C.Mail:EPA-R03-OAR-2010-0141, Donna Mastro, Acting Associate Director, Office of Air Planning Program, Mailcode 3AP30, U.S. Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103.
D.Hand Delivery:At the previously-listed EPA Region III address. Such deliveries are only accepted during the Docket's normal hours of operation, and special arrangements should be made for deliveries of boxed information.
Throughout this document, whenever “we,” “us,” or “our” is used, we mean EPA. The following is provided to aid in locating information in this preamble.
I. Summary of Action
A. Designation History
B. Clean Air Fine Particle Implementation Rule
C. Determinations of Attainment
III. Description of the Delaware Attainment Plan
IV. EPA's Analysis
A. Attainment Demonstration
1. Pollutants Addressed
2. Emission Inventory Requirements
4. Reasonably Available Control Measures/Reasonably Available Control Technology
5. Reasonable Further Progress
6. Contingency Measures
7. Attainment Date
B. Motor Vehicle Emissions Budgets (MVEBs)
V. Proposed Action
VI. Statutory and Executive Order Reviews
I. Summary of Action
EPA is proposing to approve Delaware's SIP revision which was submitted by the State of Delaware through the Delaware Department of Natural Resources and Environmental Control (DNREC) to EPA on April 3, 2008, as amended on April 25, 2012, which demonstrates attainment of the 1997 annual PM2.5NAAQS for the Philadelphia Area. This PM2.5attainment plan includes Delaware's attainment demonstration and MVEBs used for transportation conformity purposes for New Castle County in Delaware. The April 25, 2012 SIP revision submittal (1) replaced 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) demonstrated that the MOVES based mobile source budget is consistent with attainment of the PM2.5NAAQS by 2010; and (3) demonstrated that the contingency requirements of the CAA are met. The April 25, 2012 submittal only impacts PM2.5and nitrogen oxide (NOX) emissions and calculations.
The attainment plan also includes a base year emissions inventory, an analysis of RACM/RACT, and contingency measures. EPA has determined that a RFP plan is not required because Delaware demonstrated that attainment with the 1997 annual PM2.5NAAQS occurred in the Philadelphia Area by the attainment date of April 2010.
In a separate and concurrent process, EPA is conducting a process to find adequate the MVEBs for New Castle County which are associated with the Delaware attainment demonstration for the Philadelphia Area. Concurrently with EPA's proposal to approve the SIP, a notice will be posted on EPA's Web site athttp://www.epa.gov/otaq/stateresources/transconf/currsips.htmfor the purpose of opening a 30-day public comment period on the adequacy of the MVEBs for New Castle County in the April 25, 2012 SIP revision's attainment demonstration for the Philadelphia Area. That notice will inform the public of the availability of the Delaware SIP revision on DNREC's Web site. Interested members of the public could access Delaware's April 25, 2012 SIP revision on line atwww.regulations.gov,Docket No. EPA-R03-OAR-2010-0141. Following EPA's public comment period, responses to any comments received will be addressed. EPA has reviewed the revised MVEBs developed with MOVES and found them consistent with the attainment demonstration and found that the budgets meet the criteria for adequacy and approval.
EPA has determined that Delaware's PM2.5attainment plan meets the applicable requirements of the CAA, as described in the PM2.5Implementation Rule published on April 25, 2007 (72 FR 20586). EPA's analysis and findings are discussed in this proposed rulemaking. In addition, technical support documents (TSDs) for this proposal are available on line atwww.regulations.gov,Docket No. EPA-R03-OAR-2010-0141. These TSDs provide additional explanation of EPA's analysis supporting this proposal.
A. Designation History
On July 16, 1997, EPA established the 1997 PM2.5NAAQS, including an annual standard of 15.0 micrograms per cubic meter (µg/m3) based on a 3-year average of annual mean PM2.5concentrations and a 24-hour (or daily) standard of 65 µg/m3based on a 3-year average of the 98th percentile of 24-hour concentrations.See62 FR 38652 (July 18, 1997). EPA established these standards based on significant evidence and numerous health studies demonstrating that serious health effects are associated with exposures to PM2.5.
Following promulgation of a new or revised NAAQS, EPA is required by the CAA to designate areas throughout the United States as attaining or not attaining the NAAQS; this designation process is described in section 107(d)(1) of the CAA. In 1999, EPA and state air quality agencies initiated the monitoring process for the 1997 PM2.5NAAQS and by January 2001, established a complete set of air quality monitors. On January 5, 2005 (70 FR 944), EPA promulgated initial air quality designations for the 1997 PM2.5NAAQS, which became effective on April 5, 2005, based on air quality monitoring data for calendar years 2001-2003.
On April 14, 2005 (70 FR 19844), EPA promulgated a supplemental rule amending EPA's initial designations, with the same effective date (April 5, 2005) as 70 FR 944. As a result of this supplemental rule, PM2.5nonattainment designations are in effect for 39 areas, comprising 208 counties within 20 states (and the District of Columbia) nationwide, with a combined population of about 88 million. The Philadelphia Area which includes New Castle County in Delaware is in the list of areas not attaining the 1997 annual PM2.5NAAQS.
It should 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-hour PM2.5NAAQS. The designation for New Castle County was clarified as unclassifiable/attainment for the 1997 24-hour PM2.5NAAQS.
B. Clean Air Fine Particle Implementation Rule
The PM2.5Implementation Rule describes the CAA framework and requirements for developing SIPs for areas designated nonattainment for the 1997 PM2.5NAAQS. An attainment plan must include a demonstration that a nonattainment area will meet the applicable NAAQS within thetimeframe 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). It must also include supporting technical analyses and descriptions of all relevant adopted Federal, state, and local regulations and control measures that have been adopted in order to provide attainment of the 1997 PM2.5NAAQS by the proposed attainment date.
For the 1997 PM2.5NAAQS, an attainment plan must show that a nonattainment area will attain the 1997 PM2.5NAAQS 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). If the area is not expected to meet the NAAQS by April 2010, a state may request to extend 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 each nonattainment area, the state must demonstrate that it has adopted all RACM, including all RACT for the appropriate emissions sources, needed to provide for attainment of the PM2.5standards in the specific nonattainment area “as expeditiously as practicable.” The PM2.5Implementation Rule provided guidance for making these RACM/RACT determinations (seesection IV.A.4 of this notice). Any measures that are necessary to meet these requirements that are not already Federally promulgated or in an EPA-approved part of the state's SIP must be submitted as part of a state's attainment plan. Any state measures must meet the applicable statutory and regulatory requirements, and in particular, must be enforceable.
The PM2.5Implementation Rule also included guidance on pollutants that states must address in their attainment plans. Section 302(g) of the CAA authorizes EPA to regulate criteria pollutants and their precursors. In the case of PM2.5, the main chemical precursors are sulfur dioxide (SO2), NOX, ammonia (NH3), and volatile organic compounds (VOCs). The effect of reducing emissions of precursor pollutants that contribute to PM2.5concentrations varies by area, however, depending on PM2.5composition, emission levels, and other area-specific factors. For this reason, the PM2.5Implementation Rule provided guidance recommending that states elect to control direct PM2.5emissions and the precursor or precursors that would be most effective for attaining the NAAQS within the specific area, based upon an appropriate technical demonstration.
In accordance with the PM2.5Implementation Rule, direct PM2.5emissions 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 particulate matter at ambient temperatures. Direct PM2.5emissions include elemental carbon, directly emitted organic carbon (OC), directly emitted sulfate (SO4), directly emitted nitrate (NO3), and other inorganic particles (including but not limited to crustal material, metals, and sea salt).”
The PM2.5Implementation Rule requires all states to address SO2as a PM2.5precursor and to evaluate SO2for possible control measures in all PM2.5nonattainment areas. States are required to address NOXas a PM2.5precursor and evaluate reasonable controls for NOXin all PM2.5attainment plans, unless the state and EPA make a finding that NOXemissions from sources in the state do not significantly contribute to PM2.5concentrations 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 organic material in the formation of organic particulate matter (PM), this relationship remains complex. Further research and technical tools are needed to better characterize emissions inventories for specific VOC compounds and to determine the extent of the contribution of specific VOC compounds to organic PM mass. Because of these factors, the PM2.5Implementation Rule did not require states to address VOCs as PM2.5attainment plan precursors and evaluate them for control measures, unless the state or EPA made a finding that VOCs significantly contribute to a PM2.5nonattainment problem in the specific area or to other downwind air quality concerns.
The PM2.5Implementation Rule also describes the formation of particles related to NH3emissions, which is a complex, nonlinear process. Though recent studies have improved our understanding of the role of NH3in aerosol formation, ongoing research is needed to better describe the relationships between NH3emissions, PM concentrations, and related impacts. Also, area-specific data is needed to evaluate the effectiveness of reducing NH3emissions on reducing PM2.5concentrations in different areas, and to determine where NH3decreases may increase the acidity of particles and precipitation. For these reasons, in the PM2.5Implementation Rule, NH3is presumed not to be a PM2.5attainment plan precursor, meaning that the state is not required to address NH3in its attainment plan or evaluate sources of NH3emissions for reduction measures, unless the state or EPA makes a finding that NH3significantly contributes to a PM2.5nonattainment problem in the area or to other downwind air quality concerns.
The presumptive inclusion of NOXand the presumptive exclusion of VOC and NH3as precursors can be reversed based on an acceptable technical demonstration for a particular nonattainment area by the state or EPA. Such a demonstration should include information from multiple sources, including results of speciation data analyses, air quality modeling studies, chemical tracer studies, emission inventories, or special intensive measurement studies to evaluate specific atmospheric chemistry in an area.Seethe PM2.5Implementation Rule for more information.
The PM2.5Implementation Rule also provided guidance for the other elements of a state's attainment plan, including, but not limited to, emission inventories, contingency measures, and MVEBs used for transportation conformity purposes. There are, however, three aspects of the PM2.5Implementation 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 Interstate Rule (CAIR) automatically satisfies the requirements for RACT or RACM for NOXor SO2emissions from 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 consideration 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 from outside the nonattainment area to be credited as meeting the RFP requirement. EPA has granted these petitions. The Delaware attainment plan for the Philadelphia Area does not rely on any of these aspects of the rule.1
1While Delaware listed CAIR as a control measure in its discussion of RACM/RACT, Delaware's determination of RACM/RACT did not solely depend on CAIR as RACT.SeeAppendix 7-1 of Delaware's April 3, 2008 Attainment Plan.
With regard to CAIR, EPA published this rule on May 12, 2005 (70 FR 25162) to address the interstate transport requirements of the CAA with respect to the 1997 ozone and 1997 PM2.5NAAQS. As originally promulgated, CAIR required significant reductions in emissions of SO2and NOXto limit the interstate transport of these pollutants. In 2008, however, the Court of Appeals for the District of Columbia Circuit (“the Court”) remanded CAIR back to EPA.See North Carolinav.EPA,550 F.3d 1176 (D.C. Cir. 2008). The Court had previously found CAIR to be inconsistent with the requirements of the CAA,North Carolinav.EPA,531 F.3d 896 (D.C. Cir. 2008), but ultimately remanded the rule to EPA without vacatur because it found that “allowing CAIR 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 CAIR.”See North Carolinav.EPA,550 F.3d at 1178. CAIR thus remained in place following the remand, and was in place and enforceable through the April 5, 2010 attainment date.
In response to the Court's decision, EPA issued a new rule to address interstate transport of NOXand SO2in the eastern United States (i.e., the Transport Rule, also known as the Cross-State Air Pollution Rule).See76 FR 48208 (August 8, 2011). In the Transport Rule, EPA finalized regulatory changes to sunset (i.e., discontinue) CAIR and the CAIR Federal Implementation Plans (FIPs) for control periods in 2012 and beyond.See76 FR 48322.
The recent Court decision on the Transport Rule,EME Homer City Generation, L.P.v.EPA,No. 11-1302 (D.C. Cir., August 21, 2012)2
does not disturb EPA's determination that it is appropriate to move forward with this proposed action. This action proposes to approve an attainment plan that demonstrated that the Philadelphia Area would attain the 1997 annual PM2.5NAAQS by 2010, which it did, as discussed in section II.C of this notice. The air quality analysis conducted for the Transport Rule demonstrates that the Philadelphia Area would be able to attain the 1997 annual PM2.5NAAQS even in the absence of CAIR or the Transport Rule.SeeAppendix B to the Air Quality Modeling Final Rule Technical Support Document for the Transport Rule. Nothing in the D.C. Circuit's August 2012 decision disturbs or calls into question that conclusion or the validity of the air quality analysis on which it is based. More importantly, the Transport Rule is not relevant to this action. The Transport Rule only addresses emissions in 2012 and beyond. As such, neither the Transport Rule itself, nor the vacatur of the Transport Rule, is relevant to the question addressed in this proposal notice. The purpose of this action is to determine whether the attainment plan submitted by Delaware is sufficient to bring the Philadelphia Area into attainment by the April 2010 attainment date, a date before the Transport Rule was even promulgated.
2The Court's judgment is not final at this time as the mandate has not yet issued.
Similarly, the status of CAIR after the April 2010 attainment date is also not relevant to this action. While the air quality monitoring data that shows the Philadelphia Area attained the 1997 annual PM2.5NAAQS by the April 2010 attainment deadline was impacted by CAIR, CAIR was in place and enforceable through the 2010 attainment date that is relevant to this attainment plan. CAIR was an enforceable control measure applicable to affected sources in the area, as well as sources throughout the Eastern United States. As such, the current status of CAIR is irrelevant to and does not impact our conclusion that the attainment plan should be approved. Moreover, in its August 2012 decision, the Court also ordered EPA to continue implementing CAIR.See EME Homer City,slip op. at 60. For these reasons, neither the current status of CAIR nor the current status of the Transport Rule affects any of the criteria for proposed approval of this SIP revision.
C. Determinations of Attainment
EPA makes two different types of attainment determinations for nonattainment areas. The first, a Determination of Attainment by the attainment date, is a determination of whether the area attained the NAAQS as of the area's applicable attainment deadline, which, for PM2.5, is required by section 179(c) of the CAA. The second is a Determination of Attainment for purposes of suspending a state's obligation to submit certain attainment-related planning SIP requirements (i.e., the Clean Data Determinations for PM2.5).See40 CFR 51.1004(c). A Clean Data Determination and the suspension of the planning requirements continue for as long as the area continues to attain the NAAQS.
(1) Determination of Attainment by the Area's Attainment Date
In accordance with section 179(c) of the CAA, EPA determined on May 16, 2012 (77 FR 28782) that the Philadelphia Area attained the 1997 annual PM2.5NAAQS by its required attainment date of April 5, 2010. This determination was based on complete, quality-assured, quality-controlled, and certified ambient air monitoring data for 2007-2009 as well as the 2008-2010 monitoring periods.See40 CFR 51.1004(c).
(2) Clean Data Determination
On May 16, 2012 (77 FR 28782), EPA also determined that the Philadelphia Area has attained the 1997 annual PM2.5NAAQS and remains in attainment. The determination was based on complete, quality-assured, quality-controlled, and certified ambient air monitoring data for the 2007-2009 and the 2008-2010 monitoring periods.See40 CFR 51.1004(c).
III. Description of the Delaware Attainment Plan
In accordance with section 172(c) of the CAA and the PM2.5Implementation Rule, the attainment plan submitted on April 3, 2008 and amended on April 25, 2012 by DNREC for the Philadelphia Area included Delaware's attainment demonstration, MVEBs used for transportation conformity purposes for New Castle County in Delaware, a base year emissions inventory, a RACM/RACT analysis and contingency measures.
To analyze future year emissions reductions and air quality improvements, Delaware used local, regional, and national modeling analyses that have been developed to support Federal and local emission reduction programs. This modeling was performed in accordance with EPA's “Guidance on the Use of Models and Other Analyses for Determining Attainment of Air Quality Goals for Ozone, PM
and Regional Haze” (EPA-454/B-07-002, April 2007).
IV. EPA's Analysis
A. Attainment Demonstration
1. Pollutants Addressed
In accordance with policies described in the PM2.5Implementation Rule, Delaware's PM2.5attainment plan evaluates emissions of direct PM2.5, SO2, and NOXin the Philadelphia Area. With regard to evaluation of PM2.5precursors, the PM2.5Implementation Rule requires that SO2be evaluated for controls in all nonattainment areas, and describes general presumptive policies for NOX, NH3, and VOCs. For NOX, states are required to address NOXas a PM2.5attainment plan precursor and evaluate reasonable controls for NOXin PM2.5attainment plans, unless the state makesa finding that NOXemissions in the state do not significantly contribute to PM2.5concentrations in the area. For NH3, because of uncertainties regarding NH3emission inventories and the efficacy of ammonia control technologies, the final rule sets forth the presumption that NH3is not a PM2.5precursor and that states are not required to address NH3in their attainment plan. Similarly, VOC emissions are presumed not to be an attainment plan precursor because of uncertainties regarding the role of VOC in secondary organic aerosol formation. Delaware's attainment plan does not reverse any of these presumptions.
2. Emissions Inventory Requirements
States are required under section 172(c)(3) of the CAA to develop emissions inventories of point, area, onroad mobile, and nonroad mobile sources for their attainment demonstrations. These inventories provide a detailed accounting of all emissions and emission sources by precursor or pollutant. In addition, inventories are used to model air quality to demonstrate attainment of the 1997 PM2.5NAAQS 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 “Emissions 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 Consolidated 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 reporting by states. In accordance with the AERR and the November 2005 guidance, the PM2.5Implementation Rule required states to submit inventory information on directly emitted PM2.5and PM2.5precursors and any additional inventory information needed to support an attainment demonstration.
PM2.5is comprised of filterable and condensable emissions. Condensable particulate matter (CPM) can comprise a significant percentage of direct PM2.5emissions 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 PM2.5Implementation 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 PM2.5. In recognition of these concerns, EPA established a transition period during which EPA could assess possible revisions to available test methods and allow time for states to update emissions inventories as needed to address direct PM2.5, including condensable emissions. Because of the time required for this assessment, EPA recognized that states would be limited in how to effectively address CPM emissions, and established a period of transition, up to January 1, 2011, during which state attainment demonstration submissions for PM2.5were not required to address CPM emissions. Amendments to these test methods were proposed on March 25, 2009 (74 FR 12970), and finalized on December 21, 2010 (75 FR 80118). The amendments to Method 201A added a particle-sizing device for PM2.5sampling, and the amendments to Method 202 revised the sample collection and recovery procedures of the method to reduce the formation of reaction artifacts that could lead to inaccurate measurements of CPM emissions.
The period of transition for establishing emissions limits for condensable direct PM2.5ended on January 1, 2011. Attainment demonstration PM2.5submissions made during the transition period are not required to address CPM emissions; however, states must address the control of direct PM2.5emissions, including condensable emissions, with any new action taken after January 1, 2011. Delaware submitted the attainment plan prior to January 1, 2011 and therefore, did not consider condensables.
On June 25, 2007, EarthJustice filed a petition requesting reconsideration of EPA's transition period for CPM emissions provided in the PM2.5Implementation Rule. On April 25, 2011, EPA denied EarthJustice's petition for reconsideration which allowed states to continue to exclude CPM for Prevention of Significant Deterioration (PSD) permitting during the transition period. Today's action reflects a review of Delaware's submittal based on applicable EPA guidance as described in the PM2.5Implementation Rule.
The SIP base year inventory is the primary inventory from which other inventories (3-year cycle inventories, RFP inventories, modeling inventories) are derived. The CAA calls for state, local, and tribal agencies to ensure that the base year inventory is comprehensive, accurate, and current for all actual emissions (EPA-454/R-05-001). The base year inventory includes emissions estimates from stationary point and nonpoint sources, onroad mobile sources, and nonroad mobile sources. For the PM2.5NAAQS, the pollutants to be inventoried are primary emissions (including condensables3
) of PM10and PM2.5, and emissions of SO2, NH3, VOC, and NOX, and are reported as actual annual emissions. DNREC defines 2002 as the base year inventory consistent with the PM2.5Implementation Rule. The pollutants inventoried for Delaware include PM10, PM2.5, SO2, NH3, VOC, and NOX. Information on the manmade sources of direct PM and its potential precursors, SO2, NH3, VOC, and NOX, was compiled for point, area, onroad and nonroad sources.