**U NITED STATES ENVIRONMENTAL PROTECTION AGENCY**  **REGION III 1650 Arch Street**  **Philadelphia, Pennsylvania 19103**
**DATE:** February

22, 2012 **SUBJECT:** Technical Support Document

- Delaware ; Attainment Plan for the Delaware

Portion of the Philadelphia

- Wilmi ngton, Pennsylvania

- New Jersey
- Delaware (PA

- NJ
- DE) 1997 Fine Particulate Matter Nonattainment Area

/s/ **FROM:** Rose Quinto, Environmental Engineer

Office of Air Program Planning **TO:** File /s/ **THRU:** Cristina Fern andez, Associate Director

Office of Air Program Planning This document provides a technical review of a revision to the Delaware State Implementation Plan (SI P) submitted by the Delaware Department of Natural Resources and the Environment al Control ( DN REC ) on April 3, 2008 . This SI P revision address es the attainment plan of the 1997 annual fine particulate matter (PM 2.5 ) national ambient air quality standard (NAAQS) for the Delaware portion of the Philadelphia

- Wilmington , Pennsylvania

- New Jersey
Delaware (PA

- NJ
- DE) nonattainment area ( Philadelphia area)

. The attainment plan includes the Delaware portion of Philadelphia area ’s attainment demonstration, motor vehicle emission budgets (MVEBs) used for transportation conformity purposes, an analy sis of rea sonably available control measures (RACM) and reasonably available control technology (RACT), base y ear emission s inventor

y , and contingency

measures. This document also provides a technical review of a supplement to the April 3, 2008 submittal , submitte d by

DNREC on November 17, 2011 . This supplement submittal 1) replaces the onroad emissions budget in the April 3, 2008 submittal with a budget that is based on a new onroad mobile emissions model

– Motor Vehicle Emissions Simulator (MOVES) model ; 2) dem onstrates that the MOVES based mobile source budget is consistent with attainment of the PM 2.5 NAAQS by

2010 ; and 3) demonstrates that the contingency requirements of the CAA are met. This SI P revision only impacts PM 2.5 and nitrogen oxides (NOx) emissio ns and calculations. DNREC requested EPA to process this supplemental submittal in parallel with the April 3, 2008 submittal, while DNREC completes the public procedures necessary to submit the amended PM 2.5 attainment demonstration as a formal supplement to the April 3, 2008 submittal. If the proposed SI P revision is changed in areas oth er than those identified in the notice of proposed rulemaking action, EPA will evaluate those changes and may publish another notice of proposed rulemaking. I f no change s are made, EPA will publish a final rulemaking n otice on the2

revisions. The final rulemaking action by EPA will occur only

after the SI P revision has been adopted by Delaware and submitted formally to EPA for incorporation into the Delaware SI P.
**A. BA CKGROUND**  **I. Designation History**  On July 18, 1997 (62 FR 36852), the Environmental Protection Agency ( EPA ) established the 1997 PM 2.5 NAAQS, including an annual standard of 15.0 micrograms per cubic meter (  g/m 3 ) based on a 3

- ye ar average of annual mean PM 2.5 concentrations and a 24

- hour (or daily ) standard of 65  g/m 3 based on a 3

- ye ar average of the 98th percentile of 24

- hour concentrations. EPA established the standards based on significant evidence and numerous health studies demonstrating that serious health effects are associated with exposures to PM 2.5 . Following promulgation of a new or revised NAAQS, EPA is required by the Clean Air Act ( CAA ) to designate areas throughout the United States as att aining or not attaining the NAAQS; this designation process is described in section 107(d)(1) of the CAA. In 1999, EPA and S tate A ir Q uality A gencies initiated the monitoring process for the 1997 PM 2.5 NAAQS and by January 2001 , established a complete set of air quality monitors. On January

5, 2005 (70 FR 944) , EPA p romulgated initial air quality designations for the 1997 PM 2.5 NAAQS based on air quality monitoring data for calendar years 2001
- 20 03. On April 14, 2005 (70 FR 19844) , EPA p romulgated a supp lemental rule amending EPA’s initial designations , with the same effective date (April 15, 2005) as 70 FR 944

. As a result of th is supplemental rule, PM 2.5 nonattainment designations are in effect for 39 areas, comprising 208 counties within 20 s tates (an d the District of Columbia) nationwide, with a combined population of about 88 million. The Delaware portion of the Philadelphia area is included in the list of areas not attaining the 1997 PM 2.5 NAAQS
. The Delaware portion of the Philadelphia area consi sts of New Castle County

. Itshould be noted that on November 13, 2009 (74 FR 58688), EPA relabeled the existing designation tables in 40 CFR 81.308 to clarify the 1997 designations for the 24

- h our PM 2.5 NAAQS
. The designation for New Castle County was clarified as unclassifiable/attainment for the 1997 24

- hour PM 2.5 NAAQS
.
**II .**  **Clean Air Fine Particle Implementation Rule** On April 25 , 2007 (72 FR 20586) , EPA iss ued the Clean Air Fine Particle Implementation Rule for the 1997 PM 2.5 NAAQS . Th e “ PM 2. 5 Implementation R ule ” describes the CAA framework and requirements for developing S IP s for areas designated nonattainment for the 1997 PM 2.5 NAAQS
. An attainment plan must include a demonstration that a3

nonattainment area will meet the applicable NAAQS w ithin the t ime provided in the statute. This demonstration must include modeling (40 CFR 51.1007) that is performed in accordance with EPA modeling guidance (EPA

- 454/B

- 07
- 002, April 2007). Itmust also include supporting technical analy ses and descri ptio ns of all relevant adopted F ederal, s tate , and local regulations and control measures that have been adopted in order to provide attainment by the proposed attainment date

. For the 1997 PM 2.5 NAAQS, an attainment plan must show that a nonattainment are a will attain the 1997 PM 2.5 NAAQS as expeditiously as practicable, but within five years of designation (i.e. attainment date of April 2010 based on air quality data for 2007

- 2009)

. I f the area is not expected to meet the NAAQS by April 2010, a s tate may request to extent the attainment date by

one to five years based upon the severity of the nonattainment problem or the feasibility of implementing control measures (section 172(a)(2) of the CAA ) in the specific area

. For EPA to approve an extension of the attainment date beyond 2010, the state must provide an analy sis to support the request and demonstrate that the attainment date is as expeditious as practicable for the area given the facts and circumstances of the area and consistent with the statutory c riteria for an extension. For each nonattainment area, the s tate must demonstrate that it has adopted all RACM , including all RACT as needed to provide for attainment of the PM 2.5 standards in the area “ as expeditiously

as practicable. ” The PM 2.5 Implem entation R ule provides guidance for making these RACM and RACT determinations. Any measures that are necessary to meet these requirement s that are not already F edera lly promulgated or in an EPA
- approved part of the state’s SI P must be submitted as part of the s tate’s attainment plan

. Any s tate measures must meet the applicable statutory

and regulatory

requirements, and in particular, must be Federally enforceable. The PM 2.5 Implementation R ule also includes guidance on pollutants that s tates must addres s in their attainment plans

. Section 302(g) of the CAA authorizes EPA to regulate criteria pollutants and their precursors. Inthe case of PM 2.5 , the main chemical precursors are sulfur dioxide (SO 2 ), NO x , ammonia (NH 3 ), and volatile organic compounds (V OCs ). The effect of reducing emissions of precursor pollutants that contribute to PM 2.5 concentrations varies by area, however, depending on PM 2.5 composition, emission levels, and other area

- specific factors. For this reason, the PM 2.5 Implementation R ul e provided guidance recommending that states elect to control direct PM 2.5 emissions and the precursor or precursors that would be most effective for attaining the NAAQS within the specific area, based upon an appropriate technical demonstration. Inacco rdance with the PM 2.5 Implementation R ule, direct PM 2.5 emissions means “ solid particles emitted directly

from an air emissions source or activity , or gaseous emissions or liquid droplets from an air emissions source or activity which condense to form part iculate matter at ambient temperatures. Direct PM 2.5 emissions include elemental carbon, directly emitted organic4

carbon (OC) , directly

emitted sulfate (SO 4 ) , directly emitted nitrate (NO 3 ) , and other inorganic particles (including but not limited to cr ustal material, metals, and sea salt). ” The PM 2.5 Implementation R ule requires all s tates to addres s SO 2 as a PM 2.5 attainment plan precursor and to evaluate SO 2 for possible control measures in all PM 2.5 nonattainment areas. States are also required to address NO x as a PM 2.5 attainment plan precursor and evaluate reasonable controls for NO x in PM 2.5 attainment plans, unless the s tate and EPA make a finding that NO x emissions fro m sources in the s tate do not significantly contribute to PM 2.5 concentration s in the relevant nonattainment area. Although current scientific information shows that certain VOC emissions are precursors to the formation of secondary organic aerosol, and significant progress has been made in understanding the role of gaseous organi c material in the formation of organic particular matter ( PM ) , this relationship remains complex. Further research and technical tools are needed to better characterize emissions invento ries for specific VOC compounds and to determine the extent of the co ntribution of specific VOC compounds to organic PM mass. Because of these factors, the PM 2.5 Implementation R ule did not require s tates to address VOCs as PM 2.5 attainment plan precursors and evaluate them fo r control measures, unless the s tate or EPA mak es a finding that VOCs significantly contribute to a PM 2.5 nonattainment problem in the s tate or to other downwind air quality concerns. The PM 2.5 Implementation R ule describes the formation of particles related to NH 3 emissions, which is a complex, nonli near process. Though recent studies have improved our unde rstanding of the role of NH 3 in aerosol formation, ongoing research is needed to better describe the relationships between NH 3 emissions, particulate matter concentrations, and related impacts. Al so, area specific data is needed to evaluate the effectiveness of reducing NH 3 emissions on reducing PM 2.5 concentrations in different areas , and to determine where NH 3 decreases may

increase the acidity

of particles and precipitation. For these reasons, in the PM 2.5 Implementation R

ule, NH 3 is presumed not to be a PM 2.5 attainment plan precursor, meaning that the s tate is not required to address NH 3 in its attainment plan or evaluate sources of NH 3 emissions for reduction measures , unless the state or EPA makes a finding that NH 3 significantly contributes to a PM 2.5 nonattainment problem in the area or to other downwind air quality concerns. The presumpti ve inclusion of NO x and the presumptive exclusion of VOC and NH 3 as attainment plan precursors can be reversed based on an acceptable technical demonstratio n for a particular nonattainment area by the s tate or EPA. Such a demonstration should include information from multiple sources, including results of speciation data analy ses, air quality modeling stu dies, chemical tracer studies, emission inventories, or special intensive measurement studies to evaluate specific atmospheric chemistry in an area

. S

ee PM 2.5 Implementation R ule for more information

.5

The PM 2.5 Implementation R ule also provided guidance on other elements of a s tate’s attainment plan, including, but not limited to, consideration of emission inventories, contingency measures, and MVEBs used for transportation conformity purposes. There are, however, three aspects of the PM 2.5 Implementati on Rule for which EPA received petitions requesting reconsideration. These pertain to the presumption or advance determination that compliance with the requirements of the Clean Air I nterstate Rule (CAI R) automatically

satisfie s the requirements for RACT or RACM for NOx or SO 2 emissions f ro m electric generating unit (EGU) sources participating in regional cap and trade programs ; the suggestion in the preamble that the economic feasibility element of a RACT determination for EGUs should include consideratio n of whether the cost of a measure is reasonable in light of the benefits; and the policy

described in the preamble of allowing certain emissions reductions f ro m outside the nonattainment are a to be credited as meeting the RFP requirement. EPA has grant e d these petitions

. The attainment plan for the Delaware portion of the Philadelphia area did not rely on any of these aspects of the rule. CAI R, as originally

promulgated, requires significant reductions in emissions of SO 2 and NO x to limit the interstate transport of these pollutants. In 2008, however, the D.C. Circuit remanded CAI R back to EPA. See North Carolina v. EPA, 550 F.3d 1176. The Court found CAI R to be inconsistent with the requirements of the CAA, North Carolina v. EPA, 531 F.3d 896 (D.C. Cir. 2008), but ultimately remanded the rule to EPA without vacatur because it found that “allowing CAI R to remain in effect until it is replaced by a rule consistent with [the court’s] opinion would at least temporarily preserve the environmental values covered by CAI R,” North Carolina v. EPA, 550 F.3d at 1178. In response to the court’s decision, EPA has issued a new rule to address interstate transport of NOx and SO 2 in the eastern United States (i.e., the Transport Rule, also known as the Cross

- State Air Pollution Rule). See 76 FR 48208, August 8, 2011. In the Transport Rule, EPA finalized regulatory changes to sunset CAI R and the CAI R Federal Implementation Plans ( FIPs ) for control periods in 2012 and beyond. See 76 FR 48322. On December 30, 201 1 , the D.C. Circuit issued an order addressing the status of the Transport Rule and CAI R in response to motions filed by numerous parties seeking a stay of the Transport Rule pending judicial review. In that order, the D.C. Circuit stayed the Transport Rule pending the court’s resolution of the petitions for review of that rule in EME Homer Generation, L. P. v. EPA (No. 11

- 1302 and consolidated cases). The court also indicated that EPA is expected to continue to administer the CAI R in the interim until the court rules on the petitions for review of the Transport Rule. Under the circumstances set forth above, EPA believes it is appropriate to finalize its proposed approval of the Delaware portion of the Philadelphia area attainment plan demonstration

. Although the Court has stayed the implementation of the Transport Rule at this time, EPA believes that the rule has a strong legal basis. To the extent that the current status of CAI R and the Transport Rule affect any of the criteria for approval of thi s area ’s attainment plan, we believe that the ongoing implementation of CAIR during the period of the stay , coupled with6

the promulgation of the Transport Rule, provide adequate assurance of the components of the attainment plan . Thus, for purposes of thi s proposed approval , EPA believes that the state may rely on the combination of CAI R, which remains in place temporarily during the period of the stay , and the Transport Rule which has been promulgated to replace the CAIR. When the c ourt issues its ruling on the merits of the Transport Rule, EPA will re

- evaluate its position as necessary and take such further action as is appropriate.
**III. Determinations of Attainment**  The data in Table 1 indicates that the Delaware portion of the Philadelphia area is m eeting the 1997 annual PM 2.5 NAAQS. In addition, Table 2 shows that the Delaware portion of the Philadelphia area continues to attain the 1997 annual PM 2.5 NAAQS by 2010. However, this action does not determine that the Delaware portion of the Philadelph ia area has attained the 1997 annual PM 2.5 NAAQS and the information is included here only to support Delaware ’s demonstration that the Delaware portion of the Philadelphia area could meet the attainment date of April 5, 2010, and continues to attain based on the most recent data available. EPA is tak ing action to formally

determine the Delaware portion of the Philadelphia area’s attainment of the 1997 annual PM 2.5 NAAQS in a separate action. **Table 1. 2009 Annual Averaged PM 2.5**  **Design Value County**  **Site N ame**  **Site Number Design Value (μg/m**  **3 )**  New Castle Bellefonte 10003 1003 12.3 New Castle Lums Pond 10003 1007 11.4 New Castle Newark 10003 1012 12.5 New Castle ML K 10003 2004 13.3 **Table 2. 2008 -**  **2010 Monitored Annual**  **Design Values County**  **Site Name Site Nu**  **mber Design Value (μg/m**  **3 )**  **2008 2009**  **2010** New Castle Bellefonte 100031003 12.9 12.2 11.1 New Castle Lums Pond 100031007 11.8 11.3 10.5 New Castle Newark 100031012 12.9 12.2 11.2 New Castle ML K 100032004 14.2 13.0 11.7
**B . COMPONENTS OF**  **DELAWARE ’S**  **ATTAINMENT PLAN** Inaccordance with section 172 (c) of the CAA and the PM 2.5 Implem entation R ule , the attainment plan submitted on April 3 , 20 08 by DNREC for the Delaware portion of the Philadelphia area include d: (1) an emission s inventor y for the plan’ s base year (2002) ; (2) an attainment demonstration ; and (3) MVEBs for the attainment year. The attainment demonstration includes: (a) technical analy ses that locate, identify , and quantify sources of7

emissions contributing to violations of the 1997 annual PM 2.5 NAAQS; (b) analy ses of future ye ar emissions r eductions and air quality improvements expected to result f rom national and local programs from new measures to meet RACM/RACT requirements ; (c) adopted emission reduction measures with sche dules f or implementation; and (d ) contingency measures for NO x , SO 2 and direct PM 2.5 to be implemented if the area did not meet RFP or did not attain the standard by

the attainment date

. On November 17, 2011 , DNREC submitted a supplement to the April 3, 200 8 submittal. This supplement submittal 1) replaces the onroad emissions budget in the April 3, 2008 submittal with a budget that is based on a new onroad mobile emissions model

– MOVES model ; 2) demonstrates that the MOVES based mobile source budget is c onsistent with attainment of the PM 2.5 NAAQS by

2010 ; and 3) demonstrates that the contingency requirements of the CAA are met. This SI P revision only impacts PM 2.5 and NOx emissions and calculations. To analy ze future ye ar emissions reductions and a ir quality improvements, Delaware use d local, regional , and national modeling analy ses that have been developed to support Federal and lo cal emission reduction programs. This modeling was performed in accordance with EPA’s “Guidance on the Use of Models and Other Analy ses for Determining Attainment of Air Quality Goals for Ozone , PM 2.5 , and Regional Haze , ” (EPA

- 454/B

- 07
- 002, April 2007).
**C .**  **EPA’S REVIEW AND TECHNICAL INFORMATION** The following EPA analy sis of the PM 2.5 attainment plan for the Delaware portion of the Philadelphia area addresses all required elements of a PM 2.5 attainment plan as described in the PM 2.5 Implementation R

ule (72 FR 20586). **I. Pollutants Addressed**  Inaccordance with policies described in the PM 2.5 Implementation Rule, Delaware ’s PM 2.5 attainment plan evaluates emissions of direct PM 2.5 , SO 2 , and NOx in the Delaware portion of the Philadelphia area

. With regard to evaluation of PM 2.5 precursors , the PM 2.5 Implementation Rule requires that SO 2 be evaluated for controls in all nonattainment areas, and describes general presumptive policies for NOx, NH 3 , and VOCs. For NOx, states are required to address NOx as a PM 2.5 attainment plan precursor and evaluate reasonable controls for NOx in PM 2.5 attainment plans, unless the s tate makes a finding that NOx emissions in the s tate do not significantly

contribute to PM 2.5 concentrations in the area. For NH 3 , b ecause of uncertainties regarding NH 3 emission inventories and the efficacy of ammonia control technologies , the final rul e set s forth the presumption that NH 3 is not a PM 2.5 precursor and that s tates are not required to address NH 3 in their attainment plan. Similarly , VOC emissions are presumed not to be an attainment plan precursor because of uncertainties regarding the ro le of VOC in secondary organic aerosol formation. Delaware ’s attainment plan does not reverse any of th ese presumption s .8

**II. E**  **missions Inventory Requirements** Section 172(c)(3) of the CAA requires s tates to develop emissions inventories of point, area, o nroad mobile, and nonroad mobile sources for their attainment demonstrations. These inventories provide a detailed accounting of all emissions and emissions sources by precursor or pollutant. Inaddition, inventories are used to model air quality to demo nstrate that attainment of the 1997 PM 2.5 NAAQS as expeditiously as practicable, and if an attainment extension beyond 2010 is needed to support the need for such an extension. Emissions inventory guidance was provided in the April 1999 document “Emission s Inventory Guidance for Implementation of Ozone and Particulate Matter NAAQS and Regional Haze Regulations,” (EPA

–454/R

– 99

– 006), which was updated in November 2005 (EPA

–454/R

– 05

– 001). Emissions reporting requirements were provided in the 2002 Consolidate d Emissions Reporting Rule (CERR) (67 FR 39602). On December 17, 2008 (73 FR 76539), EPA promulgated the Air Emissions Reporting Requirements (AERR) to update emissions reporting requirements in the CERR, and to harmonize, consolidate and simplify data re porting by

states. Inaccordance with the A ERR and the November 2005 guidance, the PM 2.5 Implementation R

ule required s tates to submit inventory information on directly

emitted PM 2.5 and PM 2.5 precursors and any additional inventory

information needed to support an attainment demonstration. PM 2.5 is comprised of filterable and condensable emissions. Condensable particulate matter (CPM) can comprise a significant percentage of direct PM 2.5 emissions from certain sources, and are required to be included in national emission inventories based on emission factors. Test Methods 201A and 202 are available for source

- specific measurement of condensable emissions. However, the PM 2.5 Implementation Rule acknowledged that there were issues and concerns related to availability and implementation of these test methods as well as uncertainties in existing data for condensable PM 2.5 . In recognition of these concerns, EPA established a transition period during which EPA could assess possible revisions to available tes t methods and to allow time for s tates to update emissions inventories as needed to address direct PM 2.5 , including condensable emissions. Because of the time required for this assessment, EPA recognized that s tates would be limited in how to effectively address CPM emissions, and established a period of transition, up to January 1, 2011, during which s tate submissions for PM 2.5 were not required to address CPM emissions. Amendments to these test methods were proposed on March 25, 2009 (74 FR 12969), and finalized on December 21, 2010 (75 FR 80118). The amendments to Method 201A add ed a particle

- sizing device for PM 2.5 sampling , and the amendments to Method 202 revise d the sample collection and recovery procedures of the method to reduce the formation of reaction artifacts that could lead t o inaccurate measurements of CPM emissions

. The period of transition for establishing emissions limits for condensable direct PM 2.5 ended on January

1, 2011. PM 2.5 submissions made during the transition period are not required to address CPM emissions; however, s tates must address the control of direct PM 2.5 emissions,9

including condensable emissions, with any new action taken after this January 1, 2011. Delaware submitted the Delaware portion of the Philadelphia area attainment plan prior to January 1, 2011 and did not consider condensables. InJuly 2008, EarthJustice filed a petition requesting reconsideration of EPA ’s transition period for CPM emissions provided in the PM 2.5 Implementation Rule. In January 200 9, EPA decided to allow states that have not previously addressed CPM to continue to exclude CPM for PSD permitting during the transition period. This TSD reflects a review of Delaware ’s submittal based on current EPA guidance as described in the PM 2.5 Implementation Rule. More information and the review and evaluation of the methods used for the emissions inventory submitted by Delaware are found in section 3 of Delaware ’s attainment plan submittal and a TSD entitled, “Technical Support Document for Emi ssions Inventories for the Delaware No n attainment Area PM 2.5 SI P Base Year Inventory ,” dated June 16, 2010
. **1. 2002 Base Year Emission Inventories**  An emission inventory

is an estimate of the emissions from sources in a particular area. DNREC developed an emission inventory for 2002, which is the base year for attainment planning purposes with respect to 8

- hour ozone and PM 2.5 SI Ps and for planning purposes with respect to the regional haze SI Ps. The 2002 base year inventory includes the pollutants PM 10 , P M 2.5 , SO 2 , NOx, VOC, and NH 3 . The inventory consists of four sectors: stationary point sources, stationary

area sources, highway

vehicle sources and nonroad sources. The Mid

Atlantic/Northeast Visibility Union (MANE

- VU) compiled a regional inventory fro m the emission inventories of the Northeastern and Mid

- Atlantic states. This regional inventory was used to perform the regional modeling analy sis used in the Delaware ’s air quality management effort to attain the 8

- hour ozone NAAQS and the PM 2.5 NAAQS, and to prepare the regional haze plan. Stationary

point source inventory

represents facility

- specific data for Delaware’s larger stationary sources. Point sources ty pically include large industrial, commercial and institutional facilities. Manufacturing facilities, within the industrial sector, comprise the majority of all reporting point sources. The institutional sector includes hospitals, universities, prisons, military bases, landfills and wastewater treatment plants. Point source emissions data are submitted to Air Quality

Management Section (AQMS) by the facilities using Terminal Server Satellite **i**
STEPS software. **i**
- STEPS are the point source emission inventory electronic data management sy stem. Area sources represent a large and diverse set of individual emission source categories. An area source category

is either represented by

small facilities too numerous to individually inventories, such as restaurants (commercial cooking), or is a common activity , such as fugitive dust fr o m construction and agricultural production. Emissions from area sources were estimated at the county

level. For the area sources, DNREC provided an inventory that contained10

estimations of emissions by multiplying an emission factor by some known indicator or activity le vel for each category

at the county

level. These emissions are calculated on an annual basis. Various sources of emission factors or methodologies were used, including EPA’s AP

- 42, the Factor Information Retrieval Sy stem (FI RE), EPA’s Emissions Inventory Improvement Program, Volume I II, documented projects performed by the California Air Resource Board, and projects performed by

the Mid

- Atlantic Regional Air Management Association (MARAMA). Area source estimates were provided by source classification cod e (SCC). Highway vehicles, which include passenger cars and light

- duty trucks, other trucks, buses , and motorcycles, are o nroad mobile source emissions inventory that was developed using the most current version of EPA’s highway mobile so urce emissions mo del MOBI LE6.2 and link

- level vehicle miles traveled (VMT) data for each county from the Delaware Department of Transportation (DelDOT). The emission factors developed using MOBI LE6.2, were by month, using monthly

temperature and fuel property data. DNREC provided MOBI LE6.2 input and output files for review. DNREC provided annual mobile emissions values in tons per year (tpy ) and were provided by

SCC. Nonroad sources, which encompass a diverse collection of engines, including , but not limited to , outdoor power equipment, recreational vehicles, farm and construction machinery , lawn and garden equipment, industrial equipment, recreational marine vessels, commercial marine vessels, l ocomotives, ships, and aircraft were estimated using the EPA NONROAD 2005 mo del. The emissions inventory for the base year, 2002, was developed in accordance with EPA guidance, “Emissions Inventory Guidance for Implementation of Ozone and Particulate Matter National Ambient Air Quality Standards and Regional Haze Regulations, EPA

- 454/R

- 05
- 001, August 2005, updated November 2005.” Table s 3 , 4 and 5 summarize the emissions for 2002. **Table 3. 2002 Annual Emissions by County (t**  **py )**  **County PM**  **10 PM**  **2.5 SO**  **2 NOx**  **NH 3**  **VOC** Kent 3991 1097 4062 10314 2841 5296 New Castle 8604 34 30 50237 30748 1384 18062 Sussex 6758 2575 25552 16060 10057 10251 **Total 19353**  **7102 79852**  **57122 14284**  **33610 Tabl**  **e 4 . 2002**  **Statewide Annual Emissions**  **(t py**  **) Source Sector**  **PM 10**  **PM 2.5**  **SO 2**  **NOx NH**  **3 VOC**  Point 3859 3161 73708 16372 179 4773 Area 13870 2580 1330 2427 13194 10254 Onroad 581 415 584 21341 903 10564 Nonroad 1043 946 4230 16982 8 8019 **Total 19353**  **7102 79852**  **57122 14284**  **33610**11

**Table 5 . 2002**  **New Castle County Annual Emissions**  **(t py**  **) Sourc**  **e Sector PM**  **10 PM**  **2.5 SO**  **2 NOx**  **NH 3**  **VOC** Point 2168 1733 47070 9157 118 2687 Area 5674 1073 780 1513 710 6198 Onroad 304 209 326 11799 552 5762 Nonroad 458 415 2061 8279 4 3415 **Total 8604**  **3430 50237**  **30748 1384**  **18062** The review and evaluation of the methods used for the emissions inventory submitted by Delaware are found in the attainment plan submittal (section 3 ) and a TSD entitled “Technical Support Document for Emissions Inventories for the Delaware Nonattainment Area PM 2.5 S IP Base Year Inventory ,” dated June 16, 2010. **2. 2009 Projected Emission Inventories**  Table s 6 and 7 summarize the emissions expected in 2009. These emissions take activity and emissions growth and/or controls from 2002 into account. Section 4 and Appendix 4

- 3 of the Delaware ’s attainment plan, relating to emissions projections, contains documents that describe the methodologies used to project the 2002 baseline emissions to 2009. **Table 6**  **. 2009 Projected Emissions ( tpy**  **) , i.e., Contr**  **ol Strategy Emissions County**  **NH 3**  **NOx PM**  **10 PM**  **2.5 SO**  **2 VOC**  Kent 2887 7799 3253 989 3664 4230 New Castle 1466 21807 6039 3015 14135 13887 Sussex 10106 11591 5731 2571 11724 7558 **Totals 14459**  **41197 15023**  **6575 29523**  **25675 Ta**  **ble 7**  **. CMAQ Modeled 2009 Emissions ( tpy**  **), i.e .**  **, Attainment Targets County**  **NH 3**  **NOx PM**  **10 PM**  **2.5 SO**  **2 VOC**  Kent 2887 7799 3253 989 3664 4230 New Castle 1466 21807 6039 3015 14135 13887 Sussex 10106 11591 5731 2571 11724 7558 **Tot als**  **14459 41197**  **15023 6575**  **29523 25675** 
**3. Growth Projections Methodologies**  Growth projections m ethodologies describe the data, methods and assumptions utilize in developing estimates of emissions changes between 2002 and the milestone year 2009. Appen dix 4
- 1 of the Delaware ’s attainment plan contains the technical support document entitled, “Development of Emission Projections for 2009, 2012, and 2018 for Non

- EGU Point, Area, and Nonroad Sources in the MANE

- VU Region,” developed by MARAMA. Th is12

docume nt provides detail on the specific factors, control assumptions, and implementation schedules used in the emission projection calculations for each source category

. **III. Modeling**  All attainment demonstrations must include modeling that is performed in accordance with EPA’s “Guidance on the Use of Models and Other Analy ses for Demonstrating Attainment of Air Quality

Goals for Ozone, PM 2.5 , and Regional Haze” (EPA

- 454/B

- 07
- 002, April 2007)

. Modeling may

be based on national (e.g., EPA), regional (e.g., O zone Transport Commission), local modeling, or a combination th ereof, if appropriate. A description of modeling used to support Delaware ’s attainment demonstration follows. More detailed information on the modeling is discussed in a TSD entitled, “Techni cal Support Document for the Modeling and Weight of Evidence Portion s of the Delaware’s State Implementation Plan for Attainment of the PM 2.5 Annual NAAQS ,” dated June 15, 2010 and s ection 6 of the Delaware ’s attainment plan. **Conceptual Model Description** A conceptual model describes how weather patterns affect the formation and transport of PM 2.5 , accounting for emissions and photochemistry

. The conceptual model for Delaware’s attainment plan is described in a document prepared by the Northeast States f or Coordinated Air

- Use Management (NESCAUM) final report entitled , “ The Nature of the Fine Particle and Regional Haze Air Quality Problems in the MANE
- VU Region: A Conceptual Description (2006) , ” for the use by the Ozone Transport Commission (OTC) member states which provides the conceptual description of PM 2.5 issues in the OTC states and is consistent with EPA’s guidance. The NESCAUM document contains a conceptual description that explains how elevated regional PM 2.5 peak concentrations in the summer di ffer significantly from the largely

urban peak concentrations observed during winter. On average, summertime concentrations of sulfate in the northeastern United States are more than twice that of the next most important fine particle constituent, organic carbon (OC), and more than four times the combined concentration of nitrate and black carbon (BC) constituents. Episodes of high summertime sulfate concentrations are consistent with stagnant meteorological flow conditions upwind of the Delaware portion of the Philadelphia area and the accumulation of airborne sulfate (via atmospheric oxidation of SO 2 ) followed by

long

- range transport of sulfur emissions from industrialized areas within and outside the area. National assessments have indicated that in th e winter, sulfate levels in urban areas are higher than background sulfate levels across the eastern U.S., indicating that the local urban contribution to wintertime sulfate levels is significant relative to the regional sulfate contribution from long

- rang e transport. A network analy sis for the winter of 2002 suggests that the local enhancement of sulfate in urban areas of the MANE

- VU region ranges from 25 to 40% and that13

the long

- range transport component of PM 2.5 sulfate is still the dominant contributor in most eastern cities. Inthe winter, urban OC and sulfate each account for about a third of the overall PM 2.5 mass concentration observed in Philadelphia and New York City areas. Nitrate also makes a significant contribution to urban PM 2.5 levels obse rved in the northeastern United States during the winter months. Wintertime concentrations of OC and nitrate in urban areas can be twice the average regional concentrations of these pollutants, indicating the importance of local source contributions. Thi s is likely because winter conditions are more conducive to the formation of local inversion layers which prevent vertical mixing. Under these conditions, emissions from tailpipe, industrial and other local sources become concentrated near the Earth’s sur face, adding to background pollution levels associated with regionally transported emissions.
**The Model U**  **sed in the Attainment Demonstration** By agreement of OTC, the New York State Department of Environmental Conservation (NYSDEC) ran the Community M ulti

- scale Air Quality

Model (CMAQ) for the states in the northeast ozone transport region that includes Delaware . EPA agrees CMAQ is appropriate for this modeling demonstration. The inputs to the model are described in section 6 of the attainment plan s ubmittal. **Meteorological Time Periods Used in the Modeling** Since the Delaware portion of the Philadelphia area’s attainment demonstration used a resource intensive photochemical grid model, EPA accepts the use of single, recent representative year to be used for an annual simulation. Two factors were used in selecting 2002 as the representative year: the observed annual mean concentrations of PM 2.5 are close to the 3
- ye ar observed design value at all, or most monitoring sites, and the pattern of qua rterly mean values is similar to the pattern of quarterly mean concentrations averaged over 3 years. **Meteorological Data Used in the Air Quality Model** The OTC modeling committee decided to use a prognostic meteorological model that provides life

- like meteorological inputs to the photochemical grid model. The Pennsylvania State University

/National Center for Atmospheric Research Mesoscale Meteorological Model (MM5) version 3.6 was chosen for the modeling analy sis. The MM5 model provides a reasonable r epresentation of weather conditions at th e surface and aloft.14

**Domain of the Model, Horizontal/Vertical Resolution and the Initial and Boundary Conditions**  The model ing domain extends from Maine to Florida and out in the Atlantic Ocean on the east and we st to the Mississippi River. The size of the modeling domain was made large enough to include all emission sources that affect PM 2.5 concentration in the northeastern United States

. Even this boundary

is defined by

a larger photochemical model ing doma in th at cover s much of North America

. Over the northeastern United States, the model used 12 kilometer grid cells

. The Ph iladelphia area i s included in the 12 kilometer grid cell area. T he OTC Modeling Committee used a 12

- kilometer grid size for the are as in and near its states to provide a fine enough grid resolution to adequately capture the PM patterns experienced in the ozone transport region (OTR). Outside the local area s the grid resolution used in the modeling is 36 kilometers

. The selection of model domains and horizontal grid resolution was deemed acceptable to EPA. Vertical resolution is the number of layers and the size of each layer in the model. The layers in the photochemical grid model were set up to be compatible with the model that produced weather conditions for the photochemical grid model. T he vertical resolution used in the modeling exercise followed EPA’s modeling guidance and therefore adequately represent s the atmosphere where PM 2.5 is emitted, forms and is transported.
**E mission**  **s Used in the Air Quality Model** The emissions data for 2002 were generated by individual states within the OTR and assembled and processed through MANE
- VU, a Regional Planning Organization (RPO). These emissions were then processed by NYSDEC usi ng the sparse matrix operator kernel emissions (SMOKE) emissions processor to provide CMAQ compatible inputs. The 2002 emissions for the non

- OTR areas within the modeling domain were obtained from the corresponding RPOs and were processed using SMOKE, in manner similar to that of the OTR emissions. The OTR states, through MANE

- VU, contracted MACTEC Federal Programs (called Contractor) to develop 2009, 2012 , and 2018 inventories based on 2002 inventories that the states had previously developed for the bas e - ye ar model work. The Contractor, in consultation with the states, developed the necessary

growth and control factors and applied to the 2002 inventory

. **Base Case Run Model Performance Evaluation** NYSDEC performed a model evaluation for the OTC to determine how well CMAQ reproduced the 2002 PM 2.5 concentrations. CMAQ was employed to simulate PM 2.5 for the calendar year 2002. A review of PM 2.5 and its individual species was conducted for the study domain. Several observations were made with respec t to model performance: 1) a pproximately 80

– 90 percent of organic mass (OM) is in the primary fraction ; 2) CMAQ captures seasonal variation in SO 4 well ; 3) CMAQ appears to overestimate primary PM 2.5 components, especially15

during colder months ; and 4) CMAQ appears to underestimate secondary OM during the summer. These issues are not of great regulatory concern since attainment tests are based on the application of relative response factors. Therefore, the regional and local model performance is accep table for PM 2.5 . While there are some differences between the spatial data between sub

regions, there is nothing to suggest a tendency for the model to respond in a sy stematically different manner between regions. Examination of the statistical metrics b y sub

- region confirms the absence of significant performance problems arising in one area but not in another, building confidence that the CMAQ modeling sy stem is operating consistently across the full OTC domain. This confidence in the modeling results a llows for the modeling sy stem to be used to support the attainment plan to meet the 1997 annual PM 2.5 NAAQS.
**2009 C ontrol**  **Case M odel**  **ing and Modeled Attainment Test** As previously

mentioned, the Delaware portion of the Philadelphia area has an attainment date of April 5, 2010. The PM 2.5 NAAQS include an annual standard of 15 μg/m 3 based on the 3
- ye ar average of annual mean PM 2.5 concentrations. The purpose of a modeling assessment is to determine if control strategies currently being implemented (“on the books”) will lead to attainment of the annual average NAAQS for PM 2.5 by 2009. The modeling is applied in a relative sense, similar to the 8

- hour ozone attainment test. However, the PM 2.5 attainment test is more complicated and reflects the fact that PM 2.5 is a mixture. In the test, ambient PM 2.5 is divided into major components, with a separate relative response factor (RRF) and future design value (DVF) calculated for each of the PM 2.5 components. Since the attainment test is calculated on a per sp ecies basis, the attainment test for PM 2.5 is referred to as the Speciated Modeled Attainment Test (SMAT ).
**Annual SMAT Results** Table 8 presents the results of the annual SMAT results for the Philadelphia area. The SMAT results demonstrate that the proj ected average annual arithmetic mean PM 2.5 concentration calculated at each Federal Reference Method (FRM) monitor attains the annual PM 2.5 NAAQS . Specifically , all calculations are less than15 μg/m 3 . Table 8 presents the results of the annual SMAT results for a suite of regional modeling runs conducted by OTC each representing OTB/OTW

– “On the Books, On the Way” control measures. All runs dem onstrate compliance with the annual PM 2.5 NAAQS.16

**Table 8**  **. Annual SMAT Results for**  **Philadelphia -**  **Wilmington, PA -**  **NJ -**  **DE PM**  **2.5 Nonattainment Area**  **On -**  **The -**  **Books -**  **On -**  **The -**  **Way Control Measures**

Insummary , the basic photochemical grid modeling, presented in the Delaware’s attainment plan, used the methods recommended in EPA’s modeling guidance. When EPA’s attainment test is applied to the modeling results, the 2009 annual

- average PM 2.5 design value is predicted to be 13. 3 μg/m 3 in the Philadelphia area. Therefore, based on EPA’s modeled attainment test, the Philadelphia area reached attainment of the annual average PM 2.5 standard in 2009 before the attainment date of April 5, 2010. **Supplemental Analyses and Weight of E vidence (WOE) Determination**  EPA’s modeling guidance states that additional analy ses are recommended to determine if attainment will be likely , even if the modeled attainment test is “passed.” The guidance recommends supplementary analy ses in all cases. EPA’s modeling guidance d escribes how to use a photochemical grid model and additional analy tical methods to complete a WOE analy sis to estimate if emissions control strategies will lead to attainment. A WOE analy sis is a supporting analy sis that helps to determine if the results of the photochemical modeling sy stem are correctly

(or not correctly

) predicting future air quality

. All models, including the CMAQ, model have inherent uncertainties. Over or under prediction may

result from uncertainties as sociated with emission inventories, meteorological data, and representation of PM 2.5 chemistry in the model. Therefore, EPA modeling guidance provides for other evidence to address these model uncertainties so that proper assessment of the **AIRS ID Site** 

**Name County**  **State 2000**  **- 2004**  **Baseline Design Value 2009**  **Q1 Q2**  **Q3 Q4**  **DVF** 420170012 Bristol Bucks PA 14.14 13.69 14.73 13.85 12.1 420290100 New Garden Chester PA 14.39 14.73 16.36 13.76 12.4 420450002 Chester Delaware PA 15.07 15.96 16.34 13.74 13.3 420910013 Norristown Montgomery PA 12.68 13.62 13.96 12. 34 11.3 421010004 AMS Lab Philadelphia PA 15.99 14.01 15.95 13.82 12.9 421010024 NE Airport Philadelphia PA 13.58 13.63 14.95 12.96 11.9 421010047 Broad Street Philadelphia PA 16.59 16.45 15.80 15.37 13.5 421010136 Elmwood Philadelphia PA 15.70 14.20 1 5.27 12.99 12.7 100031003 Bellefonte New Castle DE 14.87 15.16 15.50 13.13 12.6 100031007 Lums Pond New Castle DE 13.16 14.37 16.05 10.66 11.3 100031012 Newark New Castle DE 15.27 14.91 16.53 13.14 12.6 100032004 MLK New Castle DE 16.41 15.40 17.61 14. 04 13.3 340070003 Camden Camden NJ 13.99 14.54 15.76 12.47 12.3 340071007 Pennsauken Camden NJ 13.99 14.00 14.75 13.59 12.3 40155001 Gibbstown Gloucester NJ 13.92 13.43 15.08 11.39 11.717

probability

to attain the applicable standards can be made. EPA modeling guidance states that those modeling analy ses that show that attainment with the NAAQS will be reached in the future with some margin of safety (i.e., estimated concentrations below 14.5 μg/m 3 for annual PM 2.5 and 62 μg/m 3 for 24

- hour PM 2.5 ) need more limited supporting material. Due to the fact that the modeling results presented in Table 8 , fall below the aforementioned “weight of evidence” thresholds established by EPA, a limited supplemental an aly sis was deemed necessary to support the 2009 attainment demonstration. DNREC ’s supporting evidence includes a brief summary of the modeling demonstration, recent trends in the Philadelphia area’s monitoring data and a brief analy sis of some of the larg est SO 2 sources within the nonattainment area ( s ection 6 of Delaware ’s attainment plan)

.
**I V.**  **Reasonably Available Control Measures/Reasonably Available Control Technology 1**  **. Requirements for RACM/RACT**  CAA section 172(c)(1) requires that each attainm ent plan “provide for the implementation of all RACM as expeditiously as practicable, i ncluding such reductions in emissions from the existing sources in the area as may be obtained through the adoption, at a minimum , of RACT , and shall provide for attainm ent of the national primary ambient air quality standards.” EPA interprets RACM including RACT under section 172 as measures that a state finds are both reasonably

available and contribute to attainment as expeditiously are practicable in the nonattainment area. Thus, what constitutes RACM or RACT in a PM 2.5 nonattainment area is closely

tied to the expeditious attainment demonstration of the plan ( 40 CFR 51.1010; 72 FR 20586 at 20612 )

. States are required to evaluate RACM/RACT for direct PM 2.5 emissi ons and all of the area’ s attainment plan precursors ( 40 CFR 51.1002(c); 72 FR 20586 at 20589

– 97 ). Consistent with the guidance provided for the PM 2.5 Implementation Rule, a state initially must evaluate RACM/RACT for sources that emit direct PM 2.5 , SO 2 , and NOx. A state may establish with an appropriate demonstration that it should not regulate NOx in the specific nonattainment area, so it could thereby

forgo evaluation of RACM/RACT for NOx. Because EP A concluded that VOC and NH 3 are presumptively not regulatory

precursors for PM 2.5 , unless the state or EPA determines that it is necessary to regulate them in a specific nonattainment area, the state is not required to evaluate RACM/RA CT for sources of VOC or NH 3 unless there is a determination supported by

an appropriate demonstration that such emissions need to be regulated for expeditious attainment of the NAAQS in the specific area. For PM 2.5 attainment plans, the PM 2.5 Implementation Rule requires a combined approach to RACM and RACT under subpart 1 of p art D of the CAA. Subpart 1, unlike subparts 2 and 4, does not identify

specific source categories for which EPA must issue control technique documents or guidelines, or identify specific source categories for state and EPA evaluation18

during attainme nt plan development ( 72 FR 20586 at 20610 ) . Rather, under subpart 1, EPA considers RACT to be part of an area’s overall RACM obligation consistent with the section 172 definition. Because of the variable nature of the PM 2.5 problem in different nonattainment areas which may

require states to develop attainment plans that address widely disparate circumstances, EPA determined not only that states should have flexibility with respect to RACM/RACT controls but also that in areas needing significant emission reductions, RACM/RACT controls on smaller sources may be necessary

to reach attainment as expeditiously as practicable ( 72 FR 20586 at 20612, 20615 ) . Thus, under the PM 2.5 Implementation Rule, RACM and RACT are those reasonably available measures that contribute to attainment as expeditiously

as practicable in the specific nonattainment area ( 40 CFR 51.1010; 72 FR 20586 at 20612 )

. Specifically , the PM 2.5 Implementation Rule requires that attainment plans include the list of measures that a state considere d and information sufficient to show that the state met all requirements for the determination of what constitutes RACM/RACT in a specific nonattainment area ( 40 CFR 51.1010(a) ) . In addition, the PM 2.5 Implementation Rule requires that the state, in deter mining whether a particular emissions reduction measure or set of measures must be adopted as RACM/RACT, consider the cumulative impact of implementing the available measures and to adopt as RACM/RACT any potential measures that are reasonably available co nsidering technological and economic feasibility if, considered collectively , they would advance the attainment date by one year or more. I f a measure or measures is not necessary for expeditious attainment of the NAAQS in the area, then by definition that measure is not RACM/RACT for purposes of the 1997 PM 2.5 NAAQS in that area. Any measures that are necessary to meet these requirement s which are not already either F ederally

promulgated, part of the state’s SI P, or otherwise creditable in SI Ps must be s ubmitted in enforceable form as part of a state’s attainment plan for the area ( 72 FR 20586 at 20614 )

. Guidance provided in the PM 2.5 Implementation Rule for evaluating RACM/RACT level controls for an area also indicated that there could be flexibility with respect to those areas that were predicted to attain the 1997 PM 2.5 NAAQS within five years of designation as a result of existing national or local measures ( 72 FR 20586 at 20612 ) . In such circumstances, EPA indicated that the state may conduct a mo re limited RACM/RACT analy sis that does not involve additional air quality

modeling. Moreover, the RACM/RACT analy sis for such area would focus on a review of reasonably available measures, the estimation of potential emissions reductions, and the evaluat ion of the time needed to implement the measures. Thus, the PM 2.5 Implementation Rule guidance recommended that not all areas would need to conduct as rigorous an analy sis, and suggested that a less rigorous analy sis would be needed for those areas expect ed to attain within the initial five y ears from designation as a nonattainment area for the 1997 PM 2.5 NAAQS. A more comprehensive discussion of the RACM/RACT requirement for PM 2.5 attainment plans and EPA’s guidance for it can be found in the PM 2.5 Imple mentation Rule preamble ( 72 FR 20586 at 20609

– 20633 )

.19

**2 .**  **Delaware ’s Analysis of Pollutants and Sources**  **Delaware Portion of the Philadelphia**  **Area.** Based upon the emissions inventory for the area, Delaware determined that it would be appropriate to eva luate sources of PM 2.5 , SO 2 , and NOx located in the nonattainment area for potential control as RACM/RACT. Delaware did not determine that controls of sources of VOC or NH 3 would be necessary for expeditious attainment of the NAAQS in this area, nor does EPA believe that there is a need to do so. Delaware ’s determination with respect to which pollutants the plan should evaluate is at section 1.4 of the attainment plan submittal. After evaluating which pollutants should be ad dressed in the attainment plan, Delaware identified all source categories of those emissions located within the nonattainment area to determine available controls that could bring the area into attainment as expeditiously as possible ( section 7 of the attainment plan submittal )

. For the primary PM 2.5 RACM, DNREC evaluated measures that are limited to the boundaries of the nonattainment area, i.e. New Castle County

. However, because SO 2 and NOx can be transported over considerable distances to form PM 2.5 , they were assessed on a state wide basis ( Appendix 7

- 1 of Delaware’s attainment plan for “EPA’s Li st of Potential Control Measures” ). Although VOC is not a regulated PM 2.5 precursor for the Delaware portion of the Philadelphia area, VOC control measures approved by EPA were included i n the modeling associated with this attainment plan. Inaccordance with 40 CFR 51.1010, a SI P revision for a PM 2.5 nonattainment area is required to demonstrate that all RACM, including RACT stationary sources necessary

to demonstrate attainment as exped itiously as practicable have been adopted. The cumulative impact of implementing available measures must be considered in determining whether a particular emission reduction measure or set of measures is required to be adopted as RACM. Potential measures that are reasonably available considering technical and economic feasibility must be adopted as RACM if, considered collectively , they would advance the attainment date by one year or more. Since the Delaware portion of the Philadelphia area attained at the end of 2009, any RACM measures need to be in effect in 2008. Delaware determined that there are no additional control measures that could be adopted by January 1, 2008. In addition, existing measures and measures planned for implementation by 2009 en abled the Delaware portion of the Philadelphia area to attain the 1997 PM 2.5 NAAQS. Therefore, no further actions on RACM or RACT are warranted.
**3 .**  **Delaware ’s evaluation of RACM/RACT control measures for the**  **Delaware Portion of**  **the Philadelphia Area.** Inaccordance with section 172 of the CAA, the Delaware portion of the Philadelphia area has adopted all RACM, including RACT, needed to attain the standards “as expeditiously as practicable.” Delaware ’s demonstration for attaining the 1997 annual PM 2.5 N AAQS in the Delaware portion of the Philadelphia area is based on enforceable measures.20

**a. STATIONARY POINT SOURCES** 

- Consent Decree, Premcor Refinery in New Castle County

– control of SO 2 and NOx emissions from boilers and heaters

- Regulation 1146

– Electric Generating Unit Multi

- Pollutant Regulati on
– S O 2 and NOx emission control

- Regulation 1148

– Control of Stationary Combustion Turbine Electric Generating Unit Emissions

– NOx emission control

- Regulation 1144

– Control of Stationary Generator Emissions

– SO 2 , PM, VOC and NOx emission control

- Regulation 1142

– Section 1

– Control of NOx Emissions from Industrial Boilers

- Regulation 1142

– Section 2

– Control of NOx Emissions from Industrial Boilers and Process Heaters at Petroleum Refineries in New Castle County

- Regulation 24

– Section 46

– Crude Oil L ightering Operations

– VOC emission control

- Facility

and unit shutdowns
**b. AREA SOURCES** 

- Regulation 24

– Section 33

– Solvent Cleaning and Drying, VOC emission control

- Regulation 24

– Section 11

– Mobile Equipment Repair and Refinishing, VOC emission control

- Regulation 41

– Section 3

– Portable Fuel Containers , VOC emission control

- Regulation 41

– Section 3

– Consumer Products, VOC emission control

- Regulation 41

– Section 1

– Architectural and Industrial Maintenance Coatings, VOC emission control

- Regulation 24

– Section 36

– Stage I I Vapor Recovery , VOC emission control

- Residential Woodstoves , 40 CFR Part 60 Subpart AAA

– New Source Performance Standards (NSPS) for PM, VOC and NOx emission control21

- Regul ation 1113

– Open Burning

– PM, VOC and NOx control

**c. HIGHWAY VEHICLES** 

- Regulation 31

– Lo w Enhanced inspection and Maintenance Program

- Regulation 1132

– Transportation Conformity Regulation

- 40 CFR Parts 80, 85 and 86

– Control of Air Pollution from New Motor Vehicles

– Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control Requirements

- 40 CFR Parts 69, 85 and 86

– Control of Air Pollution from New Motor Vehicles

– Heavy
- Duty

Engines and Vehicle Standards and Highway Diesel Fuel Sulfur Con trol Requirements

- Regulation 1145

– Excessive I dling of Heavy Duty Vehicles

- Regulation 40

– National L ow Emission Vehicle (NLEV ) Program
**d. NONROAD SOURCES** 

- Phase Iand Phase I I Emissions Standards for Gasoline

- Powered Nonroad Utility Engines, Federal Ru le

- Emissions Standards for Diesel

- Powered Nonroad Utility Engines of 50 or More Horsepower , Federal Rule

- Emissions Standards for Spark I gnition (SI ) Marine Engines, Federal Rule

- Emissions Standards for L arge Spark I gnition Engines, Federal Rule

- Reformu lated Gasoline Use in Nonroad Motor Vehicles and Equipment, Federal Rule

**e. OTHER MEASURES** 

- Regulation 1124

– Section 36

– Mandatory episodic prohibition of lightering on ozone action day s

- Regulations 1146 and 1148

– Reduction of emissions from high electr ic demand day electric generations22

- Voluntary

measures effective in 2010 include: Brandy wine School District bus retrofits; Delaware ride share; ozone action day s; use biodiesel in state

- run equipment; best workplaces for commuters and SmartWay transp ort programs; implement an anti

- idling outreach programs for school and school districts; clean state program; installation of E85 station; and continue to identify and implement efficiency programs for the residential and commercial sectors.
**4 . RAC**  **M/RACT Demonstration and Control Strategy** Delaware ’s evaluation of RACM/RACT control measures for the Delaware portion of the Philadelphia area is approvable. Th e most current monitoring data for this area indicates that it is attaining the 1997 PM 2.5 NA AQS. EPA’s guidance for the PM 2.5 Implementation Rule recommended that if an area was predicted through the attainment plan to attain the standards within five years after designation, then the s tate could submit a more limited RACM/RACT analy sis and the s tate could elect not to do additional modeling. Inlight of the fact that the Delaware portion of the Philadelphia area is now attaining the standards, the attainment plan meets the RACM/RACT requirements of the PM 2.5 Implementation Rule, and that the level of control in Delaware ’s attainment plan constitutes RACM/RACT for purposes of the 1997 PM 2.5 NAAQS. Because the PM 2.5 Implementation Rule defines RACM/RACT as that level of control that is necessary to bring the area into attainment, the current le vel of federally enforceable controls on sources located within the Philadelphia area is by definition RACM/RACT for this area for this purpose.
**V . Reasonable Further Progress**  Section 172(c)(2) of the CAA requires that attainment plans include RFP to achieve steady progress toward meeting air quality standards by

showing generally

linear p rogress t oward attainment. The PM 2.5 Implementation Rule set forth that an area that demonstrates attainment by 2010 will be considered to have satisfied the RFP req uirement and need not submit any additional material to satisfy the RFP requirement. EPA views the attainment demonstration as also demonstrating that the area is making reasonable further progress toward attainment. A s tate is required to submit a separ ate RFP p lan for any area for which the s tate seeks an extension of the attainment date beyond 2010. The RFP plan is required to provide emission reductions such that emissions in 2009 represent generally linear progress from the 2002 baseline ye ar to the attainment year. The Delaware portion of the Philadelphia area attained by 2010, and has therefore met the RFP requirements. For similar reasons, such areas are not subject to a requirement for a mid

- course review.23

**V I**  **. Contingency Measures**  Inaccordance with section 172(c)(9) of the CAA, the PM 2.5 Implementation R ule requires that PM 2.5 attainment demonstrations include contingency measures ( 40 CF R 51.1012 and 72 FR at 20642

– 20646 , April 25, 2007 ) . Contingency measures are additional measures to be implemented in the event that an area fails to meet RFP or fails to attain a standard by its attainment date. These measures must be fully adopted rules or control measures that can be implemented quickly

and without significant further EPA or state acti on if the area fails to meet RFP or fails to attain by

its attainment date, and should contain trigge r mechanisms and an implementation schedule. In addition, they should be measures not already included in the SI P control strategy

and should provide for emission reductions equivalent to one year of RFP
. Delaware submitted contingency measures as required by

the PM 2.5 Implementation Rule, composed of: electric generating unit multi

- pollutant regulation controlling NOx and SO 2 emissions; and a consent decree with Premcor Refinery controlling NOx emissions from boilers and heaters. In accordance with section 110(k)(2) of the CAA, EPA must take action on the contingency

measures that were submitted by Delaware. However, as noted in section A.I II. of th is document , the Delaware portion of the Philadelphia area, which consists of New Castle County , has attained the 1997 annual PM 2.5 NAAQS, meets the attainment date of April 5, 2010, and continues to attain based on the most recent data available. Because EPA has determined that the area attained by

its required attainment date, in accordance with section 179(c)( 9 ), no contingency

measures for failure to attain by this date need be implemented, and further EPA action is unnecessary . Furthermore, as set fo rth in the PM 2.5 Implementation Rule, areas that attained the NAAQS by

the attainment date are considered to have satisfied the requirement to show RFP, and as such do not need to implement contingency measures to make further progress to attainment. EPA has determined that the area has attained by the attainment date, therefore the contingency

measures submitted by

Delaware are no longer necessary for the Delaware portion of the Philadelphia area to meet RFP requirements or attain the annual PM 2.5 NAAQS b y the attainment date. The PM 2.5 Implementation Rule requires that quantity of emission reductions needed to satisfy contingency

requirements is an amount equal to one’s year worth of required reductions. Required reductions are the amount of reductions needed to attain compliance with the PM 2.5 NAAQS
. 2002 emissions are the base year emissions and the CMAQ modeled 2009 emissions are the emission levels necessary for attainment. Therefore, the difference between these emission levels is the total quantity of reductions required for attainment. Since there are seven ye ars between 2002 and 2009, the total quantity of reductions required for attainment is divided by seven to determine one

- ye ar’s worth of required reductions (i.e., the contingency requirement). Table 9 display s the 2002 base year emissions and the 2009 emission reductions (i.e., attainment t argets ) accounted for in the CMAQ model which showed attainment in 2010 for the Philadelphia area.24

**Table 9**  **. 2002 Base Year and CMAQ Modeled 2009 Emiss**  **ions (**  **tpy )**  Year County NOx PM 2.5 SO 2 2002 New Castle 30748 3430 50237 2009 New Castle 23048 3249 12001
Table 10 shows one y ear’s worth of required emission reductions (i.e., the amount require for contingency

). This was calculated by subtracting the attainment targets from the 2002 base ye ar and dividing the difference by 7 y ears. **Table 10**  **. Contingency Requirement (t**  **py )**  County NOx PM 2.5 SO 2 New Castle 1100 26 5462
Table 11 shows that Delaware has me t the contingency requirements relative to the pollutants NOx and PM 2. 5 , since the projected 2009 emission levels are lower than those needed for attainment by

at least the amount of the contingency requirement. **Table 11**  **. Calculation of Required Contingency Plan Reductions**

New Castle County NOx (t py ) PM 2.5 (t

py ) Target Reductions for Attainment 23048 3249 Calculated Excess Reductions 1241 234 Contingency

Requirement 1100 26 Excess Reductions Satisfy Contingency Requirement Yes Yes

**VI II**  **. Motor Vehicle Emission Budgets**  Section 176(c ) of the CAA requires Federal actions in nonattainment and maintenance areas to “conform to” the g oals of SI Ps. This means that such actions will not c ause or contribute to violations of a NAAQS , worsen the severity of an existing violation , or delay time ly attainment of any NAAQS or any interim milestone

. Actions involving Federal Highway Administration (FHWA) or Federal Transit A dministration (FTA) funding or approval are subject to the transportation conformity rule (40 CFR 93, subpart A). Under this rule, metropolitan p lanning organizations (MPOs) in nonattainment and maintenance areas coordinate with S tate A ir Q uality

and T ransportation A gencies, EPA, and the FHWA and FTA to demonstrate that their long range transportation plans ( “plans”) and transpo rtation improvement programs (T IP ) conform to applicable SI Ps. This is ty pically determined by

showing that estimated emissions from existing and planned highway and transit projects are less than or equal to the MVEBs contained in the SI P.25

The MVEBs for the 2009 attainment year are based on the projected 2009 onroad motor vehicle source emissions, accounting for the emission reductions from on

- road vehicle sourc e control measures , including transportation control measures and vehicle technology , fuel or m aintenance

- based measures. MVEBs for 2009 attainment year for the Delaware portion of the Philadelphia area , submitted on April 3. 2008 were 87 t py for PM 2.5 - direct and 4,904 t py for NOx
. More detailed information can be found in the TSD entitled, “Adequ acy Findings for Motor Vehicle Emissions Budgets in the 2009 Attainment Plan for the Delaware Portion of the Philadelphia 1997 PM 2.5 NAAQS Nonattainment Area, ” January 7, 2010
. The budgets that Delaware submitted on April 3, 2008 were calculated using the MOBI LE6.2 motor vehicle emissions model because this model was the most current model available at the time Delaware was performi ng its analy sis. EPA has issued an updated motor vehicle emissions model known as the Motor Vehicle Emission Simulator or M OVES. In its announcement of this model, EPA established a grace period for continued use of MOBILE6.2 in transportation conformity determinations for transportation plans and TIPs, after which states and MPOs (other than California) must use MOVES for tr ansportation plan and TI P conformity determinations. This grace period will expire in March 2012 ( or March 2013 once the extension becomes official ). Additional information on the use of MOVES in SI Ps and conformity determinations can be found in the De cember 2009 , “ Policy Guidance on the Use of MOVES2010 for State Implementation Plan Development, Transportation Conformity , and Other Purposes

. ” This guidance document is available at: http ://www.epa.gov/otaq/models/moves/420b09046.pdf

. During the conformity

grace period, the s tate and MPO(s) should use the interagency consultation process to examine how MOVES2010 will impact their future transportation plan and TI P conformity

determination s, including regional emissions analy ses. For example, an increase in emission estimates due to the use of MOVES2010 may affect an area’s ability

to demonstrate conformity

for its transportation plan and/or TI P. Therefore, state and local planners should carefully

consider whether the SI P and motor vehicle emissions budget(s) should be revised with MOVES2010 or if transportation plans and TI Ps should be revised before the end of the conformity

grace period, since doing so may be necessary

to ensure confor

mity determinations in the future. We would expect that states and MPOs would work closely with EPA and the local FHWA and FTA offices to determine an appropriate course of action to address this ty pe of situation if it is expected to occur. I f Delaware chooses to revise its PM 2.5 attainment plan , it should consult Question 7 of the December 2009 , “ Policy Guidance on the Use of MOVES2010 for State Implementation Plan Development, Transportation Conformity , and Other Purposes ,” for information on requireme nts related to such revisions. On November 17, 2011 , DNREC submitted a SI P revision that is related to the PM 2.5 and NOx onroad mobile source budgets that were established in the April 3, 2008 submittal. The budgets in the April 3, 2008 submittal were es tablished using EPA’s MOBI LE6.2 model.26

However, effective March 2012 (or March 2013 once the extension becomes official), the MOVES model is required to be used in all planning and transportation conformity determinations. The purpose of th e supplemental SI P revision submitted on November 17, 2011 , is to 1) replace the onroad emissions budget in the April 3, 2008 submittal with a budget that is based on the MOVES model ; 2) demonstrate that the MOVES based mobile source budget is consistent with attainment of the PM 2.5 NAAQS by 2010 ; and 3) demonstrate that the contingency

requirements of the CAA are met. This SI P revision only impacts PM 2.5 and NOx emissions and calculations. More detailed information can be found in the TSD entitled, “Adequacy

Finding s for Motor Vehicle Emissions Budgets in the Attainment Demonstration for the Delaware Portion of the Philadelphia

- Wilmington

- New Jersey 1997 PM 2.5 NAAQS Nonattainment Area,” January 11, 2012. EPA MOVES model was used to quantify PM 2.5 and NOx emission from onroad mobile sources. The emission levels for the onroad mobile emissions budget for New Castle County are shown in Table 12
. See Appendix A of the November 17, 2011 submittal for the associated 2012 MOVES input and output files. **Table 12**  **. Revise**  **d Onroad Mobile Emission Budget (t**  **py )** 

**County Emissions Budget**  New Castle NOx PM 2.5 6273 199
Delaware demonstrated attainment of the annual PM 2.5 NAAQS in its April 3, 2008 submittal by

showing that the projected 2009 emissions (i.e. the 2009 emission levels after the implementation of all state and Federal control requirements) were less than the attainment targets (i.e. the emissions levels needed for attainment based on modeling). The same methodology

is used to demonstrate that the MOVES based mob ile budgets are consistent with attainment of the PM 2.5 NAAQS. See Appendix B of the November 17, 2011 submittal for the associated 2009 MOBI LE6.2 and MOVES input and output files. CMAQ modeling was conducted in the April 3, 2008 submittal to demonstrate that Delaware and the entire Philadelphia area would attain the PM 2.5 NAAQS in 2010 (attainment date). See s ection 6 of the April 3, 2008 submittal. CMAQ modeling demonstrated that the Delaware emission levels, referred to as attainment target, shown in Table 13 are consistent with attainment of the annual PM 2.5 NAAQS. **Table 13**  **. 2009**  **Attainment Target (t py**  **)**

**County NOx**  **PM 2.5**  Kent 8554 1185 New Castle 23048 3249 Sussex 18001 3581 Statewide Total 49603 801527

Attainment y ear (i.e. 2009) emission lev els were projected in the April 3, 2008 submittal based on the final and enforceable state and Federal emission requirements. These projected 2009 emission levels, referred to as projected 2009 emissions are shown in Table 14
. **Table 14**  **. Projected 2009 E missions (**  **tpy )** 

**County NOx**  **PM 2.5**  Kent 7799 989 New Castle 21807 3015 Sussex 11591 2571 Statewide Total 41197 6575
Table 1 5 compares the 2009 mobile emissions calculated using MOBI LE6.2 and MOVES. See Appendix B of the submittal for the associat ed 2009 MOBI LE6.2 and MOVES input and output files. **Table 1 5**  **. 2009 MOBILE6.2 and MOVES (tpy)** 

**2009 MOBILE6.2 2009 MOVES**  **MOVES Increase County**  **NOx PM**  **2.5 NOx**  **PM 2.5**  **NOx PM**  **2.5** Kent 1922 32 3488 109 1566 77 New Castle 4904 87 8448 257 3544 170 S ussex 2707 41 4764 147 2057 106 Totals 9533 160 16700 513 7167 353
Table 1 6 reflects the revised projected 2009 emissions using the MOVES model instead of MOBI LE6.2, i.e. adding the MOVES increase and the projected 2009 emissions. **Table 1 6**  **. Revise d Projected 2009 Emissions (**  **tpy )** 

**County NOx**  **PM 2.5**  Kent 9365 1066 New Castle 25351 3185 Sussex 13648 2677 Statewide Total 48364 6928 The revised projected 2009 emissions are demonstrated to be consistent with attainment if they are equal or lower than the 2009 attainment target. The revised projected 2009 emissions are compared to the attainment target in Table 1 7 . This comparison shows that there is a surplus of 64 tons per year PM 2.5 in New Castle County

. This demonstrates that relative to dire ct PM 2.5 , the MOVES based mobile budgets are consistent with attainment.28

**Table 1 7**  **. Shortfall and Surplus by County and Statewide ( tpy**  **)**

**Attainment Target Revised Projected**  **2009 Emissions Surplus/Shortfall**  **County NOx**  **PM 2.5**  **NOx PM**  **2.5 NOx**  **PM 2.5**  Kent 85 54 1185 9365 1066
- 811 119 New Castle 23048 3249 24351 3185
- 2303 64 Sussex 18001 3581 13648 2677 4353 904 Statewide 49603 8015 48364 6928 1239 1087
Inaddition, since 64 t

py PM 2.5 emissions show that it is greater than the contingency requirement of 26 t

py , the contingency

requirement is demonstrated relative to PM 2.5 . See s ection 9 of the April 3, 2008 submittal for the contingency requirements. Because of the regional nature of secondarily

- formed sulfate and nitrate, and the broad mod e ling domain of the CMAQ modeling, which included all of Delaware, em ission reductions from Kent and Sussex counties , will contribute to attainment within New Cas tle County and the Philadelphia area. Kent and Sussex C ounties are within the State of Delaware, contiguous to New Castle County , and are less than 200 kilometers away . EPA’s PM 2.5 Implementation Rule specifically

provides for the consideration of in

- state NO X and SO 2 reductions in their SI Ps from sources up to 200 kilometers away from the non

- attainment area boundaries

. See PM 2.5 Implementation Rule, 72 FR 20586 at 20636. While there is a 2009 NOx shortfall in New Castle County , there is a statewide NOx surplus of 1,239 tpy . Therefore, the 2009 MOVES based emissions do not impair Delaware’s ab ility to meet the PM 2.5 NAAQS. Inaddition, since the 2009 NOx emissions of 1,239 tpy show that it is greater than the contingency

requirement of 1,100 t

py NOx , the contingency

requirement is demonstrated relative to NOx
. See s ection 9 of the April 3, 2008 submittal for the contingency requirements. For MVEBs to be approvable, they must meet, at a minimum, EPA’s adequacy criteria (40 CFR 93.118(e)(4)). The MVEBs for the Delaware portion of the Philadelphia area PM 2.5 attainment plan are being posted t o EPA’s conformity website concurrently

with the notice of proposed rulemaking (NPR). The public comment period will end at the same time as the public comment period for the NPR. In this case, EPA is concurrently processing the action on the attainment plan and the adequacy process for the MVEBs contained therein. In the NPR, EPA is proposing to find the MVEBs adequate, and also proposing to approve the MVEBs as part of the attainment plan. The MVEBs cannot be used for transportation conformity until the attainment plan and associated MVEBs are approved in a final Federal Register notice, or EPA otherwise finds the budgets adequate in a separate actio n following the comment period. Our action on the Delaware portion of the Philadelphia area MVEBs will also be announced on EPA’s conformity website: http://www.epa.gov/otaq/state resources/transconf/index.htm , (once there, click on “Adequacy

Review of SI P Submissions).29

**D .**  **SUMMARY AND RECOMMENDATIONS :**  The PM 2.5 attainment plan for the Delaware portion of the Philadelphia area meets the requirements of the CAA as described in the Clean Air Fine Particle Implementation Rule (April 25, 2007, 72 FR 20586). The attainment plan supports a determination that the Delaware portion of the Philadelphi a area attains the 1997 annual PM 2.5 NAAQS
. The attainment plan includes an attainment demonstration, MVEBs used for transportation conformity purposes, RACM /RACT analy sis, contingency

measures, and the 2002 base year emission inventor ies

. Therefore, we recommend approval of the PM 2.5 attainment plan for the Delaware portion of the Philade lphia area.