```

[Federal Register Volume 66, Number 126 (Friday, June 29, 2001)]
[Proposed Rules]
[Pages 34598-34602]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-16439]

-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[AZ105-0040; FRL-7005-4]

Approval and Promulgation of Implementation Plans; Arizona-- 
Maricopa Nonattainment Area; PM-10

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

-----------------------------------------------------------------------

SUMMARY: EPA is proposing to approve under the Clean Air Act (CAA or 
Act), as a revision to the Arizona State Implementation Plan (SIP), a 
general permit rule that provides for the expeditious implementation of 
best management practices (BMPs) to reduce particulate matter (PM-10) 
from agricultural sources in the Maricopa County (Phoenix) PM-10 
nonattainment area. EPA is proposing to approve the general permit rule 
as meeting the ``reasonably available control measure'' (RACM) 
requirements of the Act.

DATES: Written comments will be accepted until July 30, 2001.

ADDRESSES: Comments should be submitted (in duplicate, if possible) to: 
John Ungvarsky, EPA Region 9, 75 Hawthorne Street (AIR2), San 
Francisco, CA 94105 or [email protected].
    A copy of docket, containing material relevant to EPA's proposed 
action, is available for review at: EPA Region 9, Air Division, 75 
Hawthorne Street, San Francisco, CA 94105. Interested persons may make 
an appointment with John Ungvarsky to inspect the docket at EPA's San 
Francisco office on weekdays between 9 a.m. and 4 p.m.
    A copy of docket is also available to review at the Arizona 
Department of Environmental Quality, Library, 3033 N. Central Avenue, 
Phoenix, Arizona 85012. (602) 207-2217.
    Electronic Availability.This document is also available as an 
electronic file on EPA's Region 9 Web Page at http://www.epa.gov/region09/air.

FOR FURTHER INFORMATION CONTACT: John Ungvarsky at (415) 744-1286 or 
[email protected].

SUPPLEMENTARY INFORMATION

I. Background

A. Air Quality Status

    Portions of Maricopa County \1\ are designated nonattainment for 
the PM-10 national ambient air quality standards (NAAQS) \2\ and were 
originally classified as ``moderate'' pursuant to section 188(a) of the 
CAA. 56 FR 11101 (March 15, 1991). On May 10, 1996, EPA reclassified 
the Maricopa County PM-10 nonattainment area to ``serious'' under CAA 
section 188(b)(2). 61 FR 21372. Having been reclassified, Phoenix is 
required to meet the serious area requirements in CAA section 189(b).
---------------------------------------------------------------------------

    \1\ ``Maricopa,'' ``Maricopa County'' and ``Phoenix'' are used 
interchangeably throughout this proposal to refer to the 
nonattainment area.
    \2\ There are two PM-10 NAAQS, a 24-hour standard and an annual 
standard. 40 CFR 50.6. EPA promulgated these NAAQS on July 1, 1987 
(52 FR 24672), replacing standards for total suspended particulate 
with new standards applying only to particulate matter up to 10 
microns in diameter (PM-10). At that time, EPA established two PM-10 
standards. The annual PM-10 standard is attained when the expected 
annual arithmetic average of the 24-hour samples for a period of one 
year does not exceed 50 micrograms per cubic meter (g/
m3). The 24-hour PM-10 standard of 150 g/
m3 is attained if samples taken for 24-hour periods have 
no more than one expected exceedance per year, averaged over 3 
years. See 40 CFR 50.6 and 40 CFR part 50, appendix K.
---------------------------------------------------------------------------

    While the Phoenix PM-10 nonattainment area is currently classified 
as serious, today's proposed action relates only to the moderate area 
statutory requirements for RACM. However, as discussed further below, 
Arizona developed state legislation and a general permit rule 
applicable to agricultural sources of PM-10 when the area had already 
been reclassified to serious. Therefore the State's focus was on the 
serious area statutory requirements for ``best available control 
measures'' (BACM). RACM, as will be seen, is generally considered to be 
a subset of BACM. As a result, in order to evaluate whether the general 
permit rule meets the RACM requirements for the purpose of this 
rulemaking, it was necessary for EPA to refer to portions of the 
State's serious area state implementation plan (SIP) submittals. Thus, 
while the Agency is not proposing action at this time on those 
submittals as they relate to the Act's serious area statutory 
requirements, those requirements and the State's submittals developed 
to meet them are discussed here. The relevant portions of the State's 
serious area submittals are cited below and are included in the docket 
for this proposed action.

B. CAA Planning Requirements and EPA Guidance

    The air quality planning requirements for PM-10 nonattainment areas 
are set out in subparts 1 and 4 of title I of the Clean Air Act. Those 
states containing initial moderate PM-10 nonattainment areas were 
required to submit, among other things, by November 15, 1991 provisions 
to assure that RACM (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)) shall 
be implemented no later than December 10, 1993. CAA sections 172(c)(1) 
and 189(a)(1)(C). Since that deadline has passed, EPA has concluded 
that the required RACM/RACT must be implemented ``as soon as 
possible.'' Delaney v. EPA, 898 F.2d 687, 691 (9th Cir. 1990). EPA has 
interpreted this requirement to be ``as soon as practicable.'' See 55 
FR 41204, 41210 (October 1, 1990) and 63 FR 28898, 28900 (May 27, 
1998).
    EPA has issued a ``General Preamble'' \3\ describing EPA's 
preliminary views on how the Agency intends to review SIPs and SIP 
revisions submitted under title I of the Act, including those state 
submittals containing moderate PM-10 nonattainment area SIP provisions. 
The methodology for determining RACM/RACT is described in detail in the 
General Preamble. 57 FR 13498, 13540-13541. In short and as pertinent 
here, EPA suggests starting to define RACM with the list of available 
control measures for fugitive dust in Appendix C1 to the General 
Preamble and adding to this list any additional control measures 
proposed and documented in public comments. Any measures that apply to 
emission sources of PM-10 and that are de minimis and any measures that 
are unreasonable for technology reasons or because of the cost of the 
control in the area can then be culled from the list. In addition, 
potential RACM may be culled from the list if a measure cannot be 
implemented on a schedule that would advance the date

[[Page 34599]]

for attainment in the area. 57 13498, 13560; 57 FR 18070, 18072 (April 
28, 1992).
---------------------------------------------------------------------------

    \3\ See ``State Implementation Plans; General Preamble for the 
Implementation of Title I of the Clean Air Act Amendments of 1990,'' 
(General Preamble) 57 FR 13498 (April 16, 1992) and 57 FR 18070 
(April 28, 1992).
---------------------------------------------------------------------------

    PM-10 nonattainment areas reclassified as serious under section 
188(b)(2) of the CAA are required to submit, within 18 months of the 
area's reclassification, SIP revisions providing for the implementation 
of BACM no later than four years from the date of reclassification. The 
SIP must also provide for attainment of the PM-10 NAAQS by December 31, 
2001. See CAA sections 188(c)(2) and 189(b). If certain conditions are 
met, EPA may extend this attainment deadline to no later than December 
31, 2006. One of these conditions is that the serious area plan must 
include the ``most stringent measures'' (MSM) included in the plan of 
any state or achieved in practice in any state that can feasibly be 
implemented in the area. CAA section 188(e).
    On August 16, 1994, EPA issued an Addendum to the General Preamble 
that describes the Agency's preliminary views on the CAA provisions for 
serious area PM-10 nonattainment SIPs. 59 FR 41998. The Addendum 
provides that for moderate PM-10 areas reclassified as serious, the 
RACM requirements are carried over and elevated to a higher level of 
stringency, i.e., BACM. 59 FR 41998, 42009.
    Moderate and serious area plans are also required to meet the 
generally applicable SIP requirements for reasonable notice and public 
hearing under section 110(a)(2), necessary assurances that the 
implementing agencies have adequate personnel, funding and authority 
under section 110(a)(2)(E)(i) and 40 CFR 51.280; and the description of 
enforcement methods as required by 40 CFR 51.111, and EPA guidance 
implementing these provisions.

C. Recent History of PM-10 Planning in the Phoenix Area

    On August 3, 1998, EPA promulgated under the authority of CAA 
section 110(c)(1) a federal implementation plan (FIP) to address the 
CAA's moderate area PM-10 requirements for the Phoenix PM-10 
nonattainment area. 63 FR 41326 (August 3, 1998). EPA's PM-10 FIP for 
the Phoenix area was the result of over six years of planning and 
litigation regarding the control of PM-10 emissions in the Phoenix 
area. For a detailed discussion of that history, the reader is referred 
to EPA's proposed rulemaking for the FIP at 63 FR 15920, 15924-15926 
(April 1, 1998).
    In the FIP, EPA promulgated, among other things, a demonstration 
that RACM will be implemented in the Phoenix area as soon as 
practicable. As part of its RACM demonstration, EPA promulgated an 
enforceable commitment, codified at 40 CFR 52.127, to ensure that RACM 
for agricultural sources would be expeditiously adopted and 
implemented. See 63 FR 41326, 41350.
    In May 1998, Arizona Governor Hull signed into law Senate Bill 1427 
(SB 1427) which revised title 49 of the Arizona Revised Statutes (ARS) 
by adding section 49-457. This legislation established an Agricultural 
Best Management Practices (BMP) Committee \4\ that was required to 
adopt by rule by June 10, 2000, an agricultural general permit 
specifying BMPs for regulated agricultural activities \5\ to reduce PM-
10 emissions in the Maricopa PM-10 nonattainment area. ARS 49-457.A-F. 
Subsection M of ARS 49-457 provided for the initiation of BMP 
implementation through the commencement of an education program by June 
10, 2000.
---------------------------------------------------------------------------

    \4\ The Committee is composed of five local farmers, the 
Director of the Arizona Department of Environmental Quality (ADEQ), 
the Director of the Arizona Department of Agriculture, the State 
Conservationist for the United States Department of Agriculture's 
(USDA) Natural Resources Conservation Service (NRCS) state office, 
the Dean of the University of Arizona's College of Agriculture, and 
a soil scientist from the University of Arizona.
    \5\ Subsection N.1 of ARS 49-457 defines ``agricultural general 
permit'' to mean: ``best management practices that: (a) reduce PM-10 
particulate emissions from tillage practices and from harvesting on 
a commercial farm.[;] (b) reduce PM-10 particulate emissions from 
those areas of a commercial farm that are not normally in crop 
production. [;] (c) reduce PM-10 particulate emissions from those 
areas of a commercial farm that are normally in crop production 
including prior to plant emergence and when the land is not in crop 
production.''
    ``Regulated agricultural activities'' are defined as 
``commercial farming practices that may produce PM-10 particulate 
emissions within the Maricopa PM-10 particulate nonattainment 
area.'' ARS 49-457.N.4.
---------------------------------------------------------------------------

    On September 4, 1998, the State submitted ARS 49-457 to EPA for 
inclusion in the Arizona SIP as meeting the RACM requirements of CAA 
section 189(a)(1)(C) and requested that the Agency approve that 
legislation in place of the FIP commitment in 40 CFR 52.127. On June 
29, 1999, EPA approved ARS 49-457 as meeting the RACM requirements of 
the CAA and withdrew the FIP commitment. 64 FR 34726.
    Pursuant to section 189(b)(2), on February 16, 2000, the State 
submitted as a revision to the PM-10 SIP the ``Revised Maricopa 
Association of Governments (MAG) 1999 Serious Area Particulate Plan for 
PM-10 for the Maricopa County Nonattainment Area'' (1999 serious area 
plan). Among other things, this plan provides for attainment of both 
the annual and 24-hour PM-10 NAAQS by December 31, 2006 and relies on 
ARS 49-457 for the purpose of addressing the CAA's BACM and MSM 
requirements for agricultural sources.
    On April 13, 2000, EPA proposed to approve the 1999 serious area 
plan as it relates to the annual PM-10 standard and to grant the 
State's request to extend the attainment date for the annual standard 
to December 31, 2006. 65 FR 19964. EPA took no action on the serious 
area plan's provisions for the 24-hour standard because the attainment 
demonstration relies on BMPs that had not yet been quantified by the 
State. 65 FR at 19970.

II. Arizona's Agricultural General Permit

    As directed by ARS 49-457, the Agricultural BMP Committee adopted 
the agricultural general permit and associated definitions, effective 
May 12, 2000, at Arizona Administrative Code (AAC) R18-2-610, 
``Definitions for R18-2-611,'' and 611, ``Agricultural PM-10 General 
Permit; Maricopa PM10 Nonattainment Area'' (collectively, general 
permit rule). On July 11, 2000, the State submitted AAC R18-2-610 and 
611 to EPA as a revision to the Arizona SIP.\6\
---------------------------------------------------------------------------

    \6\ This submittal was deemed complete by operation of law on 
January 11, 2001 pursuant to CAA section 110(k)(1)(B).
---------------------------------------------------------------------------

    In addition to fulfilling the commitment in ARS 49-457 approved by 
EPA as part of the moderate area PM-10 plan, this submittal was 
intended to partially satisfy the CAA's serious area PM-10 
requirements; the State indicated that documentation for the remaining 
portions of the serious area SIP revision package would be submitted at 
a later date.\7\ On April 26, 2001, the State submitted this additional 
documentation as part of a draft revision to the 1999 serious area plan 
and requested parallel processing, a procedure adopted by EPA to 
expedite review of a state plan. See 40 CFR part 51, appendix V, 
section 2.3.1. The State formally submitted the final revision to EPA 
on June 13, 2001. This submittal includes an attainment demonstration 
for the 24-hour standard, BACM and MSM demonstrations, description of 
the public education initiative for the general permit, and a 
demonstration that the CAA section 110 general requirements have been 
met.\8\
---------------------------------------------------------------------------

    \7\ ``Maricopa County, PM10 State Implementation Plan 
Revision: Agricultural Best Management Practices,'' Richard W. Tobin 
II, ADEQ, to Felicia Marcus, EPA, July 11, 2000.
    \8\ ``Submittal of State Implementation Plan revision for the 
Agricultural Best Management program in the Maricopa County, 
PM10 Nonattainment Area'' from Jacqueline E. Schafer, 
ADEQ, to Laura Yoshii, EPA, June 13, 2001.

---------------------------------------------------------------------------

[[Page 34600]]

    In this action, EPA is proposing only to approve the general permit 
rule as meeting the CAA's RACM requirements. For this purpose, the 
Agency reviewed the portions of the June 13, 2001 submittal relating to 
the BACM and MSM demonstrations, public education initiative and CAA 
section 110 requirements. EPA will formally evaluate the general permit 
rule in relation to the BACM and MSM requirements in the context of a 
future rulemaking on the 1999 serious area plan.
    AAC R18-2-611 includes thirty-four BMPs identified by the BMP 
Committee as feasible, effective, and common sense practices that will 
reduce PM-10 emissions while minimizing negative economic impacts on 
local agriculture.
    A BMP is defined in AAC R18-2-610 as ``a technique verified by 
scientific research, that on a case-by-case basis is practical, 
economically feasible and effective in reducing PM-10 particulate 
emissions from a regulated agricultural activity.''
    AAC R18-2-611 requires a commercial farmer \9\ to implement by 
December 31, 2001 at least one BMP to control PM-10 for three 
categories of emission sources: tillage and harvest, non-cropland, and 
cropland.\10\
---------------------------------------------------------------------------

    \9\ R18-2-610 defines commercial farmer ``an individual, entity, 
or joint operation in general control of 10 or more continuous acres 
of land used for agricultural purposes within the boundary of the 
Maricopa County PM10 nonattainment area.''
    \10\ R18-2-610 defines tillage and harvest as ``any mechanical 
practice that physically disturbs cropland or crops on a commercial 
farm.'' R18-2-610 defines non-cropland as ``any commercial farm land 
that: is no longer used for agricultural production; is no longer 
suitable for production of crops; is subject to a restrictive 
easement of contract that prohibits use for the production of crops; 
or includes a private farm road, ditch, ditch bank, equipment yard, 
storage yard, or well head.'' R18-2-610 defines cropland as ``land 
on a commercial farm that: is within the time frame of final harvest 
to plant emergence; has been tilled in a prior year and is suitable 
for crop production, but is currently fallow; is a turn-row.''
---------------------------------------------------------------------------

    To reduce PM-10 emissions during tillage and harvest activities, a 
commercial farmer shall implement at least one of following BMPs: 
Chemical irrigation; combining tractor operations; equipment 
modification; limited activity during high-wind event; multi-year crop; 
planting based on soil moisture; reduced harvest activity; reduced 
tillage system; tillage based on soil moisture; or timing of tillage 
operation.
    To reduce PM-10 emissions from non-cropland, a commercial farmer 
shall implement at least one of following BMPs: access restriction; 
aggregate cover; artificial wind barrier; critical area planting; 
manure application; reduced vehicle speed; synthetic particulate 
suppressant; track-out control system; tree, shrub, or windbreak 
planting; or watering.
    To reduce PM-10 emissions from cropland, a commercial farmer shall 
implement at least one of following BMPs: artificial wind barrier; 
cover crop; cross-wind ridges; cross-wind strip-cropping; cross-wind 
vegetative strips; manure application; mulching; multi-year crop; 
permanent cover; planting based on soil moisture; residue management; 
sequential cropping; surface roughening; or tree, shrub, or windbreak 
planting.
    A commercial farmer is required to maintain a record demonstrating 
compliance with the general permit. A commercial farmer not in 
compliance with the general permit is subject to a series of compliance 
actions described in ARS 49-457.I-K.
    The BMP Committee began implementing the general permit rule in 
June 2000 by means of an extensive educational outreach program 
informing growers about the BMPs. In addition, the BMP Committee 
developed a Guide to Agricultural PM-10 Best Management Practices \11\ 
to provide information and guidance on how to effectively implement 
BMPs. The guide represents a significant step in helping growers reduce 
PM-10 emissions from farmlands located within the Maricopa County PM-10 
nonattainment area.
---------------------------------------------------------------------------

    \11\ ``Guide to Agricultural PM-10 Best Management Practices, 
Maricopa County, Arizona PM-10 Nonattainment Area,'' Governor's 
Agricultural BMP Committee, First edition, February, 2001.
---------------------------------------------------------------------------

    The BMP Committee developed an Agricultural BMP General Permit 
Education Program to inform and educate the public and growers about 
the forthcoming general permit. As of July 2000 nine public 
presentations had been given in addition to the twenty-two public 
meetings held by the BMP Committee.\12\ Informational public workshops 
for growers were held on February 20, 2001 and March 1, 2001.\13\ The 
workshops focused on the purpose of the rule, the individual BMPs, 
recordkeeping requirements, and compliance options. In addition, ADEQ 
plans to hold an annual workshop to educate growers, inspectors, and 
interested stakeholders.
---------------------------------------------------------------------------

    \12\ See Enclosure 3, ``Final Revised Background Information,'' 
BACM--Recommendations from Governor's Agricultural BMP Committee, 
pages 31-33 of June 13, 2001, Submittal of State Implementation Plan 
revision for the Agricultural Best Management Practices program in 
the Maricopa Count PM-10 Nonattainment Area.
    \13\ Ibid.
---------------------------------------------------------------------------

    In addition to the guide referenced above, the BMP Committee 
developed a brochure to inform the public and growers about PM-10 and 
the BMPs.\14\
---------------------------------------------------------------------------

    \14\ ``How Agriculture is Improving Maricopa County's Air 
Quality,'' Governor's Agricultural BMP Committee, March, 2001.
---------------------------------------------------------------------------

III. SIP Approval Criteria

    Once a SIP submittal is deemed complete, EPA must next determine if 
the submittal is approvable as a revision to the SIP. EPA must first 
determine whether the general permit rule meets the RACM requirements 
of CAA section 189(a)(1)(C) and EPA guidance interpreting that 
provision. EPA must also determine that the rule meets the general SIP 
requirements described in section I.B. above.
    Finally, in order for EPA to approve the SIP revision, EPA must 
determine that the SIP submittal complies with CAA section 110(l). 
Section 110(l) states that the ``Administrator shall not approve a 
revision of a plan if the revision would interfere with any applicable 
requirement concerning attainment and reasonable further progress * * * 
or any other applicable requirement of [the Clean Air] Act.''

IV. Evaluation of the Agricultural General Permit Rule

A. RACM Requirements

    CAA section 189(a)(1)(C), as interpreted by EPA under the current 
circumstances, requires that a moderate area plan provide for the 
implementation of RACM as soon as practicable. Arizona's requirements 
regarding the timing of the implementation of the BMPs are contained in 
ARS 49-457. Since EPA has already approved this legislation as meeting 
the ``as expeditiously as practicable'' test and the general permit 
rule was adopted in compliance with the statute, EPA need not revisit 
the timing issue in this rulemaking. See 64 FR 34726.\15\
---------------------------------------------------------------------------

    \15\ ACC R18-2-611 reiterates the compliance deadlines contained 
in ARS 49-457.
---------------------------------------------------------------------------

    Therefore EPA need only determine whether the BMPs in the general 
permit rule meet the level of control required by CAA section 
189(a)(1)(C). As discussed above, for this evaluation, EPA looked to 
the State's BACM and MSM analyses in the June 13, 2001 submittal.\16\
---------------------------------------------------------------------------

    \16\ See reference in footnote 8.
---------------------------------------------------------------------------

     In September 1998, the Agricultural BMP Committee was established 
for the purpose of developing an agricultural general permit specifying 
BMPs.\17\ The

[[Page 34601]]

established an Ad-hoc Technical Group to develop a comprehensive list 
of potential BMPs for regulated sources in the Maricopa nonattainment 
area. Participants included the USDA NRCS, USDA Agricultural Research 
Service, University of Arizona College of Agriculture, ADEQ, University 
of Arizona College of Agriculture and Cooperative Extension, Western 
Growers Association, Arizona Cotton Growers Association, Arizona Farm 
Bureau Federation, and EPA.
---------------------------------------------------------------------------

    \17\ See reference in footnote 12, pages 9-26.
---------------------------------------------------------------------------

    The Ad-hoc Technical Group reviewed available dust control 
regulations, literature, and technical documents, and developed a list 
of conservation practices potentially suitable to agricultural sources 
in the Maricopa County nonattainment area. The information sources 
evaluated are listed in Table 1.

  Table 1.--Information Sources Used To Develop a List of Conservation
        Practices With Potential Applicability in Maricopa County
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
NRCS Field Office Technical Guide.
South Coast Air Quality Management District Rule 403 (fugitive dust)
 Agricultural Handbook.
San Joaquin Valley Unified Air Pollution Control District 1997 PM-10
 Attainment Demonstration Plan.
University of Arizona Cooperative Extension Mojave Valley research
 project.
University of Washington Columbia Plateau research project.
ENSR Report: Evaluation of Fugitive Dust Control in the Maricopa County
 PM-10 Nonattainment Area. March 1997. Document Number 0493-015-500.
Particulate Control Measure Feasibility Study: Volumes I and II.
 Prepared for the Maricopa Association of Governments by Sierra
 Research. January 1997.
------------------------------------------------------------------------

    From a review of these information sources, 65 potential practices 
for further consideration were selected.\18\ These 65 measures 
represented a broad spectrum of potential BMPs, many of which related 
to conservation practices used in the western United States that had 
never been evaluated in the context of reducing PM-10. This list 
represented a list of potential practices to be considered in 
determining what measures are actually available for implementation in 
the Phoenix area.
---------------------------------------------------------------------------

    \18\ See reference in footnote 12, pages 15-16.
---------------------------------------------------------------------------

    The Agricultural BMP Committee thoroughly reviewed the potential 
practices presented by the Ad-hoc Technical Group and identified 34 
\19\ of the 65 BMPs to include in the general permit rule that the 
Committee deemed to be feasible, effective and common sense practices 
for the Phoenix area which also minimized potential negative impacts on 
local agriculture.
---------------------------------------------------------------------------

    \19\ The BMP Committee divided the 34 BMPs by applicability to 
the three source categories: 10 BMPs were applicable to the Tillage 
and Harvest category; 10 BMPs were applicable to the Non-Cropland 
category; and 14 BMPs were applicable to the Cropland category.
---------------------------------------------------------------------------

    Of the 31 potential BMPs eliminated, the majority were dropped 
because they either duplicated another BMP or did not reduce PM-10. 
Other reasons for elimination included the impracticability of a BMP 
for the Maricopa County Area, lack of cost effectiveness, or 
infeasibility of implementation.\20\ Examples of how potential BMPs 
were eliminated for these reasons are provided below:
---------------------------------------------------------------------------

    \20\ See reference in footnote 12, pages 17-18.
---------------------------------------------------------------------------

    (1) No identifiable relation to PM-10 emission reductions. For 
example, the original list of potential BMPs developed by the Ad-hoc 
Technical Committee included a potential BMP for Tree/Shrub Pruning. 
Although the Tree/Shrub Pruning might qualify as a BMP for some 
agricultural activities, it would not reduce PM-10. Therefore, the 
Tree/Shrub Pruning was dropped.
    (2) Duplication. Many similar BMPs were combined into a single BMP. 
For example, the original list of potential BMPs included numerous 
practices that relate to creating a barrier (i.e., Tree/shrub 
establishment, windbreak/shelterbelt establishment, windbreak/
shelterbelt renovation, hedgerow plating, herbaceous wind barriers) to 
reduce the impact of wind on disturbed soils. These practices were 
combined into a single BMP: tree, shrub, or windbreak planting.
    (3) Impracticability to Maricopa County farming or implementation 
infeasibility. Some of the potential BMPs were determined to be 
impractical or infeasible. For example, the original list included 
Wildlife Upland Habitat Management. This conservation practice is 
intended to create, maintain, or enhance habitat suitable to sustaining 
desired kinds of upland wildlife.\21\ Although evaluated as a potential 
BMP, it was determined to be impracticable for Maricopa County given 
that the agricultural sources in question are not located in an area 
suitable for upland wildlife.
---------------------------------------------------------------------------

    \21\ USDA Natural Resources Conservation Service, Arizona; 
Conservation Practice Summary; Air Quality (cropland--irrigated), 
FOTG Section IV, November, 1998.
---------------------------------------------------------------------------

    The general permit rule, as finally adopted by the BMP Committee in 
May 2000, requires that commercial farmers implement at least one BMP 
for the Tillage and Harvest, Cropland, and Non-cropland categories by 
December 31, 2001. Because of the variety, complexity, and uniqueness 
of farming operations, the BMP Committee concluded that farmers need a 
variety of BMPs to choose from in order to tailor PM-10 controls to 
their individual circumstances. Further, the BMP Committee acknowledged 
that there is a limited amount of scientific information available 
concerning the emission reduction and cost effectiveness of some BMPs, 
especially in relation to Maricopa County. The BMP Committee balanced 
these limitations with the common sense recognition that the BMPs would 
reduce wind erosion and the entrainment of agricultural soils, thereby 
reducing PM-10. Given the limited scientific information available and 
the myriad factors that affect farming operations, the BMP Committee 
concluded that requiring more than one BMP could not be considered 
technically justified and could cause an unnecessary economic burden to 
farmers. Instead, the BMP Committee and ADEQ committed to monitor the 
effectiveness of the BMPs and adjust the program, if needed, in the 
future.
    There are only two PM-10 nonattainment areas in the nation that are 
currently requiring agricultural sources to reduce PM-10 emissions. The 
South Coast Air Quality Management District (SCAQMD), which includes 
the agricultural areas of western Riverside County and the Coachella 
Valley, is implementing Rules 403 and 403.1 to reduce PM-10 emissions 
from agricultural sources. The Arizona general permit rule represents 
the only other measure in the country that requires the implementation 
of BMPs to reduce PM-10. Because agricultural sources vary by factors 
such as regional climate, soil type, growing season, crop type, water 
availability, and relation to urban centers, agricultural PM-10 
strategies must be based on local factors. Therefore, while the 
Committee surveyed measures adopted in other geographic areas, they are 
of limited utility in determining what measures are available for 
Maricopa County area. In order to justify additional requirements for 
farming operations in the area beyond those in the general permit rule, 
a significant influx of money and additional research would be needed.
    The development of the general permit rule was a multi-year 
endeavor involving an array of experts in agricultural practices. As 
noted, Arizona is one of the few areas where regulation of PM-10 
emissions from the agricultural sector has even been attempted. Based 
on the available

[[Page 34602]]

information, EPA believes that the general permit rule represents a 
comprehensive, sensible approach that meets, and in fact far exceeds, 
the RACM requirements of CAA section 189(a)(1)(C) and EPA guidance 
interpreting those requirements.

B. General SIP Requirements

    EPA has concluded that the State's June 13, 2001 submittal provides 
the necessary assurances of adequate personnel and funding required by 
CAA section 110(a)(2)(E)(i) and 40 CFR 51.280 to carry out the general 
permit program.\22\ ADEQ intends to fund the program through resources 
currently allocated to the State's existing general permit and 
compliance program. Based on historical data, ADEQ anticipates a 
decreasing agricultural source population and, therefore, does not see 
the need for increased funding to administer the program.
---------------------------------------------------------------------------

    \22\ See reference in footnote 8, pages 33-35.
---------------------------------------------------------------------------

    For the general permit program, ADEQ intends to inspect commercial 
farms every two to three years. In addition, ADEQ intends to develop in 
2002 a compliance initiative that selects a geographic area within the 
nonattainment area for inspections. Based on the results, other 
initiatives may be developed. Moreover, ADEQ's Air Compliance Section 
will respond to agricultural related complaints within five working 
days. ADEQ will also develop a process whereby air inspectors from 
other agencies will notify ADEQ if they observe an alleged violation or 
receive a complaint, and an ADEQ inspector will conduct a timely 
investigation.
    EPA has also concluded that the general permit rule, as informed by 
ARS 49-457 and the State's June 13, 2001 submittal, meets the 
requirements of 40 CFR 51.111. This provision requires a description of 
enforcement methods, including procedures for monitoring compliance 
(discussed above), procedures for handling violations, and designation 
of agency responsibility for enforcement of implementation. ARS 49-
457.I, J, and K and AAC R18-2-611.K and L give ADEQ specific authority 
to address noncompliance with the general permit rule and includes the 
steps the department will take to enforce the rule. ADEQ's Air 
Compliance Section routinely updates its database to include general 
information regarding complaints and enforcement actions which can be 
utilized in future years to determine rule effectiveness.

C. CAA Section 110(l)

    In its rulemaking on ARS 49-457, EPA concluded that approval of the 
State legislation and withdrawal of the FIP commitment would not 
interfere with the attainment, reasonable further progress and RACM 
requirements of the CAA. 63 FR 71815, 71817. Since the general permit 
rule strengthens the SIP by providing specific BMPs in place of the 
commitment to adopt BMPs in ARS 49-457, EPA's proposed approval meets 
the requirements of CAA section 110(l).

V. Proposed Actions

    EPA has evaluated ACC R18-2-610 and 611 and has determined that 
these rules are consistent with the CAA and EPA policy. Therefore, EPA 
is proposing to approve ACC R18-2-610 and 611 under section 110(k)(3) 
of the CAA as meeting the requirements of sections 110(a) and 
189(a)(1)(C).
    Nothing in this action should be construed as permitting or 
allowing or establishing a precedent for any future request for 
revision to any SIP. Each request for revision to the SIP shall be 
considered separately in light of specific technical, economic, and 
environmental factors and in relation to relevant statutory and 
regulatory requirements.

VI. Administrative Requirements

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this 
proposed action is not a ``significant regulatory action'' and 
therefore is not subject to review by the Office of Management and 
Budget. This proposed action merely approves state law as meeting 
federal requirements and imposes no additional requirements beyond 
those imposed by state law. Accordingly, the Administrator certifies 
that this proposed rule will not have a significant economic impact on 
a substantial number of small entities under the Regulatory Flexibility 
Act (5 U.S.C. 601 et seq.). Because this rule proposes to approve pre-
existing requirements under state law and does not impose any 
additional enforceable duty beyond that required by state law, it does 
not contain any unfunded mandate or significantly or uniquely affect 
small governments, as described in the Unfunded Mandates Reform Act of 
1995 (Pub. L. 104-4). This rule also does not have a substantial direct 
effect on one or more Indian tribes, on the relationship between the 
Federal Government and Indian tribes, or on the distribution of power 
and responsibilities between the Federal Government and Indian tribes, 
as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), 
nor will it have substantial direct effects on the States, on the 
relationship between the national government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government, as specified in Executive Order 13132 (64 FR 43255, August 
10, 1999), because it merely approves a state rule implementing a 
federal standard, and does not alter the relationship or the 
distribution of power and responsibilities established in the Clean Air 
Act. This proposed rule also is not subject to Executive Order 13045 
(62 FR 19885, April 23, 1997), because it is not economically 
significant.
    In reviewing SIP submissions, EPA's role is to approve state 
choices, provided that they meet the criteria of the Clean Air Act. In 
this context, in the absence of a prior existing requirement for the 
State to use voluntary consensus standards (VCS), EPA has no authority 
to disapprove a SIP submission for failure to use VCS. It would thus be 
inconsistent with applicable law for EPA, when it reviews a SIP 
submission, to use CS in place of a SIP submission that otherwise 
satisfies the provisions of the Clean Air Act. Thus, the requirements 
of section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (15 U.S.C. 272 note) do not apply. As required by section 3 
of Executive Order 12988 (61 FR 4729, February 7, 1996), in issuing 
this proposed rule, EPA has taken the necessary steps to eliminate 
drafting errors and ambiguity, minimize potential litigation, and 
provide a clear legal standard for affected conduct. EPA has complied 
with Executive Order 12630 (53 FR 8859, March 15, 1988) by examining 
the takings implications of the rule in accordance with the ``Attorney 
General's Supplemental Guidelines for the Evaluation of Risk and 
Avoidance of Unanticipated Takings'' issued under the executive order. 
This proposed rule does not impose an information collection burden 
under the provisions of the Paperwork Reduction Act of 1995 (44 U.S.C. 
3501 et seq.).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Particulate 
matter.

    Dated: June 22, 2001.
Keith Takata,
Acting Regional Administrator, Region IX.
[FR Doc. 01-16439 Filed 6-28-01; 8:45 am]
BILLING CODE 6560-50-U
```