Annual report / Arizona Department of Environmental Quality

              Table of Contents
Acknowledgments
List of Tables
List of Figures
Introduction
Part I - Ambient Air Quality Monitoring Networks
Criteria Pollutant Monitoring Networks
Visibility Monitoring Networks in National Parks and Wilderness Areas
Urban Haze Networks
Photochemical Assessment Monitoring Services (PAMS) Monitoring
Annual Ambient Air Monitoring Network Review
Monitoring Methods
Part II - Monitoring Data
Section A - Criteria Pollutants - 1999 Data
Carbon Monoxide
Lead
Nitrogen Dioxide
Sulfur Dioxide
Ozone
Particulate Matter Smaller than 10 Microns (PM10) and Smaller than 2.5
Microns (PM2.5)
Section B - Criteria Pollutants - Compliance
Carbon Monoxide
Lead
Nitrogen Dioxide
Sulfur Dioxide
Ozone
Particulate Matter - PM10
Particulate Matter - PM2.5
Section C - Visibility Data
Class I and Wilderness Areas
Urban Haze
Part III - Special Projects
Introduction
Douglas/Agua Prieta
Greenwood
Class I Visibility Program Update
PAMS Program Implementation
Part IV - Trends
Introduction
Carbon Monoxide
Ozone
Particulates
Visibility
Conclusions
Supplement
Site Index
Maps
List of Tables
Table Page
1 Monitoring Objectives for Air Quality Monitoring Sites
2 Measurement Scales for Air Quality Monitoring Sites
3 Monitoring Networks Operating in Arizona
4 PAMS Installation Time Line
5 1999 Carbon Monoxide Data
6 1999 Nitrogen Dioxide Data
7 1999 Sulfur Dioxide Data
8 1999 Ozone Data, 1-Hour Averages
9 1999 Ozone Data, 8-Hour Averages
10 1999 PM10 Data
11 1999 PM2.5 Data
12 1998-1999 1-Hour Carbon Monoxide Compliance
13 1998-1999 8-Hour Carbon Monoxide Compliance
14 1997-1999 8-Hour Ozone Compliance
15 1997-1999 Annual Average PM10 Compliance
16 1997-1999 Maximum 24 Hour Average PM10 Compliance
17 1997-1999 Annual Average PM2.5 Compliance
18 1997-1999 24 Hour Average PM2.5 Compliance
19 Visibility In Class I Areas
20 Phoenix Metropolitan Area
21 Tucson Metropolitan Area
22 Phoenix and Tucson Urban Haze Data
23 Annual Fourth-Highest Eight-Hour Ozone Concentrations in Greater Phoenix
24 Three-Year Averages of the Annual Fourth-Highest Eight-Hour Ozone Concentration in
Phoenix and Environs
25 Annual PM2.5 Concentrations Throughout Arizona
26 Light Extinction in Phoenix and Tucson
27 Site Index
List of Figures
Figure Page
1 Eight-Hour Maximum Carbon Monoxide Concentrations at Central Phoenix (CPHX) with the
Number of Exceedances at CPHX and in the Entire Network
2 Eight-Hour Carbon Monoxide Maxima at 22nd Street and Alvernon Way in Tucson
3 Maximum One-Hour Ozone Concentrations in Phoenix Tucson, and Yuma
4 Tucson Long-Term Trends in the Fourth-Highest Eight-Hour Ozone Concentrations at Two
Sites
5 Tucson Long-Term Trends in the Fourth-Highest Eight-Hour Ozone Concentrations at Two
Additional Sites
6 Three Year Averages of the Fourth-Highest Eight-Hour Ozone Concentrations in Greater
Phoenix
7 Annual PM10 Concentrations at Four Sites in Greater Phoenix
8 Annual PM10 Concentrations at Four Additional Sites in Greater Phoenix
9 Annual PM10 Concentrations in Tucson
10 Annual PM10 Concentrations at the Higher Concentration Sites in Arizona
11 Annual PM10 Concentrations at Lower Concentration Sites at Lower Elevations
12 Annual PM10 Concentrations at Low Concentration Sites at Higher Elevations
13 Statewide Annual PM2.5 Concentrations
14 Annual PM2.5 Concentrations in Phoenix
15 Annual PM2.5 Concentrations in Tucson
16 Light Extinction Trends in Phoenix
17 Light Extinction Trends in Tucson
18 Seasonal Patterns of Hourly Light Extinction in Tucson and Phoenix: 1993-1998
Map 1 Ambient Air Monitoring Locations in Arizona by Site Operator
Map 2 Metropolitan Phoenix Ozone, Carbon Monoxide and Particulate Matter Monitoring Sites
Map 3 Metropolitan Tucson Ozone, Carbon Monoxide and Particulate Matter Monitoring Sites
Acknowledgements
Numerous agencies, companies, individuals and organizations collected the ambient
air quality monitoring data presented in this report. The Arizona Department of
Environmental Quality (ADEQ) publishes data from these various sources to provide
as complete of a picture as possible of air quality conditions throughout Arizona and
gratefully acknowledges the efforts of all involved. Generally, ambient data presented
in this report are collected, processed and reported following U.S. Environmental
Protection Agency (EPA) policies and procedures. Air quality data collected by
ADEQ staff and contract operators also receive internal and external quality control
and assurance checks, including rigorous data verification that ADEQ has, in part,
implemented. Data provided by other sources were checked by the responsible
organization but not by ADEQ.
Both private individuals and companies under contract to ADEQ provided invalu-able
field sampler operation and data processing services in support of monitoring
activities during 1999. ADEQ appreciates their efforts, which include maneuvering
on rooftops and metal towers to operate ADEQ monitoring equipment in uncom-fortable
weather conditions, or reviewing instrument performance and ambient mon-itoring
data for technical veracity. Field staff from other public agencies also operate
numerous ambient monitoring sites in Arizona, providing spatial resolution and tem-poral
coverage of air quality conditions statewide. ADEQ recognizes the efforts of
these other monitoring and reporting agencies and appreciates the opportunity to
publish their data. Several industrial facilities collect and report ambient air quality
data to ADEQ, usually to satisfy a permit requirement; their efforts are also acknowl-edged.
Finally, ADEQ staff work daily installing, calibrating, maintaining, conducting
quality control checks, collecting, processing, performing quality assurance tests and
reporting data from a wide variety of ambient air monitoring instruments. ADEQ
management wishes to thank these staff members for their dedication to maintaining
and improving the quality of our program.
Introduction
This report presents the results of air quality monitoring conducted in 1999 through-out
Arizona. These data represent more than one hundred monitoring sites, many of
which have multiple instruments measuring a variety of gaseous, particulate and visi-bility
parameters. The majority of the air quality measurements are for traditional
pollutants (ozone, particulate matter, sulfur dioxide, carbon monoxide, nitrogen diox-ide
and lead) for which EPA has established National Ambient Air Quality Stan-dards
(NAAQS). Visibility-related measurements are an increasing part of air moni-toring
activities in Arizona. In addition to the ADEQ monitoring network, Maricopa
County, Pima County and Pinal County air quality agencies also operated networks,
as did several industrial facilities. Their data are summarized in this report.
Chapter 1 of the report discusses the purpose, measurement methods, and the specif-ic
scale of geographic resolution of the various air monitoring networks in Arizona. A
new monitoring program for collecting data on ozone precursors is introduced.
Chapter 2 summarizes the monitoring data and shows the compliance status for cri-teria
pollutants. The three sections of this part are measurement of traditional crite-ria
pollutants, compliance status of the criteria pollutants and visibility characteriza-tion.
The text describes how the measurements are made and how they relate to
compliance with the NAAQS.
Chapter 3 summarizes activities from special monitoring projects. The projects that
will be presented in this section of the report are an expanding Class I visbility moni-toring
network for larger national parks and wilderness areas, an ongoing PM10 study
centered on the Greenwood monitoring site, and a new and expanding effort to
characterize ozone precursors.
Chapter 4 reports air quality trends. Concentrations of carbon monoxide, lead and
sulfur dioxide have dramatically improved since measurements began in the 1970s,
and all monitors for these pollutants have shown compliance with their health stan-dards
in recent years. Particulate matter concentrations have improved in rural and
industrial areas where controls have been implemented, while less dramatic improve-ments
have occurred in Phoenix and Tucson. Ozone concentrations have been fairly
steady in Phoenix, Tucson and Yuma and Phoenix is the only area where violations
of the ozone standard have been recorded, although concentrations have fallen sig-nificantly,
and no exceedances have been recorded since 1997. Shorter recording
periods for visibility in urban and national parks/wilderness areas make trend assess-ments
less definitive, but assessments are shown for the two urban areas.
The supplement includes tables and maps describing where and why monitoring is
conducted.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 1
The federal Clean Air Act of 1970
required EPA to assist states and locali-ties
in establishing ambient air quality
monitoring networks to characterize
human health exposure and public wel-fare
effects of criteria pollutants. The
1977 federal Clean Air Act Amend-ments
required each state to imple-ment
a visibility monitoring network to
cover specified national parks and
wilderness areas. The Phoenix and
Tucson metropolitan areas also have
year-round visibility monitoring net-works
to assess urban hazes. All of
these networks are composed of indi-vidual
monitoring sites, which are
operated to collect ambient air quality data. This helps to identify causes of air pollu-tion
and provide Arizona citizens with local air quality conditions.
Criteria Pollutant Monitoring Networks
The criteria pollutants are presently defined as sulfur dioxide (SO2), total particulate
lead (Pb), suspended particulate matter (PM), ozone (O3), nitrogen dioxide (NO2)
and carbon monoxide (CO). Pollutants are monitored with federal reference or
equivalent methods, certified by EPA. EPA redefined PM monitoring in 1987 to
measure particles less than or equal to 10 microns in aerodynamic diameter (PM10),
and again in 1997 to measure both PM10 and particles less than or equal to 2.5
microns in aerodynamic diameter (PM2.5). Networks operated to monitor the nature
and causes of visibility impairment utilize some of the same sampling methods and
are described in more detail later in this section. Ambient monitoring networks for
air quality are established to sample pollution in a variety of representative settings,
to assess the health and welfare impacts and to assist in determining air pollution
Table I.1. Monitoring Objectives for Air Quality
Monitoring Sites
1) Determine highest concentrations expected to occur
in the area covered by the network.
2) Determine representative concentrations in areas of
high population density.
3) Determine the impact on ambient pollution levels of
significant sources or source categories.
4) Determine general background concentration levels.
5) Determine the extent of regional pollutant transport
among populated areas and in support of secondary
standards.
6) Determine the welfare-related impact in more rural
and remote areas (such as visibility impairment and
vegetation effects).
Carbon
Monoxide
X
X
X
Sulfur
Dioxide
X
X
X
X
Ozone
X
X
X
X
Nitrogen
Dioxide
X
X
X
Lead
X
X
X
X
X
Particulate
Matter
X
X
X
X
X
Micro Scale
(0 to 100 meters)
Middle Scale
(~100 to 500 meters)
Neighborhood Scale
(~0.5 to 4 kilometers)
Urban Scale
(~4 to 50 kilometers)
Regional Scale
(~10 to 100s of kilometers)
Table I.2. Measurement Scales for Air Quality Monitoring Sites
Appendix I, 2 Arizona Department of Environmental Quality 2000 Annual Report
sources. These networks cover both urban and rural areas of the state. These sam-pling
networks are designed to satisfy monitoring objectives and measurement scales
defined in Tables I.1 and I.2. For each criteria pollutant, EPA specifies monitoring
objectives that define the parameters over which the health exposure and public wel-fare
are assessed, and measurement scale classifications that describe the influence of
atmospheric movement at that location.
The types and scales of monitoring sites described above are combined into net-
Table I.3. Monitoring Networks Operating in Arizona
Network Geographic Area Monitoring Measurement Pollutant(s)
Operator Monitored Objective(s) Scale(s) Covered Monitored
Covered
ADEQ Statewide 1,2,3,4,5,6 Micro, middle, SO2, Pb, O3, NO2,
neighborhood, urban, CO, PM10, PM2.5
regional
Arizona Portland Rillito 1,3 Neighborhood PM10
Cement Company
Arizona Public Joseph City 1,3 Middle PM10
Service Company
ASARCO, Inc. Hayden 1,2,3 Middle, neighborhood SO2
BHP Copper, Inc. San Manuel 1,2,3 Middle, neighborhood SO2
Cyprus Miami Miami 1,2,3 Neighborhood SO2, PM10, PM2.5
Mining Corporation
Maricopa County Phoenix urban 1,2,3,4,5,6 Micro, middle, SO2, Pb, O3, NO2,
Environmental area and Maricopa neighborhood, urban CO, PM10
Services Dept. County regional
National Park Svc. National Parks 3,4,5,6 Urban, regional SO2, O3,NO2,
and Monuments PM10, PM2.5
Phoenix Cement Clarkdale 1,3 Neighborhood PM10, PM2.5, Pb
Company
Pima County Tucson urban area 1,2,3,4,5,6 Micro, middle, SO2, O3, NO2, CO,
Dept. of Environ- and Pima County neighborhood, urban, PM10, PM2.5
mental Quality regional
Pinal County Air Pinal County and 1,2,3,4,5 Middle, neighborhood, O3, CO, PM10,
Qual. Control Dist. Phoenix urban area urban, regional PM2.5
Praxair, Inc. Kingman 1,3 Middle PM10
Salt River Project Page and St. Johns 1,3 Urban, regional NO2, O3, SO2,
PM10, PM2.5
Southern California Bullhead City, AZ 1,2,3,4 Neighborhood, urban, SO2, NO2, PM10
Edison Company and Laughlin, NV regional
Tucson Electric Tucson and 1,2,3 Middle, regional SO2, NO2, PM10,
Power Company Springerville PM2.5
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 3
works, operated by a number of government agencies
and regulated companies. These networks are com-prised
of one or more monitoring sites, whose data are
compared to the NAAQS, as well as being statistically
analyzed in a variety of ways. The agency or company
operating a monitoring network also tracks data recovery, quality control, and quality
assurance parameters for the instruments operated at their various sites. The agency
or company often also measures meteorological variables at the monitoring site.
Finally, special continuous monitoring for the optical characteristics of the atmos-phere,
and manual sampling of ozone-forming compounds and other hazardous air
pollutants is done by some of the agencies. The Maricopa, Pima and Pinal counties'
networks are operated primarily to monitor urban-related air pollution. In contrast,
the industrial networks are operated to determine the effects of their emissions on
local air quality. The National Park Service network tracks conditions in and around
national parks and monuments. The state network monitors a wide variety of pollu-tant
and atmospheric characteristics, including urban, industrial, rural and back-ground
surveillance.
Table I.3 lists the monitoring networks and their characteristics. A list of individual
sites and monitoring parameters, based on the best available information at the time
of publication is presented in Supplement A.
Visibility Monitoring Networks in National Parks and Wilderness Areas
Visibility monitoring networks track impairment in specified national parks and
wilderness areas. These parks and wilderness areas are called Class I Areas and were
designated based on an evaluation required by Congress in the 1977 federal Clean
Air Act Amendments. The evaluation, which the U.S. Forest Service (USFS) and
National Park Service (NPS) performed, reviewed the wilderness areas of parks and
national forests which were designated as wilderness before 1977, were more than
6,000 acres in size, and have visual air quality as an important resource for visitors.
Of the 156 Class I Areas designated across the nation, 12 are located in Arizona.
From the Class I Area designations EPA initiated a nationally operated monitoring
network in 1987 called the Interagency Monitoring of PROtected Visual Environ-ments
(IMPROVE) program. The original purpose of the IMPROVE network was to
characterize broad regional trends and visibility conditions using monitoring data
collected in or near Class I Areas across the United States. The IMPROVE network
was made up of approximately 30 sites at Class I areas; during 1999 and 2000 the
number of sites will increase to approximately 110, with 14 planned for Arizona.
ADEQ selected these additional monitoring sites in or near Class I areas in the state
in order to supplement the IMPROVE network. Arizona is a member of the
IMPROVE Steering Committee.
The Arizona Class I visibility network consists of a combination of visibility monitor-
Maricopa, Pima and Pinal counties’
networks are operated primarily to
monitor urban-related air pollution
Appendix I, 4 Arizona Department of Environmental Quality 2000 Annual Report
ing sites established by ADEQ and those established
by the IMPROVE committee. Monitoring is
presently conducted, or is planned to begin in the
immediate future at the following sites: Grand
Canyon National Park - Hance, Grand Canyon -
Indian Garden, Petrified Forest National Park,
Sycamore Canyon Wilderness - Camp Raymond,
Mazatzal Wilderness - Humboldt Mountain,
Mazatzal/Pine Mountain Wildernesses - Ike's Back-bone,
Sierra Ancha Wilderness - Pleasant Valley
Ranger Station, Superstition Wilderness - Tonto
National Monument, Superstition - Queen Valley,
Saguaro National Park - West Unit, Saguaro
National Park - East Unit, Chiricahua National
Monument - Entrance Station, Galiuro Wilderness
- Muleshoe Ranch and Chiricahua Wilderness -
Rucker Canyon.
Urban Haze Networks
On behalf of ADEQ, contractors conducted
detailed studies of the nature and causes of urban
hazes in the Phoenix area during the winter of
1989-90 and in the Tucson area during the winter
of 1992-93. Each of those studies recommended
long-term, year-round visibility monitoring, and
ADEQ deployed instruments starting in 1993. Visibility monitoring data from the
Tucson and Phoenix long-term urban haze networks are needed to provide policy
makers and the public with information, track short-term and long-term trends,
assess source contributions to urban haze, and better evaluate the effectiveness of air
pollution control strategies.
Because the urban haze networks conduct routine special filter sampling of PM com-position
and variation, the data from PM10 and PM2.5 samplers operated in the
urban haze networks enhance other, related air quality databases in several ways: by
maintaining a greater density of PM sampling sites, and expanding the coverage of
existing county air pollution control agency networks into perimeter areas of urban
growth; by measuring the diurnal variation and chemical composition of PM on a
year-round basis; and by obtaining comparable PM10 and PM2.5 concentration data
by standardizing the PM10 and PM2.5 instrument types used throughout the state.
The Phoenix and Tucson metropolitan area networks are similar as well as to the
scope and scale of the networks operated by ADEQ contractors in the Phoenix and
Tucson special studies. Some of these sites are existing air pollution monitoring loca-tions,
while other, new sites have been selected and installed. The networks include
PM2.5 federal reference method sampling that began operation in January 1999.
Monitoring is presently conducted, or
is planned to begin in the immediate
future at the following sites.
Grand Canyon National Park - Hance
Grand Canyon - Indian Garden
Petrified Forest National Park
Sycamore Canyon Wilderness - Camp
Raymond
Mazatzal Wilderness - Humboldt
Mountain
Mazatzal/Pine Mountain Wildernesses -
Ike's Backbone
Sierra Ancha Wilderness - Pleasant Val-ley
Ranger Station
Superstition Wilderness - Tonto Nation-al
Monument
Superstition - Queen Valley
Saguaro National Park - West Unit;
Saguaro National Park - East Unit
Chiricahua National Monument -
Entrance Station
Galiuro Wilderness - Muleshoe Ranch
Chiricahua Wilderness - Rucker Canyon
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 5
Photochemical Assessment Monitoring Station (PAMS) Monitoring
Section 182(c)(1) of the 1990 Clean Air Act Amendments (CAAA) required the
Administrator to promulgate rules for the enhanced monitoring of ozone, oxides of
nitrogen (NOx), and volatile organic compounds (VOC) to obtain more comprehen-sive
and representative data on ozone air pollution. Immediately following the prom-ulgation
of such rules, the affected states were to commence actions necessary to
adopt and implement a program to improve ambient monitoring activities and the
monitoring of emissions of NOx and VOC. Each State Implementation Plan (SIP)
for the affected areas must contain measures to implement the ambient monitoring
of such air pollutants. The subsequent revisions to Title 40, Code of Federal Regula-tions,
Part 58 (40 CFR 58) required states to establish Photochemical Assessment
Monitoring Stations (PAMS) as part of their SIP monitoring networks in ozone
nonattainment areas classified as serious, severe, or
extreme. The principal reasons for requiring the col-lection
of additional ambient air pollutant and meteo-rological
data are the lack of attainment of the
National Ambient Air Quality Standard (NAAQS)
for ozone nationwide, and the need for a more com-prehensive
air quality database for ozone and its pre-cursors.
Enhanced ozone monitoring will provide an air quality
database that will assist air pollution control agencies
in evaluating, tracking the progress of and, if neces-sary,
refining control strategies for attaining the ozone NAAQS. Ambient concentra-tions
of ozone and ozone precursors will be used to make attainment/nonattainment
decisions, aid in tracking VOC and NOx emission inventory reductions, better char-acterize
the nature and extent of the ozone problem, and prepare air quality trends.
In addition, data from the PAMS will provide an improved database for evaluating
photochemical model performance, especially for future control strategy mid-course
corrections as part of the continuing air quality management process. The data will
be particularly useful to states in ensuring the implementation of the most cost effec-tive
regulatory controls.
The PAMS network array for an area should supply measurements, which will assist
states in understanding and solving ozone nonattainment problems. EPA has deter-mined
that for the larger areas, the minimum network that will provide data sufficient
to satisfy a number of important monitoring objectives should consist of five sites:
Type 1 Site - Upwind and background characterization
These sites are established to characterize upwind background and transported ozone
and its precursor concentrations entering the area and will identify those areas that
are subjected to overwhelming incoming transport of ozone. The Type 1 Sites are
located in the predominant morning upwind direction from the local area of maxi-mum
precursor emissions and at a distance sufficient to obtain urban scale measure-
The principal reasons for requiring
the collection of additional ambient
air pollutant and meteorological
data are the lack of attainment of
the National Ambient Air Quality
Standard (NAAQS) for ozone nation-wide,
and the need for a more com-prehensive
air quality database for
ozone and its precursors.
Appendix I, 6 Arizona Department of Environmental Quality 2000 Annual Report
ments. Typically, these sites will be locat-ed
near the upwind edge of the photo-chemical
grid model domain.
Type 2a and 2b Sites: Maximum
ozone precursor emissions impact
These sites are established to monitor
the magnitude and type of precursor
emissions in the area where maximum
precursor emissions representative of the MSA/CMSA are expected to impact and
are suited for the monitoring of urban air toxic pollutants. The Type 2 Sites are
located immediately downwind (using the same morning wind direction as for locat-ing
Type 1 Sites) of the area of maximum precursor emissions and are typically
placed near the downwind boundary of the central business district (CBD) or pri-mary
area of precursor emissions mix to obtain neighborhood scale measurements.
Additionally, a second Type 2 Sites may be required depending on the size of the
area, and should be placed in the second most predominant morning wind direction.
Type 3 Site: Maximum ozone concentration
These sites are intended to monitor maximum ozone concentrations occurring
downwind from the area of maximum precursor emissions. Locations for Type 3 Sites
should be chosen so that urban scale measurements are obtained. Typically, these
sites are located 10 to 30 miles from the fringe of the urban area.
Type 4 Site: Extreme downwind monitoring
These sites are established to characterize the extreme downwind transported ozone
and its precursor concentrations exiting the area and will identify those areas that
are potentially contributing to overwhelming ozone transport into other areas. The
Type 4 Sites are located in the predominant afternoon downwind direction from the
local area of maximum precursor emissions at a distance sufficient to obtain urban
scale measurements. Typically, these sites will be located near the downwind edge of
the photochemical grid model domain.
The data collected at the PAMS sites include measurements of O3, NOx, a target list
of VOCs including several carbonyls, as well as surface and upper air meteorology.
Most PAMS sites measure 56 target hydrocarbons on either an hourly or three hour
basis during the ozone season. The Type 2 Sites also collect data on three carbonyl
compounds (formaldehyde, acetaldehyde, and acetone) every three hours during the
ozone monitoring period. Included in the monitored VOC species are ten com-pounds
classified as hazardous air pollutants (HAPs). All stations must measure O3,
NOx, and surface meteorological parameters on an hourly basis. ADEQ has installed
two PAMS monitoring sites to date; the JLG Supersite in central Phoenix (a Type 2
Site) and the Goldfield Ranch site in the far East Valley (a Type 3 Site). A time line
describing proposed installation dates of additional sites is provided in Table I.4.
The PAMS network array for an area should sup-ply
measurements, which will assist states in
understanding and solving ozone nonattainment
problems. EPA has determined that for the larg-er
areas, the minimum network that will provide
data sufficient to satisfy a number of important
monitoring objectives should consist of five sites
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 7
Annual Ambient Air Moni-toring
Network Review
ADEQ expanded the 1999
annual ambient air monitoring
network review beyond the
State and Local Air Monitoring
Stations (SLAMS) to include
all state networks. The Code of
Federal Regulations (CFR),
Title 40, Section 58.20(d),
requires states to complete and submit to EPA an annual network review.
At 40 CFR Part 58, states are required to establish air quality surveillance systems in
their SIP. The air quality surveillance systems consist of various sites designated as
SLAMS, National Air Monitoring Stations (NAMS) and Photochemical Assessment
Monitoring Stations (PAMS). In order to provide a complete review of the air moni-toring
network, ADEQ chose to include additional stations classified as Special Pur-pose
Monitoring Stations (SPM), which includes Urban Haze monitoring sites and
IMPROVE sites, ADEQ visibility stations located in or near mandatory Class I areas,
and source-oriented monitoring sites operated independently by the permittee.
The annual network review determines conformance with the requirements of 40
CFR Part 58, Appendix D (Network Design Criteria) and Appendix E (Probe and
Path Siting Criteria) for sites classified as SLAMS, NAMS, PAMS and SPM. Class I
monitoring sites are subject to specific siting and operational guidance developed by
the IMPROVE Steering Committee. Results of the annual network review are used
to determine how well the network is achieving its required air monitoring objec-tives,
how well it meets data users needs, and how it should be modified (through
termination of existing stations, relocation of stations, establishment of new stations,
monitoring of additional parameters, and/or changes to the sampling schedule) in
order to continue to meet its objectives and data needs. The main purpose of the
review is to improve the network to ensure that it provides adequate, representative,
and useful air quality data.
During 2000, ADEQ plans to develop monitoring plans for each ambient monitoring
program (e.g. NAAQS, PAMS, Urban Haze, Class I Area Visibility) that will define
specific program goals and objectives. The initial monitoring plans will utilize inven-tories
and recommendations made in the annual network review. The monitoring
plans will then go through a review every two to three years considering factors such
as data results and completeness, site representativeness, and data representative-ness.
The monitoring plan review will also tabulate network review results accumu-lated
over the prior three-year period and will recommend changes to the monitoring
plans and instrument or operating requirements.
Monitoring Methods
Table I.4. PAMS Installation Time Line
Type of Ozone Proposed Installation
PAMS Season
Type 1 2001 Palo Verde - Wintersburg Area
Type 2 1999 Supersite - 17th Ave. and Campbell, Phoenix
Type 2a 2002 Rio Salado - Rio Salado Park Area
Type 3 2000 Goldfield Ranch - Saguaro/Apache Lake Area
Type 4 2003 Tonto - Tonto National Monument
Appendix I, 8 Arizona Department of Environmental Quality 2000 Annual Report
The gaseous criteria pollutants, SO2, O3,
NO2, CO, and optical characteristics of the
atmosphere (total light extinction, light
absorption by gases, light scattering by par-ticles,
and light absorption by particles) are
monitored with continuous analyzers that
take approximately one pollutant sample
per second. These values are then averaged
on an hourly basis, and recorded to the cor-rect
number of significant digits, based on the form of the air quality standards and
the detection limits of the instrument. In most cases, the hourly data are summarized
into the appropriate multi-hour averages. Regular checks of the stability, repro-ducibility,
precision, and accuracy of these instruments are conducted by either the
agency or company network operators. Precision and accuracy of ambient data are
assessed across an entire network, using statistical tests required by EPA.
Particulate lead (Pb), PM10 and PM2.5, are usually sampled for 24 hours, from mid-night
to midnight on every sixth day. Ambient air is drawn through an inlet of a
specified design, at a known flow rate, using a calibrated timer, onto a filter that col-lects
all PM less than a diameter specified by the inlet design. Pb, PM10, and PM2.5
samples are then processed in the same manner; the filters are weighed before and
after the sample period to determine the difference in mass and then integrated with
flow rate and timer data to arrive at a mass per unit volume concentration. In the
case of Pb, the filter is then subjected to chemical analysis to determine the amount
of Pb particulate and integrated with the flow rate and timer information to calculate
the concentration. These data are then summarized into the appropriate quarterly or
annual averages. These samplers are also certified as Federal Reference or Equivalent
Methods. Regular checks of the stability, reproducibility, precision, and accuracy of
the samplers and laboratory procedures are conducted by either the agency or com-pany
network operators. Again, precision and accuracy of ambient data are assessed
across an entire network, using statistical tests required by EPA.
Visibility monitoring methods are generally divided into three groups: optical, scene,
and aerosol (PM). Monitoring of visibility requires qualitative and quantitative infor-mation
about the causes of haze (what is in the air, e.g., the formation, transport and
deposition of pollutants), and the nature of haze (what are the optical effects of
those pollutants to the observer). Optical monitoring is discussed above. Scene con-ditions
of visual air quality associated with hazes are recorded with a color video
camera, which utilizes a super-VHS format and is programmed to advance at the rate
of one frame every four minutes during daylight hours. The video recording system is
set to start just before sunrise, and to stop just after sunset, for each day. Scene infor-mation
can also be obtained from 35 millimeter slides, taken at the same times each
day, to establish baseline conditions, and track variation in haze.
In monitoring visibility it is also essential to collect and analyze particulate samples,
to define and understand the chemistry of aerosols present before, during, and after
The gaseous criteria pollutants, SO2, O3,
NO2, CO, and optical characteristics of the
atmosphere (total light extinction, light absorp-tion
by gases, light scattering by particles, and
light absorption by particles) are monitored
with continuous analyzers that take approxi-mately
one pollutant sample per second.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 9
haze events. The chemical speciation data can be used to determine the contribu-tions
of each source category to the observed optical haze data. From these filter
data, the chemical components are used to calculate light extinction for the filter
sample period and compared with continuous measurements as a check. Finally, the
samplers used in the urban haze networks also monitor compliance with PM10 and
PM2.5 air quality standards, and provide information on the categorical source con-tributions
to observed PM10 and PM2.5 concentrations. Sampling frequency for PM
in the urban networks is generally every sixth day, and every third day in the ADEQ
and IMPROVE Class I Area networks. Sampling every day at all monitoring sites is
cost prohibitive and very personnel intensive with current particulate sampling tech-nologies.
Finally, to more fully understand the causes of
hazes often associated with certain atmospheric
conditions, it is necessary to monitor certain
meteorological parameters. For these reasons,
each network includes meteorological data
such as temperature, relative humidity, wind
speed and direction. Routine measurements of
upper air temperature and water vapor are not made in the Phoenix area but infor-mation
from the twice daily rawinsonde launches by the National Weather Service at
Tucson and Flagstaff as well as Las Vegas, NV and El Paso, TX are used to character-ize
the air masses over Arizona.
To more fully understand the causes of
hazes often associated with certain atmos-pheric
conditions, it is necessary to monitor
certain meteorological parameters. For
these reasons, each network includes mete-orological
data such as temperature, rela-tive
humidity, wind speed and direction.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 10
Air quality measurements in Arizona can be divided into three categories: criteria
pollutants, visibility, and photochemical monitoring. Each category is discussed
below. The EPA has set NAAQS (see Section B) for criteria air pollutants: carbon
monoxide, ozone, nitrogen dioxide, sulfur dioxide, lead, and PM10 and smaller. Addi-tional
PM monitoring includes the two subsets of PM10: coarse and PM less than 2.5
microns in size. These pollutants are monitored in
Arizona by industry, by county air pollution dis-tricts,
by Indian tribes, and by the ADEQ. Section
A presents the 1999 data measurements by crite-ria
pollutant. The data tables in this section are
organized by county; site operator information can
be found in the site index tables in the supple-ment
to this document. Data recovery informa-tion
(number of valid samples) is included in the
tables. The number of valid samples is important
for determining the representativeness of the
average data calculations. Section B describes the
compliance requirements and status for the criteria pollutants. Visibility monitoring
information is presented in Section C.
Section A − Criteria Pollutants, 1999 Data
Carbon Monoxide
Carbon monoxide, a colorless, odorless, tasteless gas that is produced in the incom-plete
combustion of fuels, has a variety of adverse health effects that arise from its
chemically binding with blood hemoglobin. Carbon monoxide successfully competes
with oxygen for binding with hemoglobin and thereby impairs oxygen transport. This
impaired transport leads to several central nervous system effects, such as the impair-ment
of time interval discrimination, changes in relative brightness thresholds,
increased reaction time, and headache, fatigue and dizziness. Carbon monoxide
exposures also contribute to or exacerbate arteriosclerotic heart disease.
In Arizona's metropolitan areas, about 75 percent of carbon monoxide emissions
come from on-road motor vehicles, 20 percent from off-road vehicles or equipment
such as construction vehicles and lawn and garden equipment, and 5 percent from
fuel combustion from commercial and residential heating. This pollutant has low
background levels, has its highest concentrations next to the busiest streets, and has
elevated neighborhood concentrations in locations that reflect emissions transported
from upwind portions of the city. Its concentrations peak in November to January,
because its emissions are highest in cold weather, automotive emissions of carbon
monoxide vary inversely with temperature, and because the surface layer of the
atmosphere is at its most stable. Hourly concentrations tend to be at their maximum
between 6 p.m. and midnight and during the morning rush hour.
Controls have reduced carbon monoxide emissions to the point where the standards
have been achieved in greater Phoenix in 1996 to 1999, in stark contrast to the first
The data tables in this section are organ-ized
by county; site operator information
can be found in the site index tables in
the supplement to this document. Data
recovery information (number of valid
samples) is included in the tables. The
number of valid samples is important for
determining the representativeness of the
average data calculations.
Appendix I, 11 Arizona Department of Environmental Quality 2000 Annual Report
half of the 1980s, when more than 100 exceedances were recorded each year. Similar
improvements have occurred in Tucson, where the last exceedance was recorded in
1984. Of these controls, equipping vehicles with catalytic converters and electronic
ignition systems were the most effective, but significant reductions can also be attrib-uted
to the Vehicle Inspection and Maintenance Program (beginning in 1976) and
oxygenated fuels (beginning in 1989).
Carbon monoxide is monitored continuously with non-dispersive infrared instruments
that are deployed in urban neighborhoods and near busy roadways or intersections. In
1999, 15 monitors were operated in greater Phoenix, four in Tucson, and one each in
Apache Junction and Casa Grande. Four monitors were operated at two sites in Dou-glas,
Arizona and two sites in Agua Prieta, Mexico as part of a year-long special study
of air quality conditions. Table I.5 presents the 1999 carbon monoxide data.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 12
Lead
Lead, a heavy metal with pronounced toxic effects, is present in the atmosphere as a
constituent of fine particles. Chronic lead poisoning attacks the blood, the brain and
nervous system, the kidney, and the reproductive system, with such effects as moder-ate
to severe brain and kidney damage, sterility, and abortions, stillbirths, and neona-tal
deaths. Low-level chronic exposure to lead manifests itself first in the inhibition
of the biosynthesis of hemoglobin, resulting in the anemia associated with chronic
lead poisoning.
Emissions of lead in Arizona come from the smelting of ore, the combustion of fossil
fuels, and, until the mid-1970s, from the use of alkyl lead compounds as anti-knock
additives in gasoline. With the phasing out of regular lead gasoline, the automotive
emissions of lead to the atmosphere have declined to near zero.
Controls to reduce lead emissions have been extremely effective, with a net 94 per-cent
reduction on a national basis from 1978 to 1987: automotive emissions were
reduced 97 percent through the elimination of lead compounds in gasoline; station-ary
source fuel combustion emissions were reduced 92 percent; and industrial
processes and solid waste disposal emissions were reduced substantially as well.
Appendix I, 13 Arizona Department of Environmental Quality 2000 Annual Report
Lead is monitored by analyzing PM10 samples collected for 24 hours, generally every
sixth day. Total Suspended Particulate (TSP) samplers are the Reference Method,
but are no longer used to obtain lead data. Lead is primarily a combustion product,
so PM10 samples capture ambient lead concentrations adequately. Of the 16 sites
where lead was determined in 1999, four are urban (Phoenix, Payson, Douglas, and
Nogales), three are located near either a smelter (Hayden) or cement plant (Clark-dale),
and nine are background sites (Petrified Forest NP, Chiricahua NM, Grand
Canyon − Hance, Grand Canyon − Indian Gardens, Tonto NM, Palo Verde, Organ
Pipe Cactus NM, and Hillside).
Quarterly lead averages are not included here but are available on request.
Nitrogen Dioxide
Nitrogen dioxide (NO2) is a reddish-brown gas that is formed by the oxidation of
nitric oxide (NO), which itself is a by-product of combustion of all fuels. At the low-est
nitrogen dioxide exposure levels at which adverse health effects have been
detected, respiratory damage has been observed: destruction of cilia, alveolar tissue
disruption, and obstruction of the respiratory bronchioles. Animal studies suggest
that nitrogen dioxide may be a causal or aggravating agent in respiratory infections.
Community exposure studies to lower ambient levels of nitrogen dioxide, however,
have demonstrated no significant links with respiratory symptoms or disease. This
pollutant is of greater concern in its reduction of visibility (it causes 5 percent of the
visibility reduction in Phoenix) and in its contributory role in the photochemical for-mation
of ozone.
Combustion emissions of nitrogen oxides are 95 percent nitric oxide and 5 percent
nitrogen dioxide. Because nitric oxide is rapidly oxidized to nitrogen dioxide, nitric
oxide emissions serve as a surrogate for nitrogen dioxide. In a recent Phoenix emis-sions
inventory, the transportation sector dominated nitric oxide emissions: 58 per-cent
of the emissions came from cars and trucks, 27 percent came from off-road vehi-cles
such as trains and diesel-powered construction vehicles, and 15 percent from
other sources, including power plants, biogenic emissions from soil, and stationary
combustion sources. Nitric oxide and nitrogen dioxide concentrations are highest near
major roadways. Nitric oxide concentrations decrease rapidly with distance from the
roadway, whereas nitrogen dioxide concentrations are more evenly distributed because
of their formation through oxidation and their subsequent transport. Concentrations
of nitrogen dioxide are highest in the late afternoon and early evening of winter, when
rush hour emissions of nitric oxide are converted to nitrogen dioxide under relatively
stable atmospheric conditions. Because nitric oxide reacts rapidly with ozone, noctur-nal
ozone concentrations in cities are often reduced to near-zero levels. This nitric
oxide scavenging of ozone does not occur in remote areas. Nocturnal ozone concen-trations
at background sites are high compared with the urban concentrations.
Nitrogen oxides emissions from motor vehicles have been reduced through retarda-tion
of spark timing, lowering the compression ratio, exhaust gas recirculation sys-
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 14
tems, and three-way catalysts. The Vehicle Inspection and Maintenance Program,
with its NOx test for light-duty gasoline vehicles 1981 and newer (in Phoenix only)
and its opacity test for diesel vehicles, has also helped. Reformulated gasolines also
decrease nitrogen oxides emissions: Federal Phase II gasoline, by 1.5 percent for
vehicular and 0.5 percent for off-road equipment; California Phase 2 gasoline, by 6.4
percent for vehicular and 7.7 percent for off road equipment.
Nitrogen dioxide is monitored continuously with chemiluminescence instruments,
which also determine nitric oxide concentrations and the sum of the two, NOx con-centrations.
These instruments are located in urban neighborhoods where the emis-sions
are dense or ozone concentrations tend to be at their maximum. Monitors are
also located near major coal fired electrical power plants. Twelve monitors were oper-ated
in Arizona in 1999: three near power plants, eight urban, and one background.
Table I.6 presents the nitrogen dioxide data collected in Arizona in 1999.
Appendix I, 15 Arizona Department of Environmental Quality 2000 Annual Report
Sulfur Dioxide
Exposure to sulfur dioxide, a colorless gas with a pungent, irritating odor at elevated
concentrations, alters the mechanical function of the upper airway, including
increasing the nasal flow resistance and decreasing the nasal mucus flow rate. short-term
exposures result in an exaggerated air flow resistance in about 10 percent of the
subjects tested, and produce acute bronchioconstriction in strenuously exercising
asthmatics.
In Arizona the principal source of sulfur dioxide emissions has been the smelting of
sulfide copper ore. Most fuels contain trace quantities of sulfur, and their combustion
releases both gaseous sulfur dioxide (SO2) and particulate sulfate (SO4
--). A recent
sulfate inventory for Phoenix has 32 percent of the emissions from point sources, 26
percent from area sources, 23 percent from off-road vehicles and equipment, and 19
percent from on-road motor vehicles. Sulfur dioxide is removed from the atmosphere
through dry deposition on plants and its conversion to sulfuric acid and eventually to
sulfate. Sulfur dioxide has extremely low background levels, with elevated concentra-tions
found downwind of large point sources. Concentrations in urban areas are low
and are homogeneously distributed, with annual averages varying from 3 to 11 μg/m3.
Major controls were installed in Arizona’s copper smelters in the 1980s, reducing sul-fur
dioxide emissions substantially. Vehicular emissions of sulfur dioxide and sulfate
have been reduced through lowering the sulfur content in diesel fuel and gasoline.
Sulfur dioxide is monitored continuously with pulsed fluorescence instruments, most
of which are clustered around copper smelters or coal fired electric power plants. In
1999, 13 reporting monitors were sited near copper smelters, two near power plants
and four in urban areas. Table I.7 presents the sulfur dioxide data collected in Ari-zona
in 1999.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 16
Ozone
Ozone, a colorless, slightly odorous gas, is both a natural component of the atmos-phere,
through its photochemical formation from natural sources of methane, carbon
monoxide, hydrocarbons, and nitrogen oxides, and an important air contaminant in
urban atmospheres. In the stratosphere, ozone blocks harmful ultraviolet radiation.
Appendix I, 17 Arizona Department of Environmental Quality 2000 Annual Report
In the urban atmosphere, its formation from anthropogenic emissions of hydrocar-bons
and nitrogen oxides leads to concentrations harmful to people, animals, plants,
and materials. Ozone causes significant physiological and pathological changes in
both animals and humans at concentrations present in many urban environments.
Short-term (one to two hours) exposures to concentrations in the range of 0.1 to 0.4
parts per million induce the following changes in lung function: increased respiratory
rates, increased pulmonary resistance, decreased tidal volumes, and changes in lung
mechanics. Symptomatic responses in exercising adults include throat dryness, chest
tightness, substernal pain, cough, wheeze, pain on deep inspiration, shortness of
breath, and headache. These symptoms also have been observed at lower concentra-tions
for longer exposures. Evidence suggests that ozone exposure makes the respira-tory
airways more susceptible to other bronchioconstrictive challenges. Animal stud-ies
suggest that ozone exposure interferes with or inhibits the immune system. Ozone
at ambient concentrations injures the stomates, which are the cells that regulate
plant respiration, resulting in flecks on the upper leaf surfaces of dichotomous plants
and the death of the tips of coniferous needles. Ozone is considered by plant scien-tists
to be the most important of all of the phytotoxic air pollutants, causing more
than 90 percent of all plant injury from air pollution on a global basis.
Ozone is formed photochemically by the reaction of volatile organic compounds and
nitrogen oxides. Volatile organic compound (VOC) emissions in greater Phoenix
come from cars and trucks (31 percent), off-road vehicles and equipment such as
lawn mowers (27 percent), small stationary sources (20 percent), biogenic emissions
from grass, shrubs, and trees (17 percent), and point sources (5 percent). Nitrogen
oxides (NOx) come from cars and trucks (58 percent), off-road vehicles such as con-struction
equipment and trains (27 percent), electric power plants (7 percent), small
stationary sources (4 percent), and biogenic emissions from soil (4 percent). Ozone
has relatively high background levels, with the daily maximum in remote areas being
about one-half to three-quarters of the daily maximum in the urban areas. Within an
urban area, the highest ozone concentrations tend to occur on the downwind edge,
although high concentrations do occur less frequently in the central city. High ozone
concentrations are a summer phenomenon, when sunlight and evaporative hydrocar-bon
emissions peak. Ozone concentrations are low to near zero at night, rise rapidly
through the morning, and peak in the afternoon.
Controls to reduce the precursors of ozone, VOC and NOx, have been carried out
successfully for years. Nitrogen oxides and exhaust VOC from vehicles have been
reduced through engine modifications and three-way catalytic converters. Evapora-tive
hydrocarbons from vehicles have been reduced through better engineered fuel
tanks and auxiliary plumbing combined with carbon absorption canisters. Additional
reductions of vehicular VOC have come through the Vehicle Inspection and Mainte-nance
Program, which tests all gasoline vehicles for hydrocarbons (Phoenix and Tuc-son),
through vapor-capturing equipment for gasoline tankers, through vapor recov-ery
systems at retail gas stations (Phoenix area only), and through reformulated gaso-line
(Maricopa County only). Stationary source hydrocarbons have been reduced
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 18
through a variety of better control equipment required by stricter regulations. Despite
these efforts, the continued growth in Arizona, combined with the high natural back-ground
ozone, will make achieving the eight-hour standard a difficult proposition.
Ozone is monitored continuously with ultraviolet absorption instruments in urban
neighborhoods for population exposure, in areas downwind of urban areas for maxi-mum
concentration monitoring, and in remote areas for background information. In
1999, 34 reporting ozone monitors were in operation; five were for background, 22
for urban neighborhoods, and 10 for maximum concentrations downwind of urban
areas. Tables I.8 and I.9 present the ozone data collected in Arizona in 1999.
Appendix I, 19 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 20
Appendix I, 21 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 22
Particulate Matter Smaller Than 10 Microns (PM10) and Smaller Than
2.5 Microns (PM2.5)
“Particulate matter” is a collective term describing very small solid or liquid particles
that vary considerably in size, geometry, chemical composition, and physical proper-ties.
Produced by both natural processes (pollen, wind erosion) and human activity
(soot, fly ash, dust from paved and unpaved roads), particulates contribute to visibili-ty
reduction, pose a threat to public health, and cause economic damage through
soiling. Some fine particulates (PM2.5) are formed by the condensation of vapors or
by their subsequent growth through coagulation or agglomeration. Others are emit-ted
directly from the sources, either combustion or from mechanical grinding of soils.
Coarse particulates (2.5 to 10 microns) are formed through mechanical processes
such as the grinding of matter and the atomization of liquids. Fine particulates can
also be classified as primary (produced within and emitted from a source with little
subsequent change) or secondary (formed in the atmosphere from gaseous emis-sions).
Secondary particulate nitrates and sulfates, for example, form in the atmos-phere
from the oxidation of sulfur dioxide and nitric oxide gases. Most atmospheric
carbon, on the other hand, is primary, having been emitted directly from combustion
sources, although some of the organic carbon in the aerosol is secondary, having
been formed by the complex photochemistry of gaseous volatile organic compounds.
The health effects of particulates depend on their size, shape, and chemical composi-tion.
Particles larger than 10 microns are deposited in the upper respiratory tract.
Particles from 2.5 to 10 microns are inhalable and are deposited in the upper parts of
the respiratory system. Particles smaller than 2.5 microns are respirable and enter the
pulmonary tissues to be deposited there. Particles in the size range of 0.1 to 2.5
microns are most efficiently deposited in the alveoli, where their effective toxicity is
greater than larger particles because of the higher relative content of toxic heavy
metals, sulfates, and nitrates. Epidemiological studies have shown causal relation-ships
between particulates and excess mortality, aggravation of bronchitis and small
reversible changes in pulmonary function in children. Acidic aerosols have been
linked to the inability of the upper respiratory tract and pulmonary system to remove
harmful particles.
The Arizona Comparative Environmental Risk Project, a multi disciplinary investiga-tion
into human exposure to all environmental risks, which was completed in 1995,
Appendix I, 23 Arizona Department of Environmental Quality 2000 Annual Report
ranked outdoor air quality in general and PM in particular, as the highest environmen-tal
risk in the state. Annual premature deaths from exposure to PM10 concentrations
in Arizona were estimated at 963, including 667 in Maricopa County and 88 in Tuc-son.
Increased percentages of hospital admissions for respiratory disease (1 to 4 per-cent,
depending on the city), of asthma episodes (5 to 14 percent), of lower respiratory
symptoms (5 to 15 percent), and of coughs (2 to 6 percent) were attributed to the pre-vailing
(1991) annual PM10 concentrations. Chronically high particulates concentra-tions
in the ambient air continue to pose a serious health threat to many Arizonans.
Coarse particulate emissions are mostly geological and are dominated by dusts from
three activities: reentraining dust from paved roads, driving on unpaved roads, and
earthmoving associated with construction. Soil dust from these sources and others
contribute more than 70 percent of the coarse particulates in Phoenix. On days with
winds in excess of 15 miles per hour, wind erosion of soil contributes to this loading.
With a more diverse chemical composition, fine particulates (PM2.5) emissions are
more evenly distributed among a larger number of sources. At the Phoenix JLG
Supersite, receptor modeling indicates gasoline and diesel engine exhaust account for
more than two-thirds of the PM2.5 emissions. Soil dust contributes another 10.5 per-cent.
In other urban and rural areas, this mixture of sources will vary: agricultural
and mining areas, for example, will be more heavily influenced by emissions from
these activities.
PM2.5 concentrations tend to be at their highest in the central portions of urban
areas, diminishing to background levels at the urban fringe. In contrast, PM10 con-centrations
are not smoothly spatially distributed, because each monitoring site is
strongly influenced by the degree of localized emissions of coarse particulates. Back-ground
concentrations of PM10 are about 40 percent of the urban maxima (20 μg/m3
for an annual average background versus about 50 μg/m3 for the urban maximum).
Background concentrations of PM2.5 are about 5 μg/m3, in contrast to the urban
maxima of 12 to 15 μg/m3. Concentrations of both size ranges of particulates tend to
be higher in the late fall and winter, when atmospheric dispersion is at a seasonal low.
PM10 maximum concentrations can occur in any season, provided nearby sources of
coarse particulates are present or when strong and gusty winds suspend soil disturbed
by human activities. Hourly concentrations of particulates tend to peak during those
hours of the poorest dispersion, which occur from sunset to mid-morning.
Controls to reduce particulates have been in place for decades, beginning with an
ordinance that required watering to reduce dust from construction in Pima County
in the 1960s. Maricopa County's umbrella dust abatement rule, Rule 310, has gone
through many additions through the years, and now is regulating construction dust,
track-out dust from construction sites, and dust from unpaved parking lots. Efforts to
reduce dust resuspended from paved roads have concentrated on eliminating track-out
from construction sites, curbing and stabilizing road shoulders, and investigating
more efficient street sweepers. Secondary fine particulates have been reduced by
vehicular emission controls that have reduced their precursor gases. Reducing
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 24
gaseous hydrocarbon emissions has led to a significant reduction in the primary car-bon
emitted in motor vehicle exhaust. In Maricopa County, the Governor's Agricul-tural
Best Management Practices Advisory Committee is developing best manage-ment
practices for agricultural activities intended to reduce particulate emissions
from tilling, harvesting, and other activities. In a recent PM10 control plan, the
Maricopa Association of Governments received commitments to implement 77 new
measures, including better enforcement of the dust rules, agricultural best manage-ment
practices, diesel engine replacement and retirement programs, cleaner burning
fireplaces, and stricter standards for utility equipment.
Particulates are monitored by pulling ambient air through a filter, generally for 24
hours every sixth day, weighing the filter before and after, and measuring the volume
of air sampled. Prior to 1999 the concentrations were calculated using this informa-tion
and a uniform temperature and pressure. For 1999, EPA required concentrations
to be calculated using local (at the monitor) temperature and pressures. For 2000,
the concentrations will revert to the standard temperature and pressure calculation.
The monitoring instruments are fitted with different aerodynamic devices to segre-gate
different particle size fractions. Particulates can also be monitored continuously,
with a Tapered Element Oscillating Microbalance (TEOM) instrument.
The 1999 PM10 data reported below in Table I.10 represent 85 monitors throughout
Arizona. To support special border studies, three ADEQ monitors were located in
Mexico, two in Agua Prieta and one in Nogales, Sonora. Please note that TEOM
data are not included in this table.
The EPA began a nationwide program to measure Particulate Matter 2.5 microns
and smaller (PM2.5) using Federal Reference Method (FRM) monitors made to EPA
specifications in anticipation of the acceptance of a new standard for fine particu-lates.
The fine particulate portion of the PM10 measurement made by dichot moni-tors
has been measured for many years in Arizona and has served as an approxima-tion
for the PM2.5 measurement. Table I.11 lists both Dichot Fine and FRM meas-urements
for 1999.
Appendix I, 25 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 26
Appendix I, 27 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 28
Appendix I, 29 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 30
Appendix I, 31 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 32
Section B − Criteria Pollutants, Compliance
Carbon Monoxide
There are two NAAQS for carbon monoxide: an eight-hour standard (most critical
for compliance) and a one-hour standard. The eight-hour standard is 9 ppm; the
one-hour standard is 35 ppm. According to the Code of Federal Regulations, compli-ance
for both standards is determined by having no more than one exceedance per
calendar year. Attainment of the standard is determined by EPA at all sites in the
nonattainment (or monitoring) area by evaluating two
calendar years of data from each site. The highest of the
second-highest values for the two-year period must not
exceed the standard of 9 ppm (greater than or equal to
9.5 ppm to adjust for rounding) for the eight-hour stan-dard
or 35 ppm (greater than or equal to 35.5 ppm) for
the one hour standard.
No exceedances of the one-hour standard were recorded
in 1999. The eight-hour standard was exceeded on Nov.
30, 1999 at the ADEQ Grand Avenue monitor in
Phoenix, but this was the only exceedance at this moni-tor
during the 1998-1999 period. Therefore, no violation of the standard occurred
and the monitor is in compliance. The data are presented in Tables I.12 and I.13.
Values in bold exceed the standard.
1999 one-hour CO NAAQS
compliance values by county
Exceedances Violations
Maricopa 0 0
Pima 0 0
Pinal 0 0
21 of 21 monitors in compliance
Appendix I, 33 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 34
Lead
In 1999, the NAAQS for lead, 1.5 micrograms per cubic meter (μg/m3) averaged for
a calendar quarter, was not exceeded at any Arizona monitor.
Nitrogen Dioxide
The NAAQS for nitrogen dioxide is 0.053 parts per million for an annual average.
The standard is attained when the annual arithmetic mean concentration in a calen-
Appendix I, 35 Arizona Department of Environmental Quality 2000 Annual Report
dar year is less than or equal to 0.053 ppm. To demon-strate
attainment, the annual mean must be based upon
hourly data that are at least 75 percent complete. The
1999 nitrogen dioxide annual averages near Arizona
power plants ranged from 2 percent to 19 percent of the
standard; in the urban areas, 22 percent to 77 percent.
All Arizona sites were in compliance with the NAAQS.
Refer to Table I.6 for the 1999 averages.
Sulfur Dioxide
There are three NAAQS for sulfur dioxide, two primary
(annual average and 24-hour block average) and one
secondary (three-hour block average). The annual aver-age
standard is 80 μg/m3 (approximately 0.03 ppm) and
the maximum 24-hour block average standard is 365
μg/m3 (approximately 0.14 ppm). To demonstrate attain-ment,
neither standard can be exceeded in a calendar
year. Also, the averages must be based upon hourly data
that are 75 percent complete. A 24-hour block average is
considered valid if at least 75 percent of the hourly aver-ages
for the 24-hour period are available. The 24-hour
averages are determined from successive non-overlap-ping
24-hour blocks that begin at midnight each day.
The secondary three-hour standard is 1300 μg/m3
(approximately 0.50 ppm) and is not to be exceeded
more than once per calendar year. The three-hour aver-ages
are determined from successive non-overlapping
three-hour blocks starting at midnight each calendar day.
In Arizona, the maximum concentration sites, all near
copper smelters, comply with these standards; the con-centrations
being no higher than 65 percent of the
three-hour, 90 percent of the 24-hour, and 55 percent of
the annual average standards. Sites near power plants
are close to background levels, with annual averages
from less than 1 to 8 μg/m3. Refer to Table I.7 for the
1999 averages.
Ozone
The NAAQS include a standard for one-hour ozone and a standard for
eight-hour ozone. The one-hour standard is 0.12 ppm. Compliance with
this standard is attained when the expected number of days per calendar
year with maximum hourly average concentrations above 0.12 ppm
(0.124 ppm for rounding ) is equal to or less than one. A daily
exceedance is defined as any day having one or more hourly averages
equal to or greater than 0.125 ppm. Hourly averages for at least 75 per-
1999 lead quarterly average NAAQS
compliance values by county
Exceedances Violations
Apache 0 0
Cochise 0 0
Coconino 0 0
Gila 0 0
Maricopa 0 0
Pima 0 0
Pinal 0 0
Santa Cruz 0 0
Yavapai 0 0
16 of 16 monitors in compliance
1999 NO2 quarterly average
NAAQS compliance values by county
Exceedances Violations
Apache 0 0
Maricopa 0 0
Mohave 0 0
Pima 0 0
13 of 13 monitors in compliance
1999 SO2 annual NAAQS
compliance values by county
Exceedances Violations
Apache 0 0
Gila 0 0
Maricopa 0 0
Mohave 0 0
Pima 0 0
Pinal 0 0
20 of 20 monitors in compliance
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 36
cent of the hours sam-pled
(18 to 24 hours per
day) must be present.
The most recent three
calendar years of daily
averages are used to
determine if the annual
standard is met.
Arizona had no
exceedances of the one-hour
standard 1999.
The last exceedance of
the one-hour standard
occurred in 1996 in
Phoenix.
The eight-hour ozone
standard proposed by
EPA was developed in
response to human
exposure studies that
showed adverse health
effects occur at lower
ozone concentrations
extending over several
hours. The new ozone
standard was promulgat-ed
in 1997, but in a May
14, 1999 decision by the
U. S. Court of Appeals for the District of Columbia, it was remanded to
EPA for further consideration. However, monitoring agencies have been
recording the eight-hour averages to gather information on occurrence
and ability to comply with an eight-hour standard.
1999 SO2 24-hour NAAQS
compliance values by county
Exceedances Violations
Apache 0 0
Gila 0 0
Maricopa 0 0
Mohave 0 0
Pima 0 0
Pinal 0 0
20 of 20 monitors in compliance
1999 SO2 three-hour NAAQS
compliance values by county
Exceedances Violations
Apache 0 0
Gila 0 0
Maricopa 0 0
Mohave 0 0
Pima 0 0
Pinal 0 0
20 of 20 monitors in compliance
1997-1999 one-hour ozone compliance values by county
# of Daily Exceedances Sites in Violation
1997 1998 1999
Cochise 0 0 0 0
Coconino 0 0 0 0
Gila 0 0 0 0
Maricopa 0 0 0 0
Pima 0 0 0 0
Pinal 0 0 0 0
Yavapai 0 0 0 0
Yuma 0 0 0 0
35 of 35 monitors in compliance for 1997-1999
1997-1999 eight-hour ozone compliance values by county
# of Eight-Hour Exceedances Sites in Violation
1997 1998 1999
Cochise 0 0 0 0
Coconino 0 0 0 0
Gila 0 0 0 0
Maricopa 42 84 62 6
Pima 0 0 0 0
Pinal 0 0 0 0
Yavapai 0 0 0 0
Yuma 0 0 0 0
27 of 34 monitors in compliance for 1997-1999
Appendix I, 37 Arizona Department of Environmental Quality 2000 Annual Report
The eight-hour ozone standard is 0.08 ppm (0.084 for rounding) for a daily maxi-mum
eight-hour average. This standard is met when the average of the annual
fourth-highest daily maximum eight-hour average ozone concentration is less than or
equal to 0.08 ppm. The most recent three calendar years are used to assess compli-ance
with the standard. Values in bold in Table I.14 exceed the standard.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 38
Particulate Matter − PM10
The NAAQS for PM10 are 50 μg/m3 for the annual arithmetic mean concentration
and 150 μg/m3 for the 24-hour average concentration. The annual standard is met
when the three year average of the annual means is less than or equal to 50 μg/m3.
The annual average is determined by calculating quarterly (three month) averages of
the samples collected during that quarter; a minimum of 75 percent of the samples
must be present to produce a valid annual average. The four quarterly averages are
then used to produce the annual average. Compliance with the 24-hour PM10 stan-dard
is attained when the expected exceedance rate of occurrence of samples greater
than or equal to 150 μg/m3 is one or less per year measured over three years. The
same requirements of 75 percent completeness and three consecutive years of data
apply. Tables I.15 and I.16 present the 1997-1999 data.
Appendix I, 39 Arizona Department of Environmental Quality 2000 Annual Report
1997-1999 PM10 annual average
compliance values by county
# of Exceedances Sites in
1997 1998 1999 Violation
Apache 0 0 0 0
Cochise 0 0 0 0
Coconino 0 0 0 0
Gila 0 0 0 0
Maricopa 3 2 3 3
Mohave 0 0 0 0
Navajo 0 0 0 0
Pima 0 0 0 0
Pinal 1 1 1 1
Santa Cruz 0 0 0 0
Yavapai 0 0 0 0
Yuma 0 0 0 0
62 of 66 monitors in compliance for 1997-1999
1997-1999 PM10 maximum 24-hour
compliance values by county
Eight-Hour Exceedances Sites in
1997 1998 1999 Violation
Apache 0 0 0 0
Cochise 0 0 0 0
Coconino 0 0 0 0
Gila 0 0 0 0
Maricopa 17 0 1 0
Mohave 0 0 0 0
Navajo 0 0 0 0
Pima 0 0 0 0
Pinal 0 1 3 1
Santa Cruz 0 1 2 0
Yavapai 0 0 0 0
Yuma 0 0 0 0
72 of 73 monitors in compliance for 1997-1999
County and City or Site Annual Averages Three-Year
Average
1997 1998 1999
Coconino
Flagstaff - ADOT 15 12 16 a 14 a
Flagstaff -Middle School 15 13 14 14
Grand Canyon - Hance N/A 10 13 a N/A
Grand Canyon - Indian Gardens 14 10 10 a 11 a
Sedona 11 10 N/A N/A
Gila
Hayden - Old Jail 36 28 35 33
Miami - Golf Course 27 23 22 24
Miami - Ridgeline 14 11 13 13
Payson 25 24 21 a 23
Tonto NM 12 11 13 a 12 a
Graham
Safford 29 27 N/A N/A
Maricopa
Central Phoenix 44 N/A 43.6 a N/A
Chandler 61 45 60 55
Estrella 35 25 34 31
Gilbert 49 42 45 45
Glendale 38 29 36 34
Higley 64 50 61 58
Maryvale 49 36 45 43
Mesa 43 29 35 36
North Phoenix 38 29 35 34
Palo Verde 20 19 22 20
County and City or Site Annual Averages Three-Year
Average
1997 1998 1999
Phoenix - JLG Supersite 39 31 34 35
Phoenix - Greenwood, ADEQ N/A 43 54 N/A
Phoenix - Greenwood, MCESD 61 50 56 56
Phoenix - ASU West 34 25 31 30
South Scottsdale 41 34 40 38
Tempe 36 31 35 34
West Chandler 45 34 48 42
West Phoenix 51 39 51 47
Mohave
Bullhead City - Alonas Way 21 22 30 24
Bullhead City - Hwy. 95 N/A 11 13 N/A
Fort Mohave 15 12 12 a 13
Kingman - Praxair 12 12 16 13
Navajo
Joseph City - Third and Tanner 15 11 17 14
Show Low 16 11 16 a 14
Pima
Ajo 20 21 21 21
Corona de Tucson 15 14 18 16
Green Valley 16 14 18 16
Organ Pipe Cactus National Monument 10 8 10 a 9
Rillito - ADEQ 26 29 35 a 30
Rillito - APCC 40 30 31 34
South Tucson 33 36 48 39
Tucson - Broadway and Swan 28 24 32 28
County and City or Site Annual Averages Three-Year
Average
1997 1998 1999
Tucson - Central U of A, ADEQ (teflon) 27 23 26 25
Tucson - Craycroft, ADEQ 26 21 26 24
Tucson - Downtown (closed May 27, 1999) 29 29 35 31
Tucson - Orange Grove 31 24 46 34
Tucson - Prince Road 34 33 44 37
Tucson - Santa Clara 27 25 34 29
Tucson - Tangerine 15 12 18 15
Pinal
Apache Junction - South County Courthouse 25 26 28 26
Apache Junction - North County Courthouse 25 25 26 25
Casa Grande 32 31 35 33
Casa Grande - County Fairgrounds, Eleven Mile
Corner
52 52 71 58
Coolidge 39 37 40 39
Eloy 38 44 46 43
Mammoth 22 22 23 22
Pinal Air Park - Marana 26 27 30 28
Stanfield 42 41 57 47
Santa Cruz
Nogales Post Office 31 38 54 a 41
Yavapai
Clarkdale - SE of CTI Flyash Silo (#1) 24 25 28 26
Clarkdale - NW of Cement Plant (#2) 24 19 23 22
Clarkdale - ADEQ 15 15 15 15
Hillside 12 12 8 a 11
Nelson 14 11 13 13
County and City or Site Annual Averages Three-Year
Average
1997 1998 1999
Yuma
Yuma Juvenile Center 36 39 37 37
a Annual average based on less than 75 percent data recovery per quarter.
N/A - Data not available or annual average not able to be calculated due to insufficient data.
Table I.16. 1997-1999 Maximum 24-Hour Average PM10 Compliance (in mg/m3)
Values in bold exceed the standard.
County and City or Site 1997 1998 1999 Expected
Exceedance
Max Rate
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Apache
Petrified Forest NP 43 0 17 0 71 a 0 0
St. Johns - Mesa Parada 18 0 17 0 44 a 0 Sampling
discontinued
St. Johns - Carrizo Draw 18 0 36 0 56 a 0 May 1999
Springerville - Coyote Hills 22 0 25 0 25 0 0
Springerville - Coalyard 34 0 26 0 49 0 0
Cochise
Chiricahua NM 35 0 35 0 28 a 0 0
Douglas - High School/Red Cross 55 0 105 0 83 a 0 0
Naco 113 0 116 0 85 0 0
Paul Spur 77 0 82 0 78 0 0
Coconino
Flagstaff - ADOT 40 0 33 0 62 a 0 0
Flagstaff - Middle School 32 0 30 0 35 0 0
Grand Canyon - Hopi Pt./Hance 31 0 30 0 25 a 0 0
Grand Canyon - Indian Gardens 82 0 31 0 22 a 0 0
County and City or Site 1997 1998 1999 Expected
Exceedance
Max Rate
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Sedona 24 0 54 0 17 0 0
Gila
Hayden - Old Jail, ADEQ 158 1 78 0 84 0 < 1.0
Miami - Golf Course 67 0 51 0 43 0 0
Miami - Ridgeline 33 0 27 0 34 0 0
Payson 81 0 69 0 47 a 0 0
Tonto NM 42 0 31 0 36 a 0 0
Graham
Safford 95 0 98 0 125 a 0 0
Maricopa
ASU West 164 1 55 0 55 0 < 1.0
Central Phoenix 108 0 70 0 85 a 0 0
Chandler 221 1 136 0 110 0 < 1.0
Estrella 179 1 56 0 80 0 < 1.0
Gilbert 170 1 133 0 90 0 < 1.0
Glendale 170 1 61 0 77 0 < 1.0
Higley 288 2 135 0 208 1 1.0
Maryvale 345 2 92 0 104 0 < 1.0
Mesa 129 0 64 0 80 0 0
North Phoenix 152 1 67 0 70 0 < 1.0
Palo Verde 124 0 47 0 83 0 0
Phoenix - JLG Super Site 131 1 69 0 78 0 < 1.0
Phoenix - Greenwood, ADEQ 148 0 106 0 111 0 0
Phoenix - Greenwood, MCESD 220 1 121 0 117 0 < 1.0
County and City or Site 1997 1998 1999 Expected
Exceedance
Max Rate
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
South Phoenix 160 1 77 0 67 1 1.0
South Scottsdale 154 1 81 0 87 0 < 1.0
Tempe 90 0 70 0 82 0 0
West Chandler 194 2 78 0 104 0 < 1.0
West Phoenix 224 1 107 0 111 0 < 1.0
Mohave
Bullhead City - Alonas Way 51 0 76 0 122 0 0
Bullhead City - Hwy. 95 30 0 27 0 26 0 0
Fort Mohave 68 0 39 0 30 a 0 0
Kingman - Praxair 34 0 70 0 46 0 0
Navajo
Joseph City - Third and Tanner 35 0 26 0 57 0 0
Show Low 127 0 27 0 38 a 0 0
Pima
Ajo 65 0 65 0 41 0 0
Corona de Tucson - PDEQ 34 0 41 0 51 0 0
Green Valley - PDEQ 42 0 32 0 38 0 0
Organ Pipe Cactus National
Monument
75 0 22 0 18 a 0 0
Rillito - ADEQ 129 0 74 0 98 a 0 0
Rillito - APCC 77 0 79 0 123 0 0
South Tucson - PDEQ 72 0 79 0 214 2 x 0
Tucson - Broadway and Swan 58 0 49 0 89 0 0
Tucson - Central U of A, ADEQ
(teflon)
58 0 48 0 54 0 0
County and City or Site 1997 1998 1999 Expected
Exceedance
Max Rate
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Tucson - Craycroft, ADEQ 63 0 51 0 55 0 0
Tucson - Downtown 72 0 90 0 129 0 Closed May
27, 1999
Tucson - Orange Grove, PDEQ 68 0 44 0 235 4 x 0
Tucson - Prince Road 62 0 83 0 118 0 0
Tucson - Santa Clara 64 0 50 0 97 0 0
Tucson - Tangerine 40 0 29 0 41 0 0
Pinal
Apache Junction - South County
Courthouse
81 0 63 0 64 0 0
Apache Junction - North County
Courthouse
81 0 61 0 64 0 0
Casa Grande 76 0 74 0 64 0 0
Casa Grande - County
Fairgrounds, Eleven Mile Corner
140 0 162 1 368 3 2
Coolidge 102 0 143 0 84 0 0
Eloy 82 0 110 0 142 0 0
Mammoth 46 0 49 0 50 0 0
Pinal Air Park - Marana 65 0 67 0 60 0 0
Stanfield 135 0 113 0 107 0 0
Santa Cruz
Nogales Post Office 126 0 155 1 169a 2 1.0
Yavapai
Clarkdale - SE of CTI Flyash Silo
(#1)
50 0 51 0 53 0 0
County and City or Site 1997 1998 1999 Expected
Exceedance
Max Rate
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Max
24-
hour
No.
of
Exc.
Clarkdale - NW of Cement Plant
(#2)
33 0 82 0 48 0 0
Clarkdale - ADEQ 63 0 26 0 30 0 0
Hillside 85 0 20 0 22 a 0 0
Nelson 53 0 53 0 32 0 0
Yuma
Yuma Juvenile Center 108 0 109 0 102 0 0
a Less than 75 percent data recovery per quarter.
x Exceedances at the Orange Grove and South Tucson sites in Pima County are flagged as due to natural
events and are excluded from the compliance calculation.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 48
Particulate Matter − PM2.5
The proposed NAAQS for partic-ulate
matter 2.5 microns and
smaller in diameter (PM2.5) are
under review due to the District of
Columbia Court of Appeals May
1999 decision. However, these
standards will be used to assess the
compliance of the monitors oper-ating
in Arizona. The standards
are 15.0 micrograms per cubic
meter (μg/m3) for the annual
arithmetic mean concentration
and 65 μg/m3 for the 24-hour
average concentrations.
The annual PM2.5 standard is met
when the three-year average of
annual means is less than or equal
to 15.0 μg/m3. This three-year
average is determined by calculat-ing
the quarterly averages for each
year (with 75 percent data recov-ery
in each quarter) to determine
the calendar year average and then
averaging the three years together.
The 24-hour standard is met when
the three-year average of the 98th
percentile values is less than or
equal to 65 μg/m3. There must
also be 75 percent data complete-ness
for each year.
Please note that the data in the Table I.17 are from dichot monitors only since the
Federal Reference Method program to monitor PM2.5 did not begin until 1999. Val-ues
in bold exceed the standard.
1997-1999 PM2.5 annual average compliance values by
county
# of Exceedances Sites in Violation
1997 1998 1999
Cochise 0 0 0 0
Coconino 0 0 0 0
Gila 0 0 0 0
Maricopa 0 0 1 0
Mohave 0 0 0 0
Pima 0 0 0 0
Santa Cruz 0 0 1 0
Yavapai 0 0 0 0
Yuma 0 0 0 0
24 of 24 monitors in compliance for 1997-1999
1997-1999 PM2.5 24-hour average compliance values
by county
# of Exceedances Sites in Violation
1997 1998 1999
Cochise 0 0 0 0
Coconino 0 0 0 0
Gila 0 0 0 0
Maricopa 0 0 0 0
Mohave 0 0 0 0
Pima 0 0 0 0
Santa Cruz 0 0 1 0
Yavapai 0 0 0 0
Yuma 0 0 0 0
24 of 24 monitors in compliance for 1997-1999
Appendix I, 49 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 50
Appendix I, 51 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 52
Section C − Visibility Data
Visibility monitoring consists of three types: aerosol, optical and scene. Aerosol
measurements are described elsewhere in this report; however, those measurements
are used differently in characterizing visibility impairment. The chemical species that
comprise a particulate sample have different extinction efficiencies. Extinction effi-ciency
is the extent to which a particle will either scatter or absorb light, thus block-ing
its path to one’s eye. The overall impact of particles can be estimated by sum-ming
the effect of all the component species. This method is the primary approach
used in the draft national regional haze rule for estimating present visibility and
charting trends for future plan reviews.
Optical measurements can be taken in several ways whose differences are related to
characterizing different optical phenomena. For example, the nephelometer, an
instrument used considerably by ADEQ, measures light scattering by particles. On
the other hand, the aetholometer characterizes how much light is absorbed by parti-cles
in the atmosphere. Finally, a transmissometer measures the composite of these
optical processes. Data collected by each of these instruments can be represented by
several different measurement units, including the deciview, inverse megameters, and
visual range. The deciview is similar to the decibel and represents in a linear fashion
how the perception of visibility changes. The inverse megameter is a representation
of the ratio between how much light is not received by a sensor compared to the
amount of light that leaves a source. Finally, visual range, the most familiar represen-tation,
quantifies how far one can see. One of the longest records of visibility condi-tions
is human observation of visual range at airports.
Scene information comes primarily from pictures, which provide insight into the
structure and extent of haze in the atmosphere. Photography is also used to establish
a baseline clean scene and estimate how much the view is obscured in other pictures.
Please refer to Chapter 1 of this report for more information on visibility monitoring.
Appendix I, 53 Arizona Department of Environmental Quality 2000 Annual Report
Class I and Wilderness Areas
In anticipation of the regional haze rule, ADEQ undertook development of a visibili-ty
monitoring program directed at Class I areas in partnership with Arizona's federal
land managers. The aim is to collect data at all of Arizona's Class I Areas. Based on
the regional haze rule, five years of data will be needed. Since the IMPROVE pro-gram
consists only of aerosol sampling, ADEQ will jointly operate sites by installing
nephelometers that measure light scattering. Since IMPROVE aerosol samplers will
only operate every three days and represent 24-hour averages, making continuous
measurements provides insight into variation in visibility impairment with time,
along with advancing the understanding of the relationship between particles and
light scattering.
Table I.19 summarizes the 1998 and 1999 nephelometer data from locations in or
near Arizona Class I Areas. The data are summarized into three categories for all
hours: the average visibility of the dirtiest 20 percent, the mean visibility, and the
average visibility of the cleanest 20 percent.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 54
Urban Haze
In addition to the 24-hour PM10 samples collected for regulatory purposes that can
also be used in the assessment of urban haze (shown earlier), ADEQ also has collect-ed
six hour samples of PM10 and PM2.5. The six-hour samples were for the morning
hours (5 a.m. to 11 a.m.) and were collected in the Phoenix and Tucson metropoli-tan
areas. The 1999 morning hours’ PM10 and PM2.5 observations are summarized in
Tables I.20 and I.21.
Along with the PM sampling, ADEQ also operated transmissometers and neph-elometers
in Phoenix and Tucson. Data from these instruments for 1998 and 1999
are presented in Table I.22. The data are separated into categories for all hours and
six hours. Each category is further summarized into the average visibility for the dirti-est
20 percent of the sampled hours, the mean visibility of all hours, and the cleanest
20 percent of the sampled hours.
Appendix I, 55 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 56
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 56
In addition to ADEQ’s program of monitoring statewide for regulatory purposes, four
special projects were undertaken by the Air Assessment Section of the Air Quality
Division during 1999 and the spring of 2000.
Douglas/Agua Prieta
The Douglas/Agua Prieta study was conducted to assess the temporal and spatial dis-tribution
of carbon monoxide and PM in the region. A dense monitoring network
also collected meteorological data, including vertical wind distribution using a wind
profiler. The study began in January of 1999 and ended in March of 2000. Several
monitoring scales were investigated with a north-south transect of instrumentation
crossing the border for the length of the study period and a shorter-term (about six
weeks) study of a smaller sample area with closely spaced particulate monitors. The
study has provided an enormous amount of data that is undergoing quality control
checks and analysis. Reports will be available in the near future.
Greenwood
In the Phoenix metropolitan area, a short term study to assess PM distribution in a
west Phoenix neighborhood was conducted in the spring of 2000. The reason for this
study was that in all of metropolitan Phoenix, only one neighborhood (residential
area) monitor has consistently violated the annual standard for PM10. Other sites
that violate this standard are classified as industrial or agricultural. Called “Green-wood,”
this monitoring site is about 100 yards south of Interstate 10 and just 30 feet
west of 27th Avenue in west-central Phoenix. In the 1999 Maricopa Association of
Governments’ PM10 SIP, the concentration of PM10 at Greenwood was the critical
value that exceeded the standard and had to be shown to meet the standard through
additional controls by 2006.
The study was designed to determine (1) which general sources are responsible for
the exceedances of the annual PM10 standard (50 μg/m3) and (2) the contribution
that vehicular traffic, both nearby and regional, makes to the ambient concentrations
of PM10. Conducted by ADEQ, this study was funded by both ADEQ and by the
Arizona Department of Transportation’s Highway Research Council.
Three sites were selected for the study: the Greenwood Site (the primary site, locat-ed
near the intersection of Interstate 10 and 27th Avenue), the West Phoenix Site
(39th Avenue and Earll) and the Auto Yard Site (33rd Avenue and Washington).
With the Greenwood Site as the primary site, the other two sites served as back-ground
sites. The West Phoenix Site is about one mile northwest of the primary site
and the Auto Yard Site is located about one mile southwest of the primary site.
The study consisted of intensive sampling of ambient fine (0-2.5 microns) and coarse
particulates (2.5-10.0 microns), ambient PM10 (0-10.0 microns), measurement of
carbon monoxide (CO) and measurements of wind speed, wind direction, and delta
temperature. 24-hour particulate samples (both quartz and Teflon filters) were taken
on an every sixth day cycle beginning March 19, 2000, and four six-hour samples
(both quartz and Teflon filters) were taken on an every sixth day cycle beginning
Appendix I, 57 Arizona Department of Environmental Quality 2000 Annual Report
March 22, 2000. All filter samples were sent to the Desert Research Institute, Reno,
NV for analysis. The fine and coarse quartz sample filters will be analyzed for carbon
and for ions (Cl-, NO3
- and SO4
--) . The fine and coarse Teflon sample filters will be
analyzed by x ray fluorescence analysis to determine their elemental constituents.
The analytical results will be used for Chemical Mass Balance (CMB) modeling in
order to attribute the fine, coarse, and PM10 particulates collected into general
source categories - i.e., vegetative burning (only during March), combustion, pri-mary
geological, secondary aerosols, etc. If possible, the combustion portion will be
broken into two subcategories, on-road and off-road motor vehicles. The profiles that
will be used in the CMB modeling are: (1) geological profiles developed from the
1989-90 Phoenix Brown Cloud Study, and (2) motor vehicle and combustion profiles
from the Northern Front Range Air Quality Study.
An emission inventory for the area will be created by ADEQ and used for dispersion
analysis. The dispersion analysis will be used to determine the relative magnitudes of
the various contributing sources.
Class I Area Visibility Program Update
Visibility monitoring in the national parks and wilderness areas of Arizona continued
during 1999 with the expansion to 12 aerosol (particulate) sampler sites and the
expansion to 14 nephelometer sites. The expanded network is described in Chapter
1 of this report. Plans were developed for monitoring the incoming amounts and
sources of visibility impairment at Organ Pipe Cactus National Monument, Hillside
and Meadview to capture transport from the west.
Photochemical Assessment Monitoring Stations Program Implementation
The 1990 federal Clean Air Act amendments (CAAA) include a provision requiring
more comprehensive and representative data on ozone air pollution, described in detail
in Chapter 1. The CAAA called for new regulations for enhanced monitoring of ozone,
its photochemical precursors (oxides of nitrogen and volatile organic compounds) and
meteorology. The revised regulations call for the establishment of Photochemical
Assessment Monitoring Stations (PAMS) in those ozone nonattainment areas classi-fied
as serious, severe or extreme. In 1997, EPA redesignated the Phoenix metropolitan
area from the “moderate” to the “serious” category for ozone nonattainment.
As a result of this redesignation, a PAMS site was established and more intensive
monitoring of ozone and its precursors began in 1999 at the JLG Supersite in
Phoenix. The supersite serves as a Type 2 PAMS site, which is designed to monitor
the magnitude and type of precursor emissions in the area where the maximum pre-cursor
emissions are expected to impact (typically near the downwind boundary of
the central business district). Volatile organic compound (VOC) samples were col-lected
every other day, three samples per day from May 15 through Sept. 29, 1999, in
both canisters and cartridges (carbonyl compounds). Instruments that measure con-centrations
of NOx and trace level NOy are operated on a continuous basis at the
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 58
site, as are instruments that measure ozone and total non-methane hydrocarbons.
Meteorological data (wind speed and direction, temperature and relative humidity)
are also collected at the supersite.
Two additional PAMS sites were scheduled for operation in 2000. A Type 3 PAMS
site was added, which is designed to characterize ozone precursor concentrations
occurring downwind from the area of maximum emissions (typically 10 to 30 miles
from the fringe of the urban area). This site is the Goldfield Ranger Station, on the
Salt River near the edge of Tonto National Forest and north of the Usery Mountain
Recreation Area. VOCs and nitrogen oxides will be measured at this site. The other
new PAMS site is the Vehicle Emissions Inspection station, where a radar wind pro-filer
will collect upper air meteorological data for determination of mixing heights.
This site will also be used to measure solar radiation.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 59
Whether air quality meets the standards is an important question, but one posed
more often is whether the air quality is improving or deteriorating. In Arizona,
because of the phasing out of leaded gasoline in the mid-1970s and the installation
of effective controls on copper smelters in the 1980s, the concentrations of both lead
and sulfur dioxide decreased rapidly. Although improvements have also been made
in the concentrations of carbon monoxide, ozone and particulates, the last two still
exceed air quality standards at some sites: the eight-hour ozone standard at several
sites in greater Phoenix and the 24-hour and annual PM10 standards at a few urban
and rural sites. Visibility, the aspect of the urban atmosphere that is most obvious to
the population, is measured continuously in Tucson and Phoenix. This discussion
examines the trends in these three common air pollutants throughout Arizona and
the urban visibility trends.
Carbon Monoxide
Since the mid to late 1970s, carbon monoxide concentrations have declined as much
as two-thirds. In Tucson, the maximum annual eight-hour concentration of carbon
monoxide at 22nd Street and Alvernon declined from 12 to four parts per million
(ppm). In Phoenix at 18th Street and Roosevelt (Central Phoenix), the decline was
from 23.0 to 7.1 ppm (Figures I.1 and I.2). The number of exceedances of the eight-hour
standard, 9 ppm, in Phoenix decreased from 75 to 0 at Central Phoenix. The
entire Phoenix network of carbon monoxide monitors recorded more than 100
exceedances each year from 1981 through 1986, with an average of 134 per year. No
exceedances were recorded by this network in 1997 and 1998, but a single
exceedance was recorded in 1999. Most of this improvement can be attributed to
Federal new-vehicle emission standards, augmented by emission reductions from the
Vehicle Inspection and Maintenance Program, which began in 1976, and the use of
oxygenated fuels in the winter, beginning in 1989.
Appendix I, 60 Arizona Department of Environmental Quality 2000 Annual Report
Ozone
One-Hour Ozone Concentrations
Maximum one-hour average ozone concentrations have remained steady in Tucson
and Yuma, but have declined in Phoenix since 1980 (Figure I.3). The Phoenix
decrease in ozone concentrations has been nowhere near as pronounced as its
declining carbon monoxide trend, but the net result has been similar: no
exceedances of the ozone standard were recorded in 1997-1999. Because of its rela-tively
high background level and its photochemical formation from hydrocarbons
and nitrogen oxides, changes in emissions would not be expected to translate into
proportional changes in concentrations. Recent atmospheric modeling in Phoenix
predicts that ozone concentrations should have remained constant from 1996-1999,
but the decrease in measured ambient concentrations contradicts these predictions.
Eight-Hour Ozone Concentrations
A new eight-hour ozone standard, promulgated by EPA in 1997, is expressed as the
three-year average of the annual fourth-highest concentration, not to exceed 0.08
parts per million. This standard was remanded to EPA in a May 14, 1999 court deci-sion.
Analysis of ambient ozone concentrations nationwide showed that the eight-hour
standard is likely to be exceeded in many areas where the one hour standard is
met. Phoenix falls into this category; Tucson and Yuma do not. Long-term trends of
the fourth-highest ozone concentrations in Tucson are fluctuating, but, overall,
steady, with the exception of Saguaro National Monument East, which shows a slight
increase (Figures I.4 and I.5).
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 61
Appendix I, 62 Arizona Department of Environmental Quality 2000 Annual Report
As the data presented in Table I.23 show, 24 of the 28 sites in greater Phoenix have
recorded annual fourth-highest ozone values in excess of the three-year average stan-dard
of 0.084 ppm in 1995-1999. The standard of 0.084 ppm is the de facto, or oper-ational
standard, in contrast to the statutory standard of 0.08 ppm. This operational
standard takes into account the precision of the instrumental method and the round-ing
off to the nearest 0.01 ppm. Half these sites exceeded the three-year average
standard in either 1995-1997, 1996-1998 or 1997-1999 (Figure I.6 and Table I.24).
Achieving this standard in Phoenix will undoubtedly be difficult, especially consider-ing
the relatively high concentrations in such background sites as Hillside (80 miles
northwest of Phoenix).
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 63
Appendix I, 64 Arizona Department of Environmental Quality 2000 Annual Report
Particulates
PM10
The concentrations of PM10 have decreased considerably throughout the state, in
both urban and rural settings. For example, annual PM10 concentrations in South
Phoenix averaged 63 μg/m3 from 1985 through 1989, but only 49 μg/m3 in 1995-97,
a decrease of 22 percent. Similar percentage decreases occurred from the beginning
to the end of the monitoring record at Central Phoenix and West Phoenix (Figures
I.7 and I.8). In 1999, however, the concentrations increased, presumably because of
the unusually dry weather from mid-September through the end of the year.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 65
In Tucson, the background site of Corona de Tucson and the rural site of Green Val-ley
have had steady, even trends of PM10, but the four long-term urban sites all show
substantial decreases. Orange Grove averaged 45.5 μg/m3 in 1985-86, but steadily
decreased in the next 15 years to an average concentration in 1997-98 of 27.5
μg/m3, which is a decrease of 40 percent. South Tucson, Prince Road and Broad-way/
Swan showed smaller, but substantial, decreases (Figure I.9). Similar to the
Phoenix monitoring sites, the 1999 concentrations in Tucson increased substantially
over their 1998 levels, again due to the drier weather.
These PM10 reductions in the urban settings can probably be attributed to a reduc-tion
of coarse particulate emissions from paving roads and alleys, from paving road
shoulders, and from better controls of construction dust emissions.
Throughout the state, PM10 concentrations have declined since 1985 at many sites.
Appendix I, 66 Arizona Department of Environmental Quality 2000 Annual Report
Consider a group of high concentration sites: Douglas, Hayden and Nogales concen-trations
have been cut in half, Payson and Paul Spur have been reduced three-fold,
and Rillito and Yuma have decreased 40 percent. In each of these localities, road
paving and better industrial dust controls can be given credit for most of the
improvement (Figure I.10).
PM10 concentrations at the sites with lower concentrations have decreased, as well,
with Ajo concentrations cut in half, Bullhead City two-thirds, and Safford by 15 per-cent.
Other lower concentration sites in the lower elevations were steady or slightly
decreasing (Figure I.11).
With the exception of Montezuma’s Castle, a background site with an even trend, all
of the higher-elevation, low-concentration sites showed decreasing trends for PM10.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 67
Clarkdale decreased 38 percent; Flagstaff, 69 percent; Joseph City, 45 percent; Nel-son,
45 percent; and Show Low, 56 percent. Part of these decreases may be attrib-uted
to cleaner-burning wood stoves and fireplaces (Figure I.12). What is encourag-ing
in these various sites is that not a single one shows an upward trend, whether
urban, industrial, agricultural or rural.
PM2.5
PM2.5 has not been monitored as long as PM10. The earliest measurements began in
1991 in the smaller cities and towns, 1994 in Tucson and 1995 in Phoenix. Slight
downward trends at the urban sites are apparent. Nogales, Yuma, and Flagstaff have
shown even trends, while Payson’s is significantly down by 39 percent. Exceedances
of the 1997 annual PM2.5 standard occurred for four years in Payson and for one
year in Higley. Payson, Nogales and the central area of Phoenix have the highest
concentrations of fine particulates. Flagstaff and the urban fringe of Tucson (the Tan-gerine
and Fairgrounds sites) have the lowest concentrations. These data are pre-sented
in Table I.25 and Figures I.13 to I.15.
Appendix I, 68 Arizona Department of Environmental Quality 2000 Annual Report
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 69
Appendix I, 70 Arizona Department of Environmental Quality 2000 Annual Report
Visibility
Optical measurements of visibility have been made continuously since 1993 in Tuc-son
and since 1994 in Phoenix. Light extinction − the degree to which sunlight is
reduced by its interaction with fine particles and gases in the atmosphere − is meas-ured
continuously with transmissometers. These measurements have been divided
into six categories: the mean of the dirtiest 20 percent of all hours, the mean of all
hours, and the mean of the cleanest 20 percent of all hours − for both the entire day
and the 5-11 a.m. period. Table I.26 and Figures I.16 and I.17 present these data.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 71
Tucson visibility shows improving trends in all six categories, although these trends
are not strong and are somewhat obscured by considerable year-to-year variability.
Phoenix has much stronger trends, but in the opposite direction: all six categories of
light extinction have steadily increased from 1994 to 1998. Because the cleanest 20
percent of the hours has increased about five times faster than the dirtiest 20 per-cent,
the increasing mean values have resulted because of a migration from the
cleanest 20 percent to the mean. If these trends continue, the mean value in just five
years will equal the dirtiest 20 percent value of 1998. This increase can be attributed
to increases in nitrogen oxides and carbonaceous fine particulate emissions from
motor vehicles; metropolitan Phoenix vehicle miles traveled increases about 3 per-cent
a year, and has now reached 64 million miles on an average weekday.
Appendix I, 72 Arizona Department of Environmental Quality 2000 Annual Report
Seasonal patterns also vary between the two cites, with the mean and dirtiest 20 per-cent
of all hourly light extinction values in Phoenix showing more pronounced win-ter
and fall maxima than the Tucson counterparts (Figure I.18). Both cities show
almost no seasonal variation in the cleanest 20 percent of all hours. The seasonal
light extinction values in Phoenix are considerably higher than Tucson’s: for the dirt-iest
20 percent of all hours, 52 percent higher in winter, 19 percent higher in spring,
13 percent higher in summer, and 49 percent higher in fall. These measurements of
the poorer visibility in Phoenix will come as no surprise to Arizonans familiar with
both airsheds.
Conclusions
Since monitoring of air pollutants began in the late 1960s in Arizona, considerable
progress has been made in reducing concentrations of lead, sulfur dioxide, and car-bon
monoxide. Lead has been reduced to near background levels; sulfur dioxide con-centrations
near copper smelters, which chronically exceeded the standards until the
mid-1980s, are now well within these standards; and carbon monoxide concentra-tions,
which regularly exceeded standards in neighborhoods and near busy intersec-tions
in Phoenix (and to a far lesser extent in Tucson), now meet the standards. One
hour ozone concentrations in Phoenix met the standard in 1997, 1998 and 1999, the
first years since monitoring began. Phoenix ozone concentrations in the 1980s and
early 1990s used to range as high as 0.15 to 0.18 parts per million (the standard is
0.12 ppm), in contrast to the highest, most recent reading of 0.14 ppm in 1996. Six
of 20 ozone monitoring sites in greater Phoenix exceeded the new eight-hour ozone
standard in 1996-1997.
Arizona Department of Environmental Quality 2000 Annual Report Appendix I, 73
Elevated concentrations of PM10 have been reduced substantially since the mid-
1980s, with decreases of 20 to 70 percent in the urban areas and in most smaller
cities and towns. In Payson and at some industrial sites, PM10 concentrations have
been reduced by as much as two-thirds. By 1998, monitored violations of the PM10
standard, a common occurrence at many sites only 10 years ago, were limited to a few
sites. Fine particulates concentrations (PM2.5) have decreased in Phoenix and Tucson
since 1995 and 1994, respectively; for example, at the centrally located Phoenix
Supersite, the decrease has been 21 percent; at 22nd and Craycroft, in east-central
Tucson, the decrease has been 24 percent. The Phoenix decreases are inconsistent
with the increasing trends in light extinction, caused primarily by small particles.
In spite of the continued growth in Arizona, with the exception of Phoenix visibility
in the last five years, not a single air pollutant at any site shows a consistent upward
trend. Most standards are met most of the time, with the exceptions being the eight-hour
ozone standard in Phoenix summers and the PM10 standards on both an
episodic and annual basis at those sites affected by localized dense emissions. These
improving air quality trends, resulting from control programs at the federal, state and
local levels, have improved the respiratory health of the citizenry and can be consid-ered
a testament to the public support for a cleaner environment.
Supplement A
Site Index
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Apache
St. Johns
(Sampling ended
5/99)
Carrizo Draw 34E 37' 109E 25' SRP NO, NO2,
NOX, PM10,
PM2.5
SPM Unknown Source Impact
St. Johns
(Sampling ended
5/99)
Mesa Parada 34E 35' 109E 25' SRP O3, NO, NO2,
NOX, PM10,
PM2.5
SPM Unknown Source Impact
Petrified Forest
National Park
1 mi. N Park Headquarters 35E 05' 109E 48' NPS IMPROVE, Pb Class I Regional Visibility
Springerville Coalyard 34E 20' 109E 09' TEP PM10 SPM Unknown Source Impact
Springerville Coyote Hills 34E 15' 109E 15' TEP SO2, NO, NO2,
NOX, PM10
SPM Unknown Source Impact
Cochise
Chiricahua
National
Monument
3.5 mi. W Monument
Headquarters
32E 00' 109E 23' NPS O3, MET, Pb,
IMPROVE,
CASTNET
Class I Regional Visibility
Douglas - ADOT Ave. B and 21st Street 31E 23' 109E 32' ADEQ CO, PM10,
PM2.5
SPM Neighborhood Population
Douglas - Border 1051 Lawrence Ave. 31E 24' 109E 32' ADEQ MET SPM Neighborhood Population
Douglas -
Cemetery
Calvary Cemetery, 1505 5th
St.
32E 20' 109E 33' ADEQ CO, PM10,
PM2.5
SPM Neighborhood Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Douglas - Cochise
College
4190 W. Hwy 80 31E 00' 109E 00' ADEQ MET SPM Neighborhood Population
Douglas - Red
Cross
1445-1449
15th Street
31E 20' 109E 30' ADEQ PM10, PM2.5, Pb SLAMS Neighborhood Population
Douglas - Vortac Bisbee/Douglas Airport, 10
mi. N of Douglas
31E 28' 109E 36' ADEQ PM10, PM2.5 SPM Neighborhood Population
Muleshoe Ranch Muleshoe Ranch Preserve 32E 21' 110E 14' ADEQ IMPROVE,
MET, Bscat
Class I Regional Visibility
Naco 156 W. Maricopa Rd.,
Border Patrol Crossing
31E 20' 109E 57' ADEQ PM10 SPM Neighborhood Population
Paul Spur Naco Rd. 31E 22' 109E 44' ADEQ PM10, PM2.5,
Wind
SLAMS
(PM10)
Middle Source Impact
Rucker Canyon Chiricahua National Forest 31E 47' 109E 18' ADEQ IMPROVE,
MET, Bscat
Class I Regional Visibility
Coconino
Flagstaff - ADOT ADOT Yard, 5701 E.
Railroad Ave.
35E 12' 111E 37' ADEQ PM10 SPM Neighborhood Maximum
Concentration
Flagstaff - Middle
School
Middle School, 755 N.
Bonito
35E 12' 111E 38' ADEQ PM10, PM2.5 SLAMS Neighborhood Population
Grand Canyon
National Park -
Hance
South Rim, 2.5 mi West of
Village
36E 04' 112E 11' NPS O3, Pb, MET
IMPROVE,
CASTNET
Class I Regional Visibility
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Grand Canyon
National Park -
Indian Gardens
Indian Gardens, 4.5 mi from
Bright Angel trailhead
36E 07' 112E 13' NPS IMPROVE, Pb Class I Regional Visibility
Page Glen Canyon
Dam
36E 55' 111E 24' SRP O3, NO, NO2,
NOX, SO2,
PM10
SPM Urban Source Impact
Sycamore Canyon Camp Raymond 35E 02' 111E 59' ADEQ IMPROVE,
MET, Bscat
Class I Regional Visibility
Sedona Post Office 34E 52' 111E 45' ADEQ PM10 SPM Neighborhood Population
Tusayan Airport 35E 57' 111E 59' ADEQ PM10, PM2.5 SPM Regional Visibility
Gila
Hayden - Old Jail Jail on Canyon Dr. 33E 00' 110E 47' ADEQ SO2, Pb, PM10 SLAMS
(SO2 and
PM10)
Neighborhood Source Impact
Hayden - Old Jail Jail on Canyon Dr. 33E 00' 110E 47' ASARCO SO2 SPM Neighborhood Source Impact
Hayden - Garfield
Ave.
Garfield Ave. 33E 00' 110E 47' ASARCO SO2 SPM Neighborhood Source Impact
Hayden - Junction Junction 33E 00' 110E 50' ASARCO SO2 SPM Unknown Source Impact
Hayden -
Montgomery
Ranch
Montgomery Ranch 33E 00' 110E 47' ASARCO SO2 SPM Unknown Source Impact
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
McFadden McFadden Peak, Sierra
Ancha Wilderness
33E 53' 110E 58' ADEQ IMPROVE,
MET, Bscat
Class I Regional Visibility
Miami - ADEQ
Ridgeline
Ridgeline - 4030 Linden St. 33E 23' 110E 52' ADEQ SO2 SPM Neighborhood Source Impact
Miami - Ridgeline Ridgeline 33E 23' 110E 52' CMMC PM10, PM2.5 SPM Neighborhood Source Impact
Miami - Golf
Course
Golf Course 33E 23' 110E 52' CMMC PM10, PM2.5 SPM Neighborhood Source Impact
Miami - Jones Jones Ranch CMMC SO2 SPM Neighborhood Source Impact
Miami - Town
Site
CMMC SO2 SPM Neighborhood Source Impact
Payson 204 W. Aero Dr. 34E 14' 111E 20' ADEQ PM10, PM2.5, Pb SPM Neighborhood Population
Rye 34E 06' 111E 22' ADEQ O3, MET SPM Regional Transport
Tonto National
Monument
Maintenance Station 33E 39' 111E 07' NPS IMPROVE, Pb Class I Regional Visibility
Winkleman 110E45' 32E 59' ASARCO SO2 SPM Regional Source Impact
Graham
Safford 523 Tenth Ave. 32E 49 109E 43' ADEQ PM10, PM2.5 SLAMS Neighborhood Population
Maricopa
ASU West 4701 W. Thunderbird Rd. 33E 36' 112E 09' ADEQ PM10, PM2.5 SPM/
Urban Haze
Neighborhood Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Blue Point Usery Pass &
Bush Highway
33E 33' 111E 36' MCESD O3 NAMS Urban Maximum
Concentration
Central Phoenix 1845 E. Roosevelt 33E 27' 112E 02' MCESD O3, CO, SO2
NO, NO2,
NOX, PM10,
MET
NAMS Neighborhood Population
Chandler 1475 E. Pecos Rd. 33E 17' 111E 49' MCESD O3, PM10 NAMS Neighborhood Population
Durango
Complex
2702 AC
Esterbrook
Blvd.
33E 25' 112E 07' MCESD PM10 SLAMS Middle Maximum
Concentration
Estrella 15099 W Casey Abbott Dr.,
Goodyear
33E 23' 112E 22' ADEQ PM10, PM2.5 SPM/
Urban Haze
Neighborhood Population
Falcon Field 4530 E Mckellips, Mesa 33E 27' 112E 04' MCESD O3, Wind SLAMS Urban Population
Fountain Hills 16426 E. Palisades 33E 37' 111E 43' MCESD O3, MET NAMS Neighborhood Maximum
Concentration
Gilbert 535 N. Lindsay Road 33E 22' 111E 46' MCESD CO, PM10,
MET
SLAMS Neighborhood Population
Glendale 6000 W. Olive 33E 33' 112E 12' MCESD O3, CO, PM10,
MET
SLAMS
(O3, CO)
NAMS
(PM10)
Neighborhood Population
Higley 15500 S. Higley Rd. 33E 18' 111E 43' ADEQ PM10, PM2.5 SPM Neighborhood Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Humboldt
Mountain
Tonto National Forest 33E 59' 111E 47' MCESD/
ADEQ
O3, IMPROVE,
MET, Bscat
Class I Regional Background/
Transport
Lake Pleasant Lake Pleasant 33E 51' 112E 19' MCESD O3 SLAMS Regional Population
Maryvale 6180 W. Encanto 33E 28' 112E 20' MCESD O3, CO, PM10,
MET
SLAMS Neighborhood Population
Mesa 370 S. Brooks (N. of
Broadway)
33E 24' 111E 51' MCESD O3, CO, PM10,
Wind, Pressure
SLAMS Neighborhood Population
Mt. Ord - ADEQ Mazatzal Mountains 33E 55' 111E 25' ADEQ Bscat, MET SPM Regional Maximum
Concentration
Mt. Ord -
MCESD
Mazatzal Mountains 33E 55' 111E 25' ADEQ O3, IMPROVE,
Wind
SLAMS Regional Maximum
Concentration
Mt. Ord - NPS Mazatzal Mountains 33E 55' 111E 25' ADEQ IMPROVE SPM, Class
I
Neighborhood Population
North Phoenix 601 E. Butler 33E 33' 112E 04' MCESD O3, CO, PM10,
MET
SLAMS Neighborhood Population
Palo Verde 36248 W. Elliot Rd. 33E 20' 112E 50' ADEQ O3, NO, NO2,
NOX, Pb, PM10,
PM2.5
SPM Regional Background
Phoenix - Bank
One
201 N. Central 33E 15' 112E 02' ADEQ MET SPM Regional Upper air temp
Phoenix - Desert
West Recreation
Center
2602 N. 23rd Ave. 33E 28' 112E 12' ADEQ PM2.5 SPM Neighborhood Maximum
Concentration
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Phoenix -
Emergency
Management
2035 N. 52nd St. 33E 26' 111E 57' MCESD O3 SLAMS Neighborhood Population
Phoenix - Grand
Avenue
Grand / 27 Ave./Thomas 33E 28' 112E 07' ADEQ CO SPM Microscale Maximum
Concentration
Phoenix -
Greenwood,
ADEQ
I-10 and 27th Avenue 33E 28' 112E 07' ADEQ PM10, PM2.5, Pb SPM Microscale Maximum
Concentration
Phoenix -
Greenwood,
MCESD
I-10 and 27th Avenue,
Phoenix
33E 28' 112E 07' MCESD CO, NO, NO2,
NOX, PM10,
MET
SLAMS Middle Population
Phoenix - JLG
Supersite
4530 N. 17 Ave. 33E 30' 112E 05' ADEQ O3, CO, NO,
NO2, NOX,
Met, PM10,
PM2.5
SPM/
Urban Haze
Neighborhood Population
Phoenix -Magnet
Traditional
2602 N. 23 Ave. 33E 28' 112E 06' ADEQ PM2.5 SPM Neighborhood Maximum
Concentration
Phoenix - Post
Office (Closed
3/31/99)
3905 N. 7th Ave. 33E 30' 112E 05' ADEQ CO SLAMS Neighborhood Population
Phoenix - Salt
River
3045 S. 22nd Ave. 33E 21' 112E 06' MCESD NO, NO2,
NOX, PM10
SPM Middle Maximum
Concentration
Phoenix -
Transmissometer
Phx Baptist Hosp. To
Quality Hotel
33E 29' 112E 04' ADEQ Bext SPM/
Urban Haze
Urban Urban Haze
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Phoenix - Vehicle
Emissions
600 N. 40th St. 33E 27' 112E 00' ADEQ RH, Wind,
Delta
Temperature
SPM Regional Background
Phoenix - West
Indian School
W Indian School/ 75 Ave.,
Phoenix
33E30' 112E 08' MCESD CO, MET NAMS Micro Maximum
Concentration/
Source Impact
Pinnacle Peak 25000 N Windy Walk,
Scottsdale
33E 42' 111E 51' MCESD O3, MET SLAMS Urban Maximum
Concentration
Rio Verde 25608 N. Forest Rd., MCSD
Substation
33E 43' 111E 40' MCESD O3 SLAMS Urban Maximum
Concentration
Salt River
Pima - Maricopa
10005 E. Osborn, Phx 33E 30' 111E 50' ADEQ O3, NO, NO2,
NOX,
SLAMS Urban Transport
South Phoenix 4732 S. Central 33E 24' 112E 04' MCESD CO, O3, PM10,
MET
NAMS
(PM10)
SLAMS
(CO, O3)
Neighborhood Population
South Scottsdale 2857 N. Miller 33E 28' 111E 55' MCESD O3, CO, NO,
NO2, NOX,
SO2, PM10,
MET
SLAMS
(CO)
NAMS (O3,
NO, NO2,
NOX, SO2,
PM10
Urban/
Neighborhood
Population
Tempe 3340 S. Rural Rd. 33E 23' 111E 55' ADEQ PM10, PM2.5 SPM Neighborhood Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
West Chandler 163 S. Price Rd. 33E 18' 111E 53' MCESD O3, CO, PM10,
MET
SLAMS Neighborhood Population
West Phoenix 3847 W. Earll 33E 29' 112E 08' MCESD O3, CO, NO,
NO2, NOX,
PM10
SLAMS Neighborhood Population
Mohave
Bullhead City -
ADEQ
990 Highway 95 35E 05' 114E 35' ADEQ PM10, PM2.5 SPM Neighborhood Population
Bullhead City -
Alonas Way
1285 Alonas Way, Bullhead
City
35E 07' 114E 35' SCE NO, NO2,
NOX, SO2,
PM10
SPM Neighborhood Population
Fort Mohave 2230 Joy Lane 34E 51' 114E 35' ADEQ PM10, PM2.5 SPM Neighborhood Maximum
Concentration
Kingman - Praxair I-40 and Griffith Rd. 35E 00' 114E 08' Praxair PM10 SPM Middle Source Impact
Navajo
Joseph City - APS Cholla Generating Station 34E 57' 110E 20' APS PM10 SPM Unknown Source Impact
Joseph City - APS Third and Tanner 34E 57' 110E 18' APS PM10 SPM Unknown Source Impact
Show Low Deuce of Clubs Ave. 34E 15' 110E 02' ADEQ PM10 SPM Neighborhood Population
Pima
Ajo ADOT Well Rd. 32E 25' 112E 50' ADEQ PM10, Wind SLAMS Neighborhood Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Green Valley -
ADEQ (closed
8/24/99)
7515 W. Magee Ranch Rd.
(Sierrita, Elam Ranch)
31E 54' 111E 10' ADEQ SO2 SPM Middle Source Impact
Green Valley -
PDEQ
245 W. Esperanza 31E 52' 110E 59' PDEQ PM10 SLAMS Middle Source Impact
Organ Pipe Cactus
National
Monument
1mi SSW Visitor Center 31E 58' 112E 48' ADEQ PM10, PM2.5, Pb SLAMS
(PM10)
Regional Background/
Transport
Rillito - ADEQ 8820 W. Water 32E 25' 111E 10' ADEQ PM10, PM2.5 SLAMS Neighborhood Source Impact
Rillito - APCC 8820 W. Water 32E 27' 110E 09' APCC PM10 SPM Neighborhood Source Impact
Saguaro Park South Old Spanish Trail,
Saguaro Natl. Park, East
Unit
32E 10' 110E 44' PDEQ O3 SPM Neighborhood Population
South Tucson 1810 S. 6 Ave. 32E 12' 110E 58' PDEQ/
ADEQ
PM10, PM2.5 SLAMS Neighborhood Population
Tucson -
Alvernon
near 22ndAve./
Alvernon
32E 12' 110E 54' PDEQ CO NAMS Micro Population
Tucson -
Broadway/ Swan
4625 E. Broadway 32E 13' 110E 53' PDEQ PM10 NAMS Middle Population
Tucson - Cherry 2745 N. Cherry 32E 15' 110E 56' PDEQ CO SPM Neighborhood Population
Tucson -
Children’s Park
400 W. River Road 32E 17' 110E 58' PDEQ O3, NO2, PM2.5 SLAMS Urban/
Neighborhood
Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Tucson -
Convention
Center
260 S. Church Ave. 32E 13' 110E 58' PDEQ PM10 SPM Neighborhood Population
Tucson - Corona
De Tucson
22000 S. Houghton
Rd .
32E 00' 110E 47' PDEQ/
ADEQ
PM10 SPM/
Urban Haze
Regional Background
Tucson -
Craycroft
near 22 Ave./ Craycroft 32E 12' 110E 52' PDEQ CO, O3, SO2,
NO, NO2,
NOX, PM10,
PM2.5
SPM/
Urban Haze
Neighborhood Population
Tucson -
Downtown
151 W. Congress 32E 13' 110E 58' PDEQ O3, CO, PM10 SLAMS Neighborhood Population
Tucson -
Fairgrounds
11330 S. Houghton 32E 03' 110E46' PDEQ O3 SLAMS Neighborhood Population
Tucson -
Mountain
Saguaro National Park -
West Unit
32E 17' 111E 10' ADEQ IMPROVE,
Bscat
Class I Regional Visibility
Tucson - Orange
Grove
3401 W. Orange Grove Rd. 32E 19' 111E 02' PDEQ/
ADEQ
PM10, PM2.5 SPM/
Urban Haze
Neighborhood Maximum
Concentration/
Population
Tucson - Prince
Road
1016 W. Prince Rd. 32E 16' 110E 59' PDEQ PM10 NAMS Neighborhood Population
Tucson - Santa
Clara
6910 S. Santa Clara Ave. 32E 07' 110E 58' PDEQ PM10 SPM Middle Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Tucson -
Tangerine
12101 N. Camino De Oeste,
Tucson
32E 25' 110E 04' PDEQ O3, PM10 SLAMS Neighborhood Population
Tucson
Transmissometer
U of A Clinical Sci. to Pima
DEQ
32E 13' 110E 57' PDEQ/
ADEQ
Bext SPM/
Urban Haze
Urban Urban Haze
Tucson - U of A
Central
1100 N. Fremont Ave 32E 13' 110E 57' PDEQ/
ADEQ
PM10, PM2.5,
Bscat
SPM/
Urban Haze
Neighborhood Population
Pinal
Apache Junction 3955 E Superstition Blvd. -
TE
33E 25' 111E 30' PCAQCD PM2.5 SPM Neighborhood Population
Apache Junction -
Highway Yard
SW Corner Hwy 88 and
Superstition Rd.
33E 25' 111E 32' PCAQCD O3, CO, PM10
MET
SPM Neighborhood Population
Apache Junction -
Miller (closed
12/99)
NW Corner McKillips and
Bulldog Mine Rd.
33E 27' 111E 32' PCAQCD PM10 SPM Neighborhood Population
Casa Grande
Airport
660 W. Aero Drive 32E 54' 111E 46 PCAQCD O3, CO,
MET
SPM Neighborhood Population
Casa Grande -
County
Fairgrounds
(EMC)
Eleven-Mile Corner Road,
south of SR 287
32E 52' 111E 34 PCAQCD PM10 SPM Middle Population
Casa Grande DES 401 Marshall Rd. 32E 52' 111E 45' PCAQCD PM10, PM2.5 SPM Neighborhood Population
Coolidge NE Corner of Pacific St. and
Broadway
32E 58' 111E 30' PCAQCD PM10 SPM Neighborhood Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Eloy 620 N. Main Street 32E 45' 111E 33' PCAQCD PM10 SPM Neighborhood Population
Hayden Junction Junction 33E 00' 110E 50' ASARCO SO2 SPM Unknown Source Impact
Mammoth 4th Street and Corona 32E 43
'
110E 39' PCAQCD PM10 SPM Neighborhood Population
Pinal Air Park Between Red Rock and
Marana at the Number 2
Water Well
32E 31' 111E 20' PCAQCD PM10 SPM Neighborhood Background/
Transport
San Manuel First and Douglas Ave. 32E 36' 110E 38' ADEQ SO2 SLAMS Neighborhood Source Impact
San Manuel Townsite 32E 36' 110E 38' BHP SO2 SPM Neighborhood Source Impact
San Manuel Dorm site 32E 37' 110E 63' BHP SO2 SPM Neighborhood Source Impact
San Manuel Hospital 32E 37' 110E 38' BHP SO2 SPM Neighborhood Source Impact
Stanfield 36697 W. Papago Drive 32E 53' 111E 57 PCAQCD PM10 SPM Neighborhood Population
Santa Cruz
Nogales 300 N. Morley Ave 31E 21' 110E 57' ADEQ PM10, PM2.5, Pb SLAMS
(PM2.5)
other SPM
Neighborhood Population
Yavapai
Clarkdale -
ADEQ
School, 1615 Main Street 34E 46' 112E 03' ADEQ PM10, PM2.5, Pb SLAMS
(PM10)
Neighborhood Population
Clarkdale - NW NW of Cement Plant 34E 45' 112E 05' PCC PM10, PM2.5, Pb SPM Unknown Source Impact
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Clarkdale - SE SE of CTI Flyash Silo 34E 45' 112E 05' PCC PM10, PM2.5, Pb SPM Unknown Source Impact
Hillside Sheriff’s Repeater Station 34E 25' 112E 54' ADEQ O3, Pb, PM10,
PM2.5
SPM Regional Background/
Transport
Nelson 1 mile North, Flintkote Lime
Plant
35E 34' 113E15' ADEQ PM10, PM2.5 SLAM
(PM10)
Neighborhood Source Impact
Prescott 22 S. Cortez 34E 32' 112E 28' ADEQ PM10 SPM/
Urban Haze
Neighborhood Population
Sycamore Canyon Camp Raymond 35E 02' 111E 59' ADEQ MET, Bscat Class I Regional Visibility
Yarnell 17175 Sunrise Road 34E 13' 112E 45' ADEQ PM10 SPM Neighborhood Population
Yuma
Yuma AZ Western College 32E 40' 114E 38' ADEQ O3 SPM Neighborhood Maximum
Concentration
Yuma Juvenile Center,
2795 Ave. B
32E 40' 114E 39' ADEQ PM10, PM2.5 SLAMS Neighborhood Population
Sonora, Mexico
Agua Prieta -
Fire Station
Calle 6 and Ave. 15 31E19' 109E33' ADEQ CO, PM10,
PM2.5
SPM Neighborhood Population
Agua Prieta -
Companie Federale
Electric
Hwy 2 and
Ave. 4
31E18' 109E33' ADEQ CO,
PM10, PM2.5,
SPM Neighborhood Population
County and
City or Site
Site
Address
Latitude
Longitude
Site
Operator
Parameters
Measured
Classification
Scale
Objective
Nogales - Fire
Station
Ave. Alaro Obregon and
Calle Gonzalez
31E19' 110E57' ADEQ PM10, PM2.5 SPM Neighborhood Population
Site Index Table Abbreviations and Notes
Abbreviations
ADEQ Arizona Department of Environmental Quality
APCC Arizona Portland Cement Co.
APS Arizona Public Service
ASARCO ASARCO, Inc.
Bext Light extinction
Bscat Light scattering
BHP BHP Copper, Inc.
CASTNET Clean Air Status and Trends Network
CFR Code of Federal Regulations
Class I Type of area of visibility protection
CMMC Cyprus Miami Mining Co.
CMSA Consolidated Metropolitan Statistical Area
CO Carbon Monoxide
Delta Difference between two levels of temperature measurements
IMPROVE Interagency Monitoring of Protected Visual Environments
MCESD Maricopa County Environmental Services Department
MET Meteorological measurements (wind, temperature, relative humidity)
MSA Metropolitation Statistical Area
NAMS National Air Monitoring Station
NO Nitric oxide
NO2 Nitrogen dioxide
NOX Sum of NO and NO2
NPS National Park Service
O3 Ozone
PAMS Photochemical Assessment Monitoring Station
Pb Lead
PCC Phoenix Cement Company
PDEQ Pima County Department of Environmental Quality
PCAQCD Pinal County Air Quality Control Division
PM2.5 Particulate matter < 2.5 microns
PM10 Particulate matter < 10 microns
Pressure Barometric air pressure
RH Relative Humidity
SCE Southern California Edison
SIP State Implementation Plan
SLAMS State and Local Air Monitoring Station
SO2 Sulfur Dioxide
SPM Special Purpose Monitor
SRP Salt River Project
TEP Tucson Electric Power
USFS U.S. Forest Service
Wind Wind speed and direction
WMAT White Mountain Apache Tribe
Notes
Sites shown in the site index table are based on the best information available at the date of publication.
All site information will be verified for inclusion in the next annual report.
For More Information
Arizona Department of Environmental Quality - www.adeq.az.state.us
Maricopa County Air Quality Information - www.maricopa.gov/sbeap/airday.htm
Pima County Air Quality Information - www.deq.co.pima.az.us
EPA National Ozone Mapping Program - www.epa.gov/airnow
EPA Air Quality Database - www.epa.gov/airsdata
EPA Information about the Environment - www.epa.gov
Supplement B
Maps
Ambient Air Monitoring Locations in Arizona by Site Operator
Metropolitan Phoenix Ozone, Carbon Monoxide and Particulate
Matter Monitoring Sites
Metropolitan Tucson Ozone, Carbon Monoxide and Particulate
Matter Monitoring Sites