Greenwire: U.S. EPA critics were dismayed as federal judges this week kept intact a major Obama administration rule to slash mercury emissions from power plants, but others saw a silver lining.
Having the mercury rule in place, they say, bolsters their arguments against another major rule, EPA's Clean Power Plan.
In the litigation over that landmark rule to limit power plants' greenhouse gas emissions, a central argument made by EPA's critics is that the agency lacks authority to issue the climate rule...