Sydney Marie Welch
Sydney Welch is a Physical Scientist in the New England Water Science Center.
Professional Experience
Physical Scientist, U.S. Geological Survey, New England Water Science Center, 2021 to Present
Education and Certifications
B.S. Environmental Science and Policy, Plymouth State University, 2020
Science and Products
Advancing subsurface investigations beyond the borehole with passive seismic horizontal-to-vertical spectral ratio and electromagnetic geophysical methods at transportation infrastructure sites in New Hampshire
The U.S. Geological Survey (USGS), in cooperation with the New Hampshire Department of Transportation (NHDOT), surveyed transportation infrastructure sites using rapidly deployable geophysical methods to assess benefits added to a comprehensive site characterization with traditional geotechnical techniques. Horizontal-to-vertical spectral-ratio (HVSR) passive-seismic and electromagnetic...
Authors
James R. Degnan, Krystle Pelham, Neil C. Terry, Sydney M. Welch, Carole D. Johnson
Per- and polyfluoroalkyl substances (PFAS) in New Hampshire soils and biosolids
The U.S. Geological Survey, in cooperation with the New Hampshire Department of Environmental Services, is undertaking a study on per- and polyfluoroalkyl substances (PFAS) in soils and biosolids. The study will characterize PFAS concentrations in shallow soil and selected biosolids throughout the State of New Hampshire, conduct laboratory experiments to improve understanding of how...
Authors
Andrea K. Tokranov, Kate Emma A. Schlosser, Jeffrey M. Marts, Anthony F. Drouin, Leah M. Santangelo, Sydney M. Welch
Water Quality Vertical Profile Data to Support Embayment Monitoring in Long Island Sound, Saugatuck and Sasco-Southport Embayments, Connecticut, 2022-2024
This data release includes vertical water-quality profile data collected from April 2022 to April 2024 at three locations in the Saugatuck River Embayment near Saugatuck, Connecticut, and two locations in the Mill River and one at the mouth of Sasco Brook near Southport Harbor, Connecticut, for the Sasco-Southport Embayment that discharge to Long Island Sound. These data were collected...
Compilation of surficial geology datasets for southern New England
The U.S. Geological Survey, in cooperation with the Federal Highway Administration (FHWA) and the Connecticut, Massachusetts, and Rhode Island Departments of Transportation (DOTs), gathered geospatial data to facilitate the development of a regional Stochastic Empirical Loading and Dilution Model (SELDM) application (Granato and others, 2023). As part of this study, the surficial geology...
Water level, water temperature, and specific conductance data collected during natural gradient tests in observation wells set in the upper transmissive zone of the Ogallala Aquifer, North East 2nd Street Superfund Site, Happy, Texas, 2023
Water level, water temperature, and specific conductance data were collected during natural gradient tests on six observation wells screened in the upper transmissive zone of the Ogallala aquifer at the North East 2nd Street Superfund site in Happy, Texas, from November 6-13, 2023. Tests involved gravity draining 100-160 gallons of a low-concentration salt-spiked solution with an...
Pilot Study of Per- and Polyfluoroalkyl Substances (PFAS) Infiltration to Shallow Groundwater Through Selected Soils in New Hampshire, 2023
In a study conducted by the U.S. Geological Survey (USGS) and the New Hampshire Department of Environmental Services, detectable concentrations of per- and polyfluoroalkyl substances (PFAS) were found in the soil at every site despite targeting locations with no known PFAS sources (Santangelo and others, 2022). The widespread distribution of PFAS concentrations in New Hampshire has since...
Estimation of hydraulic properties in the Ogallala aquifer near Happy, Texas from slug test results at the North East 2nd Street Superfund site, U.S. Geological Survey data release
The North East 2nd Street Superfund site in Happy, Texas, overlies a groundwater plume of primarily carbon tetrachloride (CT) that is contained within an upper transmissive zone (EA Engineering, Science, and Technology, Inc., 2019) of the Ogallala aquifer. The Ogallala aquifer is contained at the site in Tertiary-age sediments of the Ogallala Formation, which are described by Nordstrom...
Confirmatory Sampling for Per- and Polyfluoroalkyl Substances (PFAS) in Shallow Soils Across New Hampshire, 2022
Data for per- and polyfluoroalkyl substances (PFAS) and related chemical and physical characteristics are presented from 30 soil sampling locations within the State of New Hampshire. A total of 15 sites were chosen based on the results of sampling efforts published in Santangelo and others(2022). Sites with relatively high concentrations of PFAS observed during the first study were...
Field-scale investigation of per- and polyfluoroalkyl substances (PFAS) leaching from shallow soils to groundwater at two sites in New Hampshire, 2021-2022
Per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data are presented from shallow soil and groundwater at two sites in New Hampshire. The two sites, the former Brentwood Fire Training Area and White Farm, were selected because materials known to contain PFAS were used at each site. White Farm is an active farm where biosolids have been applied for several years...
Passive Seismic Horizontal-to-Vertical Spectral Ratio Measurements at Transportation Infrastructure Sites in New Hampshire, 2022
In 2022, the U.S. Geological Survey (USGS) in cooperation with the New Hampshire Department of Transportation (NHDOT) made 107 horizontal-to-vertical spectral ratio (HVSR) passive seismic geophysical measurements at four transportation infrastructure sites in New Hampshire to determine the benefits of HVSR as an enhancement to traditional geotechnical site characterizations performed by...
Statewide survey of shallow soil concentrations of per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data across New Hampshire, 2021
Per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data are presented from 100 shallow soil sampling locations within the State of New Hampshire. Sites were randomly determined through an equal-area grid approach (Scott, 1990) targeting undisturbed areas, which included lands classified by the 2016 National Land Cover Database (Dewitz, 2019) as forested...
Science and Products
Advancing subsurface investigations beyond the borehole with passive seismic horizontal-to-vertical spectral ratio and electromagnetic geophysical methods at transportation infrastructure sites in New Hampshire
The U.S. Geological Survey (USGS), in cooperation with the New Hampshire Department of Transportation (NHDOT), surveyed transportation infrastructure sites using rapidly deployable geophysical methods to assess benefits added to a comprehensive site characterization with traditional geotechnical techniques. Horizontal-to-vertical spectral-ratio (HVSR) passive-seismic and electromagnetic...
Authors
James R. Degnan, Krystle Pelham, Neil C. Terry, Sydney M. Welch, Carole D. Johnson
Per- and polyfluoroalkyl substances (PFAS) in New Hampshire soils and biosolids
The U.S. Geological Survey, in cooperation with the New Hampshire Department of Environmental Services, is undertaking a study on per- and polyfluoroalkyl substances (PFAS) in soils and biosolids. The study will characterize PFAS concentrations in shallow soil and selected biosolids throughout the State of New Hampshire, conduct laboratory experiments to improve understanding of how...
Authors
Andrea K. Tokranov, Kate Emma A. Schlosser, Jeffrey M. Marts, Anthony F. Drouin, Leah M. Santangelo, Sydney M. Welch
Water Quality Vertical Profile Data to Support Embayment Monitoring in Long Island Sound, Saugatuck and Sasco-Southport Embayments, Connecticut, 2022-2024
This data release includes vertical water-quality profile data collected from April 2022 to April 2024 at three locations in the Saugatuck River Embayment near Saugatuck, Connecticut, and two locations in the Mill River and one at the mouth of Sasco Brook near Southport Harbor, Connecticut, for the Sasco-Southport Embayment that discharge to Long Island Sound. These data were collected...
Compilation of surficial geology datasets for southern New England
The U.S. Geological Survey, in cooperation with the Federal Highway Administration (FHWA) and the Connecticut, Massachusetts, and Rhode Island Departments of Transportation (DOTs), gathered geospatial data to facilitate the development of a regional Stochastic Empirical Loading and Dilution Model (SELDM) application (Granato and others, 2023). As part of this study, the surficial geology...
Water level, water temperature, and specific conductance data collected during natural gradient tests in observation wells set in the upper transmissive zone of the Ogallala Aquifer, North East 2nd Street Superfund Site, Happy, Texas, 2023
Water level, water temperature, and specific conductance data were collected during natural gradient tests on six observation wells screened in the upper transmissive zone of the Ogallala aquifer at the North East 2nd Street Superfund site in Happy, Texas, from November 6-13, 2023. Tests involved gravity draining 100-160 gallons of a low-concentration salt-spiked solution with an...
Pilot Study of Per- and Polyfluoroalkyl Substances (PFAS) Infiltration to Shallow Groundwater Through Selected Soils in New Hampshire, 2023
In a study conducted by the U.S. Geological Survey (USGS) and the New Hampshire Department of Environmental Services, detectable concentrations of per- and polyfluoroalkyl substances (PFAS) were found in the soil at every site despite targeting locations with no known PFAS sources (Santangelo and others, 2022). The widespread distribution of PFAS concentrations in New Hampshire has since...
Estimation of hydraulic properties in the Ogallala aquifer near Happy, Texas from slug test results at the North East 2nd Street Superfund site, U.S. Geological Survey data release
The North East 2nd Street Superfund site in Happy, Texas, overlies a groundwater plume of primarily carbon tetrachloride (CT) that is contained within an upper transmissive zone (EA Engineering, Science, and Technology, Inc., 2019) of the Ogallala aquifer. The Ogallala aquifer is contained at the site in Tertiary-age sediments of the Ogallala Formation, which are described by Nordstrom...
Confirmatory Sampling for Per- and Polyfluoroalkyl Substances (PFAS) in Shallow Soils Across New Hampshire, 2022
Data for per- and polyfluoroalkyl substances (PFAS) and related chemical and physical characteristics are presented from 30 soil sampling locations within the State of New Hampshire. A total of 15 sites were chosen based on the results of sampling efforts published in Santangelo and others(2022). Sites with relatively high concentrations of PFAS observed during the first study were...
Field-scale investigation of per- and polyfluoroalkyl substances (PFAS) leaching from shallow soils to groundwater at two sites in New Hampshire, 2021-2022
Per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data are presented from shallow soil and groundwater at two sites in New Hampshire. The two sites, the former Brentwood Fire Training Area and White Farm, were selected because materials known to contain PFAS were used at each site. White Farm is an active farm where biosolids have been applied for several years...
Passive Seismic Horizontal-to-Vertical Spectral Ratio Measurements at Transportation Infrastructure Sites in New Hampshire, 2022
In 2022, the U.S. Geological Survey (USGS) in cooperation with the New Hampshire Department of Transportation (NHDOT) made 107 horizontal-to-vertical spectral ratio (HVSR) passive seismic geophysical measurements at four transportation infrastructure sites in New Hampshire to determine the benefits of HVSR as an enhancement to traditional geotechnical site characterizations performed by...
Statewide survey of shallow soil concentrations of per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data across New Hampshire, 2021
Per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data are presented from 100 shallow soil sampling locations within the State of New Hampshire. Sites were randomly determined through an equal-area grid approach (Scott, 1990) targeting undisturbed areas, which included lands classified by the 2016 National Land Cover Database (Dewitz, 2019) as forested...