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W. R. Aucott

Publications and source records attributed to W. R. Aucott.

10 recordsLinked to original sources
USGS2006

Ground-water flow in the Coastal Plain aquifers of South Carolina

The characteristics of the Coastal Plain aquifers of South Carolina are being studied as a part of the Regional Aquifer System Analysis program of the United States Geological Survey. Potentiometric maps were constructed for the Middendorf aquifer of Cretaceous age and for the Floridan aquifer system and its sand facies equivalent, Tertiary sand aquifer, prior to development. Also constructed was a potentiometric decline map for the period prior to development to November 1982 for the Middendorf aquifer. These maps are used to describe the ground-water flow system. The Coastal Plain aquifers are recharged primarily by precipitation in their outcrop areas. Ground water flows from these areas of recharge, through the aquifers, and discharges to upper Coastal Plain rivers, overlying aquifers as upward leakage, and wells. Ground-water flow in the Floridan aquifer system and the Tertiary sand aquifer prior to development is generally perpendicular to the coast. Predevelopment flow in the Cretaceous aquifers, however, turns northeastward as it approaches the coast, almost paralleling the coast. The change in flow direction is caused by less effective intervening confining units, the aquifers being closer to the land surface, and the rivers at lower altitudes farther upstream in the vicinity of the North Carolina/South Carolina State line. Water-level declines in the Cretaceous aquifers have occurred throughout much of the eastern part of the Coastal Plain of South Carolina due to pumpage in the Myrtle Beach and Florence areas. Large areally extensive water-level declines have also occurred in the Floridan aquifer system in South Carolina due to pumpage in the Savannah, Georgia area.

South Carolina↗
USGS1989

Evaluation of methodology for delineation of protection zones around public-supply wells in west-central Florida

Public-supply wells in the west-central Florida area of Citrus, Hernando, Pasco, Hillsborough, and Pinellas Counties derive their supply solely from the Floridan aquifer system. In much of this area, the Floridan is at or near land surface and vulnerable to contamination. Recognizing this potential threat to the aquifer, the Florida Department of Environmental Regulation (FDER) recently promulgated regulations providing for the delineation of protection zones around public-supply wells that tap vulnerable aquifers, such as the Floridan in west-central Florida. This report evaluates the methodology for delineation of protection zones for public supply wells in west-central Florida in accordance with the methods detailed in the FDER regulations. Protection zones were delineated for public supply wells or well fields that are permitted an average daily withdrawal of 100,000 gal or more from the Floridan aquifer system where it is unconfined or leaky confined. Leaky confined, as used in FDER regulations describe conditions such that the time for a particle of water to travel vertically from the water table to the top of the Floridan is 5 years or less. Protection zones were delineated by using a radial volumetric-displacement model that simulated 5 years of permitted-rate withdrawal. Where zones overlapped, such as for well fields, composite protection zones in shapes that varied according to the configuration of well arrays were delineated on maps.

Florida↗
USGS1987

Regional ground-water discharge to large streams in the upper coastal plain of South Carolina and parts of North Carolina and Georgia

Base flow was computed to estimate discharge from regional aquifers for six large streams in the upper Coastal Plain of South Carolina and parts of North Carolina and Georgia. Aquifers that sustain the base flow of both large and small streams are stratified into shallow and deep flow systems. Base-flow during dry conditions on main stems of large streams was assumed to be the discharge from the deep groundwater flow system. Six streams were analyzed: the Savannah, South and North Fork Edisto, Lynches, Pee Dee, and the Luber Rivers. Stream reaches in the Upper Coastal Plain were studied because of the relatively large aquifer discharge in these areas in comparison to the lower Coastal Plain. Estimates of discharge from the deep groundwater flow system to the six large streams averaged 1.8 cu ft/sec/mi of stream and 0.11 cu ft/sec/sq mi of surface drainage area. The estimates were made by subtracting all tributary inflows from the discharge gain between two gaging stations on a large stream during an extreme low-flow period. These estimates pertain only to flow in the deep groundwater flow system. Shallow flow systems and total base flow are > flow in the deep system. (USGS)

Georgia, North Carolina, South Carolina↗
USGS1986

Hydrologic and geologic analysis of two wells in Marion County, South Carolina

Two test wells were drilled in Marion County, South Carolina in 1982. Well MRN 77 (Marion 77) was drilled to a depth of 365 ft and was used as an observation well in the Black Creek aquifer and to supply water during drilling of the deeper well. MRN 78 (Marion 78) was drilled and cored through the entire thickness of Coastal Plain sediments into the underlying basement rock to a depth of 1,225 ft. Data from the wells include description of the core samples from MRN 78, geophysical logs, zone water levels, chemical analysis of the water sampled and results of tests for mineral content. Head in MRN 78 increases with depth. The waters sampled were all sodium bicarbonate type except for the deepest zone (1,120-1,140 ft) sampled in MRN 78, which yielded a sodium chloride type water. (Lantz-PTT)

South Carolina↗
USGS1986

Selected aquifer-test information for the coastal plain aquifers of South Carolina

Aquifer and well hydraulic characteristics were determined from more than 100 multiple-well and single-well aquifer tests in the Coastal Plain of South Carolina and tabulated by county. Multiple-well aquifer tests were analyzed by the This method for nonleaky aquifers and the Hantush-Jacob method for leaky aquifers. Single-well tests were analyzed by straight line solution techniques for drawdown and recovery tests. Specific-capacity data are presented for many areas where aquifer-test information is sparse. The characteristics determined are based largely on well performance tests conducted by well drillers and consulting engineers. Although use of this information has many limitations, it has value in establishing transmissivity and storage coefficient values for the Coastal Plain aquifers. (Peters-PTT)

South Carolina↗
USGS1985

Water-supply potential of the Floridan aquifer in Osceola, eastern Orange, and southwestern Brevard counties, Florida

The city of Melbourne and adjacent areas in south Brevard County obtain their water supply from Lake Washington. As of 1982, the lake could provide a maximum of 15 million gallons per day but the projected need for the year 2000 is nearly three times that amount. As one alternative for a future water supply, this study investigated with a digital model, the potential yields of well fields completed in the Floridan aquifer. Seven pumping schemes were simulated with the digital model. Each simulation was made under steady-state conditions so that storage properties of the ground-water system were not included. The most advantageous area for ground-water development was in central Osceola County. Poor quality of water precluded locating a well field within Brevard County. If the ground-water alternative is chosen for the future supply, an observation well network is advisable to monitor head changes; chloride concentration trends east of the pumping centers; and chloride concentration trends in zones below the pumped zone.

Florida↗