### Name: Ms. Misty Hanson

Title: Environmental Compliance Specialist Company: Minnesota Power Sign Date: Name: Mr. James Tryba Title: North Service Manager Company: GE International, Inc. Sign Date: 5/3/2010 Permitted Facility Representative / Date Testing Company Representative / Date 

## Boswell Energy Center Final Test Report for

/ / Based on information and belief formed after reasonable inquiry, I certify that the statements and information in this test report are true, accurate, and complete. I have reviewed all testing details and results in this test report and hereby certify that the test report is authentic and accurate.

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### Boswell Energy Center

Facility Information: Minnesota Power Clay Boswell Energy 1210 NW 3rd Street

Cohasset MN55721 Contact:Misty Hanson Phone:218-313-5446 Fax: 218-3313-4695 Email: mhanson@mnpower.com Testing Company: GE International, Inc. 1301 Corporate Center Drive Suite 177 Eagan MN55121 Contact:James Tryba Phone:651-686-0700 Fax: 651-686-4434 Email:james.tryba@ge.com

Air Permit Number: 1893 Permitted Source ID/Name: 3 3 Permitted Maximum Process Rate: 3355 mmBtu per hour max design capaMax. Normal Operation Process Rate: 4115 mmBtu per hour Target Process Test Rate 4115 mmBtu per hour

Description of the source (including control equipment). Please see the attachments for source or process flow diagram: Boswell Energy Center Unit 3 is a 385GMW coal fired electric utility steam generating boiler. The main fuel is sub bituminous coal. The unit is permitted to also burn natural gas through igniters, propane, distillate oil, limited amounts of boiler cleaning agents, used oil, oily coal, oily paper based floor dry, wastewater treatment plant sludge, and oily materials.

The following describes any modifications and/or deviations to the applicable test methods. If alternative methods were requested, see the attachments for documentation of request AND approval, including dates. Industry/SCC/NAIS22

Sampling Location Information:

Test Parameter Information: AFS #:2706100004 FRS #:110037369638

SCC / Description10100226 External Combustion Boilers - Electric Generation - Bituminous/Subbituminous Coal - Pulverized Coal: Dry Bottom Tangential (Subbituminous Coal)
The following state and federal regulations that apply to the proposed testing:

Location Round

Duct Diam. Distance from upstream dist. Distance from

downstream dist. Number of

Traverse Ports Equiv. Diam Min.Travers Points Rect. Duct Length /Width Unit 3 0 360 168 8 348 24 180 300

Target Parameter Test Method Number of

Test Runs Test Run

Duration Sample

Points Comments Location Hydrogen Chloride Method 26A 3 180 0 Unit 3 Hydrogen Fluoride Method 26A 3 180 0 Unit 3 Regulation Description Compound Limit Unit None 0



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### Boswell Energy Center

The following describes any modifications and/or deviations to the applicable test methods. If alternative methods were requested, see the attachments for documentation of request AND approval, including dates. The hydrogen cyanide (HCN) testing was accidentally overlooked and therefore not performed during this information collection test program. The attached file is email coorespondance regarding the issue, and excusing the HCN data requirement for this site.



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### Boswell Energy Center

Sampling / Stack Data Results Summary 

### Location Unit 3 - Method 26A Average Run Number 1 2 3 Test Date 3/31/2010 3/31/2010 3/31/2010 Run Start Time 6:11:00 AM 10:40:00 AM 2:40:00 PM

Run Finish Time 9:54:30 AM2:10:30 PM 5:59:30 PM Net Run Time, minutes 180 180 180 Dry Gas Meter Volume Sampled, dscf 92.106 93.574 91.154 92.278 Moisture Content of Stack Gas, % 15.11 15.91 15.72 15.580 Moisture Saturation at Stack Gas Temperature, % 15.45 15.53 15.52 15.500 Carbon Dioxide, % 13.5 13.4 13.5 13.467 Oxygen, % 6.2 6.3 6.2 6.233 Average Stack Gas Temperature, °F 128.00 128.38 128.46 128.280 Dry Volumetric Flow Rate, dry scfm 919,243.7 935,378.5 910,513.5 921,711.900 Actual Wet Volumetric Flue Gas Flow Rate, acfm 1,301,625.01,325,700.0 1,286,325.01,304,550.00 0 Percent Isokinetic of Sampling Rate, % 97.6 97.5 97.5 97.533 F-Factor, dscfm/MMBtu @ %O2 9820 9820 9820 9,820.000 Fw 0 0 0 0.000 Fc 1840 1840 1840 1,840.000



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### Boswell Energy Center

Emissions Summary

Process Run Data 

### Location: Unit 3 - Method 26A Compound: Filterable Particulate Average RunNumber 1 Mass_mg 0 0.000 lb/mmBtuO2 0.00E+00 0.000 

### Compound: Hydrogen Chloride Average RunNumber 1 2 3 Mass_mg 1.6 1.5 1.5 1.533 lb/mmBtuO2 5.35E-04 4.97E-04 5.07E-04 0.001 

### Compound: Hydrogen Fluoride Average RunNumber 1 2 3 Mass_mg 340 0.31 0.32 113.543 lb/mmBtuO2 1.14E-01 1.03E-04 1.08E-04 0.038



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### Boswell Energy Center

Process Run Data

APCD Run Data

Process Lab Run Data 

### Run Name Value UOM Comments Target Value 1 Heat Input 3716Million Btus/hr 

### 2 Heat Input 3706Million Btus/hr 3 Heat Input 3734Million Btus/hr 1 Gross Megawatts 381 MW 0 

### 2 Gross Megawatts 380 MW 0 3 Gross Megawatts 381 MW 0 1 Steam 2052 1000 lb/hr 0 

### 2 Steam 2043 1000 lb/hr 0 3 Steam 2037 1000 lb/hr 0 1 Limestone slurry feed 19571 lb/hr 0 

### 2 Limestone slurry feed 20453 lb/hr 0 3 Limestone slurry feed 20272 lb/hr 0

Run Name Value UOM Comments Target Value 

### 1 LOW NOX BURNERS 0 0 1 OVERFIRE AIR 0 0 1 SCR (SELECTIVE CATALYTIC REDUCTION) 0 0 

### 1 WET SCRUBBER 0 0 1 BAGHOUSE 0 0

Run Name Value UOM Comments 1 None 0



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### Boswell Energy Center

Sampling / Stack Data Results Detail 

### Location Unit 3 - Method 26A Average Run Number 1 2 3 Test Date 3/31/2010 3/31/2010 3/31/2010 Run Start Time 6:11:00 AM10:40:00 AM 2:40:00 PM Run Finish Time 9:54:30 AM 2:10:30 PM 5:59:30 PM Net Traversing Points 24 24 24 Net Run Time, minutes 180 180 180 Nozzle Diameter, inches 0.198 0.198 0.198 0.198 Pitot Tube Coefficient 0.84 0.84 0.84 0.840 Dry Gas Meter Calibration Factor 1.007 1.007 1.007 1.007 Barometric Pressure, inches of Mercury 27.75 27.87 27.96 27.860 Average Orifice Meter Differential, inches H2O 0.98 1.02 0.97 0.990 Dry Gas Meter Volume Sampled, cubic feet 102.942 103.797 100.984 102.574 Average Dry Gas Meter Temperature, °F 92.58 90.85 91.85 91.760 Dry Gas Meter Volume Sampled, dscf 92.106 93.574 91.154 92.278 Total Moisture Liquid collected, g 348.3 376 361.1 361.800 Volume of Water Vapor, standard cubic feet 16.39 17.70 17.00 17.030 Moisture Content of Stack Gas, % 15.11 15.91 15.72 15.580 Moisture Saturation at Stack Gas Temperature, % 15.45 15.53 15.52 15.500 Dry Mole Fraction 0.8489 0.8447 0.8448 0.846 Carbon Dioxide, % 13.5 13.4 13.5 13.467 Oxygen, % 6.2 6.3 6.2 6.233 Carbon Monoxide & Nitrogen, % 80.3 80.3 80.3 80.300 Fuel Factor 1.09 1.09 1.09 Dry Molecular Weight, lb/lb-Mole 30.41 30.40 30.41 30.407 Wet Molecular weight, lb/lb-Mole 28.53 28.54 28.52 28.530 Flue Gas Static Pressure, inches of H2O -0.4 -0.25 -0.3 -0.317 Absolute Flue Gas Pressure, inches of Mercury 27.72 27.85 27.94 27.837 Average Stack Gas Temperature, °F 128.00 128.38 128.46 128.280 Average Velocity Head, inches of H2O 0.8727033636 756990.909400115

8809090.858314128

444905 0.880 Average Stack Gas Velocity, feet/second 57.85 58.92 57.17 57.980 Stack Cross-Sectional Area, square feet 375.000 375.000 375.000 375.000 Dry Volumetric Flow Rate, dry scfm 919,243.7 935,378.5 910,513.5921,711.900 Actual Wet Volumetric Flue Gas Flow Rate, acfm 1,301,625.0 1,325,700.0 1,286,325.01,304,550.0 00 Percent Isokinetic of Sampling Rate, % 97.6 97.5 97.5 97.533 Percent Excess Air, % 41.3 42.3 41.3 41.633 F-Factor, dscfm/MMBtu @ %O2 9820 9820 9820 9,820.000 Round Duct Diameter, inches 0 0 0 Rectangular Duct Width, inches 180 180 180 Rectangular Duct Length, inches 300 300 300 Fw 0 0 0 0.000 Fc 1840 1840 1840 1,840.000



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