Charles A Cravotta, III, PhD, PG (Former Employee)
Science and Products
Filter Total Items: 89
Acid-rock drainage at Skytop, Centre County, Pennsylvania, 2004
Recent construction for Interstate Highway 99 (I?99) exposed pyrite and associated Zn-Pb sulfide minerals beneath a >10-m thick gossan to oxidative weathering along a 40-60-m deep roadcut through a 270-m long section of the Ordovician Bald Eagle Formation at Skytop, near State College, Centre County, Pennsylvania. Nearby Zn-Pb deposits hosted in associated sandstone and limestone in Blair and Cent
Authors
Jane M. Hammarstrom, Keith Brady, Charles A. Cravotta
Net alkalinity and net acidity 1: Theoretical considerations
Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO2, and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to
Authors
C.S. Kirby, C.A. Cravotta
Net alkalinity and net acidity 2: Practical considerations
The pH, alkalinity, and acidity of mine drainage and associated waters can be misinterpreted because of the chemical instability of samples and possible misunderstandings of standard analytical method results. Synthetic and field samples of mine drainage having various initial pH values and concentrations of dissolved metals and alkalinity were titrated by several methods, and the results were com
Authors
C.S. Kirby, C.A. Cravotta
Implications of ground water chemistry and flow patterns for earthquake studies
Ground water can facilitate earthquake development and respond physically and chemically to tectonism. Thus, an understanding of ground water circulation in seismically active regions is important for earthquake prediction. To investigate the roles of ground water in the development and prediction of earthquakes, geological and hydrogeological monitoring was conducted in a seismogenic area in the
Authors
W. Guangcai, Z. Zuochen, W. Min, C.A. Cravotta, L. Chenglong
Acidity and alkalinity in mine drainage: Theoretical considerations
Acidity, net acidity, and net alkalinity are widely used parameters for the characterization of mine drainage, but these terms are not well defined and are often misunderstood. Incorrect interpretation of acidity, alkalinity, and derivative terms can lead to inadequate treatment design or poor regulatory decisions. We briefly explain derivations of theoretical expressions of three types of alkalin
Authors
Carl S. Kirby, Charles A. Cravotta
Acidity and Alkalinity in mine drainage: Practical considerations
In this paper, we emphasize that the Standard Method hot peroxide treatment procedure for acidity determination (hot acidity) directly measures net acidity or net alkalinity, but that more than one water-quality measure can be useful as a measure of the severity of acid mine drainage. We demonstrate that the hot acidity is related to the pH, alkalinity, and dissolved concentrations of Fe, Mn, and
Authors
Charles A. Cravotta, III, Carl S. Kirby
Effects of Abandoned Coal-Mine Drainage on Streamflow and Water Quality in the Mahanoy Creek Basin, Schuylkill, Columbia, and Northumberland Counties, Pennsylvania, 2001
This report assesses the contaminant loading, effects to receiving streams, and possible remedial alternatives for abandoned mine drainage (AMD) within the Mahanoy Creek Basin in east-central Pennsylvania. The Mahanoy Creek Basin encompasses an area of 157 square miles (407 square kilometers) including approximately 42 square miles (109 square kilometers) underlain by the Western Middle Anthracite
Authors
Charles A. Cravotta
Optimization of limestone drains for long- term treatment of acidic mine drainage, Swatara Creek Basin, Schuylkill County, PA
Limestone drains were constructed in 1995, 1997, and 2000 to treat acidic mine drainage (AMD) from the Orchard, Buck Mtn., and Hegins discharges, respectively, in the Swatara Creek Basin, Southern Anthracite Coalfield, east-central Pennsylvania. This report summarizes the construction characteristics and performance of each of the limestone drains on the basis of influent and effluent quality and
Authors
Charles A. Cravotta, S.J. Ward, Daniel J. Koury, R. D. Koch
Size and performance of anoxic limestone drains to neutralize acidic mine drainage
Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict
Authors
C.A. Cravotta
Effects of abandoned coal-mine drainage on streamflow and water quality in the Shamokin Creek Basin, Northumberland and Columbia Counties, Pennsylvania, 1999-2001
This report assesses the contaminant loading, effects to receiving streams, and possible remedial alternatives for abandoned mine drainage (AMD) within the upper Shamokin Creek Basin in east-central Pennsylvania. The upper Shamokin Creek Basin encompasses an area of 54 square miles (140 square kilometers) within the Western Middle Anthracite Field, including and upstream of the city of Shamokin. E
Authors
Charles A. Cravotta, Carl S. Kirby
Design and performance of limestone drains to increase pH and remove metals from acidic mine drainage, Chapter 2
Data on the construction characteristics and the composition of influent and effluent at 13 underground, limestone-filled drains in Pennsylvania and Maryland are reported to evaluate the design and performance of limestone drains for the attenuation of acidity and dissolved metals in acidic mine drainage. On the basis of the initial mass of limestone, dimensions of the drains, and average flow rat
Authors
Charles A. Cravotta, George R. Watzlaf
Use of stable isotopes of carbon, nitrogen, and sulfur to identify sources of nitrogen in surface waters in the lower Susquehanna River basin, Pennsylvania
With the exception of sewage and septic effluents, most nitrogen sources and soils contain larger proportions of organic and reduced forms of carbon, nitrogen, and sulfur than inorganic, oxidized forms. In contrast, most surface water and ground water contains larger proportions of dissolved inorganic carbon, nitrogen, and sulfur forms than organic forms. Data indicate that carbon, nitrogen, and s
Authors
Charles A. Cravotta
Science and Products
Filter Total Items: 89
Acid-rock drainage at Skytop, Centre County, Pennsylvania, 2004
Recent construction for Interstate Highway 99 (I?99) exposed pyrite and associated Zn-Pb sulfide minerals beneath a >10-m thick gossan to oxidative weathering along a 40-60-m deep roadcut through a 270-m long section of the Ordovician Bald Eagle Formation at Skytop, near State College, Centre County, Pennsylvania. Nearby Zn-Pb deposits hosted in associated sandstone and limestone in Blair and Cent
Authors
Jane M. Hammarstrom, Keith Brady, Charles A. Cravotta
Net alkalinity and net acidity 1: Theoretical considerations
Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO2, and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to
Authors
C.S. Kirby, C.A. Cravotta
Net alkalinity and net acidity 2: Practical considerations
The pH, alkalinity, and acidity of mine drainage and associated waters can be misinterpreted because of the chemical instability of samples and possible misunderstandings of standard analytical method results. Synthetic and field samples of mine drainage having various initial pH values and concentrations of dissolved metals and alkalinity were titrated by several methods, and the results were com
Authors
C.S. Kirby, C.A. Cravotta
Implications of ground water chemistry and flow patterns for earthquake studies
Ground water can facilitate earthquake development and respond physically and chemically to tectonism. Thus, an understanding of ground water circulation in seismically active regions is important for earthquake prediction. To investigate the roles of ground water in the development and prediction of earthquakes, geological and hydrogeological monitoring was conducted in a seismogenic area in the
Authors
W. Guangcai, Z. Zuochen, W. Min, C.A. Cravotta, L. Chenglong
Acidity and alkalinity in mine drainage: Theoretical considerations
Acidity, net acidity, and net alkalinity are widely used parameters for the characterization of mine drainage, but these terms are not well defined and are often misunderstood. Incorrect interpretation of acidity, alkalinity, and derivative terms can lead to inadequate treatment design or poor regulatory decisions. We briefly explain derivations of theoretical expressions of three types of alkalin
Authors
Carl S. Kirby, Charles A. Cravotta
Acidity and Alkalinity in mine drainage: Practical considerations
In this paper, we emphasize that the Standard Method hot peroxide treatment procedure for acidity determination (hot acidity) directly measures net acidity or net alkalinity, but that more than one water-quality measure can be useful as a measure of the severity of acid mine drainage. We demonstrate that the hot acidity is related to the pH, alkalinity, and dissolved concentrations of Fe, Mn, and
Authors
Charles A. Cravotta, III, Carl S. Kirby
Effects of Abandoned Coal-Mine Drainage on Streamflow and Water Quality in the Mahanoy Creek Basin, Schuylkill, Columbia, and Northumberland Counties, Pennsylvania, 2001
This report assesses the contaminant loading, effects to receiving streams, and possible remedial alternatives for abandoned mine drainage (AMD) within the Mahanoy Creek Basin in east-central Pennsylvania. The Mahanoy Creek Basin encompasses an area of 157 square miles (407 square kilometers) including approximately 42 square miles (109 square kilometers) underlain by the Western Middle Anthracite
Authors
Charles A. Cravotta
Optimization of limestone drains for long- term treatment of acidic mine drainage, Swatara Creek Basin, Schuylkill County, PA
Limestone drains were constructed in 1995, 1997, and 2000 to treat acidic mine drainage (AMD) from the Orchard, Buck Mtn., and Hegins discharges, respectively, in the Swatara Creek Basin, Southern Anthracite Coalfield, east-central Pennsylvania. This report summarizes the construction characteristics and performance of each of the limestone drains on the basis of influent and effluent quality and
Authors
Charles A. Cravotta, S.J. Ward, Daniel J. Koury, R. D. Koch
Size and performance of anoxic limestone drains to neutralize acidic mine drainage
Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict
Authors
C.A. Cravotta
Effects of abandoned coal-mine drainage on streamflow and water quality in the Shamokin Creek Basin, Northumberland and Columbia Counties, Pennsylvania, 1999-2001
This report assesses the contaminant loading, effects to receiving streams, and possible remedial alternatives for abandoned mine drainage (AMD) within the upper Shamokin Creek Basin in east-central Pennsylvania. The upper Shamokin Creek Basin encompasses an area of 54 square miles (140 square kilometers) within the Western Middle Anthracite Field, including and upstream of the city of Shamokin. E
Authors
Charles A. Cravotta, Carl S. Kirby
Design and performance of limestone drains to increase pH and remove metals from acidic mine drainage, Chapter 2
Data on the construction characteristics and the composition of influent and effluent at 13 underground, limestone-filled drains in Pennsylvania and Maryland are reported to evaluate the design and performance of limestone drains for the attenuation of acidity and dissolved metals in acidic mine drainage. On the basis of the initial mass of limestone, dimensions of the drains, and average flow rat
Authors
Charles A. Cravotta, George R. Watzlaf
Use of stable isotopes of carbon, nitrogen, and sulfur to identify sources of nitrogen in surface waters in the lower Susquehanna River basin, Pennsylvania
With the exception of sewage and septic effluents, most nitrogen sources and soils contain larger proportions of organic and reduced forms of carbon, nitrogen, and sulfur than inorganic, oxidized forms. In contrast, most surface water and ground water contains larger proportions of dissolved inorganic carbon, nitrogen, and sulfur forms than organic forms. Data indicate that carbon, nitrogen, and s
Authors
Charles A. Cravotta
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