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G. R. Schiner

Publications and source records attributed to G. R. Schiner.

12 recordsLinked to original sources
USGS1988

Geohydrology of Indian River County, Florida

The surficial aquifer system and the Floridan aquifer system are the sources of groundwater used in Indian River County, Florida. About 65% of the groundwater is used for irrigation and is from the Floridan aquifer system. Saline water ranging from slightly saline to brine underlies the fresh groundwater throughout the county and is the chief water quality problem. Transmissivities of the surficial aquifer system in eastern Indian River County range from 1,500 to 11,000 sq ft/d. Yields of wells are as much as 1,200 gal/min. Reported transmissivities for the Floridan aquifer system range from 65,000 to 200,000 sq ft/d. Most wells that tap the Floridan aquifer system flow; flow rates range from 30 to 2,000 gal/min. Chloride concentrations of water in the surficial aquifer system generally are below 100 mg/L, but concentrations often exceed 250 mg/L in water from the Floridan aquifer system. Between 1976 and 1983, average chloride concentrations in water from six wells that tap the surficial aquifer system in the Vero Beach well field increased about 36 mg/L, but were unchanged in four other wells. The increase in chloride concentration probably is related to a well-field pumpage increase from 5.44 million gal/d in 1976 to 8.00 million gal/d in 1983. In most of the County, chloride concentrations of wells that tap the Floridan aquifer system have not changed significantly in the 15-year period, 1968-83. Water levels in the surficial aquifer system declined 15 to 19 ft between 1971 and 1984 in the Vero Beach well field where the larger groundwater withdrawals occur, but have not declined significantly outside heavily pumped areas. Water levels in the Floridan aquifer system have declined 16 to 24 ft in eastern Indian River County in the 50-year period, 1934-84, but declines outside the heavily pumped areas generally have been less than 10 ft during this period. (USGS)

Water-Resources Investigations Report↗
USGS1983

Effects of recharge from drainage wells on quality of water in the Floridan Aquifer in the Orlando area, central Florida

Approximately 400 drainage wells in the Orlando area inject, by gravity, large quantities of stormwater runoff that may or may not be suitable for most purposes without treatment into the same freshwater zones of the Floridan aquifer tapped for public supply. The wells are used mostly to control lake levels and dispose of urban storm runoff. Recharge from drainage wells compensates for heavy withdrawals from the Floridan aquifer and helps maintain aquifer pressures that retard upward saltwater encroachment. Sixty-five supply wells and 21 drainage wells within a 16-mile radius of Orlando were sampled from September 1977 to June 1979. Most constituent concentrations were slightly higher in water from drainage wells than in water from supply wells. The most notable differences were in bacteria colony count and total nitrogen concentrations. With the exception of bacteria, water from drainage wells would generally meet the maximum contaminant levels established by the National Interim Primary and Proposed Secondary Drinking Water Regulations. (USGS)

Water-Resources Investigations Report↗
USGS1981

Water resources of the Clarion River and Redbank Creek basins, northwestern Pennsylvania

The Clarion River and Redbank Creek basin occupy 1,280 and 545 square miles, respectively, in northwatern Pennsylvania. The area is mostly in Clerion, Elk, and Jefferson Counties and is approximately 70 miles long and 30 miles wide. All drainage is to the Allegheny River. Sedimentary rocks of Late Devionian Early Mississippian, and Pennsylvanian age underlie the area. Rocks of Late Devonian age underlie the entire area and crop out in the deep stream valleys in the north. Lower Mississippian rocks generally crop out in strips along major stream valleys; the strips are narrow in the south and broaden northward. Pennsylvanian rocks cover most of the interfluvial areas between major streams. The Upper Devonian and Lower Mississippian rocks are composed mostly of alternating sandstone and shale. Sandstone may intertongue laterally with shale. The Pennsylvanian rocks are most heterogeneous and contain many commercial coal beds. The major mineral resources are bituminous coal, petroleum, and natural gas. Narly all coal production is from strip mining in Clarion, Elk, and Jefferson Counties. Total coal production exceeded 8 million short tons in 1976. The basins are south and east of the major oil-producing regions in Pennsylvania, but more than 50,000 barrels of crude oil were produced here in 1975. Commercial quantities of natural gas are also obtained. Thirty-three public water-supply systems furnish about two-thirds of the water for domestic use. Surface water is the source of about 90 percent of public-supply water. The remainder is from wells and springs. In an average year, 64 percent of the precipitation in the Clarion River basin and 60 percent in the Redbank Creek basin leave the area as streamflow. The percentage of annuual discharge from each basin that is base runoff averaged 53 and 51 percent, respectively, during 1972-75. Only 4 of 10 stream-gaging stations recorded an average 10-year, 7-consecutive day low flow of at least 0.15 cubic feet per second per square mile. Most wells are completed on bedrock. Yields of bedrock wells are affected mostly by rock type, type of overburden, topography, depth of water-bearing zones, and by the rate and duration of pumping. Water in the bedrock occurs chiefly along fractures and bedding planes. Most wells get water from several zones. Yielding zones occur less frequently as depth increases, but are reported as much as 400 feet below land surface. Optimum well depth is about 350 feet. Well yields range from less than 1 to more than 550 gallons per minute. The best bedrock aquifers are the Lower Mississippian rocks, which have a median specific capacity of 4.3 gallons per minute per foot of drawdown compared to median between 0.38 and 0.67 in the Conemaugh, Allegheny, and Pottsville Groups. The major water-qualitty problems are due to high concentrations of iron, manganese, hardness, and acidity. Some of these problems are related to coal mining that has degraded water quality in parts of Clarion, Clearfield, Elk, and Jefferson Counties. Water-quality problems result from the rock composition. Many streams have low alkalinity concentrations and, consequently, have little capacity to neutralize the acid water from coal mines. Large forested areas, with little development, in Elk, Forest, and Jefferson Counties, have good quality water. The water from over three-quarters of the bedrock wells sampled has dissolved-solids concentratins less than 250 milligrams per liter. Water from aqufers of Pennsylvanian age is generally lower in dissolved solids than that from Lower Mississippian aquifers. Salt water is not a problem, except locally in Devonian rocks. Water from wells on hilltops is generally of better quality than that from wells in valleys (median dissolved solids 140 versus 340 millgrams per liter). In many valleys in Clarion and Jefferson Counties, old abandoned flowing oil and gas wells contribute high

Open-File Report↗
USGS1981

Potentiometric surface of the Floridan aquifer, southwest Florida Water Management District, September 1981

A September 1981 potentiometric-surface map of the Southwest Florida Water Management District depicts the annual high water-level period. Water levels in most wells measured in September 1981 are equal to or higher than in May 1981. Levels averaged about 26 feet higher in the southern part of the area and 5 feet in the north. In the agricultural sections of southern Hillsborough, Hardee, southwestern Polk, northwestern De Soto, and Manatee Counties, water levels increased 10 to 46 feet. From September 1980 to September 1981, water levels ranged from a decrease of 11 feet in Citrus County to an increase of 9 feet in southern Hillsborough County. (USGS)

Florida↗
USGS1976

Geology and ground-water resources of northern Mercer County, Pennsylvania

The Shenango and Stoneboro 15-minute quadrangles are in northwestern Pennsylvania and are about 60 miles north of Pitts burgh. These two quadrangles comprise the following 7%-minute quadrangles: Greenville West, Greenville East, Sharpsville, Fredonia, Hadley, New Lebanon, Jackson Center, and Sandy Lake. The area covered by the two quadrangles includes the northern two thirds of Mercer County and a small amount of adjoining southern Crawford County.

Pennsylvania↗