EPA’s Final Regional Haze Guidance Highlights State Discretion, Flexibility

New guidance issued by the Environmental Protection Agency (EPA) on Aug. 20 to help states prepare for the second implementation period of the federal regional haze program puts emphasis on “discretion and flexibilities” they can use to comply with long-standing mandates to protect visibility in federal areas.  

While it is not binding, the EPA’s new regional haze guidance document replaces a draft guidance issued by the Obama administration in 2016. Its key objective is to provide states with guidance to develop a regional haze state implementation plan (SIP) for the second implementation period (2018–2028) for the 1999-promulgated Regional Haze Rule. 

Revising the program in a January 2017 final rule, the EPA extended deadlines to July 31, 2021, for states to submit SIPs, which are periodic plans that show how they are making progress toward achieving visibility improvement goals. The final rule also revised progress tracking, including the way in which some days of the year should be selected to constitute the “20 percent most impaired days.” That change focused attention on days when anthropogenic emissions impair visibility instead of days when wildfires and natural dust storms more greatly contribute to reduced visibility. 

According to the EPA, the new guidance document formalizes objectives the Trump administration outlined in its September 2018-issued “Regional Haze Reform Roadmap,” a memorandum in which EPA Administrator Andrew Wheeler told industry and states that the agency intends to revisit certain aspects of the January 2017 Regional Haze Rule. 

The rule, he said, should be anchored in the program’s “core statutory foundation and certain key principles,” which include giving states the lead, to reduce state planning burdens, and to leverage emissions reductions achieved through other programs under the Clean Air Act. 

“Data show that state efforts have achieved significant improvements in visibility throughout the country with visual range improving by 20 to 30 miles in national parks and wilderness areas between 2000 and 2015,” said Wheeler on Aug. 20. “We are following our Regional Haze Roadmap to build on lessons learned during the first implementation period and provide enhanced support for states during the second implementation period.”

As the EPA noted, the new guidance document is organized by SIP development step and provides example approaches and recommendations for each of the steps. But it also underscores flexibilities afforded under the rule. 

For example, the guidance document notes that the rule “does not explicitly list factors that a state must or may not consider when selecting the sources for which it will determine what control measures are necessary to make reasonable progress.” It adds: “A state opting to select a set of its sources to analyze must reasonably choose factors and apply them in a reasonable way given the statutory requirement to make reasonable progress towards natural visibility.” 

And while it notes the “primary cause of regional haze is light extinction by particulate matter [PM],” it lists a number of direct and precursor pollutants that can impair visibility—including sulfur dioxide, nitrogen oxides, volatile organic compounds, and ammonia—that states can consider when developing SIPs. The agency offers reference sources, including IMPROVE data and a 2018 technical guidance document on tracking visibility progress, to help states develop light extinction budgets—which are essentially pie charts showing the light extinction contribution from each PM ambient species for single days and average budgets for the 20% most anthropogenically impaired days. 

However, the agency recommends against using “the fact that a a PM species accounts for only a small percentage of total light extinction” by itself, noting, “a large portion of the total light extinction may be due to natural source impacts, even on the 20% most most anthropogenically impaired days.”

The new guidance has garnered the ire of the National Parks Conservation Association (NCPA), a 100-year-old nonpartisan group that advocates for national park conservation. The group said on Aug. 20 that the new guidance helps states and fossil fuel power generators “dodge responsibility” to improve air quality in nations parks and wilderness areas, as required by the Regional Haze Rule. 

The regional haze rule “is a time-tested, effective program that requires federal and state agencies as well as stakeholders to work together to restore clear skies at national parks like Yosemite, Grand Canyon and Great Smoky Mountains, protecting millions of visitors and surrounding communities from air pollution,” it said.

The Obama administration’s 2016 proposed guidance was designed to help states meet their obligations under the rule, it said. “But today’s guidance from the Trump administration is an abrupt, near total departure from the original and creates uncertainty for states, industry and the public as the second round of the Regional Haze planning is already underway.”

Key changes to the new guidance that the group alleges are problematic are that they offer little direction to states because it “provides generalized statements that fail to instruct states on what they must do to create an acceptable Regional Haze implementation plan due in 2021.” 

The guidance also ignores “polluters and modern controls,” the NPCA claims, because it removes the adoption of the Best Available Retrofit Technology (BART) Guidelines, which allows “pollution sources to continue operating without effective clean air controls.” Finally, the guidance “discourages states from developing robust technical information that justify Regional Haze state implementation plans,” it claims. These include computer modeling “showing whether and to what extent emissions are harming national parks and wilderness areas.” 

Sonal Patel is a POWER senior associate editor (@sonalcpatel, @POWERmagazine)