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
Regional Synthesis of Groundwater Quality in Domestic Supply Wells in Northeast and North Central Pennsylvania
Groundwater Quality of Domestic Supply Wells in Pennsylvania
Recoding of AMDTreat Phase 2: Integration of PHREEQ-N-AMDTreat water-quality prediction tools with recoded AMDTreat cost-analysis software
Mine Drainage and Water Quality Research
Coal mine drainage effluents and associated solids major, trace, rare earth element and radium concentrations collected from Pennsylvania, USA
Salinity and total dissolved solid determinations using PHREEQCI
Data compilation for regional synthesis of chemical characteristics of groundwater used for domestic supply in north-east and north-central Pennsylvania
Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018
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
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
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
Complex hydrology and variability of nitrogen sources in a karst watershed
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 increases in
Determination and prediction of micro scale rare earth element geochemical associations in mine drainage treatment wastes
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
Salinity and total dissolved solids measurements for natural waters: An overview and a new salinity method based on specific conductance and water type
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. There is n
Determination and prediction of rare earth element eeochemical associations in acid mine drainage treatment wastes
PHREEQ-N-AMDTreat+REYs water-quality modeling tools to evaluate acid mine drainage treatment strategies for recovery of rare-earth elements
Long-term impacts of impervious surface cover change and roadway deicing agent application on chloride concentrations in exurban and suburban watersheds
Pollutant co-attenuation via in-stream interactions between mine drainage and municipal wastewater
Mine drainage precipitates attenuate and conceal wastewater-derived phosphate pollution in stream water
Factors Affecting Groundwater Quality Used for Domestic Supply in Marcellus Shale Region of North-Central and North-East Pennsylvania, USA
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)
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)
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)
Science and Products
Phosphorus in the Susquehanna River may be tied to legacy sediment and changing pH
Regional Synthesis of Groundwater Quality in Domestic Supply Wells in Northeast and North Central Pennsylvania
Groundwater Quality of Domestic Supply Wells in Pennsylvania
Recoding of AMDTreat Phase 2: Integration of PHREEQ-N-AMDTreat water-quality prediction tools with recoded AMDTreat cost-analysis software
Mine Drainage and Water Quality Research
Coal mine drainage effluents and associated solids major, trace, rare earth element and radium concentrations collected from Pennsylvania, USA
Salinity and total dissolved solid determinations using PHREEQCI
Data compilation for regional synthesis of chemical characteristics of groundwater used for domestic supply in north-east and north-central Pennsylvania
Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018
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
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
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
Complex hydrology and variability of nitrogen sources in a karst watershed
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 increases in
Determination and prediction of micro scale rare earth element geochemical associations in mine drainage treatment wastes
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
Salinity and total dissolved solids measurements for natural waters: An overview and a new salinity method based on specific conductance and water type
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. There is n
Determination and prediction of rare earth element eeochemical associations in acid mine drainage treatment wastes
PHREEQ-N-AMDTreat+REYs water-quality modeling tools to evaluate acid mine drainage treatment strategies for recovery of rare-earth elements
Long-term impacts of impervious surface cover change and roadway deicing agent application on chloride concentrations in exurban and suburban watersheds
Pollutant co-attenuation via in-stream interactions between mine drainage and municipal wastewater
Mine drainage precipitates attenuate and conceal wastewater-derived phosphate pollution in stream water
Factors Affecting Groundwater Quality Used for Domestic Supply in Marcellus Shale Region of North-Central and North-East Pennsylvania, USA
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)
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)
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)
*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