### Penn~ylvani':. 

## Department of**Environ~ental Pro~ection**  Rachel Carson State Office Building

Secretary

Mr. Shawn M. Garvin Regional Administrator P.O. Box 2063 Harrisburg, P A 17105-2063 May 24, 2011

U.S. Environmental Protection Agency, Region III 1650 Arch Street (Mail Code: 3RAOO) Philadelphia, PA 19103-2029

Dear Mr. Garvin: 717-787-2814

On April 26, 2010, the Department ofEnvironmental Protection (DEP) submittedthe Commonwealth ofPennsylvania's "infrastructure" state implementationplan (SIP) revision to the U.S. Environmental Protection Agency (EPA) to address the requirements ofsection 110(a)(2) ofthe Cleau Air Act (CAA) for the 2006 24-hour National AmbientAir Quality Standard for fine particulate matter (PM2S)' The purpose ofthis letter is to clarifythe infrastructure SIP revision submittal relatedto the elements ofsection 110(a)(2)(D)(i)(II) and section 11O(a)(2)(D)(ii) ofthe CAA.

Section 110(a)(2)(D)(i)(II) ofthe CAArequires that a state's SIP have adequate provisions to prohibit any source or emissions activity from emitting airpollutauts in amounts that would interfere with measures in other states to prevent significautdeterioration ofair quality orvisibility. The Commonwealth ofPennsylvauia's approved SIP meets the infrastructure element for prevention ofsignificant deterioration (PSD) requirements for the. 24-hour PM2.S staudard. The federal PSD provisions are adopted aud incorporated by reference in their entirety in Pennsylvania's PSD regulations codified at 25 

### Pa. Code § 127.83 (relating to adoption ofprogram). These provisions were approved by EPA on August 21, 1984, and subsequently codified in the SIP at 40 CFR 

### § 52.2058 (relating to prevention ofsignificant air quality deterioration). 49 FR 33128.

In regard to the visibility element for the infrastructure SIP revision, on December 20,2010, DEP submitted a Regional Haze SIP revision to EPA pursuant to sections 169A aud 169B ofthe CAA aud 40 CFR Part 51 Subpart P (relating to protection ofvisibility). The December 2010 Regional Haze SIP submittal also serves the purpose ofmeeting Pennsylvauia's relevaut and applicable requirements nnder section 110(a)(2) ofthe CAA, including section 110(a)(2)(D)(i)(II). This approach is consistent withthe guidauce provided in the EPA memoraudnm from William T. Harnett, Director, Air Quality Policy Division, Office of Air Quality Planning aud Staudards, entitled "Guidauce on SIP Elements Under Sections 110(a)(I) aud (2) for the 2006 24-Hour Fine Particle (PM2S) National Ambient Air Quality Staudards (NAAQS)," dated September25,2009.

An Equal Opportunity Employer www.dep.state.pa.us Printed on Recycled Paper 

# @Mr. Shawn M. Garvin 

### 2 May 24, 2011

Section 110(a)(2)(D)(ii) requires that states ensure compliance withthe applicable requirements ofsections 126 and 115 (relating to interstate and international pollution abatement). DEP has demonstrated that the Commonwealth has met its obligations pursuantto section 126 ofthe CAA and 

### itcurrently has no pending obligations pursuant to CAA section 126(b). Any subsequent findings issued by EPA under section 126 would be addressed in the SIP codified at 40 CFRPart 52, SubpartNN (relating to Pennsylvania). DEP has made the necessary submittals to demonstrate that Pennsylvaniahas adequate provisions insuring future compliance with the requirements ofsections 126 and 115 ofthe CAA, as may be necessary.
Should you have any questions or need additional information regarding this clarification ofthe Commonwealth's infrastructure SIP revision for the 24-hour PM2

.S standard, please contact Joyce E. Epps, Director, BureauofAir Quality, bye-mail atjeepps@state.pa.us or by telephone at 717-787-9702.



### 'V"'v''''''' 1. Krancer Secretary