Regional Haze: State Implementation Plans

The Environmental & Energy Law Program is tracking the environmental regulatory rollbacks of the Trump administration. Click here for the list of rules we are followingIf you’re a reporter and would like to speak with an expert on this rule please email us

Shenandoah Valley on hazy and clear days.

Why It Matters

Haze occurs when small particles of air pollution scatter and absorb sunlight, blurring scenic views and decreasing the distance that can be seen from overlooks. In response to this problem, Congress enacted Section 169A of the Clean Air Act to protect visibility in national parks and wilderness areas. The Environmental Protection Agency (EPA) subsequently promulgated the Regional Haze Rule in 1999. The program directs states to implement pollution control plans, called State Implementation Plans (SIPs), to improve visibility and air quality at national parks. If a state fails to submit a satisfactory plan, EPA is expected to promulgate a Federal Implementation Plan (FIP) to replace or supplement the state’s SIP. (See here for our tracker post on the Regional Haze Rule, beyond the state programs.)

Since the implementation of the regional haze program, the average visual range has increased from 90 to 120 miles in some western parks and from 50 to 70 miles in some eastern parks. In addition to the benefits for visitors at national parks, the regional haze program delivers public health benefits. The primary pollutants that cause regional haze, including particulate matter, nitrogen oxides (NOx), sulfur dioxide (SO2), and volatile organic compounds (VOCs), are linked to serious health effects including premature death. Some of these pollutants also contribute to acid rain. Implementation of the Regional Haze Rule and associated regulations has produced sharp declines in the emissions of those pollutants, resulting in improved air quality as well as improved visibility in scenic areas. In fact, EPA estimates that during the first implementation period (2007-2018), there was a reduction in SO2 emissions of 500,000 tons per year and in NOx emissions of 300,000 tons per year.

Current Status of the Regional Haze SIPs

On April 12, 2018, President Trump directed the Administrator of EPA, Scott Pruitt, to review all existing FIPs and to develop options replace those plans with SIPs.

EPA is also involved in ongoing litigation with multiple states and regulated industries regarding the adequacy of the states’ SIPs and the consequent FIPs that EPA promulgated. Through these legal challenges, several states and industry are seeking more lenient technology standards for polluting facilities. In many cases, the litigation and the FIP involve only a portion of the state’s plan, including pollution controls for specific power plants. The five states that recently challenged EPA’s actions on their Regional Haze SIPs are Arizona, Arkansas, Texas, Utah, and Wyoming.

Last year EPA settled with one of the industrial facilities directly affected by Wyoming’s FIP. In addition, EPA recently approved partial SIP revisions for Texas, Arkansas, and Arizona, authorizing control technologies that will likely result in higher emissions from affected facilities than the FIP that was previously in place. EPA is currently reconsidering and seeking to revise Utah’s FIP.

Outside of the state-specific litigation, EPA is also involved in litigation challenging EPA’s 2016 regulations that enhanced requirements for SIPs to ensure states continue to make progress towards the visibility goals.

Click here learn more about the history of this rule and actions that have been taken on it by the Trump Administration.

HLS Student Orgs

Search Our Site

HLS Evironmental Law on Twitter