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Transportation Conformity and the New Air Quality Standards - Frequently Asked Questions

  1. Overview and Background
  2. Early Action Compacts
  3. When Must You Do Conformity?
  4. Conformity Under the 8-Hour Ozone Standard
  5. Multi-jurisdictional Areas
  6. Conformity under the PM2.5 Standard
  7. Conformity SIPs
  8. Transportation Planning

A. Overview and Background

Q1: When did the transportation conformity rule amendments to address the new standards come out, and where are they available?

A: The final rule was published in the Federal Register on July 1, 2004. It is available at: http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-01/a14213.htm. This final rule revises the transportation conformity rule to include criteria and procedures for the 8-hour ozone and fine particulate matter (PM2.5) national ambient air quality standards, to address a March 2, 1999 court decision, and to provide some streamlining provisions. This final rule is based on two proposals. The November 4, 2003 proposal regarding the new standards is available at http://www.epa.gov/fedrgstr/EPA-AIR/2003/November/Day-05/a27372.htm, and the June 30, 2003 proposal regarding the court decision is available at http://www.epa.gov/fedrgstr/EPA-AIR/2003/June/Day-30/a15253.htm.

Q2: Was a corrections notice issued for this final rule?

A: Yes, there were two minor errors in the July 1, 2004 final rule's preamble. These corrections were published in the Federal Register on July 20, 2004. These corrections did not affect the substance of the rule. This notice is available at: http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-20/a16449.htm.

Q3: Did the July 1, 2004 rulemaking finalize regulations for all aspects of implementing the new standards?

A: No. Two aspects of conformity for the PM2.5 standard were not finalized. The first was provisions to address how PM2.5 precursors will be addressed in conformity analyses. EPA published final conformity rule amendments that address PM2.5 precursors on May 6, 2005, which are available at: http://www.epa.gov/fedrgstr/EPA-AIR/2005/May/Day-06/a9086.htm. The preamble to the May 6, 2005 final rule contained two minor errors. Corrections were published in the Federal Register on June 1, 2005, and are available at: http://www.epa.gov/fedrgstr/EPA-AIR/2005/June/Day-01/a10853.htm. The second aspect was provisions to address if and how hot-spot analysis requirements should apply for PM2.5. On December 13, 2004, EPA issued a supplemental notice of proposed rulemaking that provides additional options to address localized PM2.5 emissions, as well as PM10 emissions. This supplemental proposal is available at: http://www.epa.gov/fedrgstr/EPA-AIR/2004/December/Day-13/a27171.htm. EPA is currently considering comments that were received on the December 13, 2004 supplemental proposal, as well as comments received on the November 5, 2003 proposal, and plans to issue a final rule to address PM hotspots later this year.

Q4: Does the July 1, 2004 notice include the complete Transportation Conformity Rule?

A: No. The notice only included those sections of the rule that were being changed. A complete version of the regulations is available at 40 CFR Parts 51 and 93. In addition, the complete Rule as amended is available at http://www.fhwa.dot.gov/environment/air_quality/conformity/rule.cfm.

Q5: When will conformity apply in 8-hour ozone nonattainment areas?

A: EPA's 8-hour nonattainment designations were published in the Federal Register on April 30, 2004, effective June 15, 2004. Therefore, in these nonattainment areas, conformity under the 8-hour standard started applying June 15, 2005, with the exception of Early Action Compact areas (see section B. below) and the Las Vegas, NV area (conformity under the 8-hour standard will apply September 13, 2005). For more information on ozone designations see EPA's website at: http://www.epa.gov/ozonedesignations/.

Q6: When will conformity apply in PM2.5 nonattainment areas?

A: EPA's PM2.5 nonattainment designations were published in the Federal Register on January 5, 2005, effective April 5, 2005. Therefore, in these nonattainment areas, conformity under the PM2.5 standard will apply April 5, 2006. For more information on PM2.5 designations, see EPA's website at: http://epa.gov/pmdesignations/.

Q7: Can FHWA/FTA or EPA extend the 1-year grace period from the effective date of final nonattainment designation before conformity applies?

A: No, the 1-year grace period is statutory, so no Administrative flexibility can be offered.

B. Early Action Compacts

Q1: What are Early Action Compacts?

A: In December 2002, a number of areas submitted agreements pledging to meet the 8-hour ozone standard earlier than required. Early voluntary 8-hour ozone air quality plans are developed through a Compact between local, State, and EPA officials. These Early Action Compacts (EACs) were available only to areas attaining the 1-hour ozone standard, but approaching or monitoring exceedances of the 8-hour standard. Areas and States with EACs had to meet a number of criteria, and have to meet certain milestones. In exchange, EPA agreed to officially defer 8-hour ozone nonattainment designations until September 30, 2005. Before September 30, 2005 (the date of the first deferral), EPA intends to promulgate the second deferred effective date until December 31, 2006, provided Compact areas meet required milestones. Before December 31, 2006, EPA intends to promulgate the third deferral until April 15, 2008, provided Compact areas complete all remaining milestones and reports. If areas meet all milestones and attain the 8-hour ozone standard, EPA will at that time officially designate Compact areas attainment. If a Compact area fails a milestone, EPA will end the deferral. Fourteen areas have had their 8-hour nonattainment designation effective date deferred under an EAC. Additional information on EACs is available at http://www.epa.gov/air/eac/.

Q2: If a Compact areas deferral is ended, and its nonattainment designation for the 8-hour standard becomes effective, when will conformity apply?

A: If a Compact area's deferral is ended, conformity for the 8-hour standard will apply one year after the effective date of the designation. For example, if a Compact area misses a milestone and its deferral ends, and its 8-hour nonattainment designation becomes effective on September 30, 2005, conformity under the 8-hour standard would apply on September 30, 2006.

Q3: Does conformity apply to an EAC area currently operating under a 1-hour maintenance plan?

A: Yes. EAC areas with a maintenance plan (Denver-Boulder, CO; Greensboro-Winston Salem-High Point, NC; and Nashville, TN) for the 1-hour standard must continue implementing conformity requirements as long as the 1-hour standard is in place. The 1-hour standard is not being revoked for these areas on June 15, 2005. Instead, for Compact areas, the 1-hour standard will be revoked 1 year after the effective date of the designation of attainment or nonattainment for the 8-hour standard. For example, if a Compact area is designated attainment for the 8-hour standard in April 2008, then the 1-hour standard would be revoked one year after the effective date of this designation, and conformity for the 1-hour standard would no longer apply (i.e., April 2009). If a Compact area's deferral is ended, and its nonattainment designation for the 8-hour standard becomes effective, the 1-hour standard will be revoked one year from the effective date. So, the area would no longer be subject to conformity under the 1-hour standard once it is revoked. However, the area would be subject to conformity under the 8-hour standard at that time.

Q4: If a Compact area is designated nonattainment under the PM2.5 standard, do they have to meet conformity requirements?

A: Yes. If a Compact area is designated nonattainment under the PM2.5 standard, they will have to meet the PM2.5 conformity requirements when the PM2.5 conformity grace period ends on April 5, 2006. However, they would not have to meet the 8-hour conformity requirements as long as their 8-hour deferral was in place. Several Compact areas were designated nonattainment under the PM2.5 standard, including: Greensboro-Winston Salem-High Point, NC (1-hour maintenance); Martinsburg-Hagerstown, MD-WV; Hickory-Morgantown-Lenoir, NC; and Chattanooga, TN-GA.

Q5: Where can I get more information on conformity and EACs?

A. For more information on conformity and EACs, please see Section III.D. of EPA's July 1, 2004 final rule preamble (69 FR 40014), which is available at http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-01/a14213.htm.

C. When Must You Do Conformity?

Q1: When do metropolitan plan and TIP conformity determinations need to be in place for the new standards?

A. Areas that are designated nonattainment for the 8-hour ozone and/or PM2.5 standard must determine conformity of metropolitan transportation plans and TIPs by the expiration of the one-year conformity grace period for a relevant pollutant and standard; June 15, 2005 for the 8-hour ozone standard and April 5, 2006 for the PM2.5 standard. Metropolitan and donut 8-hour ozone and PM2.5 nonattainment areas must complete all of the tasks that are required for a conformity determination (e.g., interagency consultation, regional emissions analyses, public participation, MPO and DOT conformity determinations) during the relevant grace period in order to avoid a conformity lapse upon the expiration of the grace period. For more information, see Section III.A-C of the July 1, 2004 rulemaking (69 FR 40008-40014), which is available at http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-01/a14213.htm.

Q2: When is project-level conformity for the new standards required?

A. Once the conformity grace period expires (June 15, 2005 for the 8-hour ozone standard and April 5, 2006 for the PM2.5 standard), a project-level conformity determination is required whenever a non-exempt project completes the NEPA process, as defined in 40 CFR 93.101. For projects that complete the NEPA process prior to the end of the conformity grace period without a conformity determination for a new standard, a project-level conformity determination would be required for the next project phase that requires FHWA/FTA approval. For more information, see Section III.A-C of the July 1, 2004 rulemaking, which is available at http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-01/a14213.htm.

Q3: If an area can demonstrate 8-hr conformity during the grace period, do they still have to meet the 1-hour conformity requirements?

A: Yes. You have to continue to meet the 1-hour conformity requirements until the 1-hour standard is revoked if a 1-hour conformity determination is required (e.g., new or amended transportation plan or TIP, or a conformity trigger for the 1-hour standard under 40 CFR 93.104(e)). EPA decided in its April 30, 2004 8-hour implementation final rule (69 FR 23969, available at http://www.epa.gov/fedrgstr/EPA-AIR/2004/April/Day-30/a9153.htm) to revoke the 1-hour ozone standard one year after 8-hour nonattainment designations become effective, which coincides with the end of the grace period provided in the Clean Air Act.

Q4: If an area voluntarily determines 8-hour conformity early, would that start the three-year update clock?

A: Yes, if the 8-hour conformity determination is based on a new regional emissions analysis (see below). For example, if FHWA/FTA determines 8-hour conformity of an MPO's transportation plan and TIP, based on a new regional emissions analysis, on April 1, 2005, the 3-year update clock would start on April 1, 2005. Therefore, the next 8-hour conformity determination based on a new regional emissions analysis would be required by April 1, 2008. However, plan/TIP update requirements, as well as the conformity frequency requirements of 40 CFR 93.104(b), (c), and (e) for other pollutants, would still apply. In other words, the 8-hour conformity determination in this case might not satisfy the plan/TIP update frequency requirements of the planning regulations, nor the frequency requirements of 40 CFR 93.104(b), (c), and (e) for other applicable pollutants.

Q5: Can an MPO rely on a previous regional emissions analysis, or portion thereof, conducted for a 1-hour ozone conformity determination to determine conformity for the 8-hour ozone standard?

A: Yes, provided that they meet the requirements in 40 CFR 93.122(g). In particular, the regionally significant projects in the plan/TIP must be consistent with those assumed in the previous regional emissions analysis, and the design concept and scope of each regionally significant project cannot be significantly different from that assumed in the previous regional emissions analysis. In addition, the previous regional emissions analysis must be consistent with the requirements of 40 CFR 93.118 or 93.119, as appropriate. In particular, if the budget test is being performed under 93.118, the 8-hour attainment year must be included as an analysis year, and the previous regional emissions analysis must demonstrate conformity to all currently applicable budgets.

Q6: When does the three-year conformity update clock begin for an area that relies on a previous regional emissions analysis?

A: A new plan/TIP conformity determination based on a completely new regional emissions analysis is required every three years from the date of FHWA/FTA's determination. If a conformity determination relies on any part of a previous regional emissions analysis, the frequency requirements of 40 CFR 93.104(b) or (c) are not satisfied.

Q7: If the previous regional emissions analysis did not analyze the 8-hour attainment year, can the MPO rely on the previous regional emissions analysis for the other analysis years required, and only perform a new analysis for the 8-hour attainment year?

A: No. However, if nothing else has changed for those analysis years and the previous analysis for those years is exactly what would be generated if a new analysis was performed (i.e., the latest planning assumptions and emissions models have not changed), the modeling for those analysis years would not have to be repeated. In other words, if there have been no changes in the area's plan and TIP, and more recent planning assumptions under 40 CFR 93.110 have not become available, and a new emissions model under 93.111 has not become available, and all other applicable requirements have been met, the MPO could include the applicable analyses from the previous conformity determination.

Q8: Does a conformity determination for the 8-hour ozone standard or the PM2.5 standard need to be accompanied by conformity determinations for other applicable pollutants?

A: Not necessarily. As long as the transportation plan/TIP have not been updated or amended, a conformity determination for the 8-hour or PM2.5 standard would not need to address other pollutants for which the area might be nonattainment or maintenance. However, plan/TIP update requirements, as well as the frequency requirements of 40 CFR 93.104(b), (c), and (e) for the other pollutants, would still apply. In other words, the 8-hour or PM2.5 conformity determination in this case would not satisfy the plan/TIP update frequency requirements of the planning regulations (23 CFR 450), nor the frequency requirements of 40 CFR 93.104(b), (c), or (e) for the other applicable pollutants.

Q9: Isn't conformity under the PM2.5 standard on a different timetable?

A: Yes. Conformity under the PM2.5 standard will apply on April 5, 2006. Therefore, areas designated nonattainment for both the 8-hour ozone and PM2.5 standards may wish to carefully examine their timelines for conformity determinations and transportation plan and TIP updates to meet the different deadlines.

Q10: Can an area be in conformity under the 8-hour standard, but not in conformity for the PM2.5 standard?

A: Yes, that is a possibility. If an area is designated nonattainment for both the 8-hour ozone standard and the PM2.5 standard, then they must meet the conformity requirements for both pollutants. For example, an area might be able to meet the requirements for ozone, but not for PM2.5. In that case, the portion of the MPO contained within the PM2.5 nonattainment would enter a conformity lapse. However, if a portion of the MPO is within the 8-hour ozone nonattainment area, but not within the PM2.5 nonattainment area, that portion would not lapse.

D. Conformity Under the 8-Hour Ozone Standard

Q1: How do I do conformity for the 8-hour standard if I have no adequate or approved 1-hour SIP budgets?

A: The general criteria in 40 CFR 93.109(d) applies, since these areas do not have adequate or approved 1-hour budgets. For more information, see Section V. of the July 1, 2004 rulemaking (69 FR 40019-40021), which is available at http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-01/a14213.htm.

Q2: What "scenario" is an area that is designated nonattainment under the 8-hour ozone standard, but (a) no part was designated nonattainment/maintenance under the 1-hour standard or (b) was designated nonattainment or maintenance under the 1-hour standard, but no part is covered by adequate or approved budgets under the 1-hour standard?

A: None of the four scenarios described in the conformity rule applies to the area described in (a) or (b) above. The July 1, 2004 rulemaking identified four "scenarios" (40 CFR 93.109(e)) to describe 1-hour nonattainment/maintenance areas with approved or adequate budgets that are designated 8-hour nonattainment Instead, the general criteria in 40 CFR 93.109(d) applies, since these areas do not have adequate or approved 1-hour budgets.

Q3: For Scenario 3 or 4 areas that choose to meet the interim emissions test(s) for the whole nonattainment area, instead of just the additional area outside of the 1-hour nonattainment/maintenance area, do they still have to demonstrate conformity to the 1-hour budgets?

A: Yes. Even though these areas have the option of conducting the interim emissions test(s) for the entire area, they are still required to meet the 1-hour budgets within the 1-hour ozone nonattainment area (or portion thereof for Scenario 4 areas). For more information, see Section VI. of the July 1, 2004 rulemaking (69 FR 40021-40028), which is available at http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-01/a14213.htm.

Q4: Does an area have to determine whether the interim tests are more appropriate in meeting the Clean Air Act requirements if they have existing 1-hour budgets?

A: No. Adequate or approved 1-hour budgets can be used without making a separate determination to see if the interim emissions tests are more appropriate.

NOTE:On October 20, 2006, the DC Circuit U.S. Court of Appeals vacated 40 CFR 93.109(e)(2)(v). 8-hour ozone areas that do not have adequate or approved 8-hour budgets can no longer utilize this provision to use the interim emissions tests instead of their 1-hour budgets to demonstrate conformity. Please see: (Circuit Court Ruling)

Q5: When are 8-hour SIPs due, and when will motor vehicle emissions budgets become available?

A: Areas have three years to submit attainment SIPs, until 2007. However, areas can make early SIP submissions; areas don't have to wait until 2007 to submit attainment SIPs. In addition, they can also submit an early SIP that may not show attainment, but that shows progress towards attainment and contains budgets. For more information, see Section V.A.1. of the July 1, 2004 rulemaking (69 FR 40019), which is available at http://www.epa.gov/fedrgstr/EPA-AIR/2004/July/Day-01/a14213.htm.

Q6: Does an 18-month clock for a 1-hour ozone SIP budget continue to apply for 8-hour conformity after the 1-hour ozone standard is revoked? Does an EPA adequacy finding or approval of a 1-hour ozone SIP budget after revocation trigger a new 18-month clock for 8-hour conformity?

A: No, for both questions. Section 93.104(e) of the transportation conformity rule only applies for 8-hour conformity when 8-hour ozone SIP budgets are found adequate or approved. More specifically: any 1-hour ozone-related 18-month clocks that have been triggered will go away when the 1-hour standard is revoked, and any 1-hour ozone SIP budgets that are found adequate or approved after revocation will not trigger new 18-month clocks for 8-hour conformity. This answer is appropriate even in the case where an adequate or approved 1-hour SIP budget is being used for 8-hour conformity.

E. Multi-jurisdictional Areas

Q1: How do you implement conformity in multi-jurisdictional or complex areas?

A: EPA's "Companion Guidance for the July 1, 2004, Final Transportation Conformity Rule: Conformity Implementation in Multi-jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality Standards (EPA420-B-04-012, July 2004)" guidance is available at: www.epa.gov/otaq/stateresources/transconf/policy.htm#require. This guidance document describes how conformity determinations apply in areas that contain more than one MPO, a donut area, parts of more than one state, or any combination. In addition, FHWA has completed a study of current transportation conformity practices in these types of "complex" areas. It is available at: www.fhwa.dot.gov/environment/air_quality/conformity/research/complex_areas/.

Q2: Does the conformity guidance for multi-jurisdictional areas apply only to the 8-hour standard, or does it also apply to PM2.5 and other standards?

A: EPA's "Conformity Implementation in Multi-jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality Standards (EPA420-B-04-012, July 2004)" guidance is applicable to all pollutants. Although some portions of this guidance are applicable only to 8-hour nonattainment areas with 1-hour budgets (i.e., Part 4 of the guidance), the rest of the guidance is applicable to all pollutants.

Q3: Who is responsible for conducting the regional emissions analysis for a donut area?

A: In a nonattainment or maintenance area with a donut area, the lead agency for developing the regional emissions analysis that applies to the donut area can be:

Section 93.105(c)(3) of the conformity rule relies on the interagency consultation process (including the MPO and state DOT) to determine how best to consider projects that are planned for donut areas located outside the metropolitan area and within the nonattainment or maintenance area in the conformity process. Section 93.105 also requires that such procedures for demonstrating conformity of donut area projects be included in an area's conformity SIP that is approved by EPA according to §51.390 of the rule. See question 7 in Part 2 of EPA's multi-jurisdictional guidance.

Q4: If a nonattainment area with multiple MPOs, within a single State, does not have sub-area budgets, can each MPO develop their regional emissions analysis separately? Can they determine plan/TIP conformity separately?

A: Each MPO can develop their portion of the regional emissions analysis separately. However, these separate analyses would have to be combined to cover the entire nonattainment area in order to demonstrate conformity. Each MPO would then separately determine conformity of their plan and TIP based on this compiled analysis. After all of the MPOs within the area had submitted their conformity determinations, FHWA/FTA would make their plan/TIP determinations for all of the MPOs at the same time. See questions 3 and 4 in Part 2 of EPA's multi-jurisdictional guidance.

Q5: A nonattainment area in one or more states contains multiple MPOs, and this nonattainment area does not have adequate or approved SIP budgets. Do all the MPOs in the nonattainment area need to determine conformity every time one of the other MPOs wants to update or revise its plan or TIP?

A. Yes. Section 93.124(d) of the conformity rule states that, "Where a nonattainment area includes multiple MPOs, the control strategy SIP may either allocate emissions budgets to each metropolitan planning area, or the MPOs must act together to make a conformity determination."

As explained in Part 2, Q&A #3, of EPA's July 21, 2004, multi-jurisdictional area guidance, to satisfy the Clean Air Act and conformity rule requirements, conformity determinations and regional emissions analyses in multiple-MPO nonattainment areas must address the entire nonattainment area when there are no SIP budget(s). That is, before a SIP is submitted with budgets that are found adequate or approved, conformity determinations must be supported by a regional analysis that considers emissions from the entire area, and DOT must make all plan/TIP conformity determinations from the individual MPOs at the same time. If one MPO is unable to meet the conformity requirements for its plan and TIP, the other MPOs in the area also cannot demonstrate conformity.

In nonattainment areas that include more than one MPO, Part 2, Q&A #4, of EPA's July 2004 guidance describes two ways in which MPOs can develop the regional emissions analysis for the area. The MPOs can:

In either case, all the MPOs must use the same interim emissions test and analysis years for the regional emissions analysis to make the demonstration required by the conformity rule.

Q6. If one of the MPOs in the scenario in Q5. wants to update its plan/TIP to add a new project (a change that would require a new regional emissions analysis), do the other MPOs also need to conduct a new emissions analysis, or can they simply re-submit their portion of the previous regional analysis to demonstrate conformity (assuming separate modeling was conducted for the previous analysis)?

A. The other MPOs may be able to rely upon their previous regional emissions analyses for their respective conformity determinations, provided that each MPO can meet the requirements of §93.122(g). Section 93.122(g) of the conformity rule allows MPOs to rely on a previous emissions analysis for plan and TIP conformity determinations so long as the plan and TIP do not include additions or deletions of regionally significant projects, significant changes in the design concept and scope of existing regionally significant projects, or changes to the time frame of the transportation plan. Further, minor plan and TIP revisions under §93.122(g) must not include revisions that delay or accelerate the completion of regionally significant projects across conformity analysis years and cannot satisfy the three-year conformity update requirement. Section 93.122(g)(iv) also requires that previous emissions analysis must be consistent with §93.118 and/or §93.119 requirements, as applicable.

§93.122(g) of the rule specifically applies to individual plan and TIP conformity determinations, and not to the entire nonattainment area. As a result, MPOs within a multiple-MPO area can rely upon their portion of the previous regional emissions analysis for the entire nonattainment area provided they are not changing their plans and TIPs in a manner that would trigger a new analysis per §93.122(g).

In addition, Part 2, Q&A #4, of EPA's July 2004 guidance states that "New or revised plans and TIPs, as well as significant changes to projects, could require a new regional emissions analysis (see §§93.104 and 93.122(g) of the conformity rule). Coordination of plan and TIP update cycles among MPOs in the same nonattainment area may minimize the number of new regional emissions analyses and conformity determinations that have to be completed."

Although this language does not specify whether a new analysis has to be conducted for the entire nonattainment area every time a plan/TIP conformity determination is made, it does acknowledge that in some cases a new analysis may not be necessary. In cases where an MPO is required to demonstrate conformity, but is not significantly changing its individual plan and TIP, the MPO may be able to rely upon §93.122(g) for their portion of the regional emissions analysis. The portions relying on a previous regional emissions analysis would then be combined with the new portion of the regional emissions analysis to demonstrate conformity. Note, however, if any portion of the regional emissions analysis relies on a previous analysis, the frequency requirements of §93.104(b) or (c) are not satisfied.

Q7. If one of the MPOs in the scenario in Q5. wants to update its Plan/TIP to add a new project (a change that would require a new regional emissions analysis), do the other two MPOs in the nonattainment area need to meet all of the public involvement requirements specified in the conformity rule, even though their plans and TIPs have not changed?

A. Since the other MPOs are only making new conformity determinations and are not making any changes to their plans and TIPs, the minimum public involvement requirements specified under §93.105(e) of the conformity rule would apply; requirements under DOT's transportation planning requirements, 23 CFR 450.316(b), would not apply in this case.

Section 93.105(e) of the conformity rule states, "Affected agencies making conformity determinations on transportation plans, programs, and projects shall establish a proactive public involvement process which provides opportunity for public review and comment by, at a minimum, providing reasonable public access to technical and policy information considered by the agency at the beginning of the public comment period and prior to taking formal action on a conformity determination for all transportation plan and TIPs, consistent with these requirements and those of 23 CFR 450.316(b)."

This provision requires every conformity determination to provide for public involvement that, at a minimum, allows for public review and comment. However, for conformity determinations that are not accompanied by a transportation planning action, an MPO would not need to satisfy the public involvement requirements under §450.316(b) of the planning regulations (including the requirement to hold a public hearing). Such transportation planning actions would include any change to a transportation plan, TIP, or project. In cases where MPOs are not conducting transportation planning actions, the MPO must satisfy only the minimum public involvement requirements stated in §93.105(e).

Q8: Do projects in a donut area have to be part of the TIP, or would they be found in the Statewide Transportation Improvement Program (STIP)? Do you have to determine conformity of the STIP?

A: Although MPOs can include projects in the donut area in their TIP, they are not required to do so for transportation planning purposes, even though the projects must be reflected in their regional emissions analysis. However, Federal projects in the donut area do have to be part of the STIP. The portion of the regional emissions analysis for the donut area must reflect the portion of the STIP within the donut area, as well as any regionally significant projects that are not included in the STIP. However, the transportation conformity rule does not require a conformity determination for the STIP itself.

Q9: Does a separate conformity determination need to be made for the donut area?

A: No. A separate conformity determination is not required for the donut area. Conformity determinations are required for metropolitan transportation plans and TIPs. In general, if these plans and TIPs cover a nonattainment or maintenance area with a donut area, then plan/TIP conformity determinations must be based on a regional emissions analysis that covers the entire nonattainment area, including the donut. For donut areas within multi-State nonattainment or maintenance areas, or areas with sub-area budgets, please see EPA's multi-jurisdictional guidance.

Q10: Can areas with sub-area budgets combine those budgets in order to meet conformity, or offset excess emissions in one sub-area with excess reductions in another?

A: No. The sub-area budget for that each sub-area must separately be met. See questions 5, 6, and 7 in Part 3 of EPA's multi-jurisdictional guidance for more information, as well as page 62196 of the preamble to the November 24, 1993 final rule (can be downloaded from the EPA website at: http://www.epa.gov/omswww/stateresources/transconf/conf-regs-c.htm), which states that the "conformity determination(s) must demonstrate consistency with each subregional emissions budget in the SIP."

Q11: In a multi-jurisdictional area, how do the various partners work together?

A: States are required to develop interagency consultation procedures and make them part of their SIP. These procedures should detail how multi-jurisdictional areas within that State demonstrate conformity, how and what data is analyzed, and the roles and responsibilities of all parties.

Q12: In a multi-state area with a single budget, how would this be detailed in each State's SIP?

A: State air agencies would have to work together to develop budgets. Each State would submit a SIP that contains the same budget for the entire area. Once this combined budget was found adequate or approved by EPA, it would have to be used in conformity determinations. The States must work together. Even though EPA would approve each State's SIP separately, they would each have the same budget. See questions 8 and 9 in Part 3 of EPA's multi-jurisdictional guidance for more information.

F. Conformity under the PM2.5 Standard

Q1: What on-road emissions may contribute to PM2.5 pollution?

A: PM2.5 is made up of direct pollutant emissions from vehicle tailpipes and brake and tire wear, as well as reentrained road dust from paved and unpaved roads and construction dust emissions from highway and transit construction. In addition, PM2.5 can also be formed from precursor emissions of oxides of nitrogen (NOx), volatile organic compounds (VOCs), sulfur oxides (SOx), and ammonia (NH3). See EPA's May 6, 2005 final rule for more information regarding when PM2.5 precursor emissions are considered in regional analyses in PM2.5 nonattainment and maintenance areas.

Q2: When the Transportation Conformity Rule refers to "reentrained road dust," does this refer to fugitive dust from paved and unpaved roads?

A: Yes. Reentrained road dust includes fugitive dust from both paved and unpaved roads. Therefore, if road dust is required to be analyzed for a conformity determination, the analysis must include dust from both paved and unpaved roads.

Q3: How is construction dust treated differently than road dust?

A: As required by 40 CFR 93.122(f), construction dust may need to be included in the regional emissions analysis, if a SIP identifies such dust as a significant contributor to the PM2.5 nonattainment problem. So construction dust will never be required to be analyzed for PM2.5 conformity prior to a PM2.5 SIP. However, with road dust, the air agency or EPA can make a finding that it is a significant contributor to the PM2.5 problem ahead of the SIP. Therefore, some PM2.5 areas may be required to consider road dust in PM2.5 regional emissions analyses if such a finding is made prior to the PM2.5 SIP. See Section X. of the July 1, 2004 rulemaking (69 FR 40035-40036) for more information.

Q4: Do analysis requirements for construction dust apply only to transportation projects, or to other things like shopping malls?

A: When construction dust must be analyzed for a conformity determination, it should only include construction dust from highway and transit projects.

Q5: Are exhaust emissions from construction equipment included in conformity analyses?

A: No. Construction equipment tailpipe emissions should not be included in transportation conformity analyses.

Q6: Do all PM2.5 areas have to develop budgets for all PM2.5 precursor pollutants?

A: No. If through the SIP development process, on-road emissions of one or more precursors are determined to be a significant contributor to the PM2.5 nonattainment problem, an emissions budget for each of the relevant precursors must be established in the SIP. Alternatively, if through the SIP development process, emissions of one or more precursors are found to be insignificant, the PM2.5 SIP would not establish motor vehicle emissions budgets for such precursors, and regional emissions analyses for such precursors would not be required for subsequent conformity determinations. Please see the May 6, 2005 final rule for more information, available at: http://www.epa.gov/fedrgstr/EPA-AIR/2005/May/Day-06/a9086.htm.

Q7: How is transportation conformity determined in noncontiguous PM2.5 nonattainment areas?

A: Noncontiguous PM2.5 nonattainment areas are areas that contain "satellite portions" that are not contiguous with the main portion of the nonattainment area. These satellite areas are designated as part of the overall nonattainment area because they have a point source which contributes, via transport, to the air quality problems of the main geographic portion of the PM2.5 nonattainment area.

The satellite portions of noncontiguous PM2.5 nonattainment areas should be treated as donut areas for transportation conformity purposes. Section 93.101 of the conformity rule defines "donut areas" as "geographic areas outside a metropolitan planning area boundary, but inside the boundary of a nonattainment or maintenance area that contains any part of a metropolitan area(s). These areas are not isolated rural nonattainment and maintenance areas."

Transportation conformity guidance for donut areas is provided in EPA's "Companion Guidance for the July 1, 2004, Final Transportation Conformity Rule: Conformity Implementation in Multi-jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality Standards." (See, in particular, Question 7 in Part 2 of the guidance.) This guidance document is available at: www.epa.gov/otaq/stateresources/transconf/policy.htm#require.

G. Conformity SIPs

Q1: In implementing the July 1, 2004 rulemaking, how are areas with approved conformity SIPs affected?

A: On November 18, 2004, EPA provided Conformity SIP Guidance. This guidance will help areas that have approved conformity SIPs know which provisions of the July 1, 2004, conformity rule amendments apply immediately and which provisions cannot apply until conformity SIPs are revised. It also includes information on other aspects of conformity SIPs. It is available at: http://www.epa.gov/otaq/stateresources/transconf/policy.htm.

H. Transportation Planning

Q1: For an MPO that has previously been attainment and subject to the 5-year plan update requirement, but is now nonattainment under the 8-hour ozone and/or PM2.5 standards, how do they transition to the 3-year plan/conformity update cycle?

A: The MPO must demonstrate conformity of its transportation plan and TIP within one year of the effective date of the nonattainment designation (June 15, 2004 for 8-hour ozone and April 5, 2005 for PM2.5). If an area has a valid plan in place (i.e., within the 5-year planning cycle for attainment areas), the area can demonstrate conformity on their existing plan provided that they meet all other requirements. However, the conformity determination will only be good for the rest of the life of the plan (i.e., if less than 3 years left in the plan, the plan will expire/lapse on its 5 year scheduled update) or 3 years after the conformity determination, whichever comes first. Alternatively, they can make a conformity determination on a brand new plan by the end of the grace period which will start the 3-year clock.

Q2: For an MPO that has previously been nonattainment or maintenance for the 1-hour standard and subject to the 3-year plan/conformity update requirement, but will now be attainment for all pollutants after the 1-hour standard is revoked, how do they transition to the 5-year plan update cycle?

A: Once the 1-hour standard is revoked, the 5-year plan update cycle will apply from the date of the most recent MPO plan adoption (not, the most recent FHWA/FTA conformity determination). This is consistent with the May 21, 2001 FHWA/FTA guidance on "Clarification of Plan Requirements in Nonattainment and Maintenance Areas" (http://www.fhwa.dot.gov//environment/air_quality/conformity/policy_and_guidance/cprnmamemo.cfm).

Q3: For an MPO that is a newly designated urbanized area and designated nonattainment under the 8-hour ozone standard, do they need to have a conforming plan and TIP in place by June 15, 2005?

A: No. The FAQs for Applying 2000 Census Data to Urbanized and Urban Areas (http://www.fhwa.dot.gov/policyinformation/hpms.cfm) states that MPOs in newly designated urbanized areas will be given until 10/1/05 to establish a planning process meeting all the requirements of 23 CFR 450 and 49 CFR 613, including a plan and TIP. Therefore, a conforming plan and TIP would not need to be in place until 10/1/05. If there are no other MPOs within the nonattainment area, it would be treated as an isolated rural area until a conforming plan and TIP are in place (i.e., no new non-exempt projects could be approved without meeting conformity requirements for isolated rural areas). If there are other MPOs within the nonattainment area, then the newly urbanized area could be treated as a donut area until a conforming plan and TIP are in place.

The FAQs also have a question on conformity in nonattainment and maintenance areas for newly designated urbanized areas. However, this FAQ only applies to areas that were existing non-attainment or maintenance areas when the urbanized area was designated. Therefore the three-year time limit from designation requirement in that question that would result in an area having a conforming plan/TIP in place by May 1, 2005 would not apply.

Q4: If an MPO contains portions of more than one nonattainment/maintenance area, must it determine conformity of the different areas at the same time?

No. Clean Air Act section 176(c)(5) specifically states that conformity applies in nonattainment and maintenance areas. Therefore, and MPO that includes multiple nonattainment areas may determine conformity separately for the portion of its plan/TIP in each separate nonattainment or maintenance area. Ideally, the MPO should determine conformity of both portions of its plan/TIP at the same time. However, precedents have been set where this is not the case. In other words, conformity might be determined on the portion of the plan/TIP in one nonattainment area, but not in the other. Note, that the MPO must meet the transportation planning regulations for plans and TIPs in 23 CFR 450.

Updated: 03/08/2013
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