No abstract

A type‐curve method for determining anisotropy of unconfined aquifers, developed from electric analog simulation, is applied to drawdowns observed near, a well pumping from a glacial outwash aquifer at Piketon, Ohio. The coefficient of vertical permeability, P z'averaged 365 gpd per square foot. Computed drawdown for the pumped well, based on this value, differed by only a small amount from the observed drawdown. The coefficient of storage, determined from type curves for an image well system, averaged 0.20, typical of unconfined aquifers. Application of the method required a thorough knowledge of geohydrologic controls operating at the test site.

Altitude of drillers' "first water" zone (Oriskany Sandstone) (top map) and Newberg or "second water" zone (bottom map) in northeast Ohio 3 Aggregate thickness of salt, gypsum, and anhydrite beds greater than 10 feet thick in the Salina Formation in Michigan-4 geologic section in northern Michigan, showing occurrence of evaporites in the Salina Formation ii

The Black Hand Sandstone Member of the Cuyahoga Formation and associated aquifers of Mississippian age, including the Allensville Conglomerate, Member of the Logan Formation, were investigated in a 1,500-square-mile area, parts of five counties in southeastern Ohio. The aquifers crop out in western Vinton, western Hocking, and southwestern Fairfield Counties. They dip southeastward about 35 feet per mile, becoming progressively more deeply buried until at Lake Hope, in northeastern Vinton County, the aquifers are the deepest sources of potable ground water in Ohio, occurring at depths locally exceeding 700 feet. These aquifers are the chief sources of water beneath the coal-bearing rocks of the Pennsylvanian System and are widely used for farm and home requirements. Specific capacities of wells are low, exceeding 1 gallon per minute per foot of drawdown only in scattered areas. At McArthur, in Vinton County, the aquifers yield about 300,000 gallons per day for municipal and industrial use, but withdrawal has been accompanied by declining groundwater levels during the past 10 years in a 10-square-mile area. Transmissivity, determined from wells open to both the Black Hand Sandstone Member and Allensville Conglomerate Member at McArthur's west municipal well field, is about 135 square feet per day. The ground water is predominately of the sodium bicarbonate or calcium bicarbonate type in the central part of the area and changes, as it moves downdip, to a sodium chloride bicarbonate type. Along the eastern boundaries of Hocking and Vinton Counties, the aquifers are below the common depth of wells and are presumed to be potable but contain water too salty for ordinary use. Locally, the aquifers are contaminated by brine from oil and gas wells. The report is based largely on drillers' logs of domestic water wells in the files of the Division of Water, Ohio Department of Natural Resources. Approximately 350 logs were field located, of which 160 were selected as a data base. The selected wells are listed in table 3, and the logs are presented graphically in figure 18. The approximate locations of the wells are shown in figure 17. More precise locations can be obtained from Ohio Division of Water files, by reference to the State log number given in table 3.

No abstract