### 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 2 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 2 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.com 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 2 Boiler 2 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 2 is a top fired boiler with underfired air. The unit is equipped with a dry sorbent injection system (uses 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 #:001.00001.002 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 0 353 228 1 134.2 3 97.5 215.3

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 2 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 2 2010 HAP ICR 6/30/2010

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### Cherokee Unit 2 2010 HAP ICR 6/30/2010 Sampling / Stack Data Results Summary 

### Location Duct - Method 26A Average Run Number 1 2 3 Test Date 4/8/2010 4/8/2010 4/8/2010 Run Start Time 7:25:00 AM 10:39:00 AM 2:23:00 PM
Run Finish Time 10:25:00 AM1:39:00 PM 5:23:00 PM Net Run Time, minutes Dry Gas Meter Volume Sampled, dscf 116.714 114.996 112.725 114.812 Moisture Content of Stack Gas, % 7.91 7.85 7.87 7.877 Moisture Saturation at Stack Gas Temperature, % 100.00 100.00 100.00 100.000 Carbon Dioxide, % 13.2 13.4 13.6 13.400 Oxygen, % 5.3 5.3 4.9 5.167 Average Stack Gas Temperature, °F 273.61 281.56 288.17 281.113 Dry Volumetric Flow Rate, dry scfm 257,579.9 252,508.0 255,461.3 255,183.067 Actual Wet Volumetric Flue Gas Flow Rate, acfm 468,290.8 463,742.6 473,451.3 468,494.900 Percent Isokinetic of Sampling Rate, % F-Factor, dscfm/MMBtu @ %O2 9733 9724 9773 9,743.333 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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### Cherokee Unit 2 2010 HAP ICR 6/30/2010 Emissions Summary

Process Run Data 

### Location: Duct - Method 26A Compound: Hydrogen Chloride Average RunNumber 1 2 3 Mass_mg 0.81 0.741 0.699 0.750 lb/mmBtuO2 2.00E-04 1.85E-04 1.75E-04 0.000 

### Compound: Hydrogen Fluoride Average RunNumber 1 2 3 Mass_mg 2.83 2.72 3.09 2.880 lb/mmBtuO2 6.97E-04 6.79E-04 7.71E-04 0.001



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### Cherokee Unit 2 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 112.64 MW 0 

### 1 Heat Input 1220.5MMBTU/HR 0 1 Main Steam Flow 951.67 % 0 1 Flue Gas Flow Rate 17531 KWSCFH 0 

### 1 DSI Injection Rate 51 % 0 1 Coal Flow 118.89 KPPH 0 1 SO2 Control Setpoint 0.5 LB/MMBTU 0.6 

### 2 Gross Load 112.5 MW 0 2 Heat Input 1233.5MMBTU/HR 0 2 Main Steam Flow 963.11 % 0 

### 2 Flue Gas Flow Rate 17431 KWSCFH 0 2 DSI Injection Rate 51 % 0 2 Coal Flow 119.89 KPPH 0 

### 2 SO2 Control Setpoint 0.5 LB/MMBTU 0.6 3 Gross Load 111.89 MW 0 3 Heat Input 1246.9MMBTU/HR 0 

### 3 Main Steam Flow 958.19 % 0 3 Flue Gas Flow Rate 17637 KWSCFH 0 3 DSI Injection Rate 51 % 0 

### 3 Coal Flow 124.82 KPPH 0 3 SO2 Control 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 OVERFIRE AIR 0 0 1 DRY SORBENT INJECTION 0 0 

### 1 BAGHOUSE 0 0

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### Cherokee Unit 2 2010 HAP ICR 6/30/2010 Sampling / Stack Data Results Detail 

### Location Duct - Method 26A Average Run Number 1 2 3 Test Date 4/8/2010 4/8/2010 4/8/2010 Run Start Time 7:25:00 AM10:39:00 AM 2:23:00 PM Run Finish Time 10:25:00 AM1:39:00 PM 5:23:00 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 0.9888 0.9888 0.9888 0.989 Barometric Pressure, inches of Mercury 24.79 24.79 24.79 24.790 Average Orifice Meter Differential, inches H2O 1.70 1.70 1.70 1.700 Dry Gas Meter Volume Sampled, cubic feet 140.220 142.020 141.440 141.227 Average Dry Gas Meter Temperature, °F 62.31 76.92 85.50 74.910 Dry Gas Meter Volume Sampled, dscf 116.714 114.996 112.725 114.812 Total Moisture Liquid collected, g 212.8 208.3 204.5 208.533 Volume of Water Vapor, standard cubic feet 10.02 9.80 9.63 9.817 Moisture Content of Stack Gas, % 7.91 7.85 7.87 7.877 Moisture Saturation at Stack Gas Temperature, % 100.00 100.00 100.00 100.000 Dry Mole Fraction 0.9209 0.9215 0.9213 0.921 Carbon Dioxide, % 13.2 13.4 13.6 13.400 Oxygen, % 5.3 5.3 4.9 5.167 Carbon Monoxide & Nitrogen, % 81.5 81.3 81.5 81.433 Fuel Factor 1.18 1.16 1.18 Dry Molecular Weight, lb/lb-Mole 30.32 30.36 30.37 30.350 Wet Molecular weight, lb/lb-Mole 29.35 29.39 29.40 29.380 Flue Gas Static Pressure, inches of H2O 0.5 0.5 0.5 0.500 Absolute Flue Gas Pressure, inches of Mercury 24.83 24.83 24.83 24.830 Average Stack Gas Temperature, °F 273.61 281.56 288.17 281.113 Average Velocity Head, inches of H2O 0.5522871177 185710.536485624

0635820.554421693

695514 0.548 Average Stack Gas Velocity, feet/second 53.54 53.02 54.13 53.563 Stack Cross-Sectional Area, square feet 145.776 145.776 145.776 145.776 Dry Volumetric Flow Rate, dry scfm 257,579.9 252,508.0 255,461.3255,183.067 Actual Wet Volumetric Flue Gas Flow Rate, acfm 468,290.8 463,742.6 473,451.3468,494.900 Percent Isokinetic of Sampling Rate, % Percent Excess Air, % 32.7 32.8 29.5 31.667 F-Factor, dscfm/MMBtu @ %O2 9733 9724 9773 9,743.333 Round Duct Diameter, inches 0 0 0 Rectangular Duct Width, inches 97.5 97.5 97.5 Rectangular Duct Length, inches 215.3 215.3 215.3 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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