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.

Friday, February 18, 2011 Page 1 of 7
Arapahoe Unit 3 2010 HAP ICR

8/31/2010

Facility Information:

Arapahoe

2601 South Platte River Drive

Denver CO 80223

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 CO 80002

Contact: Patrick Clark

Phone: 303-670-0530

Fax: 303-670-4130

Email: pclark@airtechenv.com

Air Permit Number:

96OPDE136

Permitted Source ID/Name:

3 Unit 3 Boiler

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/NAIS 221112

Sampling Location Information:

Test Parameter Information:

AFS #: 031.0008.003 FRS #: 110000467129

SCC / Description 10100222 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 0 190.5 85.5 118.03 126 50 1 3

Target

Parameter 

Test

Method

Number of

Test Runs

Test Run

Duration

Sample 

Location Points Comments

Duct Hydrogen Fluoride Method 26A 3 180 0

Duct Hydrogen Chloride Method 26A 3 180 0

Friday, February 18, 2011 Page 2 of 7
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.

Friday, February 18, 2011 Page 3 of 7
Arapahoe Unit 3 2010 HAP ICR

8/31/2010

Friday, February 18, 2011 Page 4 of 7
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 

AM

11:01:00 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

Friday, February 18, 2011 Page 5 of 7
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

Friday, February 18, 2011 Page 6 of 7
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 547.68 MMBTU/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 525.34 MMBTU/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 532.66 MMBTU/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 Million Btus/million BTU using CO2 547.68 0

Run Name Value UOM Comments

Target

Value

1 OVERFIRE AIR 0 0

1 DRY SORBENT INJECTION 0 0

1 BAGHOUSE 0 0

Friday, February 18, 2011 Page 7 of 7
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 AM 7:40:00 AM 11:01:00 AM

Run Finish Time 2:00:00 PM 10:48:00 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

13417

0.280788695

600733

0.285862468

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 127,279.5 132,973.4 133,395.8 131,216.233

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, %

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

Friday, February 18, 2011 Page 8 of 7