### Name: Steve Mills

Title: Designated Representative Company: Public Service Company of Colorado Sign Date: 6/25/2010 Name: Patrick Clark Title: Owner Company:Airtech Environmental Services Sign Date: 6/25/2010 Permitted Facility Representative / Date Testing Company Representative / Date 

## Cherkee Unit 4 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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### Cherkee Unit 4 2010 HAP ICR 6/25/2010 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 4 Boiler 4 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 4 is a 350 MW tangentially fired CE boiler with low Nox burners and overfired air. The unit is equipped with a spray dryer absorber (SDA) 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 #:001.0001.004 FRS #:

SCC / Description10100212 External Combustion Boilers - Electric Generation - Bituminous/Subbituminous Coal - Pulverized Coal: Dry Bottom (Tangential) (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 0 180.32 240.42 1 261.33 3 196 392

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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### Cherkee Unit 4 2010 HAP ICR 6/25/2010 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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### Cherkee Unit 4 2010 HAP ICR 6/25/2010

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### Cherkee Unit 4 2010 HAP ICR 6/25/2010 Sampling / Stack Data Results Summary 

### Location Duct - Method 26A Average Run Number 1 2 3 Test Date 3/23/2010 3/23/2010 3/24/2010 Run Start Time 7:17:00 AM 10:38:00 AM 7:14:00 AM
Run Finish Time 10:17:00 AM1:38:00 PM10:14:00 AM Net Run Time, minutes Dry Gas Meter Volume Sampled, dscf 119.887 118.125 121.231 119.748 Moisture Content of Stack Gas, % 11.64 11.91 11.21 11.587 Moisture Saturation at Stack Gas Temperature, % 43.31 42.64 39.42 41.790 Carbon Dioxide, % 13.1 13.2 13.1 13.133 Oxygen, % 5.7 5.5 5.9 5.700 Average Stack Gas Temperature, °F 164.39 163.67 160.78 162.947 Dry Volumetric Flow Rate, dry scfm 910,807.2 908,360.1 894,178.6 904,448.633 Actual Wet Volumetric Flue Gas Flow Rate, acfm 1,478,377.01,479,017.2 1,423,314.01,460,236.06 7 Percent Isokinetic of Sampling Rate, % F-Factor, dscfm/MMBtu @ %O2 9633 9604 9638 9,625.000 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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### Cherkee Unit 4 2010 HAP ICR 6/25/2010 Emissions Summary

Process Run Data 

### Location: Duct - Method 26A Compound: Hydrogen Chloride Average RunNumber 1 2 3 Mass_mg 1.31 0.798 0.808 0.972 lb/mmBtuO2 3.19E-04 1.94E-04 1.97E-04 0.000 

### Compound: Hydrogen Fluoride Average RunNumber 1 2 3 Mass_mg 0.542 0.512 0.542 0.532 lb/mmBtuO2 1.32E-04 1.25E-04 1.32E-04 0.000



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### Cherkee Unit 4 2010 HAP ICR 6/25/2010 Process Run Data

APCD Run Data

Process Lab Run Data 

### Run Name Value UOM Comments Target Value 1 Gross Load 333.73 MW 0 

### 1 Heat Input 3111.9MMBTU/HR 0 1 Main Steam Flow 1918.7 KPPH 0 1 Flue Gas Flow Rate 45739 KWSCFH 0 

### 1 SDA Total Slurry Flow 226.13 GPM 0 1 SDA Pressure Drop 2.36 in H2O 0 1 Coal Flow 282.92 KPPH 0 

### 1 SDA SO2 Setpoint 0.11 LB/MMBTU 0.12 2 Gross Load 332.48 MW 0 2 Heat Input 3062.0MMBTU/HR 0 

### 2 Main Steam Flow 1916.9 KPPH 0 2 Flue Gas Flow Rate 44701 KWSCFH 0 2 SDA Total Slurry Flow 239.74 GPM 0 

### 2 SDA Pressure Drop 2 in H2O 0 2 Coal Flow 282.96 KPPH 0 2 SDA SO2 Setpoint 0.11 LB/MMBTU 0.12 

### 3 Gross Load 330.29 MW 0 3 Heat Input 2956.7MMBTU/HR 0 3 Main Steam Flow 1913.4 KPPH 0 

### 3 Flue Gas Flow Rate 43329 KWSCFH 0 3 SDA Total Slurry Flow 202.75 GPM 0 3 SDA Pressure Drop 1.82 in H2O 0 

### 3 Coal Flow 282.08 KPPH 0 3 SDA SO2 Setpoint 0.11 LB/MMBTU 0.12 

### 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 SCRUBBER 0 0 1 BAGHOUSE 0 0



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### Cherkee Unit 4 2010 HAP ICR 6/25/2010

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### Cherkee Unit 4 2010 HAP ICR 6/25/2010 Sampling / Stack Data Results Detail 

### Location Duct - Method 26A Average Run Number 1 2 3 Test Date 3/23/2010 3/23/2010 3/24/2010 Run Start Time 7:17:00 AM10:38:00 AM 7:14:00 AM Run Finish Time 10:17:00 AM 1:38:00 PM10:14:00 AM 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 1.0018 1.002 Barometric Pressure, inches of Mercury 24.7 24.68 24.93 24.770 Average Orifice Meter Differential, inches H2O 1.80 1.80 1.80 1.800 Dry Gas Meter Volume Sampled, cubic feet 143.280 144.550 141.710 143.180 Average Dry Gas Meter Temperature, °F 64.67 76.78 57.92 66.457 Dry Gas Meter Volume Sampled, dscf 119.887 118.125 121.231 119.748 Total Moisture Liquid collected, g 335.5 339.3 325.3 333.367 Volume of Water Vapor, standard cubic feet 15.79 15.97 15.31 15.690 Moisture Content of Stack Gas, % 11.64 11.91 11.21 11.587 Moisture Saturation at Stack Gas Temperature, % 43.31 42.64 39.42 41.790 Dry Mole Fraction 0.8836 0.8809 0.8879 0.884 Carbon Dioxide, % 13.1 13.2 13.1 13.133 Oxygen, % 5.7 5.5 5.9 5.700 Carbon Monoxide & Nitrogen, % 81.2 81.3 81 81.167 Fuel Factor 1.16 1.17 1.15 Dry Molecular Weight, lb/lb-Mole 30.32 30.33 30.33 30.327 Wet Molecular weight, lb/lb-Mole 28.89 28.86 28.95 28.900 Flue Gas Static Pressure, inches of H2O -0.4 -0.5 -0.5 -0.467 Absolute Flue Gas Pressure, inches of Mercury 24.67 24.64 24.89 24.733 Average Stack Gas Temperature, °F 164.39 163.67 160.78 162.947 Average Velocity Head, inches of H2O 0.4720360214 605220.471949798

0353240.444848513

755238 0.463 Average Stack Gas Velocity, feet/second 46.18 46.20 44.46 45.613 Stack Cross-Sectional Area, square feet 533.556 533.556 533.556 533.556 Dry Volumetric Flow Rate, dry scfm 910,807.2 908,360.1 894,178.6904,448.633 Actual Wet Volumetric Flue Gas Flow Rate, acfm 1,478,377.0 1,479,017.2 1,423,314.01,460,236.0 67 Percent Isokinetic of Sampling Rate, % Percent Excess Air, % 36.2 34.5 38.1 36.267 F-Factor, dscfm/MMBtu @ %O2 9633 9604 9638 9,625.000 Round Duct Diameter, inches 0 0 0 Rectangular Duct Width, inches 196 196 196 Rectangular Duct Length, inches 392 392 392 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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