Page:Michigan v. EPA.pdf/9

Rh propriate and necessary” requires at least some attention to cost. One would not say that it is even rational, nevermind “appropriate,” to impose billions of dollars in economic costs in return for a few dollars in health or environmental benefits. In addition, “cost” includes more than the expense of complying with regulations; any disadvantage could be termed a cost. EPA’s interpretation precludes the Agency from considering any type of cost—including, for instance, harms that regulation might do to human health or the environment. The Government concedes that if the Agency were to find that emissions from power plants do damage to human health, but that the technologies needed to eliminate these emissions do even more damage to human health, it would still deem regulation appropriate. See Tr. of Oral Arg. 70. No regulation is “appropriate” if it does significantly more harm than good.

There are undoubtedly settings in which the phrase “appropriate and necessary” does not encompass cost. But this is not one of them. Section 7412(n)(1)(A) directs EPA to determine whether “regulation is appropriate and necessary.” (Emphasis added.) Agencies have long treated cost as a centrally relevant factor when deciding whether to regulate. Consideration of cost reflects the understanding that reasonable regulation ordinarily requires paying attention to the advantages and the disadvantages of agency decisions. It also reflects the reality that “too much wasteful expenditure devoted to one problem may well mean considerably fewer resources available to deal effectively with other (perhaps more serious) problems.” Entergy Corp. v. Riverkeeper, Inc., 556 U. S. 208, 233 (2009) (, J., concurring in part and dissenting in part). Against the backdrop of this established administrative practice, it is unreasonable to read an instruction to an administrative agency to determine whether “regulation is appropriate and necessary” as an invitation to