### Technical Support Document for the State of Arizona - Page 1 of 19 

## Technical Support Document for 2008 Ozone NAAQS Des ignations



# Arizona Area Designations for the 2008 Ozone National Ambient Air Quality Standards

The table below identifies the areas and associated counties or parts of counties in Arizona that EPA intends to designate as nonattainment for the 2008 ozone national ambient air quality standards (2008 NAAQS). In accordance with section 107(d) of the C lean Air Act, EPA must designate an area “nonattainment” if it is violating the 2008 ozone N AAQS or if it is contributing to a violation of the 2008 ozone NAAQS in a nearby area. The technical a nalyses supporting the boundaries for the individual nonattainment areas are provided below.

Intended Nonattainment Areas in Arizona

Area Arizona’s Recommended Nonattainment Counties EPA’s Intended Nonattainment Counties

Phoenix-Mesa* Maricopa County (partial) Pinal County (partial) Maricopa County (partial) Pinal County (partial) *The intended Phoenix-Mesa area includes areas of I ndian country. Table 1 below identifies the areas of Indian country that EPA intends to designate as part of the nonattainment area.

Designation of a state area may also affect Indian country. Areas of Indian country are located within the boundaries of the counties EPA intends to include a s the Phoenix-Mesa nonattainment area. Designation of areas of Indian country is discussed further in the following technical analysis.

EPA intends to designate the remaining counties, po rtions of counties, and areas of Indian country in Arizona that are not listed in the table above as “ unclassifiable/attainment” for the 2008 ozone NAAQS

. The analysis below provides the basis for intended nonattainment area boundaries. It relies on our analysis of which monitors are violating the 2008 o zone NAAQS, based on certified air quality monitoring data from 2008-2010, and an evaluation o f whether nearby areas are contributing to such violations. EPA has evaluated contributions from n earby areas based on a weight of evidence analysis considering the factors identified below. EPA issu ed guidance on December 4, 2008 that identified these factors as ones EPA would consider in determi ning nonattainment area boundaries and recommended that states consider these factors in m aking their designations recommendations to EPA 1 

## :

1. Air quality data (including the design value calcul ated for each federal reference method (FRM) or federal equivalent method (FEM) monitor in the a rea); 2. Emissions and emissions-related data (including loc ation of sources and population, amount of emissions and emissions controls, and urban growth patterns); 3. Meteorology (weather/transport patterns); 4. Geography and topography (mountain ranges or other basin boundaries); and 5. Jurisdictional boundaries (e.g., counties, air dist ricts, existing nonattainment areas, Indian country, metropolitan planning organizations (MPOs) ).

1 

### The December 4, 2008 guidance memorandum “Area Des ignations for the 2008 Revised Ozone National Ambie nt Air Quality Standards” refers to 9 factors. In this te chnical support document we have grouped the emissi ons-related factors together under the heading of “Emissions and Emissi ons-Related Data,” which results in 5 categories of factors.

### Technical Support Document for the State of Arizona - Page 2 of 19



## Ground-level ozone generally is not emitted directl y into the air, but is created by chemical reaction s between oxides of nitrogen (NO x 

## ) and volatile organic compounds (VOC) in the prese nce of sunlight. Because NO x 

## and VOC emissions from a broad range of sources ov er a wide area typically contribute to violations of the ozone standards, EPA believes it is important to consider whether there are contribu ting emissions from a broad geographic area. Accordingl y, EPA chose to examine the 5 factors with respect to the larger of the Combined Statistical Area (CSA ) or Core Based Statistical Area (CBSA) associated with the violating monitor(s). 2 

## All data and information used by EPA in this eval uation are the latest available to EPA and/or the latest information prov ided to EPA by states or tribes.

In EPA’s designations guidance for the 2008 ozone N AAQS, EPA recommended examining CSA/CBSAs because certain factors used to establish CSAs and CBSAs are similar to the factors EPA is using in this technical analysis to determine if a nearby area is contributing to a violation of the 2 008 ozone NAAQS. Congress required a similar approach in 1990 for areas classified as serious or above for the 1-hour ozone standard and EPA used the same basic approach in the designation process for the 1997 ozone NAAQS. Where a violating monitor is not located in a CSA or CBSA, EPA’s guidance recommended using the boundary of the county contai ning the violating monitor as the starting point fo r considering the nonattainment area’s boundary. Pho enix-Mesa-Glendale is defined by the Office of Management and Budget (OMB) as a metropolitan stati stical area (MSA) and is comprised solely of Maricopa and Pinal Counties. The Phoenix-Mesa-Glen dale MSA is not part of a larger CSA or CBSA.

Technical Analysis for Phoenix-Mesa

Figure 1 is a map of the existing Phoenix-Mesa nona ttainment area. The map provides other relevant information including the locations and design valu es of air quality monitors, county names and boundaries, and indicates EPA’s intended nonattainm ent designation. Also shown is the boundary of the existing area that is designated nonattainment. Se e Map 1 in Appendix 1 (also included in Factor 1 below) for a detailed map of the partial county bou ndaries that EPA intends to use for the nonattainme nt area boundary.

2 

### Lists of CBSAs and CSAs and their geographic compo nents are provided at www.census.gov/population/www/metroareas/metrodef.h tml . The lists are periodically updated by the Offic e of Management and Budget. EPA used the most recent up date, based on 2008 population estimates, issued on December 1, 2009 (OMB Bulletin No. 10-02).

### Technical Support Document for the State of Arizona - Page 3 of 19 

## Figure 1

For purposes of the 1997 8-hour ozone NAAQS, portio ns of Maricopa and Pinal Counties were designated nonattainment. Pinal County was not inc luded in the nonattainment area for the 1-hour ozone NAAQS. However, for the 1997 8-hour ozone NA AQS, EPA designated an area that included the 1-hour nonattainment area and added Apache Junc tion, a portion of Pinal County. This small city was part of the Phoenix PM 10 

## (particulate matter greater than 10 micrometers) n onattainment area. The Apache Junction portion of Pinal County was added t o the Phoenix 1997 8-hour ozone nonattainment area partly because of its PM 10 

## nonattainment status, and partly because its popul ation is associated with the greater Phoenix metropolitan area.

In March 2009, Arizona recommended that the same tw o partial counties, Maricopa and Pinal, be designated as “nonattainment” for the 2008 ozone NA AQS based on air quality data from 2006-2008, and additionally recommended extending the nonattai nment boundaries at two locations in Maricopa County, and one location in Pinal County (letter fr om Janice Brewer, Governor, State of Arizona, to Laura Yoshii, Acting Regional Administrator, U.S. E PA Region IX, March 12, 2009 (hereafter, “ADEQ 2009 Recommendations”)). ADEQ updated its 2009 rec ommendation on December 1, 2011 based on air quality data from 2008-2010 and preliminary dat a for 2009-2011. In its updated recommendation, the state continued to recommend extending the nona ttainment boundary in two locations in Maricopa County, but withdrew its previous recommendation to extend the nonattainment boundary in Pinal County (letter from Henry R. Darwin, Director, Ariz ona Department of Environmental Quality, to Jared

### Technical Support Document for the State of Arizona - Page 4 of 19



## Blumenfeld, Regional Administrator, U.S. EPA Region IX, December 1, 2011 (hereafter, “ADEQ 2011 Recommendations”)). The 2009 and 2011 recommendati ons are based on data from Federal Equivalent Method (FEM) monitors sited and operated in accorda nce with 40 CFR Part 58.

In March 2009, the Gila River Indian Community reco mmended that portions of Gila River lands in Maricopa and Pinal Counties be designated as “attai nment” for the 2008 ozone NAAQS (letter from William Rhodes, Governor, Gila River Indian Communi ty, to Laura Yoshii, Acting Regional Administrator, U.S. EPA Region IX, March 11, 2009).

In March 2009, the Salt River Pima-Maricopa Indian Community recommended that portions of Salt River lands in Maricopa County be designated as “at tainment/unclassifiable” for the 2008 ozone NAAQS (letter from Martin Harvier, Vice President, Salt River Pima-Maricopa Indian Community, to Laura Yoshii, Acting Regional Administrator, U.S. E PA Region IX, March 9, 2009).

In March 2009, the Tohono O’odham Nation of Arizona recommended that portions of Tohono O’odham lands in Maricopa, Pinal, and Pima Counties be designated as “attainment/unclassifiable” for the 2008 ozone NAAQS (letter from Ned Norris, Chair man, Tohono O’odham Nation, to Laura Yoshii, Acting Regional Administrator, U.S. EPA Region IX, March 11, 2009).

After considering these recommendations and based o n EPA's technical analysis described below, EPA intends to designate two partial counties in Arizon a and areas of Indian country (identified in Table 1 below) as “nonattainment” for the 2008 ozone NAAQS as the Phoenix-Mesa multi-jurisdictional nonattainment area.

Table 1. State’s and Tribe’s Recommended and EPA’s Intended Designated Nonattainment Counties or Areas of Indian country for Phoenix-Mesa.

Phoenix-Mesa State and Tribe-Recommended Nonattainment Counties or Areas of Indian country EPA Intended Nonattainment Counties or Areas of Indian country Maricopa County Maricopa County (p) Maricopa County (p) Pinal County Pinal County (p) Pinal County (p) Fort McDowell Yavapai Nation N/A 1 

## Fort McDowell Yavapai Nation

Salt River Pima-Maricopa Indian Community Attainment/unclassifiable Salt River Pima-Maricopa Indian Community Tohono O'odham Nation of Arizona 2 

## Attainment/unclassifiable Tohono O'odham Nation of Arizona (p) p = partial EPA intended modifications to state or tribe recomm endations are shown in bold

. 1 

## Tribe did not submit a recommendation.
2 

## Tohono O’odham has non-contiguous land in the inte nded Phoenix-Mesa nonattainment area, in the intended attainment area portions of Pinal County a nd the intended attainment area of Pima County. Non-contiguous lands of Tohono O’odham will designa ted with the surrounding areas. This technical analysis addresses only those areas of Indian count ry within the intended Phoenix-Mesa nonattainment

area.

### Technical Support Document for the State of Arizona - Page 5 of 19



## Factor Assessment


# Factor 1: Air Quality Data

For this factor, we considered 8-hour ozone design values in parts per million (ppm) for air quality monitors in counties in the existing 1997 8-hour oz one Phoenix-Mesa nonattainment area, based on data from the 2008-2010 period (i.e., the 2010 design va lue, or DV), which are the most recent years with fully-certified air quality data. A monitor’s DV i s the metric or statistic that indicates whether th at monitor attains a specified air quality standard. The 2008 ozone NAAQS are met at a monitor when the annual fourth-highest daily maximum 8-hour average concentration, averaged over 3 years, is 0.075 ppm (75 parts per billion (ppb)) or less. A DV is only valid if minimum data completeness criteria ar e met. See 40 CFR part 50 Appendix P. Where several monitors are located in a county (or a designated nonattainment area or maintenance area), the DV for the county or area is determined by the monitor with the highest level.

[Note: Monitors that are eligible for providing de sign value data generally include State and Local A ir Monitoring Stations (SLAMS) that are sited in accor dance with 40 CFR Part 58, Appendix D (Section 4.1) and operating with a federal reference method (FRM) or federal equivalent method (FEM) monitor that meets the requirements of 40 CFR part 58, appe ndix A. All data from a special purpose monitor (SPM) using an FRM or FEM which has operated for mo re than 24 months is eligible for comparison to the NAAQS unless the monitoring agency demonstrates that the data came from a particular period during which the requirements of appendix A (qualit y assurance requirements) or appendix E (probe and monitoring path siting criteria) were not met.]

The existing Phoenix-Mesa nonattainment area for th e 1997 ozone NAAQS comprises the central portion of Maricopa County and a small portion of n orthern Pinal County (see Map 1a in Appendix 2). The 2010 DVs for the ozone NAAQS for counties in the existing Phoenix-Mesa nonattain ment area are shown in Table 2.

Table 2. Air Quality Data. County State Recommended Nonattainment? 2008-2010 Design Value (parts per billion ) Maricopa, AZ Yes (partial) 77 Pinal, AZ Yes (partial) 74

Ozone monitors relevant for comparison to the NAAQS and information from additional data sources within the existing Phoenix-Mesa nonattainment area and the surrounding area are shown in Appendix 1, Map 1 (also inserted below). Arizona’s ozone se ason encompasses the entire year, but some ozone monitors in the existing Phoenix-Mesa nonattainment area have been approved to operate on a seasonal schedule per 40 CFR part 58, Appendix D, section 4. 1(i). Certified, quality assured data are availabl e in EPA’s Air Quality System (AQS) for all areas throug h calendar year 2010. The Appendix 1 map includes preliminary 2011 DVs for the existing Phoe nix-Mesa nonattainment area for informational purposes only. For each monitor, Appendix 1 lists the monitor, the 2008-2010 DV (certified and qualit y assured in AQS), the preliminary 2009-2011 DV (as a vailable in AQS as of October 31, 2011), and a preliminary 2009-2011 DV using 2011 data from Ozone Watch 3 

## . Absence of a DV is symbolized with an “x”.

3 

### The preliminary 2009-2011 design values indicated by OzoneWatch are based on AQS ozone data from 2009 , 2010, and 2011, supplemented with 2011 data reported to AirNo w ( http://airnow.gov/ ) on days for which no data currently exist in the

### Technical Support Document for the State of Arizona - Page 6 of 19



## Appendix 3 lists the DVs for monitors in the existi ng Phoenix-Mesa nonattainment area. Monitors shown in bold are the DV monitors (i.e., the monito r with the highest DV) for each individual county. Monitors shown in red font are the DV monitor for t he nonattainment area. Values with an asterisk do not meet data completeness, and therefore those DVs are not relevant for comparison to the NAAQS and are solely provided for informational purposes.

AQS database. 2009 and 2010 AQS data were retrieve d on July 20, 2011; 2011 AQS and AirNow data were c ompiled on October 4, 2011. Ultimately, attainment of the 8-h our ozone NAAQS will be determined entirely from da ta in AQS. From Appendix 1, Map 1: For map legend describing m onitors, emissions, traffic, population, and bounda ries, see Appendix 1

### Technical Support Document for the State of Arizona - Page 7 of 19



## Monitors in Maricopa County show a violation of the 2008 8-hour ozone standard based on 2008-2010 data. These violating monitors are located within the portion of Maricopa County that was included as part of the designated nonattainment area for the 1 997 ozone standard. Since the county contains violating monitors, Factor 1 supports including Mar icopa County, in whole or in part, in the intended Phoenix-Mesa nonattainment area. A county (or part ial county) must also be designated nonattainment if it contributes to a violation in a nearby area. Each county without a violating monitor that is lo cated near a county with a violating monitor has been eva luated based on the weight of evidence of the five factors and other relevant information to determine whether it contributes to the nearby violation (se e Factor 2 discussion, below). In addition, we evalu ate those factors to determine whether to include a ll of Maricopa County or just a part within the designate d nonattainment area.



# Factor 2: Emissions and Emissions-Related Data

EPA evaluated emissions of ozone precursors, nitrog en oxides (NO x 

## ) and volatile organic compounds (VOC), and other emissions-related data that provid e information on areas contributing to violating monitors.

Emissions data

EPA evaluated county-level emission data for NO x 

## and VOC derived from the 2008 National Emissions Inventory (NEI), version 1.5. This is the most rec ently available NEI (see http://www.epa.gov/ttn/chief/net/2008inventory.html ). Emissions in a nearby area indicate the potenti al for the area to contribute to observed violations. We will also consider any additional information w e receive on changes to emissions levels that are not reflected in recent inventories. These changes include emissions reductions due to permanent and e nforceable emissions controls that will be in place before final designations are issued and emissions increases due to new sources.

Table 3 shows emissions of NO x 

## and VOC (given in tons per year) for Maricopa and Pinal Counties.

Table 3. Total 2008 NO x 

## and VOC Emissions. County State Recommended Nonattainment? NO x 

## (tpy) VOC (tpy) Maricopa, AZ Yes (partial) 89,020 90,615 Pinal, AZ Yes (partial) 11,668 11,531 Areawide: 100,688 102,146

Maricopa and Pinal Counties, with an area of approx imately 9,200 square miles and 5,366 square miles, respectively, are among the largest counties in the nation, and, aside from the urban core, are compri sed entirely of desert terrain. Emissions of ozone pre cursors shown in Table 2 represent emissions from t he entire counties of Maricopa and Pinal, not just the portions of those counties recommended by the stat e for inclusion in the Phoenix-Mesa nonattainment are a. Emissions of NO x 

## and VOC from Maricopa County are nearly eight times larger than NO x 

## and VOC emissions from Pinal County. Most of the stationary source emissions of ozone precursors are located in the center of the state-recommended nonattainment area (see Map 1 of Appendix 1), with additional stationary sources scattered in the western portion of the state-recommended nonattainm ent area of Maricopa County, and fewer stationary sources in the eastern and northern portions of the state-recommended nonattainment area of Maricopa County. Additional stationary sources are located in the small section of Pinal County that is includ ed in the existing Phoenix-Mesa 1997 ozone nonattainment area. Numerous stationary sources are located in Pinal County outside of EPA’s intended boundary for the Phoenix-Mesa nonattainment area, but are

### Technical Support Document for the State of Arizona - Page 8 of 19



## widely scattered and generally located near roadway s. In 2009, the state recommended expanding the existing ozone nonattainment area in the southwest portion of the area, in order to include the Gila R iver Power Station (see Map 1 of Appendix 1). Additiona lly, the state recommended extending the western boundary of the nonattainment area farther west int o Maricopa County by 5 - 10 miles. This expansion incorporates a small (less than 100 tpy) power plan t. In its updated recommendation submitted to EPA on December 1, 2011, the state continued to recomme nd extending the nonattainment boundary to incorporate these two areas of Maricopa County.

In 2009, the state had also recommended that the ex isting 1997 ozone nonattainment boundary be extended to the southeast to incorporate a larger p ortion of Pinal County. In 2011, the state’s updat ed recommendation excluded this area. Several small (l ess than 15 tpy of NO x 

## or VOC) stationary sources of ozone precursor emissions are located in this ar ea of Pinal County (see Map 1 of Appendix 1). These sources are more widely distributed geographically compared to the small portion of Pinal County that is part of the existing 1997 ozone nonattainment area.

In its February 2009 redesignation request and main tenance plan for the 1997 8-hour ozone NAAQS, the state provided information on the proportion of poi nt source emissions from the entire county of Maricopa County compared to the those from the exis ting (for the 1997 ozone NAAQS) ozone nonattainment area 4 

## . Based on its 2005 periodic emission inventory, t he state determined that the existing ozone nonattainment area, comprised of por tions of Maricopa and Pinal counties, captured the majority of point sources of emissions from Maricop a County – the county that contributes dominantly to total emissions from Maricopa and Pinal counties (see Table 3). For 2005, the existing ozone nonattainment area represented 99% of VOC emissions from Maricopa County, and nearly 87% of NO x 

## emissions from Maricopa County. The state’s recomm endation to expand the Maricopa County portion of the nonattainment area to encompass new sources of ozone precursor emissions to the west and southwest of the existing nonattainment area should continue to ensure that relevant emissions sources are included in the nonattainment area designation.

Population density and degree of urbanization

EPA evaluated the population and vehicle use charac teristics and trends of the area as indicators of t he probable location and magnitude of non-point source emissions. These include ozone-creating emissions from on-road and off-road vehicles and en gines, consumer products, residential fuel combustion, and consumer services. Areas of dense population or commercial development are an indicator of area source and mobile source NO x 

## and VOC emissions, which contribute to ozone formation. Rapid population or growth in vehicle m iles traveled (VMT) (see below) in a county on the urban perimeter signifies increasing integration wi th the core urban area, and indicates that it may b e appropriate to include the area associated with are a source and mobile source emissions as part of the nonattainment area. Table 4 shows the population, population density, and population growth information for Maricopa and Pinal Counties.

4 

### See March 23, 2009 submittal of the 8-hour ozone r edesignation request and maintenance plan for the M aricopa nonattainment area from Patrick Cunningham, Acting Director, ADEQ to Laura Yoshii, Acting Regional Adm inistrator, EPA Region IX.

### Technical Support Document for the State of Arizona - Page 9 of 19



## Table 4. Population and Growth.

County State

Recommended Nonattainment? 2010 Population 2010 Population Density (1000 pop/sq mi) Absolute change

in population (2000-2010) Population %

change (2000-2010) Maricopa, AZ Yes (partial) 3,817,117 0.41 719,617 +23% Pinal, AZ Yes (partial) 375,770 0.07 194,494 +107% Areawide: 4,192,887 0.29 914,111 +28% Sources: U.S. Census Bureau population estimates fo r 2010 as of August 4, 2011 ( http://factfinder2.census.gov/faces/tableservices/j sf/pages/productview.xhtml?pid=DEC_10_PL_GCTPL2.STO 5& prodType=table )



## Population information shown in Table 4 represents all of Maricopa and Pinal Counties, not just the portions of those counties recommended by the state for inclusion in the 2008 ozone Phoenix-Mesa nonattainment area. Similar to the stationary sour ce emissions of ozone precursors, the population of Maricopa County is substantially larger and denser than Pinal County. Although the percent change in population over 2000-2010 in Pinal County was very large (107%), its absolute change in population was still much smaller than Maricopa County’s – les s than a third. The largest population centers are located in Maricopa County (see Map 1a in Appendix 2). The eastern portion of the Phoenix metropolitan area extends into the Apache Junction portion of Pinal County and is included in the existing nonattainment area, as well as the state’s recommended nonattainment area. Aside from the urbanized Phoenix area, the rest of both Maricopa a nd Pinal Counties are sparsely populated. The portion of Pinal County, which was included in the state’s 2009 recommendation but excluded in the 2011 recommendation, contains a few population cent ers, but is generally more sparsely populated compared to Apache Junction, the portion of Pinal C ounty that is part of the existing 1997 ozone nonattainment area.

In its February 2009 redesignation request and main tenance plan for the 1997 8-hour ozone NAAQS, the state also provided information on populations with in the existing 1997 ozone nonattainment area and Maricopa County – the county that contributes domin antly to total emissions from Maricopa and Pinal Counties. Based on 2004 demographic data, the resi dent and non-resident populations within the existing ozone nonattainment area were 100.52% and 109.09% of the resident and non-resident populations of Maricopa County, respectively. Ther efore, in 2004, the population of the existing 1997 ozone nonattainment area (consisting of portions of Maricopa and Pinal Counties) was greater than the population of Maricopa County.

Traffic (VMT) data

EPA evaluated the commuting patterns of residents i n the area, as well as the total VMT for each county. In combination with the population/populat ion density data and the location of main transportation arteries (see above), this informati on helps identify the probable location of non-poin t source emissions. A county with high VMT is general ly an integral part of an urban area and indicates the presence of motor vehicle emissions that may co ntribute to ozone formation and nonattainment in the area. Rapid population or VMT growth in a coun ty on the urban perimeter signifies increasing integration with the core urban area, and indicates that the associated area source and mobile source emissions may be appropriate to include in the nona ttainment area. Table 5 shows total 2008 VMT for Maricopa and Pinal Counties.

### Technical Support Document for the State of Arizona - Page 10 of 19



## Table 5. Traffic (VMT) data

. County State Recommended

Nonattainment? 2008 VMT* (million miles) Maricopa, AZ Yes (partial) 33,393 Pinal, AZ Yes (partial) 3,972 Areawide: 37,365 *MOBILE model VMTs are those inputs into the NEI ve rsion 1.5.



## The total 2008 VMT in Maricopa County was over 8 ti mes higher than the 2008 VMT in Pinal County. The highest non-truck traffic volume occurs within the population centers located in the Maricopa County portion of the nonattainment area, with some heavy traffic on roads that run south, north, and to a lesser extent, west from the population centers ( see Map 1 of Appendix 1).



# Factor 3: Meteorology (weather/transport patterns)

EPA evaluated available meteorological data to help determine how meteorological conditions, such as weather, transport patterns and stagnation conditio ns would affect the fate and transport of precursor emissions contributing to ozone formation.

Maricopa and Pinal Counties lie in a hot desert are a of Arizona, where summer temperatures regularly exceed 100 degrees F. In the absence of the strong winds associated with summer storms that sometimes occur in the area, the high temperatures are conducive to ozone formation. ADEQ has described the basic flow pattern that results in “s loshing” of pollutant towards the west, and then la ter in the day back toward the east:

“The mountain-valley flow defines the daily surface wind patterns in the Phoenix area in the absence of synoptic weather systems with associated cold fronts. As a result, Phoenix has a typical diurnal wind pattern that exists nearly yea r-round due to its geographical position within the valley. ... When the sun rises over the Superst itions in the east, the east-facing mountains in the west valley such as the White Tank Mountains be gin to heat up. As the morning progresses, an energy imbalance is created where the warmer air over the White Tank Mountains rises while the cooler air over the east mountains such as the Superstition mountains sinks. This causes the surface winds across the valley to move from east t o west.... By about 2 p.m., the mountains in the east part of the valley have more direct sunlig ht than the west. This imbalance in energy leads to a shift in surface winds from out of the west du ring the afternoon period. As the sun goes down, equal cooling takes place and winds decrease to nearly calm.” 5



## While the mountains to east and west provide partia l barriers to transport of pollutants in certain directions (especially the northeast), they do not form a closed basin. There is opportunity for emis sions from outside the immediate metropolitan Phoenix are a to contribute to ozone formation. “Wind patterns in Phoenix suggest that ozone and ozone precursors can be transported in the morning from the far west and southern portions of the valley and impact moni tors in the Phoenix valley.” 6 

## In recognition of this, the state recommended extending the boundaries of t he previous ozone nonattainment area. The recommendation included several new point sources t o the west and southwest, as discussed above under Factor 2.

5 

### ADEQ 2009 Recommendations, p.44-45
6 

### ADEQ 2009 Recommendations, p.42

### Technical Support Document for the State of Arizona - Page 11 of 19 Figure 2 Source: ADEQ 2009 Recommendations, p.54 Figure III. 36: “High mountain slopes to the west of Phoenix are heated in the morning and surfa ce air is drawn towards the west.”

Figure 3 Source: ADEQ 2009 Recommendations, p.54 Figure III. 37: “High mountain slopes to the east of Phoenix are heated in the late afternoon an d surface air is drawn towards the east.”


## The west-east flow pattern is generally consistent with the 30-year average of National Weather Servic e summer wind direction frequencies computed by EPA, as shown in the “radar”-style wind rose diagram below (Figure 4).

### Technical Support Document for the State of Arizona 

# Factor 4: Geography/topography

The geography/topography analysis evaluates the phy sical features of the land that might airshed and, therefore, the distribution of ozone o ver the

The Phoenix-Mesa area is partly surrounded by mountains of varying h eights. As described by the state:

“ The Phoenix metropolitan area lies in a valley bord ered by the Superstition Mountains to the east, the New River Mountains to the north a nd northeast, the Hieroglyphic Mountains to the northwest near Lake Pleasant, the White Tank Mountains in the west, the Estrella Mountains to the southwest, and the South Mountains to the south. The Salt River runs through the southern part of the metropo litan area and exits to the southwest with the Gila and Agua Fria Rivers joining it near Goodyear, and the Hassayampa Ri joining west of Palo Verde.” 7



## While the mountains to the east and west provide pa rtial barriers to transport of pollutants in certai n directions (especially the northeast), they do not form a closed basin. There is opportunity for emis sions from out side the immediate metropolitan Phoenix area to con tribute to ozone formation. “ in Phoenix suggest that ozone and ozone precursors can be transported in the morning from the far west and southern portions of the valley and impact moni tors in

7 

### ADEQ 2009 Recommendations, p.44
8 

### ADEQ 2009 Recommendations, p.42



### Technical Support Document for the State of Arizona - Page 12 of 19 

## Figure 4


# Factor 4: Geography/topography (mountain ranges or other air basin boundaries)

The geography/topography analysis evaluates the phy sical features of the land that might airshed and, therefore, the distribution of ozone o ver the area.

area is partly surrounded by mountains of varying h eights. As described by the state:

The Phoenix metropolitan area lies in a valley bord ered by the Superstition Mountains to the east, the New River Mountains to the north a nd northeast, the Hieroglyphic Mountains to the northwest near Lake Pleasant, the White Tank Mountains in the west, Estrella Mountains to the southwest, and the South Mountains to the south. The Salt River runs through the southern part of the metropo litan area and exits to the southwest with the Gila and Agua Fria Rivers joining it near Goodyear, and the Hassayampa Ri
7



## While the mountains to the east and west provide pa rtial barriers to transport of pollutants in certai n directions (especially the northeast), they do not form a closed basin. There is opportunity for emis sions side the immediate metropolitan Phoenix area to con tribute to ozone formation. “ in Phoenix suggest that ozone and ozone precursors can be transported in the morning from the far west and southern portions of the valley and impact moni tors in the Phoenix valley.” 8 

## In recognition of this,

19 

# (mountain ranges or other air basin boundaries)

The geography/topography analysis evaluates the phy sical features of the land that might affect the

area is partly surrounded by mountains of varying h eights. As described by the state:

The Phoenix metropolitan area lies in a valley bord ered by the Superstition Mountains to the east, the New River Mountains to the north a nd northeast, the Hieroglyphic Mountains to the northwest near Lake Pleasant, the White Tank Mountains in the west, Estrella Mountains to the southwest, and the South Mountains to the south. The Salt River runs through the southern part of the metropo litan area and exits to the southwest with the Gila and Agua Fria Rivers joining it near Goodyear, and the Hassayampa Ri ver

While the mountains to the east and west provide pa rtial barriers to transport of pollutants in certai n directions (especially the northeast), they do not form a closed basin. There is opportunity for emis sions side the immediate metropolitan Phoenix area to con tribute to ozone formation. “ Wind patterns in Phoenix suggest that ozone and ozone precursors can be transported in the morning from the far west In recognition of this,

### Technical Support Document for the State of Arizona - Page 13 of 19



## the state recommended a nonattainment area which in corporates source areas that are relatively far fro m central metropolitan Phoenix and the highest ozone concentrations.



# Factor 5: Jurisdictional boundaries

For each potential nonattainment area, we considere d existing jurisdictional boundaries to provide a clearly defined legal boundary and to help identify the areas appropriate for carrying out the air qua lity planning and enforcement functions for nonattainmen t areas. Examples of jurisdictional boundaries include existing/prior nonattainment area boundarie s for ozone or other urban-scale pollutants, county lines, air district boundaries, township boundaries , areas covered by a metropolitan planning organization, state lines, areas of Indian country, and urban growth boundaries. Where existing jurisdictional boundaries were not adequate or appr opriate to describe the nonattainment area, other clearly defined and permanent landmarks or geograph ic coordinates were considered.

The Phoenix-Mesa intended nonattainment area has pr eviously established nonattainment boundaries associated with both the 1-hour and 1997 8-hour ozo ne NAAQS. The boundary of the Phoenix nonattainment area for the 1997 ozone NAAQS include s a large portion of Maricopa County and a small portion of Pinal County (Apache Junction). The sta te has recommended a slightly different boundary for the 2008 ozone NAAQS. The state has requested that EPA expand the boundary of the nonattainment area for the 2008 ozone NAAQS, relati ve to the boundary established for the 1997 ozone NAAQS.

The Phoenix-Mesa-Glendale metropolitan statistical area (MSA) is comprised solely of Maricopa and Pinal Counties. The Phoenix-Mesa-Glendale MSA is n ot part of a combined statistical area (CSA). The majority of the urban area lies mainly in Maricopa County, with a portion of the eastern urbanized are a extending into Pinal County. The Maricopa Associat ion of Governments (MAG), a metropolitan planning organization (MPO), has jurisdiction of bo th air and transportation planning for the metropolitan area. Together, Maricopa and Pinal co unties comprise the Phoenix-Mesa-Glendale Metropolitan Statistical Area. 9 

## The cities of Phoenix, Mesa and Glendale are enti rely contained within Maricopa County. But, as noted above, the urbanize d area extends into Pinal County.

The Maricopa County partial county boundary, for bo th the recommended area and the existing nonattainment area for the 1997 ozone NAAQS, follow s the county boundary to the north, east and southeast (excluding Gila River Indian Community, s ee discussion below, and including a small portion of Pinal County that bounds the eastern edge of the Phoenix-Mesa urbanized area). The boundaries for this area are consistent with MAG’s north, east, an d southeast planning area boundaries. To the west and southwest, the ozone nonattainment area boundar y follows township and range boundaries in a way that encompasses stationary and mobile sources and population centers. MAG defined an “Area A” for air pollution control purposes in the past, mainly associated with dust controls and other restriction s (e.g., no-burn days). Area A became part of the 1- hour ozone as well as the 1997 8-hour ozone nonattainment area. Area A is bounded to the west by township and range boundaries. For the western and southwestern boundaries for the designated Phoe nix-Mesa nonattainment area for the 2008 ozone NAAQS, the state recommended including the entire e xisting area and two expanded areas in the east and south. This includes all of Area A, several to wnship and ranges on the west that were included in prior ozone designations (for 1-hour and the 1997 8 -hour ozone NAAQS), and several newly added

9 

### The Office of Management and Budget names such are as in decreasing ranking of populated areas within the MSA. Phoenix is therefore larger than Mesa, which is lar ger than Glendale.

### Technical Support Document for the State of Arizona - Page 14 of 19



## township and range areas to the west and to the sou thwest. The state recommended these expanded boundaries because there are several large stationa ry sources located in those areas (e.g., power plan ts).

In 2009, the state recommended expanding the Pinal County portion of the existing ozone boundary to encompass a violating monitor and a planned power p lant. However, on December 1, 2011, in an update to its 2009 recommendation, the state revert ed to the existing Pinal partial county boundary, which includes only the Apache Junction portion. T he state explained that more recent air quality monitoring in the formerly recommended area shows t he previously violating monitor is now attaining the standard. In addition, economic conditions put the development of a power plant in the area in doubt.

The Phoenix-Mesa intended nonattainment area also i ncludes an area of Indian country. As defined at 18 U.S.C. 1151, “Indian country” refers to: “(a) al l land within the limits of any Indian reservation under the jurisdiction of the United States Government, n otwithstanding the issuance of any patent, and, including rights-of-way running through the reserva tion, (b) all dependent Indian communities within the borders of the United States whether within the original or subsequently acquired territory thereo f, and whether within or without the limits of a state , and (c) all Indian allotments, the Indian titles to which have not been extinguished, including rights- of-way running through the same.” EPA recognizes the sovereignty of tribal governments, and has atte mpted to take the desires of the tribes into accoun t in establishing appropriate nonattainment area boundar ies.


# Evaluation of Recommendation from Gila River Indian Community

Pursuant to section 107(d) of the Clean Air Act, EP A must designate as nonattainment those areas that violate the NAAQS and those areas that c ontribute to violations. EPA has evaluated the recommendation of the Gila River Indian Communi ty (Gila River) based on currently available information.

In 1999, 2000, and 2003, Gila River recommended tha t their reservation lands in Maricopa and Pinal Counties be designated as “unclassifiable” fo r the 1997 ozone NAAQS (letter from Mary Thomas, Governor, Gila River Indian Community, to F elicia Marcus, Regional Administrator, U.S. EPA Region IX, September 2, 1999; Letter from Donald Antone, Governor, Gila River Indian Community, to Felicia Marcus, Regional Admin istrator, U.S. EPA Region IX, October 31, 2001; Letter from Richard Narcia, Governor, Gil a River Indian Community, to Wayne Nastri, Regional Administrator, U.S. EPA Region IX, July 3, 2003).

In 2003, EPA indicated that we agreed with the Gila River’s recommendations and intended to designate the geographic area covered in those reco mmendations as attainment/unclassifiable (letter from Wayne Nastri, Regional Administrator, U.S. EPA Region IX, to Richard Narcia, Governor, Gila River Indian Community, December 3, 2003).

In 2004, EPA established the Phoenix-Mesa nonattain ment area boundaries for the 1997 ozone NAAQS that excluded the portions of Maricopa and Pi nal Counties that encompass the Gila River.

In March 2009, Gila River again recommended that po rtions of Gila River in Maricopa and Pinal Counties be designated as “attainment” for the 2008 ozone NAAQS (letter from William Rhodes, Governor, Gila River Indian Community, to L aura Yoshii, Acting Regional Administrator, U.S. EPA Region IX, March 11, 2009).

### Technical Support Document for the State of Arizona - Page 15 of 19



## Gila River is a federally recognized tribe with res ervation lands in Maricopa and Pinal Counties. The majority of the tribal land is located in Pinal County and has not been subject to urbanization and is mainly a rural environment with two main pop ulation centers in St. Johns and Sacaton and over 35,000 acres of agricultural lands. Gila Rive r has an on-reservation population of approximately 22, 000 people. These population cen ters are not integrated within the Phoenix metropolitan area and pale in comparison to the 3,8 00,000 people living in the adjacent Maricopa County. Also, The South Mountains to the north and the Estrella mountains in the west may provide some geographical and topographic barriers between the Phoenix-Mesa nonattainment area and the majority of Gila River reservation lan ds. These areas of Indian country and the adjacent proposed Phoenix-Mesa nonattainment areas are shown in Map 1a in Appendix 2.

Currently, Gila River operates a network of two ozo ne monitors within the tribal boundaries that represent both the northwestern and the central por tions of the Gila River lands. The map in Appendix 1 shows monitor locations for the Phoenix- Mesa nonattainment area, including Gila River monitors. EPA anticipates relying on 2008-201 0 data to designate this area. Appendix 1 provides preliminary 2011 data for informational pu rposes only. Based on the information currently available, both monitors operated by Gila River in their area of Indian country indicate that the area is attaining the 2008 ozone NAAQS for 2008-2010.

Based on the low population, the largely rural envi ronment, the presence of some topographical barriers, and air quality data, EPA continues to ag ree that that the Gila River areas of Indian country have different ozone concentrations than su rrounding areas and are not affected by the poor air quality present in the Phoenix-Mesa nonatt ainment area. Therefore, the portions of Gila River lands located in Maricopa and Pinal Counties should be excluded from the Phoenix-Mesa nonattainment area and designated unclassifiable/at tainment, consistent with the designation of the adjacent areas in Pinal County.


# Evaluation of Recommendation from Tohono O’odham Na tion of Arizona

Pursuant to section 107(d) of the Clean Air Act, EP A must designate as nonattainment those areas that violate the NAAQS and those areas that c ontribute to violations. EPA has evaluated the recommendation of the Tohono O'odham Nation of Arizona (Tohono O’odham) based on currently available information.

In 2004, EPA established the Phoenix-Mesa nonattain ment area boundaries for the 1997 ozone NAAQS. This nonattainment area did not include por tions of Maricopa County that encompass non-contiguous reservation lands of Tohono O’odham.

In March 2009, Tohono O’odham recommended that the portions of Tohono O’odham in Maricopa, Pinal, and Pima Counties be designated as “attainment/unclassifiable” for the 2008 ozone NAAQS (letter from Ned Norris, Chairman, Toho no O’odham Nation, to Laura Yoshii, Acting Regional Administrator, U.S. EPA Region IX, March 11, 2009).

Tohono O'odham is a federally recognized tribe with non-contiguous reservation land in Maricopa, Pinal, and Pima Counties. These areas of Indian country and the surrounding proposed nonattainment areas are shown on Map 1a in Appendix 2. The majority of the Tribe’s reservation lands are located in Pinal and Pima cou nties, outside of the intended Phoenix-Mesa nonattainment area. However, some areas of Indian country taken into trust by the U.S.

### Technical Support Document for the State of Arizona - Page 16 of 19



## Department of Interior for the Tribe in 2010 are lo cated near Glendale, Arizona, which is about nine miles northwest of downtown Phoenix and near t he center of the intended Phoenix-Mesa nonattainment area 10 

## . There are no geographic or topographical barrier s that preclude air pollution transport from the surrounding intended P hoenix-Mesa nonattainment area. Based upon currently available information, it appears th at these areas of Indian country are affected by the poor air quality that exists within the intende d Phoenix-Mesa nonattainment area. Therefore, while the Tribe has recommended “attainment/unclass ifiable” for all areas of Indian country, EPA intends to include the portions of Tohono O'odh am lands located in Maricopa County (specifically, areas of Indian country located nearGlendale, Arizona) as part of the PhoenixMesa nonattainment area. The remaining lands locat ed in Pinal and Pima Counties are not contiguous and EPA intends to designate these lands as unclassifiable/attainment, consistent with the designation of the surrounding area.


# Evaluation of Recommendation from Salt River Pima-M aricopa Indian Community

Pursuant to section 107(d) of the Clean Air Act, EP A must designate as nonattainment those areas that violate the NAAQS and those areas that c ontribute to violations. EPA has evaluated the recommendation of the Salt River Pima-Maricopa Indian Community (Salt River) based on currently available information.

In 2004, EPA established the Phoenix-Mesa nonattain ment area boundaries for the 1997 ozone NAAQS that included portions of Maricopa County tha t encompass Salt River.

In March 2009, the Salt River Pima-Maricopa Indian Community recommended that portions of Salt River in Maricopa County be designated as “att ainment/unclassifiable” for the 2008 ozone NAAQS (letter from Martin Harvier, Vice President, Salt River Pima-Maricopa Indian Community, to Laura Yoshii, Acting Regional Adminis trator, U.S. EPA Region IX, March 9, 2009). Based on the factors discussed below, EPA h as preliminarily concluded that Salt River lands should be designated nonattainment as part of the Phoenix-Mesa nonattainment area for the 2008 ozone NAAQS.

Air Quality Data

Currently, Salt River operates a network of four oz one monitors within the tribal boundaries. Map 1 in Appendix 1 shows monitor locations for the Phoenix-Mesa nonattainment area, including Salt River monitors. For each monitor, A ppendix 1 lists the monitor, the 2008-2010 design value (DV), the preliminary 2009-2011 DV (as available in AQS as of October 31, 2011), and a preliminary 2009-2011 DV using 2011 data from OzoneWatch. 11 

## Values with an asterisk do not meet data completeness, and therefore those DVs are not relevant for comparison to the

10 

### On June 23, 2010 the U.S. Department of Interior ( DOI) approved a request from the Tohono O'odham Nat ion to take 53.54 acres of land held in fee by the Tribe and lo cated in Maricopa County, AZ near Glendale, into tr ust (75 FR 21130). DOI made this approval pursuant to the Gila Bend Indian Reservation Lands Replacement Act, P.L. 99-503, Stat 100 1798 (1986), Section 6(d) , which mandates the following: "Any land which th e Department of Interior holds in trust for the Tri be shall be deemed to be a Federal Indian Reservation for all purposes." EPA is designating this trust l and along with the surrounding Phoenix nonattainment area. EPA notes t hat it is not making any determination on the Tribe 's Reservation boundary through this designation process.
11 

### The preliminary 2009-2011 design values indicated by OzoneWatch are based on AQS ozone data from 2009 , 2010, and 2011, supplemented with 2011 data reported to AirNo w ( http://airnow.gov/ ) on days for which no data currently exist in the AQS database. 2009 and 2010 AQS data were retrieve d on July 20, 2011; 2011 AQS and AirNow data were c ompiled on October 4, 2011. Ultimately, attainment of the 8-h our ozone NAAQS will be determined entirely from da ta in AQS.

### Technical Support Document for the State of Arizona - Page 17 of 19



## NAAQS and are solely provided for informational pur poses. Absence of a DV is indicated with an “x.” EPA plans to designate Arizona for the 2008 ozone NAAQS using certified 2008-2010 DV data; preliminary 2011 data are provided for inf ormational purposes.

Based on the information currently available, the R ed Mountain ozone monitor (AQS ID: TT6157021; see Appendix 3) operated by Salt River o n tribal lands has a 2008-2010 8-hour design value of 0.076 ppm, which constitutes a viol ation of the 2008 ozone NAAQS.

Emissions and Emissions-Related Data

Salt River consists of 54,000 acres of reservation lands, which is home to over 10,000 tribal members. Salt River has some emissions sources wit hin the tribal boundaries, including aggregate mining facilities, asphalt and concrete b atch plants, and landfills. Also, two major roadways, the Pima Loop 101 (Highway 101- Pima Free way) and the Beeline Highway (Arizona Highway 87), pass through Salt River.

General information on emissions, population densit y and degree of urbanization, traffic and commuting patterns for the Phoenix-Mesa nonattainme nt area can be found in the general intended Phoenix-Mesa nonattainment area Factor 2 d iscussion above and is applicable to Salt River. We do not have independent information sole ly for the Salt River reservation lands.

Meteorology (Weather/Transport Patterns)

Salt River is fairly integrated within the surround ing urban area and therefore the information for the intended Phoenix-Mesa nonattainment area discus sed in Factor 3 also characterizes the meteorology and transport patterns for Salt River.

Geography/Topography

Salt River area does not have any geographical or t opographical barriers that would prevent air pollution transport from the surrounding intended P hoenix-Mesa nonattainment area. Therefore, geography and topography support including Salt Riv er with the surrounding area.

Jurisdictional Boundaries

Salt River is a federally recognized tribe located in the eastern portion of the Phoenix metropolitan area. Map 1a shows the locations and boundaries of Indian country within the intended Phoenix-Mesa nonattainment area.

Conclusion for Salt River

While Salt River has recommended an attainment/uncl assifiable designation, based on the information currently available and the five factor analysis above, including information concerning a violating monitor on reservation lands , EPA has preliminarily concluded that Salt River should be designated nonattainment as part of the Phoenix-Mesa nonattainment area for the 2008 ozone NAAQS.

### Technical Support Document for the State of Arizona - Page 18 of 19 

# Conclusion

Based on the assessment of factors described above, EPA has preliminarily concluded that the following counties and areas of Indian country should be incl uded as part of the Phoenix-Mesa nonattainment area because they are either violating the 2008 ozone NA AQS or contributing to a violation in a nearby area : Maricopa County (partial), Pinal County (partial), the Salt River-Pima Maricopa Indian Community, and the Tohono O’odham Nation of Arizona (partial).

Based on 2008-2010 DV data (Factor 1), Maricopa Cou nty contains two violating monitors and Pinal County does not contain any violating monitors. Con sideration of only air quality data and the locatio n of violating monitors indicates that all or part of Maricopa County should be included in the 2008 8-h our ozone nonattainment area.

Emissions of ozone precursors (Factor 2) from Maric opa County are over ten times larger than from Pinal County. The state’s partial boundary recomme ndations for Maricopa and Pinal Counties include the dense population centers and roadways, as well as the majority of the stationary sources of ozone precursor emissions in Maricopa and Pinal Counties. Maricopa and Pinal Counties are geographically large. Outside of the densely populated urban Phoe nix core, these counties are sparsely populated wit h relatively few stationary and mobile sources of ozo ne precursor emissions. The distribution of stationary and mobile emission sources (Factor 2) a nd information provided by the state in its redesignation request and maintenance plan for the 1997 8-hour ozone NAAQS – indicating that the majority of emissions in Maricopa County are well r epresented by the 1997 ozone nonattainment area – supports the state’s recommendation to use the exis ting 1997 8-hour ozone nonattainment boundary while also expanding the boundaries in Maricopa Cou nty to encompass additional stationary sources located to the west and southwest. Because Pinal C ounty contributes a small fraction to total ozone precursor emissions from Maricopa and Pinal Countie s, and because stationary and mobile sources in Pinal County, outside the state-recommended nonatta inment area, are widely distributed throughout the large county area, Factor 2 supports the state’s re commendation to maintain the existing 1997 8-hour ozone nonattainment boundary around the Apache Junc tion area.

Meteorology and weather or transport patterns (Fact or 3) and geography and topography (Factor 4) show that there is the potential for some contribut ion to ozone violations from emissions occurring toward the southeast, in Pinal County. In consider ing jurisdictional boundaries (Factor 5), EPA notes that the state’s recommended nonattainment area bou ndaries expands the Maricopa County portion of the nonattainment area, but is otherwise consistent with the 1997 8-hour ozone nonattainment area.

Based on our analysis of all five factors, EPA supp orts the state’s recommendation for the nonattainme nt area boundary in Maricopa and Pinal Counties.

Three tribes located within or near the boundaries of the Phoenix-Mesa intended nonattainment area submitted recommendations to EPA. EPA has prelimin arily concluded that the portions of Gila River located in Maricopa and Pinal counties should be ex cluded from the intended Phoenix-Mesa nonattainment area and designated unclassifiable/at tainment based on air quality data, the low population, the largely rural environment, and the presence of some topographical barriers. Based upo n currently available information, it appears that th e portions of Tohono O'odham located in Maricopa County are affected by the poor air quality. There fore, EPA has preliminarily concluded that the portions of Tohono O'odham located in Maricopa Coun ty (specifically, areas of Indian country located in Glendale, Arizona) should be included as part of the intended Phoenix-Mesa nonattainment area. Because the remaining portions of Tohono O’odham ar e non-contiguous and are not located within

### Technical Support Document for the State of Arizona - Page 19 of 19



## EPA’s intended nonattainment area for the 2008 ozon e NAAQS, EPA intends to designate the portions of Tohono O’odham located in Pinal and Pima Countie s as unclassifiable/attainment consistent with the surrounding areas. EPA has also preliminarily conc luded that Salt River should be designated nonattainment as part of the intended Phoenix-Mesa nonattainment area for the 2008 ozone NAAQS, due to a violating monitor on tribal lands and cons ideration of other factors discussed above.

Based on our consideration of all five factors, EPA has preliminarily concluded that Maricopa (partial ) and Pinal (partial) Counties in Arizona and areas o f Indian country – Salt River and Tohono O’odham (partial) – should be designated nonattainment forthe 2008 ozone NAAQS as the Phoenix-Mesa multijurisdictional nonattainment area.

### A p p e n d i x 1:

M a p s h o w i n g M o n it o r s , E m i s s i o n s , V e h i c l e T r a ff i c , a n d G e n e r a l P o pu l a ti onS a n D i e g o 2 00 8

- 2 0 1 0 A Q S de s i gn v a l ue
2 00 9

- 20 1 1 A Q S de s i gn v a l ue 20 0 9

- 2 0 1 1 O z on e W a t c h d e s i g n v a l ue

* D e s i gn v a l u e i n v a l i d du e t o d a t a c o m p l e t e n e s s i ss u e s. D e s i gn V a l u e s a r

e l a b e l e d w i t h 2 0 1 0 A Q S
, 2 0 1 1 A Q S
, a nd 20 1 1 O z o n e W a t c h d e s i gn v a l u e s , r e s p e c t i v e l y. A b s e n c e o f d e s i gn v a l u e s y m bo l i z e d w i t h a n " x ". S o u r c e s : U S E P A ' s A Q S d a t a b a s e ( 1 0 / 3 1 / 1 1 )

, U S E P A ' s N E I ( 200 8 ), O z o n e W a t c h ( 1 0 / 4 / 1 1 )

, U S C e n s u s ( 2 0 1 0 )

, ES R I ( 2 0 1 1 )

, T A N A ( 2 0 0 6 )

, F T

A ( 2 0 0 7 ).
1 M o n i t o r

s a r e c o l o r

- c o d e d b a s e d o n t h e h i g h e s t 2 0 0 9

- 2 0 1 1 d e s i g n v a l ue b e t w e en A Q S o r O z o n e W a t c h.
2 A r e a s o f I n d i an c o un t r y d i s p l a y e d h e r e a r e i n t e nd e d f o r i l l u s t r a t i v e p u r p o s e s o n l y. E PA d o e s n o t h a v e t h e a u t h o r i t y t o d e f i ne o f f i c i a l b o u nda r i e s f o r a r e a s o f I n d i an c o u n t r y. H e n c e , E PA doe s no t g u a r a n t e e t he a c c u r a cy o r c o m p l e t e n e ss o f I n d i a n c o u n t r y b o u n d a r i e s d i s p l a y e d i n t h i s m a p. AI R 1 20 0 0 0 9

_ l e ge n d

. m xd N o v e m b e r 3 0

, 2 0 11 

# L e g e nd

20 0 8 N E I NO x a nd V O C P o i n t S ou r c e E m i s s i on s ( T on s p e r y e a r)

< 1 0 0 t on s p e r y e ar

10 0

- 2 49

25 0

- 4 99

50 0

- 1 , 9 99

> 2 , 0 00

E x i s t i ng / E P A

- R e c o m m e nd e d 8

- H ou r O z on e N o n a t t a i n m e n t A r ea

C oun t y B o un d a ry

A nnu a l A

v e r a g e D a i l y N on - T r u c k T r a f f i c ( V o l u m e / d a y)

< 2 5 , 0 00

25 , 0 0 0

- 5 0 , 0 00

50 , 0 0 1

- 1 0 0 , 0 00

10 0 , 0 0 1

- 2 50 , 0 00

> 2 5 0 , 0 00

A nnu a l A

v e r a g e D a i l y T r u c k T r a f f i c ( V o l u m e / d a y)

0

- 1 , 0 00

1 , 00 1

- 5 , 0 00

5 , 00 1

- 1 0 , 0 00

10 , 0 0 1

- 2 5 , 0 00

> 2 5 , 0 00 2 010 C e n s u s C B SA

A i r B a s in

U r b a n A r ea

U r b a n A r ea

M i no r C i v i l D i v i s i on

T o w n s h i p a nd R a nge

M i li t a r y L a nds

N a t i on a l Fo r e s t S e r

v i c e L a nds

N a t i on a l P a r k S e r

v i c e L a n ds

20 1 0 C e n s u s T r a c t P opu l a t i on D e n s i ty

1 00

- 4 99 p e op l e p e r s qu a r e m i le

5 00

- 1 , 9 99

2 , 0 0 0

- 3 , 4 99

3 , 5 0 0

- 4 , 9 99

> 5 , 0 00

S t a t e bound a ry

E l e v a t i on > 1 4 , 0 0 0 ft
1 2 , 0 00
1 0 , 0 00
8 , 0 00
6 , 0 00
4 , 0 00
2 , 0 00

~ M SL E x i s t i ng 19 9 7 O z on e N AA Q S a nd / o r E P A

- I n t e nd ed 2 00 8 O z o n e N AA Q S N o n a tt a i n m e n t A r ea N e w E P A R e c o m m e nd a t i on f o r A t t a i n m e n t f

o r a r e as
c u r r e n t l y d e s i gn a t e d N on a t t a i n m e n t f o r t h e 1 9 97 O z o n e N AA QS

S m i t h R i v e r R a n c h e r ia S a n J o a qu i n V a l l ey

F r es no , CA M e t r o A r ea

MO J A V E D E S E R T A I R B A S IN 88 , 7 4 *
, x

88 , 7 4 *
, x A i r D i s t r i c t / A u t ho r i ty ! ( V i o l a t i ng 8

- H ou r O z on e M on i t o r w i t h 2 0 0 9

- 2 0 1 1 d e s i gn va l ue 1

! ( A tt a i n i ng 8

- H ou r O z o n e M on i t o r w i t h 2 0 0 9

- 20 1 1 d e s i gn va l ue 1

T r i b a l L a nds 2! (

! ( ! (

! ( ! (

! ( ! ( ! (

! ( ! ( ! ( ! (

! ( ! ( !

( ! ( !

(

! ( !

( ! (

!

( !

(

! ( !

( ! ( !

( ! (

! (

! ( ! (

! ( ! ( !

( ! (

!

(

R o c k S o li d p l a n t (N O x : 1 3

. 9 t py ) G a n t z e l F a r m s ( V O C : 9

. 9 t p y) C o n e c o ( N O x : 8

. 6 t p y) A r m y H e l i po r

t ( V O C : 0

. 2 t p y) Q u e e n C r e ek P l a n t ( N O x : 4

. 3 t p y) Q u e e n C r e ek P l a n t # 2 (N O x : 0

. 1 t py )

G i l a R i v e r P o w e r

S t a t i on N O x : 3 4 2

. 9 t py V O C: 6 1

. 1 t py

C a lP or t l a n d C e m e nt N O x : 2 , 0 8 6

. 7 t py V O C: 5

. 2 t py T ohono O ' o dh am N a t i on 73 , 7 1 *
, 72

Gi la R i v er Fo r t M c D o w e ll Y a vapa i N a t i on

S a l t R i v er Y a v a p a i

- P r es c o tt

T on to A p a c he

M a r i c opa ( A k C h i n)

T ohono O ' o dh am N a t i on T ohono O ' odh am N a t i on T

ohono O ' o dh am N a t i on P ho e n i x -M e sa N o n a tt a i n m e n t A r ea

6 4 , 63 *
, 63

6 4 , 6 3 , x 65 , 6 2 * , x 65 , 6 3 *
, x 6 6 *
, 6 6 *
, x

67 , 6 6 *
, x 68 , 6 8 *
, 70 69 , 6 9 *
, 69

69 , 6 8 , x 69 , 6 8 *
, x 7 0 , 68 *
, 68

70 , 7 2 *
, 72

7 0 , 69 *
, x 7 0 , 7 0 *
, x 71 , 6 7 *
, 68 71 , 7 0 *
, 71 71 , 7 1 *
, 71

72 , 7 1 *
, 72 72 , 7 1 *
, 72 7 2 , 7 2 *
, 72

72 , 7 2 *
, 72 72 , 7 3 *
, 73

73 , 7 2 *
, 72 7 3 , 72 *
, 72

7 3 , 72 *
, 73 73 , 7 4 *
, 74 7 3 , 72 *
, x

74 , 7 3 *
, 73

7 4 , 7 3 *
, 74 74 , 7 3 *
, 75

74 , 7 2 * , x 75 , 7 4 *
, 74 7 6 , 7 5 *
, 76

7 7 , 75 *
, 77



# M a p 1 V e r d e

P r e s c o tt

P a y s on

F l o r e n ce

C a sa G r a n de E l oy E x p a nd ed P o r t i on of M a r i c op a C o u n ty E x p a nd ed P o r t i on of M a r i c o p a C o u n ty

* D e s i g n va l u e i n v a l i d d u e t o d a t a c o m p l e t e n e s s i s s u e s. D es i gn V a l u e s a r e l a b e l e d w i t h 2 0 1 0 A Q S, 2011 A Q S
, a nd 20 1 1 O z o n e W

a t c h d e s i gn v a l u e s , r es p e c t i v e l y. A b s e n ce o f d e s i g n v a l u e s y m b o l i z e d w i t h a n " x ". S o u r c e s : U S E P

A ' s A Q S d a t a ba s e ( 1 0 / 3 1 / 1 1 ), O z o n e W a t c h ( 1 0 / 4 / 1 1 )

, U S C e n s u s ( 2 0 10 )

, N E I ( 2 0 08 ), E S R I ( 2 0 1 1 )

, T

A N A ( 2 0 0 6 ). A I R 12 0 0 0 0 9

_ 1

. m xd N o v e m b e r 2 9

, 20 11 

# Ü

0 1 0 20 5 M i l es 2 009

- S t a t e r e c o m m e nd e d no n a tt a i n m e n t; 2 0 1 1

- S t a t e r ec o mm e nd e d un c l a ss i f i a b l e o r a t t a i n m e nt

### A p p e n d i x 2:

M a p s h o wi n g J u r i s d i c ti on a l B o u nd a r i e s a n d D e t a il e d P o p u l a ti onS a n D i e g o 2 00 8

- 2 0 1 0 A Q S de s i gn v a l ue
2 00 9

- 20 1 1 A Q S de s i gn v a l ue 20 0 9

- 2 0 1 1 O z on e W a t c h d e s i g n v a l ue

* D e s i gn v a l u e i n v a l i d du e t o d a t a c o m p l e t e n e s s i ss u e s. D e s i gn V a l u e s a r

e l a b e l e d w i t h 2 0 1 0 A Q S
, 2 0 1 1 A Q S
, a nd 20 1 1 O z o n e W a t c h d e s i gn v a l u e s , r e s p e c t i v e l y. A b s e n c e o f d e s i gn v a l u e s y m bo l i z e d w i t h a n " x ". S o u r c e s : U S E P A ' s A Q S d a t a b a s e ( 1 0 / 3 1 / 1 1 )

, U S E P A ' s N E I ( 200 8 ), O z o n e W a t c h ( 1 0 / 4 / 1 1 )

, U S C e n s u s ( 2 0 1 0 )

, ES R I ( 2 0 1 1 )

, T A N A ( 2 0 0 6 )

, F T

A ( 2 0 0 7 ).
1 M o n i t o r

s a r e c o l o r

- c o d e d b a s e d o n t h e h i g h e s t 2 0 0 9

- 2 0 1 1 d e s i g n v a l ue b e t w e en A Q S o r O z o n e W a t c h.
2 A r e a s o f I n d i an c o un t r y d i s p l a y e d h e r e a r e i n t e nd e d f o r i l l u s t r a t i v e p u r p o s e s o n l y. E PA d o e s n o t h a v e t h e a u t h o r i t y t o d e f i ne o f f i c i a l b o u nda r i e s f o r a r e a s o f I n d i an c o u n t r y. H e n c e , E PA doe s no t g u a r a n t e e t he a c c u r a cy o r c o m p l e t e n e ss o f I n d i a n c o u n t r y b o u n d a r i e s d i s p l a y e d i n t h i s m a p. AI R 1 20 0 0 0 9

_ l e ge n d

. m xd N o v e m b e r 3 0

, 2 0 11 

# L e g e nd

20 0 8 N E I NO x a nd V O C P o i n t S ou r c e E m i s s i on s ( T on s p e r y e a r)

< 1 0 0 t on s p e r y e ar

10 0

- 2 49

25 0

- 4 99

50 0

- 1 , 9 99

> 2 , 0 00

E x i s t i ng / E P A

- R e c o m m e nd e d 8

- H ou r O z on e N o n a t t a i n m e n t A r ea

C oun t y B o un d a ry

A nnu a l A

v e r a g e D a i l y N on - T r u c k T r a f f i c ( V o l u m e / d a y)

< 2 5 , 0 00

25 , 0 0 0

- 5 0 , 0 00

50 , 0 0 1

- 1 0 0 , 0 00

10 0 , 0 0 1

- 2 50 , 0 00

> 2 5 0 , 0 00

A nnu a l A

v e r a g e D a i l y T r u c k T r a f f i c ( V o l u m e / d a y)

0

- 1 , 0 00

1 , 00 1

- 5 , 0 00

5 , 00 1

- 1 0 , 0 00

10 , 0 0 1

- 2 5 , 0 00

> 2 5 , 0 00 2 010 C e n s u s C B SA

A i r B a s in

U r b a n A r ea

U r b a n A r ea

M i no r C i v i l D i v i s i on

T o w n s h i p a nd R a nge

M i li t a r y L a nds

N a t i on a l Fo r e s t S e r

v i c e L a nds

N a t i on a l P a r k S e r

v i c e L a n ds

20 1 0 C e n s u s T r a c t P opu l a t i on D e n s i ty

1 00

- 4 99 p e op l e p e r s qu a r e m i le

5 00

- 1 , 9 99

2 , 0 0 0

- 3 , 4 99

3 , 5 0 0

- 4 , 9 99

> 5 , 0 00

S t a t e bound a ry

E l e v a t i on > 1 4 , 0 0 0 ft
1 2 , 0 00
1 0 , 0 00
8 , 0 00
6 , 0 00
4 , 0 00
2 , 0 00

~ M SL E x i s t i ng 19 9 7 O z on e N AA Q S a nd / o r E P A

- I n t e nd ed 2 00 8 O z o n e N AA Q S N o n a tt a i n m e n t A r ea N e w E P A R e c o m m e nd a t i on f o r A t t a i n m e n t f

o r a r e as
c u r r e n t l y d e s i gn a t e d N on a t t a i n m e n t f o r t h e 1 9 97 O z o n e N AA QS

S m i t h R i v e r R a n c h e r ia S a n J o a qu i n V a l l ey

F r es no , CA M e t r o A r ea

MO J A V E D E S E R T A I R B A S IN 88 , 7 4 *
, x

88 , 7 4 *
, x A i r D i s t r i c t / A u t ho r i ty ! ( V i o l a t i ng 8

- H ou r O z on e M on i t o r w i t h 2 0 0 9

- 2 0 1 1 d e s i gn va l ue 1

! ( A tt a i n i ng 8

- H ou r O z o n e M on i t o r w i t h 2 0 0 9

- 20 1 1 d e s i gn va l ue 1

T r i b a l L a nds 2T ohono O ' o dh am N a t i on T ohono O ' o dh am N a t i on Gi la R i v er Fo r t M c D o w e ll Y a vapa i N a t i on

S a l t R i v er Y a v a p a i

- P r es c o tt

T on to A p a c he

M a r i c opa ( A k C h i n)

T ohono O ' o dh am N a t i on T ohono O ' odh am N a t i on T

ohono O ' o dh am N a t i on P ho e n i x -M e sa N o n a tt a i n m e n t A r ea



# M a p 1a P ho e n i x -M e s a - G l e nd a l e , AZ

M e t r o A r ea

T u c s on , AZ M e t r o A r ea P r e s c o t t , AZ

M e t ro A r ea

P a y s on , AZ M i c r o A r

ea F l a g s t a f f, A Z M e t r o A r ea

E x p a nd ed P o r t i on of M a r i c op a C o u n ty E x p a nd ed P o r t i on of M a r i c o p a C o u n ty A D EQ

M A R I C O PA

P I MA P I N AL

S o u r c e s : U S C e n s u s ( 2 0 10 ), E S R I ( 2 0 1 1 )

, T

A N A ( 2 0 0 6 ). A I R 12 0 0 0 09

_ 1 a

. m xd N o v e m b e r 2 9

, 20 11 

# Ü

0 1 0 20 5 M i l es 20 0 9

- S t a t e r e c o m m e nd e d non a t t a i n m e n t; 20 1 1

- S t a t e r e c o m m e nd e d u n c l a s s i f i a b l e o r a t t a i n m e nt

### A p p e n d i x 3:

Ai r Q u a lit y M o n it o r i n g D a t a T a b le