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. See the CASTNET Overview Fact Sheet (pdf) and the CASTNET Ozone Monitoring page for more information.
What's New
- Weekly filterpack concentration data (1990-2024) are now available in AQS. A list of CASTNET parameter codes can be found in the lookup table: CASTNET AQS Parameter Codes (xlsx)
- The Bureau of Land Management (BLM) issued a stop work order (SWO) on the WARMS contract in April 2025. The SWO terminated support for data collection at five CASTNET sites across WY: Basin (BAS601), Buffalo (BUF603), Fortification Creek (FOR605), Newcastle (NEC602), and Sheridan (SHE604).
- EPA developed a three-year plan to modernize the Clean Air Status and Trends Network. The CASTNET Modernization Plan is now available.
- CASTNET established a new site at Haskell Indian Nations University (HAS012) in November 2024.