UNITEDST':'TES ENVIRONMENTAL"PROTECTION AGENCY Off,ceofAirQualityPlanningandStandards ResearchTrianglePar•.NonhCarolina27711 

### 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 TheApril 21, 1983 memo fromSheldonMeyers on Section 107 Redesignation Policy has generally resulted in more consistentredesignation packages.**Ho~ever,** a number ofquestions 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 anumber 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 forattainment has been implemented. TheApril 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 confirmthat 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 providedwhich 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 awell-documented explanation that the circumstances which resulted in the initial designation have changed orwere 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"includedwith**thes~** redesignation requests.



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### 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 physica1 c;rcumstances' and long-term economic factors are such that the implemented measures have the same weight as aSIP: 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 asound 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 compatiblewith 

### 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. Otherthan this specific kind of exception, however, boundary changes require the same analysis as any nonattainment to attainment redesignation. When aportion of a nonattainment area is redesignated attainment, it would help the public if astatementwas included in the notice which explains that anonattainment 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 fromunclassifiable to attainment for ozone, carbon monoxide, and nitrogen oxides? Answer: Redesignations fromunclassifiable to attainment do not involve any regulatory change. If aStatewishes 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 kmpolicy 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.**



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### These questions and answ!rs highlight some ofthe significant issues that have come up since theApril 21, 1983 memo. Please call Bill Beal orJohnCalcagni (FTS 629-5665) 

### ifyou have further comments orquestions on Section 107

### -issues.

cc: 8. 

### Bauman 

### O. White R•

### Campbell S. 

### Meiburg J. Ulfelder



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