Printed on: 11/14/2018. Please go to http://policy.umn.edu for the most current version of the Policy or related document.
Appendix

Air Permitting Emission Thresholds

Appendix to Policy

Operating Permit and Permit Amendment Thresholds

Table 1. Air Emission Operating Permit Thresholds (tons/year)

PollutantOption D Registration Permit
(< value)
State Permit
(< value)
Federal Permit
(> value)
Carbon Monoxide (CO) 50 100 100
Nitrogen Oxides (NOx) 50 100 100
Sulfur Dioxide (SO2) 50 100 100
Particulate Matter (PM) 50 100 100
Particulate Matter < 10 microns (PM10) 50 100 100
Volatile Organic Compounds (VOC) 50 100 100
Lead 0.5 10 10
Combined Hazardous Air Pollutants (HAP) 12.5 25 25

Single HAP 5 10 10

Registration permit thresholds are based on actual emissions while other permits are based on "allowable" emissions, which are either potential emissions (8,760 hr/yr) or are calculated considering voluntary operating limits.

Table 2. Air Emission Permit Amendment Thresholds

  Insignificant Minor Moderate/Major
Pollutant lb/hr lb/hr lb/hr
Nitrogen Oxides (NOx) < 2.28 2.28 – 9.13 9.13
Sulfur Dioxide (SO2) < 2.28 2.28 – 9.13 9.13
Volatile Compounds (VOC) < 2.28 2.28 – 9.13 9.13
Particulate Matter <10 microns (PM10) < 0.855 0.855 – 3.42 3.42
Carbon Monoxide (CO) < 2.28 5.70 – 22.80 22.80
Lead < 2.28 0.025 – 0.11 0.11

Table 3 presents examples of the types of individual processes or equipment that may qualify for each amendment type:

Table 3: Air Emission Permit Amendment Thresholds –

Equated to Table 1 by Equipment Type and Approximate Rated Throughput Guidance

  Insignificant Minor Moderate/Major
Process/Equipment Type Throughput Throughput Throughput
New Emergency Generators < 200kw <= 750kw > 750kw
New Peak-Shaving Generators n/a n/a ALL
Boilers – Natural Gas < 10 MMBtu/hr n/a > 10 MMBtu/hr
Boilers – Distillate Oil < 4.4 MMBtu/hr 4.4 – 10 > 10 MMBtu/hr

The preceding tables are provided only for guidance. Please contact DEHS and provide relevant data for final determination.

Construction Permit Thresholds (New Source Review)

The federal New Source Review (NSR) Program ensures that major projects (such as a new steam plant) undergo thorough review before permission to construct is granted. The NSR program affects only those projects that occur at a facility that is already a NSR major source (see column 1 of Table 4), or that, by adding new emission sources, will have potential emissions that exceed column 2 of Table 4. The Twin Cities campus is a NSR source. The other campuses are state-permitted facilities and are likely not going to become subject to the NSR program.

If a project will have a potential emission increase greater than those listed below (for any pollutant), a detailed review must be conducted to ensure that local ambient air quality will not be adversely impacted and that "best available control technology" is installed on new equipment. New Source Review can increase the permitting timeline by one year.

NSR can be avoided by accepting voluntary operating limits (hours or throughput) that would reduce increased annual emissions to less than the thresholds listed below.

Table 4. Air Emission NSR Construction Permit Thresholds (tons/year)

Pollutant Modification of an Existing federal NSR Source Existing State Source or
New Facility
Carbon Monoxide (CO) 100 250
Nitrogen Oxides (NOx) 40 250
Sulfur Dioxide (SO2) 40 250
Particulate Matter (PM) 25 250
Particulate Matter < 10 microns (PM10) 15 250
Volatile Organic Compounds 40 250

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