EPA Memo Sends Message to States on Regional Haze Plans

September 16, 2021

Over the summer, several states were among the first to submit to the U.S. Environmental Protection Agency their regional haze state implementation plan (SIPs) revisions intended to govern the program for the second planning period, which extends through 2028. Some states opted to evaluate a broad range of sources for new emission controls, while others determined that no additional controls are needed, often based on emission reduction progress already achieved through existing regulatory programs and facility shutdowns. Many states are continuing to evaluate what type of approach to take.

EPA guidance issued in 2017 indicated that states might have broad authority to take these different paths, but a new memo issued just weeks before the official deadline for states to submit their new regional haze SIPs to EPA suggests the Biden administration may take a hard look at SIPs that do not impose new control requirements.

The EPA memo, titled “Clarifications Regarding Regional Haze State Implementation Plans for the Second Implementation Period,” seeks to secure meaningful reductions in visibility-impairing pollutants, and explains that the agency expects states to undertake “rigorous” reasonable progress analyses — based on evaluation of four factors states must consider pursuant to the Clean Air Act — to identify opportunities to advance the national visibility goal of unimpaired conditions in protected national parks and wilderness areas. Although the memo expressly says it is not a prejudgment of any state’s SIP, it does suggest that states seeking to avoid imposing new control requirements will need to provide strong support for such decisions.

The memo provides clarifications regarding four broad topics: (1) selection of sources for analysis, (2) characterization of factors for emission control measures, (3) decisions on what control measures are necessary to make reasonable progress and (4) additional issues related to assessing control measures. A few key issues from the memo that states and potentially affected sources should consider are described below.

Regarding source selection, the memo emphasizes that states cannot achieve reasonable progress if they have not identified the right sources. EPA goes on to explain that states must choose sources with the potential to meaningfully reduce each state’s individual contributions to visibility impairment, even if other states contribute much more on a relative basis. Therefore:

  • Each state must participate.
  • If a state relies on a visibility threshold, it must use a meaningful portion of the state’s total contribution to visibility impairment.
  • States should do more than capture a small percentage of their contribution.
  • States with larger sources that contribute more to visibility impairment should select more sources.
  • States with relatively small sources should nonetheless select their largest in-state sources.
  • States must consider sources recommended by other states and by the federal land managers, like the National Park Service.

For sources that are selected for a reasonable progress analysis, the memo makes it clear that states should consider requiring efficiency improvements for existing controls, including limits recently achieved even if they are more stringent than current regulatory requirements. The memo goes on to say that EPA believes that, in “many cases,” a reasonable progress analysis will identify new controls that are appropriate. The memo also reaffirms EPA’s position that only after a state identifies all reasonable control requirements can it then model reasonable progress goals, expressed in terms of visibility improvements, for protected areas. EPA’s statement in this regard suggests some states may be proceeding by selecting goals for protection first, and then opting only for those controls needed to reach those targets.

Among the other issues addressed in the memo is the role of visibility impacts themselves. The memo retains EPA’s previous position that, even though visibility is not one of the four factors states must consider when evaluating reasonable progress, states may nevertheless take visibility impacts into account. The memo adds, however, that small visibility impacts should not be used “to summarily dismiss cost-effective controls.” States instead may use visibility to select among competing cost-effective controls and to select sources and/or prioritize impact. Further, the memo explains that a state that “rejects most (or all) … cost-effective controls … based on visibility benefits is likely to be improperly using visibility.” It also says visibility-impact thresholds used during the first planning period (2007-2018) are likely too high and should not be used for the second planning period.

Finally, the memo provides guidance on consideration of environmental justice issues for the second planning period, a topic EPA has not addressed in detail before with respect to regional haze. The memo’s guidance remains limited, but it makes it clear that states have considerable discretion to make regulatory decisions based on environmental justice considerations. In particular, the memo notes that states can consider environmental justice when reaching out to communities during the SIP development process and to ensure adequate opportunity for feedback on states’ proposed strategies. Perhaps most significantly, however, the memo explains that states can use environmental justice considerations to inform which sources to evaluate for controls and when determining the type and stringency of control requirements.

Although EPA’s most recent memo on implementation of the regional haze program does not expressly overrule or rescind preexisting guidance or regulations, the memo can be viewed as interpreting the Clean Air Act and the regional haze rules to limit certain flexibilities some states may be attempting to use, many of which appeared to be supported by past EPA statements. If a narrower interpretation of state authority prevails, EPA may move to disapprove many regional haze SIPs and impose more burdensome requirements through federal implementation plans.

While states continue to prepare their SIPs, potentially affected companies should work to make sure SIPs are fully supported with strong justifications based on the law. Once EPA begins to act on approving or disapproving SIPs, those same companies will need to engage in the rulemaking process to ensure fair implementation of the program and to preserve their legal arguments if EPA goes too far.