### Name: Steve Mills

Title: Designated Representative Company: Public Service Company of Colorado Sign Date: 6/30/2010 Name: Patrick Clark Title: Owner Company:Airtech Environmental Services Sign Date: 6/30/2010 Permitted Facility Representative / Date Testing Company Representative / Date 

## Cherokee Unit 1 2010 HAP ICR

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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### Cherokee Unit 1 2010 HAP ICR 6/30/2010 Facility Information: Cherokee 6198 Franklin Street

Denver CO80216 Contact:Chad Campbell Phone: 303-294-2111 Fax: 303-294-2859 Email: chad.campbell@xcelenergy Testing Company: Airtech Environmental Services, Inc. 5776 Lamar Street

Arvada CO80002 Contact:Patrick Clark Phone:303-670-0530 Fax: 303-670-4130 Email: pclark@airtechenv.com

Air Permit Number: 96OPAD130 Permitted Source ID/Name: Unit 1 Boiler 1 Permitted Maximum Process Rate:Max. Normal Operation Process Rate: Target Process Test Rate

Description of the source (including control equipment). Please see the attachments for source or process flow diagram: Cherokee Station Unit 1 is a top fired boiler with low Nox burners and underfired air. The unit is equipped with dry sorbent injection (DSI - Trona) to control SO2 emissions and an FFDC to control PM emissions. The unit typically fires Colorado bituminous coal.

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. Per discussion with Peter Westlin on January 22, 2010, a three point traverse was approved since there are no Industry/SCC/NAIS221112

Sampling Location Information:

Test Parameter Information: AFS #:001.00001.001 FRS #:

SCC / Description10100202 External Combustion Boilers - Electric Generation - Bituminous/Subbituminous Coal - Pulverized Coal: Dry Bottom (Bituminous 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 Duct 0 304.5 48.62 1 127.96 3 84.756 261

Target Parameter Test Method Number of

Test Runs Test Run

Duration Sample

Points Comments Location Hydrogen Fluoride Method 26A 3 180 0 Duct Hydrogen Chloride Method 26A 3 180 0 Duct



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### Cherokee Unit 1 2010 HAP ICR 6/30/2010 entrained water droplets in the flue gas. Sampling was conducted at a constant rate of 0.75 cfm and utilized the Method 26 impingers.



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### Cherokee Unit 1 2010 HAP ICR 6/30/2010

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### Cherokee Unit 1 2010 HAP ICR 6/30/2010 Sampling / Stack Data Results Summary 

### Location Duct - Method 26A Average Run Number 2 3 4 Test Date 4/6/2010 4/6/2010 4/7/2010 Run Start Time 8:34:00 AM 11:53:00 AM 9:40:00 AM
Run Finish Time 11:34:00 AM2:53:00 PM12:40:00 PM Net Run Time, minutes Dry Gas Meter Volume Sampled, dscf 120.417 117.753 118.399 118.856 Moisture Content of Stack Gas, % 7.95 8.83 12.05 9.610 Moisture Saturation at Stack Gas Temperature, % 100.00 100.00 100.00 100.000 Carbon Dioxide, % 12.6 12.9 13.3 12.933 Oxygen, % 6.35 6.25 5.75 6.117 Average Stack Gas Temperature, °F 328.44 331.67 332.72 330.943 Dry Volumetric Flow Rate, dry scfm 263,928.5 263,583.9 252,619.9 260,044.100 Actual Wet Volumetric Flue Gas Flow Rate, acfm 525,011.7 531,555.9 527,500.4 528,022.667 Percent Isokinetic of Sampling Rate, % F-Factor, dscfm/MMBtu @ %O2 9859 9697 9710 9,755.333 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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### Cherokee Unit 1 2010 HAP ICR 6/30/2010 Emissions Summary

Process Run Data 

### Location: Duct - Method 26A Compound: Hydrogen Chloride Average RunNumber 2 3 4 Mass_mg 1.04 0.615 0.991 0.882 lb/mmBtuO2 2.70E-04 1.59E-04 2.47E-04 0.000 

### Compound: Hydrogen Fluoride Average RunNumber 2 3 4 Mass_mg 2.64 2.48 2.37 2.497 lb/mmBtuO2 6.84E-04 6.42E-04 5.91E-04 0.001



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### Cherokee Unit 1 2010 HAP ICR 6/30/2010 Process Run Data

APCD Run Data

Process Lab Run Data 

### Run Name Value UOM Comments Target Value 1 Gross Load 98.94 MW 0 

### 1 Heat Input 1173.1MMBTU/HR 0 1 Main Steam Flow 848.84 KPPH 0 1 Flue Gas Flow Rate 17385 KWSCFH 0 

### 1 DSI Injection Rate 29.95 % 0 1 Coal Flow 110.15 KPPH 0 1 SDA SO2 Setpoint 0.5 LB/MMBTU 0.6 

### 2 Gross Load 98.04 MW 0 2 Heat Input 1180.8MMBTU/HR 0 2 Main Steam Flow 833.73 KPPH 0 

### 2 Flue Gas Flow Rate 17642 KWSCFH 0 2 DSI Injection Rate 35 % 0 2 Coal Flow 110.83 KPPH 0 

### 2 SDA SO2 Setpoint 0.5 LB/MMBTU 0.6 3 Gross Load 99.57 MW 0 3 Heat Input 1201.4MMBTU/HR 0 

### 3 Main Steam Flow 867.36 KPPH 0 3 Flue Gas Flow Rate 17568 KWSCFH 0 3 DSI Injection Rate 30 % 0 

### 3 Coal Flow 107.11 KPPH 0 3 SDA SO2 Setpoint 0.5 LB/MMBTU 0.6 1 Heat Input 0 Million Btus/million BTU using CO2 0

Run Name Value UOM Comments Target Value 

### 1 LOW NOX BURNERS 0 0 1 OVERFIRE AIR 0 0 

### 1 DRY SORBENT INJECTION 0 0 1 BAGHOUSE 0 0



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### Cherokee Unit 1 2010 HAP ICR 6/30/2010 Sampling / Stack Data Results Detail 

### Location Duct - Method 26A Average Run Number 2 3 4 Test Date 4/6/2010 4/6/2010 4/7/2010 Run Start Time 8:34:00 AM11:53:00 AM 9:40:00 AM Run Finish Time 11:34:00 AM2:53:00 PM12:40:00 PM Net Traversing Points 18 18 18 Net Run Time, minutes Nozzle Diameter, inches Pitot Tube Coefficient 0.84 0.84 0.84 0.840 Dry Gas Meter Calibration Factor 1.0018 1.0018 0.9888 0.997 Barometric Pressure, inches of Mercury 24.38 24.38 24.44 24.400 Average Orifice Meter Differential, inches H2O 1.80 1.80 1.70 1.767 Dry Gas Meter Volume Sampled, cubic feet 145.220 143.230 143.870 144.107 Average Dry Gas Meter Temperature, °F 62.61 67.11 60.86 63.527 Dry Gas Meter Volume Sampled, dscf 120.417 117.753 118.399 118.856 Total Moisture Liquid collected, g 220.9 242.3 344.6 269.267 Volume of Water Vapor, standard cubic feet 10.40 11.41 16.22 12.677 Moisture Content of Stack Gas, % 7.95 8.83 12.05 9.610 Moisture Saturation at Stack Gas Temperature, % 100.00 100.00 100.00 100.000 Dry Mole Fraction 0.9205 0.9117 0.8795 0.904 Carbon Dioxide, % 12.6 12.9 13.3 12.933 Oxygen, % 6.35 6.25 5.75 6.117 Carbon Monoxide & Nitrogen, % 81.05 80.85 80.95 80.950 Fuel Factor 1.15 1.14 1.14 Dry Molecular Weight, lb/lb-Mole 30.27 30.31 30.36 30.313 Wet Molecular weight, lb/lb-Mole 29.29 29.22 28.87 29.127 Flue Gas Static Pressure, inches of H2O 0.3 0.3 0.3 0.300 Absolute Flue Gas Pressure, inches of Mercury 24.40 24.40 24.46 24.420 Average Stack Gas Temperature, °F 328.44 331.67 332.72 330.943 Average Velocity Head, inches of H2O 0.5703454148 608790.580714648

1361910.565825961

879388 0.572 Average Stack Gas Velocity, feet/second 56.96 57.67 57.23 57.287 Stack Cross-Sectional Area, square feet 153.620 153.620 153.620 153.620 Dry Volumetric Flow Rate, dry scfm 263,928.5 263,583.9 252,619.9260,044.100 Actual Wet Volumetric Flue Gas Flow Rate, acfm 525,011.7 531,555.9 527,500.4528,022.667 Percent Isokinetic of Sampling Rate, % Percent Excess Air, % 42.2 41.4 36.8 40.133 F-Factor, dscfm/MMBtu @ %O2 9859 9697 9710 9,755.333 Round Duct Diameter, inches 0 0 0 Rectangular Duct Width, inches 84.756 84.756 84.756 Rectangular Duct Length, inches 261 261 261 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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