SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT

ANNUAL AIR QUALITY MONITORING NETWORK PLAN

July, 2015

Deputy Executive Officer

Science and Technology Advancement

Matt Miyasato, Ph.D.

Assistant Deputy Executive Officer

Science and Technology Advancement

Laki Tisopulos, Ph.D., P.E.

Atmospheric Measurements Manager

Science and Technology Advancement

Jason Low, Ph.D. 

Authors: Rene M. Bermudez

Principal Air Quality Instrument Specialist

Brian Vlasich

Senior Air Quality Instrument Specialist

Jason Low, Ph. D

Atmospheric Measurements Manager
Air Quality Monitoring Network Plan – July, 2015

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Table of Contents

Page

Introduction 1

Public Comments 1

Network Design 1

Special Programs 19

Recent or Proposed Modifications to Network 22

Minimum Monitoring Requirements

Data Submittal and Archiving Requirements

37

44

Appendix A: Network Depiction Maps

 Ozone Monitoring Locations A-1

 PM10 Monitoring Locations A-2

 Nitrogen Dioxide Monitoring Locations A-3

 Carbon Monoxide Monitoring Locations A-4

 Sulfur Dioxide Monitoring Locations A-5

 Source and Ambient Lead Monitoring Locations A-6

 PAMS Monitoring Locations A-7

 PM2.5 Monitoring Locations A-8

Appendix B: Detailed Site Information

Appendix C: PM2.5 Continuous Monitor Comparability Assessment 

 and Request for Waiver

Appendix D:Waiver requests
Air Quality Monitoring Network Plan – July, 2015

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INTRODUCTION

An annual review of the Air Quality Monitoring Network is required by Federal Regulations as a 

means to identify and report needs for additions, relocations, or terminations of monitoring sites 

or instrumentation. This report describes the network of ambient air quality monitors in the 

jurisdiction of and operated by the South Coast Air Quality Management District (SCAQMD). It 

includes a review of actions taken during the 2014-2015 fiscal year and plans for action in the year 

ahead. This plan addresses the requirement for an annual network plan as listed in Title 40, Part 

58, Section 10 of the Code of Federal Regulations (40 CFR § 58.10). Regulations require the 

report be submitted to the U.S. Environmental Protection Agency (EPA) by July 1 of each year 

after a 30 day public comment period.

The SCAQMD staff, along with the California Air Resources Board (CARB), conducted an 

extensive review of the air monitoring sites in the South Coast Air Basin (SCAB) in late 1980. 

During the review, State and Local Air Monitoring Stations (SLAMS) designations, site type, and 

spatial scales of representativeness were assigned to the criteria pollutants monitored at each site. 

Since that time, the EPA Region IX and CARB staff visited selected sites to confirm compliance

with applicable siting criteria and related requirements. The most recent site visits occurred in 

2013 to conduct a comprehensive Technical System Audit (TSA) of the ambient air monitoring 

network. Each year, SCAQMD staff conducts an annual review of its air monitoring network and 

submits it to the EPA. The review process focuses on current and future network air monitoring 

strategies and network changes are made in consultation with the EPA and CARB. When relocation of monitoring sites is required, site reports are updated in the EPA’s Air Quality System

(AQS) to document compliance with established siting criteria for the new locations.

Public Comments 

Pursuant to Federal regulations, a draft plan is made available for public inspection and comment

for a period of 30 days prior to submission of the final plan to EPA. Hard copies of the final

document are made available on July 1, 2015 at the SCAQMD’s Public Information Desk in 

Diamond Bar, CA. The document is also available on the SCAQMD website as of May 22, 2015

in the drop down menu under the “Library”, “Clean Air Plans” and “Air Monitoring Network 

Plan.” (http://www.aqmd.gov/home/library/clean-air-plans/monitoring-network-plan). The final

document is submitted to the EPA on July 1, 2015. Public comments and responses are also 

submitted to EPA to fulfill Federal regulatory requirements. No comments were received by the 

close of the comment period on June 22, 2015.

Network Design

The SCAQMD operates 39 permanent, monitoring stations and 4 single-pollutant source impact 

Lead (Pb) air monitoring sites in the SCAB and a portion of the Salton Sea Air Basin in Coachella 

Valley. This area includes Orange County and the non-desert portions of Los Angeles, Riverside,

and San Bernardino Counties. The newest permanent sites were added as part of the near road 

monitoring network at Ontario Etiwanda and Route 60; Long beach Route 710 and Anaheim. A 

site was made permanent at Saul Martinez Elementary which monitors emissions from the Salton 

Sea The newest source impact Pb sites were added in January 2010 as required by EPA regulation. 

During 2014, the Burbank, Ontario Fire Station, and Riverside Magnolia sites were discontinued 

due to termination of leases and/or safety concerns. Table 1 provides a list of monitoring locations, 
Air Quality Monitoring Network Plan – July, 2015

2

the EPA AQS site codes, and the pollutants measured at each site. Table 2 provides the spatial 

scale and the site type for each monitor at all sites.

Table 3 describes the monitoring purpose for the monitors at each site. Table 4 describes the site 

type, spatial scale and monitoring purpose for continuous particulate analyzers at each site. A 

requirement of the annual network plan, the monitoring purpose is the reason why a certain 

pollutant is being measured at a certain site. 

A list and description of monitoring purposes are provided below and portions are adapted from 

the CARB annual network plan for 2007. 

Background Level monitoring is used to determine general background levels of air 

pollutants as they enter the SCAB.

High Concentration monitoring is conducted at sites to determine the highest concentration 

of an air pollutant in an area within the monitoring network. A monitoring network may 

have multiple high concentration sites (i.e., due to varying meteorology year to year).

Pollutant Transport is the movement of pollutant between air basins or areas within an air 

basin. Transport monitoring is used to assess and mitigate upwind areas when transported 

pollutant affects neighboring downwind areas. Also, transport monitoring is used to 

determine the extent of regional pollutant transport among populated areas and to rural areas.

Population Exposure monitoring is conducted to represent the air pollutant concentrations

that a populated area is exposed to.

Representative Concentration monitoring is conducted to represent the air quality 

concentrations for a pollutant expected to be similar throughout a geographical area. These 

sites do not necessarily indicate the highest concentrations in the area for a particular 

pollutant.

Source Impact monitoring is used to determine the impact of significant sources or source 

categories of air quality emissions on ambient air quality. The air pollutant sources may be 

stationary or mobile.

Trend Analysis monitoring is useful for comparing and analyzing air pollution 

concentrations over time. Usually, trend analyses can be used to assess the progress in 

improving air quality for an area over a period of many years.

Site Comparison monitoring is used to assess the effect on measured pollutant levels of 

moving a monitoring location a short distance (usually less than two miles). Some 

monitoring stations become no longer usable due to development, change of lease terms, or 

eviction. In these cases, attempts are made to conduct concurrent monitoring at the old and 

new site for a period of at least one year in order to compare pollutant concentrations.
Air Quality Monitoring Network Plan – July, 2015

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Real Time Reporting/Modeling is used to provide data to EPA’s AIRNOW system which 

reports conditions for air pollutants on a real time basis to the general public. Data is also 

used to provide accurate and timely air quality forecast guidance to residents of the SCAB.

Multiple purposes for measuring a pollutant at a particular site are possible. There is some overlap 

between site type and monitoring purposes as defined by EPA and given in Tables 2, 3, and 4.

TABLE 1. List of Monitoring Sites

Location AQS No. Pollutants Monitored Start 

Date

1 Anaheim 060590007 CO,NO2,O3,PM10,PM2.5 08/01

2 Anaheim Route 5 Near 

Road2 060590008 CO, NO2 01/14

3 ATSF (Exide) 060371406 Pb 01/99

4 Azusa 060370002 CO,NO2,O3,PM10,PM2.5 01/57

5 Banning Airport 060650012 NO2,O3,PM10, PM2.5 04/97

6 Big Bear 060718001 PM2.5 02/99

7 Burbank1

060371002 CO,NO2,SO2,O3,PM10,PM2.5 10/61

8 Closet World (Quemetco) 060371404 Pb 10/08

9 Compton 060371302 CO,NO2,O3,Pb,PM2.5 01/04

10 Costa Mesa 060591003 CO,NO2,SO2,O3 11/89

11 Crestline 060710005 O3,PM10 10/73

12 Fontana 060712002 CO,NO2,SO2,O3,PM10,PM2.5,SO4 08/81

13 Glendora 060370016 CO,NO2,O3,PM2.5,PM10 08/80

14 Indio 060652002 O3,PM10,PM2.5 01/83

15 La Habra 060595001 CO,NO2,O3 08/60

16 Lake Elsinore 060659001 CO,NO2,O3,PM2.5,PM10 06/87

17 LAX Hastings 060375005 CO,NO2,O3,PM10,Pb,SO4 04/04

18 Long Beach (Hudson) 060374006 CO, NO2,SO2,O3,PM10 01/10

19 Long Beach Route 710 

Near Road2 060374008 NO2, PM2.5 01/15

20 Long Beach (North) 060374002 PM2.5 10/62

21 Long Beach (South) 060374004 PM10,Pb,PM2.5,SO4 06/03

22 Los Angeles (Main St.) 060371103 CO,NO2,SO2,O3,PM10,Pb,PM2.5,SO4 09/79

23 Mira Loma (Van Buren) 060658005 CO,NO2,O3,PM10,PM2.5 11/05

24 Mission Viejo 060592022 CO,O3,PM10,PM2.5 06/99

25 Norco 060650003 PM10 12/80

26 Ontario Fire Station1

060710025 PM10,PM2.5 01/99

27 Ontario Etiwanda Near 

Road2 060710026 CO, NO2 06/14

28 Ontario Route 60 Near 

Road2 060710027 NO2, PM2.5 01/15

29 Palm Springs 060655001 CO,NO2,O3,PM10,PM2.5 04/71

1

Site terminated in 2014.

2 New site in 2014.
Air Quality Monitoring Network Plan – July, 2015

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TABLE 1. (cont) List of Monitoring Sites

Location AQS No. Pollutants Monitored Start 

Date

29 Pasadena 060372005 CO, NO2, O3, PM2.5 04/82

30 Perris 060656001 O3,PM10 05/73

31 Pico Rivera #2 060371602 CO,NO2,O3,Pb,PM2.5,SO4,PM10 09/05

32 Pomona 060371701 CO,NO2,O3 06/65

33 Redlands 060714003 O3,PM10 09/86

34 Rehrig (Exide) 060371405 Pb 11/07

35 Reseda 060371201 CO,NO2,O3,PM2.5 03/65

36 Riverside (Magnolia) 1

060651003 CO,NO2,Pb,PM10,PM2.5,SO4 10/72

37 Rubidoux 060658001 CO,NO2,SO2,O3,PM10,Pb,PM2.5,SO4 09/72

38 San Bernardino 060719004 CO,NO2,O3,PM10,Pb,PM2.5 05/86

39 Santa Clarita 060376012 CO,NO2,O3,PM10,PM2.5 05/01

40 SA Recycling2 Unavailable TSP, Cr6 06/12

41 Saul Martinez 

Elementary2 060652005 PM10, H2S 01/11

42 Temecula 060650016 O3, PM2.5 06/10

43 Uddelholm (Trojan 

Battery) 060371403 Pb 11/92

44 Upland 060711004 CO,NO2,O3,Pb,PM2.5,PM10,SO4 03/73

45 West Los Angeles 060370113 CO,NO2,O3 05/84

1

Site terminated in 2014.

2 New site in 2014.
Air Quality Monitoring Network Plan – July, 2015

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TABLE 2. FRM/FEM Criteria Pollutant Spatial Scales and Site Type

SPATIAL SCALE SITE TYPE

MI – Microscale HC – Highest Concentration

MS – Middle Scale PE – Population Exposure

NS – Neighborhood Scale IM – Source Oriented (Impact)

US – Urban Scale BK – General Background

Location CO NO2 SO2 O3 Manual 

PM10

Manual 

PM2.5

Pb

Anaheim NS/PE US/PE NS/PE NS/PE NS/PE

Anaheim Route 5 Near 

Road2

MI/HC MI/HC

ATSF (Exide) MI/IM

Azusa NS/PE US/PE US/HC NS/PE NS/PE

Banning Airport NS/PE NS/PE NS/PE

Big Bear NS/PE

Burbank 1 NS/HC NS/PE NS/PE US/HC NS/PE NS/PE

Closet World (Quemetco) MI/IM

Compton MS/HC MS/PE NS/PE NS/PE NS/PE

Costa Mesa NS/PE NS/PE NS/PE NS/PE

Crestline NS/HC NS/PE

Fontana NS/PE US/PE NS/PE US/PE NS/HC NS/PE

Glendora NS/PE NS/PE NS/HC

Indio NS/PE NS/HC NS/PE

La Habra NS/PE US/PE NS/PE

Lake Elsinore NS/PE NS/PE NS/PE

LAX Hastings MS/PE/BK MS/PE/BK NS/PE/BK NS/PE/BK NS/PE/BK NS/PE/BK

Long Beach (Hudson) NS/HC NS/PE NS/HC NS/PE NS/PE

Long Beach (North) NS/HC

Long Beach Route 710 Near 

Road2 MI/HC MI/HC

Los Angeles (Main St.) NS/PE NS/HC NS/PE NS/PE NS/PE NS/HC NS/PE

Mira Loma (Van Buren) NS/PE NS/PE NS/PE NS/HC NS/HC

Mission Viejo NS/PE NS/PE NS/PE NS/PE

Norco NS/PE

Ontario Fire Station 1 NS/HC NS/PE

Ontario Etiwanda Near 

Road2

MI/HC MI/HC

Ontario Route 60 Near 

Road2

MI/HC MI/HC

Palm Springs NS/PE NS/PE NS/PE NS/PE NS/PE

Pasadena MS/PE MS/HC NS/PE NS/PE

Perris NS/PE NS/PE

Pico Rivera #2 NS/PE NS/HC NS/HC NS/PE NS/PE

Pomona MI/PE MS/PE NS/HC

Redlands NS/PE NS/PE

Rehrig (Exide) MI/IM

Reseda NS/PE US/PE US/HC NS/PE

Riverside 1 MI/HC US/PE NS/HC MI/HC

Rubidoux NS/PE US/PE NS/PE US/HC NS/HC NS/HC NS/PE

San Bernardino MS/PE US/PE NS/HC NS/HC NS/PE NS/PE

Santa Clarita NS/PE NS/PE US/HC NS/PE

South Long Beach NS/HC NS/HC NS/HC

SA RECYCLING HC/IM

Temecula NS/HC

Uddelholm (Trojan Battery) MI/IM

Upland NS/PE NS/PE NS/PE NS/PE

West Los Angeles NS/PE MS/HC NS/PE

1

Site terminated in 2014.

2 New site in 2014.
Air Quality Monitoring Network Plan – July, 2015

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TABLE 3. FRM/FEM Criteria Pollutant Monitoring Purposes

MONITORING PURPOSE

BK – Background RC – Representative Concentration

HC – High Concentration RM – Real-Time Reporting/Modeling

TP – Pollutant Transport TR – Trend Analysis

EX – Population Exposure CP – Site Comparisons

SO – Source Impact CO - Collocated

Location CO NO2 SO2 O3 Manual 

PM10 

Manual 

PM2.5 Pb

Anaheim TR TR/RC TR TR/RC TR/EX

Anaheim Route 5 Near Road2 SO/HC SO/HC

ATSF (Exide) SO

Azusa TR TR/RC TR TR TR/EX

Banning Airport TP/RC TP TP

Big Bear EX/SO/TP

Closet World (Quemetco) SO

Burbank 1 TR TR/RC TR TR TR/RC TR/EX

Compton TR/HC TR/RC TR/RC EX/RC EX

Costa Mesa RC TR/RC TR RC

Crestline HC TP/RC

Fontana RC TP/RC TR RC HC EX/TP

Glendora RC TR/RC HC

Indio TP HC/CO TP/EX

La Habra RC TR/RC RC

Lake Elsinore TP/RC TP/RC TP/RC

LAX Hastings BK BK BK BK BK BK

Long Beach (Hudson) TR TR/RC TR/HC TR TR/RC

Long Beach (North) EX/HC

Long Beach Route 710 Near 

Road2 SO/HC SO/HC

Los Angeles (Main St.) SO/RC SO/HC TR TR/RC TR/RC/CO EX/HC/CO EX/CO

Mira Loma (Van Buren) TR/RC TR/RC TR/HC HC EX/HC/CO

Mission Viejo RC TR/RC TR/RC EX/RC

Norco TR/RC

Ontario Fire Station 1 HC/CO EX/RC

Ontario Etiwanda Near Road2 SO/HC SO/HC

Ontario Route 60 Near Road2 SO/HC SO/HC

Palm Springs TP/RC TP/RC TP TP/HC EX/TP

Pasadena TR/RC TR/HC TR/RC EX/RC

Perris TP TR

Pico Rivera #2 RC HC HC EX/RC EX

Pomona RC RC HC

Redlands TP/RC TP/RC

Rehrig (Exide) SO/CO

Reseda RC TR/RC HC EX/RC

Riverside 1 HC TR/RC EX/HC EX/CO

Rubidoux TR/RC TR/RC TR TR/HC TR/HC/CO EX/TR/HC/CO EX

San Bernardino TR/RC TP/RC TR/HC TR/HC EX/TR EX

Santa Clarita RC TP/RC TP/HC RC EX/RC

South Long Beach HC EX/SO EX

SA RECYCLING SO/HC

Uddelholm (Trojan Battery) SO

Temecula TR/HC

Upland RC TR/RC TR/RC EX

West Los Angeles RC TR/HC RC

1

Site terminated in 2014.

2 New site in 2014.
Air Quality Monitoring Network Plan – July, 2015

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TABLE 4. Continuous PM10/PM2.5 Monitoring Purpose, Site Type and Spatial Scales

SITE TYPE SPATIAL SCALE INSTRUMENT TYPE

HC – High Concentration MI – Microscale TEOM 

PE – Population Exposure NS – Neighborhood Scale BAM (NON-FEM)

BK - Background BAM (FEM)

MONITORING PURPOSE

SO – Source Impact RM – Real-Time Reporting/Modeling

TP – Pollutant Transport SPM – Special Purpose Monitoring

TR – Trend Analysis CO - Collocated

Location Continuous PM10 Continuous PM2.5 PM10 – 2.5

Type Purpose Site 

Type Scale Type Purpose Site Type Scale Operational

Anaheim BAM/FEM RM/TR PE NS BAM/FEM RM/TR PE NS

Banning 

Airport BAM/NON-FEM RM PE NS

Burbank1 TEOM/FEM RM/TR PE NS BAM/FEM RM/TR PE NS

Crestline BAM/NON-FEM RM PE NS

Glendora BAM/FEM RM PE NS BAM/NON-FEM RM PE NS

Indio TEOM/FEM RM HC NS

Lake Elsinore TEOM/FEM RM PE NS BAM/NON-FEM RM PE NS

Long Beach 

Route 710 Near 

Road2

BAM/FEM RM/SO

Los Angeles

(Main St.) BAM/FEM RM/TR PE NS BAM/FEM RM HC NS Yes

Mira Loma 

(Van Buren) BAM/FEM RM HC NS BAM/FEM RM HC NS

Ontario Route 60 

Near Road2 BAM/FEM RM/SO

Palm Springs TEOM/FEM RM/TP HC NS

Reseda BAM/NON-FEM RM PE NS

Riverside1 BAM/FEM RM HC NS BAM/NON-FEM RM HC NS

Rubidoux TEOM/FEM RM/TR HC NS BAM/FEM & 

NON-FEM RM/TR/CO HC NS Yes

San 

Bernardino TEOM/FEM RM/TR HC NS

Santa Clarita BAM/NON-FEM RM PE NS

Saul Martinez 

Elementary TEOM/FEM RM/CO PE NS

South Long 

Beach BAM/FEM RM/SO PE NS

Temecula BAM/NON-FEM RM PE NS

Upland BAM/FEM RM PE NS BAM/NON-FEM RM PE NS

1

Site terminated in 2014.

2 New site in 2014.
Air Quality Monitoring Network Plan – July, 2015

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A brief description of the criteria pollutant and program monitoring networks are provided below:

OZONE (O3)

The SCAQMD operates 29 sites where O3 measurements are made as part of the Air 

Monitoring Network. O3 sites are spread throughout the SCAB with highest concentrations 

measured inland. Figure 1 in Appendix A shows the spatial distribution of these sites and 

Table 16 shows the minimum monitoring requirements.

PM10

Size-selective inlet manual high volume samplers are operated at 19 sites to meet the 

requirements for PM10 Federal Reference Method (FRM) sampling. The PM10 monitoring 

network contains five sites within 25% of the Federal NAAQS as shown in the 2014 Air 

Quality Data Table (http://www.aqmd.gov/home/library/air-quality-data-studies/historicaldata-by-year), Figure 9. The Indio, Mira Loma and Rubidoux sites are designated PM10 

collocated and shown in Table 24. All PM10 FRM monitors operate on a one day in six 

day schedule, with the exception of Indio, Mira Loma and Rubidoux which operate on one 

day in three day schedule. The Anaheim and Mira Loma sites are shown as expected

maximum value sites by MSA in Table 18. Consequently, as expected maximum 

concentration sites, Mira Loma and Anaheim meet the minimum sampling schedule 

requirement shown in 40 CFR §58.12 . The remaining sites meet or exceed the minimum 6 

day sample schedule requirement.

PM10 continuous analyzers are operated at 10 sampling sites. These real-time devices are 

capable of making hourly particulate concentration measurements. Table 4 describes the 

monitor type, site type, monitoring purpose, and spatial scale for continuous particulate 

analyzers. Figure 2 in Appendix A shows the spatial distribution of the sampling sites and 

Table 18 shows the minimum monitoring requirements. Real-time monitors, for the most 

part, are clustered in the high concentration areas, with two located in the desert area where 

wind-blown crustal material has caused exceedances of the twenty-four hour standard during 

exceptional events. In downwind areas of the SCAB, a large fraction of particulate is formed 

in the atmosphere; PM10 reaches maximum levels during late summer through early winter 

months. 

Where both 24 hour PM10 FRM samplers and PM10 FEM continuous analyzers are 

deployed together, they are sited as collocated for data comparison purposes where possible. 

The 24 hour FRM PM10 sampler remains the primary analyzer used for attainment purposes.

PM10-2.5

PM10-2.5 (PM Coarse) is required at NCore sites only and is derived from the continuous 

BAM PM10 and PM2.5 particulate monitors at those sites. The Purpose, Site Type and 

Scale are similar to the continuous PM10 and PM2.5 instruments from which data is 

calculated. PM Coarse is currently measured at the Los Angeles (Main St.) and Rubidoux 

sites and is shown in Table 4.
Air Quality Monitoring Network Plan – July, 2015

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NITROGEN DIOXIDE (NO2)

The area wide NO2 network consists of 23 sites. These sites are mostly located in areas of 

highest expected NO2 concentrations. The Near Road monitoring network consists of four

sites which were implemented in January of 2014 and 2015. These sites are located adjacent 

to the most heavily traveled roadways identified in the basin. The spatial distribution of 

NO2 monitors is shown in Figure 3 in Appendix A and minimum monitoring requirements 

are shown in Table 19. Additionally, the Regional Administrator identified 40 NO2 sites 

nationwide with a primary focus on siting these monitors in locations to protect susceptible 

and vulnerable populations. The Regional Administrator in collaboration with SCAQMD 

indentified the Los Angeles (Main), Long Beach (North) and San Bernardino sites from the 

existing area-wide monitoring network to meet this requirement (58.10[a][5]). On 

September 30, 2013, the continuous monitors including NO2 were discontinued at Long 

Beach (North) due to termination of the lease by owner. SCAQMD is proposing redesignation of Compton as a RA 40 site and is discussed further in Appendix D. SCAQMD 

is in the process of identifying a replacement monitoring location for Long Beach (North) in 

collaboration with Long Beach Department of Public Health and also considering potential 

consolidation with nearby sites. Review of 1992 through 2012 NO2 data shows the State and 

Federal standards for NO2 were not exceeded.

CARBON MONOXIDE (CO)

Area wide CO monitors measure concentrations at 23 locations, and 2 near road monitors 

operate within the SCAQMD ambient air monitoring network. Figure 4 in Appendix A

shows the spatial distribution of these sites. CO emissions, primarily from motor vehicles, 

show a pattern consistent with major freeway arteries. A review of data for 2013 shows

State and Federal standards for CO were not exceeded.

SULFUR DIOXIDE (SO2)

SO2 monitors are located at 6 sites. Figure 5 in Appendix A shows the spatial distribution 

of the sites. Most SO2 emissions come from Federal transportation sources such as marine 

vessels. The monitors are clustered mostly in the areas where these sources are located. 

On June 22, 2010 EPA strengthened the SO2 National Ambient Air Quality Standard 

(NAAQS). Network design requirements included new minimum requirements be 

determined by the Population Weighted Emissions Index (PWEI).

The PWEI shall be calculated by States for each CBSA they contain or share with 

another State or States for use in the implementation of or adjustment to the SO2

monitoring network. The PWEI shall be calculated by multiplying the population 

of each CBSA, using the most current census data or estimates, and the total amount 

of SO2 in tons per year emitted within the CBSA area, using an aggregate of the 

most recent county level emissions data available in the National Emissions 

Inventory (NEI) for each county in each CBSA. The resulting product shall be 

divided by one million, providing a PWEI value, the units of which are million 

persons-tons per year. For any CBSA with a calculated PWEI value equal to or 

greater than 1,000,000, a minimum of three SO2 monitors are required within that 

CBSA. For any CBSA with a calculated PWEI value equal to or greater than 
Air Quality Monitoring Network Plan – July, 2015

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100,000, but less than 1,000,000, a minimum of two SO2 monitors are required 

within that CBSA and for any CBSA with a calculated PWEI value equal to or 

greater than 5,000, but less than 100,000, a minimum of one SO2 monitor is 

required within that CBSA.

TABLE 5. PWEI Calculation and Minimum Required SO2

SCAQMD exceeds the minimum requirement for SO2 monitors; the Federal standard has 

not been exceeded for nearly 33 years.

PARTICULATE LEAD

Total Suspected Particulate (TSP) Pb measurements are collected at 12 sites as part of the 

particulate network; 4 of the sites are Source Impact for Pb, and the remaining 8 sites 

measure ambient Pb.

In 1990, the EPA requested that the SCAQMD collect ambient air particulate samples near 

several large Pb handling (battery recycling) facilities. Long-term source impacted 

monitoring began in 1991. A facility in the City of Industry exceeded the Federal ambient 

particulate Pb standard during the second quarter of Fiscal Year 1991-92. Pb monitoring at 

a facility in the City of Torrance ended in 1993 when measurements were consistently below 

the ambient standard. Sampling ended at a facility in the City of Commerce in 2006 when 

the business was closed. Out of the facilities currently being monitored, the facility in the 

City of Vernon exceeded the old Federal ambient particulate Pb standard (1.5 ug/m3 

quarterly) during the first quarter of 2008; the other facility was found to remain below this 

level. 

The Rehrig (Exide) microscale site typically measures the highest Pb concentrations in the 

monitoring network. A notice of violation issued was on April 23, 2014 for, “Discharging 

into the atmosphere lead emissions exceeding 0.150 μg/m3 averaged over 30 days”. On 

March 11, 2015, Exide agreed to immediately and permanently close the Vernon site in an 

agreement with the assistant U.S. attorney and chief of environmental crimes. 

Monitoring continues at the site and it has been designated as a collocated monitoring 

location for the source oriented Pb monitoring network. The Los Angeles, and Compton 

sites are designated as collocated for the area wide Pb monitoring network; collocation 

requirements are shown in Table 24. During 2014 the Riverside site was designated as a 

collocated site for Pb but on 3/17/15 the lease was not renewed due to safety considerations. 

Since that time, the Compton site has been re-designated as a collocated site for Pb. The 

SCAQMD continues to exceed the minimum monitoring requirements with the closure of 

the Riverside monitoring site. The spatial distribution of these sites is shown in Figure 6 in 

Appendix A.

CBSA Population Estimate NEI SO2 Emmissions PWEI Value Minimum Required SO2 

31080 13,131,431 6,102.45 80,134 1

40140 4,380,878 2,307.02 10,107 1
Air Quality Monitoring Network Plan – July, 2015

11

On November 12, 2008, the EPA issued final revisions to the NAAQS for Pb. Network 

design requirements included monitoring for sources of Pb (source oriented monitoring) and 

urban Pb monitoring (non-source oriented). To meet this requirement, a source oriented site 

was established on January 1, 2010 at the Van Nuys Airport and monitoring continues at the 

sites surrounding the Exide (Vernon), Quemetco (Industry), and the Trojan Battery facilities. 

Existing urban Pb monitoring conducted at Compton, LAX Hastings, Los Angeles (Main), 

Pico Rivera, Riverside Magnolia, Rubidoux, San Bernardino, South Long Beach, and 

Upland exceed the minimum monitoring requirements. 

The final rule for Pb went into effect on January 26, 2011. In the final rule the Van Nuys 

Airport was no longer included on the list of airports where Pb monitoring was required, and 

a more recent emissions inventory showed Pb emissions less than the minimum monitoring 

requirement of 1.0 ton per year. The landowner advised SCAQMD the lease would not be 

renewed at the end of the three year contract period. Data review from the Van Nuys Airport 

Pb site showed no exceedances of the three month rolling average during the monitoring 

period. In consultation EPA the site was discontinued on June 4, 2013 based upon conditions 

cited in 40 CFR 58 Appendix D 4.5. 

The most recent NEI data (2011) as of 5/1/2015 shows no sites exceed the 1.0 tpy 

requirement http://www.epa.gov/ttnchie1/net/2011inventory.html) threshold requiring a 

monitoring plan:

 

TPY State County Facility

0.8 CA Los Angeles LONG BEACH-DAUGHERTY 

FIELD AIRPORT

0.68 CA Los Angeles VAN NUYS AIRPORT

0.58 CA Orange JOHN WAYNE AIRPORT

0.58 CA San Bernardino CHINO AIRPORT

Photochemical Assessment Monitoring Stations

The Photochemical Assessment Monitoring Stations (PAMS) network was initiated in June 

1994 at Pico Rivera and Upland. During 1995 sites were established at Banning and Azusa

to determine speciated hydrocarbon O3 precursor compounds in ambient air. PAMS 

monitoring at Hawthorne commenced in June 1997 and the Burbank station became a PAMS 

site in July 1997. In May 2001, the Santa Clarita location was established as a PAMS site. 

In April 2004, the Hawthorne site was replaced by LAX Hastings, due to the end of a 

property lease. In August 2005, the Pico Rivera station moved to a new location one half 

mile south of the previous site, also due to the end of the property lease.

On October 17, 2006, the EPA issued final amendments to PAMS monitoring requirements 

in 40 CFR § 58. The changes made to the rule were to implement recommendations made 

by the PAMS workgroup formed to assess the program. The workgroup recommended 

changes be made to site type and monitoring objectives. During September 2008, a report 

from the EPA PAMS network assessment project workgroup was issued. The objectives of 

the workgroup were to assess how well the current PAMS network was meeting monitoring 

objectives, determine which sites are most useful for meeting objectives, identify potentially 
Air Quality Monitoring Network Plan – July, 2015

12

redundant, ineffective, or unnecessary sites, and to assess other enhanced O3 monitoring 

activities that may prove useful.

Site Types are defined as:

 Type 1 sites are established to characterize upwind background and transported O3 and 

its precursor concentrations entering the area and will identify those areas which are 

subjected to transport.

 Type 2 sites are established to monitor the magnitude and type of precursor emissions 

in the area where maximum precursor emissions are expected to impact and are suited 

for the monitoring of urban air toxic pollutants.

 Type 3 sites are intended to monitor maximum O3 concentrations occurring downwind 

from the area of maximum precursor emissions.

 Type 4 sites are established to characterize the downwind transported O3 and its 

precursor concentrations exiting the area and will identify those areas which are 

potentially contributing to overwhelming transport in other areas.

To address regulatory changes, site-specific observations from the PAMS network 

assessment project, and potential synergies between programs, SCAQMD made the 

following changes in June 2009 to the PAMS monitoring network:

 Burbank was reclassified from Type 2/1 to Type 2. This change addressed the National 

PAMS Network Assessment observation that Burbank should be reclassified to a Type 

2 precursor site. The recommendation is consistent with the heavily 

urbanized/industrialized area, which is impacted by high levels of O3 precursor 

emissions. 

 Santa Clarita was reclassified as Type 3 from Type 2. Although the National PAMS 

Network Assessment observed that Santa Clarita was consistent with a Type 2 site, 

recent data was more consistent with a Type 3 maximum O3 concentration site rather 

than a Type 2 O3 precursor site.

 Banning was relocated to Los Angeles (Main). The National PAMS Network 

Assessment observed that Banning had the lowest O3 concentrations of all the Type 2 

sites and should be reclassified to a Type 3 or 4 site. Instead, to create synergies 

between programs, SCAQMD relocated the Banning PAMS site to the Los Angeles 

(Main) site as Type 2. This satisfies the EPA recommendation for use of the same 

monitoring platform and equipment to meet the objectives of multiple programs. Los 

Angeles (Main) is also a National Air Toxics Trends Station (NATTS), a 

National Core-Multi-pollutant Monitoring Station (NCore), and a Speciation Trends 

Network (STN) site.

 Azusa was reclassified from Type 3 to Type 2. This proposed change addresses the 

National PAMS Network Assessment observation that Azusa has high Volatile Organic 

Compounds (VOC) and Oxides of Nitrogen (NOX) concentrations, with lower O3 

concentrations. The site now more closely resembles a Type 2 O3 precursor site.

 Upland was relocated to the Rubidoux site. The National PAMS Network Assessment 

observed that Upland was no longer consistent with a Type 4 site and recommended 

reclassification to Type 3. SCAQMD relocated the Upland PAMS site to Rubidoux as 
Air Quality Monitoring Network Plan – July, 2015

13

a Type 3 location where synergies can be created among the NATTS, NCore, and the 

STN programs.

 LAX Hastings and Pico Rivera remained unchanged.

Currently, manual VOC canisters are in operation at the Azusa, LAX Hastings, Rubidoux, 

Los Angeles (Main), and Santa Clarita air monitoring stations. Under this program, during 

the intensive season from July 1 until September 30, VOC canisters were run every three 

hours for a period of twenty-four hours every 3rd day and a twenty-four hour sample is run 

every 6th day. During the non-intensive season from October 1 through June 30, twentyfour hour VOC canister samples were run every 6th day.

SCAQMD upper air meteorological monitoring stations are established at Los Angeles 

International Airport (LAX), Ontario International Airport (ONT), Moreno Valley (MOV) 

at the Moreno Valley Municipal Water Treatment Plant in Riverside County, Irvine (IRV) 

at the University of California Research and Extension Center, and Pacoima at Whiteman 

Airport (WHP). The upper air stations use a combination of remote sensing and surface 

meteorological instrumentation, including the Scintec (formerly Radian/URS and 

Vaisala) LAP-3000 radar wind profiler with a Radio Acoustic Sounding System (RASS), 

the Atmospheric Systems Corporation (formerly AeroVironment Inc.) mini Sodar acoustic 

wind profiler, and tower-mounted meteorological measurements of wind, pressure, 

temperature, relative humidity, solar radiation, and ultraviolet radiation. Due to the age of 

the LAX upper air instrumentation and costly component failures, SCAQMD has replaced 

the LAX radar wind profiler instrumentation with that from Whiteman Airport. Surface 

meteorology and mini-Sodar instruments are still operational at the Whiteman Airport upper 

air station.

During April 2013, a system audit was conducted by the EPA, which assessed the SCAQMD 

NATTS/PAMS programs. The audit found no major issues with the operation of the 

network.

On November 25, 2014, the EPA proposed to strengthen the National Ambient Air Quality 

Standards (NAAQS) for ground-level ozone, based on extensive scientific evidence about 

ozone's effects. Proposed changes to the rule include PAMS monitoring requirements in 40 

CFR § 58 which includes recommendations made by the PAMS national working group. 

Proposed changes include (Cavendar, U.S. EPA, 2015):

– Reduce number of required sites to 1 per area but expand PAMS applicability to all 

O3 non-attainment areas

– Require PAMS at NCore sites in O3 non-attainment areas but allow for Regional 

approval of alternative site (e.g., existing type 2 PAMS sites) 

– Require sites to collect hourly VOC data

– Require sites to collect carbonyls (formaldehyde, etc.)

– Require sites to measure “true NO2” in addition to current NOy

– Change requirement for upper air meteorology to requirement for measuring 

mixing height
Air Quality Monitoring Network Plan – July, 2015

14

The proposed rule closed for comment and the final form of the rule is expected to be 

released later in 2015.

Although SCAQMD has used the PAMS data for trends analysis, trajectory modeling, and 

source emissions inventory reconciliation, SCAQMD has conducted an assessment of its 

PAMS program. The assessment indicated that although the existing program provides a 

robust data set, the measurement program can be modernized to compliment current and 

future U.S. EPA program requirements, strengthening the connection between the PAMS 

measurements objectives to better comprehension of ozone in the South Coast Basin. Thus, 

in the next two years, SCAQMD will focus its resources on optimizing the program, 

evaluating technologies, and shifting resources to prepare for the revised program. The 

general concept will be to conduct intensive one-year large scale Specialized PAMS 

(SPAMS) measurements every several years and in between SPAMS, conduct reduced core 

PAMS program during non-intensive years. 

During non intensive years the goal is to track Annual statistics, trends (yearly, seasonally, 

monthly, weekly, daily, hourly), spatial distribution, comparison to other federal programs, 

and comparison data for special projects. Non intensive monitoring is proposed at four sites:

 Los Angeles (Main street): Proposed required by U.S. EPA, Station Leveraging, 

Current Type 2 site

 Azusa: Current Type 2 site, Trend site

 Rubidoux: Proposed required by U.S. EPA, Station leveraging, Current Type 3 site.

 Long Beach: Port/ Refineries activity and emissions

During the periodic intensive one year SPAMS intensive period, the goal is to conduct 

measurements with better spatial resolution (both vertical and horizontal), establish trend 

data (yearly, seasonally, monthly, weekly, daily, hourly) – develop control strategies, 

emissions inventory evaluations, local scale studies, full scale photochemical transport 

modeling, VOC/NOx profiling, and background characterization. Intensive years would 

take place on Air Quality Management Plan (AQMP) years. More detail on the SPAMS 

program will be provided in next year's annual network plan.

The 2015 PAMS network monitoring objectives and requirements are summarized in Table 

6 and Table 23 Figure 7 in Appendix A which shows the distribution of the PAMS network. 

Starting July 1, 2015 SCAQMD will not conduct the intensive season sampling schedule for 

PAMS sites but will continue the current non intensive schedule for all current PAMS sites. 

During this non-intensive season twenty-four hour VOC canister samples are run every 6th 

day and twenty-four hour carbonyl samples are run every 6th day. Rubidoux is a collocated 

site for VOC canister sampling and Pico Rivera is a collocated site for VOC canister and 

carbonyl sampling. Instead, SCAQMD will be evaluating implementation options for the 

revised PAMS/ SPAMS programs by participating in the U.S. EPA PAMS GC assessment, 

upgrading its air monitoring network infrastructure, preparing mobile platforms, and 

evaluating instruments and methods. 
Air Quality Monitoring Network Plan – July, 2015

15

TABLE 6. PAMS Network

January 1 to December 31

Site 

Type

Date 

Established as 

PAMS

Site / AQS ID# VOC Carbonyl Additional Requirements

1 04/01/2004

LAX Hastings 

(replaced 

Hawthorne)

1 x 24 hr sample every 6th

day No Sampling

2 06/01/1995 Azusa 1 x 24 hr sample every 6th

day No Sampling No/NOx required

2 07/01/1997 Burbank 1 x 24 hr sample every 6th

day

1 x 24 hr sample every 

6

th day

2 06/01/2009 Los Angeles (Main) 1 x 24 hr sample every 6th

day

1 x 24 hr sample every 

6

th day

Trace level CO required at one type 2 

site.

2 08/01/2005 Pico Rivera #2 1 x 24 hr sample every 6th

day

1 x 24 hr sample every 

6

th day

3 06/09/2009 Rubidoux 1 x 24 hr sample every 6th

day No Sampling NOy required

3 05/01/2001 Santa Clarita 1 x 24 hr sample every 6th

day

1 x 24 hr sample every 

6

th day

MONITORING OBJECTIVES: MONITORING REQUIREMENTS: REDUCED REQUIREMENTS:

1 – Upwind and background characterization site One type 1 or type 3 site required per area Speciated VOC only required at type 2 and one other 

(type 1 or 3)

2 – Maximum O3 precursor emissions impact site One type 2 site required per area Carbonyl only required in areas classified as serious 

or above 8 hr zone

3 – Maximum O3 concentration site No type 4 required NO/NOx required only at type 2

4 – Extreme downwind monitoring site NOy required at one site per PAMS area (type 1 or 3)
Air Quality Monitoring Network Plan – July, 2015

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PM2.5

A network of 17 FRM samplers was first implemented in January 1999. On December 26, 

1999, a second Coachella Valley PM2.5 sampling site was established in Palm Springs. On 

June 20, 2003, PM2.5 sampling began at the South Long Beach site. The Mira Loma site 

was added during October, 2005 and the Route 710 Long Beach and Route 60 Ontario near 

road sites were added during January, 2015. During 2014 the Riverside, Burbank, and 

Ontario sites were discontinued due to termination of leases, This brings the total number 

of PM2.5 FRM sampling sites to 19. The sites are depicted in Figure 8, Appendix A and the 

starting date of each sampler is listed in Table 7. In March 2012, a change was made 

relocating the collocated PM2.5 monitor from Indio to the Mira Loma (Van Buren) site. 

This change was made following approval from EPA. Collocated sampling sites include 

Rubidoux, Central Los Angeles, and Mira Loma (Van Buren). Of the collocated sites, all 

three are located at sites which have exceeded Federal NAAQS as shown in Figure 9, and 

Appendix A, 2013 Air Quality Data Table. The latest data can be found at: 

(http://www.aqmd.gov/home/library/air-quality-data-studies/historical-data-by-year).

Manual PM2.5 monitors are sited as neighborhood scale and population exposure 

representing community wide air quality with multiple sites are listed as population 

exposure. Because all of SCAQMD is in non-attainment for PM2.5, most of the sites are in 

areas of poor air quality therefore multiple sites are listed as population exposure and high 

concentration. If a PM2.5 network modification were to be implemented for a site that was 

in exceedence of the PM2.5 NAAQS levels, SCAQMD would notify U.S. EPA Region IX 

via written communication. Public notice of network modifications occurs as part of the 

annual network plan process which is stated in the annual network plan. All sites in the 

Network using FRM samplers are suitable for comparison against the annual PM2.5 

NAAQS. 

During April 2009, SCAQMD completed minor changes to the FRM monitoring schedule 

to enhance Federal Equivalent Method (FEM) Beta Attenuation Monitor (BAM)

comparisons. On April, 16th, 2009 the Burbank and Mira Loma (Van Buren) FRM samplers 

changed to daily sampling from the 1-in-3 day schedule and the Azusa location changed 

from every day sampling to 1-in-3 day sampling. Daily design value sites are shown in 

Table 17a as the Los Angeles and Mira Loma sites. A replacement site is currently being 

sought for Burbank due to termination of lease and the Mira Loma site meets the minimum 

daily monitoring requirement. Monitors exceed the minimum NCore 1 in 3 requirements at 

the Rubidoux and Los Angeles (Main) sites. The remaining sites adhere to the 1 in 3 

schedule with the exception of Big Bear which was approved at the inception of the PM2.5 

program as a 1 in 6 site. The Federal minimum monitoring requirements for PM2.5 are 

being met and/or exceeded by the SCAQMD PM2.5 monitoring network.

Continuous PM2.5 Met One BAMs were first deployed in fiscal year 2001–02. Fifteen

monitors are now operating in the SCAB, two at Rubidoux (FEM & Non FEM BAM), and 

one each at Anaheim, Los Angeles, South Long Beach, Mira Loma (Van Buren), and 

Banning sites. In January 2006, two additional samplers were added at Lake Elsinore and 

Glendora as part of the Children’s Health Study. As proposed in the 2008 network plan, 

FEM BAM monitors were deployed during October 2008, at the Anaheim, Burbank, Los 
Air Quality Monitoring Network Plan – July, 2015

17

Angeles (Main), Mira Loma (Van Buren), Rubidoux, and South Long Beach sites. 

Relocated NON-FEM BAM samplers were installed at Reseda, Riverside Magnolia, Santa 

Clarita, Crestline, and Upland. A NON-FEM BAM was collocated with a FEM BAM at 

Rubidoux. An additional NON-FEM BAM sampler was deployed at Temecula during July, 

2010. In 2011, all FEM BAMs have been reclassified from special purpose monitors to 

SLAMS under 40 CFR § 58.20. During 2014 the Burbank and North Long Beach sites were 

discontinued due to termination of leases. 

In 2014, SCAQMD conducted a PM2.5 Continuous Monitor Comparability Assessment in 

accordance with the PM NAAQS rule published on January 15th, 2013 (78 FR 3086). 

Specific to the provisions detailed in §58.10 (b)(13) and §58.11 (e), the assessment results 

indicate that all of the SCAQMD PM2.5 Continuous Monitors do not meet the criteria to be 

compared against the NAAQS. Thus, SCAQMD requested a waiver to exclude PM2.5 

continuous monitor data from NAAQS comparison. Meanwhile, SCAQMD is conducting 

comparison studies of newer technology to determine their ability to meet the criteria to be 

compared against the NAAQS. At such time when the assessment indicates that the FEM 

monitors are within the acceptance criteria, then U.S. EPA will be notified of the results and 

the AQS parameters will be changed to indicate that the data will be eligible for comparison 

to the NAAQS upon U.S. EPA approval. 

Coarse particulate matter measurements (PM10-2.5) are required at NCore sites. To meet 

this requirement SCAQMD measures this value utilizing the continuous BAM monitors at 

the Los Angeles (Main) and Rubidoux air monitoring sites. These monitors are shown in 

Table 4. 

Where both 24 hour FRM PM2.5 samplers and FEM PM2.5 continuous analyzers are 

deployed together, they are sited as collocated for data comparison purposes if the FEM 

analyzer meets the acceptance criteria under 78 FR 3086. 
Air Quality Monitoring Network Plan – July, 2015

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TABLE 7. Manual PM2.5 FRM Monitoring Stations Assigned Site Numbers

Location Site Code ARB No. AQS No. Start Date Schedule

Anaheim ANAH 30178 060590007 01/03/99 Daily

Azusa AZUS 70060 060370002 01/04/99 1-in-3

Big Bear BGBR 36001 060718001 02/08/99 1-in-6

Burbank1 BURK 70069 060371002 Closed

Compton COMP 70112 060371302 11/08 1-in-3

Fontana FONT 36197 060712002 01/03/99 1-in-3

Indio INDI 33157 060652002 01/30/99 1-in-3

Long Beach (North) LGBH 70072 060374002 01/03/99 Daily

Long Beach Route 710 Near 

Road2 W710 70032 060374008 01/01/15 Daily

Los Angeles “A” (Main St.) CELA 70087 060371103 01/03/99 Daily

Los Angeles “B” (Main St.) CELA 70087 060371103 01/06/99 1-in-6

Mira Loma (Van Buren) “A” MRLM 33165 060658005 11/09/05 Daily

Mira Loma (Van Buren) “B” MRLM 33165 060658005 03/08/12 1-in-6

Mission Viejo MSVJ 30002 060592022 06/15/99 1-in-3

Ontario Fire Station1 ONFS 36025 060710025 Closed

Ontario Route 60 Near Road2

60NR 36036 060710027 01/01/15 Daily

Palm Springs PLSP 33137 060655001 12/26/99 1-in-3

Pasadena PASA 70088 060372005 03/04/99 1-in-3

Pico Rivera #2 PICO 70185 060371602 09/12/05 1-in-3

Reseda RESE 70074 060371201 01/24/99 1-in-3

Riverside1 RIVM 33146 060651003 Closed

Rubidoux “A” RIVR 33144 060658001 01/03/99 Daily

Rubidoux “B” RIVR 33144 060658001 01/03/99 1-in-6

San Bernardino SNBO 36203 060719004 01/03/99 1-in-3

South Long Beach SLGB 70110 060374004 06/20/03 Daily

1 Closed in 2014.

2 New in 2014

FRM PM2.5 sampler remains the primary analyzer used for attainment purposes and 

continuous analyzers are designated as audit samplers unless the primary 24 hour FRM 

PM2.5 is offline then continuous FEM analyzer data can be substituted if the FEM analyzer 

meets the acceptance criteria under 78 FR 3086. 

PM2.5 speciation sampling is also a part of the SCAQMD PM2.5 program. Collocated STN

Met One SASS PM2.5 and one SCAQMD Met One SASS PM2.5 speciation samplers were 

deployed in March 2001 at Rubidoux. An additional STN Met One SASS and collocated

SCAQMD SASS samplers were deployed at Central Los Angeles in 2002. In 2003, 

SCAQMD SASS PM2.5 speciation samplers were installed at Fontana and Anaheim air 

monitoring sites. Analysis of the filters from the SCAQMD ambient network SASS 

samplers are being conducted at SCAQMD’s laboratory. The STN SASS sample filters are 

shipped to Research Triangle Institute (RTI) for analysis. This approach has the concurrence 

of CARB and EPA, Region IX.
Air Quality Monitoring Network Plan – July, 2015

19

National Air Toxics Trends Station (NATTS)

The NATTS program was developed to fulfill the need for long-term Hazardous Air 

Pollutant (HAP) monitoring data of consistent quality nationwide. SCAQMD has conducted 

several air toxics measurement campaigns in the past, which demonstrated the variety and 

spatial distribution of air toxics sources across SCAB. A single air toxics measurement site 

cannot reflect the levels and trends of air toxics throughout the SCAB. For this reason, two 

NATTS sites are used to characterize the SCAB’s air toxics levels. The first site is a central 

urban core site in Los Angeles that reflects concentrations and trends due primarily to urban 

mobile source emissions. A second, more rural, inland site at Rubidoux captures the 

transport of pollutants from a variety of upwind mobile and industrial sources in the most 

populated areas of the air basin. NATTS monitoring began in February 2007 and continues 

at the Los Angeles (Main) and Rubidoux air monitoring sites. During April 2013, a system 

audit was conducted by the EPA, which assessed the SCAQMD NATTS program. The audit 

found no major issues with the operation of the network. 

NCore

NCore monitoring rules required that SCAQMD make NCore sites operational by January 

1

st, 2011. To meet this goal, SCAQMD installed trace level analyzers for CO, NOY and 

SO2 at the Rubidoux and Central Los Angeles sites. Continuous PM10 and PM2.5 BAM 

are utilized for PM10-PM2.5 measurements at both sites. Final calibrations were completed 

at the Rubidoux site January, 2011 and at the Central Los Angeles during May, 2011. Both 

the Los Angeles and Rubidoux sites are NATTS and PAMS monitoring locations.

Special Programs

Special monitoring programs are conducted for rule compliance purposes, to characterize the 

levels of toxic air contaminants and other criteria pollutants in sub-regional areas or communities 

in the SCAB, or to support modeling and planning efforts. The following is a list of special 

monitoring programs that were active during the past year. Note that this is being provided for 

informational purposes only. 

MATES IV

The SCAB is a highly urbanized area home to about seventeen million people who own and 

operate about eleven million motor vehicles, and contains some of the highest concentrations 

of industrial and commercial operations in the country. In 1986, SCAQMD conducted the 

first MATES study to determine the SCAB-wide risks associated with major airborne 

carcinogens. At the time, the state of technology was such that only ten known air toxic 

compounds could be analyzed. In 1998, a second MATES study (MATES II) was 

conducted; MATES II included a monitoring program of 40 known air toxic compounds, an 

updated emissions inventory of toxic air contaminants, and a modeling effort to characterize 

health risks from hazardous air pollutants. In April 2004, the SCAQMD conducted the third 

MATES study (MATES III) to assess the ambient levels of airborne compounds linked to 

adverse health effects in humans. And in June, 2012 SCAQMD began the MATES IV study 

and concluded in June, 2013. A draft final report was issued during 2014

(http://www.aqmd.gov/home/library/air-quality-data-studies/health-studies/mates-iv) for 

public comment, and the final report has been released May 1, 2015.
Air Quality Monitoring Network Plan – July, 2015

20

The MATES IV Study included a monitoring program, an updated emissions inventory of 

toxic air contaminants, and a modeling effort to characterize risk across the Basin. The local 

scale component of the study continued to focus on the carcinogenic risk from exposure to 

air toxics but will not estimate mortality or other health effects from particulate exposures. A 

focus of MATES IV is the inclusion of measurements of ultrafine particle concentrations. In 

addition, shorter-term measurements are being conducted at various locations to assess 

localized impacts of combustion sources. The focus of these measurements were on 

assessing the exposures to ultrafine particles and black carbon very near sources such as 

airports, freeways, rail yards, busy intersections, and warehouse operations.

The goal of MATES IV was to enhance the spatial resolution of previous studies by 

characterizing the ambient concentration of selected toxic air compounds in communities 

with varying land-type usage, such as residential, industrial, and commercial, as well as 

gradients from source areas downwind to receptor areas.

For trend analysis the MATES IV study utilized the same ten fixed monitoring sites used in 

the MATES III study. These monitoring locations are the Anaheim, Burbank, Compton, 

Fontana, Huntington Park, North Long Beach, LA Main Street, Pico Rivera, Rubidoux, and 

West Long Beach monitoring sites. As of June 2013 monitoring at these ten fixed sites has 

been completed. MATES IV added Ultra Fine Particulate (UFP) and Black Carbon (BC) 

continuous measurements.

The Local Scale component to the MATES IV study utilizes mobile monitoring platforms 

deployed for short term measurements of selected compounds near sources such as airports, 

freeways, rail yards, busy intersections, and warehouse operations.

Fugitive Dust Study

In support of SCAQMD Rule 403 - Fugitive Dust, SSI PM10 samplers are deployed on an 

episodic basis upwind and downwind of potential sources as required under Rule 403. Since 

2003, periodic sampling has been conducted around gravel quarries and other industries 

which seem to be producing large volumes of dust. 

Hexavalent Chrome 

The SCAQMD has an ongoing program to collect ambient hexavalent chromium samples in 

the vicinity of several chrome plating and cement production facilities located throughout 

the SCAB. Monitoring continues at Newport Beach, Riverside, and other locations 

throughout the SCAQMD jurisdiction.

GERDAU-TAMCO

GERDAU North America acquired the TAMCO Rancho Cucamonga steel mini mill in 

October, 2010. In 2012 an environmental audit was conducted at the facility and found 

discrepancies in reported emissions with respect to SOx and NOx. Further, it was suspected 

that Pb emissions can contribute to an exceedence of the NAAQS. SCAQMD conducted 

inspections of the facility to address issues and continues monitoring for Pb, Cr+6, and other 

metals at the facility. Monitoring efforts at TAMCO currently measure Pb, Total Metals and 

Cr+6 on a 3 day schedule.
Air Quality Monitoring Network Plan – July, 2015

21

Salton Sea Monitoring

On Sunday September 9, 2012, a strong thunderstorm over the Salton Sea caused odors to 

be released and transported to the northwest, across the Coachella Valley and through the 

Banning Pass into the SCAB. The odors also crossed through the mountain passes west of 

the Salton Sea and into the Temecula Valley. The following day, SCAQMD received over 

235 complaints of sulfur and rotten egg type odors

As the Salton Sea recedes, the potential exists for more of these large-scale odor events to 

occur. SCAQMD has installed PM10 and H2S air monitors at Saul Martinez Elementary 

School and the Imperial Irrigation District’s Torrez-Martinez site to monitor the type of 

expected nuisance pollutants which are released from the Salton Sea. The primary objective 

of this monitoring network is to place monitoring resources at a lakeside location where peak 

hydrogen sulfide concentrations are expected to occur. The monitoring sites will provide 

data that can be used to assess population exposures in case of odor events and for 

comparison to the state standard for hydrogen sulfide. During 2015 the Saul Martinez 

Elementary School site will transition to become part of the permanent ambient air 

monitoring network.

As the Salton Sea is projected to recede, these sites will be further enhanced for monitoring 

the predicted particulate matter (PM) emissions from the Salton Sea area that may influence 

the South Coast Air Basin PM levels.

AllenCo

AllenCo is an oil field and gas production facility located in the City of Los Angeles 

surrounded by residences including low income housing units, F.D. Lanterman high school, 

and Mount Saint Mary’s College. For several years SCAQMD inspectors have responded to 

numerous odor complaints from the local community and suspects AllenCo to be the source 

of these odors. In October 2013 the SCAQMD initiated monitoring at sites around the 

AllenCo facility. At Mt. St Mary’s College regularly scheduled VOC samples are collected, 

and continuous Non-Methane Hydrocarbon measurements are also being collected. On the 

roof of the low income housing building across the street from AllenCo, there is a remote

controlled sampler capable of collecting a VOC grab sample should an odor complaint be 

called into the SCAQMD odor complaint line. In November 2013 AllenCo temporarily shut 

down operations to repair issues which it believes were the cause of the previous odor 

complaints. SCAQMD continues to monitor continuous Non-Methane Hydrocarbon 

Measurements as well as VOC samples.

Duarte

To better assess expansion of rock and quarry operations and its impact on residents of 

Duarte, SCAQMD began continuous PM10 monitoring on May 21, 2013. The study 

assesses levels of PM10 in the City of Duarte. SCAQMD is in the process of discussing with 

the city of Azusa for potential monitoring. 

CPV Sentinel

To better assess potential emission impacts from the CPV Sentinel power plant to the Desert 

Hot Springs area, SCAQMD has installed and is now operating an air pollution monitor 
Air Quality Monitoring Network Plan – July, 2015

22

directly downwind of the power plant at a Mission Springs Water District well site. 

Monitoring began on May 23, 2014 and measures levels of fine particulates (PM2.5) on a 

continuous basis, providing real-time hourly data (http://www.aqmd.gov/home/library/airquality-data-studies/special-monitoring/cpv-sentinel-monitoring).

Carlton Forge

Carlton Forge Works (CFW) operates furnaces, presses and grinders at its facility in 

Paramount to manufacture large metal rings used by aerospace and other industries. As part 

of its on-going investigation of air quality complaints and community concerns about 

potential burnt metal odors and emission from CFW, SCAQMD has deployed TSP monitors 

to monitor for metals. Based on the results of air sampling to date, SCAQMD has found 

ambient levels of some metals measured on few days in August, September and October 

2013 at concentrations significantly higher than average levels measured throughout the 

basin. However, more recent measured ambient concentrations have declined. 

Recent or Proposed Modifications to Network

Near Roadway NO2 Monitoring

On February 9, 2010, U.S. EPA promulgated new minimum monitoring requirements for the NO2 

monitoring network in support of newly revised 1-hour NO2 NAAQS and the retained annual 

NAAQS. In the new monitoring requirements, State and Local air monitoring agencies are required 

to install near-road NO2 monitoring stations at locations where peak hourly NO2 concentrations 

are expected to occur within the near-road environment in larger urban areas. On March 7, 2013 

EPA revised the new monitoring requirements from the 2010 NO2 NAAQS revision, delaying

implementation of the first phase of the near road network to January 1, 2014 and the second phase 

to January 1, 2015. As part of the implementation, State and local air agencies were required to 

consider traffic volumes, fleet mix, roadway design, traffic congestion patterns, local terrain or 

topography, and meteorology in determining where a required near-road NO2 monitor should be 

placed. In addition to those required considerations, there are other factors that impact the selection 

and implementation of a near-road monitoring station including satisfying siting criteria, site 

logistics (e.g., gaining access to property and safety), and population exposure. 

The primary objective of the near-road NO2 network is to place monitoring resources on nearroad locations where peak, ambient NO2 concentrations are expected to occur as a result of onroad mobile source emissions. Monitoring at such a location or locations within a particular urban 

area will provide data that can be used for comparison to the NAAQS and to assess population 

exposures for those who live, work, play, go to school, or commute within the near-roadway 

environment. Population density for SCAQMD is shown in Figure A. The near-road NO2 data 

will provide a clear means to determine whether or not the NAAQS is being met within the nearroad environment throughout a particular urban area. Since near-road NO2 monitoring sites are 

to be placed at locations with expected peak NO2 concentrations, the target mobile sources and 

the roads they travel upon are ubiquitous throughout urban areas, these monitoring data may be 

said to represent the relative worst case population exposures that may be occurring in the nearroad environment throughout an urban area over the averaging times of interest.
Air Quality Monitoring Network Plan – July, 2015

23

Minimum monitoring requirements are specified in 40 CFR 58 Appendix D. EPA requires state 

and local air agencies to operate one near-road NO2 monitor in each Core Based Statistical Area 

(CBSA) with a population of 500,000 or more persons. Further, those CBSAs with 2,500,000 or 

more persons, or those CBSAs with one or more roadway segments carrying traffic volumes of 

250,000 or more vehicles (as measured by annual average daily traffic [AADT] counts), shall have 

two near-road NO2 monitors. The process of identifying minimum monitoring requirements is 

shown in Figure B. 

The near roadway grant guidance directed implementation of near road sites be conducted in 

phases. The first of the Phase I sites became operational on January 1, 2014 in Anaheim adjacent 

to the 5 freeway (FE AADT #3, 2013). The Second Phase I site is located in Ontario adjacent to

Interstate 10/Interstate 15 (FE AADT #11, 2013) and began collecting data July, 2014. Phase II 

sites began collecting data on January 1, 2015. Sites are located along Route 710 in Long Beach 

(FE AADT 22, 2014) and along Route 60 in Ontario (FE AADT #9, 2014). 

Figure A – SCAQMD Population Density
Air Quality Monitoring Network Plan – July, 2015

24

The SCAQMD jurisdictional boundary encompasses two MSAs and two CBSAs whose 

boundaries and codes mirror those of the MSAs as defined by the U.S. Office of Management and 

Budget. The Los Angeles-Long Beach-Anaheim MSA\CBSA (Code 31080) has an estimated 

population of 13,131,431 and the Riverside-San Bernardino-Ontario MSA\CBSA (Code 40140) 

has an estimated population of 4,380,878 according to the most recent U.S. Census estimates 

available for 2013. The minimum number of monitors required for near road monitoring is based 

on MSA\CBSA population and shown in Table 8.

Figure B - Monitoring Requirements
Air Quality Monitoring Network Plan – July, 2015

25

TABLE 8. Minimum Number of Monitors Required Near Road NO2

The monitoring site selection process was in accordance with guidance published in the U.S. EPA 

Near Roadway NO2 Technical Assistance Document (TAD) (June, 2012). The process for 

ranking candidate road segments is outlined in Figure C. 

The candidate road segment ranking process incorporated the following EPA TAD considerations:

CBSA

Population 

Estimate 

(2013)

Highest 

AADT 

Segment 

(2013)

Minimum Required Near 

Road NO2 Sites 2014

Minimum Required Near 

Road NO2 Sites 2015

31080 13,131,431 377,000 1 1

40140 4,380,878 267,000 1 1

Figure C – Ranking Candidate Road Segments
Air Quality Monitoring Network Plan – July, 2015

26

FE AADT – A single metric to compare road segments, accounting for AADT and fleet mix (Heavy Duty 

Vehicles). The Fleet-Equivalent AADT value for each road segment is calculated by the following 

formula: 

(FE) AADT = (AADT – HDc) + (HDm * HDc)

Where AADT is the total traffic volume count for a particular road segment, HDc is the total 

number of heavy-duty vehicles for a particular road segment, and HDm is a multiplier that 

represents the heavy-duty to light-duty NOx emission ratio for a particular road segment. An HDm 

of 17 was used instead of the default national average of 10 based on emissions inventories within 

the SCAQMD jurisdiction (Air Quality Management Plan, South Coast Air Quality Management 

District, 2012). During 2013, and again in 2014, the top 50 FE AADT segment candidates were 

calculated based on the latest (2012) California Department of Transportation AADT counts at the 

time a decision was made on site location (http://traffic-counts.dot.ca.gov/). Traffic counts are

shown in Table 9. 
Air Quality Monitoring Network Plan – July, 2015

27

TABLE 9. Top Fifty FE AADT Candidate Roadway Segments

FE 

ADDT 

Rank

HD 

Rank

AADT 

Rank

FE 

AADT

AADT 

Total

(2012)

Total 

Trucks 

(HD)

Total 

Truck 

%

County Post 

mile Route

Description

1 15 4 754464 348000 25404 7.3 LA 23.56 60 DIAMOND BAR, JCT. RTE. 57

2 1 59 705536 260000 27846 10.71 LA 9.612 605 SANTA FE SPRINGS, JCT. 5

3 2 66 691976 255000 27311 10.71 LA 13.569 605 WHITTIER, JCT. RTE. 72

4 41 3 680560 362000 19910 5.5 ORA 34 5 SANTA ANA, JCT. RTES. 22 & 57

5 5 72 678400 250000 26775 10.71 LA 17.407 605 INDUSTRY, JCT. RTE. 60

6 14 45 674576 266000 25536 9.6 ORA 38.915 5 LINCOLN AVENUE

7 24 20 669968 292000 23623 8.09 LA 7.653 605 NORWALK, JCT. RTE. 105

8 16 50 669504 264000 25344 9.6 ORA 36.258 5 KATELLA AVENUE

9 3 117 656768 222000 27173 12.24 SBD 4.58 60 ONTARIO, JCT. RTE. 83

10 4 118 653800 221000 27050 12.24 SBD 2.366 60 CENTRAL AVENUE

11 17 78 646804 245300 25094 10.23 SBD 9.936 10 ONTARIO, JCT. RTE. 15

12 18 79 646804 245300 25094 10.23 SBD 11.132 10 ETIWANDA AVENUE

13 22 67 638048 254000 24003 9.45 LA 11.711 60 INDUSTRY, JCT. RTE. 605

14 8 120 636424 217000 26214 12.08 SBD 0 60 LOS ANGELES/SAN BERNARINO COUNTY LINE

15 23 64 635304 257000 23644 9.2 ORA 5.258 91 ANAHEIM, STATE COLLEGE BLVD

16 10 121 633488 216000 26093 12.08 LA 29.392 60 POMONA, JCT. RTE. 71,

17 28 31 627616 278000 21851 7.86 LA 44.014 5 LOS ANGELES, JCT. RTE. 210

18 11 125 625736 215000 25671 11.94 SBD 5.855 60 GROVE AVENUE

19 19 109 623760 226000 24860 11 SBD 24.24 10 COLTON, JCT. RTE. 215

20 20 105 621920 230000 24495 10.65 LA 20.428 60 ROWLAND HEIGHTS,

21 52 5 620400 330000 18150 5.5 ORA 30.263 5 TUSTIN, JCT. RTE. 55,

22 6 165 619008 192000 26688 13.9 LA 12.97 710 LONG BEACH, JCT. RTE. 91

23 34 27 613312 280000 20832 7.44 LA 36.358 5 LOS ANGELES, JCT. RTE. 170

24 25 85 608520 243800 22795 9.35 ORA 42.1 5 FULLERTON, JCT. RTE. 91

25 31 51 605296 264000 21331 8.08 ORA 2.615 91 BUENA PARK, JCT. RTE. 39 BEACH BLVD
Air Quality Monitoring Network Plan – July, 2015

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TABLE 9 (continued). Top Fifty FE AADT Candidate Roadway Segments

FE 

ADDT 

Rank

HD 

Rank

AADT 

Rank

FE 

AADT

AADT 

Total

(2012)

Total 

Trucks 

(HD)

Total 

Truck 

%

County Post 

mile Route

Description

26 13 161 603728 194000 25608 13.2 SBD 27.296 10 MOUNTAIN VIEW AVENUE

27 9 175 602640 184000 26165 14.22 LA 10.823 710 LONG BEACH, DEL AMO

28 36 40 599456 268000 20716 7.73 LA 13.094 91 LONG BEACH, CHERRY

29 35 43 598936 267000 20746 7.77 LA 39.361 5 LOS ANGELES, JCT. RTE. 118

30 61 8 591552 316000 17222 5.45 LA 17.17 101 LOS ANGELES, JCT. RTE. 405

31 38 52 590512 264000 20407 7.73 LA 11.681 91 LONG BEACH, JCT. RTE. 710

32 12 179 588112 178000 25632 14.4 LA 9.41 710 LONG BEACH, JCT. RTE. 405

33 40 55 586048 262000 20253 7.73 LA 14.618 91 BELLFLOWER, JCT. RTE. 19

34 47 38 583128 273000 19383 7.1 ORA 3.258 91 FULLERTON, HARBOR

35 27 112 577376 224000 22086 9.86 LA 25.464 60 DIAMOND BAR, JCT. RTE. 57 NORTH

36 44 60 573248 260000 19578 7.53 LA 9.87 110 LOS ANGELES, JCT. RTE. 91

37 65 22 560512 290000 16907 5.83 LA 5.046 605 CERRITOS, JCT. RTE. 91

38 51 54 560088 263000 18568 7.06 LA 36.41 210 DUARTE, JCT. RTE. 605,

39 74 16 559736 299000 16296 5.45 LA 19.99 101 ENCINO AVENUE

40 107 1 558700 377500 11325 3 ORA 20.751 405 JCT. RTE. 22 EAST,

41 29 139 555744 210000 21609 10.29 SBD 13.169 10 FONTANA, CHERRY AVENUE

42 96 7 552120 321000 14445 4.5 ORA 9.187 91 JCT. RTE. 55 SOUTH

43 63 32 551104 278000 17069 6.14 ORA 15.6 57 ANAHEIM, JCT. RTE. 91,

44 32 128 549552 214000 20972 9.8 LA 20.189 605 BALDWIN PARK, JCT. 10

45 108 2 547600 370000 11100 3 ORA 24.044 405 SEAL BEACH, JCT. RTE. 605

46 90 14 545400 303000 15150 5 ORA 11.54 91 PERALTA, JCT. RTE. 90

47 67 36 544728 275000 16858 6.13 LA 41.597 5 LOS ANGELES, JCT. RTE. 405

48 21 200 544360 155000 24335 15.7 RIV 0.491 60 JCT. RTE. 15

49 26 174 541076 185300 22236 12 SBD 29.313 10 ALABAMA STREET OC

50 43 111 539288 225000 19643 8.73 LA 15.692 710 LYNWOOD, JCT. RTE. 105
Air Quality Monitoring Network Plan – July, 2015

29

The process of ranking the roadway segments began with creating a scoring matrix incorporating 

EPA TAD considerations. The scoring matrix was used as a tool to determine the most suitable 

location for monitoring by incorporating traffic data and quantifying station siting considerations. 

FE AADT was weighted a factor of five due to the major role traffic influences near roadway 

monitoring. Other important factors such as roadway design, distance from roadway, 

meteorology, roadside structures and terrain were taken into consideration and weighted a factor 

of one each and are defined as follows:

Roadway Design – Considers monitor placement and can affect pollutant transport and dispersion. 

The most desirable attributes include a monitoring location at grade with the surrounding terrain 

and roadway. The least desirable attributes include deep cut-sections significantly below grade or 

significantly above grade.

Distance from Roadway - Per 40 CFR Part 58 Appendix E: the site should be “As near as 

practicable to the outside nearest edge of the traffic lanes of the target road segment; but shall not 

be located at a distance greater than 50 meters, in the horizontal, from the outside nearest edge of 

the traffic lanes of the target road segment.” The TAD recommends the target distance for nearroad NO2 monitor probes be within 20 meters of the target road whenever possible. 

Meteorology– Can affect pollution transport and dispersion. The most desirable location is 

relative downwind locations – winds from road to monitor. The least desirable locations are sites 

upwind of the target road. 

Roadside Structures – Considers monitor placement and can affect pollutant transport and 

dispersion. The most desirable monitoring location will have no barriers present other than low (< 

2m in height) safety barriers or guard rails. The least desirable attributes include the presence of 

sound walls, mature vegetation (high and thick) or obstructive buildings.

Terrain – Can affect pollutant dispersion and local atmospheric stability. The most desirable 

terrain is flat or gentle terrain, within a valley, or along road grade. The least desirable terrain is 

along mountain ridges or peaks, hillsides, or other naturally windswept areas. 

A scale normalized to 5 was used to rank each candidate segment; the scoring matrix is shown as 

Table 10.
Air Quality Monitoring Network Plan – July, 2015

30

TABLE 10. Candidate Segment Scoring Matrix

Score 5 3 1 0

FE AADT 

(Weighted 5x)

Traffic count of the 

highest ranked FE 

AADT

Normalized to the 

highest ranked FE 

AADT

Normalized to the 

highest ranked FE 

AADT

N/A

Roadway Design At same elevation Slightly higher 

elevation

Below grade / 

Under overpass / 

On bridge

Design prevents access 

or accurate 

representation of 

roadway.

Distance from 

Roadway

Less than or equal to 

20 m

Normalized distance 

from 20 m to 50 m

50 m from 

roadway >50 m

Meteorology 

(predominant wind 

direction)

Downwind Parallel Upwind N/A

Roadside Structures No barriers ( < 2 m)

Some obstruction 

(small sound barriers 

sparse low 

vegetation)

Major obstruction 

(large sound walls, 

buildings).

Completely blocked

Terrain Flat / mildly sloping Uneven Mountain ridges, 

Canyons

Terrain prevents access 

or accurate 

representation of 

roadway

Weighting Values

FE AADT 5

Roadway Design 1

Distance from Roadway 1

Meteorology 1

Roadside Structures 1

Terrain 1

The top FE AADT sites were surveyed and ranked according to the scoring matrix. Some sites had 

several locations within the road segment to consider and each location was scored individually as 

a sub-site. The results are shown for the Los Angeles-Long Beach-Anaheim MSA\CBSA (Code 

31080) and the Riverside-San Bernardino-Ontario MSA\CBSA (Code 40140) in Tables 11 and 12.
Air Quality Monitoring Network Plan – July, 2015

31

TABLE 11. Los Angeles-Long Beach-Santa Ana MSA\CBSA

Location

State College 

Blvd./Route 

91 Anaheim

Route 

710/91 

Long Beach

FE AADT Rank 15 22

FE AADT 635,304 619,008

HD Rank 23 6

HD 23,644 26,668

AADT Rank 64 165

AADT 257,000 192,000

Site 1A 1B 1C 2A 2B 3A 3B 4A 4B 5A 5B 5C 5D 6A 6B 7A 7B 8A 8B 8C 13A 13B 13C 13D 15A 22A

FE AADT Score 5.00 5.00 5.00 4.68 4.68 4.59 4.59 4.51 4.51 4.50 4.50 4.50 4.50 4.47 4.47 4.44 4.44 4.44 4.44 4.44 4.23 4.23 4.23 4.23 4.21 4.10

Roadway Design 4.5 4.0 5.0 4.5 4.5 3.0 5.0 4.0 5.0 5.0 2.0 2.0 4.0 4.0 5.0 1.0 2.0 3.0 3.0 1.0 5.0 2.0 2.0 4.0 1.0 5.0

Distance from 

Roadway 5.0 5.0 5.0 5.0 2.5 4.0 4.0 1.2 3.6 4.0 3.6 2.6 3.3 3.7 5.0 2.2 0.0 0.0 3.2 2.5 4.0 3.6 2.6 3.3 3.2 5.0

Meteorology 5.0 5.0 1.0 1.0 1.0 3.0 3.5 1.0 3.5 1.0 2.5 5.0 3.0 5.0 5.0 3.0 4.0 4.0 4.0 4.0 1.0 2.5 5.0 3.0 4.0 5.0

Roadside Structures 4.0 4.0 1.0 3.0 5.0 3.0 4.0 4.0 4.0 4.0 1.0 1.0 1.0 5.0 5.0 1.0 1.0 2.5 2.5 2.5 4.0 1.0 1.0 1.0 1.0 5.0

Terrain 3.5 4.0 4.0 4.0 3.0 2.0 5.0 4.0 5.0 5.0 2.0 2.0 3.5 3.0 5.0 4.0 4.0 3.0 3.0 3.0 5.0 2.0 2.0 3.5 3.0 5.0

Sum (Out of 50) 4.70 4.70 4.10 4.09 3.94 3.79 4.44 3.68 4.36 4.15 3.36 3.51 3.73 4.31 4.74 3.34 3.32 3.47 3.79 3.52 4.01 3.22 3.38 3.60 3.32 4.55

Overall Ranking 2 2 8 9 11 12 4 14 5 7 20 17 13 6 1 21 22 18 12 16 10 23 19 15 22 3

Route 5/Katella 

Anaheim

Route 60/605 City 

of Industry

8 13

260,000 255,000 362,000

59 66 3

1 2 41

27,846 27,311 19,910

4

Route 605/60 City of 

Industry

Route 

5/Lincoln 

Anaheim

Route 

605/105 

Norwalk

5 6 7

348,000

Route 

5/605 

Santa Fe 

Springs

Route 

605/72 

Whittier

Route 

5/22/57 

Orange

705,536 691,976 680,560

Route 57/60 

Diamond Bar

1

754,464

15

25,404

4

2 3

674,576 669,968 669,504 638,048

5 14 24 16 22

678,400

26,775 25,536 23,623 25,344 24,003

72 45 20 50 67

250,000 266,000 292,000 264,000 254,000
Air Quality Monitoring Network Plan – July, 2015

32

TABLE 12. Riverside-San Bernardino-Ontario MSA\CBSA

Location

Route 60/83 

Ontario

Route 

10/Etiwanda 

Ontario

Route 60 LA/SB 

County Line 

Chino

Route 60/71 

Pomona

Grove Ave/Route 

60 Ontario

FE AADT Rank 9 12 14 16 18

FE AADT 656,768 646,804 636,424 633,488 625,736

HD Rank 3 18 8 10 11

HD 27,173 25,094 26,214 26,093 25,671

AADT Rank 117 79 120 121 125

AADT 222,000 245,300 217,000 216,000 215,000

Site 9A 10A 10B 10C 11A 11B 12A 14A 16A 18A

FE AADT Score 4.35 4.33 4.33 4.33 4.29 4.29 4.29 4.22 4.20 4.15

Roadway Design 3.0 2.0 2.0 2.0 4.0 3.0 5.0 1.0 1.0 3.0

Distance from Roadway 2.0 3.3 3.3 4.0 0.0 1.7 5.0 2.6 4.0 4.5

Meteorology 3.5 2.5 2.5 3.0 3.0 4.0 5.0 3.0 3.0 4.0

Roadside Structures 2.5 3.0 4.0 3.0 5.0 1.0 5.0 3.0 1.0 4.0

Terrain 3.5 2.0 4.0 4.0 4.0 2.0 5.0 3.0 3.0 4.0

Sum (Out of 50) 3.63 3.45 3.75 3.77 3.74 3.31 4.64 3.37 3.30 4.03

Ranking 6 7 4 3 5 9 1 8 10 2

221,000 245,300

4 17

27,050 25,094

118 78

Route 60/Central 

Chino

Route 10/15 

Ontario

10 11

653,800 646,804
Air Quality Monitoring Network Plan – July, 2015

33

Level of Service (congestion) data is considered to differentiate between two comparatively ranked 

segments as part of the site selection process. Tables 13, 14 and 15 show the latest congestion data 

available for the Los Angeles, Orange, and the Riverside-San Bernardino-Ontario MSA\CBSA 

used when site locations were decided. Data is shown in the following table as reported by the 

California Department of Transportation and can be found at

(http://www.dot.ca.gov/hq/traffops/sysmgtpl/MPR/index.htm).

TABLE 13. Top Congested Freeways Los Angeles County

TABLE 14. Top Congested Freeways Orange County
Air Quality Monitoring Network Plan – July, 2015

34

TABLE 15. Top Congested Freeways Riverside & San Bernardino Counties

Sites were selected based on their ranking in the scoring matrix. A review of the latest data 

available (2013) shows variation in AADT traffic counts however site selections remain consistent 

when ancillary considerations are taken into account. Other considerations involved in the site 

selection process as directed in the Near Road Technical Assistance Document include:

Safety - Near-road monitoring sites must be accessible to station operators in a safe and legal manner, 

and not pose safety hazards to drivers, pedestrians, or nearby residents. Safety hazards to monitoring 

site operators include factors which inhibit the safe entrance to or egress from a site and factors that 

could allow vehicles to encroach upon and damage the site infrastructure.

Accessibility – ability to access the desired location from the property owner or ability to obtain a 

right of way permit.

Infrastructure – availability of power and data connection at the site.

On December 14, 2012, U.S. EPA strengthened the NAAQS for PM2.5 and as part of the revisions,

a requirement was added to monitor near heavily trafficked roads in large urban areas. Particle 

pollution may be higher along these roads as a result of emissions from cars and heavy-duty diesel 

trucks and buses. The U.S. EPA requirement is for one near-roadway PM2.5 monitor to measure

in each CBSA with a population of 1 million or more. The monitors were to be phased in for the 

largest CBSAs (population of 2.5 million or more) by January 1, 2015. SCAQMD has timely 

installed two monitors, whose locations were selected based upon the existing near roadway NO2 

site per CBSA that was ranked higher for heavy duty diesel traffic. Thus, the 710 freeway site in 

Long Beach was selected for the Los Angeles-Long Beach-Anaheim CBSA, and the Route 60 site 

in Ontario was selected for the Riverside-San Bernardino-Ontario CBSA. 

During June, 2014 an Annual Network Plan Workshop was conducted at SCAQMD’s Diamond 

Bar office to solicit input from stakeholders. SCAQMD staff presented and held a discussion on 
Air Quality Monitoring Network Plan – July, 2015

35

SCAQMD’s selection of near road sites. Written comments were received in 2013 by the National 

Defense Resources Council (NRDC) regarding support for placing a site along the 710 freeway 

for a Los Angeles-Long Beach-Anaheim CBSA near road monitoring location.

Crestline

SCAQMD has been operating the Crestline site since 1973. The deteriorating state of the shelter 

along with compromises made to the siting criteria due to obstructions has made it a candidate for 

site improvement. As part of regular air monitoring station maintenance, a new station shelter has 

been outfitted to replace the existing trailer. SCAQMD is working with San Bernardino County 

Planning, Building and Safety departments to receive approval for construction plans. 

Construction is anticipated during fall 2015; however the schedule is dependent upon the approval 

and contract process.

West LA

SCAQMD has been operating the West LA site since 1983. The deteriorating state of the shelter 

along with compromises made to the siting criteria due to obstructions has made it a candidate for 

site improvement. As part of regular air monitoring station maintenance, a new station shelter has 

been outfitted to replace the existing platform. However, due to recent legislation, the SCAQMD 

lease is under review by the Veterans Administration. Construction schedule is dependent upon 

pending lease review.

Riverside Magnolia

SCAQMD has been operating the Riverside Magnolia site since October, 1972. The deteriorating 

state of the building along with compromises made to the siting criteria due to obstructions, and 

safety issues, made it necessary to close the site during March, 2015. SCAQMD in consultation 

with EPA Region IX is assessing the relocation of the site in the 5 year network assessment. 

Burbank

SCAQMD has been operating the Burbank site since October, 1961. Due to the termination of the 

lease by owner, the site was shut down June, 2014. SCAQMD is working with Los Angeles 

County to find a suitable location for monitoring within 2.5 miles of the previous location. 

SCAQMD is in consultation with EPA Region IX and is assessing the relocation of the site in the 

5 year network assessment. 

Ontario Fire Station

SCAQMD has been operating the Ontario site since January, 1999. Due to the termination of lease 

by the owner, the site was shut down June, 2014. SCAQMD is working to find a suitable location 

for monitoring or consolidation with nearby sites. SCAQMD is in consultation with EPA Region 

IX and is assessing the relocation of the site in the 5 year network assessment. 

South Long Beach

SCAQMD has been operating the South Long Beach station as part of the ambient air-monitoring 

network. Recent construction of the buildings adjacent to the site potentially compromises the 

siting criteria. During the FY 2015-16 a data comparison between a more centralized monitoring 

location in Long Beach will be undertaken. If comparison of data between the two locations 
Air Quality Monitoring Network Plan – July, 2015

36

demonstrates some comparability, or if the metropolitan site shows consistently higher levels of 

PM, the South Long Beach site may be relocated in consultation with EPA Region IX.

Long Beach (North)

At the request of the owner, the Long Beach (North) site lease was terminated on September 30, 

2013. As a result some pollutants were discontinued while a replacement site is sought. 

Consideration is being given to consolidation with nearby sites to better represent the Long Beach 

area and will be addressed in the 5 year network assessment.

Minimum Monitoring Requirements

The SCAQMD jurisdictional boundary encompasses two MSAs and two CBSAs whose 

boundaries and codes mirror those of the MSAs as defined by the U.S. Office of Management and 

Budget. Los Angeles-Long Beach-Anaheim MSA\CBSA (Code 31080) has an estimated

population of 13,131,431 and the Riverside-San Bernardino-Ontario MSA\CBSA (Code 40140) 

has an estimated population of 4,380,878 according to U.S. Census estimates for 2013. The 

minimum number of monitors for each pollutant is based on MSA population as described in 40 

CFR § 58 Appendix D. The SCAQMD is a Primary Quality Assurance Organization (PQAO) and 

the network exceeds the minimum monitoring requirements for all criteria pollutants. Details are 

provided below.

 
Air Quality Monitoring Network Plan – July, 2015

37

Table 16 Minimum Monitoring Requirements for Ozone.

(Note: Refer to section 4.1 and Table D-2 of Appendix D of 40 CFR Part 58.)

MSA Counties Population and 

Census Year

8-hr Design 

Value (ppb) DV, 

Years1

Design Value Site 

(name AQS ID0

Monitors 

Required

Monitors 

Active

Monitors 

Needed

30180 Los Angeles 

Orange

13,131,431 

2013

97

2012-2014

Santa Clarita

060376012 4 16 0

40140 San Bernardino

Riverside

4,380,878

2013

102

2012-2014

Redlands

060714003 3 13 0

1DV Years – The three years over which the design value was calculated.

Monitors required for SIP or Maintenance Plan: 29

Table 17a Minimum Monitoring Requirements for PM2.5 SLAMS (FRM/FEM/ARM)

(Note: Refer to sections 4.71, 4.72, and Table D-5 of Appendix D of 40 CFR Part 58.)

MSA Counties

Population 

and Census 

Year

Annual 

Design 

Value 

[ug/m3], 

DV & 

Years1

Annual 

Design 

Value Site 

(Name, 

AQS ID)

Daily 

Design 

Value 

[ug/m3], 

DV &

years

Daily 

Design 

Value site 

(name 

AQS ID)

# 

Required 

SLAMS

Monitors

# Active 

SLAMS 

Monitors

# 

Additional 

SLAMS 

needed

30180 Los Angeles 

Orange

13,131,431

2013

12.4

2012-2014

Los 

Angeles

060371103

32

2012-

2014

Los 

Angeles

060371103

3 10 0

40140 San Bernardino

Riverside

4,380,878

2013

14.7

2012-2014

Mira Loma

060658005

38

2012-

2014

Mira Loma

060658005 3 9 0

1DV Years – The three years over which the design value was calculated.

Monitors required for SIP or Maintenance Plan: 19
Air Quality Monitoring Network Plan – July, 2015

38

Table 17b Minimum Monitoring Requirements for Continuous PM2.5 Monitors (FEM and 

Non-FEM)

*

(FEM/ARM and non-FEM see 40 CFR 58 Appendix D Section 4.72.)

MSA Counties

Population 

and Census 

Year

Annual 

Design 

Value 

[ug/m3], 

DV &

Years1

Annual 

Design 

Value Site 

(Name, 

AQS ID)

Daily 

Design 

Value 

[ug/m3], 

DV & 

years

Daily Design 

Value site 

(name AQS 

ID)

# Required 

Continuous 

Monitors

# Active 

Continuous 

Monitors

# 

Additional 

Continuous

needed

30180 Los Angeles 

Orange

13,131,431

2013

19.58

2012-2014

Los Angeles

060371103

41.7,

2012-2014

Los Angeles

060371103 2

4-FEM

3-Non FEM 0

40140

San 

Bernardino

Riverside

4,380,878

2013

19.37,

2012-2014

Mira Loma

060658005

52.6,

2012-2014

Rubidoux

060658001 2

3-FEM

6-Non FEM2 0

1DV Years – The three years over which the design value was calculated.

Monitors required for SIP or Maintenance Plan: 15

2One Non FEM is collocated at the Rubidoux site with a FEM.

* Currently all active continuous monitors do not meet acceptance criteria under 78 FR 3086 and is requested to not be compared 

to the NAAQS.

Table 17c Minimum Monitoring Requirements for Speciated PM2.5 Monitors 

(Note: Refer to sections 4.74 of Appendix D of 40 CFR Part 58.)

MSA Counties

Population 

and Census 

Year

Monitors 

Required1

Monitors 

Active

Monitors 

Needed

30180 Los Angeles 

Orange

13,131,431

2013 1 2 0

40140

San 

Bernardino

Riverside

4,380,878

2013 1 2 0

1Sites designated as part of the PM2.5 Speciation Trends Network (STN).

Monitors required for SIP or Maintenance Plan: 4
Air Quality Monitoring Network Plan – July, 2015

39

Table18 Minimum Monitoring Requirements for PM10

(Note: Refer to section 4.6 and Table D-4 of Appendix D of 40 CFR Part 58.)

MSA Counties Population and 

Census Year

2014 Max 

Concentration 

[ug/m3]

Max 

Concentration 

site (name AQS 

ID)

# Required 

Monitors

# Active 

Monitors

# Additional 

Monitors 

Needed

30180 Los Angeles 

Orange

13,131,431

2013 98 Azusa060370002

2-4

Low Conc 8 0

40140

San 

Bernardino

Riverside

4,380,878

2013 1361 San Bernardino060719004

4-8

Med Conc 11 0

Monitors required for SIP or Maintenance Plan: 19

1Excluding high concentration at Indio (298 ug/m3, on 8/18/2014.)

Table 19 Minimum Monitoring Requirements for NO2

(Note: Refer to section 4.3 of Appendix D of 40 CFR Part 58.)

CBSA Population and 

Census Year

Max 

AADT 

Counts 

(2013)

1

# 

Required 

Near Road 

Monitors2

#Active 

Near Road 

Monitors

#Additional 

Near Road 

Monitors 

Needed

#Required 

Area Wide 

Monitors

#Active 

Area 

Wide 

Monitors

#Additional 

Area wide 

Monitors 

Needed

30180 13,131,431

2013

377,000

2013

2 2 0 1 15 0

40140 4,380,878

2013

267,000

2013

2 2 0 1 8 0

1Max AADT Counts – 2013 is the latest data available from CA DOT

2Four required beginning January 1, 2015.

Monitors required for SIP or Maintenance Plan: 13 (area wide), 4 (near road)

Monitors Required for PAMS: 7

EPA Regional Administrator-required monitors per 40 CFR 58, Appendix D 4.3.4: 3
Air Quality Monitoring Network Plan – July, 2015

40

Table 20 Minimum Monitoring Requirements for SO2

(Note: Refer to section 4.4 of Appendix D of 40 CFR Part 58.)

CBSA Counties Total SO21

[tons/year]

Population Weighted Emissions 

Index2

[million persons-tons per year]

#Active 

Near Road 

Monitors

#Required 

Area 

Wide 

Monitors

#Active 

Area 

Wide 

Monitors

#Additional 

Area wide 

Monitors 

Needed

30180 Los Angeles 

Orange

6102.45

 2013 80,134 0 1 4 0

40140

San 

Bernardino

Riverside

2307.02

2013 10,107 0 1 2 0

1Using latest NEI data 2013, available on EPA website: http://www.epa.gov/ttn/chief/net/2013inventory.html

2Calculated by multiplying CBSA population and total SO2 and dividing product by one million.

Monitors required for SIP or Maintenance Plan: 6

EPA Regional Administrator-required monitors per 40 CFR 58, Appendix D 4.4.3: 0

Table 21 Minimum Monitoring Requirements for CO

(Note: Refer to section 4.2 of Appendix D of 40 CFR Part 58.)

CBSA

Population 

and Census 

Year

#Required 

Near Road 

Monitors1

#Active 

Near 

Road 

Monitors2

#Required 

Area 

Wide 

Monitors

#Active 

Area 

Wide 

Monitors

30180 13,131,431

2013 1 1 0 16

40140 4,380,878

2013 1 1 0 7

1Required beginning January 1, 2015

2Required sites to be active by January 1, 2015; to be collocated with near road NO2 sites.

Monitors required for SIP or Maintenance Plan: 23 (area wide), 2 (near road)

EPA Regional Administrator-required monitors per 40 CFR 58, Appendix D 4.4.2: 0

Table 22a Minimum Monitoring Requirements for Pb at NCore

(Note: Refer to section 4.5 of Appendix D of 40 CFR Part 58.)

NCore Site

(name, AQS ID)

CBSA Population and 

Census Year

# Required 

Monitors # Active Monitors # Additional Monitors Needed

Los Angeles (Main 

Street)

060371103

30180 13,131,431

2013 1 1 0

Rubidoux

060658001 40140 4,380,8782013 1 1 0
Air Quality Monitoring Network Plan – July, 2015

41

Table 22b Source Oriented Pb Monitoring (Including Airports)

(Note: Refer to section 4.5 of Appendix D of 40 CFR Part 58.)

1Consider data from past three years.

2Data found at http://www.epa.gov/ttn/chief/net/2011inventory.html (5/1/2015)

Monitors Required for SIP or Maintenance Plan: 5

EPA Regional Administrator required monitors per 40 CFR 58, Appendix D 4.5(C) c: 0

Table 22c Minimum Monitoring Requirements for Pb, Non Source, Non NCore Monitoring 

(Note: Refer to section 4.5 of Appendix D of 40 CFR Part 58.)

1DV Years – The three years over which the design value was calculated.

CBSA Population and 

Census Year

Annual Design 

Value [ug/m3], 

DV & Years1

# Required Area 

Wide Monitors

# Active Area 

Wide Monitors

# Additional 

Monitors Needed

30180 13,131,431

2013

0.01,

2012-2014 0 4 0

40140 4,380,878

2013

0.01,

2012-2014 0 2 0

Source Name Address

Pb Emissions1 

(tons per year)

Emission Inventory 

Source2 and Data Year

Max 3-Month Design 

Value1 [ug/m3]

Design Value 

Date(third month, 

year)

# Required 

Monitors

# Active 

Monitors

# Additional 

Monitors Needed

Long Beach Airport 

Daugherty Field

4100 E Donald Douglas 

Dr, Long Beach, CA 

90808

0.8 NEI 2011 Unavailable Unavailable

Pending 5 

year 

assessment

0 0

Van Nuys Airport 16461 Sherman Way, Van 

Nuys, CA 91406 0.68 NEI 2011 0.06 7; 2012 0 0 0

TAMCO

12459-B Arrow Route, 

Rancho Cucamonga, CA 

91739

0.42 NEI 2011 Unavailable Unavailable 0 1 0

Exide Technologies 2700 S Indiana St, Vernon, 

CA 90058 0.1 NEI 2011 0.46 7; 2011 1 2 0

Trojan Battery 9440 Ann St., Santa Fe 

Springs, CA 90670 0.00556 NEI 2011 0.11 4; 2011 0 1 0

Quemetco Inc. 720 S 7th Ave, City Of 

Industry, CA 91746 0.0048 NEI 2011 0.11 7; 2010 0 1 0
Air Quality Monitoring Network Plan – July, 2015

42

Table 23 Minimum Monitoring Requirements for PAMS

(Note: Refer to section 4.5 of Appendix D of 40 CFR Part 58.)

Table 24 Collocated Manual PM2.5, PM10, and Non-NCore Pb Networks

(Note: Refer to section 3.2.5, 3.3.5, 3.3.1, and 3.3.4.3 of Appendix A, 40 CFR Part 58.)

Table 25 Collocated Automated (continuous) PM2.5 Network 

(Note: Refer to section 3.2.5 & 3.3.5 of Appendix A, 40 CFR Part 58.)

1No FEM PM2.5 BAMs are listed as primary monitors; therefore no collocation requirement exists but all are collocated with 

FRM monitors.

Area Type # Required PAMS 

Sites

# Active PAMS 

Sites

# PAMS Sites 

Needed

SCAQMD 

Monitoring Area

1 or 3 1 3 0

2 1 4 0

4 0 0 0

Upper Air 

Meteorology 1 5 0

Pollutant Method Code # Primary 

Monitors

# Required 

Collocated Monitors

# Active Collocated 

Monitors

PM2.5 (RAAS) 780, 120 19 3 3

PM10 (SSI Hi-Vol) 063, 102 19 3 3

Pb (TSP Hi-Vol) 110 (Non Source) 8 1 2

Pb (Tsp Hi-Vol) 110 (Source) 5 1 1

Method Code

# Primary 

Monitors

# Required 

Collocated Monitors

# Active Collocated 

Monitors1

None 0 0 6
Air Quality Monitoring Network Plan – May 2015

Data Submittal and Archiving Requirements

As required in 40 CFR 58.16(a), data is reported via AQS including all ambient air quality data 

and associated quality assurance data for SO2, CO, O3, NO2, Near Road NO2, NO, NOy, NOX, 

Pb-TSP mass concentration, Pb-PM10 mass concentration, PM10 mass concentration, PM2.5

mass concentration, filter-based PM2.5 FRM/FEM field blank mass, sampler-generated average 

daily temperature, and sampler-generated average daily pressure, chemically speciated PM2.5 

mass concentration data, PM10-2.5 mass concentration, meteorological data from NCore and 

PAMS sites, average daily temperature\average daily pressure for Pb sites and metadata 

records\information as specified by the AQS Data Coding Manual through December 31, 2014. 

A data certification letter has been submitted to the EPA Regional Administrator certifying

applicable data collected at all SLAMS and at all FRM, FEM, and ARM SPM stations that meet 

criteria in appendix A, to part 58, for January 1 through December 31, 2014.