Revealed: how a little-known pollution rule keeps the air dirty for millions of Americans

Major investigation shows local governments are increasingly exploiting a loophole in the Clean Air Act, leaving more than 21 million Americans with air that's dirtier than they realize What is the exceptional events rule? The loophole letting US regulators wipe air pollution from the record A legal loophole has allowed the US Environmental Protection Agency to strike pollution from clean air tallies in more than 70 counties, enabling local regulators to claim the air was cleaner than it really ...