shocker great news epa shoot overreach regulations justice scalia get one right write appropriate impose billions dollars economic cost little benefit return.the supreme court rule federal regulators attempt limit power plant emissions mercury hazardous air pollutants.the rule begin take effect april court say 5-4 vote monday environmental protection agency fail take cost account agency first decide regulate toxic emissions coal- oil-fired plants.the challenge bring industry group 21 republican-led states.writing court justice antonin scalia say appropriate impose billions dollars economic cost return dollars health environmental benefits.the case go back low court epa decide account cost break supreme court rule epa power plant regulations