Charles A Cravotta, III, PhD, PG (Former Employee)
Science and Products
Phosphorus in the Susquehanna River may be tied to legacy sediment and changing pH
The Susquehanna River is the predominant source of freshwater and nutrients entering the Chesapeake Bay.
Regional Synthesis of Groundwater Quality in Domestic Supply Wells in Northeast and North Central Pennsylvania
USGS synthesized groundwater quality measurements in wells to characterize regional chemical characteristics of aquifers used for domestic supply in northeast and north central Pennsylvania.
Groundwater Quality of Domestic Supply Wells in Pennsylvania
Most rural residents in Pennsylvania use groundwater from domestic supply wells for drinking, cleaning and other purposes. Some groundwater samples have been analyzed for private purposes, but those results generally are not readily available to the public. Many of the publicly available water-quality samples from rural areas were collected more than 30 years ago. Quality-assured groundwater...
Recoding of AMDTreat Phase 2: Integration of PHREEQ-N-AMDTreat water-quality prediction tools with recoded AMDTreat cost-analysis software
Newly developed PHREEQ-N-AMDTreat water-quality prediction tools indicate potential changes in pH, dissolved metals, and associated solute concentrations resulting from passive and active treatment of coal-mine drainage.
Mine Drainage and Water Quality Research
The USGS Pennsylvania Water Science Center conducts research on geochemical and hydrological processes that control water quality, including the sources, transport, and attenuation of metals and nutrients in undisturbed and mining-impacted watersheds and aquifers. Results apply to scientific and regulatory programs for the prevention and remediation of aquatic contamination.
Coal mine drainage effluents and associated solids major, trace, rare earth element and radium concentrations collected from Pennsylvania, USA
Discharges from abandoned coal mines and associated mine wastes represent historic and persistent sources of pollution in the Appalachian Basin, United States. In this study, we conducted the first-ever survey of radium (Ra) in coal mine drainage (CMD) water and solid samples in the United States. Samples were collected from 4 untreated coal mine discharges and 9 treated coal mine...
Salinity and total dissolved solid determinations using PHREEQCI
The total concentration of dissolved constituents in water is routinely quantified by measurements of salinity or total dissolved solids (TDS). However, salinity and TDS are operationally defined by their analytical methods and are not equivalent for most waters. Furthermore, multiple methods are available to determine salinity and TDS, and these methods have inherent differences. TDS is...
Data compilation for regional synthesis of chemical characteristics of groundwater used for domestic supply in north-east and north-central Pennsylvania
Groundwater quality data for 472 domestic well-water samples were retrieved from the USGS National Water Information System (NWIS) database and combined with descriptive information on the sampled well locations. The NWIS data for a sample, collected on the selected date, were averaged into a single record (one per well), and rounded according to USGS protocols. For evaluation and...
Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018
Lithium concentrations in untreated groundwater from 1,464 public-supply wells, 1,676 domestic-supply wells, and 1,560 monitoring wells distributed across 33 principal aquifers in the United States were evaluated for spatial variations and possible explanatory factors. For context, lithium concentrations are compared to a drinking-water only threshold (60 mg/L) and a Health-Based...
Compilation of data not available in the National Water Information System for domestic wells sampled by the U.S. Geological Survey in Clinton County, Pennsylvania, May-September 2017
This dataset contains the lithologic class and topographic position index information and quality-assurance and quality-control data not available in the online National Water Information System for 54 domestic wells sampled by the U.S. Geological Survey in Clinton County, Pennsylvania, May-September 2017. The topographic position index (TPI) for each well location was computed on the...
Hydrologic data collected by the U.S. Geological Survey and National Park Service at the Allegheny Portage Railroad National Historic Site, Summit Area, Blair and Cambria Counties, Pennsylvania, April 2014-December 2016
This data release reports water-quantity and water-quality data collected during 2014-2016 by the U.S. Geological Survey (USGS) and in cooperation with the National Park Service (NPS) at the Allegheny Portage Railroad National Historic Site (ALPO) in Blair and Cambria Counties, Pennsylvania (figure 1). These data establish a base-line for current hydrologic conditions and may be helpful...
Compilation of data not available in the National Water Information System for domestic wells sampled by the U.S. Geological Survey in Bradford County, Pennsylvania, May-August 2016
This dataset contains the lithologic class and topographic position index information and quality-assurance and quality-control data not available in the online National Water Information System for 72 domestic wells sampled by the U.S. Geological Survey in Bradford County, Pennsylvania, May-August 2016. The topographic position index (TPI) for each well location was computed on the...
Filter Total Items: 90
Exploring spatial and temporal symptoms of the freshwater salinization syndrome in a rural to urban watershed
The freshwater salinization syndrome (FSS), a concomitant watershed-scale increase in salinity, alkalinity, and major-cation and trace-metal concentrations, over recent decades, has been described for major rivers draining extensive urban areas, yet few studies have evaluated temporal and spatial FSS variations, or causal factors, at the subwatershed scale in mixed-use landscapes. This...
Authors
Nicole K. Marks, Charles A. Cravotta, Marissa Lee Rossi, Camila Silva, Peleg Kremer, Steven T. Goldsmith
Complex hydrology and variability of nitrogen sources in a karst watershed
Streams draining karst areas with rapid groundwater transit times may respond relatively quickly to nitrogen reduction strategies, but the complex hydrologic network of interconnected sinkholes and springs is challenging for determining the placement and effectiveness of management practices. This study aims to inform nitrogen reduction strategies in a representative agricultural karst...
Authors
John Clune, Charles A. Cravotta, Admin Husic, Hilary J Dozier, Kurt Eric Schmidt
Legacy sediment as a potential source of orthophosphate: Preliminary conceptual and geochemical models for the Susquehanna River, Chesapeake Bay watershed, USA
Nutrient pollution from agriculture and urban areas plus acid mine drainage (AMD) from legacy coal mines are primary causes of water-quality impairment in the Susquehanna River, which is the predominant source of freshwater and nutrients entering the Chesapeake Bay. Recent increases in the delivery of dissolved orthophosphate (PO4) from the river to the bay may be linked to long-term...
Authors
Charles A. Cravotta, Travis L. Tasker, Peter M. Smyntek, Joel Blomquist, John Clune, Qian Zhang, Noah Schmadel, Natalie Katrina Schmer
Determination and prediction of micro scale rare earth element geochemical associations in mine drainage treatment wastes
Acid mine drainage (AMD) has been proposed as a novel source of rare earth elements (REE), a group of elements that includes critical metals for clean energy and modern technologies. REE are sequestered in the Fe–Al–Mn-rich precipitates produced during the treatment of AMD. These AMD solids are typically managed as waste but could be a REE source. Here, results from AMD solids...
Authors
Benjamin C. Hedin, Mengling Y. Stuckman, Charles A. Cravotta, Christina L. Lopano, Rosemary C. Capo
Land development and road salt usage drive long-term changes in major-ion chemistry of streamwater in six exurban and suburban watersheds, southeastern Pennsylvania, 1999-2019
In urbanized areas, the “freshwater salinization syndrome” (FSS), which pertains to long-term increases in concentrations of major ions and metals in fresh surface waters, has been attributed to road salt application. In addition to FSS, the water composition changes as an influx of sodium (Na+) in recharge may displace calcium (Ca2+), magnesium (Mg2+), potassium (K+), and trace metals...
Authors
Marissa Lee Rossi, Peleg Kremer, Charles A. Cravotta, Krista E. Seng, Steven T. Goldsmith
Salinity and total dissolved solids measurements for natural waters: An overview and a new salinity method based on specific conductance and water type
The total concentration of dissolved constituents in water is routinely quantified by measurements of salinity or total dissolved solids (TDS). However, salinity and TDS are operationally defined by their analytical methods and are not equivalent for most waters. Furthermore, multiple methods are available to determine salinity and TDS, and these methods have inherent differences. TDS is...
Authors
R. Blaine McCleskey, Charles A. Cravotta, Matthew P. Miller, Fred D. Tillman, Paul Stackelberg, Katherine J. Knierim, Daniel Wise
Gross alpha-particle activity and high 226Ra concentrations do not correspond with high 210Po in the Atlantic and Gulf Coastal Plain aquifers of the United States
210Po, which is of human-health concern based on lifetime ingestion cancer risk, is indirectly regulated in drinking water through the U.S. Environmental Protection Agency’s gross alpha-particle activity (GAPA) maximum contaminant level of 15 pCi/L (picocuries per liter). This regulation requires independent measurement of 226Ra for samples exceeding the GAPA screening level of 5 pCi/L...
Authors
Zoltan Szabo, Charles A. Cravotta, Paul Stackelberg, Kenneth Belitz
Determination and prediction of rare earth element eeochemical associations in acid mine drainage treatment wastes
Acid mine drainage (AMD) has been proposed by various researchers as a novel source of rare earth elements (REE), a group of elements that include critical metals for clean energy and modern technologies. REE tend to be sequestered in the Fe-Al-Mn-rich solids produced during the treatment of AMD. These solids are typically managed as waste, but could be a low-cost, readily available REE...
Authors
B.C. Hedin, Charles A. Cravotta, M.Y. Stuckman, C.L. Lopano, R.C. Capo, R.S. Hedin
PHREEQ-N-AMDTreat+REYs water-quality modeling tools to evaluate acid mine drainage treatment strategies for recovery of rare-earth elements
The PHREEQ-N-AMDTreat+REYs water-quality modeling tools have the fundamental capability to simulate aqueous chemical reactions and predict the formation of metal-rich solids during the treatment of acid mine drainage (AMD). These new user-friendly, publicly available tools were expanded from the PHREEQ-N-AMDTreat tools to include the precipitation of rare-earth elements plus yttrium...
Authors
Charles A. Cravotta
Long-term impacts of impervious surface cover change and roadway deicing agent application on chloride concentrations in exurban and suburban watersheds
Roadway deicing agents, including rock salt and brine containing NaCl, have had a profound impact on the water quality and aquatic health of rivers and streams in urbanized areas with temperate climates. Yet, few studies evaluate impacts to watersheds characterized by relatively low impervious surface cover (ISC; 15 %). Here, we use long-term (1997-2019), monthly streamwater quality...
Authors
Marissa L. Rossi, Peleg Kremer, Charles A. Cravotta, Krista E. Scheirer, Steven T. Goldsmith
Pollutant co-attenuation via in-stream interactions between mine drainage and municipal wastewater
Municipal wastewater (MWW) and mine drainage (MD) are common co-occurring sources of freshwater pollution in mining regions. The physicochemical interactions that occur after mixing MWW and MD in a waterway may improve downstream water quality of an impaired reach by reducing downstream concentrations of nutrients and metals (i.e., “co-attenuation”). A first-order stream (Bradley Run in...
Authors
Charles J. Spellman, Peter M. Smyntek, Charles A. Cravotta, Travis L. Tasker, William H. J. Strosnider
Mine drainage precipitates attenuate and conceal wastewater-derived phosphate pollution in stream water
Hydrous ferric-oxide (HFO) coatings on streambed sediments may attenuate dissolved phosphate (PO4) concentrations at acidic to neutral pH conditions, limiting phosphorus (P) transport and availability in aquatic ecosystems. Mesh-covered tiles on which “natural” HFO from abandoned mine drainage (AMD) had precipitated were exposed to treated municipal wastewater (MWW) effluent or a mixture...
Authors
Peter M. Smyntek, Natalie Lamagna, Charles A. Cravotta, William H. J. Strosnider
Interactive PHREEQ-N-AMDTreat+REYs water-quality modeling tools to evaluate potential attenuation of rare-earth elements and associated dissolved constituents by aqueous-solid equilibrium processes (software download)
Software utilizing PHREEQC with user interface. The PHREEQ-N-AMDTreat+REYs geochemical modeling tools have the fundamental capability to simulate and predict key reactions related to the treatment of acid mine drainage and the formation of treatment solids, including the adsorption of rare-earth elements plus yttrium (REYs) onto hydrous iron, aluminum, and manganese oxides. These new...
Interactive PHREEQ-N-Titration-PO4-Adsorption water-quality modeling tools to evaluate potential attenuation of phosphate and associated dissolved constituents by aqueous-solid equilibrium processes (software download)
Two complementary executable water-quality modeling tools (CausticTitration_PO4mg.exe, CausticTitration_PO4moles.exe) simulate equilibrium processes that may attenuate dissolved concentrations of phosphate (PO4) plus associated concentrations of iron (Fe), aluminum (Al), manganese (Mn), calcium (Ca), and sulfate (SO4) as pH and other solution characteristics change during titration with...
PHREEQ-N-AMDTreat
USGS developed, in cooperation with the Office of Surface Mining Reclamation and Enforcement, “user-friendly” aqueous geochemical modeling tools to simulate changes in water quality during passive and active treatment of acid mine drainage.
Interactive PHREEQ-N-AMDTreat Water-Quality Modeling Tools to Evaluate Performance and Design of Treatment Systems for Acid Mine Drainage (software download)
The PHREEQ-N-AMDTreat aqueous geochemical modeling tools described herein simulate changes in pH and solute concentrations resulting from passive and active treatment of acidic or alkaline mine drainage (AMD). The “user-friendly” interactive tools, which are publicly available software, utilize PHREEQC equilibrium aqueous and surface speciation models and kinetics models for O2 ingassing...
Science and Products
Phosphorus in the Susquehanna River may be tied to legacy sediment and changing pH
The Susquehanna River is the predominant source of freshwater and nutrients entering the Chesapeake Bay.
Regional Synthesis of Groundwater Quality in Domestic Supply Wells in Northeast and North Central Pennsylvania
USGS synthesized groundwater quality measurements in wells to characterize regional chemical characteristics of aquifers used for domestic supply in northeast and north central Pennsylvania.
Groundwater Quality of Domestic Supply Wells in Pennsylvania
Most rural residents in Pennsylvania use groundwater from domestic supply wells for drinking, cleaning and other purposes. Some groundwater samples have been analyzed for private purposes, but those results generally are not readily available to the public. Many of the publicly available water-quality samples from rural areas were collected more than 30 years ago. Quality-assured groundwater...
Recoding of AMDTreat Phase 2: Integration of PHREEQ-N-AMDTreat water-quality prediction tools with recoded AMDTreat cost-analysis software
Newly developed PHREEQ-N-AMDTreat water-quality prediction tools indicate potential changes in pH, dissolved metals, and associated solute concentrations resulting from passive and active treatment of coal-mine drainage.
Mine Drainage and Water Quality Research
The USGS Pennsylvania Water Science Center conducts research on geochemical and hydrological processes that control water quality, including the sources, transport, and attenuation of metals and nutrients in undisturbed and mining-impacted watersheds and aquifers. Results apply to scientific and regulatory programs for the prevention and remediation of aquatic contamination.
Coal mine drainage effluents and associated solids major, trace, rare earth element and radium concentrations collected from Pennsylvania, USA
Discharges from abandoned coal mines and associated mine wastes represent historic and persistent sources of pollution in the Appalachian Basin, United States. In this study, we conducted the first-ever survey of radium (Ra) in coal mine drainage (CMD) water and solid samples in the United States. Samples were collected from 4 untreated coal mine discharges and 9 treated coal mine...
Salinity and total dissolved solid determinations using PHREEQCI
The total concentration of dissolved constituents in water is routinely quantified by measurements of salinity or total dissolved solids (TDS). However, salinity and TDS are operationally defined by their analytical methods and are not equivalent for most waters. Furthermore, multiple methods are available to determine salinity and TDS, and these methods have inherent differences. TDS is...
Data compilation for regional synthesis of chemical characteristics of groundwater used for domestic supply in north-east and north-central Pennsylvania
Groundwater quality data for 472 domestic well-water samples were retrieved from the USGS National Water Information System (NWIS) database and combined with descriptive information on the sampled well locations. The NWIS data for a sample, collected on the selected date, were averaged into a single record (one per well), and rounded according to USGS protocols. For evaluation and...
Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018
Lithium concentrations in untreated groundwater from 1,464 public-supply wells, 1,676 domestic-supply wells, and 1,560 monitoring wells distributed across 33 principal aquifers in the United States were evaluated for spatial variations and possible explanatory factors. For context, lithium concentrations are compared to a drinking-water only threshold (60 mg/L) and a Health-Based...
Compilation of data not available in the National Water Information System for domestic wells sampled by the U.S. Geological Survey in Clinton County, Pennsylvania, May-September 2017
This dataset contains the lithologic class and topographic position index information and quality-assurance and quality-control data not available in the online National Water Information System for 54 domestic wells sampled by the U.S. Geological Survey in Clinton County, Pennsylvania, May-September 2017. The topographic position index (TPI) for each well location was computed on the...
Hydrologic data collected by the U.S. Geological Survey and National Park Service at the Allegheny Portage Railroad National Historic Site, Summit Area, Blair and Cambria Counties, Pennsylvania, April 2014-December 2016
This data release reports water-quantity and water-quality data collected during 2014-2016 by the U.S. Geological Survey (USGS) and in cooperation with the National Park Service (NPS) at the Allegheny Portage Railroad National Historic Site (ALPO) in Blair and Cambria Counties, Pennsylvania (figure 1). These data establish a base-line for current hydrologic conditions and may be helpful...
Compilation of data not available in the National Water Information System for domestic wells sampled by the U.S. Geological Survey in Bradford County, Pennsylvania, May-August 2016
This dataset contains the lithologic class and topographic position index information and quality-assurance and quality-control data not available in the online National Water Information System for 72 domestic wells sampled by the U.S. Geological Survey in Bradford County, Pennsylvania, May-August 2016. The topographic position index (TPI) for each well location was computed on the...
Filter Total Items: 90
Exploring spatial and temporal symptoms of the freshwater salinization syndrome in a rural to urban watershed
The freshwater salinization syndrome (FSS), a concomitant watershed-scale increase in salinity, alkalinity, and major-cation and trace-metal concentrations, over recent decades, has been described for major rivers draining extensive urban areas, yet few studies have evaluated temporal and spatial FSS variations, or causal factors, at the subwatershed scale in mixed-use landscapes. This...
Authors
Nicole K. Marks, Charles A. Cravotta, Marissa Lee Rossi, Camila Silva, Peleg Kremer, Steven T. Goldsmith
Complex hydrology and variability of nitrogen sources in a karst watershed
Streams draining karst areas with rapid groundwater transit times may respond relatively quickly to nitrogen reduction strategies, but the complex hydrologic network of interconnected sinkholes and springs is challenging for determining the placement and effectiveness of management practices. This study aims to inform nitrogen reduction strategies in a representative agricultural karst...
Authors
John Clune, Charles A. Cravotta, Admin Husic, Hilary J Dozier, Kurt Eric Schmidt
Legacy sediment as a potential source of orthophosphate: Preliminary conceptual and geochemical models for the Susquehanna River, Chesapeake Bay watershed, USA
Nutrient pollution from agriculture and urban areas plus acid mine drainage (AMD) from legacy coal mines are primary causes of water-quality impairment in the Susquehanna River, which is the predominant source of freshwater and nutrients entering the Chesapeake Bay. Recent increases in the delivery of dissolved orthophosphate (PO4) from the river to the bay may be linked to long-term...
Authors
Charles A. Cravotta, Travis L. Tasker, Peter M. Smyntek, Joel Blomquist, John Clune, Qian Zhang, Noah Schmadel, Natalie Katrina Schmer
Determination and prediction of micro scale rare earth element geochemical associations in mine drainage treatment wastes
Acid mine drainage (AMD) has been proposed as a novel source of rare earth elements (REE), a group of elements that includes critical metals for clean energy and modern technologies. REE are sequestered in the Fe–Al–Mn-rich precipitates produced during the treatment of AMD. These AMD solids are typically managed as waste but could be a REE source. Here, results from AMD solids...
Authors
Benjamin C. Hedin, Mengling Y. Stuckman, Charles A. Cravotta, Christina L. Lopano, Rosemary C. Capo
Land development and road salt usage drive long-term changes in major-ion chemistry of streamwater in six exurban and suburban watersheds, southeastern Pennsylvania, 1999-2019
In urbanized areas, the “freshwater salinization syndrome” (FSS), which pertains to long-term increases in concentrations of major ions and metals in fresh surface waters, has been attributed to road salt application. In addition to FSS, the water composition changes as an influx of sodium (Na+) in recharge may displace calcium (Ca2+), magnesium (Mg2+), potassium (K+), and trace metals...
Authors
Marissa Lee Rossi, Peleg Kremer, Charles A. Cravotta, Krista E. Seng, Steven T. Goldsmith
Salinity and total dissolved solids measurements for natural waters: An overview and a new salinity method based on specific conductance and water type
The total concentration of dissolved constituents in water is routinely quantified by measurements of salinity or total dissolved solids (TDS). However, salinity and TDS are operationally defined by their analytical methods and are not equivalent for most waters. Furthermore, multiple methods are available to determine salinity and TDS, and these methods have inherent differences. TDS is...
Authors
R. Blaine McCleskey, Charles A. Cravotta, Matthew P. Miller, Fred D. Tillman, Paul Stackelberg, Katherine J. Knierim, Daniel Wise
Gross alpha-particle activity and high 226Ra concentrations do not correspond with high 210Po in the Atlantic and Gulf Coastal Plain aquifers of the United States
210Po, which is of human-health concern based on lifetime ingestion cancer risk, is indirectly regulated in drinking water through the U.S. Environmental Protection Agency’s gross alpha-particle activity (GAPA) maximum contaminant level of 15 pCi/L (picocuries per liter). This regulation requires independent measurement of 226Ra for samples exceeding the GAPA screening level of 5 pCi/L...
Authors
Zoltan Szabo, Charles A. Cravotta, Paul Stackelberg, Kenneth Belitz
Determination and prediction of rare earth element eeochemical associations in acid mine drainage treatment wastes
Acid mine drainage (AMD) has been proposed by various researchers as a novel source of rare earth elements (REE), a group of elements that include critical metals for clean energy and modern technologies. REE tend to be sequestered in the Fe-Al-Mn-rich solids produced during the treatment of AMD. These solids are typically managed as waste, but could be a low-cost, readily available REE...
Authors
B.C. Hedin, Charles A. Cravotta, M.Y. Stuckman, C.L. Lopano, R.C. Capo, R.S. Hedin
PHREEQ-N-AMDTreat+REYs water-quality modeling tools to evaluate acid mine drainage treatment strategies for recovery of rare-earth elements
The PHREEQ-N-AMDTreat+REYs water-quality modeling tools have the fundamental capability to simulate aqueous chemical reactions and predict the formation of metal-rich solids during the treatment of acid mine drainage (AMD). These new user-friendly, publicly available tools were expanded from the PHREEQ-N-AMDTreat tools to include the precipitation of rare-earth elements plus yttrium...
Authors
Charles A. Cravotta
Long-term impacts of impervious surface cover change and roadway deicing agent application on chloride concentrations in exurban and suburban watersheds
Roadway deicing agents, including rock salt and brine containing NaCl, have had a profound impact on the water quality and aquatic health of rivers and streams in urbanized areas with temperate climates. Yet, few studies evaluate impacts to watersheds characterized by relatively low impervious surface cover (ISC; 15 %). Here, we use long-term (1997-2019), monthly streamwater quality...
Authors
Marissa L. Rossi, Peleg Kremer, Charles A. Cravotta, Krista E. Scheirer, Steven T. Goldsmith
Pollutant co-attenuation via in-stream interactions between mine drainage and municipal wastewater
Municipal wastewater (MWW) and mine drainage (MD) are common co-occurring sources of freshwater pollution in mining regions. The physicochemical interactions that occur after mixing MWW and MD in a waterway may improve downstream water quality of an impaired reach by reducing downstream concentrations of nutrients and metals (i.e., “co-attenuation”). A first-order stream (Bradley Run in...
Authors
Charles J. Spellman, Peter M. Smyntek, Charles A. Cravotta, Travis L. Tasker, William H. J. Strosnider
Mine drainage precipitates attenuate and conceal wastewater-derived phosphate pollution in stream water
Hydrous ferric-oxide (HFO) coatings on streambed sediments may attenuate dissolved phosphate (PO4) concentrations at acidic to neutral pH conditions, limiting phosphorus (P) transport and availability in aquatic ecosystems. Mesh-covered tiles on which “natural” HFO from abandoned mine drainage (AMD) had precipitated were exposed to treated municipal wastewater (MWW) effluent or a mixture...
Authors
Peter M. Smyntek, Natalie Lamagna, Charles A. Cravotta, William H. J. Strosnider
Interactive PHREEQ-N-AMDTreat+REYs water-quality modeling tools to evaluate potential attenuation of rare-earth elements and associated dissolved constituents by aqueous-solid equilibrium processes (software download)
Software utilizing PHREEQC with user interface. The PHREEQ-N-AMDTreat+REYs geochemical modeling tools have the fundamental capability to simulate and predict key reactions related to the treatment of acid mine drainage and the formation of treatment solids, including the adsorption of rare-earth elements plus yttrium (REYs) onto hydrous iron, aluminum, and manganese oxides. These new...
Interactive PHREEQ-N-Titration-PO4-Adsorption water-quality modeling tools to evaluate potential attenuation of phosphate and associated dissolved constituents by aqueous-solid equilibrium processes (software download)
Two complementary executable water-quality modeling tools (CausticTitration_PO4mg.exe, CausticTitration_PO4moles.exe) simulate equilibrium processes that may attenuate dissolved concentrations of phosphate (PO4) plus associated concentrations of iron (Fe), aluminum (Al), manganese (Mn), calcium (Ca), and sulfate (SO4) as pH and other solution characteristics change during titration with...
PHREEQ-N-AMDTreat
USGS developed, in cooperation with the Office of Surface Mining Reclamation and Enforcement, “user-friendly” aqueous geochemical modeling tools to simulate changes in water quality during passive and active treatment of acid mine drainage.
Interactive PHREEQ-N-AMDTreat Water-Quality Modeling Tools to Evaluate Performance and Design of Treatment Systems for Acid Mine Drainage (software download)
The PHREEQ-N-AMDTreat aqueous geochemical modeling tools described herein simulate changes in pH and solute concentrations resulting from passive and active treatment of acidic or alkaline mine drainage (AMD). The “user-friendly” interactive tools, which are publicly available software, utilize PHREEQC equilibrium aqueous and surface speciation models and kinetics models for O2 ingassing...
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government