Maryland cities must cut more pollution from trash incinerators

Maryland is tightening rules for how much air pollution can come from trash incinerators. These facilities will now have to use better technology to reduce nitrogen oxide emissions.

For years, states have set their own standards for how much pollution is "reasonably available" to control. This proposal means Maryland is adopting a stricter definition for trash incinerators, which could push other states to follow. It also means the US environmental regulators are approving a specific, measurable step towards cleaner air from these facilities.