Connecticut Department of 

ENERGY & 

~

~ 

rENVI RONMENTAL 

PROTECTION 

79 Elm Street • Hartford, CT 06106-5127 www.ct.gov/deep Affirmative Action/Equal Opportunity Employer 

August 5, 2015 

David B. Conroy, Chief 

Air Programs Branch 

EPA New England, Region 1 

5 Post Office Square — Suite 100 

Boston, MA 02109-3912 

Re: Supplement to Infrastructure State Implementation Plan (SIP) Revisions 

Dear Mr. Conroy: 

The letter addresses a question, a point of information and a request that Region 1 of the U.S. 

Environmental Protection Agency (EPA) presented to the Connecticut Department of Energy 

and Environmental Protection (DEEP) concerning its air quality regulatory programs as set out 

in several infrastructure SIP revisions. 

Regarding the question, Region 1 asked whether Connecticut requires that the condensable 

portion PM 10 and PM 2.5 be considered for the purposes of major new source review 

permitting applicability determinations and for establishing source-specific emissions limits in 

new source review permits. Region 1 has raised this question because Connecticut's definitions 

of "PM 10" and "PM2.5" in section 22a-174-1 of the Regulations of Connecticut State Agencies 

(RCSA) 1do not include explicit references to condensable portions of PM10 and PM2.5. 

DEEP responds in the affirmative as DEEP does currently require consideration of the 

condensable portion of the pollutants PM10 and PM2.5 to determine applicability for major new 

source review and to establish permit limits. DEEP interprets the definitions of the terms "PM 

10" and "PM 2.5" in RCSA section 22a-174-1 to include the condensable portion of the 

pollutants PM 10 and PM 2.5 even though the word "condensable" is not used in those 

definitions. The pollutants are defined in terms of the how each pollutant is measured in ambient 

From RCSA section 22a-174-1: 

(87) "PM 2.5" means particulate matter with an aerodynamic diameter less than or equal to a 

nominal 2.5 micrometers as measured by a reference method set forth in 40 CFR 50, Appendix L, 

and designated as a reference method in accordance with 40 CFR 53 or by an equivalent method 

approved by the Administrator in accordance with 40 CFR 53. 

(88) "PM 10" means particulate matter with an aerodynamic diameter less than or equal to a 

nominal 10 micrometers as measured by a reference method set forth in 40 CFR 50, Appendix J, 

and designated as a reference method in accordance with 40 CFR 53 or by an equivalent method 

approved by the Administrator in accordance with 40 CFR 53. 
David B. Conroy 

Page 2 

5 August 2015 

monitoring, which, as a technical matter, necessarily includes the condensable portions of PM 10 

and PM 2.5. 

Regarding the point of information, Connecticut does have a state statute, Section 22a-7 of the 

Connecticut General Statutes, which provides the Commissioner with emergency powers similar 

to those provided to the Administrator by Section 303 of the Clean Air Act. 

Regarding EPA Region 1's request, it is for a commitment to make regulatory revisions related. 

to Connecticut's prevention of significant deterioration (PSD) and new source review (NSR) 

permitting requirements. The request is for revision of four provisions that EPA Region 1 has 

identified as potentially producing permitting determinations that are not consistent with 

determinations made under the federal requirements, as modified by EPA in the Phase 2 ozone 

implementation rule (70 Fed. Reg. 71612; November 29, 2005). The provisions include the 

definitions of "maj or stationary source," "maj or modification," and "minor source baseline 

date"2in RCSA section 22a-174-1; and the PSD applicability provision in RCSA section 22a174-3a(k)(1)(A). DEEP understands the reason for EPA Region 1's request and is committing to 

pursue the adoption of appropriate revisions to RCSA sections 22a-174-1 and 22a-174-3a to 

conform to the intent of EPA's PSD and NSR program requirements as modified in 2005 and in 

subsequent revisions so that DEEP's infrastructure SIPs may be approved. As DEEP's NSR 

program does not duplicate the federal requirements precisely, DEEP will consider the 

regulatory drafting options available to achieve the intended result and will keep Region 1 

informed of the chosen approach. 

DEEP commits to seek completion of the necessary regulatory revisions as outlined above. 

DEEP understands that EPA intends to provide for an automatic disapproval if the requested 

PSD program revisions are not submitted within the time period designated by EPA in the notice 

(i. e., one year from the publication of the conditional approval). 

Feel free to get in touch with me or Jaimeson Sinclair (860-424-3408) if you have any questions 

concerning this letter. 

Sincerely yours, 

.✓.~- _ 

Anne R. Gobin, Chief 

Bureau of Air Management 

The minor source baseline date for PM2.5 is September 24, 2014.