Air Quality Guidelines prepared on the premise that transportation planning and air quality planning are interdependent and that neither should proceed without full consideration of the other were issued in final form by the FHWA in 1974. The Guidelines instruct highway officials responsible for urban transportation planning in areas subject to the 3C process[N 1] to confer with the appropriate air pollution control agencies; annually solicit comments on the consistency of transportation plans with approved State Implementation Plans for attainment and maintenance of air quality; and determine consistency of transportation plans with State Implementation Plans. Other provisions in the Guidelines are intended to ensure adequate coverage of air quality considerations in EIS’s.
Achieving applicable air quality standards in some urban areas will undoubtedly be very difficult. For the more troublesome air quality problem areas, the Environmental Protection Agency (EPA) has required transportation control plans designed to reduce the volume of pollutants by such methods as improving the flow of traffic, improvements in mass transportation, bans on parking, and encouraging carpooling.
Of the various responses to the many environmental problems, only a few set forth specific rules for application to individual projects. Section 4(f) of the Department of Transportation Act is one such instance. Given the availability of a “feasible and prudent alternative,” land from public parks or certain related uses cannot be used for a Federal-aid highway project.
The Noise Standards issued by the FHWA are also based upon a project approach. When predicted noise levels for a project exceed specified design noise levels for various land uses and activities, then noise control measures are to be undertaken. If strict adherence to the Standards are demonstratively unreasonable, there are provisions for flexibility or exceptions.
Like noise, air quality is subject to quantitative analysis, and it might, therefore, be assumed that it would be equally susceptible to a project approach. Because so little is known about the subject of air quality conditions and the elements involved are so varied, project rules have not been established with the same degree of specificity as the Noise Standards. The Air Quailty Guidelines are, therefore, aimed at processes and procedures to assure consistency between highway plans and State air quality plans.
An aerial view of the serpentine sound barrier.
- ↑ Section 134 of title 23, U.S.C.
