Air Program Class 1 Redesignation

The Fond du Lac Band of Lake Superior Chippewa is proud to announce our intent to re-designate the Reservation Air Shed from Class II to Class I. In the sections below, you will have the opportunity to learn more about the benefits of our effort to protect public health and the environment from the harmful effects of air pollution. This effort will greatly benefit reservation resources; however, the benefit does not stop there. The region’s residents, communities, businesses, heritage, not to mention flora and fauna will all greatly benefit from this effort to protect the natural environment and everything that depends on it.

The Clean Air Act provides the opportunity for states and tribes to redesignate their lands from Class II to Class I, through an application to the Environmental Protection Agency. All areas of the country are Class II except for national parks, forests, and monuments, they are Mandatory Class I areas. State and Tribal lands may be reclassified as Class I lands if the individual State or Tribe chooses to do so. Class I status means that only a limited amount of pollution from new, major sources will be allowed after a certain baseline date. While Class II limits new pollution, the Class I standards offer even more protection. Existing sources will not be affected (unless they make a major modification to their operations), nor will new sources that are below major source thresholds. While a Class III category does exist, there are no Class III areas in the nation, as this would allow air quality levels that would be unhealthy. The National Ambient Air Quality Standards (NAAQS) set standards that protect human health.

Class 1 Redesignation

For questions and comments:

Class I Requirements - 40 CFR-52-21(g)


(1) All areas (except as otherwise provided under paragraph (e) of this section) are designated Class II as of December 5, 1974. Redesignation (except as otherwise precluded by paragraph (e) of this section) may be proposed by the respective States or Indian Governing Bodies, as provided below, subject to approval by the Administrator as a revision to the applicable State implementation plan.

(2) The Tribe may submit to the Administrator a proposal to redesignate areas of the State Class I or Class II provided that:

  • (i) At least one public hearing has been held in accordance with procedures established in § 51.102 of this chapter;
  • (ii) Other States, Indian Governing Bodies, and Federal Land Managers whose lands may be affected by the proposed redesignation were notified at least 30 days prior to the public hearing;
  • (iii) A discussion of the reasons for the proposed redesignation, including a satisfactory description and analysis of the health, environmental, economic, social and energy effects of the proposed redesignation, was prepared and made available for public inspection at least 30 days prior to the hearing and the notice announcing the hearing contained appropriate notification of the availability of such discussion;
  • (iv) Prior to the issuance of notice respecting the redesignation of an area that includes any Federal lands, the State has provided written notice to the appropriate Federal Land Manager and afforded adequate opportunity (not in excess of 60 days) to confer with the State respecting the redesignation and to submit written comments and recommendations. In redesignating any area with respect to which any Federal Land Manager had submitted written comments and recommendations, the State shall have published a list of any inconsistency between such redesignation and such comments and recommendations (together with the reasons for making such redesignation against the recommendation of the Federal Land Manager); and
  • (v) The State has proposed the redesignation after consultation with the elected leadership of local and other substate general purpose governments in the area covered by the proposed redesignation.

(3) Any area other than an area to which paragraph (e) of this section refers may be redesignated as Class III if --

  • (i) The redesignation would meet the requirements of paragraph (g)(2) of this section;
  • (ii) RESERVED
  • (iii) The redesignation would not cause, or contribute to, a concentration of any air pollutant which would exceed any maximum allowable increase permitted under the classification of any other area or any national ambient air quality standard; and
  • (iv) Any permit application for any major stationary source or major modification, subject to review under paragraph (l) of this section, which could receive a permit under this section only if the area in question were redesignated as Class III, and any material submitted as part of that application, were available insofar as was practicable for public inspection prior to any public hearing on redesignation of the area as Class III.

(4) Lands within the exterior boundaries of Indian Reservations may be redesignated only by the appropriate Indian Governing Body. The appropriate Indian Governing Body may submit to the Administrator a proposal to redesignate areas Class I, Class II, or Class III: Provided, That:

  • (i) The Indian Governing Body has followed procedures equivalent to those required of a State under paragraphs (g)(2), (g)(3)(iii), and (g)(3)(iv) of this section; and
  • (ii) Such redesignation is proposed after consultation with the State(s) in which the Indian Reservation is located and which border the Indian Reservation.

(5) The Administrator shall disapprove, within 90 days of submission, a proposed redesignation of any area only if he finds, after notice and opportunity for public hearing, that such redesignation does not meet the procedural requirements of this paragraph or is inconsistent with paragraph (e) of this section. If any such disapproval occurs, the classification of the area shall be that which was in effect prior to the redesignation which was disapproved.

(6) If the Administrator disapproves any proposed redesignation, the State or Indian Governing Body, as appropriate, may resubmit the proposal after correcting the deficiencies noted by the Administrator.

Fond du Lac Class I Technical Reports and Supporting Documentation

FDL Class I Redesignation Technical Report, July 2014

Economic Impact of FDL Class 1 Redesignation Report, April 2012

Energy Impact Analysis in Support of Class I Redesignation Requests, August 2011

Class I for Tribes: Why a tribe might pursue this designation

The principal reason for redesignation to Class 1 is to obtain more environmental protection for reservation air quality and tribal resources. First, air quality is not allowed to deteriorate by more than Prevention of Significant Deterioration (PSD) increment allows for a Class 1 area. Secondly, a PSD permit may require the addition of more efficient emission controls.

Redesignation to Class I provides a tribe with an opportunity to:

  • Exercise certain controls over protection of reservation air resources.
  • Assert tribal sovereignty.
  • Protect the reservation from certain air quality impacts arising from emission sources off reservation.
  • Build tribal capacity in the implementation of the Act.
  • Receive notice of all PSD permit applications for sources located outside the re-designated reservation that are likely to affect a Class I area.
  • Protect air quality through the use of the Class I increments and any Air Quality Related Values (AQRVs) defined by the tribe, with a potential recourse to dispute resolution pursuant to CAA Section 164(e) if issues regarding the impact of a proposed state permitting action cannot be resolved.

Basics of Increment

Prevention of Significant Deterioration (PSD) is defined as deterioration relative to a baseline condition

  • PSD accounted by increment consumption


  • The amount of additional pollution that is allowed over the baseline concentration in a PSD area
  • Called "maximum allowable increases" in the Act
  • There are different increments for 3-hour, 24-hour and annual emission-averaging time periods (measured as increases of ambient concentrations, in mg/m3)Most stringent for Class I, less for Class II, least for Class III (if any areas ever designated Class III)

Increment Chart

Two ways to think of increment:

  • first, conceptually
  • second, practically speaking


  • Baseline concentration is the ambient concentration at the baseline date, the date of the first application for a major permit in a PSD area after the major source baseline date has been set.  (....with some exceptions)
  • Increment is additional pollution allowed on top of that

Practically speaking:

  • The exceptions to which emissions “consume” increment make calculating increment more complicated than figuring out what the ambient concentration was on the baseline date and when it exceeds the baseline concentration plus the increment. Increment is a complicated process as the opening and closing of PSD sources cause increment to expand or contract respectively. (See CAA §169(4))
  • Thus, increment is calculated by modeling the change (or D, delta) in ambient concentration inside a PSD area due to “increment consuming emissions”
  • Defining “increment consuming” depends on three dates:
    • Major source baseline date: set by rule after which actual emissions changes at major sources due to construction consume increment
    • Trigger date: set by rule and long past, date after which the minor source baseline date can be triggered
    • Minor source baseline date: the date (after the trigger date) of the first major (i.e. “significant”) NSR permit application in a PSD area, after which ALL actual emissions changes from ALL sources (major, minor, mobile, due to construction or not) consume increment