### Name: Steve Mills

Title: Designated Representative Company: Public Service Company of Colorado Sign Date: 8/31/2010 Name: Patrick Clark Title: Owner Company: Airtech Environmental Services Sign Date: 8/31/2010 Permitted Facility Representative / Date Testing Company Representative / Date 

## Arapahoe Unit 3 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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### Arapahoe Unit 3 2010 HAP ICR 8/31/2010 Facility Information: Arapahoe 2601 South Platte River Drive

Denver CO80223 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: 96OPDE136 Permitted Source ID/Name: Unit 3 Boiler 3 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: Arapahoe Station Unit 3 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 PRB subbituminous 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 #:031.0008.003 FRS #: 110000467129

SCC / Description10100222 External Combustion Boilers - Electric Generation - Bituminous/Subbituminous Coal - Pulverized Coal: Dry Bottom (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 Duct 0 126 50 1 118.03 3 85.5 190.5

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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### Arapahoe Unit 3 2010 HAP ICR 8/31/2010 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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### Arapahoe Unit 3 2010 HAP ICR 8/31/2010

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### Arapahoe Unit 3 2010 HAP ICR 8/31/2010 Sampling / Stack Data Results Summary 

### Location Duct - Method 26A Average Run Number 1 2 3 Test Date 6/1/2010 6/2/2010 6/2/2010 Run Start Time 10:41:00 AM 7:40:00 AM11:01:00 AM
Run Finish Time 2:00:00 PM 10:48:00 AM 2:11:00 PM
Net Run Time, minutes Dry Gas Meter Volume Sampled, dscf 110.818 109.148 107.363 109.110 Moisture Content of Stack Gas, % 12.88 13.08 13.34 13.100 Moisture Saturation at Stack Gas Temperature, % 100.00 100.00 100.00 100.000 Carbon Dioxide, % 12.3 11.7 12 12.000 Oxygen, % 5.9 5.7 6 5.867 Average Stack Gas Temperature, °F 309.33 301.89 305.78 305.667 Dry Volumetric Flow Rate, dry scfm 127,279.5 132,973.4 133,395.8 131,216.233 Actual Wet Volumetric Flue Gas Flow Rate, acfm 260,603.1 269,697.1 272,751.0 267,683.733 Percent Isokinetic of Sampling Rate, % F-Factor, dscfm/MMBtu @ %O2 9576 9592 9636 9,601.333 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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### Arapahoe Unit 3 2010 HAP ICR 8/31/2010 Emissions Summary

Process Run Data 

### Location: Duct - Method 26A Compound: Hydrogen Chloride Average RunNumber 1 2 3 Mass_mg 1.628 0.465 0.348 0.814 lb/mmBtuO2 4.32E-04 1.24E-04 9.66E-05 0.000 

### Compound: Hydrogen Fluoride Average RunNumber 1 2 3 Mass_mg 2.389 1.671 2.042 2.034 lb/mmBtuO2 6.34E-04 4.45E-04 5.67E-04 0.001



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### Arapahoe Unit 3 2010 HAP ICR 8/31/2010 Process Run Data

APCD Run Data

Process Lab Run Data 

### Run Name Value UOM Comments Target Value 1 Gross Load 42.67 MW 0 

### 1 Heat Input 547.68MMBTU/HR 0 1 Main Steam Flow 405.33 KPPH 0 1 Flue Gas Flow Rate 8159.4 KWSCFH 0 

### 1 DSI Injection Rate 20 % 15 2 Gross Load 42.99 MW 0 2 Heat Input 525.34MMBTU/HR 0 

### 2 Main Steam Flow 421.77 KPPH 0 2 Flue Gas Flow Rate 8090.6 KWSCFH 0 2 DSI Injection Rate 20 % 15 

### 3 Gross Load 42.99 MW 0 3 Heat Input 532.66MMBTU/HR 0 3 Main Steam Flow 421.54 KPPH 0 

### 3 Flue Gas Flow Rate 7961.4 KWSCFH 0 3 DSI Injection Rate 20 % 15 1 Heat Input 547.68 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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### Arapahoe Unit 3 2010 HAP ICR 8/31/2010 Sampling / Stack Data Results Detail 

### Location Duct - Method 26A Average Run Number 1 2 3 Test Date 6/1/2010 6/2/2010 6/2/2010 Run Start Time 10:41:00 AM7:40:00 AM11:01:00 AM Run Finish Time 2:00:00 PM10:48:00 AM 2:11:00 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 1.0163 1.0163 1.0163 1.016 Barometric Pressure, inches of Mercury 24.45 24.5 24.5 24.483 Average Orifice Meter Differential, inches H2O 1.56 1.47 1.44 1.490 Dry Gas Meter Volume Sampled, cubic feet 141.820 135.450 136.310 137.860 Average Dry Gas Meter Temperature, °F 103.81 87.69 100.28 97.260 Dry Gas Meter Volume Sampled, dscf 110.818 109.148 107.363 109.110 Total Moisture Liquid collected, g 348 349 351 349.333 Volume of Water Vapor, standard cubic feet 16.38 16.43 16.52 16.443 Moisture Content of Stack Gas, % 12.88 13.08 13.34 13.100 Moisture Saturation at Stack Gas Temperature, % 100.00 100.00 100.00 100.000 Dry Mole Fraction 0.8712 0.8692 0.8666 0.869 Carbon Dioxide, % 12.3 11.7 12 12.000 Oxygen, % 5.9 5.7 6 5.867 Carbon Monoxide & Nitrogen, % 81.8 82.6 82 82.133 Fuel Factor 1.22 1.30 1.24 Dry Molecular Weight, lb/lb-Mole 30.20 30.10 30.16 30.153 Wet Molecular weight, lb/lb-Mole 28.63 28.52 28.54 28.563 Flue Gas Static Pressure, inches of H2O -0.2 -0.2 -0.2 -0.200 Absolute Flue Gas Pressure, inches of Mercury 24.44 24.49 24.49 24.473 Average Stack Gas Temperature, °F 309.33 301.89 305.78 305.667 Average Velocity Head, inches of H2O 0.2600515117 134170.280788695

6007330.285862468

648811 0.276 Average Stack Gas Velocity, feet/second 38.40 39.74 40.19 39.443 Stack Cross-Sectional Area, square feet 113.109 113.109 113.109 113.109 Dry Volumetric Flow Rate, dry scfm 127,279.5 132,973.4 133,395.8131,216.233 Actual Wet Volumetric Flue Gas Flow Rate, acfm 260,603.1 269,697.1 272,751.0267,683.733 Percent Isokinetic of Sampling Rate, % Percent Excess Air, % 37.6 35.4 38.3 37.100 F-Factor, dscfm/MMBtu @ %O2 9576 9592 9636 9,601.333 Round Duct Diameter, inches 0 0 0 Rectangular Duct Width, inches 85.5 85.5 85.5 Rectangular Duct Length, inches 190.5 190.5 190.5 Fw 0 0 0 0.000 Fc 0 0 0 0.000



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