Geology topics

Linda L. Bobo

Publications and source records attributed to Linda L. Bobo.

3 recordsLinked to original sources

USGS1982

Hydrologic data collected in and around a surface coal mine, Clay and Vigo counties, Indiana, 1977-80

Few data are available for evaluating water-quality and other hydrologic properties in and around surface coal mines, particularly in areas where material having a high potential for acid-production is selectively buried. This report contains hydrologic data collected in an active coal mining area in Clay and Vigo Counties, Indiana, from September 1977 through February 1980. Methods of sampling and analysis used in collecting the data also are summarized. The data include field and laboratory measurements of water at 41 wells and 24 stream sites. Variables measured in the field include water temperature, specific conductance, pH, Eh, dissolved oxygen, ground-water levels, and streamflow; and in the laboratory, concentrations of major ions, alkalinity, hardness, trace elementsl, organic carbon, phosphorus, and dissolved solids. Other variables measured in the laboratory include ferrous iron concentration of water samples from selected wells, percent sulfur by weight and the potential acidity of core samples of reclaimed cast overburden, concentrations of elements absorbed on streambed materials, concentrations and particle size of suspended sediment in water, and populations and Shannon diversity indices of phytoplankton in water. Dissolved-solids concentrations and pH of ground water ranged from 173 to 5,130 milligrams per liter and from 6.1 to 8.9, respectively, and of surface water, from 120 to 4,100 milligrams per liter and from 6.1 to 8.8 respectively.

Indiana↗

USGS1980

Water-quality assessment of the Porter County watershed, Kankakee River basin, Porter County, Indiana

Water type in the 241-square mile Porter County watershed in Indiana, was calcium bicarbonate or mixed calcium bicarbonate and calcium sulfate. Concentrations of dissolved chemical constituents in surface water and contents of chlorinated hydrocarbons in streambed samples in the watershed were generally less than water-quality alert limits set by the U.S. Environmental Protection Agency, except in Crooked Creek. During sampling, this stream was affected by sewage, chlorinated hydrocarbons, and two chemical spills. Ranges of on-site field measurements were: specific conductance, from 102 to 1,060 micromhos per centimeter at 25 Celcius; water temperature, from 7.0 to 31.8 Celsius; pH, from 6.8 to 8.9; dissolved oxygen, from 2.5 to 14.9 milligrams per liter and from 27 to 148% saturation; and instantaneous discharge from 0 to 101 cubic feet per second. Concentrations of most dissolved-inorganic constituents (heavy metals and major ions) and dissolved solids did not vary significantly from one sampling period to the next at each site. Dissolved constituents whose concentrations varied significantly were iron, manganese, organic carbon, ammonia, nitrate plus nitrite, organic nitrogen, Kjeldahl nitrogen, and phosphorus. Concentrations of dissolved manganese, organic carbon, dissolved nitrite plus nitrate, and suspended sediment varied seasonally at most sites. Populations and identification of bacteria, phytoplankton, periphyton, and benthic invertebrates indicate a well-balanced environment at most sites, except in Crooked Creek.

Indiana↗

USGS1979

Gazetteer of coal-mine lakes in southwestern Indiana

This gazetteer is a catalog of lakes formed by surface coal mining in southwestern Indiana that are 0.5 acre or larger and in nonactive mine areas. Approximately 1,000 of the lakes are listed by 7.5-minute quadrangle topographic-map name, lake-identification number, latitude and longitude, and county. Other data given are shape of lake, maximum length, mean width, length and development of shoreline, surface area, orientation, presence of a stream inlet or outlet, and geologic data (geologic formation of area surrounding the lake and the mined coal-bed member). Field data (sampling date, pH, specific conductance, apparent color of lake, and general vegetation along the shoreline) were collected for 287 of the lakes. Two hundred eighty-seven lakes were sampled once for pH and specific conductance. Vegetation along the shoreline and apparent color of each lake were identified at the same time. Although these data are not sufficient to quantify the water quality of the lakes, they do illustrate the variability of these characteristics. The pH of the 287 lakes ranged from 2.5 to 10.0; however, the pH of 80 percent of them ranged from 6 to 9. Specific conductance ranged from 99 to 3,800 micromhos per centimeter at 25? Celsius. Specific conductance for approximately 70 percent of the lakes in the Staunton and Brazil formations was less than 500 micromhos per centimeter at 25? Celsius, but for approximately 65 percent in the Dugger and Petersburg Formations it was greater than 1,000 micromhos per centimeter at 25? Celsius. The apparent colors of the lakes observed were varying shades of aqua, blue, brown, lime green, red, and green. Eighty percent of the lakes sampled were green. Lake sizes ranged from a chosen minimum of 0.5 acre to a maximum of 344 acres. Maximum length ranged from 0.1 to 2 miles, and the mean width was generally less than 0.8 mile.

Open-File Report↗