Geology topics

Neville G. Gaggiani

Publications and source records attributed to Neville G. Gaggiani.

5 recordsLinked to original sources

USGS1994

Effects of land disposal of municipal sewage sludge on fate of nitrates in soil, streambed sediment, and water quality

This study was undertaken to determine the effects of sewage-sludge disposal at the Lowry sewage-sludge-disposal area, near Denver, Colorado, on ground- and surface-water quality, to determine the fate of nitrates from sludge leachate, and to determine the source areas of leachate and the potential for additional leaching from the disposal area. Sewage-sludge disposal began in 1969. Two methods were used to apply the sludge: burial and plowing. Also, the sludge was applied both in liquid and cake forms. Data in this report represent the chemical composition of soil and streambed sediment from seven soil- and four streambed-sampling sites in 1986, chemical and bacterial composition of ground water from 28 wells from 1981 to 1987, and surface-water runoff from seven water-sampling sites from 1984 to 1987. Ground water samples were obtained from alluvial and bedrock aquifers. Samples of soil, streambed sediment, ground water and surface water were obtained for onsite measurement and chemical analysis. Measurements included determination of nitrogen compounds and major cations and anions, fecal-coliform and -streptococcus bacteria, specific conductance, and pH. Thirteen wells in the alluvial aquifer in Region 3 of the study area contain water that was probably affected by sewage-sludge leachate. The plots of concentration of nitrate with time show seasonal trends and trends caused by precipitation. In addition to yearly fluctuation, there were noticeable increases in ground-water concentrations of nitrate that coincided with increased precipitation. After 3 years of annual ground-water-quality monitoring and 4 years of a quarterly sampling program, it has been determined that leachate from the sewage-sludge-disposal area caused increased nitrite plus nitrate (as nitrogen) concentration in the alluvial ground water at the site. Soil analyses from the disposal area indicate that organic nitrogen was the dominant form of nitrogen in the soil. As a result of investigations at the research site, it has been determined that a potentially large source of contamination exists in the soils of the study area owing to increased concentrations of nitrogen, sodium, calcium, magnesium, sulfate, bicarbonate, and chloride because of sewage disposal. Continued monitoring of surface and ground water for nitrogen and the other ions previously mentioned is required to assess long-term effects of municipal sludge disposal on water quality.

Journal of Hydrology↗

USGS1991

Selected hydrologic data for farmland treated with sewage sludge near Platteville, Colorado, 1985-91

The U.S. Geological Survey, in cooperation with the Metro Wastewater Reclamation District, studied the ground-water-quality effects of the application of anaerobic digested municipal sewage sludge at agronomic rates to farmland near Platteville. Beginning in the fall of 1985, the sludge was injected annually into the sandy farmland in a 1-square-mile area. Generally, water-quality samples were collected from observation wells two or three times during each irrigation season from 1985 through 1990 and once each winter or late spring from 1987 through early 1991. Water levels were measured, and water-quality, soil and soil-moisture samples, and precipitation data were collected at selected sites throughout the study area. This report presents the data collected during 1985-91 from observation wells, irrigation wells, domestic wells, and other selected sites in the study area.

Colorado↗

USGS1980

Calibration and testing of selected portable flowmeters for use on large irrigation systems

Existing methods for measuring discharge of irrigation systems in the High Plains region are not suitable to provide the pumpage data required by the High Plains Regional Aquifer System Analysis. Three portable flowmeters that might be suitable for obtaining fast and accurate discharge measure-ments on large irrigation systems were tested during 1979 under both laboratory and field conditions: propeller type gated-pipe meter, a Doppler meter, and a transient-time meter. The gated-pipe meter was found to be difficult to use and sensitive to particulate matter in the fluid. The Doppler meter, while easy to use, would not function suitably on steel pipe 6 inches or larger in diameter, or on aluminum pipe larger than 8 inches in diameter. The transient-time meter was more difficult to use than the other two meters; however, this instrument provided a high degree of accuracy and reliability under a variety of conditions. Of the three meters tested, only the transient-time meter was found to be suitable for providing reliable discharge measurements on the variety of irrigation systems used in the High Plains region.

High Plains Aquifer↗

USGS1978

Chemical and biological quality of Lakes Faith, Hope, and Charity at Maitland, Florida, with emphasis on the effects of storm runoff and bulk precipitation, 1971-1974

Located in a closed basin, near Orlands, Fla., Lake Faith, Hope, and Charity cover a combined area of 132 acres and are surrounded by residential, citrus grove and undeveloped areas. All of these areas affect the water quality of the lakes through storm runoff and transport of windborne material. During a study from April 1971 to June 1974, stages of Lakes Faith, Hope, and Charity declined 1.5, 1.4, and 3.0 ft, respectively, because the rainfall was 3.78 in. below average for the area. Inflow to the lakes during this 3-year period was approximately 1,966 acre-ft of which 84 percent was by rainfall and 16 percent was by storm runoff. Rainfall and runoff brought in 82 tons of dissolved solids of which storm runoff carried 51 tons and bulk precipitation carried 32 tons. Dissolved solids concentrations in the lakes were relatively low, averaging 91, 132, and 212 mg/liter for Lakes Faith, Hope, and Charity, respecetively. Major ions, trace elements and nutrients were present in the lakes in relatively low concentrations. Phytoplankton and coliform population showed sharp seasonal fluctuations with the maximum population generally occurring during the warmer months. Blue-green algae predominated in all three lakes. (Woodard-USGS)

Open-File Report↗

USGS1977

Limnological characteristics of Cypress Lake, Upper Kissimmee River Basin, Florida

Cypress Lake is in the upper Kissimmee River basin in Florida between Lake Tohopekaliga and Lake Hatchineha. It is remote from urban development and extensive agriculture. Nevertheless, most of the inflow to the lake, about 302,000 acre-ft per year, comes from 2 canals and a creek that drain the upper part of the basin which receives effluent from about 35 percent of the Orlando metropolitan area. With this inflow and a lake volume of 26,100 acre-ft, water in the lake is renewed about every 0.1 year. Cypress Lake has a surface area of 6.4 sq mi, a mean depth of 6.4 ft, an immediate overland drainage area of 29 sq mi and with Lake Hatchineha, receives drainage from 1,162 sq mi. From 1950 to 1964, before locks and dams at the outlets of Lakes Kissimmee and Tohopekaliga regulated water levels at Cypress Lake, water levels fluctuated from 57 ft msl to 48 ft msl, periodically flooding the surrounding area. After regulation from 1964 to 1975, the maximum water level at Cypress Lake was slightly more than 54 ft msl. Specific conductance of the water increased in Cypress Lake from an average of 76 micromho/cm in 1954-65 before regulations to 130 micromho/cm in 1964-75 after regulation. Cypress Lake is classified as a colored alkaline lake with an average color of 79 platinum cobalt units. Emergent marsh vegetation covers almost all the shoreline of the lake. (Woodard-USGS)

Florida↗