Last week, the EPA issued a proposed finding that greenhouse gases endanger public health and welfare because they contribute to global warming. These findings will surely be challenged in court, but they will just as surely be upheld, given the considerable (and appropriate) deference that courts give to agencies for scientific determinations of this kind. The upshot is that the EPA will be moving forward to regulate carbon dioxide and a number of other greenhouse gases under the Clean Air Act. Indeed, the EPA hardly has a choice in this regard, after the Supreme Court ruled in Massachusetts v. EPA that the agency does indeed have the power to regulate greenhouse gases under the CAA. I think there were a lot of problems with that opinion, but it’s on the books, and so the question is what the next step is for greenhouse gas regulation.
Almost anything would be better than the EPA trying to shoehorn CO2 regulation into the existing framework of the Clean Air Act. The CAA was drafted to deal with more conventional air pollutants like nitrogen dioxide; it is simply not equipped to regulate the basic by-product of our entire, modern, industrialized economy. At the outset, the CAA requires EPA to set a National Ambient Air Quality Standard (NAAQS) for each pollutant–standards which state and local pollution control agencies would then have to meet for their area by whatever means they see fit. This system has worked reasonably well for some conventional pollutants, and it certainly has the virtue of giving local governments meaningful control over pollution policy. But setting a NAAQS for carbon dioxide would be entirely pointless, because the concentration of greenhouse gases (unlike many conventional pollutants) is not determined by local factors, so local governments would have absolutely no control over their concentration. Los Angeles could reduce its own carbon footprint to zero, and it wouldn’t make a lick of difference to its local greenhouse gas concentration as long as China and India keep building power plants.
And of course, EPA has the power to directly regulate both “stationary sources” and automobiles under the Clean Air Act. The threshold for regulation of a stationary source under the Act is currently 250 tons of pollutant per year, which for conventional pollutants usually applies to very large sources like power plants. But there are an incredible number of stationary sources, including things like apartment buildings, that emit more than 250 tons of CO2 per year. Is EPA really going to start regulating all of them?
And consider the enormous predicate decision that EPA would need to reach before embarking on such an adventure: what is our desired level of greenhouse gas emissions? That decision has undeniably enormous economic implications and is simply not one that can be reached with a narrow, objective analysis of scientific data. This is not like figuring out how much mercury is acceptable in drinking water. Capping greenhouse gas emissions will have an tremendous impact on the world’s economic activity for decades. If that is a decision that must be made, Congress is the body that has to do it. A nominally politically accountable government agency acting as the Soup Nazi of greenhouse gases is not a future that any of us should welcome, whether you accept the global warming science or not.