Charles A Cravotta, III, PhD, PG (Former Employee)
Science and Products
Filter Total Items: 94
The quality of our nation's waters: water quality in the Principal Aquifers of the Piedmont, Blue Ridge, and Valley and Ridge regions, eastern United States, 1993-2009 The quality of our nation's waters: water quality in the Principal Aquifers of the Piedmont, Blue Ridge, and Valley and Ridge regions, eastern United States, 1993-2009
The aquifers of the Piedmont, Blue Ridge, and Valley and Ridge regions underlie an area with a population of more than 40 million people in 10 states. The suburban and rural population is large, growing rapidly, and increasingly dependent on groundwater as a source of supply, with more than 550 million gallons per day withdrawn from domestic wells for household use. Water from some of...
Authors
Bruce D. Lindsey, Tammy M. Zimmerman, Melinda J. Chapman, Charles A. Cravotta, Zoltan Szabo
Spectral masking of goethite in abandoned mine drainage systems: implications for Mars Spectral masking of goethite in abandoned mine drainage systems: implications for Mars
Remote sensing studies of the surface of Mars use visible- to near-infrared (VNIR) spectroscopy to identify hydrated and hydroxylated minerals, which can be used to constrain past environmental conditions on the surface of Mars. However, due to differences in optical properties, some hydrated phases can mask others in VNIR spectra, complicating environmental interpretations. Here, we...
Authors
Selby Cull, Charles A. Cravotta, Julia Grace Klinges, Chloe Weeks
Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008 Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008
Groundwater quality and aquifer lithologies in the Piedmont and Blue Ridge Physiographic Provinces in the eastern United States vary widely as a result of complex geologic history. Bedrock composition (mineralogy) and geochemical conditions in the aquifer directly affect the occurrence (presence in rock and groundwater) and distribution (concentration and mobility) of potential naturally...
Authors
Melinda J. Chapman, Charles A. Cravotta, Zoltan Szabo, Bruce D. Lindsay
Surface-water and groundwater interactions in an extensively mined watershed, upper Schuylkill River, Pennsylvania, USA Surface-water and groundwater interactions in an extensively mined watershed, upper Schuylkill River, Pennsylvania, USA
Streams crossing underground coal mines may lose flow, while abandoned mine drainage (AMD) restores flow downstream. During 2005-12, discharge from the Pine Knot Mine Tunnel, the largest AMD source in the upper Schuylkill River Basin, had near-neutral pH and elevated concentrations of iron, manganese, and sulfate. Discharge from the tunnel responded rapidly to recharge but exhibited a...
Authors
Charles A. Cravotta, Daniel J. Goode, Michael D. Bartles, Dennis W. Risser, Daniel G. Galeone
Inhibition of bacterial oxidation of ferrous iron by lead nitrate in sulfate-rich systems Inhibition of bacterial oxidation of ferrous iron by lead nitrate in sulfate-rich systems
Inhibition of bacterial oxidation of ferrous iron (Fe(II)) by Pb(NO3)2 was investigated with a mixed culture of Acidithiobacillus ferrooxidans. The culture was incubated at 30 °C in ferrous-sulfate medium amended with 0–24.2 mM Pb(II) added as Pb(NO3)2. Anglesite (PbSO4) precipitated immediately upon Pb addition and was the only solid phase detected in the abiotic controls. Both...
Authors
Hongmei Wang, Linfeng Gong, Charles A. Cravotta, Xiaofen Yang, Olli H. Tuovinen, Hailiang Dong, Xiang Fu
Evolution of the chemistry of Fe bearing waters during CO2 degassing Evolution of the chemistry of Fe bearing waters during CO2 degassing
The rates of Fe(II) oxidation and precipitation from groundwater are highly pH dependent. Elevated levels of dissolved CO2 can depress pH and cause difficulty in removing dissolved Fe and associated metals during treatment of ferruginous water. This paper demonstrates interdependent changes in pH, dissolved inorganic C species, and Fe(II) oxidation rates that occur as a result of the...
Authors
J.N. Geroni, C.A. Cravotta, D.J. Sapsford
Science and Products
Filter Total Items: 94
The quality of our nation's waters: water quality in the Principal Aquifers of the Piedmont, Blue Ridge, and Valley and Ridge regions, eastern United States, 1993-2009 The quality of our nation's waters: water quality in the Principal Aquifers of the Piedmont, Blue Ridge, and Valley and Ridge regions, eastern United States, 1993-2009
The aquifers of the Piedmont, Blue Ridge, and Valley and Ridge regions underlie an area with a population of more than 40 million people in 10 states. The suburban and rural population is large, growing rapidly, and increasingly dependent on groundwater as a source of supply, with more than 550 million gallons per day withdrawn from domestic wells for household use. Water from some of...
Authors
Bruce D. Lindsey, Tammy M. Zimmerman, Melinda J. Chapman, Charles A. Cravotta, Zoltan Szabo
Spectral masking of goethite in abandoned mine drainage systems: implications for Mars Spectral masking of goethite in abandoned mine drainage systems: implications for Mars
Remote sensing studies of the surface of Mars use visible- to near-infrared (VNIR) spectroscopy to identify hydrated and hydroxylated minerals, which can be used to constrain past environmental conditions on the surface of Mars. However, due to differences in optical properties, some hydrated phases can mask others in VNIR spectra, complicating environmental interpretations. Here, we...
Authors
Selby Cull, Charles A. Cravotta, Julia Grace Klinges, Chloe Weeks
Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008 Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008
Groundwater quality and aquifer lithologies in the Piedmont and Blue Ridge Physiographic Provinces in the eastern United States vary widely as a result of complex geologic history. Bedrock composition (mineralogy) and geochemical conditions in the aquifer directly affect the occurrence (presence in rock and groundwater) and distribution (concentration and mobility) of potential naturally...
Authors
Melinda J. Chapman, Charles A. Cravotta, Zoltan Szabo, Bruce D. Lindsay
Surface-water and groundwater interactions in an extensively mined watershed, upper Schuylkill River, Pennsylvania, USA Surface-water and groundwater interactions in an extensively mined watershed, upper Schuylkill River, Pennsylvania, USA
Streams crossing underground coal mines may lose flow, while abandoned mine drainage (AMD) restores flow downstream. During 2005-12, discharge from the Pine Knot Mine Tunnel, the largest AMD source in the upper Schuylkill River Basin, had near-neutral pH and elevated concentrations of iron, manganese, and sulfate. Discharge from the tunnel responded rapidly to recharge but exhibited a...
Authors
Charles A. Cravotta, Daniel J. Goode, Michael D. Bartles, Dennis W. Risser, Daniel G. Galeone
Inhibition of bacterial oxidation of ferrous iron by lead nitrate in sulfate-rich systems Inhibition of bacterial oxidation of ferrous iron by lead nitrate in sulfate-rich systems
Inhibition of bacterial oxidation of ferrous iron (Fe(II)) by Pb(NO3)2 was investigated with a mixed culture of Acidithiobacillus ferrooxidans. The culture was incubated at 30 °C in ferrous-sulfate medium amended with 0–24.2 mM Pb(II) added as Pb(NO3)2. Anglesite (PbSO4) precipitated immediately upon Pb addition and was the only solid phase detected in the abiotic controls. Both...
Authors
Hongmei Wang, Linfeng Gong, Charles A. Cravotta, Xiaofen Yang, Olli H. Tuovinen, Hailiang Dong, Xiang Fu
Evolution of the chemistry of Fe bearing waters during CO2 degassing Evolution of the chemistry of Fe bearing waters during CO2 degassing
The rates of Fe(II) oxidation and precipitation from groundwater are highly pH dependent. Elevated levels of dissolved CO2 can depress pH and cause difficulty in removing dissolved Fe and associated metals during treatment of ferruginous water. This paper demonstrates interdependent changes in pH, dissolved inorganic C species, and Fe(II) oxidation rates that occur as a result of the...
Authors
J.N. Geroni, C.A. Cravotta, D.J. Sapsford
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