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Publication Number:      Date:  Sept/Oct 2000
Issue No: Vol. 64 No. 2
Date: Sept/Oct 2000


Atlanta 'Conforms' to Clean Air Requirements

by James M. Shrouds


The Atlanta region has experienced extraordinary increases in population and development over the last two decades. Between 1980 and 1999, the population of the Atlanta region grew by 64 percent with 1.3 million new residents. This growth resulted in severe congestion of the region's transportation system and contributed to Atlanta's serious air quality problems.

Citizens and business groups became concerned about the threat to Atlanta's quality of life, and matters came to a head in January 1998 when Atlanta was unable to demonstrate that its transportation plan conformed to Clean Air Act (CAA) requirements. This triggered a conformity lapse that lasted for more than two years, severely limiting Atlanta's ability to use federal transportation funds for both transit and highways.

In the last year, however, Atlanta made a major turnabout in its transportation and air quality planning. Under the leadership of Gov. Roy E. Barnes and with the cooperation of many area agencies and leaders, Atlanta developed a new transportation plan and program, which are significantly different from the previous ones. By committing the state to addressing air quality, environmental justice, and transportation planning issues, the governor placed the Atlanta region on a path to resolve its long-term transportation problems.

Under CAA, metropolitan planning organizations, such as the Atlanta Regional Commission (ARC), must show that their long-range transportation plans and their transportation improvement programs (TIPs) meet, or "conform," to state air quality implementation plans (SIPs). CAA requires each state to prepare a SIP that shows procedures for monitoring, attaining, maintaining, and enforcing compliance with federal air quality standards. The SIP includes a "budget" that sets a limit on the amount of emissions that can come from all motor vehicles. To conform, the transportation plan and the TIP must result in lower emissions than this budget.


Legal battles over Atlanta's transportation-air quality plans may have only enjoyed a short truce. A local chapter of one of the country's more active environmental advocacy groups has announced plans to challenge the recent conformity determination of the metropolitan areas's transportation plan. At the heart of the expected litigation is the Sierra Club's contention that federal officials exceeded their authority in granting the Atlanta area more time to attain the standard for ozone when transportation plans were not shown to be in conformity.

Atlanta was designated a serious nonattainment area for ozone which carries a Clean Air Act-mandated deadline of 1999 for reaching the standard. New state plans for air quality and new budgets for ozone precursor pollutants reflect an extension of the 1999 requirement for attainment.

Targeting the transportation plan developed by the Atlanta Regional Commission (ARC), the Sierra Club is charging that the emissions budget used to assess the plan's air quality impact is both outdated and inaccurate. In addition, club officials argue that the new air quality plans for Atlanta do not demonstrate attainment of the one-hour ozone standard.

While the plaintiff in the looming lawsuit appears to be straightforward, the targets of the action are not as clear. One Sierra Club official noted that FHWA would be a likely candidate because of the agency's role in providing conformity determinations. In addition, because the overall intent of the litigation seems to be to delay implementation of the transportation plan, both the Atlanta and state transportation agencies may be drawn into the battle as well as state and local regulatory agencies.

The Sierra Club may not hold the flag alone for very long. The national organization Environmental Defense and groups in the metropolitan area and from around the state are weighing their options toward joining in. Should they decide to move forward, Sierra Club officials plan on filing a notice of intent to sue by early September.

--Michael Koontz

The long-range transportation plan, the TIP, and the SIP must be updated periodically. If an updated transportation plan or the TIP fails to conform to the SIP, most new highway and transit projects cannot proceed. This is called a conformity lapse. In January 1998, ARC was unable to develop an updated, conforming transportation plan, and the Atlanta area entered a conformity lapse.

Developing a 20-year transportation plan that meets mobility needs and air quality goals is a major challenge. To help meet this challenge, the Georgia General Assembly in 1999 created, at the urging of Gov. Barnes, the Georgia Regional Transportation Authority (GRTA). GRTA is charged with combating air pollution, traffic congestion, and poorly planned development in the metropolitan Atlanta area to ensure that the area sustains its economic growth and maintains its quality of life. GRTA has the authority to issue bonds, assist local governments in financing mass transit or other projects to alleviate air pollution, approve the TIP in the region, and approve major developments such as large subdivisions or commercial buildings.


Atlanta is one of several metropolitan areas that has banned the purchase of new diesel vehicles. Other large cities adopting this policy include Los Angeles and Sacramento. While an estimated 93 percent of the nation's buses still run on diesel fuel, about one in five new vehicles purchased in 1998 ran on natural gas, according to INFORM, A nonprofit environmental research group. INFORM also reports that between 1998 and 2000, the number of city systems fielding at least a few natural gas vehicles rose from 57 to 65. Up through 1999, more than 3,000 natural gas-powered buses were in use with U.S. fleets. --Michael Koontz

ARC developed a new transportation plan, placing more emphasis on transit, bicycle/pedestrian facilities, air quality improvements, and highway system preservation. Equally important in the shift in investment were provisions that ARC adopted to make significant changes in land use, increase density, and facilitate greater use of transit.

As ARC developed this new transportation plan, the Georgia Environmental Protection Division also revised the SIP to demonstrate attainment of air quality standards. Georgia's revised projected emissions budget was declared "adequate" by the U.S. Environmental Protection Agency (EPA).

However, several environmental groups challenged the adequacy finding of this revised budget, and the budget was stayed by the Federal Court of Appeals for the 11th Circuit. Because the court stayed EPA's adequacy finding of this projected budget, the budget contained in the last SIP approved by the EPA came back into effect. This budget actually sets a lower emissions limitation for the critical nitrogen oxide pollutant than the budget placed on hold by the court.

Using this budget, on July 25, 2000, the Federal Highway Administration (FHWA) and the Federal Transit Administration (FTA) completed a technically rigorous determination that the Atlanta area's transportation plan and TIP conform to its currently approved SIP. The decision follows federal rules and has the support of EPA, which plays a key role because it administers the CAA.

With the approval of the conformity determination, the Atlanta region can now move forward to implement its long-range transportation plan. City and state officials should be commended for setting a new direction that will enhance air quality, reduce the impetus for further urban sprawl, and benefit communities in the Atlanta area that have long been excluded from obtaining needed transportation services. FHWA and the FTA will continue to work closely with their partners in Georgia to ensure the necessary access and mobility for everyone in the Atlanta metropolitan area and to improve air quality for generations to come.

James M. Shrouds is the director of the Office of Natural Environment in the Federal Highway Administration.



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