## Responses to Significant Comments on the State and Tribal Designation Recommendations for the 2012
Annual PM 2.5 

## National Ambient Air Quality Standard (NAAQS)

Docket Number the EPA-HQ-OAR-2012-0918 U.S. Environmental Protection Agency

December 2014Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 2 of 68 

### Table of Contents

List of Acronyms .............................................................................................................. .. 3 1.0 Introduction .............................................................................................................. 5 2.0 Background .............................................................................................................. 5 3.0 Responses to Significant Comments on the State and Tribal Designation Recommendations for the 2012 annual PM 2.5 National Ambient Air Quality Standard (NAAQS) ....................................................................................................................... ..... 6 3.1 General Issues ...................................................................................................... 6 3.1.1. Data Considerations ...................................................................................... 6 3.1.2. Requests to Extend the Public Comment Period .......................................... 9 3.1.3. Other General Comments ............................................................................. 9 3.2 Area-Specific Issues ........................................................................................... 10 3.2.1. EPA Region III ........................................................................................... 10 3.2.2. EPA Region IV ........................................................................................... 22 3.2.3. EPA Region V............................................................................................. 27 3.2.4. EPA Region VI ........................................................................................... 54 3.2.5. EPA Region IX ........................................................................................... 57 3.2.6. EPA Region X............................................................................................. 58 3.2.7. Multi-Region Areas .................................................................................... 63
3.2.7.1. Louisville, KY-IN ......................................................................................... 63
3.2.7.2. Cincinnati-Hamilton, OH-KY ..................................................................... 65
3.2.7.3. St. Louis, MO-IL ......................................................................................... 67Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

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### List of Acronyms

APCD Air Pollution Control District AQS Air Quality System

CAA Clean Air Act

CBSA Core Based Statistical Areas CFR Code of Federal Regulations

CSA Combined Statistical Area

CSPAR Cross-state Air Pollution Rule DFW Dallas-Fort Worth, Texas EER Exceptional Events Rule EGU Electric Generating Unit EPA Environmental Protection Agency FR Federal Register GA EPD Georgia Environmen tal Protection Division HGB Houston-Galveston-Brazoria, Texas HYSPLIT Hybrid Single Particle La grangian Integrated Trajectory Model IEPA Illinois Environmental Protection Agency I/M (Vehicle) Inspection and Maintenance

μ g/m 3 Micrograms per cubic meter MPO Metropolitan Pl anning Organization MSA Metropolitan Statistical Area

NAA Nonattainment Area NAAQS National Ambient Air Quality Standard NEI National Emissions Inventory NFR Notice of Final Rulemaking

NLLJ Nocturnal Low Level Jet

NOAA National Oceanic and Atmospheric Administration NOx Oxides of Nitrogen

NSPS New Source Performance Standards

NSR New Source Review OAQPS EPA Office of Air Qua lity Planning and Standards OMB Office of Management and Budget

PM 2.5 Fine Particulate Matter PSD Prevention of Significant Deterioration QAPP Quality Assurance Project Plan QA/QC Quality Assurance/Quality Control RICE Reciprocating Inte rnal Combustion Engine SC DEHC South Carolina Department of Health and Environmental Control SIP State Implementation Plan

SLAMS State and Local Air Monitoring StationsResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 4 of 68 TCEQ Texas Commission on Environmental Quality TPY Tons per Year TSD Technical Support Document TVA Tennessee Valley Authority

VMT Vehicle Miles Traveled VOC Volatile Organic CompoundsResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

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### 1.0 Introduction

This document, together with the preamb le to the final rule, and the Technical Support Documents (TSDs) for the designations , presents the EPA’s responses to the significant comments we received on our pr oposed designations. The responses presented in this document are intended to augment th e responses to comments that appear in the preamble to the final rule and the TSDs or to address comments not discussed in those documents. Commenters can find TSDs in the electronic docket for this action (www.regulations.gov, docket number the EP A-HQ-OAR-2012-0918) and at the EPA’s PM Designations Web Page (http://www.epa.gov/pmdesignati ons/2012standards/index.htm).



### 2.0 Background

On December 14, 2012, the EPA promul gated a revised primary annual PM 2.5 NAAQS (78 FR 3086, January 15, 2013). In that acti on, the EPA revised the primary annual PM 2.5 standard, strengthening it from 15.0 micrograms per cubic meter ( μ g/m 3 ) to 12.0 μ g/m 3 ; retained the existing 24-hour PM 2.5 standard at 35 μ g/m 3 ; retained the existing 24-hour
PM 10 (coarse particle) standard at 150 μ g/m 3 ; and retained the current suite of secondary PM standards. The EPA revised the primary annual PM 2.5 standard based on an integrated assessment of an extensive body of new sc ientific evidence, which substantially strengthens our body of knowledge regarding PM 2.5 -related health effects. The revised primary annual PM 2.5 standard will provide increased protection for children, older adults, persons with pre-existing hear t and lung disease, and other at-risk populations against an array of PM 2.5 -related adverse health effects, in cluding premature mortality, increased hospital admissions and emergency department visits, and development and exacerbation of chronic respiratory disease.

History shows us that better health and cleaner air go hand-i n-hand with economic growth. Working closely with the states and tribes, the EPA is implementing the standard using a commonsense approach that improves air quality and minimizes the burden on state, local, and tribal govern ments. As part of this routine process, the EPA is working with the states and tribes to identify areas in the country that meet th e standard and those that need to take steps to reduce PM 2.5 air pollution. Within 1 y ear of promulgating a new or revised air quality standard, the Clean Ai r Act requires the Governor of each state to submit to the EPA a list of all areas in the state, with a design ation recommendation for each area. As a first step in implementing the 2012 annual PM 2.5 standard, Governors (and tribal leaders, if they chose) were to submit their designation recommendations, including appropriate area boundaries, by December 13, 2013.

On August 19, 2014, the EPA sent letters (the “120-day letters”) to state and tribal representatives responding to their recommendations and identifying those areas anticipated to meet the 2012 annual PM 2.5 standards and those that do not. States, tribes, and the public had the opportunity to comme nt on the EPA’s proposed decisions before the Agency issued final area designations, a nd to provide new information and analyses to the EPA, if appropriate. Following are su mmaries of significant comments received on the 2012 annual PM 2.5 designation recommendations and the EPA’s responses to those

comments.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

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### 3.0 Responses to Significant Co mments on the State and Tribal Designation Recommendations for the 2012 annual PM 2.5 

### National Ambient Air Quality Standard (NAAQS)

The following sections address the comments received by the EPA on the state and tribal
PM 2.5 designation recommendations for the 2012 annual PM 2.5 NAAQS. Comment summaries and responses are presented below.

3.1 General Issues

3.1.1. Data Considerations

Comment: Several states, including Georgia, Indiana, Ohio, and Pennsylvania, believe that data for one or more of the areas violating the 2012 annual PM 2.5 NAAQS based on 2011-2013 air quality data may show attainme nt based on 2012-2014 air quality data. Because the EPA is promulgating initial ar ea designations in December 2014, which is very close to the end of the 2014 data year, these states asked the EPA to consider 2012- 2014 data in their designation decisions, or to defer the designations process until after 2014 data are complete and state and federal regulators have an opportunity to consider areas that may have come into attain ment. One commenter noted that deferring designations to allow consider ation of 2014 data would constitute a minimal delay in the designations process and would eliminate need lessly subjecting these areas to further nonattainment requirements and burdening the states and the federal government with developing plans, redesignation requests and maintenance plans for areas that allegedly do not necessitate these activities.

EPA Response: The EPA is basing initial area designa tion decisions for most areas for the 2012 annual PM 2.5 NAAQS on air quality monito ring data for the 2011-2013 time period because these data represent the most recent certified data available in August 2014 at the time the EPA notified states of any intended revisions to the states’ and tribes’ designation recommendations. Howe ver, because the EPA is making final designation decisions in December 2014, we beli eve it is appropriate to allow interested states and tribes to early certify thei r 2014 data ahead of the May 1, 2015 deadline specified in 40 CFR part 58.15(a )(2). States and tribes wish ing to certify and submit their 2014 data for consideration in final designa tion decisions, should submit the certified 2014 data for all monitors in the desired area by February 27, 2015. The EPA established this deadline to ensure that we would have adequate time to evaluate the new technical information and complete the interactive pr ocess between the EPA and the states, as contemplated by the Act, as we dete rmine the final area designations.

Comment: State commenters, incl uding Alabama and Texas, note that through the regulatory provisions in 40 CFR Secti ons 50.13 and 50.18, the EPA establishes the requirements for operating state ambient air qua lity monitoring networks. The EPA then verifies through technical systems audits that air agencies are following these requirements. The EPA also uses these monito ring data to determine when the primaryResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 7 of 68 and secondary PM 2.5 NAAQS are met. The commenters beli eve that unless these criteria are not met, areas with monitor values that meet the specified criteria should be designated attainment. The commenters believ e a designation of “attainment” is further supported by the definitions in the Clean Air Act. CAA sections 107(d )(1)(A)(i), (ii) and (iii) (42 U.S.C. 7407) which provide definitio ns for “attainment,” “nonattainment,” and “unclassifiable,” but do not include a definition for “unc lassifiable/attainment.” Commenters note that the EPA uses the category “unclassifiable/attainment” “ without clear definition, criteria

, or st a t utory basis” to designate those areas that are monitoring attainment and for areas that do not have monitors but for which the EPA has reason to believe ar e likely attainment and are not contributing to nearby violations. The state

commenters recommend that areas monitoring attainment should be designated as attainment in December 2014.

EPA Response: In the April 16, 2013, guidance Initial Area Designations for the 2012 Revised Primary Annual Fine Particle National Ambient Air Quality Standard, the EPA said that states could submit recommendations identifying areas as “a ttainment,” but that the EPA expected to continue to use th e “unclassifiable/attainment” category for designations for the 2012 annual PM 2.5 NAAQS. ( See footnote 2 at page 2). As we have done with past initial area designation efforts for other NAAQS, for these designations, the EPA is using a designation category of " unclassifiable/attainment" for areas that are monitoring attainment and for areas that do no t have monitors but for which the EPA has reason to believe are likely attainment and are not contributing to nearby violations. The EPA is using “unclassifiable” for those area s where the EPA was not able to determine based on available information whether the area is meeting or not meeting the NAAQS, or where the EPA was not able to determ ine that the area cont ributes to a nearby violation.

Comment: One commenter expresses concern about the EPA’s proposal to designate numerous areas as “unclassifiable” based on data quality and completeness issues. The commenter notes that because the EPA has hi storically treated unclassifiable areas as though they meet the standard and are not subj ect to the stronger protections required for nonattainment areas, the EPA is effectivel y denying millions of people the protection they deserve under the standard. The commenter adds that under previous designations efforts, the EPA has taken the position th at once it has designated an area as unclassifiable, the Agency had no obligation to redesignate the area, even if adequate data showing nonattainment beco me available. The commenter adds that following this course of action encourages states to “follow sloppy or deficient data collection and analyses” because it results in the “rewar d” of avoiding a nona ttainment designation.

The commenter recommends that the EPA pursue the following:

 For historically nonattaining areas (i.e ., Chicago, St. Louis, Atlanta, and Knoxville) with invalid or incomplete 2011-2013 data, use the most recent prior years for which adequate, qua lity-controlled data show violation of the 2012 annual PM 2.5 NAAQS unless the EPA provides evidence showing that air quality has improved and no longer violates the st andard (treating such areas as anything other than nonattainment is arbitrary and unlawful).Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 8 of 68  Alternatively, extend the time for promulga ting final designati ons by the additional year provided under 42 U.S.C. §7407(d)(1 )(B)(i) for the portions of the eight states/territories for which the EPA is proposing unclassifiable designations based on data quality/completeness issues (Puert o Rico; U.S. Virgin Islands; Atlanta, Glynn County and Dougherty County, Georgi a; Tennessee (except Chattanooga); Illinois; St. Louis, Missour i; and areas of Indian Count ry, CA). Commenter notes that the EPA has proposed to provide such an additional year for designations in Georgia, and there is no r eason to take a different appr oach as to the other areas with data adequacy and quality issues.

 As was done with the recent 1-hour sulfur dioxide standard, develop a plan to designate areas with insufficient monitoring data based on modeling or additional monitoring.

 The EPA must also put in place steps to work with the states and tribes to review the available data and to expeditiously upda te the laboratory systems to restore the quality controls needed for the data measurement.

EPA Response: The EPA appreciates the commenter’s concerns and acknowledges that the extent of incomplete/invalid data associat ed with the initial area designations for the 2012 annual PM 2.5 NAAQS is unprecedented. The EPA also agrees with the commenter that it makes sense to extend the time for pr omulgating designations using the authority provided under section 107(d)(1 )(B) of the CAA. As such, the EPA is deferring initial area designations for ten areas where curren tly available data, including air quality monitoring data, are insufficient to determin e whether the areas are meeting or are not meeting the NAAQS. For these areas (i.e., Atlanta, GA; Albany, GA; Augusta, GA-SC; Brunswick, GA; Columbus, GA- AL; Savannah, GA; Valdosta , GA; Washington Co, GA; the entire state of Florida; and the entire state of Tenness ee, excluding three counties in the Chattanooga area), the EPA believes that additional air quality monitoring data will result in complete and valid data suffici ent to inform a designation determination.

In this action, the EPA is finalizing a desi gnation of unclassifiable for those remaining areas identified as “unclassifiable” in the 120-day letters (i.e. Puerto Rico; US Virgin Islands; and the entire state of Illinois, including two countie s in Indiana as part of the Chicago area and four counties and one city in Missouri as part of the St. Louis area) because these areas have ambien t air quality monitoring sites that lack complete data for the period 2011-2013. After reviewing the ambien t air quality monitoring data for these areas for 2012, 2013 and 2014, the EPA believes that near-term data will continue to be insufficient to determine valid design values and, therefore, that deferring designations would not be helpful. Additionally, a review of data prior to 2013 indicates similar data quality and/or completeness issues such that the EPA lacks the confidence in historical data needed to support a designation based on recent prior years. The EPA is working closely with the appropriate air agencies to ensure that complete, quality-assured data are gathered moving forward and will continue to conduct technical syst ems audits of each ambient air monitoring organization every 3 years as required under 40 CFR part 50, Appendix A. The EPA will evaluate complete and valid data for “unclassifiable” areas when they become available.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 9 of 68 3.1.2. Requests to Extend the Public Comment Period

Comment: Two commenters requested that the EP A extend the deadline for the public comment period beyond September 29, 2014, to allow interested parties additional time to review docket materials and provide substantive comments.

EPA Response: In its August 29 Federal Register notice (79 FR 51517) announcing the availability of the EPA’s responses to stat e and tribal designation recommendations for the 2012 annual PM 2.5 NAAQS, the EPA invited public comment through September 29, 2014. In the “120-day” letters, the EPA asked st ates and tribes to provide any additional comments by October 29, 2014. The EPA establis hed these staggered deadlines to allow the states and tribes to addr ess any public comments and to allow the EPA to review and respond to all significant public , state, and tribal comments in advance of promulgating the initial area designations in December 2014 according to our statutory designations deadlines. For these reasons we were unable to extend the comment period.

3.1.3. Other General Comments

Comment: One commenter noted that the regulatory burde n associated with the EPA’s process of designating nonattainment areas will negatively affect areas by causing economic harm.

EPA Response: Section 107(d)(1) of the CAA direct s the EPA to designate an area “nonattainment” if it is viola ting the NAAQS or if it is cont ributing to a violation of the NAAQS in a nearby area. The first step in de signating nonattainment ar eas is to identify air quality monitoring sites with 2011-2013 data that show a violation of the 2012 annual
PM 2.5 NAAQS. To determine whether a nearby ar ea is contributing to a violation, the EPA recommended that states conduct a techni cal analysis based on a number of factors listed in the designation gui dance for the 2012 annual PM 2.5 NAAQS, including air quality, emissions and emissions-related data, meteorology, geography/topography, and jurisdictional boundaries. In evaluating whether to modi fy a state’s designation recommendation, the EPA also considered t hose factors as documented in the EPA’s technical support document for the identified no nattainment area. In determining whether an area should be designat ed nonattainment under section 107(d), the EPA did not consider economic impacts because they are no t relevant for determining whether an area is violating the NAAQS or is cont ributing to a nearby violation.

Control obligations in areas design ated nonattainment for the 2012 annual PM 2.5 NAAQS will be addressed through a separate implementation rulemaking. As the EPA considers the required components of implem entation plans for the 2012 annual PM 2.5 NAAQS, the Agency intends to provide states flexibility and opportunities to maximize efficiency to the extent such approaches are consistent with the CAA and will not jeopardize expeditious attainment of the public health a nd welfare goals of the CAA. In addition, the EPA is exploring ways that it can provide assist ance to the states on this issue. Finally, to the extent the CAA does not mandate specifi c control measures, states may consider economic concerns in development of their state implementation pl ans to address air quality.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 10 of 68 3.2 Area-Specific Issues

3.2.1. EPA Region III

Comment: Pennsylvania Department of Envi ronmental Protection (PADEP) and Allegheny County Health Department (ACHD) urged the EPA to reconsider its intended boundary from that of Allegheny County to th e historical five borough Liberty-Clairton boundary that has served as the bounda ry for this area in the past PM 2.5 designations, given that the only violating monitor is the same monitor the EPA relied upon for its past designations under the annual and 24-hr PM 2.5 NAAQS designations. All other monitors located in the County are not only currently attaining the standard, but demonstrating a historical downward trend that provides c onfidence in continuing attainment of the standard.

Commenters stated that it is inappropri ate for the EPA to expand its nonattainment boundary for the Liberty-Clairton area to in clude the entirety of Allegheny County and that the historical boundary for Liberty-Clairton is appr opriate given that the only violating monitor is located within the historical boundary.

The commenters noted that the Liberty monitor is located in an area that has historically demonstrated a very significant localized indus trial impact that requ ires separate planning approach that the EPA has recognized in past designation processes. However, commenters claimed that in the initial TSD for Allegheny County, the EPA ignored precedent and attempted to link sources in other parts of the County including the urbanized area of the City of Pittsburgh to a violating monitor that is subject to a unique mix of meteorology topography and localized emissions. The Commenters argued that the EPA’s justification for the entire County is confusing, becau se in several instances the EPA cited the “dominant” influence of local emissions on the Liberty monitor.

EPA Response: Section 107(d)(1) requires the EPA to designate as nonattainment not only any area that violates the NAAQS, but also any area that contributes to ambient air quality in a nearby area viol ating the NAAQS. The EPA has therefore always based its nonattainment decisions upon a full comprehens ive factor-based analysis, taking into consideration all aspects that drive violations of the standard both in areas violating the NAAQS and also in nearby areas contributi ng to areas violating the NAAQS. However, the EPA must also evaluate contribution from all nearby areas portion of the area of in the analysis.

Our current Allegheny County boundary decision for the 2012 PM 2.5 NAAQS is based on only a single violating monito r -- the Liberty monitor which also formed the basis for past Liberty-Clairton PM nonattainment areas. Though there is only one violating monitor in the larger Pittsburgh CBSA, all n earby emissions sources in the area must be a evaluated for potential contribu tion to the violating monito r. Based on the EPA’s five factor analysis and additional analysis performed in response to the commenters’Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 11 of 68 analysis, sources within Allegheny County out side the local Liberty-Clairton area are contributing to the viol ating Liberty monitor.

The EPA reviewed the commenters’ supplemen tal information and analysis, and agrees with the commenters, to some degree, with their technical analysis as it relates to conditions affecting the violating Liberty monitor, particularly in light of its proximity to an industrial source that cont ributes significantly to the violation, and in light of topographical and meteorological conditions pres ent at the monitor site. These conditions and the EPA’s additional analysis of the co mmenters’ information provided and further explained in responses throughout th is section and in the TSD.

Although the EPA agrees to some extent wi th the commenters’ supplemental analysis with respect to the significant contributor to the violation, the commenters’ analysis focuses on a significant contribution and doe s not address or di sprove potential contribution to the violation from nearby s ources in the remainder of the county (e.g., mobile, area, and point emission sources). The commenter primarily notes that the localized Liberty-Clairton area is a “significa nt contributor” to th e violating monitor; however, the statute is clear in providing for inclusion in nonattainment areas of areas that “contribute” to the viola tions. The EPA interprets the term “contributes” to mean contributes sufficiently to justify inclusi on in the nonattainment area, and the EPA’s multifactor test with the various analytical tools is intended to assure an objective evaluation of the appropriate facts on a cas e by case basis in each area. The EPA has considered multiple factors of analysis, and ha s applied the same analysis to all counties considered in the area of analysis as outlined in the TSD. The EPA’s decision is not contingent on only one part of the analysis, but the analysis as a whole especially given that PM is a complex pollutant with contri bution from multiple source categories as well as multiple pollutants. Hence, the EPA’s use of the weight of evidence approach evaluating the facts and circumstances in ea ch area on a case by case basis, and was done consistently with decision principles to assure comparable treatment in all the designations.

As demonstrated by the five factor analys is in the TSD for the Allegheny County area and supplemental analyses performed in light of the commenters’ additional information, the EPA has determined that though there is significant contribu tion from the local sources to the violating mon itor, there is also contribution from sources within the remainder of Allegheny County imp acting the violating monitor.

The commenters’ focus on data from the viol ating Liberty monitor furthermore does not assess what is happening on all days versus high days for the annual PM 2.5 NAAQS. To further assess this potential for broa der contribution, the EPA conducted its own additional analysis of monitor concentrations and wind directions for all days in a period between 2011 and 2013. This analysis, further explained in the TS D, shows that under certain conditions on a large number days that there is some degr ee of contribution from sources in the surroundin g Allegheny County area to the vi olating Liberty monitor.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 12 of 68 Comment: PADEP and ACHD are concerned that in clusion of the entirety of Allegheny County in the nonattainment area would subject all sources therein to Reasonable Further Progress (RFP) requirements, increasing the ba seline for RFP and resulting in a greater emission reduction required to meet RFP. Commenters assert th at there are limited remaining emission controls available in the remainder of the County, and that ACHD has limited control over emissions from transportation sources in the county.

The commenters state that designation of th e entire county as nona ttainment for the 2012
PM 2.5 NAAQS would result in three different nonattainment boundary areas in the same County (1997/2006 PM 2.5 , 2012 SO2, and 2012 PM 2.5 NAAQS). The commenters allege this is not consistent with the EPA’s recen t SIP improvement outreach efforts and would place a considerable burden on resources for the ACHD. It is also important to note that the significant stationa ry sources in other areas of the County besides the Liberty-Clairton area will be subject to an y controls that are requ ired to meet the 2012 SO 2 NAAQS.

EPA Response: The EPA notes its willingness and capab ility to work closely with state partners in their development of attain ment plans. The EPA also acknowledges the commenters’ concern regarding attainment planning, however th e statutory basis for area designations is not one of whether sources are controlled or controll ed adequately at the time of designations. The issue is also not wh ether sources can or should be controlled for purposes of implementing the NAAQS. That ques tion is something that is evaluated in the context of the attainment plan that the st ate will develop once an area is designated as nonattainment. Whether sources in an area are already adequately controlled for a prior
PM 2.5 NAAQS because of existing attainment plan SIP measures for that NAAQS is also not a singular deciding factor in determini ng designations for a new NAAQS because the emissions from sources (controlled or uncontrolled) may still be contributing to a violation of the more stringent 2012 PM 2.5 NAAQS. With respect to the commenters’ contention regarding expanded RFP requirement s as a result of a broader nonattainment boundary, each NAAQS must be evaluated on the basis of violations of that standard, current ambient air quality, and the contri bution to the violation from within the established nonattainment boundaries., Designa tions determinations are therefore irrespective of RFP consequences which are statutorily addre ssed in separate, subsequent attainment planning.

With respect to the selection of jurisdicti onal boundaries for the area, each NAAQS must be evaluated independently of the other. The EPA does consider the historical jurisdictional boundaries in our intended designations while we attempt to align boundaries and overlap jurisd ictional control when determining boundaries for a new NAAQS. Boundaries however may vary fo r different NAAQS based on the source contribution and location of violations specific to each NAAQS. The EPA has given consideration to jurisdiction issues in th e Allegheny County desi gnation, but based on its analysis of the potential for sources in the ar ea to contribute to the violating monitor, the EPA has determined the Allegheny County de signation is appropriate though it may differ from the historical jurisdictional bounda ries for this area. The EPA acknowledges and appreciates that PM 2.5 planning for this area is under ACHD and PADEP’s jurisdiction, and that both agencies have a l ong history of cooperati on for planning in the Allegheny County area.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 13 of 68 Comment: PADEP and ACHD assert that the EP A dismissed the influence of industrial (stack) emissions from Washington County including two nearby power plants due to complex terrain, but ignored the same complex terrain in an attempt to link ground level, urban emissions from the City of Pittsburgh from a greater distance as a contributor to the Liberty monitor. Commenters further allege this is also despite the fact that the Liberty monitor only violates the standard when the prevailing wind is from the South or Southwest and not from the Northwest which is the direction of the City of Pittsburgh.

Commenters also argue that there is a mon itor located only 3.5 miles from the Liberty monitor in Clairton that consistently reads 3 to 4 μ g/m 3 lower than Liberty (among the lowest readings in the County) which does not demonstrate urban influence on the area. Commenters argue that the EPA is inconsistent in its reasoning for Pittsburgh’s influence on the Liberty monitor while ignoring the gr adient between the nearby, upwind Clairton monitor, which reinforces the well unders tood localized emission impact of the local source on the Liberty monitor.

EPA Response: As explained in the TSD, the EPA has analyzed contribution from the entire CBSA for this area. The EPA’s deci sions for inclusion of Allegheny County and not Washington County are set forth in th e TSD, and have not changed based on supplemental analysis submitted by commenters in response to the intended designations. Emissions in Washington County are relativ ely low, less than a quarter of Allegheny County’s emissions. Washingt on County also has relative ly low population, population density, and VMT. Furthermore, POM and EC, the largest components of the urban increment at the violating monitor, are lo w in Washington County. As explained in the TSD, the two point sources with emissions of greater than 500 tpy in Washington County have very low direct PM 2.5 and VOC emissions, which i ndicates that any potential contribution to the POM and EC in the ur ban increment at the Liberty monitor is relatively low.

The surrounding Allegheny County area is the largest source of relevant emissions in the area of analysis, and other factors such as meteorology and topography as further explained in the TSD justify inclusion of Allegheny County in the nonattainment area. In response to PADEP’s and ACHD’s supplemen tal analysis, the EP A conducted additional analysis to evaluate contribution from A llegheny County to the Liberty monitor. This additional analysis shows that based on a revi ew of all days, as is appropriate for an annual NAAQS, rather than only high concentr ation days, there is contribution on some days and wind conditions from the surroundi ng Allegheny County area on the violating monitor.

With respect to the commenters’ contention regarding concentration gradients between the nearby Clairton and Liberty monitors, the EPA agrees that this shows evidence of significant local contribution. However, as explai ned in detail in a previous response, the statute is clear in providing for inclusion in nonattainment areas of areas that “contribute” to the violations. A high or low monitored co ncentration at an attaining monitor does not by necessity preclude contri bution from the surrounding ar ea of analysis. This contribution is measured through a considera tion of all available information, through aResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 14 of 68 five-factor analysis. The overwhelming local contribution from Libe rty-Clairton sources does not preclude possible contribution from surrounding areas, and as further explained in the TSD, the five factor analysis i ndicates contribution from the remainder of Allegheny County outside the lo cal Liberty-Clairton area.

Comment: In response to the EPA’s August 19, 2014 120-day letter, PADEP and ACHD submitted information on historic trends for monitored annual means and design values for monitors in Allegheny County. The commen ters contend that the information shows that the Liberty monitor is unique compared to all other monitors in Allegheny County, exhibiting both higher PM 2.5 quarterly means and design values and poor correlation to all other county monitors , indicating local impact on this monitor by the nearby Clairton Coke Works. Commenters argue that the Libe rty monitor is unique from other Allegheny County monitors due to this downwind pr oximity to the source, as well as microclimatological and topographical impact s related to the m onitor’s location on a bluff over the river valley and the source.

EPA Response: The EPA acknowledges the commenters assertion that the provided annual means and annual design value graphs for the Allegheny C ounty monitors show that the Liberty monitor is higher than the other monitors in the county and follows a similar downward trend as the other monitor. This supports the EPA’s quarterly means analysis and conclusion that the Liberty m onitor is influenced by the same seasonal patterns as the rest of th e area but an additional local component is causing the exceedance in PM 2.5 concentrations. However, secti on 107(d) of the CAA directs the EPA to designate an area nonattainm ent if it is violating the NAAQS, or if it is contributing to a violation of the NAAQS in a n earby area. Though the EPA agrees with the commenters that a local component is causing the exceedance of the NAAQS, the commenters do not disprove that emissions from Allegheny County are not contributing to the exceedance. As explai ned throughout the TSD, the EP A’s five factor analysis demonstrates contribution from Allegheny Count y to the violating Liberty monitor. The EPA acknowledges the topography and temperatur e inversions in the Liberty-Clairton area also probably cause local emissions to be trapped in this area and drive the violation of the NAAQS at this monitor. However, the statue compels the EPA to consider contribution to a violation of the NAAQS and not necessarily causation. In an attempt to better understand the meteorological impacts at the Liberty monitor, the EPA performed additional analysis of conditi ons at this site (see PA TSD pages 111 – 115). The EPA’s analysis also shows that unde r certain conditions on a large number days there is some degree of contribution from sources in th e surrounding Allegheny County area to the violating Liberty monitor, therefore the topography and inversions do not preclude transport of emissions from outside this sm all area and that emissions from Allegheny County are capable of bypassi ng these features to impact the violating monitor.

Comment: As part of their supplemental analys is submitted in response to the EPA’s August 19, 2014 120-day letter, PADEP and ACHD examined speciation data for select tri-state monitoring sites (bot h inside and outside the area of analysis) for the period between 2011-2013, in an a ttempt to characterize PM 2.5 contribution at the violatingResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 15 of 68 Liberty monitor. Commenters used a numb er of area monitors to assign allegedly incremental contribution from various part s of the area of analysis as regional background, the surrounding Pittsburgh MSA, the Pittsburgh urban area, and local sources within the Liberty-Clairton area.

The commenters assert that the re sults of that analysis show that the Liberty monitor sees higher levels of elemental carbon and chlori ne than other area monitors while other species, including sulfates and organic car bon, are more normalized in comparison of Liberty monitor levels to those seen at othe r tri-state monitors. Commenters assert that the allegedly incremental contribution anal ysis indicates that the surrounding MSA monitors show a large incremen t of organic carbonaceous mate rial, indicative of a large, widespread contribution of area, mobile a nd point source emissions and that the rural background sites show large cont ributions of sulfate, nitrat es and a portion of organic carbonaceous material, indicative of widespr ead regional transport. Commenters also assert that the Pittsburgh urban area contributes only an incrementally small portion of the total from the tri-state area to the Libe rty monitor, and that the excess contribution generated nearby to the Liberty monitor c ontains high levels of carbon, sulfates and elemental carbon PM 2.5 components, which can be attrib uted to the nearby industrial sources, such as the Clairton Coke Works source.

EPA Response: The EPA’s approach to designations is to evaluate the entire CBSA and not differentiate between the MSA and the ur ban area within the CBSA. In addition, the EPA notes that the entire CBSA is appropriate for evaluating whether sources in this area are contributing to a violation within the County or within a nearby area.

The EPA’s SANDWICH speciation data suppor ts the commenters’ assertions with respect to some unique speciation results at the Liberty monitor in comparison to other area monitors. The EPA agrees that the commen ters’ analysis of com ponent speciation at the Liberty monitor compared to other area monitors s hows heavy local industrial contribution of elemental carbon and chlorine components not seen at other monitors, as well as similar presence of components lik ely representing regi onal background (e.g., ammonium sulfates and ammoni um nitrates). However, th e analysis done by PADEP and ACHD does not account for high organic car bon and sulfate components at Liberty in comparison to these other area monitors which likely result from contribution to the Liberty monitor from sources outside th e Liberty-Clairton local area and within Allegheny County. There are other mobile, ar ea and point sources in Allegheny County with organic carbon and sulfate emissions that have the potential to contribute to the Liberty monitor.

The commenters’ area contribution analysis app ears to show some in crement from within the Pittsburgh urban area to the violating Liberty monitor, indicat ing the existence of contribution to the violation from within Allegheny County. The commenters describe this contribution as an “incrementally sma ll portion of the total,” but the EPA through its five factor analysis has determined that there is contribution from the Allegheny County area to the Liberty monitor sufficient to just ify inclusion of the entire county in the nonattainment area, and the commenters ha ve not rebutted this determination.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 16 of 68 After review of the commenters’ supplem ental analysis to the EPA’s intended designation, while there is clea rly contribution from local s ources in the Liberty-Clairton area, it still appears from the evidence provide d that there is some degree of contribution to the violation at the Liberty monitor from emission sources in Allegheny County based upon speciation data, emissions da ta, meteorology, and other fact ors as described in this
TSD.

Comment: In response to the EPA’s August 19, 2014 120 day letter, PADEP and ACHD provided updated 2013 emissions for sources generating over 500 tons per year in Allegheny County. Seven of the nine of these sources have decreased particulate matter and PM precursor emissions from 2011 to 2013, while emissions across the entire county were reduced emissions by 26.3%. Convers ely, the Clairton Coke Works (e.g., the nearest major emissions source to the viola ting Liberty monitor) increased its emissions between 2011 and 2013, as a result of ongoing issu es with some of its newer emissions controls. The nearby U.S. Steel Irvin Plant (2 miles from the Liberty monitor) also increased emissions, to a lesser degree, over th at same period. Further, five coal-fired power plants inside the EPA’s area of anal ysis, but outside Alle gheny County (two in Washington County, one in Greene County, and one in Preston County, WV) have deactivated since 2011.

EPA Response: The EPA agrees with PADEP and ACHD that the most recent updated emissions data for sources in Allegheny Count y indicates that major point source facility emissions in Allegheny County ha ve decreased, in their totality (except for the Clairton Coke Works and U.S. Steel Irvin facilitie s). However, while their impact on total emissions for Allegheny County are less in rela tion to total county emissions, these major facility revised emissions likely have some impact on the violating monitor

Comment: PADEP and ACHD also provided M odeled Attainment Test Software (MATS) unmonitored area PM 2.5 impacts from a baseline year of 2007 to a projected 2014 (performed for the 2006 24-hour PM 2.5 NAAQS SIP) to support their position. Commenters assert that the modeling results sh ow distinct border for the extent of urban impacts in the Pittsburgh area compared to Liberty-Clairton impacts. To further demonstrate the allegedly unique emissions and the source of these emissions at the Liberty monitor, PADEP and ACHD submitted updated PMF source modeling. The commenters assert the Liberty monitor shows a large carbon-rich industrial source which is not present at other sites, and that the Liberty monitor also s hows little motor vehicle emissions and that motor vehicle emissions from the Pittsburgh area are not transporting to the Liberty monitor.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 17 of 68 EPA Response: The EPA notes it does not rely on modeling forecasts when making decisions regarding NAAQS designations, as designations are base d upon recent ambient air quality data and not future projections of air quality. The MATS modeling provided by PADEP and ACHD for 2007 and 2014 does s upport the commenters’ contention that ambient PM 2.5 is concentrated in two separate plum es – one centered over the urban core of Pittsburgh and another separate plume over Liberty-Clairton area. However, the MATS modeling does not actually prove that th ere is no contribution from the remainder of Allegheny County to the Li berty monitor – instead it sh ows only that the largest sources of contribution at Li berty is from the local source. For reasons explained throughout the TSD, the five factor analysis demonstrates there is contribution from the remainder of Allegheny County to the violating monitor.

The EPA acknowledges that a carbon-rich indus trial source contribu tes to the Liberty monitor as shown in the PMF common s ource model analysis. The commenters’ provided PMF common source factor modeling analysis also demonstrates that the Liberty monitor detects source types si milar to other area monitors for PM 2.5 components typically associated with regional background (e.g., sulfat es, nitrates and crustal). However, the PMF source factors for the Libe rty monitor also show the appearance of
PM 2.5 components from motor vehicle and burni ng/cooking sources at levels similar to other area monitors. Given the lower populat ion and vehicle-rela ted activity in the vicinity of the Liberty monitor in compar ison to other area mon itors, the presence of motor vehicle and burning/cooking sources at le vels similar to other area monitors does not disprove and actually could indicate cont ribution from outside the Liberty-Clairton area from at least those two source types. While the PMF modeling clearly shows a contribution from a local industrial sources, it does not rule out contribution from other sources in the County, particularly burning and motor vehicle sources.

Comment: PADEP and ACHD provided additio nal Allegheny County population information in response to the EPA’s 120 day letter, focusing on population spatial allocation and population density. The agencies assert population in the metropolitan area is further removed from the violating monitor than is in dicated by countywide data, and that the populations in the Li berty-Clairton area have been in decline by 13.4% for the period between 2000 and 2010. Commenters assert that this newly provided population data show that the majority of urban population-based area source and mobile source emissions created in the urban Pittsburgh por tion of Allegheny County do not contribute significantly to violation at the Liberty monitor.

EPA Response: While the commenters updated population data shows a more recent decline for the Liberty-Clairton area and that m obile emissions in this area contribute to a much lesser degree than local industrial sources , this does not eliminate the potential for emissions contribution to the vi olating Liberty monitor from the much larger source of population-based emissions from the more popul ous and heavily trafficked remainder of Allegheny County. Allegheny County has by fa r the largest popul ation and population density, and vehicle miles travelle d, relative to all other areas within the area of analysis for the violating Liberty mon itor. As previously discussed, the statute is clear in providing for inclusion in nonattainment areas of areas that “contribut e” to the violations.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 18 of 68 The EPA interprets the term “contributes” to mean contributes sufficiently to justify inclusion in the nonattainment area. As demons trated by the five fact or analysis in the TSD for the Allegheny County area and supplemen tal analyses performe d in light of the commenters’ additional information, the EP A has determined that though there is significant contribution from th e local sources to the viola ting monitor, there is also contribution from sources within the re mainder of Allegheny County impacting the violating monitor justifying in clusion of the entire county in the nonattainment area.

Comment: PADEP and ACHD provided additional meteorology data in response to the EPA’s 120 day letter. Commenters provide d updated wind rose and temperature inversion information at the Liberty monitor site as well as several HYSPLIT trajectories for the area. Commenters assert that the EP A’s TSD only looked at airport data and did not evaluate local meteorological site at the Liberty Borough site. Commenters emphasize that the newly provided 2009-2013 wind rose at the Liberty Borough site demonstrates a preponderance of winds from the south through west with a dominant southwest component, further supporting thei r contention that the Liberty monitor is largely influenced by the Clairton Coke Work s facility. PADEP and ACHD argue that the EPA did not address stagnation conditions at the Liberty monitor from frequent local inversion conditions that trap PM2.5 emissions at the monitor. The commenters provided inversion statistics for 2009-2013 to support th is position that shows 40% of the days when data is available are impacted by inversions.

EPA Response: The EPA agrees with the commenters that the regional wind direction closest to the Liberty monitor is from th e south and the west with southwesterly components, however, there is still contributi on from other sources as winds come from other directions. As discussed in the TSD, the wind rose closest to the Liberty monitor shows strong southerly and westerly compone nts, with southwesterly and northwesterly components. The northwesterly component indi cates that the highly urbanized Pittsburgh area is upwind of, and theref ore contributing to, the Libe rty monitor. Further, as discussed in previous responses, the EPA’s additional analysis (see PA TSD pages 111 – 115) also shows that under certain conditions on a large number days there is some degree of contribution from sources in th e surrounding Allegheny County area to the violating Liberty monitor. In addition, mete orological data from the Liberty Borough monitor is not regularly uploaded or quality assured by the EPA. Airport meteorological data has a higher level of quality assuran ce and the EPA must rely on highest quality available data when determining nonattainment boundaries.

As explained in previous responses as well as in the TSD, the EPA acknowledges the low level, diurnal inversions in the Libe rty-Clairton area also probably cause local emissions to be trapped in this area and driv e the violation of the NAAQS at this monitor. However, the statue compels the EPA to c onsider contribution to a violation of the NAAQS and not necessarily causation. The EPA’s analysis (see PA TSD pages 111 – 115) also shows that under certain conditions on a large number days there is some degree of contribution from sources in th e surrounding Allegheny County area to the violating Liberty monitor, therefore the topography and inversions do not precludeResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 19 of 68 transport of emissions from outside this sm all area and that emissions from Allegheny County are capable of bypassi ng these features to impact the violating monitor.

Comment: A letter from the Allegheny Conference on Community Development to Dana Aunkst, Acting Secretary, at P ADEP was submitted by PADEP. Allegheny Conference states that the EPA has inexp licably reversed its position recognizing the unique meteorology, topography and localized emissions in the Liberty monitoring area without justification. The commenter asserts th at the EPA’s intended designation of all of Allegheny County is not supported by ev idence. Allegheny Conference believes designating the entire county of Alle gheny County as nonattainment would place unwarranted requirements on ar eas that do meet the 2012 PM 2.5 NAAQS standard and urges the EPA to keep the nonattainment area to the current Liberty-Clairton boundaries.

EPA Response: The EPA disagrees with the comme nter’s contention that we have inexplicably reversed our hi storic position regarding th e allegedly unique conditions affecting the Liberty monitor. Based on the evidence and its analysis regarding meteorology, topography, and other factors as explained in the TSD, the EPA has determined that sources within all of Alle gheny County are contribu ting to the violating Liberty monitor and therefore ju stify inclusion of the entire county in the nonattainment area. Therefore, the requirements that resu lt from this designation are warranted based upon the EPA’s determination that sources from within the en tire Allegheny County contribute to the vi olating monitor.

Comment: The Pennsylvania Department of Environmental Protection (PADEP) disagrees with the EPA’s intended tw o-county Allentown nonattainment area (Northampton and Lehigh Counties), instead arguing that the boundary should be limited to the county with the violating monitor (Northampton County) -- per PADEP’s July 2014 updated recommendation. PADEP maintains th at the violation at the Freemansburg monitor in Northampton County (Northampt on County violating monitor) was caused by a fine particulate problem of an “extreme lo cal nature” that was impacted by construction associated with the redevelopment of nearly 1,800 acres of the former Bethlehem Steel Corp site located 1.5 miles south of the Freemansburg monitor. PADEP conducted an additional analysis of available data and submitted supporting information to support its case on October 28, 2014. This includes updated ai r quality data, including an analysis of Allentown area monitors design value and a nnual means trends dating back to 2001, and correlation data comparing design values at the violating monitor with other area monitors. Finally, PADEP submitted updated 2013 emissions data for large point sources (over 500 tons per year) in the Allentown area and additi onal aerial photographs showing the Bethlehem Steel redevelopment site and its proximity to the violating Freemansburg monitor.

PADEP contends that the spike in annual m ean values at the Freemansburg monitor in 2010 and 2011 is both temporary in nature and anomalous compared with data from other Allentown area monitors. PADEP argues that if the violation was the result of emissionsResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 20 of 68 contribution from Lehigh County to the ne arby Lehigh Valley monitor would show similar results to the viola ting Freemansburg monitor.

In an attempt to demonstrate a unique set of circumstances at the Freemansburg monitor, PADEP also provided design value correlation da ta comparing that monitor to five other monitors in the EPA’s area of analysis. This data shows the strongest correlation between Freemansburg and Lehigh Valley monitors, howev er the relationship is much weaker in 2011 (during the period of peak earth disturba nce and construction activity at the former Bethlehem Steel site that lies just sout h of the Freemansburg monitor) versus in 2013 after the conclusion of ma jor site construction.

EPA Response: PADEP has provided only anecdotal evidence that the construction activity at the Bethlehem Steel site is causing the spike in 2010 and 2011 design values at the nearby Freemansburg monitor, lead ing to the violation of the 2012 PM 2.5 NAAQS for the 2011-2013 period. Speciation data and urba n increment data set forth in the TSD clearly indicate that organic mass and el emental carbon are the main components of
PM 2.5 at the Freemansburg violating monitor. High organic mass and elemental carbon suggest that the sources of PM 2.5 at the monitor are local in na ture, likely due in large part to locally generated emissions from mobile, area or industrial sources, and not necessarily construction activity as the commenter conte nds. Given the proximity of the construction site to the violating monitor, the EPA woul d expect to see a higher proportion of crustal material as a result of the soil disturbance and construction activity.

Furthermore, insofar as the commenter seeks to advance an argument that a local source was the cause or significant contributor to the violating monitor, section 107(d)(1) requires the EPA to designate area that are ei ther violating the NAAQS or contributing to a violation of the NAAQS in a nearby area. The statute does not require the EPA to designate as nonattainment only those areas with sources that are causing a violation of the NAAQS. Also, the EPA has interpreted “contri bution” to encompass a concept that is broader than just “significant contribution.” The EPA interprets the term “contributes” to mean contributes sufficiently to justify in clusion in the nonattainment area, and the EPA’s multifactor test with the various analy tical tools is intended to assure an objective evaluation of the appropriate facts on a cas e by case basis in each area. The EPA has considered multiple factors of analysis, and ha s applied the same analysis to all counties considered in the area of analysis as outlined in the TSD. The EPA’s analysis justifies inclusion of the Northampton and Lehigh counties in the nona ttainment area, as emissions in these counties are contributi ng sufficiently to the violating monitor.

Additionally, Pennsylvania argues that its submitted monitor design value trends for three area monitors exhibit similar patterns da ting back to 2001 (except for the 2010 and 2011 peak construction period, during which time the violating Freemansburg shows a 3 ug/m3 peak above the Lehigh Valley monitor). Howe ver, the Allentown monitor discontinued operation in 2005 and the Lehigh Valley m onitor only commenced operation in 2010, leaving the period between 2005 and 2010 with no other mon itor in the Allentown area with which to compare values to Freemans burg. Given the lack of continuously operating monitors in the area, it is impossible to draw the types of comparis ons that Pennsylvania is attempting to draw between de sign values for the 2010-11 period.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 21 of 68 Pennsylvania states that if emissions from the nearby Lehigh County were contributing to the Freemansburg monitor violation, then th ey would expect the Lehigh Valley monitor annual means would also have increased signifi cantly. The EPA contends that the lack of more than one violating monitor in an ar ea is not dispositive evidence of whether a nearby area or county contribute s to the violation of anothe r monitor, as the violation may be the result of cumulative or aggr egate impacts from th e surrounding area.

Pennsylvania argues that its correlation comparisons between regional monitors in and around the Allentown area to the Freemansburg monitor show the strongest correlation between the Freemansburg monitor and the 1.5 mile distant Lehigh Valley monitor, followed closely by the 35 mile distant Readi ng monitor. Further, PADEP argues that the correlations between Freemansburg and each of these monitors is much stronger in 2013 than it was in 2011, during the height of th e Bethlehem Steel site construction. The EPA would expect a high proportion of crustal PM 2.5 emissions component s at the violating monitor if the 2010-2011 spike (based on the st ate’s provided histor ic trend analysis) were the result of earth disturbance construc tion-related activity. Speciation data for the Freemansburg monitor provided by the EPA in the TSD does not show high levels of crustal material and PADEP’s additional speci ation analysis show high crustal material on only a small number of high monitor value days.

The Commonwealth’s analysis of correla tions between Freemansburg and other area monitors establishes a similar correlation relationship between Freemansburg to the distant Reading monitor with that of Freemansburg to the nearby Lehigh Valley monitor, including a similarly strong re lationship in 2013 versus that of the 2011, during the time representing heavy construction activity near the Freemansburg monitor. The EPA believes such a similarly strong correla tion between Reading and Freemansburg (compared with that of Freemansburg to Le high Valley) should not exist, if the Commonwealth’s hypothesis that the cause of the spike in monitor values in 2010-2011 is the result of only local construction activit y. Instead the state argues that the 35-mile distant Reading monitor exhibi ts similar design value relationships to Freemansburg due to its topographical similarity to the Freemansburg site. Gi ven the primary nature of crustal ejecta (i.e., a lack of secondary PM 2.5 component formation) and its tendency towards dispersion and dilution over dist ance, the EPA believes the correlation relationships further support our contention th at the violating monito r is showing regional level contribution of organic and elemental carbon, most likel y associated with mobile, area, and industrial sources.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 22 of 68 The Commonwealth also provided updated 2013 emissions data for large point sources (emitting more than 500 tons per year) in Northampton and Lehigh Counties. However, the provided data shows that the preponderance of emissions reductions from major point sources in the area come from Northampton County sources, with the exception of one source in Lehigh County. The reduction of point source emissions in Northampton County does not negate the EPA’s position in the TSD that there is a significant contribution of non-point (area and mobile ) emissions from both Northampton and Lehigh Counties.

After consideration of the an alyses provided by PADEP, the EPA continues to believe the nonattainment boundary for the Allentown ar ea should remain the two counties of Northampton and Lehigh.

Comment: Northampton County is expected to attain the PM 2.5 standard, based on 2014 design values, prior to the effective date of the EPA’s final designations. Once the 2014 data is received, PADEP will request withdraw al of the Allentown area as attaining the
2012 PM 2.5 NAAQS.

EPA Response: The designation decision is based on av ailable, certified data at the current time and reflects air qua lity at the current time, rather than projections of future air quality. The 2012 PM 2.5 NAAQS designations utilize the most recent certified design value data which is for 2011-2013. See Data Co nsiderations under General Issues above. The EPA notes requests from the State to withdraw an area from the nonattainment designation will be considered through the appropriate redesignations process.

3.2.2. EPA Region IV

Comment : Alabama Department of Environmenta l Management (ADEM) requested that the entire State, including Russell County, be designated as attainment, consistent with their March 2014 initial designation recommen dation. They identified that the EPA will be basing designations on the 2011-2013 m onitoring period. The design value for the Russell County monitor for this period is 11.2 μg/m 3 . They note that while they understand that the Columbus, Georgia, mon itors have insufficient data to make a designation determination for the 2011-2013 mon itoring period, the data from the Russell County monitor for this period has been qual ity assured and accepted by the EPA as valid and in compliance with the 2012 annual PM 2.5 NAAQS. For this reason, they continue to request that rather than de fer designations for Russell County, the EPA designate Russell County as attainment, with the understanding th at the designation may need to be revised if the Columbus, Georgia, monitors fail to comply with the standard for the 2012-2014 monitoring period.

EPA Response: The EPA appreciates ADEM’s re sponse to the EPA’s intended designations for Alabama area s as identified in the EPA’ s August 19, 2014, letter. The EPA acknowledges that Alabama has valid monitoring data for the Russell CountyResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 23 of 68 monitor for 2011-2013 indicating an attaining design value for the 2012 primary annual
PM 2.5 NAAQS at that monitoring location. Howe ver, Russell County is located in the core-based statistical area (CBSA) for the Columbus-Phenix City Area, and the Georgia monitor within this CBSA does not have suffi cient data for the 2011-2013 time period for the EPA to make a determination that this pa rt of Georgia is in compliance with the 2012 primary annual PM 2.5 NAAQS. Furthermore, based on th e EPA’s technical analysis (see the memorandum entitled “Georgia Deferred Ar eas - Air Quality Designations for the
2012 PM 2.5 National Ambient Air Quality Standa rd (SAN 5706)” in the EPA’s docket for this rulemaking) for the Columbus-Phenix City Area and the fact that there is currently not enough data for the EPA to make a dete rmination on whether th e monitors in the Georgia portion of this area would have design values below the 2012 primary annual
PM 2.5 standard, at this time the EPA lacks su fficient information to determine whether Russell County is contributing to a potential violation in the Colum bus-Phenix City Area. For these reasons, and because there are indicati ons that this area will have sufficient data in the near future which will allow the ag ency to make a determination, the EPA is deferring the designation for Russell County while we await forthcoming data.

Comment: Georgia Environmental Protection Divi sion (GEPD) agrees with the EPA’s intention stated in the 120- day letter to defer initial ar ea designations under the 2012 annual PM 2.5 NAAQS for Georgia counties in the Augusta, Columbus, Savannah, Valdosta, and Washington County areas (w ith the exception of Dougherty County, which is part of the Albany, GA area and was incorrec tly included as a “def erred” county in the August 19, 2014 letter but not in supporting docu mentation). GEPD also requests that the EPA similarly defer initial area designati ons for Georgia counties in the Atlanta, Brunswick, and Albany areas that were iden tified in the August 19, 2014, letter as intended “unclassifiable” area s. GEPD also respectfully re quests that the non-Georgia counties associated with the Augusta and Columbus areas be designated attainment.

EPA Response: The EPA appreciates GEPD’s response to the EPA’s intended designations for Georgia areas as identifie d in the EPA’s August 19, 2014, letter. The EPA agrees with GEPD’s response and is now deferring designations for the Georgia counties in the Albany, Atlanta and Brunswick Areas as well as the Georgia counties identified in the Augusta, Columbus, Savannah, Valdosta, a nd Washington County Areas. Currently, there is not enough data to support a conclusion regarding the likelihood that these counties ar e not violating the 2012 annual PM 2.5 NAAQS or not contributing to nearby areas that may be violating the NAAQS. However, there are indications that these areas will have sufficient data to make a determination in the near
future.

The deferred designation of the Albany Ar ea includes Dougherty County. Although the EPA identified Dougherty County in the deferr ed Albany Area in the Agency’s August 19, 2014, letter, the EPA intended to designate Dougherty County as “unclassifiable” in that letter. Given the lack of complete da ta from the Dougherty County monitor, the EPA has now decided to defer the designation for this county while the EPA awaits forthcoming data that will allow the EPA to de termine the extent to which portions of theResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 24 of 68 Albany Area are violating the 2012 primary annual PM 2.5 NAAQS, or contributing to any nearby areas that may be violating that NAAQS.

Regarding GEPD’s request for the EPA to designate as “attainment” the non-Georgia counties associated with Augusta and Columbus Areas, the EPA lacks sufficient information at this time to assess the likelihood that these non-Georgia counties are potentially contributing to viol ations that may exist in eith er the Augusta or Columbus Areas. Accordingly, the EPA is deferring designations for Richmond County, South Carolina (in association w ith the Augusta Area) and Russell County, Alabama (in association with the Columbus Area). The EPA is deferring these counties based on the EPA’s technical assessment (see the memora ndum entitled “Georgia Deferred Area Air Quality Designations for the 2012 PM 2.5 National Ambient Air Quality Standard (SAN 5706) in the EPA’s docket for this rulemaki ng) of the likelihood of contribution to potential violations in the A ugusta and Columbus Areas, on the fact that there is currently not enough data for the EPA to make a dete rmination regarding whether certain areas comply with the 2012 primary annual PM 2.5 NAAQS, and on indications that these areas will have sufficient data in the near future that will allow the Agency to make these determinations. South Carolina provided a le tter of support for th e EPA’s use of its deferral authority in this case.

Comment: The South Carolina Department of Health and Environmental Control (DHEC) agrees with the EPA’s intention stated in the 120-day letter to defer initial area designations under the 2012 annual PM 2.5 NAAQS for Aiken County, South Carolina as part of the deferred area of Augusta, GA- SC. DHEC expects that 2014 monitoring data will show that the area m eets the standard.

EPA Response: The EPA appreciates the commenters’ support.

Comment: The Tennessee Department of Enviro nment and Conservation recommends that the EPA defer initial area designations for all areas in Tennessee, except for Hamilton, Marion and Sequatchie Counties in the Chattanooga area that the EPA identified in the August 19, 2014 letter as in tended “unclassifiable/ attainment.”

EPA Response: The EPA appreciates TDEC’s respons e to the intended designations for Tennessee areas as identified in the EPA’s August 19, 2014, letter. The EPA agrees with TDEC’s response and based on its analysis of the information available, the EPA is now deferring designations for all counties in Tennessee, except for Hamilton, Marion and Sequatchie Counties in the Chattanooga Area. Cu rrently, there is not enough data in these areas to make determinations regarding the areas’ compliance with the 2012 primary annual PM 2.5 NAAQS. However, there are indications that these areas will have sufficient data in the near future which will allow th e Agency to make these determinations. As indicated in the EPA’s August 19, 2014 letter and as recommended by TDEC, the EPA is designating the Hamilton, Marion, and Sequatc hie Counties in the Chattanooga Area as “unclassifiable/atta inment” for the 2012 primary annual PM 2.5 NAAQS. The EPA is making the final designation of “unclassifiable/a ttainment” for these counties because theResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 25 of 68 EPA has sufficient data for the counties in the CBSA for the Chattanooga Area (i.e., Hamilton, Marion, and Sequatchie Counties in Tennessee and Catoosa, Dade, and Walker Counties in Georgia) to ma ke this final designation.

Comment: Sierra Club opposes the EPA’s proposal to designate the Atlanta and Columbus Areas in Georgia as unclassifiabl e and believes that th e EPA must designate these areas as nonattainment. According to Sierra Club, the EPA cannot designate these areas as unclassifiable because doing so w ould be against available data, the EPA regulations, and the EPA guidance and would s ubject Georgians to considerable health risks, including risks of increas ed mortality rates. In support of its position, Sierra Club states that:

“The Atlanta and Columbus areas have a 2010- 2012 design value that is valid and shows nonattainment, and no valid design value that co ntradicts this finding. Further, these areas include some of the most densely populated areas of the state.

“Georgia’s Recommendation concludes that that the entire state be classified attainment/unclassifiable. However, that s uggestion relies on both an incorrect period to determine the design value and inappropriate pred ictions on the part of the state. Further, it misrepresents the data available to the state. On December 13, 2013, the only complete three years of data that was available to the Georgia Environmental Protection Division was the data from 2010, 2011, and 2012. Under th e 2012 Design Value, monitors in the Atlanta and Columbus areas vi olate the NAAQS. Although Georgia tries to hide this fact by performing a series of educated guesses as to 2013 monitor readings , the data is clear that these areas violated the NAAQS under the 2012 design value.

“The April 2013 the EPA Memo directs states to use 2010-2012 data for state recommendations. That same memo then states that that 2013 monitor data may be used by the EPA to determine NAAQS designations only if valid data is available to inform the 2013 design value. In Georgia’s case, there is not enough data for the EPA to rely on the 2013 design value. As a result, the EP A’s use of the 2013 design value would be contrary to its own regulations and guidance. Further, it is the EPA’s directive under the Clean Air Act to protect both human health and the environment. As indicated in the EPA’s decision to defer designati on for other parts of Georgia, it is appropriate to take cautionary approach to protect human health.

“To err on the side of protect ing human health and provide for an adequate margin of safety, the EPA’s data conventions require le ss stringency to determine that an area is nonattainment when there is incomplete data. Under Appendix N to 40 CFR Part 50, “years with at least 11 creditable samples in each quarter shall [] be considered valid if the resulting annual mean or resulting annual PM 2.5 NAAQS quarter shall [] be considered valid if the resulting a nnual mean or resulting annual PM 2.5 NAAQS [design value] (rounded according to the conventi ons of section 4.3 of this appendix) is greater than the level of the applicable pr imary or secondary annual PM 2.5 NAAQS.” 40 C.F.R. Part 50, Appendix N, at 4.1(b). Put another way, so long as the mean results in a violationResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 26 of 68 of the NAAQS, a year’s data is considered valid if there are at least 11 creditable samples in each quarter of that year.

“It is clear that areas in Georgia violated the NAAQS under the 2012 design value, and that the 2013 design value is not valid due to data completeness issues. However, both the Georgia Recommendation and the EPA Resp onse contain discussi ons about trends on
PM 2.5 emissions and PM 2.5 precursor emissions. To the exte nt that either agency relies on these general trends to inform NAAQS designa tions, that reliance is inappropriate and misguided.

“Georgia’s assertion that lower PM 2.5 levels are due to real and permanent emission reductions for PM 2.5 and PM 2.5 precursors is completely contrary to recent permitting actions taken by the State, which found that such reductions were not permanent. For example, when it applied to convert Plant Yates to natural gas in 2013, Georgia Power asked the Georgia Environmental Protection Division (“GaEPD”) to adjust its baseline emissions rate time period because of decr eased use of its coal units. Georgia Power claimed the decreased use was due to th e Great Recession, which “officially began December 2007,” and natural gas prices, which “reached historic lows and [caused] the use of many coal-fired plants [to] decline[] drastically.” Id. at 2. Georgia EPD concurred with Georgia Power’s assessment. Georgia EPD cannot credibly claim that emissions reductions are permanent, or even that ge neral trends can be assumed going forward, after finding that the same reductions are due to cyclical changes in the economy and natural gas prices. Further, Georgia relies on Georgia Rule 391-3-1-.02(2)(sss) (‘Georgia Rule (sss)’). However, Georgia Rule (sss) ha s not been formally in corporated into the State Implementation Plan as approved by the EP A. If Georgia does intend to rely on this rule to avoid nonattainment, it must make the rule federally enforceable by incorporating it into the SIP.”

EPA Response: In the information that the Agency released on August 19, 2014, providing the intended designa tions for the Atlanta and Co lumbus Areas (amongst other areas nationwide), the EPA stated its intention to designate the Atlanta Area as unclassifiable and to defer the designati on of the Columbus Area. The EPA is now deferring designations for a number of Georgia counties in the Atlanta Area, as well as for the Alabama and Georgia counties in th e Columbus-Phenix City Area. The EPA does not currently have enough data to make de terminations regarding either the areas’ compliance with the 2012 primary annual PM 2.5 NAAQS, or the rela tive likelihood that portions of these areas are contributing to potential nearby violations. However, because the EPA expects that all monitors within these areas will have sufficient data to promulgate designations in the near future, the Agency is merely deferring designations for these areas.

For the reasons discussed above, the EPA is deferring initial area designations for both the Atlanta and Columbus Areas pursuant to its authority under se ction 107(d)(1)(B) of the Clean Air Act. The EPA expects that complete data for these areas are forthcoming, and will promulgate designations for these ar eas when it has sufficient information to do so. Designations for these Areas will be ba sed on actual data refl ecting conditions during the period relevant to the designation process; they will not be based on projectedResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 27 of 68 emission trends. The EPA provided information regarding emissions trends in its August 19, 2014, letter to the State of Georgia and associated technical support documents to better inform the public of the levels of particulate matter pollution in the Atlanta and Columbus-Phenix City Areas over time. Any forward-looking reducti ons relied upon in the designation process will have to be ba sed on actual, enforceable, and permanent reductions. Finally, the EPA did not rely on Georgia Rule (sss ) in making the decision to defer these areas.

3.2.3. EPA Region V

Comment: Ohio EPA believes that Lake County s hould be designated as attainment. The monitoring ID 39-085-0007 in Lake County is in attainment. Lake County is located east of Cuyahoga County where th e nonattainment monitors ar e located. Therefore, an easterly wind pattern would be necessary to cause emissions in Lake County to contribute to violations in the Cleveland area. Howe ver, as indicated by the meteorological wind data US EPA reported “there is a pattern across the area of predominantly south to west winds, mostly at mid-level speeds of 4 to 10 meters per second, sugge sting that potential emission sources in the south through-west upwind direction should be considered for analysis.” In addition, the eastern monitor in Cuyahoga County is also in attainment (located between Lake County and the nonattainment monitor).

The EPA also reported that Lake County emits the greatest amount of direct PM 2.5 and precursors in the Cleveland area including 44% of the SO 2 emissions. The Cleveland Electric Illuminating Company Eastlake Pl ant (Eastlake Power Plant) contributed approximately 93% of the total point source emissions evaluated for Lake County and is located 18 miles from the near est nonattainment monitor. For nearly 2 years (2013 and 2014 emission reporting years) th e largest units at the Eastla ke Power Plant, units 4 (240 MW) and 5 (597 MW), have been shutdown (g enerators have been removed and cannot resume operation). The facility has al ready made significant reductions in PM 2.5 and
PM 2.5 precursors to date. A proposed shutdown of the remaining units 1, 2 and 3 (132 MW each) by April 2015 has been submitte d for approval to PJM Interconnection Regional Transmission Organization (RTO). The proposed shut dow n of the remaining units is included in the PJM Interconnection RTO Generator Deactivation Summary Sheets available at http://www.pjm.com/planning/generationdeactivation/gdsummaries.aspx and will result in further dramatic reductions in direct
PM 2.5 and precursor emissions prior to the impending PM 2.5 annual NAAQS attainment date. Eastlake Power Plant has also informed Ohio EPA they are in agreement with zeroing out their SO 2 emissions for the purpose of fu ture attainment demonstration modeling for the 2010 SO2 NAAQS SIP document due in spring of 2015.

Ohio EPA’s recommendation that all of Lake County should be designated as attainment is further supported by HYSPLIT KDE (HYbrid Single-Particle Lagrangian Integrated Trajectory Kernel Density Estimation) plot s presented in the US EPA Cleveland TSD. The KDE plots show that for each quarte r evaluated (2010-2012) Carmeuse Lime, Incorporated - Grand River Operations, wh ich is 28 miles away from the nearest nonattainment monitor, is not located within a KDE grid with a frequency of 75% orResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 28 of 68 higher of observed trajectory endpoints. Pain esville Municipal Electric Plant, which is also 28 miles from the nearest nonattainment mo nitor, only had an estimated density in the 75% or higher range during the sec ond quarter of years 2010-2012, when the quarterly average at all of the Cuyahoga County monitoring sites was below 12.0 μ g/m 3

. If the EPA insists on including Lake County in the Cleveland nonattainment area, Ohio EPA strongly urges that only th e western portion that encompa sses the area including and west of the Eastlake Power Plant. Alt hough Ohio EPA disagrees commuter travel between Lake County and Cuyahoga County w ould warrant including Lake County in the nonattainment area, designating only the follo wing townships in the western portion of Lake County would capture the majority of commuter VMT emission between Lake and Cuyahoga Counties: Eastlake, Lakeline, Ti mberlake, Wickliffe and Willowick. These townships also surround the Eastlake Power Plan t. However, as presented in Ohio EPA's original recommendations, although the number of commuters traveling into Cuyahoga from Lake County was among the highest ev aluated, only 5.2% of the workers working in Cuyahoga County commute in from Lake County. Ohio EPA believes this small percentage of vehicle source emissions does not warrant inclusion of any portion of Lake County in the Cleveland nonattainment area.

EPA Response: The EPA agrees with Ohio’s conclu sion that Lake County should not be designated nonattainment based on contribution to violations of the NAAQS in Cuyahoga County. The EPA’s preliminary conclusion to include Lake County as nonattainment was primarily because the EPA believed at the time that Lake County emitted the greatest amount of direct PM 2.5 and precursors in the Cleveland area – over 5,000 tpy more than is emitted in Cuyahoga County. This was primar ily because the EPA believed at the time that Cleveland Electric Illuminating Compa ny Eastlake Power Plan t (Eastlake) had the highest combined emissions of any source in the Cleveland area, and also because it was only 18 miles from the design value monitor in Cleveland. However, for nearly two years the two largest units have b een shut down and the generato rs have been removed and cannot resume operation. These shutdowns are permanent and enforceable. As a result of these shutdowns, NOx emissions have been reduced by 6,204 tons per year and SO 2 emissions have been reduced by 43,264 tons per year since 2013. In addition, the remaining three smaller units are scheduled to be shut down by April 2015, although this likely future reduction did not factor into th e EPA’s analysis. This reduction in emissions from the already shut down units makes La ke County go from being the county with the greatest amount of direct PM 2.5 and precursors in the Cleveland area to one of the counties with below average emissions in the Cleveland area.

Lake County is east of and downwind from th e violating monitors in Cleveland, based on wind roses generated by the EPA for the Clev eland area, which show a pattern of predominantly south to west winds – mostly at mid-level speeds of 4 to 10 meters per second. HYSPLIT KDE plots for the Clevela nd area indicate a greater frequency of trajectories passing over grid cells to the west and sout h. In addition, only 5.2% of Cuyahoga workers commute from Lake County. While the EPA previously believed that emissions from the Eastlake Power Plant were substantial eno ugh to overcome these countervailing factors and warrant Lake County’s incl usion in the Cleveland nonattainment area, the updated information from Ohio indicates that this is no longer the

case.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 29 of 68 In conclusion the EPA agrees with Ohio that Lake County should be designated as attainment because of the very large, permanent, and enforceable decrease in point source emissions identified by Ohio, because Lake County is downwind of the violating monitors in Cleveland, and because there are only a moderate number of Lake County workers commuting to Cleveland.

Comment: Ohio EPA recommends that Lorain County be designated as attainment. Lorain County is located we st of Cuyahoga County and the Cleveland area nonattainment monitors. Monitor 39-093-3002 located central ly along the northern border of Lorain County (6 miles from Avon Lake Power Plan t) and monitor 39-035-1002 on the west side of Cuyahoga County between Lorain and the vi olating monitors are both in attainment. Avon Lake Power Plant is the only major point source in Lorain County. It is located in northeast corner of Lorain County appr oximately 19 miles from the nearest nonattainment monitor. Avon Lake Power Pl ant announced June 30, 2013 that it will be converting to natural gas; Ohio EPA gran ted a Mercury Air Toxics Toxic Standards (MATS) extension to April 16, 2016 for the facility. Ohio EPA expects that this conversion will result in dramatic PM 2.5 and PM 2.5 precursor emissions from the Avon Lake Power Plant, therefore Ohio EPA belie ves Lorain County should be designated as attainment.

The VMT in Lorain County (2,787,828,581) were the second highest in the evaluation area, but still significantly lower th an those of Cuyahoga County (8,534,134,941). However, as presented in Ohio EPA's or iginal recommendations, only 5.9% of the workforce in Cuyahoga County commutes in from Lorain County. Ohio EPA believes this small percentage of vehicle source em issions does not warrant inclusion of any portion of Lorain County in the Cleveland nonattainment area

.

EPA Response: The EPA disagrees that Lorain County should be designated as attainment. Lorain County is west of and upw ind of the violating monitors in Cleveland. This is evidenced by the wind roses that the EPA generate d for the Cleveland area, which show a pattern of predominantly south to west winds - mostly at mid-level speeds of 4 to 10 meters per second. In addition, HYSPLIT KDE plots for the Cleveland area indicate a greater frequency of traject ories passing over grid cells to the west and south. Therefore, all of the direct PM 2.5 and precursor emissions from poi nt, area and mobile sources can impact the Cleveland monitors.

Although the Avon Lake Power Plant (Avon Lake) will be converting to natural gas this will not occur until April, 2016 and there will still be significant NOx emissions after the conversion occurs. Unlike the shutdown which has actually occurred in Lake County, this scheduled conversion will not take place until we ll after the designation process and it is therefore difficult to establish the imp act of this conversion on Cleveland PM 2.5 levels.

Although only 5.9% of the workforce in Cuya hoga County commutes in from Lorain County, the VMT in Lorain County, at 2.8 million, is one of the highest in the Cleveland area. This is significant because, unlike fo r Lake County, the vehicular emissions inResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 30 of 68 Lorain County will have an impact on th e Cleveland monitors because Lorain is commonly upwind of Cuyahoga County and Cleveland.

In summary, Lorain should be de signated as nonattainment for PM 2.5 because it has the third highest amount of direct PM 2.5 and precursors in the Clev eland area, the conversion to natural gas at Avon Lake will not take place until April, 2016, it is commonly upwind of the violating monitors in Cl eveland and has significant VMT.

Comment: Ohio EPA believes that Summit County should be designated as attainment. Both of the monitoring sites (m onitor 10391530017, 391530023) located in Summit County are in attainment. US EPA consid ered Summit County in the nonattainment analysis for the Cleveland, Ohio area as well as the Canton Massillon, Ohio area. The previous Ohio EPA recommendation and analysis submitted on December 13, 2013 still holds true for Summit’s impact on violations in the Cleveland nonattainment area.

While Ohio EPA agrees that Summit County is best suited in the Canton-Massillon nonattainment area as opposed to the histor ically designated Cleveland area, Ohio EPA still asserts that Summit County should not be designated nonattainment. The three major point sources located in Summ it are within 4 miles of th e two Summit County attaining monitors. Wind data indicates that the majority of the winds near these three major point sources are westerly to s outherly which would move pollutants away from the nonattainment monitor in Stark County. The majo rity of the northerly winds observed in Summit County are low speed ranging from 2-6 mph. Back-trajectories of the first, second, third and fourth maximum concentra tion days over three years (2010-12) at the Stark County nonattainment m onitor 39-151-0017 were analyzed using NOAA's Model, HYSPLIT. The back trajectory simulations al so included the trajectories of exceedance days of 24-hr PM 2.5 standard for years 2010-12 at th e same monitor. The purpose of trajectory analyses was to determine the cause of violation by simulating the flow of 24- hour air trajectory patterns in the backward m ode. The analysis indicates that none of the 24 hour backward trajectory patterns originated from areas directly north or northeast of the monitor indicating that the trajectories were not influenced by Summit County sources. Although Summit County has the highes t VMT for the counties evaluated in the Canton-Massillon area, as indi cated in Ohio EPA's origin al recommendations, only 5.5% of the workers commuting into Stark C ounty travel from Summit County. Ohio EPA believes that this small percentage of commute rs in combination with the wind trends and beck trajectory data support a Su mmit County attainment designation.

EPA Response: The fact that the Summit County monitors are attaining the annual
PM 2.5 standard does not prove that there is no co ntribution from the ar ea to violations in Cleveland or Canton. Summit County has both significant emissions and VMT, with the second highest total emissions , third highest direct PM 2.5 emissions and highest VMT among the counties in the area of analysis for Canton, and the third highest total emissions and second highest VMT among the counties in the area of analysis for
Cleveland.

Further, the HYSPLIT modeling provided by Ohio EPA was limited in that it only considered trajectories for the four hi ghest concentration da ys and the 24-hourResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 31 of 68 exceedance days for the 2010-2012 time period. For the 2012 annual NAAQS, the monitoring data for the entire calendar year (including on days that are below the level of the NAAQS) are part of the mathematical calculation of whether a monitor is nonattainment or not. Therefore, wind direc tions during periods th at do not have high ambient levels are also relevant. Nevertheless, it can be informative to evaluate the days with monitored concentrations that ex ceed the value of the standard, 12.0 μg/m 3

, since those are the days that make a larger cont ribution towards a violation. The EPA analyzed all of the days with conc entrations exceeding 12.0 μg/m 3 during the 2011-2013 time period at the Canton design monitor, usi ng the HYSPLIT model to simulate back trajectories. Of the days with concentrations exceeding the value of the annual standard at the Canton monitor, 37% of the days have trajectories passing over Summit County. In conjunction with the emissions, meteorol ogy, and VMT data for Summit County, this data indicate that Summit County contribute s to the violations monitored in both Canton and Cleveland. Therefore, the EPA continues to conclude that Su mmit County should be designated as nonattainment because it contribut es to violations of the NAAQS in nearby

areas.

Ohio EPA indicates that Summit County is be st suited for the Cant on nonattainment area. The EPA agrees that Summit County is mo re appropriately included in the CantonMassillon nonattainment area than the Clev eland area. The major point sources in Summit County are in the southern portion of the county, closer to the violating monitor in Canton than to the violating monitor in Cl eveland. In addition, kernel density plots for Canton show a high density of trajectories covering the southern portion of Summit County. For these reasons, the EPA is desi gnating Summit County as part of the CantonMassillon area even though Summit County also contributes to th e Cleveland area.

Comment: Ohio EPA believes that the entire Wayne County should be designated as attainment. The cumulative VMT in Wayne County (1,192,145,098 miles in 2012) is less than 1/3 of the VMT in Stark County (3,838,738,336 miles in 2012), and as shown in Table 5 of the Ohio TSD, only 1.3% of the workers commuting into Stark County commute in from Wayne County. Ohio EPA be lieves this small percentage of vehicle source emissions does not warrant inclusion of Warren County in the nonattainment area. The major point sources in Wayne County ar e located approximately 18-24 miles westnorthwest of the nonattainment monitor in Stark County. Ohio EPA believes that point sources located at this great of a distance are not significantly contribu ting to violations at the Stark County monitors, especially when considering there are two major Stark County point sources located within 3 miles of the nonattainment m onitor. As reported by US EPA, the Department of Public Utilities, City of Orrville (Orville Power Plant) contributes 74% of the major point source total direct PM 2.5 and precursor emissions evaluated in Wayne County. This facility is subject to the Boiler Maximum Achievable Control Technology (MACT) rule s established in 40 CFR 63 Subpart DDDDD. It is also likely that the Orville Power Pl ant will be evaluated under the SO 2 NAAQS. Under these regulations, Ohio EPA believes that the Orvi lle Power Plant will experience significant reductions in PM 2.5 and PM 2.5 precursors prior to the impending PM 2.5 attainment date. If US EPA insists on designating Wayne County as nonattainment, Ohio EPA believes that only Orrville Township in Wayne County s hould be designated as nonattainment similarResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 32 of 68 to the approach used for designating Ashta bula Township as nonattainment for the 2006
PM 2.5 NAAQS. In this approach the emissions in Ashtabula Township (a portion of Ashtabula County, Ohio) were found to be prim arily attributable to Cleveland Electric Illuminating's Ashtabula plant and therefore onl y Ashtabula Township (rather than all of Ashtabula County) was designated as nonattai nment. Using this approach, Orrville Township would be the only portion designa ted as nonattainment in Warren County.

EPA Response: The EPA disagrees that Wayne County should be designated as attainment. Wayne County is west of th e monitor in Stark County and wind roses, pollution roses and HYSPLIT modeling all i ndicate that sources in Wayne County contribute to monitored PM 2.5 levels at the Stark County monitor. While VMT may not be particularly high in Wayne County, total emissions are higher in Wayne County than in Stark County. The majority of the emissions can be attributed to three point sources. These sources are located in the north-east qu arter of the county comprised of Baughman, Chippewa, Green, and Milton townships and th e portion of Norton C ity located within Wayne County.

Comment: We oppose the EPA's proposal to override Indiana Department of Environmental Management (IDEM ' s) recommendation . The EPA cites no issues with
IDEM ' s data

, which is complete and shows attain ment across all monitors in both counties. Instead, the EPA proposes to cha nge the designation for Lake and Porter counties to “ unclassifiable ” due to irregularities with Illinois ' sampling program

. Specifically , the EPA proposes to designate La ke and Porter counties as “ unclassifiable ” on the premise that it cannot de termine whether those counties may be contributing to a violation in Illinois

, if such a violation exis ts. All monitors in both Indiana counties demonstrate compliance with the 2012 PM 2.5 NAAQS . The EPA has not challenged the validity of that data

. Nor has the EPA identified a single violating monitor where it contends Lake and Porter counties are “ contributing” to nonattainment. Under these circumstances

, the CAA mandates an “ attainment ” designation for both counties

.

The EPA lacks authority to designate Lake a nd Porter counties as “unclassifiable.” The CAA provides three NAAQS designation categories : (1) nonattainment

, (2) attainment, and (3) unclassifiable. By explicitly de fining each category, Congress limited the discretion of states and the EPA in making designations . The EPA must designate as nonattainment “ any area that does not meet (or that contributes to ambient air qualit y in a nearby area that does not meet) the [NAAQS] for the pollutant. ” The EPA must designate as attainment “ an y area (other than an area identified in clause (i)) that meets the [NAAQS] for the pollutant. ” Areas may be designated "unclassifiable" onl y when the

area “ cannot be classified on the basis of availa ble information as meeting or not meeting the [NAAQS] for the pollutant. ” Lake and Porter counties are meeting the NAAQS and have not been linked to any nonattaining monitor

, making nonattainment and unclassifiable designa tions improper. Therefore the only designation category the CAA allows for Lake and Porter counties is “ attainment. ”

The EPA correctly concluded that Lake and Po rter counties do not meet either criterion
for a “ nonattainment ” designation. Without either (1) a nonattaining monitor in LakeResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 33 of 68 and/or Porter counties or (2) a nonattaining m onitor outside Lake and Porter counties to which these counties are contributing

, Lake and Porter counties do not fit the definition
of “ nonattainment. ” Similarly

, Lake and Porter counties do not meet the criteria for

“ unclassifiable .” An “ unclassifiable ” area is defined as one in which a lack of information prevents the EPA from de termining if the area is “ meeting or not meeting the [NAAQS]. ” There is no lack of information on the attain ment status of Lake and Porter counties

.

Unlike the definition of “ nonattainment ,” the statute does not allo w the EPA to designate an area as unclassifiable because of its potential to contribute to an unclassifiable area. The plain statutory text tellingly omits any reference to contribution

, instead focusing only on whether the county itself is meeting the NAAQS

. There is no lack of data or ambiguity on that point to support an uncla ssifiable designation. Pursuant to CAA § 107(d)(l)(A)(ii), the EPA mu st designate an area as “ attainment ” if it “ meets the [NAAQS] for the pollutant” and does not satisfy the criteria for nonattainment. That is precisely the situation in La ke and Porter counties. The EPA has undisputed information demonstrating that all monitors in Lake and Porter counties are attaining the 2012 PM 2.5 NAAQS. The EPA has not identified a single nearby monitor that is demonstrating nonattainment

, and therefore cannot c onclude that Lake a nd Porter counties are contributing to nonattainment elsewhere.

Only an attainment designation is consistent with the CAA ' s provisions for adjusting designations as new information becomes available. Specifically, CAA § 107(d)(3)-(4) allows the redesignation of Lake and Porter counties if valid data from Illinois later indicates a NAAQS violation and if the EPA demonstrates that Lake and/or Porter counties are contributing to th at violation. In the meantime , the EPA must make designations based on the information it has. That information permits only one designation for Lake and Port er counties: attainment.

EPA Response: The commenter properly quo tes the criteria in Clean Air Act section 107 for designating areas nonattainment, attainme nt, or unclassifiable, but the commenter misinterprets the criteria for being designate d attainment. At issue is two counties that themselves attain the air quality standard but that contribute to con centrations nearby that may be violating the standard. The commente r argues that a particular portion of the Chicago area (Lake and Porter Counties, Indiana) should be de signated attainment because the two counties a) meet the standa rd and b) have not been identified as a nonattainment area. However, the EPA believes that a more appropriate interpretation of the criteria for an attainment designation is whether the entire ar ea (including any portion of the area with emissions that contribute to concentrations in the area) is attaining the standard. Since the Chicago area cannot be dete rmined to be an area that is meeting the standard, the Chicago area (incl uding all portions that contribu te to concentrations in the Chicago area) does not quality fo r designation as attainment.

The EPA designates entire areas as nonattainme nt, attainment, or unclassifiable; the EPA does not promulgate separate designations for separate portions of areas. For example, in 2005, the EPA designated a Chicago PM 2.5 nonattainment area that included Lake and Porter Counties in Indiana as well as part or all of eight Illinois counties as a single combined area. This designation defined a pl anning area, triggering the applicability ofResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 34 of 68 an assortment of planning requirements unde r Section 172 and other sections of Part D among other things to provide a unified pl an by which control measures throughout the area would be considered and adopted as a ppropriate to pursue attainment throughout the area. Thus, interpreting the word “area” in Sec tion 107 as meaning the entire area that is designated as a unit is more consistent with the manner in which the EPA has historically promulgated designations and is more consiste nt with other elements of the Clean Air Act that apply planning require ments to areas as a whole. Addressing areas as a whole also provides a more logical outcome to the designation process in cases like this: where, as here, the area does not warrant a nonattain ment designation because the area cannot be classified as violating the standard, and the area does not warrant an attainment designation because the area cannot be classi fied as attaining the standard, the area clearly warrants a designation that the area “can not be classified on the basis of available information as meeting or not meeting” the standard.

Nothing in the Clean Air Act suggests either that the EPA should designate separate portions of the Chicago area separately or th at the provisions of 107 should be interpreted as yielding a large area if the ar ea is violating the standard but a small area if the area is attaining the standard or if the area is unclassifiable. To the contrary, once a nonattainment area is defined, the planning prov isions apply to the nonattainment area as a whole, wherein the planning addresse s a unified area that includes all the interconnected locations within an area that are experienci ng violations and contributing to those violations. The commenter evidently envisions balkanizing these areas into an unlimited number of separate pieces, with each piece designated without regard to the interconnections between these pi eces, but this approach is in consistent with the use of the word “area” and the planning process prov ided in the Clean Air Act. Similarly, the provisions for redesignating nonatta inment areas (“or portions th ereof”) to attainment are contingent on satisfaction of various prerequisites, where th e relevant provisions must address air quality across the entire area. For example, the EPA cannot redesignate a portion of a nonattainment area if permanen t and enforceable measures are yielding attainment in only a portion of the area. By the same logic, Section 107(d)(1) must be interpreted to provide for an attainment designa tion only if the entire area is attaining the standard and to provide for an unclassifia ble designation if the full area cannot be determined to be violating or attaining the standard.

The commenter highlights the absence of refere nce to contributing area in the criteria for an unclassifiable designation. However, this has significance only with the commenter’s use of the word “area.” Inte rpreting “area” to mean just one of several interconnected locations, and accepting the commenter’s inte rpretation that areas contributing to a potentially contributing to violations cannot be designa ted unclassifiable unless air quality is uncertain in those particular locations , yields the illogical re sult that the size of unclassifiable areas would genera lly be much smaller than the size of the area if it were designated nonattainment. In contrast, interpreting “area” to mean all of the locations that collectively influence whether the collectiv e set of locations meets the air quality standard yields a more coherent interpre tation of the three de signations in Section 107(d)(1) that is more consistent with the terminology and planning requirements elsewhere in the Clean Air Ac t that result from these desi gnations. With this broader interpretation of the word “area,” Section 107(d)(1)(i) clar ifies that nonattainment areasResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 35 of 68 must include contributing locations as well as violating locations, Section 107(d)(1)(ii) clarifies that locations that are meeting the st andard but are part of a broader area that is violating the standard cannot be designated attainment, and Section 107(d)(1)(iii) specifies that any area (which in context w ould include all the inte rconnected source and receptor locations) that cannot be determined to be violating or at taining the standard would be designated unclassifiable. The EPA believes that Lake and Porter Counties contribute to concentrations in Cook County and elsewhere in the Chicago area, and the EPA believes more generally that the set of locations with source-receptor relationships that warrant being included in the area th at could be called th e Chicago area would include Lake and Porter Counties. Since the EP A is unable to determine whether this area meets or does not meet the standard, the EPA be lieves that Section 107 (d)(1) provides for the Chicago area, including Lake and Porter Counties, to be designa ted as unclassifiable.

Comment: The EPA may not invalidate data for one purpose and rely on it for another. The EPA suggests that “ the available air qualit y data suggest that th e spatial distribution of exposure to PM 2.5 is similar to the distri bution the EPA found in 2005 , w hen it promulgated the Chicago 1997 PM 2.5 nonattainment area. ” However , the EPA alread y determined that the “ a v ailable air quality data ” in Illinois is invalid. The EPA ma y not
in v alidate data for designating Illinois countie s and at the same time arbitraril y u s e that invalid data as the basi s for designating Indiana ' s counties. Once the EPA determined that the Illinois data was in v alid

, that data could no longer be considered. It would be arbitrary for the EPA to second-guess Indiana ' s detailed and carefull y considered recommendation based on data the EP A has already deemed unreliable.

EPA Response: The commenter is misreading the EPA’s statements regarding the available air quality data. The EPA’s techni cal support document for its intended actions for Illinois and associated areas stated, “W hile the Illinois air quality data are not sufficiently complete to provide a reliable i ndication of the magnitude of concentrations, the available air quality data suggest that the spatial distribution of exposure to PM 2.5 is similar to the distribu tion the EPA found in 2005.” Thus, as is clear from the technical support document, the EPA believes that insuffi cient air quality data are available to determine whether a violation exists at any s ite in Illinois, but the EPA believes that sufficient air quality data are available to a ssess the spatial distribution of concentrations in the Chicago area. (Indeed, the EPA makes these data available for purposes such as these under parameter code 88501 in its Air Qu ality Subsystem (AQS).) Furthermore, even if the EPA were to disregard recent air qua lity data, the similarity of the distribution of emissions in 2002 (as examined in 2005) and in 2011 (examined more recently) lend further support to the view that the distributi on of concentrations recently is similar to the distribution in 2002 to 2004. As a result, and gi ven that “a review of the distribution of emissions, population, and vehicle travel also shows a similar distri bution” in the older and newer data sets, the EPA continues to belie ve that the same locations are contributing to high annual average concentrations now th at contributed to hi gh concentrations in 2002 to 2004. While the EPA has insufficient in formation to determine whether the high concentrations are above or below the sta ndard, the EPA has sufficient information to identify the range of locations that may be considered either to be experiencingResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 36 of 68 concentrations potentially above the standard or to be contri buting to these concentrations potentially above the standard.

Comment: One commenter notes that the EPA's proposed designation of Lake and Porter Counties as "unc lassifiable" is arbitrary and capricious. The EPA ' s sole basis for designating Lake and Porter counties as “ unclassifiable ” is theory that “ if the Chicago area is violating the NAAQS

, the area that the EPA finds would likely be contributing to that violation would likely be the same area as the EPA found in 2005 to contribute to violations of the 1997 PM 2.5 NAAQS [which includes Lake and Porter counties].” That speculation is unsupported by any facts in the reco rd and ignores the fact (noted in Table 2 of the Illinois TSD) that the western most Lake County PM 2.5 monitor (site number 18- 089-2010), which is less than five-thousand feet from the Illinois and Indiana border, had
PM 2.5 design values of 11.0 and 10

. 6 μ g/m 3 during 2010-201 2 and 2011-2013

, respectivel y. These values are w ell under the PM 2.5 NAAQS of 12 μ g/m 3 . The EPA has failed to demonstrate that current at tainment levels in Lake and Porter counties are linked to any non-attaining monitor.

The EPA may not rely on a 2005 NAAQS analys is when updated guidance and data are available. The EPA ' s claim that “ a review of the dist ribution of emissions

, population

, and vehicle travel also shows a s imilar distribution of th ese parameters [to 2005]” similarly fails to support an unclassifiable designation for L ake and Porter counties. Stating conclusively that some characteristi cs in the region appear similar to those in
2005

, without providing any citations or support

, falls far short of demonstrating that Lake and Porter counties are responsible for unidentified pot ential air quality problems in Illinois. First

, the current “ distribution of emissions ” cannot be determined without valid monitoring data in Illinois. Second

, having similar population and vehicle travel profiles in 2014 and 2005 does not demonstrate that Lake and Porter counties are “ likely ” contributing to a potential NAAQS violation in Illinois. That is particularly true because no specific Illinois monitor exists that would allow the EPA to evaluate such links. In addition

, the EPA ' s proposed designations fail to a ddress how the factors relied on in 2005 relate to U.S. EPA ' s 2013 guidance on Area Designations for the 2012 Revised Annual Fine Particle National Ambient Air Quality Standard ( " 2013 Guidance " ). The 2013 Guidance includes factors such as air quality data

, location of sources , growth rate and patterns

, weather

, geography and jurisdictional boundaries

, none of which are addressed in the Illinois TSD. The EPA has made no mention of whether these other factors are comparable to 2005

, and indeed has done no analysis whatsoever to determine the present-da y impacts of Lake and Porter counties on Cook County

, Illinois. In fact , the
EPA ' s assumptions fail to take into account important developments affecting the concentration and distribution of PM 2.5 in this region, such as the closing of the massive coal-fired State Line Generating Plan t in 2012 and the continual decrease in PM 2.5 ambient concentrations since 2009. The EPA cannot ignore such developments. The EPA is required to demonstrate a rational conn ection between the fact s found and the choices made when making NAAQS determinations. The EPA has not analyzed the actual relationship between emissions in Lake and Porter counties and PM 2.5 concentrations in Illinois, nor has the EPA even identified a NAAQS violation in Illinois that would

warrant such an inquiry. Basing designa tions on unfounded speculation over whatResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 37 of 68 impacts Lake and Porter counties might have on a potential NAAQS issue in Illinois when those counties specifically show attainment would result in an arbitrary and capricious designation.

EPA Response: The EPA’s technical support document for its PM 2.5 designations for Illinois and associated areas provides the EPA’s rationale for defining the Chicago area for purposes of these designations. The commen ter is incorrect in claiming that the EPA has not analyzed the relationship between em issions in Lake and Porter Counties and
PM 2.5 concentrations in Illinois and in claiming that the EPA’s designation is based on “unfounded speculation.” Neverthele ss, in alleging the absence of the information that is provided in the docket for the proposed rulemaking, the commenter mostly chooses not to provide comments on the merits of the analysis the EPA did provide and fails to identify objections to the specific elements of the analysis that the EPA did conduct.

The commenter objects to the approach of defining an unclassifiable area based on hypothesizing a violation and reviewing the lo cations that would contribute to such a violation, but the commenter does not suggest any alternative appro ach for defining the contributing portions of an ar ea that might violate the sta ndard or express views on how the EPA might better determine the boundaries of an area with the pot ential to violate the standard, including the associated locations that contribute to concentrations where the standard may be violated. (Comments interp reting Clean Air Act Section 107 to provide for the exclusion of contributing areas from areas designated unclass ifiable are addressed above.) The EPA continues to believe that we have properly designa ted as unclassifiable both the locations with the potential for viol ating the standard and the locations that contribute to concentrations wh ere violations may be occurring, and the EPA continues to believe that the most appropriate means of defining the contributing portions of such areas is to examine available information, in cluding information on air quality, emissions, meteorology, jurisdictional considerations, a nd topography, to determ ine what locations might be expected to contribute to the vi olations if in fact they are occurring.

The commenter asserts that the EPA’s conclusi on ignores the existen ce of data in Lake County, less than a mile from Cook County, s howing concentrations somewhat below the standard. The commenter does not explain his concept of linking monitoring data, and the commenter provides no explanation as to why concentrations at a bout 90 percent of the standard should be treated as evidence that Lake and Porter Counties do not contribute to concentrations in Cook County that may exceed the standard. The EPA need not identify a specific monitor in Cook County as violating th e standard to conclude that if a monitor in Cook County is violating the standard, La ke and Porter Counties are contributing to the violation.

The commenter questions whether the analysis that the EPA completed in 2005 addresses the criteria that the EPA identified in its 2013 guidance. In fact, though the 2013 guidance uses a different organization of its recommended factors than the 2003 guidance used in preparing the 2005 designations, the underlying in formation and analytical approaches recommended in the 2013 guidance are very similar to those recommended in the 2003 guidance. Thus, the analyses completed in 2005 effectively address the factors identified in the 2013 guidance. In additi on, the EPA reviewed more recent data,Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 38 of 68 concluding that these data (reviewed in accord ance with the 2013 gui dance) justified the same area definition as th e EPA promulgated in 2005.

Although the relevant recent da ta are available in the doc ket, for convenience the key relevant data are repeated he re, organized according to the factors identified in the 2013 guidance. As will be discussed below, the EPA finds that these data support the same boundaries of the Chicago area as the EPA promulgated in 2005.

Factor 1, Air quality: Although the data are insu fficient to provide an adequately reliable indication of whether the air quality standards are being violated in the Chicago area, the data indicate that the highest concentrations are observed in Cook County. Therefore, the greatest potential for violations exists in Cook C ounty, and the EPA may reasonably promulgate an unclassifiable area that id entifies a planning area that includes Cook County and the area around Cook C ounty that contributes to PM 2.5 concentrations in Cook County, so long as this area also incl udes the Chicago area locations with the potential to violate the standard.

The EPA agrees as a general matter that air quality has been improving in much of the Midwest, but that does not mean that Lake and Porter Counties ar e not contri buting to any violation that may be occurring elsewhere in the Chicago area.

Factor 2, Emissions: For this factor, th e EPA reviewed data from the 2011 National Emissions Inventory (NEI) version 1 (see http://www.epa.gov/ttn/chief /net/2011inventory.html ). For each county in the area of analysis, the EPA examined the magnitude of county-le vel emissions reported in the NEI. These county-level emissions represent the su m of emissions from the following general source categories: point sour ces, non-point (i.e., area) s ources, nonroad mobile, on-road mobile, and fires. The EPA also looked at the geographic distri bution of major point sources of the relevant pollutants. 1 Significant emissions levels from sources in a nearby area indicate the potential fo r the area to contribute to monitored violations.

To further analyze area emissions data, the EPA also developed a summary of direct
PM 2.5 , components of direct PM 2.5 , and precursor pollutants, which is available at http://www.epa.gov/pmdesignations/2012st andards/docs/nei2011v1pointnei2008v3count y.xlsx

. Evaluating the components of direct PM 2.5 and precursor gases can help identify specific sources or source types contributing to elevat ed concentrations at violating monitoring sites and thus assist in id entifying appropriate area boundari es. In general, directly emitted particulate organic carbon (POC) and VOCs 2 contribute to PM 2.5 organic mass

1 For purposes of this designations effort, “major ” point sources are those whose sum of PM precursor emissions (PM 2.5 + NOx + SO 2 + VOC + NH 3 ) are greater than 500 tons per year based on NEI 2011v1.

2 As previously mentioned, nearby VOCs are presumed to be a less important contributor to PM 2.5 OM than

POC.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 39 of 68 (OM); directly emitted EC contributes to PM 2.5 EC; NO X , NH 3 and directly emitted nitrate contribute to PM 2.5 nitrate mass; SO 2 , NH 3 and directly emitted sulfate contribute
to PM 2.5 sulfate mass; and directly emitted crustal material and metal oxides contribute to
PM 2.5 crustal matter. 3,4 The EPA believes that the quantitie s of those nearby emissions as potential contributors to the PM 2.5 violating monitors are somewhat proportional to the
PM 2.5 chemical constituents in the estimated urban increment. Thus, directly emitted POC is more important per ton than SO 2 , partially because POC emissions are already PM 2.5 whereas SO 2 must convert to PM 2.5 and not all of the emitted SO 2 undergoes this conversion.

This review of emissions information addr esses annual emissions rather than seasonal emissions for several reasons. First, emissi ons of significant pollutants are relatively constant throughout the year, so that there ar e insufficient seasonal emission variations to warrant a season-by-season review. Second, as noted above, except for the seasonal variations in nitrate concentr ations, the composition of the ur ban increment appears to be relatively constant throughout the year. The cold month con centrations of nitrate are linked to cold month emissions of NOx, but warm month emissions of NOx are also significant due to their contri bution to the photochemical reac tions that form secondary particulate matter. For these reasons, the EP A analyzed annual emissions and concluded that analysis of seasonal emissions was unnecessary.

Table 1 provides a county-level emissions su mmary (i.e., the sum of emissions from the following general source categories: point s ources, non-point (i.e., area) sources, nonroad mobile, on-road mobile, and fires) of directly emitted PM 2.5 and precursor species for the county with the violating monitoring site and nearby counties considered for inclusion in the Chicago area. Table 2 summarizes the directly emitted components of PM 2.5 for the same counties in the area of analysis for the Chicago area.

Table 1. County-Level Emissi ons of Directly Emitted PM 2.5 and Precursors (tons/year) County NH3 NOX PM 2.5 SO2 VOC Cook Co, IL 3307 108980 14387 16883 87924 Lake Co, IN 976 37838 6539 24464 16249 Will Co, IL 1694 28003 5646 34592 14309 Du Page Co, IL 751 23194 2731 566 19215 Lake Co, IL 623 20107 3197 10747 19148 Porter Co, IN 2852 17222 3737 16745 6283

3 See , Seinfeld J. H. and Pandis S. N. (2006) Atmospheric Chemistry and Physics: From Air Pollution to Climate Change , 2nd edition, J. Wiley, New York. See also, Seinfeld J. H. and Pandis S. N. (1998) Atmospheric Chemistry and Physics: From Air Pollution to Climate Change , 1st edition, J. Wiley, New

York.

4 USEPA Report (2004), The Particle Pollution Re port: Current Understanding of Air Quality and Emissions through 2003, found at: http://www.epa.gov/airtrends/aqtrnd04/pm.html

.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 40 of 68 Kane Co, IL 994 11808 2068 290 9761 Jasper Co, IN 2955 9960 2041 19513 2872 La Porte Co, IN 1832 8069 1945 13419 5016 La Salle Co, IL 1895 7680 2932 713 5024 Mc Henry Co, IL 1116 6605 1494 130 5845 Kenosha Co, WI 1228 6493 1197 1029 4249 Kankakee Co, IL 1315 4325 1777 163 3859 Grundy Co, IL 688 3780 1158 157 2263 Kendall Co, IL 745 3065 964 56 3191

Key:
NH3 – Ammonia

NO X – Nitrogen Oxides PM2.5 – Directly emitted PM 2.5 SO2 – Sulfur Dioxide VOC – Volatile Organic Compounds

Table 2 breaks down the direct PM 2.5 emissions value from Table 1 into their components. Table 2 summarizes the directly emitted components of PM 2.5 for the same counties in the area of analys is for the Chicago area.

Table 2. County-Level Emissions for Co mponents of Directly Emitted PM 2.5 (tons/year) 5
County, State POM EC PSO4 PN O3 Crustal Residual Direct Cook Co, IL 4538 2695 447 51 2675 3982 14387 Lake Co, IN 1343 763 771 32 1488 2143 6539 Will Co, IL 1033 665 339 14 1548 2047 5646 Du Page Co, IL 1178 658 55 11 326 503 2731 Lake Co, IL 982 498 108 10 669 931 3197 Porter Co, IN 792 610 218 26 954 1137 3737 Kane Co, IL 682 380 32 7 463 504 2068 Jasper Co, IN 284 110 90 2 732 824 2041 La Porte Co, IN 511 207 60 3 553 611 1945 La Salle Co, IL 551 198 112 6 1101 964 2932 Mc Henry Co, IL 456 222 19 4 399 394 1494

5 Data are based on the 2011 and 2018 Emissions Modeling Platform Data Files and Summaries ( ftp://ftp.epa.gov/EmisInventory/2011v6/v1platform ) available at: http://www.epa.gov/ttn/chief/emch/index.html#2011 (accessed 02/26/14).Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 41 of 68 Kenosha Co, WI 622 130 26 2 190 226 1196 Kankakee Co, IL 446 141 16 3 660 511 1777 Grundy Co, IL 231 115 27 3 376 406 1158 Kendall Co, IL 219 108 12 3 329 293 964

Key: PNO3 – Primary Nitrate PSO4 – Primary Sulfate

EC – Elemental Carbon POM – Primary Organic Matter

Crustal – Crustal Material

Using the previously described relationship between directly emitted and precursor gases and the measured mass to evaluate data pres ented in Tables 1 and 2, the EPA identified the following components warranting additiona l review: directly emitted organic matter, elemental carbon, NOx, and SO 2 . The EPA then looked at the contribution of these

constituents of interest from each of the c ounties included in the area of analysis as

shown in Tables 3a-d.

Table 3a. County-Level Particulate Or ganic Matter Emissions (tons/year)

State County POM % of Area Cum % Illinois Cook, IL 4538 33% 33% Indiana Lake, IN 1343 10% 42% Illinois DuPage, IL 1178 8% 51% Indiana Will, IL 1033 7% 58% Illinois Lake, IL 982 7% 65% Illinois Porter, IN 792 6% 71% Illinois Kane, IL 682 5% 76%
Wisconsin Kenosha Co 622 4% 81% Illinois LaSalle, IL 551 4% 85% Indiana La Porte, IN 511 4% 88% Indiana McHenry, IL 456 3% 91% Illinois Kankakee, IL 446 3% 95% Illinois Jasper, IN 284 2% 97% Illinois Grundy, IL 231 2% 98% Illinois Kendall, IL 219 2% 100%Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 42 of 68 Table 3b. County-Level Elemental Carbon Emissions (tons/year)
County EC % of Area Cum % Cook, IL 2695 36% 36% Lake, IN 763 10% 46% Will, IL 665 9% 55% DuPage, IL 658 9% 64% Porter, IN 610 8% 72% Lake, IL 498 7% 79% Kane, IL 380 5% 84% McHenry, IL 222 3% 87% La Porte, IN 207 3% 89% LaSalle, IL 198 3% 92% Kankakee, IL 141 2% 94% Kenosha, WI 130 2% 96% Grundy, IL 115 2% 97% Jasper, IN 110 1% 99% Kendall, IL 108 1% 100%

Table 3c. County-Level Nitrogen Oxides Emissions (tons/year)
County NO X % of Area Cum % Cook, IL 108980 37% 37% Lake, IN 37838 13% 49% Will, IL 28003 9% 59% DuPage, IL 23194 8% 67% Lake, IL 20107 7% 73% Porter, IN 17222 6% 79% Kane, IL 11808 4% 83% Jasper, IN 9960 3% 87% La Porte, IN 8069 3% 89% LaSalle, IL 7680 3% 92% McHenry, IL 6605 2% 94% Kenosha, WI 6493 2% 96% Kankakee, IL 4325 1% 98% Grundy, IL 3780 1% 99% Kendall, IL 3065 1% 100%

Table 3d. County-Level Sulfur Dioxide Emissions (tons/year)
County SO2 % of Area Cum % Will, IL 34592 25% 25% Lake, IN 24464 18% 42% Jasper, IN 19513 14% 56% Cook, IL 16883 12% 68%Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 43 of 68 Porter, IN 16745 12% 80% La Porte, IN 13419 10% 90% Lake, IL 10747 8% 98% Kenosha, WI 1029 1% 99% LaSalle, IL 713 1% 99% DuPage, IL 566 0% 99% Kane, IL 290 0% 100% Kankakee, IL 163 0% 100% Grundy, IL 157 0% 100% McHenry, IL 130 0% 100% Kendall, IL 56 0% 100%

In addition to reviewing c ounty-wide emissions of PM 2.5 and PM 2.5 precursors in the area of analysis, the EPA also reviewed emissions from major point s ources located in the area of analysis. The magnitude and locat ion of these sources can help inform nonattainment boundaries. Table 4 provides f acility-level emissions of direct PM 2.5 , components of direct PM 2.5 , and precursor pollutants (given in tons per year) from major point sources located in the ar ea of analysis for the Chicago area. Table 4 also shows the distance from the facility to the DV monitor for the area.

Table 4. NEI 2011 v1 Point Source Emissions (tons/year)

County Facility Name Distance

to Monitor

(mi) NH3 NOx PM 2.5 SO2 VOC Total

Cook, IL Corn Products International Inc (031012ABI) 13 1 665 463 1,569 511 3,208

Cook, IL Fisk Electric Generating Station (031600AMI) 14 0 1,098 199 4,133 1 5,432

Cook, IL OHare Airport (ORD) 2 5,261 139 578 961 6,939

Cook, IL Midway Airport (MDW) 14 1,150 22 133 195 1,499

Cook, IL Ford Motor Co (031600AAR) 26 1 18 27 0 650 696

Cook, IL Saint-Gobain Containers Inc (031069AAI) 26 1 412 78 158 21 670

Cook, IL Crawford Electric Generating Station (031600AIN) 12 0 1,893 281 6,545 1 8,721

Cook, IL Koppers Inc (031300AAJ) 12 1 115 4 857 106 1,083

Grundy, IL Equistar Chemicals LP (063800AAC) 45 0 549 178 19 454 1,200Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 44 of 68 County Facility Name Distance

to Monitor

(mi) NH3 NOx PM 2.5 SO2 VOC Total

Kankakee,
IL Natural Gas Pipeline Co of America (091811AAB) 65 0 495 10 0 32 537

Lake, IL Waukegan Electric Generating Station (097190AAC) 29 1 2,563 718 9,931 2 13,214

La Salle, IL Pilkington North America (099825AAG) 68 0 625 107 303 10 1,045

La Salle, IL Owens-Brockway Glass Container Inc (099490AAD) 76 0 308 65 138 22 533

La Salle, IL Illinois Cement Co (099030AAZ) 76 3 897 32 89 32 1,052

Will, IL Oxbow Midwest Calcining LLC (197803AAK) 23 145 130 7,003 0 7,278

Will, IL Exxon Mobil Oil Corp (197800AAA) 41 207 1,720 249 1,317 429 3,922

Will, IL Midwest Generation LLC (197809AAO) 35 1 6,314 1,391 17,034 5 24,745

Will, IL Will County Electric Generating Station (197810AAK) 25 1 2,227 392 8,301 2 10,922

Will, IL CITGO Petroleum Corp (197090AAI) 24 232 685 144 513 443 2,017

Jasper, IN NIPSCO - R.M. SCHAHFER (00008) 68 1 7,367 747 19,352 161 27,627

Lake, IN STATE LINE ENERGY LLC (00210) 26 1 7,005 412 8,044 83 15,544

Lake, IN Indiana Harbor East (00316) 31 19 4,813 526 2,874 1,123 9,355

Lake, IN MITTAL STEEL (ISG INDIANA HARBOR WEST) (00318) 31 14 1,601 711 860 84 3,270

Lake, IN COKENERGY INC. (00383) 31 85 4,892 4,977

Lake, IN BP PRODUCTS NORTH AMERICA, WHITING R (00003) 29 17 2,548 427 697 2,118 5,806

Lake, IN ANR PIPELINE NAT GAS_CO ST. JOHN STATION (00069) 42 482 12 0 26 520

Lake, IN INDIANA HARBOR COKE (00382) 31 17 859 154 1,898 2 2,930

Lake, IN U S STEEL CO GARY WORKS (00121) 38 103 4,313 1,529 4,202 1,168 11,315

Lake, IN CARMEUSE LIME INC (00112) 33 1,688 31 313 13 2,045Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 45 of 68 County Facility Name Distance

to Monitor

(mi) NH3 NOx PM 2.5 SO2 VOC Total

La Porte, IN NIPSCO - MICHIGAN CITY (00021) 53 24 1,433 388 13,353 88 15,287

Porter, IN ArcelorMittal Burns Harbor (00001) 44 29 8,289 2,065 13,843 497 24,723

Porter, IN NIPSCO - BAILLY STATION (00002) 45 20 1,975 187 2,560 67 4,809

Kenosha,
WI Wisconsin Electric Power Pleasant Prairie Power Plant (230006260) 40 636 2,498 130 928 124 4,316

The commenter observes that the State Line plant shut down in 2012. Although the commenter has not provided evidence as to whether this shutdown is permanent or enforceable, the EPA has reviewed this inform ation. The EPA notes that other facilities (such as the ArcelorMittal Burns Harbor faci lity) in Lake and Porter Counties have greater emissions, and the EPA concludes that emissions even with that plant shutdown are sufficient to conclude that Lake and Po rter Counties are a cont ributing portion of the Chicago area.

The EPA also evaluated the population and vehi cle use characteristics and trends of the area as indicators of the probable location a nd magnitude of non-point source emissions. Rapid population growth in a county on th e urban perimeter signifies increasing integration with the core urban area, and indi cates that it may be appropriate to include the county associated with area source a nd mobile source emissions as part of the nonattainment area. Table 5 shows th e 2000 and 2010 population, population growth since 2000, and population density for each county in the area.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 46 of 68 Table 5. Population Growth and Population Density.

County Population
2000 Population
2010 % Change
from
2000 Land Area (Sq. Miles) Population Density (per Sq.

Mile) % of
Area Cumulative
%

Cook, IL 5,376,741 5,199,377 -3.3% 946 5,498 54% 54%

DuPage, IL 904,161 918,186 1.6% 334 2,752 9% 63%

Lake, IL 644,356 704,303 9.3% 448 1,574 7% 70%

Will, IL 502,266 678,883 35.2% 837 811 7% 77%

Kane, IL 404,119 516,034 27.7% 520 992 5% 83%

Lake, IN 484,564 496,112 2.4% 497 998 5% 88%

McHenry, IL 260,077 309,223 18.9% 604 512 3% 91%

Kenosha, WI 149,577 166,632 11.4% 273 611 2% 93%

Porter, IN 146,798 164,565 12.1% 418 394 2% 94%

Kendall, IL 54,544 115,257 111.3% 321 360 1% 96%

La Salle, IL 111,509 113,816 2.1% 1,135 100 1% 97%

Kankakee, IL 103,833 113,502 9.3% 677 168 1% 98%

LaPorte, IN 110,106 111,432 1.2% 598 186 1% 99%

Grundy, IL 37,535 50,103 33.5% 420 119 1% 100%

Jasper, IN 30,043 33,531 11.6% 560 60 0% 100% Source: U.S. Census Bureau population estimates for 2000 and 2010

Table 6. 2011 VMT for the Chicago Area

. 2011 VMT % of Area Cum. % County Total

Cook, IL 31,705,270,056 45% 45%

DuPage, IL 8,059,051,190 11% 57%

Will, IL 5,518,889,913 8% 64%Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 47 of 68 2011 VMT % of Area Cum. % County Total

Lake, IL 5,436,289,715 8% 72%

Lake, IN 4,664,891,193 7% 79%

Kane, IL 3,547,189,906 5% 84%

McHenry, IL 2,106,689,997 3% 87%

Porter, IN 1,836,723,893 3% 89%

La Porte, IN 1,702,002,112 2% 92%

La Salle, IL 1,333,020,018 2% 94%

Kenosha, WI 1,313,367,247 2% 96%

Kankakee, IL 969,019,995 1% 97%

Kendall, IL 768,299,498 1% 98%

Jasper, IN 710,369,578 1% 99%

Grundy, IL 693,739,990 1% 100%

70,364,814,301

Factor 3: Meteorology The EPA evaluated available meteorologica l data to determine how meteorological conditions, including, but not limited to, weat her, transport patterns, and stagnation conditions, could affect the fate and transpor t of directly emitted particulate matter and precursor emissions from sources in the ar ea of analysis. The EPA used two primary tools for this assessment: wind roses and kernel density estimation (KDE). When considered in combination with area PM 2.5 composition and county-level and facility emissions source location information, wind ro ses and KDE can help to identify nearby areas contributing to violations at violating monitoring sites.

Wind roses are graphic illustra tions of the frequency of wind direction and wind speed. Wind direction can indicate the directi on from which contributing emissions are transported; wind speed can indicate the for ce of the wind and thus the distance from which those emissions are transported. Th e EPA constructed wind roses from hourlyResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 48 of 68 observations of wind direc tion and wind speed using 2009- 2012 data from National Weather Service locations archived at the National Climate Data Center. 6 When developing these wind roses, the EPA also used wind observations collected at meteorological sampling stations collocated at air quality monitoring sites, where these data were available. Figure 1 shows wind roses that the EPA generated from data relevant in the Chicago area.

As shown in Figure 1, while winds from the we st and south are somewhat more frequent than winds from other directions, all directi ons have sufficient frequency of winds that emissions in all directions may be considered to contribute to viola tions at the violating monitor.

6 ftp.ncdc.noaa.gov/pub/data/noaa or http://gis.ncdc.noaa.gov/map/viewer/#app= cdo&cfg=cdo&theme=hourly&layers=1&node=gis Quality

assurance of the National Weather Service data is described here: http://www1.ncdc.noaa.gov/pub/data/inventories/ish-qc.pdf Figure 1. Wind Roses in the Chicago AreaResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 49 of 68 Factor 4: Geography/topography

To evaluate the geography/t opography factor, the EPA assesse d physical features of the area of analysis that might define the ai rshed and thus affect the formation and distribution of PM 2.5 concentrations over the area. Th e Chicago area does not have any geographical or topographical barr iers significantly limiting ai r pollution transport within its airshed. Therefore, this factor did not play a significant role in this evaluation.

Factor 5: Jurisdictional boundaries

In defining the boundaries of the intende d Chicago nonattainment area, the EPA considered existing jurisdictional boundaries , which can provide eas ily identifiable and recognized boundaries for purposes of impl ementing the NAAQS. Existing jurisdictional boundaries often signify well rec ognized boundaries that the st ate can easily administer and for which the state has the necessary legal authority for carrying out air quality planning and enforcement functions. Examples of such jurisdictiona l boundaries include existing/prior nonattainment area boundaries for particulate matter, county lines, air district boundaries, township boundaries, areas covered by a metropolitan planning organization, state lines, and Reservati on boundaries, if applicable. Where existing jurisdictional boundaries were not adequate or appropriate to describe the nonattainment area, the EPA considered other clearly defi ned and permanent landmarks or geographic coordinates for purposes of id entifying the boundaries of th e intended designated areas.

The Chicago area was previously designa ted nonattainment for the 1997 annual PM 2.5 NAAQS. The EPA’s intended nonattainment area for the 2012 NAAQS is identical to area that was designated nonattainment for the 1997 NAAQS. Furthe rmore, the Illinois portion of the EPA’s intended nonattainmen t area matches the identical Illinois recommendations with respect to both the 2012 NAAQS and the 1997 NAAQS. On the other hand, the area within I ndiana that the EPA designate d nonattainment for the 1997 standard exceeded Indiana’s recommendation for that standard (by including Porter County in addition to Lake County) and differs by two counties from Indiana’s recommendation that the nonattainment area for the 2012 NAAQS include no area within Indiana.

Recent Chicago nonattai nment areas for PM 2.5 and for ozone have included the two townships in Grundy County and the one township in Kendall County that are included in the EPA’s intended 2012 PM 2.5 NAAQS nonattainment area. Townships are well established and well recognized jurisdictional boundari es in Illinois, and so the use of these county subdivisions as boundaries for th e nonattainment should provide for suitable ease of administration of nonattainment area requirements. These townships reflect the more urbanized portions of these otherwise re latively rural counties, and inclusion of these townships is consistent with Illinois’ recommendations and provides for a definition of the nonattainment area that is consistent with other nonattainm ent area boundaries for other NAAQS.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 50 of 68 This information demonstrates that a review of the most recent available information on the five factors identified in the 2013 guidance in accordance with that guidance supports defining the Chicago area as having the same boundaries as the EPA established in 2005.

Comment: We believe that while the EPA and Illinois the EPA (IEPA) work to determine the cause and extent of any invalid PM 2.5 data and appropriate remedies, there is sufficient technical evidence to suppor t the exclusion of Grundy County townships from the Chicago PM 2.5 nonattainment area. We ask that as you move forward with IEPA to clarify Illinois nonattainment boundari es, you exclude portions of Grundy County (specifically the townships of Aux Sable and Goose Lake) from consideration as part of the nonattainment area. Inclusion of countie s that do not materially contribute to nonattainment can have severe negative ec onomic consequences for that county. In addition to the potential of costly new regulat ions that do not improve air quality at the violating monitor, employers and manufactur ers evaluating areas consider an area's attainment/non-attainment classification befo re making decisions on expansions or new facilities.

In the case of Grundy County, IEPA's reco mmendation appears to have weighted meteorology, specifically prevai ling wind direction, over all ot her factors. IEPA and the EPA should now reexamine the data, weight monitored air quality data and emissionsrelated data more appropriately, and remove Grundy County from any further nonattainment classification discussion.

While the EPA has declared much if not all of IEPA's PM 2.5 data invalid for technical reasons having to do with data collection a nd processing, this does not necessarily mean that the data is wholly inaccura te. IEPA's data tracks region al levels and trends observed by the CASTNET monitors in Illinois. For th is reason, we believe that our earlier data analysis provided to IEPA in November 2013 is still approp riate to consider.

Due to its small population, limited urban ar ea, and moderate point source emissions potential, Grundy County is not required to have a PM 2.5 monitor located in the county. However, adjacent Will County, which is downwind of Grundy County particularly on days when the violating Chica go monitor experienced higher PM 2.5 levels, has two monitors. The annual average levels experi enced by these monitors can be used to understand whether high PM 2.5 levels are being emitted in Grundy County and making their way through transport to the violating monitor. The Jo liet monitor in Will County downwind of Grundy County shows an a nnual average concentration of 11 μ g/m 3 , which is below the new 12 μ g/m 3 NAAQS level. The Braidwood m onitor, located immediately adjacent to Grundy County, shows an a nnual average concentration of 9.9 μ g/m 3 . It should be noted that the Joliet monitor in W ill County is located in close proximity to a large electric generating unit, or EGU, whic h is much more likely to contribute to the annual average concentration at this monitor ra ther than the much smaller, more distant emissions from Grundy County. Both the Joli et and Braidwood monitors have shown improved air quality in recent years. In the three-year pe riod ending in 2009, the last period that the Joliet monitor exceeded the new NAAQS, its annual average was 12

μ g/m 3 . It has continued to show declining PM 2.5 concentrations, and as mentioned above,Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 51 of 68 most recently measured 11 μ g/m 3 . The Braidwood monitor last exceeded the NAAQS in the 3-year period ending in 2004. PM 2.5 concentrations have al so decreased at this monitor, from 10.4 μ g/m 3 in the three-year period ending in 2009 to 9.9 μ g/m 3 in the most recent 3-year period. This analysis dem onstrates suggests that the air flowing from Grundy County towards the Chicago re gion has some of the lowest PM 2.5 concentrations in the region. Furthermore, trends in PM 2.5 levels at these two cl osest monitors to Grundy County show decreasing amounts of PM 2.5 levels, which supports this assertion. Additionally, predicted concentrations of PM 2.5 for a portion of Grundy County, and several adjacent counties, represent some of the predicted lowest PM 2.5 concentration in the Midwest.

IEPA staff have over-relied on one factor—wi nd direction—in the fi ve factor analysis. The exceedance concentrations experienced by one monitor in the Chicago region do not have a significant contribution from emissions in a county like Grundy that is predicted to experience low PM 2.5 levels based on regional air quality monitors. Rather, they are much more likely to be emitted closer to the source of the sole exceeding monitor.

From the available air quality data, then, it does not appear that emissions from Grundy County, as they may make their way toward the violating monitor, contribute in any material way to high PM 2.5 levels at their closest monito rs. We recognize that a recent technical systems audit of IEPA 's monitoring program has invalidated much if not all of their recent PM 2.5 monitoring data. However, Illinoi s also has Clean Air Status and Trends Network (CASTNET) mon itors in Bondville (located near Champaign) and in Stockton (west of Chicago) which have indepe ndent analysis procedures, and which have not been invalidated. The Clean Air Status and Trends Network (CASTNET) is a national air quality monitoring network designed to pr ovide data to assess trends in air quality, atmospheric deposition, and ecological effects du e to changes in air pollutant emissions. CASTNET provides long-term monitoring of air qua lity in rural areas to determine trends in regional atmospheric nitrogen, sulfur, a nd ozone concentrations and deposition fluxes of sulfur and nitrogen pollutants in order to evaluate the effectiv eness of national and regional air pollution control programs. A re view of national CASTNET data indicates that significant reductions in SO 2 , SO 4 , HNO 3 , total NO 3 , and NH 4 have been realized in the Eastern US. For example, between 1990-1992 and 2010-2012, SO 2 concentrations were reduced from 8.9 μ g/m 3 to 2.1 μ g/m 3 , a 76% reduction. Theref ore, we believe that an analysis of CASTNET recent measurements and trends lends independent support to the IEPA data showing low predicted PM 2.5 emissions and precursors in rural areas such as Grundy County. Both Illinois CASTNET monitors demonstrate an observed downward trend (air quality improvement) in co mbined quarterly sulfate and nitrate from 2001 through 2013. This trend is consistent w ith average and maximum annual and 24-hr
PM 2.5 concentration trends seen in other monitoring networks. Emissions of PM 2.5 and its precursors and constituents from Grundy C ounty represents the lowest category of emissions of any of the counties being consider ed for inclusion in th e nonattainment area. In addition, according to 2011 NEI data, consistent with measured trends in constituent, precursor and PM 2.5 concentrations, emissions of key constituent and precursors of PM 2.5 , as well as direct emissions of PM 2.5 are lower in 2011 than in 2008, in some cases dramatically so.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 52 of 68 Emissions from key constituents, precursors and direct PM 2.5 have decreased significantly. A slight increase in SO 2 emissions is insignificant in the context of the total overall tons per year decreas e demonstrated by the other em issions categories and in context of the overall SO 2 emissions inventory for the proposed non-attainment area (Grundy County's SO 2 emissions account for approximately 0.08% of the nine-county total SO 2 emissions of 63,110.10 tpy). Furthermore, as IEPA notes in its designation recommendation, Grundy County contributes on ly 1.7% to the total emissions in the nine-county regions’ PM 2.5 total. This updated inform ation further supports our conclusion that emissions from Grundy Count y are an extremely small fraction of the total emissions in the proposed nonattainment area. The significant decreases in these emissions from 2008 to 2011 furthe r supports this conclusion.

In light of the decreasing emissions from 2008 to 2011, we contend the IEPA’s analyses of emission related factors do not support in clusion of Grundy County townships in a Chicago PM 2.5 nonattainment area. Emissions-relate d factors are intended to place context around the emissions data, such as wh ether an emissions category is expected to grow in the future. A strong pattern of gr owth in population, vehicle miles traveled, industrial expansion, or nonroad transit might bolster an ar gument that a county with relatively insignificant current emissions shoul d be included in a nonattainment area. In the case of Grundy County, analysis of emissi on-related factors do not make this case.

IEPA’s analysis first discusses population density. In the case of Grundy County, the 2010 population density was 119 people per sq uare mile. In Cook County, the county with the sole violating monito r, the population density is 5,491 persons per square mile. The 50,063 residents of Grundy County make up 0.05% of the region's total population, the smallest fraction of any county being cons idered for inclusion in the nonattainment area. By 2012, the Grundy County population de nsity increased by one person per square mile. By contrast, Cook County a dded 39 people per square mile.

The document then provides population growth projections between 2000 and 2030. While Grundy County is predicted to add between 10,000-50,000 persons over that time period, four other counties in the regi on are predicted to add over 200,000 persons each. Clearly population growth in the region will not be driven by projected new inhabitants of Grundy County.

The document then turns to VMT per county, and further breaks out the VMT for Aux Sable and Goose Lake townships. The combined VMT for those two townships represents 0.56% of that of Cook County, the county with the so le violating monitor. This comparison does not even include the VMT from the other counties being considered for inclusion in the region. Agai n, Grundy County has the smallest VMT of any county in the proposed nonattainment area. Grundy County doe s have a moderate percentage of its residents commuting out of the county for wor k. However, when one is dealing with the commuting habits of a county with 50,063 total inhabitants, the impact of their commute is dwarfed by the emissions and VMT of inha bitants of far more populous counties, such as Cook County, which has over 5 million resident s. Therefore, the relative weight one gives to commuting patterns for Grundy Count y, especially as emissions from motorResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 53 of 68 vehicles continues to decline as a result of federal fuel and engine standards, should be extremely small.

Wind roses and summary back trajectory data presented in the IEPA document show that on high PM 2.5 days, winds most frequently originat e in the South, South/South West, and South West sectors, which comprise Cook, Kankakee, Will and Grundy Counties. Interestingly, on the two days when the highest PM 2.5 concentrations were experienced at the violating monitor, daily back trajectorie s demonstrate that wind directions were not from this sector. IEPA makes a case that wi nds were from a sector that includes Grundy County townships during several high PM 2.5 days. However, it appears to weight that evidence far more strongly than it does the more compelling ambient air quality data and emissions and emissions related data. On some high PM 2.5 days, air parcels travel through Grundy County, and then through Will County and Cook County to reach the sole violating monitor some 50 miles downwind. Bu t all available eviden ce suggests that the air that is being transported from Gru ndy County on those days does not contain a significant amount of PM 2.5 , its constituents or precursors. Therefore, meteorology, when viewed in the appropriate cont ext with ambient air data and emissions data, should not be given the pre-eminent weight that it appare ntly has been given in this analysis.

Geography and topography are not expected to be key driv ers in the nonattainment boundary designation analysis.

Grundy County is not contained in the Chi cago Metropolitan Agen cy for Planning (CMAP). This organization is responsible fo r regional planning, in cluding transportation and environmental planning. It is the de signated Metropolitan Planning Organization (MPO) for the region, and is responsible for transportation planning to achieve transportation conformity with the State Implementation Plan. Grundy County's lack of inclusion in the organization charged with transportation, environmental planning, and the transportation conformity analysis create s a jurisdictional incompatibility that both highlights its lack of contribu tion of significant motor vehicl e emissions to the region's total, and its inability to pa rticipate in future transportation planning decisions in the region.

EPA Response: The EPA is designating the Chicago area as unclassifiable, not as nonattainment. Consequently, this designation w ill not create the “poten tial of costly new regulations” that the commenter fears, a nd the EPA presumes that a designation as unclassifiable does not significan tly alter “decisions on expansions or new facilities” as compared to designation as attainment/unclass ifiable. In any case, the EPA is presently obliged to determine boundaries of the Chica go area, an area that may or may not be violating the PM 2.5 standard, but if subsequent data s how the existence of violations of the standard, the EPA will conduct a new revi ew of the area that contributes to the violations that will not nece ssarily be the same as the area the EPA currently believes to represent the Chicago area. For that matter, the EPA is designating the entire State of Illinois as unclassifiable, so the EPA be lieves that Grundy County should be designated unclassifiable regardless of wh ether portions of the county are or are not judged to be part of the Chicago unclassifiable area.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 54 of 68 The commenter provides substantial useful information for evaluating the potential of Grundy County to contribute to violations of the PM 2.5 standard in the Chicago area. However, the EPA continues to believe that the relevant two townships in the county (Aux Sable and Goose Lake Townships) wa rrant being included in the Chicago unclassifiable area. Given th e regional nature of PM 2.5 concentrations, th e air quality in Grundy County and neighboring Will and Kankak ee Counties is not a good indicator of the potential of emissions elsewhere in the Ch icago area where violations are more likely occurring. The commenter acknowledges that wi nds are prone to carry emissions from Grundy County into Cook County and elsewhere in the Chicago area where the potential for violations of the PM 2.5 standard are greater, but the commenter argues that emissions in Grundy County are too low rela tive to emissions in other nearby counties to warrant including Grundy County as a contributing part of the Chicago area. The EPA acknowledges that the contributi ons of other nearby counties to potential violations in the Chicago area are likely to be greater than that of Grundy County, but the EPA believes that Grundy County has the potenti al for a sufficient impact on concentrations elsewhere in the area to warrant being designated as a contributing part of the Chicago unclassifiable area. The fact that Grundy County is not part of the Chicago Metropolitan Agency for Planning does not warrant excl uding Grundy County as a contributing portion of the Chicago area. Nevertheless, as noted above, if the Chicago area is subsequently determined to be violating the PM 2.5 standard, the EPA and Il linois will reassess the appropriate boundaries of the area, includi ng reassessing whether Grundy County should be designated as part of the area.

Comment: Indiana Department of Environmental Management (IDEM) believes that the certified, attaining 2011-2013 data collected by monitoring sites in Indiana’s monitoring network within Lake and Porter Counties, IN , should be sufficient to designate Lake and Porter Counties as “attainme nt” versus the intended “ unclassifiable” designation associated with the Chicago, IL area (inc luding Lake and Porter Counties, IN) as indicated in the EPA’s August 19, 2014 letter.

EPA Response: The EPA believes that areas designated as unclassifiable must include all locations that are contributi ng to concentrations that may be above the standard. The Chicago area may be violating the standard, and Lake and Port er Counties have sufficient emissions that are transporte d to relevant portions of th e Chicago area with sufficient frequency to warrant designating these tw o counties as contributing to potential violations. That is, the EPA is designati ng a Chicago unclassifiable area that includes both those portions of the area that may or may not be violating the standard and those portions of the area (including Lake and Porter Counties) that would reasonably be expected to be contributing to a violation if in fact a violation is occurring.

3.2.4. EPA Region VI

Comment: Sierra Club states that for the reasons outlined in their comment letter, including the allegedly capricious nature of the 2011-2013 time period for the design value, the problems with the state’s exceptional events requests, and the community based monitoring showing nona ttainment levels of PM 2.5 in certain HoustonResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 55 of 68 communities, the commenters respectfully oppose the designation of Houston as attainment and recommend a designation of nona ttainment. Sierra Club states that the levels of PM 2.5 in the Houston area during the 20 10-2012 three year period, and the dates evaluated by the State of Texas for its N ovember 26, 2013 recommendation letter to the EPA, indicate that people in Houston are br eathing unhealthy air. Despite the State’s evaluation of air quality and exceptional events issues during 2010-2012, and Sierra Club’s participation in that process and in particular th e issue of exceptional events, Sierra Club asserts the EPA has inappropriate ly proposed to change the basis for the decision to the 2011-2013 three year period. Sier ra Club states the selection of another three year period different than the one th at the State of Texas evaluated for its recommendation follows a recent pattern by th e EPA, and that the allegedly capricious nature of these kinds of changes is inappr opriate and leads to poor policy. Sierra Club explains the Clean Air Act describes a part icular process for de signation decisions and the EPA should not deviate from that proce ss in a capricious manner by selecting time periods to avoid nonattainment designations, and thus minimize its own workload or the workload of the states. Sierra Club stat es the nonattainment SIP process can bring important public health benefits in cities w ith poor air quality a nd avoiding workload or political pushback are poor reasons for sele cting time periods for evaluation. Sierra Club contends the EPA should not shift this time pe riod, or in the alte rnative, should allow another period of notice and comment to allow the public and the State to evaluate this new time period.

EPA Response: The EPA disagrees with the Sierra Club statement that using data from 2011 to 2013 is capricious in nature, is inappr opriate and leads to poor policy. As stated on page 3 of the EPA’s April 16, 2013 Memo randum from Gina McCarthy to Regional Administrators: “We expect that in provi ding designations recommendations to the EPA by December 13, 2013, states and tribes will al so review air quality data from 2010 to 2012. However, prior to EPA making final designations decisions, quality-assured, certified air quality monitoring data from 2013 may be available. If so, EPA’s final designations decisions will be based on data from 2011 to 2013.” This guidance memo was shared with the states and tribal gove rnments and other stakeholders and made available to the public. The EPA has followed this policy of relying on the most recently available certified data in numerous in itial area designations for multiple NAAQS, including most recently the area desi gnations for the 2008 ozone NAAQS. The EPA believes that it is important to base area designation decisions on the most recently available certified monitoring data sp ecifically for pollutants, such as PM 2.5 , where the emissions inventories are trending upward or downward, signaling the potential for 3- year design values to shift above or below the level of the NAAQS. In the case of the Houston area, the emissions of the precursor pollutants oxides of nitrogen and sulfur dioxide are declining, and we see these emi ssions trends reflected in the monitored ambient concentrations.

Comment: The commenters provided an extensive se t of concerns about the TCEQ’s use of exceptional events data exclusion requests

.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 56 of 68 EPA Response: The EPA based its intended and fina l area designation for the Houston area on certified and quality-assured monito ring data for the period from 2011 to 2013. The 3-year design value on which we ba sed our decision was calculated without excluding dates flagged as exceptional even ts. Therefore, the comment is moot.

Comment: The commenters questioned whether the monitoring data obtained at the Clinton Drive Monitor site is representa tive for the Galena Park community and submitted monitoring data gathered from five monitoring sites operated by Air Alliance Houston at various locations within the community (see Figure 2 below). The commenters believe the Air Alliance monitoring data demonstrated that the Clinton Drive monitor was not representative of area air quali ty and that the area c ould be in violation of the NAAQS.

EPA Response: We first note that we must consider all valid data within the relevant 3- year time frame that is collected in confor mance with the Federal Reference Methods and siting requirements in our de signation decision. As discusse d below, the Clinton Drive monitoring site meets these requirements and th erefore, must be considered. The location of the Clinton Drive monitor conforms to all a pplicable siting criteria, as set forth in 40 CFR Part 58, Appendix D and E, and has been approved by the EPA as part of TCEQ’s most recent Annual Monitoring Network Plan and 5-year Monitoring Network Assessment. The Clinton Drive monitor is ap proximately 1.5 miles from Galena Park, as shown in Figure 2. At Clinton Drive, TCEQ operates PM 2.5 Federal Reference Method (FRM) and non-FRM continuous monitors.

Figure 2. Clinton Drive and Galena Park Community Monitoring Sites

Note: Clinton Drive Monitor (Location A), and Galena Park Monitors (Locations B – F).Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 57 of 68 With regard to whether the data collected by Air Alliance Houston indicates a violation, Region 6 evaluated the monitoring data s ubmitted by the commenter. Approximately 29 discrete samples were collected in the Ga lena Park community over a 16-month period from May 2012 through September 2013, thus the da ta is limited in scope compared to the data collected by regulatory monitors ov er a 3-year period and subject to data completion criteria. Additionally, these data were also not monitored and collected according to the requirements of the federal reference method for PM 2.5 found in 40 CFR part 50, Appendix L. Our designations must be based on valid 3-year design values, and even if the monitoring data submitted by the commenters fully complied with the siting and data quality criteria, there are not suffici ent data on which to derive a valid, 3-year design value.

Therefore, these data do not affect our deci sion to designate the area as Unclassifiable/ Attainment.

3.2.5. EPA Region IX

Comment: Nevada Bureau of Air Quality Planni ng has received the EPA’s August 19, 2014, letter indicating the intend ed designation of unclassifiab le/attainment for the entire state of Nevada. Nevada agrees with this intended designation and requests that final designations subdivide the state according to hydrographic areas.

EPA Response: The EPA appreciates the commenters ’ support and is designating areas in Nevada based on hydrographic areas.

Comment: The California Air Resources Board (CA RB) appreciates the time, effort, and collaborative approach U.S. EPA staff took to identify the proposed nonattainment areas as well as surrounding areas that may contribut e to the high measured values. CARB also notes that the extensive an alysis contained in the pr eliminary Technical Support Document matches CARB’s recommendations for PM 2.5 nonattainment areas in the State and appropriately captures th e areas of high measured PM 2.5 and the surrounding areas from which emissions can contribute to th e high measured levels. CARB looks forward to continued collaboration with U.S. EPA in protecting public health for all Californians.

EPA Response: The EPA appreciates the commenters’ support.

Comment: The Pechanga Band of Luiseño Mission Indians submits a revised recommendation of “unclassifiable/attain ment” based on complete, certified 2011-2013 monitoring data that indicate that areas of Indian country are attaining the 2012 annual
PM 2.5 standard. The Tribe also requests cons ultation regarding final designations.

EPA Response: The EPA appreciates the updated and revised recommendation from the Pechanga tribe. The EPA’s preliminary review of monitoring data agrees with the Tribe’s conclusions and the EPA agrees with the Tribe’s revised recomme ndation to designateResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 58 of 68 their portion of Indian country as “unclassifiable/attainment” for the 2012 annual PM 2.5 standard.

Comment: The Soboba Band of Luiseño Indians requests consulta tion to address questions related to the technical analyses included in the preliminary California Technical Support Document that support inclusion of the Soboba Indian Reservation in the Los Angeles-South Coast Air Ba sin nonattainment area for the 2012 annual PM 2.5 standard.

EPA Response: The EPA welcomes the Soboba tribe’ s request for consultation and has initiated consultation with the tribe.

3.2.6. EPA Region X

Comment: The December 6, 2013, state recommendati on letter from Idaho Department of Environmental Quality (ID EQ) to the EPA Region 10 showed that according to the 2012 standards, the Pinehurst monitor had not exceeded the standard. In August 2014, the EPA Region Administrator Denni s McLerran sent a letter to Governor Otter stating that the EPA is proceeding with intended initia l area designations using quality-assured, certified air quality monitoring data from 2011-2013. The letter from the EPA further stated that after “extensive collaborative discussions with IDEQ, and consideration of other relevant technical information, including 2011-2013 air quality data and 2014 technical analyses, the EPA intends to de signate a partial area of Shoshone County (limited to areas surrounding the towns of Pi nehurst, Smelterville, and Kellogg) as nonattainment.”

The commenter believes that this lette r defied the Governor and IDEQ’s recommendations, did not specifically stat e what was collaborated upon, and used a 2014 technical analysis which has either not been finalized or is not available to the public.

EPA Response: The EPA and IDEQ have worked t ogether to review the data and develop the technical analys es in the West Silver Va lley (WSV) Technical Support Document (TSD). The EPA’s final 2012 Annual PM 2.5 NAAQS revision provided that, pursuant to section 107(d)(1) of the CAA, states were to submit initial designation recommendations by December 13, 2013 (78 FR 3086, 3250 Jan. 15, 2013). Such a designation recommendation would necessarily be based on air quality data from 2010- 2012 because data for 2013 was not yet be available. The final rule also acknowledged, however, that if data from 2013 became ava ilable before the EPA finalized the area designations, the EPA’s designation decision w ould be based on air quality data from 2011-2013, which are the most recent three cons ecutive years of data (78 FR 3259-51),

The WSV TSD was available to the public for re view in its draft form, and was part of the rulemaking docket for the proposed area designations for the 2012 PM 2.5 Annual NAAQS. The TSD was finalized after consid eration of comments received during the public process provided for the area de signation. The purpose of proposing a draftResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 59 of 68 document as opposed to a final document was to provide an open and transparent process that allowed for meaningful input from both the state and the public at large.

Comment: The commenter states that pages 7, 29, and 31 of the Idaho TSD state include the design values based on 2010

‐ 2012 data, and that the figures will be updated in the
final TSD with 2011

‐ 2013 data. The commenter believes that this will deprive the state and public from being able to adequately comment without a final document.

The commenter states that the technical an alysis gives the West Silver Valley a 12.8

μ g/m 3 design value after excluding only 4 days of exemptions due to exceptional events, and that while additional exceptional event days may exist, exclusion of those days could not lower the design value enough to amount to meet the standard. The commenter states that the EPA has left out 31 da ys that were requested by th e IDEQ and that this could bring the design value down to 12.0 μ g/m 3

.

The commenter further states that the techni cal analysis includes data from surrounding

non -regulatory monitors and areas outside of the Area of Concern, while only one other monitor is listed as being in the Area of C oncern. The commenter states that charts in the TSD are complicated and difficult to read due to font-size and colo r choice. Finally, the commenter states that the analysis omits reference to any established or estimated PM 2.5 concentrations on either a mean or seasona l basis, or to short-term peak background levels PM 2.5 , and points to a 2006 study in Brit ish Columbia, Canada, which the commenter is noteworthy for asse ssing true PM concentrations.

EPA Response: The figures referred to on page s 7, 29, and 31 were generated using a mapping tool that used the 2010-2012 design value as opposed to the 2011-2013 DV data. However, this did not affect the cont ent and purpose of the figures in the TSD as they were used to for the purpose of de picting the area of analysis, population, and vehicle miles traveled respectively and did not reference or use the design value in the figures. The data underlying these figures did not change in the final TSD and several disclaimers were for maps generated usi ng the tool that in corporated the 2010-2012 design value. As noted above, because the incl usion of these figures in the TSD was for informational purposes unrelated to the desi gn value, the ability for the public to comment on the figures was unaffected by the mapping tool’s reference the 2010-2012 design value.

The design value has been correctly calculate d and Table 2a on page 10 of the Idaho TSD provides this information. The IDEQ submitted to the EPA four exceptional event days at the Pinehurst, Idaho monitor for concurrence. The EPA has concurred on all four of these submitted days and the resulting final 2011-2013 design value for the Pinehurst, ID monitor is 12.8 μ g/m 3 . The IDEQ has indicated that th ere are additional days that may potentially qualify as exceptional events days. However, both the EPA and IDEQ have independently confirmed that even if these additional potential exceptional events days were approved and their values were rem oved for purposes of calculating the design value, the monitor’s design value fo r 2011-2013 would still be above the 12.0 μ g/m 3 standard. Information supporting this conclusi on may be found in the docket. The IDEQResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 60 of 68 has indicated that it may submit additi onal exceptional event days for the EPA concurrence in the future.

The use of multiple monitors within the ar ea of analysis, regulatory and non-regulatory, allows for a more detailed understanding of potential contributors to the violation registered at the Pinehurst monitor fo r 2011-2013. Detailed graphs and emissions inventories are important for understanding emi ssions sources in the nonattainment area. Unfortunately, this can cause difficulty with the color keys and overa ll complexity even though we attempt to make the documentation as readable as possible. In the document background emissions are discussed and cons idered through the urban increment, and seasonal and monthly emissions trends are essential to understand when emissions are affecting the monitor. The 2006 British Columbia cited by this commenter does not provide additional relevant information justif ying a departure from the EPA’s method of analysis for this annual PM 2.5 standard.

Comment: The commenter notes that the EPA’s tec hnical analysis for Illinois is just 8 pages, and does not agree with the I llinois Environmental Protection Agency’s recommendation. The commenter states that th e EPA has used its discretion in the area designation process, and that the West S ilver Valley has been unfairly treated.

The commenter states that the EPA has iden tified that Residential Wood Stoves are the reason for non-attainment in the West Silver Valley. The commenter inquires about the contribution from fireplaces and identifies that fireplaces are not being considered in the upcoming regulations on strengthening the standards on “residential wood heaters”.

The commenter states that most homes th e WSV use fireplaces with inserts, and insinuates that the attainment plan is to replace wood heaters with new devices through a loan & tax credits. The commenter cites that they will be out of the EPA compliance in 5- 7 years, and that many wood heat manufact urers may not be able to meet the requirements. http://www.newsmax.com/Newsfront/epa-woodstoveban/2014/02/23/id/554234/

EPA Response: The EPA strives to maintain a nationally consistent process for designating areas when there is a new or revised air qua lity standard. The area designations require three cons ecutive years of certified air quality monitoring data. The technical analysis for Illinois was for a designation of “uncla ssifiable,” due to pervasive problems affecting monitoring data in the en tire state. These pervasive data problems prevented the EPA from being able to determ ine whether Illinois (and parts of adjacent states) met the NAAQS. Further details can be found elsewhere in this Response to Comments document. The same deficiencies were not present with respect to Idaho.

The WSV TSD identifies resi dential wood combustion as a leading contributor to exceedances of the standard. Residential wood heating encompasses a wide variety of home heating sources incl uding, but not limited to woodstoves and fireplaces.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 61 of 68 A common misconception is that the designatio ns process addresses control strategies. For proposed nonattainment areas, this action only identifies the areas violating the NAAQS, or contributing to such nearby violations. Once the nonattainment area designation becomes finalized, the state and/or lo cal air quality agency will work with the affected community to identify strategies to reduce the emissions in the finalized nonattainment areas. This would be part of the attainment plan development.

The EPA is only considering comments relate d to the proposed area designations for the 2012 Annual PM 2.5 NAAQS. The EPA accepted and is currently reviewing comments on the proposed NSPS for new woodstoves. This comment period is now closed. Information on this action can be found at the docket for Revised NSPS for new Residential Wood Heater s - EPA-HQ-OAR-2009-0734

.

Comment: The commenter states that the EPA’s vi ews regarding the he alth impacts of wood heaters are based on only a handful of old, peer-reviewe d studies. Furthermore, the commenter claims that none of these studies consider short-term human health impacts. The commenter states that the EPA does not use proper science, peer -reviewed studies, or cross-benefit analyses in the designations process.

EPA Response: Significant research forms the basis for the national ambient air quality standards prior to promulgation. The multiyea r process includes planning, integrated science assessment, risk/exposure assessment, and policy assessment. For the 2012 PM 2.5 annual standard revision, the EPA initiate d its review in June 2007. Between 2007 and 2011, the EPA prepared draft and final Integrated Science Assessments, Risk and Exposure Assessments, and Policy Assessmen ts. Multiple drafts of all of these documents were subject to review by the publ ic and were peer reviewed by the EPA’s Clean Air Scientific Advisory Committee (CASAC).

All NAAQS are set to protect public health and the environment for all populations nationwide. The 2012 PM 2.5 standard was adopted in response to a court ruling that remanded the primary annual PM 2.5 standard to the EPA finding the Agency had failed to explain adequately why the standard provide d the requisite protect ion from both shortand long-term exposures to fine particles, including protection for at-risk populations such as children. The resulting 2012 PM 2.5 annual NAAQS provides increased protection for children, older adults, persons with pre-ex isting heart and lung disease, and other atrisk populations against an array of PM 2.5 related adverse health effects that include premature mortality, increased hospital admissi ons and emergency department visits, and development of chronic respiratory disease.

All of the information generated from this pr ocess for the particulate matter standards is publicly available at http://www.epa.gov/ttn /naaqs/standards/pm/s_pm_index.html

.

Comment: The Idaho Department of Lands (IDL) concurs with many statements made by the EPA in the proposal, including with respect to topographical influences on PM 2.5 concentrations in and around the Pinehurst ar ea. However, IDL believes any increase inResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 62 of 68 the non-attainment boundary from the existing PM 10 boundary should be supported by technical data from multiple monitors exceeding the NAAQS.

The commenter prefers a boundary for the 2012 annual PM 2.5 nonattainment area that is coterminous with the existing PM 10 boundary, and that thus would include a smaller portion of Shoshone County. The commenter ques tions the appropriateness of the proposed WSV boundary, specifically to the North of Interstate 90, and believes that the proposed boundary lacked sufficient supporting technical information:

“Pinehurst is in the center of a convergence zone of multiple large mountain drainages. The typical diurnal flow of air referenced in the EPA and DEQ studies do exist. One issue that Pinehurst has is a small pinch point on the North si de of town where Interstate 90 passes over Pine Creek. This point hence the city of Pinehurst

, commonly becomes a stagnant air mass because of the larger influential drainage of the South Fork of the Coeur d ' Alene which is the Interstate 90 corridor to the East. This stagnancy in combination with local valley inversi ons creates a bottle neck for air flow

.

“The times of high accumulation of particulat es fall within the months of December, January and February

. These are the months which cause the area to exceed the annual
PM 2

. 5 standards

. Focused community outreach during these periods of air stagnation would help to improve community educati on, support and reduce air quality degradation. There is insufficient technical data which supports the influence of PM 2.5 contributors outside of the Pine Creek drainage

.

“The IDL believes it is reas onable to delay the implemen tation of the proposed boundary and increase monitoring for two years

. This data would be able to provide the technical reference on making a more reliable d ecision on boundary placement. The standard changed in 2012, not the topography.”

This commenter included data with thei r submission, including Wind Ninja modeling runs for diurnal flow, and wind roses for Pinehurst. The commenter concluded with a suggestion for:

“...the addition of three temporary smoke partic ulate monitors, one in the South Fork of the Coeur d'Alene River drainage in Smelte rville, one in Kingston to the West of Pinehurst and one at the conf luence of the West/ East Fork of Pine Creek, South of Pinehurst. Data from these three additional loca tions would be able to clearly define what the main influences are

, where they come from and what the focus should be for increasing the health standards for Pinehurst Idaho.”

EPA Response: The EPA believes that the proposed nonattain ment area boundary is appropriate based on a weight of evidence analysis that included multiple sophist icated modeling tools. The Wind Ninja modeling results submitted with this comment complement the suite of modeling results in this proposal , but do not contradict those re sults. It is important to point out that the area is in violation of an annual standar d, so analyses are needed to address potential sources impacting the m onitor throughout the full year rather thanResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 63 of 68 focusing only on sources during the most impactful months for PM 2.5 . Regardless of the
PM 10 boundary, modeling results leading to th e proposed (now finalized) nonattainment boundary showed that prescribed fires and sl ash fires were potential contributers to PM 2.5 at the violating monitor during the fall and sp ring seasons. These fires were within the current proposed nonattainment boundaries but beyond the more limited boundaries suggested in this comment.

As identified in the WSV TSD, the area has be en analyzed using a five factor analysis. This includes review of air quality data from the Pinehurst monitor as well as data from monitors in surrounding areas. The decision was also supported by emissions inventory information along with modeling across a mu lti-county domain in Northern Idaho. The weight of evidence from the various analyses identified that the majority of emissions affecting the area were generated within close proximity of the monitor during the wintertime. It also identified that during the shoulder seasons, fall and spring, there are emissions from prescribed and slash burning affecting the monitor. There is sufficient weight of evidence based on current monitoring data to support the nonattainment area at issue here, and to ensure that all emissions contributing to the monitor are within the nonattainment area.

3.2.7. Multi-Region Areas

3.2.7.1. Louisville, KY-IN

Comment: The Kentucky Energy and Environment Cabinet (KEEC) comments that the EPA is inconsistent in applying and evaluating PM 2.5 air quality in th e Louisville, KY-IN Area. KEEC states that the EPA intends to use 2011-2013 data from a monitoring site in Indiana with a violating desi gn value as the basis for a nonattainment designation for the 2012 annual PM 2.5 NAAQS, but has not acted on a pe nding redesignation request for the 1997 annual PM 2.5 NAAQS due to data quality issues with air quality monitors in Jefferson County, Kentucky. KEEC believes that if the EPA is willing to use the ambient air monitoring data from the Clark County, Indiana, monitor for the PM 2.5 nonattainment designation for the 2012 standard, then the EPA should also use the data to finalize the attainment designation for the 1997 standar d, particularly sin ce the Clark County, Indiana, monitor has been the design value monitor for the Louisville KY-IN Area since
2007.

EPA Response: The EPA must consider the monitoring data from all monitors in an area in making a designation decision. While it only takes one monitor in an area to indicate that an area is violating a st andard, it takes all of the monitors in an area to provide assurance that an area is in compliance with that standard. The only complete, qualityassured data from the Louisville, KY-IN Area is from the Clark County, Indiana, monitor which shows a violation of the standard based on 2011-2013 data. Because data are not available for the monitors in Jefferson Count y, Kentucky, it is not apparent to the EPA that the Clark County, Indiana, monitor is th e design value monitor for the Area or what the monitors in Jefferson County, Kentucky, would indicate if these monitors had complete, quality-assured data. The EPA notes that the highest reading monitor in the Area when the EPA finalized the Louisv ille, KY-IN Area designation for the 1997 PM 2.5Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 64 of 68 NAAQS in 2005 was in Jefferson County, Kentuc ky. For all of these reasons, the EPA is designating the Area as nonattainment. However, as the EPA has previously indicated, areas may opt to early certify monitoring data for the EPA’s consideration. In its response letter to the EPA, Indiana stated that the Clark County, Indiana, m onitor is expected to show attainment at that monitor based on 2012-2014 data and that Indiana intends to early certify this data for the EPA’s considera tion. The EPA agrees w ith Indiana. that in the event that the Clark County, Indiana, mon itor has complete, quality-assured data that shows attainment for 2012-2014 at that monitor, it is appropriate for the EPA to designate the Louisville, KY-IN Area as unclassifiable b ecause of the incomplete data in Jefferson County, Kentucky, for 2011, 2012, and 2013. Additionally, it is not anticipated that the monitors in Jefferson County, Kentucky will have complete data for the 2012-2014 time period.

While the EPA’s evaluation of the redesigna tion request for the Louisville KY-IN Area for the 1997 PM 2.5 standard is outside of the scope of the designation process for the 2012
PM 2.5 standards, the EPA notes that complete, quality-assured data for the entire area (i.e., monitors in Indiana and Kentucky) are required to support the redesignation.

Comment: The Kentucky Energy and Environmen t Cabinet (KEEC) notes that the preliminary Technical Support Document for the Louisville, KY-IN Area that the EPA developed and included in its 120-day letter to Kentucky Governor Steven Beshear on August 19, 2014, relied upon emissions data from 2011 and 2012. KEEC notes that additional reductions in PM 2.5 , SO 2 , and NOx will occur in the Louisville KY-IN Area as a result of two emission reduction projects at the Louisville Gas & Electric’s (LG&E) Mill Creek and Cane Run fac ilities that are scheduled fo r completion by the end of 2016. KEEC asks that the EPA designate the Louisville KY-IN Area as unclassifiable/attainment ba sed on the anticipated emissions reductions from these projects and on Indiana’s expected early certificati on of 2014 data.

EPA Response: The EPA appreciates the information regarding the upcoming emissions reductions in PM 2.5 , SO 2 , and NOx at the LG&E’s Mill Creek and Cane Run facilities and is aware of Indiana’s belief that the Clark County, Indiana, monitor will show attainment of the PM 2.5 NAAQS from 2012-2014 at that monitor once 2014 data is certified. For designations, the EPA must base its determination on the air quality data and emissions for the area at the time of th e final designations. As discussed above, the EPA will consider the 2012-2014 data from th is monitor if Indiana early certifies complete, quality-assured data for 2014. The Agency agrees with Indiana that in the event that the Clark County, Indiana, monito r has complete, quality-assured data showing attainment for 2012-2014 at that monitor, it is appropriate for the EPA to designate the Louisville, KY-IN Area as unclassifiable becau se of the incomplete data in Jefferson County, Kentucky for the time period of designations.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 65 of 68 3.2.7.2. Cincinnati-Hamilton, OH-KY

Comment: Ohio EPA (OEPA) commented that the intended boundary for the Cincinnati-Hamilton area should not include the intended partial Warren County. OEPA notes that the EPA’s analysis included demonstrating the percent of total pollutants that Warren county contributes compared to ot her counties in the in tended nonattainment area, including VMT, but due to the fact th at the wind direction is predominantly from the south/southwest, while Warren County is ea st/northeast of the vi olating monitors, the area is not contributing to the violation, or is a “weak cont ributor” and therefore should be designated attainment, rath er than nonattainment based on contribution to the violating
monitors.

EPA Response: In fact, the wind roses shown in Figure 8 of the TSD indicate winds blowing from the northeast direction duri ng a moderate fraction of the 2010-2012 3-year period. Additionally, the EPA’s KDE plots included in the TSD (Figure 9) show a high frequency (greater than 50% of the maximum frequency) of trajecto ries passing over grid cells that include the portions of Warren County that were included as the intended boundary. The EPA also notes that for the 2012 annual NAAQS, the monitor data for the entire calendar year (including on days that are below the level of the NAAQS) are part of the mathematical calculation of whethe r a monitor is nonattainment or not. Thus, contribution is still relevant even during a si ngle season, during days that wind directions are coming from the east/northeast, or during periods that do not have high ambient levels. Accordingly, this was one of the f actors used when including Warren County in
the nonattainment area.

The EPA also notes that during the multifactor analysis the EPA also considered Warren County’s contribution to direct PM from m obile sources moving into Hamilton County (the area with the violating monitors), and furthermore assessed contribution from the population and urban area of Warren County that is part of the c ontinuous Cincinnatimetro area. The mobile sources in particular move into the area where the violations are being monitored, leading to direct contribu tion regardless of wind direction. While the commenter notes that only 5.2% of the ar ea’s commuters are fr om Warren County, the number of VMT for 2011 in Warren County is ov er 2 billion miles, and it had the third highest VMT for the intended nonattainment area , as noted in the TSD sent to the state and posted as part of the FR notice.

The commenter also notes that the area is a “w eak contributor” as far as precursors due to wind direction and the lack of major point s ources in the county; however, the statute is clear in providing for inclusi on in nonattainment areas of areas that “contribute” to the violations. The EPA interprets the term “contri butes” to mean contributes sufficiently to justify inclusion in the nonattainment area, and the EPA’s multifactor test with the various analytical tools is intended to assu re an objective evaluation of the appropriate facts on a case by case basis in each area. Th e EPA has considered multiple factors of analysis, and has applied the same analysis to all counties considered in the area of analysis as outline in the TSD. The EPA’s decision is not contingent on only one part of the analysis, but the analysis as a whole espe cially given that PM is a complex pollutantResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 66 of 68 with contribution from multiple source categor ies as well as multiple pollutants. Hence, the EPA’s use of the weight of evidence approach evaluating the facts and circumstances in each area on a case by case basis, and was done consistently with decision principles to assure comparable treatment in all the designations.

Comment: The Kentucky Energy and Environment Cabinet (KEEC) provided comments regarding the Kentucky portion of the intended Cincinnati -Hamilton nonattainment area, the partial counties of Boone, Kenton, and Ca mpbell. KEEC comments that they believe the monitored violations are due to local sources only, a nd that monitors measuring attainment both upwind and downwind of th e violating monitor’s shows that the violations are from local sour ces only. The comments point to local rail yards, rail lines, and highways as the sources that are causing the violation given their location to the violating monitors. The comments also cite the EPA’s TSD enclosed with the 120-day letters, noting that the Kentucky counties each account for less than 10% of the emissions for each pollutant or precursor within the area of analysis.

EPA Response: The commenter has not provided em issions associated with these sources allegedly causing the violations, nor has the commenter prov ided any additional evidence that emissions from these sources would be the only contributors of PM monitored at the violating monitors. Very localized s ources may contribute to the violation, along with other sources in the nonatt ainment area. As a general matter, single sources cause concentrations that are only a fraction of the standard, even in their immediate vicinity, and violati ons instead reflect the contri butions of numerous sources throughout an urban area (in addition to si gnificant “background concentrations” from more distant sources). To determine the cont ribution of nearby areas, the EPA provided a multiple factor analysis that looked at the va rious sources of PM in the area, their total emissions, as well as wind direction impacti ng the monitors, and the source of the air mass that cover the continuous nonattainment ar ea through back trajectories (noted as KDEs in the TSD). The three counties (Boone , Kenton, and Campbell) in Kentucky were found to be commonly upwind of the viola ting monitor based on the wind roses and KDEs (see Figures 8 and 9 of the TSD), and to have emissions that the EPA considers contributing to the violation due to both magn itude – as measured in tons per year – as well as composition, with the VMT and populati on in the Kentucky areas contributing to higher upwind emissions. The EPA’s multifactor te st with the various analytical tools is intended to assure an objective evaluation of the appropriate facts on a case by case basis in each area, and the EPA has determined through the weight-of- evidence presented in the TSD that the areas in Kentucky contribu te to the violations in Hamilton County. Moreover, the fact that there are monitors s howing attainment does not prove that there is no contribution from the area, since the nature of PM 2.5 is that a group of sources that may not be causing a violation in one location may in comb ination with other nearby sources be contributing to vi olations elsewhere nearby.

The commenter also notes that emissions from sources in each of the Kentucky areas are 10% or less. The statute does not require the EPA to establish or use a bright line test or threshold (in this case an emissions percentage) to define what constitutes contribution. Indeed, the EPA has said that to do so would potentially resu lt in arbitrary and capricious decisions in areas where such a test would make no sense by including or excluding areasResponses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 67 of 68 without regard to other more relevant inform ation. Hence, the EPA’s use of the weight of evidence approach evaluating the facts and ci rcumstances in each area on a case by case basis, but done consistently with decision principles to assure comparable treatment in all the designations. In this case the emissions from these counties’ sources, plus the meteorology, and the amount of VMT and population were all noted as part of the analysis the EPA conducted in the TSDs that resulted in the determination that these counties contribute to the vi olations in Hamilton County a nd should be included in the
nonattainment area.

3.2.7.3. St. Louis, MO-IL

Comment: The Missouri Department of Natural Resources (MO DNR) reiterates their recommendation that the EPA designate all por tions of Missouri, in cluding those areas in the St. Louis area, as unclassifiable/attainmen t. MO DNR is concerned that if the EPA designates the City of St. Louis and St. L ouis, St. Charles, Franklin, and Jefferson Counties as “unclassifiable” because of uncertainty with the Illinois monitoring data as indicated in the August 19, 2014 letter to Missouri Governor Nixon, then the unclassifiable designa tion may leave the St. Louis ar ea open to a potential future nonattainment area designation when Illinois resolves its PM 2.5 monitoring issues. MO DNR further states that an unclassifiable/atta inment designation is appropriate regardless of the uncertainty of Illinois data because all monitors in Missour i attain the 2012 annual
PM 2.5 NAAQS and are trending downward.

EPA Response: The EPA must consider the monitoring data from all monitors in an area to inform the appropriate designation decision. While it only takes one monitor in an area to indicate that an area is viol ating a standard, it takes all of the monitors in an area to provide assurance that an area is in compliance with that standard. In the case of St. Louis MO-IL, the monitoring data on th e IL portion of the area is invalid, thus the EPA can’t verify if the area would be atta ining. The IL monitors have historically been the design value monitors for the area so relying on attain ing monitors in Missouri is not appropriate as these Missouri monitors have not historica lly had the highest design values in the area. The EPA is using “unclassifiable” for those areas where the EPA was not able to determine based on available information whet her the area is meeting or not meeting the NAAQS or where the EPA was not able to dete rmine that the area contributes to a nearby violation. In this case the EPA cannot de termine if the area meets the NAAQS or determine if the MO area contributes to a nearby violation, thus the EPA is designating all portions of St. Louis Missouri as unclassifiable.

Comment: MO DNR notes that it is inappropriate to include areas in Missouri in an ILMO unclassifiable area based on the TSD for the 1997 annual PM 2.5 NAAQS because at the time that TSD was developed, monitors in Missouri were viol ating the 1997 standard of 15 μg/m 3 and the TSD analysis was based on assessing contribution to a violating Missouri monitor.Responses to Significant Comments 2012 Annual PM 2.5 NAAQS December 17, 2014

Page 68 of 68 EPA Response: The EPA is including areas in Miss ouri because of the uncertainty in both monitored values and potential contribu tions to possible violations of the NAAQS. Because the area has a history of nonattainment the EPA did review past analysis to help inform the unclassifiable boundary determin ation. The EPA does not believe it is inappropriate to consider past analyses to help inform this decision. The EPA also believes that the current distribution of em issions and wind patterns are similar to the historic distribution of emi ssions and wind patterns, and other factors (recognizing the limitations in the available air quality data) suggest a similar area to be contributing to potential violations in Illinois as the EPA found in promulgating designations for the 1997 NAAQS. We agree with Missouri that fu ture attainment/nonattainment boundaries may be different than those found in th e TSD for the 1997 NAAQS, and inclusion as unclassifiable in this designation does not neces sarily indicate this area would contribute to a future violation should one be found to exist.