Permit applications must include detailed emissions calculations on form GI-07 (Facility emissions summary) or CAP-GI-07 (Capped permit facility emissions summary). The calculations help determine which permit type or permit amendment is needed. The information must be provided in the permit application, and in an editable spreadsheet that includes all formulas/equations in the calculated cells.
Calculating potential emissions
Methods for calculating a facility's potential to emit include:
- Using emission factors as defined in Minn. R. 7005.0100, subp. 10a. This rule includes emission factors found in the U.S. EPA's Compilation of Air Emission Factors or its Factor Information Retrieval (FIRE) Data System, as well as other possible sources.
- Material balance methods.
- Direct measurement of emissions.
Applicants must use whichever calculation method is most representative and accurate. If using emissions factors, you must use the most recent emission factor available for each pollutant. If you use vendor certification or stack test data to limit your potential-to-emit, the factor you used will be used to establish permit limits and you may be required to do ongoing testing to confirm that the information is representative of your operations.
Describe any bottlenecks or physical limitations in your process(es) that restrict your potential-to-emit. Describe any permit limits you will propose (fuel type or usage, hours of operation, material throughput, etc.) that would restrict your potential to emit:
Calculating actual emissions
Minnesota rules specify the preferred methods for calculating a facility’s actual emissions:
- continuous emission monitor data
- performance test data
- volatile organic compounds material balance, sulfur dioxide material balance, emission factor, or enforceable limits
- facility proposal
Emissions spreadsheet requirements
We recommend you use the MPCA emission calculation forms for the following processes:
For these processes, unless you are applying for a Registration Option D permit, you must use the MPCA-provided form or create your own that includes all of the same types of information in the same general format.
The MPCA also has calculation templates for storage tanks. For these processes, we recommend that you use the MPCA provided template, but, if needed, you can create your own spreadsheet that includes all of the information noted on the storage tanks webpage.
If no calculation form for your emissions unit(s) is available on the forms page or template available on one of the pages linked on the left, create an editable spreadsheet with the applicable information indicated above and on the pages at left. Each step in your calculation spreadsheets needs to be clear and easy to follow.
Facility information
- Air quality facility ID number, the first eight digits of the permit.
- Agency interest ID number assigned to your facility through the Tempo database.
- Facility name
- Emissions units, including fugitive sources, storage tanks, etc. Include the Tempo subject item ID number for each unit and a description of the unit.
- Stack/vent designation numbers, in Form GI-04 or similar form, except when applying for registration permit Option D
- Pollution control equipment, including each unit's identification or designation number and a description of the equipment. If none, indicate no control equipment. If you are applying for a registration permit Option D, just provide a description of the control equipment.
- Batch or continuous process type, as applicable
- Maximum capacity, or the maximum number of units that can be processed per hour and the units used. If needed, attach additional sheets to describe the process and any rate limiting steps.
- For grain elevators and feed mills: Calculate maximum capacity by multiplying the highest grain throughput of the previous five operating years by 1.2. For terminal grain elevators or feed mills, indicate the capacity of each emission unit.
- Source of emission factors. Provide your source for each emission factor
- Operating limitations, or the permit limits you propose to restrict your potential-to-emit – see Synthetic minor permit limits. Attach additional spreadsheets or other information, if needed. Cite any rules that apply.
- Additional emissions calculations on a separate worksheet. This is for emissions units described by the calculations that include other types of emissions. For example, an emissions process or unit that also burns fuel, uses solvents, or emits greenhouse gases will need a separate worksheet for those secondary emissions.
- Relevant process parameters needed for calculating emissions, such as fuel parameters for each type of fuel used, maximum pollutant content of input materials, firing method for external combustion sources, etc.
Plating processes
In addition to the item above, provide:
- Type of plating, such decorative chrome, hard chrome, chromic acid, or other.
- Operating parameters: Note the capacity in total amps for an electroplating operation, or the capacity in total square foot per hour capacity for an anodizing operation.
- List the pollution-emitting solutions or chemicals used in the plating process.
List the pollutants your facility emits in the left column, and each step of your calculation will be another column in your spreadsheet. Provide the formula or equation for each calculation. Add columns for additional calculations or information specific to your operation. See the Greenhouse gas emissions calculations page for calculation instructions for GHG-emitting units. Your spreadsheet must include a tab compiling the emissions for each source and the emission totals at the facility. The GI-07 Facility emissions summary spreadsheet can be copied into a tab in your spreadsheet for this purpose. If you do not use the GI-07 spreadsheet form, your spreadsheet must include an equivalent tab that includes the same information using the same format as the GI-07 form. The emissions summary tab needs to link the pollutant emissions data from the emission calculation tabs. The pollutant totals for your facility need to be summed from the emissions for the separate sources. Do not hard enter emissions data into the emissions summary tab.
- List the pollutants that the process or unit emits:
- particulate matter (PM)
- PM smaller than 10 microns (PM10)
- PM smaller than 2.5 microns (PM2.5)
- lead
- sulfur dioxide
- nitrogen oxides
- volatile organic compounds
- carbon monoxide
- hazardous air pollutants (HAPs), listed individually
- total emissions of HAPs
- greenhouse gases, listed individually. Provide the carbon dioxide equivalent amount.
- fluorides
- sulfuric acid mist
- hydrogen sulfide
- total reduced sulfur (includes hydrogen sulfide)
- Reduced sulfur compounds (includes hydrogen sulfide)
- municipal waste combustor (MWC) organics
- MWC metals
- MWC acid gases
- municipal solid waste landfill gases
- For each pollutant, provide the emission factor in pounds per unit of production, or per unit of material usage obtained from the sources listed above and list the source for each factor. Show any calculations used to determine maximum continuous rates. Attach a separate sheet, if necessary.
- Calculate the emission rate by multiplying the emission factor by the maximum capacity of the operation (in units of production per hour, material usage per hour, or the units the emission factor is in).
- For plating processes using emissions factors in pounds per amp-hour: Emission rate (lb/hr) = Emission factor (lb/amp-hr) x Electroplating capacity (amps).
- For plating processes using emissions factors in pounds per square foot-hour: Emission rate (lb/hr) = Emission factor (lb/hr-ft2) x Anodizing capacity (ft2)
- Calculate the maximum uncontrolled emissions (tons/year): Emission rate (lb/hr) x 8760 (hr/yr) x [1 ton ÷ 2000 lb]
- Skip this step if you are applying for a registration Option D permit.
- Include the pollution control efficiency percentage, which is the capture efficiency percentage multiplied by the destruction/collection efficiency percentage (shown on Form GI-05A or similar), for each pollutant. Form CD-05 also requires a plan to demonstrate and maintain the destruction/collection efficiency. If there is no control for a particular pollutant, indicate “zero” as the control efficiency.
- Find the maximum controlled emissions rate (lb/hr): Emission rate (lb/hr) x {[100 - Pollution control efficiency] ÷100}
- Calculate the maximum controlled emissions (tons/year): Max. uncontrolled emissions [tons/year] x {[100 - Pollution control efficiency] ÷100}
- Include the maximum hourly emission rate allowed under 40 CFR pt. 60, 40 CFR pt. 61, 40 CFR pt. 63, or Minn. R. ch. 7011. See form GI-09 for applicable regulations.
- Find the limited controlled emissions (tons/year) by repeating the emission rate calculation (multiplying the emission factor by the maximum capacity of the operation) but take into account all your facility's operating limits, such as hours of operation, amount of material handled, etc. If an emission unit is subject to an emission limitation specified in 40 CFR pt. 60, 40 CFR pt. 61, 40 CFR pt. 63, or Minn. R. ch. 7011 or you are proposing a more stringent limit, you must indicate this and include those factors in the calculation. Skip this step if you are seeking a registration Option D permit.
- Calculate the actual uncontrolled emissions rates by multiplying the actual production rate or material usage rate (whichever corresponds to the emissions factor) by the emissions factor. For registration permit Option D applicants, use the previous 12 months of operation data. For other permittees, for existing emission units, take an average of the usage data from the previous two calendar years and for new units, estimate the hours of operation or material use.
- Calculate actual uncontrolled emissions (tons/year): Emission factor (lb/unit) x actual production (units/year) x [1 ton/2000 lb]
- Calculate actual controlled emissions (tons/year): Actual uncontrolled emissions [ton/year] x [100 - Pollution control efficiency]