# Pinal County Air Quality Control District

2009 Ambient Monitoring Network Plan And 2008 Data Summary

June 30, 2009 - Final Pinal County Air Quality

31 N. Pinal St., Bldg. F P.O. Box 987 Florence AZ, 85232 (520) 866-6929 www.pinalcountyaz.gov

### 2

# Table of Contents

1.0 NATIONAL AMBIENT AIR QUALITY STANDARDS (NAAQS) 13 2.0 MONITORING OBJECTIVES AND SPATIAL SCALES 17 3.0 NETWORK DESIGN AND MEASUREMENT QUALITY 21 3.1 NETWORK DESIGN 21 3.2 AQS REQUIREMENTS 22 3.3 MINIMUM NETWORK REQUIREMENTS 22 3.4 MINIMUM SAMPLE FREQUENCY 24 3.5 MEASUREMENT QUALITY CHECKS 25 3.6 OZONE SEASON DEFINITION 25 3.7 QUALITY SYSTEM REQUIREMENTS 27 3.8 LEAD MONITORING NETWOR K DESCRIPTION 27 4.0 MONITORING SITE DESCRIPTIONS 29 4.1 APACHE JUNCTION FIRE STATION 29 4.2 APACHE JUNCTION MAINTENANCE YARD 29 4.3 CASA GRANDE AIRPORT 30 4.4 CASA GRANDE DOWNTOWN 31 4.5 COMBS SCHOOL 31 4.6 COOLIDGE MAINTENANCE YARD 31 4.7 COWTOWN 32 4.8 ELOY COUNTY COMPLEX 34 4.9 MAMMOTH COUNTY COMPLEX 34 4.10 MARICOPA COUNTY COMPLEX (CITY OF MARICOPA) 34 4.11 PINAL AIR PARK 35 4.12 PINAL COUNTY HOUSING COMPLEX 35 4.13 RIVERSIDE MAINTENANCE YARD 36 4.14 STANFIELD COUNTY COMPLEX 36 4.15 QUEEN VALLEY 37 5.0 PROPOSED CHANGES TO THE NETWORK 39 5.1 GILA RIVER BASIN 39 5.2 CASA GRANDE DOWNTOWN PM 2.5 

### 39 5.3 PINAL COUNTY HOUSING RELOCATION 39 5.4 MEDIUM VOLUME PRECISION MEASUREMENT 39 6.0 DATA TRENDS 41 6.1 CARBON MONOXIDE 42 6.2 OZONE 43 6.2.1 ONE-HOUR OZONE 44 6.2.2 EIGHT-HOUR OZONE 45 6.3 PARTICULATE MATTER SMALLER THAN 10 MICRONS (PM 10 

### ) 46 6.3.1 24-HOUR PM 10 

### TRENDS 48 6.3.2 ANNUAL PM 10 

### TRENDS 50 6.4 PARTICULATE MATTER SMAL LER THAN 2.5 MICRONS (PM 2.5 

### ) 53 6.4.1 PM 2.5 

### 24-HOUR TRENDS 54 6.4.2 PM 2.5 

### ANNUAL TRENDS 55

### 6

### 7 

# Appendices

APPENDIX A: ABBREVIATIONS 57

APPENDIX B: PCAQCD SITE DESCRIPTIONS 61

APPENDIX C: PCAQCD AMBIEN T AIR MONITORING DATA 81

APPENDIX D: PUBLIC COMMENTS 99

### 8

### 9 

# Introduction

This document provides two distinct products: 1) a description of the Pinal County Air Quality monitoring system in the form of an Annual Mon itoring Network Plan, and 2) a summary of data obtained from the network.

40 Code of Federal Regulations (CFR) Part 58.10 requires an annual monitoring network plan to summarize the air quality surveillance system c onsisting of State and Local Air Monitoring Stations (SLAMS) and Special Purpose Monitors (SPM) operated under state and local authority. According to the regulation, the Annual Monitoring Network Plan must be submitted to the Regional Administrator by July 1 each year.

The annual monitoring network plan must identi fy the purpose of each monitor and provide evidence that both the siting and the operation of each monitor meet the requirements in 40 CFR Part 58 appendices A, C, D, and E below:

• Appendix A – Quality Assurance Requirements for SLAMS, SPMs, and PSD (Prevention of Significant Deteriorat ion) Air Monitoring

• Appendix C – Ambient Air Qu ality Monitoring Methodology

• Appendix D – Network Design Criteria for Ambient Air Quality Monitoring

• Appendix E – Probe and Monitoring Path Siting Criteria for Ambient Air Quality Monitoring

Pinal County Air Quality operates air quality mon itors that record ambi ent concentrations of several criteria pollutants. Criteria pollutants are those that the United States Environmental Protection Agency (EPA) has defined as a potential risk to health, and correspondingly defined a National Ambient Air Quality Standard (NAAQS). 1 

### The standards are intended to protect public health and welfare by setting limits on the allowa ble level of each pollutant in the ambient air.

The criteria pollutants are particulate ma tter less than or equal to 10 microns (PM 10 

### ), particulate matter less than or equal to 2.5 microns (PM 2.5 

### ), ozone (O 3 

### ), carbon monoxide (CO), sulfur dioxide (SO 2 

### ), nitrogen dioxide (NO 2 

### ), and lead (Pb).

Areas in which monitored air quality shows that the NAAQS are viol ated are defined as nonattainment for the offending pollutant. A nonatta inment designation requi res an area-specific curative implementation plan, typically includi ng stricter air quality permitting regulations on industrial facilities, mobile source emission cont rols and additional regulations on development. Generally, areas with monitored air quality that meet the standards are defined as attainment. Areas without sufficient monitoring data may also be defined as unclassifiable. Although the bulk of Pinal County is classified as attainme nt for all pollutants, Figure 1.1 illustrates the current pollutant-specific nonattai nment areas in Pinal County.

This document is arranged with several sections . Each section will address specific requirements of 40 CFR Part 58 or provide summary air quality data. The sections are organized accordingly:

Sections 1 describes 40 CFR Part 58 defined monitoring objectives and scales of representation. Section 2 provides Pinal County’s network desi gn, and measure of compliance with minimum site requirements, and an overview of how the Pinal County netw ork achieves precision

1 See Clean Air Act (“CAA”) §§ 108,109, and 40 CFR §50.1 et seq.

### 10 measurements as required by the monitoring rules. Section 3 describes each site in the network and evaluates the sites for compliance with si ting requirements set forth by EPA. Section 4 describes the proposed changes to the monitoring network. Section 5 describes the NAAQS standard for each pollutant monitored by Pina l County Air Quality and compares the data collected to the standard.

The appendices of this document presents a list of all the abbreviations used in the document (Appendix A), a picture and summary table for each monitoring site operated by Pinal County Air Quality (Appendix B), and a tabular summ ary of the monitori ng data (Appendix C).Figure 1.1

### 13 

# 1.0 National Ambient Air Quality Standards (NAAQS)

This section provides a brief description of the National Ambient Air Quality Standards (NAAQS) for ozone and particul ate matter, the pollutants of primary concern in Pinal County.

As background, the Clean Air Act requires EP A to set National Ambient Air Quality Standards (NAAQS) for six cr iteria pollutants; particle pollution (also known as particulate matter) is one of these. The Clean Air Act established two types of national air quality standards for particle pollution. Primary standards set limits to protect public health, including the health of "sensitive" populations such as as thmatics, children, and the elderly. Secondary standards set limits to protect public welfar e, including protection against visibility impairment, damage to animals, crops, vegetation, and buildings.

Ozone

The one-hour standard was established in 1971 and set at a level of 0.08 parts per million (ppm). In 1979, the standard was revised to 0.12ppm and was an exceedance based standard, which required that the number of expected exceedance be less than or equal to 1.0. An exceedance of the one-hour ozone standard occurred if an observed one-hour average was greater than 0.120 ppm. Generall y, the number of daily exceedances (only the daily maximum counts as an exceedance) equals the expected exceedance rate. Thus, the standard effectively allows only one ex ceedance to be recorded per calendar year.

EPA updated the ozone standard in 1997 and created an 8-hour standard. The 8-hour primary ozone standard was 0.08 ppm. The decision to revise the standards was challenged in court by a number of partie s and ultimately reached the U.S. Supreme Court. In 2001, the Court unanimously upheld the constitutionality of the 1970 Clean Air Act provision that authorizes EPA to set NAAQS to protect public health and welfare. EPA proceeded with implementing the 8-hour standard by making nonattainment designations in April 2004 and revoking the 1-hour standard in August 2005.

The latest revision to the ozone NAA QS was made on March 12, 2008. The 8-hour standard was set to a level of 0.075 ppm. In a ddition to changing the level of the standard, EPA specified the level of the standard to th e third decimal. An area will meet the revised standard if the three-year average of th e annual fourth-highest daily maximum 8-hour average at every ozone monitor is less than or equal to 0.075 ppm.

The Clean Air Act requires EPA to designate ar eas as attainment (meeting the standards), nonattainment (not meeting the standards), or unc lassifiable (insufficient data to classify) after the Agency sets a new standard , or revises an existing standard.

1. The following schedule will apply to the re vised ozone standards: States must make recommendations to EPA no late r than March 2009 for areas to be designated attainment, nonattain ment and unclassifiable, 2. EPA will issue final designations of atta inment, nonattainment and unclassifiable areas no later than March 2010 unless there is insufficient information to make these designation decisions. In that case, EPA will issue designations no later than March 2011.

### 14 3. States must submit State Implementation Plans outlining how they will reduce pollution to meet the standards by a date th at EPA will establish in a separate rule. That date will be no later than three y ears after EPA’s final designations. If EPA issues designations in 2010, then thes e plans would be due no later than 2013. 4. States are required to meet the standard s by deadlines that may vary based on the severity of the problem in the area.

EPA will issue a separate rule to address monitoring requirements necessary to implement the new standards. EPA intends to propose a monitoring rule in June 2008 and issue a final rule by March 2009.

Table 1.1

Key Year Action Level Averaging Period Form

1979 1-hour standard revised 0.120ppm 1 hour Expected exceedance 1997 8-hour standard proposed 0.08ppm 8 hour 3year average of the 4 th highest value 2005 1-hour standard revoked (Applies only in limited areas) 2008 8-hour standard revised 0.075ppm 8 hour 3year average of the 4 th highest value



### Table 1.2

Ozone Primary Standards Secondary Standards Level Averaging Time Level Averaging Time 0.075 ppm (2008 std) 8-hour 1 Same as Primary 0.08 ppm (1997 std) 8-hour 2 Same as Primary

0.12 ppm 1-hour 3 (Applies only in limited areas) Same as Primary

1 To attain this standard, the 3-year average of the f ourth-highest daily maximum 8-hour average ozone concentrations measured at each monitor within an area over each y ear must not exceed 0.075 ppm. (effective May 27, 2008)

2 (a) To attain this standard, the 3-year average of the fourth-highest daily maximum 8-hour average ozone concentrations measured at each monitor within an area over each y ear must not exceed 0.08 ppm. (b) The 1997 standard—and the implementation rules for that st andard—will remain in place for implementation purposes as EPA undertakes rulemaking to address the transition from the 1997 ozone standard to the 2008 ozone standard.

3 (a) The standard is attained when the expected num ber of days per calendar year with maximum hourly average concentrations above 0.12 ppm is < 1. (b) As of June 15, 2005 EPA revoked th e 1-hour ozone standard in all areas except the 8-hour ozone nonattainment Early Action Compact (EAC) areas.



### Particulate Matter (PM 10 

### and PM 2.5 

### )

The nation's air quality standards for particul ate matter were first established in 1971 and were not significantly revised until 1987, when EPA changed the indicator of the standards to regulate inhalable particles sm aller than, or equal to, 10 micrometers in diameter (that's about 1/4 the size of a single grain of table salt).

Ten years later, after a lengt hy review, EPA revised the PM standards, setting separate standards for fine particles (PM 2.5 

### ) based on their link to serious health problems ranging from increased symptoms, hospital admissions and emergency room visits for people with heart and lung disease, to premature death in people wi th heart or lung disease.

### 15 The 1997 standards also retained sl ightly revised standards for PM 10 

### which were intended to regulate "inhalable coarse particles" that ranged fr om 2.5 to 10 micrometers in diameter. PM 10 

### measurements, however, contain both fine and coarse particles.

EPA revised the air quality standards for particle pollution in 2006. The 2006 standards tighten the 24-hour fine part icle standard from the current level of 65 micrograms per cubic meter (μg/m 3 

### ) to 35 μg/m 3 

### , and retain the current annual fine particle standard at 15 μg/m 3 

### . The Agency decided to retain the existing 24-hour PM 10 

### standard of 150 μg/m 3



### . The Agency revoked the annual PM 10 

### standard, because available evidence does not suggest a link between long-term exposure to PM 10 

### and health problems.

The Clean Air Act requires EPA to review the latest scientific information and standards every five years. Before new standards are established, policy decisi ons undergo rigorous review by the scientific community, industr y, public interest groups, the general public and the Clean Air Scientific Advisory Committee (CASAC).

Table 1.3

National Ambient Air Quality Standards for Particle Pollution

Pollutant Primary Standard Aver aging Times Secondary Standard

Particulate Matter (PM 10 ) Revoked (1) Annual (1) (Arith. Mean)

150 μg/m 3 24-hour (2) Same as Primary
Particulate Matter (PM 2.5 ) 15.0 μg/m 3 Annual (3) (Arith. Mean) Same as Primary

35 μg/m 3 24-hour (4) Same as Primary

Footnotes: (1) - Due to a lack of evidence linking health problems to long-term exposure to coarse particle pollution, the agency revoked the annual PM 10 standard in 2006 (effective December 17, 2006).

(2) - Not to be exceeded more than once per year on average over 3 years.

(3) - To attain this standard, the 3-year average of the weighted annual mean PM 2.5 concentrations from single or multiple community-oriented monitors must not exceed 15.0 μg/m 3

. (4) - To attain this standard, the 3-year average of the 98th percentile of 24-hour con centrations at each populationoriented monitor within an area must not exceed 35 μg/m 3 (effective De cember 17, 2006).



### Lead

On October 15, 2008, EPA substantially streng thened the national ambient air quality standard for lead. The revised standards are 10 times tighter than the previous standards, set in 1978. EPA revised the level of the primary (health-based) standard from 1.5 micrograms per cubic meter ( μ g/m3), to 0.15 μ g/m3, measured as total suspended particles (TSP). The secondary (w elfare-based) standard is iden tical in all re spects to the primary standard.

The averaging time and form of the lead st andard were also revised. The calculation method for the averaging time was changed to use to a ‘rolling’ three month period with a maximum (not-to-be-exceeded) form, evaluated over a three-year period. This replaces the current approach of usi ng calendar quarters. A rolling three month average considers

### 16 each of the 12 three-month periods associated w ith a given year, not ju st the four calendar quarters within that year.

EPA estimates that 236 new or relocated mon itoring sites will be necessary to satisfy these monitoring requirements. Approximately ha lf of all newly required monitors are to be operational by January 1, 2010, with the othe r half of the mon itors operational by January 1, 2011. In addition, some existing lead monitors will be left in place and will continue to be used as part of the lead monitoring network.

National Ambient Air Quality Standards for Lead

Pollutant Primary Standard Averaging Times Secondary Standard Lead (as measured by TSP) 1.5 μg/m 3 (old standard) Avg. of Calendar Quarter Same as Primary

Lead (as measured by TSP) 0.15 μg/m 3 Rolling 3-Month Avg. 1 Same as Primary

Footnotes: (1) – Form of the standard requires evaluation of data collected over a 3 year period

### 17 

# 2.0 Monitoring Objectiv es and Spatial Scales

The design of an Ambient Air Quality M onitoring Network should meet six basic monitoring objectives listed in Appendix D of 40 CFR Part 58. These six objectives are:

1. Determine the highest concentrations exp ected to occur in the areas covered by the network. 2. Determine representative concentrati ons in areas of high population density. 3. Determine the impact on ambient pollution le vels of significant sources or source categories. 4. Determine general background concentration levels. 5. Determine the extent of regional pollu tant transport among populated areas. 6. Determine the welfare related impacts in more rural and remo te areas in support of secondary standards.

A State and Local Air Monitoring Station (SLAMS) network consists of monitoring stations that provide data to meet these monitoring objectives. Monitoring stations generally correspond to a spatia l scale identified in 40 CFR Part 58 Appendix D. Spatial scale of representativeness is described in terms of the physical dimension of the air parcel nearest to a monitoring station thr oughout which actual pollutant concentrations are reasonably similar. Table 2.1 lists these spatial scales. Table 2.1: Spatial Scales

Spatial Scale Dimension Microscale Several meters up to 100 meters Middle scale 100 meters up to 0.5 kilometers Neighborhood Scale 0.5 kilometers to 4.0 kilometers Urban Scale 4 kilometers to 50 kilometers Regional Scale Tens to hundreds of kilometers



### 40 CFR Part 58 Appendix D also describes the relationship between the monitoring objectives and the spatial scales that are generally most a ppropriate for each objective. Table 2.2 summarizes this relationship. Table 2.2: Monitoring Objectives

Monitoring Objective Appropriate Siting Scales Highest Concentration Micro, Middle, Neighborhood (Sometimes urban) Population Neighborhood, Urban Source Impact Micro, Middle, Neighborhood General / Background Neighborhood, Urban, Regional Regional Transport Urban / Regional Welfare-related impact Urban / Regional



### A Special Purpose Monitor (SPM) is a monitor th at is included in an agency’s monitoring network, but not part of the SLAMS netw ork. SPMs are generally used to monitor specific sources, although any of the above siting scales may be appropriate. In December 2006 the EPA revised 40 CFR 58.20 i ndicating that where a SPM operates for more than 24 months all data collected may be eligible for comparison to the relevant NAAQS.

### 18 40 CFR Part 50 and 53 define Federal Refere nce Methods (FRM) and Federal Equivalent Methods (FEM), which provide prec ise methodology for quantifying ambient concentrations of air pollutants. FRMs are monitoring methods that are associated with the NAAQS for the pollutant described in th e appendices to 40 CF R 50 and determined by EPA to be FRMs. FEMs are alternativ e monitoring methods that have been designated by EPA as obtaining "equivalent" results when compared to the FRM, as determined by 40 CFR 53. An additional opti on for air monitoring agencies is the Approved Regional Method (ARM). This designation requires the applying agency to conduct specific field testing and evaluation demonstrating that the method meets Class III precision and accuracy requirements li sted in Subpart C of 40 CFR Part 53.

Pinal County Air Quality uses FRMs to collect filter based PM 10 

### and PM 2.5 

### samples and Automated Equivalent Methods (FEMs) for continuous PM 10 

### and ozone.

Three types of PM 10 

### monitors are used throughout the monitoring network: 1) the filterbased high-volume sampler, 2) filter based medium volume sampler, and 3) the Tapered Element Oscillating Microbalan ce (TEOM) which measures PM 10 

### on a continuous basis.

Two types of PM 2.5 

### monitors are used throughout the m onitoring network: 1) the filter based medium volume sampler equipped with the appropriate size fr actioning device, and 2) the FDMS TEOM (Filter Dynamic Measurement System) which measure PM 2.5 

### on a continuous basis. Pinal County Air Quality has not pursued Approved Regional Method (ARM) designation for this instrument.

The Arizona Department of Environmental Quality (ADEQ) operated a sulfur dioxide (SO 2 

### ) analyzer in San Manuel, Pinal County until December of 2007. The San Manuel site was discontinued as proposed in th e SIP and Network Plan and subsequent attainment finding by EPA for the area. ADEQ retains authority to monitor copper smelters in Arizona.

ADEQ operates ozone and trac e level nitrogen oxide (NO x 

### ) analyzers at Queen Valley as a part of its PAMS network. There are curr ently no monitors in Pinal County that measure lead (Pb) although ADEQ operates samp lers in other portions of the state that measure lead. Refer to the State of Arizona Monitoring Network Plan for information on these criteria pollutants.

A process for relocating violating PM 2.5 

### monitors is described at 40 CFR Part 58.10 (c). The rule requires that the annual monitoring network plan must document how States and local agencies provide for the review of changes to a PM 2.5 

### monitoring network that impact the location of a violating PM 2.5 

### monitor or the creation/change to a community monitoring zone, including a de scription of the proposed us e of spatial averaging for purposes of making comparisons to the annual PM 2.5 

### NAAQS as set forth in appendix N to 40 CFR Part 50. The affected State or lo cal agency must document the process for obtaining public comment and include any comments received through the public notification process within their submitted plan.

Pinal County Air Quality does not intend to establish community monitoring zones as described in the rule or utilize spatial averaging for comparison to the PM 2.5 

### NAAQS. For the time period covered by this plan, Pinal County Air Quality does not intend to relocate

### 19 any violating PM 2.5 

### monitors. In the even t that a violating PM 2.5 

### monitor is relocated the following process will be utilized to a ddress the required public comment process:

1. Evaluation of the potential replacement site will include review and comparison of available pollutant data, mete orology, climatology, terrain, and siting characteristics. This information will be documented in a brief report. 2. Make notice of such a change in the annual monitoring plan. 3. If the change must be accomplished prio r to annual monitoring plan submittal, Pinal County will make appropriate notice via the agency Web page and invite participation from the public prior to relocation of the affected site. 4. Relocation of affected monitor.

### 20

### 21 

# 3.0 Network Design and Measurement Quality

3.1 Network Design

This section provides a list of m onitoring site designa tions. Table 3.1 and Table 3.2 identify Pinal County Air Quality’s current SLAMS and SPM designations, respectively.

The State Implementation Plan (SIP) as it applies to Pinal County does not make any SLAMS designations. In 2000 Pinal County co mpiled its first annual network review which included SLAM/SPM site designations . The past annual network reviews have been submitted to both ADEQ and EPA for comment.

Table 3.1: SLAMS Summary

Site Name AQS ID Classification Scale Objective Pollutant Apache Junction Fire Station 040213002 SLAMS Neighborhood Population PM 2.5 Apache Junction Fire Station 040213002 SLAMS Neighborhood Population PM 10 Apache Junction Maint.Yard 040213001 SLAMS Neighborhood Population O 3 Casa Grande Airport 040213003 SLAMS Neighborhood Population O 3 Casa Grande Downtown 040210001 SLAMS Neighborhood Population PM 2.5 Casa Grande Downtown 040210001 SLAMS Neighborhood Population PM 10 Coolidge Maintenance Yard 040213004 SLAMS Neighborhood Population PM 10 Eloy City Complex 040213014 SLAMS Neighborhood Population PM 10 Mammoth County Complex 040213006 SL AMS Neighborhood Population/ Background PM 10

Pinal Air Park 040213007 SLAM S Regional Background PM 10 Pinal County Housing Complex (HiVol) 040213011 SLAMS Neighborhood Population PM 10

Riverside Maintenance Yard 040213012 SLAMS Neighborhood SourceImpact PM 10 Stanfield County Complex 040213008 SL AMS Neighborhood Population PM 10



### Table 3.2: SPM Summary

Site Name AQS ID Classification Scale Objective Pollutant

Casa Grande Downtown TEOM 040210001 SPM Neighborhood Population PM 10
Combs School 040213009 SPM Neighborhood Population O 3 Combs School TEOM 040213009 SPM Neighborhood Population PM 10 Cowtown Road TEOM 040213013 SPM Microscale SourceImpact PM 10 Cowtown Road 040213013 SPM Microscale SourceImpact PM 10 Cowtown Road 040213013 SPM Microscale SourceImpact PM 2.5 County Complex Maricopa 040213010 SPM Neighborhood Population O 3 County Complex Maricopa TEOM 040213010 SPM Neighborhood Population PM 10

Pinal Air Park 040213007 SPM Regional Transport O 3 Pinal County Housing

Complex TEOM 040213011 SPM Neighborhood Population PM 10

Stanfield TEOM 040213008 SPM Neighborhood Population PM 10



### Pinal County Air Quality proposes to retain th e SPM designation for the monitors listed in Table 3.2. The ozone an alyzers at Combs School, County Comp lex Maricopa, and Pinal Air Park will operate from April 1 th rough October 31, the seasonal schedule. The PM 10 

### TEOM analyzers at Maricopa, Stanfield, Combs School, Casa Grande Downtown, and Pinal County Housing will also retain SPM designation. The Cowtown medium

### 22 volume FRM (47mm) and TEOM samplers are ope rated to monitor specific sources near the site.

3.2 AQS Requirements

In 2002 Pinal County Air Quality beg an enteri ng local monitoring data into the EPA’s AQS database. 40 CFR 58.16 requires that all am bient air quality data and associated quality assurance checks for all criteria pollutants be submitted to EPA via AQS. Additionally, an annual data certification is required by 40 CFR 58.15. The certification must be sent to EPA Region IX by July 1 stating that the data has been submitted correctly. Pinal County Air Quality will subm it an annual data certification for 2008 by July 1, 2009. Precision data for 2008 were submitted to AQS as of March 2009.

3.3 Minimum Network Requirements

40 CFR Part 58 Appendix D defines m inimu m monitoring requirements based on the population of the Metropolitan Statistical Area (MSA) and the design value for each NAAQS. Pinal County is part of the P hoenix-Mesa-Scottsdale MSA, which has a population of 4,039,182 (US Census Bureau, A nnual Estimates of the Population of Metropolitan and Micr opolitan Statistical Areas: April 1, 2000 to July 1, 2006 CBSAEST2006-01). The design value is a calcula ted value based upon the highest recorded concentration at a site in th e attainment or nonattainment area. The process for computing the value for each criteria pollutant is descri bed in the appendices of 40 CFR Part 50. For the purpose of this document the design va lues listed are the highest calculated concentrations recorded in Pinal Coun ty. Tables 3.3 through 3.5 list the minimum monitor requirements for PM 2.5 

### , PM 10 

### , and Ozone, respectively.

Table 3.3 PM 2.5 

### Monitoring Requirements (SLAMS)

Population (MSA) Most recent 3 yr design value ≥ 85% NAAQS Most recent 3 yr design value <85% NAAQS >1M 3 2 500K-1M 2 1 50K-500K 1 0



### Table 3.4 PM 10 

### Monitoring Requirements (SLAMS)

Population

(MSA) High Concentration Exceeds NAAQS by 20% or more (>180μg/m 3 ) Medium Concentration Exceeds 80% of NAAQS (>120μg/m 3 ) Low Concentration Less than 80% NAAQS (<120 μg/m 3 ) >1M 6-10 4-8 2-4 500K-1M 4-8 2-4 1-2 250K-500K 3-4 1-2 0-1 100K-250K 1-2 0-1 0

### 23 Table 3.5 Ozone Monitoring Requirements (SLAMS) Population

(MSA) Most recent 3 yr design value ≥ 85% NAAQS Most recent 3 yr design value <85% NAAQS >10M 4 2 4-10M 3 1 350K-4M 2 1 50K-350K 1 0



### Tables 3.6, 3.7 and 3.8 depict Pinal County’ s minimum monitoring requirements for PM 10 

### , PM 2.5 

### and ozone. The tables below show the minimum monitoring requirements are being met.

These tables only include SLAMS monitors op erated in Pinal County, and do not include monitors operated in other areas of the MSA. 40 CFR 58.20 states that SPM monitors may not be used to show compliance w ith the minimum monitoring requirements.

Table 3.6 lists the minimum monitoring requi rements for ozone. The highest 8-hour ozone concentration site in Pinal County is the Apache Junction ozone site. The calculated ozone design value using the Ap ache Junction 3-year average of the 4 th 

### highest 8-hour average is 0.080 ppm. This value is ≥ 85% of the NAAQS, which requires a minimum of three ozone monitors in the MSA.

Table 3.6: Minimum Monitoring Requirements for Ozone (O 3 

### )

MSA Population (US Census 2006) 8-hour Design Value (2006-2008) Minimum Monitors Required # of Active SLAMS Monitors Monitors Needed

Phoenix-MesaScottsdale 4,039,182 0.080 3 3 0



### Table 3.7 lists the minimum m onitoring requirements for PM 10 

### . The highest PM 10 

### concentration recorded at a SLAMS site ov er the last years of operation (2006-2008) was at 374 μg/m 3 

### at Stanfield. The value exceeds th e NAAQS by 20% or more and is considered a high concentration area. The high concentration desi gnation requires six to ten monitors in the MSA.

Table 3.7: Minimum Monitoring Requirements for PM 10

MSA Population (US Census 2006) Design Value (2005-2007) Minimum Monitors Required # of SLAMS Active Monitors Monitors Needed

Phoenix-MesaScottsdale 4,039,182 374 6 to 10 9 0



### Table 3.8 illustrates the minimu m monitoring requirements for PM 2.5 

### . The highest PM 2.5 

### 3-year average recorded at a Pinal County SLAMS site was at Casa Grande Downtown. The calculated PM 2.5 

### design value for the Casa Grande 3-year average of the annual means is 9.5 μg/m 3 

### and the 3-year average of the 98 th 

### percentiles is 19.9 μg/m 3 

### . Both values are < 85% of the NAAQS, which requires two monitors in the MSA.

### 24 Table 3.8: Minimum Monitoring Requirements for PM 2.5

MSA Population (US Census 2006) Design Value (2005-2007) Minimum Monitors Required # of Active SLAMS Monitors Monitors Needed

Phoenix-MesaScottsdale 4,039,182 9.5 (annual) 19.9 (24-hour) 2 2 0



### 3.4 Minimum Sample Frequency

PM 2.5 

### - The monitoring rule at 40CFR 58.12 (d )(1) states that required manual PM 2.5 

### samplers at SLAMS stations must operate on at least a 1-in-3 day schedule at sites without a collocated co ntinuously operating PM 2.5 

### monitor. For SLAMS PM 2.5 

### sites with both manual and continuous PM 2.5 

### monitors operating, the monitoring agency may request approval from the EPA Regional Admi nistrator for a reduction to 1-in-6 day PM 2.5 

### sampling at SLAMS stations or for seasonal sampling. The EPA Regional Administrator may grant sampling frequency re ductions after consideration of factors including, but not limited to, the historical PM 2.5 

### data quality assessments, the location of current PM 2.5 

### design value sites, and their regulatory data needs. Sites that have design values that are within plus or minus 10 percent of the NAAQS (±10% of 35μg/m 3 

### is 31.5- 38.5) and sites where the 24-hour values ex ceed the NAAQS for a period of 3 years are required to maintain at least a 1-in-3 day sa mpling frequency. Sites that have a design value within plus or minus 5 percent of the daily PM 2.5 

### NAAQS (±5% of 35μg/m 3 

### is 33.25-36.75) must have an FRM or FEM operating on a daily schedule.

In 2008 Pinal County proposed and received ap proval from EPA Region IX to reduce the sample frequency at the Casa Grande site from 1 in 3 to 1 in 6 after the end of the 2008 sample year. This change was implemented on January 1, 2009. During 2007 samples were collected on the 1 in 3 schedule. Prior to 2007 the site operated at a 1 in 6 frequency for 8 years. During the time this site has operated the 3 year average of the 98 th 

### percentile value has not exceeded 21μg/m 3 

### . With this change in sample frequency equipment was made available to begi n collecting a precision PM 2.5 

### measurements at the site. Sample frequencies are summarized in Table 3.9.

The sample frequency at Apache Junction will not change.

Table 3.9 PM 2.5 

### Sampling Frequencies

Site Name 3-Year Average of 98 th percentile 2006-2008 Current Sample Frequency Required Frequency Casa Grande 19.9 1 in 6 1 1 in 3 Apache Junction 13.1 1 in 3 1 in 3
1. See description in this regarding precision samples and sample frequency



### PM 10 

### - The monitoring rule at 40 CF R 58.12 (e) states that for PM 10 

### sites, the minimum monitoring schedule for the site in the area of expected maximum concentration shall be based on the relative level of that monitoring site concentration with respect to the 24- hour standard. Pinal County currently opera tes a continuous monitor at its maximum PM 10 

### concentration site. Therefore, no change to the PM 10 

### sample frequency is required.

### 25 3.5 Measurement Quality Checks

To provide a quality assurance dem onstrati on, Appendix A of 40 CFR Part 58 requires a minimum number of collocated sampling sites based on the total number of manual (filter-based) particulate monitoring sites in the network. Generally, precision sampling involves operating two identical collocated samplers at th e same location on the same sampling schedule.

Appendix A of 40 CFR Part 58 Section 3.3.1 requires fifteen percent of the filter based PM 10 

### monitoring sites, by collec tion method, in a network to be collocated. Pinal County Air Quality currently operates a total of ten PM 10 

### sites. Seven sites utilize high-volume samplers and 2 sites utilize medium-volume samplers (47mm). Table 3.10 summarizes the status of collocated sites in the PM 10 

### network.

The Pinal County Housing site is u tilized to collect the required PM 10 

### collocated HighVolume samples. Pinal County Air Quality doe s not currently operate a precision site for comparing medium –volume filter based PM 10 

### monitors (47mm) and, therefore, does not meet the required minimum number of collocated sites. The addition of 1 collocated site is required. This topic is addressed in Section 5.0, Pr oposed Changes to the Network.

Table 3.10: Minimum Collocated Monitoring Requirements for PM 10

Sampling Method Total Number of Sites Required Collocated Sites Number of Collocated Sites

High-Volume (Wedding or Anderson) 8 1 1 (Pinal County Housing) Medium-Volume (Partisol or RAAS) 2 1 0



### Appendix A of 40 CFR Part 58 does not require collocation of continuous PM 10 

### monitors. Measurement quality of conti nuous TEOM instrument is achieved through flow verification checks conducte d at least once per month.

Appendix A of 40 CFR Part 58 Section 3.2.5 requires PM 2.5 

### networks to include collocated sampling at fifteen percent of the mo nitoring sites in a network. Pinal County Air Quality operates three PM 2.5 

### sites with one collocated measurement made at Casa Grande Downtown. As described above, this was a change made in 2009 to correct a deficiency note in the 2007 plan.

3.6 Ozone Season Definition

In the 2007-2008 Annual Am bient Monitoring Netw ork Plan Pinal County requested and was granted a modification to the area ozone season in accordance with 40 CFR Part 58, Appendix D, Paragraph 4.1(i). The modificatio n to the ozone season defined the season as April 1 through October 31.

Pinal County continues to believe the appr opriate ozone season for sites under our operation to be April 1 through October 31 each year. This is based upon the updated data summary below from the Casa Grande and Apache Junction ozone sites for years 2002 through 2008, which with the excepti on of 2 days; March 15, 2007 at Apache Junction, March 31, 2008 at Apache Junction and Casa Grande, demonstrates that ozone

### 26 concentrations have not historically ex ceeded 75 ppb during the period from October through March. See Figure 3.1 below. Additionally, a 1998 EPA guidance document entitled, “Guideline for Selecting and Modi fying the Ozone Monitoring Season Based on an 8-Hour Ozone Standard” supports a shor ter ozone season for Arizona based upon data collected from 1990 through 1995.

The modified seasonal schedule is applied to the following sites: Combs School, Pinal Air Park, and Maricopa County Complex. The Casa Grande Airport and Apache Junction Maintenance Yard would continue to operate on a January to December schedule. With the past approval of this modification, Pinal County made appropria te corrections to the seasonal definition in the AQS databa se and annual monitoring plan.

Number of Days With Ozone Concentration 75ppb or Greater 2002-2008 8-Hour Average

0 5 10 15 20 25

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DECDays

Casa Grande Apache Junction



### Figure 3.1

### 27 3.7 Quality System Requirements

Pinal County Air Quality subm itted a Quality Assurance Project Plan (QAPP) to EPA Region IX in January 2007. The QAPP covere d all aspects of the ambient monitoring network operations, filter weighing process, a nd data quality review. All instrument SOPs were completed and included in the QAPP. EPA provided feedback on the QAPP in July of 2008. Pinal County Air quality is currently revising appropriate sections of the QAPP to address the comments.

All flow rate standards used by Pinal Count y are traceable to NI ST Standards and are recertified annually. Th e ozone standard is verified by the California Resource Board on an annual basis and the ozone transfer sta ndard is verified by Pinal Staff monthly.

Through ADEQ, Pinal County is a participan t in the EPA National Performance audit program (NPAP) and the PM Performance Evaluation Program (PEP). Pinal County sites are included in the EPA sponsored audit programs.

ADEQ conducts performance audits of Pina l County monitors according to frequencies described in 40 CFR Part 58. All flow rate standards used by ADEQ are traceable to NIST Standards and a recertified annuall y. The ozone standard used by ADEQ is checked twice per year.

Currently, EPA does not consider Pinal Count y Air Quality a primary quality assurance organization as defined by 40 CFR Part 58 Appendix A, paragraph 3.1.1. During 2009 Pinal County will work with EPA Re gion IX gain this designation.

3.8 Lead Monitoring Network Description

The strengthening of the L ead NAAQS resulted in a revision to 40CFR Part 58.10. The revision requires state and local agencies to describe required lead monitoring networks in the annual monitoring network plan a nd submit the description to the Regional Administrator by July 1, 2009.

Appendix D to Part 58 entitled, “Network Design Criteria for Ambient Air Quality Monitoring”, requires states and local agenci es to establish ambient lead monitoring under two specific conditions: 1) Source-oriented SLAMS level monito ring located to measure the maximum lead concentration in ambient air resu lting from each lead source which emits 1.0 or more tons per year based on eith er the most recent National Emission Inventory (NEI) ( http://www.epa.gov/ttn/chie f/ eiinformation.html ) or other scientifically justifiable methods and data (such as improved emissions factors or site-specific data), and 2) Lead monitoring in each CBSA with a population equal to or greater than 500,000 people as determined by the late st available census figures. At a minimum, there must be one non-source-or iented SLAMS site located to measure neighborhood scale lead concentrations in urban areas impacted by re-entrained dust from roadways, closed industrial sources which previously were significant

### 28 sources of lead, hazardous waste sites, construction and demolition projects, or other fugitive dust sources of lead.

To assess a potential point-source triggered requirement for ambient lead monitoring in Pinal County the 2005 NEI and internal emissi on inventory reports were reviewed by Pinal County Air Quality Staff. Table 3.11 summarizes lead emission calculated by NEI or reported through the Toxics Release Invent ory (TRI) in 2005. As reported to NIE in 2005 only one source in Pinal County exceeded the 1 ton per year threshold. A review of the ASARCO LLC Ray Operations Mine 2007 emission inventory report, which is required through air quality operating permit, shows a revision to the annual lead emission rate from 1.27tpy to 0.014tpy. The revision was described in a May 12, 2008 letter accompanying the annual emission inventory submittal. Air Quality permit management reviewed and accepted the revised emission rate.

The second pathway for required ambient l ead monitoring arises through CMSA/MSA population. Pinal County is included in the Phoenix-Mesa-Scottsdale, AZ MSA with a 2006 population of approximately 4.1 million pe ople. This is above the 500,000 person population threshold described above. Although Pinal County is included in the MSA the majority of the population re sides in Maricopa County.

After review of the inventory and MSA population, Pinal County Air Quality has concluded that monitoring for ambient lead in the county will not be conducted. This conclusion is based upon the following; 1) no point source in the c ounty emits lead above the 1 ton per year threshold or the possible revised threshol d of 0.5 ton per year and, 2) Pinal County assumes that the MSA required monitoring will be conducted in Maricopa County. Pinal County Air Quality will revisit th e need and feasibility of lead monitoring as source emissions and ec onomic conditions change.

Table 3.11: NEI 2005 Point Source Lead Emissions in Pinal County Facility Name 2005 NEI v 2 Emissions (tpy) TRI2005 TRI Emissions (tpy) FABRICATED PRODUCTS INC. DBA S EAFAB METALS CO. 0.00555 0.00555

ASARCO LLC RAY OPERATIONS MINE 0.00025 1.27275

OWENS CORNING ELOY PLANT 0.0411 0.0542 WESTILE INC. 0.00005 0.00005

### 29 

# 4.0 Monitoring Site Descriptions

This section describes the purpose and classi fication of each monitoring site operated by Pinal County Air Quality. Appendix B contains images and summary tables for each site. The changes that have occurred or are planne d at each site are detailed within each subsection. Each site has been evaluated for compliance with the si ting criteria listed in 40 CFR Part 58 Appendix D (Network Design) and Appendix E (Probe and Path Siting).

4.1 Apache Junction Fire Station

This site is located beh ind Apache Junc tion Fire Station #2 on Bureau of Land Management (BLM) property. Apache Juncti on lies at the fringe of the Phoenix metropolitan area, where urban development meets the Tonto National Forest and Superstition Wilderness. The site sits on th e eastern boundary of the City of Apache Junction with residential homes to the east. Undisturbed desert im mediately surrounds the site to the north, south and west with re sidential homes beyond that. The Superstition Mountain Range is located approximately one mile east of the site. The purpose of the site is to quantify PM 2.5 

### and PM 10 

### concentrations affecting the surrounding population on a neighborhood scale. This site is included in the statewide PM 2.5 

### network.

The site consists of a High-Volume PM 10 

### sampler and a FRM sequential PM 2.5 

### sampler. The PM 10 

### sampler operates on a one in six day schedule and the PM 2.5 

### sampler operates on a one in three day schedule.

The site historically consisted of two Andersen FRM PM 2.5 

### monitors, one of which operated every third day. The samplers did not take precision samples; instead their operation alternated. One sampler was operated on each run day so that the number of site visits was reduced. In June 2004 a sequential R&P FRM PM 2.5 

### sampler was installed in replace of the Andersen PM 2.5 

### monitors.

One High-Volume PM 10 

### sampler from the Apache Junction Maintenance Yard (described in section 3.2) was moved to this site on July 1, 2003. Samples were collected at both sites until January 1, 2004 to de velop a correlation between th e two sites. The correlation is discussed further in section 5.3.1. As of January 1, 2004 the Apache Junction Fire Station site is the only PM 10 

### site in Apache Junction.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.2 Apache Junction Maintenance Yard

This site is located within the Pinal County Public W orks Yard and is in the center of Apache Junction. Three major roads surround the site: State Highway 88, Idaho Road, and Superstition Boulevard. The maintenance ya rd area is graveled, well maintained, and historically activity in the yard has not adve rsely affected the samplers. The historical purpose of this site was to quantify PM 10 

### concentrations affecting the surrounding population on a neighborhood scale, quantify carbon monoxide concentrations near a major intersection on a middle scale, and qua ntify ozone concentrations on the eastern

### 30 boundary of the Phoenix metropolitan area. The oz one concentration at this site reflects both regional transport and nei ghborhood scale population exposure.

Historically, the site consiste d of two Wedding High-Volume PM 10 

### monitors that collected precision samples on a one in six-da y schedule, an ozone monitor, a carbon monoxide monitor, a wind system, a barometr ic pressure sensor and a temperature and relative humidity sensor. The inlet funnel on the ozone monitor was changed from stainless steel to Pyrex glass in 2001. The site has met 40 CFR Part 58 Appendix D and E criteria since then.

In an effort to better utili ze the resources available to Pinal County Air Quality, the District removed the carbon monoxide m onitor located at this site on May 28 th 

### , 2002. The reasoning behind this is discussed in deta il in section 5.1 of this document.

One of the PM 10 

### High-Volume monitors located at this site was moved to the Apache Junction Fire Station site on July 1, 2003. PM 10 

### monitoring took place at both sites until January 1, 2004, so that a correlation betw een the two sites could be developed. On January 1, 2004 the remaining PM 10 

### High Volume monitor was moved to the Pinal County Housing site in order to create a co-located PM 10 

### site. Refer to section 4.12 of this document for details on the Pi nal County Housing site.

The existing tower at the Apache Junction Maintenance Yard site, on which the wind system is mounted, historically was not stab le enough to produce accurate wind direction. The mounting of the meteorological equipmen t was reconfigured in May 2007 so that accurate measurements could be taken.

4.3 Casa Grande Airport

This site is located within the Casa Grande Municipal Airport. Casa Grande lies about twenty m iles south of the Phoenix urban area, in a broad desert pl ain largely dominated by open field agriculture. A small industrial park is located within the airport complex and there are residential subdivisions to the north, south, and east of the airport. The airport is on the north edge of Casa Gra nde, although the entire surrounding area is growing rapidly. To the east of the airport approximately a quarter of a mile is a major thoroughfare, Pinal Avenue.

The objective of this site is to quantify ozone concentrations south of the Phoenix metropolitan area. The ozone concentration at this site reflects both regional transport and neighborhood scale population exposure.

In the past carbon monoxide was also monitored at this site. In an effort to better utilize the resources available to Pinal County Ai r Quality, the District removed the carbon monoxide monitor located at this site on October 11, 2002.

The site currently consists of an ozone an alyzer, a wind system, a barometric pressure sensor and a temperature and relative humidity sensor. In August 2006 a new site shelter was installed. The site meets 40 CFR Part 58 Appendix D and E criteria.

### 31 4.4 Casa Grande Downtown

This site is located on the roof of an Ariz ona Departm ent of Economic Security building in the downtown area of Casa Grande. A core business district surrounds the site followed by residential areas in all directions . The purpose of the site is to quantify PM 2.5 

### and PM 10 

### concentrations affecti ng the surrounding population on a neighborhood scale.

Historically, the site consisted of a High-Volume PM 10 

### sampler and a PM 2.5 

### FRM sampler. The samplers were moved further away from a nearby furnace flue in September of 2001. The High-Volume PM 10 

### sampler operates on a one in six-day schedule. The PM 2.5 

### monitor at this site was upgraded from an Andersen PM 2.5 

### FRM sampler to a single channel R&P PM 2.5 

### FRM sampler in March 2004. The PM 2.5 

### FRM sampler had operated on a one in six day sche dule since 1999. On January 1, 2007 the sample frequency was changed to one in three days to meet new monitoring requirements. In March of 2007 a second PM 2.5 

### FRM sampler was installed so that operation could alternate between the two a nd reduce trips to the site. A continuous PM 10 

### TEOM was installed in March of 2007.

For the first sample of 2009, the sample frequency of the two PM 2.5 

### samplers was change from a frequency of 1 in 3 to 1 in 6 to allow for precision measurement. This change was proposed in the 2007 network plan.

On December 31, 2008 the HiVolume sampler was moved from Casa Grande Downtown to Stanfield and replaced with a PM 10 

### Thermo Partisol.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.5 Combs School

This site is located within the J.O. Com b s Elementary School District campus and is approximately ten miles south of Apache J unction in an area that is rapidly being developed for residential use. The area has historically been dominated by open field agriculture, although residential developments ha ve been built or are being planned to the north, south, east and west of the site. Th is site is used to quantify ozone and PM 10 

### concentrations southeast of the Phoenix metropolitan area. The ozone concentration at this site reflects regional transport and neighborhood population exposure. The PM 10 

### concentration at this site reflect s neighborhood scale population exposure.

This site was installed in June of 2002 and ozone data recording be gan in July 2002, thus data for a portion of the 2002 ozone season are missing. In March of 2007 a continuous PM 10 

### TEOM was added at the site.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.6 Coolidge Maintenance Yard

This site is located within the Pinal Count y Public W orks Yard on the east side of Coolidge. Coolidge lies about thirty miles sout heast of the Phoenix ur ban area in a desert basin largely dominated by open field agricultu re. Residential homes surround the site to the north, south, and east. West of the site is a railroad track with a business district on

### 32 the other side. The purpose of this site is to quantify PM 10 

### concentrations affecting the surrounding population on a neighborhood scale.

The site consists of a High-Volume PM 10 

### sampler, which collects samples on a one in six-day schedule. Due to a scheduled demolition, the monitor was moved from the roof of a cargo trailer to a ground level stand in June of 2002. The monitor was moved approximately fifteen meters to the south and the inlet height was reduced from 5.6 meters to 3.4 meters.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.7 Cowtown Road

This site is located approxim ately four miles southeast of the City of Maricopa. The site also lies within an irrigated agricultural plain, with active and retired agricultural operations to the north, northwest and east. Feedlots, a grain processing complex, and a commercial composting facility operate to the south, southwest and southeast. This site is used to look at several PM 10 

### sources in the area, incl uding agriculture, the grainprocessing complex, the feedlo ts and county dirt roads.

The site was installed and data recording began in November of 2001. Since neither a quarterly nor annual average can be obtaine d from the two months of 2001 data this document will contain 2002 and subsequent data fr om this site. The site first consisted of a TEOM that collected continuous PM 10 

### data, a wind system, and a temperature and relative humidity sensor. The area immediatel y surrounding the site was fenced off (at least 100 feet in all directions ) in September of 2003 in orde r to stabilize the surrounding soil. The surrounding soil has subsequently be en stabilized relatively well with the exception of the area to the south of the sample rs. This area is a right of way that runs along the Casa Grande – Maricopa Highway and it was regularly disturbed by farm machinery (for instance a tractor and disc) in order to control weeds. In December of 2006 the right of way area adjacent to the site was fenced off to pr event this activity. Since December 2006 this site meets 40 CFR Part 58 Appendix D and E criteria.

A new shelter was installed at this si te in August 2003 to accommodate additional equipment. A time-lapse video system was installed at this time and was operated until July 2006. The TEOM at this site was upgraded to a new unit in June 2004. The new unit still sampled PM 10 

### and had the filter dynamics measur ement system (FDMS) installed as an option. This option is designed to better account for particles that are in a gaseous form. The FDMS unit had difficultly operating in the harsh environment at this site from the beginning. Due to the maintenance pr oblems with the FDMS unit, a TEOM unit without the FDMS option wa s set up as the primary monitor in January 2005.

The FDMS TEOM was operated periodically du ring 2005 in an effort to find ways to maintain the sampler in this harsh environment. During May and June of 2005 the FDMS TEOM was operated along with the collocate d regular TEOM unit, both collecting PM 10


### . During this time it was found that the regul ar TEOM unit was reading approximately 30% higher than the FDMS TEOM unit. District staff worked with representatives from the manufacturer of the units , R&P, to determine the cause of this discrepancy.

### 33 Two issues were identified w ith the regular TEOM unit. First, it was found that the fiveminute averages of this unit often recorded a large negative number directly after an extremely large positive number (1000 μ g/m 3 

### or more). The manufacturer of the unit concluded that the flow c ontrollers were over correcting for the extremely large particulate matter concentra tions and correspondingly crea ting the negative numbers. The second issue identified was that the unit ofte n recorded elevated noise vibrations when extremely large concentrations were record ed. This was a result of a large amount of particulate matter being deposited on the os cillating microbalance in a short amount of time. In order to correct both of these discrepancies the ma in inlet flow on the regular TEOM unit was reduced to 1 liter per minut e (from 3 liters per minute) in August 2005. The manufacturer has used th is alternate setting in othe r areas with extremely high particulate matter concentrations. The main fl ow setting of 1 liter pe r minute still retains the FEM status of the unit.

A filter based Andersen FRM PM 10 

### unit and a filter based Andersen FRM PM 2.5 

### unit were installed at this site in August of 2005. The units are both operated on a one in six day schedule. This allows PM 10 

### , PM 2.5 

### and surrogate coarse data to be collected. Coarse material refers to particulate matter that is between 2.5 microns and 10 microns in size. The surrogate coarse data is extrapolated by subtracting the PM 10 

### concentration from the PM 2.5 

### concentration.

Comparing the regular PM 10 

### TEOM data (with the main flow set at 1 liter per minute) to the FRM filter based PM 10 

### data yields an excellent correlation. The average percent difference between the two is 6.4% for the time period of August 2005 to June 2006. This demonstrates that setting the main flow to 1 liter per minute on a regular PM 10 

### TEOM is an appropriate operating method in this harsh environment.

Subsequent attempts during 2005 to build a suitable correlation be tween the regular PM 10 

### TEOM and the FDMS PM 10 

### TEOM unit were not successful. The FDMS PM 10 

### TEOM continued to read approximat ely 15% below the regular PM 10 

### TEOM. This does not appear to be a logical relationship since th e FDMS unit is designed to better account for particles that are in a gaseous form and thus should be slightly higher than the regular PM 10 

### TEOM. Further conversations with the manufacturer of the unit suggest the dryer that is built into the FDMS un it is scavenging coarse materi al. At this time Pinal County Air Quality has concluded that the FDMS TEOM unit is not suitable for measuring PM 10 

### in this harsh environment that has a large co arse fraction. (The manufacturer may have a second-generation drier availabl e in the future that woul d prevent the scavenging of coarse material in situations like this.)

Due to the difficulty and expense of operating the FDMS TEOM in this environment, the instrument was shut down in May of 2007.

The time-lapse video system was relocated to the Stanfield site in July of 2006. The Cowtown site was several hundred yards from the feedlots being observed and did not allow the camera to record an overall view of the dust events.

On January 15, 2009 the PM 10 

### and PM 2.5 

### Anderson samplers were replaced with Thermo PM 10 

### and PM 2.5 

### Partisol samplers.

### 34 4.8 Eloy County Complex

This site is located on the roof of the Pina l County Justice Court bui lding. Eloy also lies in the agricultural basin of the County. A s mall business dist rict to the north and south and residential homes to the east and west surro und the site. The purpose of this site is to quantify PM 10 

### concentrations affecting the surrounding population on a neighborhood scale.

This site replaced the Eloy City Complex s ite, which was approximately 300 yards to the south, in March 2007. The site consists of a High-Volume PM 10 

### sampler, which collects samples on a one in six-day schedule.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.9 Mammoth County Complex

This site is located on the roof of the Mammoth County Complex. Mammoth lies near the southeast corner of the C ounty, approximately thirty miles northeast of Tucson and eighty-five miles southeast of Phoenix. Resi dential homes surround the site on all sides. The purpose of this site is to quantify PM 10 

### concentrations affecting the surrounding population on a neighborhood scale. This site al so serves as a background site for the eastern portion of the county, which historically has been economically dominated by copper mining. The surrounding elevations rang e from 2000 to 5500 feet. Aside from the mining operations, the landscape is dominated by native vegetation.

The site consists of a High-Volume PM 10 

### sampler, which collects samples on a one in six-day schedule.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.10 Maricopa County Complex (City of Maricopa)

This site is located behind the County Com ple x in city of Maricopa. Maricopa lies about fifteen miles south of the Phoenix urban area. Historically the area was a small residential area surrounded by pecan orchards, cattle feed lots, and open-field agriculture. Recently, development has added a substantial number of houses near the monitoring site and additional subdivisions are planne d in every direction. This site is used to quantify ozone concentrations and PM 10 

### concentrations in the area. The ozone concentration at this site reflects both regional transport and nei ghborhood scale population exposure. The PM 10 

### concentration at this site reflect s neighborhood scale population exposure.

This site was installed in June of 2002 and an ozone sampling began in July 2002, thus data for a portion of the 2002 ozone season are missing. The ozone monitor is operated seasonally. In December 2004 a PM 10 

### TEOM unit was installed. Therefore, only data beginning January 2005 are included in the document.

The site meets 40 CFR Part 58 Appendix D and E criteria.

### 35 4.11 Pinal Air Park

This site is located at water well number two with in the Pinal Air Park complex. Pinal Air Park lies about twenty miles northwest of Tucson, at the Pina l/Pima County line. The site is immediately surrounde d by undisturbed desert on all si des with an industrial park and airport lying to the west. The purpose of this site is to quantify background PM 10 

### concentrations and transport ozone concentrations on a regional scale. This site serves as a background particulate matter site for th e central and western portion of the county, which is dominated by agriculture and lo w elevations (generally around 1500 feet).

The site includes a High-Volume PM 10 

### sampler, which collects samples on a one in sixday schedule and an ozone monitor that is operated seasonally. An ozone analyzer was installed in June of 2002 to assess regional transport from the Tucson metropolitan area. Data collection from this ozone monitor did not begin until July of 2002, thus the data set for 2002 only includes a portion of the ozone seas on. The ozone concentration at this site reflects both regional transport and ne ighborhood scale population exposure.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.12 Pinal County Housing Complex

This site is located within the Pinal C ounty Housing Com plex and is approximately eleven miles east of Casa Grande in the heart of the agricultural basin of the County. The site was installed in July of 2002 to repl ace the Eleven Mile Corner site, which was approximately 1 mile to the south. The Pina l County Housing site be tter represents the particulate matter impact on the surrounding po pulation since the site is adjacent to a subdivision. The site is located within a fen ced area that houses the sewer lift station for the subdivision. The enclosure is immediatel y surrounded by native de sert growth with active and retired agricultural areas beyond th at in all directions. The County Housing subdivision lies just to the sout heast of the enclosure. A sm all dairy, two cotton gins, and the Pinal County Fairgrounds are approximately one mile to the south of the Pinal County Housing Complex site. This site is used to evaluate several PM 10 

### sources in the area, including cotton gins, fairground activity, and agricultural activity.

The site originally consisted of a High-Volume PM 10 

### sampler running on a one in six day schedule, a continuous PM 10 

### TEOM, a wind system, and a relative humidity and temperature sensor. On January 1, 2004 a second High-Volume PM 10 

### sampler was installed to collect precision samples. Th is replaced the Apache Junction Maintenance Yard as the precision site in the network.

During 2005 it was discovered that one of the High-Volume PM 10 

### samplers, PCH West, was not operating properly; the second High- Volume sampler, PCH East, has operated within specifications throughout this time period. The malfunctioning Anderson HighVolume PM 10 

### sampler was removed from service in July 2006. This particular unit had a quick connect device to secure the inlet that none of the other Andersen High-Volume units operated by the District have. It appears this quick connect device has deteriorated over time and was causing the unit to operate outside of the required specifications. Since one of the Anderson High-Volume units wa s retired, two Wedding High-Volume units were installed at this site in July 2006 to collect precision samples.

### 36 In 2008 the site will be moved approximately 20 yards to the south. A new shelter and 10 meter wind tower will be added (see section 4.2 for additional detail).

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.13 Riverside Maintenance Yard

This site is located at the Pinal County Pub lic W orks Yard in Riverside. The site is approximately thirteen miles southeast of S uperior and four miles northwest of Kearny. The Ray Mine, an active open pit copper mine , is approximately two miles east of the monitoring site. The monitor is located in the Mineral Creek valley, down slope from the mine operations. The purpose of this site is to analyze off-site source impacts of the mine’s tailing impoundments (neighborhood scale).

This site was installed in March of 2003 and consists of an Andersen High-Volume PM 10 

### sampler collecting samples on a one in six- day schedule. In early 2006, Pinal County Public Works Department moved a mobile offi ce building onto the site. The addition of this building did not affect the siting of the sampler.

The site meets 40 CFR Part 58 Appendix D and E criteria.

4.14 Stanfield County Complex

This site is located behind the Stanfield County Com plex. Stanfield lies about fifteen miles west of Casa Grande, and about thir ty miles south of the Phoenix urban area. Residential homes surround th e site on all sides, but the surrounding landscape is dominated by open-field agriculture. Sizeable feedlot and dairy operations lie about three miles to the north, east and west. The pur pose of this site is to quantify PM 10 

### concentrations affecting the surrounding population on a neighborhood scale. Over the last several years this site may have been im pacted by increased activ ity at existing cattle feedlots and new dairies located ea st, west and north of the site.

Historically, the site consisted of a High-Volume PM 10 

### sampler, which collected samples on a one in six-day schedule. In February 2006 a PM 10 

### TEOM was installed at this site to collect continuous data. In April 2006 th e Wedding High-Volume sampler was replaced with a medium volume Anderson FRM sampler. The Anderson sampler was replaced with an FRM Partisol medium volume sampler in November 2007.

A time-lapse video system which was previously installed at the Cowtown site (described in section 3.9) was added to this site in July 2006. The new location will allow the camera to record an overall view of the dust events observed at the feedlots that are approximately three miles west of the site.

On December 31, 2008 the PM 10 

### Partisol sampler at Stanfi eld was replaced with the High-Volume sampler from Casa Grande Downtown. Pinal County Air Quality is proposing to discontinue filter based PM 10 

### sampling at this site and designate the PM 10 

### TEOM located here as a SLAMS (see section 5.3 for additional detail).

The site meets 40 CFR Part 58 Appendix D and E criteria.

### 37 4.15 Queen Valley

This site is located at the Queen Valley water tank. Queen Valley is approxim ately sixteen miles southeast of Apache Junction a nd just south of the Superstition Wilderness Class I area. The site is on the south edge of Queen Valley and is surrounded by rugged terrain and native vegetation. The equipment at the site is owned and operated by ADEQ. This is an ADEQ SLAMS site which is part of the Photochemical Assessment Monitoring Station (PAMS) network that provi des data regarding ozone transport from the Phoenix urban area. ADEQ operates instru ments at this site to measure ozone, reactive nitrogen oxides (NOy), and PAMS volatile organic compounds. ADEQ also operates a nephelometer, temperature and relati ve humidity sensors at the site. The ozone data from this site is included in Appe ndix B of this document because the site demonstrates ozone transport into Pinal C ounty. Please refer to the State of Arizona Monitoring Network Plan for additional information.

Pinal County Air Quality serves as the ope rator for the Intera gency Monitoring of Protected Visual Environments (IMPROVE) samp ler located at this site. This sampler provides particulate matter data and speciation data for assessing the impact of particulates on visibility at the nearby Superstition Wilderne ss Class I area. Please refer to the IMPROVE web site at http://improve.cnl.ucdavis.edu/ for the data from this monitor.

### 38

### 39 

# 5.0 Proposed Changes to the Network

This section describes any ne w sites that Pinal County Air Quality plans to install and summarizes recent changes to the network.

5.1 Stanfield

At the conclusion of the 2009 m onitoring year the Hi Volume filter-based PM 10 

### sampler will be discontinued at the Stanfield site. The filter-based measurement is currently categorized as SLAMS and collects samples on a 1 in 6 schedule. Upon the removal of the Hi Volume sampler the continuous PM 10 

### TEOM SPM will be designated the SLAMS. After reviewing concurrent data it was determined that both PM 10 

### measurements were no longer needed at the site. Da ily data will continue to be available at this site.

5.2 Casa Grande Downtown PM 2.5


### Section 3.5 Measurement Quality Check s described the shortage of a PM 2.5 

### precision measurement site in the network. This shor tage was corrected at the beginning of the 2009 sample year with the move from 1 in 3 sa mple frequency to 1 in 6 using the existing samplers. If in future years additional equipm ent is available, a return to the 1 in 3 schedule will be made.

5.3 Pinal County Housing Relocation

During 2008-2009 a portion of the Pinal County Housing site will be moved from its current location to a new area approximately 20 Yards to the south. The purpose of the relocation is to gain additional space to acco mmodate a monitoring shelter and equipment needed for the planned EPA/Pinal County 2008-2009 Rural Coarse Particulate Speciation Study. The move will not result in a substantial change in the site exposures or pollutant concentrations.

Additionally, a PSD level meteor ological site is begin ev aluated for the Pinal County Housing site. If funding is available the 10 meter tower and appropriate equipment will be added during 2009.

5.4 Medium Volume Precision Measurement

As discussed in Section 3.5, the PM 10 

### network currently lacks a precision measurement for medium volume samplers. This precision measurement first became necessary with the addition of a Thermo PM 10 

### Partisol 2000H to the networ k in November of 2007. If funding is available, Pinal County will proc ure the required equipment during the 2009- 2010 monitoring year and begin measurement site in the 2010 sample year.

### 40

### 41 

# 6.0 Data Trends

This section provides an overa ll description of the pollutants currently collected and provides trends for O 3 

### , PM 10 

### and PM 2.5 

### in Pinal County. Appendix C of the document includes a complete data set for each pollutant.

In order to discuss this information, it is necessary to clarify the dual meanings for the word “exceedance”. The common understanding, an exceedance occurs whenever a value exceeds a reference value. However, for purposes of defining what constitutes a violation of several of the ambient air quality sta ndards, relevant EPA regulations define “exceedances” as discrete events, and the various standards define a violation as respectively occurring when either the actual or the expected number of exceedances is greater than one per year.

In contrast, all other ambient air quality standards rely on numerical averaging to define what complies with or violates the standa rd. For those standards, a monitored value above the defined standard may contribute towa rd an average that violates the standard, but that monitored value does not constitute an “exceedance” in a regulatory sense.

In the case of the eight-hour ozone sta ndard, the first three observed eight-hour concentrations above the standard reference va lue are not even considered for purposes of determining compliance, and only the fourth high value counts towards the calculated average that may violate the standard. This document will use the term excursion to denote values that are greater than a numerical aver aging standard.

### 42 6.1 Carbon Monoxide

Carbon m onoxide is a tastele ss, odorless, colorless gas that competes with oxygen in the bloodstream. Carbon monoxide binds to hem oglobin in the bloodstream and thereby impairs oxygen transport. This decrease in oxygen transport can result in a reduction of exercise tolerance, an increase in the visual threshold for light awareness, headaches, and dizziness.

The largest source of carbon monoxide is vehi cles, which produce th e pollutant through the incomplete combustion of fuels. Elev ated levels generally occur near major intersections where large numbers of vehi cles pass through at a slow rate. Peak concentrations are generally recorded between November and February. This is caused by vehicles producing more carbon monoxide in cold weather and the inversion conditions at this time of year trapping a stab le and stagnate layer of air near the earth’s surface.

The carbon monoxide NAAQS has two forms, a one-hour standard of 35 ppm, and an eight-hour standard of 9 ppm.

Carbon Monoxide monitoring was discontinued at the Apache Junction and Casa Grande sites as of May of 2002 and October of 2002, respectively.

Between 1996 and 2002, the highest one-hour averag e recorded at eith er monitoring site was approximately 10% of the standard and the highest eight-hour average recorded was approximately 15% of the standa rd. Considering the relatively low levels and to better utilize resources, the carbon monoxide monitors were discontinued. If the NAAQS or conditions change and carbon monoxide mon itoring is potentially required, Pinal County will evaluate the possibility of resuming data collection.

Carbon Monoxide data summaries are presented in Appendix C.

### 43 6.2 Ozone

Ozone can be found both as a natural component of the atm osphere and as a pollutant. The ozone layer located in the stratosphere, ap proximately eight to thirty miles above the earth’s surface, absorbs harm ful ultraviolet radiation befo re it can reach the earth’s surface. The ozone found at the earth’s surf ace is a pollutant produced through chemical reactions that involve volatil e organic compounds, nitrogen oxides, and sunlight. Sources of volatile organic compounds include vehi cles and other gasoline powered motors, industrial processes, and biogenic emissions from plants. Sources of nitrogen oxides include vehicles, construction equipment, trai ns, electric power plan ts, industrial sources, and biogenic emissions from soil. Exposure to elevated ozone concentrations leads to impaired lung function in humans and plan t damage by impairing plant respiration.

The official ozone season in Arizona, as de fined by EPA, is January through Decem ber. Many ozone monitors in Arizona operate year round, however when reviewing historic ozone data it can be seen that the highes t concentrations generally occur during the months of April through October when temper atures are highest. In Section 2.5, Ozone Season Definition, a request and justification ar e presented to designate the Pinal County ozone season to be April through October.

Refer to Section 1.0 for a deta iled description of the ozone standards and Appendix C for 1-hour and 8-hour data summaries.

The following subsections discuss the ozone trends in Pinal County. Generally, Pinal County easily meets the former one-hour standa rd, but some areas approach the revised eight-hour standard. Refer to Appendix C fo r county-wide one-hour and eight-hour ozone data.

### 44 6.2.1 One-Hour Ozone

Pinal County m et the former one-hour ozone standard. Even though this standard has been revoked, one-hour ozone data will continue to be reported in this document to assess trends. A single exceedance of the one-hour st andard was recorded in Apache Junction in 1995 but was not a violation because the sta ndard allowed one exceedance per calendar year. No exceedances of the 1-hour standard were recorded at Casa Grande, Queen Valley, Combs, Maricopa, or Pinal Air Park.

Given the still modest level of urban and i ndustrial development in most of Pinal County, conjecture supports a conclusi on that a large portion of the ozone recorded at these six sites is a result of transport from the Phoe nix urban area or elsewhere. Daily maximum one-hour averages at Apache junction and Queen Valley in 2008 were among the highest downwind of the Phoenix metropolitan area, The sites recorded concen trations of 98 and 99 PPB, respectively. In other locations the 1 hour average ozone concentrations have generally decreased over time. Several site s show an increase in 2008 over the previous year. In general, the long term trend is downward as evident with Casa Grande and Apache Junction, the two long term sites.

Figure 6-1 shows the one-hour maximum read ings recorded at Apache Junction, Casa Grande, Queen Valley, Combs, Maricopa, and Pinal Air Park.

Figure 6-1: One-Hour Ozone T rends – Maximum Concentration

60 75 90 105 120 135

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

Yearppb

1 Hour Standard - revoked Apache Junction 1 Hour Max Casa Grande

Combs Maricopa Pinal Air Park Queen Valley

### 45 6.2.2 Eight-Hour Ozone

As with the 1-hour averages shown above, c onjecture supports a c onclusion that a large portion of the ozone recorded at these six sites is a result of transport from the Phoenix urban area or elsewhere. Daily maximum 8-hour averages remain elevated at Apache Junction and Queen Valley. In general, th e 8-hour average ozone concentrations have decreased over time at the two long term s ites, Apache Junction and Casa Grande. Many of the sites show an increas e in 2008 which is also reflected in the 1-hour average concentrations. Overall, 2006 was a high ozone year across all networ ks in Arizona with 2008 very close at most Pinal County sites.

Figure 6-2 shows the fourth highest eight-hour average r ecorded at Apache Junction, Casa Grande, Queen Valley, Combs, Maricopa, and Pinal Air Park.

Figure 6-2: Eight-Hour Ozone Trends – 4 th 

### Highest Concentration

50 55 60 65 70 75 80 85 90 95

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

Yearppb

8 Hour Standard 1997-2007 8 Hour Standard 2008 Apache Junction Casa Grande Combs Maricopa Pinal Air Park Queen Valley

### 46 6.3 Particulate Matter smaller than 10 microns (PM 10 

### )

PM 10 

### is airborne particles less than or equal to ten microns (1 micron = 10 -4 

### centimeters) in diameter. PM 10 

### can result from many sources, such as re-entrained dust from vehicles traveling on paved roads, vehicles traveli ng on unpaved roads, earth moving activities, bulk material handling, wind blown dust, a nd combustion processes, notably power plants and diesel engines.

When particulate matter is inhaled into the re spiratory tract the heal th effects depend on the size of the particle. Particles larger than ten microns are genera lly removed from the respiratory system by sneezing. Particles betwee n five microns and ten microns in size can either be removed from the respir atory system by sneezing or moved up the respiratory tract by cilia (hai r like projections) in the lung. Once the particulates have been moved back up the respiratory tract th ey may be swallowed and absorbed in the gastrointestinal tract, where they may be ex creted. Particles ranging from two microns to five microns are generally deposited deeper in to the respiratory tract. Still, cilia action has the potential to move the particles back up the respiratory tract, where they may be swallowed and absorbed in the gastrointes tinal track. Particulates smaller than two microns may reach an area of the lung called th e alveolar region. This is the region of the lung where absorption into the bloodstream is most likely.

Refer to section 1.0 for a detailed description of the PM 10 

### standards and Appendix C for a summary of PM 10 

### data collected throughout Pinal County.

The following subsections discuss the values, trends and contributing sources for each PM 10 

### monitoring site. The data presented here reflects the applicati on of Pinal County’s Natural Events Action Plan (NEAP). Gene rally, the Pinal County NEAP allowed for exclusion of data where the elevated particulate concentr ations resulted from certain defined high wind conditions.

An initial Pinal County NEAP was adopted in 1997. Underlying EPA guidance calls for a five-year review of such a plan. In 2002 Pi nal County Air Quality proposed to renew the existing NEAP. Although EPA did not comment on the 1997 Pinal County NEAP, the EPA expressed a number of concerns as part of the review process in 2002. As a result of the review, the EPA informed Pinal County Air Quality that it would not approve a NEAP for the area at this time. The data included in this document invokes the 1997 NEAP in reporting data through the five-y ear anniversary date of December 5, 2002. However, none of the data collected after th is date has been subjected to the 1997 NEAP.

In 2006 ADEQ initiated a NEAP program to id entify regional wind blown events, or natural events that resulted in elevated PM 10 

### concentrations. Pi nal County continuous PM 10 

### TEOM data was reviewed as part of th is process. When a regional wind blown event was identified as a contributor to elevated PM 10 

### concentrations or exceedances, the continuous TEOM data was submitted to the EP A Region IX office for concurrence. The EPA did not concur that the 2006 Pinal County data should be flagge d as a natural event since Best Available Control Measures (BAC M) were not implemented in Pinal County during this time period. The data pres ented in this document includes all PM 10 

### concentrations recorded in 2006; the natural events have not been removed.

### 47 In March of 2007 EPA replaced the Natural Ev ents Action P lan with the Treatment of Data Influenced by Exceptional Events Rule. This new rule allows monitoring agencies to submit documentation to EPA that shows an exceedance would not have occurred “but for” the exceptional event. Pinal County Air Quality submitted an Exceptional Events package to EPA asking that thirty two events be excluded from the 2007 PM 10 

### data set and will submit a 2008 package consisting of sixteen events. The 2007 and 2008 Exceptional Events package asserts that the exceedances listed in the package would not have occurred “but for” the exceptional events (namely elevated wind speeds). If EPA concurs with Pinal County Air Quality’s conclusion that these are exceptional events the exceedances listed in the package will be excl uded from the data set used for determining compliance with the NAAQS. This document does not exclude any of the 2007 or 2008 PM 10 

### exceedances since EPA has yet to concur with our assertions.

### 48 6.3.1 24-Hour PM 10 

### Trends

Figure 6-3, 6-4a, and 6-4b illustra te maximum 24-hour average PM 10 

### values collected throughout Pinal County. To better illustrate th e range in concentrations the figures are separated into two categories, highest a nd lowest concentration sites. Maximum PM 10 

### concentrations typically vary from year to y ear because they result from local sources or
events.

Figure 6-3 shows trends at the highest concentration sites; Stanfield, City of Maricopa, Pinal County Housing, and Cowtown. It is ev ident from the illustration that the each of the sites has recorded 24- hour average concentrati ons in excess of the PM 10 

### standard of 150μg/m 3 

### .. In this figure Stanfield has the long est record and a general trend towards higher concentrations over time, pa rticularly in recent years.

Note that for 2007 and 2008 days flagged as exceptional event by Pinal County were not removed from the data set. The events ar e pending concurrence from EPA Region IX. The Casa Grande continuous PM 10 

### TEOM sampler is included in this group since inclusion of the natural event data results in the monitoring exceeding the standard.

Figure 6-3: Maximum 24-Hour PM 10 

### Concentration at Highest Sites

0 250 500 750 1000 1250 1500 1750 2000 2250 2500

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Standard City of Maricopa (TEOM) Stanfield (HiVol) Stanfield (47mm) Stanfield (TEOM) Pinal County Housing East (HiVol) Pinal County Housing (TEOM) Cowtown (47mm) Cowtown (TEOM) Casa Grande (TEOM) Combs (TEOM)



### Figures 6-4a and 6-4b show 24-hour trends fo r sites with concentr ations less than the standard. Apache Junction and the Casa Grande filter based data, shown in figure 6-4a, are below the standard for the period of record. Eloy and Mammoth filter based data, shown in figure 6-4b, show rather large reductions in 2004.

### 49 Figure 6-4a: Maximum 24-Hour PM 10 

### Concentration - Lowest Sites Group A

0 25 50 75 100 125 150 175 200

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Standard Apache Junction Fire Station (HiVol)

Apache Junction North (HiVol) Apache Junction South (HiVol)
Casa Grande (HiVol)



### Figure 6-4b: Maximum 24-Hour PM 10 

### Concentration - Lowest Sites Group B

0 25 50 75 100 125 150 175 200

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Standard Coolidge (HiVol) Eloy (HiVol)

Mammoth (HiVol) Pinal Air Park (HiVol) Riverside (HiVol)

### 50 6.3.2 Annual PM 10 

### Trends

Figure 6-5, 6-6a, and 6-6b illu strate annual average PM 10 

### values collected throughout Pinal County. To better illustrate the range in concentrations the figures are separated into regional categories, Wester n sites, Central and Southern sites, and Eastern sites. Annual averages are no longer comparable to a Federal standard, but offer a valuable measure for trend analysis. Before bei ng revoked the annual standard was 50μg/m 3



### . Figure 6-5 shows trends at the highest western sites; Stanfield and City of Maricopa. Of these sites Stanfield has the longest data record. Although the collection method changed in 2006, the increasing trend at Stanfield is evident. Annual averages in the mid-1990s were between 30 and 40μg/m 3 

### compared to values ranging from 80 to 90 μg/m 3 

### in 2006 and 2007. The trend during 2008 showed a slight decrease over 2007. Annual averages at Maricopa are comparable to Stanfiel d, but lack a longer term record.

Figure 6-5: Annual PM 10 

### Average at Western Sites

10 20 30 40 50 60 70 80 90 100

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Annual Standard City of Maricopa (TEOM) Stanfield (HiVol)

Stanfield (47mm) Stanfield (TEOM)



### The Central and Southern sites, shown in Figure 6-6, include Casa Grande, Coolidge, Eloy, Pinal County Housing, and Pinal Air Park. Among these sites Pinal County Housing records the highest concentrations, ab ove the revoked annual standard. All sites in this group show a generally increasing tr end from a rather low year in 2004 through 2007. In 2008 a slight reduction in annual av erage is observed across all monitors.

### 51 Figure 6-6: Annual PM 10 

### Average at Central and Southern Sites

10 20 30 40 50 60 70 80 90 100

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Annual Standard Casa Grande (HiVol) Casa Grande (TEOM) Coolidge (HiVol) Eloy (HiVol) Pinal Air Park(HiVol) Pinal County Housing West ( HiVol) Pinal County Housing East ( HiVol) Pinal County Housing (TEOM)



### The Eastern sites, shown in Figure 6-7, in clude Apache Junction, Combs, Mammoth and Riverside. PM 10 

### measurement at Combs was added during the spring of 2007 therefore the first complete year of data is for 2008. Du ring the first full year of data collection, the average concentration was 56.4μg/m 3 

### at Combs School Apache Junction, Mammoth and Riverside are all well below the revoked annual standard. A longer term trend is apparent with Apache Junction and Mammoth both s howing decreasing values since 2000.

Figure 6-7: Annual PM 10 

### Average at Northern and Eastern Sites

10 20 30 40 50 60 70 80 90 100

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Annual Standard Apache Junction North Apache Junction South Apache Junction Fire Station Combs (TEOM) Riverside

Mammoth

### 52 Because the values at Cowtown are a factor of 2 to 3 higher than other sites, the site is shown alone in Figure 6-8. Annual concentr ations are 4 to 5 times higher than the revoked standard. The 5 year trend at Cowt own shows a slight decrease in 2004 followed by a gradual increase in 2005 and 2006. Th e 2007 and 2008 averages show a moderate decrease in concentration.

Figure 6-8: Annual PM 10 

### Average at Cowtown

0 50 100 150 200 250 300 350

2002 2003 2004 2005 2006 2007 2008ug/m3

Annual Standard Cowtown (47mm) Cowtown (TEOM)

### 53 6.4 Particulate Matter smal ler than 2.5 microns (PM 2.5 

### )

PM 2.5 

### is airborne particles less than or equal to 2.5 microns (1 micron = 10 -4 

### centimeters) in diameter. PM 2.5 

### can result from the combustion of fuels in motor vehicles, power generation, industrial processes, and from burning wood in residential fireplaces. As explained in Section 6.3, the health effects of inhaling pa rticulate matter depends on the size of the particle. PM 2.5 

### particles are small enough to re ach an area of the lung called the alveolar region. This is the region of the lung where absorption into the bloodstream is most likely. Elevated PM 2.5 

### levels may aggravate resp iratory and cardiopulmonary problems.

Refer to section 1.0 for a detailed description of the PM 2.5 

### standards and Appendix C for a summary of PM 2.5 

### data collected throughout Pinal County.

Special considerations for comparing PM 2.5 

### data to the standard are described at 40 CFR Subpart D (58.30). The subpart states that PM 2.5 

### sites with unique-middle scale or microscale representation and hot-spot sites are on ly eligible for comparison to the 24-hour PM 2.5 

### standard. The Cowtown site is characteri zed as a “local hot spot” site according to this definition and can only be used for comparison to the 24-hour PM 2.5 

### standard.

### 54 6.4.1 PM 2.5 

### 24-Hour Trends

Figure 6-9 illustrates 98 th 

### percentile PM 2.5 

### values collected at Apache Junction, Casa Grande, and Cowtown. It is evident from the illustration that the Apache Junction and Casa Grande sites are below the standard ove r the period of recor d. Both sites show a concentration general ra nge between 15 and 20μg/m 3 

### with the exception of 2003 when values were slightly higher. A slight incr ease is also apparent in 2007. The 2008 values are inline with those r ecorded in 2007. The 24-Hour values at Casa Grande are typically higher than Apache Junction by approximately 25%.

The Cowtown site shows values above 35μg/m 3 

### over the 3 years it has been in operation. The three year average of the 98 th 

### percentile value dropped from 60μg/m 3 

### in 2007 to 48 in μg/m 3 

### in 2008. The site violates the PM 2.5 

### 24-hour NAAQS even after the decrease in concentration.

Figure 6-9: Network-Wide 24-Hour Average PM 2.5 

### Trends

0 10 20 30 40 50 60 70 80 90

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Standard 1999-2006 Standard 2007 Apache Junction Casa Grande Cowtown

### 55 6.4.2 PM 2.5 

### Annual Trends

Figure 6-10 illustrates annual average PM 2.5 

### values collected at Apache Junction and Casa Grande. Both sites show concentra tions with a range between 5 and 10μg/m 3 

### with the exception of 2003 when values were slightly higher. A slight increa se is also apparent in 2007 and 2008. As with seen in the 24-Hour averages, the values at Casa Grande are typically higher than Apache Junction by approximately 25%.

As described in the introduction to this sec tion, Cowtown is not compared to the annual standard.

Figure 6-10: Network-Wi de Annual Average PM 2.5 

### Trends

0 2 4 6 8 10 12 14 16

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008ug/m3

Standard Apache Junction Casa Grande

### 56

### 57 

# Appendix A

Acronyms & Abbreviations

### 58

### 59 Acronyms & Abbreviations used in this document

ADT Average Daily Traffic AQS Air Quality System ADEQ Arizona Department of Environmental Quality ARM Approved Regional Method BACM Best Available Control Measures CAA Clean Air Act CASAC Clean Air Scientific Advisory Committee CFR Code of Federal Regulations CO Carbon Monoxide EPA Environmental Protection Agency FDMS Filter Dynamics Measurement System FEM Federal Equivalent Methods FRM Federal Reference Methods HiVol High Volume PM 10 

### sampler IMPROVE Interagency Monitoring of Protected Visual Environments MET Meteorological MSA Metropolitan Statistical Area N/A Not Applicable NAAQS National Ambient Air Quality Standards NEAP Natural Events Action Plan NO 2 

### Nitrogen Dioxide O 3 

### Ozone PAMS Photochemical Assessment Monitoring Station PCAQCD Pinal County Air Quality Control District Pb Lead PM 10 

### Particulate Matter less than or equal to 10 microns PM 2.5 

### Particulate Matter less th an or equal to 2.5 microns ppm Parts Per Million ppb Parts Per Billion PSD Prevention of Significant Deterioration QAPP Quality Assurance Project Plan R&P Rupprecht and Patashnick SLAMS State and Local Air Monitoring Stations SO 2 

### Sulfur Dioxide SPM Special Purpose Monitor TEOM Tapered Element Oscillating Microbalance

μ g/m 3 

### Micrograms per Cubic Meter

### 60

### 61 

# Appendix B

PCAQCD Monitoring Site Descriptions

### 62

### 63 Apache Junction Fire Station – AJFS AQS Site ID: 04-021-3002 3955 E. Superstition Blvd. TE, Apache Junction, Arizona Latitude: 33.421194° Longitude: -111.503222 o Map Datum: WGS 84

Table B-1 Apache Junction Fire Station (AJFS)

Parameter Instrumen t #1 Instrument #2 Instrument #3 Pollutant Type PM 10 PM 2.5 PM 2.5 Date Established 2003 1999 1999 County ID AJ AJE AJW Sampler Make & Model Wedding HiVol R&P 2025 Andersen RAAS2.5-100
Classification SLAMS SLAMS SPM Scale Neighborhood Neighborhood Neighborhood Objective Population Population Population Inlet Height 3.5 meters 3.7 meters 3.5 meters Distance from Tree Dripline 21.2 me ters 25.7 meters 24.2 meters Obstacle Description None None None Height of Obstacle N/A N/A N/A
Distance and Direction N/A N/A N/A
Airflow Arch 360 o 360 o 360 o

Furnace or Incinerator Flue None None None
Distance and Direction N/A N/A N/A
Distance between Collocated Samplers 5.9 meters 1.5 meters 1.5 meters

Nearest Road Arroya Arroya Arroya
Distance and Direction to Road 43.6 meters - NE 38.1 meters - NE 39.6 meters - NE Traffic Count (ADT) 17 cars per day 17 cars per day 17 cars per day
Schedule 1 in 6 days 1 in 3 days Backup only Surrounding Area Residential / Desert Residential / Desert Residential / Desert
Site Groundcover Gravel / Vegetative Gravel / Vegetative Gravel / Vegetative Frequency of flow rate verifications Quarterly Monthly Monthly
Last two flow rate audits current current N/A Does Site Meet App D&E Criteria Yes Yes Yes

Notes: The photo was taken while facing west.

### 64 Apache Junction Maintenance Yard -AJ AQS Site ID: 04-021-3001 305 E. Superstition Blvd., Apache Junction, Arizona Latitude: 33.4214 o Longitude: -111.5436 o ' Map Datum: WGS 84

Table B-2 Apache Junction Maintenance Yard (AJ)

Parameter Instrument #1 Instrument #2 Instrument #3 Pollutant Type O 3 Wind Temp & RH / Pressure

Date Established 1992 1993 1994 County ID AJ O 3 AJ MET AJ MET Sampler Make & Model API 400 RM Young 05305 AQ Vaisala HMP 45C/CS105

Classification SLAMS N/A N/A Scale Neighborhood / Urban N/A N/A Objective Population / Transport N/A N/A Inlet Height 3 meters 10 meters 3 meters Distance from Tree Dripline 12 meters 20 meters 12 meters Obstacle Description Building None Building Height of Obstacle 4 meters N/A 4 meters

Distance and Direction 5meters –SW N/A 5 meters-SW

Airflow Arch 280 o 360 o 280 o

Furnace or Incinerator Flue None None None
Distance and Di rection N/A N/A N/A

Distance between Collocated Samplers N/A N/A N/A

Nearest Road Hwy 88 Hwy 88 Hwy 88

Distance and Direction to Road 35 meters - E 27meters - E 35 meters - E Traffic Count (ADT) 3848 cars per day 3848 cars per day 3848 cars per day

Schedule Continuous Continuous Continuous

Probe Material Glass N/A N/A

Residence Time > 20 sec N/A N/A Surrounding Area Gravel lot Gravel lot Gravel lot

Site Groundcover Gravel Gravel Gravel Frequency of one point QC check Bi-weekly N/A N/A Last annual performance evaluation current N/A N/A Does Site Meet App D& E Criteria Yes N/A N/A
Notes: The photo was taken while facing west.

### 65 Casa Grande Airport - CGA AQS Site ID: 04-021-3003 660 W. Aero Dr., Casa Grande, Arizona Latitude: 32.954361 o Longitude: -111.76225 o Map Datum: WGS 84

Table B-3 Casa Grande Airport (CGA)

Parameter Instrument #1 Instrument #2 Instrument #3 Pollutant Type O 3 Wind Temp & RH/Pressure

Date Established 1991 1991 1994 County ID CG O 3 CG MET CG MET Sampler Make & Model API 400E RM Young 05305AQ Vaisala HMP 45C/CS105

Classification SLAMS N/A N/A Scale Neighborhood/Regional N/A N/A Objective Population/Transport N/A N/A Inlet Height 4.1 meters 11.8 meters 3.2 meters Distance from Tree Dripline 8.1 meters None None Obstacle Description Tower Tower Tower Height of Obstacle 14 meters 14 meters 14 meters

Distance and Direction 6 meters - N Adjacent 6 meters - N

Airflow Arch 360 o 360 o 360 o

Furnace or Incinerator Flue None None None
Distance and Di rection N/A N/A N/A

Distance between Collocated Samplers N/A N/A N/A

Nearest Road Aero Dr. Aero Dr. Aero Dr.

Distance and Direction to Road 22 meters - W 22 meters - W 22 meters - W Traffic Count (ADT ) Not Available Not Available Not Available

Schedule Continuous Continuous Continuous

Probe Material Glass N/A N/A

Residence Time > 20 sec N/A N/A Surrounding Area Parking Lot / Tarmac Parking Lot / Tarmac Parking Lot / Tarmac

Site Groundcover Pavement Pavement Pavement Frequency of one point QC check Bi-weekly N/A N/A Last annual performance evaluation current N/A N/A Does Site Meet App D& E Criteria Yes N/A N/A
Notes: The photo was taken while facing northeast.

### 66 Casa Grande Downtown – CGD AQS Site ID: 04-021-0001 401 Marshall St., Casa Grande, Arizona Latitude: 32.877583 o Longitude: -111.752222 o Map Datum: WGS 84

Table B-4 Casa Grande Downtown (CGD)

Parameter Instrument #1 Instrument#2 Instrument #3 Instrument #4 Pollutant Type PM 10 PM 2.5 PM 2.5 PM 10 Date Established 1989 1999 2007 2007 County ID CG PM 10 CG (N) PM 2.5 CG (S) PM 2.5 CG Downtown PM 10 Sampler Make & Model R&P 2000-H R&P 2000-H R&P 2000-H R&P 1400a (A/B)
Classification SLAMS SLAMS SLAMS SPM Scale Neighborhood Neighborhood Neighborhood Neighborhood Objective Population Popula tion Population Population Inlet Height 6.0 mete rs 6.1 meters 6.0 meters 6.0 meters Distance from Tree Dripline 19.6 meters 16.4 meters 19.0 me ters 24.8 meters Obstacle Description N one None None None Height of Obst acle N/A N/A N/A N/A
Distance and Dire ction N/A N/A N/A N/A
Airflow Arch 360 o 360 o 360o 360o
Furnace or Incinerator Flue Furnace Flue Furnace Flue Furnace Flue Furnace Flue
Distance and Direction 5.6 meters - S 7.6 meters - S 4.8 meters - S 9.8 meters - S
Distance between Collocated Samplers 3.3 meters 2.8 meters 2.8 meters 2.8 meters

Nearest Road Marshall St. Marshall St. Marshall St. Marshall St.
Distance and Direction to Road 20.6 meters – E 18.4 meters – E 19.5 mete rs - E 20.1 meters - E Traffic Count (ADT) Not available Not available Not available Not available
Schedule 1 in 6 days 1 in 6 days 1 in 6 days Continuous Surrounding Area Business District Business District Business District Business District
Site Groundcover Pavement Pa vement Paveme nt Pavement Frequency of flow rate verifications Quarterly Monthly Monthly Bi-weekly
Last two flow rate audits cu rrent current current current Does Site Meet App D&E Criteria Yes Yes Yes Yes
Notes: The photo was taken while facing northeast.

### 67 Combs School – CB AQS Site ID: 04-021-3009 301 E. Combs Rd., Queen Creek, Arizona Latitude: 33.219111 o Longitude: -111.561111 o Map Datum: WGS 84

Table B-5 Combs School (CB)

Parameter Instrument #1 Instrument #2 Pollutant Type O 3 PM 10 Date Established 2002 2007 County ID CB COMBS PM 10 Sampler Make & Model API 400E R&P 1400a (A/B)

Classification SPM SPM Scale Neighborhood / Regiona l Neighborhood / Regional Objective Population / Trans port Population / Transport Inlet Height 4.9 me ters 4.5 meters Distance from Tree Dripline 22.9 meters 22.9 meters Obstacle Description Playgr ound Canopy School Building Height of Obstacle 4.5 meters 4.0 meters

Distance and Direction 4. 3 meters - S 7.2 meters - N
Airflow Arch 360 o 360 o

Furnace or Incinerator Flue None None
Distance and Direction N/A N/A Distance between Collocated Samplers N/A N/A

Nearest Road Combs Rd. Combs Rd.

Distance and Direction to Road 89.5 meters - N 89.5 meters - N Traffic Count (ADT) 2459 cars per day 2459 cars per day

Schedule Continuous / Seasonal Continuous

Probe Material Glass N/A

Residence Time > 20 sec N/A Surrounding Area School Grounds / Reside ntial School Grounds / Residential

Site Groundcover Concrete / Dirt Road Concrete / Dirt Road Frequency of flow rate ve rifications N/A Bi-weekly

Last two flow rate audits N/A Recently Installed Frequency of one point QC check Bi-weekly N/A Last annual performance ev aluation current current Does Site Meet App D&E Criteria Yes Yes

Notes: The picture was taken facing southwest.

### 68 Coolidge Maintenance Yard – CL DG AQS Site ID: 04-021-3004 212 E. Broadway, Coolidge, Arizona Latitude: 32.978556 o Longitude: -111.514833 o Map Datum: WGS 84

Table B-6 Coolidge Maintenance Yard (CLDG)

Parameter Instrument #1 Pollutant Type PM 10 Date Established 1992 County ID CLDG Sampler Make & Model Wedding HiVol
Classification SLAMS Scale Neighborhood Objective Population Inlet Height 3.4 meters Distance from Tree Dripline None Obstacle Description Building Height of Obstacle 3.2 meters
Distance and Direction 5.7 meters - NE
Airflow Arch 360 o
Furnace or Incinerator Flue None
Distance and Direction N/A
Distance between Collocated Samplers N/A

Nearest Road Pacific St.
Distance and Direction to Road 7.9 meters – W Traffic Count (ADT) 164 cars per day
Schedule 1 in 6 days Surrounding Area Residential
Site Groundcover Gravel / Vegetative Frequency of flow rate verifications Quarterly
Last two flow rate audits current Does Site Meet App D&E Criteria Yes

Notes: The photo was taken facing north.

### 69 Cowtown Road – CWTN AQS ID: 04-021-3013 1.1 37580 W. Maricopa-Casa Grande Highway, Maricopa, Arizona

Latitude: 33.01053 Longitude: -111.97205 o Map Datum: WGS 84

Table B-7 Cowtown Road (CWTN)

Parameter Instrument #1 Instrument #2 Instrument #3 Pollutant Type PM 10 PM 10 PM 2.5 Date Established 2001 2005 2005 County ID CWTN TEOM CW TN PM10 CWTN PM2.5 Sampler Make & Model R&P 1400a (A/B) R&P 2000-H R&P 2000-H
Classification SPM SPM SPM
Scale Microscale Microscale Microscale Objective Population/Source Im pact Population/S ource Impact Popula tion/Source Impact Inlet Height 3.2 meters 3.4 meters 3.4 meters Distance from Tree Dripline None None None Obstacle Description None None None Height of Obstacle N/A N/A N/A
Distance and Di rection N/A N/A N/A
Airflow Arch 360 o 360o 360o
Furnace or Incinerator Flue None None None
Distance and Di rection N/A N/A N/A
Distance between Collocated Samplers 0.7 meters 1.6 me ters 1.6 meters

Nearest Road Casa Grande-Maricopa Hwy Casa Grande-Maricopa Hwy Casa Grande-Maricopa Hwy
Distance and Direction to Road 53.6 me ters - S 65.5 meters - S 65.5 meters - S Traffic Count (ADT) 2717 cars per day 2717 cars per day 2717 cars per day
Schedule Continuous 1 in 6 days 1 in 6 days Surrounding Area Agricultural / Feedlots Agricu ltural / Feedlots Agri cultural / Feedlots
Site Groundcover Vegetativ e Vegetative Vegetative Frequency of flow rate verifica tions Bi-weekly Monthly Monthly
Last two flow rate audits current current current Does Site Meet App D& E Criteria Yes Yes Yes
Notes: The picture was taken facing east.

### 70 Table B-7 continued Cowtown Road (CWTN)

Parameter Instrument #4 Instrument #5 Pollutant Type Wind Temp&RH/Pressure
Date Established 2002 2002 County ID CWTN MET CWTN MET Sampler Make & Model RM Young 05305 AQ Viasala HMP35C/PTA427
Classification N/A N/A
Scale N/A N/A Objective N/A N/A Inlet Height 3.5 meters 2.9 meters Distance from Tree Dripline None None Obstacle Description None None Height of Obstacle N/A N/A
Distance and Direction N/A N/A
Airflow Arch 360 o 360 o
Furnace or Incinerator Flue None None
Distance and Direction N/A N/A
Distance between Collocated Samplers N/A N/A

Nearest Road Casa Grande-Maricopa Hwy Casa Grande-Maricopa Hwy
Distance and Direction to Road 53.6 meters - S 53.6 meters - S

Traffic Count (ADT) 2717 cars per day 2717 cars per day
Schedule Continuous Continuous Surrounding Area Agricultural / Feedlots Agricultural / Feedlots
Site Groundcover Vegetative Vegetative Frequency of flow rate verifications N/A N/A

Last two flow rate audits N/A N/A Does Site Meet App D&E Criteria N/A N/A

### 71 Eloy County Complex - ELY AQS Site ID: 04-021-3014 801 N. Main St, Eloy, Arizona Latitude: 32.757639 o Longitude: -111.554861 o Map Datum: WGS 84

Table B-8 Eloy County Complex (ELY)

Parameter Instrument #1 Pollutant Type PM 10 Date Established 2007 County ID ELY Sampler Make & Model Andersen HiVol
Classification SLAMS Scale Neighborhood Objective Population Inlet Height 5.2 meters Distance from Tree Dripline N/A Obstacle Description None Height of Obstacle N/A
Distance and Direction N/A
Airflow Arch 360 o

Furnace or Incinerator Flue None
Distance and Direction N/A Distance between Collocated Samplers N/A
Nearest Road Main St.
Distance and Direction to Road 31.0 meters – W Traffic Count (ADT) Not available
Schedule 1 in 6 days Surrounding Area Resi dential / Business
Site Groundcover Pavement Frequency of flow rate verifications Quarterly
Last two flow rate audits current Does Site Meet A pp D&E Criteria Yes
Notes: The picture was taking facing east.

### 72 Mammoth County Complex -MAM AQS Site ID: 04-021-3006 118 S. Catalina, Mammoth, Arizona Latitude: 32.719639 o Longitude: -110.643 o Map Datum: WGS 84

Table B-9 Mammoth County Complex (MAM)

Parameter Instrument #1 Pollutant Type PM 10 Date Established 1995 County ID MAM Sampler Make & Model Andersen HiVol
Classification SLAMS Scale Neighborhood Objective Population / Background Inlet Height 5.0 meters Distance from Tree Dripline 10.8 meters Obstacle Description None Height of Obstacle N/A
Distance and Direction N/A
Airflow Arch 360 o

Furnace or Incinerator Flue Furnace
Distance and Direction 5 meters – W Distance between Collocated Samplers N/A
Nearest Road Catalina St.
Distance and Direction to Road 18.9 meters – SE Traffic Count (ADT) Not available
Schedule 1 in 6 days Surrounding Area Residential
Site Groundcover Pavement Frequency of flow rate verifications Quarterly
Last two flow rate audits current Does Site Meet A pp D&E Criteria Yes
Notes: The picture was taken facing north.

### 73 (City of) Maricopa County Complex - MCPA AQS Site ID: 04-021-3010 44625 W. Garvey Rd., Maricopa, Arizona Latitude: 33.058972 o Longitude: -112.046917 o Map Datum: WGS 84

Table B-10 (City of) Ma ricopa County Complex (MCPA)

Parameter Instrument #1 Instrument #2 Pollutant Type O 3 PM 10 Date Established 2002 2005 County ID MCPA O 3 MCPA PM 10 Sampler Make & Model API 400 R&P 1400a (A/B)

Classification SPM SPM Scale Neighborhood / Regional Neighborhood Objective Population / Transport Population Inlet Height 3.9 me ters 3.1 meters Distance from Tree Dripline None None Obstacle Description Building Building Height of Obstacle 3.4 meters 3.4 meters

Distance and Direction 6. 3 meters - W 6.3 meters – W

Airflow Arch 360 o 360o

Furnace or Incinerator Flue Furnace Flue Furnace Flue

Distance and Direction 8.2 meters - SW 6.7 meters – SW Distance between Collocated Samp lers 1.4 meters 1.4 meters
Nearest Road Garvey Rd. Garvey Rd.

Distance and Direction to Road 65 meters - W 65 meters - W Traffic Count (ADT) 6787 cars per day 6787 cars per day

Schedule Continuous / Seasonal Continuous

Probe Material Glass N/A

Residence Time > 20 sec N/A Surrounding Area Vacant Lot / Business Vacant Lot / Business

Site Groundcover Gravel / Vege tative Gravel / Vegetative Frequency of flow rate ve rifications N/A Bi-weekly

Last two flow rate audits N/A 4/26/05, 8/15/06 Frequency of one point QC check Bi-weekly N/A Last annual performance evaluation current current Does Site Meet App D&E Criteria Yes Yes
Notes: The picture was taken facing north.

### 74 Pinal Air Park – PP AQS Site ID: 04-021-3007 Water Well #2, Pinal Air Park Rd., Marana, Arizona Latitude: 32.508306 o Longitude: -111.308056 o Map Datum: WGS 84

Table B-11 Pinal Air Park (PP)

Parameter Instrument #1 Instrument #2 Pollutant Type PM 10 O 3 Date Established 1993 2002 County ID PP PM 10 PP O 3 Sampler Make & Model Andersen HiVol API 400
Classification SLAMS SPM Scale Regional Regional Objective Background Transport Inlet Height 4 me ters 4.1 meters Distance from Tree Dripline None None Obstacle Description None None Height of Obstacle N/A N/A
Distance and Direction N/A N/A
Airflow Arch 360 o 360 o

Furnace or Incinerator Flue None None
Distance and Direction N/A N/A Distance between Collocated Samp lers 16.1 meters 16.1 meters
Nearest Road Service blac ktop Service blacktop
Distance and Direction to Road 65 meters – E 54.2 meters – E Traffic Count (ADT) Not available Not available
Schedule 1 in 6 days Continuous / Seasonal
Probe Material N/A Glass
Residence Time N/A > 20 sec Surrounding Area De sert Desert
Site Groundcover Vegetative Vegetative Frequency of flow rate ve rifications Quarterly N/A
Last two flow rate audits current current Frequency of one point QC check N/A Bi-weekly Last annual performan ce evaluation N/A 7/20/06 Does Site Meet App D&E Criteria Yes Yes
Notes: The picture was taken facing southwest.

### 75 Pinal County Housing Complex - PCH AQS Site ID: 04-021-3011 970 N. Eleven Mile Corner Rd., Casa Grande, Arizona Latitude: 32.891056 o Longitude: -111.5705 o Map Datum: WGS 84

Table B-12 Pinal County Housing Complex (PCH)

Parameter Instrument #1 Instrument #2 Instrument #3 Pollutant Type PM 10 PM 10 PM 10 Date Established 2002 2002 2004 County ID PCH TEOM PCHE PM 10 PCHW PM 10 Sampler Make and Model R&P 1400a (A/B) Wedding HiVo l Wedding HiVol
Classification SPM SLAMS SLAMS Scale Neighborhood Neighborhood Neighborhood Objective Population Population Population Inlet Height 2.8 meters 3.0 meters 3.0 meters Distance from Tree Dripline 13.7 me ters 11.6 meters 12.1 meters Obstacle Description Shed Shed Shed Height of Obstacle 2.6 mete rs 2.6 meters 2.6 meters
Distance & Direction 10.2 meters – W 5.9 meters – SW 8.1 meters – SW
Airflow Arch 360 o 360 o 360 o

Furnace or Incinerator Flue None None None
Distance & Direc tion N/A N/A N/A Distance between Collocated Samplers 3.5 meters 2.3 me ters 2.3 meters
Nearest Road Eleven Mile Corner Rd. Eleven Mile Corner Rd. Eleven Mile Corner Rd.
Distance & Direction to Road 400 mete rs – E 400 meters – E 400 meters – E Traffic Count (ADT) 653 cars per da y 653 cars per day 653 cars per day
Schedule Continuous 1 in 6 days 1 in 6 days Surrounding Area Agricultural / Residential Agricultural / Residential Agricultural / Residential
Site Groundcover Gravel / Vegetative Grav el / Vegetative Gr avel / Vegetative Frequency of flow rate verificati ons Bi-weekly Quarterly Quarterly
Last two flow rate audits current current current Does Site Meet App D& E Criteria Yes Yes Yes
Notes: The picture was taken facing north.

### 76 Table B-12 Pinal County Housing Complex (PCH) cont.

Parameter Instrument#4 Instrument #5 Pollutant Type Wind Temp & RH/Pressure
Date Established 2002 2002 County ID PCH MET PCH MET Sampler Make and Model RM Young 05305 AQ Viasala HMP35C/PTA427
Classification N/A N/A
Scale N/A N/A Objective N/A N/A Inlet Height 3.2 me ters 2.8 meters Distance from Tree Dripline 13.7 meters 13.7 meters Obstacle Description Shed Shed Height of Obstacle 2. 6 meters 2.6 meters
Distance & Direction 11.1 me ters – W 10.6 meters – W
Airflow Arch 360 o 360 o

Furnace or Incinerator Flue None None
Distance & Direction N/A N/A Distance between Collocated Samplers N/A N/A
Nearest Road Eleven Mile Corner Rd. Eleven Mile Corner Rd.
Distance & Direction to Road 400 meters – E 400 meters – E Traffic Count (ADT) 653 cars per day 653 cars per day
Schedule Continuous Continuous Surrounding Area Agricultural / Residential Agricultural / Residential

Site Groundcover Gravel / Vege tative Gravel / Vegetative Frequency of flow rate verifications N/A N/A
Last two flow rate audits current current Does Site Meet App D&E Criteria N/A N/A

### 77 Queen Valley - QV AQS Site ID: 04-021-8001 10 S. Queen Anne Dr., Queen Valley, Arizona Latitude: 33.293465 o Longitude: -111.285594 o Map Datum: WGS 84

Table B-13 QueenValley (QV)

Parameter Instrument #1 Instrument #2 Pollutant Type O 3 PM 2.5 , PM 10 Date Established 2001 2001 County ID QV QVA Sampler Make & Model TEI 49C Version II IMPROVE
Classification SPM SPM
Scale Urban Urban Objective Highest Concentration Visibility Inlet Height 4.7 me ters 5.4 meters Distance from Tree Dripline 2.3 meters 6.0 meters Obstacle Description None None Height of Obstacle N/A N/A
Distance and Direction N/A N/A
Airflow Arch 360 o 360 o

Furnace or Incinerator Flue None None
Distance and Direction N/A N/A Distance between Collocated Samp lers 2.1 meters 2.1 meters
Nearest Road Queen Anne Dr. Queen Anne Dr.
Distance and Direction to Road 93 meters – E 93 meters – E Traffic Count (ADT) 785 cars per day 785 cars per day
Schedule Continuous / Seasonal 1 in 3 days Surrounding Area Desert / Reside ntial Desert / Residential
Site Groundcover Vegetative Vegetative Frequency of one point QC check Bi-weekly N/A Last annual performan ce evaluation Unknown* N/A Does Site Meet App D&E Criteria Yes N/A
Notes: The picture was taken facing east. *For add itional detail refer to ADEQ’s State of Arizona Monitoring Network Plan for 2009.

### 78 Riverside Maintenance Yard - RVSD AQS Site ID: 04-021-3012 54964 E. Florence-Kelvin Hwy., Kearny, Arizona Latitude: 33.105806 o Longitude: -110.974194 o Map Datum: WGS 84

Table B-14 Riverside Maintenance Yard (RS)

Parameter Instrument #1 Pollutant Type PM 10 Date Established 2003 County ID RVSD Sampler Make & Model Anderson HiVol
Classification SLAMS Scale Neighborhood Objective Source Impact Inlet Height 3.0 meters Distance from Tree Dripline 10.2 meters Obstacle Description Building Height of Obstacle 3.8 meters
Distance and Direction 8.5 meters - NE
Airflow Arch 360 o

Furnace or Incinerator Flue None
Distance and Direction N/A Distance between Collocated Samplers N/A
Nearest Road Florence-Kelvin Hwy.
Distance and Direction to Road 24.7 meters - E Traffic Count (ADT) 75 cars per day
Schedule 1 in 6 days Surrounding Area Reside ntial / Desert
Site Groundcover Gravel Frequency of flow rate verifications Quarterly
Last two flow rate audits current Does Site Meet A pp D&E Criteria Yes
Notes: The picture was taken facing north.

### 79 Stanfield County Complex - STNF AQS Site ID: 04-021-3008 36697 W. Papago Dr., Stanfield, Arizona Latitude: 32.881194 o Longitude: -111.962 o Map Datum: WGS 84

Table B-15 Stanfield County Complex (STNF)

Parameter Instrument#1 Instrument#2 Instrument#3 Pollutant Type PM 10 PM 10 Video
Date Established 1988 2006 2003 County ID STNF STNF STNF Video Sampler Make & Model Wedding Hi Vol R&P 1400a (A/B) Panasonic
Classification SLAMS SPM AG-6740 Scale Neighborhood Neighborhood N/A Objective Population Population N/A Inlet Height 4.3 meters 4.7 meters 8.2 meters Distance from Tree Dripline None None None Obstacle Description FD E ngine Carport FD Engine Carport None

Height of Obstacle 4. 0 meters 4.0 meters N/A
Distance and Direction 5.9 meters – N 3.1 meters – S N/A
Airflow Arch 360 o 360o 360 o

Furnace or Incinerator Flue None None None
Distance and Di rection N/A N/A N/A Distance between Collocated Samplers N/A 2.3 meters N/A
Nearest Road Navajo Way Navajo Way Navajo Way
Distance and Direction to Road 19 me ters – W 21.2 meters – W 21.2 meters – W Traffic Count (ADT) 91 cars per day 91 cars per day 91 cars per day
Schedule 1 in 6 days 1 in 6 days 1 in 6 days Surrounding Area Residential Residential Residential
Site Groundcover Gravel / Vegetative Gravel / Vegetative Gravel / Vegetative Frequency of flow rate verifi cations Quarterly Bi-weekly N/A
Last two flow rate audits current current N/A Does Site Meet App D& E Criteria Yes Yes Yes

### 80

### 81 

## Appendix C

PCAQCD Ambient Air Monitoring Data

Please refer to Section 1. 0 for a detailed description of the NAAQS for ozone, PM 10 

## and PM 2.5 

## .

### 82

### 83 APACHE JUNCTION CARBON MO NOXIDE DATA (in ppm) 1 HOUR AVERAGES STANDARD: In order to meet the st andard the second highest reading must be less than or equal to 35 ppm.

Table C-1

Year Maximum Reading 2nd Highest Reading Number of Daily Exceedances Number of Sample Hours

1996 2.60 2.60 0 4884 1997 2.20 2.00 0 8675 1998 2.00 2.00 0 8609 1999 1.90 1.70 0 8057 2000 1.48 1.39 0 8543 2001 3.74 3.54 0 6610 2002 a 1.28 1.21 0 3533



### APACHE JUNCTION CARBON MO NOXIDE DATA (in ppm) 8 HOUR AVERAGES STANDARD: In order to meet the st andard the second highest reading must be less than or equal to 9 ppm.

Table C-2

Year Maximum Reading 2nd Highest Reading Number of Daily Exceedances Number of Sample Hours

1996 1.08 1.00 0 4873 1997 1.16 1.01 0 8680 1998 1.28 1.08 0 8613 1999 0.91 0.86 0 8017 2000 0.69 0.69 0 8549 2001 1.06 0.90 0 6633 2002 a 0.79 0.75 0 3552 Footnotes: a - Carbon Monoxide monitoring was discontinued at the Apache Junction site on 5/28/2002. The 2002 readings only represent part of the 2002 carbon monoxide season.

### 84 CASA GRANDE CARBON MONOXIDE DATA (in ppm) 1 HOUR AVERAGES STANDARD: In order to meet the st andard the second highest reading must be less than or equal to 35 ppm.

Table C-3

Year Maximum Reading 2nd Highest Reading Number of Daily Exceedances Number of Sample Hours

1996 1.60 1.50 0 8728 1997 1.50 1.50 0 8595 1998 3.90 3.60 0 8513 1999 2.10 1.50 0 7625 2000 2.45 2.25 0 8416 2001 1.53 1.10 0 8326 2002 a 1.23 1.22 0 6715



### CASA GRANDE CARBON MONOXIDE DATA (in ppm) 8 HOUR AVERAGES STANDARD: In order to meet the st andard the second highest reading must be less than or equal to 9 ppm.

Table C-4

Year Maximum Reading 2nd Highest Reading Number of Daily Exceedances Number of Sample Hours

1996 1.19 1.16 0 8734 1997 1.29 1.11 0 8634 1998 1.46 1.46 0 8525 1999 0.86 0.80 0 7621 2000 0.95 0.84 0 8420 2001 0.77 0.76 0 8355 2002 a 0.81 0.76 0 6745 Footnotes: a - Carbon Monoxide monitoring was discontinued at the Casa Grande site on 10/11/2002. The 2002 readings only represent part of the 2002 carbon monoxide season.

### 85 APACHE JUNCTION OZONE DATA (in ppm) 1 HOUR AVERAGES Table C-5

Year Maximum Reading 2 nd Highest Reading 3 rd Highest Reading 4 th Highest Reading Number of Daily Exceedances Expected Exceedance Rate Number of Sample Hours

1993 0.121 0.110 0.106 0.103 0 0 7654 1994 0.114 0.110 0.108 0.108 0 0 8123 1995 0.136 0.122 0.121 0.114 1 1 7776 1996 0.121 0.115 0.114 0.114 0 0 7832 1997 0.106 0.097 0.096 0.096 0 0 8731 1998 0.112 0.112 0.111 0.106 0 0 8377 1999 0.112 0.111 0.109 0.105 0 0 8447 2000 0.101 0.101 0.098 0.096 0 0 8579 2001 0.101 0.096 0.095 0.092 0 0 8050 2002 0.109 0.097 0.095 0.095 0 0 8199 2003 0.105 0.096 0.094 0.091 0 0 8721 2004 0.084 0.079 0.079 0.079 0 0 8592 2005 0.097 0.089 0.085 0.083 0 0 8694 2006 a 0.106 0.105 0.104 0.095 N/A N/A 8596 2007 a 0.098 0.096 0.095 0.094 N/A N/A 8636 2008 a 0.098 0.094 0.092 0.091 N/A N/A 8724 Footnotes: a - The 1-hour ozone standard was revoked in August 2005. One-hour averages are listed here for trend analysis.



### APACHE JUNCTION OZONE DATA (in ppm) 8 HOUR AVERAGES Table C-6

Year Maximum Reading 2 nd Highest Reading 3 rd Highest Reading 4 th Highest Reading 3 Year Avg of the 4th Highest Number of Daily Excursions Number of Sample Hours 1993 0.086 0.082 0.080 0.080 N/A 1 7654 1994 0.089 0.087 0.085 0.085 N/A 5 8116 1995 0.095 0.093 0.093 0.091 0.085 8 7744 1996 0.092 0.086 0.085 0.085 0.087 6 7801 1997 0.084 0.083 0.082 0.082 0.086 0 8727 1998 0.091 0.089 0.082 0.082 0.083 2 8384 1999 0.091 0.089 0.081 0.080 0.081 2 8459 2000 0.087 0.084 0.082 0.082 0.081 1 8592 2001 0.081 0.081 0.078 0.077 0.079 0 8068 2002 0.081 0.081 0.080 0.079 0.079 0 8220 2003 0.090 0.074 0.072 0.072 0.076 1 8743 2004 0.070 0.070 0.070 0.069 0.073 0 8613 2005 0.076 0.074 0.071 0.068 0.069 0 8724 2006 0.094 0.090 0.087 0.084 0.074 4 8618 2007 0.083 0.080 0.079 0.077 0.076 0 8667 2008 b 0.082 0.081 0.081 0.079 0.080 7 8752 Footnotes: b - The 8-hour ozone standard was revised effective May 27 , 2008. The previous eight-hour average of 0.080 ppm was lowered to 0.075 ppm.

### 86 CASA GRANDE OZONE DATA (in ppm) 1 HOUR AVERAGES Table C-7

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading Number of Daily Exceedances Expected Exceedance Rate Number of Sample Hours

1993 0.092 0.090 0.084 0.082 0 0 8720 1994 0.091 0.091 0.090 0.088 0 0 7894 1995 0.083 0.083 0.081 0.080 0 0 8638 1996 0.104 0.091 0.085 0.084 0 0 8708 1997 0.082 0.082 0.080 0.079 0 0 8653 1998 0.093 0.079 0.076 0.075 0 0 8478 1999 0.090 0.087 0.084 0.084 0 0 8436 2000 0.105 0.094 0.090 0.089 0 0 8262 2001 0.084 0.084 0.083 0.083 0 0 8561 2002 0.088 0.088 0.083 0.083 0 0 8687 2003 0.090 0.089 0.086 0.083 0 0 8203 2004 0.077 0.077 0.076 0.074 0 0 8643 2005 0.089 0.088 0.081 0.080 0 0 8580 2006 a 0.083 0.083 0.082 0.080 N/A N/A 8364 2007 a 0.079 0.078 0.075 0.074 N/A N/A 8623 2008 a 0.082 0.080 0.080 0.079 N/A N/A 8681 Footnotes: a - The 1-hour ozone standard was revoked in August 2005. One-hour averages are listed here for trend analysis.



### CASA GRANDE OZONE DATA (in ppm) 8 HOUR AVERAGES Table C-8

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading 3 Year Avg of the 4th Highest Number of Daily Excursions Number of Sample

Hours 1993 0.081 0.074 0.073 0.072 N/A 0 8718 1994 0.079 0.077 0.076 0.076 N/A 0 7885 1995 0.077 0.074 0.073 0.071 0.073 0 8632 1996 0.086 0.081 0.080 0.079 0.075 1 8703 1997 0.075 0.074 0.073 0.072 0.074 0 8704 1998 0.070 0.069 0.069 0.068 0.073 0 8480 1999 0.083 0.083 0.079 0.078 0.072 0 8424 2000 0.087 0.086 0.086 0.085 0.077 5 8257 2001 0.078 0.078 0.074 0.074 0.079 0 8599 2002 0.080 0.079 0.079 0.077 0.078 0 8715 2003 0.077 0.074 0.073 0.073 0.074 0 8227 2004 0.072 0.070 0.070 0.070 0.073 0 8667 2005 0.081 0.075 0.073 0.072 0.071 0 8594 2006 0.076 0.077 0.074 0.073 0.071 0 8369 2007 0.071 0.071 0.071 0.070 0.071 0 8616 2008 b 0.077 0.077 0.074 0.073 0.072 2 8698 Footnotes: b - The 8-hour ozone standard was revised effective May 27, 2008 . The previous eight-hour average of 0.080 ppm was lowered to 0.075 ppm.

### 87 COMBS OZONE DATA (in ppm) 1 HOUR AVERAGES Table C-9

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading Number of Daily Exceedances Expected Exceedance Rate Number of Sample Hours

2002 0.085 0.080 0.080 0.078 0 0 2709 (seasonal) 2003 0.101 0.096 0.090 0.086 0 0 5059 (seasonal) 2004 0.080 0.069 0.068 0.067 0 0 4868 (seasonal) 2005 0.093 0.091 0.088 0.087 0 0 5123 (seasonal) 2006 a 0.095 0.091 0.089 0.086 N/A N/A 5102 (seasonal) 2007 a 0.075 0.072 0.071 0.070 N/A N/A 5100 (seasonal) 2008 a 0.093 0.092 0.086 0.085 N/A N/A 5117 (seasonal) Footnotes: a - The 1-hour ozone standard was revoked in August 2005. One-hour averages are listed here for trend analysis.



### COMBS OZONE DATA (in ppm) 8 HOUR AVERAGES Table C-10

Year Maximum Reading 2 nd Highest Reading 3 rd Highest Reading 4 th Highest Reading 3 Year Avg of the 4th Highest Number of Daily Excursions Number of Sample Hours

2002 0.075 0.074 0.071 0.068 N/A 0 2712 (seasonal) 2003 0.081 0.073 0.073 0.072 N/A 0 5091 (seasonal) 2004 0.064 0.062 0.060 0.059 0.066 0 4880 (seasonal) 2005 0.080 0.077 0.069 0.067 0.066 0 5141 (seasonal) 2006 0.079 0.073 0.072 0.071 0.066 0 5510 (seasonal) 2007 0.063 0.062 0.061 0.057 0.065 0 5113 (seasonal) 2008 b 0.074 0.072 0.071 0.071 0.066 0 5133 (seasonal) Footnotes: b - The 8-hour ozone standard was revised effective May 27 , 2008. The previous eight-hour average of 0.080 ppm was lowered to 0.075 ppm.



### CITY OF MARICOPA OZONE DATA (in ppm) 1 HOUR AVERAGES Table C-11

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading Number of Daily Exceedances Expected Exceedance Rate Number of Sample Hours

2002 0.089 0.086 0.077 0.075 0 0 2805 (seasonal) 2003 0.093 0.092 0.085 0.085 0 0 5103 (seasonal) 2004 0.078 0.072 0.072 0.071 0 0 5112 (seasonal) 2005 0.079 0.078 0.075 0.069 0 0 5080 (seasonal) 2006 a 0.087 0.080 0.0074 0.074 N/A N/A 4893 (seasonal) 2007 a 0.067 0.065 0.064 0.063 N/A N/A 5053 (seasonal) 2008 a 0.085 0.078 0.076 0.075 N/A N/A 5098 (seasonal) Footnotes: a - The 1-hour ozone standard was revoked in August 2005. One-hour averages are listed here for trend analysis.

### 88 CITY OF MARICOPA OZONE DATA (in ppm) 8 HOUR AVERAGES Table C-12

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading 3 Year Avg of the 4th Highest Number of Daily Excursions Number of Sample Hours

2002 0.083 0.080 0.073 0.068 N/A 0 2811 (seasonal) 2003 0.082 0.077 0.075 0.075 N/A 0 5110 (seasonal) 2004 0.072 0.067 0.065 0.064 0.069 0 5136 (seasonal) 2005 0.070 0.069 0.067 0.062 0.067 0 5082 (seasonal) 2006 0.082 0.077 0.068 0.068 0.065 0 4889 (seasonal) 2007 0.061 0.060 0.059 0.059 0.063 0 5068 (seasonal) 2008 b 0.073 0.070 0.070 0.069 0.065 0 5108 (seasonal) Footnotes: b - The 8-hour ozone standard was revised effective May 27 , 2008. The previous eight-hour average of 0.080 ppm was lowered to 0.075 ppm.



### PINAL AIR PARK OZONE DATA (in ppm) 1 HOUR AVERAGES Table C-13

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading Number of Daily Exceedances Expected Exceedance Rate Number of Sample Hours

2002 0.087 0.085 0.079 0.078 0 0 2789 (seasonal) 2003 0.083 0.080 0.080 0.079 0 0 5080 (seasonal) 2004 0.074 0.073 0.072 0.072 0 0 5103 (seasonal) 2005 0.088 0.085 0.084 0.084 0 0 4984 (seasonal) 2006 a 0.083 0.079 0.077 0.076 N/A N/A 5084 (seasonal) 2007 a 0.078 0.073 0.070 0.070 N/A N/A 5108 (seasonal) 2008 a 0.077 0.077 0.075 0.074 N/A N/A 5080 (seasonal) Footnotes: a - The 1-hour ozone standard was revoked in August 2005. One-hour averages are listed here for trend analysis.



### PINAL AIR PARK OZONE DATA (in ppm) 8 HOUR AVERAGES Table C-14

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading 3 Year Avg of the 4th Highest Number of Daily Excursions Number of Sample Hours

2002 0.080 0.074 0.072 0.070 N/A 0 2823 (seasonal) 2003 0.076 0.075 0.075 0.074 N/A 0 5087 (seasonal) 2004 0.069 0.069 0.068 0.067 0.070 0 5120 (seasonal) 2005 0.079 0.079 0.078 0.077 0.072 0 5001 (seasonal) 2006 0.075 0.072 0.071 0.070 0.071 0 5091 (seasonal) 2007 0.072 0.071 0.068 0.066 0.071 0 5120 (seasonal) 2008 b 0.071 0.071 0.071 0.070 0.068 0 5091 (seasonal)

b - The 8-hour ozone standard was revised effective May 27 , 2008. The previous eight-hour average of 0.080 ppm was lowered to 0.075 ppm.

### 89 QUEEN VALLEY OZONE DATA (in ppm) 1 HOUR AVERAGES Table C-15

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading Number of Daily Exceedances Expected Exceedance Rate Number of Sample Hours

2001 0.103 0.103 0.098 0.093 0 0 3651 (seasonal) 2002 0.112 0.110 0.106 0.099 0 0 5225 (seasonal) 2003 0.110 0.110 0.107 0.107 0 0 5357 (seasonal) 2004 0.093 0.092 0.092 0.087 0 0 5081 (seasonal) 2005 0.117 0.113 0.110 0.105 0 0 5125 (seasonal) 2006 a 0.110 0.109 0.103 0.102 N/A N/A 5360 (seasonal) 2007 a 0.089 0.088 0.088 0.087 N/A N/A 5112 (seasonal) 2008 a 0.099 0.095 0.093 0.091 N/A N/A 5084 (seasonal) Footnotes: a - The 1-hour ozone standard was revoked in August 2005. One-hour averages are listed here for trend analysis.



### QUEEN VALLEY OZONE DATA (IN ppm) 8 HOUR AVERAGES Table C-16

Year Maximum Reading 2nd Highest Reading 3 rd Highest Reading 4 th Highest Reading 3 Year Avg of the 4th Highest Number of Daily Excursions Number of Sample Hours

2001 0.084 0.084 0.080 0.079 N/A 0 3651 (seasonal) 2002 0.085 0.083 0.083 0.083 N/A 1 5196 (seasonal) 2003 0.094 0.091 0.090 0.087 0.083 4 5365 (seasonal) 2004 0.077 0.076 0.074 0.073 0.081 0 5095 (seasonal) 2005 0.097 0.096 0.086 0.084 0.081 3 5142 (seasonal) 2006 0.091 0.087 0.080 0.080 0.079 2 5379 (seasonal) 2007 0.077 0.077 0.076 0.076 0.080 0 5133 (seasonal) 2008 b 0.085 0.082 0.082 0.080 0.078 9 5094 (seasonal) b - The 8-hour ozone standard was revised effective May 27 , 2008. The previous eight-hour average of 0.080 ppm was lowered to 0.075 ppm.

### 90 24 HOUR PM 10 

### AVERAGES (IN μ g/m 3 

### )

Table C-17

Year Reading Maximum Number of Daily Exceedances Expected Exceedance Rate 3 Year Average of the Expected Exceedance Rate Apache Junction North (HiVol) 1995 67.72 0 0 N/A 1996 34.05 0 0 N/A 1997 81.0 0 0 0 1998 61.45 0 0 0 1999 64.0 0 0 0 2000 111.4 0 0 0 2001 49.1 0 0 0 2002 b 61.5 0 0 0 2003 j 94.5 0 0 0 Apache Junction South (HiVol) 1995 67.91 0 0 N/A 1996 36.93 0 0 N/A 1997 81.33 0 0 0 1998 62.73 0 0 0 1999 63.5 0 0 0 2000 107.3 0 0 0 2001 93.5 0 0 0 2002 b 62.4 0 0 0 2003 b,g 91.3 0 0 0 Apache Junction Fire Station (HiVol) 2003 b,h 103.3 0 0 N/A 2004 35.7 0 0 N/A 2005 47.0 0 0 0 2006 73.0 0 0 0 2007 48.0 0 0 0 2008 57.0 0 0 0 Casa Grande (HiVol) 1995 77.39 0 0 N/A 1996 73.48 0 0 N/A 1997 a 76.4 0 0 0 1998 b 75.52 0 0 0 1999 64.3 0 0 0 2000 82.5 0 0 0 2001 104.2 0 0 0 2002 b 68.5 0 0 0 2003 98.7 0 0 0 2004 52.8 0 0 0 2005 79.2 0 0 0 2006 81.2 0 0 0 2007 112.4 0 0 0 2008 74.0 0 0 0 Casa Grande (TEOM) 2007 983.4 7 7 N/A 2008 203.0 3 3 N/A Combs (TEOM) 2007 969.5 31 44.6 N/A 2008 270.0 4 4 N/A Coolidge (HiVol) 1995 94.54 0 0 N/A

### 91 Year Reading Maximum Number of Daily Exceedances Expected Exceedance Rate 3 Year Average of the Expected Exceedance Rate 1996 98.07 0 0 N/A 1997 a 102.32 0 0 0 1998 143.79 0 0 0 1999 83.6 0 0 0 2000 76.5 0 0 0 2001 73.4 0 0 0 2002 b 106.4 0 0 0 2003 105.7 0 0 0 2004 57.5 0 0 0 2005 81.4 0 0 0 2006 105.5 0 0 0 2007 82.0 0 0 0 2008 91.0 0 0 0 Cowtown (47mm) 2005 b,k 787.9 8 N/A Avg. > 1.0 2006 606.0 39 278 Avg. > 1.0 2007 759.0 24 167 Avg. > 1.0 2008 465.0 24 146 197 Cowtown (TEOM) 2002 a,b 1390.6 209 209 Avg. > 1.0 2003 718.5 150 150 Avg. > 1.0 2004 b 600.1 105 105 155 2005 b 769.6 163 163 139 2006 1078.9 228 238 169 2007 1014.0 189 190 197 2008 609.0 173 175 201 Eloy (HiVol) 1995 130.23 0 0 N/A 1996 80.83 0 0 N/A 1997 a 81.84 0 0 0 1998 b 110.48 0 0 0 1999 141.6 0 0 0 2000 102.1 0 0 0 2001 142.2 0 0 0 2002 b 146.3 0 0 0 2003 153.9 0 0 0 2004 46.8 0 0 0 2005 72.9 0 0 0 2006 98.7 0 0 0 2007 o 135.5 0 0 0 2008 109.0 0 0 0 Mammoth (HiVol) 1995 81.3 0 0 N/A 1996 32.8 0 0 N/A 1997 46.4 0 0 0 1998 49.2 0 0 0 1999 b 50.0 0 0 0 2000 63.5 0 0 0 2001 99.2 0 0 0 2002 b 52.5 0 0 0 2003 89.4 0 0 0 2004 30.8 0 0 0 2005 32.5 0 0 0 2006 30.7 0 0 0 2007 39.8 0 0 0

### 92 Year Reading Maximum Number of Daily Exceedances Expected Exceedance Rate 3 Year Average of the Expected Exceedance Rate 2008 35.0 0 0 0 City of Maricopa (TEOM) 2005 l 239.1 18 18 Avg. > 1.0 2006 429.0 21 21 Avg. > 1.0 2007 724.0 20 20 21 2008 520.0 6 6 16 Pinal Air Park (HiVol) 1995 65.29 0 0 N/A 1996 48.31 0 0 N/A 1997 64.99 0 0 0 1998 b 67.21 0 0 0 1999 60.4 0 0 0 2000 74.2 0 0 0 2001 b 103.3 0 0 0 2002 b 62.0 0 0 0 2003 107.8 0 0 0 2004 38.8 0 0 0 2005 122.4 0 0 0 2006 76.8 0 0 0 2007 113.0 0 0 0 2008 55.0 0 0 0 Pinal County Housing West (HiVol) 2002 b,f 166.1 1 N/A Avg. > 1.0 2003 288.6 2 11.5 Avg. > 1.0 2004 155.1 1 5.8 Avg. > 1.0 2005 b 157.7 1 6.1 7.8 2006 152.5 0 0 4.0 2007 224.0 1 6.5 4.2 2008 141.0 0 0 3.3 Pinal County Housing East (HiVol) 2004 113.6 0 0 0 2005 179.4 2 11.9 Avg. > 1.0 2006 209.7 3 20.2 10.7 2007 341.0 1 6.1 12.7 2008 245.0 1 5.7 10.7 Pinal County Housing (TEOM) 2002 b,f 394.5 9 9 Avg. > 1.0 2003 357.8 11 11 Avg. > 1.0 2004 490.7 7 7 9 2005 326.0 17 17 11.7 2006 913.0 33 33.6 19.2 2007 2253 19 20 23.5 2008 285.0 10 10 21.2 Riverside (HiVol) 2003 b,i 100.7 0 0 N/A 2004 34.4 0 0 N/A 2005 35.2 0 0 0 2006 82.7 0 0 0 2007 65.0 0 0 0 2008 52.0 0 0 0 Stanfield (HiVol) 1995 85.57 0 0 N/A 1996 100.33 0 0 N/A 1997 a 135.34 0 0 0 1998 112.56 0 0 0

### 93 Year Reading Maximum Number of Daily Exceedances Expected Exceedance Rate 3 Year Average of the Expected Exceedance Rate 1999 106.6 0 0 0 2000 148.7 0 0 0 2001 134.2 0 0 0 2002 b 351.5 2 13.0 4.0 2003 b 170.5 1 6.1 6.1 2004 80.9 0 0 6.1 2005 172.5 1 5.8 4.0 Stanfield (47mm) 2006 m 182.0 2 13.1 Avg. > 1.0 2007 374.0 6 39.6 Avg. > 1.0 2008 201.0 2 11.8 21.5 Stanfield (TEOM)

2006 b,n 727.4 25 26.5 Avg. > 1.0 2007 1062.0 25 25.2 Avg. > 1.0 2008 375.0 14 14 21.9

Footnotes: a - At least one data point during this year was flagged due to an exceptional event and excluded from calculation. b - At least one quarter during this year had less than 75% data recovery c - The Edwards site was located on private property and discontinued on 7/16/1998 at the land owners request. d - The Miller site was located on priv ate property and discontinued on 11/27/1999 following the paving of the dirt road being monitored. e - The Eleven Mile Corner site was closed on 7/22/2002 due to improper siting conditions. f - Monitoring began at the Pinal County Housing site on 8/1/ 2002. The Pinal County Housing site replaced the Eleven Mile Corner site. g - The Apache Junction South monitor was discontinued on 7/1/2003, and relocated to Apache Junction Fire Station. h - Monitoring began at the Apache Junction Fire Station site on 7/2/2003. i - Monitoring began at the Riverside site on 3/10/2003. j - The Apache Junction North monitor was di scontinued on 1/1/2004, and relocated to Pinal County Housing. k - 47mm filter based monitoring began at the Cowtown s ite on 8/14/05, and data reporting began as of 10/1/05. l - Monitoring began at the (City of) Maricopa site on 12/4/04, and data reporting began as of 1/1/05. m - The Wedding HiVol sample r was replaced on 4/12/06 with an Andersen RAAS10- 100 sampler at the Stanfield site. n - Beginning in February of 2006 a R&P TEOM 1400a sampler was installed at the Stanfield site. o – On 3/2/07 the Andersen HiVol was relocated from a Ci ty of Eloy building to a Pinal County building approximately 650 feet to the north-northeast.94ANNUAL PM10AVERAGES (INμg/m3)Table C-1819981999200020012002200320042005200620072008Apache Junction North (HiVol) 24.625.827.422.7 21.3b20.3hApache Junction South (HiVol) 25.6 27.5 28.4 23.4 21.5b20.4b,eApache Junction Fire Station (HiVol) 26.7b,f18.4 19.9 23.6 18.1 19.6Casa Grande (HiVol)30.6b35.3 34.7 29.2 30.4b31.5 24.4 30.8 35.9 35.3 29.9Casa Grande (TEOM) 55.2b45.0Combs School (TEOM) 89.9b56.4Coolidge (HiVol)37.2 39.6 37.4 32.0 32.8b35.3 24.5 36.0 44.0 35.5 33.5Cowtown (47mm)294.4b,i220.1 167.5 145.3Cowtown (TEOM)261.7a,b170.1 132.2b200.4b230.4 181.3 160.5Eloy (HiVol)43.7b45.9 41.7 35.1 46.5b41.5 27.8 33.5 38.3 42.3m36.3Mammoth (HiVol)21.8 22.5b22.0 22.6 18.8b16.4 11.8 13.5 14.8 12.7 14.6City of Maricopa (TEOM)70.1j78.6 73.7 58.6Pinal Air Park(HiVol)27.1b30.3 30.9 26.7b30.2b28.6 20.3 22.4 29.5 29.5 25.8Pinal County Housing West ( HiVol)56.6b,d61.0 47.1 56.7b64.3 56.0 43.1Pinal County Housing East ( HiVol) 45.1 58.5 62.8 62.3 47.5Pinal County Housing (TEOM) 75.9b,d66.6 55.9 68.7 87.1 83.7 63.3Riverside (HiVol)23.9b,g15.2 18.1 23.3 23.6 20.9Stanfield (HiVol)41.3 56.6 45.7 41.9 59.7b46.1b33.9 52.1Stanfield (47mm)81.4k90.9 61.0Stanfield (TEOM)82.6b,l84.3 67.8Footnotes:a - At least one datapoint during this year was flagged due to anexceptional event and excluded from calculation.b - At least one quarter during this year had less than 75% data recovery.d - Monitoring began at the Pinal County Housing site on 8/1/2002. The Pinal County Housing site replaced the Eleven Mile Corner site.e - The Apache Junction South monitor was discontinued on 7/1/2003, and relocated to Apache Junction Fire Station.f - Monitoring began at the Apache Junction Fire Station site on 7/2/2003.g - Monitoring began at the Riverside site on 3/10/2003.h - The Apache Junction North monitor was discontinuedon 1/1/2004, and relocatedto Pinal County Housing.i - Filter-based sampling began at the Cowtown siteon 8/14/05, and data reporting began 10/1/05.j - Monitoring began at the (City of) Maricopasite on 12/4/04, and data reporting began 1/1/05.k - The Wedding HiVol sampler was replaced on 4/12/06 withan Andersen RAAS10-100 sampler at the Stanfield site.l - In February of 2006 a R&P TEOM 1400asampler was installed at Stanfield.m - On 3/2/07 the Andersen HiVol was relocated from a City ofEloy building to a Pinal County building approximately 650 feet to thenorth-northeast. The annual average is from the three quarters at the new location.

### 95 24 HOUR PM 2.5 

### AVERAGES (in μ g/m 3 

### ) Table C-19

Year Maximum Reading 98 th Percentile 3 year average of the 98 th percentile Apache Junction 1999 18.7 15.5 N/A 2000 44.5 18.0 N/A 2001 14.0 13.1 16 2002 23.5 13.1 15 2003 a 38.0 21.1 16 2004 17.0 10.3 15 2005 12.7 10.6 14 2006 10.7 9.3 10 2007 15.9 14.6 12 2008 23.3 15.4 13 Casa Grande 1999 19.5 18.1 N/A 2000 22.2 18.9 N/A 2001 18.1 16.7 18 2002 23.5 20.8 19 2003 32.2 26.7 21 2004 16.6 13.7 20 2005 19.3 16.9 19 2006 16.1 15.4 15 2007 26.6 22.4 18 2008 23.5 22.0 20 Cowtown 2005 a,b 144.8 78.9 N/A 2006 69.4 48.9 N/A 2007 59.7 53.9 61 2008 41.7 40.7 48 Footnotes: a – At least one quarter during this year had less than 75% data recovery b - 47mm filter based monitoring began at the Cowtown site on 8/14/05, and data reporting began as of 10/1/05.

### 96 ANNUAL PM 2.5 

### AVERAGES (IN μ g/m 3 

### ) Table C-20

Year Annual Average 3 year average of the annual means Apache Junction 1999 7.41 N/A 2000 7.28 N/A 2001 6.26 7.0 2002 6.39 6.6 2003 a 6.30 6.3 2004 a 5.51 6.1 2005 5.51 5.8 2006 5.31 5.4 2007 6.96 5.9 2008 7.52 6.6 Casa Grande 1999 9.53 N/A 2000 8.48 N/A 2001 7.73 8.5 2002 8.46 8.2 2003 8.42 8.2 2004 7.13 8.0 2005 7.33 7.6 2006 7.55 7.3 2007 10.25 8.4 2008 10.61 9.5 Cowtown 2005 a,b 33.1 N/A 2006 22.7 N/A 2007 22.5 26 2008 19.6 21.6 Footnotes:

a - At least one quarter during this y ear had less than 75% data recovery
b - 47mm filter based monitoring began at the Cowtown site on 8/14/05, and data reporting began as of 10/1/05.

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# Appendix D

Public Comments

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# Appendix D

This appendix summarizes the public comment period and hearing conducted in relation to this document.

D.1 Public Comment Period

Pinal County Air Quality will pos t the draf t 2008 Ambient Monitoring Network Review and Data Summary on the department’s websit e for the period of May 1, 2009 to June 1, 2009.

D.2 Public Hearing

Pinal County Air Quality will condu ct a public hearing concerning the draft 2008 Ambient Monitoring Network Review and Da ta Summary on June 1, 2009. The sign in sheet from this meeting will be included in this appendix.

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