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J. L. Imes

Publications and source records attributed to J. L. Imes.

10 recordsLinked to original sources
USGS2009

Eolian transport of geogenic hexavalent chromium to ground water

A conceptual model of eolian transport is proposed to address the widely distributed, high concentrations of hexavalent chromium (Cr +6 ) observed in ground water in the Emirate of Abu Dhabi, United Arab Emirates. Concentrations (30 to more than 1000 μg/L Cr +6 ) extend over thousands of square kilometers of ground water systems. It is hypothesized that the Cr is derived from weathering of chromium-rich pyroxenes and olivines present in ophiolite sequence of the adjacent Oman (Hajar) Mountains. Cr +3 in the minerals is oxidized to Cr +6 by reduction of manganese and is subsequently sorbed on iron and manganese oxide coatings of particles. When the surfaces of these particles are abraded in this arid environment, they release fine, micrometer-sized, coated particles that are easily transported over large distances by wind and subsequently deposited on the surface. During ground water recharge events, the readily soluble Cr +6 is mobilized by rain water and transported by advective flow into the underlying aquifer. Chromium analyses of ground water, rain, dust, and surface (soil) deposits are consistent with this model, as are electron probe analyses of clasts derived from the eroding Oman ophiolite sequence. Ground water recharge flux is proposed to exercise some control over Cr +6 concentration in the aquifer.

Ground Water↗
USGS1996

Analysis of regional aquifers in the central Midwest of the United States in Kansas, Nebraska, and parts of Arkansas, Colorado, Missouri, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming: Summary

Large quantities of ground water are available for use from three regional aquifer systems in the central Midwest of the United States. Parts of the lowermost aquifer contain nearly immobile brine and may be hydrologically suitable for material storage or waste disposal. Results of numerical modeling and geochemical analyses confirm general concepts of ground-water flow in the regional aquifer systems.

Arkansas, Colorado, Kansas, Missouri, Nebraska, Ne↗
USGS1989

Compilation of geohydrologic data collected as part of the areal appraisal of ground-water resources near Branson, Missouri

A rapidly developing retirement community and tourist industry in the Branson, Missouri area has created an increased demand for potable water, especially in the summer months. The rapid pace of residential and business expansion has created concerns regarding the future groundwater availability and quality. Water levels measured in the Ozark aquifer during the summer of 1988 and March 1989 show water levels increasing in 22 wells, decreasing in 2 wells, and remaining the same in 1 well. The water level increases ranged from 1 to 111 ft. These measurements and similar measurements during the summer of 1989 will be used to calibrate a three-dimensional model of groundwater flow in the Branson area and estimate the long-term effect of large groundwater withdrawals during the summer tourist season. A reconnaissance of water quality in 34 wells that are open to the Ozark aquifer shows specific conductance ranging from 347 to 841 microsiemens/cm at 25 C and no fecal coliform bacteria present in any well. Chloride and nitrate concentrations in all wells were well below the Missouri Department of Natural Resources recommended maximum concentrations of 250 mg/L and 10 mg/L, respectively. Analysis of 5 water samples for 33 volatile organic compounds failed to detect any concentrations in excess of the detection limits. (USGS)

Open-File Report↗
USGS1989

Analysis of the effect of pumping on ground-water flow in the Springfield Plateau and Ozark aquifers near Springfield, Missouri

Pumpage of water from the Ozark aquifer for public supply and industry use by the city of Springfield and surrounding communities in southwestern Missouri has significantly altered the potentiometric surface of the aquifer. Springfield is located on a regional groundwater divide that trends east and west across southern Missouri. Groundwater that once flowed north and south from the divide now moves toward Springfield. Drawdown in the Ozark aquifer beneath Springfield has increased about 50 ft near the center of the city since 1974. The area of well influence also has increased, most notably to the south and southwest, because of increased pumpage by Springfield and new groundwater withdrawals in rapidly increasing communities, such as Republic and Nixa. Changes in the potentiometric surface of the Ozark aquifer, and to a lesser extent the Springfield Plateau aquifer, resulting from stresses applied by pumpage of water supply wells has altered the hydrologic budget of the Springfield area. Downward leakage of groundwater through the Ozark confining unit has increased from about 10 cu ft/sec to about 18 cu ft/sec because drawdown in the Ozark aquifer has resulted in an increased vertical hydraulic gradient across the confining unit. Minimal quantities of water are supplied by increased upward leakage through the St. Francois confining unit. Model simulations indicate substantial quantities of water are still (1987) being removed from storage within the Ozark and Springfield Plateau aquifers and the hydrologic system is not in equilibrium at this time. (USGS)

Water-Resources Investigations Report↗
USGS1984

Ground-water resources of Audrain County, Missouri

The deep (principal) aquifer in Audrain County has an average thickness of about 1,300 feet and is composed of dolomite and minor quantities of sandstone of Cambrian and Ordovician age. The deep aquifer is the source of water for all public-supply and irrigation wells in Audrain County. Pumpage from the deep aquifer has caused a decrease in hydraulic head of more than 200 feet since 1900 in the vicinity of the city of Mexico. Calculations from a two-dimensional digital model of the deep aquifer indicate that the drawdown would increase 10 to 25 feet from May 1979 levels in Audrain County by May 2000 in the absence of irrigation pumpage and if public-supply wells continue to pump at the 1980 rate. If the additional stress due to seasonal irrigation is continued at 1980 pumping rates, 60 +/- 20 feet of drawdown is predicted by May 2000. Audrain County is the northernmost extent of freshwater in this aquifer in Missouri. In Audrain County the dissolved-solids concentration of water from this aquifer varies from 1,200 milligrams per liter in the north to less than 400 milligrams per liter in the south. Lowered water levels in the aquifer may allow water with a larger dissolved-solids concentration to move into the area. (USGS)

Open-File Report↗