SEPA United States Environmental Protection Agency Office of Transportation & Air Quality EPA-420-B-13-056 November 2013 Transportation Conformity Guidance for Quantitative Hot-spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas Guidance Change Bulletin: November 2013 Part of Guidance Change from 2010 Guidance to 2013 Guidance Reason for Change Section 5: Estimating Project- Level PM Emissions Using EMFAC (in California) Revised former EMFAC2007 section to reflect EMFAC2011 EPA approved EMFAC2011 for PM hot-spot analyses (78 FR 14533) and committed to update the 2010 guidance to reflect the new model Section 7.6.1: Placing Receptors. Overview Deleted Exhibit 7-4 and reorganized in accordance with revisions to former Sections 7.6.2 and 7.6.3 (see below) In EPA's 2012 PM NAAQS final rule (78 FR 3264), EPA committed to review the guidance and revise as necessary in accordance with the PM2 5 NAAQS and air quality monitoring regulatory revisions Section 7.6.2: General guidance for receptors for all PM NAAQS Revised examples for finer and wider receptor spacing to only include outer range; for example "finer spacing (e.g., 10-25 meters)" changed to "finer spacing (e.g., 25 meters)" Reflect latest information from guidance implementation to date so that PM hot-spot analyses include appropriate spacing while using state and local resources efficiently Section 7.6.3: Additional Guidance for Receptors for the PM25NAAQS Deleted Reflect 2012 PM NAAQS final rule Section 9.1-9.3: Calculating PM Design Values and Determining Conformity Clarified Exhibit 9-2 and sentences that refer to Section 9.4 to be consistent with revised Section 9.4 (see below) Reflect 2012 PM NAAQS final rule Section 9.4: Determining Appropriate Receptors for Comparison to the Annual PM2 5 NAAQS Revised in its entirety Reflect 2012 PM NAAQS final rule Appendix G: Example of Using EMFAC for a Highway Project Revised to reflect use of EMFAC2011 Reflect latest approved EMFAC model Appendix H: Example of Using EMFAC to Develop Emission Factors for a Transit Project Revised to reflect use of EMFAC2011 Reflect latest approved EMFAC model ------- |