UNITED ST':'TES ENVIRONMENTAL"PROTECTION AGENCY

Off,ce of Air Quality Planning and Standards

Research Triangle Par•. Nonh Carolina 27711

23 DEC 1983

MEMORANDUM

Subject: Section 107 Questions and Answers

From: G. T. Helms, Chief.{~ Control Programs Operations Branch (HO-15)

To: Air Branch Chief

Regions I-X

The April 21, 1983 memo from Sheldon Meyers on Section 107 Redesignation

Policy has generally resulted in more consistent redesignation packages. Ho~ever, a number of questions have developed since then and it seems

worthwhile now to share with everyone the rp.sponses that have been developed. These quest~ons have arisen in a number of areas.

1. Is air quality data alone sufficient for a redesignation from

nonattainment to attainment?

Answ~r: No. Valid air quality data showing no NAAQS violations must be

supplemented with a demonstration that the a~proved SIP control strategy which provides for attainment has been implemented. The April 21 memo

describes the requirements in detail. In most cases the submittal will ~nclude the most recent eight quarters of data showing attainment and

evidence of an implemented control strategy that EPA had approved. This

demonstration need not necessarily be quantitative. Rather, it need

simply confirm that the control strategy approved in the SIP to address

the problem has indeed been implemented. Where the most recent four

quarters of data showing attainment are available, a state-of-the-art

modeling analysis must be provided which quantifies that the SIP strategy

is sound and that actual enforceable emission reductions are responsible for the air quality improvements.

2. Are the same requirements discussed in answer number 1 applicable to

secondary TSP redesignations?

Answer: Yes. As for primary standards, some reason has to be shewn for

the improvement in air quality. This can consist of an implemented

control strategy, some other Federa11y enforceable statewide regulations.

or a well-documented explanation that the circumstances which resulted in

the initial designation have changed or were incorrect. The integrity of

the designation process should be preserved, for both primary and secondary pollutants. Further. it should be noted that States are not penalized by

remaining secondary nonattainment. Therefore, a control strategy or

other demonstration needs to be "included with thes~ redesignation requests.

209
2 o.

3. Can a control strategy that has not been approved by EPA as part of

the SIP be used ta support a redesignation?

Answer: In general, no. However, an exception will be made if the

physi ca1 c; rcumstances' and long-term economi c factors are such that the

implemented measures have the same weight as a SIP: for example, the

permanent closing of the major· emitting sources, road paving to eliminate

fugitive emissions, or other irreversible measures. Submittals inclUding such changes, even though not formally approved as SIP reyisions~ have

the practical impact of an EPA approved strategy and can be the basis for

approval of the redesignation.

4. Are the same criteria required to reduce the size of a nonatta;nment

area as are required for redesignating the entire area?

Answer: In general, yes. However~ if a sound cas! can be made that the

State ·overdesignated" initially -- that is, designated a larger area

than EPA required .- then the area can be reduced. The remaining "onattainment area must be compatible with EPA boundary requirements (see April 21,

1983 memo) and.it must oe convincingly demonstrated that the area going

from nonattainment to attainment should not have been designated nonattainment. Other than this specific kind of exception, however, boundary

changes require the same analysis as any nonattainment to attainment

redesignation. When a portion of a nonattainment area is redesignated

attainment, it would help the public if a statement was included in the

notice which explains that a nonattainment portion remains.

5. What criteria are used in redesignating from unclassifiable to attainment

for TSP and S02? - . --- ---_.

Answer: Redesignations from unclassifiable to attainment generally require

the most recent eight consecutive quarters of air quality data demonstrating

attainment. No control strategy demonstration is required since there

would have been no SIP requirement for an unclassifiable area. The S02

redesignations will generally continue to require dispersion modeling• . 6. What is required for reclassifications from unclassifiable to attainment

for ozone, carbon monoxide, and nitrogen oxides?

Answer: Redesignations from unclassifiable to attainment do not involve

any regulatory change. If a State wishes to make such a redes·ignation, it

should be sent forward as a brief explanatory Federal Register notice

documenting the infoMmation. However. the formal table containing the

designation status is not changed since the attainment and unc:lassifiable

designations are combinp.d for these' pollutants.

7. Is there, or has there ~ver been, a SO km policy for ozone nonattainment

areas?

Answer: No. this was only discussed-as an option some years ago but it

never achieved the status of Agency pol~cy.

210
3

These questions and answ!rs highlight some of the significant that have come up since issues

or John Calcagni (FTS 629-5665)

the April 21, 1983 memo. Please call Bill Beal

on Section 107 -issues. if you have further comments or questions

cc: 8. Bauman

O. White

R• Campbell S. Mei burg J. Ulfelder

211