1 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION III 1650 Arch Street Philadelphia, Pennsylvania 19103

DATE: February

22, 2011 SUBJECT: Technical Support Document

- Delaware , 7 DE Administrative Code 1125

–

Requirements for Preconstruction Revi ew, Section 3.0

– Prevention of Significant Deterioration of Air Quality /s/ FROM: Sharon McCauley , Environmental Protection Specialist

Office of Permits and Air Toxics (3AP10) TO: File THRU: Kathleen Anderson , Associate Director

Office of Permi ts and Air Toxics (3AP10)

I. BACKGROUND This State Implementation Plan (SIP) revision request governs the permits for constructing and significantl y modifying major stationary sources of air pollutants in Prevention of Significant Deterioration (PSD) areas located in Delaware . This regulatory revision was made effective as a legislative rule in Delaware on April 11, 2010

. These current Delaware regulations can be found in Regulation 1125, Section 3.0. This SIP revision, as proposed, will only replace the current regulations found in 1125 which establish NOx as a precursor to Ozone, but will keep in tact the formally approved Delaware SIP increments for NOx found in the Federal Register notice for Delaware dated July

27, 1993. Delaware’s proposed SIP submission addresses changes needed in the part C PSD permit program. This SIP submission also corrects deficiencies identified by EPA in the March 27, 2008 Federal Register notice entitled, “Completeness Findings for Section 110(a) State implementation Plans for the 8 hour Ozone National Ambient Air Quality Standards (1997 Ozone NAAQS)”, (73 FR 16205). EPA’s proposed approval of this SI P submission addresses Delaware’s compliance with the portion of C lean Air Act (C AA ) Section 110 (a)(2)(C) & (J) relating to the Part C permit program for the 1997 NAAQS Ozone NAAQS, because this proposed approval would approve regulating NOx as a precursor to ozone in Delaware’s SIP in accordance with the Federal Register notice dated November 29, 2005 (70 FR 71612) that finalized NOx as a precursor for ozone regulations set forth at 40 CFR 51.166 and in 40 CFR 52.21.2

EPA has determined that the current amendments to Delaware 's PSD permit program at 7 DE Administrative Code 1125

– Requirements for Preconstruction R eview, Section 3.0

– Prevention of Significant Deterioration of Air Qualit y, as submitted on April 1, 2010 , meet the minimum requirements of 40 CFR 51.166 and the CAA. This SIP proposal is being proposed as a full approvable revision to the Delaware SI P. No other changes to the currently approved SIP are being proposed for approval at this time. II. SUMMARY OF ACTION This rule establishes a state construction permit program consistent with the federal Clean Air Act’s Title I program and implementing regulations at 40 CFR §51.166, “Prevention of Significant Deterioration of Air Qualit y.” 7 DE Administrative Code 1125

– Requirements for Preconstruction Review, Section 3.0

– Prevention of Significant Deterioration of Air Qualit y is part of the SIP and s ets forth the criteria and procedures for major stationary sources to obtain a permit to construct, operate and/or modify a major stationary

source. As required b y 40 CFR Part 51, Subpart I

- “Review of New Sources and Modifications,” this rule adopts cri teria and procedures for the prevention of significant deterioration of air qualit y that are consistent with the governing federal regulation at 40 CFR §51.166. Promulgation of this rule by the Legislature is necessary for Delaware to fulfill its responsib ilities under 40 CFR Part 51 and the CAA, as amended. Revisions to the Delaware rule are simpl y adding new references to include NO x as a precursor to O zone to comport with federal counterpart language. The Delaware Department of Natural Resources and Envi ronmental Control has now submitted a final rule 7 DE Administrative Code 1125

– Requirements for Preconstruction Review, Section 3.0

– Prevention of Significant Deterioration of Air Quality as a proposed revision to the SIP. III. INFRASTRUCTURE De laware’s proposed SIP submission addresses changes needed in the part C PSD permit program. This SIP submission also corrects deficiencies identified by EPA in the March 27, 2008 Federal Register notice entitled, “Completeness Findings for Section 110(a) State implementation Plans for the 8 hour Ozone National Ambient Air Quality Standards (1997 Ozone NAAQS)”, (73 FR 16205). EPA’s proposed approval of this SI P submission addresses Delaware’s compliance with the portion of C lean Air Act (C AA ) Section 110 (a)(2)(C) & (J) relating to the Part C permit program for the 1997 NAAQS Ozone NAAQS, because this proposed approval would approve regulating NOx as a precursor to ozone in Delaware’s SIP in accordance with the Federal Register notice dated November 29, 2005 (70 FR 71612) that finalized NOx as a precursor for ozone regulations set forth at 40 CFR 51.166 and in 40 CFR 52.21. I V . PROGRAM REVIEW A. Delaware Submittal The Delaware submittal includes n ew references which were added to the State rule to3

in clude NO x as a precursor to O zone to comport with federal counterpart language. B. Public N otice Public notice was provided and a public hearing was held in the State of Delaware on January 5, 2010 and no comments were received regarding the changes made to Regulation 1125. C. Regulatory

Review of Proposed SIP DNREC Regulation 1125 Section 3.1 Definitions The following is a brief summary of the changes. Regulation 3.1 Modified Definition of Major Stationary Source was m odified to include NOx as a prec ursor to Ozone along with volatile organic compounds. DNREC Regulation 1125 Section 3. 7.7.1Review of Major Stationary Sources and Major Modifications

– Source Applicability and Exemptions The following is a brief summary of the changes. Section Status De scription Regulation 3.7.7.1 Modified No d e Minimus a ir quality level is provided for ozone.... DNREC Regulation 1125 Section 3. 11.1.5Air Quality Analysis The following is a brief summary of the changes. Section Status Description Regulation 3. 11.1.5 Mo dified Modified to include NOx as precursor to ozone.

Note: While reviewing the proposed SIP submittal it was noted that the previously approved NOx increments as approved in Federal Register n otice 58 FR 40065 dated July 27, 1993 were not found in the current submittal of Delaware’s regulation under 1125, Section 3.0 and Section 1.9 . EPA will propose approving the addition of NOx as a precursor to O zone to the regulations noted above, and will in effect , maintain the prior SIP approval of the NOx incr ements , as previously

approved in 1993

. V. RECOMMENDED AGENCY ACTION EPA recommends approving the revision to Delaware 's SIP to include changes to 7 DE Administrative Code 1125

– Requirements for Preconstruction Review, Section 3.0

– Prevent i on of Si gnificant Deterioration of Air Qualit y . As previously noted, this revision will establish NO x as a precursor to ozone in the State of Delaware SIP

.