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Jerry L. Hughes

Publications and source records attributed to Jerry L. Hughes.

6 recordsLinked to original sources
USGS2006

Dissolved organic carbon (DOC), an index of organic contamination in ground water near Barstow, California

The alluvial aquifer underlying and adjacent to the Mojave River near Barstow, California, has been subjected to degradation from percolation of industrial and municipal wastes for more than 60 years. Effluents discharged to the aquifer have contained high concentrations of both organic (detergents, oil and grease, phenols, humic compounds, and others) and inorganic (chromium, chloride, phosphates, and others) substances. The concentration of dissolved organic carbon (DOC), as determined by a wet combustion technique, has been shown to be a definitive parameter in identifying ground water affected by waste disposal. DOC concentrations ranged from 0.1 to 0.8 milligram per liter in the nondegraded ground water and exceeded 6 milligrams per liter in the ground water affected by the waste discharge. The general distribution of DOC in the degraded ground water has been defined both areally and vertically. The vertical distribution of DOC and other constituents indicates that two plumes of degraded water occur at different depths. A comparison of the areal distribution of DOC and detergents (as MBAS) suggests that some organic compounds may have been adsorbed by the aquifer sediments.

California↗
USGS1979

Saltwater-barrier line in Florida: Concepts, considerations, and site examples

Construction of canals and enlargement of streams in Florida has been mostly to alleviate impact of floods and to drain wetlands for development. Land drainage and heavy pumpage from coastal water-table aquifers has degraded potable ground and surface water with saltwater. Control of saltwater intrusion is possible through implementation of certain hydrologic principles. State of Florida statute 373.033 provides for a saltwater-barrier line in areas of saltwater intrusion along canals. A saltwater-barrier line is defined as the allowable landward limit that a canal shall be constructed or enlarged or a stream deepened or enlarged without a salinity-control structure seaward of the saltwater-barrier line. The salinity control structure controls saltwater intrusion along a surface-water channel and assists in controlling saltwater intrusion into shallow aquifers. This report briefly reviews the fundamentals of saltwater intrusion in surface-water channels and associated coastal aquifers, describes the effects of established saltwater-barrier lines in Florida, and gives a history of the use and benefits of salinity-control structures. (Woodard-USGS).

Florida↗
USGS1977

Evaluation of ground-water quality in the Santa Maria Valley, California

The quality and quantity of recharge to the Santa Maria Valley groundwater basin from natural sources, point sources, and agriculture were evaluated. The results are expressed in terms of a hydrologic budget, a solute balance, and maps showing the distribution of selected chemical constituents in ground water. Point sources of waste discharge that could cause ground-water degradation were investigated including a sugar-beet refinery, oil refineries and oil-field wastewater, stockyards, golf courses, poultry farms, solid-waste landfills, and municipal and industrial wastewater-treatment facilities. Measurements of specific conductance of ground water and water levels in nearly 400 wells and the analyses of about 100 water samples for most major anions and cations plus detergents, dissolved organic carbon, and trace metals permitted preparation of maps showing the potentiometric surface and the distribution of dissolved solids, chloride, sulfate, calcium plus magnesium, and nitrogen in ground water. Pumpage of ground water for agricultural, municipal, and industrial uses has exceeded recharge by about 10,000 acre-feet per year (12.3 cubic hectometers per year). Most of the ground water pumped in the Santa Maria Valley is for agriculture. The result of pumping in excess of recharge is a declining potentiometric surface, an accumulation of solutes, and an increase in nitrogen in ground water. At present (1976), the area of confined water is most severely affected by this degradation. Nitrogen concentrations in ground water have reached as much as 50 milligrams per liter in isolated areas, with concentrations in excess of 10 milligrams per liter occurring through most of the area of confined water. Continued pumping in excess of recharge may also lower the potentiometric surface sufficiently to permit intrusion of seawater into the fresh-water zones. Discharge of wastewater from municipal and industrial wastewater-treatment facilities is also contributing solutes to the ground-water system. In comparison to the influences of irrigation return water on ground-water quality, the contribution from point sources is less than 10 percent of the total solutes. In some areas of the valley, the concentration of dissolved solids and some chemical constituents in water discharging from municipal and industrial wastewater-treatment facilities is lower than in the receiving ground water.

California↗
USGS1975

Hydrologic evaluation of the Haystack Butte area : with emphasis on possible discharge of class-I wastes, Edwards Air Force Base, California

The discharge of 3 acre-feet (4 x 10 -3 cubic hectometres) per year of Class-I wastes in the Haystack Butte area of Edwards Air Force Base, Calif., has been proposed by the Air Force. Evaporation in this arid basin exceeds the 4 inches (100 millimetres) of annual precipitation. Fifteen test holes, ranging in depth from 40 to 240 feet (12 to 73 metres) below land surface, indicate that ground water occurs mostly in Tertiary volcanic and sedimentary rocks overlying pre-Tertiary quartz monzonite. Depth to water averages about 100 feet (30 metres) below land surface. Hydraulic conductivity of cores of Tertiary rock taken from a test hole at depths of 9 to 88 feet (2.7 to 27 metres) below land surface suggests values of 6.9 x 10-5 to 4.9 x 10 -3 feet per day (2.1 x 10 -5 to 1.5 x 10 -3 metres per day). Petrographic analyses of these cores indicate a material consisting mostly of weathered volcanic rocks with a moderate concentration of montmorillonite clay. The water-level gradient averages about 4 feet per mile (0.76 metre per kilometre). Ground-water discharge through a narrow gap in the southeastern part of the basin is calculated to be 3.8 x 10 -4 acre-feet (4.7 x 10 -7 cubic hectometres) per year. After leaving the basin, the underflow becomes part of a regional flow system discharging into Harper Lake playa. An increase in the underflow from 3.8 x 10 -4 acre-feet (4.7 x 10 -7 cubic hectometres) per year to 3 acre-feet (4 x 10 -3 cubic hectometres) per year may result in an undesirable surface-water flow by increasing the saturated thickness of the aquifer near the narrow gap in the southeastern part of the basin. Also, the very low hydraulic-conductivity values suggest that some difficulties may exist in percolating 3 acre-feet (4 x 10 -3 cubic hectometres) per year of wastes resulting in possible saturation of the ground surface outside the boundaries of the potential Class-I site. Because the rate of evaporation is very high (116 inches or 294.6 millimetres per year) in the study area, many of the problems associated with the percolation of the waste water and the subsequent changes in ground-water movement could be minimized by evaporating the wastes to complete dryness. The quality of the ground water in the basin is generally unsuitable for domestic, industrial, and irrigation purposes. The concentration and type of chemical constituents in the ground water suggest slow circulation in a geologic environment with soluble minerals.

California↗