Title 35: ENVIRONMENTAL PROTECTION
     
    SUBTITLE B: AIR POLLUTION
     
    CHAPTER II: ENVIRONMENTAL PROTECTION AGENCY
     
    PART
    255
     
    GENERAL CONFORMITY: CRITERIA AND PROCEDURES
     
    Section
    255.100 Purpose
    255.110 Federal Requirement
    255.120 Applicability
    255.140 Definitions
    255.150 Abbreviations
    255.160 Incorporations by Reference
    255.170 Activities Exempt from Conformity Analysis
    255.180 Conformity Analysis
    255.190 Reporting Requirements
    255.200 Public Participation
    255.210 Frequency of Conformity Determinations
    255.220 Criteria for Determining Conformity of General Federal Actions
    255.230 Procedures for Conformity Determinations of General Federal Actions
    255.240 Mitigation of Air Quality Impacts
     
    AUTHORITY: Authorized and implemented by Sections 4 and 9.1 of the Environmental
    Protection Act [415 ILCS 5/4 and 9.1].
     
    SOURCE: Adopted at 21 Ill. Reg. 3581, effective March 6, 1997
     
    Section 255.100 Purpose
     
    The purpose of this Part is to establish criteria and procedures substantively similar to 40 CFR
    part 51, Subpart W whereby Federal agencies required to make conformity determinations of
    Federal actions to Illinois= air quality implementations plans may consult and coordinate with
    the IEPA.
     
    Section 255.110 Federal Requirement
     
    a) Section 176(b)(1) of the Federal Clean Air Act (CAA) requires that any
    department, agency, instrumentality of the Federal Government that engages in,
    supports in any way, provides financial assistance for, licenses, permits, or
    approves any activity must conform to an applicable implementation plan.
     
    b) A Federal agency must make a determination that a Federal action conforms to
    the applicable implementation plan before the action is taken.
     
    c) Subsection (b) of this Section does not include Federal actions where either:

     
    1) A National Environmental Policy Act (NEPA) analysis was completed as
    evidenced by a final environmental assessment (EA), environmental
    impact statement (EIS), or finding of no significant impact (FONSI) that
    was prepared prior to January 31, 1994;
     
    2) Prior to January 31, 1994, an EA was commenced or a contract was
    awarded to develop the specific environmental analysis;
     
    3) Sufficient environmental analysis is completed by March 15, 1994, so that
    the Federal agency may determine that the Federal action is in conformity
    with the specific requirements and the purposes of the applicable SIP
    pursuant to the Federal agency's affirmative obligation under section
    176(c) of the CAA; or
     
    4) A written determination of conformity under section 176(c) of the CAA
    has been made by the Federal agency responsible for the Federal action by
    March 15, 1994.
     
    d) Notwithstanding any provisions of this Part, a determination that an action is in
    conformance with the applicable implementation plan does not exempt the action
    from any other requirements of the applicable implementation plan, the NEPA, or
    the CAA.
     
    Section 255.120 Applicability
     
    a) Conformity determinations for Federal actions related to transportation plans,
    programs, and projects developed, funded, or approved under Title 23 U.S.C. or
    the Federal Transit Act (49 U.S.C. 1601 et seq.) are not subject to the
    requirements of this Part.
     
    b) For Federal actions not covered by subsection (a) of this Section and not exempt
    pursuant to Section 255.170 of this Part, a conformity determination is required
    for each pollutant where the total of direct and indirect emissions in a
    nonattainment or maintenance area caused by a Federal action would equal or
    exceed any of the rates in subsection (b)(1) or (b)(2) of this Section:
     
    1) Nonattainment Areas:
     
    Tons/Year
    Ozone (VOC's or NOx):
    Serious NAA's 50
    Severe NAA's 25
    Extreme NAA's 10
     
    Other ozone NAA's outside an ozone

    transport region 100
     
    Marginal and moderate NAA's inside
    an ozone transport region:
    VOC
      
      
      
      
      
      
    50
    N0x 100
     
    Carbon monoxide:
    All NAA's 100
     
    SO2 or NO2:
    All NAA's 100
     
    PM-10:
    Moderate NAA's 100
    Serious NAA's 70
     
    Pb:
    All NAA's 25
     
    2) Maintenance Areas:
     
    Tons/Year
    Ozone (N0x) SO2 or NO2:
    All maintenance areas 100
     
    Ozone (VOC's):
    Maintenance areas inside an ozone
    transport region 50
    Maintenance areas outside an ozone
    transport region 100
     
    Carbon monoxide:
    All maintenance areas 100
     
    PM-10:
    All maintenance areas 100
     
    Pb:
    All maintenance areas 25
     
    Section 255.140 Definitions
     
    Terms used but not defined in this Part shall have the meaning given to them by the CAA and
    USEPA's regulations (40 CFR Chapter I) in that order of priority:
     

    AAffected Federal land manager@ means the Federal agency or the Federal official
    charged with direct responsibility for management of an area designated as Class I under
    the CAA (42 U.S.C. 7472) that is located within 100 km of the proposed Federal action.
     
    AApplicable implementation plan or applicable SIP@ means the portion (or portions) of
    the SIP or most recent revision thereof, which has been approved under section 110 of
    the CAA, or promulgated under section 110(c) of the CAA (Federal implementation
    plan), or promulgated or approved pursuant to regulations promulgated under section
    301(d) of the CAA and which implements the relevant requirements of the CAA.
     
    AAreawide air quality modeling analysis@ means an assessment on a scale that includes
    the entire nonattainment or maintenance area which uses an air quality dispersion model
    to determine the effects of emissions on air quality.
     
    ACause or contribute to a new violation@ means a Federal action that:
     
    Causes a new violation of a national ambient air quality standard (NAAQS) at a
    location in a nonattainment or maintenance area which would otherwise not be in
    violation of the standard during the future period in question if the Federal action
    were not taken; or
     
    Contributes, in conjunction with other reasonably foreseeable actions, to a new
    violation of a NAAQS at a location in a nonattainment or maintenance area in a
    manner that would increase the frequency or severity of the new violation.
     
    ACaused by@, as used in the terms "direct emissions" and "indirect emissions@,
    means emissions that would not otherwise occur in the absence of the Federal
    action.
     
    ACriteria pollutant or standard@ means any pollutant for which there is
    established a NAAQS at 40 CFR 50, incorporated by reference in Section
    255.160 of this Part.
     
    ADirect emissions@ means those emissions of a criteria pollutant or its
    precursors that are caused or initiated by the Federal action and occur at the same
    time and place as the action.
     
    AEmergency@ means a situation where extremely quick action on the part of the
    Federal agencies involved is needed and where the timing of such Federal
    activities makes it impractical to meet the requirements of this Part, such as
    natural disasters like hurricanes or earthquakes, civil disturbances such as terrorist
    acts, and military mobilizations.
     
    AEmissions budgets@ are those portions of the applicable SIP's projected
    emissions inventories that describe the levels of emissions (mobile, stationary,
    area, etc.) that provide for meeting reasonable further progress milestones,

    attainment, and/or maintenance for any criteria pollutant or its precursors.
     
    AEmissions offsets@, for purposes of Section 255.220 of this Part, are emissions
    reductions which are quantifiable, consistent with the applicable SIP attainment
    and reasonable further progress demonstrations, surplus to reductions required by,
    and credited to, other applicable SIP provisions, enforceable at both the State and
    Federal levels, and permanent within the timeframe specified by the program.
     
    AEmissions that a Federal agency has a continuing program responsibility for@
    means emissions that are specifically caused by an agency carrying out its
    authorities, and does not include emissions that occur due to subsequent activities,
    unless such activities are required by the Federal agency. Where an agency, in
    performing its normal program responsibilities, takes actions itself or imposes
    conditions that result in air pollutant emissions by a non-federal entity taking
    subsequent actions, such emissions are covered by the meaning of a continuing
    program responsibility.
     
    AFederal action@ means any activity engaged in by a department, agency, or
    instrumentality of the Federal government, or any activity that a department,
    agency or instrumentality of the Federal government supports in any way,
    provides financial assistance for, licenses, permits, or approves, other than
    activities related to transportation plans, programs, and projects developed,
    funded, or approved under 23 U.S.C. or the Federal Transit Act (49 U.S.C. 1601
    et seq.). Where the Federal action is a permit, license, or other approval for some
    aspect of a non-federal undertaking, the relevant activity is the part, portion, or
    phase or the non-Federal undertaking that requires the Federal permit, license, or
    approval.
     
    AFederal agency@ means, for purposes of this Part, a Federal department,
    agency, or instrumentality of the Federal government.
     
    AIncrease the frequency or severity of any existing violation of any standard in
    any area@ means to cause a nonattainment area to exceed a standard more often
    or to cause a violation at a greater concentration than previously existed and/or
    would otherwise exist during the future period in question, if the project were not
    implemented.
     
    "Indirect emissions@ means those emissions of a criteria pollutant or its
    precursors that:
     
    Are caused by the Federal action, but may occur later in time and/or may
    be farther removed in distance from the action itself but are still
    reasonably foreseeable; and
     
    The Federal agency can practicably control and will maintain control over
    due to a continuing program responsibility of the Federal agency.

     
    "Local air quality modeling analysis@ means an assessment of localized impacts
    on a scale smaller than the entire nonattainment or maintenance area, including,
    for example, congested roadway intersections and highways or transit terminals,
    which uses an air quality dispersion model to determine the effects of emissions
    on air quality.
     
    "Maintenance area@ means an area with a maintenance plan approved under
    section 175A of the CAA.
     
    "Maintenance plan@ means a revision to the applicable SIP, meeting the
    requirements of section 175A of the CAA.
     
    "Metropolitan Planning Organization (MPO)" means that organization designated
    as being responsible, together with the State, for conducting the continuing,
    cooperative, and comprehensive planning process under Section 134 of 23 U.S.C.
    134 and Section 1607 of the Federal Transit Act (49 U.S.C. 1607).
     
    "Milestone" has the meaning given in sections 82(g)(1) and 189(c)(1) of the
    CAA.
     
    ANational ambient air quality standards (NAAQS)@ means those standards
    established pursuant to section 109 of the CAA and include standards for carbon
    monoxide (CO), lead (Pb), nitrogen dioxide (NO2), ozone, particulate matter
    (PM-10), and sulfur dioxide (SO2).
     
    ANEPA@ means the National Environmental Policy Act of 1969, as amended
    (42 U.S.C. 4321 et seq.).
     
    ANonattainment Area (NAA)@ means an area designated as nonattainment under
    section 107 of the CAA and described in 40 CFR 81, incorporated by reference in
    Section 255.160 of this Part.
     
    APrecursors of a criteria pollutant" means:
     
    For ozone, nitrogen oxides (NOx) unless an area is exempted from NOx
    requirements under section 182(f) of the CAA, and volatile organic
    compounds (VOC); and
     
    For PM-10, those pollutants described in the PM-10 nonattainment area
    applicable SIP as significant contributors to the PM-10 levels.
     
    AReasonably foreseeable emissions" means projected future indirect emissions
    that are identified at the time the conformity determination is made; the location
    of such emissions is known and the emissions are quantifiable, as described and
    documented by the Federal agency based on its own information and after

    reviewing any information presented to the Federal agency.
     
    ARegional water and/or wastewater projects" means construction, operation, and
    maintenance of water or wastewater conveyances, water or wastewater treatment
    facilities, and water storage reservoirs which affect a large portion of a
    nonattainment or maintenance area.
     
    ARegionally significant action@ means a Federal action for which the direct and
    indirect emissions of any pollutant represent 10 percent (.10) or more of a
    nonattainment or maintenance area's emissions inventory for that pollutant.
     
    ATotal of direct and indirect emissions@ means the sum of direct and indirect
    emissions increases and decreases caused by the Federal action; i.e., the "net"
    emissions, considering all direct and indirect emissions. The portion of emissions
    which are exempt or presumed to conform under subsections (a) through (g) of
    Section 255.170 are not included in the total of direct and indirect emissions. The
    "total of direct and indirect emissions" includes emissions of criteria pollutants
    and emissions of precursors of criteria pollutants.
     
    Section 255.150 Abbreviations
     
    CAA Clean Air Act
    CERCLA Comprehensive Environmental Response, Compensation and
    Liability Act
    EA environmental assessment
    EIS environmental impact statement
    FONSI finding of no significant impact
    IEPA Illinois Environmental Protection Agency
    km kilometer
    MPO metropolitan planning organization
    mi mile
    NAA nonattainment area
    NAAQS National Ambient Air Quality Standard
    NEPA National Environmental Policy Act
    NSR New Source Review
    PSD Prevention Significant Deterioration
    SIP state implementation plan
    USEPA United States Environmental Protection Agency
     
    Section 255.160 Incorporations by Reference
     
    The following materials are incorporated by reference and do not contain any subsequent
    additions or amendments:
     
    a) Determining Conformity of General Federal Actions to State or Federal
    Implementation Plans, 40 CFR 51, Subpart W.

     
    b) National Primary and Secondary Ambient Air Quality Standards, 40 CFR 50
    (1995).
     
    c) Designations of Areas for Air Quality Purposes, 40 CFR 81 (1995).
     
    d) Compilation of Air Pollutant Emission Factors (AP-42) the Technical Support
    Division of OAQPS, EPA, MD-14, Research Triangle Park, NC 27711.
     
    e) AGuidelines on Air Quality Models@ Part 51 - Requirements for Preparation,
    Adoption and Submittal of Implementation Plans, 40 CFR 51, Appendix W, 61
    Fed. Reg. 41837 (August 12, 1996).
    .
    Section 255.170 Activities Exempt from Conformity Analysis
     
    The requirements of this Part shall not apply to:
     
    a) Actions where the total of direct and indirect emissions are below the emissions
    levels specified in subsections (b)(1) and (b)(2) of Section 255.120.
      
    b) The following actions which would result in no emissions increase or an increase
    in emissions that is clearly de minimis:
     
    1) Judicial and legislative proceedings.
     
    2) Continuing and recurring activities such as permit renewals where
    activities conducted will be similar in scope and operation to activities
    currently being conducted.
     
    3) Rulemaking and policy development and issuance.
     
    4) Routine maintenance and repair activities, including repair and
    maintenance of administrative sites, roads, trails, and facilities.
     
    5) Civil and criminal enforcement activities, such as investigations, audits,
    inspections, examinations, prosecutions, and the training of law
    enforcement personnel.
     
    6) Administrative actions such as personnel actions, organizational changes,
    debt management or collection, cash management, internal agency audits,
    program budget proposals, and matters relating to the administration and
    collection of taxes, duties and fees.
     
    7) The routine, recurring transportation of material and personnel.
     
    8) Routine movement of mobile assets, such as ships and aircraft, in home

    port reassignments and stations (when no new support facilities or
    personnel are required) to perform as operational groups and/or for repair
    or overhaul.
     
    9) Maintenance dredging and debris disposal where no new depths are
    required, applicable permits are secured, and disposal will be at an
    approved disposal site.
     
    10) Actions, such as the following, with respect to existing structures,
    properties, facilities and lands where future activities conducted will be
    similar in scope and operation to activities currently being conducted at
    the existing structures, properties, facilities, and lands; for example,
    relocation of personnel, disposition of federally-owned existing structures,
    properties, facilities, and lands, rent subsidies, operation and maintenance
    cost subsidies, the exercise of receivership or conservatorship authority,
    assistance in purchasing structures, and the production of coins and
    currency.
     
    11) The granting of leases, licenses such as for exports and trade, permits, and
    easements where activities conducted will be similar in scope and
    operation to activities currently being conducted.
     
    12) Planning, studies, and provision of technical assistance.
     
    13) Routine operation of facilities, mobile assets and equipment.
     
    14) Transfers of ownership, interests, and titles in land, facilities, and real and
    personal properties, regardless of the form or method of the transfer.
     
    15) The designation of empowerment zones, enterprise communities, or
    viticultural areas.
     
    16) Actions by any of the Federal banking agencies or the Federal Reserve
    Banks, including actions regarding charters, applications, notices, licenses,
    the supervision or examination of depository institutions or depository
    institution holding companies, access to the discount window, or the
    provision of financial services to banking organizations or to any
    department, agency or instrumentality of the United States.
     
    17) Actions by the Board of Governors of the Federal Reserve System or any
    Federal Reserve Bank to effect monetary or exchange rate policy.
     
    18) Actions that implement a foreign affairs function of the United States.
     
    19) Actions (or portions thereof) associated with transfers of land, facilities,
    title, and real properties through an enforceable contract or lease

    agreement where the delivery of the deed is required to occur promptly
    after a specific, reasonable condition is met, such as promptly after the
    land is certified as meeting the requirements of the Comprehensive
    Environmental Response, Compensation, and Liability Act (CERCLA),
    and where the Federal agency does not retain continuing authority to
    control emissions associated with the lands, facilities, title, or real
    properties.
     
    20) Transfers of real property, including land, facilities, and related personal
    property from a Federal entity to another Federal entity and assignments
    of real property, including land, facilities, and related personal property
    from a Federal entity to another Federal entity for subsequent deeding to
    eligible applicants.
     
    21) Actions by the Department of the Treasury to effect fiscal policy and to
    exercise the borrowing authority of the United States.
     
    c) The following actions where the emissions are not reasonably foreseeable:
     
    1) Initial Outer Continental Shelf lease sales which are made on a broad scale
    and are followed by exploration and development plans on a project level.
     
    2) Electric power marketing activities that involve the acquisition, sale and
    transmission of electric energy.
     
    d) Actions which implement a decision to conduct or carry out a conforming
    program such as prescribed burning actions which are consistent with a
    conforming land management plan.
     
    e) Notwithstanding the other requirements of this Part, a conformity determination is
    not required for the following Federal actions (or portion thereof):
     
    1) The portion of an action that includes major new or modified stationary
    sources that require a permit under the new source review (NSR) program
    (section 173 of the CAA) or the prevention of significant deterioration
    (PSD) program (title I, part C of the CAA).
     
    2) Actions in response to emergencies or natural disasters such as hurricanes,
    earthquakes, etc., which are commenced on the order of hours or days
    after the emergency or disaster and, if applicable, which meet the
    requirements of subsection (f) of this Section.
     
    3) Research, investigations, studies, demonstrations, or training (other than
    those exempted under subsection (b) of this Section), where no
    environmental detriment is incurred and/or where the particular action
    furthers air quality research.

     
    4) Alteration and additions of existing structures as specifically required by
    new or existing applicable environmental legislation or environmental
    regulations (e.g., hush houses for aircraft engines and scrubbers for air
    emissions).
     
    5) Direct emissions from remedial and removal actions carried out under
    CERCLA and associated regulations to the extent such emissions either
    comply with the substantive requirements of the PSD/NSR permitting
    program or are exempted from other environmental regulation under the
    provisions of CERCLA and applicable regulations issued under CERCLA.
     
    f) Federal actions which are part of a continuing response to an emergency or
    disaster under subsection (e)(2) of this Section and which are to be taken more
    than six months after the commencement of the response to the emergency or
    disaster under subsection (e)(2) of this Section are exempt from the requirements
    of this Part only if:
     
    1) The Federal agency taking the actions makes a written determination that,
    for a specified period not to exceed an additional six months, it is
    impractical to prepare the conformity analyses which would otherwise be
    required and the actions cannot be delayed due to overriding concerns for
    public health and welfare, national security interests and foreign policy
    commitments; or
     
    2) For actions which are to be taken after those actions covered by subsection
    (f)(1) of this Section, the Federal agency makes a new determination as
    provided in subsection (f)(1) of this Section.
    g) Notwithstanding other requirements of this Part, actions specified by individual
    Federal agencies that have met the criteria set forth in either subsection (h)(1)(A)
    or (B) of this Section and the procedures set forth in subsection (i) of this Section
    are presumed to conform, except as provided in subsection (j) of this Section.
     
    h) The Federal agency must meet the criteria for establishing activities that are
    presumed to conform by fulfilling the requirements set forth in either subsection
    (1) or (2) of this Subsection(h):
     
    1) The Federal agency must clearly demonstrate using methods consistent
    with this Part that the total of direct and indirect emissions from the type
    of activities which would be presumed to conform would not:
     
    A) Cause or contribute to any new violation of any standard in any
    area;
     
    B) Interfere with provisions in the applicable SIP for maintenance of
    any standard;

     
    C) Increase the frequency or severity of any existing violation of any
    standard in any area; or
     
    D) Delay timely attainment of any standard or any required interim
    emission reductions or other milestones in any area including,
    where applicable, emission levels specified in the applicable SIP
    for purposes of:
     
    i) A demonstration of reasonable further progress;
     
    ii) A demonstration of attainment; or
     
    iii) A maintenance plan; or
     
    2) The Federal agency must provide documentation that the total of direct
    and indirect emissions from such future actions would be below the
    emission rates for a conformity determination that are established in
    Section 255.120(b)(1) and (2) of this Part, based, for example, on similar
    actions taken over recent years.
     
    i) In addition to meeting the criteria for establishing exemptions set forth in
    subsection (h)(1) or (h)(2) of this Section, the following procedures must also be
    complied with to presume that activities will conform:
     
    1) The Federal agency must identify through publication in the Federal
    Register its list of proposed activities that are presumed to conform and
    the basis for the presumptions;
     
    2) The Federal agency must notify USEPA Region V Office, IEPA, local air
    quality agencies and, where applicable, the agency designated under
    section 174 of the CAA and the MPO and provide at least 30 days for the
    public to comment on the list of proposed activities presumed to conform;
     
    3) The Federal agency must document its response to all the comments
    received and make the comments, response, and final list of activities
    available to the public upon request; and
     
    4) The Federal agency must publish the final list of such activities in the
    Federal Register.
     
    j) Notwithstanding the other requirements of this Part, when the total of direct and
    indirect emissions of any pollutant from a Federal action does not equal or exceed
    the rates specified in Sections 255.120 (b)(1) or (2) of this Part, but represents ten
    percent (.10) or more of a nonattainment or maintenance area's total emissions of
    that pollutant, the action is defined as a regionally significant action and the

    requirements of Sections 255.110 and 255.190 through 255.240 of this Part shall
    apply for the Federal action.
     
    k) Where an action otherwise presumed to conform under subsection (g) of this
    Section is a regionally significant action or does not in fact meet one of the
    criteria in subsection (h)(1) of this Section, that action shall not be presumed to
    conform and the requirements of Sections 255.110 and 255.190 through 255.240
    of this Part shall apply for the Federal action.
     
    l) The provisions of this Part shall apply in all nonattainment and maintenance
    areas.
     
    Section 255.180 Conformity Analysis
     
    Any Federal department, agency, or instrumentality of the Federal government taking an action
    subject to the requirements of this Part must make its own conformity determination consistent
    with the requirements of this Part. In making its conformity determination, a Federal agency
    must consider comments from any interested parties. Where multiple Federal agencies have
    jurisdiction for various aspects of a project, a Federal agency may choose to adopt the analysis of
    another Federal agency or develop its own analysis in order to make its conformity
    determination.
     
    Section 255.190 Reporting Requirements
     
    a) A Federal agency making a conformity determination under Section 255.220 of
    this Part must provide to appropriate USEPA Region V Office, IEPA, local air
    quality agencies and, where applicable, affected Federal land managers, the
    agency designated under section 174 of the CAA, and the MPO a 30 day notice
    which describes the proposed action and the Federal agency's draft conformity
    determination on the action.
     
    b) A Federal agency must notify USEPA Region V Office, IEPA, local air quality
    agencies and, where applicable, affected Federal land managers, the agency
    designated under section 174 of the CAA and the MPO within 30 days after
    making a final conformity determination under Section 255.220 of this Part.
     
    Section 255.200 Public Participation
     
    a) Upon request by any person regarding a specific Federal action, a Federal agency
    must make available for review its draft conformity determination under Section
    255.220 of this Part 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
    Section 255.220 of this Part 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 NEPA process.
     
    c) A Federal agency must document its response to all the comments received on its
    draft conformity determination under Section 255.220 of this Part, and make the
    comments and responses available, upon request by any person regarding a
    specific Federal action, within 30 days after the final conformity determination.
     
    d) A Federal agency must make public its final conformity determination under
    Section 255.220 of this Part 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 after the final conformity determination.
     
    Section 255.210 Frequency of Conformity Determinations
     
    a) The conformity status of a Federal action shall lapse 5 years from the date a final
    conformity determination is reported under Section 255.190 of this Part, unless
    the Federal action has been completed or a continuous program has been
    commenced to implement that Federal action within a reasonable time.
     
    b) Ongoing Federal activities at a given site showing continuous progress are not
    new actions and do not require periodic redeterminations so long as such
    activities are within the scope of the final conformity determination reported
    under Section 255.190 of this Part.
     
    c) If, after the conformity determination is made, the Federal action is changed so
    that there is an increase in the total of direct and indirect emissions above the
    levels in Section 255.120(b)(1) and (2) of this Part, a new conformity
    determination is required.
     
    Section 255.220 Criteria for Determining Conformity of General Federal Actions
     
    a) An action required under Section 255.120(b)(1) and (2) of this Part 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 Section
    255.120(b)(1) and (2) of this Part, or otherwise requires a conformity
    determination due to the total of direct and indirect emissions from the action, the
    action meets the requirements of subsection (c) of this Section, and meets any of
    the following requirements:
     
    1) For any criteria pollutant, 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;
     

    2) For ozone or nitrogen dioxide, the total of direct and indirect emissions
    from the action are fully offset within the same nonattainment or
    maintenance area through a revision to the applicable SIP or a similarly
    enforceable measure that effects emission reductions so that there is no net
    increase in emissions of that pollutant;
     
    3) For any criteria pollutant, except ozone and nitrogen dioxide, the total of
    direct and indirect emissions from the action meets the requirements
    specified in:
     
    A) Subsection (b) of this Section, based on areawide air quality
    modeling analysis and local air quality modeling analysis; or
     
    B) Subsection (a)(5) of this Section and, for local air quality modeling
    analysis, the requirement of subsection (b) of this Section;
     
    4) For CO or PM-10:
     
    A) Where the IEPA advises that an areawide air quality modeling
    analysis is not needed, the total of direct and indirect emissions
    from the action meets the requirements specified in subsection (b)
    of this Section, based on local air quality modeling analysis; or
     
    B) Where the IEPA advises 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 meets the requirements specified in subsection (b)
    of this Section, based on areawide modeling, or meets the
    requirements of subsection (a)(5) of this Section; or
     
    5) For ozone or nitrogen dioxide, and for purposes of subsections (a)(3)(B)
    and (a)(4)(B) of this Section, each portion of the action or the action as a
    whole meets any of the following requirements:
     
    A) Where USEPA has approved a revision to an area's attainment or
    maintenance demonstration after 1990 and IEPA makes a
    determination as provided in subsection (a)(5)(A)(i) of this Section
    or where the State makes a commitment as provided in subsection
    (a)(5)(A)(ii)of this Section:
     
    i) The total of direct and indirect emissions from the action
    (or portion thereof) is determined and documented by IEPA
    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;

     
    ii) The total of direct and indirect emissions from the action
    (or portion thereof) is determined by IEPA 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
    Director of IEPA makes a written commitment to USEPA
    which includes the following:
     
    a 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;
     
    identification of 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;
     
    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;
     
    a determination that the responsible Federal agencies have
    required all reasonable mitigation measures associated with
    their action; and
     
    written documentation including all air quality analyses
    supporting the conformity determination;
     
    B) 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;
     
    C) The action (or portion thereof) fully offsets its emissions within the
    same nonattainment or maintenance area through a revision to the
    applicable SIP or an equally enforceable measure that effects
    emission 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;
     
    D) Where USEPA has not approved a revision to the relevant SIP

    attainment or maintenance demonstration since 1990, the total of
    direct and indirect emissions from the action for the future years
    (described in Section 255.230 of this Part) do not increase
    emissions with respect to the baseline emissions:
     
    i) The baseline emissions reflect the historical activity levels
    that occurred in the geographic area affected by the
    proposed Federal action during:
     
    calendar year 1990;
     
    the calendar year that is the basis for the classification (or,
    where the classification is based on multiple years, the
    most representative year), if a classification is promulgated
    in 40 CFR part 81, incorporated by reference in Section
    255.160 of this Part; or
     
    the year of the baseline inventory in the PM-10 applicable
    SIP;
     
    ii) The baseline emissions are the total of direct and indirect
    emissions calculated for the future years (described in
    Section 255.230(d) of this Part using the historic activity
    levels (described in subsection (a)(5)(D)(i) of this Section)
    and appropriate emission factors for the future years; or
     
    E) 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 Section 255.230 of this Part; and
     
    2) Show that the action does not:
       
    A) Cause or contribute to any new violation of any standard in any area; or
     
    B) 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 Part 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.
     
    Section 255.230 Procedures for Conformity Determinations of General Federal Actions
     
    a) The analyses required under this Part 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, regional
    planning commission 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, shall be developed in consultation with the
    regional planning commission, MPO or other agency authorized to make such
    estimates for the urban area.
     
    b) The analyses required under this Part 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 and written approval of the USEPA
    Regional Administrator is obtained for any modification or substitution, they may be
    modified or another technique substituted on a case-by-case basis or, where appropriate,
    on a generic basis for a specific Federal agency program. Any modification and
    substitution shall be done in consultation with IEPA and USEPA.
     
    1) For motor vehicle emissions, the most current version of the motor vehicle
    emissions model specified by USEPA and available for use in the preparation or
    revision of SIPs in this State must be used for the conformity analysis as specified
    in subsections (b)(1)(A) and (B) of this Section:
     
    A) The USEPA must publish in the Federal Register a notice of availability
    of any new motor vehicle emissions model; and
     
    B) A grace period of 3 months shall apply during which the motor vehicle
    emissions model previously specified by USEPA as the most current
    version may be used. Conformity analyses for which the analysis was
    begun during the grace period or no more than 3 years before the Federal
    Register notice of availability of the latest emission model may continue
    to use the previous version of the model specified by USEPA.
     
    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)" as incorporated by reference in Section 255.160 of
    this Part must be used for the conformity analysis unless more accurate emission
    data are available, such as actual stack test data from stationary sources which are
    part of the conformity analysis.
     
    c) Any air quality modeling analyses necessary to demonstrate conformity shall 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@ Part 51 - Requirements for
    Preparation, Adoption, and Submittal of Implementation Plans, 40 CFR 51, Appendix W,
    61 Fed. Reg. 41837 (August 12, 1996) incorporated by reference in Section 255.160 of
    this Part, unless:
     
    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) Any modification of substitution shall be done in consultation with USEPA.
     
    d) The analyses required under this Part, except Section 255.220(a)(1) of this Part, 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 CAA mandated attainment year or, if applicable, the farthest year for which
    emissions are projected in the maintenance plan;
     
    2) 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
     
    3) Any year for which the applicable SIP specifies an emissions budget.
     
    Section 255.240 Mitigation of Air Quality Impacts
     
    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 time lines for implementation.
    Such measures shall become an integral component of the Federal action being
    determined to conform. Failure to implement committed mitigation measures will
    jeopardize the conformity determination and expose the Federal agency to enforcement
    provisions of the CAA.
     
    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 assure the implementation of 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 binding the entity to implement 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 Section 255.190 of this Part and the public participation
    requirements of Section 255.200 of this Part.
     

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