# 2015 West Pinal Moderate
**PM10 Nonattainment Area SIP** 

Air Quality Division December 21, 2015 Final

## This page is intentionally blank.

## Table of Contents

1 EXECUTIVE SUMMARY

................................ ................................ ................................ ........ 9

2 COMPLETENESS CRITERIA (40 C.F.R. Part 51, Appendix V)

................................ .............. 13

2.1 Administrative Materials

................................ ................................ ...................... 13

2.1.1 A formal letter of submittal from the Governor or hi s [her] designee, requesting EPA approval of the plan or revision thereof (hereafter ‘‘the plan’’).

................................ ................................ ................................ .... 13

2.1.2 Evidence that the St ate has adopted the plan in the State code or body of regulations; or issued the permit, order, consent agreement (hereafter ‘‘document’’) in final form.

................................ .................. 13

2.1.3 Evidence that the State has the necessary legal authority under State law to adopt and implement the plan.

................................ .................. 13

2.1.4 A copy of the actual regulation, or document submitted for approval and incorporation by reference into the plan, including indication of the changes made to the existing approved plan, wh ere applicable.

......... 14

2.1.5 Evidence that the State followed all of the procedural requirements of
the State’s laws and constitution in conducting and completing the adoption/issuance of the plan.

................................ .............................. 16

2.1.6 Evidence that public notice was given of the proposed change consistent with procedures approved by EPA, including the date of publication of such notice.

................................ ................................ ..... 17

2.1.7 Certification that public hearing(s) were held in accordance with the information provided in the public notice and the State’s laws and constitution, if applicable and consistent with the public hearing requirements in 40 CFR 51.102.

................................ ............................ 17

2.1.8 Compilation of public comments and the State’s response thereto.

.... 17

2.2 Technical Support

................................ ................................ ................................ . 17

2.2.1 Identification of all regulated pollutants affected by the plan.

............. 17

2.2.2 Identification of the locations of affected sources including the EPA attainment/ nonattainm ent designation of the locations and the status of the attainment plan for the affected areas(s).

................................ .. 17

2.2.3 Quantification of the changes in plan allowable emissions from the affected sources; estimates of changes in current actual emissions from affected sources or, where appropriate, quantification of changes in actual emissions from affected sources throughcalculations of the

December 21, 2015 Final 1diff erences between certain baseline levels and allowable emissions anticipated as a result of the revision.

................................ .................. 18

2.2.4 The State’s de monstration that the national ambient air quality standards, prevention of significant deterioration increments, reasonable further progress demonstration, and visibility, as applicable, are protected if the plan is approved and implemented (Section 110(l) demonstration).

................................ ................................ ..................... 18

2.2.5 Modeling information required to support the proposed revision, including input data, output data, mod els used, justification of model selections, ambient monitoring data used, meteorological data used, justification for use of offsite data (where used), modes of models used, assumptions, and other information relevant to the determination of adequacy of t he modeling analysis.

................................ ....................... 18

2.2.6 Evidence, where necessary, that emission limitations are based on
continuous emission reduction te chnology.

................................ .......... 18

2.2.7 Evidence that the plan contains emission limitations, work practice standards and recordkeeping/reporting requirements, where necessary, to ensure emission levels.

................................ .................... 19

2.2.8 Compliance/enforcement strategies, including how compliance will be determined in practice.

................................ ................................ .......... 19

2.2.9 Special economic and technological justifications required by any applicable EPA policies, or an explanation of why such justifications are not necessary.

................................ ................................ ........................ 19

3 INTRODUCTION

................................ ................................ ................................ ................. 21

3.1 Statement of Introduction and Purpose

................................ ............................... 21

3.2 National Ambient Air Quality Standards

................................ ............................... 21

3.3 U.S. EPA's Particulate Matter NAAQS

................................ ................................ ... 22

3.4 Regulatory Background

................................ ................................ ......................... 23

3.5 West Pinal County PM 10 Nonattainment Area Description

................................ .. 24

3.5.1 West Pinal County PM 10 Nonattainment Area Boundary

...................... 24

3.5.2 Geography and Climate

................................ ................................ ......... 26

3.5.3 Population

................................ ................................ .............................. 27

3.5.4 County Economy

................................ ................................ .................... 28

3.6 General SIP Approach

- Regulatory Requirements and Guidance

........................ 30

3.6.1 Clean Air Act Requirements for Nonattainment Area Plans

................. 30

3.6.2 EPA Guidance

................................ ................................ ......................... 39

4 AMBIENT AIR QUALITY MONITORING

................................ ................................ .............. 41

December 21, 2015 Final 24.1 Monitoring Site, Equipment, and Quality Assurance Procedures

........................ 41

4.2 Historical PM 10 Data Summary

................................ ................................ .............. 45

4.3 24

- Hours PM 10 NAAQS Compliance

- 2012

- 2014

................................ ................. 46

5 ANNUAL EMISSIONS INVENTORY

................................ ................................ ..................... 48

5.1 Meteorological Scenarios and General Methodology

................................ .......... 48

5.2 Windblown Methodologies for the Base Years 2008 and 2018

........................... 49

5.2.1 Annual Windblown Methodologies

................................ ....................... 49

5.2.2 Adjusting and Projecting the 2008 Base Year Emissions to 2018

.......... 53

5.3 Activity

- Based Emissions for the Base Years 2008 and 2018

............................... 54

5.3.1 Agriculture Crop Emissions

................................ ................................ .... 54

5.3.2 Concentrated Animal Feeding Operations (CAFO) Emissions

............... 55

5.3.3 Dairy Emissions

................................ ................................ ...................... 56

5.3.4 Fugitive Dust and Exhaust Emissions from Paved Roads

....................... 56

5.3.5 Fugitive Dust and Exhaust Emissions from Unpaved Roads

.................. 57

5.3.6 Nonroad Emissions

................................ ................................ ................ 58

5.3.7 Railroad Emissions

................................ ................................ ................. 58

5.3.8 Construction Emissions

................................ ................................ .......... 59

5.3.9 Emissions from Permitted Stationary Sources

................................ ...... 59

5.3.10 Fuel Combustion Sources

................................ ................................ ...... 59

5.3.11 Unpaved Parking

................................ ................................ .................... 60

5.4 Comparison of Base Year Inventories to Control Inventories

.............................. 60

5.5 Motor Vehicle Emissions Budget (MVEB) Summary

................................ ............. 61

6 CONTROL MEASURES

................................ ................................ ................................ ........ 64

6.1 Agricultural Rule

– Attainment and Contingency in Part

................................ ...... 64

6.1.1 Commercial Farms Summary (R18

- 2

- 610 and

- 610.03)

........................ 64

6.1.2 Appendix 2

– Test Method for S ilt Loading

................................ ........... 65

6.1.3 Commercial Animal Operations Summary (R18

- 2

- 611 and

- 611.03)

.... 65

6.1.4 Irrigation Districts in the Pinal County PM Nonattainment Area (R18

- 2

- 612 and

- 612.01)

................................ ................................ .................... 66

6.1.5 Implementation Schedule

– Agricultural Rules

................................ ..... 66

6.1 .6 Enforceability

................................ ................................ ......................... 66

6.1.7 Credited Annual Emission Reductions from Agricultural BMP Rules

.... 76

6.2 Fugitive dust

– Contingency Measure

................................ ................................ .. 77

December 21, 2015 Final 36.2.1 Fugitive Dust Rule Summary

................................ ................................ .. 77

6.2.2 Planned Rule Implementation Schedule

– General Fugitive Dust Rule

. 77

6.2.3 Enforceability

................................ ................................ ......................... 77

6.2.4 Credited Annual Emissions Reductions from Fugitive Dust Rule

.......... 81

6.3 Construction Rule

- Contingency

................................ ................................ .......... 82

6.3.1 Construction Rule Summary

................................ ................................ .. 82

6.3.2 Planned Rule I mplementation

................................ ............................... 82

6.3.3 Enforceability

................................ ................................ ......................... 82

6.3.4 Credited Annual Emissions Reductions

................................ ................. 84

6.4 Statutory Amendments

................................ ................................ ......................... 85

6.4.1 Agricultural Best Ma nagement Practices

- Arizona Revised Statutes (A.R.S.) § 49

- 457

................................ ................................ ..................... 85

6.4.2 High Risk Forecast

- Arizona Revised Statutes (A.R.S.) § 49

- 424(11)

..... 86

6.5 Adequate Resources

................................ ................................ ............................. 86

6.5.1 Adequate Resources

– Agricultural Rules

................................ .............. 8 6

6.5.2 Adequate Resources

- Fugitive Dust and Construction Rules

............... 87

7 ATTAINMENT DEMONSTRATION AND REASONABLE FURTHER PROGRESS

..................... 89

7.1 Attainment Demonstration

................................ ................................ ................... 89

7.1.1 Stagnation Attainment Modeling Background

................................ ...... 90

7.1.2 High Wind Attainment Modeling Background

................................ ....... 92

7.1.3 How ADEQ Accounted for Attainment Controls

................................ .... 97

7.1.4 Comparative Concentration Table

................................ ......................... 98

7.1.5 Annual Inventory Attainment Reductions

................................ ............. 99

7.2 Reason able Further Progress

................................ ................................ ................ 99



## List of Figures

Figure 1

- 1 Pinal County at a Glance

................................ ................................ ................................ 9 Figure 3

- 1 Map of West Pinal County PM 10 Nonattainment Area

................................ ............... 25 Figure 3

- 2 Casa Grande National Monument, Arizona, Monthly Average Temperatures and Precipitation: 1981

- 2010 Normals

................................ ................................ ................................ 27 Figure 4

- 1 West Pinal County PM 10 Nonattainment Area

................................ ............................ 42 Figure 4

- 2 Three

- Year Average Expected Rate of Exceedance

................................ ..................... 46 Figure 7

- 1 Re asonable Further Progress from Dec. '15 through Dec. '18

................................ .. 101 Figure 7

- 2: Reasonable Further Progress from Dec. '15 through Dec. '1 8

................................ . 101

December 21, 2015 Final 4

## List of Tables

Table 2

- 1 Rules and Statutes to Be Added to and Removed from the SIP

................................ ... 14 Table 3

- 1 PM 10 NAAQS History

................................ ................................ ................................ ..... 22 Table 3

- 2 Names and Elevations of West Pinal County Cities

................................ ...................... 26 Table 3

- 3 West Pinal County PM 10 Nonattainment Area Population Distribution

– 2008 Emissions Inventory Base Year

................................ ................................ ................................ ..... 28 Table 3

- 4 Pinal County Civilian Employed Population 16 Years and Over

– 2013 U.S. Census
Bureau

................................ ................................ ................................ ................................ ........... 29 Table 3

- 5 Annual New Privately

- Owned Residential Building Permits

................................ ......... 30 Table 3

- 6 Clean Air Act (CAA) Requirements for Moderate PM 10 Nonattainment Area SIPs

...... 31 Table 4

- 1 Active Monitors withi n the West Pinal County PM 10 Nonattainment Area

................. 43 Table 4

- 2 2012 to 2014 Maximum 24

- Hour Average PM 10 Compliance

................................ ...... 47 Table 5

- 1 Land Use Categories for Windblown Emissions

................................ ........................... 50 Table 5

- 2 Activity

- Based Emission Source Categories

................................ ................................ .. 54 Table 5

- 3 Comparing B ase Year 2008 to Base Year 2018 to Post Control 2018 Inventories

....... 60 Table 5

- 4 Annual MVEB by Source Sector

................................ ................................ .................... 62 Table 6

- 1 Commercial Farms Rule Test Methods

................................ ................................ ......... 69 Table 6

- 2 CAFO Rule Test Methods

................................ ................................ .............................. 72 Table 6

- 3 Irrigation Districts Rule Test Methods

................................ ................................ .......... 74 Table 6

- 4 Agricultural Best Management Practices Rule Reductions

................................ .......... 76 Table 6

- 5 General Fugitive Dust Rule Test Methods

................................ ................................ .... 80 Table 6

- 6 Fugitive Dust Rule Attributable Annual Inventory Reductions (TPY)

........................... 81 Table 6

- 7 Construction Rule Test Methods

................................ ................................ .................. 84 Table 6

- 8 Annual Inventory Reductions Attributable to Construct ion Rule (TPY)

....................... 84 Table 7

- 1 Values used for Example Windblown Dust Calculation

................................ ................ 95 Table 7

- 2 Comparative Design Day Concentration between Base 2008, Projected 2018, and Projected Controlled 2018

................................ ................................ ................................ ............ 98 Table 7

- 3 Annual Inventory Reductions from the Attainment Targeting Sections of the Ag BMP Rules (TPY)

................................ ................................ ................................ ................................ .... 99 Table 7

- 4 Summary of Contingency Measure Reductions

................................ .......................... 102



## List of Appendices

Appendix A: Pinal County PM Inventory Preparation Plan (IPP) Appendix B: Pinal County PM 10 Nonattainment Area Emissions Inventories for 2008 and 2018 Base Years and Design Days (EI TSD)

December 21, 2015 Final 5Appendix C: Pinal County PM 10 Nonattainment Area Source Apportionment Modeling fo r 2008 and 2018 Base Scenario Design Days (Modeling TSD) Appendix D: Pinal County PM 10 Nonattainment Area 2018 Attainment Demonstration and Controlled Emissions Inventories (Attainment TSD) Appendix E: Procedural Requirements and Authority Appendix F: Rea sonably Available Control Measures Analysis (RACM) Appendix G: Rules, Statutes, or Other Documents for Approval

Appendix A: Pinal County PM Inventory Preparation Plan (IPP) Appendix A

- A 2008 24

- Hour Average PM10 Concentrations Recorded at Six
Pinal County TEOM Monitoring Sites Appendix A

- B Plots of Hourly PM10 Concentration, Wind Speed, Wind Direction, and Mixing Height Modeled at Cowtown, Pinal County Housing, and Stanfield Monitoring Sites on October 29, 2008 Appendix A

- C Statistics of the High W ind PM10 Exceedance Days at Cowtown
in 2008 Appendix A

- D Statistics of the High Wind PM10 Exceedance Days at Stanfield in
2008 Appendix A

- E Statistics of the High Wind PM10 Exceedance Days at Pinal County Housing in 2008 Appendix A

- F Statistics of the P M10 Exceedance Days at Maricopa in 2008 Appendix A

- G Statistics of the PM2.5 Exceedance Days at Cowtown in 2008 Appendix A

- H Road Count Data Appendix A

- I Method for the Back

- Calculation of Wind

- Blown Emission Factors
from Field Measured PM10 Concentrati ons, Arizona Department of Environmental Quality Air Quality Division Appendix A

- J MAG 2012 Five Percent Plan for PM10 for the Maricopa County Nonattainment Area, May 2012 Appendix B: Pinal County PM 10 Nonattainment Area Emissions Inventories for 2008 and 2018 Base Years and Design Days (EI TSD)
Exhibit B

- I Analysis of Unpaved Roads in the Pinal County PM10
Nonattainment Area Exhibit B

- II Pinal County Field Sampling and Analysis for the Silt Characterization of Unpaved Road Dust and Agricultural Soil
Exhib it B

- III Pinal County Crops Calendar and High Wind Crop Disturbance Description Exhibit B

- IV Traffic Counts (ADT levels) for the Unpaved Roads in Each of the Modeling Domain
Exhibit B

- V Methodology for Estimating Windblown Emission Factors within 1
MPH Win d Speed Bins
Exhibit B

- VI Evaluation of a Wind Erosion PM10 Emission Equation for Agricultural Lands in the Western Pinal County PM10
Nonattainment Area

December 21, 2015 Final 6Exhibit B

- VII Ambient Monitoring Data Based Emission Factor Adjustment Arizona Department of Environmental Quality (ADEQ) Air Quality
Division Exhibit B

- VIII NONROAD Input Files (2008 and 2018)
Exhibit B

- IX Agricultural Unpaved Road Activity and Speed Notes
Exhibit B

- X Listing of Diurnal Profiles for Windblown, Activity

- Based, and Total
Emissions on High Wind Days
Exhibit B

- XI Pinal County Land Use Descriptions
Exhibit B

- XII Selection of Cowtown PM 10 Stagnation Design Day Exhibit B

- XIII Cowtown Stagnation Design Day Modeling Domain Comparison: October 29, 2008 vs. October 30, 2008
Exhibit B

- XIV Shape Files Used in Inventory Development and Modeling
Exhibit B

- X V Documentation of Control Efficiency for Nissan and Volkswagen
Test Tracks
Exhibit B

- XVI. West Pinal County PM10 Precursor Significance Determination Appendix C: Pinal County PM 10 Nonattain ment Area Source Apportionment Modeling for 2008 and 2018 Base Scenario Design Days (Modeling TSD)
Exhibit C

- I High Wind Design Day Example Calculation Appendix D: Pinal County PM 10 Nonattainment Area 2018 Attainment Demonstration and
Controlled Emissions Inventories (Attainment TSD)
Exhibit D

- I Agricultural Supplemental Information
Exhibit D

- II MAG Methodology for MOVES2014 Appendix E: Procedural Requirements and Authority
Exhibit E

- I Delegation of Authority
Exhibit E

- II Authorizing Statutes
Exhibit E

- II I Public Notice and Affidavit of Publication of Notice
Exhibit E

- IV Public Hearing Agenda
Exhibit E

- V Public Hearing Sign

- in Sheet
Exhibit E

- VI Public Hearing Officer Certification
Exhibit E

- V I I Compilation of Comments and State Responses
Exhibit E

- VII I Public Hearing Transcript Appendix F: Reasonably Available Control Measures Analysis (RACM)
Exhibit F

- I Available Measures
Exhibit F

- II Construction Comparison Exhibit F

- III Agricultural Comparison
Exhibit F

- IV Fugitive Dust Comparison Exhibit F

- V Information on Gallons per Head Standard Providing More Benefits over a Strict Moisture Percentage for Feed Yard Pens Appendix G: Rules, Statutes, or Other Documents for Approval
Exhibit G

- I Certified A.R.S. § 49

- 424 (201 5 ) Duties of department ( revised
hi gh risk forecast mandate included)
Exhibit G

- II House Bill 2125, Amending A.R.S. § 49

- 424 (Fifty

- first Legislature, Second Regular Session, 2014, Chapter 86) ( reflecting changes from most recent approved version )

December 21, 2015 Final 7Exhibit G

- III History of A.R.S. § 49

- 457: H ouse Bill 2394, Fifty

- second Legislature, First Regular Session, 2015, Chapter 243, § 1, amending A.R.S. § 49

- 457; A.R.S. § 49

- 457 (2011); A.R.S. § 49

- 457 (2005) (same as approved version)
Exhibit G

- IV Certified A.R.S. § 49

- 457 Agricultural best managemen t practices committee; members; powers; permits; enforcement; preemption; definitions ( effective January 1, 2016 ) (last amended by House Bill 2394, Fifty

- second Legislature, First Regular Session, 2015, Chapter 243, § 1)
Exhibit G

- V Redline Version of Changes from SIP Approved to Current Version of A.R.S. § 49

- 457 effective January 1, 2016
Exhibit G

- VI Certified Final Rule

- ADEQ Enforced Agricultural Best Management Practices Committee Rules for West Pinal County
PM10 Nonattainment A rea (Ag ricultural BMP Rules )
Exhibit G

- VII Certified F inal Rule

- Pinal County Construction Sites

- Fugitive Dust Rule for West Pinal PM10 Nonattainment Area (Construction Rule)
Exhibit G

- VIII Certified Final Rule

- Pinal County West Pinal PM10 Moderate Nonattainment Area Fugitive Dust Rule (Fugitive Dust Rule) Appendix H : Pinal County Rulemaking Process Documentation

– Construction Rule Appendix I : Pinal County Rulemaking Process Documentation

– General Fugitive Dust Rule

December 21, 2015 Final 8

## 1 **EXECUTIVE SUMMARY**

The West Pinal County PM 10 1 Nonattainment Area is in Central Arizona, located within a basin between the Phoenix and Tucson metropolitan areas. Pinal County as a whole encompasses 5,365.61 2 square miles and has two distinct regions: the eastern portion which is cha racterized by mountains with elevations up to 6, 441 feet and the western region primarily comprised of low desert valleys and irrigated agriculture. Figure 1

- 1 illustrates the geographical location of Pinal County within the State of Arizona.

Source: Pinal County Economic Development. 3

1 Particulate matter with a di ameter of 10 microns or less

2 United States Census Bureau, Pinal County, Arizona QuickFacts Beta, (June 29, 2015) http://quickfacts.census.gov/qfd/states/04/04021.html.

3 Pinal County at Glance, http://www.pinalcountyaz.gov/ed/Pages/Home.aspx (last visited Jun. 29, 2015). Figure 1

- 1 Pinal County at a Glance

December 21, 2015 Final 9Effective July 2, 2012, the U.S. Environmental Protection Agency redesignated a portion of western Pinal County from "unclassifiable” to “nonattainment” area for the 1987 24

- hour PM 10 National Ambient Air Quality Standards (NAAQS). 4 The 24

- hour PM 10 standard was promulgated in 1987 t o be 150 micrograms per cubic meter (μg/m 3 ), meaning that an air quality monitor cannot measure levels of PM 10 greater than 150 micrograms per cubic meter (μ/m 3 ) more than once per year on average over a consecutive three

- year period. 5

The designation of the West Pinal County PM 10 nonattainment area is based on recorded
violations of the PM 10 standard at various monitoring sites within the county. The boundaries of the nonattainment area encompass land that is located within Pinal County north of the east

west line, defined by the southern line of Township 9 South, Gila and Salt River Baseline and Meridian, and west of the north

- south line, defined by the eastern line of Range 8 East, except for Indian Country, certain federal land, and where the boundary e xtends farther east in the
Florence and Picacho Peak areas. 6

This State Implementation Plan for the West Pinal County PM 10 Nonattainment Area consists of the following additional s ix chapters:

Chapter 2

- COMPLETENESS CRITERIA (40 C.F.R. Part 51, Appendix V)

– Notes the Appendix V requireme nts and their respective locations in the rules

Chapter 3

– INTRODUCTION

– Provides an introduction to the physical, demographic, economic description of the area, as well as to the regulatory background of the PM 10 NAAQS in Pinal County.

Chapter 4

– AMBIENT AIR QUALITY MONITORING

– Describes how the Pinal County Ambient Monitoring Network meets the Clean Air Act and U.S. Environmental Protection Agency regulatory requirements.

Chapter 5

– ANNUAL EMISSIONS INVENTORY

– Provides the base year emission inventory fo r the nonattainment area. It summarizes the methodologies used to develop the inventory as required by the Clean Air Act Section 172(c)(3) and to project it from the base year to the attainment year . Additionally, this section summarizes the development a nd quantification of the motor vehicle emissions budget (MVEB).

Chapter 6

– CONTROL MEASURES

– Identifies significant sources of emissions within the West Pinal County Nonattainment Area and presents a summary and analyses of the
control measures chosen to achieve attainment and reasonable further progress

4 Redesignation of West Pinal County as Nonattainment for PM 10 , 77 Fed. Reg. 32024 (May 31, 2012) (codified at
40 C. F.R. pt. 81.303).

5 As calculated rounding to the nearest 10 μg/m 3 , according to 40 C.F.R. § 50, Appendix K (2015) (effective 2006).

6 Redesignation , supra note 4

, at 32029.

December 21, 2015 Final 10(RFP) . The section also summarizes the development and quantification of the
emissions reductions needed to meet contingency measure goals

.

Chapter 7

– ATTAINMENT DEMONSTRATION AND REASONABLE FURTHER PROGRESS

– Presents a summary of the 2008 and 2018 base year modeling for selected design d ays and modeling domains. Summarizes the modeling methodology and results when incorporating additional controls to demonstrate attainment.

December 21, 2015 Final 11

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December 21, 2015 Final 12

## 2 **COMPLETENESS CRITERIA (40 C.F.R. Part 51,**  **Appendix V)**

**2.1 Administrative**  **Materials**

**2.1.1 A formal letter of submittal from the**  **Governor or his**  **[her] designee, requesting EPA approval**  **of the plan or revision thereof (hereafter**  **‘‘the plan’’).**

See the cover letter for this SIP submission and attached delegation of authority from Misael
Cabrera , Director of ADEQ

, to Eric Massey, Director of the ADEQ Air Quality Division, authorizing Mr. Massey to perform any act the ADEQ Director is authorized to perform under the state air quality statutes, including the submission of SIPs to EPA.



### 2.1.2 **Evide nce that the State has adopted the plan in the State code or**  **body of regulations; or issued the permit, order, consent agreement (hereafter ‘‘document’’) in final form.** 

See cover letter to this document wherein the state adopts and submits this SIP revisio n. This is the method of Arizona state adoption. The rules were adopted into Arizona law once finalized and are effective January 1, 2016 . See Appendix G for the certified rules. Additionally, Pinal County’s Board of Supervisors adopted the construction an d fugitive dust rules as law. See Appendix H and Appendix I for more information.



### 2.1.3 **Evidence that the State has the necessary legal authority under**  **State law to adopt and implement the plan.** 

The Arizona Department of Environmental Quality has responsibility for air pollution control and abatement, and as such, is required to adopt and "maintain a state implementation plan that provides for implementation, maintenance and enforcement of national ambient air quality standards and protection of visibility as re quired by the clean air act

. " A.R.S. § 49

- 404(A). ADEQ also maintains authority to issue and administer rules , adopt county rules, and to
submit such rules for approval in the SIP

. Copies of Arizona Revised Statutes sections 49

- 104,
49

- 106, 4 9

- 404, 49

- 406 and 49

- 425, are attached as Appendix E, Exhibit E

- II

.

December 21, 2015 Final 13

### 2.1.4 **A copy of the actual regulation, or document submitted for approval and incorporation by reference into the plan, including**  **indication of the changes made to the existing approved plan, where**  **applicable.**

Appendix G includes the rules and statutes submitted for Approval into the SIP , as well as comparative redlines

. Table 2

- 1 below lists the regulations being added and replaced by this
SIP Revision. In order to promote maximum consistency between state and federal law ADEQ requests that EPA remove each of the rules or statutes identified in the third column of the table from the approved SIP

.

Table 2

- 1 Rules and Statutes to Be Added to and Removed from the SIP

Rule or Statute Added Overarching Arizona Administrative Register or Legislative Citation SIP Rule(s) Replaced (F ederal

R egister Citation)

A.R.S. § 49

- 424 (2015 ) Duties of department (revised high risk forecast mandate included) A.R.S. § 49

- 424 as amended by Laws 2014, Ch. 86, § 1 (House Bill 2125) A.R.S. § 49

- 424 (2011) Duties of department (77 FR 66398, Nov

. 5, 2012)

A.R.S. § 49

- 457 (201 5 ) Agricultural best management practices committee; members; powers; permits; enforcement; preemption;
definitions A.R.S. § 49

- 457 (effective January 1, 2016) as amended by Laws 2015, Ch. 243, § 1 (House Bill 2394) A.R.S. § 49

- 457 (1998 ) Agri cultural best management practices committee; members; powers; permits; enforcement; preemption;
definitions (64 FR 34726, Jun

. 29, 1999)

December 21, 2015 Final 14Rule or Statute Added Overarching Arizona Administrative Register or Legislative Citation SIP Rule(s) Replaced (F ederal

R egister Citation)

A.A.C ., Title 18, Chapter 2, Article 2.

Section s R18

- 2

- 210

. Ambient Air Quality Standards; Area Designations; Classifications

A.A.C. Title 18, Chapter 2, Article 6. Emissions from Existing and New Nonpoint
Sources

Section s R18

- 2

- 610

. Definitions for R18

- 2

- 610.01, R18

- 2

- 610.02, and R18

- 2

- 610.03

... R18

- 2

- 610 .03. Agricultural PM General Permit for Crop Operations; Pinal County PM
Nonattainment Area

R18

- 2

- 611. Definitions for R18

- 2

- 611.01, R18

- 2

- 611.02, and R18

- 2

- 611. 03

... R18

- 2

- 611.03. Agricultural PM General Permit for Animal Operations; Pinal County PM
Nonattain ment Area

R18

- 2

- 612. Definitions for Definitions for R18

- 2

- 612.01

R18

- 2

- 612.01

. Agricultural PM General Permit For Irrigation Districts; PM Nonattainment Areas Designated After June 1, 2009

... Appendix 2

. Test Methods And Protocols

(Other rules were incl uded in this rulemaking, but ADEQ intends to submit them in a subsequent revision) Notice of Final Exempt Rulemaking, 21 A.A.R. 1156, July 24, 2015 ( e ffective July 2, 2015)

. A.A.C. R18

- 2

- 210 (2012) Attainment, Nonattainment, and Unclassifiable Area Designations ( 79 FR 56655

, Sept

. 23, 2014 )

ADEQ is not requesting rule replacement of any of the
A.A.C. Title 18, Chapter 2, Article 6 agricultural rules at this time . ADEQ is only requesting additions , currently

. ADEQ will request any replacements in a subsequent
SIP revision submittal.

December 21, 2015 Final 15Rule or Statute Added Overarching Arizona Administrative Register or Legislative Citation SIP Rule(s) Replaced (F ederal

R egister Citation)

Pinal County Code of Regulations, Chapter 4, Article 3, Construction Sites

– Fugitive Dust

Section s

§ 4

- 3

- 160. General Provisions

– West Pinal
PM10 Nonattainment Area

§ 4

- 3

- 170. Definitions

§ 4

- 3

- 180. Dust Generatin g Operations Standards, Application, Permit and Recordkeeping Requirements

§ 4

- 3

- 190. Violations

( § 1

- 1

- 105. SIP List was also revised in this rulemaking but is not appropriate for
inclusion in the SIP. ADEQ is not requesting approval for this section into the SIP

. ) Notice of Final Rulemaking, 21
A.A.R. 2937

, November 20

, 2015 (effective January 1, 2016). None

Pinal County Air Quality Control District Code of Regulations, Chapter 4, Article 1, West
Pinal P M 10 Moderate Nonattainment Area Fugitive Dust

Section s

§ 4

- 1

- 010. General Applicability § 4

- 1

- 015. Exemptions § 4

- 1

- 020. Definitions § 4

- 1

- 030. Standards § 4

- 1

- 040. Recordkeeping § 4

- 1

- 045. Reporting Requirements § 4

- 1

- 050. Records Retention § 4

- 1

- 060. Violations

( § 1

- 1

- 105. SIP List was also r evised in this rulemaking but i s not appropriate for
inclusion in the SIP

. ADEQ is not requesting approval for this section into the SIP.) Notice of Final Rulemaking, 21
A.A.R. 2925

, November 20

, 2015 (effective January 1, 2016). None



### 2.1.5 **Evidence that the State followed all of the procedural requirements**  **of the State’s laws and constitution in conducting and completing the adoption/issuance of the plan.** 

As demonstrated in Sections 2.1.2

, 2.1.3 and 2.1.7 ADEQ has complied with all requirements of state law for adoption of the rule revisions included in this SIP Revision.

December 21, 2015 Final 16

### 2.1.6 **Evidence that public notice was given of the proposed change consistent with procedures approved by EPA, including the**  **date of publication of such notice.** 

Proof that ADEQ gave notice of the SIP Revision in accordance with A.R.S. § 49

- 444 is attached as Appendix E, Exhibit E

- III

.



### 2.1.7 **Certification that public hearing(s) were held in accordance with the information provided in t**  **he public notice and the State’s laws and constitution, if applicable and consistent with the public**  **hearing requirements in 40 CFR 51.102.**

The certification and other documents related to the public hearing are attached as Appendix E, Exhibit s E

- III throu gh E

- V I I I

.



### 2.1.8 **Compilation of public comments and the State’s response thereto.**

A c ompilation of c omments received and the State ’s r esponses are attached as Appendix E, Exhibit E

- VI I

.



## 2.2 **Technical Support**

**2.2.1 Identification of all regulated pollutants**  **affected by the plan.** 

This plan includes provisions for the regulation of PM 10 emissions. See Section 3.1 , Statement of Introduction and Purpose and Chapter 6, Control Measures

.



### 2.2.2 **Identification of the locations of affected sources including the EPA attainment/ nonattainm**  **ent designation of the locations and the status of the attainment plan for the affected areas(s).** 

This nonattainment plan is applicable to sources within the West Pinal PM 10 Nonattainment
Area. See Section 3.5.1 and Chapter 5, Annual Emissions Inventory

.

December 21, 2015 Final 17

### 2.2.3 **Quantification of the changes in plan allowable emissions from the affected sources; estimates of changes in current actual emissions**  **from affected sources or, where appropriate, quantification of changes in actual emissions from affected sources through** 

**c alculations of the differences between certain baseline levels and**  **allowable emissions anticipated as a result of the revision.**

Calculated e missions reductions due to implementation of control strategies contained in this plan are provided in Section 5.4 C omparison of Base Year Inventories to Control Inventories and Chapter 6, Control Measures

.



### 2.2.4 **The State’s demonstration that the national ambient air quality standards, prevention of significant deterioration increments,**  **reasonable further progress demonstrat ion, and visibility, as**  **applicable, are protected if the plan is approved and implemented (**  **Section 110(l) demonstration ).** 

As i s indicated in S ection 2.1 .4 , this SIP revision will add to or replace existing SIP rules with requirements that are either as str ingent or more stringent. The control strategies contained in this plan are expected to reduce emissions sufficient to demonstrate attainment of the PM 10 NAAQS in the West Pinal PM 10 Nonattainment Area

. None of the changes will interfere with any applicab le requirement concerning attainment, reasonable further progress, increments or visibility.



### 2.2.5 **Modeling information required to support the proposed revision, including input data, output data, models used, justification of**  **model selections, ambient monitor ing data used, meteorological**  **data used, justification for use of offsite data (where used), modes of models used, assumptions, and other information relevant to the**  **determination of adequacy of the modeling analysis.**

EPA approved the use of AERMOD and Rol lback modeling to demonstrate attainment of the

PM 10 NAAQS. Details of the analyses are included in Chapter 7, Attainment Demonstration And Reasonable Further Progress

, Appendix C: Pinal County PM 10 Nonattainment Area Source Apportionment Modeling for 2008 and 2018 Base Scenario Design Days (Modeling TSD) , and Appendix D: Pinal County PM10 Nonattainment Area 2018 Attainment Demonstration and Controlled Emissions Inventories (Attainment TSD)

.



### 2.2.6 **Evidence , where necessary, that emission limitations are based on**  **continuous emission reduction technology.**

Not Applicable.

December 21, 2015 Final 18

### 2.2.7 **Evidence that the plan contains emission limitations, work practice standards and recordkeeping/reporting requirements, where**  **necessary, to ensure emission levels.** 

Information on emissions limits and recordkeeping/reporting requirements is included in Chapter 6, Control Measures and in the agriculture, construction, and general fugitive dust
control rules in Appendix G: Rules, Statutes, or Oth er Documents for Approval

.



### 2.2.8 **Compliance/enforcement strategies, including how compliance will be determined in practice.** 

Compliance and enforcement of the agriculture, construction, and general fugitive dust control strategies included in this plan are discussed in Sections 0

, 6.2.3 , and 6.3.3

.



### 2.2.9 **Special economic and technological justifications required by any applicable EPA policie**  **s, or an explanation of why such justifications are not necessary.** 

This plan does not rely on any special economic and technological justifications in support of the control strategies contained within.

December 21, 2015 Final 19

## (This page is intentionally blank.)

December 21, 2015 Final 20

## 3 **INTRODUCTION**

This chapter describes the purpose of this West Pinal County PM 10 Nonattainment Area SIP
revision , summarizes the regulatory background and requirements for the area, and provides a general overview of the nonattainment area and County.



## 3.1 **Stat ement of Introduction and Purpose** 

Pursuant to Section 107(d)(3) of the Clean Air Act (CAA), the U.S. Environmental Protection Agency (EPA) redesignated an area in western Pinal County from an “unclassifiable” area to a “moderate ” nonattainment area for th e 1987 24

- hour PM 10 National Ambient Air Quality Standards (NAAQS). The EPA based its redesignation on recorded violations of the standard at ambient monitoring sites within the County.

Under the authority granted by the Governor and the State of Arizona , the Arizona Department of Environmental Quality (ADEQ) is responsible for the preparation and submittal of this State Implementation Plan (SIP) revision. 7 The purpose of this SIP revision is to demonstrate how the West Pinal County nonattainment area wil l attain the 1987 24

- hour PM 10 NAAQS.



## 3.2 **National Ambient Air Quality Standards**

Title I of the CAA requires the EPA to set National Ambient Air Quality Standards (NAAQS) for those pollutants that are considered harmful to both the public health and the env ironment. EPA sets standards for six air pollutants: ground

- level ozone, particulate matter, carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead. There are two types of NAAQS: primary and secondary. Primary standards are set to protect human healt h and secondary standards are established to protect public welfare, such as decreased visibility and damage to animals, crops, vegetation, and buildings. 8

The standard for each pollutant is set at a maximum concentration in either parts per million (ppm) by volume, parts per billion (ppb) by volume, or micrograms per cubic meter of air (μ/m 3 ). Each standard also has a distinct averaging time in order to provide the necessary level of protection. 9 These standards are periodically reviewed and are either retained or revised based on review of scientific literature and analyses. 10

7 See Arizona Revised Statutes (Ariz. Rev. Stat.) §49

- 406 (2015).

8 National Ambient Air Quality Standards , http://www.epa.gov/air/criteria.html (last visited Jun. 30, 2015).

9 Id

. 10 See 42 U.S.C. § 7409 (2015).

December 21, 2015 Final 21

## 3.3 **U.S. EPA's Particulate Matter NAAQS**

Particulate matter, or particle pollution, is a complex mixture of small particles and liquid droplets found in the air. Particulate matter (PM) can be directly emitted by a source such as smokestacks, fires, unpaved roads, or construction sites. 11 These particles can also be formed in the atmosphere when gaseous pollutants such as sulfur dioxides and nitrogen dioxides react to form fine partic les. 12

On July 1, 1987, EPA revised the NAAQS for PM, replacing Total Suspended Particulates as the indicator for particulate matter with a new indicator, PM 10 .

. 13 This new indicator included particles with an aerodynamic diameter less than or equal to 10 mi crometers. In order to attain the NAAQS for the 24

- hour PM 10 standard, an air quality monitor cannot measure levels of PM 10 greater than 150 micrograms per cubic meter (μg/m 3 ) more than once per year on average over
a consecutive three

- year period. 14 Table 3

- 1 provides a summary of the PM 10 NAAQS for each of EPA’s review cycles from 1987 through 2012. 15

Table 3

- 1 PM 10 NAAQS History

Date Final Rule Citat ion Primary/ Secondary Averaging
Time Level Form

1987 52 Fed. Reg. 24634 Jul 1, 1987 Primary and Secondary 24

- hour 150 μg/m 3 Not to be exceeded more than

once per year on average over a 3

- year period.

Annual 50 μg/m 3 Annual arithmetic mean averaged over 3 years.

1997 62 Fed. Reg. 38652 Jul 18, 1997 Primary and Secondary 24

- hour 150 μg/m 3 Not to be exceeded more than

once per year on average over a 3

- year period. 16

Annual 17 50 μg/m 3 Annual arithmetic mean averaged over 3 years.

2006 71 Fed. Reg. 61144 Oct 17, 2006 Primary and Secondary 24

- hour 150 μg/m 3 Not to be exceeded more than

once per year on average over a 3

- year period.

2012 78 Fed. Reg. 3086 Primary and 24

- hour 150 μg/m 3 Not to be exceeded more than

11 See 42 U.S.C. § 7602(h) (2015).

12 Particulate Matter , http://www.epa.gov/airquality/particlepollution/ (last visited Jun. 30, 2015).

13 See generally , Revisions to Ambient Air Quality Standards for PM, 52 Fed. Reg. 24634 (J ul. 1, 1987) (codified at 40 C.F.R. pt. 50).

14 As calculated rounding to the nearest 10 μg/m3, according to 40 C.F.R. § 50, Appendix K (2015) (effective 2006). For example, according to the rounding convention dictated by Appendix K, a value of 154 μg/m 3 i s rounded down to 150 μg/m 3

. 15 The historical PM NAAQS also include “total suspended particulates” and PM 2.5 , neither of which is included in this summary.

16 The form of the standard was initially promulgated as 99 th percentile, averaged over 3 years; wh en the 1997 standards were vacated, the form of the 1987 standards remained in place. See National Ambient Air Quality Standards for PM , 69 Fed. Reg. 45592 (Jul. 30, 2004) (codified at 40 C.F.R. pts. 50 and 58).

17 EPA revoked the annual PM 10 NAAQS in 2006

. See National Ambient Air Quality Standards for PM , 71 Fed. Reg. 61144 (Oct. 17, 2006) (codified at 40 C.F.R. pt. 50).

December 21, 2015 Final 22Jan. 15, 2013 Secondary once per year on average over a 3

- year period.



## 3.4 **Regulatory Background**

Most of Pinal County was designated as “unclassifiable” for PM 10 by operation of law upon enactment of the 1990 CAA amendments. On October 14, 2009, EPA notified the Governor of
Arizona and leaders of four Indian Tribes, whose lands are located entirely, or in part, within Pinal County, that air quality monitoring data for the period 2006 to 2008, revealed the area was violating the 24

- hour PM 10 NAAQS. 18 EPA then began the process to redesignate the area
as nonattainment for the 24

- hour PM 10 NAAQS.

Under Section 107(d) of the CAA, governors must submit boundary recommendations for violating areas. ADEQ conducted a “nine factor” analysis based on the an alytical approach established in EPA’s guidance for the 1997 8

- hour ozone, the 1997 PM 2.5 NAAQS, and the 2006

PM 2.5 NAAQS. 19 ADEQ evaluated Pinal County as well as neighboring counties to determine what areas were violating or contributing to violations of the NAAQS. On March 23, 2010, the Governor of Arizona submitted to EPA nonattainment area boundary recommendations, excluding Tribal Lands

. 20

On May 31, 2012, EPA redesignated an area in western Pinal County, Arizona, from
“unclassifiable” to “nonattainment” for the 1987 PM 10 NAAQS. 21 The “West Pinal County PM 10 Nonattainment Area” was classified as a “moderate area” under CAA § 188. The CAA imposes certain planning requirements for moderate nonattainment areas to reduce PM 10 emissions
and atta in the NAAQS. On December 30, 2013, ADEQ submitted a revision to the Arizona SIP to meet certain CAA obligations for PM 10 nonattainment areas (emissions inventory, ambient monitoring data, and base year modeling) and commitments to comply with additional

r equirements. Because the 2013 revision did not contain all required elements for
nonattainment area SIP , ADEQ withdrew the plan from consideration for EPA action on February 19, 2014, in order to develop the remaining elements.

18 Letter from Laura Yoshii, Acting Regional Administrator, EPA Region IX to Governor Brewer of Arizona (Oct. 14, 2009).

19 See Area Desig nations for the Revised 24

- Hour Fine Particle National Ambient Air Quality Standards

, memorandum to Regional Administrators, Regions I

- X, from Robert J. Meyers, Acting Assistant Administrator, Office of Air and Radiation (June 8, 2007).

20 Letter from Gove rnor Brewer of Arizona to Jared Blumenfeld, Regional Administrator, EPA Region IX (Mar. 23, 2010).

21 Redesignation of West Pinal County as Nonattainment for PM 10 , 77 Fed. Reg. 32024 (May 31, 2012) (codified at 40 C.F.R. pt. 81.303).

December 21, 2015 Final 23

## 3.5 **West Pinal County PM 10**  

## Nona **ttainment Area Description**

The following sections describe the boundary of the nonattainment area and provide information on the geography, climate, population, and economy of Pinal County and the PM 10 planning area.



### 3.5.1 **West Pinal County PM 10**  

### Nonattainment Ar **ea Boundary**

The boundaries of the West Pinal County PM 10 nonattainment area are defined at 40 C

. F

. R

. §
81.303. Figure 3

- 1 below maps the location of th e area.

December 21, 2015 Final 24Figure 3

- 1 Map of West Pinal County PM 10 Nonattainment Area

Source: Arizona Department of Environmental Quality

December 21, 2015 Final 25

### 3.5.2 **Geography and Climate**

Pinal County is located in Central Arizona, lying within a basin between the Phoenix and Tucson metropolitan areas and encompasses approximately 5,365.61 square miles

. 22 The eastern portion of the county is mountainous with elevations up to 6,441 feet, 23 whe reas the western region primarily consists of low desert valleys. The county includes several cities that are primarily located in low desert areas. Table 3

- 2 provides a list of incorporated cities and elevations that are located within Pinal County jurisdiction.

Table 3

- 2 Names and Elevations of West Pinal County Cities

City Name Elevation (ft.)

Apache Junction 1,754

Casa Grande 1,403

Coolidge 1,428 Eloy 1,555

Florence 1,473
Maricopa 1,171
Superior 2,842

Source: How High is Greater Phoenix? 24

The climate is arid in the nonattainment area and the county in general. As a representative example, Casa Grande National Monument average monthly maximum temperatures rang e from 66.0°F to 106.2°F, and the average month ly minimum temperatures rang e from 35.7°F to
75.8°F. 25 The driest time of the year for the County is typically April through June followed by
S eptember through November. Average monthly precipitation ranges from 0.06 1 up to 1.28 inches. Figure 3

- 2 shows the annual average monthly temperatures and precipitation for the Casa Grande National Monument in Pinal County, Arizona.

22 United States Census Bureau, Pinal County, Arizona QuickFacts Beta

, http://quickfacts.census.gov/qfd/states/04/04021.html (last visited Jun. 29, 2015).

23 Report to Citizens for Fiscal Year 2011

- 2012 , (Jun. 29, 2015) http://www.pinalcountyaz.gov/departments/mfr/ documents/reporttocitizens2011_12.pdf .

24 How High is Greater Phoenix , (Jun. 29, 2015) http://phoenix.about.com/od/natureandenvironment/a/elevation _4.htm

. 25 National Centers for Environmental Infor mation, Data Tools: 1981

- 2010

– Casa Grande National Monument,
Arizona (Jun. 29, 2015) http://www.ncdc.noaa.gov/cdo

- web/datatools/normals.

December 21, 2015 Final 26Source: NOAA National Centers for Environmental Information

– Data Tools 26



### 3.5.3 **Population**

According to the Arizona Department of Administration (ADOA), the West Pinal PM10 Nonattainment Area has a total population of 259,141 for the emissions inventory base year
2008. 27 Residence data shows that 136,790 of the population lived in the incorporated areas (Cities/Towns), 34,937 people lived in unincorporated (non

- CDP) areas, and 87,414 lived within the Census Designated Places (CDP). 28 Table 3

- 3 shows the population distribution for each area within the West Pinal County PM10 Nonattainment Area.

26 Id

. 27 Internal Report from the Arizona Department of Administration, October 31, 2013

. 28 Census Designated Places (CDPs) are delineated for the decennial census. CDPs are places that are not legally incorporated and represent the statistical counterparts of incorporated places (e.g. cities/towns).

Figure 3

- 2 Casa Grande National Monument, Arizona, Monthly Average Temperatures and Precipitation: 1981

- 2010 Normals

December 21, 2015 Final 27Table 3

- 3 West Pinal County PM 10 Nonattai nment Area Population Distribution

– 2008 Emissions Inventory Base Year

Place Population Apache Junction City 4 Casa Grande City 48,096 Coolidge City 12,236 Eloy City 14,620
Florence Town 22,574 City of Maricopa 38,794 Queen Creek Town 467
Ak

- Chin Village CDP 5 Arizona City CDP 9,781
Blackwater CDP 0
Cactus Forest CDP 555
Chuichu CDP 0 Gold Canyon CDP 11
Picacho CDP 440
Red Rock CDP 0 San Tan Valley CDP 75,932
Stanfield CDP 691 Total Population within the Nonattainment Area: 259,141

Source: Arizona Department of Administration

- October, 2013, Internal Report



### 3.5.4 **County Economy**

The eastern portion of Pinal County is characterized as copper mining communit ies . The communities of Mammoth, Oracle, San Manuel, and Kearny have traditionally b een active in copper mining, smelting, milling and refining. The towns of Apache Junction, Arizona City, Coolidge, Eloy, and particularly Casa Grande have expanded and diversified their economic base to include manufacturing, trade, and services. 29 This exp ansion of the economy has been facilitated by the location of the area in the major growth corridor between Phoenix and Tucson and also by the growth of Mesa, near Apache Junction. 30

Table 3

- 4 provides a percentage distribution of the total employed population by various sectors. Total civilian employed population has increased by 3.7% since 2010. 31

29 Pinal County Statistics (Jun. 29, 2015), http://www.pinalcountyaz.g ov/ed/businessconnections/Pages/ PinalCountyStatistics.aspx

. 30 Id

. 31 U.S. Census Bureau, American FactFinder

– Selected Economic Characteristics (Jun. 29, 2015), http://factfinder.census.gov/faces/tableservices/jsf/pages/productview.xhtml (deduced from comparing 2010 to 2013 for Pinal County, AZ).

December 21, 2015 Final 28Table 3

- 4 Pinal County Civilian Employed Population 16 Years and Over

– 2013 U.S. Census
Bureau
Industry Population Percentage Agriculture, forestry, fishing and hunting, and mining 5,290 3.8%

Construction 8,708 6.3% Manufacturing 13,831 10.0%

Wholesale trade 2,010 1.5%

Retail trade 18,433 13.4% Transportation and warehousing, and utilities 5,934 4.3%

Information 3,424 2.5%
Finance and insurance, and real estate and rental and leasing 8,659 6.3%

Professional, scientific, and management, and
administrative and waste management services 10,817 7.9%

Educational services, and health care and social
assistance 27,015 19.6%

Arts, entertainment, and recreation, and
accommodation and food services 16,068 11.7%

Other services, except public administration 6,103 4.4%

Public administration 11,470 8.3%
Total Civilian Employed Population 137,762 100.0%

Source: U.S. Census Bureau, 2013. American Community Survey 32

The median household income in Pinal County was $49,756 in 2013. The median household

income decreased by just 0.07% from 2010 to 2013, while the mean increased by 5.65% during
the same timeframe. 33

In 2008, the number of permits issued for residential buildings and units were 3,016 and 3,020, respectively. 34 By 2014, the number of reported permits issued for buildings and units issued decreased to 1,729 and 1,744, respectively. 35 Table 3

- 5 provides a four

- year annual summary of the issued building permits in Pinal County.

32 Id

. 33 Id

. 34 Building Permits, U.S. Census of Bureau, http://censtats.census.gov/bldg/bldgprmt.shtml? (last visited Jun. 15, 2015).

35 Id

.

December 21, 2015 Final 29Table 3

- 5 Annual New Privately

- Owned Residential Building Pe rmits

Year Buildings Units Cost

2014 1,729 1,744 $318,720,727

2013 2,129 2,144 $344,388,193

2012 1,776 1,823 $244,641,995

2011 975 978 $126,271,132

2010 1,597 1,597 $206,850,342

2009 2,182 2,182 $284,576,575

2008 3,016 3,020 $370,613,362

Source: Building Permits

- U.S. Census Bureau 36



## 3.6 **General SIP Approach**

**- Regulatory Requirements and**  **Guidance**

In November 1990, the U.S. Congress enacted a series of amendments to the CAA. One of the primary effects of the revision was to expand and clarify the planning provisions for those areas not meeting the NAAQS. The CAA, as amended, authorizes comprehensive federal and state programs to provide for attainment and maintenance of the NAAQS. Section 3.6.1 outlines CAA requirements for moderate PM 10 nonattainment areas. In addition, EPA has published guidance documents to clarify environmental regulations relating to attainment of the NAAQS and to assist in developing approaches for implementing those regulations. Section 3.6.2 summarizes applicable EPA guidance.



### 3.6.1 **Clean Air Act Requirements for Nonattainment Area Plans**

The 1990 CAA amendments identify specific emission reduction goals, require bot h a demonstration of Reasonable Further Progress (RFP) and attainment, and incorporate more stringent sanctions for failure to attain or to meet interim milestones. CAA Title I Part A, and Title I Part D, Subparts 1 and 4 are applicable to PM 10 plans. Table 3

- 6 lists the CAA requirements and explains how the demonstrations contained in this document satisfy those obligations. Pollutant specific requireme nts for moderate PM 10 nonattainment areas are found in §§ 188 through 190 of the CAA, and the general planning and control requirements for nonattainment area plans are found in CAA §§ 110 and 172.

36 Id

.

December 21, 2015 Final 30Table 3

- 6 Clean Air Act (CAA) Requirements for Moderate PM 10 Nonattainment Area SIPs

CAA Citation Action to Meet Requirement Location in
Document

CAA Title I

– Air Pollution Prevention and Control; Part A

– Air Quality and Emissions Limitations;
Section 110

– Implementation Plans
110(a)(2)(A) Requires that implementation plans “include enforceable emission limitations and other control measures, means, or techniques (including economic incentives such as fees, marketable permits, and auctions of emissions righ ts), as well as schedules and timetables for compliance, as may be necessary or appropriate to meet the applicable requirements of this chapter.”

Chapter 6 describes the measures implemented to reduce PM 10 emissions and ensure future attainment of the NAAQS. Chapter 6

.

CAA Title I

– Air Pollution Prevention and Control; Part D

– Plan Requirements for Nonattainment Areas; Subpart 1

– Nonattainment Areas in General; Section 172. Nonattainment Plan Provisions in General; Subsection 172(c) Nonattainment Plan Provisions
§ 172(c)(1)

– In General “Such plan provisions shall provide for the implementation of all reasonably available control measures [RACM] as expeditiously as practicable (including such reductions in emissions from existing sources in the area as may be obtained through the adoption, at a minimum, of reasonably available control technology [RACT]) and shall provide for attainment of the national primary ambient air quality standards.”

Chapter 6 contains an explanation of applicable RACM for PM 10

sour ces in the nonattainment area. Chapter 7 demonstrates the area will attain the air quality standards with all implemented
controls. Chapter 6 and Chapter 7

.

§ 172(c)(2)

– RFP [Reasonable Further Progress] “Such plan provisions shall require reasonable further progress”
d efined in CAA Sec. 171(1) as “... annual incremental reductions in emissions ... for the purpose of ensuring attainment of the applicable national ambient air quality standards by the applicable date.”

This submittal demonstrates, in accordance with EPA Guida nce, that the West Pinal County Nonattainment Area will achieve required emissions reductions within the required timeframes necessary to attain the PM 10 NAAQS. As such, the RFP Chapter 6 and Appendix D (Attainment TSD)

.

December 21, 2015 Final 31CAA Citation Action to Meet Requirement Location in
Document
requirement is met. Chapter 7 contains emissions projections after application of control strategies. Chapter 6 i ncludes an explanation of measures responsible for the emissions reductions and implementation schedules for each rule

. § 172(c)(3)

– Inventory [Emissions] “Such plan provisions shall include a comprehensive, accurate, current inventory of actual emissions from all sources of the relevant pollutant or pollutants in such area, including such periodic revisions as the Administrator may determine necessary to assure that the requirements of this part are met.”

ADEQ maintains a historical and current database of actual
emissions from State permitted point and area sources. The Pinal County Air Quality Control District maintains a similar database of actual emissions from County permitted sources. All non permitted source emissions data (i.e.: area and mobile sources) were develo ped for this plan. Base

- year and projected
base emissions are contained in Chapter 5

. Chapter 5 and Appendix B (EI TSD).

§ 172(c)(4)

– Identification
and Quantification “Such plan provisions shall expressly identify and quantify the emissions, if any, of any such pollutant or pollutants which will be allowed, in accordance with Section 173(a)(1)(B), from the construction and operation of major new or modified stationary

s ources in each such area. The plan shall demonstrate to the satisfaction of the Administrator that the emissions quantified for this purpose will be consistent with the achievement of reasonable further progress and will not interfere with attainment of t he applicable national ambient air quality standard by the applicable attainment date.”

The permit program requirements of CAA Section 173(a)(1)(B) are applicable to sources located in a “targeted economic development zone” as determined by the Administ rator under consultation with the Secretary of Housing and Urban Development. No such zones are currently known to exist within
the West Pinal Nonattainment Area. No additional
location in
document.

§ 172(c)(5)

– Permits for New
and Modified Major Stationary
Sources “Such plan provisions shall require permits for the construction and operation of new or modified major stationary sources anywhere in the nonattainment area, in accordance with section
173.”

Arizona Revised Statutes Title 49, Chapter 3 , Articles 1, 2, and 3 No additional
location in
document.

December 21, 2015 Final 32CAA Citation Action to Meet Requirement Location in
Document establish ADEQ and local agency authority for preconstruction review and permitting. Under the air permits program, sources that emit regulated pollutants are required to obtain a permit before constructing, changing, replacing, or operating any equipment or process which may cause air pollution. This includes equipment designed to reduce air pollution. Permits are also required if an existing facility that causes air pollution transfers ownership, relocates, or otherwise changes o perations.

Per the authority noted above, all new sources and modifications to existing sources in Arizona are subject to state requirements for preconstruction review and permitting under Arizona Administrative Code (AAC), Title 18, Chapter 2, Articles 2, 3, 4, and 5 or relevant county rules. All new major sources and major modifications to existing major sources in Arizona are also subject to the nonattainment New Source Review (NSR) provisions of these rules or Prevention of Significant
Deterioration (PSD) for attainment areas. Sources under Pinal County jurisdiction are subject to the Pinal County Air Quality Control District, NSR program in Pinal County Code of Regulations, Chapter 3, Permits and Permit Revisions.

ADEQ submitted a revision to the SIP on October 29, 2012, to update its program to comply with all current federal NSR requirements, including NSR reform. On June 29 , 2015, EPA signed a limited approval/limited disapproval (LA/LD) of this SIP
revision. ADEQ is under an obligation to corr ect the deficiencies identified by EPA. Until the corrections are approved, however, the rules subject to the LA/LD will be part of the SIP.

Pinal County has a SIP

- approved PSD program but lacks any form of EPA approval for nonattainment NSR. ADEQ therefo re has original jurisdiction over major sources in Pinal County, but has delegated that jurisdiction to the County under A.R.S. § 49

- 107.

§ 172(c)(6)

– Other Measures “Such plan provisions shall include enforceable emissions limitations, and such other control measures, means or techniques ..., as well as schedules and timetables for compliance, as may be necessary or appropriate to provide for attainment of such standard in such area by the applicable attainment date specified in this part.” Chapter 6 and Chapter 7

.

December 21, 2015 Final 33CAA Citation Action to Meet Requirement Location in
Document

Consistent with CAA requirements and EPA Guidance, this submittal includes emissions limitations, control strategies, and applicable compliance schedules for PM 10 sources in the nonattainment area. Air quality modeling demonstrates that the
area will attain the PM 10 NAAQS with control measures fully implemented. § 172(c)(7)

– Compliance with Section 110(a)(2) “Such plan provisions shall also meet the applicable provisions of Section 110(a)(2).”

The requirements of Section 110(a)(2) are detailed elsewhere in
this Table. No additional
location in
document.

§ 172(c)(8)

– Equivalent Techniques “Upon application by any State, the Administrator may allow the use of equivalent modeling, emission inventory, and planning procedures, unless the Administrator determines that the proposed techniques are, in the aggregate, less effective than the methods specified by the Administrator.”

ADEQ’s intended modeling and emissions inventor y methodologies (Inventory Preparation Plan) were submitted to and reviewed by EPA. Some modifications to the intended methodologies were required to make the plan more scientifically sound. The analyses to establish emissions limits and control strategies were conducted using AERMOD and modified rollback modeling with EPA’s concurrence. Chapter 7

, Chapter 5

, Appendix B (EI TSD), Appendix C ( M odeling TSD) , and Appendix D (Attainment TSD)

.

§ 172(c)(9)

– Contingency
Measures “Such plan shall provide for the implementation of specific

measures to be undertaken if the area fails to make reasonable further progress, or to attain the national primary ambient air quality standard by the attainment date applicable under this part. Such measures shall be included in the plan revision as contingency me asures to take effect in any such case without further action by the State or the Administrator.”

Consistent with EPA guidance, this submittal includes measures (beyond what is necessary to demonstrate attainment) to provide for emissions reductions equiv alent to one year’s average increment of RFP. As such, the contingency measure requirement is met. Chapter 6 and Appendix D (Attainment TSD)

.

December 21, 2015 Final 34CAA Citation Action to Meet Requirement Location in
Document

CAA Title I

– Air Pollution Prevention and Control; Part D

– Plan Requirements for Nonattainment Areas; Subpart 1

– Nonattainment Areas in General; Section 176. Limitations on Certain Federal
Assistance § 176(c)

– [Transportation Conformity] Transportation conformity is required under Clean Air Act section 176(c) [42 U.S.C. 7506(c)] to ensure that federal funding and approval are given to highway and transit projects that are consistent with ("conform to") the air quality goals established by the state air q uality implementation plan (SIP). Conformity, to the purpose of the SIP, means that proposed transportation activities will not: 1) cause new air quality violations, 2) worsen existing violations, or 3) delay timely attainment of the national ambient air q uality standards (including any required interim emission reductions or milestones). 37

The conformity rules at 40 CFR Parts 51.390 and 93 require the SIP to include maximum allowable emissions or a “budget” for

on

- road mobile sources. Projected emission s from future transportation projects are compared to the approved budget to ensure they do not exceed levels demonstrated necessary to attain and maintain the NAAQS.

Discussion of transportation conformity and on

- road motor vehicle emissions budgets for the West Pinal PM 10 planning area
are included in Chapter 5

. Chapter 5

, Section 5.5

.

§ 176(c)

– [General Conformity] Similar to Transportation Conformity, which applies to highways and mass transit projects, General Conformity is applicable to all other federally supported activities to ensure that the actions taken by federal agencies in nonattainment and maintenance

ar eas do not interfere with a state’s plans to meet national air quality standards.

General Conformity for the West Pinal County Nonattainment
Area must be addressed to assure PM 10 emissions from any federal actions or plans do not exceed the rates outline d in 40 CFR 93.153(b) (see 58 FR 63253; November 30, 1993). Criteria for making determinations and provisions for general conformity No other
location in
document.

37 State and Local Transportation Resources (Jun. 29, 2015), http://www.epa.gov/OMS/stateresources/trans conf/ generalinfo.htm.

December 21, 2015 Final 35CAA Citation Action to Meet Requirement Location in
Document

are located in R18

- 2

- 1438 of the Arizona Administrative Code. ADEQ and Pinal County commit to review and comment, as

appr opriate, on any federal agency draft general conformity determination it receives pursuant to 40 CFR 93.155 for activities planned for this air quality planning area.

CAA Title I

– Air Pollution Prevention and Control; Part D

– Plan Requirements for Nonattainment Areas; Subpart 4

– Additional Provisions for Particulate Matter Nonattainment Areas; Section 188. Classifications and Attainment Dates, Section 189. Plan Provisions and Schedules for Plan Submissions, and Section 1 90. Issuance of RACM and BACM Guidance

§ 188(c)(1)

– Attainment
Dates “For a Moderate Area, the attainment date shall be as expeditiously as practicable but no later than the end of the sixth calendar year after the area’s designation as nonattainment, except that, for areas designated nonattainment for PM

– 10 under section 107 (d)(4), the attainment date shall not extend beyond December 31, 1994.”

A p ortion of West Pinal County was redesignated as a “moderate’ nonattainment area effective July 2, 2012. The area is required
to demonstrate attainment no later than the end of December
2018. Chapter 7

.

§ 188(d)

– Extension of
Attainment Date for Moderate
Areas “Upon application by any State, the Administrator may extend for 1 additional year (hereinafter referred to as the “Extension Year”) the date specified in paragraph (c)(1) if

– (1) the State has complied with all requirements and commitments pertaining to the area in the applicable implementation plan; and (2) no more than one exceedance of the 24

- hour national ambient air quality standard level for PM

– 10 has occurred in the area in the year preceding the Extension Year, and the annual mean concentration of PM 10 in the area for such year is less than or equal to the standard level. No more than 2 one

- year extensions may be issued under the subsection for a single nonattainment
area.”

ADEQ is not requesting an extension at this time. No other
location in
document.

December 21, 2015 Final 36CAA Citation Action to Meet Requirement Location in
Document § 189(a)(1)(A)

– Moderate Areas,
Plan Provisions “ For the purpose of meeting the requirements of section 7502(c)(5)..., a permit program providing that permits meeting
the requirements of section 7503 are required for the construction and operation of new and modified major stationary sources of PM

– 10 .”

The State and Pinal County permitting programs are described at “172(c)(5)

– Permits for New and Modified Major Stationar y Sources” of this table. No other
location in
document.

§ 189(a)(1)(B)

– Moderate Areas,
Plan Provisions “ Either: (i) a demonstration (including air quality modeling) that the plan will provide for attainment by the applicable attainment date; or (ii) a demonstration that attainment by such date is impracticable.”

Attainment of the NAAQS is demonstrated through the use of AERMOD and modified rollback modeling. Chapter 7 and Appendix D (Attainment TSD)

.

§ 189(a)(1)(C)

– Moderate Areas,
Plan Provisions “Provisions to assure that reasonably available control measures for the control of PM

– 10 shall be implemented no later than December 10, 1993, or 4 years after designation in the case of an area classified as moderate after the date of the enactment of the Clean Air Act Amendments of 1990 [November 15, 1990].”

Implementation schedules for the West Pin al County reasonably
available control measures are included in Chapter 6

. Chapter 6

.

§ 189(a)(2)(B)

– Moderate Areas,
Schedule for
Plan Submissions “18 months after the designation as nonattainment ...”

This SIP replaces a plan originally submitted on December 30, 2013, a submittal that was later withdrawn. No other
location in
document.

§ 189(c)(1)

– Milestones “Plan revisions demonstrating attainment submitted to the Administrator for approval under this subpart shall contain quantitative milestones which are to be achieved every 3 years until the area is redesignated attainment and which demonstrate
reasonable further progress, as defined in section 171 (1) , toward
attainment by the applicable date.”

Emissions reduction milestones are included in Chapter 7

. Chapter 7

.

December 21, 2015 Final 37CAA Citation Action to Meet Requirement Location in
Document § 189(c)(2)

– Milestones “ Not later than 90 days after the date on which a milestone applicable to the area occurs, each State in which all or part of
such area is located shall submit to the Administrator a demonstration that all measures in the plan approved under this section have been implemented and that the milestone has been
met. A demonstration under this subsection shall be submitted in such form and manner, and shall contain such info rmation and analysis, as the Administrator shall require. The Administrator
shall determine whether or not a State’s demonstration under this subsection is adequate within 90 days after the Administrator’s receipt of a demonstration which contains the info rmation and analysis required by the Administrator.”

ADEQ commits to submit all required demonstrations

. No other
location in
document.

§ 189(c)(3)

– Milestones “ If a State fails to submit a demonstration under paragraph (2) with respect to a milestone within the required period or if the Administrator determines that the area has not met any applicable milestone, the Administrator shall require the State, within 9 months after such failure or determination to submit a plan revision that assures that the State will achieve the next milestone (or attain the national ambient air quality standard for

PM

– 10 , if there is no next milestone) by the applicable date.”

ADEQ commits to submit all required demonstrations. No other
location in
document.

§ 189(e)

– PM

– 10
Precursors “The control requirements applicable under plans in effect under this part for major stationary sources of PM

– 10 shall also apply to major stationary sources of PM

– 10 precursors, except where
the Administrator determines that such sources do not contribute significantly to PM

– 10 levels which exceed the standard in the area. The Administrator shall issue guidelines regarding the application of the preceding sentence.”

ADEQ determined that emissions of PM 10 precursors do not contribute sign ificantly to exceedances of the NAAQS in the West Pinal Nonattainment Area. See Appendix B (EI TSD), Exhibit 16 (Precursor Emission Summary) for details of the analysis. Appendix B (EI TSD), Exhibit
16 (Precursor
Emission Summary)

§ 190

– Issuance of RACM and
BACM Guidance “The Administrator shall issue, in the same manner and according to the same procedure as guidance is issued under section 108 (c)

, technical guidance on reasonably available control measures and best available control measures for urban fugitive dust, and emissions from residential wood combustion...” Chapter 3

, Section 3.6.2

December 21, 2015 Final 38CAA Citation Action to Meet Requirement Location in
Document ADEQ employed appropriate EPA guidance in the development of this plan.



### 3.6.2 **EPA Guidance**

The guidance documents utilized in the preparation of this plan include:

• Emissions Inventory Guidance for Implementation of Ozone and Particulate Matter National Ambient Air Quality Standards (NAAQS) and Regional Haze Regulations . U.S. Environmental Protection Agency. EPA

- 454/R

- 05

- 001. August 2005.

• PM 10 SIP Development Guideline . U.S. Environmental Protection Agency. EPA

- 450/2

- 86

- 001. June 1987.

• PM

- 10 Guideline Document . U.S. Environmental Protection Agency. EPA

- 452/R

- 93

- 008. April 1993.

• State Implementation Plans; General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990 . U.S. Environmental Protection Agency. 57 Feder al Register 13498; April 16, 1992.

• State Implementation Plans; General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990; Supplemental . U.S. Environmental Protection Agency. 57 Federal Register 18070; April 28, 1992.

• State Implementation Plans for Serious PM

- 10 Nonattainment Areas, and Attainment Date Waivers for PM

- 10 Nonattainment Areas Generally; Addendum to the General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990

. U.S. Environm ental Protection Agency. 59 Federal Register 41998; August 16, 1994.

December 21, 2015 Final 39

## (This page is intentionally blank.)

December 21, 2015 Final 40

## 4 **AMBIENT AIR QUALITY MONITORING**

The primary goal of the PM 10 monitoring network in Pinal County is to collect ambient data necessary to determine com pliance with the PM 10 NAAQS and fulfill the regulatory requirements for PM 10 monitoring in the nonattainment area.

This chapter provides a general description of the monitoring sites, equipment, a historic data summary, and current 24

- hour NAAQS complianc e in the West Pinal PM 10 Nonattainment Area.



## 4.1 **Monitoring Site, Equipment, and Quality Assurance**  **Procedures**

Arizona’s air monitoring network consists of state and local stations operated according to the requirements of 40 CFR Part 58. Collected data are q uality assured and reported to EPA’s Air Quality System (AQS) for comparison to the NAAQS. Pinal County maintains authority to conduct ambient surveillance under ARS § 49

- 473 and Pinal County Code, Section 1

- 1

- 040. In February of 2013, ADEQ and PCAQCD ente red into a memorandum of agreement to clarify and define the responsibilities of a Primary Quality Assurance Organization (PQAO). 38

Pinal County uses Federal Reference Method (FRM) monitors to collect filter based PM 10 and automated Federal Equivalent Metho d (FEM) monitors for recording continuous PM 10 . Historically three types of PM 10 monitors have been used throughout the Pinal County monitoring network: (1) filter

- based, high

- volume samplers, (2) filter based

, medium

- volume samplers, and (3) Tapered Eleme nt Oscillating Microbalance (TEOM) monitors which measure

PM 10 on a continuous basis. Currently 8 monitors are in operation in the West Pinal County

PM 10 planning area ; 6 continuous and 2 filter based medium

- volume units with periodic sampling. 39 Several of the TEOM sites have also operated filter monitors prior to installation of continuous monitoring.

The installed monitors are maintained in accordance with federal siting and design criteria 40

and are consistent with the Pinal County Air Quality Control D istrict, 2014 Ambient Monitoring Network Plan and 2013 Data Summary, approved by EPA for the West Pinal area on October 29, 2014.

Figure 4

- 1 maps the locations of monitoring sites located within the West Pinal Nonattainment
Area. Table 4

- 1 provides site descriptions for these monitors.

38 Memorandum of Agreement No. ADEQ 13

- 033141(Feb. 13, 2013), available at http://agendasearch.pinalcounty az. gov/AttachmentViewer.aspx?AttachmentID=14187&ItemID=9048.

39 There are no longer any high

- volume samplers in the West Pinal PM 10 Nonattainment Area; however, data from past measurements are still used to calculate design values for comparison to the NAAQS.

40 Network Design Criteria for Ambient Air Quality Monitoring are located in 40 C.F.R. Part 58, Appendix D. Probe
and Monit oring Path Siting Criteria for Ambient Air Quality Monitoring are found in 40 C.F.R. Part 58, Appendix A.

December 21, 2015 Final 41Figure 4

- 1 West Pinal County PM 10 Nonattainment Area

Source: Arizona Department of Environmental Quality

December 21, 2015 Final 42Table 4

- 1 Active Monitors within the West Pinal County PM 10 Nonattainment Area

AQS ID Site Name Latitude Longitude Classification

41 Monitor Type Street Address City

04

- 021

- 0001 Casa Grande
Downtown +32.877583 - 111.752222 SLAMS TEOM 401 N Marshall St. Casa Grande

04

- 021

- 3009 Combs School +33.219111 - 111.561111 SLAMS TEOM 301 E Combs Rd Queen Creek

04

- 021

- 3004 Coolidge
Maintenance Yard +32.978556 - 111.514833 SLAMS Medium

Volume

42 212 E Broadway Coolidge

04

- 021

- 3013 Cowtown Road +33.010530 - 111.972050 SPM 43 TEOM 37580 W Maricopa Maricopa

04

- 021

- 3014 Eloy County Complex +32.757639 - 111.554861 SLAMS Medium

Volume

44 801 N Main
St Eloy

04

- 021

- 3010 Maricopa County Complex (City of Maricopa) +33.010530 - 111.972050 SLAMS TEOM 44625 W Garvey Rd Maricopa

04

- 021

- Pinal County Housing +32.891056

- SLAMS TEOM 970 N 11 Casa Grande

41 SLAMS is defined at 40 C.F.R. 58.1 as a “State or local air monitoring stations(s).” Data from SLAMS sites are primarily used for comparison to the NAAQS. SPM or Special Purpose Monitors are generally monitors established for use in special studies and are not used to show compli ance with minimum network requirements in 40 C.F.R. 58 (e.g. number and siting of monitors).

42 The 2014 Pinal County Networ k Plan identifies collocated medium

- volume PM 10 samplers at the Coolidge Maintenance Yard effective July 1, 2013. The samplers operate (collect data) on a one in six

- day schedule. Prior to this date, a high volume sampler was operated at this site.

43 The C owtown monitor is currently designated as a special purpose monitor (SPM). During its review of the 2012 Pinal County Network Plan, EPA commented that because the site has been active for longer than 24 months [and can be used for comparison to the NAAQS] it should be designated as a SLAMS monitor. Pinal County proposed to retain the SPM designation pending completion of a relocation process currently underway. See the Pinal County Air Quality Control District, 2014 Ambient Monitoring Network Plan and 2013 Data Summary for more information.

44 The 2014 Pinal County Network Plan identifies a single medium

- volume PM 10 sampler at the Eloy County Complex effective July 1, 2013. The sampler operates (collects data) on a one in six

- day schedule. Prior to this date, a high volume sampler was operated at this site.

December 21, 2015 Final 43AQS ID Site Name Latitude Longitude Classification

41 Monitor Type Street Address City

3011 Complex 111.570500 Mile Rd

04

- 021

- 3008 Stanfield County Complex +32.881194 - 111.962000 SLAMS TEOM 36697 W Papago Rd Stanfield

Source: US EPA Site Description Report

- May 7, 2013; updated May 2015 based on Pinal County’s 2014 Ambient Monitoring Network Plan.

December 21, 2015 Final 44

## 4.2 **Historical PM 10**  

## Data Summary

EPA defines an “exceedance” as a discrete event, where a measured value at a monitor is higher than the level of the standard. The standard is attained when the expected number of days per calendar year with a 24

- hour averag e concentration above 150 μg/m 3 is equal to or
less than one . T he number of expected exceedances at a site is determined by recording the number of exceedances in each calendar year and t hen averaging them over the most recent 3

year period

. 45

Non

- continuous filter based samplers operate on a schedule based on the level of tha t monitoring site ’s ambient concentration s relative to the 24

- hour standard

. The required sampling schedule can range from every day to a minimum of once every six th day

. Because some monitoring locations do not record a value for each day of the year, a n adjustment is made to the data collected to estimat e the number of exceedances for that calendar year . To make the adjustment, it is assumed that the fraction of missing values (un

- sampled days) that
would have exceeded the level of the standard is identical to the fraction of measured values
above this level. For example, one exceedance recorded by a one in six day monitor would count as 6.1 exceedances for that calendar year. 46

Figure 4

- 2 shows the three

- year average expected rate of exceedance for the current West Pinal monitor ing network for years 2006 through 2014. The values presented from the Coolidge and Eloy monitoring sites are results f rom filter based PM 10 samplers which collect samples on a one in six

- day schedule . The six other monitoring sites, Casa Grande Downtown

, Combs

, Cowtow n, Maricopa

, Pinal County Housing , and Stanfield represent continuous data that were processed by PM 10 TEO M air monitoring instrumentation.

45 24

- hour values as calculated rounding to the nearest 10 μg/m 3 , according to 40 C.F.R. § 50, Appendix K (2015) (effective 2006).

46 See National primary and secondary ambient air quality standards for PM 10 , 40 C.F.R. § 50.6; Interpretation of the National Ambient Air Quality Standards for Particulate Matter, 40 C.F.R. § 50, Appendix K (2015) (effective 2006).

December 21, 2015 Final 45Figure 4

- 2 Three

- Year Average Expected Rate of Exceedance

Source: U.S. EPA Air Quality System 47



## 4.3 **24**

**- Hours PM**  **10** 

## NAAQS Compliance

**- 2012** 

**- 2014** 

As noted above, the 24

- hour PM 10 standard is met when the expected number of exceedances per year at each monitoring site is less than or equal to one on average over a three year period

. Based on complete quality

- assured data for 2012

- 2014, the West Pinal County area is
not currentl y meeting the PM 10 NAAQS. The findings indicate that all six monitoring stations
that use continuous PM 10 TEOM samplers yielded a three

- year average expected rate of exceedance greater than one. The monitoring station at Cowtown recorded the highest three

year average expected rate of exceedance at 64 followed by the Stanfield monitor, which has a
three

- year average exceedance rate of 13

. The filter based monitors at Coolidge and Eloy recorded no violations of the NAAQS.

47 2005

- 2014 Preliminary Design Value Report obtained on May 13, 2015. Data excludes regional (exceptional) events concurred by EPA. 79.3 142.7 201.2

139.8

86.1

60.7 63.0 75.7

64

0 15 30 45 60 75 90 105 120 135 150 165 180 195 210

2005 2006 2007 2008 2009 2010 2011 2012 2013 2014Three-Year Average Expected Rate of Exceedance

Year Casa Grande Downtown

Combs School

Cowtown Road
Marciopa County Complex
Pinal County Housing Complex
Stanfield County Complex
Coolidge Maintence Yard
Eloy County Complex

December 21, 2015 Final 46Table 4

- 2 below includes a summary of the most recent three

- year average expected rate of
exceedance for each of the West Pinal monitors.

Table 4

- 2 2012 to 2014 Maximum 24

- Hour Average PM 10 Compliance

AQS ID Site Name 2012 2013 2014 Three

- Year Avg Exp. Rate of Exc. Max
24

- Hr

Avg Exp.
Exc. Max
24

- Hr

Avg Exp.
Exc. Max

24

- Hr

Avg Exp.
Exc.

04

- 021

- 0001 Casa Grande
Downtown 235 2 301 4 929 5 4

04

- 021

- 3009 Combs 205 5.1 299 3 247 5 4

04

- 021

- 3004 Coolidge 134 0 139 0 109 0 0

04

- 021

- 3013 Cowtown 698 60.7 1006 67.5 540 63.9 64 .0

04

- 021

- 3014 Eloy 120 0 107 0 80 0 0

04

- 021

- 3010 City of Maricopa Complex (City
of Maricopa) 256 8.6 333 4 238 2 5

04

- 021

- 3011 Pinal County Housing 541 5 241 5.1 402 6.1 5

04

- 021

- 3008 Stanfield 339 12.1 912 17 342 9.2 1 3

Exp

. – Expected. Exc

. – Exceedance. Source: U.S. EPA Air Quality System 48

48 AMP 450 report (Quick Look Criteria Parameters) and AMP 480 report (Design Value Report) dated July 23, 2015.

December 21, 2015 Final 47

## 5 **ANNUAL EMISSIONS INVENTORY**

This section addresses the requirement to develop an annual baseline emissions inventory for
the entire PM 10 nonattainment area, whereas the attainment modeling summary in Chapter 7 addresses the design day input inventories specific to each monitor.

Section 172(c)(3) of the CAA requires that the base year inventory be a comprehensive, accurate, and current inventory of actual emissions in the nonattainm ent area. An annual emissions inventory helps identify which sources and source categories predominate in the generation of PM10 emissions across the nonattainment area. This ranking of source significance provides the basis for analysis of long

- term emission trends impacted by changes in source activity rates and implementation of regulatory control strategies.

Through discussions between U.S. EPA, the Arizona Department of E nvironmental Quality (ADEQ), and the Pinal County Air Quality Control District (PCAQCD), a base year of 2008 was selected for the preparation of an emission inventory and an attainment demonstration. During 2008, exceedances of the 24

- hour PM 2.5 NAAQS were recorded at Cowtown; exceedances of
the 24

- hour PM10 NAAQS were recorded at Maricopa, Cowtown, Stanfield, Casa Grande, Combs School, and Pinal County Housing. 49 Therefore, inventory calculations were based on
affects on these monitors. Precursor emissions are discussed further in the precursor emission summary discussion located in Exhibit 16 of Appendix B, Emission Inventory Technical Support
Documen t.



## 5.1 **Meteorological Scenarios and General Methodology**

Inventory analysis showed that two scenarios produce emi ssions and contribute to
concentrations in excess of the 24

- hour PM 10 National Ambient Air Quality Standard (NAAQS) of 150μg/m 3 : windblown generation and activity

- based generation. Separate and distinct sources contribute to each of the two emission genera ting scenarios, although there is some overlap
between the sources. Therefore, ADEQ developed two different inventories for each base year

to sum the total annual emissions.

During wind conditions 12 mph or higher , sources with disturbed soil spread a larg e proportion of the emissions throughout the nonattainment area (e.g. unpaved roads, fallow fields, etc.). Some source categorical activities release PM 10 with or without wind because of their dust generating nature (e.g. earthmoving activities during cons truction and agricultural operations

or driving on unpaved roads).

T he spatial distribution of estimated PM 10 emissions within the nonattainment area was facilitated by GIS shapefile s produced by PCAQCD and ADEQ

. Shapefiles for population were

49 Appendix A (Inventory Preparation Plan) A1

- A2.

December 21, 2015 Final 48provided by Arizona Department of Administration. MAG provided paved road and on

- roa d
emission information. Sierra R esearch modeled nonroad emissions using EPA model default data for Pinal County . For other source categories (e.g., construction, confined animal feeding operations (CAFO), and railroads), emission estimates are based on activity rates of sources within the nonattainment area and emissions factors representative of these sources. 50 Where appropriate, local precipitation event data were factored into the annual fugitive dust emissions calculations according to EPA guidance (e.g., such as reported for paved and unpaved
road emissions in AP

- 42 51 ). 52



## 5.2 **Windblown Methodologies for the**  **Base Years 2008 and**
**2018**

**5.2.1 Annual Windblown Methodologies** 

Windblown emissi ons were calculated using a modified version of the methodology described
in the Maricopa Association of Governments ’ (MAG ’s ) 2012 5% Plan, as a function of land use disturbance ratios and wind spee d

. 53 ADEQ determined adoption of the MAG windblown dust

m ethodology as the most appropriate EPA approved windblown dust emission estimation methodology available. This is due to the similar meteorological characteristics of these neighboring counties and to provide consistency between the emission estimates for these two abutting PM 10 nonattainment areas. Generally, the annual emissions are a summed function of the following actions: 54

( a ) each parcel in the nonattainment area was assigned a land use category with a distinct stable to disturbed land ratio,

( b ) individual parcels were assigned the meteorological characteristics (i.e. wind speed and precipitation) of the closest nonattainment area monitor,

( c ) friction velocities were calculated for hourly binned wind speeds,

( d ) friction velocities were then converted to wind speed dependent emission rates for
disturbed and stable lands

, ( e ) high wind event emission rates were adjusted to account for temporal variability in particle saltation and reservoir depletion, and finally

50 See Appendix B (EI TSD) Section 5 Introduction.

51 Compilation of Air Pollutant Emissions Factors, AP

- 42 , U.S. EPA, http://www.epa.gov/ttn/chief/ap42/index.h tml (last visited July 29, 2013).

52 See Appendix B (EI TSD) Section 5.

53 See Appendix B (EI TSD) Section 3.1.2.

54 For an example calculation for windblown dust calculations specific to modeling design day calculations, but similar to this methodology, plea se see Chapter 7 Section 7.1.2.4

.

December 21, 2015 Final 49( f ) individual wind event emi ssions were calculated based on wind speeds and on adjusted hourly emissions rates for each parcel and summed over the entire year.

**a. Assigning Each Parcel to a Land Use Category** 

To account for land use differences and corresponding variances in the ratio o f disturbed versus stable land, each parcel was allocated to a particular land use category. See Table 5

- 1 for a list of the land use categories for w indblown emissions.

Table 5

- 1 Land Use Categories for Windblown Emissions
Developed Urban Lands 55 Developed Rural Lands (low density residential)
Paved Roads 56
Unpaved Roads
Cleared Areas
Residential Construction

Dairies

CAFOs
Desert Shrubland Agriculture
Commercial Construction
Other Site Development

Pinal County Air Quality Control District (PCAQCD) generally assigned a ratio of disturbed versus
stable for each land use type according to predicted or regulated use of land and local expertise. However, for some land use categories such as agricultural crops, construction land use, and unpaved road

, disturbed versus stable ratios had to be deduced more complexly
because of rati o variability within the land use

.

5.2.1.1.1 Agricultural crop land use category ratio 57

The agriculture crop land use category’s disturbed versus stable ratio depends on the crop distribution (barley, corn, cotton, etc.) and corresponding crop stage (i.e. planting , harvesting, growing season, and between harvest and planting) ADEQ used GIS shapefiles, the 2007 USDA Agricultural Census, and a PCAQCD supplied crop calendar to determine the distribution of disturbance levels by crop type across the year. Once the crop distribution and associated crop specific stability ratio within the nonattainment area were determined , ADEQ calculated the

55 Not e that unpaved parking is not included in this land use category list, although it is listed as an activity for activity

- based emissions. For windblown emissions, unpaved parking is enveloped within windblown dust subtotals from Developed Urban, Developed Rural, and Cleared Areas land use categories.

56 The disturbance (and therefore the emission rate) for paved roads was essentially zero because of paved road maintenance within Pinal County. See Appendix B (EI TSD) Section 3.1.2, Table 3

- 46, fn. 103.

57 See Appendix B (EI TSD) Section 5.2

- Agricultural.

December 21, 2015 Final 50annual weighted average of disturbed and stable land for all agricultural cropland in the
nonattainment area . These two weighted a verages were assigned to each parcel in the nonattainment area for the crop land category.

5.2.1.1.2 Construction land use categories ratios 58

Construction ratios varied depending the type of construction occurr ing on each parcel (i.e. residential, com mercial, or site development). ADEQ utilized recommended assumptions from the WRAP Fugitive Dust Handbook to determine the percentage of land on an active site that is disturbed during construction. This percentage of land was adjusted to account for dust suppression controls on construction sites in 2008.

5.2.1.1.3 Unpaved roads land use ratio 59

Road square footage within the nonattainment area was derived from a road ne twork provided by Pinal County. Unpaved road disturbance level varies depending on whether the roa ds in question are private, public, agriculture roads, or trails. For all roads types except public, the roadway was considered fully disturbed. Due to regular maintenance on public roadways, these roadways were assumed to be 75% disturbed and 25% stable.

**b. Grouping Parcels by Distance to Assign Meteorological Data**  **60**

Emission rates are wind speed dependent, therefore, assigning the most accurate meteorological data as possible to each parcel is crucial to determine an accurate emission rate. In order to assign meteorological data, each land parcel in the nonattainment area was grouped to whichever of the six violating PM 10 nonattainment area monitoring sites was closest as measured from the center point of the parcel to the monitor.

**c. Calculation of Friction Ve**  **locity for Wind Speed Bins**

Friction velocity is the shear stress

, or, the force of friction imposed by a fluid ’s flow (in this case wind) passing over a parallel boundary surface (in this case the Earth’s rough planar surface )

,
re

- phrased in units of veloc ity. 61 It becomes relevant to determine speed dependent friction
velocities for calculation of emission rates. Sierra Research determined threshold friction velocity utilizing previously reported methods and data

. The threshold friction velocity is the min imum speed at which windblown dust emissions are initiated at ground level, and it will often depe nd on the impacted soil types. 62 MAG’s previous

58 See Appendix B (EI TSD) Section 5.2

- Construction.

59 See Appendix B (EI TSD) Section 3.1.2 for more information.

60 See Appendix B (EI TSD) Section 5.2 for more information.

61 See generally

, C LAYTON T. C ROWE , ET AL ., E NGINEERING F LUID M ECHANICS 281

- 301 (Jennifer Welter et al. eds., 9th ed. 2009).

62 See Maricopa County, 2008 Maricopa PM10 Periodic Emission Inventory, Appendix 4, 4

- 4 available at http://www.maricopa.gov/aq/divisions/planning_analysis/docs/2008_PM10/App4_WindblownDust.pdf

.

December 21, 2015 Final 51analysis of non

- agricultural land use soils

, 63 and Sierra Research ’s subsequent analysis of agricultural land use soils

, 64 show that all soils throughout the nonattainment area display similar relationships concerning wind speeds and corresponding PM 10 concentrations. Examination of local PM 10 concentration and meteorological monitoring show that when wind speeds a re 12 mph or higher, average PM 10 concentrations are consistently higher than concentrations at lower speeds. 65 Therefore, throughout the emission inventory analysis (and attainment analysis), ADEQ follows MAG’s conclusion that 12 mph is a valid approximat ion of the threshold 10 meter wind speed required for the initiation of windblown dust in the nonattainment area. Therefore, ADEQ concludes that 12 mph or more is a high wind speed.

Recorded wind speeds were first normalized to speeds to a 10 meter measur ement height because wind speeds change with the height from the earth’s surface due to a lessening of surface roughness friction drag with increased height from the surface

. 66 To normalize the recorded wind speeds to the same height of 10 meters, ADEQ con verted wind speeds at the height they were recorded to speeds at 10 meters by using the wind profile power law equation so that the measured speed heights would be consistent with the applicable fluid dynamics equation to convert the wind speeds in the fri ction velocities . ADEQ then grouped these speeds into one mph wind speed bins (i.e. 12, 13, 14). 67 The resulting whole number 10 meter speeds were used for all ensuing calculations throughout the nonattainment area.

Each wind bin speed was subsequently converted to friction velocities for further calculations. To do this, ADEQ relied on previous wind tunnel studies conducted in Arizona. The studies
resulted in a nonattainment

- wide applicable coefficient to allow conversion of 10 meter wind speeds into friction velocities using a speed dependent equation. 68

**d. Converting Friction Velocities to Emission Rates (Vertical Flux Rate)** 

Emission factors calculated previous to the initiation of this plan were applied to all disturbed soils throughout the nonattainm ent area. These emission factors were based on wind tunnel studies of disturbed exposed soils in Maricopa and Pinal Counties. These factors were proportionally modified to account for stable soils, based on another study conducted in Barstow, California. 69

63 Id. at 4

- 5.

64 See Appendix B, Exhibit BVI for more information.

65 See generally “ E v a l u a t i o n o f A e ro s o l P rod u cti o n P o te n tial o f T y p e S u r f a c es in A r iz o n a , ” pr e p a r ed f o r E ng i n ee r i n g

S c ie n ce b y W

. G. Nic k li n g a n d J

. A

. G i lli e s , f o r E P A C o n t r act N o

. 68

- 02

- 380

, Se p te m b er 1986 . See Appendix B, Exhibits
BV and BVI.

66 See generally E NGINEERING F LUID M ECHANICS , supra note 61

. 67 This approach is unlike in the mag plan where they grouped wind speeds in 5 mph bins because no speeds above 25 mph were recorded at Pinal County Housing ov er the 2008 year, hence all the high wind speeds were grouped within just two 5 mph bins, allowing for only limited emission rate accuracy. See Appendix B, Exhibit BV for more
information.

68 See Appendix B (EI TSD), Exhibit BVI for more information regardi ng the Prandtl equation.

69 2008 Maricopa PM10 Periodic Emission Inventory, supra note 62 at 4

- 8.

December 21, 2015 Final 52The Arizona wind tunnel studies provided limited information on emission rates from stable
soils. 70 However, the results of similar studies conducted in Barstow, California indicated that the stable soil produced emissions at a rate of about 12 to 20% of the disturbed soil. 71 Therefore, after the disturbed soil emission factors were computed, the Barstow emission factor ratio (varying between the aforementioned percentages) was applied to the disturbed soil emission factors, in order to compute the emissio n factors for each wind bin speed. 72

For various data availability reasons, emission factors for disturbed and stable soils were computed for both (and only) the Pinal County Housing and the Stanfield monitors. The other four monitors were grouped to either the emission factors computed for PCH or to those for Stanfield, depending on which of the two monitors was closest. These emission factors were then applied to the wind speed bins (velocities) and ensuing pa rcels for each of the monitors.

**e. Emission Adjustment Factor Application**  **73**

Additionally, in the high wind annual calculation process ADEQ appl ied an adjustment factor to account for temporal va riation of emission rates during a wind event . Windblown emissio n factors are generally an estimation of maximum emission potential and, thus, are not always representative of the actual environment. Specifically, land use dependent emission factors assume static emission rates for a given wind speed throughout the pro gression of a wind event. In reality, emission rates vary with time as well as wind speed for reasons such as lack of airborne particles available for re

- entrainment (beginning of wind event) or reservoir depletion of ground particles (end of wind event). Therefore, ADEQ applied distribution curves to the estimated emissions during criterial high wind events throughout 2008 to more accurately represent 2008 annual emissions.

**f. Sum of High Wind Emissions**  **74**

As a last step, for each parcel, individual wind event emissions were calculated based on wind speeds and adjusted hourly emissions rates

. These parcel specific emissions were then summed over the entire year of 2008.



### 5.2.2 **Adjusting and Projecting the 2008 Base Year Emissions to 2018**

The disturbed versus stable r atios for the above described land use categories were adjusted to project emissions from 2008 to 2018. Adjusting these ratios varied depending on land use. For example, some concentrated animal feeding operations (CAFOs) have closed since 2008 and are

p rojected to be cleared areas in 2018. Unpaved roads that have either undergone or are scheduled in Transportation Infrastructure Plans (TIPs) to undergo improvements such as

70 Id

. 71 Id

. 72 Appendix B (EI TSD), Exhibit BV

- 3.

73 For more information, see Appendix B (EI TSD), Exhibit BVII.

74 Note that high wind events with .01 inches or more of recorded precipitation at a monitor were not included.

December 21, 2015 Final 53paving were assigned controlled emissions rates dependent on the control applied. For construction, analysis of permit issuance and projected population grow th was used to adjust
emissions to 2018. 75



## 5.3 **Activity**

**- Based Emissions**  **for the Base**  **Years 2008 and**
**2018**

Below are short summary glimpses as to how activity emissions were calculated for the
nonattainment area annual inventor ies . These emissions calculations do not take wind into account. Emissions for each category presented in Table 5

- 2 were calculated for one year and results from each category were summed to represent all activity emissions within the
nonattainment area over an entire year. More information is in the Emission Inventory TSD in the sections cited for each categor y below.

Table 5

- 2 Activity

- Based Emission Source Categories
Ag Fields ( Harvesting & Tilling )

CAFOs
Dair ies
Paved Road Unpaved Road (Public, Private, Agricultural, and Trails)
Nonroad
Railroad

Construction (Residential, Commercial, Road, and Site Development)
Permitted Sources Fuel Combustion ( Residential ) Fires (Agricultural, Wildfires, and Prescribed Fires) Open Burning (Residential, Commercial, and Land Clearing) Unpaved Parking



### 5.3.1 **Agriculture Crop Emissions**

**a. Generally** 

To compute annual emissions within the entire nonattainment area, ADEQ relied on estimates of the annually harvested crop distribution from the 2007 USDA Agricultural Census for major crops within Pinal County

. This crop distribution was then scaled to the nonattainment area based on the ratio of crop agricultural lands identified in the PCAQCD/ADEQ land use map for

75 For more information, see Appendix B (EI TSD) Sections 5.1.7 and 5.2.

December 21, 2015 Final 54the nonattainment area and the total acreage reported harvested in the 2007 USDA Agricultural Census fo r the County.

Tillage activity emissions were calculated using a n AP

- 42 tillage emission factor equation as used in ADEQ’s 2001Agricultural BMP TSD, 76 taking into account local Pinal county silt content and the closest estimate particle size. Th e emission factor results were then multiplied by the total estimated number of crop

- specific acre

- passes related to local West Pinal tilling
activities. 77

Harvesting emissions were estimated using crop

- specific emission factor equations promulgated by California Air Resources Board, factoring local harvesting activity on each crop specific parcel and respective acreage, per year. 78

**b. Projecting Emissions to 2018** 

For the 2018 annual inventory, no change was made to the amount of land under cultivation or the methods emp loyed in the 2008 calculations. Agricultural emissions were held constant
from 2008 to 2018. 79



### 5.3.2 **Concentrated Animal Feeding Operations (CAFO) Emissions**

**a. Generally** 

Annual PM 10 emissions generated by CAFOs within the nonattainment area in 2008 were computed u sing an average daily PM 10 emission factor ; 80 and 2008 animal population averages for affected facilities were provided by representatives of the Arizona Cattle Feeders
Association. 81

**b. Factoring growth between 2008 and 2018**  While the same method was used a s for 2008, the estimates of the cattle population were
revised to address the closure of feedlots that have occurred to date. For windblown PM10 emissions estimations, these locations were assumed to transition from the CAFO land use to
Cleared Areas. Pro jected animal populations were supplied by industry contact. 82 ADEQ has confirmed through aerial photography and site visits that these facilities no longer exist

.

76 Section 9.1 of AP

- 42 (U.S. EPA, 1995)

77 See Appendix B (EI TSD) Section 3.1.1.1 for more information.

78 Id

. 79 See Appendix B (EI TSD) Section 5.1.1 for more information.

80 This emission factor is further described in Section 3.1.1.2 of Appendix B (EI TSD).

81 See Appendix B (EI TSD) Sections 3.1.1.2 and 5.1.2.

82 Id

.

December 21, 2015 Final 55

### 5.3.3 **Dairy Emissions**

**a. Generally** 

Annual PM 10 emissions for dairy operations in the nonattainment area in 2008 were derived from an emission factor published by the Arizona Governor’s Agricultural BMP Committee

, and estimates of average annual animal populations at affected dairies provided by United Dairymen of Arizona

. 83

**b. Factoring growth between 2008 and 2018** 

The emission estimates employed in the 2008 inventory were held constant for 2018 ; however,
the estimated number of head decrease d from 71,624 in 2008 to 70,644 in 2018 due to facility
closure

.



### 5.3.4 **Fugitive Dust and Exhaust Emissions from Paved Roads**

**a. Generally** 

The new AP

- 42 equation published by EPA in January 2011, 84 a function of silt loading values and the average weight of vehicles traveling on paved roads, was applied to estimate
reentrained PM 10 emissions from paved roads in the nonattainment area. The silt loadings and average vehicle weights were derived from the MAG 2012 Five Percent Plan for PM

- 10. Paved roads were split into four different silt loading categories, producing four differen t PM 10 emission factors from the AP

- 42 equation. These emission factors were applied to estimated road segment specific vehicle miles traveled (VMT) values to produce 2008 fugitive dust particulate emissions from paved roads for the West Pinal PM 10 nonatt ainment area. The
estimated 2008 VMT values for the West Pinal PM 10 nonattainment were obtained from MAG’s TransCAD model outputs for the year 20 08 in the nonattainment area

. 85 For those road segments identified by PCAQCD as containing trackout, the emissio n factor was increased 381%
as described in section 3.1.1.6 of Appendix B . Paved road reentrained fugitive dust was then summed for all road segments in the nonattainment area.

Vehicle exhaust, tire, brake, and starting emissions were calculated using MOVE S inventory simulations. 86 Bow wake emissions from large trucks was estimated by applying a Sierra Research developed emission rate formula 87 to roadways identified by the Arizona Department of Transportation (ADOT) as having significant heavy duty vehicle traffic and unpaved road
shoulders.

83 See Appendix B (EI TSD) Section 5.1.9 for more information.

84 Section 13.2.1 of AP

- 42.

85 See Appendix B (EI TSD) Section 5.1.3 for more information.

86 Id

. 87 “Cost

- Effectiveness of Selected PM 10 Control Measures,” prepared for Maricopa Association of Governments by Sierra Research, June 2006, p. 26.

December 21, 2015 Final 56**b. Factoring growth between 2008 and 2018** 

2018 paved road segment VMT values were interpolated from MAG’s T ransCAD model results
for 2015 and 202 5

. 88 The travel network links and road categories were defined from MAG’s
2015 model results.

Road segments identified to contain trackout or produce bow wake emissions in 2008 were also
assumed to do so in 2018.



### 5.3.5 **Fugitive Dust and Exhaust Emissions from Unpaved Roads**

**a. Generally** 

AP

- 42 emission factors and guidance were applied to unpaved road VMT values to estimate fugitive PM 10 emissions. 89 The AP

- 42 equation takes into account several factors including particle size , surface silt content, mean vehicle speed, surface moisture content, mean vehicle weight, the annual number of wet days, and the annual number of days.

Four categories of unpaved roads have been identified in Pinal County: agricultural, public, private, and trails. Each was determined to have different surface silt and moisture contents,
estimated from a Pinal County fiel d study conducted in June 2013. The four categories were additionally split into different classes of roads to account for varying ann ual average daily traffic (ADT) counts and estimated mean speeds ranging between 15 mph and 47 mph.

ADT is multiplied by total mil eage of each respective road to calculate daily VMT. The PM 10 emission factors were mu ltiplied by the VMT to produce unpaved road emissions for the PM 10 nonattainment area in 2008.

Unpaved exhaust emission rates were estimated as vehicle

- population

- weighted average exhaust emission rates for a given unpaved road’s estimated average speed bin. Rates were

extra cted for 2008 using results from the existing Pinal County configured MOVES results. 90

**b. Factoring growth between 2008 and 2018** 

Except for the unpaved public and private roads, the methods and travel activity employed in the 2008 calculation for the unpaved road emissions (unpaved Ag road, unpaved trails, and test
tracks ) were held constant for 2018. For u npaved public and private roads, ADTs were assumed

to experience growth equivalent to those reported for HPMS data from 2008 to 2013 and equivalent to popul ation projected growth between 2013 and 2018. 91 Additionally, numerous unpaved public road projects were completed or planned between 2008 and the end of 201 8

.

88 Id

. 89 AP

- 42 Section 13.2.2

90 See Appendix B (EI TSD) Section 5.1.4 for more information.

91 See Appendix B (EI TSD) Section 3.1.1.4 for more informa tion.

December 21, 2015 Final 57For exhaust emissions, emission rates were extracted for 2018 using results from the existing

P inal County configured MOVES results. 92



### 5.3.6 **Nonroad Emissions**

**a. Generally** 

With the exception of the locomotive and aircraft categories, all nonroad combustion emissions were calculated using Pinal County specific emissions from EPA’s NONROAD model. NONR OA D calc ulates emissions as a function of deterioration factors, horsepower, load factor, annual operating hours, and engine unit populations. 93

The NONROAD model calculates emissions from a varied assortment of equipment sources that are generally categorized. Th e model calculates emissions utilizing a “top down” approach . Its default equipment populations are based on national averages, which are then scaled down to represent smaller geographic areas (i.e., statewide and countywide) on the basis of human populati on and other statistics. 94

**b. Factoring growth between 2008 and 2018** 

Nonroad emissions were calculated for the 2018 calendar year scaling the 2018 equipment population by County population increases over the same period and assuming the emission rate per veh icle will stay constant over this period. 95



### 5.3.7 **Railroad Emissions**

**a. Generally** 

EPA summarized emissions factors for locomotives in a 2009 study. 96 The emission factors are used in calculating the annual railroad emissions by assuming two trains travel through the nonattainment area each hour, 366 days per year. 97

**b. Factoring growth between 2008 and 2018** 

ADEQ used a forecasted emission factor for locomotives from EPA’s 2009 study. 98 All other assumptions for calculating 2018 railroad emissio n, such as the railroad length and the number of trains per hour, are held the same as 2008.

92 Id

. 93 See Appendix B (EI TSD) Section 5.1.5 for more information.

94 See Appendix B (EI TSD) Section 3.1.1.5 for more information.

95 See Appendix B (EI TSD) Section 5.1.5 for more information

96 Emission Factors for Locomotives, EPA

- 420

- F

- 09

- 025, U. S. Environmental Protection, April 2009.

97 See Appendix B (EI TSD) Sections 3.1.1.7 and 5.1.6 for more information.

98 Emission Factors for Locomotives, supra note 96 at 8 (Table 6).

December 21, 2015 Final 58

### 5.3.8 **Construction Emissions**

**a. Generally** 

The location of construction activity and related fugitive dust emissions shifts from year to year.
The best source of informatio n for tracking activity within a specific domain and time period is dust control permits and respective types, acreage, and site location. PCAQCD staff 99 reviewed permits issued in late 2007 (4 th quarter) and selected those that were most likely to continue into 2008; these were then combined with permits issued in 2008 to create a shape file of polygons identifying the location and acreage of each of the issued permits. ADEQ calculated emission for each construction project by multiplying the number of acre s by an annual emission factor that varies by project type and by the average duration for a project type.

**b. Factoring growth between 2008 and 2018** 

The county recorded the number of permits issued in the Pinal County nonattainment area through 2013. The ratio of the number of dust permits issued in 2008 and 2013 was used to project construction emissions from 2008 to 2013. The ratio of projected count y population growth between 2013 and 2018 was used to project future construction permitting and ensuing
emissions from 2013 to 2018. 100 From 2013

- 2018, an economic improvement is accounted for by using the projected population growth factor.



### 5.3.9 **Emissions from Permitted**  **Stationary Sources** 

**a. Generally** 

PM 10 annual emissions (tons/yr) for each permitted stationary industrial /commercial facility in the nonattainment area were provided by the PCAQCD from permit files. PCAQCD permits
include estimates of PM 10 emissions for stationary sources only. PM 10 emissions from area sources such as unpaved road travel, livestock movement, and windblown dust were estimated separately and these separate methodologies are discussed in other sections.

**b. Factoring growth between 2008 and**  **2018**

The emission estimates calculated for the 2008 inventory were held constant for 2018.



### 5.3.10 **Fuel Combustion Sources**

Fuel combustion emissions were estimated for: ( 1) Fires

– including prescribed, wildfires, and agricultural field burning; ( 2) Residential Fuel Combustion

– from fuels including natural gas, oil, wood, and other; and ( 3) and O pen B urning

– including residential

, commercial and land clearing of debris. In the case where local permit data was available, this information was used

99 Email from Kate Edwards, Pinal County to Bob Dulla, Sierra Research, 2008 Construction Dust Permits, November 28, 2012.

100 See Appendix B (EI TSD) Sections 5.1.7 for more information.

December 21, 2015 Final 59for the estimation of combustion emissions in conjunction with EPA approved emission factors. In those instances where local permit data was not available ADEQ and PCAQCD allocated EPA
NEI estimates of combustion emissions. Emissions were held constant b etween 2008 and
2018. 101



### 5.3.11 **Unpaved Parking**

Unpaved parking emission estimates utilized a modified version of the methodologies presented in the 2008 Maricopa County PM 10 Emission Inventory for reentrainment. Emissions
were held constant from 2008 to 2018. 102



## 5.4 **C omparison**  **of Base Year Inventories to Control**  **Inventories**

Table 5

- 3 Comparing Base Year 2008 to Base Year 2018 to Post Control 2018 Inventories
ADEQ estimated the following
emissions reductions based on
2018 assumptions (e.g., that 30 miles of unpaved road controls are in place, implemented in 2016 and 2017). All reductions are presented in tons per year (TPY). Base 2008
Emissions Inventory

(TPY) Base 2018
Emissions Inventory

(TPY) Attainment
2018
Emissions
In ventory

(TPY) Post

contingency
2018
Emissions Inventory

(TPY)Windblown dust Developed Urban Lands 200.7 248.1 248.1 199.8
Developed Rural Lands (low density residential) 1959.7 1959.7 1959.7 1899.3

Unpaved Roads 4688.6 4653.0 3803.1 3793.8

Cleared Areas 398.1 457.0 457.0 325.8

Residential Construction 1302.4 837.5 837.5 430.5

Dairies 449.6 449.6 449.6 384.2

CAFOs 273.7 155.2 125.3 125.3

Desert Shrubland 38276.7 38276.7 38276.7 36719.3 Agriculture 19510.1 19510.1 7122.0 7122.0

Commercial Construction 686.4 441.4 441.4 216.3

Other 4243.9 4243.9 4243.9 4242.1 Site Development 858.7 552.2 552.2 278.9

Subtotal 72848.6 71784.4 58516.5 55737.3

101 See Appendix B (EI TSD) Sections 3.1.1.11 and 5.1.10 for more information.

102 See Appendix B (EI TSD) Sections 3.1.1.9 and 5.1.8 for more information.

December 21, 2015 Final 60Activity-based emissions Ag Fields

- Harvesting 312.9 312.9 207.1 207.1 Ag Fields

- Tilling 2540.3 2540.3 1658.0 1658.0

CAFOs 2614.3 1620.6 1369.2 1369.2

Paved Road 1180.7 1408.0 1408.0 1402.3 Unpaved Road 45127.8 45105.3 37186.4 36053.0

Fuel Combustion 28.3 34.9 34.9 34.9

Fires 19.9 22.2 22.2 22.2
Open Burning 13.6 16.8 16.8 16.8

Nonroad 121.3 144.4 144.4 144.4

Railroad 85.9 45.4 45.4 45.4

Construction 12955.3 8499.8 8499.8 4718.5
Dairy 186.6 184.0 184.0 148.2

Permitted Sources 781.3 781.3 781.3 781.3 Unpaved Parking 251.5 251.5 251.5 172.5

Subtotal 66219.7 60967.4 51809.0 46773.8

Total 139068.3 132751.8 110325.5 102511.1 Required contingency measures (equ al to 1 year of RFP out o f 3 total RFP years) = 22426.3

∙ 1⁄3

= 7475.4 TPY



## 5.5 **Motor Vehicle Emissions Budget (MVEB) Summary**

Transportation conformity is required by Secti on 176(c) of the CAA. Under EPA’s transportation conformity regulations, transportation plans and improvement programs must be consistent with, or conform to, the motor vehicle emissions budget (MVEB) defined in the applicable
SIP. 103 These budgets sp ecify the level of on

- road motor vehicle emissions that are consistent with attainment and maintenance of air quality standards and should include an adequate safety margin. 104

The budget considers the combined contributions of motor vehicles traveling roads within the nonattainment area, as well as the emissions from construction projects on those roads.
Emissions from non

- road vehicles are not included in the budget, nor are emissions produced by wind traveling over the roads and construction sites. Emissio ns from certain commercial roads, which are expected to remain fairly constant from one year to the next, are also omitted. The budget is established for annual emissions totals, and anticipates various changes in traffic, fleet characteristics, road work, and new rules and regulations up through calendar year 2018.

103 Conformity Criteria and Procedures: Motor vehicle Emissions Budget , 40 C.F.R. § 93.118 (2015).

104 Safety margin means the amount by which the total projected emissions from all sources of a given pollutant are less than the total emissions that would satisfy the applicable requirement for reasonable further progress, attainment, or maintenance. Conformity D efinitions , 40 C.F.R. § 93.101 (2015).

December 21, 2015 Final 61From the 2018 attainment inventory, ADEQ developed a comprehensive M VEB for the
nonattainment area. See the summary MVEB totals in Table 5

- 4 below.

Table 5

- 4 Annual MVEB by Source Sector

Source Tons of PM 10 Exhaust, tire

- , & brake

- wear 173.7 Unpaved road dust 105 2 6

, 433

. 5 Reentrained paved road dust 1,211.1
Road construction/maintenance 106 168.8

Total 2 7 , 987.1

The emissions total of 2 7

, 987.1 tons accounts for more than a quarter of the total attainment inventory; therefore, keeping motor vehicle emissions within this budget is critical to reach ing
attainment. The budget allows for a small safety margin of 81 tons.

Modeling indicates that the nonattainment area will not violate the 24

- hour PM10 national ambient air quality standard (NAAQS) as long as this budget is not exceeded, and as long as th e emissions are distributed appropriately, using planning tools such as hotspot analyses to prevent high concentrations of PM10 building up in a given place and time.

ADEQ has consulted Pinal County, Arizona Department of Transportation (ADOT) , and Marico pa Association of Governments (MAG) regarding the development of the MVEB for this West Pinal

PM 10 SIP. MAG is the designated metropolitan planning organization (MPO) for Maricopa County and portions of Pinal County, including the City of Apache Junction, the Town of Florence, the C ity of Maricopa , and some rural portions of Pinal County

. 107 MAG is responsible for preparing the Transportation Improvement Program (TIP) , Re gional Transportation Plan (RTP) , and the associated transportation conformity analyses for the above mentioned member agencies

. Since 2013, MAG has been conducting the interim emissions test conformity analyses
for both the West Pinal PM 10 and the West Ce ntral Pinal PM 2.5 nonattainment areas as portions of MAG member agencies are located within these areas.

The Sun Corridor MPO , established in 2013, provides transportation planning services to the communities of Casa Grande, Coolidge, Eloy and some rural portions of Pinal County

. 108 ADEQ also consulted with the Sun Corridor MPO regarding the MVEB in this West Pinal PM 10 SIP.
Some portions of the West Pinal PM 10 nonattainment area are located within MAG’s

105 The projected emissions totals for unpaved road dust and construction may be overestimates, since they do not consider the reductions that would be provided by control measures in upcoming Pinal County rules. This o mission
is intentional; the reductions from the upcoming rules are set aside as contingency measures to counterbalance unforeseen PM10 emissions growth. The additional controls from these rules are expected to increase the budget’s safety margin by over 1, 000 tons in 2018.

106 See note 105 above.

107 Designation of Areas of Air Quality Planning Purposes; State of Arizona, Pinal County PM 10 , 77 FR 32024, 32030 (May 5, 2 012) available at http://www.regulations.gov/#!documentDetail;D=EPA

- R09

- OAR

- 2010

- 0491

- 0063.

108 SunCorridor Metropolitan Planning Organization, Home, http://scmpo.org/ (last visited Sept. 2, 2015).

December 21, 2015 Final 62jurisdictional boundary, and because Sun Corridor is a new MPO, MAG has agreed to continue preparing the conformity analyses for the entire West Pinal PM 10 nonattainment area . It is for this reason that ADEQ primarily consulted with MAG and ADOT to review this MVEB

. Subject to EPA’s approval and finding of adequacy, the MVEB in this West Pinal PM 10 SIP will be used in future conformity analyses.

For m ore details regarding MVEB calculations and the relationship between the annual emissions inventory, modeling, and the conformity budget, see Appendix D (Atta inment TSD ),
Section D4

.

December 21, 2015 Final 63

## 6 **CONTROL MEASURES**

The Clean Air Act section 172(c)(1) requires that “[nonattainment plan] provisions shall provide for the implementation of all reason ably available control measures as expeditiously as practicable...and shall provi de for attainment of the national primary ambient air quality standards.” In reviewing a statute, regulation or rule for SIP approval, EPA looks to ensure that the provision is enforceable as required by CAA section 110(a) and is consistent with all appli cable EPA guidance.

CAA section 172(c)(9) requires that the 189(a) plan provide for the implementation of contingency measures , which are to be undertaken if the area fails to make RFP or to attain the

PM

- 10 standard as projected in the plan. S uch measures shall take effect without further
action , such as public hearings or legislative review, by the state or EPA. EPA has interpreted section 172(c)(9) to allow states to implement contingency measures before they are triggered by a failure of RFP or attainm ent as long as those measures are intended to achieve reductions over and beyond those relied on in the attainment and RFP demonstrations. 109 The CAA does not specify how many contingency measures are necessary nor does it specify the level of
emission reduc tions they must produce.

ADEQ believes that the submitted (or soon to be submitted) control measures qualify as reasonably available control measures (RACM). For a full RACM discussion, see Appendix F. ADEQ has also projected attainment by the required date, which is the end of December 2018, and the efficacy of chosen contingency measures to ensure RFP past the attainment date. The contingency measures will take effect presently to avoid any necessary future further action by
the state or the EPA. Pina l County’s general fugitive and construction rules are now final rules

, effective in January 2016

. ADEQ’s and Pinal County’s chosen control measures to meet attainment and contingency measure requirements are described below.



## 6.1 **Agricultural Rule**

**– Attainme**  **nt and Contingency in Part**

**6.1.1 Commercial Farms Summary**  **(R18**

**- 2** 

**- 610 and** 

**- 610.03)** 

The commercial farms rule was credited towards attainment. The rule requires new controls for commercial farmers in the Pinal County PM Nonattainment Area, as defined in R18

- 2

- 610 (37). Commercial farmers in that area are required to implement one Best Management Practice ( BMP ) every day of the year from the tillage, ground operations and harve st, commercial farm roads, noncropland, and significant earth moving categories, and two BMPs

109 See Proposed Approval of Maricopa County Serious Nonattai nment Area Plan, 75 FR 54806, 54815 (Sept. 9, 2010). See generally

, LEAN v. EPA, 382 F.3d 575 (5th Cir. 2004). See also General Preamble for the Implementation
of Title I of the Clean Air Act Amendments of 1990 , 57 Fed. Reg. 13,498, at 13512.

December 21, 2015 Final 64from the cropland category. On the day before and during a day (or, depending on the BMP, just the day) forecast to be high risk for dust generation, as determine d by the dust control forecast (R18

- 2

- 610 (18)), a commercial farmer is required to ensure implementation of one BMP that is in the high risk category for tillage, ground operations and harvest, cropland, commercial farm roads, and noncropland. If a commer cial farmer implements conservation tillage or a reduced tillage system for the tillage category on a crop, he /she does not have to implement a BMP for ground operations

, harvest

, or cropland for that crop acreage, whether or not a day is forecasted to be high risk.



### 6.1.2 **Appendix 2**

**– Test Method for**  **Silt Loading**

Appendix 2 is also submitted into the Arizona SIP. It will be used to determine compliance with sections requiring the use of a silt test method in the commercial farms rule.



### 6.1.3 **Commercial Animal Operation s Summary**  **(R18**

**- 2** 

**- 611 and** 

**- 611.03)** 

Generally, the animal operations rules are credited towards attainment , except for thos e animal operations not yet existing in the nonattainment area (e.g. poultry and swine operations) . However, t he section applicable to commercial dairy operations was credited toward contingency measures

,

The rule requires new controls for commercial animal operators in the Pinal County PM
Nonattainment Area defined in R18

- 2

- 611(1)(i). Commercial animal operators are required to implement one BMP every day of the year from the arenas, corrals and pens, animal waste (and feed) handling and transporting, unpaved access connections and unpaved roads or feed lanes categories. For beef cattle feedlots, in addition to selecting one BMP from each category, on the day that is forecast to be high risk for dust generation, as determined by the dust control forecast, must add water to pen surface, as defined in R18

- 2

- 611(3)(a).

For commercial dairy operation, in addition to selecting one BMP from eac h category, on the day that is forecast to be high risk for dust generation, as determined by the dust control forecast, must apply and maintain one of the four following BMPs on unpaved roads that experience more than 20 VDT from 2 or more axle vehicles:

1. Apply and maintain pavement in high traffic areas,

2. Apply and maintain aggregate cover,

3. Apply and maintain synthetic particulate suppressant, or

4. Apply and maintain water as a dust suppressant.

December 21, 2015 Final 65

### 6.1.4 **Irrigation Districts in the Pinal County PM Nona ttainment Area**  **(R18**

**- 2** 

**- 612 and** 

**- 612.01)** 

Rule R18

- 2

- 612 was renumbered and rule R18

- 2

- 612.01 was added in order to provide definitions and BMPs for irrigation districts only within the Pinal County PM Nonattainment area. Senate Bill 1408 (Forty

- ninth Legisla ture, Second Regular Session, 2010, Chapter 82, § 1) adds the activities of irrigation districts in regulated areas established after June 1, 2009. This rule adds requirements for irrigation districts to implement one BMP from the unpaved operation and mai ntenance roads, canals, and unpaved utility access roads categories. No credit was taken for access road provisions , but attainment credit was taken for operation and maintenance irrigation roads

.



### 6.1.5 **Implementation Schedule**

**– Agricultural Rules** 

The Arizona A dministrative Code Agricultural Rules were effective upon filing with the Arizona Secretary of State, as of July 2, 2015.

The rules must be complied with beginning January 1, 2016. The rules mandate that by December 31, 2015, agricultural sources engaged in regulated agricultural activity must complete a BMP Program General Permit Record Form, and must complete such form ev ery year thereafter by March 31.



### 6.1.6 **Enforceability**

**6.1.6.1 Commercial Farms** 

6.1.6.1.1 Authority

The Agricultural BMP Committee has the statutory authority to adopt the Agricultural BMP
commercial farm r ules under A.R.S. § 49

- 457(H). Under A.R.S. §§ 49

- 457(I), (J), and (K), AD EQ has the statutory authority to enforce a regulated person’s compliance with the rul es and general permit program. ADEQ has additional enforcement authority under A.R.S. §§ 49

- 460,

- 461,

- 462,

- 463, and

- 464, which ADEQ will resort to if measures taken u nder A.R.S. §§ 49

- 457(I), (J), and (K) are unsuccessful to return a facility to compliance.

6.1.6.1.2 Applicability

The crop operations rules apply to commercial farmers who engage in regulated agricultural activity in the Pinal County PM Nonattainment Area. A comm ercial farmer is an individual, entity, or joint operation in general control of more than 10 or more contiguous acres of land used for agricultural purposes. “Regulated activity” upon such farms would be those activities or sources statutorily defined in A.R.S. § 49

- 457(P), consisting of tilling, harvesting (including ground operations), and those areas of a commercial farm that are not normally in crop production (such as commercial farm roads and noncropland as defined in the submitted rule),
those areas that are normally in crop production including prior to plan emergence and when

December 21, 2015 Final 66the land is not in crop production (covering cropland as defined in the submitted rule), and earthmoving activities.

6.1.6.1.3 Exemptions

Exemptions from the rule’s requirements only ap ply to farmers who choose to implement conservation tillage or reduced tillage system BMPs for the tillage category. If farmers choose either of these BMPs for the tillage category, they do not have to implement BMPs for ground operations and harvest on e ither a regular or high risk day, nor would they have to implement BMPs on cropland on either a regular or a high risk day. These exemptions exist because both BMPs, conservation tillage and reduced tillage systems , have control efficiencies which temporal ly affect other regulated activities or sources during multiple planting phases. Both BMPs can provide adequate control against tillage emissions and either leave plant stubble protruding from the ground or leave plant material laying on the field's surfa ce, providing control of windblown dust year

- round.

6.1.6.1.4 Alternative Practices

A farmer may develop different practices to choose as BMPs to control PM emissions, but such practices will not be effective until they are submitted as a SIP revision to the EPA per A.R.S. §
49

- 457(L). Additionally, as provided by A.A.C. R18

- 2

- 610.03(E), any alternative practices must be “proven effective through on

- operation demonstration trials to the Committee.” The already statutorily stated purpose of BMPs is to reduce PM 10 emis sions. 110 Therefore, before submittal, these alternative practices would be thoroughly evaluated on a case

- by

- case basis by the Agricultural BMP Committee, and ADEQ would provide technical input as needed, and any other advice, as needed, to ensure the newl y developed practice is sufficiently effective to
control PM10.

6.1.6.1.5 Notice

The definitions and rule requirements are sufficiently clear so as to put the regulated public on notice. Where needed, many definitions rely on specific test methods and are extremely detailed. ADEQ and the Agricultural BMP have worked together to ensure that the rule is clear
and understandable. The West Pinal County applicable commercial farms rule is more comprehensive and specific than the previou s Maricopa rule , which has been in place for several years , in its current and modified form s

. 111

As far as outreach is concerned, the Agricultural BMP statute that establishes the Agricultural BMP Committee requires the Committee to develop and commence an education program. 112 The Agricu ltural BMP Committee has been working fervently to develop a program for the Pinal nonattainment area community. The outreach developed thus far is very thorough and

110 A.R.S. § 49

- 457(H) (2015).

111 See generally , Approval and Promulgation of Maricopa PM

- 10 Arizona Implementation Plan, 66 FR 51869 (Oct. 11, 2001).

112 A.R.S. § 49

- 457(M) (2015).

December 21, 2015 Final 67informative. The Committee has created a guidebook, specific to this rule, to help the reg ulated public understand the new standards. There will be information disseminated, also, explaining how to sign up for the high risk forecast, which is critical to the rule’s effectiveness and penetration. The Committee intends to supply these extensive i nformational guidebooks at several outreach meetings over the course of the months between October 2015 and January 2016, to ensure compliance with the rule by the compliance date. The meetings will be held
within the nonattainment area where the Committee will explain the importance of complying with the rule. Additionally, the Committee, ADEQ, and the Department of Agriculture are working diligently to develop a comprehensive 3

- year survey as required by the rule.

6.1.6.1.6 Compliance Schedule

As previously state d, per the Agricultural BMP statute as revised, A.R.S. § 49

- 457, “[a] person who commences a regulated agricultural activity shall immediately comply with the agricultural general permit [prescribed by the statute].” Immediate compliance, in this case, wou ld be after December 31, 2015, beginning January 1, 2016, as required by the commercial farm rule.

6.1.6.1.7 Records

A General Permit Record Form must be filled out and kept as a record onsite and made available for review within two business days of notice. The re quirements for the record form
are listed in A.A.C. R18

- 2

- 610.03(C), and shall include notation, of the categorical best management practices a farmer has chosen to apply a regulation basis and on high risk days, as applicable. Such form shall also include a notation of any changes. The purpose of the record form is to assist inspectors with enforcement and to hold facilities accountable for their BMPs
chosen.

Beginning January 1, 2016, a commercial farmer must maintain records demonstrating compliance wit h the rules for three years, including a copy of the BMP Program General Permit Record Form. Additionally, by January 31, 2018, farmers must submit their first BMP 3

- Year Survey which reflects the BMPs chosen in the previous calendar year. The next due da te after January 31, 2018, will be January 31, 2021 (reporting on 2020), and every three years thereafter. The required information is listed in A.A.C. R18

- 2

- 610.03(D), and will ensure that facilities are held accountable for the required BMPs and will als o provide ADEQ with the

necessary information for future emissions calculations.

6.1.6.1.8 Test Methods and Compliance

Compliance is determined by inspection and records review. ADEQ will enforce the rule as necessary and as authorized, but its primary goal will be to ensure ADEQ takes advantage of every opportunity to provide compliance assistance to prevent any violations. Preventing violations is the most effective form of protection of human health and the environment. The agricultural community is very close

- k nit in Arizona and has complex needs. Inspectors are linked by cell phone to instant monitor alerts, even in the middle of the night. ADEQ’s compliance section is extremely responsive to such alerts and any complaints. ADEQ responds
to such alerts and com plaints with contact and/or an inspection of the problem area, in

December 21, 2015 Final 68addition to regular monthly inspections of various agricultural facilities according to internal goals.

Test methods include those listed in Table 6

- 1 below.

Table 6

- 1 Commercial Farms Rule Test Methods

Test Method Location in the rule and purpose

NRCS Practice Code 609, Surface Roughening, amended through November 2008. R18

- 2

- 610 (53), in the definition of “surface roughening,” to ensure the soil surface is manipulated to produce clods on the land surface, if implementing the BMP on cropland

NRCS National Agronomy Manual, Subpart 503.51, E stimating Crop Residue Cover, amended through February 2011. R18

- 2

- 610 (14), in the definition of “cover crop,” to ensure the vegetation meets the minimum ground cover requirement of 60%, if implementing the BMP on cropland

R18

- 2

- 610 (15), in the definiti on of “critical area planting,” to ensure 60% required ground cover if implementing the BMP on noncropland

R18

- 2

- 610 (36), in the definition of “permanent cover,” to ensure perennial species are used to meet minimum requirements of 60% ground cover if imp lementing the BMP on cropland

R18

- 2

- 610 (47), in the definition for “residue management,” to ensure a minimum of 60% ground cover of crop or other plant residues between harvest and tillage, if choosing the BMP to control cropland

NRCS Estimating Soil Moisture by Feel and Appearance Method, amended through April
1998. R18

- 2

- 610 (39), in the definition of “planting based on soil moisture,” to ensure the appropriate amount of moisture to germinate seeds prior to planting, implementing the BMP for tillage

R18

- 2

- 610 (56), in the definition for “tillage based on soil moisture,” to ensure fields have the minimum required soil moisture content from irrigation or precipitation prior to soil disturbance, If implementing the BMP for tillage

R18

- 2

- 610.03 (B )(6), as the method for determining appropriate soil moisture for the applicable earthmoving activity BMPs NRCS Conservation Practice Standard, Code 380, Windbreak/Shelterbelt Establishment, amended R18

- 2

- 610 (65), in the definition for “wind barrier,” to ensure a vegetative wind barrier is sufficiently

December 21, 2015 Final 69Test Method Location in the rule and purpose through August 21, 2009 sufficient to change the pattern of air flow over the land surface to control PM emissions, if choosing this BMP for noncropland, commercial farm road s (high risk days), or cropland

Silt Content Test Method Appendix 2, Subsection (N), incorporated into R18

- 2

- 610 (51),

**6.1.6.2 CAFOs** 

6.1.6.2.1 Authority

The Agricultural BMP Committee has the statutory authority to adopt the Agricultural BMP crops rules under A.R.S. § 49

- 457(H). Under A.R.S. §§ 49

- 457(I), (J), and (K), ADEQ has the statutory authority to enforce a regulated person’s compliance with the rules and general permit program. ADEQ has additional enforcement authority under A.R.S. §§ 49

- 460,

- 461,

- 462,

- 463, a nd

- 464, which ADEQ will resort to if measures taken under A.R.S. §§ 49

- 457(I), (J), and (K) are unsuccessful to return a facility to compliance.

6.1.6.2.2 Rule Applicability

The animal operations rules apply to commercial animal operators who engage in regulated agricultural activity in the Pinal County PM Nonattainment Area. A commercial farmer is an individual, entity, or joint operation in general control of a :

1. commercial dairy operation with more than 150 dairy cattle with the nonattainment boundary

, 2. commerci al beef feedlot with more than 500 beef cattle within the nonattainment boundary

, 3. commercial poultry facility with more than 25,000 egg laying hens within the
nonattainment area , and/or

4. commercial swine facility with more than 50 animal units for more th an 30 consecutive days within the nonattainment area

. “Regulated activity” upon such operations would be those activities or sources statutorily defined in A.R.S. § 49

- 457(P), consisting of earthmoving activities and one of the categorical CAFO practices related to: unpaved access connections, unpaved roads or feed lanes, animal waste handling and transporting, arenas, corrals, and pens.

6.1.6.2.3 Exemptions or Additional Requirements

Those operations or operator exempted from this rule are those that fall outside of the applicable animal population thresholds listed above. There are more specific requirements, however, for some animal operations on high risk days. On a high risk day, commercial dairy operations within Pinal County shall apply and maintain one of th e listed BMPs on unpaved roads that experience more than 20 vehicle trips per day from two or more axle vehicles. Beef feedlots must also add three to six gallons of water per head of cattle per day to cattle occupied pen surfaces.

December 21, 2015 Final 706.1.6.2.4 Alternative Practices

A n operator may develop different practices to choose as BMPs to control PM emissions, but such practices will not be effective until they are submitted as a SIP revision to the EPA per A.R.S. § 49

- 457(L). As provided by A.A.C. R18

- 2

- 611.03(K), any alterna tive practices must be “proven effective through on

- operation demonstration trials to the Committee.” The already statutorily stated purpose of BMPs is to reduce PM 10 emissions. Therefore, before submittal,

any alternative practices would be thoroughly evaluated on a case

- by

- case basis by the Agricultural BMP Committee, and ADEQ would provide technical input and any other advice, as needed, to ensure the newly developed practice is sufficiently effective to cont rol PM 10 .

6.1.6.2.5 Notice

The definitions and rule requirements are sufficiently clear so as to put the regulated public on notice. Where needed, many definitions rely on specific test methods and are extremely detailed. ADEQ and the Agricultural BMP Committee ha ve worked together to ensure that the
rule is clear and understandable. The West Pinal County applicable commercial farms rule is more comprehensive and specific than the previous Maricopa rule, which has been in place for several years in its current and modified forms

. 113

As far as outreach is concerned, the Agricultural BMP statute that establishes the Agricultural BMP Committee requires the Committee to develop and commence an education program. 114 The Agricultural BMP Committee has been working fervently to develop a program for the Pinal nonattainment area community. The outreach developed thus far is very thorough and informative. The Committee has created a guidebook, specific to this rule, to help the regulated public understand the new standards. Th ere will likely be information in the guidebook, also, explaining how to sign up for the high risk forecast, which is critical to the rule’s effectiveness. The Committee intends to supply these extensive informational guidebooks to the regulated public to ensure compliance with the rule by the compliance date. Additionally, the Committee, ADEQ, and the Department of Agriculture have been working to develop a comprehensive 3

- year survey for each animal operations type, as required by the
rule.

6.1.6.2.6 Compliance Schedule

As previously stated, per the Agricultural BMP statute as revised, A.R.S. § 49

- 457, “[a] person who commences a regulated agricultural activity shall immediately comply with the agricultural general permit [prescribed by the statute].” Immediate compliance, in this case, would be after December 31, 2015, beginning January 1, 2016, as required by the animal operations rule.

113 See generally , Approval and Promulgation of Maricopa PM

- 10 Arizona Implementation Plan, 66 FR 51869 (Oct. 11, 2001).

114 A.R.S. § 49

- 457(M) (2015).

December 21, 2015 Final 716.1.6.2.7 Records

A General Permit Record Form must be filled out and kept as a record onsite and made
available for review within two business days of notice. The requirements for the record form
are listed in A.A.C. R18

- 2

- 61 1 .03(H ), and shall include notation of the categorical BMPs an animal operator has chosen to apply on a regular basis and on high risk days , as applicable

. Such for m shall also include a notation of any changes. The purpose of the record form is to assist inspectors with enforcement and to hold facilities accountable for their BMPs chosen.

Beginning in January 1, 2016, a commercial animal operator must maintain reco rds demonstrating compliance with the rules for three years

, including a copy of the BMP Program General Permit Record Form. Additionally, by January 31, 2018, operators must submit their
first BMP 3

- Year Survey which reflects the BMPs chosen in the previo us calendar year. The next due date after January 31, 2018, will be January 31, 2021 (reporting on 2020), and every three years thereafter. The required information is listed in A.A.C. R18

- 2

- 61 1.03(I ), and will ensure
that facilities are held accountable for the required BMPs and will ensure that facilities are held accountable for the required BMPs and will also provide ADEQ with the necessary information
for future emissions calculations.

6.1.6.2.8 Test methods and Compliance

Compliance is determined by inspection and records review. ADEQ will enforce the rule as necessary and as authorized, but its primary goal will be to ensure ADEQ takes advantage of every opportunity to provide compliance assistance to prevent any violations. Preventing violations i s the most effective form of protection of human health and the environment. The agricultural community is very close

- knit in Arizona and has complex needs. Inspectors are linked by cell phone to instant monitor alerts, even in the middle of the night. AD EQ’s compliance section is extremely responsive to such alerts and any complaints. ADEQ responds to such alerts and complaints with contact and/or an inspection of the problem area, in addition to regular monthly inspections of various agricultural facilit ies according to internal goals.

Test methods are listed in Table 6

- 2 below.

Table 6

- 2 CAFO Rule Test Methods

Test Method Location in the rule and purpose

NRCS Conservation Practice Standard, Code 380, Windbreak/Shelterbelt Establishment, amended through August 21, 2009 R18

- 2

- 611 (2)(x) or (3)(r)

, the equivalent
definition s for “wind barri er,” to ensure a vegetative wind barrier is sufficiently sufficient to change the pattern of air flow over the land
surface to control PM emissions , if choosing this
BMP for control of arenas, corrals, and pens, at a dairy operation of a commercial beef lo t control, or to control unpaved roads or feed lanes at swine operations,

December 21, 2015 Final 72**6.1.6.3 Irrigation Districts** 

6.1.6.3.1 Authority

The Agricultural BMP Committee has the statutory authority to adopt the Agricultural BMP crops rules under A.R.S. § 49

- 457(H). Under A.R.S. §§ 49

- 457(I), (J), and (K), ADEQ has the statutory authority to enforce a regulated person’s compliance with the ru les and general permit program. ADEQ has additional enforcement authority under A.R.S. §§ 49

- 460,

- 461,

- 462,

- 463, and

- 464, which ADEQ will resort to if measures taken under A.R.S. §§ 49

- 457(I), (J), and (K) are unsuccessful to return a facility to comp liance.

6.1.6.3.2 Rule Applicability

The irrigation district rules apply to irrigation districts within a PM Nonattainment Area designated after June 1, 2009 (including the West Pinal Nonattainment area), that engage in regulated agricultural activity in the Pinal County PM Nonattainment Area. An irrigation district is a political subdivision governed by A.R.S. Title 48, Chapter 19, Irrigation and Water Conservation Districts, and per A.R.S. § 48

- 2901, all such subdivisions are declared municipal corporations for al l purposes.

“Regulated activity” by such districts would be regulating those activities or impact of sources as statutorily defined in A.R.S. § 49

- 457(P), which are only under the jurisdiction and control of the district, including regulating practices rel ated to unpaved operation and maintenance roads, canals, and unpaved utility access roads.

6.1.6.3.3 Exemptions or Additional Requirements

Those operations or operator exempted from this rule are those that fall outside of the applicable requirements, including jur isdiction, listed above. There are no additional requirements on high risk days.

6.1.6.3.4 Alternative Practices

A district may develop different practices to choose as BMPs to control PM emissions, but such practices will not be effective until they are submitted a s a SIP revision to the EPA per A.R.S. §
49

- 457(L). As provided by A.A.C. R18

- 2

- 612.01(E), any alternative practices must be “proven effective through on

- operation demonstration trials to the Committee.” The already statutorily stated purpose of BMPs is to reduce PM

- 10 emissions. Therefore, before submittal, any alternative practices would be thoroughly evaluated on a case

- by

- case basis by the Agricultural BMP Committee, and ADEQ would provide technical input and any other advice, as needed, to
ensure the n ewly developed practice is sufficiently effective to control PM10.

6.1.6.3.5 Notice

The definitions and rule requirements are sufficiently clear so as to put the regulated public on notice. Where needed, many definitions rely on specific test methods and are extrem ely

December 21, 2015 Final 73detailed. ADEQ and the Agricultural BMP have worked together to ensure that the rule is clear
and understandable.

6.1.6.3.6 Compliance Schedule

As previously stated, per the Agricultural BMP statute as revised, A.R.S. § 49

- 457, “[a] person who commences a reg ulated agricultural activity shall immediately comply with the agricultural general permit [prescribed by the statute].” Immediate compliance, in this case, would be after December 31, 2015, beginning January 1, 2016, as required by the irrigation district s rule.

6.1.6.3.7 Records

A General Permit Record Form must be filled out and kept as a record onsite and made available for review within two business days of notice. The requirements for the record form
are listed in A.A.C. R18

- 2

- 611.03(H), and shall include not ation of the categorical BMPs an irrigation district has chosen to apply on a regular basis. Such form shall also include a notation of any changes. The purpose of the record form is to assist inspectors with enforcement and to
hold facilities accountable for their BMPs chosen.

Beginning January 1, 2016, an irrigation district must maintain records demonstrating compliance with the rules for three years, including a copy of the BMP Program General Permit Record Form. Additionally, by January 31, 2018, dist ricts must submit their first BMP 3

- Year Survey which reflects the BMPs chosen in the previous calendar year. The next due date after January 31, 2018, will be January 31, 2021 (reporting on 2020), and every three years thereafter. The required informatio n is listed in A.A.C. R18

- 2

- 611.03(I), and will ensure that districts are held accountable for the required BMPs and will also provide ADEQ with the necessary information for future emissions calculations.

6.1.6.3.8 Test methods and Compliance

Compliance is determin ed by inspection and records review. ADEQ will enforce the rule as necessary and as authorized, but its primary goal will be to ensure ADEQ takes advantage of every opportunity to provide compliance assistance to prevent any violations. Preventing violatio ns is the most effective form of protection of human health and the environment. The agricultural community is very close

- knit in Arizona and has complex needs. Inspectors are linked by cell phone to instant monitor alerts, even in the middle of the night . ADEQ’s compliance section is extremely responsive to such alerts and any complaints. ADEQ responds to such alerts and complaints with contact and/or an inspection of the problem area, in addition to regular monthly inspections of various agricultural fac ilities according to internal goals.

Applicable test methods are listed in Table 6

- 3 below.

Table 6

- 3 I rrigation Districts Rule Test Methods

Test Method Location in the rule and purpose NRCS Conservation Practice Standard, Code 380, Windbreak/Shelterbelt Establishment, amended R18

- 2

- 612 (33), in the definition for “wind barrier,” to ensure that the vegetative barrier is

December 21, 2015 Final 74through August 21, 2009 sufficient to change the pattern of air flow over
the land surface to control PM emissions

December 21, 2015 Final 75

### 6.1.7 **Credited Annual Emission Reductions from Agricultural BMP Rules** 

Table 6

- 4 A gricultural Best Management Practices Rule Reductions (Attainment and Contingency)

Attainment Contingency AgBMP Rule
Subtotal Unpaved

crop farm
roads Unpaved
canal
O&M
roads Harvesting and Tilling CAFOs DairiesWindblown dust Unpaved Roads 70 5 .2 144.7 849 .9

Dairies (including unpaved roads) 65.4 65.4

CAFOs (including unpaved roads) 29.9 29.9

Agriculture 12

, 388.1 12

, 388.1
Subtotal 705 .2 144.7 12

, 388.1 29.9 65.4 13

, 33 3 .3Activity-based emissions Ag Fields

- Harvesting 105.8 105.8

Ag Fields

- Tilling 882.3 882.3

CAFOs 251.4 251.4 Unpaved Road 7

, 341.3 577.6 7

, 918.8 Dairy 35.8 35.8
Subtotal 7

, 341. 3 577.6 988.1 251.4 35.8 9

, 194. 2
Total 8

, 046.5 722.3 13

, 376.2 281.3 101.2 22

, 527

. 5

December 21, 2015 Final 76

## 6.2 **Fugitive dust**

**– Contingency Measure** 

**6.2.1 Fugitive Dust Rule Summary** 

This rule is a general area source control rule, not permit based. Owners and/or operators of several source types are subject to implement required PM10 control measures on applicable

sources to meet visible emissions and stabilization requirements , in order to reduce PM emissions in the West Pinal Nonattainment Area. Open areas/vacant lots of a particular threshold must be stabilized to 20% opacity for fugitive emissions on the property, and owners/operators must install and maintain trespassing signs or physical barriers if trespass occurs on the property. Within 30 days following the discovery of the threshold disturbed surface area, the owner/operat or shall sign up to receive ADEQ’s Pinal County Dust Control Forecast (i.e. high risk forecast) and shall ensure the lot is stabilized the day leading up to and the day of high risk forecast. Unpaved lots of a particular size threshold must be controlled to meet opacity and stabilization re quirements. Unpaved roads above 150 Average Daily Trips (ADT) are subject to specific opacity and stabilization (silt loading/content) standards, and owners/operators must incrementally control a specific length of such unpaved roads. Paved public roadwa ys are subject to trackout clean up and taking stabilization actions before, during and after work on unpaved road shoulders along paved public roadways.



### 6.2.2 **Planned Rule Implementation Schedule**

**– General Fugitive Dust**  **Rule**

The Pinal County Air Quality Control District filed the rule with the Secretary of State . T he rule

was published in the Arizona Administrative Register as a final rule, effective January 1, 2016. 115 The hearing/Board of Supervisors meeting took place on October 28, 2015. Pinal County provided ADEQ with its rule making documentation to submit to the EPA. 116



### 6.2.3 **Enforceability**

**6.2.3.1 Authority** 

Per A.R.S. 49

- 479(A), the Pinal County Board of Supervisors has specific authority, subject to procedural requirements, to adopt and implement rules to control the atm ospheric release of air contaminants originating within the Pinal County territorial limits. Pinal County may adopt rules that are more stringent than ADEQ’s as long as certain conditions are met such as the rule is necessary to address a peculiar local condition and there is credible evidence that the rule is either: (1) necessary to prevent significant threat to public health or the environment and the rule is technically and economically feasible, or (2) the rule is required under federal statute or

re gulation. ADEQ has no similar construction permit, therefore the permit and authorizing rule

115 See Appendix I ; s ee also Exhibit G

- VIII.

116 See Appendix I

.

December 21, 2015 Final 77are more stringent than ADEQ’s rules. However, this rule is federally required per C.A.A. §189, insofar as to ensure that ADEQ is able to submit a SIP on behalf of Pinal County for the West Pinal County moderate nonattainment area, and that there are rules in place to control PM emissions for a significant dust generating source s of general fugitive dust, particularly unpaved
roads.

Per A.R.S. 49

- 473, the Board of Supervisors additionally has authority to authorize Pinal County Air Quality District to carry out the necessary investigations, inspections, and enforcement of any rules adopted pursuant to prevailing statutory authority. Such prevailing statutory
authori ty includes those defining violations and processes for violation consequences, such as A.R.S. §§ 49

- 502,

- 510,

- 511,

- 513, and

- 514.

**6.2.3.2 Rule Applicability** 

The Fugitive Dust rule applies to owners/or operators of dust emitting sources such as open areas/vacan t lots , unpaved roads, unpaved lots, and paved public roadways to control PM
emissions from such sources located within the West Pinal Nonattainment Area and activities upon such sources. Regulated sources requiring control measures are those above applica ble
thresholds as follows:

1. open areas, public or private, of 1.0 acre or larger that have 0.5 acres or more of
disturbed surface area
2. unpaved lots 5,000 ft 2 or larger in size
3. unpaved public roads with 150 Average Daily Trips (ADT)

4. paved public roadways wit h trackout that extends 50 feet or more

5. paved public roadway shoulders

**6.2.3.3 Exemptions or Additional Requirements** 

Anything below the threshold s listed above is not subject to stabilization or control requirements under this rule

.

**6.2.3.4 Alternative Practices** 

Alternati ve measures that are adequate to address a work site’s applicable standards in PCAQCD Code § 4

- 3

- 180 must be approved by PCAQCD and the EPA Administrator.

**6.2.3.5 Notice** 

The definitions and rule requirements are sufficiently clear so as to put the regulated public on notice. Pinal County has worked closely with industry representatives to ensure the rule is
understandable and clear so that the regulated can comply with it. Regulated government entities (owners/operators of several public roads) , Pinal County, and A DEQ have consulted
with on e another to ensure understanding of the rule as written. Pinal County and ADEQ also intend to conduct outreach to ensure the regulated public is informed of the rule

, its requirements

, and how to sign up for the high risk forecast. Where needed, the rule relies on specific test methods to ensure compliance.

December 21, 2015 Final 78**6.2.3.6 Compliance Schedule** 

P er the language of the rule

, it will be effective as of January 1, 2016

. From that point on, the regulated co mmunity must comply with the rule.

**6.2.3.7 Records** 

Any person subject to the Fugitive Dust rule shall compile and retain records that provide evidence of control application. Upon notice, such person shall provide the records and supporting documentation as so on as possible but no later than 48 hours to Pinal County. Additionally, each city, county, or state agency with primary responsibility for existing paved public roadways and unpaved roads shall provide the Pinal County with a list of all unpaved roads, in cluding data of the length of and ADT on, unpaved roadways in its jurisdiction by January 30th of each year. Additionally, by January 30 of each year, each entity as previously described shall submit to the District a list of unpaved roads paved within th e previous year, along with their respective ADTs and mileage. Copies of records and reporting shall be retained for at least two years.

**6.2.3.8 Test methods and Compliance** 

Compliance is determined by inspection and records review. Failure by any person to comply with the requirements of the rule is a violation and such person is subject to Pinal County’s authority to enforce, as listed above. In particular, in the case that any owner and/or operator of unpaved roads with ADT greater than 150 do not comply with ap plicable requirements, including paving, applying dust suppressants other than water, or applying gravel on 15 miles of roads above 150 ADT (or the equivalent from 2019 and beyond), each owner/operator shall be subject to enforcement. All owners/operators shall be held jointly and severally liable, regardless of the efforts made by one entity over others. For example, if Entity A paves 14 miles in one year, but none of the other owners/operators apply (and maintain

, if necessary) any of
the listed control m easures for the same year, then all owners/operators, including Entity A, are subject to enforcement . All parties in that case would be held responsible for the road control deficiency violation. It is up to all the owners/operators within the West Pinal N onattainment area to demonstrate compliance with this rule.

As a practical matter, the stabilization of unpaved roads in the West Pinal PM10 Nonattainment Area is coordinated between several entities including Pinal County Public Works; the Sun
Corridor MP O and member cities and towns including Casa Grande, Eloy, Coolidge, and Pinal County; Maricopa Association of Governments and member city and towns including Maricopa and Queen Creek, and Pinal County. Coordination efforts are achieved through regular MP O meetings, development of transportation improvement plans (TIP’s) incorporating additional stabilization requirements, and interagency coordination with respect to planning and budgetary needs.

Applicable test methods are listed in Table 6

- 5 below.

December 21, 2015 Final 79Table 6

- 5 General Fugitive Dust Rule Test Methods

Test Method Location in the rule and purpose

Opacity (as applicable from PCAQCD code §4

- 9

- 340) § 4

- 1

- 130.2.A

, and 3.A.i, 4.A.i, and 5.A.i.ii, in the control requirements for measuring fugitive dust
from the applicable open areas/vacant lots

, unpaved lots, unpaved roads, and paved public roads, respectively, by m eas uring and ensuring opacity is below 20%

Visible Crust Determination [The Drop Ball Test] as defined in PCAQCD Code § 4

- 9

- 329.B.1 § 4

- 1

- 130.2.F.i, to ensure control measures implemented ensure surface crusting is resistant
to wind

- driven fugitive dust

Threshold Friction Velocity as determined by
test method in P CAQCD C od e § 4

- 9

- 320.B.2 § 4

- 1

- 130.2.F.ii , to determine the threshold friction velocity of disturbed surface areas that are not crusted or vegetated

NRCS Conservation Practice Standard, Code 380, Windbreak/Shelterbelt Establishment, amended through August 21, 2009 Determination of Flat Vegetative Cover, PCAQCD Code §4

- 9

- 320.B.3 R18

- § 4

- 1

- 130.2

- 612 (33), in the definition for “wind barrier,” .F.iii, to ensure that the flat vegetative barrier is sufficient to change the pattern of air flow over the land cover (rooted or unattached vegetative debris lying on the surface with a predominant horizontal orientation that is not subject to movement by wind) equals at least 50% to meet the applicable con trol PM emission control measure requirement

Determination of Standing Vegetative Cover, PCAQCD Code §4

- 9

- 320.B.4 § 4

- 1

- 130.2.F.iii and F.iv, to ensure the standing vegetative cover (rooted vegetation with a predominant vertical orientation) meets minimum percent coverage requirements, depending on the control measure and applicable threshold friction velocity

Silt Content Test Method for Unpaved Roads and Unpaved Parking Lots, in PCAQCD Code § 4

- 9

- 320.A.1 § 4

- 1

- 130.3.A.i, and 4.A.i, to test whether silt loading is equal to or greater than 0.33 oz/ft 2 on unpaved lots and unpaved roads, respectively

, and if equal or greater, to evaluate the percent
silt content

December 21, 2015 Final 80

### 6.2.4 **Credited Annual Emissions Reductions from Fugitive Dust Rule**

Table 6

- 6 Fugitive Dust Rule Attributable Annual Inventory Reductions (TPY) 117

Vacant lots and

open areas Unpaved
lots Unpaved public
roads Paved
road
shoulders Fugitive Dust Rule
SubtotalWindblown dust emissions Developed
Urban Lands 33.8 14.1 0.5 48.4

Developed Rural Lands (low density residential) 25.6 33.6 1.2 60.4

Unpaved Roads 9.4 9.4

Cleared Areas 114. 4 16. 7 0.1 131.2

Desert Shrubland 1

, 554.2 3.2 1

, 557.4

Other 1.8 1.8

1

, 727.9 64.4 7.1 6.8 1

, 808.5Activity-based emissions Paved Road 0.8 0.8

Unpaved Road 1

, 033.3 1

, 033.3

Unpaved

Parking 79.1 79.1

Subtotal 79.1 1

, 133.3 0.8 1

, 213.2

1

, 7 27.9 143.4 1

, 142.7 7.6 3021.7

117 This chart does not reflect the actual reductions in trackout emissions from the fugitive d ust rule. In the construction rule’s credited reductions, the reductions from trackout rule provisions actually reflect reductions from a combination of both the construction and fugitive rules. The creditable emissions were never numerically separated to attribute the respective reductions to each rule.

December 21, 2015 Final 81

## 6.3 **Construction Rule**

**- Contingency** 

**6.3.1 Construction Rule Summary** 

The Pinal County Fugitive Dust Construction Rule (Construction Rule) is a permit based

program. Prior to engaging in any dust generating operations an owner and/or operator shall file a dust generating application and receive a s igned permit from Pinal County. Different requirements apply depending on the size of the work site. All works sites must at least meet a 20% opacity standard for dust generating operations and ensure stabilization using all applicable control measures, in cluding watering before and during operations, applying chemical dust suppressants, altering load

- in/load

- out procedures and watering, reducing vehicular speeds, controlling freeboard and spillage and covering haul vehicles, trackout control device, limiti ng, restricting or rerouting motor vehicles and other measures.



### 6.3.2 **Planned Rule Implementation**

The Pinal County Air Quality Control District filed the rule with the Arizona Secre tary of State

. The hearing/Board of Supervisors meeting to adopt the rule took place on October 28, 2015.

T he rule was published in the Arizona Administrative Register as a final rule, effective January 1,
2016

. 118 Pinal County provide d ADEQ with its rulemaking documentation to submit to the

EPA

. 119



### 6.3.3 **Enforceability**

**6.3.3.1 Authority** 

Per A.R.S. 49

- 479(A), t he Pinal County Board of Supervisors has specific authority, subject to procedural requirements, to adopt and implement rules to control the atmospheric release of air contaminants originating within the Pinal County territorial limits. Pinal County may adopt a
rule that is more stringent than ADEQ’s as long as certain conditions are met . Such conditions
include that the rule is necessary to address a peculiar local condition and there is credible
evidence that the rule is either : (1) necessa ry to prevent significant threat to public health or the environment and the rule is technically and economically feasible, or (2) the rule is required under federal statute or regulation. ADEQ has no similar construction permit

. T herefore

, the permit and authorizing rule are more stringent than ADEQ’s rules. However, t his rule is federally required per C.A.A. §189, insofar as to ensure that ADEQ is able to submit a SIP on behalf of Pinal County for the West Pinal County moderate nonattainment area, and that there are rules in place to control PM emissions for a significant dust generating source such as
construction work sites and associated activity.

118 See Appendix H ; see also Exhibit G

- VII.

119 See Appendix H

.

December 21, 2015 Final 82Per A.R.S. 49

- 473, t he Board of Supervisors additionally has authority to authorize Pinal County Air Qu ality District to carry out the necessary investigations, inspections, and enforcement of any rules adopted pursuant to prevailing statutory authority. Such prevailing statutory authority includes those defining violations and processes for violation cons equences, such as A.R.S. §§ 49

- 502,

- 510,

- 511,

- 513, and

- 514.

**6.3.3.2 Rule Applicability** 

Pinal County’s West Pinal PM10 Nonattainment Area Construction Fugitive Dust rule applies to construction activities generating fugitive dust in the West Pinal PM10 nonattai nment area. Construction, as used in the rule, means building, maintaining, or modifying a capital improvement resting upon, connected to, or buried in the earth.

Different requirements apply to different sized work sites. Work sites 0.1 acres or larger mu st meet a 20% opacity standard and stabilization requirement. Work sites 5 acres or larger must install a trackout device, erect signs or barriers to limit trespass in areas where dust generating operations have ceased for more than 30 days, and ensure the work site is stabilized the day leading up to and the day forecast to be high risk.

**6.3.3.3 Exemptions or Additional Requirements** 

Exemptions from the rule includ e permit requirements for f acilities operating under an industrial permit, as well as road maintenanc e activities (these activities are however subject to applicable standards) , emergency repair of activities (these do not require an application or permit)

, pitched rooftop tile operations, vehicle test and development facilities, non

mechanically adjusted initial landscapes, and in case of an emergency, stabilization actions can be taken before submitting a permit

. There is also an e xemption from the opacity standard in high wind conditions, if the applicable control measures requirements were sufficiently implemented so that disturbed areas are stabilized and one of the following is met: (1) the facility ceases operating un til opacity requirements are no longer exceeded or (2) maintain documentation that the continued dust generating operations are not con tributing to the opacity violation. Such documentation may include onsite opacity observations by a certified
observer.

**6.3.3.4 Alternative Practices** 

A regulated registrant may propose other control measures not specifically listed, as long as the
alternative meas ures are approved by the director of Pinal County Air Quality Control District
and the EPA Administrator.

**6.3.3.5 Notice** 

The definitions and rule requirements are sufficiently clear so as to put the regulated public on
notice. Pinal County has worked closely with industry representatives to ensure the rule is understandable and clear so that the construction industry can comply with it. Industry representatives, Pinal County, and ADEQ intend to conduct outreach to ensure the regulated

December 21, 2015 Final 83construction entities are inf ormed of the rule and how to sign up for the high risk forecast. Where needed, the rule relies on specified test methods to ensure compliance.

**6.3.3.6 Compliance Schedule** 

Per the language of the rule, t he c onstruction r ule will become effective January 1, 2016

. From that point on, the regulated commun ity must comply with the rule. T

**6.3.3.7 Records** 

An owner/operator of a work site shall maintain a copy of his signed permit and shall keep records of every other week inspections and an owner/operator of a work site 5 acres or larger shall also keep records of his site

- wide inspection reports for the day leading up to and of the day forecast to be high ri sk. Upon notice, a n owner/operator shall provide Pinal County with inspection records as soon as practicable, but n o later than 72 hours from the verbal or written notice. The owner/operator shall notify Pinal County of project completion no later than 30 days after completion date. Owners/operators of work sites five acres or larger shall post a project information sign at the work site main entrance, visible to the public.

**6.3.3.8 Test methods and Compliance** 

Compliance is determined by inspection and records review. Failure by any person to comply with the requirements of the rule is a violation and such person is subject to P inal County’s authority to enforce, as listed above. Applicable methods are listed in Table 6

- 7 below.

Table 6

- 7 Construction Rule Test Methods

Test Method Location in the rule and purpose

Visible Crust Determination [The Drop Ball Test] as defined in PCAQCD Code § 4

- 9

- 329.B.1 § 4

- 3

- 170(21), in the definition for “stabilize,” to ensure surface crusting is resistant to wind

- driven fugitive dust

Applicable Opacity Test Method as defined in PCAQCD Code § 4

- 9

- 340 § 4

- 3

- 180(A) , in the recordkeeping requirements
to ensure that work sites do not conduct or allow dust generating operations to result in opacity exceeding 20%



### 6.3.4 **Credited Annual Emissions Reductions**

Those emissions reductions attributable to emissions reductions credited from the Construction
Rule are listed in Table 6

- 8 below.

Table 6

- 8 Annual Inventory Reductions Attributable to Construction Rule (TPY)

ADEQ estimated the following
emissions reductions based on 2018 assumptions (e.g., that 30 miles of unpaved road controls are in place, implemented in 2016 and 2017). Trackout All other provisions Construction Rule Subtotal

December 21, 2015 Final 84Windblown dust Residential
Construction 407.0 407.0

Commercial
Construction 225.1 225.1

Site Development 273.3 273.3

Subtotal 905.4 905.4Activity-basedemissions Paved Road 5.0 120 5.0

Construction 3

, 7 81

. 3 3

, 7

81

. 3

Subtotal 5.0 3

, 7 81

. 3 3

, 7

86

. 2
Total 5.0 4

, 6 86.6 4 4

, 6 91

. 6



## 6.4 **Statutory Amendments**

**6.4.1 Agricultural Best Management Practices** 

**- Arizona Revised**  **Statutes (A.R.S.) § 49**

**- 457** 

The statute establishing agricultural best management practices committee was revised in April
2015. The statute has previously been submitted and approved as a part of the SIP, and the
most recent revisions provide key assurances that facilities will immediately implement the BMPs as mandated under the applicable rules.

The unrevised version of the statute was first submitted on September 4, 1998 and approved

on June 17, 1999. 121 The statute as revised is effective f rom and after January 1, 2016, which is the applicable implementation date of the rules. 122 The revisions since original approval are various and some important revisions include:

1. The Agricultural BMP Committee expanded its size by increasing number of industry representatives,

120 This actually reflects reductions in trackout emissions from a combination of both the construction and fugitive rules, but this number was nev er numerically separated to attribute the respective reductions to each rule.

121 See generally , Approval and Promulgation of Arizona

- Maricopa PM

- 10 Nonattainment Area Implementation Plan, 64 FR 34726, 34732 (Jun. 29, 1999)

122 See, Exhibit G

- IV : A.R.S. §49

- 457 (2015) (effective Jan. 1, 2016); see also Exhibit GIII

- 1 for House Bill 2394, Amending A.R.S. § 49

- 457 (Fifty

- second Legislature, First Regular Session, 2015, Chapter 243, § 1).

December 21, 2015 Final 852. A person engaged in agricultural activity (in a regulated area) shall immediately comply with the agricultural general permit, immediate compliance being effective January 1, 2016,
3. The best management practices general permit must include recordkeeping and reporting requirements,
4. Best management practices and the ensuing program is effective in any nonattainment area for PM10 established after June 1, 2009,

5. Identification of specifically regulated areas within commercial farm s and animal operations , as well as earthmoving activities on commercial farms

, 6. A provision to regulate irrigation districts (irrigation and water conservation districts) and their respective sources of PM , and

7. A more specific definition of regulated agricultur al activities and regulated area.



### 6.4.2 **High Risk Forecast**

**- Arizona Revised Statutes (**  **A .R.S.)**  **§ 49**

**- 424(11)** 

ADEQ has the primary duty to flag high risk forecasts for the West Pinal nonattainment area. The ADEQ

, Air Quality, A ssessment S ection then sends out a ma ss mailing each day informing the public, through Govdelivery.com, as to whether the day is high risk for PM 10 or not. When developing forecasts, ADEQ evaluate s several factors including projected meteorological conditions, existing concentrations of air p ollution at the time of the forecast, and historic air pollution concentrations that have been observed during meteorological conditions similar to those predicted in the forecast. Meteorological conditions considered include wind speed and direction, stag nation, recent and potential for precipitation.

Since A.R.S. § 49

- 424 was last submitted and approved into the SIP

, 123 the high risk forecast section (Section 11) was revised in 2014 to mandate air qu ality dust forecasts for any other

PM 10 nonattainment or maintenance area designated in Arizona after December 31, 2011, in addition to forecasts for the Maricopa County PM 10 nonattainment area.

The statute is referred to in all three of the rule schemas submitted for EPA’s review.



## 6.5 **Adequate Resources 124** 



### 6.5.1 **Ad equate Resources** 

**– Agricultural Rules** 

The costs of the rulemaking to ADEQ and Arizona Department of Agriculture (ADA) will be minimal. ADA is included in this adequate resources discussion because ADA is prescribed
duties in the rule.

123 Partial Approval and Disapproval of Arizona PM Implementati on Plan, 77 FR 66398 (November 5, 2012).

124 See , C.A.A. § 110(a)(2)(E)(i); 40 C.F.R. § 51.280.

December 21, 2015 Final 86ADA and ADEQ will hav e to expend time and monetary resources for revising and printing new guidebooks and for education. ADEQ and ADA staff will have to expend time learning the new rules and ADEQ will have to revise its compliance strategies to implement the rules. ADEQ
estim ates that the current number of full time employees assigned in Compliance Section of the Air Quality Division is adequate to implement and enforce the new rules. ADEQ does enforce agricultural rules throughout the state. However, ADEQ intends to prioriti ze and focus, at least preliminarily and as needed, on agricultural enforcement in West Pinal County to ensure that ADEQ provides the assistance, education, and enforcement necessary to carry out the rules to
reach attainment in the nonattainment area.

AD EQ expects the new recordkeeping costs associated with this rulemaking to be minimal, as the forms have changed minimally, and although they must be turned in to the ADA, it is still

un decided if postage can be covered by ADEQ, ADA, or an electronic delive ry system could be put into place. ADEQ is still developing the survey forms that will be due in 2018 to report on the 2017 year

. Additionally, ADEQ and ADA will have to spend time and resources to compile data from the submitted three year surveys. Of th e recordkeeping costs, this would require the most time and expense.

Overall, ADEQ expects the financial impact of the additional rules to be minimal, even though the rule imposes an administrative burden on the enforcement agency and on the ADA for
collec tion of forms. The general permit that is credited as part of these rules is not fee based, and therefore, the cost of resources will be covered through the use of other budgetary resources at both agencies. ADEQ’s program should be effectively handled by its current personnel without any additional staffing or resources requirements. ADEQ has a sufficient budget to support the program and commits to support the program at least through the next 5

years.



### 6.5.2 **Adequate Resources**

**- Fugitive Dust and Constructio**  **n Rules**

Fugitive dust inspections, response to citizen complaints, primary oversight of dust permit issuance, and enforcement are managed by staff within Pinal County Air Quality Control District Field Services. Field Services consist of a manager (half t ime

- split between monitoring and compliance), and two field inspectors. Field Services inspectors conduct scheduled inspections of permitting activities, complaint

- based inspections, and random inspections of observed activities. Inspectors average in ex cess of 40 inspection s per month depending on variables such as travel time and source complexity. Additionally, a Lead Compliance Engineer placed
within Pinal County Air Quality Control District Permitting oversees fugitive dust compliance at permitted so urces through scheduled and unannounced inspections. Over

- the

- counter construction dust permits are issued each day during normal business hours at the main office and one day per week at two satellite offices by a rotating assignment of department wide

st aff. During the in

- person permit application and issuance process applicants are provided guidance for compliance.

The current staffing level has been in place since 2010 coinciding with the slowdown in construction activity in Pinal County. Construction projections in the county show a slow to

December 21, 2015 Final 87moderate increase over the next 5 years. Projecting 1, 3, and 5 years into the future, Pinal County anticipates sustaining the current effort to conduct scheduled inspections of permitted dust sources as well as pro active inspections of area dust emissions. With the current level of dust permits issued annually, the staffing level will be sufficient in future years.

December 21, 2015 Final 88

## 7 **ATTAINMENT DEMONSTRATION AND REASONABLE**
**FURTHER PROGRESS**

Effective July 2, 2012, the EPA redesignated the West Pinal area from an unclassifiable area to a moderate nonattainment area. This action required Arizona to demonstrate (1) that the plan will provide for attainment as expeditiously as practicable but no later than the attainment
date

, 125 or a demonstration that attainment by such date is impracticable, 126 and (2) quantitative milestones , which demonstrate reasonable further progress (RFP) toward timely attainment, 127 that are to be achieved every 3 years until the area is redesignated

a ttainm ent. 128

ADEQ has demonstrated attainment no later than December 2018 and has verified sufficient annual incremental emission reductions to satisfy reasonable further progress requirements.



## 7.1 **Attainment Demonstration**

This section briefly describes the methods for demonstrating and modeling attainment in the West Pinal Nonattainment Area, with attainment expected no later than December 2018

. More specifically, this chapter explains ADEQ’s steps in determining modeling domains and methodologies, including how modeling design days were chosen, as well as how the controls from the recently revised Agricultural Best Management Practices Committee rules (collectively referred to hereinafter as the “AgBMP rules”) were account ed for in the attainment demonstration. The West Pinal AgBMP rules, except for the dairy applicable section, are the only rules used to demonstrate attainment in this SIP. 129 More discussion regarding the AgBMP

r ules themselves can be found in Chapter 6 of this document and also the RACM Document, Appendix F.

Inventory analysis showed that two distinct meteorological scenarios produced concentrations
i n excess of the 24

- hour PM 10 National Ambient Air Quality Standard (NAAQS) of 150μg/m 3 : high wind and stagnation conditions. The emission sources responsible for the elevated concentrations are fundamentally different under these two scenarios

. 130 Therefor e, t he two meteorological scenarios required the use of different design days, for which monitor

- specific

125 i.e. end of December 2018. See , C.A.A. § 188(c)(1) (2012) (“For a Moderate Area, the attainment date shall be as expeditiously as practicable but no later than the end of the sixth calendar year after the area’s designation as nonattainment...”).

126 See C.A.A. § 189(a)(1)(B) (2012).

127 As defined in C.A.A. § 171(1) (2012).

128 See C.A.A. § 189(c)(1) (2012).

129 Emissions reductions resulting from the dairy operations s ection, A.A.C. R18

- 2

- 611.03(D), have been applied toward contingency measures instead of attainment. More information on contingency measures is contained in Chapter 6 of the SIP main body and Appendix D.

130 See Appendix A (IPP), Section 3.2, p. 50, for more information.

December 21, 2015 Final 89inventories were developed

, with separate concentration calculation methodologies utilized for high wind and stagnation design days

. D ifferences in so urce mix and the range of meteorological conditions affecting emissions in the area guided the decision to select at least one stagnation and one high wind design day for each nonattaining monitor

, as applicable per
exceedance data. 131



### 7.1.1 **Stagnation Attainment Modeling Background** 

**7.1.1.1 Stagnation**  **Condition Description**

During stagnation periods, when wind speeds are typically below 3 mph, wind entrainment of loose soil particles is virtually nonexistent and mechanical sources that lift particles into the air through combustion, vehicle movement, and other anthropogenic activities are primarily responsible for recorded concentrations. Particles accumulate in the air without any meteorological reprieve during stagnation periods.

**7.1.1.2 Stagnation**  **Design Day Selection**

After an alysis of all stagnation day exceedances in 2008, three monitors exceeded the 24

- hour

PM 10 NAAQS

. T wo days were found to be the most representative after isolating quality assured data and noting that there were no high wind speed hours recorded on the sel ected days. 132 The meteorological conditions were most representative for the Pinal County Housing and Stanfield monitors on October 29, 2008. Cowtown also exceeded on October 30, 2008. However, the closure of several significant emission sources near the C owtown monitor between 2008 and 2011 and the continued recording of 24

- hour PM 10 exceedances at the
monitor caused a reassessment of the October 29, 2008 design day for that monitor. October 30, 2008 exhibited similar meteorological conditions and was foun d to be most representative
for the Cowtown monitor. 133

The sites and dates for the selected stagnation design days are listed below:

• Pinal County Housing

- October 29, 2008

• Stanfield

- October 29, 2008

• Cowtown

- October 30, 2008

No PM 10 exceedances occur red on stagnation days at the Maricopa, Casa Grande, or Combs School monitoring sites, and therefore these monitors were not included in the list of low wind speed attainment demonstrations. 134

131 See Appendix A (IPP), Section 3.2, p. 50

- 51, for more information.

132 See Appendix A (IPP), Section 3.2, p. 52, for more informatio n.
133 See generally Appendix B (EI TSD) Section 2.2; see also Exhibit B

- XIII.

134 See Appendix A (IPP), Section 3.3, p. 51, Table 3

- 2.

December 21, 2015 Final 90The closure of several significant emission sources near the Cow town monitor between 2008 and 2011 and the continued recording of 24

- hour PM 10 exceedances at the monitor caused a
reassessment of the October 29, 2008 design day for that monitor. The resulting analysis, presented in Exhibit 12, led to the selection of O ctober 30, 2008 to represent low wind
conditions at the Cowtown monitor. 135

**7.1.1.3 Stagnation**  **Domain Boundary Selection**

Separate domains were defined for each of the three selected monitors. To define low wind domains for the modeling inventories, rectangular boun daries were demarcated based on the maximum hourly distance traversed by wind parcels from the monitor to the source. 136 Transport distances are relatively short under low wind conditions, therefore only those
sources within close proximity (varying by monitor’s modeling domain) of a monitor contribute to high hourly PM 10 concentrations during stagnation conditions. 137

T he Cotton Research and Protection Council (CRPC) characterized crops under cultivation in
2008 for a 6 km radius (3.7 mi) su rrounding the nonattaining monitors of Cowtown, Maricopa, Pinal County Housing, and Stanfield

. CRPC data did not include characterization of crop lands outside of this 6 km boundary or Indian Reservation crop lands . Assumptions for nonidentified agricultu ral lands and additional sources on Gila River Indian Community and AK

- Chin land, such as unpaved roads and point sources are descr ibed in Section 3.1.1.13 of Appendix B ( EI
TSD )

.

**7.1.1.4 Stagnation**  **Model Method Selection**

**- AERMOD** 

After review of EPA guidelines an d fugitive dust modeling demonstration in MAG plans, ADEQ
decided that AERMOD is the most suitable model for evaluating hourly source con tributions to

PM 10 exceedances recor ded at Pinal County monitors on stagnation design days. AERMOD, a steady

- state Gau ssian plume dispersion model that assesses pollutant concentrations from a variety of source types, is very effective for predicting emissions during near calm conditions. 138

On stagnation days, AERMOD was run with meteorological data recorded at the subje ct monitor and emissions rates for each source within the modeling domain, as calculated from reported activity data and best

- representative emissions factors. 139 A domain specific average emissions rate was computed for the crops included within the CRP C do mains and was applied to each agricultural crop parcel in the tribal domain. Small portions of the modeling domains fall outside of the CRPC boundary so assumptions about crop activity on agricultural lands outside the boundary were needed. 140

135 See generally Appendix B (EI TSD), Section 2.2.

136 See generally Appendix B (EI TSD), Section 1.1.

137 See generally Appendix A (IPP), Section 3.2.

138 See generally Appendix C (Modeling TSD), Section 2.

139 Appendix C (Modeling TSD), p. 2.

140 See generally Appendix B (EI TSD), Sections 3.1.1.1 and 3.1.1.13.

December 21, 2015 Final 91**7.1.1.5 Stagnation**  **Mod eling Inventory** 

The stagnation inventory methodology follows closely to that described in the activity based emissions annual inventory described in Chapter 5 , except that the inventories for modeling purposes were developed specifically for the individual monitor modeling domains and emission rates were developed at an hourly scale

. 141

**7.1.1.6 Other**  **Stagn ation Modeling Factors** 

Emission methodologies for calculating activity based fugitive dust for all land use categories are described in section 3.1.1 of Appendix B (EI TSD). Any changes in dust generating activities between 2008 and 2018, other than additi onal controls resulting from this plan, are described in Section 3.2.1 of Appendix B (EI TSD).



### 7.1.2 **High Wind Attainment Modeling Background**

**7.1.2.1 High**  **Wind Day**  **Condition Description**

During high wind conditions, windblown dust emissions from disturbed soil surfaces typically
dominate PM 10 emissions. Windblown dust emission magnitude is directly proportional to wind velocity

, disturbed surface area, and the soil texture. 142 Sources within a narrow band along the upwind trajectory tend to contribute significantly to reco rded PM 10 concentrations, because of the tendency of wind trajectories to remain somewhat constant during these periods. 143 High wind days are comprised of both high wind hours (including windblown and activity emissions)
and low wind hours (containing only activity emissions)

. 144

**7.1.2.2 High**  **Wind Design Day Selection**

To identify high wind days, the PM 10 exceedance days recorded at each of the six nonattainment monitoring sites were screened for high hourly average wind speeds (over 12 mph) during hours of high PM10 concentrations. 145 The analysis of PM 10 exceedances on high wind days selected four monitors determined to be representative of conditions throughout the year, at the sites and dates listed below. 146

• Cowtown

– April 27, 2008

• Pinal County Housing

– January 1, 2008

• Stanfield

– November 21, 2008

• Maricopa

– October 27, 2008

141 See generally Appendix B (EI TSD), Sections 3.1.1 and 3.2.1.

142 Appendix A (IPP), Section 3.4, p. 52.

143 Appendix A (IPP), Section 3.2, p. 50.

144 See generally Appendix B (EI TSD), Section 2.1.

145 Appendix A (IPP), Section 3.4, p. 52.

146 See Appendix A (IPP), Sections 3.5 through 3.9 for information on the methodology of choosing representative
dates.

December 21, 2015 Final 92**7.1.2.3 High**  **Wind Domain Boundary Se lection** 

7.1.2.3.1 High Wind Hour Domains

A relatively complex approach was used to define domains for high wind days. The domain for the high wind hours in the West Pinal nonattainment area followed the methodology that Maricopa Association of Governments (MAG) use d in the 2012 Five Percent Plan, 147 which plotted a back trajectory based on the average wind speed and direction recorded for each high
wind hour. 148

GIS shapefiles developed by PCAQCD and ADEQ provided land use information for the entire
nonattainment area . However, outside of the 6 km radius supplied by CRPC , no information was available for specific crops under cultivation on agricultural lands. This is problematic as particulate s transport further under high wind conditions

, and agriculture is the domin ant land use within the nonattainment area. Agricultural windblown emissions are strongly affected by specific crops under cultivation. 149

Transport analysis determined that 80% of the impacts, assuming equivalent source strength,
would come from sources lo cated within 4 miles of a 12 mile upwind trajectory 150 . Little insight would be gained from characterizing sources beyond the 6 km (3.7 miles). Therefore, ADEQ
decided to restrict the size of the domain to relevant boundaries within the 6 km CRPC area

, all owing for the specific domain shape and size definition

. 151 Using the approach, a triangular domain extends from each monitor along the high wind trajectory hours reflecting the monitor specific design day data. The domain is bounded by a 6 km arc. 152 Some o f the area within the domains was actually Gila River Indian Community (GRIC) land

. 153 ADEQ could only collect limited information from the GRIC, therefore, assumptions were applied for land uses within
GRIC land. 154

7.1.2.3.2 Low Wind Hour Domains 155

Unlike the high wi nd domains where wind direction and emissions are consistently from a single quadrant, wind and emissions impacting the monitor during low wind hours come from all directions, similar to stagnation emission impacts. A rectangular domain is defined by the maximum hourly wind directions and speeds. The domain is considerably larger than the 6 km

147 MAG 2012 Five Percent Plan for PM 10 for Maricopa County Nonattainment Area, Maricopa Association of Governments, May 2012.
148 See Appendix B (EI TSD) for more information on domain methodology development.

149 See generally Ap pendix B (EI TSD), Section 2.

150 See generally Appendix B (EI TSD), Section 2.1

151 See generally Appendix B (EI TSD), Section 2.1

152 See generally Appendix B (EI TSD), Section 2.1

153 See generally Appendix B (EI TSD), Section 2.1

154 See generally Appendix B (EI TSD), Section 3.1.1.13.

155 Low wind hours are assigned a high wind day domain because high wind days are comprised of both high and
low wind hours.

December 21, 2015 Final 93radius of crop data provided by CRPC. 156 Assumptions were required for land outside of the
information from CRPC. 157

L ow wind hour activity emissions are estimated using the same methods as activity emissions

on stagnation days. However, low wind hours take place on high wind days (or non

- stagnation days). Because not every hour of a high wind day will have wind speeds of 12 mph or more , calcu lated activity emissions from low wind hours and high wind hours are added to high wind
hour windblown dust emission totals.

**7.1.2.4 Model**  **Method Selection**

**- Rollback** 

The method used to assess high wind hour source apportionment and to provide a basis for
demons trating attainment is the weighted rollback method , a n approach that was employed in
MAG’s Five Percent Plan 158 and approved by EPA. 159 In MAG’s experience, neither AERMOD nor photochemical grid models performed well to quantify specific area source contribut ions to
monitors during high wind s , and in fact were unreliable. MAG developed a more reliable rollback approach. 160

The weighted rollback approach applies a distance reduction factor to the emissions of each source in the modeling domain to help assess the impact of emissions as distance from the
monitor increases. 161 The approach weights the contribution of each upwind source’s emissions by the reciprocal of its distance to the monitor and assumes that each source’s fractional contribution to the sum of weig hted emissions is equal to that source’s fractional contribution to the hourly PM 10 concentration measured at the downwind monitor (i.e., that the impacts of emissions from nearby sources are proportionally greater than the impacts from remote

sources, ass uming equivalent emissions rates among sources). 162

In contrast to Maricopa County

, which had not experienced a low wind violation of the PM10 standard since 2007, Pinal County experienced violations on both stagnation and high wind days . A review of high wind day hours revealed that low wind hour concentrations on high wind days sometimes exceeded high wind hour concentrations at each of the monitors. Based on this finding, decisions were made (1) to model the effect of low wind hour mechanically gene rated emissions and (2) to model both mechanically generated emissions and windblown dust emissions during high wind hours. 163

156 See generally Appendix B (EI TSD), Section 3.1.2.

157 See generally Appendix B (EI TSD), Sect ions 3.1.1.1 and 3.1.1.13.

158 Maricopa Association of Governments, MAG 2012 Five Percent Plan for PM

- 10 for Maricopa County Nonattainment Area, Section 6, Attainment Demonstration (May 2012).

159 See Appendix C (Modeling TSD), Section 3.1.

160 Id

. 161 See genera lly Appendix C (Modeling TSD), Section 3.1, p. 27.

162 See Appendix C (Modeling TSD), Section 1, p. 2.

163 See Appendix C (Modeling TSD), Section 3.1, p. 28.

December 21, 2015 Final 94Therefore, for both high wind hours (>12 mph) and low wind hours (≤12 mph) on high wind days, the weighted rollback method was used to assess the relative contribution of each upwind source to the hourly monitored PM 10 nonattainment area. 164

The rollback method as applied assumes (1) emission factor uniformity within “disturbed” and “undisturbed” states of surface soil conditions and ( 2) an inverse relationship between the source’s distance from the monitor and the emission impact at that monitor. 165

Because the calculation of windblown emissions can be tricky to follow, below is an example high wind calculation for disturbed agricultur al land.

Example Windblown Calculation for Disturbed Agricultural Land:

Assume calculation of the hourly windblown emissions from a 50 acre (202,343 m 2 ) cotton field located 1.3 miles directly upwind of the Pinal County Housing (PCH) monitor during harvest ing season for a single hou r averaging 22 mph wind speed. This is the fourth consecutive hour of high winds (i.e. >12mph) for this wind event and one hour following the maximum measured concentration for this wind event at the PCH monitor. The harvesting s eason is assumed to have fully disturbed soil, so use of Equation 1 on page 3

- 90 of Appendix B is appropriate (Note: For those lands determined to be partially disturbed, Equations 1 and 2 on page 3

- 90 and 3

- 91 of Appendix B would be employed and the area utilized in each equation would be the product of the area of the parcel and the disturbed fraction and stable fraction of the land of interest, respectively.)

EE ssss = FF EEEEEEEE EE EEEEEEEEEE × AA × EE DDDD DDDD × VV ′

w h e r e : Esj = s uspe n d e d PM 10 in g r a m / s e c f o r hour j

F

EFAdjustment = the emission adjustment factor for diminished particle supply (detailed in Appendix B, Exhibit B

- VII)

A = the a rea of e ac h c ro p ’s l a nd p a rc e l, in m 2

E F D i s tu r b e d,bin = t he windbl o wn dust emission f ac tor d e v e loped f o r disturb e d s oil f or a given wind sp ee d bin, g r a m / m 2

- s e c for h our j ( d e tailed in Appendix B, Exhibit B

- V )

V’ = crop specific v e g e tative c ov e r, presented in Appendix B, Table 3

- 48

Table 7

- 1 Values used for Example Windblown Dust Calculation

Variable Value Units Source

164 See Appendix C (Modeling TSD), Section 1, p. 2.

165 See Appendix C (Modeling TSD), Section 1, p. 2.

December 21, 2015 Final 95F EFAdjustment 51 % Appendix BVII, Table BVII

- 4

A 202,343 m 2 Given in assumptions (area of the field)

EF Disturbed,bin 4.27E

- 04 g/m 2

- s Appendix BV, Table BV

- 4

V' 0.7 Unit

- less Table 3

- 48

Using the values presented in Table 7

- 1 and the equation above, we can calculate windblown emissions from the cotton field during this single hour of high wind as:

EE

ssss = 0

. 51 × 202

, 343 mm 2 × 0

. 000427 gg

mm 2

− ss × 0

. 7 = 30

. 8 gg

ss × 3600 ss h rr ÷ 453

. 6 gg llll = 244 llll

h rr

The emissions produced within that hour are 245 lbs. This can then be modeled as monitor impacts by dividing by the straight

- line distance to the monitor (1.3 miles). This results in a monitor impact of 188 lb/mile.

If this im pact was assumed to occur on the 2008 Pinal County Housing (PCH) high wind design day and only assumed to occur for this one hour, we can normalize this impact to the monitor by dividing the individual cotton field’s impact calculated above by the total e mission impacts on the monitor for that day (25,258 lb/mile; calculated as the sum of the hourly total impacts presented in Appendix C (Modeling TSD), Section 3.3, Table 3

- 1) multiplied by the non

b ackground monitor 24

- hour average (247.4 μg/m 3 ) 166 . This re sults in a 24

- hr average impact of this single cotton field on the monitor of 1.8 μg/m 3 for the PCH design day.

**7.1.2.5 High**  **Wind Modeling Inventory**

With some Pinal specific revisions detailed in the technical supporting documents, 167 ADEQ closely followed MAG’s 201 2 5% PM10 Plan high wind methodology to model for an inventory and to identify significant sources within the nonattainment area. ADEQ calculated and adjusted high wind emissions factors utilizing the methodology described in Chapter 5

. T o model source impacts on the monitor, design

- day specific meteorological information from a respective monitor was used in conjunction with design

- day calculated emission rates for each parcel within the monitor’s modeling domain

. 168 Land use categorization determines the
disturbed versus stable land

, in turn defining hourly emission rates . Emission methodologies fo r calculating high wind fugitive dust for all land use categories are described in Section 3.1.2 of Appendix B (EI TSD).

166 247.4 μg/m 3 is calculated as the design day concentration (264.9 μg/m 3 ) minus the calculated non

anthropogenic background on high risk days (17.5 μg/m 3 ), See Appendix C (Modeling TSD) Section 3.2 for more
information.

167 See Appendix B (EI TSD), Section 3. 1.2, p.109

- 110.

168 See Appendix A (IPP), p. 3.

December 21, 2015 Final 96**7.1.2.6 Other**  **Factors**

Emission methodologies for calculating high wind fugitive dust for all land use categories are described in section 3.1.2 of Appendix B (EI TSD). Any changes in high wind emissions between 2008 and 2018, other than additional controls resulting from this plan, are described in Section 3.2.2 of Appendix B (EI TSD).



### 7.1.3 **How ADEQ Accounted for Attainment Controls**

Generally, attainment was modeled using the rules applicable to crop and animal operations, except for dairy operations (these were used for contingency measures). Please find a more detailed discussion regarding the Agricultural Rules themselves in Chapte r 6 of this document, the RACM Document, Appendix F, and the Notice of Exempt Rulemaking, Exhibit G

- VI

.

**7.1.3.1 Crop Operations** 

In order to estimate com mercial crop farm emission reductions associated with the implementation of this rule, ADEQ required an understanding of which BMPs a commercial crop farmer would be most likely to implement for each operation. With the help of the Agricultural Best Manag ement Practices Committee (Ag BMP Committee), ADEQ surveyed Pinal County crop farmers to determine the likelihood of individual BMP implementation. Farmers were surveyed to determine the likely BMP strategies they would implement on individual

crops on non

- high wind and high wind forecasted days. Survey responses were separated by crop type. Weighted average control efficiencies for each crop type were calculated and applied to the emission rates for those individual crops and activities. The control effici encies were weighted based on survey responses regarding crop acreage and the number of responses given for each crop type and associated regulated activity. For more information regarding the crop operations survey methodology, please see Section 3.1.1.1 of Appendix D (Attainment Demonstration TSD).

In additions, crop operation activity, distribution, and acreage were assumed constant between 2008 and 2018. For 2018 controlled calculations, however, high risk control efficiencies were applied to design d ay activity and windblown emissions under the assumption that all design days would be forecast as high risk. For windblown emissions, the implementation of the AgBMP rule resulted in reduced windblown dust emissions from croplands due to the implementatio n of BMPs that either reduced emissions through ground stabilization or increased ground cover.

**7.1.3.2 Confined**  **Animal Feeding Operations (CAFOs)**

Cattle populations on CAFOs in the nonattainment area in 2018 are expected to be 38% lower than in 2008, due mainly t o the closing, consolidating, or repurposing of half of the feedlots.
These closures also reduced windblown dust emissions from the former feedlot sites. For windblown modeling purposes, these locations were assumed to transition from the CAFO land

use to the Cleared Areas land use category.

December 21, 2015 Final 97Based on a poll of the CAFO operators who still have active operations in the NA (there are only 3), ADEQ developed a most likely profile of operational changes that would be in place by 2018 to facilitate compliance with the new state AgBMP rule. These include a combination of watering practices and cleaning schedule changes, as well as traffic controls. For 2018 controlled calculations, however, high risk control efficiencies were applied to design day activity and w indblown emissions under the assumption that all design days would be forecast as high risk. Based on the estimated number of high risk days, ADEQ estimated that in annual

terms (not design days) , 2018 controls would be 15.5% more effective than 2008 contr ols in reducing activity

- driven dust, and 10 .1 % more effective for windblown dust.



### 7.1.4 **Comparative Concentration Table**

Below is a table comparing the past and projected design value concentrations between the 2008 base year, the projected 2018 base year, and t he projected

- controlled year 2018. The projected

- controlled 2018 year only accounts for attainment controls, and no contingency
controls.

Table 7

- 2 Comparative Design Day Concentration between Base 2008, Proje cted 2018, and Projected Controlled 2018

Year Design day Background
concentration (μg/m3) Design value (μg/m3)2008Stagnation Cowtown

11.5 244.5Monitor observations Pinal County Housing 178.0

Stanfield 162.0High-Wind Cowtown

17.5 168.3
Maricopa 159.4 Pinal County Housing 264.9

Stanfield 178.62018Stagnation Cowtown

11.5 188.4Modeled projections Pinal County Housing 179.6

Stanfield 197.7High-Wind Cowtown

17.5 16 3.7
Maricopa 140.0 Pinal County Housing 26 2.7

Stanfield 186.0-Attaingnati Cowtown 11.5 152.5edproj

December 21, 2015 Final 98Pinal County Housing 154.9

Stanfield 154.7High-Wind Cowtown

17.5 120.8
Maricopa 124.3 Pinal County Housing 135.3

Stanfield 112.2



### 7.1.5 **Annual Inventory Attainment Reductions**

Below is a table reiterating the amount of reductions achieved by the agricultural rule alone ( not including provisions applicable to dairy operations or canal access roads)

.

Table 7

- 3 Annual Inventory Reductions from the Attainment Targeting Sections of the Ag BMP Rules (TPY)

Land Use/Source Category Unpaved

apron roads Unpaved
canal
O&M
roads Harvesting and Tilling CAFOsWindblown Dust Unpaved Roads 705 .2 144.7

CAFOs 29.9 Agriculture 12388.1
Subtotal 705 .2 144.7 12388.1 29.9Activity-basedemissions Ag Fields

- Harvesting 105.8 Ag Fields

- Tilling 882.3

CAFOs 251.4 Unpaved Roads 7341.3 577.6
Subtotal 7341.3 577.6 988.1 251.4
Total 8045.5 722.3 13376.2 281.3
Grand Total 22426.3



## 7.2 Reason **able Further Progress**

Under section 189(c)(1), this nonattainment plan must demonstrate Reasonable Further Progress ( RFP ), which “ means such annual incremental reductions in emissions of the relevant air pollutant as are required by this part or may reasonably be required by the Administrator for

December 21, 2015 Final 99the purpose of ensuring attainment of the applicable national ambient air quality standard by the applicable date .” 169

EPA has stated in guidance, “where the nonattainment problem is attributed to area type sources (e.g., fugitive dust, residential wood combustion, etc.), RFP should be met by showing annual incremental emission reductions generally sufficient to maintain linear progress towards
attainment. Total PM

- 10 emissions should not remain constant or increase from 1 year to the
next in such an area." 170 The a nnual incremental emission reductions to be achieved should be reasonable in light of the statutory objective to ensure timely attainment of the PM 10 NAAQS. 171

The West Pinal nonattainment area is projected to reduce emissions to meet attainment within a three year period, with annual inventory reductions totaling 22,42 6

. 3 tons over the three years. With a three

- year horizon from the end of 2015 to modeled attainment at the end of 2018, a linear implementation schedule would require a glide path showing annual reductions
7475.4 tons per year.

The actual implementation plan causes an acute reduction in the first y ear, from the end of 2015 to the end of 2016, followed by slow and steady reductions until the end of 2018. The actual implementation and emissions reductions path is projected to be quite steep in the first year because the measures credited toward attain ment, the agricultural rules, are more fitted for upfront reduction credit. In the relatively short amount of time within which the West Pinal
nonattainment area must reduce PM 10 emissions to meet the attainment date, the chose n glide path in Figure 7

- 1 below is the most reasonable solution and representation of reasonable further progress to meet attainment.

169 C.A.A. § 171(1) (2012).

170 Proposed Approval of Maricopa County PM10 Nonattainment Area Five Percent Plan, 79 FR 7118 at 7123 (Feb. 6, 2014).

171 Addendum to the General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990, 59 FR 41998, 42015 (Aug. 16, 1994).

December 21, 2015 Final 100Figure 7

- 1 Reasonable Further Progress from Dec. '15 through Dec. '18

Figure 7

- 2 : Reasonable Further Progress from Dec. '15 through Dec. '18

Reasonable Further Progress qualitative milest ones must be achieved every three years. In the case that the agricultural rules developed for attainment under this plan do not alone allow for the achievement of qualitative milestones every three years , contingency measures will already be in place to a ssure attainment

. If an area fails to make reasonable further progress, CAA Section 172(c)(9) requires the implementation of contingency measures. EPA recommends that contingency measures for

PM 10 nonattainment areas provide emission reductions equivalen t to one year's average
increment of RFP

. 172 EPA has further interpreted section 172(c)(9) to allow states to implement contingency measures before they are triggered by a failure of RFP or attainment as long as

172 Addendum to the General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990, 59 FR 41998, 42014 (Aug. 16, 1994). 105,000 110,000 115,000 120,000 125,000 130,000 135,000 140,000

2015 2016 2017 2018Annual NA-Wide Emissions (TPY) Glide Path Actual Implementation Schedule

December 21, 2015 Final 101those measures are intended to achieve reducti ons over and beyond those relied on in the
attainment and RFP demonstrations. 173

ADEQ has provided for additional emissions controls and consequent reductions that will ensure continued progress toward attainment and RFP past the attainment date until the W est Pinal Area is redesignated. These measures include the agricultural dairy controls, the Pinal County construction controls, trackout controls, and most of all, the Pinal County General Fugitive Dust Rule. The reductions from all of these rules and pro visions is projected to total 7,474.8 by 2018 , as shown in Table 7

- 4 below. 174

Table 7

- 4 Summary of Contingency Measure Reductions

Rule Controlled Dust Sources Implementation
date Reductions in 2018 (TPY)

Arizona Administrative

Code, R 18

- 2

- 611.03 C ommercial dairy operations January 1, 2016 101.2

PCAQCD Code of Regulations, §4

- 3

- 160,

- 170,

- 180, and

- 190 Permitted c onstruction projects January 1, 2016 4

, 679.4 175

PCAQCD Code of Regulations, §4

- 1

- 010,

- 015,

- 020,

- 030,

- 040,

- 045,

- 050, and

- 060 Several prescribed area
sources of f ugitive dust, including vacant lots and other open areas, roads,
and other traffic areas. Effective January 1, 2016, with some controls being implemented progressively 2,962.3

Total 7

, 742.9

In addition, PM 10 nonattainment SIPs are required by section 189(c) to contain quantitative milestones to be achieved every three years and which are consistent with RFP for the area. These quantitative milestones should consist of elements which allow progress to be quant ified
or measured. 176 The quantitative milestones are "to be achieved until the area is redesignated
attainment." 177

According to current EPA policy, the three year quantitative milestone report requirement runs from the nonattainment SIP submittal due date, 178 which

, in this case, was 18 months from the

173 See Proposed Approval of Mari copa County Serious Nonattainment Area Plan, 75 FR 54806, at 54815 (Sept. 9, 2010). See generally

, LEAN v. EPA, 382 F.3d 575 (5th Cir. 2004). See also General Preamble for the Implementation
of Title I of the Clean Ai r Act Amendments of 1990, 57 Fed. Reg. 13,498, at 13512.

174 For more information regarding the details of contingency measure calculations to meet one year’s worth of RFP, please see Appendix D, Section D5.2.

175 Up to 5 TPY of reductions attributed to the co nstruction rule may actually be attributable to the general fugitive dust rule instead, but were consolidated in the construction rule subtotal as an expediency. See Appendix D
Sections D5.2.2.1 and D5.2.3.4 for details.

176 Addendum to the General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990, 59 FR 41998, 42016 (Aug. 16, 1994).

177 C.A.A. § 189(c) (2012).

178 Fine Particulate Matter NAAQS SIP Requirements, 80 FR 15340, 15390 (proposed Mar. 23, 2015).

December 21, 2015 Final 102effective redesignation date , July 12, 2012 . To align with th e policy, the ADEQ intends to submit West Pinal PM10 milestone report in the beginning of 2017. ADEQ’s report will adequately quantify and track prog ress with its RFP goals. ADEQ anticipates submitting a report that first, demonstrates how emissions reductions achieved by the beginning of 2017 compare to those scheduled, second, analyzes the correlation between the plan and monitoring data, and third, projects whether the area will still meet its scheduled attainment date, also taking into account the already implemented contingency measures.

Generally, ADEQ intends to analyze chosen agricultural BMPs and reduction progress using the agricultural rule ’s surveys. In the absence of adequate or representative data, ADEQ expects to use apropos compliance data. For example, ADEQ anticipates reporting on the number of producers in compliance at the time of inspection, according to the chosen attainment

measu res, A.A.C. R18

- 2

- 610,

- 610.03,

- 611,

- 611.03(A), (C), & (E)

- (O),

- 612, and

- 612.01(A)(1) & (B)

- (J). In the event it is more accurate than survey data, ADEQ also anticipates using inspection data and/or data from the General Permit Record Forms as reviewed during inspections in order to determine which PM10 reducing BMPs inspected agricultural operations use. From this data, ADEQ may estimate reductions and compare these figures to the projected reductions in this plan.

December 21, 2015 Final 103