COLORADO 

ANNUAL MONITORING 

NETWORK PLAN 

2009 - 2010

Prepared by the Air Pollution Control Division 

Technical Services Program 

June 30, 2009 

Table of Contents

INTRODUCTION .................................................................................................................................... 1 

PURPOSE OF THE NETWORK PLAN .............................................................................................. 1 

Overview .......................................................................................................................................... 1 

APCD Monitoring Operations .......................................................................................................... 1 

Network Modification Procedures .................................................................................................... 1 

CARBON MONOXIDE .......................................................................................................................... 14 

Larimer and Weld Counties ........................................................................................................... 14 

Metropolitan Denver Counties ....................................................................................................... 14 

El Paso, Park & Teller Counties .................................................................................................... 14 

Western Counties .......................................................................................................................... 14 

Quality Assurance Checks for Carbon Monoxide Monitors ........................................................... 15 

Planned Changes in Carbon Monoxide Monitoring for 2009 ......................................................... 15 

OZONE ................................................................................................................................................. 16 

Larimer and Weld Counties ........................................................................................................... 16 

Metropolitan Denver Counties ....................................................................................................... 16 

El Paso, Park & Teller Counties .................................................................................................... 17 

Western Counties .......................................................................................................................... 17 

Quality Assurance Checks for Ozone Monitors ............................................................................. 17 

Planned Changes in Ozone Monitoring for 2009/2010 .................................................................. 18 

NITROGEN DIOXIDE ........................................................................................................................... 19 

Metropolitan Denver Counties ....................................................................................................... 19 

Quality Assurance Checks for Oxides of Nitrogen Monitors .......................................................... 19 

Planned Changes in Nitrogen Dioxide Monitoring for 2009/2010 .................................................. 19 

SULFUR DIOXIDE................................................................................................................................ 20 

Metropolitan Denver Counties ....................................................................................................... 20 

Quality Assurance Checks for Sulfur Dioxide Monitors ................................................................. 20 

Planned Changes in Sulfur Dioxide Monitoring for 2009/2010 ...................................................... 20 

METEOROLOGICAL MEASUREMENTS............................................................................................. 21 

Planned Changes in Meteorological Monitoring for 2009/2010 ..................................................... 21 

PARTICULATE MONITORING............................................................................................................. 22 

PM10 Monitoring................................................................................................................................ 22 

Larimer and Weld Counties ........................................................................................................... 22 

Metropolitan Denver Counties ....................................................................................................... 22 

El Paso, Park & Teller Counties .................................................................................................... 22 

Western Counties .......................................................................................................................... 23 

Planned Changes in PM10 Monitoring for 2009/2010 .................................................................... 23 

PM2.5 Monitoring ............................................................................................................................... 24 

Larimer and Weld Counties ........................................................................................................... 24 

Metropolitan Denver Counties ....................................................................................................... 24 

El Paso, Park, Pueblo, Elbert & Teller Counties ............................................................................ 24 

Western Counties .......................................................................................................................... 25 

PM2.5 Sites not intended for NAAQS Comparison ......................................................................... 25 

Planned Changes in PM2.5 Monitoring for 2009/2010 .................................................................... 26 

Total Suspended Particulates and Lead Monitoring......................................................................... 26 

Metropolitan Denver Counties ....................................................................................................... 26 

New Lead NAAQS ......................................................................................................................... 27 

Planned Changes in TSP and Lead Monitoring for 2009/2010 ..................................................... 27 
Quality Assurance Accuracy Audits for Particulate Monitors ........................................................... 27 

Quality Assurance Precision Checks for Particulate Monitors ......................................................... 29 

Appendix A - Carbon Monoxide Site Descriptions ................................................................................ 30 

Appendix B - Ozone Site Descriptions.................................................................................................. 33 

Appendix C - Nitrogen Dioxide Site Descriptions ................................................................................. 37 

Appendix D - Sulfur Dioxide Site Descriptions...................................................................................... 38 

Appendix E - Meteorological Site Descriptions ..................................................................................... 39 

Appendix F - PM10 Site Descriptions .................................................................................................... 42 

Appendix G - PM2.5 Site Descriptions ................................................................................................... 48 

Appendix H - TSP/Lead Site Descriptions ............................................................................................ 52 

Appendix I - National Core (NCore) Monitoring Station ........................................................................ 53 

Table of Tables 

Table 1 - APCD Sites in Operation for 2009 - 2010................................................................................ 3 

Table 2 - Population Projections for 2005 - 2010 ................................................................................. 10 

Table 3 - Precision Checks for Carbon Monoxide in 2008 ................................................................... 15 

Table 4 - Accuracy Audits for Carbon Monoxide in 2008 ..................................................................... 15 

Table 5 - Precision Checks for Ozone in 2008 ..................................................................................... 18 

Table 6 - Accuracy Audits for Ozone in 2008 ....................................................................................... 18 

Table 7 - Precision Checks for Oxides of Nitrogen in 2008 .................................................................. 19 

Table 8 - Accuracy Audits for Oxides of Nitrogen in 2008 .................................................................... 19 

Table 9 - Precision Checks for Sulfur Dioxide in 2008 ......................................................................... 20 

Table 10 - Accuracy Audits for Sulfur Dioxide in 2008 ......................................................................... 20 

Table 12 - Accuracy Audits for Particulates in 2008 ............................................................................. 28 

Table 13 - Precision Checks for Particulates in 2008 ........................................................................... 29 

Table 14 - Parameters and Scale for the Denver Municipal Animal Shelter......................................... 53 

Table 15 - Traffic Information for the Denver Municipal Shelter ........................................................... 54 
INTRODUCTION 

PURPOSE OF THE NETWORK PLAN

The purpose of the Network Plan is to provide an overview of the current Air Pollution Control 

Division’s air quality monitoring network and projected plans for the coming year. This plan shows the 

general reason for monitoring, the location of the monitor, and finally the type and frequency of 

measurements taken at each location. This is the third year that this review has been released to the 

general public for comment prior to its submittal to the U. S. Environmental Protection Agency (EPA) for 

approval. This change was initiated because of a change in Federal Regulations implemented in 

December 2006. 

Overview 

In 2009 the Colorado Air Pollution Control Division (APCD) plans to operate monitors at 62 

locations. In 2008 the APCD operated monitors at 59 separate locations. Particulate monitors including 

Total Suspended Particulates (TSP), Particulate Matter 10 Microns and smaller (PM10), Particulate Matter 

2.5 Microns and smaller (PM2.5) are the most abundant and widespread of monitoring types across the 

state. Currently, there are PM10 monitors at 30 separate locations and PM2.5 monitors at 19 separate 

locations. There are 23 meteorological sites in operation. These sites monitor wind speed, wind direction, 

resultant speed, resultant direction, standard deviation of horizontal wind direction and temperature. 

Three meteorological sites also monitor for relative humidity. Only 9 of the 62 locations will monitor for 

3 or more parameters (with meteorological and PM2.5 measurements counting as only one parameter 

each). Only 3 locations monitored for more than 6 parameters, all of which are in the Denver Metro Area. 

Increasing the amount of automated versus manual monitoring will require modifications to the 

particulate network since in the current network these are primarily manually operated monitors. The 

APCD currently operates one TSP monitor that is used for lead analysis. Only 6 of the 30 PM10 monitors 

are continuous “hourly,” while 12 of the 19 PM2.5 monitors are continuous. This difference reflects the 

age of the technology more than anything else. 

Thirty-seven of the 62 current monitoring sites have been in operation for more than 10 years and 

18 of these have been in operation for 20 or more years. Ten monitoring sites have been in operation for 

more than 30 years. These sites are: Denver CAMP (44 years), Greeley-Hospital (42 years), Alamosa 

Adams State College (39 years), Welby and Arvada (36 years), Pagosa Springs, Lamar Power Plant and 

Steamboat Springs (34 years). Conversely, 24 of the 62 monitoring sites have begun operation since the 

start of the year 2000. 

APCD Monitoring Operations

The APCD attempts to operate all of its monitors on an annual schedule. We attempt to begin 

operation of new monitors in January and to terminate existing monitors in December. Circumstances 

both in and out of our control make that desired schedule generally difficult to achieve. The primary 

reason for this is that the Division does not own either the land or the buildings that most of our monitors 

where most of the monitors are located. 

When modifications to the network are required, the Division will provide EPA Region VIII with 

the appropriate modification forms prior its implementation for their approval. All currently operating 

SLAMS monitors have been approved by EPA and either meet the requirements set forth in Appendices 

A, C, D and E or have received waivers. 

Network Modification Procedures 

Colorado Air Monitoring Network Plan – 2009 –2010 1

The APCD develops changes to its monitoring network in several ways. New monitoring 

locations have been added as the result of community concerns about air quality. An example of this 

would be the PM10 monitors that were established in Rifle and Clifton. Other monitors have been 
established as a result of special studies. Examples of this would be the new ozone monitoring in Aurora, 

Rifle, Cortez, Aspen Park, Rist Canyon, and Palisade. The Denver Firehouse #6 carbon monoxide 

monitor was begun when models showed that it should have elevated carbon monoxide concentrations. 

The most common reason for monitors being removed from the network is that either the 

land/building is being modified, or the area surrounding the monitor is being modified in a way that 

changes the monitoring location. The most current example of this is the Pueblo PM10 monitor. It will 

have to be moved this year because of the construction of a new multi story building on the next lot. 

Monitors are also removed from the network after review of the data shows that the levels have dropped 

to the point where it is no longer reasonable to continue monitoring at that location. Examples of this are 

the reduction of TSP lead monitoring around the state from six monitors to one. Another example of this 

type of change is the termination of carbon monoxide monitoring at the NJH-E location. The carbon 

monoxide concentrations at that location have dropped to the point that the Division, with EPA’s 

approval, felt that the monitor could be better used elsewhere in the system. 

Finally, all monitors are reviewed on a regular basis to determine if they are continuing to meet 

their monitoring objectives. Has the population, land use or vegetation around the monitor changed 

significantly since the monitor was established? If it has is there a “better” location for the monitor? 

All changes to SLAMS monitoring are approved by EPA prior to the change being made. While 

special purpose monitoring does not require EPA approval, all efforts are made to follow siting criteria as 

set forth in 40 CFR 58, Appendix D and Appendix E. 

Colorado Air Monitoring Network Plan – 2009 –2010 2

Table 1 lists the locations and monitoring parameters of each site currently in operation, by 

county alphabetically. 
Table 1 - APCD Sites in Operation for 2009 - 2010 

Colorado Air Monitoring Network Plan – 2009 –2010 3

AQS # Site Name Address Started Ended Latitude Longitude Elevation 

Adams 

08 001 0006 Commerce City 7101 Birch St. 01/2001 39.826007 -104.937438 1,565 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 01/2001 P.O. Neigh Partisol 2025 SLAMS 1/3 

PM2.5 1 01/2001 P.O. Neigh Partisol 2025 SLAMS 1/3 

PM2.5 2 01/2001 P.O. Neigh Partisol 2025 SLAMS 1/6 

PM2.5 3 01/2001 P.O. Neigh TEOM-1400ab SPM Continuous 

PM2.5 5 01/2001 P.O. Neigh SASS Trends Spec 1/3 

PM2.5 Carbon 5 04/2009 P.O. Neigh URG 3000N Trends Spec 1/3 

WS/WD/Temp 1 06/2003 Other Met - One Other Continuous 

08 001 3001 Welby 3174 E. 78th Ave. 07/1973 39.838119 -104.949840 1,554 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 1 07/1973 P.O. Neigh Thermo 48C SLAMS Continuous

SO2 2 07/1973 P.O. Neigh API 100E SLAMS Continuous

NO 2 01/1976 P.O. Urban API 200E Other Continuous

NO2 1 01/1976 P.O. Urban API 200E SLAMS Continuous 

O3 2 07/1973 P.O. Neigh API 400A SLAMS Continuous

WS/WD/Temp 1 01/1975 Other Met - One Other Continuous

PM10 1 07/1990 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

PM10 3 06/1990 P.O. Neigh TEOM-1400ab SLAMS Continuous 

Alamosa 

08 003 0001 Alamosa - ASU 208 Edgemont Blvd 01/1970 37.469391 -105.878691 2,302 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 06/1989 P.O. Neigh SA/GMW-1200 SLAMS 1/1 

08 003 0003 Alamosa Municipal 425 4th St. 04/2002 37.469584 -105.863175 2,301 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 04/2002 P.O. Neigh SA/GMW-1200 SLAMS 1/1 

Arapahoe 

08 005 0002 Highland Reservoir 8100 S. University Blvd 06/1978 39.567887 -104.957193 1,747 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 06/1978 P.O. Neigh API 400A SLAMS Continuous

WS/WD/Temp 1 07/1978 Other Met - One Other Continuous

08 005 0005 Arapahoe Comm. Coll. 6190 S. Santa Fe Dr. 12/1998 39.604399 -105.01526 1,636 

Parameter POC Started Scale Monitor Type Sample 

PM2.5 1 03/1999 P.O. Neigh Partisol 2025 SLAMS 1/3 

08 005 0006 Aurora - East 36001 W Quincy Ave. 04/2009 39.638540 -104.569130 1799 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 04/2009 SPM Region API 400E SPM Continuous

WS/WD/Temp + Other Met - One Other Continuous

Archuleta 

08 007 0001 Pagosa Springs 309 Lewis St. 08/1975 37.268420 -107.009659 2,165 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 3 06/2001 P.O. Neigh SA/GMW-1200 SLAMS 1/1 
AQS # Site Name Address Started Ended Latitude Longitude Elevation 

Colorado Air Monitoring Network Plan – 2009 –2010 4

Boulder 

08 013 0003 Longmont-Municipal 350 Kimbark St. 06/1985 40.164576 -105.100856 1520 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 2 04/1985 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

PM2.5 1 01/1999 P.O. Neigh Partisol 2025 SLAMS 1/3 

PM2.5 3 01/1985 P.O. Neigh TEOM 1400ab SLAMS Continuous 

08 013 0009 Longmont - Main 440 Main St. 11/1989 40.166586 -105.102402 1,519 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 1 11/1989 P.O. Micro Thermo 48C SLAMS Continuous 

08 013 0011 Boulder - Foothills 1405 1⁄2 S. Foothills Parkway 06/1994 39.957159 -105.238513 1,669 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 06/1994 H.C. Urban API 400E SLAMS Continuous 

08 013 0012 Boulder Chamber 2440 Pearl St. 12/1994 40.021097 -105.263382 1,619 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 12/1994 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

PM2.5 1 01/1999 P.O. Neigh Partisol 2025 SLAMS 1/3 

08 013 1001 Boulder CU/Athens 2102 Athens St. 12/1980 40.012969 -105.264212 1,622 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM2.5 3 11/2004 P.O. Neigh TEOM FDMS SPM Continuous 

Delta 

08 029 0004 Delta 560 Dodge St. 08/1993 38.739213 -108.073118 1,511 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 08/1993 P.O. Neigh SA/GMW-1200 SLAMS 1/3 

Denver 

08 031 0002 Denver - CAMP 2105 Broadway 01/1965 39.751184 -104.987625 1,593 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 2 01/1971 P.O. Micro Thermo 48C SLAMS Continuous

SO2 1 01/1967 P.O. Neigh API 100E SLAMS Continuous

NO 1 01/1973 Other API 200E Other Continuous

NO2 1 01/1973 P.O. Neigh API 200E SLAMS Continuous

WS/WD/Temp 1 01/1965 Other Met - One Other Continuous

PM10 1 01/1986 P.O. Micro SA/GMW-1200 SLAMS 1/6 

PM10 2 08/1986 P.O. Micro SA/GMW-1200 SLAMS 1/6 

PM10 3 01/1988 P.O. Micro TEOM-1400ab SLAMS Continuous 

PM2.5 1 01/1999 P.O. Micro Partisol 2025 SLAMS 1/1 

PM2.5 2 09/2001 P.O. Micro Partisol 2025 SLAMS 1/3 

PM2.5 3 01/1999 P.O. Micro TEOM FDMS SLAMS Continuous 

08 031 0013 NJH-East 14th Ave. & Albion St. 01/1983 39.738578 -104.939925 1,620 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM2.5 3 10/2003 P.O. Middle TEOM FDMS SPM Continuous 

08 031 0014 Denver - Carriage 2325 Irving St. 06/1982 39.751761 -105.030681 1,621 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 2 01/1982 P.O. Neigh API 400E SLAMS Continuous

WS/WD/Temp 1 01/1983 Other Met - One Other Continuous

08 031 0017 Denver Visitor Center 225 W. Colfax Ave. 12/1992 39.740342 -104.991037 1,597 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 12/1992 P.O. Middle SA/GMW-1200 SLAMS 1/1 
AQS # Site Name Address Started Ended Latitude Longitude Elevation 

Colorado Air Monitoring Network Plan – 2009 –2010 5

08 031 0019 Denver Firehouse #6 1300 Blake St. 11/1993 39.748163 -105.002564 1,585 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 1 11/1993 P.O. Micro Thermo 48C SLAMS Continuous 

08 031 0021 Auraria Campus Met 12th St. and Auraria Parkway 03/1999 39.746955 -105.003604 1,586 

Parameter POC Started Orient/Scale Monitor Type Sample 

WS/WD/Temp 1 03/1999 Other Met - One Other Continuous 

Relative Humidity 1 03/1999 Other Rotronic Other Continuous 

08 031 0023 Denver - Swansea 4650 Columbine St 07/2002 39.781083 -104.956650 1,583 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM2.5 1 12/2004 P.O. Neigh Partisol 2025 SPM 1/1 

08 031 0025 Denver Municipal 

Animal Shelter 678 S. Jason St. 07/2005 39.704005 -104.998113 1,594 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO (Trace) 1 04/2009 P.O. Neigh Thermo 48C-TLE NCore Continuous 

SO2 (Trace) 1 06/2009 P.O. Neigh Ecotech 9850T NCore Continuous 

NOY + 

O3 1 04/2008 Neigh/Urban API 400A NCore Continuous 

WS/WD/Temp (U) 1 07/2008 P.O. Neigh Met - One NCore Continuous 

Relative Humidity 1 + Rotronic NCore Continuous 

Barometric Pressure 1 + NCore Continuous

Solar Radiation 1 + NCore Continuous

Precipitation 1 + NCore Continuous

Temp (L) 1 07/2008 P.O. Neigh Met - One NCore Continuous 

TSP 1 07/2005 P.O. Neigh TSP SLAMS 1/6 

TSP 2 07/2005 P.O. Neigh TSP SLAMS 1/6 

Pb 1 07/2005 P.O. Neigh TSP SLAMS 1/6 

Pb 2 07/2005 P.O. Neigh TSP SLAMS 1/6 

PM10 1 07/2005 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

PM10 2 07/2005 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

PM10 3 08/2005 P.O. Neigh TEOM-1400ab SLAMS Continuous 

PM2.5 1 10/2007 P.O. Neigh Partisol 2025 NCore 1/6 

PM2.5 3 10/2007 P.O. Neigh TEOM FDMS SPM Continuous 

Douglas 

08 035 0004 Chatfield State Park 11500 N Roxborough Pk Rd 04/2004 39.534488 -105.070358 1,676 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 05/2005 H.C. Urban API 400E SLAMS Continuous 

WS/WD/Temp 1 04/2004 Other Met - One Other Continuous 

PM2.5 1 07/2005 P.O. Neigh Partisol 2025 SPM 1/3 

PM2.5 3 05/2004 P.O. Neigh TEOM 2000 SPM Continuous 

Elbert 

08 039 0001 Elbert County 24950 Ben Kelly Rd. 12/1998 39.231384 -104.634770 2,139 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM2.5 1 05/1999 Back Region Partisol 2025 SLAMS 1/6 

El Paso 

08 041 0013 U. S. Air Force Academy USAFA Rd 640 05/1996 39.958341 -104.817215 1,971 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 06/1996 P.O. Urban ML 8810 SLAMS Continuous 

08 041 0015 Colorado Springs Hwy-24 690 W. Hwy 24 11/1998 39.830895 -104.839243 1,824 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 1 11/1998 P.O. Micro Thermo 48C SLAMS Continuous 

WS/WD/Temp + Other Met – One Other Continuous 
AQS # Site Name Address Started Ended Latitude Longitude Elevation 

Colorado Air Monitoring Network Plan – 2009 –2010 6

08 041 0016 Manitou Springs 101 Banks Pl. 04/2004 38.853097 -104.901289 1,955 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 04/2004 P.O. Neigh API 400E SLAMS Continuous 

08 041 0017 Colorado College 130 W. Cache la Poudre 12/2007 38.848014 -104.828564 1,832 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 12/2007 P.O. Neigh Partisol 2000 SLAMS 1/6 

PM2.5 1 12/2007 P.O. Neigh Partisol 2025 SLAMS 1/3 

PM2.5 3 01/2008 P.O. Neigh TEOM FDMS SPM Continuous 

Fremont 

08 043 0003 Cañon City – City Hall 128 Main St. 10/2004 38.438290 -105.245040 1,626 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 10/2004 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

Garfield 

08 045 0005 Parachute 100 E. 2nd St. 01/1982 38.453654 -108.053269 1,557 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 05/2000 P.O. Neigh SA/GMW-1200 SLAMS 1/3 

08 045 0007 Rifle – Henry Bldg 144 3rd St. 05/2005 39.531813 -107.782298 1,627 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 05/2005 P.O. Neigh SA/GMW-1200 SPM 1/3 

PM2.5 1 09/2008 P.O. Neigh TEOM 1405 SPM Continuous 

PM10 3 09/2008 P.O. Neigh TEOM 1405 SPM Continuous 

PM Course 1 09/2008 P.O. Neigh TEOM 1405 SPM Continuous 

WS/WD/Temp + Other Met - One Other Continuous 

08 045 0012 Rifle - Health 195 W. 14th Ave. 06/2008 39.541820 -107.784125 1,640 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 06/2008 SPM Neigh API 400E SPM Continuous 

Gunnison 

08 051 0004 Crested Butte 603 6th St. 09/1982 38.867595 -106.981436 2,714 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 2 03/1987 P.O. Neigh SA/GMW-1200 SLAMS 1/3 

PM10 3 10/2008 P.O. Neigh SA/GMW-1200 QA Collocated 1/6 

08 051 0007 Mt. Crested Butte 19 Emmons Rd. 07/2005 38.900392 -106.966104 2,866 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 07/2005 P.O. Neigh SA/GMW-1200 SLAMS 1/1 

Jefferson 

08 059 0002 Arvada 9101 W. 57th Ave. 01/1973 39.800333 -105.099973 1,640 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 08/1973 P.O. Neigh API 400E SLAMS Continuous 

WS/WD/temp 1 01/1975 Other Met - One Other Continuous 

08 059 0005 Welch 12400 W. Hwy 285 08/1991 39.638781 -105.139480 1,742 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 08/1991 P.O. Urban API 400A SLAMS Continuous 

WS/WD/temp 1 11/1991 Other Met - One Other Continuous 

08 059 0006 Rocky Flats - N 16600 W. Hwy 128 06/1992 39.912899 -105.188587 1,802 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 09/1992 H.C. Urban API 400E SLAMS Continuous 

WS/WD/temp 1 09/1992 Other Met - One Other Continuous 

08 059 0008 Rocky Flats - SE 9901 Indiana St. 06/1992 39.876390 -105.165611 1,716 

Parameter POC Started Orient/Scale Monitor Type Sample 

WS/WD/temp 1 08/1991 Other Met - One Other Continuous 
AQS # Site Name Address Started Ended Latitude Longitude Elevation 

08 059 0011 NREL 2054 Quaker St. 06/1994 39.743724 -105.177989 1,832 

Parameter POC Started Scale Monitor Type Sample 

O3 1 06/1994 H.C. Urban API 400E SLAMS Continuous 

08 059 0013 Aspen Park 26137 Conifer Rd. 04/2009 39.541515 -105.298410 2,473 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 04/2009 SPM Neigh API 400E SLAMS Continuous 

WS/WD/Temp + Other Met - One Other Continuous 

La Plata 

08 067 0004 Durango-RCH 1235 Camino del Rio 09/1985 37.277298 -107.880928 1,986 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 12/2002 P.O. Neigh API 400E SLAMS Continuous 

Larimer 

08 069 0009 Fort Collins - CSU 251 Edison Dr 12/1998 40.571288 -105.079693 1,524 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 07/1999 P.O. Neigh SA/GMW-1200 SLAMS 1/3 

PM10 3 + P.O. Neigh Thermo 1405 DF SLAMS Continuous 

PM2.5 1 07/1999 P.O. Neigh Partisol 2025 SLAMS 1/3 

PM2.5 3 + P.O. Neigh Thermo 1405 DF SPM Continuous 

08 069 0011 Fort Collins - West 3416 La Porte Ave. 05/2006 40.592543 -105.141122 1,571 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 05/2006 H.C. Urban API 400E SLAMS Continuous 

08 069 0012 Rist Canyon 11835 Rist Canyon Rd. 04/2009 40.642135 -105.275105 2,058 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 04/2009 SPM Urban API 400E SPM Continuous 

WS/WD/Temp 1 04/2009 Other Met - One Other Continuous 

Colorado Air Monitoring Network Plan – 2009 –2010 7

08 069 1004 Fort Collins - Mason 708 S. Mason St. 12/1980 40.577470 -105.078920 1,524 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 1 12/1980 P.O. Neigh Thermo 48C SLAMS Continuous

O3 1 12/1980 P.O. Neigh API 400E SLAMS Continuous

WS/WD/Temp 1 01/1981 Other Met - One Other Continuous

Mesa 

08 077 0017 Grand Junction - Powell 650 South Ave. 02/2002 39.063798 -108.561173 1,398 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 3 01/2005 P.O. Neigh Partisol 2025 SLAMS 1/3 

PM10 4 03/2005 P.O. Neigh Partisol 2000 SPM 1/6 

PM2.5 1 11/2002 P.O. Neigh Partisol 2025 SLAMS 1/6 

PM2.5 3 01/2005 P.O. Neigh TEOM 1400ab SLAMS Continuous 

PM2.5 5 11/2002 P.O. Neigh SASS Supplemental Speciation 1/6 

PM2.5 Carbon 5 04/2009 P.O. Neigh URG 3000N Supplemental Speciation 1/6 

08 077 0018 Grand Junction - Pitkin 645 1⁄4 Pitkin Ave. 01/2004 39.064289 -108.561550 1,398 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 01/2004 P.O. Neigh Met-One BAM SLAMS Continuous 

CO 1 01/2004 P.O. Micro Thermo 48C SLAMS Continuous 

WS/WD/Temp 1 01/2004 Other Met - One Other Continuous 

Relative Humidity 1 01/2004 Other Rotronic Other Continuous 

08 077 0019 Clifton Hwy 141 and D Rd. 10/2006 39.062514 -108.457382 1,413 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 10/2007 P.O. Neigh SA/GMW -1200 SLAMS 1/3 

08 077 0020 Palisade Water Treatment Rapid Creek Rd. 04/2009 39.130575 -108.313835 1,421 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 04/2009 SPM Urban API 400E SLAMS Continuous 

WS/WD/Temp + 04/2009 Other Met - One Other Continuous 
AQS # Site Name Address 

Colorado Air Monitoring Network Plan – 2009 –2010 8

Started Ended Latitude Longitude Elevation 

Montezuma 

08 083 0006 Cortez 106 W. North St. 06/2006 37.349963 -108.587159 1,890 

Parameter POC Started Scale Monitor Type Sample 

O3 1 04/2009 SPM Urban API 400E SLAMS Continuous 

WS/WD/Temp 1 04/2009 Other Met - One Other Continuous 

PM2.5 1 06/2008 SPM Region Patisol 2000 SPM 1/6 

Pitkin 

08 097 0006 Aspen - Library 120 Mill St. 05/2002 39.191040 -106.818864 2,408 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 05/2002 P.O. Neigh SA/GWM 1200 SLAMS 1/3 

PM10 2 05/2002 P.O. Neigh SA/GWM 1200 SLAMS 1/3 

PM10 3 05/2002 P.O. Neigh TEOM-1400ab SLAMS Continuous 

Prowers 

08 099 0001 Lamar Power Plant 100 N. 2nd St. 08/1975 38.090949 -102.613912 1,107 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 2 03/1987 P.O. Neigh SA/GMW-1200 SLAMS 1/1 

08 099 0002 Lamar Municipal 104 E. Parmenter St. 12/1976 38.084688 -102.618641 1,107 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 2 03/1987 P.O. Neigh SA/GMW-1200 SLAMS 1/1 

08 099 0003 Lamar Port of Entry 7100 US Hwy 50. 03/2005 38.113792 -102.626181 1,108 

Parameter POC Started Orient/Scale Monitor Type Sample 

WS/WD/Temp 1 03/2005 Other Met - One Other Continuous 

Pueblo 

08 101 0012 Pueblo Public Works 211 D St. 07/1998 38.263058 -104.612133 1,421 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 07/1998 P.O. Neigh SA/GMW-1200 SLAMS 1/1 

PM2.5 1 02/1999 P.O. Neigh Partisol 2025 SLAMS 1/3 

Routt 

08 107 0003 Steamboat Springs 136 6th St. 09/1975 40.485201 -106.831625 2,054 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 2 03/1987 P.O. Neigh SA/GMW-1200 SLAMS 1/1 

San Miguel 

08 113 0004 Telluride 333 W. Colorado Ave. 03/1990 37.937872 -107.813061 2,684 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 03/1990 P.O. Neigh SA/GMW-1200 SLAMS 1/3 

Summit 

08 117 0002 Breckenridge 501 N. Park Ave. 04/1992 39.491461 --106.047325 2,904 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 1 04/1992 P.O. Neigh SA/GMW-1200 SLAMS 1/3 

Weld 

08 123 0006 Greeley-Hospital 1516 Hospital Rd. 04/1967 40.414877 -104.706930 1,441 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM10 2 03/1987 P.O. Neigh SA/GMW-1200 SLAMS 1/3 

PM2.5 1 02/1999 P.O. Neigh Partisol 2025 SLAMS 1/3 

PM2.5 3 02/1999 P.O. Neigh TEOM - 1400ab SPM Continuous 
Colorado Air Monitoring Network Plan – 2009 –2010 9

AQS # Site Name Address Started Ended Latitude Longitude Elevation 

08 123 0008 Platteville 1004 Main St 12/1998 40.209387 -104.824050 1,469 

Parameter POC Started Orient/Scale Monitor Type Sample 

PM2.5 1 08/1999 P.O. Region Partisol 2025 SLAMS 1/3 

PM2.5 5 08/1999 P.O. Region SASS Supplemental Speciation 1/6 

PM2.5 Carbon 5 04/2009 P.O. Neigh URG 3000N Supplemental Speciation 1/6 

08 123 0009 Greeley -Tower 3101 35th Ave. 06/2002 40.386368 -104.737440 1,484 

Parameter POC Started Orient/Scale Monitor Type Sample 

O3 1 06/2002 P.O. Neigh API 400E SLAMS Continuous 

WS/WD/Temp 1 + Other Met - One Other Continuous 

08 123 0010 Greeley – West Annex 905 10th Ave. 12/2003 40.423432 -104.694790 1,421 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 1 12/2003 P.O. Neigh Thermo 48C SLAMS Continuous 

The following abbreviations were used in Table 1, with orientation (Orient) referring to the reason why 

the monitor was placed in that location, and scale referring to the size of the area that concentrations from 

the monitor represent. 

Orientation Scale

P.O. - Population oriented Micro - Micro-scale 

Back - Background orientation Neigh - Neighborhood Scale 

SPM - Special Projects Monitor Middle - Middle Scale 

H.C. - Highest Concentration Urban - Urban Scale 

Parm - Parameter Code Regional - Regional Scale 

Also included in the above table are listings as “Other” which are meteorological monitors that do not 

include either orientation or scale. The “+” in the “Start” column indicates that the monitor has not been 

installed. . 
Colorado Air Monitoring Network Plan – 2009 - 2010 

Table 2 - Population Projections for 2005 - 2010 

REGIONS/Counties Projected Population Annual Change CO SO2 NOX NOY O3 Met R.H. Precip TSP Pb PM1

July, 2005 July, 2010 00-05 05-10 

COLORADO 4,718,562 5,207,801 1.7% 2.0% 9 3 3 21 23 3 1 1 27 FRONT RANGE 3,862,633 4,250,332 1.8% 1.9% 7 3 3 16 15 2 1 1 9 DNVR-BLDR REGION 2,623,871 2,845,175 1.6% 1.6%  DENVER PMSA 2,337,991 2,546,353 2.0% 1.7% 

 Adams 402,110 452,411 1.9% 2.4% 

08 001 0006 Commerce City 1 1 08 001 3001 Welby 1 1 1 1 1 1 

Arapahoe 534,252 581,897 1.7% 1.7% 

08 005 0002 Highland Reservoir 1 1 08 005 0005 Arapahoe Community College 08 005 0006 Aurora Reservoir + + 

Broomfield 45,755 51,970 --- 2.6% 

Denver 571,848 606,667 0.6% 1.2% 

08 031 0002 Denver CAMP 1 1 1 1 1/C 08 031 0013 Denver NJH 08 031 0014 Denver Carriage 1 1 08 031 0017 Denver Visitor Center 1 08 031 0019 Denver Firehouse #6 1 08 031 0021 Auraria Met 1 1 08 031 0023 Swansea 08 031 0025 Denver Animal Shelter 1 1 + 1 1 1 + 1/C 1/C 1/C 

Douglas 251,418 303,362 6.8% 3.8% 

08 035 0004 Chatfield Reservoir 1 1 

Jefferson 532,608 550,046 0.2% 0.6% 

08 059 0002 Arvada 1 1 08 059 0005 Welch 1 1 08 059 0006 Rocky Flats - N 1 1 08 059 0008 Rocky Flats - SE 1 08 059 0011 NREL 1 08 059 0013 Aspen Park + + 

BOULDER PMSA/Co 285,880 298,822 -0.7% 0.9%  BOULDER PMSA/Co 08 013 0003 Longmont Municipal 1 

08 013 0009 Longmont - Main 1 08 013 0011 Boulder - Foothills 1 08 013 0012 Boulder Chamber 1 
Colorado Air Monitoring Network Plan – 2009 - 2010 

REGIONS/Counties Projected Population Annual Change CO SO2 NOX NOY O3 Met R.H. Precip TSP Pb PM1

July, 2005 July, 2010 00-05 05-10 

08 013-1001 Boulder CU/Athens 

 NORTH FRONT RANGE 499,962 566,072 2.7% 2.5%  FORT COLLINS MSA 271,951 299,040 1.4% 1.9% 

08 069 0009 Fort Collins - CSU 1 08 069 0011 Fort Collins - West 1 08 069 0012 –Rist Canyon + + 08 069 1004 Fort Collins - Mason 1 1 1 

 GREELEY MSA 228,011 267,032 4.4% 3.2% 

08 123 0006 Greeley Hospital 1 08 123 0008 Platteville 08 123 0009 Greeley - Tower 1 + 08 123 0010 Greeley - West Annex 1 

 COLO. SPRINGS MSA 587,696 674,103 1.6% 2.8% 

El Paso 565,350 649,217 1.7% 2.8% 

08 041 0013 USAFA 1 08 041 0015 Colorado Springs - Hwy-24 1 + 08 041 0016 Manitou Springs 1 08 041 0018 Colorado College 1 

Teller 22,346 24,886 1.1% 2.2% 

 PUEBLO MSA 151,104 164,982 1.2% 1.8% 

08 101 0012 Pueblo Public Works 1 

 WESTERN SLOPE 513,332 589,836 1.9% 2.8% 

REGION 9 87,019 97,620 1.5% 2.3% 

Archuleta 11,716 14,131 3.2% 3.8% 

08 007 0001 Pagosa Springs 1 

Dolores 1,846 2,076 0.0% 2.4% 

La Plata 48,019 53,282 1.5% 2.1% 

08 067 0004 Durango - RCH 1 

Montezuma 24,862 27,523 0.8% 2.1% 

08 083 0006 Cortez 1 

San Juan 576 608 0.6% 1.1% 

REGION 10 94,835 107,287 1.8% 2.5% 

Delta 30,257 34,200 1.6% 2.5% 

08 029 0004 Delta 1 

Gunnison 14,264 15,233 0.4% 1.3% 

08 051 0004 Crested Butte 1/C 08 051 0007 Mt. Crested Butte 1 

Hinsdale 821 918 0.8% 2.3% 

Montrose 37,880 43,875 2.4% 3.0% 
Colorado Air Monitoring Network Pl 2010 an – 2009 - 

REGIONS/Counties Projected Population Annual Change CO SO2 NOX NOY O3 Met R.H. Precip TSP Pb PM1

July, 2005 July, 2010 00-05 05-10 

Ouray 4,303 4,781 2.7% 2.1% 

San Miguel 7,310 8,280 1.9% 2.5% 

 08 113 0004 Telluride 1 

REGION 11 222,739 260,304 2.1% 3.2% 

Garfield 50,673 64,097 2.7% 4.8% 

08 045 0005 Parachute 1 08 045 0007 Rifle - Henry Building 1 1 08 045 0012 Rifle - Health 1 

Mesa 130,662 150,504 2.1% 2.9% 

08 077 0017 Grand Junction - Powell 1/C 08 077 0018 Grand Junction - Pitkin 1 1 1 1 08 077 0019 Clifton 1 08 077 0020 Palisade Water Treatment 1 1 

Moffat 13,426 14,424 0.4% 1.4% 

Rio Blanco 6,073 6,651 0.3% 1.8% 

Routt 21,905 24,628 1.7% 2.4% 

 08 107 0003 Steamboat Springs 1 

REGION 12 108,739 124,625 1.8% 2.8% 

Eagle 49,375 58,196 2.6% 3.3% 

Grand 13,906 15,920 1.5% 2.7% 

Jackson 1,531 1,584 -0.6% 0.7% 

Pitkin 16,420 17,427 0.6% 1.2% 

08 097 0006 Aspen - Library 1/C 

Summit 27,507 31,498 1.3% 2.7% 

 08 117 0002 Breckenridge 1 

 CENTRAL MTNS. 131,841 145,235 0.9% 2.0% 

CLR CRK. & GILPIN 14,514 15,737 0.5% 1.6% 

Clear Creek 9,510 10,242 0.3% 1.5% 

Gilpin 5,004 5,495 0.9% 1.9% 

Park 16,595 19,616 2.5% 3.4% 

REGION 13 76,529 83,284 0.6% 1.7% 

Chaffee 16,889 17,941 0.7% 1.2% 

Custer 3,964 4,599 2.3% 3.0% 

Fremont 47,727 51,454 0.5% 1.5% 

08 043 0003 Cañon City - City Hall 1 

Lake 7,949 9,290 0.1% 3.2% 

REGION 14 24,203 26,598 0.9% 1.9% 

Huerfano 7,932 8,771 0.2% 2.0% 

Las Animas 16,271 17,827 1.3% 1.8% 
Colorado Air Monitoring Network Plan – 2009 - 2010 

REGIONS/Counties Projected Population Annual Change CO SO2 NOX NOY O3 Met R.H. Precip TSP Pb PM1

July, 2005 July, 2010 00-05 05-10 

 SAN LUIS VALLEY 48,506 50,608 0.9% 0.9% 

 Alamosa 15,765 16,692 0.8% 1.1% 

08 003 0001 Alamosa - ASC 1 08 003 0003 Alamosa - Municipal 1 

Conejos 8,586 8,881 0.4% 0.7% 

Costilla 3,628 3,767 -0.2% 0.8% Mineral 946 1,029 2.6% 1.7% 

Rio Grande 13,043 13,263 1.0% 0.3% 

Saguache 6,538 6,976 1.9% 1.3% 

 EASTERN PLAINS 162,250 171,790 0.4% 1.1% 

REGION 1 72,165 77,354 0.6% 1.4% 

Logan 21,605 23,327 0.7% 1.5% 

Morgan 28,348 31,241 0.8% 2.0% 

Phillips 4,631 4,745 0.7% 0.5% 

Sedgwick 2,667 2,705 -0.6% 0.3% 

Washington 4,936 4,990 0.1% 0.2% 

Yuma 9,978 10,346 0.2% 0.7% 

REGION 5 38,693 41,884 1.1% 1.6% 

Cheyenne 2,120 2,068 -1.0% -0.5% 

Elbert 22,786 25,848 2.4% 2.6% 

08 035 0001 Elbert County 

Kit Carson 7,882 8,002 -0.3% 0.3% 

Lincoln 5,905 5,966 -0.9% 0.2% 

REGION 6 51,392 52,552 -0.4% 0.4% 

Baca 4,263 4,128 -1.1% -0.6% 

Bent 6,314 6,432 1.1% 0.4% 

Crowley 5,740 6,235 0.8% 1.7% 

Kiowa 1,533 1,501 -1.1% -0.4% 

Otero 19,569 19,971 -0.7% 0.4% 

Prowers 13,973 14,285 -0.6% 0.4% 

08 099 0001 Lamar Power Plant 1 08 099 0002 Lamar - Municipal 1 08 099 0003 Lamar Port of Entry 1 

+ - indicates monitors that will be installed in 2009. C - Collocated monitors S - SASS PM10 monitor 
CARBON MONOXIDE 

In 2009 as in 2008 the APCD will operate nine carbon monoxide monitors. The levels have 

declined from a statewide maximum 8-hour value of 48.1 ppm in 1973 to a value of 3.1 ppm in 2008. The 

level of the standard has not been exceeded since 1999. The carbon monoxide monitors currently operated 

by the APCD are associated with State Implementation Plan requirements. 

Larimer and Weld Counties 

Larimer and Weld counties have a population of 532,759 (July 2007 population estimates), an 

increase of 23.2 percent since the 2000 Census. The two major urban centers are Fort Collins in Larimer 

County and Greeley in Weld County. Larimer County has irrigated farmland in the eastern half while the 

western half is mountainous. Weld County is predominantly grassland and irrigated farmland. Motor 

vehicle activity is a major source of pollutants. However, there are several small industries and 

manufacturing processes located within the two counties. These industries include a brewery, power 

plants, cement plants, mining, electronics and film manufacturing facilities and rock quarries. 

The carbon monoxide monitors in this area are: 

08 069-1004 Fort Collins, 708 S. Mason Street 

08 123 0010 Greeley -West Annex, 905 10th Avenue 

Metropolitan Denver Counties 

This area includes the Front Range Counties of Adams, Arapahoe, Boulder, Broomfield, Clear 

Creek, Douglas, Gilpin, Jefferson and Denver. The population of the area is 2,749,032 (July 2007 

population estimates). This is an increase of 12 percent from the 2000 census. Carbon monoxide 

monitoring is conducted only in the Denver metropolitan area. This consists of all of Denver County, the 

western half of Adams and Arapahoe counties, most of Boulder and Jefferson counties, the northern 

portion of Douglas County and none of Clear Creek and Gilpin counties. 

The carbon monoxide monitors in this area are: 

08 001 3001 Welby, 3174 E. 78th Avenue 

08 013 0009 Longmont -Main, 440 Main Street 

08 031 0002 Denver CAMP, 2105 Broadway 

08 031 0019 Denver Firehouse #6, 1300 Blake Street 

08 031 0025 Denver Municipal Animal Shelter, 678 S. Jason Street 

El Paso, Park & Teller Counties 

This area has a population of 617,864 according to the July 2007 population estimate this is an 

increase of 12.0 percent from the 2000 census. It is a very popular tourist area with rapid urban growth. 

The land usage varies from open prairies in eastern El Paso County to very mountainous in Teller and 

Park Counties. Only El Paso County has a large urbanized area, Colorado Springs, with a population of 

394,177 according to the July 2007 estimate. This is an increase of 9.2 percent since the 2000 census. The 

City of Colorado Springs and El Paso County both operate separate monitoring networks that are not 

included as a part of this report. 

The carbon monoxide monitors in this area are: 

 08 041 0015 Colorado Springs - Hwy-24, 690 W. Highway 24 

Western Counties 

Colorado Air Monitoring Network Plan – 2009 - 2010 14

The Western Slope consists of the 21 counties west of the Continental Divide. The population of 

the area is 579,813 (July 2007 population estimate). This is an increase of 14.4 percent over the 2000 

census. However, the population is not evenly distributed among the counties and ranges from Mesa 
County with 140,416 to San Juan County with only 571 according to the July 2007 estimate. Short-term 

special purpose monitoring for carbon monoxide has been done in Summit County at Vail and near the oil 

shale projects of Rio Blanco County. Grand Junction is the largest city on the western slope with a 

population of 53,662 (July 2007 estimate). This is an increase of 27.8 percent from the 2000 census. 

The carbon monoxide monitors in this area are: 

08 077 0018 Grand Junction-Pitkin, 6451⁄4 Pitkin Avenue 

Quality Assurance Checks for Carbon Monoxide Monitors 

The APCD staff performs two types of gaseous analyzer performance audits, assessment audits 

and accuracy audits. These audits challenge the analyzer with pollutant gases of known concentration 

within the range of the analyzer. The following table shows the number of these audits conducted on the 

carbon monoxide analyzers for 2008. 

The APCD Quality Assurance staff conducts audits on all of the carbon monoxide instruments at 

least twice per year. The APCD Field staff conducts precision checks nominally once every two weeks. 

The details and minimum standards for this program are set out in the Code of Federal Regulations (Part 

58 Ambient Air Quality Surveillance). A complete description of the procedures and the results are 

available from the APCD. 

Table 3 - Precision Checks for Carbon Monoxide in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

Welby 6 7 7 7 

Longmont 6 7 6 6 

CAMP 6 8 8 7 

Firehouse 6 8 6 6 

Highway 24 7 7 7 7 

Ft Collins 6 7 6 6 

Grand Junction 7 6 7 7 

Greeley - Annex 6 7 6 6 

Table 4 - Accuracy Audits for Carbon Monoxide in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

Welby 1 1 

Longmont 1 1 

CAMP 1 1 

Firehouse 1 1 

Highway 24 1 1 1 

Ft Collins 1 1 

Grand Junction 1 1 

Greeley - Annex 1 1 1 

Planned Changes in Carbon Monoxide Monitoring for 2009 

Colorado Air Monitoring Network Plan – 2009 - 2010 15

None 
OZONE 

On March 12, 2008, the U.S. Environmental Protection Agency released the new level of the 

National ambient ozone standard. The change in the level was from 0.08 ppm as an 8-hour average to 

0.075 ppm. This made a significant change in the number of ozone monitors that exceed the 3-year 

average 8-hour concentration standard. The following locations have exceeded the new level: Highland 

Reservoir, Boulder - Foothills, Chatfield Reservoir, Arvada, Rocky Flats, NREL Solar Radiation 

Research, Welch Fort Collins-West and Greeley - Tower. The following monitors are listed as marginal 

as they are close to exceeding the level of the standard but have not exceeded the standard in the past 

three years: Fort Collins, Denver Carriage, USAF Academy and Manitou Springs. The only monitors 

operated by the CDPHE that are not close to exceeding the level of the new standard are the Denver 

CAMP and Welby locations. 

The non-CDPHE monitor in Colorado that has 3-year average concentrations greater than the 

new standard is at Rocky Mountain National Park. The ozone monitors operated at Mesa Verde National 

Park and the Shamrock Mine site located northeast of Bayfield, Colorado are listed as marginal for being 

near to the level of the standard. 

Larimer and Weld Counties 

Larimer and Weld counties have a population of 532,759 (July 2007 population estimates), an 

increase of 23.2 percent since the 2000 Census. The two major urban centers are Fort Collins in Larimer 

County and Greeley in Weld County. Larimer County has irrigated farmland in the eastern half while the 

western half is mountainous. Weld County is predominantly grassland and irrigated farmland. Motor 

vehicle activity is a major source of pollutants. However, there are several small industries and 

manufacturing processes located within the two counties. These industries include a brewery, power 

plants, cement plants, mining, electronics and film manufacturing facilities and rock quarries. 

The ozone monitors in this area are: 

08 069 0011 Fort Collins-West, 3416 LaPorte Ave. 

08 069 0012 Rist Canyon, 11838 Rist Canyon Road 

08 069 1004 Fort Collins-Mason, 708 S. Mason Street 

08 123 0009 Greeley-Tower, 3101 35th Avenue 

Metropolitan Denver Counties 

This area includes the Front Range Counties of Adams, Arapahoe, Boulder, Broomfield, Clear 

Creek, Douglas, Gilpin, Jefferson and Denver. The population of the area is 2,749,032 (July 2007 

population estimates). This is an increase of 12 percent from the 2000 census. The Denver metropolitan 

area consists of all of Denver County, the western half of Adams and Arapahoe counties, most of Boulder 

and Jefferson counties, the northern portion of Douglas County and none of Clear Creek and Gilpin 

counties. Only Adams, Arapahoe, Boulder, Douglas, Jefferson and Denver Counties have ozone monitors. 

The ozone monitors in this area are: 

 08 001 3001 Welby, 3174 E. 78th Avenue 

 08 005 0002 Highland Reservoir, 8100 S. University Boulevard 

 08 005 0006 Aurora-East, 36001 Quincy Avenue 

 08 031 0011 Boulder-Foothills, 1405 1⁄2 S. Foothills Parkway 

 08 031 0014 Denver-Carriage, 2325 Irving Street 

 08 031 0025 Denver Municipal Animal Shelter, 678 S. Jason Street 

 08 035 0004 Chatfield State Park, 11500 N. Roxborough Park Road 

 08 059 0002 Arvada, 9101 W. 57th Avenue 

Colorado Air Monitoring Network Plan – 2009 - 2010 16

 08 059 0005 Welch, 12400 W. Hwy 285 
 08 059 0006 Rocky Flats-N, 16600 W. Hwy 128 

 08 059 0011 NREL, 2054 Quaker Street 

 08 059 0013 Aspen Park, 26137 Conifer Road 

El Paso, Park & Teller Counties 

This area has a population of 617,864 according to the July 2007 population estimate this is an 

increase of 12.0 percent from the 2000 census. It is a very popular tourist area with rapid urban growth. 

The land usage varies from open prairies in eastern El Paso County to very mountainous in Teller and 

Park Counties. Only El Paso County has a large urbanized area, Colorado Springs, with a population of 

394,177 according to the July 2007 estimate. This is an increase of 9.2 percent since the 2000 census. In 

addition, the City of Colorado Springs and El Paso County both operate separate monitoring networks 

that are not included as a part of this report. 

The ozone monitors in this area are: 

 08 041 0013 U. S. Air Force Academy, USAFA Road 640 

 08 041 0016 Manitou Springs, 101 Banks Place 

Western Counties 

The Western Slope consists of the 21 counties west of the Continental Divide. The population of 

the area is 579,813 (July 2007 population estimate). This is an increase if 14.4 percent over the 2000 

census. However, the population is not evenly distributed among the counties and ranges from Mesa 

County with 140,416 to San Juan County with only 571 according to the July 2007 estimate. Short-term 

special purpose monitoring for ozone has been done in Summit County at Vail and near the oil shale 

projects of Rio Blanco County. Grand Junction is the largest city on the western slope with a population 

of 53,662 (July 2007 estimate). This is an increase of 27.8 percent from the 2000 census. 

The ozone monitors in this area are: 

 08 045 0012 Rifle-Health, 195 W. 14th Avenue 

 08 077 0020 Palisade Water Treatment, Hwy 141 and D Road 

 08 083 0006 Cortez, 106 W. North Street 

Quality Assurance Checks for Ozone Monitors 

The APCD staff performs two types of gaseous analyzer performance audits, assessment audits 

and accuracy audits. These audits challenge the analyzer with pollutant gases of known concentration 

within the range of the analyzer. The following table shows the number of these audits conducted on the 

ozone analyzers for 2008. 

The APCD Quality Assurance staff conducts audits on all of the ozone instruments at least twice 

per year. The APCD Field staff conducts precision checks nominally once every two weeks. The details 

and minimum standards for this program are set out in the Code of Federal Regulations (Part 58 Ambient 

Air Quality Surveillance). A complete description of the procedures and the results are available from the 

APCD. 

Colorado Air Monitoring Network Plan – 2009 - 2010 17
Table 5 - Precision Checks for Ozone in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

Welby 6 7 7 7 

Highlands 7 1 

Boulder - Foothills 6 7 6 6 

CAMP 1 

Carriage 6 7 6 6 

Denver Animal Shelter 4 7 7 

Chatfield 6 6 6 6 

Air Force Academy 7 6 7 7 

Manitou 7 7 7 7 

Arvada 6 6 6 6 

Welch 8 7 7 7 

Rocky Flats - N. 6 6 6 6 

NREL 6 6 8 6 

Ft. Collins - West 7 6 6 6 

Ft. Collins - Mason 6 6 6 6 

Greeley - Tower 6 8 6 6 

Table 6 - Accuracy Audits for Ozone in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

Welby 1 1 

Highlands 1 

Boulder - Foothills 1 1 

CAMP 1 

Carriage 1 1 

Chatfield 1 1 

Air Force Academy 1 1 1 

Manitou 1 1 1 

Arvada 1 1 

Welch 1 1 

Rocky Flats - N. 1 1 1 

NREL 1 

Ft. Collins - West 1 1 

Ft. Collins - Mason 1 1 

Greeley - Tower 1 1 

Planned Changes in Ozone Monitoring for 2009/2010 

1) Possible installation of additional monitors in western Colorado in 2010 to address oil and 

gas development concerns. 

2) Review of monitoring sites in North Front Range for possible enhancement. 

Colorado Air Monitoring Network Plan – 2009 - 2010 18

3) Possible installation of new site in the Pueblo area in 2010 to meet possible new Federal 

monitoring requirements. 
 NITROGEN DIOXIDE 

The Air Pollution Control Division has monitored nitrogen dioxide at eight locations in Colorado. 

All but two of these locations are no longer operating. Only the CAMP monitor has ever approached the 

standard of 0.053 ppm. It recorded 0.052 in 1975, 1976 1979 and in 1983. In the past 20 years the levels 

have been declining and in the past three years the levels have been reduced to nearly one half of the 

standard. 

Metropolitan Denver Counties 

This area includes the Front Range Counties of Adams, Arapahoe, Boulder, Broomfield, Clear 

Creek, Douglas, Gilpin, Jefferson and Denver. The population of the area is 2,749,032 (July 2007 

population estimates). This is an increase of 12 percent from the 2000 census. The Denver metropolitan 

area consists of all of Denver County, the western half of Adams and Arapahoe counties, most of Boulder 

and Jefferson counties, the northern portion of Douglas County and none of Clear Creek and Gilpin 

counties. 

The nitrogen dioxide monitors in this area are: 

08 001 3001 Welby, 3174 E. 78th Avenue 

08 031 0002 Denver-CAMP, 2105 Broadway 

Quality Assurance Checks for Oxides of Nitrogen Monitors 

The APCD staff performs two types of gaseous analyzer performance audits, assessment audits 

and accuracy audits. These audits challenge the analyzer with pollutant gases of known concentration 

within the range of the analyzer. The following table shows the number of these audits conducted on the 

oxides of nitrogen analyzers for 2007. 

The APCD Quality Assurance staff conducts audits on all of the oxides of nitrogen instruments at 

least twice per year. The APCD Field staff conducts precision checks nominally once every two weeks. 

The details and minimum standards for this program are set out in the Code of Federal Regulations (Part 

58 Ambient Air Quality Surveillance). A complete description of the procedures and the results are 

available from the APCD. 

Table 7 - Precision Checks for Oxides of Nitrogen in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

CAMP 3 6 4 3 

Welby 5 7 7 7 

Table 8 - Accuracy Audits for Oxides of Nitrogen in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

CAMP 1 1 

Welby 1 1 

Planned Changes in Nitrogen Dioxide Monitoring for 2009/2010 

Colorado Air Monitoring Network Plan – 2009 - 2010 19

1) Addition of NOY analyzer at the Denver Municipal Animal Shelter to meet NCore 

requirements. 
SULFUR DIOXIDE 

The Air Pollution Control Division has monitored sulfur dioxide at eight locations in Colorado. 

All but two of these locations are no longer operating. Sulfur dioxide has never approached the level of 

any of the sulfur dioxide standards even in the mid-1970’s, when the levels were at their highest; they 

were generally less than one half of the level of the standard. The primary reason for these low levels is 

that what coal fired industry there is in Colorado uses low sulfur coal for combustion. In 2009 a new 

trace/precursor-level sulfur dioxide monitor will be established as a part of the NCore monitoring at the 

Denver Animal Shelter. 

Metropolitan Denver Counties 

This area includes the Front Range Counties of Adams, Arapahoe, Boulder, Broomfield, Clear 

Creek, Douglas, Gilpin, Jefferson and Denver. The population of the area is 2,749,032 (July 2007 

population estimates). This is an increase of 12 percent from the 2000 census. The Denver metropolitan 

area consists of all of Denver County, the western half of Adams and Arapahoe counties, most of Boulder 

and Jefferson counties, the northern portion of Douglas County and none of Clear Creek and Gilpin 

counties. 

The sulfur dioxide monitors in this area are: 

08 001 3001 Welby, 3174 E. 78th Avenue 

08 031 0002 Denver-CAMP, 2105 Broadway 

08 031 0025 Denver Municipal Animal Shelter, 678 S. Jason Street 

Quality Assurance Checks for Sulfur Dioxide Monitors 

The APCD staff performs two types of gaseous analyzer performance audits, assessment audits 

and accuracy audits. These audits challenge the analyzer with pollutant gases of known concentration 

within the range of the analyzer. The following table shows the number of these audits conducted on the 

sulfur dioxide analyzers for 2008. 

The APCD Quality Assurance staff conducts audits on all of the sulfur dioxide instruments at 

least twice per year. The APCD Field staff conducts precision checks nominally once every two weeks. 

The details and minimum standards for this program are set out in the Code of Federal Regulations (Part 

58 Ambient Air Quality Surveillance). A complete description of the procedures and the results are 

available from the APCD. 

Table 9 - Precision Checks for Sulfur Dioxide in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

CAMP 6 6 8 7 

Welby 6 7 7 7 

Table 10 - Accuracy Audits for Sulfur Dioxide in 2008 

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter 

CAMP 1 1 

Welby 1 1 

Planned Changes in Sulfur Dioxide Monitoring for 2009/2010 

Colorado Air Monitoring Network Plan – 2009 - 2010 20

1) None 
METEOROLOGICAL MEASUREMENTS 

Meteorological measurements taken by the APCD consist of Wind Speed, Wind Direction, 

Temperature and Humidity. The wind speed and direction measurements are made as both scalar and 

vector averages. The last measurement that is made at the meteorological sites is the standard deviation of 

horizontal wind direction. This is a calculation, not a direct measurement of the variation of wind 

direction over time. 

The meteorological monitors are: 

08 001 0006 Commerce City, 7101 Birch Street 

08 001 3001 Welby, 3174 E. 78th Avenue 

08 005 0002 Highland Reservoir, 8100 S. University Boulevard 

08 005 0006 Aurora-East, 36001 Quincy Avenue 

08 031 0002 Denver-CAMP, 2105 Broadway 

08 031 0014 Denver-Carriage, 2325 Irving Street 

08 031 0021 Auraria Campus Met, 12th and Auraria Parkway 

08 031 0025 Denver Municipal Animal Shelter, 678 S. Jason Street 

08 035 0004 Chatfield State Park, 11500 N. Roxborough Park Road 

08 059 0002 Arvada, 9101 W. 57th Avenue 

08 059 0005 Welch, 12400 W. Hwy 285 

08 059 0006 Rocky Flats-N, 16600 W. Hwy 128 

08 059 0008 Rocky Flats-SE, 9901 Indiana Street 

08 059 0013 Aspen Park, 26137 Conifer Road 

08 069 0012 Rist Canyon, 11838 Rist Canyon Road 

08 069 1004 Fort Collins-Mason, 708 S. Mason Street 

08 077 0018 Grand Junction-Pitkin, 645 1⁄4 Pitkin Avenue 

08 077 0020 Palisade Water Treatment, Hwy 141 and D Road 

08 099 0003 Lamar Port of Entry, 7100 US Hwy 50 

Planned Changes in Meteorological Monitoring for 2009/2010 

1) Elimination of the Rocky Flats SE site at the end of 2009. 

2) Installation of sensors at the Greeley-Weld County Tower site. 

3) Installation of sensors at the Colorado Springs - Hwy 24 site. 

Colorado Air Monitoring Network Plan – 2009 - 2010 21

4) Installation of additional sensors at the Denver Municipal Animal Shelter site. 
PARTICULATE MONITORING 

PM10 Monitoring 

Larimer and Weld Counties 

Larimer and Weld counties have a population of 532,759 (July 2007 population estimates), an 

increase of 23.2 percent since the 2000 Census. The two major urban centers are Fort Collins in Larimer 

County and Greeley in Weld County. Larimer County has irrigated farmland in the eastern half while the 

western half is mountainous. Weld County is predominantly grassland and irrigated farmland. Motor 

vehicle activity is a major source of pollutants. However, there are several small industries and 

manufacturing processes located within the two counties. These industries include a brewery, power 

plants, cement plants, mining, electronics and film manufacturing facilities and rock quarries. 

The PM10 monitors in this area are: 

 08 069 0009 Fort Collins-CSU, 251 Edison Drive 

 08 123 0006 Greeley-Hospital, 1516 Hospital Road 

Metropolitan Denver Counties 

This area includes the Front Range Counties of Adams, Arapahoe, Boulder, Broomfield, Clear 

Creek, Douglas, Gilpin, Jefferson and Denver. The population of the area is 2,749,032 (July 2007 

population estimates). This is an increase of 12 percent from the 2000 census. The Denver metropolitan 

area consists of all of Denver County, the western half of Adams and Arapahoe counties, most of Boulder 

and Jefferson counties, the northern portion of Douglas County and none of Clear Creek and Gilpin 

counties. 

The PM10 monitors in this area are: 

 08 001 0006 Commerce City, 7101 Birch Street 

 08 001 3001 Welby, 3174 E. 78th Avenue 

 08 013 0003 Longmont-Municipal, 350 Kimbark Street 

 08 013 0012 Boulder Chamber Building, 2440 Pearl Street 

 08 031 0002 Denver CAMP, 2105 Broadway 

 08 031 0017 Denver Visitor Center, 225 W. Colfax Avenue 

 08 031 0025 Denver Municipal Animal Shelter, 678 S. Jason Street 

 

El Paso, Park & Teller Counties 

This area has a population of 617,864 according to the July 2007 population estimate this is an 

increase of 12.0 percent from the 2000 census. It is a very popular tourist area with rapid urban growth. 

The land usage varies from prairie in eastern El Paso County to very mountainous in Teller and Park 

Counties. Only El Paso County has a large urbanized area, Colorado Springs, with a population of 

394,177 according to the July 2007 estimate. This is an increase of 9.2 percent since the 2000 census. The 

City of Colorado Springs and El Paso County both operate separate monitoring networks that are not 

included as a part of this report. 

The PM10 monitors in this area are: 

 08 041 0017 Colorado College, 130 W. Cache la Poudre Street 

 08 043 0003 Cañon City-City Hall, 128 Main Street 

Colorado Air Monitoring Network Plan – 2009 - 2010 22
Western Counties 

The Western Slope consists of the 21 counties west of the Continental Divide. The population of 

the area is 579,813 (July 2007 population estimate). This is an increase if 14.4 percent over the 2000 

census. However, the population is not evenly distributed among the counties and ranges from Mesa 

County with 140,416 to San Juan County with only 571 according to the July 2007 estimate Grand 

Junction is the largest city on the western slope with a population of 53,662 (July 2007 estimate). This is 

an increase of 27.8 percent from the 2000 census. 

The PM10 monitors in this area are: 

08 003 0001 Alamosa-Adams State College, 208 Edgemont Boulevard 

 08 003 0002 Alamosa Municipal, 425 4th Street 

 08 007 0001 Pagosa Springs, 309 Lewis Street 

 08 029 0004 Delta, 560 Dodge Street 

 08 045 0005 Parachute, 100 E. 2nd Street 

 08 045 0007 Rifle-Henry Building, 144 3rd Street 

 08 051 0004 Crested Butte, 603 6th Street 

 08 051 0007 Mount Crested Butte, 19 Emmons Road 

 08 067 0004 Durango-River City Hall, 1235 Camino del Rio 

 08 077 0017 Grand Junction-Powell, 650 South Avenue 

 08 077 0018 Grand Junction, 6451⁄4 Pitkin Avenue 

 08 077 0019 Clifton, Hwy 141 and D Road 

 08 097 0006 Aspen-Library, 120 Mill Street 

 08 099 0001 Lamar Power Plant, 100 N. 2nd St. 

 08 099 0002 Lamar Municipal, 104 E. Parmenter Street 

 08 101 0012 Pueblo Public Works, 211 D St. 

 08 107 0003 Steamboat Springs, 136 6th Street 

 08 113 0004 Telluride, 333 W. Colorado Avenue 

 08 117 0002 Breckenridge, 501 N. Park Avenue 

Planned Changes in PM10 Monitoring for 2009/2010 

1) The Lamar Power Plant monitor will be considered for removal and replacement in 2009 due 

to conversion of the plant to coal burning. 

Colorado Air Monitoring Network Plan – 2009 - 2010 23

2) The Pueblo site will be relocated in 2009 due to the construction of a tall building next to the 

current building. 
PM2.5 Monitoring 

Larimer and Weld Counties 

Larimer and Weld counties have a population of 532,759 (July 2007 population estimates), an 

increase of 23.2 percent since the 2000 Census. The two major urban centers are Fort Collins in Larimer 

County and Greeley in Weld County. Larimer County has irrigated farmland in the eastern half while the 

western half is mountainous. Weld County is predominantly grassland and irrigated farmland. Motor 

vehicle activity is a major source of pollutants. However, there are several small industries and 

manufacturing processes located within the two counties. These industries include a brewery, power 

plants, cement plants, mining, electronics and film manufacturing facilities and rock quarries. The 

following PM2.5 sites with manual method FRM sites are in the APCD network as of December 31, 2008, 

and are suitable for comparisons to the annual PM2.5 NAAQS. 

The PM2.5 monitors (with POC codes) in this area are: 

08 069 0009-1 Fort Collins-CSU, 251 Edison Drive 

08 123 0006-1 Greeley-Hospital, 1516 Hospital Road 

08 123 0008-1 Platteville, 1004 Main Street 

Metropolitan Denver Counties 

This area includes the Front Range Counties of Adams, Arapahoe, Boulder, Broomfield, Clear 

Creek, Douglas, Gilpin, Jefferson and Denver. The population of the area is 2,749,032 (July 2007 

population estimates). This is an increase of 12 percent from the 2000 census. The Denver metropolitan 

area consists of all of Denver County, the western half of Adams and Arapahoe counties, most of Boulder 

and Jefferson counties, the northern portion of Douglas County and none of Clear Creek and Gilpin 

counties. The following PM2.5 sites with manual method FRM sites are in the APCD network as of 

December 31, 2008, and are suitable for comparisons to the annual PM2.5 NAAQS. 

The PM2.5 monitors (with POC codes) in this area are: 

08 001 0006-1 Commerce City, 7101 Birch Street 

08 005 0005-1 Arapahoe Community College, 6190 S. Santa Fe Boulevard 

08 013 0003-1 Longmont-Municipal, 350 Kimbark Street 

08 013 0012-1 Boulder/Chamber Building, 2440 Pearl Street 

– Middle scale site but determined to be representative of neighborhood scale with 

several contiguous middle scale sites in that area of Boulder. EPA approved. 

08 031 0002-1 Denver CAMP, 2105 Broadway 

– micro scale but determined to be representative of neighborhood scale with several 

contiguous micro scale sites in downtown Denver. EPA approved. 

 08 031 0023-1 Denver Swansea, 4650 Columbine Street 

08 031 0025-1 Denver Animal Shelter, 678 S. Jason Street 

08 035 0004-1 Chatfield Reservoir, 11500 N. Roxborough Park Road 

 

El Paso, Park, Pueblo, Elbert & Teller Counties 

Colorado Air Monitoring Network Plan – 2009 - 2010 24

This area has a population of 807,732 according to the July 2007 population estimate this is an 

increase of 12.0 percent from the 2000 census. It is a very popular tourist area with rapid urban growth. 

The land usage varies from open prairies in eastern El Paso County to very mountainous in Teller and 

Park Counties. Only El Paso County has a large urbanized area, Colorado Springs, with a population of 

394,177 according to the July 2007 estimate. This is an increase of 9.2 percent since the 2000 census. The 

City of Colorado Springs and El Paso County both operate separate monitoring networks that are not 

included as a part of this report. The following PM2.5 sites with manual method FRM sites are in the 

APCD network as of December 31, 2008, and are suitable for comparisons to the annual PM2.5 NAAQS. 
The PM2.5 monitors (with POC codes) in this area are: 

 08 039 0001-1 Elbert County, 24950 Ben Kelly Road 

08 041 0017-1 Colorado College, 130 W. Cache la Poudre Street 

08 101 0012-1 Pueblo, 211 E. D Street 

Western Counties 

The Western Slope consists of the 21 counties west of the Continental Divide. The population of 

the area is 579,813 (July 2007 population estimate). This is an increase if 14.4 percent over the 2000 

census. However, the population is not evenly distributed among the counties and ranges from Mesa 

County with 140,416 to San Juan County with only 571 according to the July 2007 estimate. Short-term 

special purpose monitoring for carbon monoxide has been done in Summit County at Vail and near the oil 

shale projects of Rio Blanco County. Grand Junction is the largest city on the western slope with a 

population of 53,662 (July 2007 estimate). This is an increase of 27.8 percent from the 2000 census. The 

following PM2.5 sites with manual method FRM sites are in the APCD network as of December 31, 2008, 

and are suitable for comparisons to the annual PM2.5 NAAQS. 

The PM2.5 monitors (with POC codes) in this area are: 

08 077 0017-1 Grand Junction-Powell, 650 South Avenue 

PM2.5 Sites not intended for NAAQS Comparison 

The following sites and POC codes are not intended for comparison with the NAAQS: 

08 001 0006-3 Commerce City, 7101 Birch Street 

08 013 0003-3 Longmont-Municipal, 350 Kimbark Street 

08 013 1001-3 Boulder CU/Athens, 2440 Pearl Street 

08 031 0002-3 Denver-CAMP, 2105 Broadway 

08 031 0013-3 Denver NJH-E, 14th Avenue and Albion Street 

08 031 0025-3 Denver Municipal Animal Shelter, 678 S. Jason Street 

08 035 0004-3 Chatfield Reservoir, 11500 N. Roxborough Park Road 

08 041 0017-3 Colorado College, 130 W. Cache la Poudre 

08 045 0007-1 Rifle, Henry Building, 144 N. 3rd Street 

08 069 0009-3 Fort Collins-CSU, 251 Edison Drive 

08 077 0017-3 Grand Junction-Powell, 650 South Avenue 

08 083 0006-1 Cortez, 106 W. North Street 

08 123 0006-3 Greeley-Hospital, 1516 Hospital Road 

Community Monitoring Zones 

 Community monitoring zones are an additional method of defining an area for comparison with 

the PM2.5 NAAQS where two or more monitors are averaged together for comparison with the standard. 

Currently, the APCD does not have any areas where this technique is used. 

Colorado Air Monitoring Network Plan – 2009 - 2010 25

The definition of community monitoring zone (CMZ) in 40 CFR Part 58.1 is as follows: 

“Community monitoring zone (CMZ) means an optional averaging area with established, well defined 

boundaries, such as county or census block, within an MPA that has relatively uniform concentrations of 

annual PM2.5 as defined by appendix N of part 50 of this chapter. Two or more community oriented 

SLAMS monitors within a CMZ that meet certain requirements as set forth in appendix N of part 50 of 

this chapter may be averaged for making comparisons to the annual PM2.5 NAAQS.” The CMZ is an 

optional technique that averages the PM2.5 24-hour concentrations from two or more monitors located in 

the same community. 
If the PM2.5 monitoring network is changed by the creation/change of a CMZ or changing the 

location of a violating monitor, then the APCD will ask EPA Region VIII for approval via the current 

network modification process, and then notify the appropriate governments of affected communities. The 

APCD will also provide the proposed changes to the affected communities and concerned citizens on our 

web site. A public comment period will be open for thirty (30) days prior to the APCD selecting a new 

site. Many times the APCD has no control over a site closure. For example, a site is closed due to the 

planned demolition of the building that hosts the monitor. In such cases a new site must be found. The 

PM2.5 instruments may be moved to a temporary site and monitoring resumed. However, the final site 

selection will go through the public vetting process to locate the best possible site. 

Planned Changes in PM2.5 Monitoring for 2009/2010 

1. The Pueblo site will be relocated in 2009 due to the construction of a tall building next to the 

current building. 

2. Addition of a PM10/2.5 TEOM in Fort Collins in 2009. 

3. Possible relocation of Boulder CU/Athens TEOM site due to new construction near the site. 

4. Add URS carbon sampler for PM2.5 chemical speciation at the Platteville and Grand Junction/ 

Powell sites in 2009. 

5. Plan to move PM2.5 chemical speciation sampler from the Grand Junction Powell to NCore 

site at DMAS by December 31, 2009. 

Total Suspended Particulates and Lead Monitoring 

In December 2006 Total Suspended Particulate (TSP) monitoring by the Air Pollution Control 

Division was reduced from six monitors to a single monitor at the Denver Municipal Animal Shelter. TSP 

is monitored only as a first step in ambient lead analysis. In the past ten years the maximum quarter lead 

concentration has generally been less than a tenth of the standard. In addition, Colorado has not recorded 

an exceedance of the lead standard since the first quarter of 1980. 

The Division reviewed its stationary sources database for all point sources that emit lead in 

Colorado. There were 32 lead sources identified in a database retrieval conducted in November, 2008. 

None of the sources emit greater than one ton per year (TPY) of total lead, which includes elemental lead 

and all lead compounds. Thus, no lead monitors are required at any point source facility in Colorado. 

The U.S. EPA calculated emissions for lead at general aviation airports due to piston engine 

aircraft, which continue to use leaded aviation fuel. According to EPA, Centennial Airport has the second 

highest lead emissions of any airport in the country at 1.18 TPY. Since, this emissions estimate exceeds 

the threshold for lead; the Division will locate a lead sampling site at or near the Centennial Airport. This 

monitoring site must be installed by Jan. 1, 2010. 

Metropolitan Denver Counties 

This area includes the Front Range Counties of Adams, Arapahoe, Boulder, Broomfield, Clear 

Creek, Douglas, Gilpin, Jefferson and Denver. The population of the area is 2,749,032 (July 2007 

population estimates). This is an increase of 12 percent from the 2000 census. The Denver metropolitan 

area consists of all of Denver County, the western half of Adams and Arapahoe counties, most of Boulder 

and Jefferson counties, the northern portion of Douglas County and none of Clear Creek and Gilpin 

counties. 

The TSP/Lead monitor in this area is: 

08 031 0025 Denver Municipal Animal Shelter, 678 S. Jason Street 

– This site served as the CFR required regional lead site until the new lead standard was 

promulgated in December 2008. 

Colorado Air Monitoring Network Plan – 2009 - 2010 26
New Lead NAAQS 

 In November 2008, a new TSP lead NAAQS was promulgated at a level of 0.15 micrograms per 

cubic meter based on a 3-month rolling average. This new standard set forth new requirements for 

required monitoring sites to include: 

1. At least one site located around sources with lead emissions greater than one TPY. Sourceoriented monitoring must commence by January 1, 2010. 

2. At least one site in CBSAs with populations greater than 500,000. Population-oriented 

monitoring must commence by January 1, 2011. 

For Colorado, only one source has been identified with emissions greater than one TPY. It is 

Centennial Airport. The ideal goal is have source-oriented monitors located in ambient air at the predicted 

maximum lead concentration area. Typically, the location of maximum lead concentration for airports 

will be downwind of the take off strip near the “blast fence.” Discussions will be undertaken with 

Centennial Airport to meet this requirement as close as possible and a monitor will be installed by the end 

of 2009. One other source, CENC Golden Energy, has been identified in the NEI as possibly having over 

one TPY of lead emissions. However, permit and actual emission levels have shown this facility does not 

exceed this threshold. 

In Colorado, there are two CBSAs that are over populations of 500,000. They are Denver and 

Colorado Springs. The Denver area is already monitored with the Denver Municipal Animal Shelter (08 

031 0025) site. One additional site will be installed in Colorado Springs by the end of 2010 to meet the 

monitoring requirements. At this time, the monitor will most likely be placed at the existing Colorado 

College (08 041 0017) site unless modeling or other guidance indicates otherwise. 

Planned Changes in TSP and Lead Monitoring for 2009/2010 

1. In 2009 the Division will establish a source-oriented TSP/Lead monitor at Centennial Airport. 

This site is needed due to the changes in the lead monitoring regulations that require sourceoriented monitoring at facilities with emissions of more than one ton per year. 

2. A new population oriented led monitor will be established in Colorado Springs in 2010. This site 

is in response to changes in new minimum population requirements for lead monitoring. 

Quality Assurance Accuracy Audits for Particulate Monitors 

The audit checks performed on the particulate monitors consist of calibrated flow checks. The 

following table shows the number of these audits conducted on the particulate samplers/analyzers for 

2008. 

Colorado Air Monitoring Network Plan – 2009 - 2010 27
Table 12 - Accuracy Audits for Particulates in 2008 

Site / Station Name 

PM2.5

PEP 

PM2.5 

FRM/FEM 

PM10 

Low-Vol 

PM10 

High-Vol TSP TEOM(2.5) TEOM(10)

Commerce City 4 4 3 

Commerce City (collocated) 4 

Welby 4 4 

Chatfield Reservoir 4 4 

Alamosa - ASC 16 

Alamosa - Municipal Bldg 16 

Arapahoe Community College 4 

Pagosa Springs. Middle School 16 

Longmont - Municipal 4 4 4 

Boulder Chamber of Commerce 4 4 

Boulder - CU/Athens 4 

Delta 8 

Denver - CAMP 4 4 3 3 

Denver - CAMP (collocated) 4 4 

Denver Municipal Animal Shelter 

(primary) 4 4 4 4 4 

Denver Municipal Animal Shelter 

(collocated) 4 4 

Denver - Swansea 3 

Denver Visitor Center 16 

Denver - NJH 3 

Elbert 4 

Colorado Springs - RBD 1 1 

Co. Springs - RBD (collocated) 1 

Colorado College 4 4 3 

Cañon City – City Hall 4

Parachute 6 

Rifle 8 

Crested Butte 8 

Mt. Crested Butte 16 

Durango River City Hall 8 

Ft. Collins - CSU 3 4 8 

Grand Junction - Powell 3 4 4 3 

Grand Junction - Powell (collocated) 4 

Clifton 8 

Aspen Library 8 

Lamar Power Plant 16 

Lamar - Municipal 16 

Pueblo Public Works 4 8 

Steamboat Springs 12 

Telluride 8 

Breckenridge 16 

Greeley - Hospital 4 8 4 

Platteville 3 

Total Particulate Audits 6 67 20 256 8 35 11 

Colorado Air Monitoring Network Plan – 2009 - 2010 28
Quality Assurance Precision Checks for Particulate Monitors 

 The precision checks that are made on particulate monitors consist of samplers that operate sideby-side on the same operating schedule. The samples are then compared to ensure that the data are within 

federal limits. 

Table 13 - Precision Checks for Particulates in 2008

Colorado Air Monitoring Network Plan – 2009 - 2010 29

Site 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter

 

TSP 

Denver Municipal Animal Shelter 15 15 15 14 

 

LEAD 

Denver Municipal Animal Shelter 15 15 15 10 

 

PM10 High-Volume 

Denver - CAMP

Denver Municipal Animal Shelter 15 14 15 14 

Colorado Springs - RBD 16 

Crested Butte 15 

PM10 Low-Volume 

Grand Junction - Powell 15 15 15 12 

 

PM2.5 FEM 

Commerce City 15 15 15 15 

Denver - CAMP 16 15 15 15 

Grand Junction - Powell

PM2.5 Continuous 

Commerce City 3 6 7 5 

Longmont - Municipal 5 2 4 5 

Boulder - CU/Athens 3 3 4 6 

Denver - CAMP 5 4 6 6 

Denver - NJH 6 6 6 5 

Chatfield 6 6 6 5 

Denver Municipal Animal Shelter 3 6 7 6 

Colorado College 4 6 7 

Grand Junction - Powell 5 5 4 3 

Greeley - Hospital 6 6 5 6 

 

PM10 Continuous TEOM 

Welby 8 7 7 6 

Denver - CAMP 6 5 7 7 

Denver Municipal Animal Shelter 4 6 8 6 

 

PM10 Continuous Beta 

Grand Junction - Pitkin 5 5 4 0 
Appendix A - Carbon Monoxide Site Descriptions 

Welby, 3174 E. 78th Avenue (08 001 3001) 

Located 8 miles north-northeast of the Denver Central Business District (CBD) on the bank of the 

South Platte River, this site is ideally located to measure nighttime drainage of the air mass from the 

Denver metropolitan area and the thermally driven, daytime upriver flows. The monitoring shows that 

high carbon monoxide levels are associated with winds from the south-southwest. While this is the 

direction of five of the six major sources in the area, it is also the direction of the primary drainage winds 

along the South Platte River. 

Carbon monoxide monitoring began in 1973 and continued through the spring of 1980. 

Monitoring was stopped from the spring of 1980 until October 1986 when it began again as a special 

study. Welby has not recorded an exceedance of either the 1-hour or 8-hour carbon monoxide standard 

since January 1988. In the last few years its primary value has been as an indicator of changes in the air 

quality index (AQI). 

Longmont, 440 Main Street (08 013 0009) 

The town of Longmont is a growing, medium sized, Front Range community. Denver/Boulder 

Metro-area and Fort Collins. Longmont is both suburban and rural in nature. There are no major carbon 

monoxide sources within 12 miles of the monitor. 

In January and February of 1988 and again in the winter of 1988/89 the APCD conducted a study 

at a site near 11th Avenue and Main Street, a few blocks north of the downtown area. Because two 

exceedances of the standard were recorded during the study, the Division felt that a permanent carbon 

monoxide site should be established closer to the downtown area. These exceedances resulted in 

Longmont being designated as a carbon monoxide nonattainment area and required a SIP for carbon 

monoxide be developed showing attainment by December 31, 1995. The Air Quality Control Commission 

accepted the Longmont SIP on June 16, 1995. In 1999, Longmont was redesignated as an attainment area. 

Longmont has contended that its carbon monoxide problems are generally the result of transport from the 

Denver metropolitan area north to the Longmont area. The review of the time series plots for Longmont, 

Denver CAMP, Greeley and Boulder show that the carbon monoxide maximum at all four locations 

generally coincide. In addition these peaks are bimodal at 7 to 9 A.M. and 4 to 6 P.M. at all four 

locations. This pattern is associated with locally generated emissions from traffic, not transport from 

another area. The carbon monoxide emissions inventories developed for the SIP show that 78 percent of 

the carbon monoxide comes from on-road mobile sources. These findings are consistent with the 

observed distribution of the data. 

Carbon monoxide monitoring is expected to continue for the next several years at the current 

location since the monitoring is a part of the maintenance plan for Longmont. 

Denver CAMP, 2105 Broadway (08 031 0002) 

The Denver CAMP site is located in the north-central part of the Denver CBD. Denver is the 

largest city in Colorado. Carbon monoxide monitoring began in February 1965 as a part of the Federal 

Continuous Air Monitoring Project. It was established as a maximum concentration, population-oriented 

monitor. The CAMP site measures the exposure of the people who work or reside in the CBD. Its location 

in a high traffic street canyon causes this site to record most of the high pollution episodes in the metro 

area. The street canyon effect at CAMP results in variable wind directions for high carbon monoxide 

levels and as a result wind direction is less relevant to high concentrations than wind speed. Wind speeds 

less than 1 mph, especially up-valley, combined with temperature inversions trap the pollution in the area. 

Colorado Air Monitoring Network Plan – 2009 - 2010 30

Historically the CAMP monitor has recorded some of the highest carbon monoxide levels in the 

state. It has not recorded an 8-hour concentration over the standard since 1995. The concentrations have 
continued their steady decline to the point that in 2008 they are now less than one third the level of the 

standard. 

Denver Firehouse #6, 1300 Blake Street (08 031 0019) 

The Denver Firehouse #6 is located on the block between Auraria Parkway and Blake Street 

where they intersect with Speer Boulevard. This is one of the busiest intersections in downtown Denver 

and computer modeling indicated that it would have high levels of carbon monoxide. 

In the winter of 1995 the monitor was converted from a special purpose monitor to a SLAMS 

monitor. In 1999 the Firehouse monitor recorded the last exceedance of the 8-hour CO standard in the 

Denver Metro area. The levels have continued their decline and in 2008 the maximum 8-hour 

concentration was 2.4 ppm. 

Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

 The Denver Municipal Animal Shelter (DMAS) site was established as a replacement for the 

Denver Gates particulate monitor that was located at 1050 S. Broadway about one half mile southsoutheast and on the other side of the South Platte River and I-25 South. The DMAS location represents 

the core area of the South Platte drainage in Denver. It has a good mixture of light industrial, residential 

areas and is strongly affected by the mobile sources along I-25 as well as South Santa Fe Drive. The 

openness of the area also permits the meteorological data to be representative of the larger core Denver 

area. Finally the site is on City owned property and will presumably be available for long-term trend 

analysis. When fully developed the site will be established as the NCore site for the Denver Metropolitan 

area and will include a trace/precursor-level carbon monoxide analyzer. 

Colorado Springs Hwy-24, 690 W. Highway 24 (08 041 0015) 

The 690 W. Highway 24 site is located just to the west of I-25 and just to the east of the 

intersection of U.S. Highway 24 and 8th Street, approximately 0.8 miles to the west of the Colorado 

Springs CBD. Commencing operation in November 1998, this site is a replacement for the Tejon Street 

(08 041 0004) carbon monoxide monitor. The site is located in the Fountain Creek drainage and is in one 

of the busiest traffic areas of Colorado Springs. Additionally, traffic is prone to back-up along Highway 

24 due to a traffic light at 8th Street. Thus, this site is well suited to monitor maximum concentrations of 

carbon monoxide in the area both from automotive sources and also from nearby industry which includes 

a power plant. It also provides a micro-scale setting for the Colorado Springs area, which has not been 

possible in the past. 

Fort Collins- Mason, 708 S. Mason Street (08 069 1004) 

Fort Collins does not have the population to require a carbon monoxide monitor under Federal 

regulation. However, it is one of the largest cities along the Front Range and was declared in 

nonattainment for carbon monoxide in the mid-1970s after exceeding the 8-hour standard in both 1974 

and 1975. The current level of monitoring is in part a function of the resulting carbon monoxide SIP for 

the area. 

The 708 S. Mason Street site began operation in December 1980 and is located one block west of 

College Avenue in the Central Business District. The 1-hour carbon monoxide standard of 35 ppm as a 1-

hour average has only been exceeded on December 1, 1983, at 4:00 P.M. and again at 5:00 P.M. The 

values reported were 43.9 ppm and 43.2 ppm respectively. The 8-hour standard of 9 ppm, as an 8-hour 

average, was exceeded one or more times a year from 1980 through 1989. The last exceedances were in 

1991 on January 31 and December 6 when values of 9.8 ppm and 10.0 ppm respectively were recorded. 

Grand Junction - Pitkin, 6451⁄4 Pitkin Avenue (08 077 0018) 

Colorado Air Monitoring Network Plan – 2009 - 2010 31

The Grand Junction-Pitkin monitor began operation in January 2004. This monitor replaced the 

monitor at the Stocker Stadium. The Stocker Stadium location had become less than ideal with the growth 
of the trees surrounding the park and the Division felt that a location nearer to the CBD would provide a 

better representation of carbon monoxide concentration values for the city. The carbon monoxide 

concentrations at the Stocker Stadium site had been declining from an 8-hour maximum in 1991 of 7.8 

ppm to a 3.3 ppm in 2003. The Powell monitor has shown a continuing decline in values to a 1.8 ppm in 

2007. These levels are approaching the detection limits of the carbon monoxide monitor. 

Greeley West Annex Bldg, 905 10th Avenue (08 123 0010)

Greeley does not have the population to require a carbon monoxide monitor under Federal 

regulation. However, it is one of the larger cities along the Front Range and was declared in 

nonattainment for carbon monoxide in the late-1970s after exceeding the 8-hour standard in 1976 and 

1977. The first Greeley monitor operated from December 1976 to December 1980. It was located at 15th

Street and 16th Avenue and exceeded the 8-hour standard numerous times from 1976 through 1980. 

The 811 15th Street location began operation in November 1981 and was discontinued in 2002. 

The current monitor is located in the Weld County Health Department Annex. This location is in the 

Greeley Central Business District. The levels recorded at this site are comparable but slightly lower than 

those at the former 811 15th Street site, about a quarter of the 8-hour standard. 

Colorado Air Monitoring Network Plan – 2009 - 2010 32
Appendix B - Ozone Site Descriptions 

Welby, 3174 E. 78th Avenue (08 001 3001) 

The Welby ozone site began operation in July 1973. In 1974, Welby recorded a 1-hour 

concentration of 0.375 ppm. This is the highest level of ozone ever reported in the State. Since then it has 

experienced a declining trend of ozone and now records some of the lowest levels in the area. It is unclear 

if declining levels are due to controls on precursors, increases in nitric oxide levels, high levels of 

precursors present in the area of the site, or a shift in the path of the ozone “cloud.” Its location in the up 

and down river drainage path of the Denver air mass that has been “cooking” gives either a warning of the 

events to come or the results of the day's exposure. The site serves as a good drainage location but it may 

be a target for deletion or relocation farther down the South Platte River valley from Denver. 

The Welby monitor has not recorded an exceedance of the old 1-hour standard since 1998. It 

would not have recorded an exceedance of the new 8-hour standard since 1998. However, the trend in the 

3-year average of the 4th maximum 8-hour average has been increasing since 2002. The site is still not 

expected to exceed the new standard in the near future though. 

Highland Reservoir, 8100 S. University Boulevard (08 005 0002) 

The Highlands site began operation in 1978. It was intended to be a background location. 

However, with urban growth and the construction of C-470, it has become a long-term trend site that 

monitors changes in the air quality of the area. It is currently believed to be near the southern edge of the 

ozone “cloud,” although it may not be in the area of maximum concentrations. The Highlands site would 

have exceeded the new standard eight of the last ten years. 

Aurora – East, 36001 Quincy Ave. (08 005 0006) 

 The Aurora East site began operation in June 2009. It is intended to act as a background site and 

an aid in the determination of the easternmost extent of the ozone “cloud” in the metro area. It is located 

along the eastern edge of the former Lowry bombing range, on a flat, grassy plains area. This site is 

currently outside of the rapid urban growth area taking place around Aurora Reservoir. There are 

currently plans to begin developing the Lowry area in the near future, however, which would shift the 

focus of this site from being a background site to an urban corridor site. 

Boulder, 14051⁄2 S. Foothills Parkway (08 013 0011) 

The city of Boulder is located about 30 miles to the northwest of Denver. The Boulder Foothills, 

South Boulder Creek site was established as a special purpose ozone monitor as a part of the “Summer 

1993 Denver Ozone Study.” During that summer a 1-hour level of 0.128 ppm was recorded on July 2, 

1993. In 1994 the monitor was converted from an SPM to a seasonal SLAMS and in 1995 to a year-round 

ozone monitor when the instruments were moved into a new shelter. The South Boulder Creek monitor 

has not recorded an exceedance of the 1-hour NAAQS since the summer of 1993. 

Although the Foothills monitor had not exceeded the previous standard of 0.085 ppm as an 8-hour 

average. It would have exceeded the new standard of 0.075 ppm as an 8-hour average five of the past six 

years. 

Denver - Carriage, 2325 W. Irving Street (08 031 0014) 

Carriage is located 2.5 miles west of the CBD. The site represents an ideal neighborhood 

exposure setting due to its unique location in an old carriage lot in the center of the block surrounded by 

houses. The Carriage ozone site began operation in 1981. It represents a good neighborhood site for ozone 

exposure since it is isolated enough to be unaffected by local traffic. Ozone levels at this site have not 

exceeded the old 1-hour NAAQS since 1987. The Denver Carriage monitor would have exceeded the new 

standard only once in the past ten years. 

Colorado Air Monitoring Network Plan – 2009 - 2010 33
Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

 The Denver Municipal Animal Shelter (DMAS) was established as a replacement for the Denver 

Gates particulate monitor that was located at 1050 S. Broadway about one half mile south-southeast and 

on the other side of the South Platte River and I-25 South. The DMAS location represents the core area of 

the South Platte drainage in Denver. It has a good mixture of light industrial, residential areas and is 

strongly affected by the mobile sources along I-25 as well as South Santa Fe Drive. The openness of the 

area also permits the meteorological data to be representative of the larger core Denver area. Finally the 

site is on City owned property and will presumably be available for long-term trend analysis. When fully 

developed the site will be established as the NCore site for the Denver Metropolitan area. 

Chatfield Reservoir, 11500 N. Roxborough Park Road (08 035 0004) 

The Chatfield Reservoir location was established as the result of the 1993 Summer Ozone Study. 

The site is located on the south side of Chatfield Reservoir at the park offices. This location was selected 

over the Corps of Engineers Visitor Center across the reservoir because it was more removed from the 

influence of traffic along C-470. Located in the South Platte River drainage, this location is well suited 

for monitoring southwesterly ozone formation in the Denver metro area. The Chatfield monitor would 

have exceeded the new standard each of the past four years and the trend of the 3-year averages is 

increasing. 

Colorado Springs, USAFA Road 640 (08 041 0013) 

The United States Air Force Academy site was installed as a replacement maximum 

concentration ozone monitor for the Chestnut Street (08 041 0012) site. Modeling in the Colorado Springs 

area indicates that high ozone concentrations should generally be found along either the Monument Creek 

drainage to the north of the Colorado Springs CBD or to a lesser extent along the Fountain Creek drainage 

to the west of the CBD. The decision was made to locate this site near the Monument Creek drainage, 

approximately 9 miles north of the CBD. This location is near the south entrance of the Academy but 

away from any roads. 

The Academy monitor did record an exceedance of the old 1-hour standard in 2003 but it would 

not have recorded any exceedances of the new 8-hour standard. However the trend in values over the past 

ten years is increasing. 

Manitou Springs, 101 Banks Place (08 041 0016) 

Manitou Springs is a located 4 miles west of Colorado Springs. It was established because of 

concern that the “ozone cloud” was traveling farther up the canyon and the current monitoring network 

was not adequate. The Manitou Springs monitor began operations in April 2004. It is located in the 

foothills above Colorado Springs in the back of the maintenance area. In its four seasons of operation it 

has not recorded any levels greater than the new standard. The trend in 8-hour concentrations is 

increasing. 

Rifle - Health, 195 14th Ave. (08 045 0012) 

 The Rifle Health site is located at the Garfield County Health Department building. The site is 

1km to the north of the downtown area and next to the Garfield County fairgrounds. The site is uphill 

from the downtown area. A small residential area is to the north and a commercial area to the east. This 

site was established to measure ozone in Rifle, which is the largest population center in the oil and gas 

impacted area of the Grand Valley. Monitoring commenced in June 2008. 

Arvada, 9101 57th Avenue (08 059 0002) 

Colorado Air Monitoring Network Plan – 2009 - 2010 34

The city of Arvada is located 15 miles west-northwest of the Denver CBD. The Arvada site began 

operation before 1973. It is located to the northwest of the Denver CBD near the western end of the 

diurnal midday wind flow of the ozone “cloud.” As a result, when conditions are proper for daylong 
ozone production, this site has received some of the highest levels in the city. In the early and mid 1970s, 

these wind patterns caused Arvada to have the most violations in the metro area. The Arvada monitor 

would have exceeded the new standard six of the past ten years and the years that it would not have 

exceeded the standard it was just below the level of the standard. 

Welch, 12400 W. Highway 285 (08 059 0005) 

The Division conducted a short-term ozone study on the grounds of Chatfield High School from 

June 14, 1989 until September 28, 1989. The Chatfield location was chosen because it sits on a ridge 

southwest of the Denver CBD. Wind pattern studies showed a potential for elevated ozone levels in the 

area on mid to late afternoon summer days. There were no exceedances of the NAAQS recorded at the 

Chatfield site but the levels were frequently higher than those recorded at the other monitoring sites south 

of the metro area. 

One finding of the study was the need for a new, permanent site further north of the Chatfield 

High School location. As with most Denver locations, the predominant wind pattern is north/south. The 

southern flow occurs during the upslope, daytime warming period. The northern flow occurs during late 

afternoon and nighttime when drainage is caused by cooling and settling. The major drainages of Bear 

Creek and Turkey Creek were selected as target downwind transport corridors. These are the first major 

topographical features north of the Chatfield site. A point midway between the valley floor (Englewood 

site) and the foothill’s hogback ridge was modeled to be the best estimate of the maximum downwind 

daytime transport area. These criteria were used to evaluate available locations. The Welch site best met 

these conditions. This site is located off State Highway 285 between Kipling Street and C-470. 

The Welch monitor would not have exceeded the new standard in the past ten years. However, 

since 2002 the trend in values is increasing and in 2008 the 3-year average was above the level of the 

standard. 

Rocky Flats - N, 16600 W. Highway 128 (08 059 0006) 

The Rocky Flats - N site is located north-north east of the plant on the south side of Colorado 

Highway 128, approximately 11⁄4 miles to the west of Indiana Street. The site began operation in June 

1992 as a part of the first phase of the APCD’s monitoring effort around the Rocky Flats Environmental 

Technology Site. 

Ozone monitoring began as a part of the “Summer 1993 Ozone Study”. The monitor recorded 

some of the highest ozone levels of any of the sites during that study. Therefore, it was included as a 

regular part of the APCD ozone-monitoring network. The Rocky Flats – N monitor would have exceeded 

the new standard each of the last ten years and thirteen out of the last fifteen years. 

NREL Solar Radiation Research Laboratory, 2054 Quaker Street (08 059 0011) 

The National Renewable Energy Laboratory (NREL) site is located on the south rim of South 

Table Mountain, near Golden and was part of the 1993 Summer Ozone Study. Based on the elevated 

concentrations found at this location, it was made a permanent monitoring site in 1994. This site typically 

records some of the higher 8-hour ozone concentrations in the Denver area. It would have exceeded the 

new standard each of the past thirteen years it has been in operation. 

Aspen Park, 26137 Conifer Road (08 059 0013) 

Colorado Air Monitoring Network Plan – 2009 - 2010 35

 The Aspen Park site began operation in May 2009. It is intended to verify/refute model 

predictions of above normal ozone levels. In addition, passive ozone monitors used in the area in a 2007 

study indicated the possibility of larger than normal ozone levels. The monitor is located in an urban 

setting at a Park N Ride facility off of Highway 285, at an elevation of just over 8,100 feet. Because the 

site is nearly 3,000 feet higher than the average metro area elevation, it should see ozone levels that are 

larger than those seen in the metro area, as ozone concentrations increase with increasing elevation. 
Whether or not the increased concentrations will be a health concern will be determined with the data 

gathered from this monitor. 

Fort Collins - West, 3416 W. La Porte Avenue (08 069 0011) 

The Fort Collins-West monitor began operation in May of 2006. The location was established 

based on modeling and to satisfy permit conditions for a major source in Fort Collins area. The levels 

recorded for the first season of operation have shown consistently higher concentrations than the 708 S. 

Mason Street monitor. For 2008 the 8-hour average, 4th maximum was 0.085 ppm. The 4th maximum, 8-

hour average at the Mason Street monitor was 0.069 ppm for the same period. 

Fort Collins - Mason, 708 S. Mason Street (08 069 1004) 

The Fort Collins ozone site has been in operation since 1981 and has recorded only one 

exceedance of the former 1-hour standard since it began operation. It has only recorded four 

concentrations greater than the level of the 8-hour standard and has not ever had a third or fourth 

maximum concentration at or above the level of the 8-hour standard. Monitoring in this area will likely 

continue so that changes in the Fort Collins area may be examined, although violations are not expected. 

At this time there have not been any changes in the area that would require adjustment in the current 

monitoring level. Due to the size of the community, elevated ozone readings in Fort Collins probably 

result from second day transport/reactions from the Denver area. 

Rist Canyon, 11838 Rist Canyon Road, (08 069 0011) 

 The Rist Canyon site began operation in May 2009. The monitor is located within the Rist 

Canyon Volunteer Fire Department Station Number 1, in the foothills west of Fort Collins. The monitor is 

at an elevation of 6,750 feet, which is roughly 1,600 feet above the Fort Collins – West monitor. Model 

predictions have indicated the development of larger than normal ozone levels in this area. The site is 

intended to verify/refute the model prediction. 

Palisade Water Treatment, Rapid Creek Rd (08 077 0020) 

 The Palisade site is located at the Palisade Water Treatment Plant. The site is 4km to the eastnortheast of downtown Palisade, just into the De Beque Canyon area. The site is remote from any 

significant population and was established to measure maximum concentrations of ozone that may result 

from summertime up-flow conditions into a topographical trap. Monitoring commenced in May 2008. 

Cortez, 106 W. North St. (08 083 0006) 

The Cortez site is located in downtown Cortez at the Montezuma County Health Department 

building. Cortez is the largest population center in Montezuma County in the southwest corner of 

Colorado. This site was established to address community concerns of possible high ozone from oil and 

gas and power plant sources in the area. Many of these sources are in New Mexico. Monitoring 

commenced in May 2008. 

Greeley - Weld County Tower, 3101 35th Avenue (08 123 0009) 

The Weld County Tower monitor began operation in June 2002. The site was established after the 

811 15th Street building was sold and was scheduled for demolition. The Weld County Tower site has 

generally recorded levels greater than the old site and would have exceeded the new standard each year 

since it began operation in 2002. 

Colorado Air Monitoring Network Plan – 2009 - 2010 36
Appendix C - Nitrogen Dioxide Site Descriptions 

Welby, 3174 E. 78th Avenue (08 001 3001) 

 The Welby nitrogen dioxide site began operation in July 1976. Its location in the up and down 

river drainage path of the Denver air mass that has been “cooking” gives either a warning of the events to 

come or the results of the day's exposure. The site serves as a good drainage location but it may be a 

target for deletion or relocation farther down the South Platte River valley from Denver. 

Denver CAMP, 2105 Broadway (08 031 0002) 

The City and County of Denver is located approximately 30 miles east of the foothills of the 

Rocky Mountains. Denver sits in a basin and the terrain of the city is characterized as gently rolling hills 

with the Platte River running from southwest to northeast just west of the downtown area. 

The site represents a location typical of most of the downtown Denver area. The Division has 

shown that the downtown Denver area and the fringe area surrounding the downtown area is 

homogeneous and indicates that the CAMP station is representative of a wider area. Thus, the CAMP 

nitrogen dioxide site is representative of a neighborhood scale area. 

Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

 The Denver Municipal Animal Shelter (DMAS) was established as a replacement for the Denver 

Gates particulate monitor that was located at 1050 S. Broadway about one half mile south-southeast and 

on the other side of the South Platte River and I-25 South. The DMAS location represents the core area of 

the South Platte drainage in Denver. It has a good mixture of light industrial, residential areas and is 

strongly affected by the mobile sources along I-25 as well as South Santa Fe Drive. The openness of the 

area also permits the meteorological data to be representative of the larger core Denver area. Finally the 

site is on City owned property and will presumably be available for long-term trend analysis. When fully 

developed the site will be established as the NCore site for the Denver Metropolitan area. 

Colorado Air Monitoring Network Plan – 2009 - 2010 37
Appendix D - Sulfur Dioxide Site Descriptions 

Welby, 3174 E. 78th Avenue (08 001 3001) 

The Welby sulfur dioxide site began operation in July 1975. Its location in the up and down river 

drainage path of the Denver air mass that has been “cooking” gives either a warning of the events to come 

or the results of the day's exposure. The site serves as a good drainage location but it may be a target for 

deletion or relocation farther down the South Platte River valley from Denver. 

Denver CAMP, 2105 Broadway (08 031 0002) 

The City and County of Denver is located approximately 30 miles east of the foothills of the 

Rocky Mountains. Denver sits in a basin and the terrain of the city is characterized as gently rolling hills 

with the Platte River running from southwest to northeast just west of the downtown area. 

However, this site represents a location typical of most of the downtown Denver area. This area 

has similar land uses, VMT (vehicle miles traveled) and sulfur dioxide sources. The Division has shown 

that the downtown Denver area and the fringe area surrounding the downtown area is homogeneous and 

indicates that the CAMP station is representative of a wider area. Thus, the CAMP sulfur dioxide site is 

representative of a neighborhood scale area. 

Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

 The Denver Municipal Animal Shelter (DMAS) was established as a replacement for the Denver 

Gates particulate monitor that was located at 1050 S. Broadway about one half mile south-southeast and 

on the other side of the South Platte River and I-25 South. The DMAS location represents the core area of 

the South Platte drainage in Denver. It has a good mixture of light industrial, residential areas and is 

strongly affected by the mobile sources along I-25 as well as South Santa Fe Drive. The openness of the 

area also permits the data to be representative of the larger core Denver area. Finally the site is on City 

owned property and will presumably be available for long-term trend analysis. When fully developed the 

site will be established as the NCore site for the Denver Metropolitan area. 

Colorado Air Monitoring Network Plan – 2009 - 2010 38
Appendix E - Meteorological Site Descriptions 

Commerce City, 7101 Birch Street (08 001 0006) 

The Commerce City monitor is located on the roof of the Alsup Elementary School. It began 

operation in November of 2001. The Commerce City site is in a predominantly residential area north of 

the Denver Central Business District (CBD) near the Platte River valley downstream from the Denver 

urban air mass. 

Welby, 3174 E. 78th Avenue (08 001 3001) 

The Welby site began operation in July 1973. The site is located along the bank of the South 

Platte River downstream from the Denver CBD. Welby is one of the longest continuously operating 

monitoring sites in the system. 

Highland Reservoir, 8100 S. University Boulevard (08 005 0002) 

The Highlands site began operation in 1978. It was intended to be a background location. 

However, with urban growth and the construction of C - 470, it has become a long-term trend site that 

monitors changes in the air quality of the area. It is a good orientation downwind from the Denver CBD. 

Aurora – East, 36001 Quincy Ave. (08 005 0006) 

 The Aurora East site began operation in June 2009. It is intended to act as a background site and 

an aid in the determination of the easternmost extent of the ozone “cloud” in the metro area. It is located 

along the eastern edge of the former Lowry bombing range, on a flat, grassy plains area. This site is 

currently outside of the rapid urban growth area taking place around Aurora Reservoir. There are 

currently plans to begin developing the Lowry area in the near future, however, which would shift the 

focus of this site from being a background site to an urban corridor site. 

Denver CAMP, 2105 Broadway (08 031 0002) 

The City and County of Denver is located approximately 30 miles east of the foothills of the 

Rocky Mountains. Denver sits in a basin and the terrain of the city is characterized as gently rolling hills 

with the Platte River running from southwest to northeast just west of the downtown area. 

The winds at the CAMP site are strongly affected by the street canyon effect of the downtown 

buildings. Meteorological data shows that winds are predominately from the south, south-southwest, 

north and north-northwest. However, due to the downtown location of this site, winds are shown to flow 

from almost all directions at similar frequencies. 

Denver - Carriage, 2325 Irving Street (08 031 0014) 

The Denver Carriage site is located 2.5 miles west of the CBD. The site represents an ideal 

neighborhood exposure setting due to its unique location in an old carriage lot in the center of the block 

surrounded by houses. 

Auraria Met, 12th Street & Auraria Parkway (08 031 0021) 

The Auraria meteorological monitor is located at the edge of the athletic fields and next to the 

parking lot for Metropolitan State College/ CU Denver. The monitor is 230 feet away from the Auraria 

Parkway and 350 feet from Speer Boulevard. It is one of the few locations in the CBD were wind data 

will be little affected by the street canyon effect of the buildings. 

Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

Colorado Air Monitoring Network Plan – 2009 - 2010 39

 The Denver Municipal Animal Shelter was established as a replacement for the Denver Gates 

particulate monitor that was located at 1050 S. Broadway about one half mile south-southeast and on the 
other side of the South Platte River and I-25 South. The DMAS location represents the core area of the 

South Platte drainage in Denver. Meteorological monitoring is expected to begin in the summer of 2007. 

Chatfield Reservoir, 11500 N. Roxborough Park Road (08 035 0004) 

The Chatfield Reservoir location was established as the result of the 1993 Summer Ozone Study. 

The site is located on the south side of Chatfield Reservoir at the Park offices. This location is away from 

the influence of trees and other influences. 

Arvada, 9101 W. 57th Avenue (08 059 0002) 

The city of Arvada is located 15 miles west-northwest of the Denver CBD. The Arvada site began 

operation before 1973. It’s location to the northwest of the Denver CBD near the western end of the 

diurnal midday wind flow of the ozone “cloud” and development in the area make this a good population 

oriented site. 

Welch, 12400 W. Highway 285 (08 059 0005) 

The Welch site is located off State Highway 285 between Kipling Street and C-470. It is 

approximately 11 miles southwest of the Denver CBD and located between the drainages of Bear Creek 

and Turkey Creek. It is in position to monitor the southern flow that occurs during the upslope, daytime 

warming period and the northern flow, which occurs during late afternoon and nighttime when drainage is 

caused by cooling and settling. 

Rocky Flats - N, 16600 W. Highway 128 (08 059 0006) 

The Rocky Flats - N site is located north-northeast of the plant on the south side of Colorado 

Highway 128, approximately 11⁄4 miles to the west of Indiana Street. The site began operation in June 

1992 as a part of the first phase of the APCD’s monitoring effort around the Rocky Flats Environmental 

Technology Site. It has continued after the closing of Rocky Flats because it is one of the highest 

concentration ozone monitors in the state. 

Rocky Flats - SE, 9901 Indiana Street (08 059 0008) 

 This site is located along Indiana Street southeast of Rocky Flats. The winds at this location are 

appreciably different from either the Rocky Flats North site or the Arvada site. 

Aspen Park, 26137 Conifer Road (08 059 0013) 

 The Aspen Park site began operation in May 2009. It is intended to verify/refute model 

predictions of above normal ozone levels. In addition, passive ozone monitors used in the area in a 2007 

study indicated the possibility of larger than normal ozone levels. The monitor is located in an urban 

setting at a Park N Ride facility off of Highway 285, at an elevation of just over 8,100 feet. Because the 

site is nearly 3,000 feet higher than the average metro area elevation, it should see ozone levels that are 

larger than those seen in the metro area, as ozone concentrations increase with increasing elevation. 

Whether or not the increased concentrations will be a health concern will be determined with the data 

gathered from this monitor. 

Rist Canyon, 11838 Rist Canyon Road, (08 069 0011) 

 The Rist Canyon site began operation in May 2009. The monitor is located within the Rist 

Canyon Volunteer Fire Department Station Number 1, in the foothills west of Fort Collins. The monitor is 

at an elevation of 6,750 feet, which is roughly 1,600 feet above the Fort Collins – West monitor. Model 

predictions have indicated the development of larger than normal ozone levels in this area. The site is 

intended to verify/refute the model prediction. 

Colorado Air Monitoring Network Plan – 2009 - 2010 40
Fort Collins - Mason, 708 S. Mason Street (08 069 1004) 

The Mason Street site is the only meteorological site operated by the APCD in the Fort Collins 

area. 

Grand Junction - Pitkin, 6451⁄4 Pitkin Avenue (08 077 0018) 

This location monitors carbon monoxide, wind speed, wind direction, temperature and hourly 

PM10. It is located at the northern edge of a low usage parking lot near the Powell monitor. 

Palisade Water Treatment, Rapid Creek Rd (08 077 0020) 

 The Palisade site is located at the Palisade Water Treatment Plant. The site is 4km to the eastnortheast of downtown Palisade, just into the De Beque Canyon area. The site is remote from any 

significant population and was established to measure maximum concentrations of ozone that may result 

from summertime up-flow conditions into a topographical trap. Monitoring commenced in May 2008. 

Lamar Port of Entry, 7100 US Highway 50, (08 099 0003) 

 The particulate monitors in Lamar have recorded some of the highest readings in the state. These 

readings are primarily associated with east winds in excess of 20 mph. The Division first established a 

meteorological monitor in Lamar at the Municipal Building but this location was too protected and the 

monitor was moved to the Port of Entry location in March of 2005. 

Colorado Air Monitoring Network Plan – 2009 - 2010 41
Appendix F - PM10 Site Descriptions 

Commerce City, 7101 Birch Street (08 001 0006) 

The Commerce City site is in a predominantly residential area north of the Denver Central 

Business District (CBD) near the Platte River valley downstream from the Denver urban air mass. There 

are two schools in addition to the Alsup Elementary school in the immediate vicinity; a middle school and 

a high school. There is a large industrial area to the south and gravel pits to the west and northwest. This 

is a good location to capture particulate matter pollution draining down the Platte River Valley from 

downtown Denver and up slope valley flows from the Greeley area. Adams City/Commerce City has 

historically shown high PM10 concentrations as well. 

Welby, 3174 E. 78th Avenue (08 001 3001) 

Welby is located 8 miles north-northeast of the Denver CBD on the bank of the South Platte 

River; this site is ideally located to measure nighttime drainage of the air mass from the Denver 

metropolitan area and the thermally driven, daytime upriver flows. It is located in the up and down river 

drainage path of the Denver air mass that has been “cooking” gives either a warning of the events to come 

or the results of the day's exposure. The site serves as a good drainage location but it may be a target for 

deletion or relocation farther down the South Platte River valley from Denver. 

Alamosa - ASC, 208 Edgemont Boulevard (08 003 0001) 

This Alamosa site is located on the science building of Adams State College in a principally 

residential area. The only significant traffic is on US 160 through the center of town. The site is along this 

highway but far enough away to reduce impacts on the levels. Meteorological data are not available from 

the area. The city has a population of 8,458 (July 2007 population estimate). This is an increase of 6.2 

percent from the 2000 census. The major particulate source is wind-blown dust. This site began operation 

in 1973 as a TSP monitor and was changed to a PM10 monitor in June 1990. 

Alamosa - Municipal, 425 4th Street (08 003 0003) 

 The Alamosa 425 4th Street was started in May 2002. The site was established closer to the center 

of the city to be more representative of the population exposure in the area. 

Pagosa Springs, 309 Lewis Street (08 007 0001) 

The Pagosa Springs site was located on the roof of the Town Hall from April 24, 2000 through 

May 2001. When the Town Hall building was planned to be demolished, the PM10 monitor was relocated 

to the Pagosa Springs Middle School and the first sample was collected on June 7, 2001. 

The Pagosa Springs Middle School site is located next to Highway 160 near the center of town. 

Pagosa Springs is a small town spread over a large area. The San Juan River runs through the south side 

of town. The town sits in a small bowl like setting with hills all around. A small commercial strip area 

along Highway 160 and single-family homes surrounds this location. It is representative of residential 

neighborhood exposure. Pagosa Springs was a PM10 nonattainment area and a SIP was implemented for 

this area. PM10 concentrations were exceeded a few times in the late 1980’s. However, the PM10 pollution 

was cleaned up through the SIP control measures and the area has only exceeded the PM10 standard once 

since 1994 and that was a regional blowing dust event in March of 1999. 

Winds for this area predominantly blow from the north, with secondary winds from the northnorthwest and the south. The predominant wind directions closely follow the valley topography in this 

rugged terrain. McCabe Creek, which is very near the meteorological station that was on the Town Hall 

building, runs north south through this area. 

Colorado Air Monitoring Network Plan – 2009 - 2010 42
Longmont, 350 Kimbark Street (08 013 0003) 

The town of Longmont is a growing, medium sized; Front Range community Longmont is 

located between the Denver/Boulder Metro-area and Fort Collins. Longmont is both suburban and rural in 

nature. The town of Longmont is located approximately 30 miles north of Denver along the St. Vrain 

Creek and is about six miles east of the foothills. Longmont is partly a bedroom community for the 

Denver-Boulder area. The elevation is 4978 feet. The Front Range peaks rise to an elevation of 14,000 

feet just to the west of Longmont. In general, the area experiences low relative humidity, light 

precipitation and abundant sunshine. 

Longmont’s predominant wind direction is from the north through the west due to winds draining 

from the St. Vrain Creek Canyon. The PM10 site is near the center of the city near both commercial and 

residential areas. This location provides the best available monitoring for population exposure to 

particulate matter. The distance and traffic estimate for the controlling street easily falls into the 

neighborhood scale in accordance with federal guidelines found in 40 CFR, Part 58, Appendix D. 

Boulder Chamber of Commerce, 2440 Pearl Street (08 013 0012) 

The city of Boulder is located on the eastern edge of the Rocky Mountain foothills. Most of the 

city sits on rolling plains. The Boulder PM2.5 site is approximately 7,000 feet east of the base of the Front 

Range foothills and about 27.4 feet south of a small branch of Boulder Creek, the major creek that runs 

through Boulder. 

The predominant wind direction is from the west with secondary maximum frequencies from the 

west-northwest and west-southwest. The distance and traffic estimate for Pearl Street and Folsom Street 

falls into the neighborhood scale in accordance with federal guidelines found in 40 CFR, Part 58, 

Appendix D. 

Delta, 560 Dodge Street (08 029 0004) 

Delta is a small agricultural community midway between Grand Junction and Montrose. 

Louisiana Pacific's plywood manufacturing facility is only major point source of particulate matter in the 

area. The topography in and around Delta is relatively flat as it sits in the broad flat Uncompaghre River 

Valley. There are high mesas and mountains surrounding this high valley. Delta sits in a large bowl 

shaped basin that can effectively trap air pollution especially during persistent temperature inversions. 

The Delta County Health Department site was chosen because it is a one story building near the 

downtown area. The site is representative of the large basin with the potential for high PM10 due to 

agricultural burning, automobile traffic and the Louisiana Pacific plant. 

Denver CAMP, 2105 Broadway (08 031 0002) 

The City and County of Denver is located approximately 30 miles east of the foothills of the 

Rocky Mountains. Denver sits in a basin and the terrain of the city is characterized as gently rolling hills 

with the Platte River running from southwest to northeast just west of the downtown area. 

Meteorological data gathered at the CAMP monitoring station is inconclusive for evaluation of 

the location as a PM10 micro-scale site. The winds are strongly affected by the street canyon effect of the 

downtown buildings. Meteorological data shows that winds are predominately from the south, southsouthwest, north and north-northwest. However, due to the downtown location of this site, winds are 

shown to flow from almost all directions at similar frequencies. Modeling of the emissions, traffic volume 

and history show that the CAMP monitor is well situated to be a maximum concentration, micro-scale 

site. However, this site represents a location typical of most of the downtown Denver area. This area has 

similar land uses, VMT (vehicle miles traveled) and PM10 sources. The Division has shown that the 

downtown Denver area and the fringe area surrounding the downtown area is homogeneous and indicates 

that the CAMP station is representative of a wider area than just its own micro-scale stetting. 

Colorado Air Monitoring Network Plan – 2009 - 2010 43
Denver Visitor Center, 225 W. Colfax Avenue (08 031 0017) 

The Denver Visitor Center site is located near the corner of Colfax Avenue and Tremont Street. It 

began operation on December 28, 1992. In 1993, this site along with the Denver CAMP and Gates 

monitors recorded the first exceedances of the 24-hour PM10 standard in the Denver metropolitan area 

since 1987. The Visitor Center recorded a PM10 level of 161 μg/m3

 on January 14, 1993. Since then, the 

maximum value recorded at the site has been 119 μg/m3

 in 2001. In the past ten years, the 24-Hour 

maximum levels have trended downward while the annual average has been relatively flat remaining 

around 25 μg/m3

. 

Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

The Denver Municipal Animal Shelter was established as a replacement for the Denver Gates 

particulate monitoring site that was located at 1050 S. Broadway about one half mile south-southeast and 

on the other side of the South Platte River and I-25 South. The DMAS location represents the core area of 

the South Platte drainage in Denver. It has a good mixture of light industrial, residential areas and is 

strongly affected by the mobile sources along I-25 as well as South Santa Fe Drive. The openness of the 

area also permits the meteorological data to be representative of the larger core Denver area. Finally the 

site is on City owned property and will presumably be available for long-term trend analysis. When fully 

developed the site will be established as the NCore or National Core site for the Denver Metropolitan 

area. 

Colorado College, 130 W. Cache la Poudre Street (08 041 0017) 

 The Colorado College monitor was established after the revised particulate regulations required 

that Colorado Springs needed a continuous PM2.5 monitor. The Department elected to collocate the new 

PM2.5 monitor with the corresponding filter based monitors from the RBD site at the Colorado College 

location. These monitors began operation in January of 2008. 

 The nearest representative meteorological site is located at the Colorado Springs Airport. Wind 

flows at the Colorado College site are affected by its proximity to Fountain Creek, so light drainage winds 

will follow the creek in a north/south direction. 

Cañon City - City Hall, 128 Main Street (08 043 0003) 

Cañon City is located 39 miles west of Pueblo. Particulate monitoring began on January 2, 1969 

with the operation of a TSP monitor located on the roof of the courthouse building at 7th Avenue and 

Macon Street. 

The Cañon City PM10 site began operation in December 1987. On May 6, 1988, the Macon Street 

monitor recorded a PM10 concentration of 172 μg/m3

. This is the only exceedance of either the 24-hour or 

annual NAAQS since PM10 monitoring was established at Cañon City. The Macon Street site was 

relocated to the City Hall in October of 2004. 

Parachute, 100 E. 2nd Street (08 045 0005) 

The annual average has been trending upward but is still just over one half of the former annual 

standard for PM10 which was 50μg/m3

. 

Rifle - Henry Building, 144 3rd Street (08 045 0007) 

The first Rifle site began operation in June 1985 and ended operation in May 1986. The next site 

began operation in December 1987 and continued until 2001. The levels at that site, with the exception of 

the March 31, 1999 high wind event were always less than one half of both the annual and the 24-hour 

standards. The current location on the Henry Building began operation in May of 2005 as a part of the 

Garfield County study. 

Colorado Air Monitoring Network Plan – 2009 - 2010 44
Crested Butte, 603 6th Street (08 051 0004) 

The Crested Butte PM10 site began operation in June 1985. Crested Butte is a high mountain ski 

town. The monitor is at the east end of town near the highway and in the central business district. Any 

wood burning from the residential area to the west directly affects this location. The physical setting of 

the town, near the end of a steep mountain valley, makes wood burning, Street sanding and wintertime 

inversions a major concern. The town is attempting to regulate the number of wood burning appliances, 

since this is a major source of wintertime PM10. Crested Butte has not recorded an exceedance of the 

NAAQS since it began monitoring. 

Mt. Crested Butte, 19 Emmons Road (08 051 0007) 

Mount Crested Butte is located at an elevation of 8,940 feet (2,725 m) at the base of the Crested 

Butte Mountain Resort ski area. Mount Crested Butte is a unique location for high particulate matter 

concentrations because it is located on the side of a mountain (Crested Butte 12,162 ft. or 3,707 m), not in 

a bowl, valley, or other topographic feature that would normally trap air pollutants. There is not a 

representative meteorological station in or near Mt. Crested Butte. 

The location for the Mt. Crested Butte site was selected because it had an existing PM10 site that 

had several high PM10 concentrations including five exceedances of the 24-hour standard in 1997 and one 

in 1998. Mt. Crested Butte also exceeded the PM10 annual average standard in 1997. A CMB source 

apportionment from 10 PM10 filters identified crustal material as the mostly likely source (91 percent) of 

PM10. Carbon, which is most likely from residential woodsmoke, made up 8 percent of the statistically 

composite sample and secondary species made up the remaining 1 percent. The Mt. Crested Butte site 

was also selected because it is an area representative of the residential impact of PM2.5. 

Durango - River City Hall, 1235 Camino del Rio (08 067 0004) 

Durango is the second largest city on the western slope. The town is situated in the Animas River 

Valley in southwestern Colorado. Its elevation is approximately 6,500 feet (1981 meters) above mean sea 

level. The Animas valley through Durango is steep and narrow. Even though little meteorological 

information is available for the area, the microclimate of Colorado mountain communities is characterized 

by cold air subsidence, or drainage flows during the evening and early morning hours and up valley flows 

during afternoon and early evening hours when solar heating is highest. Temperature inversions that trap 

air pollutants near the surface are common during night and early morning hours. 

Fort Collins - CSU, 251 Edison Street (08 069 0009) 

Fort Collins does not have the population to require a particulate monitor under Federal 

regulation. However, it is one of the largest cities along the Front Range. 

Grand Junction - Powell, 650 South Avenue (08 077 0017) 

Grand Junction is the largest city on the western slope in the broad valley of the Colorado River. 

The monitors are on county owned buildings in the south side of the city. The site is on the southern end 

of the central business district and close to the industrial area along the train tracks. It is about a half a 

mile north of the river and about a quarter mile east of the railroad yard. This site monitors 24-hour and 

hourly PM10 as well asfor 24-hour and hourly PM2.5 and PM2.5 Speciation. 

Grand Junction - Pitkin, 6451⁄4 Pitkin Avenue (08 077 0018) 

This location monitors carbon monoxide, wind speed, wind direction, temperature and hourly 

PM10. It is located at the northern edge of a low usage parking lot near the Powell monitor. 

Clifton, Hwy 141 & D Road (08 077 0019) 

Colorado Air Monitoring Network Plan – 2009 - 2010 45

 The Clifton monitor is located in the town of Clifton which is a southeastern suburb of Grand 

Junction, Colorado. The monitor is in a low usage parking lot operated by the sanitation district. It is one 
half mile north of the Colorado River. The site was established at the request of the Mesa County Health 

Department to address concerns of the oil and gas development in the area. 

 The monitor began operations in October 2007 and operates on an every third day schedule. 

Aspen - Library, 120 Mill Street (08 097 0006) 

Aspen is at the upper end of a steep mountain valley. The major difference is that Aspen does not 

have an interstate running through it. Aspen was classified as nonattainment for PM10 but it is now under 

an attainment/maintenance plan. The valley is more restricted at the lower end and thus forms a tighter 

trap for pollutants in the valley. The transient population due to winter skiing and summer mountain 

activities greatly increases the population and traffic during these seasons. There is also a large down 

valley population that commutes to work each day from as far away as the Glenwood Springs area 41 

miles to the northeast. 

There have been several particulate monitors in the Aspen area. Only three have not been shortterm special studies. The first PM10 monitor began operation in June 1985. The next, the Sport Stalker, 

was chosen after an intense effort involving EPA, State and local agency personnel. The need was to find 

an acceptable middle or middle scale location. 

Lamar Power Plant, 100 2nd Street (08 099 0001) 

Lamar is one of the largest cities on the eastern plains. Particulate monitoring in Lamar began in 

August 1975 with the installation of a TSP site at the Lamar power plant at 100 2nd Street. It operated as a 

TSP site until August of 1986. The first Lamar PM10 site began operation in June 1985 at the power plant. 

In August 1986, the monitoring site was moved to the Municipal Complex (08 099 0002). 

On March 19, 1976, the Lamar power plant monitor recorded a TSP of 1,033 μg/m3

. This is the 

fourth highest particulate concentration ever reported in Colorado. Lamar has regularly recorded its 

highest TSP and PM10 levels in March. Between 1975 and 1986 the power plant monitor reported 25 

concentrations greater than the 24-hour TSP NAAQS of 260 μg/m3

, twelve of these occurred in March, 

no other month had more than three. Three of the seven exceedances of the 24-hour PM10 NAAQS have 

also occurred in March. The primary reason for this relationship is due to the combination of low 

humidity and high winds that are common during the month of March. Lamar is the only Colorado city 

east of Denver to have been designated as a PM10 nonattainment area and is now under an 

attainment/maintenance plan. In 1992, the Division reinstated the power plant location as well. This was 

done after a review showed that levels at the power plant were generally higher than those at the City 

Complex. As a part of the SIP for Lamar, a meteorological site was established in 1992 at the city 

complex location. Analysis of these data was included as a part of the SIP process. 

Lamar - Municipal Building, 104 Parmenter Street (08 099 0002) 

 The Lamar Municipal site was established in January of 1996 as a more population oriented 

location than the Power Plant. The Power Plant site is located on the northern edge of town while the 

Municipal site is near the center of the town. Both sites have recorded exceedances of the 24-hour 

standard of 150 μg/m3

 and both sites regularly record values above 100μg/m3 as a 24-hour average. 

Pueblo - Public Works, 211 E. D Street (08 101 0012) 

Pueblo is the third largest city in the state, not counting communities that are part of Metropolitan 

Denver. Pueblo is principally characterized by rolling plains and moderate slopes with elevations ranging 

from 4,474 ft to 4,814 ft (1,364 to 1,467 m). The Rocky Mountain Front Range is about 25 miles (40 km) 

west and the sight of Pikes Peak is easily visible on a clear day. 

Colorado Air Monitoring Network Plan – 2009 - 2010 46

Meteorologically, Pueblo can be described as having mild weather with an average of about 300 

days of sunshine per year. Generally, wind blows up valley from the southeast during the day and down 

valley from the west at night. Pueblo experiences average wind speed ranges from 7 miles per hour in the 

fall and early winter to 11 miles per hour in the spring. 
The site is located on the roof of the Public Works Building at 211 E. D St., in a relatively flat 

area found two blocks northeast of the Arkansas River. It is also located near Fountain Creek. The 

distance and traffic estimate for Main Street and surrounding streets easily falls into the middle scale in 

accordance with federal guidelines found in 40 CFR, Part 58, Appendix D. 

The Division is in the process of finding a location for the Pueblo monitors since a new tall 

building is under construction adjacent to the monitors. 

Steamboat Springs, 136 6th Street (08 107 0003) 

Like other ski towns, Steamboat Springs has problems with wintertime inversions, high traffic 

density, wood smoke and street sand. These problems are exacerbated by temperature inversions that trap 

the pollution in the valleys. 

The first site began operation in Steamboat Springs in June 1985 at 929 Lincoln Avenue. It was 

moved to the current location in October 1986. The 136 6th Street location not only provides a good 

indication of population exposure, since it is more centrally located, but it has better accessibility than the 

previous location. 

Telluride, 333 W. Colorado Avenue (08 117 0002) 

Telluride is a high mountain ski town in a narrow box end valley. The San Miguel River runs 

through the south end of town and the town is only about 1⁄2 mile wide from north to south. The 

topography of this mountain valley regime creates temperature inversions that can last for several days 

during the winter. Temperature inversions can trap air pollution close to the ground. Telluride sits in a 

valley that trends mainly east to west, which can trap air pollutants more effectively since the prevailing 

winds in this latitude are the westerly and the San Miguel River Valley is closed off on the east end. 

Breckenridge - 501 N. Park Avenue (08 119 0002) 

The City of Breckenridge is located in the valley of the Blue River. It is a tourist center with 

skiing in the winter and numerous summertime festivals and activities. The resulting woodsmoke and 

traffic caused sufficient concern that the city of Breckenridge requested that the Division establish PM10

monitoring in the area. The Breckenridge site began operation in April 1992 and it recorded exceedances 

of the level of the 24-hour standard in both 2000 and in 2005. The site is currently operating on an every 

third day sampling schedule. 

Greeley - Hospital, 1516 Hospital Road (08 123 0006) 

Winds in this area are primarily out of the northwest; with dominant wind speeds less than 3.1 

m/s. Secondary winds are from the north, north-northwest and east-southeast, with the most frequent wind 

speeds also being less than 3.1 m/s. The most recent available wind data for this station is for the period 

December 1986 to November 1987. Predominant residential growth patterns are to the west and north 

with large industrial growth expected to the west. There are two feedlots located about 11 miles east of 

the town. There was a closer feedlot on the east edge of town, but it was moved in early 1999, after the 

town of Greeley purchased the land in 1997. 

The Greeley PM10 monitor is on the roof of a hospital office building at 1516 Hospital Road. 

Greeley Central High School is located immediately to the east of the monitoring site. Overall, this is in 

an area of mixed residential and commercial development that makes it a good population exposure, 

neighborhood scale monitor. The distance and traffic estimate for the most controlling street easily falls 

into the neighborhood scale in accordance with federal guidelines found in 40 CFR, Part 58. 

Colorado Air Monitoring Network Plan – 2009 - 2010 47
Appendix G - PM2.5 Site Descriptions 

Commerce City, 7101 Birch Street (08 001 0006) 

The Commerce City site is in a predominantly residential area north of the Denver Central 

Business District (CBD) near the Platte River valley downstream from the Denver urban air mass. There 

are two schools in addition to the Alsup Elementary School in the immediate vicinity, a middle school to 

the north and a high school to the southeast. There is a large industrial area to the south and gravel pits to 

the west and northwest. This is a good location to capture particulate matter pollution draining down the 

Platte River Valley from downtown Denver and up slope valley flows from the Greeley area. The old 

Adams City/Commerce City site, which was about 180 meters north of the Alsup Elementary School, 

recorded high PM10 concentrations as well. 

Arapahoe Community College, 6190 S. Santa Fe Drive (08 005 0005) 

The ACC site is located in south suburban metropolitan Denver. It is located on the south side of 

the Arapahoe Community College in a distant parking lot. The site is near the bottom of the Platte River 

Valley along Santa Fe Drive (Hwy. 85) in the city of Littleton. It is also near the city of Englewood. 

There is a large residential area located to the east across the railroad and Light Rail tracks. The PM2.5

monitor is located on a mobile shelter in the rarely used South parking lot. Located at 6190 S. Santa Fe 

Drive, this small trailer is close to the Platte River and the monitor has excellent 3600

 exposure. Based on 

the topography and meteorology of the area ACC is in an area where PM2.5 emissions may collect. This 

location may capture high concentrations during periods of upslope flow and temperature inversion in the 

valley. However, since it is further south in a more sparsely populated area than the Broadway-CAMP 

site, the concentrations are usually not as high as other Denver locations. 

Winds are predominately out of the south-southwest and south, with secondary winds out of the 

north and north-northeast (upslope). Observed distances and traffic estimates easily fall into the 

neighborhood scale in accordance with federal guidelines found in the 40 CFR, Part 58, Appendix D. The 

site meets all other neighborhood scale criteria. 

Longmont, 350 Kimbark Street (08 013 0003) 

The town of Longmont, located in Boulder County, is a growing, medium sized, Front Range 

community. It is located approximately 30 miles north of Denver along the St. Vrain Creek and is about 

six miles east of the foothills. Longmont is partly a bedroom community for the Denver-Boulder area. 

The elevation is 4,978 feet. The Front Range peaks rise to an elevation of 14,000 feet just to the west of 

Longmont. In general, the area experiences low relative humidity, light precipitation and abundant 

sunshine

Longmont’s predominant wind direction is from the north through the west due to winds draining 

from the St. Vrain Creek Canyon. The PM2.5 site is near the center of the city near both commercial and 

residential areas. This location provides the best available monitoring for population exposure to 

particulate matter. The distance and traffic estimate for the AADT controlling street easily falls into the 

neighborhood scale in accordance with federal guidelines found in 40 CFR, Part 58, Appendix D. 

Boulder Chamber of Commerce, 2440 Pearl Street (08 013 0012) 

The city of Boulder is located on the eastern edge of the Rocky Mountain foothills. Most of the 

city sits on rolling plains. The Boulder PM2.5 site is approximately 7,000 feet (2.13 km) east of the base of 

the Front Range foothills and about 27.4 feet (8.35 m) south of a small branch of Boulder Creek, the 

major creek that runs through Boulder. 

Colorado Air Monitoring Network Plan – 2009 - 2010 48

The predominant wind direction is from the west with secondary maximum frequencies from the 

west-northwest and west-southwest. The distance and traffic estimate for Pearl Street and Folsom Street 

falls into the neighborhood scale in accordance with federal guidelines found in 40 CFR, Part 58, 
Appendix D. Thus, the Boulder Chamber of Commerce PM2.5 site is representative of a neighborhood 

scale area and meets all other neighborhood scale criteria. 

Boulder - CU/Athens, 2102 Athens Street (08 013 1001) 

The Boulder - CU site is located at the edge of a low usage parking lot to the north and the 

football practice field to the south. This location provides a good neighborhood representation for 

particulates. This site will be removed in 2009 due to construction of a new domed practice field. 

Denver CAMP, 2105 Broadway (08 031 0002) 

The City and County of Denver is located approximately 30 miles east of the foothills of the 

Rocky Mountains. Denver sits in a basin and the terrain of the city is characterized as gently rolling hills 

with the Platte River running from southwest to northeast just west of the downtown area. 

Meteorological data gathered at the CAMP monitoring station is inconclusive for evaluation of 

the location as a PM2.5 micro-scale site. The winds are strongly affected by the street canyon effect of the 

downtown buildings. Meteorological data shows that winds are predominately from the south, southsouthwest, north and north-northwest. However, due to the downtown location of this site, winds are 

shown to flow from almost all directions at similar frequencies. Modeling of the emissions, traffic volume 

and history show that the CAMP monitor is well situated to be a maximum concentration, micro-scale 

site. However, this site represents a location typical of most of the downtown Denver area. This area has 

similar land uses, VMT (vehicle miles traveled) and PM2.5 sources. The Division has shown that the 

downtown Denver area and the fringe area surrounding the downtown area is homogeneous and indicates 

that the CAMP station is representative of a wider area than just its own micro-scale area. 

Denver NJH-E, 14th Avenue & Albion Street (08 031 0013) 

This site is located three miles east of the Denver CBD, close to one of the busiest intersections in 

Denver (Colorado Boulevard and Colfax Avenue). The current site began operations in 1982. Two 

previous sites were located just west of the current location. The first operated for only a few months 

before it was moved to a new and “temporary” site in the corner of the laboratory building at the corner of 

Colorado Boulevard and Colfax Avenue. 

Denver - Swansea, 4650 Columbine Street (08 031 0023) 

The Swansea Elementary school site was established as a part of the toxicological study 

associated with the ASARCO Study conducted by the Colorado Department of Public Health and 

Environment. 

Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

 The Denver Municipal Animal Shelter was established as a replacement for the Denver Gates 

monitor that was located at 1050 S. Broadway about one half mile south-southeast and on the other side 

of the South Platte River and I-25 South. The DMAS location represents the core area of the South Platte 

drainage in Denver. It has a good mixture of light industrial, residential areas and is strongly affected by 

the mobile sources along I-25 as well as South Santa Fe Drive. The openness of the area also permits the 

meteorological data to be representative of the larger core Denver area. Finally the site is on City owned 

property and will presumably be available for long-term trend analysis. When fully developed the site will 

be established as the NCore site for the Denver Metropolitan area. 

Chatfield Reservoir, 11500 N. Roxborough Park Road (08 035 0004) 

Colorado Air Monitoring Network Plan – 2009 - 2010 49

The Chatfield Reservoir location was established as the result of the 1993 Summer Ozone Study. 

The site is located on the south side of Chatfield Reservoir at the campground registration building. This 

location was selected over the Corps of Engineers Visitor Center across the reservoir because it was more 
removed from the influence of traffic along C-470. Located in the South Platte River drainage, this 

location is well suited for monitoring southwesterly PM2.5 particulates in the Denver metro area. 

Elbert County, 24950 Ben Kelly Road (08 039 0001) 

The Elbert County site is believed to be a good location to measure urban background 

concentrations of PM2.5. Winter winds at Elbert are from the southwest to southeast at 4-5 m/s during the 

morning hours. During the afternoon hours, brisk winds are generally from the south-southwest to the 

southeast. This shows that the Denver Metropolitan Area does not influence the winds moving across the 

monitoring site. A July 1981 analyses of surface streamline was done to study summer wind patterns in 

this same area. The study shows that in the later morning hours (0800), winds predominately blow from 

the north and northeast, placing the Denver Metro-Area upwind of the site. Although, during the early 

morning hours, wind flows off the Cheyenne Ridge and Palmer Lake Divide into the river basins to the 

north and south, away from the Elbert County monitoring site. By early afternoon (1100) and continuing 

through later afternoon (1400), up slope flow occurs over nearly the entire region, bringing clean air from 

the east and northeast to the site. By the evening hours, winds again predominately flow from the 

mountain region, with these westerly winds again flowing off the Palmer Lake Divide, away from the 

monitoring site. This would suggest that the Elbert County site is a very clean location for winter months 

and for early morning, afternoon and evening hours during the summer months. 

The location of this Elbert County site classifies it as an urban background site, in accordance 

with federal guidelines found in 40 CFR, Part 58, Appendix D. The site meets all guidelines for the urban 

background site. 

Colorado College, 130 W. Cache la Poudre Street (08 041 0017) 

 The Colorado College monitor was established after the revised particulate regulations required 

that Colorado Springs needed a continuous PM2.5 monitor. The Department elected to collocate the new 

PM2.5 monitor with the corresponding filter based monitors from the RBD site at the Colorado College 

location. These monitors began operation in January of 2008. 

 The nearest representative meteorological site is located at the Colorado Springs Airport. Wind 

flows at the Colorado College site are affected by its proximity to Fountain Creek, so light drainage winds 

will follow the creek in a north/south direction. 

Fort Collins - CSU, 251 Edison Street (08 069 0009) 

Fort Collins does not have the population to require a particulate monitor under Federal 

regulation. However, it is one of the largest cities along the Front Range. 

Grand Junction - Powell, 650 South Avenue (08 077 0017) 

Grand Junction is the largest city on the western slope in the broad valley of the Colorado River. 

The monitors are on county owned buildings in the south side of the city. The site is on the southern end 

of the central business district and close to the industrial area along the train tracks. It is about a half a 

mile north of the river and about a quarter mile east of the railroad yard. This site monitors 24-hour and 

hourly PM10 as well asfor 24-hour and hourly PM2.5 and PM2.5 Speciation. 

Pueblo - Public Works, 211 S. D Street (08 101 0012) 

Not counting communities that are part of Metropolitan Denver, Pueblo is the third largest city in 

the state. Pueblo is principally characterized by rolling plains and moderate slopes with elevations ranging 

from 4,474 ft to 4,814 ft. The Rocky Mountain Front Range is about 25 miles west and the sight of Pikes 

Peak is easily visible on a clear day. 

Colorado Air Monitoring Network Plan – 2009 - 2010 50

Meteorologically, Pueblo can be described as having mild weather with an average of about 300 

days of sunshine per year. Generally, wind blows up valley from the southeast during the day and down 
valley from the west at night. Pueblo experiences average wind speed ranges from 7 miles per hour in the 

fall and early winter to 11 miles per hour in the spring. 

The site is located on the roof of the Public Works Building at 211 S. D St., in a relatively flat 

area found two blocks northeast of the Arkansas River. It is also located near Fountain Creek. The 

distance and traffic estimate for Main Street and surrounding streets easily falls into the neighborhood 

scale in accordance with federal guidelines found in 40 CFR, Part 58, Appendix D. 

The Division is in the process of finding a location for the Pueblo monitors since a new tall 

building is under construction adjacent to the monitors. 

Greeley - Hospital, 1516 Hospital Road (08 123 0006) 

The current Greeley site has been in operation since 1982. 

Winds in this area are primarily out of the northwest; with dominant wind speeds less than 3.1 

m/s. Secondary winds are from the north, north-northwest and east-southeast, with the most frequent wind 

speeds also being less than 3.1 m/s. The most recent available wind data for this station is for the period 

December 1986 to November 1987. Predominate residential growth patterns are to the west and north 

with large industrial growth expected to the west. There are two feedlots located about 11 miles east of 

the town. There was a closer feedlot on the east edge of town, but it was moved at the first of 1999, after 

the town of Greeley purchased the land in 1997. 

The Greeley PM2.5 monitor is on the roof of a hospital office building at 1516 Hospital Road. 

Greeley Central High School is located immediately to the east of the monitoring site. Overall, this is in 

an area of mixed residential and commercial development that makes it a good population exposure, 

neighborhood scale monitor. The distance and traffic estimate for the most controlling street easily falls 

into the neighborhood scale in accordance with federal guidelines found in 40 CFR, Part 58, Appendix D. 

Platteville, 1004 Main Street (08 123 0008) 

Platteville is located immediately west of Highway 85 along the Platte River valley bottom four 

miles east of I 25, at an elevation of 4,825 feet. The area is characterized by relatively flat terrain and is 

located about one mile east of the South Platte. The National Oceanic and Atmospheric Administration 

operated the PROFS (Prototype Regional Observational Forecasting System) Mesonet network of 

meteorological monitors from the early 1980's through the mid 1990's in the northern Colorado Front 

Range area. Based on this data, the area around Platteville is one of the last places in the wintertime that 

the cold pool of air that is formed by temperature inversions burns off. This is due to solar heating. The 

upslope/downslope Platte River Valley drainage and wind flows between Denver and Greeley make 

Platteville a good place to monitor PM2.5. These characteristics also make it an ideal location for chemical 

speciation sampling, which began at the end of 2001. 

The Platteville site is located at 1004 Main Street at the South Valley Middle School, located on 

the south side of town on Main Street. The school is a one-story building and it has a roof hatch from a 

locked interior room providing easy access to its large flat roof. There is a 2-story gym attached to the 

building approximately 28 meters to the Northwest of the monitor. The location of the Platteville monitor 

easily falls into the regional transport scale in accordance with federal guidelines found in 40 CFR, Part 

58, Appendix D. 

Colorado Air Monitoring Network Plan – 2009 - 2010 51
Appendix H - TSP/Lead Site Descriptions 

Denver Municipal Animal Shelter, 678 S. Jason Street (08 031 0025) 

The Denver Municipal Animal Shelter was established as a replacement for the Denver Gates 

particulate monitor that was located at 1050 S. Broadway about one half mile south-southeast and on the 

other side of the South Platte River and I-25 South. The DMAS location represents the core area of the 

South Platte drainage in Denver. It has a good mixture of light industrial, residential areas and is strongly 

affected by the mobile sources along I-25 as well as South Santa Fe Drive. The openness of the area also 

permits the meteorological data to be representative of the larger core Denver area. Finally the site is on 

city owned property and will presumably be available for long-term trend analysis. When the Denver 

Municipal Animal Shelter location is fully developed it will be established as the NCore site for the 

Denver Metropolitan area. 

Until the establishment of the new lead standard in November 2008, this monitor served as the 

CFR required regional lead site. 

Colorado Air Monitoring Network Plan – 2009 - 2010 52
Appendix I - National Core (NCore) Monitoring Station 

The Colorado Department of Public Health and Environment, Air Pollution Control Division’s 

NCore monitoring station is located on the Denver Municipal Animal Shelter (DMAS) lot at 678 S. Jason 

Street in Denver, Colorado. This location is in the Denver-Boulder Region with its projected population 

for 2008 of 2.845 million. This is a projected increase of 1.6 percent from the 2000 census. The site is 

located approximately 4 miles directly south of the Denver CBD along the South Platte River. This 

location was established as the NCore site in conjunction with EPA Region VIII and the City and County 

of Denver. 

The DMAS site was also chosen because it represented a better neighborhood scale for carbon 

monoxide, ozone and particulate matter. The site also had enough space available for the number of 

samplers required for an NCore monitoring site. Its location along the South Platte River provides 

maximum exposure to the up and down-valley pollution carried by the diurnal winds. This last point is 

supported by the wind rose. The wind rose has data only for seven months but the trend is evident. 

Area of Representativeness 

 40 CFR Part 58 Appendix provides design criteria for ambient air quality monitoring. The 

monitoring objective for the NCore site is to produce data that represents a fairly large area and therefore 

the spatial scale of the site is important. The special scale defines the physical dimensions of the air parcel 

nearest to the monitoring site throughout which actual pollutant concentrations are similar. It is 

determined by the characteristics of the area surrounding the air monitoring site and the site’s distance 

from nearby air pollution sources such as roadways, factories, etc. In the case of urban NCore the special 

scales to be used are neighborhood and urban. The following table shows the area of representativeness 

for each pollutant for the DMAS site. 

Table 14 - Parameters and Scale for the Denver Municipal Animal Shelter 

AQS # Site Name Address Started Ended Latitude Longitude Elevation 

08 031 0025 Denver Municipal 

Animal Shelter 678 S. Jason St. 07/2005 39.704005 -104.998113 1,594 

Parameter POC Started Orient/Scale Monitor Type Sample 

CO 1 05/2009 P.O. Neigh Thermo 48C-TLE NCore Continuous 

SO2 1 05/2008 P.O. Neigh Ecotech 9850T NCore Continuous 

NOY + 

O3 1 04/2008 Neigh/Urban API 400A NCore Continuous 

WS/WD/Temp (U) 1 07/2008 P.O. Neigh Met - One NCore Continuous 

Relative Humidity 1 + Rotronic NCore Continuous 

Barometric Pressure 1 + NCore Continuous

Solar Radiation 1 + NCore Continuous

Precipitation 1 + NCore Continuous

Temp (L) 1 07/2008 P.O. Neigh Met - One NCore Continuous 

TSP 1 07/2005 P.O. Neigh TSP SLAMS 1/6 

TSP 2 07/2005 P.O. Neigh TSP SLAMS 1/6 

Pb 1 07/2005 P.O. Neigh TSP SLAMS 1/6 

Pb 2 07/2005 P.O. Neigh TSP SLAMS 1/6 

PM10 1 07/2005 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

PM10 2 07/2005 P.O. Neigh SA/GMW-1200 SLAMS 1/6 

PM10 3 08/2005 P.O. Neigh TEOM-1400ab SLAMS Continuous 

PM2.5 1 10/2007 P.O. Neigh Partisol 2025 NCore 1/6 

PM2.5 3 10/2007 P.O. Neigh TEOM FDMS SPM Continuous 

PM2.5 Speciation + NCore 1/6 

+ - Indicates that these parameters have not begun operation at this time but are scheduled to begin in 2010. 

Colorado Air Monitoring Network Plan – 2009 - 2010 53

The neighborhood scale is set to represent an area up to 4 km in diameter form the site. In the 

case of the DMAS site this represents an area from the state capitol on the north almost to Colfax 
Boulevard and Alameda Avenue on the east. The southern end of the neighborhood scale area is Yale 

Avenue and Santa Fe Drive. The western boundary is almost to Alameda Avenue and Sheridan 

Boulevard. This area is a mix of residential, commercial and light industry and contains 28 schools, two 

hospitals and three clinics. The Xcel Energy’s Zuni Power Plant is located 4 km north-northwest of the 

DMAS site along the South Platte River and the Arapahoe Power Plant is 3.7 km to the south. 

 The urban scale of up to 50 km encompasses all of the Denver Metro Area and stretches from 

Longmont on the north to below Castle Rock on the south and from Bennett on the east to Idaho Springs 

on the west. The western scale boundary is more reasonably restricted to the edge of the foothill near 

Golden. 

 Traffic in the immediate area around the site is limited as shown in the following table. 

Table 15 - Traffic Information for the Denver Municipal Shelter 

Distance to 

the nearest 

roadway 

Direction Daily Traffic 

Estimates 

Year of Traffic 

Estimates 

Type of 

Roadway Comments 

58 meters North/East <2000 2008 6-local Estimates only 

East 

South 

91 meters West <2000 2008 6-local Estimates only 

Colorado Air Monitoring Network Plan – 2009 - 2010 54

 
Denver Municipal Animal Shelter Site Photos

Colorado Air Monitoring Network Plan – 2009 - 2010 55
Denver Municipal Animal Shelter (4 Km Radius) 

Colorado Air Monitoring Network Plan – 2009 - 2010 56
Denver Municipal Animal Shelter (50 Km Radius) 

Colorado Air Monitoring Network Plan – 2009 - 2010 57

 
 Wind Speed and direction measurements at the DMAS site began in July 2008. The rest of the 

suite of meteorological measurements are scheduled to begin operation in 2009 but the equipment has not 

been purchased. The following wind roses show the data from July 2008 through January 2009. 

Wind Rose July 2008 - January 2009 - All Hours 

Wind Rose July 2008 – January 2009 - AM Hours / Wind Rose July 2008 – January 2009 - PM Hours

 

Colorado Air Monitoring Network Plan – 2009 - 2010 58
Drawings of Denver Municipal Animal Shelter Site layout. 

 

Colorado Air Monitoring Network Plan – 2009 - 2010 59
Colorado Air Monitoring Network Plan – 2009 - 2010 60