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Notes

40 C.F.R. §§ 93.155–93.160

6 sections in range

§93.155. Reporting requirements.

40 C.F.R. § 93.155

(a)
A Federal agency making a conformity determination under §§ 93.154 through 93.160 and §§ 93.162 through 93.164 must provide to the appropriate EPA Regional Office(s), State and local air quality agencies, any federally-recognized Indian tribal government in the nonattainment or maintenance area, and, where applicable, affected Federal land managers, the agency designated under section 174 of the Act and the MPO, a 30-day notice which describes the proposed action and the Federal agency's draft conformity determination on the action. If the action has multi-regional or national impacts (e.g., the action will cause emission increases in excess of the de minimis levels identified in § 93.153(b) in three or more of EPA's Regions), the Federal agency, as an alternative to sending it to EPA Regional Offices, can provide the notice to EPA's Office of Air Quality Planning and Standards.
(b)
A Federal agency must notify the appropriate EPA Regional Office(s), State and local air quality agencies, any federally-recognized Indian tribal government in the nonattainment or maintenance area, and, where applicable, affected Federal land managers, the agency designated under section 174 of the Clean Air Act and the MPO, within 30 days after making a final conformity determination under this subpart.
(c)
The draft and final conformity determination shall exclude any restricted information or confidential business information. The disclosure of restricted information and confidential business information shall be controlled by the applicable laws, regulations, security manuals, or executive orders concerning the use, access, and release of such materials. Subject to applicable procedures to protect restricted information from public disclosure, any information or materials excluded from the draft or final conformity determination or supporting materials may be made available in a restricted information annex to the determination for review by Federal and State representatives who have received appropriate clearances to review the information.
Notes, amendments, and revision history

Amendments

[75 FR 17275, Apr. 5, 2010]

Source

Source: 58 FR 63253, Nov. 30, 1993, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 58 FR 62235, Nov. 24, 1993, unless otherwise noted.

Amendments

[75 FR 17275, Apr. 5, 2010]

§93.156. Public participation.

40 C.F.R. § 93.156

(a)
Upon request by any person regarding a specific Federal action, a Federal agency must make available, subject to the limitation in paragraph (e) of this section, for review its draft conformity determination under § 93.154 with supporting materials which describe the analytical methods and conclusions relied upon in making the applicability analysis and draft conformity determination.
(b)
A Federal agency must make public its draft conformity determination under § 93.154 by placing a notice by prominent advertisement in a daily newspaper of general circulation in the area affected by the action and by providing 30 days for written public comment prior to taking any formal action on the draft determination. This comment period may be concurrent with any other public involvement, such as occurs in the National Environmental Policy Act (NEPA) process. If the action has multi-regional or national impacts (e.g., the action will cause emission increases in excess of the de minimis levels identified in § 93.153(b) in three or more of EPA's Regions), the Federal agency, as an alternative to publishing separate notices, can publish a notice in the Federal Register.
(c)
A Federal agency must document its response to all the comments received on its draft conformity determination under § 93.154 and make the comments and responses available, subject to the limitation in paragraph (e) of this section, upon request by any person regarding a specific Federal action, within 30 days of the final conformity determination.
(d)
A Federal agency must make public its final conformity determination under § 93.154 for a Federal action by placing a notice by prominent advertisement in a daily newspaper of general circulation in the area affected by the action within 30 days of the final conformity determination. If the action would have multi-regional or national impacts, the Federal agency, as an alternative, can publish the notice in the Federal Register.
(e)
The draft and final conformity determination shall exclude any restricted information or confidential business information. The disclosure of restricted information and confidential business information shall be controlled by the applicable laws, regulations or executive orders concerning the release of such materials.
Notes, amendments, and revision history

Amendments

[75 FR 17275, Apr. 5, 2010]

Source

Source: 58 FR 63253, Nov. 30, 1993, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 58 FR 62235, Nov. 24, 1993, unless otherwise noted.

Amendments

[75 FR 17275, Apr. 5, 2010]

§93.157. Reevaluation of conformity.

40 C.F.R. § 93.157

(a)
Once a conformity determination is completed by a Federal agency, that determination is not required to be re-evaluated if the agency has maintained a continuous program to implement the action; the determination has not lapsed as specified in paragraph (b) of this section; or any modification to the action does not result in an increase in emissions above the levels specified in § 93.153(b). If a conformity determination is not required for the action at the time NEPA analysis is completed, the date of the finding of no significant impact (FONSI) for an Environmental Assessment, a record of decision (ROD) for an Environmental Impact Statement, or a categorical exclusion determination can be used as a substitute date for the conformity determination date.
(b)
The conformity status of a Federal action automatically lapses 5 years from the date a final conformity determination is reported under § 93.155, unless the Federal action has been completed or a continuous program to implement the Federal action has commenced.
(c)
Ongoing Federal activities at a given site showing continuous progress are not new actions and do not require periodic re-determinations so long as such activities are within the scope of the final conformity determination reported under § 93.155.
(d)
If the Federal agency originally determined through the applicability analysis that a conformity determination was not necessary because the emissions for the action were below the limits in § 93.153(b) and changes to the action would result in the total emissions from the action being above the limits in § 93.153(b), then the Federal agency must make a conformity determination.
Notes, amendments, and revision history

Amendments

[75 FR 17276, Apr. 5, 2010]

Source

Source: 58 FR 63253, Nov. 30, 1993, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 58 FR 62235, Nov. 24, 1993, unless otherwise noted.

Amendments

[75 FR 17276, Apr. 5, 2010]

§93.158. Criteria for determining conformity of general Federal actions.

40 C.F.R. § 93.158

(a)
An action required under § 93.153 to have a conformity determination for a specific pollutant, will be determined to conform to the applicable SIP if, for each pollutant that exceeds the rates in § 93.153(b), or otherwise requires a conformity determination due to the total of direct and indirect emissions from the action, the action meets the requirements of paragraph (c) of this section, and meets any of the following requirements:
(1)
For any criteria pollutant or precursor, the total of direct and indirect emissions from the action are specifically identified and accounted for in the applicable SIP's attainment or maintenance demonstration or reasonable further progress milestone or in a facility-wide emission budget included in a SIP in accordance with § 93.161;
(2)
For precursors of ozone, nitrogen dioxide, or PM, the total of direct and indirect emissions from the action are fully offset within the same nonattainment or maintenance area (or nearby area of equal or higher classification provided the emissions from that area contribute to the violations, or have contributed to violations in the past, in the area with the Federal action) through a revision to the applicable SIP or a similarly enforceable measure that effects emissions reductions so that there is no net increase in emissions of that pollutant;
(3)
For any directly-emitted criteria pollutant, the total of direct and indirect emissions from the action meets the requirements:
(i)
Specified in paragraph (b) of this section, based on areawide air quality modeling analysis and local air quality modeling analysis; or
(ii)
Meet the requirements of paragraph (a)(5) of this section and, for local air quality modeling analysis, the requirement of paragraph (b) of this section;
(4)
For CO or directly emitted PM—
(i)
Where the State agency primarily responsible for the applicable SIP determines that an areawide air quality modeling analysis is not needed, the total of direct and indirect emissions from the action meet the requirements specified in paragraph (b) of this section, based on local air quality modeling analysis; or
(ii)
Where the State agency primarily responsible for the applicable SIP determines that an areawide air quality modeling analysis is appropriate and that a local air quality modeling analysis is not needed, the total of direct and indirect emissions from the action meet the requirements specified in paragraph (b) of this section, based on areawide modeling, or meet the requirements of paragraph (a)(5) of this section; or
(5)
For ozone or nitrogen dioxide, and for purposes of paragraphs (a)(3)(ii) and (a)(4)(ii) of this section, each portion of the action or the action as a whole meets any of the following requirements:
(i)
Where EPA has approved a revision to the applicable implementation plan after the area was designated as nonattainment and the State or Tribe makes a determination as provided in paragraph (a)(5)(i)(A) of this section or where the State or Tribe makes a commitment as provided in paragraph (a)(5)(i)(B) of this section:
(A)
The total of direct and indirect emissions from the action (or portion thereof) is determined and documented by the State agency primarily responsible for the applicable SIP to result in a level of emissions which, together with all other emissions in the nonattainment (or maintenance) area, would not exceed the emissions budgets specified in the applicable SIP;
(B)
The total of direct and indirect emissions from the action (or portion thereof) is determined by the State agency responsible for the applicable SIP to result in a level of emissions which, together with all other emissions in the nonattainment (or maintenance) area, would exceed an emissions budget specified in the applicable SIP and the State Governor or the Governor's designee for SIP actions makes a written commitment to EPA which includes the following:

(1) A specific schedule for adoption and submittal of a revision to the SIP which would achieve the needed emission reductions prior to the time emissions from the Federal action would occur;

(2) Identification of specific measures for incorporation into the SIP which would result in a level of emissions which, together with all other emissions in the nonattainment or maintenance area, would not exceed any emissions budget specified in the applicable SIP;

(3) A demonstration that all existing applicable SIP requirements are being implemented in the area for the pollutants affected by the Federal action, and that local authority to implement additional requirements has been fully pursued;

(4) A determination that the responsible Federal agencies have required all reasonable mitigation measures associated with their action; and

(5) Written documentation including all air quality analyses supporting the conformity determination;

(C)
Where a Federal agency made a conformity determination based on a State's or Tribe's commitment under paragraph (a)(5)(i)(B) of this section and the State has submitted a SIP or TIP to EPA covering the time period during which the emissions will occur or is scheduled to submit such a SIP or TIP within 18 months of the conformity determination, the State commitment is automatically deemed a call for a SIP or TIP revision by EPA under section 110(k)(5) of the Act, effective on the date of the Federal conformity determination and requiring response within 18 months or any shorter time within which the State or Tribe commits to revise the applicable SIP;
(D)
Where a Federal agency made a conformity determination based on a State or tribal commitment under paragraph (a)(5)(i)(B) of this section and the State or Tribe has not submitted a SIP covering the time period when the emissions will occur or is not scheduled to submit such a SIP within 18 months of the conformity determination, the State or Tribe must, within 18 months, submit to EPA a revision to the existing SIP committing to include the emissions in the future SIP revision.
(ii)
The action (or portion thereof), as determined by the MPO, is specifically included in a current transportation plan and transportation improvement program which have been found to conform to the applicable SIP under 40 CFR part 51, subpart T, or 40 CFR part 93, subpart A;
(iii)
The action (or portion thereof) fully offsets its emissions within the same nonattainment or maintenance area (or nearby area of equal or higher classification provided the emissions from that area contribute to the violations, or have contributed to violation in the past, in the area with the Federal action) through a revision to the applicable SIP or an equally enforceable measure that effects emissions reductions equal to or greater than the total of direct and indirect emissions from the action so that there is no net increase in emissions of that pollutant;
(iv)
Where EPA has not approved a revision to the relevant SIP since the area was designated or reclassified, the total of direct and indirect emissions from the action for the future years (described in § 93.159(d)) do not increase emissions with respect to the baseline emissions:
(A)
The baseline emissions reflect the historical activity levels that occurred in the geographic area affected by the proposed Federal action during:

(1) The most current calendar year with a complete emission inventory available before an area is designated unless EPA sets another year; or

(2) The emission budget in the applicable SIP;

(3) The year of the baseline inventory in the PM-10 applicable SIP;

(B)
The baseline emissions are the total of direct and indirect emissions calculated for the future years (described in § 93.159(d)) using the historic activity levels (described in paragraph (a)(5)(iv)(A) of this section) and appropriate emission factors for the future years; or
(v)
Where the action involves regional water and/or wastewater projects, such projects are sized to meet only the needs of population projections that are in the applicable SIP.
(b)
The areawide and/or local air quality modeling analyses must—
(1)
Meet the requirements in § 93.159; and
(2)
Show that the action does not—
(i)
Cause or contribute to any new violation of any standard in any area; or
(ii)
Increase the frequency or severity of any existing violation of any standard in any area.
(c)
Notwithstanding any other requirements of this section, an action subject to this subpart may not be determined to conform to the applicable SIP unless the total of direct and indirect emissions from the action is in compliance or consistent with all relevant requirements and milestones contained in the applicable SIP, such as elements identified as part of the reasonable further progress schedules, assumptions specified in the attainment or maintenance demonstration, prohibitions, numerical emission limits, and work practice requirements.
(d)
Any analyses required under this section must be completed, and any mitigation requirements necessary for a finding of conformity must be identified before the determination of conformity is made.
Notes, amendments, and revision history

Amendments

[58 FR 63253, Nov. 30, 1993, as amended at 75 FR 17276, Apr. 5, 2010]

Source

Source: 58 FR 63253, Nov. 30, 1993, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 58 FR 62235, Nov. 24, 1993, unless otherwise noted.

Amendments

[58 FR 63253, Nov. 30, 1993, as amended at 75 FR 17276, Apr. 5, 2010]

§93.159. Procedures for conformity determinations of general Federal actions.

40 C.F.R. § 93.159

(a)
The analyses required under this subpart must be based on the latest planning assumptions.
(1)
All planning assumptions must be derived from the estimates of population, employment, travel, and congestion most recently approved by the MPO, or other agency authorized to make such estimates, where available.
(2)
Any revisions to these estimates used as part of the conformity determination, including projected shifts in geographic location or level of population, employment, travel, and congestion, must be approved by the MPO or other agency authorized to make such estimates for the urban area.
(b)
The analyses required under this subpart must be based on the latest and most accurate emission estimation techniques available as described below, unless such techniques are inappropriate. If such techniques are inappropriate, the Federal agency may obtain written approval from the appropriate EPA Regional Administrator for a modification or substitution, of another technique on a case-by-case basis or, where appropriate, on a generic basis for a specific Federal agency program.
(1)
For motor vehicle emissions, the most current version of the motor vehicle emissions model specified by EPA and available for use in the preparation or revision of SIPs in that State must be used for the conformity analysis as specified in paragraphs (b)(1)(i) and (ii) of this section:
(i)
The EPA must publish in the Federal Register a notice of availability of any new motor vehicle emissions model; and
(ii)
A grace period of 3 months shall apply during which the motor vehicle emissions model previously specified by EPA as the most current version may be used unless EPA announces a longer grace period in the Federal Register. Conformity analyses for which the analysis was begun during the grace period or no more than 3 months before the Federal Register notice of availability of the latest emission model may continue to use the previous version of the model specified by EPA.
(2)
For non-motor vehicle sources, including stationary and area source emissions, the latest emission factors specified by EPA in the “Compilation of Air Pollutant Emission Factors” (AP-42, http://www.epa.gov/ttn/chiefs/efpac) must be used for the conformity analysis unless more accurate emission data are available, such as actual stack test data from the stationary sources which are part of the conformity analysis.
(c)
The air quality modeling analyses required under this subpart must be based on the applicable air quality models, data bases, and other requirements specified in the most recent version of the “Guideline on Air Quality Models.” (Appendix W to 40 CFR part 51).
(1)
The guideline techniques are inappropriate, in which case the model may be modified or another model substituted on a case-by-case basis or, where appropriate, on a generic basis for a specific Federal agency program; and
(2)
Written approval of the EPA Regional Administrator is obtained for any modification or substitution.
(d)
The analyses required under this subpart must be based on the total of direct and indirect emissions from the action and must reflect emission scenarios that are expected to occur under each of the following cases:
(1)
The attainment year specified in the SIP, or if the SIP does not specify an attainment year, the latest attainment year possible under the Act; or
(2)
The last year for which emissions are projected in the maintenance plan;
(3)
The year during which the total of direct and indirect emissions from the action is expected to be the greatest on an annual basis; and
(4)
Any year for which the applicable SIP specifies an emissions budget.
Notes, amendments, and revision history

Amendments

[58 FR 63253, Nov. 30, 1993, as amended at 75 FR 17277, Apr. 5, 2010]

Source

Source: 58 FR 63253, Nov. 30, 1993, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 58 FR 62235, Nov. 24, 1993, unless otherwise noted.

Amendments

[58 FR 63253, Nov. 30, 1993, as amended at 75 FR 17277, Apr. 5, 2010]

§93.160. Mitigation of air quality impacts.

40 C.F.R. § 93.160

(a)
Any measures that are intended to mitigate air quality impacts must be identified and the process for implementation and enforcement of such measures must be described, including an implementation schedule containing explicit timelines for implementation.
(b)
Prior to determining that a Federal action is in conformity, the Federal agency making the conformity determination must obtain written commitments from the appropriate persons or agencies to implement any mitigation measures which are identified as conditions for making conformity determinations.
(c)
Persons or agencies voluntarily committing to mitigation measures to facilitate positive conformity determinations must comply with the obligations of such commitments.
(d)
In instances where the Federal agency is licensing, permitting or otherwise approving the action of another governmental or private entity, approval by the Federal agency must be conditioned on the other entity meeting the mitigation measures set forth in the conformity determination.
(e)
When necessary because of changed circumstances, mitigation measures may be modified so long as the new mitigation measures continue to support the conformity determination. Any proposed change in the mitigation measures is subject to the reporting requirements of § 93.156 and the public participation requirements of § 93.157.
(f)
Written commitments to mitigation measures must be obtained prior to a positive conformity determination and such commitments must be fulfilled.
(g)
After a State or Tribe revises its SIP or TIP and EPA approves that SIP revision, any agreements, including mitigation measures, necessary for a conformity determination will be both State or tribal and federally enforceable. Enforceability through the applicable SIP or TIP will apply to all persons who agree to mitigate direct and indirect emissions associated with a Federal action for a conformity determination.
Notes, amendments, and revision history

Amendments

[58 FR 63253, Nov. 30, 1993, as amended at 75 FR 17277, Apr. 5, 2010]

Source

Source: 58 FR 63253, Nov. 30, 1993, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 58 FR 62235, Nov. 24, 1993, unless otherwise noted.

Amendments

[58 FR 63253, Nov. 30, 1993, as amended at 75 FR 17277, Apr. 5, 2010]