

VOC’s are carbon-containing chemicals that readily evaporate at normal air temperature and pressure. They are contained in many commercial products such as gasoline, paints, adhesives, solvents, wood preservatives, dry-cleaning agents, pesticides, cosmetics, correction fluid, and refrigerants. Approximately 15 million pounds of VOC’s were released to the atmosphere in the focused study area (fig. 1) in 1992 by facilities registered with the U.S. Environmental Protection Agency. Millions of additional pounds of VOC’s are emitted to the atmosphere and to land and water by smaller unregistered users of these compounds in the focused study area.

Minnesota, Wisconsin↗