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Tribal NSR Permitting in Region 8

Region 8 implements the Tribal New Source Review Permit Program for 28 Tribal Nations in Colorado, Montana, North Dakota, South Dakota, Utah, and Wyoming

EPA has authority to issue Nonattainment New Source Review permits (Major Nonattainment NSR) and minor New Source Review permits (minor NSR) on Indian country under 40 CFR part 49. Note that EPA issues Prevention of Significant Deterioration (PSD) permits under 40 CFR 52.21 on Tribal Lands as well. This page focuses on the Tribal Minor NSR Permit Program. Visit EPA's national web page for information on the Major Nonattainment NSR Permit Program and PSD Program in Indian country.

On this page:

About Tribal Minor NSR Permitting

EPA promulgated the Review of New Sources and Modifications in Indian Country on July 1, 2011. The final rule is a federal implementation plan (FIP) that outlines preconstruction permitting of air pollution control requirements for industrial facilities located in Indian Country.

The FIP includes two NSR rules for the protection of air quality in Indian country. One of those rules, known as the Tribal Minor NSR Rule, applies to new industrial facilities or modifications at existing industrial facilities with projected emissions that are more than the minor NSR thresholds but less than the major NSR thresholds, which are generally 100 to 250 tons per year (tpy).

The FIP allows EPA Region 8 to review applications for and issue minor NSR permits to industrial facilities within the federally-recognized external boundaries of 27 Tribal Reservations in the Region (Colorado, Montana, North Dakota, South Dakota, Utah, and Wyoming). The FIP also allows EPA to delegate that authority to tribes in the Region that request it and are able to demonstrate appropriate capability to implement the FIP. Additionally, the FIP can be replaced by an EPA-approved tribal implementation plan (TIP).

The Tribal Minor NSR program provides three options for obtaining permits:
  • Site-Specific Permits: includes case-by-case determinations of the source emission limits as well as any control technology requirements
  • General Permits: permits that have been developed for a number of similar equipment types or facilities to simplify the permit issuance process for facilities; or
  • Synthetic Minor Permits: applies to a facility that has the potential to emit pollutants in amounts that are at or above major source thresholds, but has voluntarily accepted emission limits so that its potential emissions are below those thresholds, allowing the facility to avoid more stringent major NSR requirements of the Clean Air Act, such as PSD, and Title V Operating Permit requirements. This option is available to different types of facilities, including those that emit hazardous air pollutants so that they will not be subject to National Emissions Standards for Hazardous Air Pollutants, also known as Maximum Available Control Technology (MACT) standards, for major sources.

The permit issuance process includes public notice and comment requirements, as well as administrative and judicial review provisions.

Minor NSR Thresholds

Your potential regulated air pollutant emissions must be greater than the thresholds in the table below and less than the major NSR thresholds.

Table 1 to 40 CFR 49.153. Minor NSR Thresholdsa

Regulated NSR pollutant Minor NSR Thresholds for
Non-Attainment Areas (tpy)
Minor NSR Thresholds for
Attainment Areas (tpy)
Carbon monoxide (CO) 5 10
Nitrogen oxides (NOx) 5b 10
Sulfur dioxide (SO2) 5 10
Volatile Organic Compounds (VOC) 2b 5
PM 5 10
PM10 1 5
PM2.5 0.6 3
Lead 0.1 0.1
Fluorides NA 1
Sulfuric acid mist NA 2
Hydrogen sulfide (H2S) NA 2
Total reduced sulfur (including H2S) NA 2
Reduced sulfur compounds (including H2S) NA 2
Municipal waste combustor emissions NA 2
Municipal solid waste landfill emissions
(measured as nonmethane organic compounds)
NA 10
a If part of a tribe's area of Indian country is designated as attainment and another part as nonattainment, the applicable threshold for a proposed facility or modification is determined based on the designation where the facility would be located. If the facility straddles the two areas, the more stringent thresholds apply.

b In extreme ozone nonattainment areas, section 182(e)(2) of the Act specifies that any change at a major facility that results in any increase in emissions is subject to permitting. In other words, any changes to existing major facilities in extreme ozone nonattainment areas must comply with a "0" tpy threshold, but that threshold does not apply to minor facilities.

EPA Contact

Tribal NSR Permits Lead: Claudia Smith (smith.claudia@epa.gov), (303) 312-6520

Applying for Permits - General Instructions

*Electronic Submittals: For electronic submittal of any Tribal NSR permit applications or registration documents, submit documents in PDF format via email to the EPA Contact (smith.claudia@epa.gov), PLUS cc the general Region 8 Air Permitting email (R8AirPermitting@epa.gov), AND the appropriate Tribal Environmental Program (contact the EPA contact (smith.claudia@epa.gov) for appropriate tribal environmental contact emails).*

*Submittals with Confidential Business Information Claims: We discourage the submittal of information claimed to be confidential business information (CBI) if it is not germane to development of the requested permit. However, if you as the applicant deem it necessary, for submittal of any such information claimed to be CBI, you must also submit a claim of confidentiality in accordance with 40 CFR part 2, subpart B. For electronic submittal of any such information claimed to be CBI (per the previous paragraph), please indicate in the subject line of the email, as well as in any body text, that the email contains information subject to a CBI claim.*

Proposed Construction of New Minor Modifications at Existing Major Sources – On or After August 30, 2011

  • Submit Form NEW only for pre-construction approval

New Minor Oil and Natural Gas Industry Sources – Constructed Between August 30, 2011 and October 3, 2016

  • Submit Form REG only within 90 days after you begin operating
  • No permit required

Proposed Construction of New Minor Sources or Minor Modifications at Existing Minor Sources (Except Oil and Natural Gas) – On or After September 2, 2014

  • Submit Form NEW only for pre-construction approval

Proposed Construction of New Minor Sources for Categories with Available General Permits/Permits by Rule – On or After Effective Date of General Permit/Permit by Rule

Proposed Construction of New True Minor Oil and Natural Gas Sources or Minor Modifications at Existing Minor Oil and Natural Gas Sources – On or After October 3, 2016

Any Synthetic Minor Limit Request

  • Submit Form NEW and Form SYNMIN

Tribal Minor NSR Permit Application Modeling Guidance

Dispersion modeling for criteria pollutants and air toxics may be required as part of a Tribal Minor NSR permit application for your facility to ensure protection of the National Ambient Air Quality Standards (NAAQS) in areas of Indian country classified as attainment, attainment/unclassifiable or unclassifiable for the NAAQS. General information on modeling required for permit applications is found on the EPA's websites for Clean Air Act Permit Modeling Guidance. Region 8 is developing guidance for when modeling will be required for proposed new minor sources, minor modifications at an existing minor sources,  synthetic minor sources or modifications, or minor modifications at existing major sources in Indian country. Keep visiting this page for updates on available minor source modeling guidance for Indian country. Until guidance is available, consult guidance available from the state CAA permitting jurisdictions near the area of Indian country your proposed project will be located and schedule a pre-application meeting with Region 8 for project-specific modeling guidance.

Region 8 Site-Specific Application Forms

Existing Source Registration Form (REG)
New Source General Application Form (NEW)
Synthetic Minor Limit Request Form (SYNMIN)
Facility Closure Form (CLOSURE)
Change in Ownership Form (OWN)
Permit Amendment Application Form (AMEND)
Facility Location Change Form (LOC)
Facility Contact Information Change Form (INFO)

Delegated Permitting Authorities

If your source is located within the exterior boundaries of any of the following Reservations authority for Minor NSR permitting has been delegated to the associated governing Tribes and you should work with that Tribe in order to comply with applicable permitting requirements. Each listed Reservation/Tribe contains a link to contact information for the delegated Tribe's permitting program.

  • None at this time

Approved Tribal Implementation Plans

If your source is located within the exterior boundaries of any of the following Reservations full authority for Minor NSR permitting has been approved by EPA for the associated governing Tribes and you should work with that Tribe in order to comply with applicable permitting requirements. Each listed Reservation/Tribe contains a link to contact information for the approved Tribe's permitting program.

  • None at this time