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Clean Air Status and Trends Network (CASTNET)

CASTNET is a national monitoring network established to assess trends in pollutant concentrations, atmospheric deposition, and ecological effects due to changes in air pollutant emissions.

Clean Air Status and Trends Network (CASTNET)

Monitoring Information

Download Data

Maps & Charts

Publications

What's New

CASTNET site locations, including latitude, longitude, and elevation values, have been updated to reflect site data collected as part of the independent audit program. For more information about the audit program click here: Audit Reports. For the updated site locations download the data file here: Sites.