April 26, 2018 

Docket ID No. EPA-HQ-OAR-2017-0355 

Re: Proposal to repeal the Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric Utility Generating Units (EGUs), commonly referred to as the Clean Power Plan (CPP), as promulgated on October 23, 2015. 

We, the undersigned, submit the following comments in response to the Federal Register Notice “Proposal to repeal the Carbon Pollution Emission Guidelines for Existing Stationary Sources” (82 FR 48035). In deciding whether or not to repeal the Clean Power Plan (CPP), EPA must take into account the following scientific findings. 

We present findings on the foregone benefits associated with potentially repealing the CPP and the estimated impacts of an alternative power plant carbon standard that is reportedly favored by some groups known as a narrow “inside the fenceline” or “at the source”-only approach that focuses primarily on making heat rate improvements at a source, known as Building Block 1 in the CPP. 

The findings presented here illustrate a flaw in EPA’s proposed legal interpretation of section 111(a) and 111(d), which is the sole basis upon which the proposed repeal rests, by demonstrating that a narrow “at the source”-only approach is estimated to result in only nominal national carbon dioxide (CO2) emission reductions and an increase on sulfur dioxide (SO2) emissions from the power sector compared to the CPP and a business as usual reference case with no power plant carbon standards, and therefore does not represent the “best system of emission reduction” (BSER). 

EPA’s proposed interpretation of section 111 comes down to two assertions – first, that the BSER must be applied only at the source and second, that Building Blocks 2 and 3 of the CPP, which apply to substituting electricity generation from coal-fired power plants with natural gas or renewable energy, cannot be the basis of the emissions standards. Neither of these assertions is supported or supportable. 

The first assertion in and of itself does not advance EPA’s argument. In its proposal to repeal the CPP, EPA recognizes that “operational changes” to a source fall within the scope of the BSER. Nowhere in the proposal, however, does the agency address the fact that, in practice, reducing utilization at a source is an operational change that utilities have used to reduce emissions. In fact, the proposal completely fails to address the ample CPP record, which demonstrates that managing and reducing utilization at individual facilities has long been integral to utilities’ practices for complying with a number of Clean Air Act air pollution control programs. 

The proposal also fails to recognize the actual function of Building Blocks 2 and 3 in establishing the CPP emissions standards. The proposal makes much of the distinction between the application of measures at the source and the action of owners and operators at the source, as if the application of measures, including reduced utilization, is undertaken by an agency other than the source’s operator or operating system. Building Blocks 2 and 3 describe the substitution activity that is used to generate electricity to meet customer demand and represent the CPP’s device for quantifying, in part, what degree of reduced utilization at affected sources is reasonable and appropriate. EPA’s narrow “at the source”-only interpretation, including its exclusion of the considerations on which Building Blocks 2 and 3 are based, is contrived and arbitrary. Based on the results presented here, EPA’s interpretation could actually undermine the regulatory purpose of section 111 by allowing for increased CO2 emissions in some regions due to emissions rebound. 

Any repeal of the CPP must be based on a reasonable, non-arbitrary analysis of the BSER that is unconstrained by the EPA’s proposed narrow “at the source”-only approach and that compares the estimated impacts of this narrow approach to the current CPP. The foundational case law on the interpretation and application of “best system of emission reduction” states that in determining the ‘‘best’’ system, the EPA must also take into account ‘‘the amount of air pollution’’ reduced. Sierra Club v. Costle, 657 F.2d 298, 326 (D.C. Cir. 1981). It is in this context that our presentation of an analysis of the pollution emissions, air quality, health, and ecosystem benefits foregone with the proposed repeal of the CPP and the potential impacts of a narrow “at the source”-only approach applies and must be explicitly considered by the EPA in its attempts to justify the legality of the constrained BSER determination which is the basis of its proposed repeal of the CPP. 

Figure: Premature deaths avoided for a power plant carbon a narrow “inside the fenceline” power plant carbon standard in 2020 compared to a business as usual reference case with no power plant carbon standard. Premature deaths would increase in states shaded in red under a narrow "inside the fenceline" policy. From Driscoll et al. 2015. 

Map shows that premature deaths increase in many states under an inside the fenceline carbon standard