In the Smith / Voinovich / Brownback analysis , when we analyzed SO2 and NOx reduction levels similar to S. 556 , mercury reduction levels more modest than S. 556 and no CO2 reductions , we did not find significant impacts on coal production or electricity prices .
In the Smith / Voinovich / Brownback analysis , when analyzing SO2 and NOx reduction levels , mercury levels were more modest than S 556 and no CO2 reductions .