C FINAL 

I PLAN FOR ATTAINMENT OF 

1 THE 24-HOUR PMfo STANDARD 

1 MARICOPA COUNTY 

I PM,o NONATTAINMENT AREA 

A@ Quality Division 

Arizona DepaNnent of Environmental Quality 

in Cooperation With 

Maricopa County Environmental Services Department 

May, 1997 
-- . - 

TABLE OF CONTENTS 

EXECUTIVESUMMARY ....................................... ES-1 

1.0 INTRODUCTION ............................................ 1 

1.1 Ober v . EPA ............................................ 1 

1.2 Overview of Microscale Study ............................... 3 

1.3 Overview of Attainment Demonstration ......................... 5 

1.3.1 Approach ........................................ 5 

2.0 DUST CONTROL PRACTICES IN MARICOPA COUNTY ................ 7 

2.1 Rule 3 10. Open Fugitive Dust Sources ......................... 7 

2.2 MCESD Implementation and Enforcement of Rule 3 10 ............... 9 

2.2.1 Earthmoving Permit Application ......................... 9 

2.2.2 MCESD Enforcement Staff and Activities .................. 10 

2.2.3 MCESD Inspector Training ........................... 13 

2.2.4 MCESD Databases ................................ 10 

3.0 RESULTS OF MICROSCALE STUDY ............................. 14 

3.1 Air Quality Modeling Results .............................. 15 

3.1.1. East Chandler Site ................................ 16 

4.0 EVALUATION OF DUST CONTROL MEASURES FOR DESIGN DAYS ....... 20 

4.1 Control Measures ...................................... 21 

4.2 Discussion of Control Measures and Implementation Issues ........... 23 

4.2.1 Salt River Site. October 16. 1995 ....................... 23 

4.2.2 Gilbert Site. April 9. 1995 ............................ 23 

4.2.3 Maryvale Site. April 9. 1995 .......................... 27 

4.2.4 West Chandler Site. April 9. 1995 ...................... 28 

5.0 PROPOSED BEST AVAILABLE CONTROL MEASURES ................ 29 

5.1 Regulatory Requirements ................................. 29 

5.1.1 Reasonable Further Progress and Quantitative Milestones ....... 29 

5.1.2 BACM Analysis .................................. 30 

TOC- I 
TABLE OF CONTENTS. CONTINUED 

5.2 Implementing Agencies .................................. 31 

5.2.1 Agricultural Community ............................. 31 

5.3 BACM Commitments and Enforceability Documentation ............. 31 

5.3.1 Maricopa County Environmental Services Department .......... 32 

5.3.2 Cities and Towns of Maricopa County .................... 35 . 5.3.3 Arizona Department of Environmental Quality ............... 35 

5.3.4 Agricultural Community ............................. 36 

6.0 ATTAINMENT DEMONSTRATION .............................. 37 

6.1 Salt River Site. October 16. 1995: Attainment Demonstrated .......... 37 

6.2 Gilbert Site. April 9. 1995: Attainment Not Demonstrated ............ 38 

6.3 Maryvale Site. April 9. 1995 : Attainment Demonstrated ............. 38 

6.4 West Chandler Site. April 9. 1995: Attainment Not Demonstrated ....... 39 

FIGURES 

Figure 1-1 Maricopa County PM.. Nonattainment Area ...................... 4 

Figure 2-1 Current Dust Control Plan Form ............................ 11 

Figure 5-1 Improved Dust Control Plan Form ........................... 34 

TABLES 

TABLE 3-1: 24-Hour PM,, Exceedances in 1995 

Maricopa County's Monitoring Network ....................... 16 

TABLE 3-2: Air Quality Modeling Results for Maximum Concentration at Salt River Site 

onOctober 16. 1995. DesignDay ........................... 18 

TABLE 3-3: Air Quality Modeling Results for Maximum Concentration at Gilbert Site 

on April 9. 1995. Design Day .............................. 18 

TABLE 3-4: Air Quality Modeling Results for Maximum Concentration at Maryvale Site 

on April 9. 1995. Design Day .............................. 19 

TABLE 3-5: Air Quality Modeling Results for Maximum Concentration at West Chandler 

Site on April 9. 1995. Design Day ........................... 20 

TABLE 4-1: PMlo Emission Control Measures for Sources 

Contributing to Design Day Exceedances ....................... 21 
I 

I 

TABLES, CONTINUED 

TABLE 4-2: Application of Added Control Measures to Attain 24-Hour PM,, NAAQS at 

I Salt River Site on October 16, 1995 Design Day .................. 24 

TABLE 4-3: Application of Added Control Measures to Attain 24-Hour PM,, NAAQS at 

Gilbert Site on April 9, 1995 Design Day ....................... 25 

TABLE 4-4: Application of Added Control Measures to Attain 24-Hour PM,, NAAQS at 

Maryvale Site on April 9,1995 Design Day ..................... 26 

TABLE 4-5: Application of Added Control Measures to Attain 24-Hour PM,, NAAQS at 

West Chandler Site on April 9, 1995 Design Day ................. 27 

LIST OF APPENDICES 

A Technical Support Document 

B ENSR Report - Evaluation of Fugitive Dust Control in the Marico~a County PM,, 

Nonattainment Area, dated March 1997 

C Text of the Maricopa County Rule, Rule 200 Permit Requirements; 

Text of the Maricopa County Rule, 310 Open Fugitive Dust Sources; 

Maricopa County Rule 310 Completeness Checklist; and 

Maricopa County Rule 310 Public Hearing Documentation 

D Correspondence 

E Best Available Control Measures (BACM) Commitments and Documentation 

F Public Hearing Documentation 

G Responsiveness Summary and Copies of Comments 
EXECUTIVE SUMMARY 

The U. S. Environmental Protection Agency (EPA) designated the portion of Maricopa County 

that encompasses the greater Phoenix Metropolitan Area as a Moderate PM,, Nonattainment Area 

by operation of law under the 1990 Clean Air Act Amendments. The Moderate Area Plan 

developed by the Maricopa Association of Governments (MAG), the Arizona Department of 

Environmental Quality (ADEQ), Maricopa County Environmental Services (MCESD) and the 

Arizona Department of Transportation (ADOT) and submitted to EPA November 15, 1991, did 

not demonstrate attainment of the PM,, NAAQS by the Clean Air Act (CAA) deadline of 

December 31, 1994. EPA, however, deemed the Plan "incomplete", which afforded Arizona time 

to develop additional control measures that would address the sho~tfall in PM,, emission 

reductions. Even with the additional control measures, the Moderate Area Plan still fell short of 

demonstrating attainment of the PM,, NAAQS. 

In accordance with Section 1880 of the CAA, the deadline for the State to demonstrate attainment 

of the PM,, National Ambient Air Quality Standards (NAAQS) for this area was December 31, 

1994; however, Arizona demonstrated to EPA that it was impracticable for this area to attain the 

annual PM,, NAAQS by the specified deadline. No demonstration was made for the24-hour 

PM,, NAAQS because at that time an accurate assessment of the causes of the historical 

exceedances was not possible. The sources of the PM,, emissions that caused the exceedances 

appeared to be local in nature, and site-specific emissions data were not available for those days. 

In order to address the specific causes of and necessary controls for 24-hour exceedances, the 

Phoenix PM,, Microscale Field Study (Microscale Study) was designed in 1994 and conducted 

throughout 1995. 

On July 28, 1994, EPA proposed to approve the Moderate Area Plan and published its final 

approval of the Moderate Area Plan on April 10, 1995. In response, the Arizona Center for Law 

in the Public Interest (ACLPI) formally filed suit on the Moderate Area Plan on April 27, 1995. 

Amidst the discussions and litigation concerning the approvability of the Plan, EPA reclassified 

the Maricopa County PM,, Nonattainment Area to serious effective June 10, 1996, based upon 

its finding the area failed to attain the PM,, NAAQS by the December 31, 1994, deadline. Later, 

on May 14, 1996, the Court of Appeals for the Ninth Circuit found that the Moderate Area Plan 

failed to address the 24-hour PM,, standard as required by the CAA [Ober v.EPA, 84 F3d 304 

(9th Cir. 1996)l. As a result, the Court mandated that EPA require "the State to submit a separate 

demonstration of the implementation of all 'reasonably available control measures' targeting the 

24-hour standard violations; attainment and 'reasonable further progress' for the 24-hour 

standard. " 

In September 1996, in response to the Court's mandate, EPA and ADEQ agreed that ADEQ 

would submit a "Limited" Serious Area PM,, Plan to EPA by April 18, 1997 and a "Full" 

ADEQ ES-1 May 7,1997 
Serious Area Plan by December 10, 1997. The Microscale Study became the basis for this 

"Limited" Plan. The "Limited* Plan deadline was subsequently revised to May 9, 1997 (see 

Appendix D, Marcus, 1996 and 1997). The "Limited" Plan is required to: 

Address exceedances of the 24-hour NAAQS that occurred at five moniton in 1995 

during the PMlo Microscale Study. (East Chandler, West Chandler, Gilbert, 

Maryvale and Salt River); 

Document the development of emissions inventories and air quality modeling tl, 

quantify contributions of sources to the exceedances; 

Identify, document and evaluate all RACM, Best Available Control Measures 

(BACM) and other controls to reduce emissions from the contributing sources; 

Demonstrate attainment of the 24-hour standard by application of RACM, BACM 

and other controls as soon as practicable but no later than December 31, 2001; 

The contained provisions for quantitative milestones to measure reasonable further 

progress, and 

@ Include fully adopted and enforceable control measures with schedules for their 

implementation. 

Five sites were selected to characterize effects on PMlo concentrations from sources of fugitive 

dust emissions that are typical and located throughout the Maricopa Coun' PMlo Nonattainment 

Area. One site, East Chandler, was dropped from the study due to lack of confidence in the 

emissions inventory data. Modeling and data review of the results from the Microscale Study 

indicated that local fugitive PM,, emissions from sources such as earthmoving and windblown 

emissions from such sources as unpaved parking lots, agricultural areas, construction sites, 

disturbed open areas, and industrial sites are the predominate causes of exceedances of the 24-hour 

standard in Maricopa County. 

Maricopa County's Rule 310 is applicable to the fugitive emission sources addressed in the 

Microscale Study. Strengthening the enforcement of Rule 3 10 would be the logical first step in the 

consideration of potential control measures. Additional RACM and BACM that address fugitive 

PM,, emissions must also be evaluated. The control measures that are identified to demonstrate 

attainment of the 24-hour standard at the microscale sites would be applied to similar sources 

throughout the Maricopa County PM,, Nonattainment Area to achieve compliance for the entire 

region. 

Proposed BACM to be adopted and implemented regionally to reduce emissions from sources e( contributing to violations of 24-hour PMlo NAAQS at the four microscale sites are: 

May 7,1997 
Improvements to the Maricopa County Dust Control Plan checklist and guidelines to 

ensure that dust control is implemented at all times, even on weekends and prior to high 

wind conditions. 

Increased MCESD inspection resources, to improve enforcement of Rule 3 10 requirements 

for vacant areas and unpaved roads and on weekends, as well as for earthmoving projects. 

Development of a pilot program by MCESD for weekend inspection of fugitive dust 

sources. 

Revision of MCESD's "Guideline for Earthmoving Inspection Checklistn to include 

additional detail more closely following the revised Dust Control Plan. The standard 

operating procedure, Air Pollution Inspection Procedures has been revised to instruct 

stationary source inspectors to review a source's dust control plan and inspect the fugitive 

dust sources to determine its compliance with Rule 3 10. 

Designation of a staff person by MCESD to interact with cities, towns and other agencies 

and be the lead coordinator for dust control. MCESD has developed a Rule 3 10 training 

package. MCESD will initially offer training at least once per quarter, but may revise that 

schedule based.upon demand. Training will begin in June 1997. 

Participation by MCESD in a regional program with participation from the cities and other 

agencies within Maricopa County to identify ways to use existing City ordinances to 

increase enforcement on vacant lands and unpaved parking areas. This group will also 

work with Natural Resources Conservation Service (NRCS) to develop feasible control 

i measures for agriculture. 5 

Development of a protocol to implement improved coordination among the cities and 

MCESD adopted by cities in Maricopa County to improve dust control. The format of the 

agreement is a resolution adopted by the respective city councils. 

Pursuit of a Memorandum of Agreement by the NRCS, MCESD and ADEQ to establish 

a formal process to address fugitive dust on agricultural land while refining the roles, 

I objectives, and schedule of this partnering process. 

In summary, proposed BACM strategies provide for attainment of the 24-hour PM,, NAAQS at 

two of the four sites evaluated, Maryvale and Salt River site. The other two sites, West Chandler 16 and Gilbert, were affected by significant contributions from agricultural sources and unpaved 

parking areas. Adequate control mechanisms to address these sources are currently under 

development. 

May 7, 1997 
3.0 RESULTS OF MICROSCACE STUDY 

ADEQ conducted air quality modeling for the 1995 exc-m &ys shown in Table 3-1 ~hh 

modeling process is described as follows: 

Defining a microscale modeling domain for each monitoring site. This domain was 

a rectangular geographic area that included all PM, emissions that were expected 

to have an identifiable impact. 

Characterizing the activities and diurnal profile of each source within each 

modeling domain. 

Estimating PM,, emissions from all sources within each microscale modeling 

domain. 

Using a "screening* air quality model to estimate ambient PM,, impacts at the 

monitor from the sources in the modeling domain. 

Refining the definition of the modeling domain from examination of the screening 

results. This refinement frequently decreased the size of the domain. 

Evaluating and validating model performance for the design cases by comparing 

the modeled results with the monitored 24-hour PM,, concentration. 

Selecting a subset of days for each monitoring site to serve as "design cases* for 

evaluation of additional control measures to reduce PM,, concentrations. 

Reviewing the modeling results for the design cases to identify the location within 

each microscale modeling doinain where the modeled PM,, concentration was the 

highest on each design day. The demonstration of attainment of the 24-hour PM,, 

standard requires that control measures be implemented to reduce the modeled 

concentration at this maximum concentration location to or below the level of the 

standard. This location was not always the location of the PM,, monitor. 

Therefore, the maximum value was sometimes higher than the monitored value. 

Determining, from the modeling, the contributions of individual source categories 

to the maximum concentrations. 

May 7, 1997 
3.0 RESULTS OF MICROSCACE STUDY 

ADEQ conducted air quality modeling for the 1995 exme shown in Table 3-1. his 

modeling process is described as follows: 

Defining a microscale modeling domain for each monitoring site. This domain was 

a rectangular geographic area that included all PM, emissions that were expected 

to have an identifiable impact. 

Characterizing the activities and diurnal profile of each source within each 

modeling domain. 

Estimating PM,, emissions from all sources within each microscale modeling 

domain. 

Using a "screening" air quality model to estimate ambient PM,, impacts at the 

monitor from the sources in the modeling domain. 

Refining the definition of the modeling domain from examination of the screening 

results. This refrnement frequently decreased the size of the domain. 

Evaluating and validating model performance for the design cases by comparing 

the modeled results with the monitored 24-hour PM,, concentration. 

Selecting a subset of days for each monitoring site to serve as "design cases" for 

evaluation of additional control measures to reduce PM,, concentrations. 

Reviewing the modeling results for the design cases to identify the location within 

each microscale modeling doinain where the modeled PM,, concentration was the 

highest on each design day. The demonstration of attainment of the 24-hour PMlo 

standard requires that control measures be implemented to reduce the modeled 

concentration at this maximum concentration location to or below the level of the 

standard. This location was not always the location of the PM1, monitor. 

Therefore, the maximum value was sometimes higher than the monitored value. 

Determining, from the modeling, the contributions of individual source categories 

to the maximum concentrations. 

ADEQ 14 May 7,1997 
TABLE 3-1 

24-Hour PM,, Exceedances in 1995 

I West Chandler I 4/9/95 I 462.5 1 

East Chandler 

12/11/95 . . . . . . . . , . . . . . . . . . . . . . . , , . . . . . , . ., , . . . . . . . . . . . . . . . . . , . . . . . , . . . . , . , . ::: ..: :; ..,: :.> :..:...:.:.:. .::.....:.,. .. ., . . . . . ... .. . . ... . , . ......... 

156.5 ,, . . . . , . , ........ :. ... ...................... ...........,....... >.....,... ................................. :. . :.:.:.:: ... :.::,:.,.:::<: ,,:: :;j :.::?<::;:. ........................ ...................... :::: .''' . ... .:+ :... ' .. .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , , . . . . . . . .::. . .. . . . . . . .....,,..,. , .,.,.........,., .., , ..,:.*::::: . . . . ..................... . . . . . . . . . ..:..:. . ..'.'. . ....................................... . . . . . . .: . :: . ..:. ...... . . . . . . . . . . . . . . , .. . , . . , . , . , , , ,.. . . .. < ... . . . . . . . . . . . , . . . . , . , , . . . . , . . ... . . . , . . . . . . , . ;,. . . . , , . , . .... ..... : , .. . . . . . . . . . . . . . . ,.. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...... . . . . . , . , 

;,, , E*ee&&e,,&$s &t~&.~&m~*.j,,'& ,wjj&i,@&,&'&g;;+,,;;, &: s$&;$&,iw a?&$:;.,:;:,;:;::;;;;;;;, :, ::;;;;;: :::y :;::; :,:;.;y: : .; ;:;.;: :; 

NOTE: The 24-hour PM,, NAAQS is 150 pg/m3- 

6/28/95* 

7/30/95* 

Salt River 

ADEQ 15 May 7,1997 

160.0 

251.7 

8/3/95 

61 12/95 

7120195 * 

7/26/95 

8/1/95 

169.3 

165.4 

166.3 

165.2 
For a more detailed discussion of the methodology of how sources were inventoried and 

apportioned for the four sites, please refer to the Technical Support Document, 

Appendix A. 

3.1 Air Quality Modeling Results 

This section presents the modeling results and identifies control measures that could be 

implemented to reduce the modeled concentrations to or below the 150 pg/m3 level of the 24-hour 

PMlo NAAQS. 

ADEQ selected the following design cases: 

October 16, 1995, at the Salt River monitoring site; and 

April 9, 1995, at the Gilbert, Maryvale and West Chandler monitoring sites. 

Tables 3-2 through 3-5 present the contributions of fugitive dust emission source categories to the 

maximum modeled concentration within the modeling domains for each of the design cases along 

with ADEQ's estimate of the PM,, background concentration. The tables also indicate the 

estimated PMlo emission control efficiency for each source category on the design day. 

The largest contribution at the Salt River site on October 16, 1995, was from earth moving 

activities during remediation work at the 19th Avenue Landfill. ADEQ's review of video tapes 

of operations at the landfill indicated that, although water was applied during the earthmoving 

activities, the amount was not adequate to wet the soil to the depth of cuts, so emissions from 

travel of scrapers over the freshly exposed surface was essentially uncontrolled. 

The April 9, 1995, design day was a Sunday, and most of the PMlo emissions were caused by 

wind action on exposed, disturbed surfaces, when active operations were not taking place. The 

greatest contribution of emissions at the Gilbert site were windblown dust from agricultural aprons 

(the land next to the agricultural fields generally used for travel of farm equipment), and unpaved 

parking and disturbed areas. At Maryvale, windblown dust from a city park construction area 

dominated concentrations. Windblown dust from an agricultural field was the greatest contributor 

at the west -Chandler site, along with windblown dust from nearby road construction, vacant land 

and agricultural aprons. 

3.1.1. East Chandler Site 

Exceedances occurred on June 28 and July 30, 1995. No reliable information on emissions sources 

was found and no further evaluation was conducted for those days. 

ADEQ 16 May 7,1997 
TABLE 3-2 

Air Quality Modeling Results for Maximum Concentration at Salt River Site 

on October 16,1995, Design Day 

ADEQ 17 May 7, 1997 

Contribution to PM,, 

Concentration 

(dm3) 

10.4 

2.4 

2.7 

1 .O 

50.8 

3.6 

0.3 

5.1 

0.1 

12.6 

89.0 

78.3 

167.3 

Source Category 

Estimated PM,, 

Control Efficiency on 

Design Day 

Industrial haul roads 

Industrial yards 

Surface mining 

Other industrial activities 

Earth moving 

Paved roads 

Trackout 

Unpaved roads 

Paved parking lots 

Unpaved parking areas 

Total 

Background 

Total with Background 

50 % 

50 % 

10 % 

50 % 

10% 

0% 

95 % 

0% 

0% 

0% 
Air Quality Modelin 

Source Category 

Agricultural aprons 

Disturbed areas 

Unpaved parking areas 

Unpaved roads 

Paved roads 

Total 

Background 

Total with Background 

TABLE 3-3 

: Results for Maximum Concentration at GiIbert Site 

on April 9,1995, Design Day 

Estimated PMlo Control Contribution to PM,, 

Efficiency on Design Day . Confearstion Ipg/m? 

0% 55.6 

0% 14.2 

0% 51.3 

TABLE 3-4 

Air Quality Modeling Results for Maximum Concentration at Maryvale Site 

on April 9, 1995, Design Day 

Source Category 

Disturbed cleared areas (city 

park construction) 

Paved roads 

- 

Estimated PMlo Control Contribution to PM, 

Efficiency on Design Day Concentration (Icg/m3) 

0% 414.3 

0% 2.6 

Unpaved roads 

Total 

0% 0.1 

417.0 

Background 

May 7,1997 

90.0 

Total with Background 507.0 
TABLE 3-5 

Air Quality Modeling Results for Maximum Concentration at West Chandler Site 

on April 9, 1995, Design Day 

May 7,1997 

Contribution to PM,, 

Concentration - 

Source Category @g/m3) 

Estimated PM,, 

Control Efficiency on 

Design Day 

Agricultural fields 

Vacant land . Agricultural aprons 

Road construction 

Paved roads 

Unpaved roads 

Total 

Background 

Total with Background > 

0% 

0% 

0% 

0% 

0% 

0% 

194.7 

28.1 

21.7 

68.7 

0.2 

- 

0.5 

313.9 

80.0 

393.9