A number of emerging legislative and policy issues will impact transportation conformity in the future. State and local transportation and air agencies should monitor these developments in order to anticipate and understand their impacts on transportation conformity.
On April 30, 2004, EPA finalized the Phase 1rule implementing the 8-hour ozone National Ambient Air Quality Standards (NAAQS) and made final designations and classifications (40 CFR Parts 81, 50, and 51), effective June 15, 2004. Transportation conformity under the 8-hour ozone standard applied on June 15, 2005. On November 29, 2005, EPA promulgated the second phase of the implementation rule (70 FR 71612). Phase 2 of the implementation rule explains how attainment demonstrations and modeling, reasonable further progress, reasonably available control measures, reasonably available control technology, new source review, and reformulated gasoline must be addressed in 8-hour ozone nonattainment areas. A future update of this Reference Guide will reflect information in the Phase 2 implementation rule.
In the April 30, 2004 rulemaking, EPA deferred the designations for Early Action Compact areas. Early Action Compacts are agreements signed by representatives of local communities, State and Tribal air quality officials, and EPA Regional Administrators that provide for control of emissions under the 8-hour standard earlier than the Clean Air Act would otherwise require. Early Action Compact areas that meet defined milestones are eligible for a deferral of the effective date of 8-hour nonattainment designations. For more information on the implementation of the 8-hour standard: www.epa.gov/ttn/naaqs/ozone/o3imp8hr/.
In November 2005 EPA released its draft staff paper on its periodic review of the ground-level ozone standard. The public comment period ends on January 17, 2006. As part of EPA's review process, EPA develops a criteria document, a compilation and evaluation by EPA scientific staff and other expert authors of the latest scientific knowledge useful in assessing the health and welfare effects of the air pollutant under review. The Ozone Criteria Document presents the latest available pertinent information on atmospheric science, air quality exposure, health effects and environmental effects of ozone and other related photochemical oxidants. While this effort is somewhat behind the review of the PM standards, further information will be available on the EPA website as the ozone standard review process proceeds. The recently released draft staff paper can be seen at: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_index.html
On January 5, 2005 EPA announced the final designations for the fine particulate standard (40 CFR Part 81), effective on April 5, 2005. A twelve-month grace period applies nonattainment areas to meet the conformity requirements, so transportation conformity under the PM2.5 standard will apply on April 5, 2006. By this date, metropolitan transportation plans and TIPs in PM2.5 nonattainment areas must be found to conform under the PM2.5 standard, or conformity will lapse. For more information on the implementation of the PM2.5 standard: http://www.epa.gov/ttn/naaqs/pm/pm25_index.html. EPA finalized the precursor rule on May 6, 2005. The transportation conformity requirements for PM2.5 hot-spots are not yet finalized and EPA intends to finalize the requirements by March 2006.
Under the Clean Air Act, EPA must review the National Ambient Air Quality Standards (NAAQS) for six criteria pollutants every five years to ensure the standards are protective of public health and welfare. EPA conducts its review to ensure that the standards reflect the latest research on pollution and its impact on public health. Based on its review of the air quality criteria and national ambient air quality standards (NAAQS) for particulate matter (PM), EPA is proposing to make revisions to the primary and secondary NAAQS for PM to provide requisite protection of public health and welfare, respectively, and to make corresponding revisions in monitoring reference methods and data handling conventions for PM.
With regard to primary standards for fine particles (particles generally less than or equal to 2.5 micrometers (μm) in diameter, PM2.5), EPA proposes to revise the level of the 24-hour PM2.5 standard to 35 micrograms per cubic meter (μg/m3), providing increased protection against health effects associated with short-term exposure (including premature mortality and increased hospital admissions and emergency room visits) and to retain the level of the annual PM2.5 standard at 15 μg/m3, continuing protection against health effects associated with long-term exposure (including premature mortality and development of chronic respiratory disease). The EPA solicits comment on alternative levels of the 24-hour PM2.5 standard (down to 25 μg/m3 and up to 65 :g/m3) and the annual PM2.5 standard (down to 12 μg/m3), and on alternative approaches for selecting the standard levels.
With regard to primary standards for particles generally less than or equal to 10 μm in diameter (PM10), EPA proposes to revise the 24-hour PM10 standard in part by establishing a new indicator for thoracic coarse particles (particles generally between 2.5 and 10 μm in diameter, PM10-2.5), qualified so as to include any ambient mix of PM10-2.5 that is dominated by resuspended dust from high-density traffic on paved roads and PM generated by industrial sources and construction sources, and excludes any ambient mix of PM10-2.5 that is dominated by rural windblown dust and soils and PM generated by agricultural and mining sources. The EPA also proposes that agricultural sources, mining sources, and other similar sources of crustal material shall not be subject to control in meeting the proposed standard. The EPA proposes to set the new PM10-2.5 standard at a level of 70 μg/m3, continuing to provide a generally equivalent level of protection against health effects associated with short-term exposure (including hospital admissions for cardiopulmonary diseases, increased respiratory symptoms and possibly premature mortality). Also, EPA proposes to revoke, upon finalization of a primary 24-hour standard for PM10-2.5, the current 24-hour PM10 standard in all areas of the country except in areas where there is at least one monitor located in an urbanized area (as defined by the U.S. Bureau of the Census) with a minimum population of 100,000 that violates the current 24-hour PM10 standard based on the most recent three years of data. In addition, EPA proposes to revoke the current annual PM10 standard upon promulgation of this rule. The EPA solicits comment on alternative approaches for selecting the level of a 24-hour PM10-2.5 standard, on alternative approaches based on retaining the current 24-hour PM10 standard, and on revoking and not replacing the 24-hour PM10 standard.
For more information, see: www.epa.gov/ttn/naaqs/standards/pm/s_pm_index.html.
To keep pace with new analysis needs, new modeling approaches, and new data, the EPA's Office of Transportation and Air Quality (OTAQ) is currently working on a new modeling system termed the Multi-scale mOtor Vehicles and equipment Emission System (MOVES). This new system will estimate emissions for on-road and nonroad sources, cover a broad range of pollutants, and allow multiple scale analysis, from fine-scale analysis to national inventory estimation. This project was previously known as the New Generation Mobile Source Emissions Model (NGM).
On January 6, 2005, EPA announced the draft release of the first version of the MOVES, MOVES2004, and supporting documents covering model use, design, and technical inputs. This release initiates a six-month comment period to allow model stakeholders to review and provide comment on any aspect of the model or documentation.
MOVES will eventually expand to replace MOBILE6 and NONROAD, the official models for estimating mobile sources emissions; at this time, however, MOVES2004 is being released for review purposes only and does not affect the official status of MOBILE6 or NONROAD. EPA expects to make annual releases of upgraded versions of MOVES, adding pollutants and sources over the next four years and updating underlying data as needed. MOVES2004 provides the basis for these future releases in terms of software design and interface, and by incorporating new methodologies and data for characterizing the on-road vehicle petroleum-based and fossil-based) and emissions of methane and nitrous oxide for all on-road sources, over the entire U.S. at the county level, from 1999 through 2050. The MOVES2004 package also includes an updated version of Argonne National Laboratories' GREET model, with a built-in interface, to allow integrated estimation of “well-to-pump” energy and emission effects. For more information, please see: www.epa.gov/otaq/ngm.htm.
Over the past two years the need to reduce emissions from in-use diesel vehicles has become well understood. This is because even though existing EPA regulations will reduce diesel emissions dramatically over the next twenty years, the durability of diesel engines enables their owners to operate these vehicles for up to 20 years. It is not uncommon for diesel trucks to operate for over 1 million miles during their useful life. The same durability applies to non-road diesel engines. With the development of retrofit technologies, emissions from old diesel engines (both on-road and non-road) can be significantly reduced and are very cost-effective emission reduction strategies. EPA has established a voluntary diesel retrofit program and many states are promoting retrofits as a way to reduce particulates, especially in PM10 and PM2.5 nonattainment areas. Retrofit technologies include diesel oxidation catalysts (DOCs), particulate filters, and lean NOx catalysts. Examples of retrofit applications include school buses, transit buses, refuse trucks, construction equipment, port-related equipment and agricultural equipment. For information on retrofit programs see: www.westcoastdiesel.org, EPA's West Coast Diesel Collaborative, www.epa.gov/otaq/retrofit/ or www.dieselforum.org.
SAFETEA-LU was signed into law on August 10, 2005. USDOT and EPA are currently developing interim guidance to address the conformity provisions in the new transportation bill. Congress gave EPA 2-years (August 10, 2007) from the date of enactment of SAFETEA-LU to promulgate revised transportation conformity regulations to implement the changes in the transportation bill.