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Clean Air Status and Trends Network (CASTNET) Weekly Ambient Concentrations

Published by U.S. Environmental Protection Agency | U.S. Environmental Protection Agency | Catalog Last Checked: August 03, 2026 at 12:45 AM | Dataset Last Updated: February 11, 2021
Weekly average air concentrations from CASTNET filter pack data in standard Tuesday 9:00 AM - Tuesday 8:00 AM weeks. The data are collected using an open face, 3-stage filter pack. Data include aerosol concentrations of sulfate, nitrate, ammonium, calcium, sodium, potassium, magnesium and chloride and gaseous concentrations of sulfur dioxide and nitric acid. The QAPP and associated SOPs can be found on the CASTNET website: www.epa.gov/castnet/documents-reports. Site location information is included with this dataset. Citation information for this dataset can be found in the EDG's Metadata Reference Information section and Data.gov's References section.

Resources

2 resources available

  • https://gaftp.epa.gov/Castnet/CASTNET_Outgoing/data/drychem.zip

    FILE
  • https://gaftp.epa.gov/Castnet/CASTNET_Outgoing/data/site.zip

    FILE

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