Exposed Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
Lisa A Senior
Lisa Senior is a hydrologist with the USGS Pennsylvania Water Science Center and has been involved with both groundwater and surface-water investigations since 1986, becoming Project Chief for numerous studies in Pennsylvania since 1988.
Recent Studies
- Baseline surveys of groundwater quality in and near areas of Marcellus Shale gas development
- Evaluations of naturally occurring radionuclides, trace elements, and methane in groundwater
- Effects of land use on groundwater and surface-water quality
- Modeling of surface-water quality
- Characterization of fractured-rock hydrogeology of the Newark Basin to support contaminant delineation, monitoring, and remedial management in southeastern Pennsylvania
Professional Experience
Pennsylvania Water Science Center: 1986 - present
Branch of Regional Geophysics, Menlo Park, California: 1981 - 1983
Education and Certifications
M.S. in Hydrology, University of Arizona, Tucson
B.A. in Geology, Middlebury College, Middlebury, Vermont
Science and Products
Contaminants in groundwater near former Navy bases in southeastern Pennsylvania
Hydrologic and Water Quality Studies of PFAS in Pennsylvania
Contaminants in Groundwater near Superfund sites in Pennsylvania
Regional Synthesis of Groundwater Quality in Domestic Supply Wells in Northeast and North Central Pennsylvania
Chester County, Pennsylvania
Groundwater Quality of Domestic Supply Wells in Pennsylvania
Pre-2013 Bibliography of USGS publications - Chester County, Pennsylvania (Archive)
Evaluation of Radon in Groundwater and Indoor Air in Pennsylvania
Optical measurements for surface water samples collected within the Neshaminy Creek basin during November 2021
Altitude of selected beds and inferred faults in boreholes as identified from geophysical logs at Valmont TCE Site, Luzerne County, Pennsylvania
Data compilation for regional synthesis of chemical characteristics of groundwater used for domestic supply in north-east and north-central Pennsylvania
Water-level data and selected field notes for aquifer-interval-isolation tests at and near the former Naval Air Warfare Center Warminster, Bucks County, Pennsylvania, 2018-19 (ver. 2.0, January 2024)
Compiled data for groundwater levels, groundwater withdrawals by wells and quarries, and point-source discharges to streams in the vicinity of Willow Grove and Warminster, Bucks and Montgomery Counties, Pennsylvania, for selected years during 1999-2017
MODFLOW 6 and MODPATH 7 model data sets used to evaluate groundwater flow in the vicinity of Horsham and Warminster, Bucks and Montgomery Counties, Pennsylvania-Preliminary simulations for conditions in 1999, 2010, 2013, 2016, and 2017
Field properties and results of laboratory analysis of groundwater samples collected from 79 wells in Pike County, Pennsylvania, 1982-2015
Data for regression models developed to estimate fecal coliform concentrations at five stream sites, Chester County, Pennsylvania (2017)
Exposed Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
Boulder of Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
Boulder of Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
Results of 2018–19 water-quality and hydraulic characterization of aquifer intervals using packer tests and preliminary geophysical-log correlations for selected boreholes at and near the former Naval Air Warfare Center Warminster, Bucks County, Pennsylva
Factors Affecting Groundwater Quality Used for Domestic Supply in Marcellus Shale Region of North-Central and North-East Pennsylvania, USA
Geophysical and video logs of selected wells at and near the former Naval Air Warfare Center Warminster, Bucks County, Pennsylvania, 2017-19
Hydrogeologic framework, water levels, and selected contaminant concentrations at Valmont TCE Superfund Site, Luzerne County, Pennsylvania, 2020
The Valmont TCE Superfund Site, Luzerne County, Pennsylvania is underlain by fractured and folded sandstones and shales of the Pottsville and Mauch Chunk Formations, which form a fractured-rock aquifer recharged locally by precipitation. Industrial activities at the former Chromatex Plant resulted in trichloroethene (TCE) contamination of groundwater at and near the facility, which was identified
Groundwater withdrawals and regional flow paths at and near Willow Grove and Warminster, Pennsylvania—Data compilation and preliminary simulations for conditions in 1999, 2010, 2013, 2016, and 2017
Baseline assessment of groundwater quality in Pike County, Pennsylvania, 2015
Estimated fecal coliform bacteria concentrations using near real-time continuous water-quality and streamflow data from five stream sites in Chester County, Pennsylvania, 2007–16
Effects of changes in pumping on regional groundwater-flow paths, 2005 and 2010, and areas contributing recharge to discharging wells, 1990–2010, in the vicinity of North Penn Area 7 Superfund site, Montgomery County, Pennsylvania
Baseline assessment of groundwater quality in Wayne County, Pennsylvania, 2014
A reconnaissance spatial and temporal assessment of methane and inorganic constituents in groundwater in bedrock aquifers, Pike County, Pennsylvania, 2012-13
Investigations of groundwater system and simulation of regional groundwater flow for North Penn Area 7 Superfund site, Montgomery County, Pennsylvania
Groundwater-level trends and forecasts, and salinity trends, in the Azraq, Dead Sea, Hammad, Jordan Side Valleys, Yarmouk, and Zarqa groundwater basins, Jordan
Changes in groundwater levels and salinity in six groundwater basins in Jordan were characterized by using linear trends fit to well-monitoring data collected from 1960 to early 2011. On the basis of data for 117 wells, groundwater levels in the six basins were declining, on average about -1 meter per year (m/yr), in 2010. The highest average rate of decline, -1.9 m/yr, occurred in the Jordan Side
Web Tools
Pennsylvania Real-Time Water Quality
Real-time computed concentrations of water-quality constituents such as suspended sediment and fecal coliform bacteria are calculated using ordinary least squares regression models. The results of these models, along with direct water-quality measurements, can be viewed here as time-series graphs, or downloaded as tabular data.
Science and Products
- Science
Contaminants in groundwater near former Navy bases in southeastern Pennsylvania
USGS has investigated groundwater flow and contaminant transport in the vicinity of former Navy bases in Bucks and Montgomery Counties, southeastern Pennsylvania, in cooperation with the U.S. Navy. Additional cooperative support for these investigations has been provided by the U.S. Environmental Protection Agency, Pennsylvania Department of Environmental Protection, Bucks and Montgomery counties...Hydrologic and Water Quality Studies of PFAS in Pennsylvania
USGS is working with federal, state, and local partners to monitor and evaluate perfluoroalkyl and polyfluoroalkyl substances (PFAS) in Pennsylvania's groundwater and surface waters. A recent study sampled tap water in Pennsylvania (and other states) and detected PFAS chemicals in some samples.Contaminants in Groundwater near Superfund sites in Pennsylvania
USGS has investigated groundwater flow and contaminant transport in the vicinity of Superfund and other hazardous-waste sites in Pennsylvania, in cooperation with EPA. Additional cooperative support has been provided by the U.S. Department of Defense, National Park Service, Pennsylvania Department of Environmental Protection, Philadelphia, Bucks, Chester, and Montgomery Counties, and local...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.Chester County, Pennsylvania
Since 1969, the Pennsylvania Water Science Center has had a cooperative program with Chester County to measure and describe water resources. Cooperation has been primarily with the Chester County Water Resources Authority, with participation from the Chester County Health Department. This partnership provides Chester County with scientific information for water-resources management.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...Pre-2013 Bibliography of USGS publications - Chester County, Pennsylvania (Archive)
This is an Archive. A bibliography of USGS publications for Chester County, Pennsylvania, Pre-2013. Pre-2013 Publications available from the USGS Publications Warehouse are on the "Publications" tab. Other publications listed below are not, or in some cases are only partially available at the Publications Warehouse.Evaluation of Radon in Groundwater and Indoor Air in Pennsylvania
Existing groundwater and indoor air radon-222, hereafter referred to as "radon", concentrations were aggregated and evaluated for 16 geologic units throughout the state of Pennsylvania to provide a better understanding of potential human exposure to radon. - Data
Optical measurements for surface water samples collected within the Neshaminy Creek basin during November 2021
Here we report optical data collected as part of a collaborative study between USGS Pennsylvania Water Science Center, Pennsylvania Department of Environmental Protection and Water Mission Area Proxies Project. The optical measurements reported here were collected to aide in the characterization of water sources and mixtures and establish proxies (surrogates) for per- and poly-fluorinated alkyl suAltitude of selected beds and inferred faults in boreholes as identified from geophysical logs at Valmont TCE Site, Luzerne County, Pennsylvania
This dataset contains altitudes of selected beds and inferred faults in boreholes within an area of interest determined by the U.S. Environmental Protection Agency (EPA) at the Valmont TCE Superfund site in Luzerne County, Pennsylvania. The selected beds correspond to sections of borehole geophysical logs with elevated natural gamma activity as described in the U.S. Geological Survey (USGS) Open-FData 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 reporting, the wWater-level data and selected field notes for aquifer-interval-isolation tests at and near the former Naval Air Warfare Center Warminster, Bucks County, Pennsylvania, 2018-19 (ver. 2.0, January 2024)
The U.S. Geological Survey (USGS) conducted aquifer interval isolation (packer) tests of discrete water-bearing zones using straddle packers in 13 wells in Northampton, Warminster, and Warwick Townships and Ivyland Borough, Bucks County, Pennsylvania during 2018-19 to support detailed groundwater investigations at and near the former Naval Air Warfare Center (NAWC) Warminster, where groundwater coCompiled data for groundwater levels, groundwater withdrawals by wells and quarries, and point-source discharges to streams in the vicinity of Willow Grove and Warminster, Bucks and Montgomery Counties, Pennsylvania, for selected years during 1999-2017
This USGS Data Release includes hydrologic data compiled for selected years during the period 1990-2017 to support the development and calibration of a numerical groundwater model used to simulate groundwater flow paths at and near former and currently active military bases in Montgomery and Bucks Counties in southeastern Pennsylvania (Goode and Senior, 2020). The hydrologic data compiled for theMODFLOW 6 and MODPATH 7 model data sets used to evaluate groundwater flow in the vicinity of Horsham and Warminster, Bucks and Montgomery Counties, Pennsylvania-Preliminary simulations for conditions in 1999, 2010, 2013, 2016, and 2017
In cooperation with the U.S. Navy, USGS developed and calibrated a numerical MODFLOW 6 model to simulate regional groundwater flow under selected conditions during 1999-2017 at and near the former Willow Grove Naval Air Station Joint Reserve Base in Horsham, Montgomery County and the former Naval Air Warfare Center Warminster in Bucks County, Pennsylvania. The model simulations provide informationField properties and results of laboratory analysis of groundwater samples collected from 79 wells in Pike County, Pennsylvania, 1982-2015
Water-quality data for groundwater samples collected by the U.S. Geological Survey from 79 wells in Pike County, Pennsylvania, 1982-2015. Data consist of field properties and results of laboratory analysis for concentrations of inorganic constituents, dissolved gases (methane, ethane and propane), radon-222, gross alpha and beta radioactivity, radium-226, and volatile organic compounds (VOCs) andData for regression models developed to estimate fecal coliform concentrations at five stream sites, Chester County, Pennsylvania (2017)
This data release supports the following publication: Senior, Lisa A., 2017, Estimated Fecal Coliform Bacteria Concentrations Using Near Real-Time Water-Quality and Streamflow Data From Five Stream Sites in Chester County, Pennsylvania, 200716: U.S. Geological Survey Scientific-Investigations Report 20175075 (https://doi.org/10.3133/sir20175075). The U.S. Geological Survey (USGS), in cooperation w - Multimedia
Rock, partings, ferns, hillside, Mt. Zion site, PennsylvaniaRock, partings, ferns, hillside, Mt. Zion site, Pennsylvania
Exposed Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
Exposed Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
Quartzite rock, flowering ground cover, East Mount Zion site, York County, PennsylvaniaQuartzite rock, flowering ground cover, East Mount Zion site, York County, PennsylvaniaBoulder of Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
Boulder of Hellam Conglomerate member of the Chickies Quartzite at East Mount Zion Superfund Site, York County, Pennsylvania. (Lisa Senior, USGS)
- Publications
Filter Total Items: 39
Results of 2018–19 water-quality and hydraulic characterization of aquifer intervals using packer tests and preliminary geophysical-log correlations for selected boreholes at and near the former Naval Air Warfare Center Warminster, Bucks County, Pennsylva
The U.S. Geological Survey (USGS) collected data on the vertical distribution of hydraulic head, specific capacity, and water quality using aquifer-interval-isolation tests and other vertical profiling methods in 15 boreholes completed in fractured sedimentary bedrock in Northampton, Warminster, and Warwick Townships, Bucks County, Pennsylvania during 2018–19. This work was done, in cooperation wiAuthorsLisa A. Senior, Alex R. FioreFactors Affecting Groundwater Quality Used for Domestic Supply in Marcellus Shale Region of North-Central and North-East Pennsylvania, USA
Factors affecting groundwater quality used for domestic supply within the Marcellus Shale footprint in north-central and north-east Pennsylvania are identified using a combination of spatial, statistical, and geochemical modeling. Untreated groundwater, sampled during 2011–2017 from 472 domestic wells within the study area, exhibited wide ranges in pH (4.5–9.3), total dissolved solids (TDS, 22–196AuthorsCharles A. Cravotta, Lisa A. Senior, Matthew D. ConlonGeophysical and video logs of selected wells at and near the former Naval Air Warfare Center Warminster, Bucks County, Pennsylvania, 2017-19
The U.S. Geological Survey (USGS) collected borehole geophysical and video logs in 17 open-hole wells in Northampton, Warminster, and Warwick Townships, Bucks County, Pennsylvania during 2017–19 to support detailed groundwater investigations at and near the former Naval Air Warfare Center (NAWC) Warminster, where groundwater contamination with per- and polyfluoroalkyl substances (PFAS) had becomeAuthorsLisa A. Senior, J. Alton Anderson, Philip H. BirdHydrogeologic framework, water levels, and selected contaminant concentrations at Valmont TCE Superfund Site, Luzerne County, Pennsylvania, 2020
The Valmont TCE Superfund Site, Luzerne County, Pennsylvania is underlain by fractured and folded sandstones and shales of the Pottsville and Mauch Chunk Formations, which form a fractured-rock aquifer recharged locally by precipitation. Industrial activities at the former Chromatex Plant resulted in trichloroethene (TCE) contamination of groundwater at and near the facility, which was identified
AuthorsLisa A. Senior, Alex R. Fiore, Philip H. BirdGroundwater withdrawals and regional flow paths at and near Willow Grove and Warminster, Pennsylvania—Data compilation and preliminary simulations for conditions in 1999, 2010, 2013, 2016, and 2017
In 2014, groundwater samples from residential and public supply wells in the vicinity of two former U.S. Navy bases at Willow Grove and Warminster, and an active Air National Guard Station at Horsham, Bucks and Montgomery Counties, Pennsylvania, were found to have concentrations of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), which are per- and polyfluoroalkyl substances (PFAuthorsDaniel J. Goode, Lisa A. SeniorBaseline assessment of groundwater quality in Pike County, Pennsylvania, 2015
The Devonian-age Marcellus Shale and the Ordovician-age Utica Shale, which have the potential for natural gas development, underlie Pike County and neighboring counties in northeastern Pennsylvania. In 2015, the U.S. Geological Survey, in cooperation with the Pike County Conservation District, conducted a study that expanded on a previous more limited 2012 study to assess baseline shallow groundwaAuthorsLisa A. Senior, Charles A. CravottaEstimated fecal coliform bacteria concentrations using near real-time continuous water-quality and streamflow data from five stream sites in Chester County, Pennsylvania, 2007–16
Several streams used for recreational activities, such as fishing, swimming, and boating, in Chester County, Pennsylvania, are known to have periodic elevated concentrations of fecal coliform bacteria, a type of bacteria used to indicate the potential presence of fecally related pathogens that may pose health risks to humans exposed through water contact. The availability of near real-time continuAuthorsLisa A. SeniorEffects of changes in pumping on regional groundwater-flow paths, 2005 and 2010, and areas contributing recharge to discharging wells, 1990–2010, in the vicinity of North Penn Area 7 Superfund site, Montgomery County, Pennsylvania
A previously developed regional groundwater flow model was used to simulate the effects of changes in pumping rates on groundwater-flow paths and extent of recharge discharging to wells for a contaminated fractured bedrock aquifer in southeastern Pennsylvania. Groundwater in the vicinity of the North Penn Area 7 Superfund site, Montgomery County, Pennsylvania, was found to be contaminated with orgAuthorsLisa A. Senior, Daniel J. GoodeBaseline assessment of groundwater quality in Wayne County, Pennsylvania, 2014
The Devonian-age Marcellus Shale and the Ordovician-age Utica Shale, geologic formations which have potential for natural gas development, underlie Wayne County and neighboring counties in northeastern Pennsylvania. In 2014, the U.S. Geological Survey, in cooperation with the Wayne Conservation District, conducted a study to assess baseline shallow groundwater quality in bedrock aquifers in WayneAuthorsLisa A. Senior, Charles A. Cravotta, III, Ronald A. SlotoA reconnaissance spatial and temporal assessment of methane and inorganic constituents in groundwater in bedrock aquifers, Pike County, Pennsylvania, 2012-13
Pike County in northeastern Pennsylvania is underlain by the Devonian-age Marcellus Shale and other shales, formations that have potential for natural gas development. During 2012–13, the U.S. Geological Survey in cooperation with the Pike County Conservation District conducted a reconnaissance study to assess baseline shallow groundwater quality in bedrock aquifers prior to possible shale-gas devAuthorsLisa A. SeniorInvestigations of groundwater system and simulation of regional groundwater flow for North Penn Area 7 Superfund site, Montgomery County, Pennsylvania
Groundwater in the vicinity of several industrial facilities in Upper Gwynedd Township and vicinity, Montgomery County, in southeast Pennsylvania has been shown to be contaminated with volatile organic compounds (VOCs), the most common of which is the solvent trichloroethylene (TCE). The 2-square-mile area was placed on the National Priorities List as the North Penn Area 7 Superfund site by the U.AuthorsLisa A. Senior, Daniel J. GoodeGroundwater-level trends and forecasts, and salinity trends, in the Azraq, Dead Sea, Hammad, Jordan Side Valleys, Yarmouk, and Zarqa groundwater basins, Jordan
Changes in groundwater levels and salinity in six groundwater basins in Jordan were characterized by using linear trends fit to well-monitoring data collected from 1960 to early 2011. On the basis of data for 117 wells, groundwater levels in the six basins were declining, on average about -1 meter per year (m/yr), in 2010. The highest average rate of decline, -1.9 m/yr, occurred in the Jordan Side
AuthorsDaniel J. Goode, Lisa A. Senior, Ali Subah, Ayman Jaber - Web Tools
Web Tools
Pennsylvania Real-Time Water Quality
Real-time computed concentrations of water-quality constituents such as suspended sediment and fecal coliform bacteria are calculated using ordinary least squares regression models. The results of these models, along with direct water-quality measurements, can be viewed here as time-series graphs, or downloaded as tabular data.
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