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G. L. Barr

Publications and source records attributed to G. L. Barr.

26 records · Page 2Linked to original sources
USGS1982

Ground-water levels in selected well fields and in west-central Florida, September 1981

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well fields that supplied 140.3 million gallons to municipalities on September 21, 1981. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal on ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. In September 1981, ground-water levels were significantly higher than those of May 1981 and were unchanged or within a few feet of those in September 1980. Seasonal recharge from summer rains and reduced pumpage are factors in the water-level recovery from record and near record low levels of May 1981. (USGS)

Open-File Report↗
USGS1982

Potentiometric surface of the Floridan aquifer, Southwest Florida Water Management District, May 1982

A May 1982 potentiometric surface map of the Southwest Florida Water Management District depicts the annual low water-level period. Water levels in most wells measured in May 1982 were lower than in September 1981. Levels averaged about 9 feet lower in the southern part of the area and 1.5 feet lower in the north. In agricultural areas of southern Hillsborough, Manatee, southwestern Polk, southern Hardee, northwestern De Soto, and northern Sarasota Counties, water-level declines ranged from 5 feet to 29 feet. From May 1981 to May 1982, water-level increases ranged from about 3 feet in the northern counties to about 20 feet in the middle and southern counties. Water-level increases were about 4 feet in the extreme southern part of the study area.

Florida↗
USGS1982

Ground-water levels in selected well fields and in west-central Florida, May 1982

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,700-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with the seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well fields that supplied 181.1 million gallons to municipalities on May 10, 1982. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal on ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. In May 1982, ground-water levels were lower than those of September 1981. Seasonal recharge from above-average rainfall and reduced pumpage aided in the water-level recovery from record to near record levels of May 1981. (USGS)

Open-File Report↗
USGS1981

Water-quality data from a landfill-leachate treatment and disposal site, Pinellas County, Florida, January 1979-August 1980

Water-quality data collected between January 1979 and August 1980 at the landfill leachate treatment site in Pinellas County, Fla., are presented. Data include field and laboratory measurements of physical properties, major chemical constituents , nitrogen and phosphorus species, chemical oxygen demand, trace metals, coliform bacteria, taxonomy of macroinvertebrates and phytoplankton, and chlorophyll analyses. Data were collected as part of a study to determine water-quality changes resulting from aeration and ponding of leachate pumped from landfill burial trenches and for use in determining the rate of movement and quality changes as the leachate migrates through the surficial aquifer. Samples were collected from 81 surficial-aquifer water-quality monitoring wells constructed in January 1975, February 1979, and March 1979, and 8 surface-water quality monitoring sites established in January 1975, February 1978, and November 1978.

Florida↗
USGS1980

Configuration of the top of the highly permeable dolomite zone of the Floridan Aquifer, Southwest Florida Water Management District

This map report presents the configuration of the top of the highly permeable dolomite zone of the Floridan aquifer in the Southwest Florida Water Management District. The top of the highly permeable dolomite generally corresponds to the top of a thick bed of massive, hard, dark brown dolomite occurring in the Avon Park Limestone of Eocene age. The altitude of the top of the permeable dolomite varies from about 100 feet below the National Geodetic Vertical Datum of 1929 in the north to about 1 ,600 feet below the datum in the south. (Kosco-USGS)

Open-File Report↗
USGS1979

Generalized thickness of the confining bed overlying the Floridan Aquifer, Southwest Florida Water Management District

This map presents the thickness of the confining bed overlying the Floridan aquifer in the Southwest Florida Water Management District and adjacent areas. The bed separates the surficial aquifer from the underlying Floridan aquifer. Lithologic logs and information from quarries were used in conjunction with an unpublished map to compile this map at 1:250,000 scale. Units included in the confining bed are: clay, sandy clay and marl, undifferentiated with respect to age, the Hawthorn Formation, and the unconsolidated sections of the Tampa Limestone. (Kosco-USGS)

Open-File Report↗
USGS1979

Generalized configuration of the bottom of the Floridan aquifer, Southwest Florida Water Management District

This map presents the configuration of the bottom of the Floridan aquifer in the Southwest Florida Water Management District. The bottom of the aquifer generally corresponds to the beginning of consistent intergranular evaporites occurring in either the Avon Park, Lake City, or Oldsmar Limestones of Eocene age. The altitude of the bottom of the aquifer varies from about 600 feet below the National Geodetic Vertical Datum of 1929 in the north to about 3,000 feet below the datum in the South. (Kosco-USGS)

Florida↗