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III PM2.5 Hotspot Analysis

(extracted from North Carolina's Air Quality Guidelines for Environmental Documents, August 2007)

A PM2.5 Hotspot analysis is required for projects in Catawba, Davidson and Guilford Counties (that meets the PM2.5 hotspot analysis criteria).

The PM2.5 and PM10 Hot-Spot Analysis in Project-Level Transportation Conformity Determinations for the New PM2.5 and Existing PM10 National Ambient Air Quality Standards; Final Rule (March 10, 2006) can be found on the EPA website at the following address: http://www.epa.gov/fedrgstr/EPA-AIR/2006/March/Day-10/a2178.htm

The Transportation Conformity Guidance for Qualitative Hot-spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas (March 2006) can be found on the FHWA website at the following address: http://www.fhwa.dot.gov/environment/air_quality/conformity/policy_and_guidance/tcgfinal.cfm

The PM Hotspot Final Rule and the Transportation Conformity Guidance for Qualitative Hotspot Analyses (website addresses provided above) are the key information documents that will aid in determining if a PM2.5 hotspot analysis will be required in the environmental documents for projects in the PM2.5 nonattainment areas.

A summary of the PM2.5 and PM10 Hot-Spot Analysis in Project-Level Transportation Conformity Determinations for the New PM2.5 and Existing PM10 National Ambient Air Quality Standards; Final Rule (March 10, 2006) is provided in Attachment 1.

A checklist to determine whether or not a project is of air quality concern for PM 2.5 hot spot requirements is provided in Attachment 2.

A checklist that highlights major process steps for projects that require a PM 2.5 qualitative hot spot analysis is provided in Attachment 3.


ATTACHMENT 1

Summary of the PM2.5 and PM10 Hot-Spot Analysis in Project-Level Transportation Conformity Determinations for the New PM2.5 and Existing PM10 National Ambient Air Quality Standards; Final Rule (March 10, 2006)

  1. Hot-Spot analyses are only required for projects of "air quality concern."

  2. Projects of "air quality concern" are outlined in 40 CFR Sections 92.123(b)(1)(i)-(v). These Sections are listed below with their associated preamble discussion.

    Section 93.123(b)(1)(i): New or expanded highway projects that have a significant number of or a significant increase in diesel vehicles;
    Section 93.123(b)(1)(ii): Projects affecting intersections that are at Level-of- Service D, E, or F with a significant number of diesel vehicles, or those that will change to Level-of-Service D, E, or F because of increased traffic volumes from a significant number of diesel vehicles related to the project;

    Examples of Concern:
    • A project on a new highway or expressway that serves a significant volume of diesel truck traffic, such as facilities with greater than 125,000 annual average daily traffic (AADT) and 8% or more of such AADT is diesel truck traffic;
    • New exit ramps and other highway facility improvements to connect a highway or expressway to a major freight, bus, or intermodal terminal;
    • Expansion of an existing highway or other facility that affects a congested intersection (operated at Level-of-Service D, E, or F) that has a significant increase in the number of diesel trucks;
    • Similar highway projects that involve a significant increase in the number of diesel transit busses and diesel trucks.

    Examples not of Concern:
    • Projects that do not meet the criteria under § 93.123(b)(1), such as any new or expanded highway project that primarily services gasoline vehicle traffic (i.e., does not involve a significant number or increase in the number of diesel vehicles), including such projects involving congested intersections operating at Level-of-Service D, E, or F;
    • An intersection channelization project or interchange configuration project that involves turn lanes or slots, lanes or movements, that are physically separated. These kinds of projects improve freeway operations by smoothing traffic flow and vehicle speeds by improving weave and merge operations, which would not be expected to create or worsen PM2.5 or PM10 violations;
    • Intersection channelization projects, traffic circles or roundabouts, intersection signalization projects at individual intersections, and interchange reconfiguration projects that are designed to improve traffic flow and vehicle speeds, and do not involve any increases in idling. Thus, they would be expected to have a neutral or positive influence on PM2.5 or PM10 emissions.

    Section 93.123(b)(1)(iii): New bus and rail terminals, and transfer points, that have a significant number of diesel vehicles congregating at a single location;
    Section 93.123(b)(1)(iv): Expanded bus and rail terminals, and expanded transfer points, which significantly increase the number of diesel vehicles congregating at a single location; and

    Examples of Concern:
    • A major new bus or intermodal terminal that is considered to be a ''regionally significant project'' under 40 CFR 93.101;
    • An existing bus or intermodal terminal that has a large vehicle fleet where the number of diesel busses increases by 50% or more, as measured by bus arrivals.
    Examples not of Concern:
    • A new or expanded bus terminal that is serviced by non-diesel vehicles (e.g., compressed natural gas or hybrid electric vehicles);

    • A 50% increase in daily arrivals at a small terminal (e.g., a facility with 10 buses in the peak hour).

    Section 93.123(b)(1)(v): Projects in or affecting locations, areas, or categories of sites which are identified in the PM10 or PM2.5 applicable implementation plan or implementation plan submission, as appropriate, as sites of violation or possible violation.

  3. The final rule requires a qualitative PM2.5 hot-spot analysis to be completed for project-level conformity determinations for projects of "air quality concern" completed in PM2.5 nonattainment areas on or after April 5, 2006, when PM2.5 conformity requirements apply. Quantitative analyses are not required for these projects at this time since EPA is not requiring quantitative PM2.5 hot-spot analyses under 40 CFR 93.123(b)(4) since quantitative hot-spot modeling techniques and associated EPA modeling guidance still do not exist. Qualitative PM2.5 hot-spot analyses should be completed according to joint EPA and DOT guidance.

  4. Quantitative analyses will be required when modeling techniques and guidance are released by EPA through Federal Register notice.

  5. Categorical hot-spot findings are an option for projects of "air quality concern."

    • This final rule provides for FHWA and FTA to make categorical hot-spot findings as appropriate for PM2.5 and PM10 hot-spot analyses for projects listed in 40 CFR 93.123(b)(1) of today's final rule.

    • The modeled scenarios used by DOT to make categorical hot-spot findings would be derived through consultation and participation by EPA.

    • A project-level conformity determination relying on the categorical finding and meeting all other requirements is still required.

    • Modeling used to support a categorical hot-spot finding must be based on appropriate motor vehicle emissions factor models, dispersion models, and EPA's future quantitative hot-spot modeling guidance. As a result, categorical hot-spot findings will not be made prior to EPA's announcement in the Federal Register that quantitative PM2.5 and PM10 hot-spot analyses are required (40 CFR 93.123(b)(4)).

    • Categorical hot-spot findings must be supported by credible modeling demonstrations showing that project categories will not cause or contribute to new or worsened violations of the air quality standards. Such modeling would need to be derived in consultation with EPA, and consistent with EPA's future PM2.5 and PM10 quantitative hot-spot modeling guidance.

    • Description of process to make a categorical hot-spot finding is outlined in VII. C. 1 of the final rule. The general process is as follows:
      1. FHWA and/or FTA, as applicable, will develop modeling, analyses, and documentation to support the categorical hot-spot finding. This would be done with early and comprehensive consultation and participation with EPA.
      2. FHWA and/or FTA will provide EPA an opportunity to review and comment on the complete categorical hot-spot finding documentation. Any comments would need to be resolved in a manner acceptable to EPA prior to issuance of the categorical hot-spot finding. Consultation with EPA on issue resolution would be documented.
      3. FHWA and/or FTA would make the final categorical hot-spot finding in a memorandum or letter, which would be posted on EPA's and DOT's respective conformity Web sites.
      4. Subsequently transportation projects that meet the criteria set forth in the categorical finding would reference that finding in their project level conformity determination, which would be subject to interagency consultation and the public involvement requirements of the NEPA process and the conformity rule. The existing consultation and public involvement processes would be used to consider the categorical hot-spot finding in the context of a particular project

ATTACHMENT 2

Determination of Project Categorization for PM2.5 Hot-Spot Requirements

Project Name: (fill in information)
Project Number: (fill in project TIP number))
Location (non-attainment area-Guilford, Davidson, Catawba): (fill in information)
Document Type (CE, EA, EIS): (fill in information)
Project Status (PE, ROW, Construction): (fill in information)
FHWA Contact: (fill in information)
NCDOT Contact: (fill in information)

Project Description: (fill in information)

Since (fill in project TIP number) was not found to be a project of air quality concern under 40 CFR 91.123(b)(1), a qualitative PM 2.5 hot-spot analysis is not required. The following statement will be added to the environmental document for the proposed project:

A qualitative PM 2.5 hot-spot analysis is not required for this project since it is not an air quality concern. The Clean Air Act and 40 CFR 93.116 requirements were met without a hot-spot analysis, since this project has been found not to be of air quality concern under 40 CFR 93.123(b)(1). This project meets the statutory transportation conformity requirements without a hotspot analysis.


ATTACHMENT 3

PM 2.5 HOT SPOT ANALYSIS DOCUMENTATION

  1. NCDOT TIP Number and Project Name: ___________________________________

  2. Project Description: _______________________________________________________

  3. PM2.5 non-attainment or maintenance area (county name): ______________________

STEP 1: AIR QUALITY CONCERN STATUS

  1. Project Status (NEPA type) ____________________________________________________

  2. Project Sponsor (State, Local, City, Other) ____________________________________________

  3. Air Quality Concern

    Project of Air Quality Concern. Select one from the list below

    • □ New or expanded highway projects with a significant number of, or increase in, diesel vehicles (125,000 AADT and 10,000 (8%) diesel truck traffic)

    • □ Project affecting intersections with a current or projected LOS D, E, or F and a significant number of diesel vehicles

    • □ New or expanded bus and rail terminals and transfer points that have significant number of diesel vehicles congregating at a single location

    • □ Projects identified in the PM10 and PM2.5 applicable implementation plan as sites of violation or possible violation

STEP 2: ANALYSIS AND DOCUMENTATION

  1. Type of Analysis (review the Transportation Conformity Guidance for Qualitative Hotspot Analysis in PM2.5 and PM10 Nonattainment and Maintenance Areas dated March 2006 for more information)

    Qualitative Select one or both

    • □ Comparison to another location with similar characteristics
      _____________________________________________

    • □ Findings from an air quality study _____________________________________________ (attach summary)

    Documentation To Be Included for the PM2.5 Hot-spot analysis

    • □ Description of project (design and scope)
    • □ Description of existing conditions
    • □ Current emissions and background
    • □ Existing Conditions/Contributing Factors
      • Air Quality
      • Transportation and traffic conditions
      • Built and natural environment
      • Meteorology, climate and seasonal data
      • Transportation Control Measures
    • □ Consider full time frame of area's LRTP
    • □ Description of changes resulting from project
    • □ Description of analysis years that is examined (peak emissions)
    • □ Professional judgment of impact
    • □ Discussion of any mitigation measures
    • □ How does the project meet 40CFR 93.116 & 93.123 for PM2.5

Meetings, Notices, Dates

  1. Transportation Conformity (TC) Interagency Consultation (IC) meeting(s) __________ (attach minutes)
    (EPA, NCDENR-DAQ, FHWA, FTA)

  2. TC IC review and comment on Qualitative PM 2.5 Hotspot Analysis

FHWA ________________ (date)

NCDENR-DAQ ________________ (date)

FTA ________________ (date)

EPA ________________ (Date)

(attach documentation showing review comments and resolution of those comments)


  1. Public Involvement

    1. Public notice (should be consistent with NEPA project)__________________________________ (attach)

    2. Public review & comment period (should be consistent with NEPA project) ____________________ (dates)

    3. Public concerns addressed ___________________________________________

STEP 4: SIGNATURES


______________________________________________ ______________ (Date)
NCDOT Project Manager


______________________________________________ ______________ (Date)
FHWA Representative
Updated: 07/06/2011
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