Tammy Zimmerman (Former Employee)
Science and Products
Freshwater Flow into Chesapeake Bay
Explore resources here describing estimates of freshwater flow entering Chesapeake Bay. The health of the Chesapeake Bay is greatly affected by freshwater flow from rivers draining its watershed. The amount of freshwater flow (also called streamflow) will: • Change salinity levels in the Bay, which affect oysters, crabs, and finfish. • Influence the amounts of nutrients, sediment, and contaminants...
Predictive Modeling of Bacteria Concentrations at Presque Isle State Park, Erie, Pennsylvania
Approximately 7 miles of Lake Erie shoreline lies within Presque Isle State Park in Erie, Pa. Monitored public bathing beaches at Presque Isle make up less than 1 mile. Concentrations of Escherichia coli (E. coli) at monitored beaches in Presque Isle State Park occasionally exceed the single-sample bathing-water standard of 235 colonies per 100 milliliters resulting in potentially unsafe swimming...
Bacteriological quality of groundwater used for household supply
In fractured bedrock aquifers used for domestic supply conditions can exist where contaminants such as bacteria are not filtered out by the soil. Once in the fracture system, little additional filtration takes place. The results of a synotic sampling of domestic wells in the Lower Susquehanna River basin, Pennsylvania and Maryland, showed that bacteria concentrations were higher in areas with high...
Filter Total Items: 19
Evaluating changes in matrix based, recovery-adjusted concentrations in paired data for pesticides in groundwater Evaluating changes in matrix based, recovery-adjusted concentrations in paired data for pesticides in groundwater
Pesticide concentration data for waters from selected carbonate-rock aquifers in agricultural areas of Pennsylvania were collected in 1993–2009 for occurrence and distribution assessments. A set of 30 wells was visited once in 1993–1995 and again in 2008–2009 to assess concentration changes. The data include censored matched pairs (nondetections of a compound in one or both samples of a...
Authors
Tammy M. Zimmerman, Kevin J. Breen
Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002 Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002
Chemical and microbiological analyses of water from 230 wells and 35 springs in the Valley and Ridge Physiographic Province, sampled between 1993 and 2002, indicated that bedrock type (carbonate or siliciclastic rock) and land use were dominant factors influencing groundwater quality across a region extending from northwestern Georgia to New Jersey. The analyses included naturally...
Authors
Gregory C. Johnson, Tammy M. Zimmerman, Bruce D. Lindsey, Eliza L. Gross
Pesticides in ground water in selected agricultural land-use areas and hydrogeologic settings in Pennsylvania, 2003-07 Pesticides in ground water in selected agricultural land-use areas and hydrogeologic settings in Pennsylvania, 2003-07
This report was prepared by the U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Agriculture (PDA) as part of the Pennsylvania Pesticides and Ground Water Strategy (PPGWS). Monitoring data and extensive quality-assurance data on the occurrence of pesticides in ground water during 2003–07 are presented and evaluated; decreases in the land area used for...
Authors
Connie A. Loper, Kevin J. Breen, Tammy M. Zimmerman, John W. Clune
Modeling to Predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania Modeling to Predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania
The Lake Erie beaches in Pennsylvania are a valuable recreational resource for Erie County. Concentrations of Escherichia coli (E. coli) at monitored beaches in Presque Isle State Park in Erie, Pa., occasionally exceed the single-sample bathing-water standard of 235 colonies per 100 milliliters resulting in potentially unsafe swimming conditions and prompting beach managers to post...
Authors
Tammy M. Zimmerman
Factors affecting occurrence and distribution of selected contaminants in ground water from selected areas in the Piedmont Aquifer System, Eastern United States, 1993-2003 Factors affecting occurrence and distribution of selected contaminants in ground water from selected areas in the Piedmont Aquifer System, Eastern United States, 1993-2003
Results of ground-water sampling from 255 wells and 19 springs in 11 studies done by the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program within the Piedmont Aquifer System (PAS) were analyzed to determine the factors affecting occurrence and distribution of selected contaminants. The contaminants, which were selected on the basis of potential human-health effects...
Authors
Bruce D. Lindsey, W. Fred Falls, Matthew J. Ferrari, Tammy M. Zimmerman, Douglas A. Harned, Eric M. Sadorf, Melinda J. Chapman
Monitoring and modeling to predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania Monitoring and modeling to predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania
The Lake Erie shoreline in Pennsylvania spans nearly 40 miles and is a valuable recreational resource for Erie County. Nearly 7 miles of the Lake Erie shoreline lies within Presque Isle State Park in Erie, Pa. Concentrations of Escherichia coli (E. coli) bacteria at permitted Presque Isle beaches occasionally exceed the single-sample bathing-water standard, resulting in unsafe swimming...
Authors
Tammy M. Zimmerman
Science and Products
Freshwater Flow into Chesapeake Bay
Explore resources here describing estimates of freshwater flow entering Chesapeake Bay. The health of the Chesapeake Bay is greatly affected by freshwater flow from rivers draining its watershed. The amount of freshwater flow (also called streamflow) will: • Change salinity levels in the Bay, which affect oysters, crabs, and finfish. • Influence the amounts of nutrients, sediment, and contaminants...
Predictive Modeling of Bacteria Concentrations at Presque Isle State Park, Erie, Pennsylvania
Approximately 7 miles of Lake Erie shoreline lies within Presque Isle State Park in Erie, Pa. Monitored public bathing beaches at Presque Isle make up less than 1 mile. Concentrations of Escherichia coli (E. coli) at monitored beaches in Presque Isle State Park occasionally exceed the single-sample bathing-water standard of 235 colonies per 100 milliliters resulting in potentially unsafe swimming...
Bacteriological quality of groundwater used for household supply
In fractured bedrock aquifers used for domestic supply conditions can exist where contaminants such as bacteria are not filtered out by the soil. Once in the fracture system, little additional filtration takes place. The results of a synotic sampling of domestic wells in the Lower Susquehanna River basin, Pennsylvania and Maryland, showed that bacteria concentrations were higher in areas with high...
Filter Total Items: 19
Evaluating changes in matrix based, recovery-adjusted concentrations in paired data for pesticides in groundwater Evaluating changes in matrix based, recovery-adjusted concentrations in paired data for pesticides in groundwater
Pesticide concentration data for waters from selected carbonate-rock aquifers in agricultural areas of Pennsylvania were collected in 1993–2009 for occurrence and distribution assessments. A set of 30 wells was visited once in 1993–1995 and again in 2008–2009 to assess concentration changes. The data include censored matched pairs (nondetections of a compound in one or both samples of a...
Authors
Tammy M. Zimmerman, Kevin J. Breen
Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002 Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002
Chemical and microbiological analyses of water from 230 wells and 35 springs in the Valley and Ridge Physiographic Province, sampled between 1993 and 2002, indicated that bedrock type (carbonate or siliciclastic rock) and land use were dominant factors influencing groundwater quality across a region extending from northwestern Georgia to New Jersey. The analyses included naturally...
Authors
Gregory C. Johnson, Tammy M. Zimmerman, Bruce D. Lindsey, Eliza L. Gross
Pesticides in ground water in selected agricultural land-use areas and hydrogeologic settings in Pennsylvania, 2003-07 Pesticides in ground water in selected agricultural land-use areas and hydrogeologic settings in Pennsylvania, 2003-07
This report was prepared by the U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Agriculture (PDA) as part of the Pennsylvania Pesticides and Ground Water Strategy (PPGWS). Monitoring data and extensive quality-assurance data on the occurrence of pesticides in ground water during 2003–07 are presented and evaluated; decreases in the land area used for...
Authors
Connie A. Loper, Kevin J. Breen, Tammy M. Zimmerman, John W. Clune
Modeling to Predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania Modeling to Predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania
The Lake Erie beaches in Pennsylvania are a valuable recreational resource for Erie County. Concentrations of Escherichia coli (E. coli) at monitored beaches in Presque Isle State Park in Erie, Pa., occasionally exceed the single-sample bathing-water standard of 235 colonies per 100 milliliters resulting in potentially unsafe swimming conditions and prompting beach managers to post...
Authors
Tammy M. Zimmerman
Factors affecting occurrence and distribution of selected contaminants in ground water from selected areas in the Piedmont Aquifer System, Eastern United States, 1993-2003 Factors affecting occurrence and distribution of selected contaminants in ground water from selected areas in the Piedmont Aquifer System, Eastern United States, 1993-2003
Results of ground-water sampling from 255 wells and 19 springs in 11 studies done by the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program within the Piedmont Aquifer System (PAS) were analyzed to determine the factors affecting occurrence and distribution of selected contaminants. The contaminants, which were selected on the basis of potential human-health effects...
Authors
Bruce D. Lindsey, W. Fred Falls, Matthew J. Ferrari, Tammy M. Zimmerman, Douglas A. Harned, Eric M. Sadorf, Melinda J. Chapman
Monitoring and modeling to predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania Monitoring and modeling to predict Escherichia coli at Presque Isle Beach 2, City of Erie, Erie County, Pennsylvania
The Lake Erie shoreline in Pennsylvania spans nearly 40 miles and is a valuable recreational resource for Erie County. Nearly 7 miles of the Lake Erie shoreline lies within Presque Isle State Park in Erie, Pa. Concentrations of Escherichia coli (E. coli) bacteria at permitted Presque Isle beaches occasionally exceed the single-sample bathing-water standard, resulting in unsafe swimming...
Authors
Tammy M. Zimmerman