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H.E. Blanchard

Publications and source records attributed to H.E. Blanchard.

4 recordsLinked to original sources
USGS1986

Occurrence and availability of ground water in the Athens region, northeastern Georgia

A study was conducted to assess the occurrence and availability of groundwater in the crystalline rocks of the Piedmont area in northeastern Georgia and to determine whether groundwater is a viable alternative or supplemental source for industrial, public and private supplies. The area is underlain by a variety of metamorphic and igneous rocks. The quantity of water that a rock unit can supply to wells is determined by the number, capacity, and interconnection of the secondary openings. Of an estimated 10,000 successful wells drilled in the Athens Region, 972 wells are reported by drilling contractors to supply from 20 to 300 gal/min. Studies of well sites revealed that high yielding wells can be developed only where the water bearing units have undergone significant increases in secondary permeability. This occurs mainly in association with (1) contact zones between rock units of contrasting character, (2) contact zones within multilayered rock units, (3) fault zones, (4) stress-relief fractures, and (5) shear zones. Groundwater may be a viable alternative or supplemental source for industrial, public, and private supplies in much of the Athens Region. In 1980, groundwater made up 38% (18 million gal/day) of the total water used in the area. Yields of 20 to more than 200 gal/min are obtained from wells throughout most of the region, and the water is generally of good chemical quality and is suitable for drinking and many other uses. Concentrations of dissolved constituents are fairly consistent throughout the area. Except for iron, manganese, and fluoride, dissolved constituents rarely exceed drinking water standards. (Lantz-PTT)

Georgia↗
USGS1978

A preliminary appraisal of the impact of agriculture on ground-water availability in southwest Georgia

Irrigated acreage in the study area in southwest Georgia increased from 130,000 acres in 1976 to 261,000 in 1977. Acreage irrigated entirely by ground water increased 85 percent for the same period. The largest quantity of ground water used for irrigation was in the Dougherty Plain district, where 92 percent of supplemental irrigation water comes from wells. In the Tifton Upland district, ground water is the source for only 16 percent of the irrigation water used. The major ground-water reservoir supplying the irrigation water is the principal artesian aquifer. The Dougherty Plain, because of the gently rolling land surface and large fields, is suitable for the use of large self-propelled center-pivot irrigation systems requiring 1,200 to 1,500 gallons per minute. The installed pump capacity of the irrigation systems in the Dougherty Plain using ground water was 1.8 billion gallons per day in 1977. The total amount of water pumped for irrigation in the Dougherty Plain in 1977 was more than 42 billion gallons, 30 billion gallons more than in 1976. This quantity could be considerably higher in 1978 as preparations were being made to irrigate more than 214,000 acres during the 1978 growing season. There were no concentrations of selected organic compounds or trace metals used in agricultural chemicals above the recommended limits for public consumption in water analyzed from 19 wells. However, concentrations of total nitrite plus nitrate ranged from 0.3 to 7.8 milligrams per liter in wells in the Dougherty Plain, and this could indicate that the downward percolation of water through sandy soils has carried soluble nitrate, a byproduct of fertilizer, into the ground-water reservoir.

Georgia↗