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K.J. Lucey

Publications and source records attributed to K.J. Lucey.

10 recordsLinked to original sources

Evaluation of drawdown and sources of water in the Mississippi River alluvium caused by hypothetical pumping, Muscatine, Iowa

A study was conducted to evaluate drawdown and volumetric changes in sources of water in the Mississippi River alluvium caused by hypothetical pumping. A steady-state, ground-water flow model was constructed for a previous study to simulate February 1993 hydrologic conditions, which were assumed to be an acceptable estimate of the ground-water system at equilibrium. The flow model was modified for this study to simulate six hypothetical pumping scenarios: five pumping scenarios to simulate hypothetical pumping at five pumping scenario sites, and a total pumping scenario to simulate cumulative hypothetical pumping from the five pumping scenario sites. The evaluation of drawdown for the six hypothetical pumping scenarios indicates that hypothetical pumping causes simulated drawdown that varies from about 10 ft to greater than 50 ft relative to February 1993 conditions at the five hypothetical pumping scenario sites. The simulated drawdown is less than half of the estimated saturated thickness of the alluvium during February 1993 at these sites. The primary sources of water (inflows) to the alluvium needed to balance the increased ground-water withdrawals (outflows) caused by hypothetical pumping are a combination of increased river leakage and decreased leakage to Muscatine Slough. Compared to February 1993 conditions, larger inflow rates occur as river leakage from the Mississippi River for the six hypothetical pumping scenarios. However, smaller outflow rates to Muscatine Slough compared to February 1993 conditions indicate that an important source of water for hypothetical pumping is ground-water discharge that would have become streamflow in the slough. Increased pumping at the hypothetical pumping scenario sites could affect long-term water quality and hydrology in the study area. The greater amounts of river leakage might affect overall ground-water quality in the alluvium. The lesser amounts of ground water being discharged to streamflow could have a long-term impact on the hydrology of the slough and adjacent wetland areas. The simplified steady-state flow model does not account for dynamic (transient) conditions (natural or development-related). The steady-state model does not indicate time needed to reach new equilibrium conditions. Attaining equilibrium might take many years and is complicated by varying climatic and hydrologic conditions; noncontinuous pumping and pumping that is cycled among well fields; and changing and seasonally varying irrigation pumpage.

Illinois, Iowa↗

Hydrogeology and water quality of the Mississippi River alluvium near Muscatine, Iowa, June 1992 through June 1994

A study of the Mississippi River alluvium near Muscatine, Iowa, was conducted to evaluate ground-water flow and water quality using data collected from June 1992 through June 1994. The study area included approximately 80 square miles in parts of Muscatine and Louisa Counties in Iowa and Rock Island and Mercer Counties in Illinois. A steady-state, ground-water flow model was constructed using February 1993 hydrologic conditions. Model results indicate that drawdown in the lower alluvium caused by the pumping centers in Iowa extends beneath the Muscatine Slough in the northwest part of the study area and beneath the Mississippi River in the central and northern parts of the area. The primary sources of ground water in the alluvium are recharge from precipitation, leakage from the Mississippi River, and infiltration of upland runoff. The bedrock is not a major contributor of ground water to the alluvium. The areal distribution of selected water-quality properties and constituents in ground water results from several factors. Localized large chloride and nitrite-plus-nitrate nitrogen concentrations could be indicative of contamination from human activity. Specific conductance and calcium, magnesium, and sulfate concentrations are larger in ground water near the boundary between the river valley and upland area and could result from infiltration of upland runoff or lithologic differences in the alluvium. Large iron or manganese concentrations occur in the ground water near the Mississippi River and Muscatine Slough that result from microbial processes and the presence of dissolved organic carbon. Temporal variations of concentrations for selected water-quality constituents in groundwater samples attest to the dynamic nature of the ground-water system as it responds to natural and human-induced changes in water quality. Leakage from the Mississippi River affects ground-water quality in the alluvium adjacent to the river. Temporal variations in water quality of the Mississippi River can be caused by seasonally, amount of discharge, or upstream human activities. The quality of ground water induced from discrete zones of the alluvium by the pumping centers in Iowa has implications for the entire ground-water resource. The ground-water flow model calculated that 10 percent of the water that enters the zone of active pumping on the Iowa side of the Mississippi River originates from the zone west and north of Muscatine Slough, and that 5.2 percent originates from the zone on the Illinois side of the Mississippi River east of the center of the river channel.

Illinois, Iowa↗

Selected nutrients in stormwater runoff from Davenport, Iowa, 1992

Flow-weighted composite samples of stormwater runoff from areas of different land use in Davenport, Iowa, were collected in the summer and fall of 1992 and analyzed for selected nutrients. Annual constituent loads were estimated for the area drained by the Davenport storm-sewer network. In all cases, the regression-equation estimate of mean annual load is less than the estimate obtained by using the method of the U.S. Environmental Protection Agency. The largest mean annual loads for total nitrite nitrogen, total nitrate nitrogen, total nitrite and nitrate nitrogen, total organic nitrogen, total ammonia and organic nitrogen, total nitrogen, and total phosphorus are associated with residential land, which covers 67.2 percent of the area drained. Using concentration data from this study, it is estimated that an average storm-producing runoff during the 7-day, 10-year low-flow discharge of the Mississippi River would contribute about 4 percent of the total ammonia and organic nitrogen load in the river. Precipitation-chemistry data indicate that substantial parts of the nitrate nitrogen and ammonia nitrogen contained in the stormwater runoff could be from precipitation.

Iowa↗

Effects of climatic variations over 11 years on nitrate-nitrogen concentrations in the Raccoon River, Iowa

Nitrate-nitrogen (NO3-N) concentrations at public water supply intakes on the Des Moines and Raccoon Rivers in Iowa exceeded the maximum contaminant level (MCL) of 10 mg L-1 for public water supplies established by the USEPA for extended periods of time from March through early August 1990. The excessive NO3-N levels followed 2 yr of less-than normal precipitation in 1988 and 1989. The largest daily NO3-N load (771 t) transported during the last 17 yr in the Raccoon River occurred in June 1990. The streamflow hydrograph for the Raccoon River for March 1990 prior to seasonal fertilizer application indicates that high NO3-N concentrations characterize the recession side of the hydrograph. High NO3-N concentrations in streamflow persisted as streamflow decreased to baseflow conditions. This implies that substantial quantities of NO3-N were being leached from the soil and transported by subsurface flow during early 1990. A multiple linear-regression model was developed to predict NO3-N concentrations in the Raccoon River from readily-obtainable streamflow and climatic data. The four-variable model explained about 70% of the variability in the concentration of NO3-N. The mean streamflow for the previous 7-d period accounted for about 50% of the total variability.

Iowa↗

Analysis of the ground-water flow system, geochemistry, and underseepage in the vicinity of the Red Rock Dam near Pella, Iowa

The U.S. Army Corps of Engineers operates the Red Rock Dam on the Des Moines River in Marion County, Iowa. The dam consists of a gravity concrete control structure between two earthen embankments and has an impoundment storage capacity of 1,700,000 acre-feet. Since the impoundment of Lake Red Rock commenced during 1969, water seepage beneath the dam has been significant enough to cause continuing investigation by the Corps of Engineers of its source and implications. The St. Louis Limestone, which consists of interbedded sandstones and carbonates with solution collapse features resulting from partial removal of a basal evaporite zone, forms the bedrock foundation of the dam in the river valley. The soluble gypsum and anhydrite in the evaporite zone have the potential to be removed in greater quantity with increasing seepage velocities and volumes. Solution channels may develop as material is removed from the bedrock foundation, which could result in the collapse of overlying strata, thereby threatening the integrity of the earthen dam. The potentiometric surface in the overburden on the southwest side of the dam has an extremely steep hydraulic gradient from the reservoir through the dam to the downstream observation wells, which implies expected small permeability and minimal seepage through the dam and embankment materials. A lesser hydraulic gradient exists on the northeast side of the dam, which could indicate excessive seepage through embankment material from larger than expected hydraulic conductivity or underseepage through bedrock. Statistical analysis of water-level changes in the reservoir and in observation wells completed in the evaporite stratigraphic horizon on the northeast side of the dam indicates a hydraulic connection between the reservoir and the wells. Direct evidence of the existence of a connection between the reservoir and the ground-water system is provided by chloride concentration data. Maximum chloride concentrations occurred in the reservoir water in the early spring of 1989. Chloride concentrations reached a maximum in ground water from bedrock and overburden observation wells on the northeast side of the dam 1 to 4 months after their maximum in the reservoir. Underseepage of reservoir water occurs through the basal evaporite zone of the St. Louis Limestone and through the glacial sands in the northeast bluff between the bedrock surface and the base of the dam fill. The increased hydraulic head imposed on the system by the impounded waters of Lake Red Rock causes recharge and flow to the deeper bedrock aquifers in the immediate vicinity of the dam. This effect is manifested in the observation wells along and downstream from the dam axis, implying flow through the grout curtain in the bedrock foundation of the dam. There is potential for dissolution of the gypsum and anhydrite in the bedrock foundation, because reservoir water and shallow ground water in the vicinity of the dam are undersaturated with respect to these evaporite minerals.

Iowa↗

QADATA user's manual; an interactive computer program for the retrieval and analysis of the results from the external blind sample quality- assurance project of the U.S. Geological Survey

The U.S. Geological Survey conducts an external blind sample quality assurance project for its National Water Quality Laboratory in Denver, Colorado, based on the analysis of reference water samples. Reference samples containing selected inorganic and nutrient constituents are disguised as environmental samples at the Survey 's office in Ocala, Florida, and are sent periodically through other Survey offices to the laboratory. The results of this blind sample project indicate the quality of analytical data produced by the laboratory. This report provides instructions on the use of QADATA, an interactive, menu-driven program that allows users to retrieve the results of the blind sample quality- assurance project. The QADATA program, which is available on the U.S. Geological Survey 's national computer network, accesses a blind sample data base that contains more than 50,000 determinations from the last five water years for approximately 40 constituents at various concentrations. The data can be retrieved from the database for any user- defined time period and for any or all available constituents. After the user defines the retrieval, the program prepares statistical tables, control charts, and precision plots and generates a report which can be transferred to the user 's office through the computer network. A discussion of the interpretation of the program output is also included. This quality assurance information will permit users to document the quality of the analytical results received from the laboratory. The blind sample data is entered into the database within weeks after being produced by the laboratory and can be retrieved to meet the needs of specific projects or programs. (USGS)

Open-File Report↗

Quality-assurance data for routine water analysis in the National Water-Quality Laboratory of the US Geological Survey for water year 1988

The US Geological Survey maintains a quality assurance program based on the analysis of reference samples for its National Water Quality Laboratory located in Denver, Colorado. Reference samples containing selected inorganic, nutrient, and precipitation (low-level concentration) constituents are prepared at the Survey 's Water Quality Services Unit in Ocala, Florida, disguised as routine samples, and sent daily or weekly, as appropriate, to the laboratory through other Survey offices. The results are stored permanently in the National Water Data Storage and Retrieval System (WATSTORE), the Survey 's database for all water data. These data are analyzed statistically for precision and bias. An overall evaluation of the inorganic major ion and trace metal constituent data for water year 1988 indicated a lack of precision in the National Water Quality Laboratory for the determination of 8 out of 58 constituents: calcium (inductively coupled plasma emission spectrometry), fluoride, iron (atomic absorption spectrometry), iron (total recoverable), magnesium (atomic absorption spectrometry), manganese (total recoverable), potassium, and sodium (inductively coupled plasma emission spectrometry). The results for 31 constituents had positive or negative bias during water year 1988. A lack of precision was indicated in the determination of three of the six nutrient constituents: nitrate plus nitrite nitrogen as nitrogen, nitrite nitrogen as nitrogen, and orthophosphate as phosphorus. A biased condition was indicated in the determination of ammonia nitrogen as nitrogen, ammonia plus organic nitrogen as nitrogen, and nitrate plus nitrite nitrogen as nitrogen. There was acceptable precision in the determination of all 10 constituents contained in precipitation samples. Results for ammonia nitrogen as nitrogen, sodium, and fluoride indicated a biased condition. (Author 's abstract)

Water-Resources Investigations Report↗