REGIONAL HAZE PLANNING IN THE WESTERN AND SOUTHEASTERN UNITED STATES

• Jurisdiction: United States

Air Quality Challenges Facing the Natural Resources Industry in the Western United States
(Nov 2007)
CHAPTER 8B
REGIONAL HAZE PLANNING IN THE WESTERN AND SOUTHEASTERN UNITED STATES
Tom Moore
Western Regional Air Partnership
Fort Collins, Colorado

feature

Regional Haze Planning in the Western and Southeastern United States

by Tom Moore and Patricia Brewer

Reprinted with permission from EM, the Air & Waste Management Association's monthly magazine for environmental managers.

Tom Moore is the technical coordinator for the WRAP regional planning organization. Patricia Brewer is the technical coordinator for the VISTAS regional planning organization. E-mail: mooret@cira.colostate.edu; pat.brewer@ncmail.net.

Florida Everglades

The Regional Haze Rule (RHR), promulgated in July 1999, contains the U.S. Environmental Protection Agency's (EPA) most far-reaching requirements for states to study air quality and reduce emissions.¹ Each state must complete comprehensive technical analyses for haze-causing pollutants, while also conducting long-term planning to improve visibility conditions in the nation's 156 visibility-protected federal Class I areas.

This article discusses state responsibilities under the RHR, illustrates regional differences in approaches to meet those responsibilities, and suggests priorities for assessment and implementation of haze emissions control strategies. The regional haze planning described here is supported by the Regional Planning Organizations (RPOs) in the western (the Western Regional Air Partnership, WRAP; www.wrapair.org) and southeastern (the Visibility Improvement State and Tribal Association of the Southeast, VISTAS; www.vistas-sesarm.org) United States.

STATE RESPONSIBILITIES

The statutory national visibility goal in the 1977 U.S. Clean Air Act Amendments (CAAA) of "remedying existing and preventing future impairment" is defined in the RHR as a requirement for states to improve visibility on the haziest days and prevent any degradation of the clearest days at each Class I area (see sidebar "State Responsibilities Under the Regional Haze Rule").

For the Class I areas in each state, that state is required to determine the nature and causes of visibility impairment, evaluate sources and emissions control options, and set reasonable progress goals for 2018.² The 2018 goals must be based on consultation with all contributing states (and the responsible federal land managers), although the state with the Class I area can only directly address control of emissions under its own jurisdiction. The state must demonstrate progress for the haziest days and protection of the clearest days in 2018 as an initial forecast of the long-term progress toward estimated "natural conditions" in 2064. If the natural conditions target is not likely to be met based on the rate of progress predicted by 2018, an alternative estimate of the date to attain natural conditions is required, as well as the reasons for the revised target date.

Each state that either contains a Class I area or contributes to haze at a Class I area in another state is required to submit a regional haze State Implementation Plan (SIP) to EPA by December 17, 2007. States are then required to implement emissions controls and air quality management strategies that are determined to be reasonable. Approval of the SIP by EPA may take several months to years. The RHR requires an alternating cycle of mid-course SIP review and revision every five years (first review in 2012) and full SIP demonstrations every 10 years (next due in 2018) until natural conditions are

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achieved in approximately 60 years. The 2012 SIP review will need to address several elements to assess ongoing progress toward visibility goals (see sidebar "Elements to be Addressed in 2012 Regional Haze SIP Revision"). Unlike the National Ambient Air Quality Standards (NAAQS), where EPA is responsible for periodic reviews, states are responsible for the continuous review cycle under the RHR.

In parallel to the RHR, states are also preparing SIPs during 2007 and 2008 for the existing nonattainment areas for the NAAQS for ozone and particulate matter with a diameter of less than 2.5 microns (PM_2.5). Large regions of the country currently do not attain these health standards. Multipollutant control strategies that address ozone and PM_2.5 will also improve visibility in many Class I areas.

State Responsibilities Under the Regional Haze Rule

Establish 2000-2004 baseline and estimate 2064 natural visibility conditions and the glidepath for a uniform rate of progress to achieve natural conditions.

Establish reasonable progress goals to improve visibility by 2018.

Develop long-term strategies to control emissions that contribute to haze.

Improve visibility on the 20% haziest days and protect visibility [no degradation] on the 20% clearest days.

Submit first SIP by December 17, 2007.

Evaluate progress every five years [next review in 2012]; demonstrate progress in SIP every 10 years [next in 2018].

VISIBILITY CONDITIONS IN THE WEST AND SOUTHEAST

Approximately 75% (116) of the 156 Class I areas are located in the WRAP region and 18 are located in the VISTAS region (see Figure 1). A range of conditions, from near natural conditions to highly impaired visibility, occur between these two regions. As illustrated in Figure 2, the 20% haziest days in the southeastern United States are dominated by ammonium sulfate, predominantly from sulfur dioxide (SO₂) emissions from electric utility and industrial sources, with significant contributions from organic carbon, predominantly from biogenic emissions and wood burning (anthropogenic and natural fires). Most of the 18 Class I areas in the southeastern United States, including the Great Smoky Mountains (Tennessee), Everglades National Park (Florida), and Cape Romain Wildlife Refuge (South Carolina) are located near urban areas; several are influenced by nearby ozone or PM_2.5 nonattainment areas. Small contributions from international emissions are observed at all sites. For example, Saharan dust can dominate PM_2.5 in episodes at the Florida Everglades, but generally not on the 20% haziest days at this site.

Figure 1. Map of Class I areas in United States.

Figure 2. Contributions of particle components to visibility [measured as light...