The Environmental Protection Agency (EPA) approved the State of Washington's State Implementation Plan (SIP) submissions, ensuring they meet specific infrastructure requirements for air quality standards set in 2010 and 2015, particularly for sulfur dioxide and ozone. Despite some administrative issues and adverse public comments regarding resources and funding, the EPA found Washington's SIP compliant with necessary requirements. The rule, which does not impose additional federal requirements, will be effective on March 22, 2021. The SIP approval mainly applies to non-trust lands within specific Indian reservation areas as outlined by federal law.
Simple Explanation
The EPA told Washington that their plans to keep the air clean from certain bad gases, like sulfur dioxide and ozone, are good enough. This plan doesn't change federal rules and will start working on March 22, 2021.