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B.G. Waller

Publications and source records attributed to B.G. Waller.

6 recordsLinked to original sources
USGS1987

Effluent migration from septic tank systems in two different lithologies, Broward County, Florida

Two septic tank test sites, one in sand and one in limestone, in Broward County, Florida, were analyzed for effluent migration. Groundwater from shallow wells, both in background areas and hydraulically down-gradient of the septic tank system, was sampled during a 16-month period from April 1983 through August 1984. Water quality indicators were used to determine the effluent affected zone near the septic tank systems. Specific conductance levels and concentrations of chloride, sulfate, ammonium, and nitrate indicated effluent movement primarily in a vertical direction with abrupt dilution as it moved down-gradient. Effluent was detected in the sand to a depth more than 20 ft below the septic tank outlet, but was diluted to near background conditions 50 ft down-gradient from the tank. Effluent in the limestone was detected in all three observation wells to depths exceeding 25 ft below the septic tank outlet and was diluted, but still detectable, 40 ft down-gradient. The primary controls on effluent movement from septic tank systems in Broward County are the lithology and layering of the geologic materials, hydraulic gradients, and the volume and type of use the system receives. (Author 's abstract)

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USGS1986

Chemical effects of highway runoff on the surficial aquifer, Broward County, Florida

In many areas of Broward County, swales are commonly designed to accept stormwater runoff from highways. Two sites adjacent to heavily traveled highways were studied to determine if stormwater percolating through unsaturated sand underlying the swales may affect the quality of water in the Biscayne aquifer. Concentrations of selected chemicals common in highway runoff were measured in swale stormwater, in the unsaturated-zone percolate, and in the surficial aquifer during 12 storms, May through November 1983. Analyses of the unsaturated lithologic material at the two sites and one control site were also made to indicate the extent of vertical attenuation of selected chemical constituents. Results of trace metal nutrient analyses indicated that there is no obvious water-quality effect on the surficial aquifer caused by highway runoff. In general, the data collected for dissolved trace metals indicated slight concentrations in stormwater samples with subsurface water samples usually indicating decreases in concentration below about 0.5 to 1 ft of unsaturated material. For most trace metals, the apparent decreases with depth were statistically significant based on nonparametric analysis of variance. Concentrations of dissolved nitrogen and phosphorus, however, were somewhat homogeneous and were not inferred to be significantly different with depth. Water hardness as calcium carbonate at both sites indicated a significant difference with depth because of calcium carbonate solution, but the effect of percolate hardness on the shallow groundwater was negligible because of regional mixing. The analyses of lithologic material at the two test sites indicated significant near-surface accumulation of some trace elements. For example, in the first foot below land surface, concentrations of iron, lead, and zinc were detected in the 1 to 7 mg/kg range, with concentrations decreasing sharply at lower depths. This near-surface accumulation was not indicated in the lithologic material at the control site. (Author 's abstract)

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USGS1985

Drought of 1980-82 in southeast Florida with comparison to the 1961-62 and 1970-71 droughts

South-central Florida (the Kissimmee Basin) experienced a severe drought during 1980-82, causing Lake Okeechobee--the largest surface-water storage area in south Florida--to reach the lowest stage ever recorded, 9.75 feet above sea level, on July 29, 1981. A prolonged period of deficient rainfall extended from June 1980 to March 1982. On the southeast coast, drought conditions were mitigated on August 16, 1981, when rainfall from Tropical Storm Dennis replenished the coastal aquifers and filled the water conservation areas to near scheduled levels. South Dade County was the only area in south Florida not affected by the drought. Rainfall in the southeast coastal areas had a statistical recurrence ranging from 5 to 20 years whereas the recurrence intervals from some stations in south-central Florida were in excess of 100 years. The 1980-81 drought in southeast Flrodia was not as severe as the 1961-62 or the 1970-71 droughts in terms of rainfall conditions or the effect on water levels. The effects of the drought were less severe because of a combination of water-management practices and periodic rainfall during the otherwise rain-deficient period. (USGS)

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USGS1982

Effects of land use on ground-water quality in the East Everglades, Dade County, Florida

Groundwater quality characteristics of the Biscayne aquifer from September 1978 through June 1979 were determined for seven land use areas within the East Everglades in Dade County, Florida. Four agricultural areas, two low-density residential areas, and Chekika Hammock State Park were investigated. The effects of land use on the groundwater were minimal in all areas; only iron , which occurs naturally in high concentrations in the Everglades, exceeded potable groundwater standards. Potassium and nitrate concentrations in certain samples increased over background concentrations in the agricultural areas. Groundwater at Chekika Hammock State Park and at a citrus grove is contaminated by brackish water flowing from an artesian well. The soil at the agricultural areas had higher concentrations of chromium, copper, and manganese than at the two residential areas or at Chekika Hammock State Park. One residential area (Coopertown) had the highest concentrations of lead and zinc and detectable polychlorinated biphenyls. Chlorinated-hydrocarbon insecticide residues in soil at three agricultural areas were higher than background concentrations. (Author 's abstract)

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USGS1978

Effects of land use and water management on water quality in the western South New River Canal basin: southeast Florida, 1974-75

The South New River Canal (C-11) basin between water-control structures S-9 and S-13 is an area that is primarily undeveloped and the system of waterways within the basin is highly controlled for water-management purposes. Most of the recharge to the canals is by induced ground-water inflow and seepage. The chemical character of the surface and ground waters in inundated areas is mixed calcium-bicarbonate and sodium-chloride type. Inorganic nitrogen concentrations in surface waters are slightly higher in developed areas than in undeveloped areas. Concentrations of inorganic nitrogen in ground water in drained areas are 2-4 times greater than in undeveloped inundated areas. Average orthophosphate concentrations are uniformly low (0.01 to 0.03 milligrams per liter) throughout the basin. Total residue concentrations are fairly uniform throughout the basin and fluctuate primarily in response to hydrologic conditions. Runoff and load-discharge indices indicated that the loads of inorganic nitrogen, total residue, and phosphorus, and the discharge per unit of land drained were uniform throughout most of the basin. (Woodard-USGS)

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