I fail to see how the two enforcement decisions have any relation. Would you like to see the Baltimore Police Department banned from making arrests simply because they have a history of racism? Because that would be the end result of your argument. 

I should point out that every EPA rule has to prove, as in its the burden of the government, that it has a net beneficial economic impact. Indeed, the overall net result of EPA regulation has been a huge creation of jobs and reduction in long-term health harms. I trust this EPA lawsuit meets a similar burden, and if not, it will be thrown out by the court. Either way, this is up for the judicial branch to decide and the legislature interfering without legislation is unconstitutional.