A few examples of what such area class identifying tables might look like appear in Section 3 of the report to the Congress and are reproduced here as Tables I and II. Not included in the report to the Congress were some still more complex area class discriminators I had included in my manuscript such as the combination of a population density weighting factor (Table III) with air quality ratio to produce a weighted air quality ratio as a composite discriminator (Table IV) that a community could use to determine its emission standard class.

There are cogent arguments for both variable and uniform national emission standards. The arguments for variable standards are the same ones that led to the deletion of national emission standards from the 1967 amendments to the Clean Air Act. Many of you remember that provisions to enact national emission standards were included in the amendments proposed by the Johnson Administration in 1966. These provisions elicited much debate at that time. The principal argument that led to their deletion by the Congress, after the public hearings on the proposed amendments, was that it was improper to apply the same limits to a plant in the open spaces of Wyoming as to a like plant in New York City, i.e. that air in Wyoming is clean and can be dirtied, whereas the air in New York is dirty and should be cleaned. Concepts such as those of Tables I and IV provide a means for accommodating national emission standards to areas as diverse as Wyoming and New York City by reclassifying such areas with respect to emission standard classes at regular time intervals, e.g., every ten years, as shown in Figure 4.

Ratio:1

TABLE I.-Emission standard classes based on existing air quality

2.5 and over

1.0 to 2.49

0.5 to 0.99

0.1 to 0.49

0.0999 and under

1 Existing air quality divided by air quality standard.

TABLE II.-VARIATION OF EMISSION STANDARD CLASSES WITH ATMOSPHERIC AREAS

Emission standard

class

ABCDE

Note: Assignment of emission standard classes is continued for the other six areas: Washington coastal, CaliforniaOregon coastal, Rocky Mountain, Great Plains, Great Lakes, and mid-Atlantic coastal.

TABLE III.-Population density weighing factor

Population weighting

Poulation per 1,000 square miles:

10 million and over..

1 million to 9.999 million__.

100,000 to 999,999.

10,000 to 99,999 –

1000 to 9999.

100 to 999 – – –

99 and under__.

factor

TABLE IV.-Emission standard class based on weighted air quality ratio

7654321

It should be noted that the approaches embodied in both Tables I and IV require the use of an air quality standard in arriving at emission standard class. Therefore, before any such selection procedure could be incorporated into federal legislation or regulation, there would have to be parallel or prior enactment of procedures to either establish national air quality standards, or State and local air quality standards, covering all areas in the United States, conforming to federal review for consistency with federal criteria.

Non-Degredation

It should be apparent that the nation cannot, at the same time, adopt the approach shown in Figure 4 and a non-degradation policy with respect to the air over all parts of the nation. There are those who have interpreted the statement in Section 101 (b) (1) of the Clean Air Act, as amended, that national policy shall be to "protect and enhance the quality of the nation's air resources" as a