1. Fuels For Schools General Air Quality Considerations Diane R. Lorenzen, P.E. Montana Department of Environmental Quality October 17, 2007

3. Air Quality Topics Emissions EstimatesEmissions Estimates –Criteria Air Pollutants –Hazardous Air Pollutants (HAPS) Is an Air Quality Permit Required?Is an Air Quality Permit Required? Ambient Air ImpactsAmbient Air Impacts Non-attainment AreasNon-attainment Areas

4. Criteria Air Pollutants Criteria Air Pollutants Regulated by Air Quality Standards Carbon Monoxide (CO)Carbon Monoxide (CO) Nitrogen Dioxide (NO 2 )Nitrogen Dioxide (NO 2 ) Sulfur Dioxide (SO 2 )Sulfur Dioxide (SO 2 ) Particulate Matter < 10 µm (PM 10 )Particulate Matter < 10 µm (PM 10 ) Particulate Matter < 2.5 µm (PM 2.5 )Particulate Matter < 2.5 µm (PM 2.5 ) Ozone, regulated as Volatile Organic Compounds (VOC)Ozone, regulated as Volatile Organic Compounds (VOC) Lead (Pb) [also a HAP]Lead (Pb) [also a HAP]

5. 5 Criteria Pollutant Emissions Comparison Criteria Pollutant Emissions Comparison Potential to Emit (PTE) Tons of pollutant per year (tpy) 19 MMBtu/hr boiler (heat input) Pollu- tant WoodFuelDistillate Fuel Oil LP Gas (Propane) Natural Gas Fuel CoalFuel PM 10 16.61.040.360.6358 PM 2.5 130.80.30.631 NOx18.311.012.82.6642 SO 2 2.084.35<0.010.05 110 (unc) CO11.73.072.927.0048 VOC1.410.440.460.465.7 Fuel 2 tons/hr 140 gal/hr 208 gal/hr 19,000 scf/hr 1 ton/hr

6. Example HAP Emissions Example HAP Emissions 2 MMBtu/hr Wood-fired Boiler HAP Emission Factor (lb/MMBtu) (1) Emission Rate (lb/hr) Emission Rate (tpy) Hydrogen Chloride* 1.9E-020.0380.17 Formaldehyde4.4E-030.0090.038 Benzene4.2E-030.0080.037 Acrolein4.0E-030.0080.035 Manganese1.6E-030.0030.014 Arsenic2.2E-054.4E-050.0002 (1) Emission Factors from AP-42, Section 1.6, External Wood Combustion

7. PM 10 Emissions Comparison Wood Burner Burner Size Heat Input PM 10 Emission Factor (lb/MMBtu) PM 10 Emissions (tpy) Small Wood Stove 18,000 Btu/hr 0.530.04 Pellet Furnace 85,000 Btu/hr 0.320.12 Outdoor Furnace 500,000 Btu/hr 0.61.31 Typical FFS Boiler 2 MMBtu/hr 0.302.63 Large FFS Boiler 19 MMBtu/hr 0.2016.6 Small Sawmill Boiler 32 MMBtu/hr 0.3042.0 Large Hog Fuel Boiler 292 MMBtu/hr 0.02430.7

8. Boiler Stack and Buildings

9. Building Downwash

10. Ambient Air Quality Boundary Industrial Facility School Yard

11. Stack Height Considerations Minimize building downwash effectMinimize building downwash effect Good Engineering Practice Stack Height (GEP)Good Engineering Practice Stack Height (GEP) > 2.5 times adjacent building height

12. Sample Boiler Modeling Results

13. Non-Attainment Areas Wood Smoke is a primary contributor to PM2.5 impacts in Montana’s mountain valleys.

15. Locating a Project in a Non-attainment Area Contact state and local regulatory authorities at the beginning of planning Consider the effects of NAA restrictions on boiler operation and project economics

17. Source: http://www.fuelsforschools.org

18. Open Burning vs. Fuel Boiler

19. Carbon Dioxide Source: http://www.fuelsforschools.org

20. Burning Seasons in Montana Heating Season Open Burning Prohibited General Open Burning Fall Regulated Burning Fire Season JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC

21. Montana DEQ Air Quality Contacts Air permitting, emissions estimation and stack height: Deb Skibicki (406) 444-1472 Non-attainment Area information: Bob Habeck (406) 444-7305