Annual Monitoring 

Network Report

for

Twenty-three Districts in California

June 2014

California Environmental Protection Agency

Air Resources Board

ANNUAL MONITORING NETWORK REPORT

FOR

TWENTY-THREE DISTRICTS IN CALIFORNIA

California Air Resources Board

June 2014

Table of Contents

Section 1 Introduction............................................................................. 1

Section 2 Monitoring network overview.................................................... 6

Section 3 Site and monitoring information........................................... 7

Section 4 Additional information about the monitors............................. 18

Section 5 Federal minimum monitoring requirements............................. 27

Section 6 Federal monitoring requirements at State-level or by PQAO or

 Area............................................................................................. 36

6.1 Collocation requirements................................................... 37

Section 7 Federal air quality assurance........................................... 44

Section 8 Operating schedules.......................................................... 51

Section 9 Additional information on PM2.5 monitors............................. 55

9.1 Suitability for comparison to the annual PM2.5 NAAQS........... 55

9.2 Review of changes to PM2.5 network.................................. 55

Section 10 Proposed and recently implemented monitoring site changes.. 57

Section 11 Access to more information about the network................... 59

Appendix A Regulatory language of 40 CFR 58.10.............................. 63

Appendix B Minimum monitoring requirements for O3, PM2.5 and PM10.... 67

Appendix C Supporting documents included in the network plan............... 71

Appendix D Acronymns............................................................................... 80

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i Annual Monitoring Network Report for Twenty-three Districts in California
List of Tables

Table 1 Districts Included in the ARB PQAO......................................... 3

Table 2 Location of Information Required for Annual Network Plan......... 5

Table 3 Site and Monitoring Information............................................... 11

Table 4 Additional Information About the Monitors.................................. 19

Table 5 Monitoring Sites Operating PM2.5 non-FEMs................................ 26

Table 6 Numbers of Required and Existing Sites by Core-based

 Statistical Area (CBSA)......................................................... 28

Table 6a Core-Based Statistical Areas in California.................................... 30

Table 7 Near-road NO2 Monitoring Requirements in California.................. 32

Table 8 Minimum Monitoring Requirements for SO2............................ 34

Table 9 NCore Monitoring in California....................................................... 36

Table 10 Collocation Requirements for Manual PM2.5 Monitors................. 38

Table 11 Collocation Requirements for Continuous PM2.5 FEM............... 39

Table 12 Design Values for PM2.5 Collocation Sites.................................... 40

Table 13 Distance between Collocated PM Monitors.................................. 42

Table 14 2013 Audit Date Information for the Monitors in this Plan............ 47

Table 15 2013 Gaseous Inlet Probe Residence Time................................. 49

Table 16 Current PM2.5 FRM Operating Schedules and Design Values.... 52

Table 17 Max Concentrations of the PM10 FRM Sites............................... 53

List of Figures

Figure 1 The ARB PQAO..................................................................... 4

Figure 2 Map showing the CBSAs in California......................................... 29

Figure 3 Through-the-Probe Audit............................................................. 45

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ii Annual Monitoring Network Report for Twenty-three Districts in California
Section 1. Introduction

Federal regulations require State and local agencies that conduct ambient air 

monitoring for regulatory purposes to submit an Annual Monitoring Network 

Report, beginning in 2007. The report must contain specific monitoring network 

information and be available for a 30-day public inspection period prior to 

submittal to the U.S. Environmental Protection Agency (U.S. EPA). This report 

meets the requirements specified in Title 40, Code of Federal Regulations, 

Part 58.10 (40 CFR 58.10) for a subset of the California monitoring network.

This report covers the monitoring network for 23 of the 32 air districts within the 

Air Resources Board (ARB) Primary Quality Assurance Organization (PQAO). A 

PQAO is the umbrella under which monitoring agencies are organized to ensure 

that monitoring is conducted according to a common set of procedures, using 

common calibration facilities and standards, and that oversight is conducted by 

one air quality organization. Most of the districts in California are included in the 

ARB PQAO. The exceptions are the South Coast, San Diego, and Bay Area 

districts, which each comprise their own PQAO. Each PQAO is responsible for 

their monitoring network and reports directly to U.S. EPA on monitoring network 

requirements.

Table 1 lists the districts in the ARB PQAO that are included within the scope of 

this report, as well as those districts that are preparing their own report. This 

report covers documentation of the monitoring network for the period of 

January 1 through December 31, 2013, along with a discussion of proposed 

changes to the network. Consistent with directions from the U.S. EPA, this report 

includes monitors operated by the local districts, ARB, and other agencies within 

the jurisdiction of the region included in this report. This includes monitors 

designated as State and Local Air Monitoring Sites (SLAMS), National Core 

(NCore) multi-pollutant monitoring stations, Special Purpose Monitoring (SPM), 

and other types of monitors operated by ARB, air districts, and National Park 

Service (NPS). This report also includes the Federal Reference Method (FRM) 

and Federal Equivalent Method (FEM) monitors. 

This report documents that the area covered by this report complies with federal 

monitoring requirements, which are specified in 40 CFR 58, Appendices A 

through E. Table 2 identifies the elements from 40 CFR 58.10 that are required 

to be included in the annual report. The requirements are comprehensive and 

include information on items such as minimum monitoring requirements, monitor 

operation, monitor siting, sampling schedule, and quality assurance activities.

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1 Annual Monitoring Network Report for Twenty-three Districts in California
Overview of Report

Table 1 and Figure 1 identify the 23 air districts within the ARB PQAO covered in 

this report as well as the 9 districts in the ARB PQAO that are preparing their own 

report. A brief summary of elements included in this report is listed below.

• Summary of CFR elements required for inclusion in the report;

• Detailed information on each monitor;

• Minimum monitoring requirements and compliance with these 

requirements;

• PM collocation requirements;

• PM design values;

• PM2.5 FRM operating schedules;

• Proposed and implemented network changes.

In compiling this report, ARB solicited input from and review by the local air 

districts whose jurisdictions are included. Also, the report was available for a 

30 day public inspection period prior to its submittal to the U.S. EPA. This report

can be downloaded from the internet at www.arb.ca.gov/aqd/amnr/amnr.htm.

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2 Annual Monitoring Network Report for Twenty-three Districts in California
Table 1

Districts Included in the ARB Primary Quality Assurance Organization (PQAO)

Air districts that are Air districts drafting

included in this ARB report their own Annual Network Plans

 Amador County APCD Great Basin Unified APCD

 Antelope Valley APCD Imperial County APCD

 Butte County AQMD Monterey Bay Unified APCD

 Calaveras County APCD North Coast Unified AQMD

 Colusa County APCD Sacramento Metropolitan AQMD

 Eastern Kern APCD San Joaquin Valley APCD

 El Dorado County AQMD San Luis Obispo County APCD

 Feather River AQMD Santa Barbara County APCD

 Glenn County APCD Ventura County APCD

 Lake County AQMD

 Lassen County APCD

 Mariposa County APCD

 Mendocino County AQMD

 Modoc County APCD

 Mojave Desert AQMD

 Northern Sierra AQMD

 Northern Sonoma County APCD

 Placer County APCD

 Shasta County AQMD

 Siskiyou County APCD

 Tehama County APCD

 Tuolumne County APCD

 Yolo-Solano AQMD

Notes:

APCD stands for Air Pollution Control District.

AQMD stands for Air Quality Management District.

The South Coast, San Diego and Bay Area districts are not included in this table. These three 

districts are drafting their own network plan because they are designated PQAOs.

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3 Annual Monitoring Network Report for Twenty-three Districts in California
Figure 1

California PQAOs

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4 Annual Monitoring Network Report for Twenty-three Districts in California
Table 2

Location of Information Required for Annual Network Plan

Elements required by 40 CFR 58.10 Location in Annual Network Plan

Monitoring purpose information Section 3

Evidence that siting and operation 

criteria are met:

 40 CFR 58, Appendix A Section 6 & 7

 40 CFR 58, Appendix B Section 7

 40 CFR 58, Appendix D Section 5 & 6

 40 CFR 58, Appendix E Section 7

Air Quality System Site Identification 

Number (AQS Site ID) Section 3, Table 3

Section 4, Table 4

Location of sites

 Street address Section 3, Table 3

 Geographic coordinates Section 4, Table 4

Sampling and analysis methods of 

monitors Section 4, Table 4

Operating schedules for monitors Section 8

Proposals to move/remove stations Section 10

Monitoring objectives and spatial scale Sections 3 & 4, Tables 3 & 4

Sites suitable or not for comparison to 

the annual PM2.5 National Ambient Air Section 9.1

Quality Standard

Core-Based statistical area information Section 3, Tables 3

(Metropolitan and Micropolitan) Section 4, Table 4

Section 5, Tables 6, 6a, 7 & 8

Appendix B

Review of changes to PM2.5 Network Section 9.2

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5 Annual Monitoring Network Report for Twenty-three Districts in California
Section 2. Monitoring Network Overview

California’s ambient air monitoring network is one of the most extensive in the 

world, consisting of over 250 sites where air pollution levels are monitored and 

more than 700 monitors used to measure the pollutant levels. A monitoring 

network this large is needed to cover the diverse range of topography, 

meteorology, emissions, and air quality in California, while adequately 

representing a large population. The monitoring network is critical in assessing 

the State’s clean air progress and in determining pollutant exposures in 

California. 

The network of monitoring sites for a pollutant tends to be denser where the air 

quality problem is worse and where the population is greater. The monitoring 

network also strives to provide representative data to all the broad geographical 

areas in California, including coastal, interior valleys, desert, and mountainous 

regions. Monitoring is also conducted in Mexico, across the border from San 

Diego and Imperial counties. Monitors are operated by ARB, some by local air 

districts, and a few by other entities including the National Park Service, private 

contractors, and tribal authorities. Note that tribal monitors are not included in 

this report.

Ambient concentration data are collected for a wide variety of pollutants. These

include ozone (O3), particulate matter with a diameter of 2.5 microns or less 

(PM2.5), particulate matter with a diameter of 10 microns or less (PM10), and a 

number of toxic compounds. While toxics monitoring plays an integral part in air 

monitoring programs, this report only covers those pollutants specified by federal 

requirements to be included in the annual monitoring network plans. Monitoring 

for meteorological parameters is also conducted at a number of sites. The data

is needed to better understand and inform the public about the nature of the 

ambient air quality problems in California. 

Not all pollutants are monitored at all sites, although most sites monitor for 

multiple pollutants. The State and local air quality agencies in California make 

the effort to only collect data that is needed from each site. The needs for the 

monitoring data are varied. A sense for this can be gathered from the information 

on monitoring objectives and purposes in the next section of this report. A 

fundamental purpose of monitoring is to distinguish between areas where 

pollutant levels violate the ambient air quality standards and areas where they do 

not. Health-based ambient air quality standards are set at levels of pollutant 

concentrations that protect against adverse impacts to human health. Areas in 

violation of a standard usually have increased efforts to reduce the sources of 

pollution that result in the exceedances. In other words, air quality agencies 

develop strategies and regulations to achieve needed emission reductions. Data 

from the ambient monitoring network are then used to indicate the success of 

this, in terms of the rate of progress towards attaining the standards or to show 

that standards have been attained.

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6 Annual Monitoring Network Report for Twenty-three Districts in California
Section 3. Site and Monitoring Information

This section details monitoring information for the sites and monitors that fall 

within the geographical scope of this report. U.S. EPA requires three types of 

information to be included in the annual network plans. These are: federal site 

type, federal monitoring objective, and federal monitor type. The first three 

subsections, below, describe these federal monitoring requirements. The fourth 

subsection provides detail on state and local monitoring purposes, which 

encompass a broader scope of active program areas than the federal monitoring 

requirements. 

Federal Site type

Monitoring sites must be capable of informing air quality program managers 

about many things including the peak air pollution levels, typical levels in 

populated areas, air pollution transported into and outside of a city or region, air 

pollution levels near specific sources. For these reasons, U.S. EPA requires that 

each monitor at a site be designated, at a minimum, with one of the twelve site 

types that are established in the Air Quality System (AQS) database. The twelve 

site types are:

Extreme Downwind Max Ozone Concentration

Highest Concentration Max Precursor Emissions Impacts

Population Exposure Source Oriented

Upwind Background Welfare Related Impacts

Regional Transport General

Quality Assurance Other

While most of the site types are specific to a monitoring purpose, for example 

population exposure, two site types are general in nature and could be used for 

broad purposes (i.e., General and Other). States are encouraged not to use the 

general or other categories unless no other options are appropriate. U.S. EPA 

requires that a monitor be properly designated with an appropriate site type so 

that the data collected by the monitor at a site can be used to support the three 

basic federal monitoring objectives, which are discussed in more detail below. 

The site type of the monitors covered in this report is included in Table 3.

Federal Monitoring Objective

An ambient air monitoring network must be designed to meet three basic federal 

monitoring objectives, which are:

1) to provide air quality data to the public in a timely manner;

2) to support compliance with national air quality standards; and

3) to support air quality research studies.

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7 Annual Monitoring Network Report for Twenty-three Districts in California
For purposes of this report, the monitoring objectives are the federal monitoring 

objectives defined in Appendix D of 40 CFR 58. Federal monitoring regulations 

required that each monitor measuring criteria pollutants have at least one 

monitoring objective. However, many air quality agencies operate monitors with 

multiple objectives in mind. For example, monitoring is conducted to provide 

both air quality data to the public as well as to support air quality standards. The 

federal monitoring objective of the monitors covered in this report is included in 

Table 3.

Federal Monitor Type

U.S. EPA requires that every state establish a network of air monitoring stations 

for criteria pollutants, using criteria set in the CFR for the monitoring stations’

location and operation. The monitoring stations in this network are called the 

State and Local Air Monitoring Stations (SLAMS). In addition, U.S. EPA requires 

state and local monitoring agencies to establish monitoring stations to measure 

approximately 60 volatile hydrocarbons and carbonyls, which plays an integral 

role in ozone studies. These stations are called the Photochemical Assessment 

Monitoring Stations (PAMS). A third type of monitor, the Special Purpose Monitor 

(SPM), is used by state and local monitoring agencies to fulfill very specific or 

short-term monitoring goals. While there are a total of fifteen monitor types 

established by U.S. EPA, SLAMS, PAMS, and SPM are the three most common 

monitor types used by state and local monitoring agencies in California. Table 3 

lists the monitor type of each monitor that is covered in this report. All of the 

regulatory monitors included in this report are part of the SLAMS network in 

California. The completed list of monitor types is listed at the end of Table 3. 

State and Local Monitoring Purposes

There are a number of monitoring purposes besides the federal classifications. 

These are directly related to the needs of state and local agencies. California 

has a very comprehensive monitoring network that is needed for implementing a 

variety of programs. Listed below are some of the most common state and local

monitoring purposes:

• Agricultural Burning refers to the intentional use of fire for vegetation 

management, both in agricultural settings, such as fields and orchards, as 

well as in wildlands, including rangeland and forests, to improve land for 

wildlife and game habitat or as a tool for disease or pest prevention. 

Monitors with this purpose are used to assess when and where burning 

can occur.

• Expected High Concentration monitoring is used to measure pollutant 

concentrations in areas where air pollution is expected to be at its highest. 

The State designation criteria contain the requirement for this type of 

monitoring in order to show that an area attains the State air quality

standards. During the State area designation process, the data from all 

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8 Annual Monitoring Network Report for Twenty-three Districts in California
monitors in an area are examined, but only the data from the monitors with 

the highest concentrations will determine the designation of the area.

• The Geyser Air Monitoring Program (GAMP) was established to monitor 

ambient air quality in geothermal areas, mainly monitoring for hydrogen 

sulfide. 

• Residential Burning or backyard burning is the open burning of yard 

wastes by household residents. Backyard burning includes dry weeds, 

plant pruning, shrubbery, tree trimmings, and branches. Data from 

monitors with this purpose help guide decisions regarding appropriate 

times to allow residential burning.

• Representative Concentration means locating a site to represent a 

geographical region with common topography and meteorology. These 

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

a particular pollutant. This is a purpose also listed by the U.S. EPA.

• State Area Designation monitoring is used to determine compliance with 

the State ambient air quality standards for a particular pollutant. Using the 

monitors with the highest concentrations of a particular pollutant, the ARB 

determines if the area is in attainment or nonattainment of the State air 

quality standards, as already described in the discussion of Expected High 

Concentration Monitoring.

• State Implementation Plan (SIP) and/or Maintenance Plan Requirement is 

monitoring conducted to demonstrate compliance with SIP requirements. 

The SIP is a plan prepared by states and submitted to the U.S. EPA 

describing how each area will attain federal air quality standards. Once an 

area attains a standard, the area is required to show and maintain that 

status, which requires continued monitoring in the area. 

• Trend Analysis monitoring is useful for comparing and analyzing air 

pollution concentrations over time and distance. Usually, trend analyses 

show the progress or lack of progress in improving air quality for an area 

over a period of years. Some sites are more useful than others for trend 

analyses. For example, it is better to have a history of monitoring at a site 

that includes the full time period of a trend analysis.

This is not a comprehensive list of all state and local monitoring purposes, but 

only includes the most common purposes used for monitoring by air quality 

agencies in California. Note that the terms “objective” and “purpose” are almost 

analogous to one another and could be used interchangeably. However, to avoid 

confusion this report separates the monitoring objectives from the monitoring 

purposes by limiting the monitoring objectives to the three federal objectives as 

defined above and the monitoring purposes to the state and local monitoring 

purposes. The state and local monitoring purposes are more comprehensive

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9 Annual Monitoring Network Report for Twenty-three Districts in California
than the federal monitoring objectives. The state and local monitoring purpose of 

the monitors covered in this report is included in Table 3.

Summary of Table 3

Table 3 lists the federal site type, federal monitoring objective, federal monitor 

type, and state and local monitoring purposes of each monitor covered in this 

report. In addition, Table 3 lists other site and monitoring information, such as the 

AQS Site ID, site address, site name, pollutants monitored, and parameter 

codes. Note that the term “site type” refers to the individual monitor(s) at a site 

and not the site itself. U.S. EPA has determined that a single site type may not 

describe all of the monitors at a particular site; therefore, U.S. EPA established

the site type designations at the monitor level, rather than the site level. Also 

note that a monitor can have multiple site type, monitoring objective, monitor 

type, or monitoring purpose designations.

Finally, Table 3 also lists the location of each monitor, including the Core-Based 

Statistical Area (CBSA) in which the monitor is located. CBSAs are defined by 

the United States Office of Management and Budget (OMB) and provide a 

consistent set of geographical areas for Federal agencies to use in collecting, 

tabulating, and publishing statistical data. Two types of areas are included as 

CBSAs: Metropolitan Statistical Areas and Micropolitan Statistical Areas. The 

difference between a Metropolitan and Micropolitan statistical area is the level of 

population. A Metropolitan Statistical Area has an urban core with a population of 

50,000 or more, whereas a Micropolitan Statistical Area has an urban core with a 

population of at least 10,000, but less than 50,000. Both Metropolitan and 

Micropolitan statistical areas comprise one or more counties. 

U.S. EPA specifies the number of monitors required for each pollutant based on 

the OMB statistical areas. Older standards, such as the federal ozone standard, 

specify required monitors based on Metropolitan Statistical Area and Micropolitan 

Statistical Area. More recent standards, such as the federal SO2 standard, use 

the newer collective term, CBSA. Because it is more current, the term CBSA is 

used in this report, as well. A comprehensive CBSA list for California is provided

in Table 6a and Figure 2 of this report. Also in Table 6a is information about 

CBSAs that are not covered in this plan, but are covered either in part or in 

whole, in other individual district plans.

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10 Annual Monitoring Network Report for Twenty-three Districts in California
Table 3

Site and Monitoring Information

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Address/AQS Site # 44201 42101 42602 42401 88101 81102

LAKE COUNTY AIR BASIN

Lake County / CBSA: Clearlake Micropolitan Statistical Area

Middletown-Anderson Springs Road** Site Type: Gnrl

11270 Anderson Springs Road, Middletown Monitoring Obj.: RSupport

060333010 Monitoring Purp.: StateD, GAMP

Monitor Type: SLAMS

Glenbrook-High Valley Road** Site Type: Gnrl

8276 High Valley Road, Cobb Monitoring Obj.: RSupport

060333011 Monitoring Purp.: StateD, GAMP

Monitor Type: SLAMS

Lakeport-Lakeport Blvd** Site Type: Gnrl Gnrl Gnrl

905 Lakeport Blvd, Lakeport Monitoring Obj.: NAAQS NAAQS NAAQS

060333001 Monitoring Purp.: StateD StateD StateD

Monitor Type: SLAMS SLAMS SLAMS

LAKE TAHOE AIR BASIN

El Dorado County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

South Lake Tahoe-Sandy Way Site Type: (PopEx)

3337 Sandy Way, South Lake Tahoe Monitoring Obj.: (NAAQS/PublicR)

060170011 Monitoring Purp.: (RConc)

Monitor Type: (SLAMS)

MOJAVE DESERT AIR BASIN

Kern County / CBSA: Bakersfield Metropolitan Statistical Area

Canebrake-3147 Highway 178 Site Type: PopEx

3147 Highway 178, Canebrake Monitoring Obj.: NAAQS

060290017 Monitoring Purp.: RConc

Monitor Type: SLAMS

Mojave-923 Poole Street Site Type: HConc (PopEx) (PopEx)

923 Poole Street, Mojave Monitoring Obj.: NAAQS (NAAQS) (NAAQS)

060290011 Monitoring Purp.: SIPMain, Trans (StateD) (StateD)

Monitor Type: SLAMS (SLAMS) (SLAMS)

Ridgecrest-100 West California Avenue Site Type: PopEx PopEx

100 West California Avenue, Ridgecrest Monitoring Obj.: NAAQS NAAQS

060290015 Monitoring Purp.: StateD, RConc SIPMain, StateD

Monitor Type: SLAMS SLAMS

Los Angeles County / CBSA: Los Angeles-Long Beach-Anahiem Metropolitan Statistical Area

Lancaster-43301 Division Street Site Type: Trans Gnrl Gnrl HConc (Gnrl)

43301 Division Street, Lancaster Monitoring Obj.: NAAQS NAAQS NAAQS NAAQS (NAAQS/PublicR)

060379033 Monitoring Purp.: Trnds RConc RConc RConc (RConc)

Monitor Type: SLAMS SLAMS SLAMS SLAMS (SLAMS)

Riverside County / CBSA: Riverside-San Bernardino-Ontario Metropolitan Statistical Area

Blythe-445 W Murphy Street Site Type: Gnrl

445 W Murphy Street, Blythe Monitoring Obj.: NAAQS/PublicR

060659003 Monitoring Purp.: RConc

Monitor Type: SLAMS

San Bernardino County / CBSA: Riverside-San Bernardino-Ontario Metropolitan Statistical Area

Barstow-200 E Buena Vista Road Site Type: Trans Gnrl Gnrl (Gnrl)

200 E Buena Vista Road, Barstow Monitoring Obj.: NAAQS NAAQS NAAQS (NAAQS)

060710001 Monitoring Purp.: StateD StateD StateD (StateD)

Monitor Type: SLAMS SLAMS SLAMS (SLAMS)

Hesperia-Olive Street Site Type: Trans (Gnrl)

17288 Olive Street, Hesperia Monitoring Obj.: NAAQS (NAAQS)

060714001 Monitoring Purp.: StateD (StateD)

Monitor Type: SLAMS (SLAMS)

Table 3 (cont.)

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11 Annual Monitoring Network Report for Twenty-three Districts in California
Site and Monitoring Information

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Address/AQS Site # 44201 42101 42602 42401 88101 81102

Joshua Tree National Mont.-Black Rock Site Type: PopEx

060719002 Monitoring Obj.: NAAQS/PublicR

Monitoring Purp.: RConc

Monitor Type: SLAMS

Lucerne Valley-Middle School Site Type: Gnrl

8560 Aliento-Middle School, Lucerne Valley Monitoring Obj.: NAAQS

060710013 Monitoring Purp.: StateD

Monitor Type: SLAMS

Phelan-Beekley and Phelan Roads Site Type: Trans

Beekley Road and Phelan Road, Phelan Monitoring Obj.: NAAQS

060710012 Monitoring Purp.: StateD

Monitor Type: SLAMS

Trona-Athol and Telescope Site Type: Gnrl Gnrl Gnrl (HConc)

Corner of Athol and Telescope, Trona Monitoring Obj.: NAAQS NAAQS NAAQS (NAAQS)

060711234 Monitoring Purp.: StateD StateD StateD (StateD)

Monitor Type: SLAMS SLAMS SLAMS (SLAMS)

Victorville-14036 Park Avenue Site Type: Trans Gnrl Gnrl Gnrl Gnrl (PopEx)

14036 Park Avenue, Victorville Monitoring Obj.: NAAQS NAAQS NAAQS NAAQS NAAQS (NAAQS)

060710306 Monitoring Purp.: StateD StateD StateD StateD StateD (StateD)

Monitor Type: SLAMS SLAMS SLAMS SLAMS SLAMS (SLAMS)

MOUNTAIN COUNTIES AIR BASIN

Amador County / Not in a CBSA

Jackson-201 Clinton Road Site Type: Gnrl/Trans

201 Clinton Road, Jackson Monitoring Obj.: NAAQS

060050002 Monitoring Purp.: StateD/SIPMain

Monitor Type: SLAMS

Calaveras County / Not in a CBSA

San Andreas-501 Gold Strike Road Site Type: Gnrl/Trans (Gnrl) Gnrl

501 Gold Strike Road, San Andreas Monitoring Obj.: NAAQS (NAAQS/PublicR) NAAQS

060090001 Monitoring Purp.: StateD/SIPMain (RConc) StateD

Monitor Type: SLAMS (SPM) SLAMS

El Dorado County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Cool-Highway 193 Site Type: HConc

1400 American River Trail, Cool Monitoring Obj.: NAAQS

060170020 Monitoring Purp.: SIPMain

Monitor Type: SLAMS

Echo Summit Site Type: Trans

21200 Highway 50-Little Norway Monitoring Obj.: NAAQS

060170012 Monitoring Purp.: StateD

Monitor Type: SLAMS

Placerville-Gold Nugget Way Site Type: HConc/Trans

3111 Gold Nugget Way, Placerville Monitoring Obj.: NAAQS

060170010 Monitoring Purp.: StateD

Monitor Type: SLAMS

Mariposa County / Not in a CBSA

Jerseydale-6440 Jerseydale Site Type: Trans

6440 Jerseydale Road, Jerseydale Monitoring Obj.: NAAQS

060430006 Monitoring Purp.: StateD

Monitor Type: SLAMS

Yosemite National Park-Turtleback Dome Site Type: HConc/Trans

060430003 Monitoring Obj.: NAAQS

Monitoring Purp.: StateD

Monitor Type: SLAMS

Yosemite Village-Visitor Center Site Type: Gnrl

060431001 Monitoring Obj.: NAAQS

Monitoring Purp.: StateD

Monitor Type: SLAMS

Table 3 (cont.)

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12 Annual Monitoring Network Report for Twenty-three Districts in California
Site and Monitoring Information

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Address/AQS Site # 44201 42101 42602 42401 88101 81102

Nevada County / CBSA: Truckee-Grass Valley Micropolitan Statistical Area

Grass Valley-Litton Building Site Type: HConc/Trans PopEx

200 Litton Drive, Grass Valley Monitoring Obj.: NAAQS NAAQS

060570005 Monitoring Purp.: StateD/Trnds StateD

Monitor Type: SLAMS SLAMS

Truckee-Fire Station Site Type: Hconc

10049 Donner Pass Road, Truckee Monitoring Obj.: NAAQS

060571001 Monitoring Purp.: StateD

Monitor Type: SLAMS

White Cloud Mountain Site Type: Gnrl

26533 State Highway 20, White Cloud Mtn. Monitoring Obj.: NAAQS

060570007 Monitoring Purp.: StateD

Monitor Type: SLAMS

Placer County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Colfax-City Hall Site Type: Gnrl Gnrl

33 South Main Street, Colfax Monitoring Obj.: NAAQS NAAQS

060610004 Monitoring Purp.: StateD StateD

Monitor Type: SLAMS SLAMS

Plumas County / Not in a CBSA

Portola-420 N Gulling St Site Type: HConc

420 N Gulling Street, Portola Monitoring Obj.: NAAQS

060631010 Monitoring Purp.: StateD

Monitor Type: SLAMS

Quincy-N Church Street Site Type: Hconc

267 North Church Street, Quincy Monitoring Obj.: NAAQS

060631006 Monitoring Purp.: StateD

Monitor Type: SLAMS

Tuolumne County / CBSA: Phoenix Lake-Cedar Ridge Micropolitan Statistical Area

Sonora-Barretta Street Site Type: Gnrl

251 South Barretta Street, Sonora Monitoring Obj.: NAAQS

061090005 Monitoring Purp.: StateD/SIPMain

Monitor Type: SLAMS

NORTH COAST AIR BASIN

Mendocino County / CBSA: Ukiah Micropolitan Statistical Area

Fort Bragg-Dana Street Site Type: (Gnrl)

300 Dana Street, Fort Bragg Monitoring Obj.: (NAAQS)

060450010 Monitoring Purp.: (RConc)

Monitor Type: (SLAMS)

Ukiah-County Library Site Type: (Gnrl)

105 North Main Street, Ukiah Monitoring Obj.: (NAAQS)

060450006 Monitoring Purp.: (RConc)

Monitor Type: (SLAMS)

Ukiah-East Gobbi Street Site Type: Trans

306 East Gobbi Street, Ukiah Monitoring Obj.: NAAQS

060450008 Monitoring Purp.: StateD

Monitor Type: SLAMS

Willits-125 East Commercial Street Site Type: (Gnrl)

125 East Commercial Street, Willits Monitoring Obj.: (NAAQS)

060452002 Monitoring Purp.: (RConc)

Monitor Type: (SLAMS)

Sonoma County / CBSA: Santa Rosa Metropolitan Statistical Area

Cloverdale-100 Washington Street Site Type: Gnrl

100 Washington Street, Colverdale Monitoring Obj.: NAAQS

060970001 Monitoring Purp.: AgBn, ResBn

Monitor Type: SLAMS

Guerneville-Church and 1st Site Type: Gnrl

16255 1st Street, Guerneville Monitoring Obj.: NAAQS

060973002 Monitoring Purp.: AgBn, ResBn

Monitor Type: SLAMS

Table 3 (cont.)

_______________________________________________________________________

13 Annual Monitoring Network Report for Twenty-three Districts in California
Site and Monitoring Information

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Address/AQS Site # 44201 42101 42602 42401 88101 81102

Healdsburg-133 Matheson Street Site Type: HConc

133 Matheson Street, Healdsburg Monitoring Obj.: NAAQS

060970002 Monitoring Purp.: AgBn, ResBn

Monitor Type: SLAMS

Healdsburg-Municipal Airport Site Type: Gnrl

200a Heidelberg Way, Healdsburg Monitoring Obj.: NAAQS

060971003 Monitoring Purp.: StateD

Monitor Type: SLAMS

NORTHEAST PLATEAU AIR BASIN

Siskiyou County / Not in a CBSA

Yreka-Foothill Drive Site Type: Gnrl/Trans Gnrl Gnrl

528 Foothill Drive, Yreka Monitoring Obj.: NAAQS/PublicR NAAQS NAAQS

060932001 Monitoring Purp.: StateD StateD AgBn/StateD

Monitor Type: SLAMS SLAMS SLAMS

SACRAMENTO VALLEY AIR BASIN

Butte County / CBSA: Chico Metropolitan Statistical Area

Chico-East Site Type: Gnrl Gnrl Gnrl HConc HConc

984 East Avenue, Chico Monitoring Obj.: NAAQS NAAQS NAAQS NAAQS NAAQS

060070008 Monitoring Purp.: StateD/AgBn StateD StateD StateD StateD/AgBn

Monitor Type: SLAMS SLAMS SLAMS SLAMS SLAMS

Paradise-4405 Airport Road Site Type: Gnrl/HConc

4405 Airport Road, Paradise Monitoring Obj.: NAAQS

060070007 Monitoring Purp.: StateD/AgBn

Monitor Type: SLAMS

Colusa County/ Not in a CBSA 

Colusa-Sunrise Blvd Site Type: Gnrl Gnrl Gnrl

100 Sunrise Blvd, Colusa Monitoring Obj.: NAAQS NAAQS NAAQS

060111002 Monitoring Purp.: StateD/AgBn StateD StateD/AgBn

Monitor Type: SLAMS SLAMS SLAMS

Glenn County / Not in a CBSA

Willows-Colusa Street Site Type: Gnrl (Gnrl)

720 N Colusa Street, Willows Monitoring Obj.: NAAQS (NAAQS)

060210003 Monitoring Purp.: StateD/AgBn (StateD/AgBn)

Monitor Type: SLAMS (SLAMS)

Placer County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Auburn-Atwood Site Type: Gnrl (Gnrl)

11645 Atwood Road, Auburn Monitoring Obj.: NAAQS (NAAQS)

060610003 Monitoring Purp.: StateD (StateD)

Monitor Type: SLAMS (SLAMS)

Auburn-B Avenue Site Type: Gnrl

11464 B Ave, Auburn Monitoring Obj.: NAAQS

060610002 Monitoring Purp.: StateD

Monitor Type: SLAMS

Lincoln-1st Street Site Type: Gnrl

1445 1st Street, Lincoln Monitoring Obj.: NAAQS

060612002 Monitoring Purp.: StateD

Monitor Type: SLAMS

Tahoe City Site Type: Gnrl

221 Fairway Drive, Tahoe City Monitoring Obj.: NAAQS

060611004 Monitoring Purp.: StateD

Monitor Type: SLAMS

Roseville-N Sunrise Blvd Site Type: Gnrl Gnrl Trans Gnrl

151 N Sunrise Blvd, Roseville Monitoring Obj.: NAAQS NAAQS NAAQS NAAQS

060610006 Monitoring Purp.: StateD/AgBn StateD StateD StateD/AgBn

Monitor Type: SLAMS SLAMS SLAMS SLAMS

Table 3 (cont.)

_______________________________________________________________________

14 Annual Monitoring Network Report for Twenty-three Districts in California
Site and Monitoring Information

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Address/AQS Site # 44201 42101 42602 42401 88101 81102

Shasta County / CBSA: Redding Metropolitan Statistical Area

Anderson-North Street Site Type: Gnrl HConc

2220 North Street, Anderson Monitoring Obj.: NAAQS NAAQS

060890007 Monitoring Purp.: StateD StateD

Monitor Type: SLAMS SLAMS

Lassen Volcanic Natl Park-Manzanita Lake Site Type: Gnrl

060893003 Monitoring Obj.: NAAQS

Monitoring Purp.: StateD

Monitor Type: SLAMS

Redding-Health Department Roof*** Site Type: Gnrl HConc Gnrl

2630 Hospital Lane, Redding Monitoring Obj.: NAAQS NAAQS NAAQS

060890004 Monitoring Purp.: StateD StateD StateD

Monitor Type: SLAMS SLAMS SLAMS

Shasta Lake-13791 Lake Blvd Site Type: HConc

13791 Lake Blvd, Shasta Lake Monitoring Obj.: NAAQS

060890009 Monitoring Purp.: StateD

Monitor Type: SLAMS

Shasta Lake-4066 La Mesa Avenue Site Type: Gnrl

4066 La Mesa Avenue, Shasta Lake Monitoring Obj.: NAAQS

060890008 Monitoring Purp.: StateD

Monitor Type: SLAMS

Solano County / CBSA: Vallejo-Fairfield Metropolitan Statistical Area

Vacaville-Merchant Street Site Type: HConc

650 Merchant Street, Vacaville Monitoring Obj.: NAAQS

060953001 Monitoring Purp.: StateD

Monitor Type: SLAMS

Vacaville-Ulatis Drive Site Type: Gnrl

2012 Ulatis Drive, Vacaville 060953003 Monitoring Obj.: o to g u p NAAQS State

Monitor Type: SLAMS

Sutter County / CBSA: Yuba City Metropolitan Statistical Area

Sutter Buttes-S Buttes Site Type: HConc/Trans

061010004 Monitoring Obj.: NAAQS

Monitoring Purp.: AgBn

Monitor Type: SLAMS

Yuba City-Almond Street Site Type: HConc Gnrl HConc HConc

773 Almond Street, Yuba City Monitoring Obj.: NAAQS NAAQS NAAQS NAAQS

061010003 Monitoring Purp.: StateD/AgBn StateD StateD StateD

Monitor Type: SLAMS SLAMS SLAMS SLAMS

Tehama County / CBSA: Red Bluff Micropolitan Statistical Area

Red Bluff-Main Street Site Type: (Gnrl)

301 S Main Street, Red Bluff Monitoring Obj.: (NAAQS)

061030006 Monitoring Purp.: (RConc)

Monitor Type: (SLAMS)

Red Bluff-Oak Street Site Type: Gnrl

502 Oak Street, Red Bluff Monitoring Obj.: NAAQS

061030005 Monitoring Purp.: StateD

Monitor Type: SLAMS

Red Bluff-Messer Drive Site Type: Gnrl

700 Messer Drive, Red Bluff Monitoring Obj.: NAAQS

061030002 Monitoring Purp.: StateD

Monitor Type: SLAMS

Tuscan Butte Site Type: Gnrl/Trans

061030004 Monitoring Obj.: NAAQS

Monitoring Purp.: StateD

Monitor Type: SLAMS

Table 3 (cont.)

_______________________________________________________________________

15 Annual Monitoring Network Report for Twenty-three Districts in California
Site and Monitoring Information

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Address/AQS Site # 44201 42101 42602 42401 88101 81102

Yolo County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Davis-UCD Campus Site Type: Gnrl Gnrl

061130004 Monitoring Obj.: NAAQS NAAQS

Monitoring Purp.: StateD/AgBn StateD

Monitor Type: SLAMS SLAMS

West Sacramento-15th Street Site Type: Gnrl

132 15th Street, West Sacramento Monitoring Obj.: NAAQS

061132001 Monitoring Purp.: StateD

Monitor Type: SLAMS

Woodland-Gibson Road Site Type: Gnrl PopEx Gnrl

41929 E Gibson Road, Woodland Monitoring Obj.: NAAQS NAAQS NAAQS

061131003 Monitoring Purp.: StateD StateD StateD/AgBn

Monitor Type: SLAMS SLAMS SLAMS

Notes:

This table only lists sites and monitors that have reported data in 2013. Lead monitors are not included 

in this list because there is no lead monitoring in the areas included in this report.

After a county name, the table lists the U.S. Office of Management and Budget's Core-Based Statistical 

Area (CBSA) that includes the county. The term CBSA includes both Metropolitan Statistical Areas and 

Micropolitan Statistical Areas. A Metropolitan Statistical Area has at least one urban area with a 

population of 50,000 or more. A Micropolitan Statistical Area has at least one urban area with a 

population of 10,000 to less than 50,000.

*Monitoring information inside a parenthesis ( ) in a PM column denotes that a continuous PM FEM 

monitor is located at the site. Monitoring information without a parenthesis reflects the filter-based PM

FRM monitor.

**The filter-based PM10 FRM monitors at the Middletown, Glenbrook and Lakeport sites located in 

Lake County are reporting PM10 data in local conditions (i.e., 85101) and not in standard temperature 

and pressure (i.e., 81102). 

***In addition to the Redding-Health Department site (060890004), there are also the Redding-Toyon 

and Redding-Buckeye sites located in the City of Redding. The Redding-Toyon and Redding-Buckeye 

sites are non-regulatory sites.

_______________________________________________________________________

16 Annual Monitoring Network Report for Twenty-three Districts in California
Codes used in Table 3

ExDwn Extreme downwind

HConc Highest concentration

MaxO3 Max ozone concentration

MaxEm Max precursor emmissions impact

PopEx Population Exposure

Sourc Source oriented

UpWin Upwind background

Gnrl General/Background

Trans Regional transport

Welf Welfare related impacts

QA Quality Assurance

Other Other

Federal Monitoring Objectives

PublicR Provide air pollution data to public in a timely manner

NAAQS NAAQS comparison

RSupport Research support

EHConc Monitoring at expected high concentration sites relative to

 California Ambient Air Quality Standards

RConc Representative concentrations

AgBn Support agricultural/prescribed burn decisions

ResBn Support residential burn program

Trnds Trends analysis

StateD Support State area designation

SIPMain State Implementation Plan (SIP) maintance requirement

GAMP Geyser Air Monitoring Program

Monitor Types

Impr Improve

Indx Index site

Indus Industrial

NATTS NATTS

NonEPA Non-EPA federal

NonReg Non-regulatory

PAMS PAMS

NCore Proposed Ncore

QAcoll QA collocated

SLAMS SLAMS

SPM Special purpose

SupSP Supplemental speciation

TrnSP Trends speciation

Tribal Tribal monitors

UnPAMS Unofficial PAMS

Monitoring Purposes

Site Types

 

_______________________________________________________________________

17 Annual Monitoring Network Report for Twenty-three Districts in California
Section 4. Additional Information about the Monitors

U.S. EPA regulations require that the annual network plan list specific additional 

information about the monitors that characterize the nature and location of the 

monitoring. Table 4 lists the spatial scales, sampling methods, method codes, 

parameter occurrence codes (POC) and start dates of the monitors that are 

included in this report. Also included in Table 4 are the geographical coordinates 

of the monitoring sites. Note that the continuous PM FEM monitors are listed in 

parenthesis in the PM columns in Table 4. At the end of Table 4, the codes used 

for the spatial scales, sampling methods, and method codes are defined as well 

as a brief explanation of the POC.

The regulations also require that the annual network plan list the laboratory 

analysis methods of the monitors. However, there is no separate analysis 

method for the gaseous monitors and continuous PM monitors. For the 

filter-based PM monitors, only simple mass weighing is done. Moreover, the 

regulations require that the network plan include distance from road information,

groundcover of the monitoring sites, probe heights of the monitoring instruments, 

materials used for monitoring, and distance from obstructions information. 

The monitoring information for groundcover, distance from road/obstruction, 

probe heights and monitoring instrument/material is not included at this time. 

Previous network plans included this information; however, U.S. EPA determined 

that some of the information was inadequate and needs to be updated. For this 

reason, U.S. EPA, ARB, districts, and a contractor are in the process of 

developing a statewide database to collect and store current site and monitoring 

information for all of the monitoring sites in California. Once this database is 

complete, which is anticipated to be available for use in 2015, this required site 

and monitoring information will be included in the ARB network plan. In the 

interim, older information can be viewed via ARB’s site surveys at: 

www.arb.ca.gov/qaweb/site.php.

Finally, additional information on continuous PM2.5 non-FEM monitors is provided

on page 26 and in Table 5.

_______________________________________________________________________

18 Annual Monitoring Network Report for Twenty-three Districts in California
Table 4

Additional Information about the Monitors

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Geographical Coordinates/AQS Site # 44201 42101 42602 42401 88101 81102

LAKE COUNTY AIR BASIN

Lake County / CBSA: Clearlake Micropolitan Statistical Area

Middletown-Anderson Springs Road** Spatial Scale: NGH

38.7744, -122.6994 Samp. Method: SCH, XG

060333010 Mthd. Code/POC: 098 / 1

Start Date: 1-1-2005

Glenbrook-High Valley Road** Spatial Scale: NGH

38.8502, -122.7361 Samp. Method: SCH, XG

060333011 Mthd. Code/POC: 098 / 1

Start Date: 1-1-2005

Lakeport-Lakeport Blvd** Spatial Scale: URB URB URB

39.0330, -122.9219 Samp. Method: UV SCH SCH

060333001 Mthd. Code/POC: 087 / 1 117 / 1 098 / 2

Start Date: 1-1-1980 1-1-1999 4-1-2001

LAKE TAHOE AIR BASIN

El Dorado County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

South Lake Tahoe-Sandy Way Spatial Scale: (NGH)

38.9450, -119.9703 Samp. Method: (BAM)

060170011 Mthd. Code/POC: (122 / 2)

Start Date: (6-1-2001)

MOJAVE DESERT AIR BASIN

Kern County / CBSA: Bakersfield Metropolitan Statistical Area

Canebrake-3147 Highway 178 Spatial Scale: REG

35.7277, -118.1393 Samp. Method: SI

060290017 Mthd. Code/POC: 141 / 1

Start Date: 1/1/2009

Mojave-923 Poole Street Spatial Scale: REG (NGH) (REG)

35.0503, -118.1478 Samp. Method: UV (BAM) (BAM)

060290011 Mthd. Code/POC: 087 / 1 (170 / 3) (122 / 3)

Start Date: 8-1-1993 (4-1-2011) (4-1-2011)

Ridgecrest-100 West California Avenue Spatial Scale: NGH NGH

35.6211, -117.6731 Samp. Method: SI SI 

060290015 Mthd. Code/POC: 118 / 1 063 / 1

Start Date: 6-1-1999 12-15-1999

Los Angeles County / CBSA: Los Angeles-Long Beach-Anahiem Metropolitan Statistical Area

Lancaster-43301 Division Street Spatial Scale: MID MID MID NGH (NGH)

34.6713, -118.1305 Samp. Method: UV IR CL SQ (BAM)

060379033 Mthd. Code/POC: 087 / 1 093 / 1 099 / 1 117 / 1 (122 / 2)

Start Date: 11-1-2001 11-1-2001 11-1-2001 11-1-2001 (11-1-01)

Riverside County / CBSA: Riverside-San Bernardino-Ontario Metropolitan Statistical Area

Blythe-445 W Murphy Street Spatial Scale: NGH

33.6119, -114.6000 Samp. Method: UV

060659003 Mthd. Code/POC: 087 / 1

Start Date: 5-1-2003

San Bernardino County / CBSA: Riverside-San Bernardino-Ontario Metropolitan Statistical Area

Barstow-200 E Buena Vista Road Spatial Scale: NGH NGH NGH (NGH)

34.8938, -117.0244 Samp. Method: UV IR CL (BAM)

060710001 Mthd. Code/POC: 087 / 1 093 / 1 099 / 1 (122/ 1)

Start Date: 1-1-1974 1-1-1973 1-1-1973 (1-1-2014)

Hesperia-Olive Street Spatial Scale: NGH (NGH)

34.4158, -117.2861 Samp. Method: UV (BAM)

060714001 Mthd. Code/POC: 087 / 1 (122/1)

Start Date: 1-1-1980 (1-1-2014)

_______________________________________________________________________

19 Annual Monitoring Network Report for Twenty-three Districts in California
Table 4 (cont.)

Additional Information about the Monitors

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Geographical Coordinates/AQS Site # 44201 42101 42602 42401 88101 81102

Joshua Tree National Mont.-Black Rock Spatial Scale: REG

34.0694, -116.3888 Samp. Method: UV

060719002 Mthd. Code/POC: 047 / 1

Start Date: 10/1/1993

Lucerne Valley-Middle School Spatial Scale: NGH

34.4103, -116.9067 Samp. Method: SI

060710013 Mthd. Code/POC: 063 / 1

Start Date: 6-1-1989

Phelan-Beekley and Phelan Roads Spatial Scale: NGH

34.4250, -117.5897 Samp. Method: UV

060710012 Mthd. Code/POC: 087 / 1

Start Date: 7-1-1987

Trona-Athol and Telescope Spatial Scale: REG NGH REG (NGH)

35.7744, -117.3722 Samp. Method: UV CL FL (BAM)

060711234 Mthd. Code/POC: 087 / 1 099 / 1 077 / 1 (122/ 2)

Start Date: 4-1-1997 4-1-1997 4-1-1997 (1-1-2013)

Victorville-14036 Park Avenue Spatial Scale: NGH NGH NGH NGH NGH (NGH)

34.5122, -117.3250 Samp. Method: UV IR CL FL SQ (BAM)

060710306 Mthd. Code/POC: 087 / 1 093 / 1 099 / 1 077 / 1 117 / 1 (122 / 2)

Start Date: 1-1-2000 1-1-2000 1-1-2000 1/1/2000 1-1-2000 (1-1-2013)

MOUNTAIN COUNTIES AIR BASIN

Amador County / Not in a CBSA

Jackson-201 Clinton Road Spatial Scale: URB

38.3427, -120.7644 Samp. Method: UV

060050002 Mthd. Code/POC: 087 / 1

Start Date: 5-1-1992

Calaveras County / Not in a CBSA

San Andreas-501 Gold Strike Road Spatial Scale: REG (REG) REG

38.2019, -120.6802 Samp. Method: UV (BAM) SI

060090001 Mthd. Code/POC: 087 / 1 (170 / 3) 063 / 1

Start Date: 5-1-1994 (6-15-2010) 4-1-1994

El Dorado County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Cool-Highway 193 Spatial Scale: REG

38.8906, -121.0000 Samp. Method: UV

060170020 Mthd. Code/POC: 087 / 1

Start Date: 6-1-1996

Echo Summit Spatial Scale: REG

38.8117, -120.0331 Samp. Method: UV

060170012 Mthd. Code/POC: 087 / 1

Start Date: 5-7-2006

Placerville-Gold Nugget Way Spatial Scale: REG

38.7247, -120.8219 Samp. Method: UV

060170010 Mthd. Code/POC: 087 / 1

Start Date: 2-1-1992

Mariposa County / Not in a CBSA

Jerseydale-6440 Jerseydale Spatial Scale: REG

37.5466, -119.8416 Samp. Method: UV

060430006 Mthd. Code/POC: 087 / 1

Start Date: 7-1-1995

Yosemite National Park-Turtleback Dome Spatial Scale: REG

37.7133, -119.7058 Samp. Method: UV

060430003 Mthd. Code/POC: 047 / 1

Start Date: 11-1-1988

Yosemite Village-Visitor Center Spatial Scale: NGH

37.7486, -119.5869 Samp. Method: SI

060431001 Mthd. Code/POC: 063 / 2

Start Date: 1-28-1989

_______________________________________________________________________

20 Annual Monitoring Network Report for Twenty-three Districts in California
Table 4 (cont.)

Additional Information about the Monitors

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Geographical Coordinates/AQS Site # 44201 42101 42602 42401 88101 81102

Nevada County / CBSA: Truckee-Grass Valley Micropolitan Statistical Area

Grass Valley-Litton Building Spatial Scale: URB NGH

39.2336, -121.0555 Samp. Method: UV SCH

060570005 Mthd. Code/POC: 087 / 1 117 / 1

Start Date: 6-1-1993 12-30-98

Truckee-Fire Station Spatial Scale: NGH

39.3274, -120.1847 Samp. Method: SQ

060571001 Mthd. Code/POC: 118 / 1

Start Date: 3-31-99

White Cloud Mountain Spatial Scale: REG

39.3181, -120.8456 Samp. Method: UV

060570007 Mthd. Code/POC: 087 / 1

Start Date: 6-1-1995

Placer County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Colfax-City Hall Spatial Scale: URB NGH

39.0997, -120.9541 Samp. Method: UV SI

060610004 Mthd. Code/POC: 087 / 1 063 / 1

Start Date: 1-1-1992 1-1-2012

Plumas County / Not in a CBSA

Portola-420 N Gulling St Spatial Scale: NGH

39.8133, -120.4707 Samp. Method: SCH

060631010 Mthd. Code/POC: 118 / 1

Start Date: 1-18-07

Quincy-N Church Street Spatial Scale: NGH

39.9397, -120.9441 Samp. Method: SQ

060631006 Mthd. Code/POC: 118 / 1

Start Date: 3-26-99

Tuolumne County / CBSA: Phoenix Lake-Cedar Ridge Micropolitan Statistical Area

Sonora-Barretta Street Spatial Scale: NGH

37.9819, -120.3786 Samp. Method: UV

061090005 Mthd. Code/POC: 087 / 1

Start Date: 7-1-1992

NORTH COAST AIR BASIN

Mendocino County / CBSA: Ukiah Micropolitan Statistical Area

Fort Bragg-Dana Street Spatial Scale: (NGH)

39.4373, -123.7877 Samp. Method: (BAM)

060450010 Mthd. Code/POC: (122 / 1)

Start Date: (8-17-2011)

Ukiah-County Library Spatial Scale: (NGH)

39.1511, -123.2066 Samp. Method: (BAM)

060450006 Mthd. Code/POC: (170 / 3)

Start Date: (12-31-2008)

Ukiah-East Gobbi Street Spatial Scale: URB

39.1447, -123.2002 Samp. Method: UV

060450008 Mthd. Code/POC: 087 / 1

Start Date: 8-1-1992

Willits-125 East Commercial Street Spatial Scale: (NGH)

39.4118, -123.3528 Samp. Method: (BAM)

060452002 Mthd. Code/POC: (170 / 3)

Start Date: (9-15-2009)

Sonoma County / CBSA: Santa Rosa Metropolitan Statistical Area

Cloverdale-100 Washington Street Spatial Scale: NGH

38.8047, -123.0177 Samp. Method: SI

060970001 Mthd. Code/POC: 063 / 2

Start Date: 1-1-1990

Guerneville-Church and 1st Spatial Scale: NGH

38.5016, -122.9977 Samp. Method: SI

060973002 Mthd. Code/POC: 063 / 1

Start Date: 4-1-1990

Table 4 (cont.)

_______________________________________________________________________

21 Annual Monitoring Network Report for Twenty-three Districts in California
Additional Information about the Monitors

(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Geographical Coordinates/AQS Site # 44201 42101 42602 42401 88101 81102

Healdsburg-133 Matheson Street Spatial Scale: NGH

38.6111, -122.8686 Samp. Method: SI

060970002 Mthd. Code/POC: 063 / 2

Start Date: 5-21-1988

Healdsburg-Municipal Airport Spatial Scale: URB

38.6536, -122.9005 Samp. Method: UV

060971003 Mthd. Code/POC: 087 / 1

Start Date: 6-1-1991

NORTHEAST PLATEAU AIR BASIN

Siskiyou County / Not in a CBSA

Yreka-Foothill Drive Spatial Scale: NGH NGH NGH

41.7267, -122.6336 Samp. Method: UV SQ SI

060932001 Mthd. Code/POC: 087 / 1 117 / 1 063 / 2

Start Date: 1-1-1981 8-21-2008 1-1-1988

SACRAMENTO VALLEY AIR BASIN

Butte County / CBSA: Chico Metropolitan Statistical Area

Chico-East Spatial Scale: URB NGH NGH NGH NGH

39.7616, -121.8405 Samp. Method: UV IR CL SCH SI

060070008 Mthd. Code/POC: 087 / 1 593 / 1 099 / 3 118 / 1 063 / 1

Start Date: 6-1-2012 6-1-2012 6-8-2012 4-27-12 5-27-2012

Paradise-4405 Airport Road Spatial Scale: REG

39.7141, -121.6177 Samp. Method: UV

060070007 Mthd. Code/POC: 087 / 1

Start Date: 5-1-2000

Colusa County / Not in a CBSA 

Colusa-Sunrise Blvd Spatial Scale: REG NGH REG

39.1888, -121.9980 Samp. Method: UV SQ SI

060111002 Mthd. Code/POC: 087 / 1 118 / 1 063 / 2

Start Date: 7-1-1996 12-16-98 5-1-1988

Glenn County / Not in a CBSA

Willows-Colusa Street Spatial Scale: URB (REG)

39.5172, -122.1897 Samp. Method: UV (BAM)

060210003 Mthd. Code/POC: 087 / 1 (122/1)

Start Date: 9-13-2006 (10-1-2013)

Placer County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Auburn-Atwood Spatial Scale: URB (NGH)

38.9356, -121.0995 Samp. Method: UV (BAM)

060610003 Mthd. Code/POC: 087 / 1 (170 / 1)

Start Date: 6-24-2011 (6-24-2011)

Auburn-B Avenue Spatial Scale: NGH

38.9394, -121.1055 Samp. Method: SI

060610002 Mthd. Code/POC: 063 / 1 

Start Date: 1-1-2012

Lincoln-1st Street Spatial Scale: URB

38.8856, -121.3020 Samp. Method: UV

060612002 Mthd. Code/POC: 087 / 1

Start Date: 12-21-2012

Tahoe City Spatial Scale: URB

39.1660, -120.1488 Samp. Method: UV

060611004 Mthd. Code/POC: 087 / 1

Start Date: 11-1-2013

Roseville-N Sunrise Blvd Spatial Scale: URB NGH NGH URB

38.7461, -121.2647 Samp. Method: UV CL SCH SI

060610006 Mthd. Code/POC: 087 / 1 099 / 1 117 / 1 063 /1

Start Date: 1-13-1993 1-13-1993 12-31-98 1-13-1993

Table 4 (cont.)

Additional Information about the Monitors

_______________________________________________________________________

22 Annual Monitoring Network Report for Twenty-three Districts in California
(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Geographical Coordinates/AQS Site # 44201 42101 42602 42401 88101 81102

Shasta County / CBSA: Redding Metropolitan Statistical Area

Anderson-North Street Spatial Scale: NGH NGH

40.4531, -122.2986 Samp. Method: UV SI

060890007 Mthd. Code/POC: 087 / 1 063 / 1

Start Date: 5-1-1993 5-1-1993

Lassen Volcanic Natl Park-Manzanita Lake Spatial Scale: REG

40.5372, -121.5764 Samp. Method: UV

060893003 Mthd. Code/POC: 047 / 1

Start Date: 11-1-1987

Redding-Health Department Roof*** Spatial Scale: NGH NGH NGH

40.5514, -122.3808 Samp. Method: UV SCH SI

060890004 Mthd. Code/POC: 087 / 1 117 / 1 063 / 2

Start Date: 5-1-1990 12-19-1998 1-1-1988

Shasta Lake-13791 Lake Blvd Spatial Scale: NGH

40.6894, -122.4011 Samp. Method: UV

060890009 Mthd. Code/POC: 087 / 1

Start Date: 4-1-2009

Shasta Lake-4066 La Mesa Avenue Spatial Scale: REG

40.6775, -122.3733 Samp. Method: SI

060890008 Mthd. Code/POC: 063 / 1

Start Date: 1-1-2004

Solano County / CBSA: Vallejo-Fairfield Metropolitan Statistical Area

Vacaville-Merchant Street Spatial Scale: URB

38.3516, -121.9933 Samp. Method: SI

060953001 Mthd. Code/POC: 063 / 2

Start Date: 1-1-1988

Vacaville-Ulatis Drive Spatial Scale: URB

38.3583, -121.9500 Samp. Method: UV

060953003 Mthd. Code/POC: 087 / 1

Start Date: 7-21-2003

Sutter County / CBSA: Yuba City Metropolitan Statistical Area

Sutter Buttes-S Buttes Spatial Scale: REG

39.1583, -121.7500 Samp. Method: UV

061010004 Mthd. Code/POC: 087 / 1

Start Date: 5-1-1993

Yuba City-Almond Street Spatial Scale: URB NGH NGH NGH

39.1388, -121.6191 Samp. Method: UV CL SCH SI

061010003 Mthd. Code/POC: 087 / 1 099 / 1 118 / 1 063 / 1

Start Date: 10-1-1989 10-1-1989 12-19-98 12-1-1989

Tehama County / CBSA: Red Bluff Micropolitan Statistical Area

Red Bluff-Main Street Spatial Scale: (NGH)

40.1678, -122.2271 Samp. Method: (BAM)

061030006 Mthd. Code/POC: (170 / 3)

Start Date: (1-1-2009)

Red Bluff-Oak Street Spatial Scale: URB

40.1749, -122.2366 Samp. Method: UV

061030005 Mthd. Code/POC: 087 / 1

Start Date: 2-1-1996

Red Bluff-Messer Drive Spatial Scale: NGH

40.1638, -122.2213 Samp. Method: SI

061030002 Mthd. Code/POC: 063 / 2

Start Date: 1-1-1998

Tuscan Butte Spatial Scale: REG

40.2622, -122.0928 Samp. Method: UV

061030004 Mthd. Code/POC: 087 / 1

Start Date: 6-1-1995

Table 4 (cont.)

Additional Information about the Monitors

_______________________________________________________________________

23 Annual Monitoring Network Report for Twenty-three Districts in California
(Monitors reporting data in 2013)

OZONE CO NO2 SO2 PM2.5* PM10*

Station/Geographical Coordinates/AQS Site # 44201 42101 42602 42401 88101 81102

Yolo County / CBSA: Sacramento-Arden-Arcade-Roseville Metropolitan Statistical Area

Davis-UCD Campus Spatial Scale: URB NGH

38.5352, -121.7730 Samp. Method: UV CL

061130004 Mthd. Code/POC: 087 / 1 099 / 1

Start Date: 9-1-1987 5-21-1996

West Sacramento-15th Street Spatial Scale: NGH

38.5713, -121.5258 Samp. Method: SI

061132001 Mthd. Code/POC: 063 / 1

Start Date: 9-1-1990

Woodland-Gibson Road Spatial Scale: URB NGH URB

38.6605, -121.7305 Samp. Method: UV SQ SI

061131003 Mthd. Code/POC: 087 / 1 118 / 1 063 / 1

Start Date: 5-27-1998 1-9-1999 10-26-1998

Notes:

This table only lists sites and monitors that have reported data in 2013. Lead monitors are not included 

in this list because there is no lead monitoring in the areas included in this report.

After a county name, the table lists the U.S. Office of Management and Budget's Core-Based Statistical 

Area (CBSA) that includes the county. The term CBSA includes both Metropolitan Statistical Areas and 

Micropolitan Statistical Areas. A Metropolitan Statistical Area has at least one urban area with a 

population of 50,000 or more. A Micropolitan Statistical Area has at least one urban area with a 

population of 10,000 to less than 50,000.

*Monitoring information inside a parenthesis ( ) in a PM column denotes that a continuous PM FEM 

monitor is located at the site. Monitoring information without a parenthesis reflects the filter-based PM 

FRM monitor.

**The filter-based PM10 FRM monitors at the Middletown, Glenbrook and Lakeport sites located in 

Lake County are reporting PM10 data in local conditions (i.e., 85101) and not in standard temperature 

and pressure (i.e., 81102). 

***In addition to the Redding-Health Department site (060890004), there are also the Redding-Toyon 

and Redding-Buckeye sites located in the City of Redding. The Redding-Toyon and Redding-Buckeye 

sites are non-regulatory sites.

_______________________________________________________________________

24 Annual Monitoring Network Report for Twenty-three Districts in California
Codes used in Table 4

MIC Microscale

MID Middle Scale

NGH Neighborhood Scale

URB Urban Scale

REG Regional Scale

CL Chemiluminescent

FL Fluoresecence

IR Nondispersive infrared

SCH Low volume single channel sampler, size selective inlet

SI High volume sampler, size selective inlet

SQ Low volume sequential sampler, size selective inlet

UV Ultraviolet absorption

XG X-ray fluorescence

BAM Beta Attenuation Monitor

TEOM Tapered Element Oscillating Microbalance Monitor

Method codes

047 Thermo Electron/Thermo Environmental Instr., Inc. Model 49, 49C, & 49i Ozone analyzer

063 Anderson-General Metal Works Model 1200 High Volume sampler

077 Advance Pollution Instruments Model 100 SO2 analyzer

087 Teledyne -Advance Pollution Instuments Model 400 or T400 Ozone analyzer

093 Advance Pollution Instruments Model 300, GFC CO analyzer

098 Rupprecht & Patashnick Partisol Model 2000 Air Sampler

099 Advance Pollution Instruments Model 200A NO analyzer

117 Rupprecht & Patashnick Model 2000 PM2.5 Air Sampler

118 Rupprecht & Patashnick Plus Model 2025PM SEQ PM2.5 Air sampler

122 Met One BAM/GBAM Model 1020 Monitor

141 Tisch EnvironmentalModel TE-6070 PM10 High-Volume Sampler

170 Met One BAM Model 1020 Monitor PM2.5 VSCC FEM

593 Advance Pollution Instruments Model 300 EU, GFC CO analyzer

731 Met One BAM-1020 Monitor W/PM2.5 SCC

 

 

 

Sampling methods

Spatial scales

 

Notes: POC stands for parameter occurrence code. This code is used to differentiate between 

the numbers of physical monitors at a site that measure for the same pollutant. For example, the 

PM10 monitors at a collocated PM10 site will use different POCs to differentiate between the 

primary and quality assurance PM10 monitors.

_______________________________________________________________________

25 Annual Monitoring Network Report for Twenty-three Districts in California
Information on the continuous PM2.5 non-FEM monitors included in this plan

The CFR requires that monitors are FRM, FEM or ARM and meet certain siting 

criteria in order for the data to be used for NAAQS comparisons. While all 

continuous PM10 monitors included in this report are FEM monitors, there are 

some continuous PM2.5 monitors that are non-FEMs. Table 5 lists the continuous 

PM2.5 non-FEM monitoring sites that are covered in the geographical scope of 

this report. The continuous PM2.5 data reported from these non-FEM monitors 

are excluded from NAAQS comparison. However, these non-FEM monitors are 

California Approved Samplers (CAS) and the data are used in AirNow for Air 

Quality Index reporting and are also used for State designations.

Table 5

Monitoring Sites Operating PM2.5 Non-FEM monitors

Site Name AQS Number

Chester-222 1st Avenue 060631007

Chico-East 060070008

Colfax-City Hall 060610004

Colusa-Sunrise Blvd 060111002

Davis-UCD Campus 061130004

Grass Valley-Litton Building 060570005

Gridley-Cowee Avenue 060074001

Lincoln-1st Street 060612002

Paradise-6701 Clark Road 060072002

Portola-420 N Gulling St 060631010

Quincy-N Church Street 060631006

Roseville-N Sunrise Blvd 060610006

Tahoe City 060611004

Truckee-Fire Station 060571001

Willows-E Laurel Street 060210003

Yosemite Village-Visitor Center 060431001

Yuba City-Almond Street 061010003

_______________________________________________________________________

26 Annual Monitoring Network Report for Twenty-three Districts in California
Section 5. Federal Minimum Monitoring Requirements

For most pollutants, U.S. EPA has established minimum monitoring requirements. 

These requirements are usually based on the CBSA along with considerations of 

population, emissions, or current air quality. Minimum monitoring requirements 

for ozone, PM2.5, PM10, PM-coarse, NO2, SO2, lead and chemical speciation will 

be discussed in this section. In contrast, there are also monitoring requirements 

that apply to an entire Primary Quality Assurance Organization (PQAO) or State 

or are based on ozone nonattainment classification, which will be discussed in 

the next section.

Federal Ozone, PM10, and PM2.5 Monitoring Requirements

Minimum monitoring requirements are specified in federal regulations (Appendix 

D of Title 40, Part 58 of the CFR). The requirements are based on the population 

of the CBSA and the severity of the air quality problem, as measured by the 

design value. Table 6 summarizes the required and existing ozone, PM2.5 and 

PM10 monitors for the nine CBSAs covered in this report. In all cases, sufficient 

monitoring exists and no additional monitoring is required.

To provide a broader picture of California, Figure 2 and Table 6a provide a 

complete list of the CBSAs in California, including those covered in other district 

network plans. Note that ozone and PM monitoring are only required in 

Metropolitan areas and not in Micropolitan areas (Refer to detailed information on 

CBSA, Metropolitan and Micropolitan areas on page 10 of this report). Additional 

information on the ozone, PM2.5, continuous PM2.5 and PM10 monitoring 

requirements and compliance with federal requirements can be found in 

Appendix B of this report.

Finally, for PM2.5, the CFR also requires near roadway monitoring in CBSAs with 

a population of one million or more. Several CBSAs covered by this network 

plan have a sufficiently high population to require a near roadway PM2.5 monitor. 

The required monitors will be placed in the portion of the CBSA covered by 

districts preparing their own plan. For further information, refer to the following 

district plans:

• South Coast AQMD (Los Angeles-Long Beach-Anaheim and Riverside-San 

Bernardino-Ontario CBSAs)

• Sacramento Metropolitan AQMD (Sacramento-Arden Arcade-Roseville CBSA)

_______________________________________________________________________

27 Annual Monitoring Network Report for Twenty-three Districts in California
Table 6

Numbers of Required and Existing Sites by Core Based Statistical Area (CBSA)

(CBSAs that include the twenty-three air districts included in this report)

Core Based 

Statistical Area 

(CBSA)

Pop.

Ozone PM2.5 PM10 

Required Existing Required Existing Required Existing Required Existing

sites sites sites sites Cont.1 Cont. sites sites

Bakersfield* 839,361 2 8 2 4 1 3 1-2 4

Chico 220,000 1 2 1 1 1 3 0 1

Los Angeles-Long 

Beach-Anaheim* 12,828,837 4 19 3 12 2 8 2-4 10

Redding 177,223 1 4 0 1 0 0 0 3

Riverside-San 

BernardinoOntario*

4,224,851 3 21 3 10 2 8 6-10 17

SacramentoArden ArcadeRoseville*

2,149,127 2 17 3 6 2 11 2-4 11

Santa Rosa* 483,878 1 2 0 1 0 1 0-1 3

Vallejo-Fairfield* 413,344 2 3 0 2 0 2 0-1 2

Yuba City 166,892 1 2 0 1 0 1 0 1

Notes:

2011-2013 air quality data was used in determining the number of required sites. In addition, the 

number of required sites includes both SLAMS and SPM monitors. This table excludes tribal 

monitoring sites. Population is based on year 2010 Census data. 

*Parts of these CBSAs are included in the geographical scope of this report, and parts are within 

the geographical scope of reports being completed by the districts. The numbers of sites listed 

are for the entire CBSA. Table 6a shows the completed list of CBSAs in California.

1

Continuous refers to a continuous PM2.5 monitor, i.e., one that measures hourly data. For this 

assessment, both continuous FEM and non-FEM PM2.5 monitors were counted for each CBSA.

_______________________________________________________________________

28 Annual Monitoring Network Report for Twenty-three Districts in California
Figure 2

Map showing the Core-Based Statistical Areas in California

Data Source: U.S. Census Bureau.

Note: The Los Angeles-Long Beach-Santa Ana CBSA was reclassified by OMB to the 

Los Angeles-Long Beach-Anaheim CBSA in February 2013.

_______________________________________________________________________

29 Annual Monitoring Network Report for Twenty-three Districts in California
Table 6a

Core-Based Statistical Areas in California (Metropolitan Areas)

CBSA Name County(ies) Included in the ARB 

plan?

Included in other District

plan?

Bakersfield Kern Yes, Eastern Kern San Joaquin Valley 

Chico Butte Yes --

El Centro Imperial No Imperial

Fresno Fresno No San Joaquin Valley 

Hanford-Corcoran Kings No San Joaquin Valley 

Los Angeles-Long BeachAnaheim

Los Angeles and Yes, Antelope Valley South Coast

Orange

Madera Madera No San Joaquin Valley 

Merced Merced No San Joaquin Valley 

Modesto Stanislaus No San Joaquin Valley 

Napa Napa No Bay Area

Oxnard-Thousand OaksVentura Ventura No Ventura County

Redding Shasta Yes --

Riverside-San BernardinoOntario

Riverside and

Yes, Mojave Desert South Coast

San Bernardino

Sacramento-RosevilleArden Arcade El Dorado, Placer, 

Sacramento, and 

Yolo

Yes, Placer County; 

Yolo-Solano Sacramento Metropolitan

Salinas Monterey No Monterey Bay Unified

San Diego-Carlsbad San Diego No San Diego County

San Francisco-OaklandHayward

Alameda, Contra 

Costa, Marin, San 

Francisco, and San 

Mateo

No Bay Area

San Jose-Sunnyvale-Santa 

Clara

Santa Benito and 

Santa Clara

No Bay Area

San Luis Obispo-Paso 

Robles-Arroyo Grande

San Luis Obispo No San Luis Obispo County

Santa Cruz-Watsonville Santa Cruz No Monterey Bay Unified

Santa Maria-Santa 

Barbara Santa Barbara No Santa Barbara County

Santa Rosa Sonoma Yes, Northern Sonoma Bay Area

Stockton-Lodi San Joaquin No San Joaquin Valley 

Vallejo-Fairfield Solano Yes, Yolo-Solano Bay Area

Visalia-Porterville Tulare No San Joaquin Valley 

Yuba City Sutter and Yuba Yes --

_______________________________________________________________________

30 Annual Monitoring Network Report for Twenty-three Districts in California
Table 6a (cont.)

Core-Based Statistical Areas in California (Micropolitan Areas)

CBSA Name County(ies) Included in the 

ARB plan?

Included in other District

plan?

Bishop Inyo No Great Basin Unified

Clearlake Lake Yes --

Crescent City Del Norte No North Coast Unified

Eureka-Arcata-Fortuna Humboldt No North Coast Unified

Phoenix Lake-Cedar Ridge Tuolumne Yes --

Red Bluff Tehama Yes --

Susanville Lassen Yes --

Truckee-Grass Valley Nevada Yes --

Ukiah Mendocino Yes --

Federal Near-Road, Area-Wide and Susceptible Population NO2 Monitoring 

Requirements

There are new federal requirements for NO2 near roadway monitors that are 

applicable in California. However, none of the 23 districts covered in this report 

are required to deploy near roadway monitors. Near roadway monitors required 

for the Sacramento-Arden-Arcade-Roseville CBSA are being addressed by the 

Sacramento Metropolitan District. Near roadway monitors required for the 

Riverside-San Bernardino-Ontario and Los Angeles-Long Beach-Anaheim

CBSAs are being addressed by the South Coast District. Near roadway monitors 

required for the San Diego-Carlsbad-San Marcos CBSA are being addressed by 

the San Diego County District. Near roadway monitors required for the OxnardThousand Oaks-Ventura CBSA are being addressed by the Ventura County 

District. Near roadway monitors required for the San Francisco-OaklandFremont and San Jose-Sunnyvale-Santa Clara CBSAs are being addressed by 

the Bay Area District, and near roadway monitors required in the Bakersfield, 

Fresno, Modesto, and Stockton CBSAs are being addressed by the San Joaquin 

Valley District. All six of these districts are preparing separate network plans 

and/or separate documents related to the implementation of the NO2 near 

roadway requirements. Table 7 lists the districts responsible for planning and 

implementing near-road NO2 monitoring in California.

In addition, federal monitoring regulations also require that there must be NO2

monitoring at a location of expected highest NO2 concentration representing the 

neighborhood or larger spatial scales within each CBSA with a population of 

1,000,000 or greater. There are six CBSAs that meet the population criteria: Los 

Angeles-Long Beach-Anaheim, Riverside-San Bernardino-Ontario, San DiegoCarlsbad-San Marcos, San Francisco-Oakland-Fremont, San Jose-SunnyvaleSanta Clara and Sacramento-Roseville-Arden Arcade. Area-wide NO2

monitoring in the Los Angeles-Long Beach-Anaheim and Riverside-San 

_______________________________________________________________________

31 Annual Monitoring Network Report for Twenty-three Districts in California
Bernardino-Ontario CBSAs is being addressed by the South Coast District. 

Area-wide NO2 monitoring in the San Diego-Carlsbad-San Marcos CBSA is being 

addressed by the San Diego County District. Area-wide NO2 monitoring in the 

San Francisco-Oakland-Fremont and San Jose-Sunnyvale-Santa Clara CBSAs 

is being addressed by the Bay Area District. Area-wide NO2 monitoring in the 

Sacramento-Roseville-Arden Arcade CBSA is being addressed by the 

Sacramento Metropolitan District. There is no required NO2 area-wide 

monitoring for the CBSAs included in this network plan.

Table 7

Near-Road NO2 Monitoring Requirements in California

CBSA

District 

Responsible 

for NO2 NearRoad 

Monitoring

Number of 

Required NO2

Monitors

Bakersfield San Joaquin 

Valley 1

Fresno San Joaquin 

Valley 1

Los Angeles-Long 

Beach-Anaheim South Coast 2

Modesto San Joaquin 

Valley 1

Oxnard-Thousand 

Oaks-Ventura

Ventura 

County 1

Riverside-San 

BernardinoOntarioSouth Coast 2

SacramentoArden-ArcadeRoseville

Sacramento 

Metro 1

San DiegoCarlsbad-San 

Marcos

San Diego 2

San FranciscoOakland-Fremont Bay Area 2

San JoseSunnyvale-Santa 

Clara

Bay Area 1

Stockton San Joaquin 

Valley 1

Finally, federal regulations also require that NO2 monitoring is conducted in 40 

locations throughout the United States in selected areas to protect susceptible 

_______________________________________________________________________

32 Annual Monitoring Network Report for Twenty-three Districts in California
and vulnerable populations. The locations of these areas are determined by 

each U.S. EPA Regional Administrator. In California, seven locations were 

selected to be part of the nationwide network, which includes San Diego, 

Oakland, Long Beach, Los Angeles, San Bernardino, Parlier, and Bakersfield. 

The selected monitoring locations are located in regions covered by the San 

Diego, Bay Area and San Joaquin Valley District network plans.

Federal CO and SO2 Monitoring Requirements

Monitoring for carbon monoxide (CO) is only required at a select number of 

near-road monitoring sites, beginning in the year 2015 (and continuing through 

2017) and will be addressed in future network plans by the implementing 

agencies. Regardless of the future implementation of the near-roadway CO 

requirements, California has and continues to monitor for CO on a regional basis.

On June 2, 2010, the U.S. EPA published the final rule for the revised federal 

SO2 standard which specifies the minimum number of sites at which state and 

local air agencies must deploy SO2 monitors. The monitoring regulations require 

SO2 monitors be placed in CBSAs based on a population weighted emissions 

index (PWEI) for the area. The PWEI of a CBSA is calculated by multiplying the 

latest available SO2 emission data within each CBSA by the population of the 

CBSA and then divided by one million. The final rule requires:

• Three SO2 monitors in CBSAs with PWEI values of one million or more;

• Two SO2 monitors in CBSAs with PWEI values less than one million but 

greater than 100,000; and

• One SO2 monitor in CBSAs with PWEI values greater than 5,000 but less 

than 100,000.

California has thirty-five CBSAs with population ranging from 17,000 to more 

than 12 million people. Table 8 lists the CBSAs in California that require SO2

monitoring. In addition, Table 8 shows that these CBSAs exceed federal 

monitoring requirements for SO2. None of the areas included in this report are 

required to monitor for SO2.

_______________________________________________________________________

33 Annual Monitoring Network Report for Twenty-three Districts in California
Table 8

Minimum Monitoring Requirements for SO2

CBSA County(ies) Population 

(2010)

SO2 

emission 

per CBSA 

(tpy)

PWEI 

(Million 

personstpy)

Number 

of 

Required 

Monitors

Number 

of Active 

Monitors

Number of 

Additional 

Monitors 

Needed

Los AngelesLong BeachSanta Ana

Los Angeles 

and Orange 12,828,837 13,498 173,785 2 5 0

Riverside-San 

BernardinoOntario

Riverside and 

San 

Bernardino

4,224,851 2,478 10,266 1 4 0

San 

FranciscoOaklandFremont

Alameda, 

Contra Costa, 

San 

Francisco, 

San Mateo, 

and Marin

4,317,853 12,669 54,702 1 9 0

Federal Lead Monitoring Requirements

On December 14, 2010, U.S. EPA finalized the rule for the revised federal lead 

(Pb) standard, which also specifies the monitoring requirements for Pb. While 

the final rule maintains the airport monitoring threshold at 1.0 ton per year (tpy), 

the rule lowers the industrial source-oriented monitoring threshold from 1.0 tpy to 

0.5 tpy. In addition, the final rule replaces the population-based monitoring 

requirement with a requirement to monitor for Pb at urban NCore sites.

The U.S. EPA selected 15 airports for a one-year study as part of the new Pb 

rule. Five airports are in California: Palo Alto Airport, McClellan-Palomar Airport, 

Reid-Hillview Airport, Gillespie Field Airport, and San Carlos Airport. None of 

these airports fall within the geographical scope of this report. With respect to 

source-oriented monitoring for Pb, the only stationary sources in California 

subject to the 0.5 tpy threshold are located in the South Coast Air Basin. The 

South Coast annual network plan provides a description of their source-oriented 

lead monitors. The areas covered in this network plan are not required to 

conduct source-oriented lead monitoring.

Lastly, the final rule requires Pb monitoring at urban NCore sites. Urban NCore 

sites are those sites in a CBSA of 500,000 or more. Currently, there are six urban 

NCore sites in California, located in El Cajon, Fresno, Los Angeles, Riverside, 

Sacramento and San Jose. A seventh rural NCore site is located at White 

Mountain Research Station. None of these NCore sites are located in areas 

covered by this network plan. More information on NCore sites is provided in 

Section 6 of this report.

_______________________________________________________________________

34 Annual Monitoring Network Report for Twenty-three Districts in California
Federal PM-Coarse (PM10-2.5) Monitoring Requirements

The CFR requirement for coarse particulate matter monitoring is in Section 4.8, 

Appendix D of 40 CFR 58. PM-coarse monitoring is required at NCore sites. At

the time this report was drafted, the six urban NCore sites currently monitored for 

PM-coarse.

Federal PM2.5 Chemical Speciation Trends Network (STN) Requirements

The requirements for PM2.5 trends speciation monitoring is in Section 4.7.4, 

Appendix D of 40 CFR 58. Each state is required to conduct chemical speciation 

monitoring at sites designated to be part of the federal Speciation Trends 

Network (STN). At the time this report was drafted, and according to AQS, there 

are seven STN sites in California, which include Fresno-Garland, BakersfieldCalifornia Street, Rubidoux-Mission Blvd., Sacramento-Del Paso Manor, El 

Cajon, San Jose-Jackson Street and Simi Valley. Each STN site monitored more 

than 30 chemical speciation measurements. However, not all sites collect the 

same speciated compounds. None of these STN sites are located in areas 

covered by this network plan.

_______________________________________________________________________

35 Annual Monitoring Network Report for Twenty-three Districts in California
Section 6. Federal Monitoring Requirements at State-level or by PQAO or

 Area

Certain parts of 40 CFR 58 require that state and local agencies operate 

multi-pollutant monitoring sites, meet PM collocation requirements, as well as 

monitor at sites that are considered background, transport, or highest (maximum) 

concentration sites. The rest of this Section discusses these requirements.

Federal NCore Monitoring Requirements for California

On October 17, 2006, U.S. EPA issued amendments to the ambient air 

monitoring requirements for criteria pollutants. These amendments are codified 

in 40 CFR Parts 53 and 58. One of the most significant changes in the 

regulations was the requirement to establish a network of National Core (NCore) 

multi-pollutant monitoring stations. NCore sites include neighborhood and urban 

scale measurements in metropolitan areas and rural areas. Sites are long term 

and sited away from direct emission sources that could impact the ability to 

detect area-wide concentrations. These stations provide data on several 

pollutants at lower detection limits and replace the National Air Monitoring Station 

(NAMS) network that had existed for many years. 

Currently, in California, there are a total of seven monitoring sites that are part of 

the national NCore network. The seven NCore sites are listed in Table 9 along 

with the agency that operates the site. Note that in February 2014, the San 

Diego Air Pollution Control District temporary relocated the El Cajon site to a new 

location approximately 3.8 kilometers from its current location. This move is 

expected to last between 12-18 months due to construction on the school ground 

near the monitoring station. More information regarding the temporary relocation 

can be found in the 2014 San Diego network plan.

Table 9

NCore Monitoring in California

NCore Site Name NCore Type

Agency 

Responsible for 

NCore 

Monitoring

El Cajon Urban San Diego

Fresno-Garland Urban ARB

Los Angeles-North 

Main Urban South Coast

Riverside-Rubidoux Urban South Coast

Sacramento-Del 

Paso Manor Urban Sacramento Metro

San Jose Urban Bay Area

White Mountain 

Research Station Rural Great Basin 

Unified

_______________________________________________________________________

36 Annual Monitoring Network Report for Twenty-three Districts in California
6.1 Federal Collocation Requirements for the ARB PQAO

Appendix A of 40 CFR 58 includes requirements for collocation of samplers as 

part of quality checks for the PM2.5, continuous PM2.5, PM10, and lead (Pb) 

monitoring networks. The CFR contains separate collocation requirements for 

these monitors. The requirements are to be met for each primary quality 

assurance organization (PQAO). Four PQAOs exist in California, one each for 

the San Francisco Bay Area AQMD, San Diego County APCD, and South Coast 

AQMD, and one for the remainder of the State that is called the ARB PQAO.

PM2.5 Collocation Status

For PM2.5, the CFR requires that for each type of manual PM2.5 monitor, 15 

percent of the sites within a PQAO have a collocated monitor of the same type. 

Two types of manual PM2.5 FRMs exist currently in the ARB PQAO. Collocation 

requirements apply to each method type. The types of manual PM2.5 samplers 

are the R&P Non-sequential (117) and R&P Sequential (118). At the time this 

report was drafted, one collocation site is required for method 117 and three 

collocation sites are required for method 118. 

For method 117, the collocation site is Victorville. This site is operated by the 

Mojave Desert Air Quality Management District (MDAQMD). By the end of 2014, 

MDAQMD is proposing to switch out one of the manual FRM monitors at the 

Victorville site to a continuous PM2.5 FEM monitor. Once this proposal becomes

fully implemented, the ARB PQAO will have to find a replacement site to 

collocate for this method type. ARB will reassess the collocation situation for this 

method type and coordinate with districts within the ARB PQAO to ensure that 

this collocation requirement continues to be met. 

For method 118, the collocation sites are: Bakersfield-California, Fresno-Garland, 

Sacramento-Del Paso Manor and Truckee. When this report was drafted, there 

was only one proposed change to these four collocation sites. The Northern 

Sierra Air Quality Management District (NSAQMD) proposed to relocate the 

collocated PM2.5 monitor from the Truckee site to the Portola site. The NSAQMD

is currently requesting U.S. EPA approval for the relocation. Additional 

information regarding these proposals will be provided in the 2015 ARB network

plan.

In the ARB PQAO, Calexico-Ethel is the only site that operates two PM2.5

monitors that are of different method type. At this site, one monitor is a manual 

FRM (R&P-method 118) and the other monitor is a manual FEM (Thermo 

Scientific-method 145). The FRM (method 118) is the primary monitor and the 

FEM (method 145) is the collocated monitor. Due to the different method type of 

the PM2.5 monitors, ARB is waiting for further clarification from U.S. EPA on 

whether this type of monitoring setup could be used as an additional collocation 

monitoring site. Table 10 summarizes the manual PM2.5 collocation requirements 

in the ARB PQAO as well as the collocation sites by method type.

_______________________________________________________________________

37 Annual Monitoring Network Report for Twenty-three Districts in California
Table 10

Collocation Requirements for Manual PM2.5 Monitors

Method Code

Number of 

Primary 

Monitors

Number of 

Required 

Collocated 

Monitors

Number of 

Active 

Collocated 

Monitors

117 8 1 1

118* 22 3 4 (or 5)

Notes:

Method 117 FRM (R&P non-seq.): Victorville

Method 118 FRM (R&P seq.): Bakersfield, Fresno, Sacramento and Truckee

*The Calexico-Ethel site has two filter PM2.5 monitors of which have different methods. The 

primary PM2.5 monitor at this site is an R&P sequential monitor (method 118) and the quality 

assurance monitor is a Thermo (method 145). Regardless of whether this monitoring setup could 

be used for collocation purposes, the ARB PQAO met collocation requirements for method 118.

The CFR also requires that for each continuous PM2.5 federal equivalent method 

(FEM), 15 percent of the sites must be collocated, but that the first collocation 

monitor is an FRM, the second an FEM, and so on alternating FRM with FEM as 

additional collocation monitors are required. At the time this report was drafted, 

34 sites in the ARB PQAO operate continuous PM2.5 FEM monitors representing 

three method types. The three methods are the Met-One BAM (170), Thermo 

Scientific TEOM (181) and Grimm (195) with 32 sites in the ARB PQAO operating 

method 170, and one site each operating method 181 and 195. 

For method 170, the 32 sites in the ARB PQAO require that five sites are 

collocated of which the first, third, and fifth collocations are between an 

FEM/FRM and the second and fourth collocations are between an FEM/FEM. At 

the time this report was drafted, there are two FEM/FRM sites in the ARB PQAO: 

Modesto and Salinas. To meet this FEM/FRM requirement, one additional 

FEM/FRM collocation site is needed in the ARB PQAO. ARB is proposing to add 

a PM2.5 FRM monitor to the Madera site to collocate with the existing continuous 

PM2.5 FEM monitor. Once this proposed plan becomes implemented at the 

Madera site, the ARB PQAO would meet the FEM/FRM collocation requirement. 

In regards to the FEM/FEM collocation requirement, there are currently two 

FEM/FEM sites in the ARB PQAO: Stockton-Hazelton and Simi Valley. The 

Stockton-Hazelton site was the existing FEM/FEM site and the Simi Valley site 

recently became an FEM/FEM site in March of 2014. The ARB PQAO will not 

require an additional FEM/FEM site in the PQAO until the continuous PM2.5 

network which utilizes method 170 reaches 37 sites.

For method 181, the one site utilizing this method in the ARB PQAO is the Keeler 

site located in Inyo County. The Great Basin Unified District discontinued one of 

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38 Annual Monitoring Network Report for Twenty-three Districts in California
the two PM2.5 FRM monitors at the Keeler in July 2013 and re-designated the 

continuous PM2.5 FEM monitor as the primary monitor at this site. The Keeler 

site currently meets collocation requirements.

For method 195, the one site utilizing this method in the ARB PQAO is the 

Humboldt Hill site located in the City of Eureka. The North Coast Unified District

discontinued the PM2.5 FRM at the Eureka-I Street site and added it to the 

Humboldt Hill site, collocating with the FEM Grimm monitor (195). The Humboldt 

Hill site currently meets collocation requirements. However, the District is 

planning to designate the PM2.5 FRM monitor at Humboldt Hill as the primary 

monitor and re-designate the Grimm monitor as the quality assurance monitor at 

this site. In addition, the District is planning on asking U.S. EPA approval via a 

waiver to exclude the Grimm data at this site from NAAQS comparison. ARB is 

waiting for the District’s plan in writing and U.S. EPA’s responses to the plan. 

More detailed information regarding this proposed network change will be 

provided in the 2015 ARB network plan. Table 11 summarizes the collocation 

requirements for continuous PM2.5 FEM in the ARB PQAO.

Table 11

Collocation Requirements for continuous PM2.5 FEM

Method 

Code

Number of 

Primary 

Monitors

Number of 

Required 

Collocated 

Monitors

Number of 

Active 

Collocated 

FRM Monitors

Number of Active 

Collocated FEM 

Monitors (same 

method designation 

as primary)

170* 32 5 2 (need 1) 2

181 1 1 1 0

195 1 1 1 0

Notes:

FEM/FRM sites: Humboldt Hill, Modesto, Keeler and Salinas

FEM/FEM site: Stockton and Simi Valley

*The ARB proposed to add a PM2.5 FRM monitor to the Madera site. Once this proposal

becomes implemented, the ARB PQAO meets collocation requirements for continuous PM2.5

FEM.

The CFR also requires that 80 percent of the collocated PM2.5 monitors are sited 

at monitoring stations that are within +/- 20 percent of the federal PM2.5 

standards. California is a very large state in which environmental conditions 

(e.g., temperature, precipitation, humidity, wind speeds, and elevation) vary 

widely and the composition of the PM2.5 varies significantly. Also, a large number 

of operating agencies operate sites in the statewide PM2.5 network. ARB and 

local air districts designed the locations of collocated PM2.5 samplers to strike a 

balance in adequately representing all of these factors. In this way, the quality 

control function of the collocated monitoring is best realized. While Appendix A of 

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39 Annual Monitoring Network Report for Twenty-three Districts in California
40 CFR 58 requires 80 percent of the collocated monitors to be within + 20 

percent of the applicable federal air quality standard, focusing on achieving this 

was deemed to result in too much clustering of the collocated monitors in too few 

of the factors needing representation. To support this determination, the 

U.S. EPA requested that the network plan includes design values of the 

collocation sites. Table 12 lists the design values of the PM2.5 FRM and FEM 

monitors at each of the collocation sites in the ARB PQAO. Note that exceptional 

events are included in the determination of the design values for these PM sites.

Table 12

Design Values for PM2.5 Collocation Sites (ug/m3)

Collocation Site Name 2013 Annual 

Design Value

2013 24-hr 

Design Value

Bakersfield (FRM/FRM) 16.4 65

Calexico (FRM/FRM) 13.8 30

Fresno (FRM/FRM)* 15.5 62

Sacramento (FRM/FRM) 10.4 36

Truckee (FRM/FRM) 7 21

Victorville (FRM/FRM) 6.8 13

Collocation Site Name 2013 Annual 

Design Value

2013 24-hr 

Design Value

Humboldt Hill (FEM/FRM)** -- --

Keeler (FEM/FRM) 7.6 38

Modesto (FEM/FRM) 13.6 51

Salinas (FEM/FRM) 6.3 14

Simi Valley (FEM/FEM) 9.1 20

Stockton (FEM/FEM) 13.9 45

Notes:

*The 2013 design values for the Fresno site were computed with data from the Fresno-1st Street 

site and Fresno-Garland site.

**There were insufficient data to compute valid 2013 design values for the Humboldt Hill site.

PM10 Collocation Status

The CFR also requires that 15 percent of PM10 sites with manual monitoring have 

collocated samplers. For this assessment, per U.S. EPA’s guidance, the ARB 

combines all of the PM10 FRM monitors regardless of its method type to get the 

total number of required collocation sites in the ARB PQAO. Currently, there are 

49 PM10 FRM sites in the ARB PQAO of which four sites are already collocated. 

The collocation sites are: Bakersfield-California, Fresno-Drummond, 

Sacramento-Del Paso Manor and Keeler.

To meet the PM10 collocation requirement, the ARB PQAO needs three additional 

PM10 collocation sites because the Simi Valley site is no longer collocated for 

_______________________________________________________________________

40 Annual Monitoring Network Report for Twenty-three Districts in California
PM10 FRM. The Simi Valley site currently has only a continuous PM10 FEM 

monitor. ARB is currently evaluating site locations in the ARB PQAO to add three 

additional PM10 collocation sites. More information regarding the selection of 

additional PM10 collocation sites will be provided in the 2015 ARB network plan.

Lead Collocation Status

On December 14, 2010, U.S. EPA finalized the rule for the revised federal lead 

(Pb) standard, which also specifies the collocation requirements for Pb. The 

regulations specify that PQAOs that have a combination of source and 

non-source Pb sites have 15 percent of their Pb monitoring sites collocated. The 

regulations also require that the Pb network be treated independently from the 

PM network, and that the first collocation site be at the highest Pb concentration 

site within the network. Moreover, the regulations specify that if a PQAO has no 

source or non-source Pb monitoring, and the only Pb monitoring is conducted at 

NCore sites, then the collocated Pb monitor must be of the same method 

designation as the primary Pb monitor. 

The ARB PQAO requires no source or non-source Pb monitoring. However, the 

ARB PQAO does have two NCore sites located at Fresno-Garland and 

Sacramento-Del Paso Manor and one SLAMS site located at Calexico-Ethel that 

monitors for Pb. Pb collocation at the NCore sites is being handled at the 

national level so ARB is not required to collocate for Pb at either the Fresno or 

Sacramento sites. However, ARB is required to collocate for Pb at the

Calexico-Ethel site. Since Pb monitoring at Calexico-Ethel is not required, ARB 

could discontinue Pb monitoring at this site if ARB chooses too. However, if ARB 

decides to continue Pb monitoring at Calexico-Ethel, then ARB will need to 

collocate. ARB is currently evaluating options and will ensure that collocation for 

Pb is met for the PQAO by the 2015 network plan.

Distance between Collocated PM Monitors

The CFR requires that information regarding the distance between collocated PM 

monitors be included in the network plan. Table 13 lists the distance between the 

collocated monitors at each of the PM collocation sites in the ARB PQAO. Note 

that most of the PM collocation sites listed in Table 13 are not covered in the 

geographical scope of this network plan. However, because collocation is a 

PQAO requirement, ARB is including this information in this plan.

_______________________________________________________________________

41 Annual Monitoring Network Report for Twenty-three Districts in California
Table 13

Distance between Collocated PM Monitors

PM2.5 FRM/FRM

Collocation Site 

Name

Distance 

(in meters)

Bakersfield 2.3

Calexico 2.0

Fresno 2.0

Sacramento 1.8

Truckee 4.6

Victorville 1.7

PM2.5 FEM/FRM

Collocation Site 

Name

Distance 

(in meters)

Humboldt Hill 2.0

Keeler 1.4

Modesto 2.8

Salinas 2.9

PM2.5 FEM/FEM

Collocation Site 

Name

Distance 

(in meters)

Simi Valley 2.1

Stockton 1.1

PM10 FRM/FRM

Collocation Site 

Name

Distance 

(in meters)

Bakersfield 2.3

Fresno 4.9

Keeler 1.7

Sacramento 2.8

Federal Background, Transport, Max Concentration and Area-wide PM2.5

Monitoring Requirements

Federal monitoring also required that the network plan list sites in California that 

represent background, transport, maximum concentration or area-wide 

monitoring for PM2.5. From a statewide perspective, background sites are 

intended to quantify regionally representative PM2.5 concentrations for sites 

located away from populated areas and other significant emission sources. The 

following sites serve as regional background sites in California:

Northern California background site - Point Reyes National Seashore

(AQS # 060410002)

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42 Annual Monitoring Network Report for Twenty-three Districts in California
Southern California background site – San Rafael Wilderness

(AQS # 060839000)

These background PM2.5 sites are a part of the Interagency Monitoring of 

Protected Visual Environments (IMPROVE) program, which is governed by a 

steering committee composed of representatives from federal and regional-state 

agencies. PM2.5 mass data (i.e., 88502) are currently being reported from these 

two sites into AQS. Note that ARB also operates a PM2.5 site at Point Reyes

(060410003) but this site is not the same site as the Point Reyes National 

Seashore site (060410002) operated by the National Park Service. ARB’s Point 

Reyes site was discontinued in December 2013. More information on the 

IMPROVE program can be found at:

http://vista.cira.colostate.edu/improve/Overview/Overview.htm

For transport monitoring, ARB has identified two PM2.5 monitoring sites within the 

geographical area of this report as transport sites. They are the Vallejo and 

Roseville sites, which capture pollutant transport from the Bay Area to the 

Sacramento region and pollutant transport from Sacramento to the outlying areas 

of Sacramento, respectively. Among the remaining sites included in this report,

ARB has identified a total of 19 area-wide PM2.5 monitoring sites. These sites 

are identified as area-wide based on their siting scale designation as either 

neighborhood, urban, or regional per Subpart A of 40 CFR, Part 58, Section 58.1. 

A subset of seven of the area-wide monitoring sites has been identified as

representing the maximum concentration site in each respective MSA. The areawide and maximum concentration PM2.5 sites are listed below. Note that not all 

PM2.5 sites are designated as background, transport, maximum concentration or 

area-wide. There are other purposes for PM2.5 monitoring; for example, 

monitoring for quality assurance purposes.

Area-wide PM2.5 Sites: 

Auburn Chico Colusa

Grass Valley Lakeport Lancaster

Mojave Portola Quincy

Red Bluff Redding Ridgecrest

Roseville San Andreas Ukiah

Willits Woodland Yreka

Yuba City

Maximum Concentration PM2.5 Sites:

Chico Lakeport Lancaster

Red Bluff Redding Willits

Yuba City

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43 Annual Monitoring Network Report for Twenty-three Districts in California
Section 7. Federal Air Quality Assurance

The information below, along with the information available via the web link 

(http://www.arb.ca.gov/aaqm/qa/qa.htm), provides an overview of ARB’s Quality 

Management Branch (QMB) compliance status with the requirements of 40 CFR 

Part 58, Appendices A, C, and E. The compliance status overview is part of the 

annual network plan requirement.

Background

The Quality Assurance Section (QAS) and Quality Management Section (QMS) 

fulfill the QMB mission to ensure ambient air quality data meet or exceed the 

quality and program objectives of the end users. QAS and QMS perform various 

quality assurance activities to verify that data collected comply with procedures 

and regulations set forth by U.S. EPA and can be considered good quality data 

and data-for-record. 

The quality assurance activities are achieved through various audits which are 

independent from the ambient air monitoring program responsibilities. 

California’s large network and unique ambient air monitoring challenges require a 

comprehensive state of the art audit program. ARB’s audit program meets the 

federal requirements for conducting annual performance evaluations and has 

been designated as equivalent to the National Performance Audit Program. 

Audits are conducted by using independent National Institute of Standards and 

Technology (NIST) traceable standards and must adhere to federally established 

acceptance criteria. 

QAS is responsible for conducting performance audits of criteria and non-criteria 

pollutant analyzers, particulate samplers, meteorological equipment, and 

laboratory analyses utilized for generating ambient level measurements. QAS 

also performs site reviews as well as reports quality assessment and quality 

control results. QMS is responsible for ensuring that ARB meets its federally 

mandated PQAO responsibilities. QMS performs system audits and provides 

quality assurance oversight of the PQAO districts.

During an audit, if a parameter fails to meet critical criteria (QA Handbook 

Volume II, Appendix D), an Air Quality Data Action (AQDA) request is issued to 

the facility operator. All AQDA’s must be investigated by the operator and 

resolved to bring the parameter in question into compliance. The station operator 

completes the AQDA by documenting the resolution, specifying the time period 

during which data was potentially affected, and recommending whether the data 

is to be released, corrected, or invalidated. QMB reviews the completed AQDA 

and discusses any concerns with the operator. A finalized copy of the AQDA is 

forwarded to the operator and ARB’s Air Quality Analysis Section. Other issues 

identified as systematic or operational criteria that may impact or potentially 

impact data quality is documented through the issuance of a Corrective Action 

Notification (CAN).

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44 Annual Monitoring Network Report for Twenty-three Districts in California
ARB Quality Assurance Activities

Monitoring Station Audits

Annually, QAS conducts through-the-probe (TTP) audits for all continuous 

gaseous analyzers in the network. TTP audits of the gaseous analyzers, 

monitoring for carbon monoxide, nitrogen dioxide, hydrogen sulfide, sulfur 

dioxide, and ozone are conducted in accordance with U.S. EPA requirements 

(Title 40, CFR, Part 58, Appendix A). These audits verify the accuracy of the 

gaseous analyzers and ensure the integrity of the entire sampling system. For 

most TTP audits, an audit van is transported by QAS to the ambient air 

monitoring station. Audit vans house the necessary instrumentation and 

equipment to allow the audit to be conducted at the same condition as the station 

instruments. TTP audits, depicted in Figure 2, are conducted by introducing 

NIST traceable gases from the van into the station sampling probe inlet at 

various concentrations. QAS compares the results obtained from the station 

analyzer to the known values generated in the van. 

Figure 3

Through-the-Probe Audit

TTP audit methodology can identify deficiencies caused by poor analyzer 

response, pollutant scavenging contaminants, and sampling system leaks. 

Deficiencies like these can cause the gaseous analyzers to fail an audit and 

possibly affect the quality of the ambient air data. 

Biannually, QAS determines the accuracy of each particulate sampler in the 

network by comparison of the instrument's flow rate to either a certified orifice or 

_______________________________________________________________________

45 Annual Monitoring Network Report for Twenty-three Districts in California
a mass flow meter. These devices are certified against a NIST traceable flow 

device or calibrator. The audit device is connected in-line with the sampler's flow 

path and the flow rate is measured while the sampler is operating under normal 

sampling conditions. The true flow is calculated from the audit device's 

calibration curve. The sampler's flow is then compared to the true flow, and a 

percent difference is determined for verifying compliance.

QAS also conducts annual sensor audits of meteorological parameters, using 

NIST traceable equipment. Accurate meteorological data are important for 

characterizing meteorological processes such as transport and diffusion, and to 

make air quality forecasts and burn-day decisions.

An integral part of a performance audit is conducting a siting evaluation. Stations 

that meet siting criteria at the time of initial setup may no longer conform due to 

updated regulations, or changes in surrounding conditions and land use. 

Physical measurements and observations are noted on the site survey or 

accompanying documentation to determine compliance with 40 CFR Part 58, 

Appendix E requirements. Many of the siting issues result from the growth of 

vegetation/trees infringing on the minimum distance required from probes/inlets.

Laboratory Performance and System Audits

Additionally, laboratory mass analysis performance audits are conducted 

annually by QAS. These audits utilize NIST certified weights, hygrometers, and 

temperature sensors to verify the accuracy of the laboratory balance, relative 

humidity, and temperature sensors. 

QMB conducts system audits to determine whether a district’s air monitoring 

program satisfies the requirements of 40 CFR Part 58 and U.S. EPA's Quality 

Assurance Handbook for Air Pollution Measurement Systems, Volume II. 

Compliance with these regulations is necessary if the data are to be considered 

data-for-record per the California Code of Regulations (Title 17, Article 3, Section 

70301). Data meeting these requirements are eligible to be used in actions taken 

pursuant to the federal and California Clean Air Acts.

Quality Assessment and Quality Control

QAS also ensures the quality of the data collected by the air monitoring stations 

operating in California through analysis of precision data submitted to U.S. EPA’s

AQS database. Precision checks for gaseous/continuous samplers are required 

once every two weeks. These precision checks are conducted nightly at ARB 

and some district operated sites, and weekly or bi-weekly at other district sites. 

Precision checks for non-continuous, collocated particulate samplers are to be 

performed at least every twelfth day. QAS staff analyzes the precision data in 

accordance with 40 CFR 58, Appendix A.

_______________________________________________________________________

46 Annual Monitoring Network Report for Twenty-three Districts in California
Air monitoring staff performs a one-point flow rate verification check at least once 

every month on the filter-based and automated PM analyzers. Air monitoring 

staff reviews these data and takes corrective action when the results exceed

U.S. EPA’s requirements. These flow rate verifications are used to assess bias of 

the automated instruments in accordance with 40 CFR Part 58, Appendix A, 

3.2.3. These bias estimates are further verified by the semi-annual flow rate 

audits that are conducted five to seven months apart in each calendar year. In 

the course of auditing the PM2.5 FRM and continuous samplers, the date of the 

last six months of flow rate and leak checks performed by the air monitoring staff 

are recorded. 

Audit Report Summary

Information about each air monitoring station audited by QMB is available at: 

http://www.arb.ca.gov/qaweb/sitelist_create.php. This web page provides the 

map location, latitude and longitude coordinates, site photos, the pollutants 

monitored, along with a detailed site survey of the instrumentation and physical 

parameters for each site.

The 2013 calendar year audit dates for both the gaseous analyzers and PM 

monitors operating at the monitoring sites covered in this report are provided in 

Table 14. The residence time for each gas analyzer is included in Table 15. 

Audit results are directly submitted to AQS quarterly per Appendix A of 40 CFR 

Part 58. In addition, as required by 40 CFR Part 58.15, ARB submits a data 

certification letter along with the required AQS reports (AMP450NC and AMP600) 

to U.S.EPA, annually. The last certification letter was sent to the U.S. EPA on 

May 16, 2014. In 2015, ARB intends to certify the data on or before the May 1 

deadline.

Table 14

2013 Audit Date Information for the Monitors in this Plan

Site Name Gaseous Audit First Flow Audit Second Flow Audit

Middletown-Anderson Springs 08/28/2013 02/28/2013 08/28/2013

Anderson-North Street 04/10/2013 04/10/2013 10/01/2013

Auburn – Atwood Road 08/13/2013 02/07/2013 08/13/2013

Auburn – Dewitt C Avenue - 02/07/2013 08/13/2013

Barstow 02/13/2013 02/13/2013 08/07/2013

Blythe-Murphy Street 02/12/2013 - -

Canebrake - 02/07/2013 08/27/2013

Chester - 03/13/2013 09/03/2013

Chico – East Avenue 07/09/2013 01/29/2013 07/09/2013

Cloverdale - 06/07/2013 12/10/2013

Colfax-City Hall 08/12/2013 02/07/2013 08/12/2013

Colusa-Sunrise Blvd 06/14/2013 06/14/2013 11/26/2013

_______________________________________________________________________

47 Annual Monitoring Network Report for Twenty-three Districts in California
Site Name Gaseous Audit First Flow Audit Second Flow Audit

Cool (seasonal) 08/12/2013 - -

Davis-UCD Campus 07/30/2013 02/14/2013 07/30/2013

Echo Summit (seasonal) 06/13/2013 - -

Fort Bragg – 300 Dana Street - 06/06/2013 12/09/2013

Glenbrook 08/28/2013 02/28/2013 08/28/2013

Grass Valley-Litton Building 03/19/2013 03/19/2013 09/27/2013

Gridley - 05/22/2013 11/26/2013

Guerneville-Church and 1st - 06/05/2013 12/10/2013

Healdsburg - Matheson - 06/05/2013 12/10/2013

Healdsburg-Municipal Airport 06/05/2013 - -

Hesperia-Olive Street 02/26/2013 02/26/2013 08/06/2013

Jackson-Clinton Road 05/29/2013 - -

Jerseydale 11/01/2013 - -

Joshua Tree National Monument 08/06/2013 - -

Joshua Tree – Pinto Wells 08/06/2013 - -

Joshua Tree - Cottonwood 08/07/2013 - -

Lakeport – Lakeport Blvd 08/29/2013 02/28/2013 08/29/2013

Lancaster – Division Street 02/21/2013 02/21/2013 08/06/2013

Lassen Volcanic National Park 04/09/2013 - -

Lucerne Valley - Middle School - 02/27/2013 08/07/2013

Mojave 02/05/2013 02/05/2013 08/28/2013

Paradise – Airport 07/10/2013 - -

Phelan – Beekley Road & Phelan 02/20/2013 - -

Placerville – Gold Nugget Way 06/12/2013 - -

Portola – Nevada Street - not yet operational 09/03/2013

Quincy – N Church Street - 03/13/2013 09/03/2013

Red Bluff – Main Street - 01/30/2013 07/08/2013

Red Bluff – Messer Drive - 01/30/2013 07/08/2013

Red Bluff – Oak Street Name 07/08/2013 - -

Redding – Health Department 04/09/2013 04/09/2013 10/01/2013

Ridgecrest – California Ave - 02/05/2013 08/28/2013

Roseville – N Sunrise Blvd 07/29/2013 02/11/2013 07/29/2013

San Andreas – Gold Strike Road 05/30/2013 05/30/2013 11/25/2013

Shasta Lake – Lake Blvd 04/08/2013 - -

Shasta Lake – La Mesa - 04/08/2013 10/01/2013

Sonora – Barretta Street 05/29/2013 - -

South Lake Tahoe – Sandy Way - 06/13/2013 12/02/2013

Sutter Buttes (seasonal) 05/13/2013 - -

Trona – Athol/Telescope #2 10/16/2013 04/23/2013 10/16/2013

Truckee - Fire Station - 03/12/2013 09/03/2013

Tuscan Butte (seasonal) 05/15/2013 - -

_______________________________________________________________________

48 Annual Monitoring Network Report for Twenty-three Districts in California
Site Name Gaseous Audit First Flow Audit Second Flow Audit

Ukiah – Gobbi Street 06/06/2013 - -

Ukiah – Library - 06/06/2013 12/09/2013

Vacaville – Merchant Street - 02/04/2013 07/18/2013

Vacaville – Ulatis Drive 07/18/2013 - -

Victorville – Park Avenue 02/28/2013 02/28/2013 08/06/2013

West Sacramento – 15th Street - 02/04/2013 07/17/2013

White Cloud (seasonal) 09/04/2013 - -

Willits – Justice Center - 06/06/2013 12/09/2013

Willows – Colusa 07/16/2013 02/05/2013 07/16/2013

Woodland – Gibson Road 07/17/2013 02/05/2013 07/17/2013

Yosemite Natl Park – Turtleback 11/18/2013 - -

Yosemite Village – Visitor Center - 04/08/2013 11/18/2013*

Yreka 10/02/2013 04/10/2013 10/02/2013

Yuba City 07/11/2013 01/29/2013 07/11/2013

Note:

*Due to Rim Fire the semi-annual flow audit at Yosemite Village could not be scheduled and 

audited within the 5 to 7 month interval requirement.

Table 15

2013 Gaseous Inlet Probe Residence Time

Site Name

Gaseous Residence Time (seconds)

Ozone Nitrogen 

Dioxide

Carbon 

Monoxide

Sulfur

Dioxide

Hydrogen 

Sulfide

Middletown-Anderson Springs - - - - 3.7

Anderson-North Street 6.9 - - - -

Auburn – Atwood Road 17.1 - - - -

Barstow - 12.4 - - -

Blythe-Murphy Street 17.7 - - - -

Chico – East Avenue 12.1 14.2 - - -

Colfax-City Hall 14.2 - - - -

Colusa-Sunrise Blvd 6.9 - - - -

Cool (seasonal) 11.0 - - - -

Davis-UCD Campus 16.7 16.8 - - -

Echo Summit (seasonal) 12.1 - - - -

Glenbrook - - - - 5.3

Grass Valley-Litton Building 7.2 - - - -

Healdsburg-Municipal Airport 14.2 - - - -

Hesperia-Olive Street 5.0 - - - -

Jackson-Clinton Road 5.0 - - - -

Jerseydale 15.8 - - - -

_______________________________________________________________________

49 Annual Monitoring Network Report for Twenty-three Districts in California
Site Name

Gaseous Residence Time (seconds)

Ozone Nitrogen 

Dioxide

Carbon 

Monoxide

Sulfur

Dioxide

Hydrogen 

Sulfide

Joshua Tree National Monument 4.0 - - - -

Joshua Tree – Pinto Wells 4.3 - - - -

Joshua Tree - Cottonwood 7.1 - - - -

Lakeport – Lakeport Blvd 13.5 - - - -

Lancaster – Division Street 14.0 15.7 14.0 - -

Lassen Volcanic National Park 9.3 - - - -

Mojave 8.3 - - - -

Paradise – Airport 11.7 - - - -

Phelan – Beekley Road & 

Phelan 6.4 - - - -

Placerville – Gold Nugget Way 6.3 - - - -

Red Bluff – Oak Street Name 12.7 - - - -

Redding – Health Department 7.6 - - - -

Roseville – N Sunrise Blvd 18.4 18.7 - - -

San Andreas – Gold Strike Road 8.9 - - - -

Shasta Lake – Lake Blvd 18.0 - - - -

Sonora – Barretta Street 9.1 - - - -

Sutter Buttes (seasonal) 9.2 - - - -

Trona – Athol/Telescope #2 7.9 10.0 - 8.3 8.7

Tuscan Butte (seasonal) 6.9 - - - -

Ukiah – Gobbi Street 16.6 - - - -

Vacaville – Ulatis Drive 4.3 - - - -

Victorville – Park Avenue 15.3 13.4 11.9 12.3 -

White Cloud (seasonal) 15.9 - - - -

Willows – Colusa 5.8 - - - -

Woodland – Gibson Road 6.5 - - - -

Yosemite Natl Park – Turtleback 9.9 - - - -

Yreka 4.8 - - - -

Yuba City 7.5 8.4 - - -

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50 Annual Monitoring Network Report for Twenty-three Districts in California
Section 8. Operating schedules

The CFR requires that the annual network plan include information about 

operating schedules. While gaseous monitors (e.g., O3, CO, NO2, SO2) and 

particulate monitoring with FEMs usually operate continuously throughout the

year, particulate monitoring with FRMs often operate one day out of every three 

days or one day out of every six days. The primary reason why particulate FRMs

operate less frequently is that the particulate FRMs are filter-based and therefore

much more labor intensive, requiring that field staff frequently retrieve and 

replace filters and that laboratory staff pre- and post-weigh filters. The 

continuous gaseous and particulate monitors produce hourly measurements of 

the gaseous and particulate pollutants, while the particulate filter-based monitors 

produce 24-hour measurements of particulate pollutants.

Particulate matter operating schedules

Current operating schedules for PM2.5 FRM monitors in the areas included in this 

report are listed in Table 16. These schedules were obtained from the U.S. EPA’s 

AQS database. In March 2014, the U.S. EPA provided to ARB an annual network 

plan checklist which includes a finding that requests ARB add the most recent 

design values for the PM2.5 FRM monitors that are covered in this report which

are operating on a 1-in-6 day schedule. Design values of the PM2.5 monitoring 

sites included in this plan are also included in Table 16. Note that exceptional 

events are included in the determination of the design values. In addition, on 

August 5, 2013, ARB formally requested approval from the U.S. EPA for the 

reduction of the sampling frequency for the PM2.5 FRM monitors covered in this 

report. The letter requesting U.S. EPA approval is attached in Appendix C. At 

the time this report was drafted, ARB has not received a formal response from 

the U.S. EPA regarding the approval request.

While there are a number of continuous PM2.5 monitors deployed, most of these 

are not federal equivalent methods (FEM). In March of 2008, U.S. EPA approved 

the first continuous PM2.5 FEM. Then on June 2009 and March 2011, U.S. EPA 

approved two more continuous PM2.5 FEMs. At the time this report was drafted, 

in the ARB PQAO, there are 34 continuous PM2.5 FEM sites. 

Operating schedules for the manual PM10 samplers in the areas included in this 

report all operate on a 1-in-6 day schedule. Similar to the PM2.5 FRM monitors, 

the 1-in-6 day schedule of the PM10 FRM monitors must also meet certain 

monitoring criteria. To determine whether the PM10 FRM monitors covered in the 

scope of this plan also meet the 1-in-6 day schedule, EPA requested the 

maximum concentrations of the PM10 FRM sites. Table 17 lists the PM10 FRM 

sites covered in this plan along with the 2013 PM10 maximum concentrations.

Note that exceptional events are included in the determination of the maximum 

concentrations. 

_______________________________________________________________________

51 Annual Monitoring Network Report for Twenty-three Districts in California
There are also nine continuous PM10 monitors operating in the area that this 

report covers, which are reporting data into AQS. These monitors are located at 

the South Lake Tahoe, Fort Bragg, Mojave, Lancaster, Trona, Willows, Barstow, 

Hesperia and Victorville sites. These continuous PM10 monitors are FEMs and 

are either BAM or TEOM monitors.

Table 16

Current PM2.5 FRM Operating Schedules and Design Values

(Monitors of the air districts included in this report)

Site Name

AQS Site 

Number

Current 

Schedules

2013 Design Values 

24hr / Ann. Avg. (ug/m3)

Chico-East 060070008 Everyday 34 / 10.1

Colusa-Sunrise Blvd 060111002 1 in 6 day 24 / 7.1

Grass Valley-Litton Building 060570005 1 in 6 day 15 / 4.6

Lakeport-Lakeport Blvd 060333001 1 in 6 day 10 / 3.7

Lancaster-43301 Division St 060379033 1 in 6 day 25 / 6.1

Portola-222 1st Avenue 060631007 1 in 3 day 37 / 12.8

Quincy-N Church Street 060631006 1 in 3 day 36 / 10.2

Redding-Health Department Roof 060890004 1 in 6 day 17 / 5.7

Ridgecrest-100 West California 060290015 1 in 6 day 11 / 5.4

Roseville-N Sunrise Blvd 060610006 1 in 6 day 19 / 7.5

Truckee-Fire Station 060571001 1 in 3 day 21 / 7

Victorville-14036 Park Ave 060710306 1 in 6 day 13 / 6.8

Woodland-Gibson Road 061131003 1 in 6 day 21 / 7.2

Yreka-Foothill Drive 060932001 1 in 6 day 26 / 6.3

Yuba City-Almond Street 061010003 Everyday 29 / 7.7

_______________________________________________________________________

52 Annual Monitoring Network Report for Twenty-three Districts in California
Table 17

Maximum Concentrations of the PM10 FRM Sites Covered in this Plan

Site Name

AQS Site 

Number

2013 24-hr max 

conc. (ug/m3)

Anderson 060890007 40.5

Auburn 060610002 79.5

Canebrake 060290017 43.3

Chico 060070008 59.0

Cloverdale 060970001 24.0

Colfax 060610004 57.5

Colusa 060111002 73.4

Guerneville 060973002 37.0

Healdsburg 060970002 54.0

Lucerne Valley 060710013 13.0

Red Bluff 061030002 54.5

Redding 060890004 29.5

Roseville 060610006 55.5

San Andreas 060090001 55.6

Shasta Lake 060890008 45.5

Vacaville 060953001 35.4

West Sacramento 061132001 62.4

Woodland 061131003 60.3

Yosemite Village 060431001 102.1

Yreka 060932001 54.6

Yuba City 061010003 56.1

Notes: 

The PM10 FRM monitors at Glenbrook (060333011), Lakeport (060333001), and Middletown 

(060333010) were not included in this table because these monitors report PM10 data in local 

conditions (i.e., 85101) and not in standard conditions (i.e., 81102). PM10 data is required to be 

reported in standard conditions for NAAQS comparison. 

Ozone operating schedules

While most ozone monitors operate continuously all year, a small number of 

ozone sites in the areas included in this report operate only in the warmer six 

months of the year. Several of these sites are at higher elevation where access 

during the winter can be problematic. Also, for most of the State, ozone is a 

summertime problem and concentrations during the winter are well below the 

levels of the ambient air quality standards. The following seasonal ozone sites in 

the areas included in this report all operate from May through October:

Cool (El Dorado County)

Echo Summit (El Dorado County)

Jerseydale (Mariposa County)

Sutter Buttes (Sutter County)

Tuscan Butte (Tehama County)

White Cloud (Nevada County)

_______________________________________________________________________

53 Annual Monitoring Network Report for Twenty-three Districts in California
In March 2013, EPA provided to ARB an annual network plan checklist which 

includes a finding that requires ARB to justify the monitoring schedule of the 

seasonal ozone sites that are covered in this report. Federal regulations require 

that ozone monitors operate every day, from January through December, unless 

certain monitoring criteria are met and U.S. EPA approves the seasonal 

schedule. ARB sent a request to the U.S. EPA on June 5, 2013, asking for 

approval of the monitoring schedule of the seasonal ozone sites covered in this 

report. On July 17, 2013, U.S. EPA approved the request. The approval letter is 

attached in Appendix C of this report.

_______________________________________________________________________

54 Annual Monitoring Network Report for Twenty-three Districts in California
Section 9. Additional information on PM2.5 monitors

This section includes information for two required annual network plan elements 

that relate specifically to PM2.5 and do not fit well elsewhere in the report. One 

required element relates to whether data for a PM2.5 monitor can be used to 

determine compliance with the national annual PM2.5 air quality standard. In the 

CFR, this is termed as the suitability for comparison to the annual standard. The 

other element requires including in the annual network plan information regarding 

the review process followed by air agencies when changes are made to the 

location of a PM2.5 monitor that is violating a PM2.5 standard.

9.1 Suitability for comparison to the annual PM2.5 standard

The CFR states that for PM2.5 FRM or FEM monitors used in area-wide 

monitoring, and that meet siting criteria, the reported data are comparable to the 

annual PM2.5 standard. For a PM2.5 monitor to be considered area-wide, the 

concentration values measured by the monitor should be representative of 

concentrations expected over an area with dimensions of a few kilometers. The 

PM2.5 FRM and FEM monitors included in this report are sited per the definition of

area-wide monitoring in the CFR and meet applicable requirements; therefore,

the FRM and FEM data are suitable for comparison to the PM2.5 NAAQS. 

9.2 Review of changes to PM2.5 network

The PM2.5 network of FRM monitors in California was largely established in 1999 

and completed in 2000. Little has changed in the siting of the FRM monitoring 

network between then and now. However, between 2008 and 2011, U.S. EPA 

approved three types of PM2.5 FEMs, which are Met One (method 170), GRIMM 

(method 195) and Thermo (method 181). At the time this report was drafted, four

agencies (ARB, Mendocino County, Placer County and Tehama County) in the 

areas covered by this report have submitted data from these monitors to the AQS 

database. 

As part of ARB’s ongoing oversight process, ARB requests the opportunity to 

review and comment on the possible regulatory consequences of any proposal to 

move or discontinue a monitor for any pollutant that violates a national or State 

air quality standard. Furthermore, when a local agency proposes to move or 

discontinue a monitor indicating the highest concentrations of a pollutant in an 

area, ARB requests that the agency conduct a period of concurrent or parallel

monitoring at that site and at the replacement site being proposed to represent 

the area as the required high site for the pollutant. This is expected even when 

the site is close to but not exceeding any standard for the pollutant. The parallel

monitoring is typically for a period of many months or a year, depending on the 

pollutant, the standard that is of most concern, and other factors. In addition,

ARB utilizes the annual network plan process to document and provide the public 

opportunities to comment on any proposed changes to the monitoring network. 

Any received comments are formally addressed via letters and are documented 

_______________________________________________________________________

55 Annual Monitoring Network Report for Twenty-three Districts in California
in the network plan. The network plan is submitted to the U.S. EPA annually for 

formal approval of all network modifications, including changes to the PM2.5

network.

_______________________________________________________________________

56 Annual Monitoring Network Report for Twenty-three Districts in California
Section 10. Proposed and recently implemented monitoring site changes

This section lists the proposed and recently implemented monitoring site 

changes in the areas included in this report, as well as changes to the monitoring 

sites that the ARB operates in areas outside the stated geographical scope of this 

report. Proposed monitoring site changes include proposals by the ARB or by 

districts that are covered in this report to add, remove, or move sites and/or 

monitors in the monitoring network before the end of 2015. Recently 

implemented monitoring changes include deployed and/or terminated sites and 

monitors in the monitoring network that the ARB has become aware of since last 

year’s report. Listed below are the proposed and implemented changes to the 

monitoring network that ARB is aware of at this time.

Proposed or Implemented ARB Changes:

The ARB recently terminated the Point Reyes site (060410003) in December 

2013. The only monitor operating at the Point Reyes site is a 

PM2.5 non-FEM BAM of which EPA approval is not needed for the termination. In 

addition, ARB replaced the PM2.5 non-FEM BAM at the Sacramento-T Street site 

(060670010) with a PM2.5 FEM BAM on May 20, 2014. Finally, in 2013, ARB 

replaced the PM10 FRM monitor at the Willows site (060210003) with a 

continuous PM10 BAM monitor.

Proposed or Implemented District Changes:

The Antelope Valley APCD plans to replace the PM2.5 FRM monitor at the 

Lancaster site (060379033) with a continuous PM2.5 FEM BAM by the end of 

2014. In addition, the PM10 FRM monitor at this site was replaced with a 

continuous PM10 BAM on January 1, 2013. Note that while the Lancaster site is 

owned and operated by the Antelope Valley APCD, it is the Mojave Desert AQMD 

that maintains the site and monitors. Moreover, Mojave Desert AQMD is also 

responsible for the data submittals at Lancaster.

The Mojave Desert AQMD replaced the PM10 FRM monitors at the Barstow

(060710001), Hesperia (060714001), Trona (060711234) and Victorville 

(060710306) sites with continuous PM10 BAM monitors between late 2013 and 

early 2014. EPA approval was not needed for the PM10 monitor replacements. 

In addition, Mojave Desert AQMD plans to replace the PM10 FRM with a 

continuous PM10 BAM at Lucerne Valley (060710013) in August 2014. Mojave 

Desert AQMD wants to transition its PM10 FRM network to a continuous PM10

BAM network and anticipates submitting both standard and local conditions PM10

BAM data from its network. Finally, the district plans to replace one of the PM2.5

FRM monitors at the Victorville site with a continuous PM2.5 FEM BAM by the end 

of 2014.

The Northern Sierra AQMD relocated the Portola-Nevada Street site 

(060631009) to a new location on 420 Gulling Street in August 2013. The new 

_______________________________________________________________________

57 Annual Monitoring Network Report for Twenty-three Districts in California
site is called Portola-Gulling Street (060631010). U.S. EPA approved the 

relocation on December 11, 2013. The approval letter is attached in Appendix C.

The Northern Sonoma APCD replaced the PM10 FRM monitors at the Cloverdale 

(060970001), Guerneville (060973002), and Healdsburg (060970002) sites with

continuous PM10 BAM monitors in 2013. EPA approval of the monitor transitions 

was not needed because these changes weren’t monitor closures. The District 

submitted the PM10 BAM data into AQS effective January 1, 2014. 

In the 2013 ARB annual network plan, the Placer County APCD proposed a new 

monitoring site in Tahoe City. The Tahoe City site (060611004) is now 

completed and began sampling in November 2013. Ozone and continuous

PM2.5 non-FEM BAM data are being reported from this site to AQS. The ozone 

monitor is designated as a SLAMS monitor in AQS. For this reason, U.S. EPA 

approval of the SLAMS ozone monitor is required. The District is currently 

drafting the approval request. In addition, Placer County APCD is proposing to 

terminate the PM10 monitors at the Auburn (060610002) and Colfax (060610004) 

sites in Placer County. The District will also be asking for U.S. EPA approval of 

these closures. Finally, the District relocated the ozone monitor at the

Auburn-Dewitt C-Avenue site (060610002) to the Auburn-11645 Atwood Road 

site (060610003) in June 2011 and the ozone monitor at the Lincoln-L Street site 

(060612001) to the Lincoln-1st Street site (060612002) in September 2012.

U.S. EPA approvals of these relocations are needed. The District letter 

requesting U.S. EPA approval is included in Appendix C of this report.

The Siskiyou County APCD plans to add a continuous PM2.5 FEM BAM at the 

Yreka site (060932001) and re-designate the existing PM2.5 FRM monitor as the 

quality assurance monitor at this site.

The Tehama County APCD plans to relocate the ozone, PM2.5 FEM BAM, and 

PM10 monitors from three different locations in the city of Red Bluff to a central 

location in the same city consolidating all monitoring at the new district 

headquarters by the end of 2015. The new location is approximately two miles 

northwest of the current location.

_______________________________________________________________________

58 Annual Monitoring Network Report for Twenty-three Districts in California
Section 11. Access to more information about the network

While this report includes a great deal of information about the ambient air quality 

monitoring network, much more information is readily available, including 

summaries of the pollutant data from the monitors around the State. Much of this 

information is available on the web. This section lists a number of additional 

sources of such information. Also listed is contact information for the agencies 

responsible for the monitoring covered in this report.

ARB’s Monitoring and Laboratory Division (MLD) maintains web pages with 

information about all the existing monitoring sites that routinely monitor and 

submit air quality data in California. The pages also include detailed local maps 

showing the location of the sites. This information can be found at: 

http://www.arb.ca.gov/aaqm/mldaqsb/amn.htm. A more general MLD web page 

that provides links to other aspects of ambient monitoring is located at:

http://www.arb.ca.gov/aaqm/aaqm.htm.

Summaries of the official air quality data from sites around the State can be found 

at: http://www.arb.ca.gov/adam/welcome.html. Summaries of the most recent 

preliminary data can be viewed at: http://www.arb.ca.gov/aqd/aqinfo.htm. These 

last two sources of information are maintained by ARB staff of the Air Quality 

Planning and Science Division, as is the following more general web page that 

lists links to other aspects of the ambient air quality data program: 

http://www.arb.ca.gov/aqd/aqdpage.htm.

_______________________________________________________________________

59 Annual Monitoring Network Report for Twenty-three Districts in California
Agency contacts for ARB

Regarding this report and questions relating to the collected ambient air quality 

data:

Pheng Lee, Air Pollution Specialist, plee@arb.ca.gov, (916) 445-6059

Regarding the collection of the ambient data:

Ken Stroud, Chief, Air Quality Surveillance Branch, kstroud@arb.ca.gov, 

(916) 324-7591

Regarding quality oversight of the monitoring program:

Mike Miguel, Chief, Quality Management Branch, mmiguel@arb.ca.gov,

(916) 322-0960

Agency contacts for the air districts covered in this report

Amador County Air Pollution Control District, Jackson, CA

Mike Boitano, Air Pollution Control Officer

AirDistrict@co.amador.ca.us

(209) 257-0112

Antelope Valley Air Quality Management District, Lancaster, CA

Eldon Heaston, Air Pollution Control Officer (also APCO for Mojave Desert)

eheaston@mdaqmd.ca.gov

(661) 723-8070

Butte County Air Quality Management District, Chico, CA

James Wagoner, Air Pollution Control Officer

jwagoner@bcaqmd.org

(530) 332-9400

Calaveras County Air Pollution Control District, San Andreas, CA

Brian Moss, Air Pollution Control Officer

bmoss@co.calaveras.ca.us

(209) 754-6504

Colusa County Air Pollution Control District, Colusa, CA

Joe Damiano, Air Pollution Control Officer

jdamiano@countyofcolusa.org

(530) 458-0590

Eastern Kern Air Pollution Control District, Bakersfield, CA

Glen Stephens, Air Pollution Control Officer

glens@co.kern.ca.us

(661) 862-5250

_______________________________________________________________________

60 Annual Monitoring Network Report for Twenty-three Districts in California
El Dorado County Air Quality Management District, Placerville, CA

Dave Johnston, Air Pollution Control Officer

dave.johnston@edcgov.us

(530) 621-5896

Feather River Air Quality Management District, Yuba City, CA

Christopher D. Brown, Air Pollution Control Officer

apco@fraqmd.org

(530) 634-7659 x 203

Glenn County Air Pollution Control District, Willows, CA

Jim Donnelly, Air Pollution Control Officer

jdonnelly@countyofglenn.net

(530) 934-6500

Lake County Air Quality Management District, Lakeport, CA

Douglas Gearhart, Air Pollution Control Officer

dougg@lcaqmd.net

(707) 263-7000

Lassen County Air Pollution Control District, Susanville, CA

Dan Newton, Air Pollution Control Officer

dnewton@cityofsusanville.org

(530) 257-1045

Mariposa County Air Pollution Control District, Mariposa, CA

Dr. Charles Mosher, Air Pollution Control Officer

air@mariposacounty.org

(209) 966-2220

Mendocino County Air Quality Management District, Ukiah, CA

Robert A. Scaglione, Air Pollution Control Officer

mcaqmd@co.mendocino.ca.us

(707) 463-4354

Modoc County Air Pollution Control District, Alturas, CA

Joe Moreo, Air Pollution Control Officer

apcd@modoccounty.us

(530) 233-5522

Mojave Desert Air Quality Management District, Lancaster, CA

Eldon Heaston, Air Pollution Control Officer (also APCO for Antelope Valley)

eheaston@mdaqmd.ca.gov

(661) 723-8070

Northern Sierra Air Quality Management District, Grass Valley, CA

_______________________________________________________________________

61 Annual Monitoring Network Report for Twenty-three Districts in California
Gretchen Bennitt, Air Pollution Control Officer

Gretchen@myairdistrict.com

(530) 274-9360

Northern Sonoma County Air Pollution Control District, Healdsburg, CA

Barbara Lee, Air Pollution Control Officer

nsc@sonic.net

(707) 433-5911

Placer County Air Pollution Control District, Auburn, CA

Tom Christofk, Air Pollution Control Officer

pcapcd@placer.ca.gov

(530) 745-2330

Shasta County Air Quality Management District, Redding, CA

Richard W. Simon, Air Pollution Control Officer

rsimon@co.shasta.ca.us

(530) 225-5789

Siskiyou County Air Pollution Control District, Yreka, CA

Patrick Griffin, Air Pollution Control Officer

pgriffin@co.siskiyou.ca.us

(530) 841-4031

Tehama County Air Pollution Control District, Red Bluff, CA

Alan Abbs, Air Pollution Control Officer

aabbs@tehcoapcd.net

(530) 527-3717

Tuolumne County Air Pollution Control District, Columbia, CA

Vicky Helmar, Air Pollution Control Officer

vhelmar@co.tuolumne.ca.us

(209) 533-5693

Yolo-Solano Air Quality Management District, Davis, CA

Mat Ehrhardt, Air Pollution Control Officer

meharhard@ysaqmd.org

(530) 757-3673

_______________________________________________________________________

62 Annual Monitoring Network Report for Twenty-three Districts in California
APPENDIX A

Regulatory language of 40 CFR 58.10

§ 58.10 Annual monitoring network plan and periodic network assessment.

(a)(1) Beginning July 1, 2007, the State, or where applicable local, agency 

shall adopt and submit to the Regional Administrator an annual monitoring 

network plan which shall provide for the establishment and maintenance of an air 

quality surveillance system that consists of a network of SLAMS monitoring 

stations including FRM, FEM, and ARM monitors that are part of SLAMS, NCore 

stations, STN stations, State speciation stations, SPM stations, and/or, in serious, 

severe and extreme ozone nonattainment areas, PAMS stations, and SPM 

monitoring stations. The plan shall include a statement of purposes for each 

monitor and evidence that siting and operation of each monitor meets the 

requirements of appendices A, C, D, and E of this part, where applicable. The 

annual monitoring network plan must be made available for public inspection for 

at least 30 days prior to submission to EPA.

(2) Any annual monitoring network plan that proposes SLAMS network 

modifications (including new monitoring sites, new determinations that data are 

not of sufficient quality to be compared to the NAAQS, and changes in 

identification of monitors as suitable or not suitable for comparison against the 

annual PM 2.5 NAAQS) is subject to the approval of the EPA Regional 

Administrator, who shall provide opportunity for public comment and shall 

approve or disapprove the plan and schedule within 120 days. If the State or 

local agency has already provided a public comment opportunity on its plan and 

has made no changes subsequent to that comment opportunity, and has 

submitted the received comments together with the plan, the Regional 

Administrator is not required to provide a separate opportunity for comment.

(3) The plan for establishing required NCore multipollutant stations shall be 

submitted to the Administrator not later than July 1, 2009. The plan shall provide 

for all required stations to be operational by January 1, 2011.

(4) A plan for establishing source-oriented Pb monitoring sites in accordance 

with the requirements of appendix D to this part for Pb sources emitting 1.0 tpy or 

greater shall be submitted to the EPA Regional Administrator no later than July 1, 

2009, as part of the annual network plan required in paragraph (a)(1) of this 

section. The plan shall provide for the required source-oriented Pb monitoring 

sites for Pb sources emitting 1.0 tpy or greater to be operational by January 1, 

2010. A plan for establishing source-oriented Pb monitoring sites in accordance 

with the requirements of appendix D to this part for Pb sources emitting equal to 

or greater than 0.50 tpy but less than 1.0 tpy shall be submitted to the EPA 

Regional Administrator no later than July 1, 2011. The plan shall provide for the 

required source-oriented Pb monitoring sites for Pb sources emitting equal to or 

greater than 0.50 tpy but less than 1.0 tpy to be operational by December 27, 

2011.

_______________________________________________________________________

63 Annual Monitoring Network Report for Twenty-three Districts in California
(5)(i) A plan for establishing or identifying an area-wide NO2 monitor, in 

accordance with the requirements of Appendix D, section 4.3.3 to this part, shall 

be submitted as part of the Annual Monitoring Network Plan to the EPA Regional 

Administrator by July 1, 2012. The plan shall provide for these required monitors 

to be operational by January 1, 2013.

(ii) A plan for establishing or identifying any NO2 monitor intended to 

characterize vulnerable and susceptible populations, as required in Appendix D, 

section 4.3.4 to this part, shall be submitted as part of the Annual Monitoring 

Network Plan to the EPA Regional Administrator by July 1, 2012. The plan shall 

provide for these required monitors to be operational by January 1, 2013.

(iii) A plan for establishing a single near-road NO2 monitor in CBSAs having 

1,000,000 or more persons, in accordance with the requirements of Appendix D, 

section 4.3.2 to this part, shall be submitted as part of the Annual Monitoring 

Network Plan to the EPA Regional Administrator by July 1, 2013. The plan shall 

provide for these required monitors to be operational by January 1, 2014.

(iv) A plan for establishing a second near-road NO2 monitor in any CBSA 

with a population of 2,500,000 or more persons, or a second monitor in any 

CBSA with a population of 500,000 or more persons that has one or more 

roadway segments with 250,000 or greater AADT counts, in accordance with the 

requirements of Appendix D, section 4.3.2 to this part, shall be submitted as part 

of the Annual Monitoring Network Plan to the EPA Regional Administrator by July 

1, 2014. The plan shall provide for these required monitors to be operational by 

January 1, 2015.

(v) A plan for establishing a single near-road NO2 monitor in all CBSAs 

having 500,000 or more persons, but less than 1,000,000, not already required 

by paragraph (a)(5)(iv) of this section, in accordance with the requirements of 

Appendix D, section 4.3.2 to this part, shall be submitted as part of the Annual 

Monitoring Network Plan to the EPA Regional Administrator by July 1, 2016. The 

plan shall provide for these monitors to be operational by January 1, 2017.

(6) A plan for establishing SO2 monitoring sites in accordance with the 

requirements of appendix D to this part shall be submitted to the EPA Regional 

Administrator by July 1, 2011 as part of the annual network plan required in 

paragraph (a) (1). The plan shall provide for all required SO2 monitoring sites to 

be operational by January 1, 2013.

(7) A plan for establishing CO monitoring sites in accordance with the 

requirements of appendix D to this part shall be submitted to the EPA Regional 

Administrator. Plans for required CO monitors shall be submitted at least six 

months prior to the date such monitors must be established as required by 

section 58.13.

_______________________________________________________________________

64 Annual Monitoring Network Report for Twenty-three Districts in California
(8)(i) A plan for establishing near-road PM 2.5 monitoring sites in CBSAs 

having 2.5 million or more persons, in accordance with the requirements of 

appendix D to this part, shall be submitted as part of the annual monitoring 

network plan to the EPA Regional Administrator by July 1, 2014. The plan shall 

provide for these required monitoring stations to be operational by January 1, 

2015.

(ii) A plan for establishing near-road PM 2.5 monitoring sites in CBSAs having 

1 million or more persons, but less than 2.5 million persons, in accordance with 

the requirements of appendix D to this part, shall be submitted as part of the 

annual monitoring network plan to the EPA Regional Administrator by July 1, 

2016. The plan shall provide for these required monitoring stations to be 

operational by January 1, 2017.

(b) The annual monitoring network plan must contain the following 

information for each existing and proposed site:

(1) The AQS site identification number.

(2) The location, including street address and geographical coordinates.

(3) The sampling and analysis method(s) for each measured parameter.

(4) The operating schedules for each monitor.

(5) Any proposals to remove or move a monitoring station within a period of 

18 months following plan submittal.

(6) The monitoring objective and spatial scale of representativeness for each 

monitor as defined in appendix D to this part.

(7) The identification of any sites that are suitable and sites that are not 

suitable for comparison against the annual PM 2.5 NAAQS as described in § 

58.30.

(8) The MSA, CBSA, CSA or other area represented by the monitor.

(9) The designation of any Pb monitors as either source-oriented or nonsource-oriented according to Appendix D to 40 CFR part 58.

(10) Any source-oriented monitors for which a waiver has been requested or 

granted by the EPA Regional Administrator as allowed for under paragraph 

4.5(a)(ii) of Appendix D to 40 CFR part 58.

(11) Any source-oriented or non-source-oriented site for which a waiver has 

been requested or granted by the EPA Regional Administrator for the use of 

_______________________________________________________________________

65 Annual Monitoring Network Report for Twenty-three Districts in California
Pb-PM10 monitoring in lieu of Pb-TSP monitoring as allowed for under paragraph 

2.10 of Appendix C to 40 CFR part 58.

(12) The identification of required NO2 monitors as near-road, area-wide, or 

vulnerable and susceptible population monitors in accordance with Appendix D, 

section 4.3 of this part.

(13) The identification of any PM 2.5 FEMs and/or ARMs used in the 

monitoring agency's network where the data are not of sufficient quality such that 

data are not to be compared to the NAAQS. For required SLAMS where the 

agency identifies that the PM 2.5 Class III FEM or ARM does not produce data of 

sufficient quality for comparison to the NAAQS, the monitoring agency must 

ensure that an operating FRM or filter-based FEM meeting the sample frequency 

requirements described in § 58.12 or other Class III PM 2.5 FEM or ARM with data 

of sufficient quality is operating and reporting data to meet the network design 

criteria described in appendix D to this part.

(c) The annual monitoring network plan must document how state and local 

agencies provide for the review of changes to a PM 2.5 monitoring network that 

impact the location of a violating PM 2.5 monitor. The affected state or local 

agency must document the process for obtaining public comment and include 

any comments received through the public notification process within their 

submitted plan.

(d) The state, or where applicable local, agency shall perform and submit to 

the EPA Regional Administrator an assessment of the air quality surveillance 

system every 5 years to determine, at a minimum, if the network meets the 

monitoring objectives defined in appendix D to this part, whether new sites are 

needed, whether existing sites are no longer needed and can be terminated, and 

whether new technologies are appropriate for incorporation into the ambient air 

monitoring network. The network assessment must consider the ability of existing 

and proposed sites to support air quality characterization for areas with relatively 

high populations of susceptible individuals (e.g., children with asthma), and, for

any sites that are being proposed for discontinuance, the effect on data users 

other than the agency itself, such as nearby states and tribes or health effects 

studies. The state, or where applicable local, agency must submit a copy of this 

5-year assessment, along with a revised annual network plan, to the Regional 

Administrator. The assessments are due every five years beginning July 1, 2010.

(e) All proposed additions and discontinuations of SLAMS monitors in annual 

monitoring network plans and periodic network assessments are subject to 

approval according to § 58.14.

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66 Annual Monitoring Network Report for Twenty-three Districts in California
APPENDIX B

For ozone, PM10, and PM2.5, the required minimum number of monitors are 

based on the population of the core-based statistical area (CBSA) and the 

severity of the air quality for the pollutant in the CBSA. The tables below list the 

CBSAs, population of the CBSAs, and the site in each CBSA that is currently 

measuring the highest concentration. In all cases, sufficient monitoring exists,

and no additional monitoring is required. 

Minimum Monitoring Requirements for O3, PM10, and PM2.5

Ozone

Minimum Monitoring Requirements for Ozone.

Bakersfield*^ Kern 839,361 0.089 Arvin-DiGiorgio 2 8 0

Chico Butte 220,000 0.076 Paradise-4405 Airport Road 1 2 0

Los Angeles-Long BeachAnahiem* Los Angeles and Orange 12,828,837 0.099 Santa Clarita 4 19 0

Redding Shasta 177,223 0.068 Shasta Lake-13791 Lake Blvd 1 4 0

Riverside-San BernardinoOntario* Riverside and San Bernardino 4,224,851 0.107 Crestline 3 21 0

Sacramento-Arden ArcadeRoseville*El Dorado, Placer, Sacramento, 

and Yolo 2,149,127 0.09 Folsom-Natoma Street 2 17 0

Santa Rosa* Sonoma 483,878 0.053 Santa Rosa-5 th Street^^ 1 2 0

Vallejo-Fairfield* Solano 413,344 0.067 Vacaville-Ulatis Drive 2 3 0

Yuba City Sutter and Yuba 166,892 0.073 Sutter Buttes^^^ 1 2 0

* Parts of these CBSAs are included in the geographical scope of this report, and parts are within the geographical scope of the reports being completed by the districts.

See Table 6a for the completed list of CBSAs in California. The numbers of active ozone monitors listed are for the entire CBSA (see below for site details). Only ozone

monitors that are part of the SLAMS and SPM networks are counted towards this monitoring requirement. Exceptional events are included in the determination of the design values.

^ The 3-year average of the 4th highest concentration usually represents the design value. Prior to 2012, the highest concentrations in the Bakersfield CBSA 

were measured at Arvin-Bear Mountain, which had a 2010 design value of 0.104 ppm. The monitor at Arvin-DiGiorgio, with a 3-year average of the fourth highest concentration

of 0.089 ppm, currently has the highest design value among sites with complete data over three years. 

^^ The design value for the Healdsburg-Municipal Airport site is likely higher than that for the Santa Rosa-5th Street site, but data are not complete for 2011-2013 at Healdsburg.

Nevertheless, the design value for the Healdsburg-Municipal Airport site was well below the level of the federal 8-hour standard in 2010 and for several years prior to that.

 ^^^ The Sutter Buttes site is a seasonal site (May-October). 2011 data are 79% complete during the 6-month monitoring period. 

Ozone sites which are counted towards minimum monitoring requirements.

CBSA Site CBSA Site CBSA Site

Arvin-DiGorgio Chico-East Auburn

Bakersfield-California Paradise Cool

Bakersfield-Municipal Airport Colfax

Edison CBSA Site Davis

Maricopa Anderson Echo Summit

Mojave Lassan Volcanic NP Elk Grove

Oildale Redding Folsom

Shafter Shasta Lake Lincoln

North Highlands

Anahiem Banning-Airport Placerville

Azusa Barstow Roseville

Burbank Blyth Sac-Del Paso

Compton Crestline Sac-Goldenland

Costa Mesa Elsinore Sac-T St

Glendora Fontana Sloughhouse

La Habra Hesperia Tahoe City 

Lancaster Indio Woodland

Long Beach Joshua Tree-Black Rock

Los Angeles-North Main Joshua Tree-Cottonwood CBSA Site

Los Angeles-Westchester Mira Loma Healdsburg

Mission Viejo Palm Springs Santa Rosa

North Long Beach Perris

Pasadena Phelan CBSA Site

Pico Riveria Redlands Vallejo

Pomona Riverside-Rubidoux Vacaville

Reseda San Bernardino Fairfield

Santa Clarita Trona

West Los Angeles Upland CBSA Site

Victorville Yuba City-Almond

Westchester Sutte Buttes Yuba City

Riverside-San 

Bernardino-Ontario

SacramentoArden 

ArcadeRoseville

VallejoFairfield

Bakersfield

Chico

Los Angeles-Long BeachAnahiem

Redding

Santa Rosa

# of Additonal 

Monitors Needed CBSA County(ies) Population (2010 Census)

3-Year Avg of the 

4th Highest 

Concentration

Site with the Highest 3-Yr 

Avg of the 4th Highest 

Concentration

# of 

Monitors 

Required

# of Active 

Monitors

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67 Annual Monitoring Network Report for Twenty-three Districts in California
PM2.51

Minimum Montoring Requirements for PM2.5 SLAMS.

Bakersfield* Kern 839,361 17.3 Bakersfield-410 E Planz 65 Bakersfield-California Ave 2 4 0

Chico Butte 220,000 10.1** Chico-East** 34** Chico-East** 1 1 0

Los Angeles-Long 

Beach-Anahiem* Los Angeles and Orange 12,828,837 12.5 Burbank & LA-North Main 31 Burbank & LA-North Main 3 12 0

Redding Shasta 177,223 5.7 Redding-Health Department 17 Redding-Health Department 0 1 0

Riverside-San 

Bernardino-Ontario*

Riverside and San 

Bernardino 4,224,851 14.8 Mira Loma Van Buren 37 Mira Loma Van Buren 3 10 0

Sacramento-Arden 

Arcade-Roseville*

El Dorado, Placer, 

Sacramento, and Yolo 2,149,127 10.4 Sacramento-DPM 36 Sacramento-DPM 3 6 0

Santa Rosa* Sonoma 483,878 8.5 Santa Rosa-5th St 22 Santa Rosa-5th St 0 1 0

Vallejo-Fairfield* Solano 413,344 9.6 Vallejo-304 Tuolumne St 30 Vallejo-304 Tuolumne St 0 2 0

Yuba City Sutter and Yuba 166,892 7.7 Yuba City-Almond 29 Yuba City-Almond 0 1 0

1

Design values are based on both FRM and FEM data. The total number of active PM2.5 monitors include both the filter-based FRMs and the continuous 

FEM PM2.5 monitors that are part of the SLAMS network. Exceptional events are included in the determination of the design values.

* Parts of these CBSAs are included in the geographical scope of this report, and parts are within the geographical scope of the reports being completed by the districts. 

See Table 6a for the completed list of CBSAs in California. The numbers of active PM2.5 SLAMS monitors listed are for the entire CBSA (see below for site details).

**The Chico-East site started on 4/2/2012. All monitors at the Chico-East site was relocated from the discontinued Chico-Manzanita site. The 2013 design values for the

Chico CBSA were computed by combining the PM2.5 data from the two Chico locations (i.e., Chico-Manzanita and Chico-East).

PM2.5 SLAMS sites for which are counted towards minimum monitoring requirements.

CBSA Site CBSA Site CBSA Site

Bakersfield-California Auburn

Bakersfield-E Planz Roseville

Mojave Sac-Del Paso

Ridgecrest CBSA Site Sac-Health

Sac-T St

CBSA Site Woodland

Anahiem

Azusa CBSA Site CBSA Site

Burbank Big Bear City

Compton Fontana

Lancaster Indio

Los Angeles-North Main Mira Loma CBSA Site

Mission Viejo Ontario Napa

North Long Beach Palm Springs Vallejo

Pasadena Riverside-Magnolia

Pico Riveria Riverside-Rubiduox CBSA Site

Reseda San Bernardino

South Long Beach Victorville

CBSA County(ies) Population 

(2010 Census)

3-year Highest 

Annual Design 

Value (ug/m3)

Site with the Highest 3-

year Annual Design 

Value

3-year Highest 

24-hr Design 

Value (ug/m3)

# of Active 

SLAMS 

Sites

# of Additional 

SLAMS Sites 

Needed

Site(s) with the 3-year 

Highest 24-hr Design 

Value

# of Required 

SLAMS Sites

Yuba CityAlmond

Santa Rosa

Vallejo-Fairfield

Bakersfield

Los Angeles-Long 

Beach-Anahiem

Chico-East

Redding Redding-Health Dept

Sacramento-Arden ArcadeRoseville

Chico

Santa Rosa

Yuba City

Riverside-San 

BernardinoOntario

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68 Annual Monitoring Network Report for Twenty-three Districts in California
Continuous PM2.51

Minimum Montoring Requirements for continuous PM2.5 monitors.

Bakersfield* Kern 839,361 Bakersfield-California Bakersfield-California 1 3 0

Chico Butte 220,000 Chico-East Chico-East 1 3 0

Los Angeles-Long 

Beach-Anahiem*

Los Angeles and 

Orange 12,828,837 Burbank & LA-North 

Main Burbank & LA-North Main 2 8 0

Redding Shasta 177,223 N/A N/A 0 0 0

Riverside-San 

Bernardino-Ontario*

Riverside and San 

Bernardino 4,224,851 Mira Loma Van Buren Mira Loma Van Buren 2 8 0

Sacramento-Arden 

Arcade-Roseville*

El Dorado, Placer, 

Sacramento, and 

Yolo

2,149,127 Davis-UCD Campus Sacramento-DPM 2 11 0

Santa Rosa* Sonoma 483,878 Santa Rosa-5th St Santa Rosa-5th St 0 1 0

Vallejo-Fairfield* Solano 413,344 Vallejo Vallejo 0 2 0

Yuba City Sutter and Yuba 166,892 Yuba City-Almond Yuba City-Almond 0 1 0

1

The CFR does not specify that continuous PM2.5 monitors have to be Federal Equivalent Methods (FEMs); therefore, this assessment includes both continuous 

FEM and non-FEM PM2.5 monitors.

* Parts of these CBSAs are included in the geographical scope of this report, and parts are within the geographical scope of the reports being completed by the districts.

See Table 6a for the completed list of CBSAs in California. The numbers of active continuous PM2.5 monitors listed are for the entire CBSA (see below for site details).

^ The required number of continuous PM2.5 monitor is one-half (round up) the total number of required PM2.5 SLAMS sites in each CBSA 

(40 CFR 58 Appendix A Section 4.7.2).

^^The number of active continuous PM2.5 monitors listed for each CBSA include both FEM and non-FEM monitors.

N/A means that there is no continuous PM2.5 monitor in the CBSA.

Continuous PM2.5 sites for which are counted towards minimum monitoring requirements.

CBSA Site CBSA Site CBSA Site

Bakersfield Redding -- Auburn

Lebec Colfax

Mojave CBSA Site Elk Grove

Banning-Airport Folsom

CBSA Site Crestline Lincoln

Anahiem Elsinor Roseville

Burbank Mira Loma Sac-Del Paso

Glendora Riverside-Magnolia Sac-T St

Los Angeles Riverside-Rubidoux Sloughhouse

North Long Beach Upland Tahoe City

Reseda Winchester Davis-UCD

Santa Clarita

South Long Beach

CBSA Site CBSA Site

CBSA Site Napa

Chico-East Vallejo

Gridley

Paradise CBSA Site

Yuba City Yuba City-Almond Vallejo-Fairfield

Chico

Los Angeles-Long 

Beach-Anahiem

SacramentoArden ArcadeRoseville

Santa Rosa

# of Additional 

Continuous 

Monitors Needed

CBSA County(ies) Population 

(2010 Census)

Site with the Highest 

Annual Design Value

Santa Rosa

Site with the Highest 24-

hr Design Value

# of Required 

Continuous 

Monitors^

Bakersfield

Riverside-San 

Bernardino-Ontario

# of Active 

Continuous 

Monitors^^

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69 Annual Monitoring Network Report for Twenty-three Districts in California
PM10

Minimum Montoring Requirements for PM10.

Bakersfield* Kern 839,361 134.3 Oildale 1-2 4 0

Chico Butte 220,000 59 Chico-East 0 1 0

Los Angeles-Long BeachAnahiem* Los Angeles and Orange 12,828,837 77** Anaheim** 2-4 10 0

Redding Shasta 177,223 45.5 Shasta Lake 0 3 0

Riverside-San BernardinoOntario*Riverside and San 

Bernardino 4,224,851 147 Mira Loma 6-10 17 0

Sacramento-Arden ArcadeRoseville*El Dorado, Placer, 

Sacramento, and Yolo 2,149,127 79.5 Auburn 2-4 11 0

Santa Rosa* Sonoma 483,878 54 Healdsburg 0-1 3 0

Vallejo-Fairfield* Solano 413,344 37.6 Napa 0-1 2 0

Yuba City Sutter and Yuba 166,892 56.1 Yuba City-Almond 0 1 0

* Parts of these CBSAs are included in the geographical scope of this report, and parts are within the geographical scope of the reports being completed 

by the districts. See Table 6a for the completed list of CBSAs in California. The numbers of active PM10 monitors listed are for the entire CBSA (see below 

for site details).

**The Lancaster site reported a max concentration of 185.4 ug/m3 on May 28, 2013. This was not corrobrated by the collocated sampler and is being investigated.

The next highest site for the Los Angeles-Long Beach-Anahiem CBSA is the Anaheim site. 

PM10 FRM sites for which are counted towards minimum monitoring requirements.

CBSA Site CBSA Site CBSA Site

Bakersfield-California Banning-Airport Auburn

Canebrake Barstow Colfax

Oildale Crestline North Highlands

Ridgecrest Fontana Roseville

Hesperia Sac-Branch

CBSA Site Indio Sac-Del Paso

Anahiem Lucerne Valley Sac-Goldenland

Azusa Mira Loma Sac-Health Dept

Burbank Norco Sac-T St

Lancaster Ontario West Sac

Los Angeles-North Main Palm Springs Woodland

Los Angeles-Westchester Perris

Mission Viejo Redlands

North Long Beach Riverside-Rubidoux CBSA Site

Santa Clarita San Bernardino Napa

South Long Beach Trona Vacaville

Victorville

CBSA Site

CBSA Site CBSA Site

Healdsburg

Cloverdale

Gunerneville

CBSA Site

Redding-Health Dept

Anderson

Shasta Lake

SacramentoArden 

ArcadeRoseville

Los Angeles-Long BeachAnahiem

Riverside-San 

Bernardino-Ontario

VallejoFairfield

Yuba City Yuba CityAlmond

Redding

Santa Rosa

Bakersfield

Chico Chico-East

# of 

Required 

Monitors

# of Active 

Monitors

# of Additional 

Monitors 

Needed

CBSA County(ies) Population 

(2010 Census)

2013 Max Daily 

Concentration 

(ug/m3)

Max Concentration Site

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70 Annual Monitoring Network Report for Twenty-three Districts in California
APPENDIX C

Supporting Documents included in the ANP

(For example, EPA approval letters)

1. July 17, 2013. U.S. EPA letter, approving the seasonal ozone monitoring 

sites included in this report.

2. August 5, 2013. ARB letter, requesting approval for the reduced sampling 

frequencies of the PM2.5 monitors covered in this plan.

3. December 11, 2013. U.S. EPA letter, approving the relocation of the 

Portola site in Plumas County.

4. June 25, 2014. Placer County APCD letter, requesting approval of the 

Auburn and Lincoln site relocations in Placer County.

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71 Annual Monitoring Network Report for Twenty-three Districts in California
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79 Annual Monitoring Network Report for Twenty-three Districts in California
APPENDIX D

List of Abbreviations and Acronyms

APCD Air Pollution Control District

AQMD Air Quality Management District

AQS Air Quality System

ARB Air Resources Board

CFR Code of Federal Regulations

CBSA Core-Based Statistical Area

FEM Federal equivalent method

FRM Federal reference method

MSA Metropolitan Statistical Area

NAAQS National Ambient Air Quality Standard

NO2 Nitrogen dioxide

Pb Lead

PM10 Particulate matter (0 to 10 microns aerodynamic diameter)

PM2.5 Particulate matter (0 to 2.5 microns aerodynamic diameter)

PQAO Primary quality assurance organization

 

SIP State Implementation Plan

SLAMS State and Local Air Monitoring Stations

SO2 Sulfur dioxide

U.S. EPA United States Environmental Protection Agency

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80 Annual Monitoring Network Report for Twenty-three Districts in California