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Sulfur Dioxide (SO2) Pollution

SO2 Nonattainment Area SIP Requirements

SO2 (1971) Area Requirements

SO2 Nonattainment NSR
SO2 SIP - Primary Standard
SO2 SIP - Secondary Standard

SO2 (2010) Area Requirements

SO2 Attainment Demonstration
SO2 Contingency Measures
Emission Inventory
SO2 Nonattainment NSR

See the nonattainment state and national reports for the status of state submissions to meet these requirements, and EPA's actions on the submissions: