TECHNICAL SUPPORT DOCUMENT 

CARBON MONOXIDE REDESIGNATION REQUEST 

AND MAINTENANCE PLAN 

FOR THE DENVER METROPOLITAN AREA 

January 4, 2000 

Colorado Department of Public Health & Environment 

Air Pollution Control Division 

Technical Services Program 

4300 Cherry Creek Drive South 

Denver, Colorado 80246 
Technical Support Document 

Carbon Monoxide Redesignation Request and Maintenance Plan for the Denver Metropolitan Area 

CDPHEIAPCD/Technical Services Program January 4, 2000 ii 
Technical Support Document 

Carbon Monoxide Redesignation Request and Maintenance Plan for the Denver Metropolitan Area 

Table of Contents 

1. INTRODUCTION .............................................................................................................................................. ! 

I.I. BACKGROUND .................................................................................................... .............................................. I 

I. I. I. National Ambient Air Quality Standards for Carbon Monoxide ............. ... ....... .. .................................. 1 

1.1.2. Health Effects of Carbon Monoxide .. .... .. ................................................................ .... ........... .. .............. I 

1. i . 3. Denver Carbon Monoxide Area Designation History ............................................................................ i 

I. i .4. Denver Metropolitan Attainment/Maintenance Area ................................. ............ .. .... .. ...... .................. 2 

i .1. 5. Topography, Climate, and Air Quality Meteorology ...... .................................................. ............. ....... .4 

1.2. REQUIREMENTS FOR REDESIGNA TION ......... ..... ............................................................................................... 7 

i .2.1. Attainment of the Standard .. ....................... ................... .......... ... .. ....... ............... ................................... 7 

1.2.2. State Implementation Plan Approval .... .. ... ................................ ............. ................................... .. .......... 7 

1.2. 3. Improvement in Air Quality Due to Permanent and Enforceable Emissions Reductions .. .................... 7 

i .2.4. CAA Section 110 and Part D Requirements .......................................................................................... 7 

1.2. 5. Maintenance Plan ................... .. ............... ............................................................ .. ... ......... ....... ............. 7 

2. EMISSION INVENTORIES ............................................................................................................................. 8 

2.1. EMISSION INVENTORIES USED IN THE URBAN AIRSHED MODEL ...................................................................... 8 

2.2. DEMOGRAPl-DC AND TRANSPORTATION DATA .......... .... ................ .................................................. ................. 9 

2.3. RESIDENTIAL WOODBURNING ........................................................................................................................ 10 

2.3. i. Fireplaces emissions calculations (grams/household) ........................................................................ 10 

2.3.2. 2006 and 2013 Stove Device Emission Calculations .............................................................. ............. i2 

2.4. ON-ROAD MOBILE SOURCES .......................................................................................................................... 15 

2.4.1. Control Strategy Recommendations .............................. ....................... ..... ............................... ............ 15 

2.4.2. Vehicle Miles Traveled (VMT) ...... .................... .. ........................... ...... ..... .......... .... .. .................... ....... i 5 

2.4.3. Mobile5b Emission Factor Modeling ............... .................... .. ............. ... .. ... ........... .................. .......... 16 

2.4.4. NLEVCredit Estimate ................. .... .......... ...... ..................................... .. ....... ....................................... i7 

2.4.5. RSD Program ........................................ .. .... .............................. .... ..... ..... ............................................. i 7 

2.4.6. Oxygenated Fuel Program ....................... ...... .. ........ .. .......... .. .................... .. .............................. .. ........ 20 

2.4. 7. Mobile5b Scenario Inputs ............................... ............................................. ................. ....... .. ......... .... . 20 

2.4.8. Carbon Monoxide Emission Factors for 2006 and 2013 ..................................................................... 20 

2.4.9. Emission Inventory Calculations ............ ... .. ..... .. ... .. ............ ... ............................................................. 20 

2.5. NON-ROAD MOBILE SOURCES AND AIRPORTS ............................................................................................... 21 

2.5. i. Revised Emissions Estimates for Denver international Airport ...................................... ............. ....... 21 

2.6. POINT SOURCES ............................................................................................................................................. 24 

2.6.1. Point Source Growth in 2006 and 20i 3 .................................... .. .. .. .......................... .. ...... ............... .... 25 

2.7. TEMPORAL DISTRIBUTION OF DAILY EMISSIONS ........................................................................................... 26 

3. AIR QUALITY MODELING METHODOLOGY ....................................................................................... 27 

3 . 1. OVERVIEW OF MODELING PROCESS .................................................................................................. ............. 27 

3.2. MODEL SELECTION ........................................................................................................................................ 27 

3.3. FLOW CHART OF AIR QUALITY MODELING PROCESS ..................................................................................... 28 

3.4. EPISODE SELECTION ...................................................................................................................................... .30 

3.5. METEOROLOGICAL D ESCRIPTION OF MODELING EPISODES .......................................................................... .31 

3.5. i . Modeling Episode Selection for Maintenance Plan ............................. ......... .. ................. .................... 3 i 

3.5.2. Meteorological Conditions on December 5, i988 - "High" Episode ... .............. .................................. 32 

3.5.3. Meteorological Conditions on January i5, i988- "Second-High" Episode .............................. ......... 32 

3 .6. MODELING DOMAIN ....................................................................................................................................... 32 

3.7. DIAGNOSTIC WIND MODEL (DWM) ................................................................................................. ............. 35 

3.8. URBAN AIRSHED MODEL (UAM) SETUP AND APPLICATION ......................................................................... .36 

3.8. i . Simulation Start and End Times (SIMCONTROL) .......................................... ............. ...... .. ............... 36 

3.8.2. initial Conditions (AiRQUALJTY) .............. ...................................................... ..... .............................. 36 

3.8.3. Other UAM preprocessors ................................................................................................................... 38 

3.9. CAL3QHC MODEL SETUP AND APPLICATION .............................................................................................. 39 

3.9.1. Intersection Selection ............................... .. .... ... ........................................ ..... ...................................... 39 

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3.9.2. CAL3QHC Input data ............. .... ............ ................ .................... .. ................... ................... .. ... ... ......... 45 

3.9.3. Receptor Locations ................................... .......... .... ..................... .......... .................... ........ ....... ... ........ 45 

3.9.4. Vehicle Emission Rates ..... ..... .. .......... ................... ......................... ................ ............. .. ....... .... ... .. ....... 46 

3.9.5. Screening Procedures ..... ...................... ................. ............... ... .. ...... ................ ...... ... .............. ............. 46 

3.9.6. Refined Modeling Procedures ..... ..................... ... .. .. .......................... ........... .. ............... ......... .............. 46 

3.9. 7. Treatment of Calms .. ... .. .................. ........ .. .......... .. .................. ... .. .................... .... .. .. ............ ............... . 47 

3.10. MODEL PERFORMANCE EVALUATION .............................. .............. ..................... .... .................... .. .. ......... .48 

3.10.1. Statistical Performance Measures Required by EPA .................. ........... ..... ....... .... .......... ........... .. ...... .49 

3.10.2. Additional Performance Measures ... ............. ...... ... .............. .. .......... ... ........ ......... ... ........... ...... .. ... ...... 53 

3.10.3. Graphical Measures ..... ....................................... ............... ..... .... ..... ....... ..... ............... .... .......... ... ... ..... 55 

3.10.4. Selection of CO Monitors f or Use in the Performance Evaluation Required by EPA ... ..... ...... .. .. .. ..... 55 

3.10.5. " High " Episode Performance Measures ......... .. .................... .......................... ... ... ....... ...... .. .... ........ ... 63 

4. MODELING-BASED MAINTENANCE DEMONSTRATION .................................................................. 73 

4. 1. DES IGN CONCENTRA TIONS ............. ................................................................................................................ 73 

4.2. CONTROL STRATEGY ASSUMPTIONS .. ........................................... ...................................... ........................... 74 

4.3. UAM AND CAL3QHC RESULTS ............................. ................................ ..... .......... .. .................................. ... 76 

4.4. 2006 AND 2013 BUDGET RELATED EMJSSION INVENTORl ES .................................... ........................... .. ......... 77 

5. MONITORING-BASED ATTAINMENT DEMONSTRATION ................................................................ 85 

5. I. DENVER AREA HISTORlCAL PERSPECTIVE ..... ............................................ ...... .... .......................................... 85 

5.2. CARBON MONOXIDE MONITORlNG NETWORK .. .................................................... .... .. ................................... 85 

5.3. MONITOR1NG-8ASED ATTAINMENT DEMONSTRATION .............. ..... .......................... ...................................... 87 

5.4. QUALITY ASSURANCE PROGRAM ................................................................................................................... 96 

5. 4.1. Internal Quality Assurance Programs .......... ...................... ................. .................... ............................ 96 

5.4.2. &ternal Quality Assurance Programs ...... .... ........... ... .. .. ...... ....... .. ...................... ................ ......... ...... 98 

5.4.3. Results of the Denver Metropolitan Area Precision and Accuracy Program .... ............... .......... .. .. ..... 98 

6. DATA ACCESS .............••.............................•.•....•.......................•......•........................................................... 105 

7. REFERENCES ..............................•..............•...................................••.....................................•.•.................... 107 

8. ENDNOTES (AS REFERENCED IN THE APPROVED DENVER " CO SIP TECHNICAL SUPPORT 

DOCUMENT" ) ........................................................................................................................................................ 109 

INDEX .......................................................•.............................................................................................................. 111 

APPENDIX A - MOBILE SOURCE EMISSIONS MODELING: VMT SUMMARIES BY DISPERSION 

MODELING DOMAIN AND NONATTAINMENT AREA DOMAIN .............•................................................ 113 

APPENDIX B - MOBILE SOURCE EMISSIONS MODELING: MOBILE5B INPUT/OUTPUT AND 

FORTRAN ALGORITHM FOR NLEV CREDIT ESTIMATE ......................................................................... 127 

APPENDIX C - MOBILE SOURCE EMISSIONS MODELING: EMISSION FACTORS ............................ 251 

APPENDIX D - MOBILE SOURCE EMISSIONS MODELING: EMISSION ESTIMATES ........................ 255 

APPENDIX E - URBAN AIRSHED MODELING: HIGH EPISODE 2006 RESULTS (RUN H) .................. 269 

APPENDIX F - URBAN AIRSHED MODELING: HIGH EPISODE 2012 RESULTS (RUN L) ................... 328 

APPENDIX G - URBAN AIRSHED MODELING: HIGH EPISODE 2013 RESULTS (RUN 0) .................. 388 

APPENDIX H - CAL3QHC MODELING ........................................................................................................... .448 

APPENDIX I - FEDERAL REGISTER: MARCH 10, 1997 (VOLUME 62, NUMBER 46) ....•........................ 535 

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APPENDIX J - TEMPORAL DISTRIBUTION OF EMISSIONS ..................................................................... 553 

APPENDIX K - SECTION 110 OF THE CLEAN AIR ACT ............................................................................. 559 

APPENDIX L - DENVER INTERNATIONAL AIRPORT EMISSION INVENTORY .................................. 571 

APPENDIX M - ANALYSIS OF THE PROBABILITY OF A CARBON MONOXIDE EXCEEDANCE IN 

DENVER DURING THE FIRST WEEK OF FEBRUARY FOR THE YEARS 2002 THROUGH 2013 AND 

TWO POSSIBLE LEVELS OF OXYGENATE IN AUTOMOTIVE FUELS BASED ON HISTORICAL 

CARBON MONOXIDE DATA FOR 1975THROUGH1994 ............................................................................. 575 

APPENDIX N-TRANSPORTATION MODELING DOCUMENTATION .................................................... 581 

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List of Tables 

Table 1. Emission inventories for the Denver carbon monoxide Urban Airshed Modeling.Cl) ...... 8 

Table 2. Demographic data used to develop emission inventories (modeling domain) . ................ 9 

Table 3. 2006/2013 Residential woodbuming carbon monoxide emission inventory .................. 10 

Table 4. 2006 Fireplace emission rate variables/results ............................................................... 11 

Table 5. 2013 Fireplace emission rate variables/results ............................................................... 11 

Table 6. 2006 stove device calculations ...................................................................................... 13 

Table 7. 2013 stove device calculations ...................................................................................... 13 

Table 8. 2006 Stove emission calculation variables/results .......................................................... 14 

Table 9. 2013 Stove emission calculation variables/results .......................................................... 14 

Table 10 . Daily VMT totals in the Denver-Boulder carbon monoxide Denver-Boulder Carbon 

Monoxide Nonattainment Area ............................................................................................. 15 

Table 11 . VMT totals in the Denver-Boulder carbon monoxide Urban Airshed Modeling 

domain .................................................................................................................................. 16 

Table 12. Input file in the EPA RSD model to generate the 80% credit file ................................ 18 

Table 13. Data used in model year calculations of eligible vehicles ...... ...................................... 19 

Table 14 . On-road mobile source emission estimates in tons per day (tpd) in the Denver-Boulder 

carbon monoxide Urban Airshed Modeling domain ............................................................ 20 

Table 15 . On-road mobile source emission estimates in tons per day (tpd) in the Denver-Boulder 

Carbon Monoxide Nonattainment Area ................................................................................ 20 

Table 16. Revised emission inventory for Denver International Airport ..................................... 23 

Table 17. Ranking of Denver carbon monoxide episodes - 1988 through 1991 - as determined 

for the approved CO SIP ....................................................................................................... 31 

Table 18. Denver metropolitan area Urban Airshed Modeling Domain ...................................... 33 

Table 19. Comparison of maximum I-hour and 8-hour average carbon monoxide data at CAMP 

and Speer and Auraria between 1993 and 1999 .. .................................................................. 42 

Table 20. Carbon monoxide monitoring sites used in the UAM and CAL3QHC modeling study 

for the Denver CO SIP .................................. ........................................................................ 57 

Table 21. EPA's recommended statistical performance measures for the "high" episode ............ 65 

Table 22. Comparison of modeled vs. observed CO 8-hour average concentrations for the "high" 

episode (Run A) - December 5, 1988 ................................................................................... 65 

Table 23. Comparison of approved emission budgets with emissions estimates that would result 

from the Denver carbon monoxide maintenance plan .......................................................... 77 

Table 24. Combined UAM and CAL3QHC estimates for "high" episode - Run H: Enhanced 

Inspection/Maintenance 240 with new vehicles exempted for their first four years; 1.5% 

oxygenated gasoline; evaluation of up to 80% of the fleet with Remote Sensing Devices 

(80% RSD) ............................................................................................................................ 78 

Table 25. Combined UAM and CAL3QHC estimates for "high" episode - Run L: Enhanced 

Inspection/Maintenance 240 with new vehicles exempted for their first four years; 1.5% 

oxygenated gasoline; evaluation of up to 80% of the fleet with Remote Sensing Devices 

(80% RSD) ............................................................................................................................ 80 

Table 26. Combined UAM and CAL3QHC estimates for "high" episode - Run 0: Enhanced 

Inspection/Maintenance 240 with new vehicles exempted for their first four years; 1.7% 

oxygenated gasoline; evaluation of up to 80% of the fleet with Remote Sensing Devices 

(80% RSD) ............................................................................................................................ 82 

Table 27. 1997 Carbon monoxide data summary for the Denver Metropolitan Area . ................. 88 

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Table 28. 1998 Carbon monoxide data summary for the Denver Metropolitan Area .................. 88 

Table 29. 1999 Carbon monoxide data summary for the Denver Metropolitan Area .................. 89 

Table 30. Carbon monoxide data during the episode on November 30, 1999 .............................. 90 

Table 31. Denver metropolitan area carbon monoxide precision and accuracy probability limits 

(%difference): Welby, Highland .......................................................................................... 99 

Table 32. Denver metropolitan area carbon monoxide precision and accuracy probability limits 

(%difference): Longmont, Boulder2 - YMCA .................................................................. 100 

Table 33. Denver metropolitan area carbon monoxide precision and accuracy probability limits 

(% difference): Boulder Marine St., Denver CAMP .......................................................... 101 

Table 34. Denver metropolitan area carbon monoxide precision and accuracy probability limits 

(%difference): Denver NJH, Denver Carriage ................................................................... 102 

Table 35. Denver metropolitan area carbon monoxide precision and accuracy probability limits 

(%difference): Denver Speer & Auraria, Arvada .............................................................. 103 

Table 36. Temporal allocation factors used to distribute AM-Peak, PM-Peak, and Off-Peak onroad mobile emissions for 2006 and 2013 .......................................................................... 557 

List of Figures 

Figure 1. Denver metropolitan area carbon monoxide (CO) Urban Airshed Model (UAM) 

domain and the Nonattainment Area (NAA) boundary. Once the NAA is redesignated for 

CO, the NAA is known as the Attainment/Maintenace Area. The State is not changing the 

boundaries, only the area's desgination .................................................................................. 3 

Figure 2. Shaded relief map showing the topography in the Denver area ...................................... 5 

Figure 3. Air quality modeling process. The meteorological files and preprocessor files from the 

CO SIP are the basis of the UAM maintenance plan modeling ............................................ 29 

Figure 4. Meteorological observation sites used in developing and evaluating the diagnostic wind 

model for the "high" episode used in the maintenance plan ................................................. 34 

Figure 5. Observed hourly concentration values on November 30, 1999 .................................... 43 

Figure 6. Wind/Carbon Monoxide Roses at the Arvada Site. These show the frequency of 

occurrence of CO concentrations greater than 3 ppm or 8 ppm, as a function of wind speed 

and direction. High CO is largely constrained to the NW quadrant, with wind speeds of 4 

mph or less ............................................................................................................................ 59 

Figure 7. Wind direction and UAM performance are displayed as a function of time for the 

"high" episode. Model performance is based on the difference between hourly monitored 

and modeled CO concentrations; a negative value means the model is under-predicting .... 60 

Figure 8. One-hour (1-hr) time series plots showing observations (boxes) and model estimates 

(lines) at CAMP (CMP) and Welby (WBY) .................. ....................................................... 66 

Figure 9. One-hour (1-hr) time series plots showing observations (boxes) and model estimates 

(Jines) at Carriage (CRG) and NJH ....................................................................................... 67 

Figure 10. Eight-hour (8-hr) time series plots showing observations (boxes) and model estimates 

(lines) at CAMP (CMP) and Welby (WBY) ......................................................................... 68 

Figure 11. Eight-hour (8-hr) time series plots showing observations (boxes) and model estimates 

(Jines) at Carriage (CRG) and NJH ....................................................................................... 69 

Figure 12. UAM 8-hour CO concentration isopleths for the hour during which the maximum 

UAM predicted 8-hour concentration occurred during the "high" episode (December 5, 

1988) . .................................................................................................................................... 70 

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Carbon Monoxide Redesignation Request and Maintenance Plan for the Denver Metropolitan Area 

Figure 13. UAM 1-hour CO concentration isopleths for the hour during which the maximum 

UAM predicted 1-hour concentration occurred during the "high" episode (December 5, 

1988). ···································································································································· 71 

Figure 14. Urban Airshed Model Results for 2006 (simulation "H") ........................................... 79 

Figure 15. Urban Airshed Model Results for 2012 (simulation "L") ........................................... 81 

Figure 16. Urban Airshed Model Results for 2013 (simulation "011) ..... . .. . ............. ..................... 83 

Figure 17. Active carbon monoxide monitoring sites in the Denver metropolitan area from 1997-

1999 ...................................................................................................................................... 86 

Figure 18. Historic trends in ambient CO concentrations at CAMP and Speer and Auraria in 

downtown Denver. ................................................................................................................ 91 

Figure 19. Historic trends in ambient CO concentration at Carriage and NJH in Denver ........... 92 

Figure 20. Historic trends in the ambient CO concentration at Welby and Arvada ..................... 93 

Figure 21. Historic trends in the ambient CO concentration at Highland and Longmont.. .......... 94 

Figure 22. Historic trends in the ambient CO concentration in Boulder at 2320 Marine Street and 

2150 281

h Street .................................................................................................................... 95 

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Carbon Monoxide Redesignation Request and Maintenance Plan for the Denver Metropolitan Area 

2.4. On-Road Mobile Sources 

Estimates for carbon monoxide (CO) emissions from on-road mobile sources are 

based on the Environmental Protection Agency (EPA) Mobile Source Emissions Model -

MOBILE5b. 

2.4.1. Control Strategy Recommendations 

Regional Air Quality Commission Mobile Source Carbon Monoxide Control Strategy 

Recommendation for 2006 and 2013 : 

• l/M 240 program with newest 4 model-year exemption 

• 1.5% oxygenated fuel program for 2006; 1.7 % oxygenated fuel program for 2013 

• 80% Remote Sensing Device (RSD) program 

2.4.2. Vehicle Miles Traveled (VMT) 

The DRCOG 1999-2004 Transportation Improvement Conformity networks were 

utilized as the basis for the vehicle miles traveled (VMT) estimates. DRCOG has revised 

population and household growth estimates since this TIP Conformity analysis was 

complete in August 1998. Incorporating the revised growth rates results in 2006 and 2013 

VMT estimated as follows: 

• 2006 magnitude and distribution ofVMT in the Denver-Boulder NAA 

represented by 2011 DB Network 2020 AC 

• 2013 magnitude and distribution ofVMT in the Denver-Boulder NAA 

represented by 2020 AC Network multiplied by a factor on 1.037 

The VMT totals are summarized in the following two tables. 

Table 10 . Daily VMT totals in the Denver-Boulder carbon monoxide Denver-Boulder 

Carbon Monoxide Nonattainment Area. 

Year AM Peak PM Peak Off-Peak Total 

2006 9,441,436 21 ,234,530 31 ,012,298 61 ,688,264 

2013 10,740,302 24,222,119 36,304,514 71 ,266,935 

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Carbon Monoxide Redesignation Request and Maintenance Plan for the Denver Metropolitan Area 

Table 11. VMT totals in the Denver-Boulder carbon monoxide Urban Airshed Modeling 

domain. 

Year 

2006 

2013 

AM Peak PM Peak Off-Peak Total 

10,179,724 22,873,759 33,706,082 66,759,564 

11,582,081 26,104,812 39,499,790 77, 186,683 

The tabular summaries of vehicle miles traveled by area type and functional 

classification and the ten peak periods are included in Appendix A. 

2.4.3. Mobile5b Emission Factor Modeling 

Elements of Mobile5b Emission Factor Modeling: 

• UM 240 program with newest four model years exempt 

• 1.5% oxygenated fuel program in 2006; 1.7 % oxygenated fuel program in 2013 

• 80% RSD program 

• National Low Emitting Vehicle(NLEV) program commencing in 2001 

• Mechanics training credit 

• The most stringent cut-points available in Mobile5b for an VM 240 program 

2006 VM 240 program on light duty gasoline powered vehicles is characterized as 

follows: 

• Start year (January 1 ): 1982 

• Pre-1981 MYR stringency rate: 20% 

• First model year covered: 1982 

• Last model year covered: 2002 

• Waiver rate (pre-1981): 0% 

• Waiver rate (1981 and newer): 0% 

• Compliance Rate: 98% 

• Inspection type: Test Only 

• Inspection frequency: Biennial 

• Vehicle types covered: LDGV LDGTl LDGT2 

• 1981 & later MYR test type: IM240 test 

• Cutpoints: HC: 0.600 CO: 10.000 NOx: 1.500 

2006 VM 240 program on heavy duty gasoline powered vehicles is characterized as 

follows: 

• Start year (January 1): 1982 

• Pre-1981 MYR stringency rate: 20% 

• First model year covered: 1982 

• Last model year covered: 2002 

• Waiver rate (pre-1981): 0% 

• Waiver rate (1981 and newer): 0.% 

• Compliance Rate: 98.% 

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• Inspection type Test Only 

• Inspection frequency: Biennial 

• Vehicle types covered: HDGV 

• 1981 & later MYR test type: 2500 rpm I Idle 

• Cutpoints: HC: 220.000 CO: 1.200 NOx: 999.000 

Anti-tampering program in 2006 for all gasoline-powered vehicles is characterized as 

follows: 

• Check: ATP 

• Start Model Year: 1982 

• Model Years Covered: 1975-2002 

• Vehicle Classes Covered: LDGV LDGTl LDGT2 HDGV 

• Inspection Type: Test Only 

• Frequency: Biennial 

• Compliance Rate: 98.0% 

• Air pump system disablement: Yes 

• Catalyst removals: Yes 

• Fuel inlet restrictor disablement: No 

• Tailpipe lead deposit test: No 

• EGR disablement: No 

• Evaporative system disablement: No 

• PCV system disablement: No 

• Missing gas caps: Yes 

2013 I/M Programs and Anti-tampering programs are characterized similarly. 

2.4.4. NLEV Credit Estimate 

The emission reduction affects of the National Low Emission Vehicle program on 

light-duty gas vehicles (LDGV) and light-duty truck 1 vehicles (LDGTl) was estimated 

for purposes of this analysis though two Mobile5b emission inventory runs. Mobile5b 

runs are made for high altitude as described above. In order to estimate the NLEV benefit 

on LDGV and LDGTl , a similar run was made for low altitude with the flags set to 

include the NLEV program starting in 2001. The emission factors for LDGV and 

LDGTl vehicles were taken from the low altitude mobile5b runs to replace the same 

emission factors from the high altitude runs. The composite (vehicle mix weighted) 

emission factor was then re-calculated. The FORTRAN algorithm used to accomplish 

these calculations is included in Appendix B. 

2.4.5. RSD Program 

RSD Modeling Inputs: 

• RSD Fleet Coverage Option 2 (Commitment to vehicle coverage) 

• Program type= 5 (Clean screening remote-sensing program) 

• RSD cutpoint .5% CO, 200ppm HC 

• RSD clean screening with l/M 240 final cutpoint effectiveness 

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• 2006 Vehicle Population of 2,459,748 (Based on 2 million vehicles in 1999 with 

3% annual increase) 

• Fleet subject to clean screen = I 00% 

• 80% Clean Screen (80% of vehicle population per vehicle age) 

• Colorado's registration distribution 

Table 12. Input file in the EPA RSD model to generate the 80% credit file. 

000 Clean screen, vehicles projected 2006, 80% rsd 

001 2 Commitment to vehicle coverage 

002 5 Clean screening RSD 

005 Imdata.d 

007 Techl2.d 

015 Im.d 

017 Tech.ct 

034 2 ELIGIBLE CLEAN SCREEN PRE 75 

035 2 ELIGIBLE CLEAN SCREEN 75-80 

036 2 ELIGIBLE CLEAN SCREEN 81-85 

037 2 ELIGIBLE CLEAN SCREEN 86-89 

038 2 ELIGIBLE CLEAN SCREEN 90 + 

039 4 RSD CUTPOINTS AND LEP VALUES (l=.5/200) 

044 2 RSD FINAL CUTPOINT 

000 NUMBER OF VEHICLES ELIGIBLE FOR CLEAN SCREEN 

000 80% RSD 

000 ----------- ---------- 201 120734 96587 TOTAL VEHICLES, VEHICLES ELIGIBLE 0-1 

202 140985 112788 TOTAL VEHICLES, VEHICLES ELIGIBLE 1-2 

203 134224 107379 TOTAL VEHICLES, VEHICLES ELIGIBLE 2-3 

204 146707 117365 TOTAL VEHICLES, VEHICLES ELIGIBLE 3-4 

205 155424 124339 TOTAL VEHICLES, VEHICLES ELIGIBLE 4-5 

206 186547 149238 TOTAL VEHICLES, VEHICLES ELIGIBLE 5-6 

207 180287 144230 TOTAL VEHICLES, VEHICLES ELIGIBLE 6-7 

208 153722 122978 TOTAL VEHICLES, VEHICLES ELIGIBLE 7-8 

209 146709 117367 TOTAL VEHICLES, VEHICLES ELIGIBLE 8-9 

210 100218 80174 TOTAL VEHICLES, VEHICLES ELIGIBLE 9-10 

211 131124 104899 TOTAL VEHICLES, VEHICLES ELIGIBLE 10-11 

212 125860 100688 TOTAL VEHICLES, VEHICLES ELIGIBLE 11-12 

213 108005 86404 TOTAL VEHICLES, VEHICLES ELIGIBLE 12,13 

214 78572 62857 TOTAL VEHICLES, VEHICLES ELIGIBLE 13-14 

215 67328 53863 TOTAL VEHICLES, VEHICLES ELIGIBLE 14-15 

216 60739 48591 TOTAL VEHICLES, VEHICLES ELIGIBLE 15-16 

217 58171 46536 TOTAL VEHICLES, VEHICLES ELIGIBLE 16-17 

218 55307 44246 TOTAL VEHICLES, VEHICLES ELIGIBLE 17-18 

219 52444 41955 TOTAL VEHICLES, VEHICLES ELIGIBLE 18-19 

220 30823 24658 TOTAL VEHICLES, VEHICLES ELIGIBLE 19-20 

221 24506 19605 TOTAL VEHICLES, VEHICLES ELIGIBLE 20-21 

222 18254 14603 TOTAL VEHICLES, VEHICLES ELIGIBLE 21-22 

223 11937 9550 TOTAL VEHICLES, VEHICLES ELIGIBLE 22-23 

224 4885 3908 TOTAL VEHICLES, VEHICLES ELIGIBLE 23-24 

225 1432 1145 TOTAL VEHICLES, VEHICLES ELIGIBLE 24-25 

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Table 13. Data used in model year calculations of eligible vehicles. 

VEHICLE COUNT FOR 2006 

BASED ON 3% INCREASE PER YEAR 

1999 = 2,000,000 

1999 2000 2001 

2010 2011 

2002 2003 2004 2005 2006 2007 2008 2009 

2000000 2060000 2121800 2185454 2251018 2318548 2388105 2459748 2533540 2609546 2687833 

2768468 2851522 

VMT WEIGHTED AVERAGE VEHICLE MIX FOR 2006 

LDGV 

LDGTl 

LDGT2 

HDGV 

VEHICLE AGE 

0.582 

0.221 

0.104 

0.026 

1431573 

543604 

255814 

63953 

TOTALS 2294945 

LDGV* LDGV 

TOTALS 

LDGTl* LDGTl 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

0.049 

0.065 

0.067 

0.074 

0.08 

0.083 

0.082 

0 . 068 

0.065 

0.043 

0.058 

0.052 

0 . 045 

0 . 034 

0.028 

0 . 024 

0.021 

0.019 

0.017 

0.009 

0.007 

0 . 005 

0.003 

0.001 

0.001 

1 

70147 0.058 

93052 0.055 

95915 0 . 044 

105936 0.047 

114526 0.047 

118821 0.078 

117389 0.071 

97347 0.065 

93052 0.062 

61558 0 . 045 

83031 0.056 

74442 0 .06 

64421 0.051 

48673 0 . 035 

40084 0.032 

34358 0 . 031 

30063 0.033 

27200 0.033 

24337 0.033 

12884 0.021 

10021 0.017 

7158 0. 013 

4295 0.009 

1432 0.004 

1432 0 

1431573 1 

* REGISTRATION DISTRIBUTION 

CDPHE'APCD!Technica/ Services Program 

TOTALS 

31529 

29898 

23919 

25549 

25549 

42401 

38596 

35334 

33703 

24462 

30442 

32616 

27724 

19026 

17395 

16852 

17939 

17939 

17939 

11416 

9241 

7067 

4892 

2174 

0 

543604 

LDGT2* LDGT2 

0.058 

0 . 055 

0.044 

0.047 

0 . 047 

0 . 078 

0. 071 

0.065 

0.062 

0.045 

0.056 

0.06 

0.051 

0 . 035 

0.032 

0 . 031 

0.033 

0.033 

0 . 033 

0. 021 

0.017 

0.013 

0 . 009 

0.004 

0 

1 

TOTALS 

14837 

14070 

11256 

12023 

12023 

19953 

18163 

16628 

15860 

11512 

14326 

15349 

13047 

8953 

8186 

7930 

8442 

8442 

8442 

5372 

4349 

3326 

2302 

1023 

0 

255814 

HDGV* 

0.066 

0.062 

0.049 

0.05 

0.052 

0.084 

0.096 

0.069 

0.064 

0.042 

0 . 052 

0.054 

0.044 

0.03 

0.026 

0 . 025 

0.027 

0.027 

0 . 027 

0.018 

0.014 

0. 011 

0.007 

0.004 

0 

1 

January 4, 2000 

HDGV 

TOTALS 

4221 

3965 

3134 

3198 

3326 

5372 

6140 

4413 

4093 

2686 

3326 

3453 

2814 

1919 

1663 

1599 

1727 

1727 

1727 

1151 

895 

703 

448 

256 

0 

63953 

GRAND 

TOTALS 

120734 

140985 

134224 

146707 

155424 

186547 

180287 

153722 

146709 

100218 

131124 

125860 

108005 

78572 

67328 

60739 

58171 

55307 

52444 

30823 

24506 

18254 

11937 

4885 

1 432 

2294945 

19