Connecticut Department of



### ENERGY & ENVIRONMENTAL PROTECTION

August 19, 2011

David Conroy, Chief, Air Programs Branch US EPA- New England 5 Post Office Square- Suite 100 (Mail Code OFP05-2) Boston, MA 02109-3912

Re: Addendum to the CAA §110(a)(2)(D)(i)(I) Portion of Connecticut’s Infrastructure Submittal for the 2006 PMzs NAAQS

Dear Mr. Conroy:

On September 18, 2009, the Connecticut Department of Environmental Protection (now the Connecticut Department of Energy and Environmental Protection) submitted a determination that Connecticut’s State Implementation Plan (SIP) adequately addressed the requirements of §§110(a)(1) and (2) of the Clean Air Act (CAA) for the 2006 fine particulate matter (PM2.s) national ambient air quality standards (NAAQS), demonstrating that Connecticut’s resources and authorities are adequate to implement, maintain, and enforce the NAAQS. Considering EPA’s recent release of the Cross-State Air Pollution Rule (CSAPR), Connecticut is submitting this addendum to our September 2009 submittal to clarify how Connecticut complies with §110(a)(2)(D)(i)(I) requirements, as described below.

The §110(a)(2)(D)(i)(I) portion of the September 2009 submittal addresses the requirement that Connecticut prohibit any source or other type of emissions activity in the state from contributing significantly to nonattainment, or interfering with maintenance, of the NAAQS in another state. This portion of Connecticut’s September 2009 submittal indirectly referenced EPA’s 2005 Clean Air Interstate Rule (CAIR) and the associated State program. However, a December 2008 court decision vacated CAIR, but kept CAIR requirements in place temporarilywhile directing EPA to issue a replacement rule. On August 2, 2010, EPA proposed the courtrequired replacement rule, which EPA called the Transport Rule. 1 EPA’s modeling analysis conducted for the proposed Transport Rule supported EPA’s conclusion at the time that Connecticut significantly contributed to nonattainment or interfered with maintenance of the 1996 24-hour PM2.s NAAO, S. After discussions with EPA Region 1 staff regarding the impact of the 2008 court decision upon the approvability of our September 2009 infrastructure submittal and the conclusions in the proposed Transport Rule, on January 7, 2011, Connecticut withdrew the §110(a)(2)(D)(i)(I) portion of the infrastructure submittal, as requested by EPA.

~ See, Federal Implementation Plans To Reduce Interstate Transport of Fine particulate Matter and Ozone (75 FR 45210. 79 Elm Street  ̄ Hartford, CT 06106-5127 www.ct.gov/deep Affirmative Actlon/Equal Opportunity EmployerMr. David Conroy

Page 2 August 19, 2011

On July 6, 2011, EPA finalized CSAPR, which replaces CAIR. The results of EPA’s analysis conducted for CSAPR differ from the results of the proposed Transport Rule.2 CSAPR requirements do not apply to Connecticut because the final rule’s updated air quality modeling led EPA to conclude that Connecticut does not contribute significantly to nonattainment, or interfere with maintenance, of the 2006 PM2.s NAAQS in another state. 3 Therefore, based on EPA’s modeling analysis and conclusions, we are resubmitting the section of our September 18, 2009 infrastructure submittal that addresses interstate transport provisions of §110(a)(2)(D)(i)(I), certifying that Connecticut does not contribute significantly to nonattainment, or interfere with maintenance, of the 2006 PM2.s NAAQS in any other state.

Thank you for your consideration of this clarification of the Connecticut’s infrastructure certification for the 2006 PM2.s NAAQS. If you have any questions or comments concerning this matter, please contact me.

Sincerely,

Anne Gobin Chief, Bureau of Air Management

2 EPA updated its modeling platforms and modeling inputs in response to public comments received on the proposed Transpo~’t Rule and subsequent NODAs and performed other standard updates. 3 EPA’s modeling also concludes that Connecticut does not significantly contribute significantly to nonattainment or maintenance issues in other states for the 1997 ozone and PM2.5 NAAQS. lnfo~rnatinn about EPA’s modeling for CSAPR is available on theh" CSAPR website on the technical information and support documents page: http://www,epa.gov/crossstaterule/techinfo.html.