UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document

for

EPA’s Rulemaking

for the

Arizona State Implementation Plan

Agricultural Best Management Practices Definitions Rules

Agricultural PM10 General Permits Rules

Appendix 2. Test Methods and Protocols

December 19, 2016
1

RULE IDENTIFICATION 

Agency Arizona Department of Environmental Quality (ADEQ)

SIP-Approved 

Rules

Arizona Administrative Code (AAC) R18-2-610, “Definitions for R18-2-611”; and

AAC R18-2-611, “Agricultural PM10 General Permit: Maricopa PM10 Nonattainment Area”

Effective: May 12, 2000.

Submitted: July 11, 2000.

EPA Approved: October 11, 2001 (66 FR 51869).

Appendix 2, Test Methods and Protocols

Effective: October 3, 2005.

Submitted: July 28, 2011.

EPA Approved: September 23, 2014 (79 FR 56655).

Subject of this 

TSD

AAC R18-2-610, “Definitions for R18-2-610.01, R18-2-610.02, and R18-2-610.03”; 

AAC R18-2-610.3, “Agricultural PM General Permit for Crop Operations; Pinal County PM 

Nonattainment Area”; 

AAC R18-2-612, “Definitions for R18-2-612.01”;

AAC R18-2-612.01, “Agricultural PM General Permit for Irrigation Districts; PM Nonattainment 

Areas Designated After June 1, 2009”; and

AAC Appendix 2, “Test Methods and Protocols.”

Effective: July 2, 2015

Submitted: December 21, 2015

Completeness 

Finding

Determination of completeness letter: March 21, 2016

BACKGROUND 

The current SIP-approved versions of AAC 18-2-610, “Definitions for R18-2-611” and AAC R18-2-

611, “Agricultural PM10 General Permit: Maricopa PM10 Nonattainment Area,” established definitions 

of Agricultural Best Management Practices (AgBMPs) and an agricultural general permit rule for the 

Maricopa PM10 Nonattainment Area. ADEQ’s December 21, 2015 submittal includes new rule AAC 

R18-2-610, “Definitions for R18-2-610.01, R18-2-610.02, and R18-2-610.03.” This new rule does not 

supersede AAC 18-2-610 “Definitions for R18-2-611,” which remains in the SIP. If the new rule is 

approved, there will be two rules in the SIP with the same number but different titles.1

The Arizona AgBMP program includes an AgBMP Committee, as established in Arizona Revised 

Statute (ARS) 49-457,

2 and agricultural general permit (general permit) rules adopted by the AgBMP

Committee, specifying best management practices for regulated agricultural activities to reduce PM10

emissions.3

 

1 We note that AAC R18-2-611, “Agricultural PM10 General Permit: Maricopa PM10 Nonattainment Area” also remains in 

the SIP and will not be superseded by a rule with the same number in the December 21, 2015 submittal.

2 ARS 49-457 Agricultural best management practices (AgBMP) committee; members; powers; permits; enforcement; preemption; definitions. ARS 49-457 was approved into the SIP on June 29, 1999 (64 FR 34726). On April 10, 2015, the 

AgBMP committee revised ARS 49-457. ADEQ submitted the revised statute to EPA on December 21, 2015. Among other 

things, the revised statute expanded the definition of “agricultural general permit” to include reducing PM10 emissions from 

activities of a dairy, a beef cattle feed lot, a poultry facility or a swine facility, including unpaved access connections, 

unpaved roads or feed lanes, animal waste handling and transporting, and arenas, corrals and pens. We are not taking action 

on submitted ARS 49-457 at this time.

3

Ibid. section H. 
2

The rules adopted by the AgBMP Committee to date apply to three categories of agricultural operations: 

Commercial Farms (Crops), Animal Operations, and Irrigation Districts. In each category, the 

Committee has adopted a “definitions” rule and “general permit” rules.

4

ADEQ submitted to the EPA for SIP approval only the AgBMP general permit rules for the West Pinal 

nonattainment area5and the definitions rules that apply these general permit rules. The submitted 

definitions rules also apply to general permit rules that were not submitted by ADEQ, including those 

for the “Maricopa County PM Nonattainment Areas,” “Moderate PM Nonattainment Areas designated 

after June 1, 2009, except Pinal County PM Nonattainment Area,” and the “Yuma PM10 Nonattainment 

Area.”

6

Collectively, we refer to the submitted rules evaluated in this TSD as “AgBMP” rules.

The previous SIP-approved version of “Appendix 2. Test Methods and Protocols” included test methods 

and protocols approved by the ADEQ and incorporated by reference as applicable requirements. The 

submitted revision to Appendix 2 adds test methods.

On May 6, 2010, ADEQ submitted amended rules AAC R18-2-610. “Definitions for R18-2-611” and 

AAC R18-2-611. “Agricultural PM10 General Permit; Maricopa PM10 Nonattainment Area and 

Maricopa County Portion of Area A.” On September 9, 2010, EPA proposed a simultaneous limited 

approval and limited disapproval of these rules because they strengthened the SIP but they did not fully 

meet the CAA requirements for enforceable Best Available Control Measures (BACM) in the Maricopa 

NAA.

7 ADEQ withdrew the amended rules on April 26, 2014.

In this TSD, we discuss a subset of the rules that ADEQ submitted to EPA on December 21, 2015.8 They 

are as follows: AAC R18-2-610. “Definitions for R18-2-610.01, R18-2-610.02, and R18-2-610.03”;

AAC R18-2-610.3, “Agricultural PM General Permit for Crop Operations; Pinal County PM 

Nonattainment Area”; AAC R18-2-612, “Definitions for R18-2-612.01”; 

AAC R18-2-612.01, “Agricultural PM General Permit for Irrigation Districts; PM Nonattainment Areas 

Designated After June 1, 2009”; and AAC Appendix 2, “Test Methods and Protocols.”

RULE SUMMARY

R18-2-610, Definitions for R18-2-610.01, R18-2-610.02, and R18-2-610.03 – ADEQ submitted this

new rule to EPA for SIP approval. New rule R18-2-610 provides definitions for general permit rules 

 

4 For example, there is one definitions rule (R18-2-610) that applies to three different agricultural general permit rules (R18-

2-610.01, R18-2-610.02, and R18-2-610.03). 

5 ADEQ submitted the following general permit rules for SIP approval: R18-2-610.03. “Agricultural PM General Permit for 

Crop Operations: Pinal County PM Nonattainment Area,” R18-2-611.03. “Agricultural PM General Permit for Animal 

Operations: Pinal County PM Nonattainment Area,” and R18-2-612.01. “Agricultural PM General Permit For Irrigation 

Districts: PM Nonattainment Areas Designated After June 1, 2009.”

6 ADEQ adopted but did not include in this submittal the following general permit rules: R18-610.01, R18-2-610.02, R18-2-

611.01, R18-2-611.02, R18-2-613 and R18-2-613.01.

7 Proposed simultaneous limited approval and disapproval of AAC R18-2-610 and AAC R18-2-611: September 9, 2010 (75 

FR 54806). Maricopa County Serious Area PM10 Nonattainment Area - Agricultural Best Management Practices: Revisions 

to Article 6. R18-2-610 and R18-2-611. Effective: November 14, 2007. Submitted: May 6, 2010. Withdrawn: April 25, 2014.

8 This TSD does not address submitted rules AAC R18-2-611, “Definitions for R18-2-611.01,” and AAC R18-2-611.03,

“Agricultural PM General Permit for Animal Operations; Pinal County PM Nonattainment Area.”
3

R18-2-610.01, R18-2-610.02, and R18-2-610.03. Of those general permit rules, the ADEQ has, in this 

submittal, included only R18-2-610.03, "Agricultural PM General Permit for Crop Operations: Pinal 

County PM Nonattainment Area” for SIP approval.

9

New rule R18-2-610 contains 65 definitions, including 29 AgBMP definitions. AgBMP definitions in 

new rule R18-2-610 include specific standards or testing requirements that the commercial farmer 

(farmer) must meet when implementing an AgBMP selected for compliance with the general permit 

rule. For example, the AgBMP definition of “conservation tillage” is “a tillage system that reduces a 

minimum of three tillage operations. This system reduces soil and water loss by planting into existing 

plant stubble on the fields after harvest as well as managing the stubble to that it remains intact during 

the planting season.” See R18-2-610(13). “Cover crop” is defined as “establishing cover crops that 

maintain a minimum of 60 percent ground cover...Compliance shall be determined by the Line Transect 

Test Method, NRCS National Agronomy Manual, Subpart 503.51, Estimating Crop Residue Cover, 

amended through February 2011 (and no future editions).” See R18-2-610(14). The rule defines “tillage 

operation” as “an agricultural operation that mechanically manipulates the soil for the enhancement of 

crop production. Examples include discing or bedding. A pass through the field may be a subset of a 

tillage operation.” See R18-2-610(58).

R18-2-610.03, Agricultural PM General Permit for Crop Operations: Pinal County PM 

Nonattainment area – This new rule requires a commercial farmer (“farmer”) to complete a BMP 

Program General Permit Record Form (BMP Form), demonstrating compliance with the rule and 

specifying the BMPs selected for tillage, ground operations and harvest, cropland, noncropland, 

commercial farm roads, and significant earth moving activities, and any BMPs selected for “high risk” 

days, as predicted by the Pinal County Dust Control Forecast (section C). The rule creates six categories 

of BMPs: B.1. Tillage; B.2. Ground Operations and Harvest; B.3. Noncropland; B.4. Commercial Farm 

Roads; B.5. Cropland; and, B.6. Significant Agricultural Earth Moving Activities. Each category 

contains six to twelve BMP options.

This rule requires a farmer who engages in a regulated agricultural activity (as defined in R18-2-

610(45))10 to implement at least one BMP from each of the Tillage, Ground Operations and Harvest, 

Noncropland, Commercial Farm Roads, and Significant Agricultural Earth Moving Activities

categories. The farmer must implement two BMPs in the Cropland category. See section B.

As required by Section A of Rule R18-2-610.03, farmers must ensure implementation of BMPs as 

described in sections B.1(b), B.2(b), B.3(b), B.4(b) and B.5 (b) on the day before and during the day that 

is forecast to be high risk for dust generation (see R18-2-610(18)).

Described in sections C, D, E, F, G, and K, the administrative requirements of R18-2-610.03 include the 

following:

 

9 SIP-approved R18-2-610, “Definitions for 18-2-611,” remains in the applicable SIP and applies to SIP-approved R18-2-611,

“Agricultural PM10 General Permit: Maricopa PM10 Nonattainment Area”. 66 FR 51869 (October 11, 2001).

10 The definition R18-2-610(45) refers to ARS 49-457(P)(1)(a) through (P)(1)(d), as revised July 24, 2015. We believe this is 

an error, as the definition for “regulated agricultural activities” is in section P.5. of the revised statute. Section R18-2-610(45)

should be corrected to provide correct citation. 
4

1. From and after December 31, 2015, a farmer who engages in a regulated agricultural activity 

must complete a BMP Form. Thereafter, the farmer must complete a new BMP Form every year 

by March 31. The BMP Form must be provided to the Director11 within two business days of 

notice to the farmer. The BMP Form must include the name of the farmer, signature and date 

signed; the mailing or physical address of the farm; the BMPs selected for tillage, ground 

operations and harvest, cropland, noncropland, commercial farm roads, and significant earth 

moving activities. It must also include any additional BMPs selected for high risk days, as 

predicted by the Pinal County Dust Control Forecast. See section C.

2. Beginning in 2017, and no more than once every subsequent three years, the ADEQ must

provide the farmer with a BMP Program 3-year Survey. The farmer must complete the Survey 

with data from the prior year, and submit it to the Arizona Department of Agriculture (ADA) by 

January 31, 2018, and every three years thereafter. The ADA will compile the data in a way that 

does not refer to the operator’s name, and send the aggregated data to the Department.

12 On the 

survey, the farmer must provide the name, business address, and phone number of the person 

responsible for the preparation and implementation of the BMPs, the signature of the farmer and 

date the form was signed, the acreage of each crop type planted or growing; the total miles of 

farm roads; the total acreage of noncropland; and the BMPs (for all days and for high risk days) 

selected for the farm. See section D.

3. The farmer is required to record changes to the BMPs on the BMP Form and to keep the form 

onsite and available to the Director within two business days of notice. See section E.

4. New BMPs can be developed and submitted to the Committee if they are proven effective 

through on-farm demonstration trials to the Committee. They will not become effective unless 

submitted to EPA for SIP approval, per ARS 49-457(L).

13 See section F.14

5. The farmer must keep a record demonstrating compliance with the rule for three years, including 

a copy of the complete BMP Form to confirm implementation of each BMP. See section G.

6. A farmer who is not in compliance with the rule is subject to provisions in ARS 49-457(I), (J) 

and (K). See section K.15

R18-2-612 Definitions for R18-2-612.01– ADEQ submitted this new rule for SIP-approval that 

provides 33 definitions for new rule R18-2-612.01. 

 

11 For purposes of this TSD, we consider that “Director” refers to the Director of the Arizona Department of Environmental 

Quality (ADEQ).

12 For purposes of this TSD, we consider that “Department” refers to the ADEQ.

13 49-457 (L): “The committee may periodically reexamine, evaluate and modify best management practices. Any approved 

modifications shall be submitted to the United States Environmental Protection Agency as a revision to the applicable 

implementation plan.” 64 FR 34726 (June 26, 1999).

14 Rule 18-2-610.03 section F: “A person may develop different practices to control PM emissions not contained in 

subsections (B)(1) through (B)(6) and may submit such practices that are proven effective through on-farm demonstration 

trials to the Committee. The proposed new practices shall not become effective unless submitted as described in A.R.S. §49-

457(L).”

15 Rule 18-2-610.03 section K. If a person fails to comply with the plan submitted pursuant to subsection J of this section, the 

director may revoke the agricultural general permit for that person and require that the person obtain an individual permit 

pursuant to section 49-426. A revocation becomes effective after the director has provided the person with notice and an 

opportunity for a hearing pursuant to title 41, chapter 6, article 10.
5

R18-2-612.01 Agricultural PM General Permit for Irrigation Districts; PM Nonattainment Areas 

Designated After June 1, 2009 – ADEQ submitted this new rule for SIP approval. It requires an 

irrigation district within a PM nonattainment area to implement at least one BMP from each specified 

category to reduce PM emissions. The rule divides BMPs into three categories: 1. “Unpaved operation 

and maintenance roads” (13 BMP options), 2. “Canals” (five BMP options) and 3. “Unpaved utility 

access roads” (13 BMP options). Some of the BMPs are similar to those listed for unpaved roads and 

unpaved access areas in Rule 18-2-610, such as “Access restriction,” “Apply and maintain aggregate 

cover,” “Install and maintain a track-out control system,” and “Apply and maintain synthetic particulate 

suppressant.” However, BMPs specific to the irrigation district have been added, including “Apply and 

maintain water before, during and after major and minor earth moving activities,” “dredge canals while 

muck or debris is still wet,” and “weed management.” For irrigation districts, the “Reduce vehicle 

speed” BMP sets a maximum speed of 25 mph, whereas, the “Reduce vehicle speed” BMP for farming 

operations is 15 mph. 

The administrative provisions of Rule R18-2-612.01 require the following actions:

1. From and after December 31, 2015, an irrigation district engaged in a regulated agricultural 

activity must complete a BMP Form. After that, the operator must complete a new BMP Form by 

March 31 every year. The BMP Form must be provided to the Director within two business days 

of notice to the irrigation district. The BMP Form must include the name, business address of the 

irrigation district representative responsible for the preparation and implementation of the BMPs; 

the signature of this representative and the date the form was signed; and the BMPs selected for 

unpaved operation and utility roads, canals, and unpaved utility access roads. See section B.

2. Beginning in 2017, and no more than once every subsequent three years, the Director, in 

conjunction with the ADA, must provide the irrigation district with a BMP Program 3-year 

Survey. The irrigation district must complete the survey with data from the prior year and submit 

it to the ADA by January 31, 2018, and every three years thereafter. The ADA must compile the 

submitted survey data and submit it to the Department. In the survey, the operator must provide 

the name, business address, and phone number of the irrigation district representative responsible 

for the preparation and implementation of the BMPs, the signature of the irrigation district 

representative and date the form was signed, the total miles of canals that the irrigation district 

controls; the total miles of unpaved operation and maintenance roads; the total miles of the 

unpaved utility access roads; and the BMPs selected for unpaved operation and utility roads, 

canals, and unpaved utility access roads. 

3. Records of changes to the selected BMPs must be written on the BMP Form, kept onsite by the 

irrigation district representative, and must be kept on site and made available for review by the 

Director within two business days of notice. The irrigation must keep records demonstrating 

compliance with the rule for three years. Records include a copy of the BMP Form to confirm 

implementation of each BMP. See sections D and F.

4. An irrigation district may develop different practices not included in subsections (A)(1), (A)(2), 

or (A)(3) and may submit practices that are proven effective through in-district trials. They will 

not become effective unless submitted to EPA for SIP approval (per ARS 49-457(L)). See 

section E.
6

5. An irrigation district that is not in compliance with the rule is subject to provisions in ARS 49-

457(I), (J), and (K). See section J. 

These administrative provisions are analogous to those found in Rule R18-2-610.03.

Appendix 2. Test Methods and Protocols (“Appendix 2”) – ADEQ submitted for SIP-approval a 

revision of SIP-approved Appendix 2 to relabel section numbers (1 through 11) to letters (A through K)

and to add sections L and M. As confirmed by ADEQ, Section L’s reference to 40 CFR 51.128 is a 

typographical error; the intended reference is to 40 CFR 52.128.16 The Silt Content Test Method, as 

described in new section M, is used to estimate the silt content of trafficked parts of commercial farm 

roads. Vehicle traffic on roads with higher silt content release greater levels of fine dust particles.

EVALUATION CRITERIA 

The following criteria were used to evaluate the submitted rules. 

1. Enforceability - The Bluebook (Issues Relating to VOC Regulation Cutpoints, Deficiencies, and 

Deviations, EPA, May 25, 1988) and the Little Bluebook (Guidance Document for Correcting Common 

VOC & Other Rule Deficiencies, EPA Region 9, August 21, 2001) were used to help evaluate 

compliance with the CAA §110(a)(2)(A) requirement for enforceability in control measures and other 

SIP limitations. 

2. Stringency – Nonattainment areas are required to demonstrate reasonably available control 

measures (RACM). CAA Section 172(c)(1) requires that each attainment plan “provide for the 

implementation of all reasonably available control measures 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), and shall provide for the attainment of the 

national primary ambient air quality standards.” RACM findings are generally made in context of an 

overall attainment demonstration. Our stringency evaluation includes primarily a comparison of these 

AgBMP provisions with existing Arizona SIP provisions and other state’s rules that apply to similar 

sources. 

3. SIP Relaxation - CAA §110(l) prohibits EPA from approving any SIP revision that would 

interfere with any applicable requirement concerning attainment and reasonable further progress (RFP) 

or any other applicable requirement of the CAA. In addition, CAA §193 prohibits the modification of 

any SIP-approved control requirement in effect before November 15, 1990, in a nonattainment area.

EPA EVALUATION 

A summary of our evaluation of the three criteria follows.

1. Enforceability Evaluation - To help ensure enforceability, the rule requirements and 

applicability are clear, and the recordkeeping, reporting and other provisions sufficiently ensure that 

 

16 See April 8, 2016 email correspondence between H. Haggerty, ADEQ and N. Levin, EPA re: Appendix 2.
7

affected sources and regulators can evaluate and determine compliance with AgBMP rules consistently

and with replicable result. 

The definition rules R18-2-610 and R18-2-612 contain BMP and related definitions that are clear and 

specific for the implementation of the source-specific General Permit Rules R18-2-610.03 and R18-2-

612.01, respectively.

Examples in R18-2-610 include:

 “Combining tractor operations” means reducing soil compaction and a minimum of one 

tillage or ground operation across a commercial farm using a tractor, implement, 

harvester, or other farming support vehicle to perform two or more tillage, cultivation, 

planting, or harvesting operations at the same time. If “Equipment modification” is also 

chosen as a BMP, and uses the same practices as described in this BMP, this action is 

considered one BMP. 

 “Cover Crop” means establishing cover crops that maintain a minimum of 60 percent 

ground cover...Compliance shall be determined by the Line Transect Test Method, 

NRCS National Agronomy Manual, Subpart 502.51, Estimating Crop Residue Cover, 

amended through February 2011 (and no future editions).

 “Conservation Tillage” means a tillage system that reduces a minimum of three tillage 

operations. This system reduces soil and water loss by planting into existing plant stubble 

on the field after harvest as well as managing stubble so that it remains intake during the 

planting season.

 “Fallow Field” means an area of land that is routinely cultivated, planted and harvested 

and is unplanted for one or more growing seasons or planting cycles, but is intended to be 

placed back in agricultural production. 

 “Harvest” means the time after planting up through harvest, including gathering mature 

crops from a commercial farm, as well as all actions taken immediately after crop 

removal, such as cooling, sorting, cleaning, and packing.”

 “Limited tillage activity means performing no tillage operations on a day identified by 

the Maricopa or Pinal County Dust Control Forecast to be high risk for dust generation.”

Examples in R18-2-612 include:

 "Apply and maintain synthetic or natural particulate suppressant" means reducing PM 

emissions and wind erosion by providing a stabilized soil surface with organic material, 

such as muck, animal waste or biosolids, or with a manufactured product such as 

lignosulfate, calcium chloride, magnesium chloride, and emulsion of a petroleum 

product, an enzyme product, or polyacrylamide.

 “Dredge canals” means reducing PM emissions by mechanically removing much, debris, 

and other foreign objects from canals while material is still wet or damp. 

 “Minor earth moving activities” means the mechanical movement of earth materials to 

repair and maintain the existing configuration, location, bank slopes, or inclines of canals. 

Rules R18-2-610.03 and R18-2-612.01 contain administrative requirements for farmers, operators, and 

irrigation districts. These requirements are clear, specific and include compliance dates, are similar for 

all operators, and include the annual obligation to complete a BMP Form demonstrating compliance 

with the rules, and the requirement to make the form available to the State within two days of notice. 

Every three years, starting in 2017, farmers, operators, and irrigation districts are required to complete 
8

and submit to the State a survey that includes the BMPs implemented the prior year, the acreage and/or 

mileage to which BMPs were applied, and the name, address, phone number and signature of the farmer, 

operator or responsible party. Records demonstrating compliance with the rules must be kept for three 

years. 

Appendix 2. Test Methods and Protocols section L adds the surface stabilization test method “Silt 

Content” from Appendix A(1)(B) of 40 CFR 52.128.17 Section M, “Silt Content Test Method,” has the 

same requirements as the SIP-approved Silt Content Test Method for Maricopa County (See Maricopa

County Air Pollution Control Regulations, Appendix C, Fugitive Dust Test Methods (section 2.1.2), 

amended March 26, 2008, approved by EPA on December 15, 2010 (72 FR 46564).

2. Stringency Evaluation – We are evaluating whether the AgBMP rules apply requirements 

consistent with other state’s rules.

Since 2001, other air quality districts have adopted rules for agricultural (crop) and unpaved irrigation 

road sources of PM. For example, EPA has approved the following rules into the SIP: 

 San Joaquin Valley Air Pollution Control District (SJVUAPCD or SJV) Rule 4550, 

Conservation Management Practices (CMPs), and List of Conservation Management 

Practices, 71 FR 7683, February 14, 2006.

18

 Imperial County APCD (ICAPCD) Rule 806 Conservation Management Practices 

(CMPs), 78 FR 23677, April 22, 2013.19 ICAPCD Rule 800, General Requirements for 

Control of Fine Particulate Matter, and Rule 805, Paved and Unpaved Roads 78 FR 

23677, April 22, 2013.20

 SJV Rule 8061 Paved and Unpaved Roads, Rule 8081 Agricultural Sources, and Rule 

8011 General Requirements, 71 FR 8461, February 17, 2006.

21

 South Coast Air Quality Management (SCAQMD) Rule 403 Fugitive Dust, 73 FR 12639, 

March 10, 2008.

SJV Rules 4550, 8011, 8061 and 8081; ICAPCD Rules 800, 805, and 806 and SCAQMD Rule 

403 were previously approved as satisfying the BACM requirements for the control of PM10. 

R18-2-610 (Crop Definitions) and R18-2-610.3 (Pinal Crops):

The Pinal Crops rule, SJV Rule 4550 and ICAPCD Rule 806 are menu-based rules. As such, 

they allow the farmer the flexibility to choose among a number of control measure options for 

each BMP (or CMP) category.

22 Table 1 provides a general comparison of these rules. The Pinal 

Crops rule regulates farms with 10 or more contiguous acres, while Imperial Rule 806 and SJV

Rule 4550 apply to farms of 40 and 100 or more acres, respectively. The Arizona AgBMP rules 

 

17 As discussed earlier, the AAR incorrectly refers to this section as 40 CFR 51.128. See April 8, 2016 email correspondence 

between H. Haggerty, ADEQ and N. Levin, EPA re: Appendix 2.

18 Adopted May 20, 2004; readopted August 19, 2004; submitted September 23, 2004 (71 FR 7683, February 14, 2006). EPA 

also approved a similar regulation into the SIP for the Great Valley Basin, Rule 502, adopted July 7, 2005; submitted October 

20, 2005.

19 Revised October 16, 2012, submitted November 7, 2012.

20 Rule 800 adopted October 10, 1994, revised October 16, 2012; Rules 805 adopted November 8, 2005, revised October 16, 

2012.

21 Adopted November 15, 2001; amended August 19, 2004.

22 For purposes of this document, the terms Best Management Practices (BMP) and Conservation Management Practice 

(CMP) are interchangeable. The rules in Arizona use the term BMP, while analogous rules in California use the term CMP.
9

generally regulate the same activities (tillage, harvest/ground operations, unpaved farm roads and 

noncropland (includes equipment areas)) on commercial farms as the SJV and Imperial CMP 

rules. The submitted Pinal Crops rule and the Imperial Rule 806 include mandatory windblown 

dust controls and offer an incentive to use conservation tillage. The submitted Crop Definitions

rule and Imperial Rule 806 include detailed BMP (or CMP) definitions for BMP (or CMP) 

implementation, whereas SJV Rule 4550 requires farmers to submit a CMP plan with CMP 

implementation details. The Arizona AgBMP rules require farmers to complete and submit a 

survey of BMP practices to the Arizona Department of Agriculture every three years. The 

SJVUAPCD rule requires each farmer to submit a CMP Plan to the APCD.

Table 1: Crop 

Operations

AAC R18-2-610 and 610.03 Imperial Rule 806 SJV Rule 4550

Applicability – farm 

size

10+ acres [610 (9)] 40+ acres [D.1] 100+ acres [2.0 and 4.1.1]

Control measures Implement at least one BMP 

per category, and two from 

section B(5)(a). [610.03 (A)

and (B)]. BMPs defined in 

610.

Implement at least one 

CMP per category [D.1]

Implement at least one CMP 

per category [5.0 and 6.2], 

CMP List

Crop BMP 

categories

Tillage, Ground operations 

and harvest; Cropland 

[610.03 (B) (1), (2), (5)]

Land preparationcultivation; Harvest 

activities; Cropland-other; 

Windblown dust control

Cropland- Land 

preparation/cultivation; 

Cropland-harvest; Croplandother [CMP List]

Noncropland, 

Unpaved road/area, 

significant earth 

moving BMP 

categories

Noncropland, Commercial 

Farm Roads (with additional

requirement for > 20 VDT 

2+axle vehicles);

Significant Agricultural Earth 

moving Activities [610.03 

(B)(3), (4), (6)]

Unpaved roads, Unpaved 

Traffic Areas.

Stabilization and opacity 

requirements for >50 

VDT or > 20 VDT (3 

axel).[D.3, E.3]

Cropland-Unpaved roads; 

Cropland- Unpaved 

vehicle/equipment traffic 

areas. [CMP List]

Mandatory 

Windblown Dust 

Controls

Yes [610.03 (A) and (B)] Yes. [D and E] No

Conservation 

Tillage incentive

Yes [610.03 (B)] Yes. [section D.1] No

Recordkeeping BMP recordkeeping form 

(name, address, signature, 

BMPs selected for each 

category, any additional 

BMPs selected for high risk 

days)) and records of changes 

to BMPs. Make available to 

APCD upon request within 2 

days. [610.03 (C) and (E)]

CMP Plan including total 

acreage, total miles 

unpaved roads, total area 

of traffic areas covered by 

CMP Plan. Description of 

CMPs implemented 

consistent with 

definitions. Supporting 

documentation necessary 

to confirm 

implementation of CMPs. 

Technical evaluation for 

alternative CMPs and 

documentation of APCD 

approval. Available to 

APCD upon request. [F 

and H] 

Upon request, make available 

to APCO a copy of each CMP 

Application and CMP Plan, 

supporting information 

necessary to confirm 

implementation of CMPs, and 

documented qualified 

exemption claim. [6.5]

Record retention 3 years [610.03 (G)] 2 years [H] 5 years [6.5]
10

Table 1: Crop 

Operations

AAC R18-2-610 and 610.03 Imperial Rule 806 SJV Rule 4550

Reporting Beginning 2017 and no more 

than once every subsequent 3 

years, submit survey form 

with specific information on 

BMPs used (e.g., acres and 

miles, BMPs selected) to 

Arizona Department of 

Agriculture (ADA) [610.03 

(D)]

None Submit to APCO for review, 

evaluation, and approval: 

CMP Application and CMP 

Plan, including map (location 

of each ag parcel, of unpaved 

roads and equipment areas 

covered by CMP Plan, where 

CMP will be implemented); 

For each parcel - CMPs 

selected, crop, AFO or other 

agricultural use of parcel. 

Information needed to 

calculate emission reductions 

(e.g., crop acreage, # animals, 

miles of roads, area of 

equipment/traffic areas 

covered by Plan.) [6.1]

Alternative 

measures

A person may develop 

different practices to control 

PM emissions not contained 

in sections 610.03 (B)(1) –

(B)(6) and may submit such 

practices that are proven 

effective through on-farm 

demonstration trials to the 

AgBMP Committee. 

Proposed new practices will 

not become effective unless 

submitted to EPA for SIP 

approval. [610.03(F)]

Owner/operator must 

submit technical 

evaluation of alternative 

CMPs to APCD, 

demonstrate emission 

reductions at least 

equivalent to other CMPs 

for that operation. APCD 

must approve alternative 

CMP before it can be 

included in Plan. [D.6]

An owner/operator may select 

a substitute CMP from another 

CMP category when no 

feasible CMP can be identified 

from one category. Not 

applicable for unpaved road 

and unpaved 

vehicle/equipment traffic area 

CMP categories. Must obtain 

interim approval of APCO 

before using. The 

owner/operator must 

demonstrate new CMP 

achieves PM10 emission 

reductions at least equivalent 

to other CMPs on list that

could be selected for the 

applicable operation. [6.2.3]

R18-2-612 and 18-2-612.01, Irrigation District rules:

Rules R18-2-612 and 18-2-612.01 are specific to unpaved roads, unpaved utility access roads, and 

canals within irrigation districts. ICAPCD Rule 805 applies to canals and canal roads. We were not able 

to find a direct comparison in the SJVUAPCD rules; however, we believe that SJV Rule 8061 would 

apply to unpaved irrigation/canal roads and areas.

Table 3 –

Irrigation 

Districts

AAC R18-2 612 and 612.01 Imperial Rule 805 SJV Rule

8061/801123

 

23 The provisions of SJV Rule 8011 General Requirements, 71 FR 8461 (February 17, 2006), are applicable to all rules under 

Regulation VIII (Fugitive PM10 Prohibitions) of the rules and regulations of the SJVUAPCD. See section 2.0. 
11

Applicability Irrigation District (ID) within a PM 

Nonattainment Area, designated after 

June 1, 2009. [612.01 (A)]

Any new or existing public of 

private paved or unpaved road, 

road construction project, or 

road modification project.

Any unpaved road 

segment with 26 or 

more annual 

average daily 

traffic. [2.0 and 

4.0]

Control 

Requirements

Implement at least one BMP per 

category.

[612.01 (A)]. BMPs defined in 612.

For canal roads with 20+ 

Average Vehicle Trips /day, 

implement at least one control 

measure in F.1 Unpaved Roads, 

including unpaved haul and 

access roads; comply with 

requirements of “Stabilized 

Unpaved Road” [Rule 800 

C.38] and limit visible dust 

emissions (VDE) to 20% 

opacity (per 800 Appendix B, 

section C), and implement other 

measures in F.2 Canal 

Roads.[E.4] 

Limit VDE to 20% 

opacity and comply 

with the 

requirements of a 

stabilized unpaved 

road by 

application/mainte

nance of at least 

one specified 

control measure, or 

implement an 

APCO-approved 

Fugitive PM10

Management Plan 

as specified in Rule 

8011. [5.2.1]. Limit 

vehicle speeds to 

25 mph. [5.2.5]

BMP 

categories

Unpaved operation and maintenance 

roads; Canals; Unpaved utility access 

roads. [612.01 (A)]

Unpaved roads (includes Haul 

and Access Roads); Canal 

Roads.

N/A

Recordkeeping BMP recordkeeping form (name, 

business address of ID representative 

responsible for BMPs, signature, date 

form signed, BMPs selected for each 

category, any changes to the BMPs. 

Make available to irrigation district 

upon request within 2 days. [612.01 

(B) and (D)]

Compile and maintain records 

that provide evidence of control 

measure application. Provide to 

APCD upon request. [G]

Control measure(s) 

used, location, 

extent of coverage, 

date, etc. 

Recordkeeping 

requirements for 

Rule 8011 apply 

[6.2]

Record 

retention

Minimum 3 years [612.01 (F)] Minimum 2 years [G] Recordkeeping 

requirements for 

Rule 8011 apply 

[6.2]

Reporting Beginning 2017 and no more than 

once every subsequent 3 years, submit 

survey form with specific information 

on BMPs used (e.g., total miles or 

canals, unpaved areas, BMPs selected) 

to ADA [612.01 (C)]

None Prepare and submit 

a written report to 

the District 

documenting

compliance with 

the rule

no less frequently 

than every 2 years. 

Include total miles 

of roads, and 

summary of action.

[6.2] 
12

Alternative

measures

An ID may develop different practices 

not contained in 612.01 (A)(1), (A)(2), 

or (A)(3) that reduce PM and may 

submit such practices proven effective 

through in-district trials. Proposed 

new practices will not become 

effective unless submitted to EPA for 

SIP approval. [612.01 (E)]

Any other method that 

effectively limits VDE to 20% 

opacity and meets the 

conditions of a Stabilized 

Unpaved Road. [F.1.g]

Any other method 

that can be 

demonstrated to 

satisfaction of 

APCD that 

effectively limits 

VDE to 20% 

opacity and meets 

the conditions of a 

stabilized unpaved 

road. [5.2.1.6]

Summary of stringency evaluation: A comparison of the AgBMP rules with the SJVUAPCD and 

Imperial CMP rules shows that the AgBMP rules are more stringent in some aspects. For example, Rule 

R18-2-610.03 has a lower applicability threshold than the other areas (at least 10 acres compared to 40 

or 100 acres for the CMP rules). Rule 18-2-610.03, unlike SJV Rule 4550, provides an incentive to 

implement conservation tillage, which has been shown to be highly effective at controlling PM10, and 

has mandatory windblown dust requirements. Rule 18-2-610.03, unlike the other rules, includes 

implementation of at least one BMP for significant earth moving activities (Section B.6). In other 

respects, the AgBMP rules are less stringent. For example, SJV Rule 4550 requires operators to submit, 

for district approval, a CMP plan with details of CMP implementation, while the AgBMP rules require 

farmers to respond to a survey every three years. The AgBMP rules do not require, as do the Imperial 

and SJV rules, a 20% opacity limit and stabilization tests for high traffic roads and areas. We note that 

EPA has approved SJV Rule 4550 and Imperial Rule 806 as satisfying BACM/BACT.

In addition to those listed in the tables above, there are other district rules that apply to agricultural 

sources. They include SCAQMD rules such as Rule 403 Fugitive Dust. SCAQMD Rule 403 exempts 

crop operations as long as they follow the control measures in the Agricultural Handbook for the area.24

These handbooks contain similar types of controls as the AgBMP rules, but are more stringent in some 

aspects and less in other aspects. SJV Rule 8081, applies to off-field agricultural sources, and includes 

stabilization and 20% opacity requirements, which appears to be more stringent than the AgBMP rules. 

We note that EPA has approved SCAQMD Rules 403, and SJV Rule 8081 as satisfying BACM/BACT.

3. SIP Relaxation evaluation: The submitted AgBMP rules and rule revisions are more stringent 

than the State’s previously adopted SIP-approved versions of these rules (October 11, 2001, 66 FR 

51872) because the new rules and revisions have set standards for compliance with commercial farming 

BMPs (e.g., reducing at least one tilling operation or ground operation, establishing a minimum 

percentage or depth of ground cover), there are added regulations irrigation districts, and the rules apply 

to a larger geographic area. We propose to determine that our approval of the submitted rules and rule 

revisions that are the subject of this TSD would comply with CAA §§110(l) and 193 because (1) the 

proposed SIP revision would not interfere with the on-going process for ensuring that requirements for 

RFP and attainment of the NAAQS are met, and (2) the emission standards in the submitted rules are 

more stringent than the existing SIP-approved control requirements that they would replace.

 

24 “Rule 403 Coachella Valley Agricultural Handbook, Measures to Reduce Dust from Agricultural Operations in the 

Coachella Valley, SCAQMD, April 2004; Rule 403 Agricultural Handbook, Measures to Reduce Dust from Agricultural 

Operations in the South Coast Air Basin, SCAQMD, December 1988.
13

ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION - The following 

revisions are not currently the basis for rule disapproval, but are recommended for the next time the rule 

is amended. 

1. We recommend adding stabilization and 20% opacity requirements for high traffic unpaved 

roads/feed lanes and equipment/traffic areas, and adopting appropriate stabilization and opacity 

test methods.

2. R18-2-610.03(C) and R18-2-612.01(B): These sections state that the BMP Forms must be 

provided to the Director within two business days of notice. We recommend that the rule include 

a provision that states that the BMP Forms must be provided to an inspector upon request. 

3. R18-2-610(19): The Crop BMP definitions specify an associated reduction in activity (e.g., 

reduce one tillage operation), but this language is lacking in the Equipment Modification BMP. 

Please consider specifying in the Equipment Modification BMP definition the minimum amount 

of tillage or ground/harvest operations reduced. In addition, we recommend that the farmer be 

required to describe on the BMP Form and Survey the type of equipment and how it was 

modified to reduce PM10 emissions. 

4. R18-2-610(54); and R18-2-612(27): We recommend that the rules define the term “stabilized 

soil surface.”

5. R18-2-610.03; R18-2-612.01; We recommend that the rules require that records be maintained 

for five years instead of three.

6. R18-2-610, R18-2-612: We recommend that the rules define the term “Director” and 

“Department.”

7. R18-2-610(45): Please correct the cross-reference to ARS 49-457.

8. The title of R18-2-610.03 is inconsistent on pages GVI-8 and GVI-16. Page GVI-8 uses the title, 

“Agricultural PM General Permit for Commercial Farms; Pinal County PM Nonattainment 

Area;” the title on page GVI-16 is “Agricultural PM General Permit for Crop Operations: Pinal 

County PM Nonattainment Area.” Please revise for consistency.

9. The title of R18-2-612.01 is inconsistent on pages GVI-8 and GVI-37. Please revise for 

consistency. 

EPA ACTION

The following submitted rules are enforceable, strengthen the SIP by adding new control measures or 

revising and improving existing requirements, and fulfil the relevant CAA section 110 requirements for 

nonattainment areas: 

AAC R18-2-610 Definitions for R18-2-610.01, R18-2-610.02, and R18-2-610.03; 

AAC R18-2-610.3 Agricultural PM General Permit for Crop Operations: Pinal County PM 

Nonattainment Area; 

ACC R18-2-612 Definitions for R18-2-612.01; 

ACC 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. Therefore, EPA staff recommends approval of these rules 

pursuant to CAA §110(k)(3) and §301(a). 

REFERENCES
14

1. “Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,” (a.k.a., Bluebook) 

EPA OAQPS, May 25, 1988.

2. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,” (a.k.a., Little 

Bluebook), EPA Region 9, August 21, 2001.

3. “Rule 4550 – Conservation Management Practices,” SJVUAPCD, August 19, 2004. Approved 

71 FR 7683, February 14, 2006.

4. “Rule 8081 – Agricultural Sources, September 16, 2004. Approved 71 FR 8461, February 17, 

2006.

5. “Rule 8061 – Paved and Unpaved Roads,” SJVUAPCD, August 19, 2004. Approved 71 FR 

8461, February 17, 2006.

6. “Rule 8011 – General Requirements,” SJVUAPCD, August 19, 2004. Approved 71 FR 8461, 

February 17, 2006.

7. “Rule 806 – Conservation Management Practices,” ICAPCD, October 16, 2012. Approved 78 

FR 23677, April 22, 2013.

8. “Rule 805 – Paved and Unpaved Roads,” SJVUAPCD, October 16, 2012. Approved 78 FR 

23677, April 22, 2013.

9. “Rule 800 – General Requirements for Control of Fine Particulate Matter,” ICAPCD, October 

16, 2012. Approved 78 FR 23677, April 22, 2013.

10. “Rule 420 – Beef Feedlots,” ICAPCD, August 13, 2002. Approved 68 FR 8839, February 23, 

2003.

11. “Rule 403 – Fugitive Dust,” SCAQMD, June 3, 2005. Approved 73 FR 12639, March 10, 2008.

12. “Rule 403 Coachella Valley Agricultural Handbook, Measures to Reduce Dust from Agricultural 

Operations in the Coachella Valley, SCAQMD, April 2004

13. Rule 403 Agricultural Handbook, Measures to Reduce Dust from Agricultural Operations in the 

South Coast Air Basin, SCAQMD, December 1988.

14. April 8, 2016 email correspondence between H. Haggerty, ADEQ and N. Levin, EPA re: 

Appendix 2.

.