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M. J. Ellis

Publications and source records attributed to M. J. Ellis.

12 recordsLinked to original sources
USGS1995

Reconnaissance of ground-water quality in the Papio-Missouri River Natural Resources District, eastern Nebraska, July through September 1992

A reconnaissance of ground-water quality was conducted in the Papio-Missouri River Natural Resources District of eastern Nebraska. Sixty-one irrigation, municipal, domestic, and industrial wells completed in the principal aquifers--the unconfined Elkhorn, Missouri, and Platte River Valley alluvial aquifers, the upland area alluvial aquifers, and the Dakota aquifer--were selected for water-quality sampling during July, August, and September 1992. Analyses of water samples from the wells included determination of dissolved nitrate as nitrogen and triazine and acetanilide herbicides. Waterquality analyses of a subset of 42 water samples included dissolved solids, major ions, metals, trace elements, and radionuclides. Concentrations of dissolved nitrate as nitrogen in water samples from 2 of 13 wells completed in the upland area alluvial aquifers exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level for drinking water of 10 milligrams per liter. Thirty-nine percent of the dissolved nitrate-as-nitrogen concentrations were less than the detection level of 0.05 milligram per liter. The largest median dissolved nitrate-as-nitrogen concentrations were in water from the upland area alluvial aquifers and the Dakota aquifer. Water from all principal aquifers, except the Dakota aquifer, had detectable concentrations of herbicides. Herbicides detected included alachlor (1 detection), atrazine (13 detections), cyanazine (5 detections), deisopropylatrazine (6 detections), deethylatrazine (9 detections), metolachlor (6 detections), metribuzin (1 detection), prometon (6 detections), and simazine (2 detections). Herbicide concentrations did not exceed U.S. Environmental Protection Agency Maximum Contaminant Levels for drinking water. In areas where the hydraulic gradient favors loss of surface water to ground water, the detection of herbicides in water from wells along the banks of the Platte River indicates that the river could act as a line source of herbicides. Water from the alluvial and bedrock aquifers generally was a calcium bicarbonate type and was hard. Two of nine water samples collected from the Dakota aquifer contained calcium sulfate type water. Results of analyses of 42 groundwater samples for major ions, metals, trace elements, and radionuclide constituents indicated that statistically at least one principal aquifer had significant differences in its water chemistry. In general, the water chemistry of the Dakota aquifer was similar to the water chemistry of the upland area alluvial aquifers in areas where there was a hydraulic connection. The water from the Dakota aquifer had large dissolved-solids, calcium, sulfate, chloride, iron, lithium, manganese, and strontium concentrations in areas where the aquifer is thought not to be in hydraulic connection with the Missouri River Valley and upland area alluvial aquifers. Ground-water quality in the Papio-MissouriRiver Natural Resources District is generally suitable for most uses. However, the numerous occurrences of herbicides in water of the Elkhorn and Platte River Valley alluvial aquifers, especially near the Platte River, are of concern because U.S. Environmental Protection Agency Maximum Contaminant Levels could be exceeded. Concentrations in three of nine water samples collected from wells completed in the Dakota aquifer exceeded the U.S. Environmental Protection Agency Maximum Contaminant Levels or Secondary Maximum Contaminant Levels for gross alpha activity, radon-222 activity, dissolved solids, sulfate, or iron. Also of concern are the exceedances of the U.S Environmental Protection Agency proposed Maximum Contaminant Level for radon-222 activity.

Water-Resources Investigations Report↗
USGS1985

Evaluation of surface geophysical methods for collection of hydrogeologic data in the Nebraska Sand Hills region

The practicality of using surface geophysical methods for obtaining geohydrologic data in the Nebraska Sand Hills region was studied during the summer of 1984. Seismic refraction and electrical-resistivity equipment were used, because an evaluation of geohydrologic data indicated that results of surveys made with this equipment probably would yield the most useful data. The study area, which included parts of Garfield, Holt, and Wheeler Counties, was selected because it is geohydrologically representative of the eastern part of the Sand Hills region, and because sufficient geohydrologic data were available for use in evaluating the results of geophysical surveys. Geophysical methods were evaluated for their ability to consistently detect selected geohydrologic horizons. These horizons in descending order, are: the water table, the top of Quaternary silt beds, the top of Quaternary sand and gravel beds , the top of the Tertiary Ogallala Formation, and the top of the Cretaceous Pierre Shale. The top of the Pierre Shale generally is the base of the aquifer, which consists of all of the 500 to 700 ft of overlying deposits. Evaluations of the geophysical data indicate that seismic refraction surveys are best suited for determining the depth to the water table, but are not effective in studying beds below the water table. Vertical electrical soundings provided data on the depth to water table and the top of the silt beds. Available geohydrologic data, however, indicate that with some changes in data collection or interpretation techniques, it may be possible to obtain information on the top of the sand and gravel deposits, the top of the Ogallala Formation, and the top of the Pierre Shale with vertical electrical soundings. Use of either geophysical method could enhance the results of geohydrologic investigations in the Nebraska Sand Hills region. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1981

Geohydrologic reconnaissance of the Crofton Unit, northeastern Nebraska

This report describes the results of a reconnaissance of the sources, location, quantity, and quality of ground water in the proposed irrigation project area called the "Crofton Unit," an area of approximately 350 square miles in northeastern Nebraska. Precambrian Sioux Quartzite underlies the entire study area. Throughout most of the area, the Sioux is overlain by undifferentiated Paleozoic rocks. The Sioux and, where present, the Paleozoic rocks are overlain unconformably by Cretaceous formations, including both the Dakota and Niobrara Formations. Surface strata are Pleistocene and Holocene deposits of sand and gravel and Pleistocene deposits of glacial till. The Dakota and Niobrara Formations are each capable of yielding sufficient water for irrigation in parts of the area. Pleistocene and Holocene deposits yield adequate water for irrigation in the southern part of the area where saturated thicknesses range from 25 to 176 feet and along the flood plain of the Missouri River where saturated thicknesses range from 40 to 101 feet. Reported yields of 13 Pleistocene irrigation wells sampled for water-quality analyses averaged 857 gallons per minute. Water from wells developed in the Dakota Formation is a calcium sulfate type. Use of this water for successful long-term irrigation would necessitate burdensome salinity-control measures because of the salinity of the water. Water from wells developed in the Niobrara Formation is a calcium bicarbonate type and is suitable for irrigation of most crops. Water from wells developed in both Niobrara and Pleistocene deposits generally is a calcium sulfate type and may be used for irrigation of salt-tolerant crops with special measures for salinity control. The quality of water from Pleistocene and Holocene deposits is highly variable. In both the southern part of the area and along the Missouri River, water from these deposits is a calcium bicarbonate type and generally suitable for irrigation.

Nebraska↗
USGS1971

Hydrology of the Rosebud Indian Reservation, South Dakota

An investigation of the geology and ground-water resources of the Rosebud Indian Reservation, South Dakota, was made at the request of the Bureau of Indian Affairs as part of the U.S. Department of Interior's program for the development of the Missouri River basin. Originally, the Reservation included all of Mellette, Todd, and Tripp Counties; most of Gregory County, and a small part of Lyman County. (See index map.) However, of the 1,500 square miles of land now owned by individual Indians or by the Rosebud Sioux Tribe, nearly 95 percent is located in Mellette and Todd Counties. Accordingly, the area of this investigation (about 2,700 square miles) was restricted to these two counties.

South Dakota↗
USGS1971

Hydrogeology of the Pine Ridge Indian Reservation, South Dakota

An investigation of the geology and ground-water resources of the Pine Ridge Indian Reservation, South Dakota, was made at the request of the Bureau of Indian Affairs as part of the U.S. Department of the Interior's program for the development of the Missouri River basin. The area of investigation (about 3,930 square miles) includes all the land within the original boundaries of the Reservation, except for that part of Bennett County south of the U.S. Highway 18, where there are only small tracts of Indian land. Emphasis in the study was placed on mapping major rock units and on determining their potential as sources of water for domestic and stock use. The geologic map on sheet 1 shows the areal extent of the major rock units, and a summary of the stratigraphy and physical characteristics of the exposed geologic formations is given in the table on this sheet. The writers appreciate the cooperation of the personnel of the South Dakota State Geological Survey, who provided most of the well data for Bennett County, information about the stratigraphy and geology of selected areas, and copies of published and unpublished geologic maps. (See map showing areas mapped prior to this investigation.) Also, they appreciate the cooperation of ranch owners and tenants, who permitted access to their lands, and the personnel of the Bureau of Indian affairs, who supplied soils mps and other data. Data on which this report is based, including logs of wells and test holes, chemical analyses of water and records of wells and springs, have been summarized by the authors in a basic-data report published jointly by the South Dakota Geological Survey and South Dakota Water Resources Commission (Water Resources Report 4, Basic hydrogeologic data - Pine Ridge Indian Reservation, South Dakota). A selected bibliography of reports pertaining to the geology of the area has been included in the basic-data report. This atlas will be more useful if studied in conjunction with a copy of the basic-data report.

South Dakota↗