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This data set includes sample information and results for third-party performance assessment samples analyzed for hormones and pharmaceuticals during the same general time period as environmental samples collected by the National Water-Quality Assessment (NAWQA) Project for a study of groundwater resources used for drinking-water supply across the United States, 2013 through 2015. Hormone and pharmaceutical results are provided for spiked and unspiked samples submitted by the Quality Systems Branch (QSB) Organic Blind Sample Project (OBSP), providing information regarding analyte recovery and occurrence of false positive and false negative results. Included in this data release are the following data tables: Table...
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This data release presents results of chemical analyses of groundwater sampled during summer and autumn of 2019 and spring of 2020 from 23 wells in the Great Miami buried-valley aquifer (GM-BVA) of southwestern Ohio. Groundwater and quality-control samples were analyzed to determine concentrations of selected per- and polyfluoroalkyl substances (PFAS). Groundwater and related quality-control samples were collected from 22 of 23 wells and analyzed for 24 different PFAS by two different laboratories that used slightly different proprietary isotope-dilution based adaptations of U.S. Environmental Protection Agency (USEPA) method 537.1, referred to as method 1 and method 2. Results from PFAS analysis of groundwater...
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From October 2017 through September 2022, the National Water Quality Network (NWQN) monitored 110 surface-water river and stream sites and more than 1,800 groundwater wells for a large number of water-quality analytes, for which associated quality-control data and corresponding statistical summaries are included in this data release. The quality-control data—for samples that were collected in the field (at all 110 surface-water sites, 350 groundwater wells, and 16 quality-control-only sites), prepared in the laboratory, or prepared by a third party—can be used to assess the quality of environmental data collected by the NWQN through the estimation of bias and variability in reported results. The general analyte...
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This data record contains questions and responses to a USGS-wide survey conducted to identify issues and needs associated with quality assurance and quality control (QA/QC) of USGS timeseries data streams. This research was funded by the USGS Community for Data Integration as part of a project titled “From reactive- to condition-based maintenance: Artificial intelligence for anomaly predictions and operational decision-making”. The poll targeted monitoring network managers and technicians and asked questions about operational data streams and timeseries data collection in order to identity opportunities to streamline data access, expedite the response to data quality issues, improve QA/QC procedures, reduce operations...


    map background search result map search result map Third-party performance assessment data encompassing the time period of analysis of groundwater samples collected for hormones and pharmaceuticals by the National Water-Quality Assessment Project in 2013-15 Per- and polyfluoroalkyl substance concentrations, age estimates, redox categories, and related data for groundwater from the Great Miami buried-valley aquifer, southwestern Ohio, 2019–20 Questions and responses to USGS-wide poll on quality assurance practices for timeseries data, 2021 Field, laboratory, and third-party quality-control data associated with sites and analytes monitored by the USGS National Water Quality Network, October 2017 through September 2022 Per- and polyfluoroalkyl substance concentrations, age estimates, redox categories, and related data for groundwater from the Great Miami buried-valley aquifer, southwestern Ohio, 2019–20 Third-party performance assessment data encompassing the time period of analysis of groundwater samples collected for hormones and pharmaceuticals by the National Water-Quality Assessment Project in 2013-15 Questions and responses to USGS-wide poll on quality assurance practices for timeseries data, 2021 Field, laboratory, and third-party quality-control data associated with sites and analytes monitored by the USGS National Water Quality Network, October 2017 through September 2022