Promulgation of Federal Implementation Plan for ArizonaPhoenix Moderate Area PM-10; Disapproval of State Implementation Plan for ArizonaPhoenix Moderate Area PM-10

Federal RegisterApr 1, 1998

Ask Donna

What actually matters in this document.

Text

SUMMARY: Under the authority of section 110(c)(1) of the Clean Air Act

(CAA or ``the Act''), EPA today proposes a federal implementation plan

(FIP) to address the moderate area PM-10 requirements for the Phoenix

PM-10 nonattainment area. Specifically, for both the annual and 24-hour

PM-10 standards, EPA is proposing a demonstration that reasonably

available control measures (RACM) will be implemented as soon as

possible, a demonstration that it is impracticable for the area to

attain the standards by the statutory attainment deadline and a

demonstration that reasonable further progress (RFP) is being met.

Pursuant to a court order, EPA's final FIP must be signed by the EPA

Administrator no later than July 18, 1998.

As part of its proposed RACM demonstration, EPA is proposing a

fugitive dust rule to control PM-10 emissions from vacant lots, unpaved

parking lots and unpaved roads, and is also proposing an enforceable

commitment to ensure that RACM for agricultural sources will be

proposed by September 1999, finalized by April 2000 and implemented by

June 2000.

In addition, in today's document, EPA is withdrawing a 1996

proposal to restore its approval of the RACM, RFP and impracticability

demonstrations in Arizona's moderate area PM-10 plan for the annual PM-

10 standard for Phoenix and is proposing to disapprove the

impracticability and RACM demonstrations because those demonstrations

do not adequately address the CAA's moderate area PM-10 requirements.

EPA recently established a new standard for PM-2.5 and also revised

the PM-10 standards; however, today's proposal does not address these

new standards.

DATES: Written comments will be accepted until May 18, 1998. EPA is

scheduled to hold a public workshop followed by a public hearing at the

following time:

Phoenix PM-10 Moderate Area FIP Workshop and Hearing

Thursday, April 16, 1998, Workshop, 9 a.m. to 11 a.m.

Hearing, Day Session--12 noon to 4:30 p.m., Evening Session--Convenes

at 7 p.m.

ADDRESSES: Written comments on the EPA's proposed FIP and SIP actions

must be received by EPA at the address below on or before May 18, 1998.

Comments should be submitted (in duplicate, if possible) to: EPA Region

9, 75 Hawthorne Street (AIR2), San Francisco, CA 94105, Attn. Eleanor

Kaplan, (Phone: 415-744-1287).

The public workshop and public hearing will be held at the Phoenix

Corporate Center Auditorium, 3003 North Central Avenue, Phoenix,

Arizona.

A copy of docket No. A-09-98, 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 Eleanor Kaplan (415) 744-1159 to

inspect the docket at EPA's San Francisco office on weekdays between 9

a.m. and 4 p.m.

A copy of docket no. A-09-98 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.

FOR FURTHER INFORMATION CONTACT: For questions and issues regarding the

proposed measure for agricultural fields and aprons contact John

Ungvarsky (415) 744-1286; for questions and issues regarding the

proposed rule for vacant lots, unpaved parking lots and unpaved roads

contact Karen Irwin (415) 744-1903; for other general FIP and SIP

questions and issues contact Doris Lo (415) 744-1287.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Executive Summary

A. Background

B. FIP Proposal

C. Public Involvement in the FIP Process

II. Background

A. Clean Air Act Requirements

1. Designation and Classification

2. Moderate Area Planning Requirements

3. Federal Implementation Plan Provisions

4. Indian Reservations

a. EPA's FIP Obligation

b. EPA and Tribal CAA Authority in Indian Country

B. History of Arizona's PM-10 Plans and Related EPA Actions

1. Arizona's Moderate Area PM-10 Plan

2. The Microscale Plan--the 24-hour Standard

3. EPA Actions on Arizona's Moderate Area PM-10 Plan Post-Ober

With Respect to the Annual Standard

C. History of PM-10 FIP Litigation in Phoenix

III. SIP Actions

A. Proposed Disapproval of Moderate Area Plan

B. Withdrawal of Proposal to Restore Moderate Area Plan

Demonstrations for the Annual PM-10 Standard

IV. Moderate Area PM-10 Planning Requirements for the FIP Proposal

A. Attainment/Impracticability Demonstration

B. RACM/RACT Demonstration

C. Reasonable Further Progress Demonstration

V. Summary of EPA's FIP Proposal

A. RACM/RACT Demonstration

1. RACT and PM-10 Precursors

a. RACT

b. PM-10 Precursors

2. RACM Approach

3. Federal Implementation Criteria

a. Applicability to the Phoenix Area

b. Existing RACM

c. Legal Authority

4. Application of Federal Implementation Criteria

5. RACM Criteria

a. De Minimus Source

b. Technological Feasibility

c. Cost of Implementation

6. Application of RACM Criteria

7. Proposed FIP measures

a. Commitment for Agricultural Sector

(1) Summary of Proposed Commitment and Approach

(2) Background

(3) RACM Analysis

(4) Proposed Commitment

(i) Discussions With Stakeholders

(ii) BMP Approach

(iii) FIP Proposal

(5) FIP Replacement

b. Rule for Unpaved Parking Lots, Unpaved Roads and Vacant Lots

(1) Summary of Proposed Rule

(2) Discussion

(3) Compliance Approach

(4) Replacement of FIP Rule

B. Impracticability Demonstration

1. Annual Standard

2. 24-hour Standard

C. Reasonable Further Progress (RFP) Demonstration

1. Annual Standard

2. 24-hour Standard

a. Gilbert Monitoring Site

b. West Chandler Monitoring Site

VI. Impact on Tribal Reservations

VII. Administrative Requirements

A. Executive Order (E.O.) 12866

B. Regulatory Flexibility Analysis

1. Regulatory Flexibility Act Requirements

2. RFA Analysis

a. Proposed Federal Rule for Unpaved Roads, Unpaved Parking

Lots, and Vacant Lots

[[Page 15921]]

b. Proposed Federal Commitment for Agriculture

c. Certification

C. Unfunded Mandates Reform Act (UMRA)

D. Paperwork Reduction Act

I. Executive Summary

A. Background

The Phoenix area violates both the annual and 24-hour national

health-based standards for particulate matter with diameters of 10

microns or less. Consequently, Maricopa County residents continue to

breathe unhealthy air. Particulate matter affects the respiratory

system and can cause damage to lung tissue and premature death. The

elderly, children, and people with chronic lung disease, influenza, or

asthma are especially sensitive to high levels of particulate matter.

EPA recently established a new standard for particulate matter of

diameters of 2.5 microns or less and also revised the PM-10 standards;

however, today's proposal does not address these new standards.

The primary cause of the PM-10 problem is dust on paved roads

kicked up by vehicle traffic, and windblown dust from construction

sites, earth moving operations, unpaved parking lots and roads,

disturbed vacant lots, agricultural fields and aprons, and other

disturbed areas.

When an area violates a health-based standard, the Clean Air Act

(CAA) requires that the area be designated as nonattainment for that

pollutant. Phoenix was originally designated and classified as a

moderate nonattainment area for particulate matter, and Arizona was

required to develop a plan that put into place a basic set of control

measures. These measures did not adequately control the particulate

pollution problem. When the area failed to attain the standards in 1994

it was reclassified as a serious nonattainment area, and the State is

now required to develop a plan with more comprehensive control

measures.

Despite the fact that the State is now working on its serious area

plan, EPA is under court order, as a result of a lawsuit by the Arizona

Center for Law in the Public Interest (ACLPI), to develop a moderate

area federal implementation plan (FIP) for the Maricopa area. EPA is

required to prepare this FIP because the State does not have an

approved moderate area plan. Under the court order, EPA has until March

20, 1998, to propose and July 18, 1998, to finalize the FIP.

EPA has determined that not all the basic controls on sources

contributing to violations of the particulate standards are in place.

While the State has implemented a number of measures including controls

on construction and earth moving operations, as well as a vehicle

emission inspection and maintenance program and a clean burning

gasoline program, there remains a need for additional emissions

reductions. Having considered its authority and resource constraints,

EPA is proposing two measures in the FIP for the control of dust from

unpaved roads, parking lots, and vacant lots and agricultural fields

and aprons. These measures will contribute to the eventual attainment

of both the annual and 24-hour PM-10 standards.

The State intends to submit its serious area particulate plan in

the summer of 1998. If the plan includes control measures for the

sources covered by the FIP and those measures are approved by EPA, the

Agency will be able to withdraw the final FIP measures. EPA will

continue working with the appropriate State and local agencies, as well

as the agricultural community and the cities in the metropolitan area,

to replace the FIP measures with State measures. EPA believes that

clean air is likely to be achieved faster, and in greater harmony with

local economic and community goals, if its role as a backstop is

minimized by effective State and local actions. Because of the

willingness of the State and local communities to identify and pursue

solutions to their air quality problems, as evidenced by the Governor's

Air Quality Strategies Task Force, EPA expects successful State and

local action.

B. FIP Proposal

EPA's FIP proposal includes a fugitive dust rule and an enforceable

commitment in regulatory form to implement control measures for

agricultural PM-10 sources by July 2000. These are discussed in more

detail below. During the development of these measures, EPA held

numerous meetings with the affected community. The purpose of these

meetings was not only to inform the public of EPA's FIP obligation and

the need for the Agency to develop an adequate moderate area PM-10

plan, but also to help EPA craft air quality rules that meet both the

public health and economic needs of this area. During all of these

discussions there was an ongoing dialogue regarding what would be

needed to replace the FIP with appropriate State measures. EPA

appreciates the information that was provided by the community during

the development phase of the proposed FIP, and the Agency will continue

to work with the community in the development of the State's serious

area plan. EPA is hopeful that the local planning effort will result in

an approvable SIP that will allow EPA to withdraw its FIP.

Fugitive Dust Rule

Although EPA has approved a Maricopa County rule (MCESD Rule 310)

which requires controls for unpaved roads, unpaved parking lots and

vacant lots, the County is not adequately enforcing its rule for these

three sources due to lack of resources. Therefore, EPA has developed a

FIP rule that proposes specific controls that will ensure adequate

enforcement for these sources. For each source category, the FIP rule

includes three to four control measure options and allows submittal of

alternative control measures subject to EPA approval. In addition to

the FIP rule, EPA is addressing the resource issue by providing

additional inspection resources to MCESD through a CAA section 105

grant. These resources will be used by the County to verify compliance

with the FIP rule. In order to remove the FIP requirement, MCESD will

have to submit to EPA a credible implementation strategy for Rule 310,

including the provision of the additional inspection and enforcement

resources needed to ensure implementation of its rule. Individual

cities can reduce the scope of the FIP once EPA has approved ordinances

submitted as SIP revisions that eliminate and/or control these sources.

Enforceable Commitment for Agriculture

As mentioned above, EPA has approved Maricopa County Rule 310 which

requires control of fugitive dust sources, including agricultural

sources. However, MCESD is not ensuring adequate enforcement of the

rule for agricultural fields and aprons. Therefore, EPA has developed

an enforceable commitment in regulatory form for the FIP that requires

EPA to propose controls on agricultural sources by September 1999 and

implement these controls by July 2000. In discussions with key

stakeholders, general agreement was reached that these controls will be

in the form of best management practices. EPA believes that this

approach will ensure successful dust control in Maricopa's unique

environment. In order to remove the FIP requirements, the State will

need to submit and received approval of a SIP measure that replaces the

enforceable commitment. EPA is working closely with the regulatory

agencies and the agricultural community to accomplish this goal.

[[Page 15922]]

Tribal Issues

There are three Indian reservations located within the Phoenix

nonattainment area and which therefore could be considered subject to

the FIP. However, since this FIP is designed to fill a gap that exists

in the State plan, and the State plan does not apply to sources within

Indian country, EPA has decided it is inappropriate to include the

Indian reservations in this FIP. All three tribes have expressed an

interest in developing air quality programs. EPA will develop the data,

in cooperation with the tribes, that is needed to properly assess

whether controls are required to attain the standards. EPA will ensure

that controls are implemented either through EPA-approved tribal

measures or, if necessary, federal measures.

C. Public Involvement in the FIP Process

Each area has its own unique qualities and concerns. EPA can fully

understand those concerns, and plans to take them into account, through

direct participation by the affected community; therefore, in addition

to the meetings that EPA has already had with the Phoenix community,

there will be additional opportunities for public input. EPA wants to

make the final plan a product of local involvement and consensus. EPA

believes strongly that it can best fulfill the goal of the Clean Air

Act--that is, clean and healthy air for everyone--and meet the Agency's

court-ordered obligations by preparing this plan with the input of the

local community.

After this proposed action is signed and published in the Federal

Register, EPA will hold a workshop and public hearing on April 16, 1998

in the City of Phoenix. The workshop will provide an opportunity for

EPA to explain to the community why it is imposing this FIP, what

measures are included in this FIP, and who will potentially be impacted

by the FIP. The workshop will also provide the community the

opportunity to ask questions of EPA, and to make suggestions with

respect to its proposed action. The public hearing will follow the

workshop. During the public hearing, EPA will be taking formal comment

on the FIP proposal. The public comment period will begin upon

publication of the FIP proposal and will remain open for 30 days

following the public hearing, or until May 18, 1998. EPA encourages

everyone who has an interest in this proposed action to comment upon

it. EPA will consider all comments received during the public comment

period.

II. Background

A. Clean Air Act Requirements

1. Designation and Classification

On the date of enactment of the 1990 Clean Air Act Amendments, PM-

10 areas, including portions of the pre-existing Maricopa

County1 PM-10 nonattainment area, meeting the conditions of

section 107(d) of the Act were designated nonattainment for the PM-10

national ambient air quality standards (NAAQS)2 by operation

of law. Once an area is designated nonattainment, section 188 of the

Clean Air Act (CAA) outlines the process for classification of the area

and establishes the area's attainment date. In accordance with section

188(a), at the time of designation, all PM-10 nonattainment areas were

initially classified as ``moderate'' by operation of law. 56 FR 11101

(March 15, 1991).

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

\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.

On July 18, 1997, EPA revised both the annual and the 24-hour

PM-10 standards and also established two new standards for PM, both

applying only to particulate matter up to 2.5 microns in diameter

(PM-2.5)(62 FR 38651). While the revised suite of PM standards

reflects an overall strengthening of the regulatory standard for

particulate matter, the revised 24-hour PM-10 standard, viewed by

itself, represents a relaxation of that standard. As such, for areas

such as Phoenix that had not attained the pre-existing 24-hour

standard at the time of the relaxation, CAA section 172(e) calls for

application of controls to be promulgated by EPA that are no less

stringent than would have been required for areas designated

nonattainment prior to the relaxation. While today's proposed

actions relate only to the CAA requirements concerning the 24-hour

and annual PM-10 standards, as originally promulgated in 1987, the

proposed FIP is consistent with the section 172(e) requirement.

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

A moderate area could subsequently be reclassified as ``serious''

under CAA section 188(b)(1), if, at any time, EPA determined that the

area could not practicably attain the PM-10 NAAQS by the applicable

attainment date for moderate areas, December 31, 1994. Moreover, a

moderate area would be reclassified by operation of law if EPA

determined after the applicable attainment date that, based on actual

air quality data, the area was not in attainment after that date. CAA

section 188(b)(2).

On May 10, 1996, EPA published a final reclassification of the

Maricopa County PM-10 nonattainment area as a serious PM-10

nonattainment area based on actual air quality data. 61 FR 21372.

Having been reclassified, the area is required to meet the serious area

requirements in the CAA, including a demonstration that the area will

attain the PM-10 NAAQS as expeditiously as practicable but no later

than December 31, 2001. CAA sections 188(c)(2) and 189(b).3

Pursuant to section 189(b)(2), the State of Arizona was required to

submit a serious area plan addressing both PM-10 NAAQS for the area by

December 10, 1997.4

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

\3\While the serious area PM-10 CAA requirements are referenced

periodically throughout this notice, EPA's FIP obligation, the

subject of today's proposal, relates only to the moderate area

statutory requirements.

\4\By letter dated December 11, 1997 from Russell Rhoades, ADEQ,

to Felicia Marcus, EPA, Arizona submitted revisions to the Arizona

SIP for achieving and maintaining the PM-10 NAAQS. These revisions

consist of particulate control measures in the document ``Serious

Area Committed Particulate Control Measures for PM-10 for the

Maricopa County Nonattainment Area and Support Technical Analysis,''

Maricopa Association of Governments (MAG), December 1997. On

February 6, 1998, EPA found that these measures meet the Agency's

completeness criteria as set forth at 40 CFR part 51, Appendix V,

but has not yet approved or disapproved them. Also on February 6,

1998, EPA found, pursuant to CAA section 179(a), that Arizona had

failed to submit the serious area nonattainment plan for Phoenix by

the required date. In the same rule, EPA found that Arizona had

failed to submit certain portions of the moderate area plan for the

area. 63 FR 9423 (February 25, 1998). These moderate area portions

are discussed further below.

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

2. Moderate Area Planning Requirements

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. EPA

has issued a ``General Preamble''5 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.

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

\5\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).

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

Those states containing initial moderate PM-10 nonattainment areas

were required to submit, among other things, the following provisions

by November 15, 1991:

(a) Provisions to assure that reasonably available control measures

(RACM) (including such reductions in emissions from existing sources in

the area as may be obtained through the

[[Page 15923]]

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));

(b) Provisions to assure implementation of RACT on major stationary

sources of PM-10 precursors except where EPA has determined that such

sources do not contribute significantly to exceedances of the PM-10

standards (CAA section 189(e));

(c) Either a demonstration (including air quality modeling) that

the plan will provide for attainment as expeditiously as practicable

but no later than December 31, 1994 or a demonstration that attainment

by that date is impracticable (CAA section 189(a)(1)(B));

(d) For plan revisions demonstrating attainment, quantitative

milestones which are to be achieved every 3 years and which demonstrate

reasonable further progress (RFP), as defined in section 171(l), toward

attainment by the applicable attainment date (CAA section

189(c));6 and

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

\6\As will be seen below, the proposed PM-10 FIP for the

Maricopa area does not demonstrate attainment by the applicable

attainment deadline, but rather includes the alternative

demonstration that attainment by that date is impracticable.

Therefore, section 189(c) does not apply and is not discussed

further in this notice.

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

(e) For plan revisions demonstrating impracticability, such annual

incremental reductions in PM-10 emissions as are required by part D of

the Act or may reasonably be required by the Administrator for the

purpose of ensuring attainment of the PM-10 NAAQS by the applicable

attainment date (CAA sections 172(c)(2) and 171(1)).

Moderate area plans were also required to meet the generally

applicable SIP requirements for reasonable notice and public hearing

under section 110(l), 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.

3. Federal Implementation Plan Provisions

Section 110(c) of the CAA provides that:

(1) The Administrator shall promulgate a Federal implementation

plan at any time within 2 years after the Administrator--

(A) finds that the State has failed to make a required

submission or finds that the plan or plan revision submitted by the

State does not satisfy the minimum criteria established under

section 110(k)(1)(A),7 or

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

\7\Section 110(k)(1)(A) requires the Administrator to promulgate

minimum criteria that any plan submission must meet before EPA is

required to act on the submission. These completeness criteria are

set forth at 40 CFR part 51, Appendix V.

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

(B) disapproves a State implementation plan submission in whole

or in part, unless the State corrects the deficiency, and the

Administrator approves the plan or plan revision, before the

Administrator promulgates such Federal implementation plan.

Section 302(y) defines the term ``Federal implementation plan'' in

pertinent part, as:

A plan (or portion thereof) promulgated by the Administrator to

fill all or a portion of a gap or otherwise correct all or a portion

of an inadequacy in a State implementation plan, and which includes

enforceable emission limitations or other control measures, means or

techniques (including economic incentives, such as marketable

permits or auctions of emissions allowances).

EPA has wide-ranging authority under section 110(c) to fill in gaps

left by a State failure. EPA's authority to prescribe FIP measures is

of three types. First, EPA may promulgate any measure which it has

authority to issue in a non-FIP context. Second, EPA may invoke section

110(c)'s general FIP authority and act to cure a planning inadequacy in

any way not clearly prohibited by statute. Third, under section 110(c)

the courts have held that EPA may exercise all authority that the State

may exercise under the Act. For a more detailed discussion of these

authorities and restrictions on EPA's FIP authorities, see 59 FR 23262,

23290-23292 (May 5, 1994).

4. Indian Reservations

a. EPA's FIP Obligation. As stated above, the purpose of EPA's

proposed FIP is ``to fill all or a portion of a gap or otherwise

correct all or a portion of an inadequacy in a State implementation

plan,'' as specified in section 302(y). Because, except in the rare

special circumstances that have not been shown to apply to Arizona,

states have no jurisdiction to impose statutory or regulatory

requirements in Indian country, the gaps in the Arizona PM-10 SIP for

the Phoenix nonattainment area do not extend to tribal lands. As a

result, EPA is not required in its proposed FIP to promulgate

regulations for Indian lands within the Phoenix nonattainment area.

While EPA is not proposing to extend the provisions of the proposed FIP

to tribal lands, as discussed below, EPA and tribes, that are

determined to be eligible by EPA, are authoriized under the CAA to

protect air quality throughout Indian country.

b. EPA and Tribal CAA Authority in Indian Country. On February 12,

1998, EPA issued its final rule pursuant to CAA section 301(d)

specifying the provisions of the Act for which Indian tribes may be

treated in the same manner as states; the rule also authorizes eligible

tribes to implement their own air programs under the Act. 63 FR 7254.

In the proposed8 and final rule, EPA discusses generally the

legal basis under the CAA by which EPA and tribes are authorized to

regulate sources of air pollution in Indian country.

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

\8\See 59 FR 43956 (August 25, 1994).

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

In the rulemaking, EPA concluded that the CAA constitutes a

statutory grant of jurisdictional authority to Indian tribes that

allows them to develop air programs for EPA approval in the same manner

as states. 63 FR at 7254-7259.

EPA also concluded that the CAA authorizes EPA to protect air

quality throughout Indian country. See, e.g., CAA sections 101(b)(1),

301(a), and 502(d), (e), and (i). Therefore, EPA believes that it has

broad legal authority to provide federal protection in Indian country

when tribes choose not to develop a program, fail to adopt an adequate

program or fail to adequately implement a program. In addition, section

301(d)(4) empowers EPA to directly administer CAA requirements in any

case where EPA determines that treatment of tribes as identical to

States is inappropriate or administratively infeasible. 63 FR at 7262.

See also 59 FR at 43960.

It is EPA's policy to aid tribes in developing comprehensive and

effective air quality management programs by providing technical and

other assistance to them. EPA recognizes, however, that as it required

many years to develop state and federal programs to cover lands subject

to state jurisdiction, it will also require time to develop tribal and

federal programs to cover reservations and other lands subject to

tribal jurisdiction. 59 FR at 43961.

EPA promulgated 40 CFR 49.11 in the final Tribal rule, providing

that the Agency will promulgate a FIP within a reasonable time if

tribal efforts do not result in EPA-approved programs. 63 FR at 7273.

EPA has also undertaken an initiative to develop a comprehensive

strategy for implementing the CAA in Indian country that will

articulate specific steps the Agency will take to ensure that air

quality problems in Indian country are addressed either by EPA or the

tribes themselves. This strategy is currently in draft form. EPA

[[Page 15924]]

also intends to issue national regulations covering various categories

of air pollution sources that would apply in those situations in which

a tribe does not have an approved program. 63 FR at 7262-7264.

In the final Tribal rule, the Agency emphasizes that its strategy

for implementing the CAA in Indian country is multi-pronged, ``one

prong of which is federal implementation * * * [t]he other prongs

derive from a `grass-roots' approach in which staff in the EPA regional

offices work with individual tribes to assess the air quality problems

and develop, in consultation with the tribes, either tribal or federal

strategies for addressing the problems.'' 63 FR at 7264.9

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

\9\EPA then elaborates on this grass-roots approach by

discussing three components of the Agency's strategy: a needs

assessment, including the development of emission inventories,

outreach and communication, and training. 63 FR at 7264.

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

EPA believes that the strategy that it has developed for tribal

lands in the Phoenix nonattainment area, discussed in section VI below,

is consistent with the approach outlined above. In short, EPA intends

to provide technical and financial support to the Tribes in the area so

that they may develop their own programs if they wish to do so, and to

develop federal measures should it become necessary.

B. History of Arizona's PM-10 Plans and Related EPA Actions

1. Arizona's Moderate Area PM-10 Plan

The State of Arizona originally submitted a moderate area PM-10

plan revision to EPA on November 15, 1991. On March 4, 1992, EPA found

that the plan did not meet the Agency's completeness criteria at 40 CFR

part 51, Appendix V, in part because a proper public hearing on the

plan had not been held. Thereafter the State held another public

hearing and resubmitted the SIP revision on August 11, 1993. On

September 7, 1993 EPA found this plan to be complete. The State

submitted a revised and updated version of the plan on March 3, 1994.

See generally 59 FR 38402, 38403 (July 28, 1994).

On April 10, 1995, EPA approved the State's moderate area PM-10

implementation plan revision for the Maricopa area. 60 FR 18010. Among

other elements in that plan, EPA approved the State's RFP and RACM

demonstrations as meeting the requirements of sections 171(1),

172(c)(1), 172(c)(2), and 189(a)(1)(C) of the CAA. Based on its

approval of the RACM demonstration, EPA also proposed to approve, as

meeting the requirements of section 189(a)(1)(B), the State's

demonstration that even with the implementation of all RACM by December

10, 1993, it was impracticable for the Maricopa area to attain the PM-

10 NAAQS by December 31, 1994.10

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

\10\The reader should refer to both the proposed approval, 59 FR

38402, and the final rule, 60 FR 18010, for EPA's interpretation of

certain moderate area PM-10 requirements of the CAA and the Agency's

application of these interpretations to the State's moderate area

PM-10 plan. Those notices should also be consulted for the history

of the State's PM-10 plan submittals and EPA's actions concerning

them.

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

On May 1, 1995, the Arizona Center for Law in the Public Interest

(ACLPI) filed a petition for review of EPA's April 10, 1995 approval of

the State's moderate area PM-10 plan in the United States Court of

Appeals for the Ninth Circuit.

On May 14, 1996, the Ninth Circuit vacated EPA's approval of the

States's PM-10 moderate area plan. Ober v. EPA, 84 F.3d 304 (9th Cir.

1996). In short, the Court concluded that the State's moderate area

plan failed to address the moderate area CAA requirements for

attainment, RFP and RACM for the 24-hour standard and mandated that EPA

require the State to do so. The Court also found that EPA had failed to

provide the required opportunity for comment with respect to the RFP

and RACM demonstrations for the annual standard. In response to the

Court's opinion, EPA initiated the following actions.

2. The Microscale Plan--24-hour Standard

In the wake of the Ninth Circuit's Ober opinion, EPA considered how

to appropriately implement the Court's directive in the context of the

State's then-prevailing PM-10 planning efforts for the Maricopa area.

The Maricopa area was reclassified as a serious PM-10 nonattainment

area just days before the case was decided and, as noted above, the

State was required to submit a new PM-10 plan meeting the serious area

requirements by December 10, 1997.11 Therefore EPA had to

reconcile the Court's mandate that the State submit a plan correcting

its moderate area plan deficiencies regarding the 24-hour standard

concurrent with its responsibility to submit a plan meeting the serious

area requirements for both NAAQS.

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

\11\For the CAA serious area PM-10 plan requirements, see

section 189(b). EPA has issued an Addendum to the General Preamble

(Addendum) describing the Agency's preliminary views on how it

intends to review SIPs and SIP revisions containing serious area

plan provisions. See ``State Implementation Plans for Serious PM-10

Nonattainment Areas, and Attainment Date Waivers for PM-10

Nonattainment Areas generally; Addendum to the General Preamble for

the Implementation of Title I of the Clean Air Act Amendments of

1990,'' 59 FR 41998, 42011 (August 16, 1996).

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

EPA concluded that, given the substantial overlap of the moderate

and serious area planning requirements, it would not be in the public

interest to require the State to divert its scarce resources into two

independent planning exercises. At the same time, the Agency recognized

that timely action (i.e., prior to the serious area plan submittal

deadline of December 10, 1997) was required in order to be responsive

to the Court's mandate. Therefore EPA, in consultation with the Arizona

Department of Environmental Quality (ADEQ) and the MCESD, decided that

the State would incorporate the moderate area plan elements for the 24-

hour standard into the serious area plan, but would split that planning

effort into two related parts. Accordingly, EPA, in a September 18,

1996 letter to ADEQ, required submittal of a limited, locally-targeted

plan (microscale plan) analyzing air quality impacts at specific

monitoring sites, and meeting both the moderate and serious area

requirements for the 24-hour standard by May 9, 1997 (extended from an

original deadline of April 18) and a full regional plan meeting those

requirements for both the 24-hour and annual standards by December 10,

1997. Thus, the microscale and regional plans taken together would

satisfy both the moderate area requirements mandated by the Court and

the serious area planning requirements for both standards.

The State submitted the microscale plan to EPA on May 9, 1997 and

on August 4, 1997, EPA approved the following portions of the plan:

(1) under sections 172(c)(1), 189(a)(1)(C) and 189(b)(1)(B), the

provisions for implementing RACM and best available control

technology (BACM) for the significant source categories of disturbed

cleared areas, earth moving, and industrial haul roads; and

(2) under sections 189(a)(1)(B), 189(b)(1)(A), and 189(c), the

attainment and RFP demonstrations for the Maryvale and Salt River

monitoring sites.

(3) the resolution by the County of Maricopa to improve the

administration of Maricopa County's fugitive dust control program

and to foster interagency cooperation (adopted May 14, 1997);

(4) the resolutions of intent to work cooperatively with

Maricopa County to control the generation of fugitive dust pollution

adopted by the Cities of Phoenix (April 9, 1997), Tempe (March 27,

1997), Chandler (March 27, 1997), Glendale (March 25, 1997),

Scottsdale (March 31, 1997), and Mesa (April 23, 1997) and the Town

of Gilbert (April 15, 1997); and

(5) MCESD's Rule 310 (Open Fugitive Dust Sources), Rule 311

(Particulate Matter from

[[Page 15925]]

Process Industries) and Rule 316 (Nonmetallic Mineral Mining and

Processing).

In the same action, EPA disapproved the following provisions of the

State's microscale plan:

(1) under sections 172(c)(1), 189(a)(1)(C) and 189(b)(1)(B), the

provisions for implementing RACM and BACM for the significant source

categories of agricultural fields, agricultural aprons, vacant

lands, unpaved parking lots, and unpaved roads; and

(2) under sections 189(a)(1)(B), 189(b)(1)(A), and 189(c)(1),

the attainment and RFP demonstrations at the West Chandler and

Gilbert monitoring sites.12

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

\12\See EPA's proposed and final actions on the State's

microscale plan at 62 FR 31025 (June 6, 1997) and 62 FR 41856

(August 4, 1997).

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

3. EPA Actions on Arizona's Moderate Area PM-10 Plan Post-Ober With

Respect to the Annual Standard

In response to the Ober decision, EPA provided an opportunity for

public comment on the State's justifications for rejecting certain

measures as RACM and on the emission reduction credit granted by the

Agency for Rule 310 as it related to the State's RFP demonstration. EPA

also proposed to restore its approval of the RACM, RFP and

impracticability demonstrations in the State's moderate area plan with

respect to the annual PM-10 standard. 61 FR 54972 (October 23, 1996).

As a result of the extensive technical work associated with the

State's microscale plan, EPA has concluded, as discussed in detail in

section III below, that it is no longer appropriate to restore its

approval of the demonstrations in the State's moderate area plan for

the annual standard. Therefore, EPA is proposing to withdraw its 1996

proposal and, instead, is now proposing to disapprove the

impracticability and RACM demonstrations in that plan.

C. History of PM-10 FIP Litigation in Phoenix

On June 28, 1994, ACLPI filed, on behalf of two Phoenix residents,

a complaint, No. CIV 94-1318 PHX PGR, in the United States District

Court for the District of Arizona alleging that EPA was required,

pursuant to section 110(c) of the CAA, to have promulgated a moderate

area PM-10 FIP for Phoenix by March 4, 1994, two years after EPA's

finding that the State's moderate area plan was incomplete. ACLPI

sought, among other things, an order requiring EPA to promulgate a

final FIP in 12 months. On February 28, 1995, the district court

approved a consent decree requiring EPA to take final action on the

moderate area plan by March 1, 1995. If EPA approved the plan, as

turned out to be the case, the district court action would be stayed

pending appellate review.

On May 1, 1995, ACLPI filed a petition for review of EPA's April

10, 1995 approval of Arizona's moderate area PM-10 plan for the Phoenix

area in the United States Court of Appeals for the Ninth Circuit. Ober

v. EPA, No. 95-70352. On May 14, 1996, the Court issued its opinion in

the Ober case vacating EPA's approval of the State's plan.13

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

\13\The reader is referred to the text of the opinion for the

Court's disposition of the range of issues raised by ACLPI in its

petition. See 84 F.3d 304 (9th Cir. 1996). See also 61 FR 54972 in

which EPA preliminarily addresses the Court's opinion as it relates

to the RACM, RFP and attainment demonstrations for the annual

standard and 62 FR 31025 in which EPA discusses the opinion as it

relates to the required demonstrations for the 24-hour standard.

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

As a result of the Ninth Circuit's opinion in Ober, the stay of

proceedings in the district court FIP case was lifted. On November 29,

1996 and March 25, 1997, respectively, the court approved a second

consent decree and a modified second consent decree in which EPA agreed

that if the Agency disapproved the State's microscale plan in whole or

in part, the Administrator is required to sign by March 20, 1998 a

Notice of Proposed Rulemaking (NPRM) that sets forth a proposed FIP for

Phoenix that meets the moderate area PM-10 requirements for the annual

and 24-hour standards for attainment, RACM and RFP as set forth in CAA

sections 189(a)(1)(B) and (C), and 172(c)(2) or 189(c)(1). Under the

decree, EPA must sign a Notice of Final Rulemaking (NFRM) setting forth

the final FIP by July 18, 1998. EPA's FIP obligation is relieved as to

any portion of the plan for which EPA signs a NFRM approving corrective

SIP revisions by July 18, 1998.

III. SIP Actions

A. Proposed Disapproval of Moderate Area Plan

In its July 28, 1994 proposed approval of the State's moderate area

plan, EPA noted that the plan's emission inventory identified fugitive

dust sources as contributing more than 50 percent of the PM-10

emissions in the Phoenix area. These fugitive dust sources included,

but were not limited to, construction and demolition activities,

farming operations, uncovered haul trucks, and emissions from unpaved

roads. 59 FR 38405. EPA also stated that it believed that Maricopa

County's fugitive dust rule, Rule 310, fully addressed fugitive dust

sources in the area. 59 FR 38404. Based in part on this belief and its

evaluation of the balance of RACM in the plan, EPA proposed and

eventually found that the moderate area plan assured timely

implementation of RACM, and that these RACM were sufficient to

demonstrate RFP but were insufficient to demonstrate attainment by the

moderate area deadline of December 31, 1994. EPA, therefore, approved

the RACM, RFP, and impracticability demonstrations in the State's

moderate area plan. 60 FR 18010.

As discussed above, EPA's approval of the moderate area plan was

subsequently vacated in Ober. In October 1996, EPA proposed to restore

its approval of the RACM, RFP and impracticability demonstrations in

the State's moderate area plan for the annual standard. 61 FR 54972.

This proposal was based, in part, on the Agency's continued belief that

Rule 310 represented RACM for fugitive dust sources in Maricopa County.

As described previously, EPA subsequently approved in part and

disapproved in part the State's microscale plan for the 24-hour

standard. In its evaluation of the microscale plan, EPA found that, in

fact, Rule 310, due to inadequate commitment of resources by the State,

does not assure enforcement of RACM on a number of fugitive dust

sources, including unpaved roads and unpaved parking lots, that are

legally subject to the rule. In addition, EPA found that there were no

RACM that applied for agricultural sources. 62 FR 41862.

While these findings were made in the context of evaluating RACM

for the 24-hour standard, the findings also apply to the annual

standard. As noted above, EPA's 1994 approval of the State's moderate

area plan relied in large part on the Agency's finding that Rule 310

constituted RACM for fugitive dust sources. As a result of its findings

with respect to the microscale plan, EPA no longer considers Rule 310

to satisfy the Act's requirement for enforceable RACM for fugitive dust

sources not permitted by the County under the rule; therefore, since

the Agency can no longer find that the State's moderate area plan

assures the required source compliance with Rule 310 and, hence, does

not ensure enforcement of RACM as required by the Act, EPA, is

proposing to disapprove the RACM demonstration for the annual standard

in the State's moderate area plan.

In order for a moderate area plan to demonstrate that attainment is

impracticable, it must make that showing in light of implementation of

all RACM. 57 FR 13544. Since EPA is now proposing to disapprove the

RACM

[[Page 15926]]

demonstration in the State's moderate area plan, the Agency is also

proposing to disapprove the demonstration contained in that plan that

attainment by the moderate area deadline of December 31, 1994 was

impracticable.14

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

\14\The discussion in section IV.A. regarding EPA's views of the

status of the CAA's moderate area attainment requirements following

an area's reclassification to serious is applicable here and the

reader is referred to that section.

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

EPA, however, is not proposing to disapprove the RFP demonstration

in the State's moderate area plan. The estimated emission reductions

from the implementation of Rule 310 on unpermitted sources accounted

for less than 20 percent of the total emission reductions from the

plan. Even without the reductions from the unpermitted sources, EPA

believes that plan still contains sufficient emission reductions from

other measures to demonstrate RFP for the annual standard and,

therefore, disapproval is not warranted. This issue, however, is

academic since, as noted before, EPA is withdrawing its proposal to

restore approval of the RFP demonstration for the annual standard in

the State's plan and is substituting its own proposed RFP demonstration

for that standard.

B. Withdrawal of Proposal to Restore Moderate Area Plan Demonstrations

for the Annual PM-10 Standard

As a consequence of the proposed disapprovals discussed above, EPA

is today withdrawing its October 26, 1996 proposal (61 FR 54972) to

restore the Agency's approval of the RACM and impracticability

demonstrations for the annual standard in the State's moderate area

plan.

EPA is today also withdrawing its proposal to restore approval of

the RFP demonstration for the annual standard in the State's plan.

While EPA continues to believe that the plan as a whole continues to

demonstrate RFP, its previous analysis of the State's RFP demonstration

is no longer valid because it relied in part upon emission reductions

from the implementation of Rule 310 on a number of unpermitted source

categories. Under its CAA section 110(c) authority, EPA is proposing

its own RFP demonstration for the annual standard as described in

section V.C.

IV. Moderate Area PM-10 Planning Requirements for the FIP Proposal

A. Attainment/Impracticability Demonstration

Because the moderate area attainment deadline, December 31, 1994,

has passed, EPA is confronted with the issue of how to define the

moderate area requirements applicable to the Agency's proposed FIP. EPA

believes that because the Maricopa area was reclassified from a

moderate to a serious nonattainment area, the moderate area

requirements (demonstration of impracticability or attainment by no

later than December 31, 1994) have been superseded by the serious area

attainment requirement (attainment by no later than December 31, 2001)

and are therefore now moot. Having reviewed the CAA's moderate and

serious area PM-10 attainment provisions, EPA has concluded that when a

moderate PM-10 area has been reclassified after the moderate area

attainment deadline has passed and been replaced with a new deadline,

the moderate area deadline no longer has any logical, practical or

legal significance.

Thus, under this interpretation, there would be no need for the

proposed FIP, to the extent that it is intended to meet the CAA's

moderate area requirements, to demonstrate attainment. In other words,

such an attainment demonstration would only be required when the State

submits its complete serious area plan to comply with the section

189(b)(1) attainment demonstration requirement. EPA believes that its

interpretation can be reconciled with the Ober Court's directive that

EPA require the State to address the moderate area attainment

requirements for the 24-hour standard and that such an interpretation

is reasonable given the legal and factual context in which that case

was decided. EPA's reasoning is explained in detail at 61 FR 54972,

54974-54975 (October 23, 1996). Nevertheless, EPA complied with the

Court's remedies regarding the moderate area attainment requirements by

directing the State to meet those requirements in the microscale

plan.15 Having complied with the Court opinion by directing

that the State meet the moderate area attainment requirements in its

planning efforts, EPA discerns no basis for applying different

requirements to the Agency in promulgating a moderate area FIP that is

intended to correct State planning deficiencies.

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

\15\While EPA could have sought clarification on this issue from

the Ninth Circuit, the Agency did not do so because such a review

would necessarily have occurred without benefit of a thorough

briefing on the issue and in the absence of an administrative

record. The Agency does, however, reserve its right to assert its

interpretation in any challenge to EPA's implementation of the

Court's remedies or in the context of other reclassifications.

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

Having determined that the proposed FIP must meet the CAA's

moderate area attainment requirements, EPA has concluded that since the

December 31, 1994 deadline has passed and the Maricopa area has been

reclassified, the only attainment deadline currently applicable to the

area is the serious area deadline, that is, achievement of attainment

as expeditiously as practicable, but no later than December 31, 2001.

Thus, consistent with the terms of section 189(a)(1)(B), the moderate

FIP must either demonstrate attainment of the PM-10 NAAQS as

expeditiously as practicable but no later than December 31, 2001, or,

alternatively demonstrate that attainment by that date is

impracticable.

B. RACM/RACT Demonstration

Sections 172(c)(1) and 189(a)(1)(C) read together require that

moderate area PM-10 plans include RACM and RACT for existing sources of

PM-10. These plans were to provide for implementation of RACM/RACT no

later than December 10, 1993. Since the moderate area deadline for the

implementation of RACM/RACT has passed, EPA has concluded that the

RACM/RACT required in the FIP 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).

The methodology for determining RACM/RACT is described in detail in

the General Preamble. 57 FR 13498, 13540-13541. In summary, EPA

suggests starting to define RACM with the list of available control

measures for fugitive dust, residential wood combustion, and prescribed

burning contained in Appendices C1, C2, and C3 of 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 for attainment in

the area. 57 13498, 13560.

In addressing cost issues, the General Preamble suggests that in

case of public sector sources and control measures, the cost evaluation

should consider the impact of the reasonableness of the measures on the

governmental entity that must bear the responsibility for their

implementation. 57 FR 13541.

The General Preamble does not define ``de minimis'' except to say

that it would be unreasonable to apply

[[Page 15927]]

controls to sources that are negligible contributors to ambient

concentrations. 57 FR 13540, footnote 18. The regulatory scheme for PM

in subpart 4 of the CAA establishes two graduated levels of controls,

RACM and BACM, depending on the severity of the area's air quality. See

CAA section 189(a) and (b). These statutory requirements, applicable to

moderate and serious areas, respectively, clearly contemplate that

smaller PM sources need not, in the first instance, bear the burden of

emission reductions. Thus, in determining the initial level of control,

it is appropriate to focus on what is reasonable and practicable for

significant sources of PM emissions.

For its proposed FIP, EPA is proposing to rely on the criteria

applied to define significant contributors under its new source

permitting programs (40 CFR 51.165(b)) as a surrogate for determining

which source categories require the application of RACM. Under EPA's

new source permitting programs, a PM-10 source is considered to be a

``significant contributor'' if it contributes 5 g/m\3\ or more

of PM-10 to a location of expected 24-hour exceedances and 1

g/m\3\ or more to a location of expected annual violation.

Therefore, a de minimis source category for the purposes of defining

which source categories require the application of RACM under section

189(a)(1)(C), is proposed to be one that contributes less than 5

g/m\3\ of PM-10 to a location of expected 24-hour exceedances

and less than 1 g/m\3\ to a location of expected annual

violations.

It should be emphasized that the de minimis criterion is invoked

solely for the purposes of determining which source categories need

RACM and not for determining which source categories need controls for

attainment. In establishing this RACM de minimis criterion, EPA is not

taking the position that de minimis RACM source categories can escape

controls if such controls are needed for attainment or RFP. In that

case, it is the Agency's position that the level of control on such

insignificant sources need only be at the level required to demonstrate

reasonable further progress and expeditious attainment and that this

level need not be justified under section 189(a)(1)(C) as RACM.

For any RACM that EPA rejects for reasons of technology, cost, size

of source category or timing of implementation as described above, the

Agency must provide a reasoned justification for the rejection. Once

the final list of RACM is defined, each RACM must be converted into a

legally enforceable vehicle such as a rule, permit, or other

enforceable document. 57 FR 13498, 13541.

C. Reasonable Further Progress (RFP) Demonstration to Follow

EPA has concluded that for PM-10 plans that demonstrate that it is

impracticable for an area to attain the NAAQS by the applicable

attainment date, the governing statutory requirement for RFP is section

172(c)(2) as defined by section 171(l).16 Section 172(c)(2)

of the Act states that nonattainment plans shall require reasonable

further progress (RFP). RFP is defined in section 171(1) as ``such

annual incremental reductions in emissions of the relevant air

pollutant as are required by this part [D] or may reasonably be

required by [EPA] for the purpose of ensuring attainment of the

applicable [NAAQS] by the applicable date.''

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

\16\EPA originally set forth preliminary guidance on the RFP

requirements for such plans in its final rule approving the Arizona

moderate area PM-10 plan for the Phoenix area. See 60 FR 18010,

18013. The Agency subsequently clarified portions of that guidance

in its proposal to restore the annual standard demonstrations in the

State's moderate area plan following the Ninth Circuit's Ober

decision. See 61 FR 54972, 54973-54974. The reader is referred to

these notices for an expanded discussion of the Agency's

interpretation of the RFP requirements for moderate PM-10 areas

demonstrating impracticability.

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

EPA has interpreted the RFP requirement for areas demonstrating

impracticability as being met by a showing that the implementation of

all RACM has resulted in incremental emission reductions below pre-

implementation levels. EPA believes that this interpretation is

consistent with the definition in section 171(l) and with the statutory

term ``reasonable further progress.''

V. Summary of EPA's FIP Proposal

As a moderate area plan, EPA's proposed FIP must demonstrate

attainment of both the annual and 24-hour PM-10 standards by December

31, 2001 (as a result of the passing of the moderate area deadline and

the reclassification to serious) and provide for expeditious

implementation of RACM for all significant source categories, or

demonstrate that even with RACM it is impracticable for the area to

attain by that date. The proposed FIP must also demonstrate RFP

consistent with the attainment or impracticability

demonstration.17

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

\17\See section IV. above.

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

EPA's FIP obligation arises only as to SIP provisions that are not

approved. As discussed previously in section II.B.2., EPA has already

approved RACM, attainment, and RFP demonstrations for certain sources

of source categories in the Phoenix area. Specifically, EPA has already

approved RACM for disturbed cleared areas (e.g., construction sources),

earth moving, industrial haul roads, and stationary sources and the

attainment and RFP demonstrations for the 24-hour standard at the

Maryvale and Salt River monitoring sites. 62 FR 41856. As a result,

this proposed FIP does not address these SIP elements.

EPA, however, has disapproved the State's RACM demonstrations for

the significant source categories of unpaved roads, unpaved parking

lots, vacant lots, and agricultural fields and aprons as well as its

attainment and RFP demonstrations for the 24-hour standard at the

Gilbert and West Chandler monitoring sites. 62 FR 41856. In addition,

EPA is proposing to disapprove the RACM and attainment/impracticability

demonstrations for the annual standard in the State's moderate area

plan and to revise the State's RFP demonstration for this

standard.18 See Section III.A.

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

\18\ EPA's FIP obligation was initially triggered by an

incompleteness finding on the State's moderate area plan submittal.

Although EPA subsequently determined the submittal to be complete,

the FIP obligation continues until there is a fully approved SIP in

place.

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

The following sections describe EPA's proposals to address each of

the outstanding elements of the Phoenix moderate plan: RACM/RACT

demonstration, attainment/impracticability demonstrations, and RFP

demonstrations.

A. RACM/RACT Demonstration

1. RACT and PM-10 Precursors

a. RACT. In the General Preamble, EPA recommends that major

stationary sources of PM-10 be the starting point for a reasonably

available control technology (RACT) analysis. 57 FR 13541. Stationary

sources of PM-10 in the Phoenix area include power plants, concrete

manufacturing, sand and gravel operations, and cotton ginning. MCESD

has adopted regulations requiring RACT for stationary sources of PM-10:

Rule 311, ``Particulate Matter from Process Industries,'' and Rule 316,

``Nonmetallic Mineral Mining and Processing.'' These measures were

approved by EPA in 1995 as RACT for PM-10 stationary sources as part of

the moderate area plan approval. 60 FR 18009. While not at issue in the

litigation regarding that plan's approval, EPA's approval of these

rules was also incidentally vacated by the Ober decision. The Agency

restored these RACT rules to the SIP as part of its action on the

microscale plan. 62 FR 41862.

[[Page 15928]]

b. PM-10 Precursors. Under CAA section 189(e), the control

requirements applicable to major stationary sources of PM-10 must also

be applied to major stationary sources of PM-10 precursors, unless EPA

determines such sources do not contribute significantly to PM-10 levels

in excess of the NAAQS in the area. ``Significantly'' is not defined in

either the Act or in the General Preamble. Rather, for moderate areas,

the determination is to be made on a case-by-case basis. 57 FR at

13539. For this action, EPA proposes to rely on the criteria applied

under its new source permitting programs (40 CFR 51.165(b)) to guide

its review of whether major stationary sources of PM-10 precursors

significantly contribute to PM-10 levels in excess of the standard. See

Section IV.B. A major stationary source in a moderate area is one that

emits or has the potential to emit 100 tons per year or more of PM-10

or a PM-10 precursor. 57 FR 13538.

PM-10 precursors can include sulfur oxides (SOX),

nitrogen oxides (NOX), ammonia, and volatile organic

compounds (VOCs). In the Phoenix area, VOCs are not important in

secondary particulate formation. Sulfur oxide emissions in the area are

dominated by emissions from non-road engines and thus major sources of

SOX account for less than 10 percent of the total inventory.

Nitrogen oxide emissions are almost entirely (90 percent) from on- and

non-road engines, with major stationary sources accounting for only 4.3

percent of the total inventory. Livestock operations (which are not

considered major point sources) account for 99.8 percent of ammonia

emissions. See Tables 2-2 and B3-1 in ``1994 Regional PM-10 Emission

Inventory for the Maricopa County Nonattainment Area,'' Draft Final

Report, MAG, May 1997. In total, major point sources account for less

than 7 percent of the total precursor inventory.

Draft PM-10 air quality modeling for the Phoenix nonattainment area

indicates that exceedances of both the 24-hour and annual standards are

attributable chiefly to direct particulate matter emissions from re-

entrained dust from paved roads and fugitive dust from disturbed

surfaces such as construction sites and agricultural fields. The draft

modeling also indicates that secondary particulate formation from all

sources of precursors (including natural background) contributes from

3.6 to 9.4 g/m\3\ to the modeled 24-hour episodes. See

``Technical Support Document for the Regional PM-10 Modeling in Support

of the 1997 Serious Area PM-10 Plan for Maricopa County Nonattainment

Area,'' Draft Report, MAG, October 1997, Table 3-26 (MAG Modeling TSD).

No contribution from secondary particulates to the annual standard was

estimated in the draft modeling; however, based on a crude average of

the results of the eight 24-hour episodes modeled, the annual total

impact (including background) of secondary particulates is around 5.6

g/m\3\.

From these modeling results, and assuming that a source's

contribution to secondary particulate levels is proportional to its

presence in the inventory, major stationary sources of PM-10 precursors

contribute no more than 0.6 g/m\3\ to the 24-hour standard and

0.3 g/m\3\ to the annual standard (the actual contribution is

likely to be less when the background levels of secondary particulates

are factored out). Both these levels are well below the 5 g/

m\3\ 24-hour standard and 1 g/m\3\ annual standard

significance levels; therefore, EPA proposes to find, based on existing

modeling, that major stationary sources of PM-10 precursors do not

contribute significantly to PM-10 levels in the Maricopa area which

exceed the PM-10 NAAQS, and therefore, RACT on these major sources is

not required under section 189(e). With this proposal, which is based

on an assessment of the current mix of sources and meteorological

patterns, EPA is not drawing any conclusions on the potential future

need or desirability of controls on major sources of PM-10 precursors

to assure eventual attainment of the PM-10 standard in the Phoenix

area.

2. RACM Approach

As discussed in section IV.B. above, EPA's General Preamble

suggests determining RACM by beginning with the list of measures found

in Appendix C to the General Preamble and adding to that list any

measures which have been suggested by public comments. Any measures

that are determined to apply to emission sources of PM-10 that are de

minimis and any measures that are technologically infeasible or have

unreasonable costs can then be culled from the list. A reasoned

justification must be provided for each measure that is rejected as

RACM. 57 FR 13498, 13540.

EPA has identified a list of 99 potential control measures. This

list of measures is taken from the list of measures developed for the

State's 1991 moderate area plan and includes the measures found in

Appendix C to the General Preamble as well as measures recommended by

the Maricopa air agencies and in public comments on the moderate area

plan.19 The measures range from fugitive dust and

transportation control measures to measures which achieve reductions

from national transportation sources such as aircraft and trains.

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

\19\The 1991 MAG plan identified 79 potential RACM with an

additional 82 potential measures identified from public comment.

Many of these public comment measures, however, duplicated measures

on the original list of 79.

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

Before evaluating measures as RACM, EPA first screened the list of

99 measures to determine which measures were applicable to the Phoenix

area and for which EPA had legal authority. EPA then screened the list

to determine which measures it has already approved as State RACM or

adopted at the federal level and considers RACM. Where EPA has already

determined a measure to be RACM, no further analysis of the measure is

necessary. Finally, the Agency evaluated the resulting shorter list of

measures based on the General Preamble's RACM criteria to identify

which measures constituted RACM for the Phoenix area.

Readers should note that the following analysis is meant to apply

only in the limited instance of this moderate area PM-10 FIP for the

Maricopa County area and only to the determination of the availability

and reasonableness of controls for adoption and implementation by EPA

and not by the State of Arizona, its local jurisdictions or other

states. In contrast to EPA's regulatory authority as a federal

executive-branch agency, the concept of ``state'' as used in the Clean

Air Act embodies both the state's executive and more extensive

legislative functions and therefore includes the authority not only to

regulate but also to establish new legal authority and to raise funds

for necessary programs. As a result, it is likely that the State could

adopt and implement a broader range of RACM.

Because there are both a 24-hour and an annual PM-10 standard, EPA

must evaluate whether each measure is reasonably available for each

standard. However, except for the de minimis criterion discussed later,

the criteria EPA used to determine potential RACM are equally

applicable to both PM-10 standards, that is, each criterion and the

results of applying the criterion to a measure do not vary depending on

whether the measure is being evaluated for the 24-hour or annual

standard. As a result, a completely separate RACM analysis for each

standard is not warranted and has not been performed.

[[Page 15929]]

3. Federal Implementation Criteria

a. Applicability to the Phoenix Area. Before a measure can be

considered as potential RACM, EPA must first determine if the measure

would have any inherent potential to reduce PM-10 emissions in the

Phoenix area. Some of the listed measures cover sources that are not

represented in the Phoenix area, such as marine vessel

operations20 and deicing materials, and were rejected from

further evaluation on this basis.

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

\20\Marine vessel operations here mean commercial port traffic

operations and not pleasure or recreational boating operations.

Emissions from pleasure/recreational boat engines are covered under

non-road engine standards.

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

In addition, many of the 99 measures were taken from the ozone or

CO air quality plans for the Phoenix area and are primarily intended to

reduce CO or ozone precursor emissions. Several of these measures do

not reduce PM-10 emissions. For example, since PM-10 emissions from

both tailpipes and re-entrained dust from paved roads are independent

of the speed of vehicles, measures that simply improve traffic flow and

thus improve overall traffic speeds have no effect on primarily-emitted

PM-10.21

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

\21\Nor do such flow improvements have a beneficial effect on

secondary particulate levels since emissions of the major PM-10

precursor from on-road motor vehicles, NOx, increase with speed.

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

Note that this criterion is not addressing whether the measure

could be implemented in the Phoenix area in a manner that would achieve

PM-10 emission reductions. Implementation feasibility will be

considered as part of the technical feasibility criterion below.

b. Existing RACM. In some instances, EPA has already SIP-approved a

measure or very similar measure as RACM or has promulgated at the

federal level a measure that it considers to be RACM. Where EPA has

already determined a measure to be RACM, no further analysis of the

measure is necessary.

c. Legal Authority. EPA must have the legal authority under the

Clean Air Act to promulgate, implement and enforce a measure, and must

not be preempted from promulgating, implementing, or enforcing it by

other federal statutes, regulations or court orders before it considers

a measure reasonably available. EPA's FIP authority under CAA section

110(c) is broad (see section II.A.3. above); however, the Agency is

constrained in specific instances by the Act itself. See e.g., CAA

section 110(a)(5)(A)(i) (prohibition on indirect source review

programs) and section 110(c)(2)(B) (prohibition on parking surcharges).

Additionally, EPA's authority to promulgate measures in a FIP which

would require the State to enact legislation or expend state funds is

limited. EPA may require the State to enact legislation or expend its

funds if the FIP measures affect the pollution-creating activities of

the State, but may not do so if the effect is to govern the pollution-

creating activities of others. For example, EPA could not require a

state to expand a mass transit system in order to reduce emissions from

private automobiles. EPA could, however, require a state to retrofit

state-owned buses to reduce emissions from those buses. For a detailed

discussion of this issue, see 52 FR 23263, 23291-23292 (February 5,

1994) (proposed ozone and CO FIP for the South Coast Air Basin).

4. Application of Federal Implementation Criteria

Table 1 provides an overview of the application of the above

federal implementation criteria to the 99 measures. Table 1 also

identifies which measures EPA has already approved as RACM or has

already promulgated a federal measure that it considers RACM (e.g.,

diesel fuel standards). Of the 99 measures, 21 were eliminated because

the sources do not exist in the Phoenix area or the measure does not

beneficially affect PM-10 emissions, 11 because EPA had already

approved or promulgated RACM, and 11 measures because EPA does not have

the legal authority to adopt and/or implement the measure.

Consequently, 56 measures were considered for inclusion in the proposed

FIP. A more detailed discussion of EPA's reasons for rejecting a

measure can be found in the Technical Support Document for today's

proposed action.

In order to evaluate its ability to implement each of these

measures, EPA had to first identify how it would implement the measure.

EPA considered three basic methods of implementation: (1) by rule

requiring the owner/operator of the source to implement the control,

(2) by direct action (e.g., EPA would pave a road), or (3) by providing

additional funding to the State or local agency to implement the

measure (e.g., expand MAG ridesharing). The implementation method(s)

assumed for a measure is indicated in Table 1 by the number in

parentheses after the description of the measure. These numbers

correspond to the numbers above.

Note: Where a measure is not applicable to the Phoenix area or

where the Agency lacks legal authority, EPA has not analyzed the

measure for the remaining criteria. This is indicated by dashes in a

column. A question mark in a legal authority column indicates that

EPA's legal authority is uncertain at this time; however, for the

purposes of this analysis, question marks are treated as yeses.

Table 1.--Measures Appropriate for Federal Implementation

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

Available

Source category and measure Appropriate No approved Legal federal

to PHX PM-10 RACM authorization measures

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

A.1. Paved Road Dust--Reduce Dust (Silt) Loading

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

1. Pave, vegetate, or chemically stabilize access

points where unpaved traffic surfaces adjoin paved

roads (1)............................................. Y Y Y Y

2. Require haul trucks to be covered (1)............... Y Y Y Y

3. Provide for traffic rerouting/rapid clean-up of

temporary sources of dust (water erosion, track out,

material spills) (1).................................. Y Y/N Y Y

4. Improved material specification for deicing

materials (1)......................................... N ............ ............. N

5 Require curbing and pave or stabilize road shoulders

(1)................................................... Y Y ? Y

6. Provide for stormwater drainage to prevent water

erosion onto paved roads (2/3)........................ Y Y ? Y

7. Mitigation of freeway construction impacts (1)...... Y Y/N Y Y

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

A.2. Paved Road Dust/Tailpipe Emissions--Reduce VMT

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

1. Implement short range transit improvements (2/3).... Y Y ? Y

2. Implement long range transit improvements (2/3)..... Y Y ? Y

[[Page 15930]]

3. Require exclusive bus lanes on arterials and

freeways (2/3)........................................ Y Y ? Y

4. Expand MAG rideshare program (2/3).................. Y Y Y Y

5. Adopt trip reduction ordinance...................... Y Y Y Y

6. Establish voluntary no drive days (2/3)............. Y Y Y Y

7. Establish an areawide public awareness program (2/3) Y Y Y Y

8. Build/establish park and ride lots (2/3)............ Y Y Y Y

9. Provide employees financial incentives (e.g., zero

bus fares) in lieu of parking (1)..................... Y Y Y Y

10. Require employers to provide preferential parking

for car and van pools (1)............................. Y Y Y Y

11. Require mandatory parking charges for employees (1) ............ ............ N N

12. Build HOV lanes on freeways (3).................... Y Y ? Y

13. Build HOV lanes on arterials (3)................... Y Y ? Y

14. Build HOV ramps which bypass metering signals (3).. Y Y ? Y

15. Promote increased bicycle use (3).................. Y Y Y Y

16. Provide or require bicycle travel (e.g., lanes) and

support facilities (e.g., lockers and racks) (3)...... Y Y ? Y

17. Promote pedestrian travel through provisions of

pedestrian facilities (e.g. sidewalks) (3)............ Y Y ? Y

18. Provide pedestrian overpasses (3).................. Y Y ? Y

19. Promote the use of/require employers to provide

alternative work hours (1)............................ Y Y Y Y

20. Promote the use of/require employers to provide

alternative work weeks (1)............................ Y Y Y Y

21. Promote the use of telecommuting (1)............... Y Y Y Y

22. Promote the use of teleconferencing (1/2/3)........ Y Y Y Y

23. Provide auto free zones and pedestrian malls (2/3). Y Y N N

24. Provide vanpool purchase incentives such as tax

breaks (1)............................................ Y Y N N

25. Require merchants to provide alternative

transportation incentives to customers (1)............ Y Y Y Y

26. Implement congestion pricing (2/3)................. Y Y N N

27. Require non-employee parking to be priced (1)...... Y Y N N

28. Impose fee on vehicles related to emissions (smog

fees) (1)............................................. Y Y Y Y

29. Encourage private sector transit by state

deregulation (1)...................................... N ............ ............. N

30. Evaluate & mitigate air quality impacts from new

development (indirect source review) (1).............. Y Y N N

31. Require increased land use density along transit

routes (1)............................................ Y Y N N

32. Provide a fee-based tradable travel permit program

(1/2)................................................. Y Y N N

33. Set up system of road pricing (2/3)................ Y Y N N

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

B. On-Road Vehicle Exhaust--Tailpipe and Non-VMT Reduction Measures

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

1. Expand current I/M to all model years (1/2/3)....... Y Y Y Y

2. Expand the current I/M program statewide (1/2/3).... Y Y Y Y

3. Expand the current I/M program countywide (1/2/3)... Y Y Y Y

4. Require the use of No. 1 diesel fuel (1)............ Y N Y N

5. Require clean fuels for fleet vehicles (1).......... Y Y Y Y

6. CA new car standards (1)............................ Y Y Y Y

7. Reduce cold start emissions (1)..................... N ............ ............. N

8. Scrap higher polluting vehicles (2/3)............... Y Y Y Y

9. Reduce idling at drive up facilities (1)............ N ............ ............. N

10. More strictly enforce traffic, parking, air

pollution regulations (2)\1\.......................... Y Y N N

11. Freeway surveillance (2/3)......................... N ............ ............. N

12. Ramp metering & signage (2/3)...................... N ............ ............. N

13. Traffic signal synchronization (1/2/3)............. N ............ ............. N

14. Reversible lanes on arterials (1/2/3).............. N ............ ............. N

15. One way streets (1/2/3)............................ N ............ ............. N

16. Truck restrictions during peak periods (1/2/3)..... N ............ ............. N

17. Intersection improvements (2/3).................... N ............ ............. N

18. On street parking restrictions (1/2/3)............. N ............ ............. N

19. Bus pullouts in curbs (1/2/3)...................... N ............ ............. N

20. Alternative fuels for buses/electric shuttle buses

(1)................................................... Y Y Y Y

21. Emission controls on public diesel vehicles (1).... Y N ............. N

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

C. Dust from Unpaved Road/Parking Lot/Disturbed Vacant Lots

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

1. Pave or otherwise stabilize permanent unpaved haul

roads, and parking or staging areas at commercial,

municipal, or industrial facilities (1)............... Y N ............. N

2. Require sources to submit dust control plans (1).... Y \2\N/Y Y Y

3. Develop traffic reduction plans on unpaved roads (1) Y Y Y Y

4. Limit use of recreational vehicles on open land (1). Y Y Y Y

5. Pave or stabilize unpaved roads (1)................. Y Y Y Y

6. Pave or stabilize unpaved parking areas (1)......... Y Y Y Y

7. Require controls on material storage piles (1)...... Y N ............. N

[[Page 15931]]

8. Require stabilization of wind erodible soils (1).... Y Y Y Y

9. Require windbreaks, watering, paving, vegetating for

windblown dust (1).................................... Y Y Y Y

10. Restrict blowers for landscaping (1)............... Y Y Y Y

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

D. Agricultural Sources

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

1. Rely on soil conservation requirements (e.g.,

conservation plans) of the Food Security Act (1)...... Y Y Y Y

2. Require windbreaks for agricultural sources (1)..... Y Y Y Y

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

E. Residential Wood Combustion (RWC)

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

1. Establish an episodic curtailment program for RWC (1/

2/3).................................................. Y N ............. N

2. Establish a public education/information program for

RWC (2/3)............................................. Y N ............. N

3. Encourage the improved performance of RWC devices

(1)................................................... Y N ............. N

4. Provide inducements to reduce number of RWC devices

(1/2/3)............................................... Y N ............. N

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

F. Other Area Sources

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

1. Develop a smoke management program for prescribed

burns (1)............................................. Y N ............. N

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

G. Point Sources

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

1. RACT for stationary sources (1)..................... Y N ............. N

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

H. Marine Vessel/Ports

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

1. Divert port related truck traffic to rail (1)....... N ............ ............. N

2. Control emissions from ship berthing facilities (1). N ............ ............. N

3. Control fugitive emissions from marine vessels (1).. N ............ ............. N

4. Control emissions from marine diesel operations (1). N ............ ............. N

5. Limit the sulfur content of marine fuel (1)......... N ............ ............. N

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

I. Locomotives

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

1. Reduce rail crossings (1)........................... Y Y N N

2. Control switching locomotives (1)................... Y Y Y Y

3. Electrify rail lines (1)............................ Y Y Y Y

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

J. Airplanes/Airport Ground Equipment

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

1. Centralized airport ground power systems (1)........ Y Y Y Y

2. Reduce emissions from airport ground access vehicles

(1)................................................... Y Y Y Y

3. Establish tighter emissions standards for new jet

engines (1)........................................... Y Y Y Y

4. Control emissions from aircraft and ground service

vehicles (1).......................................... Y Y Y Y

5. Require replacement of high emitting aircraft (1)... Y Y Y Y

6. Require general aviation vapor recovery (1)......... N ............ ............. N

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

K. Other Non-Road Engines

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

1. Establish emission standards for small utility

equipment (1)......................................... Y N ............. N

2. Establish emission standards for new heavy duty

construction equipment (1)............................ Y Y ............. Y

3. Establish emission standards for off road

motorcycles (1)....................................... Y Y Y Y

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

L. Miscellaneous Measures

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

1. Expand PM-10 monitoring network (\2/3\)............. N ............ ............. N

2. Move state fair to a different time of the year (1). N ............ ............. N

3. Winter daylight savings time (1).................... N ............ ............. N

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

\1\EPA has no legal authority to enforce local measures, such as traffic and parking regulations, which are not

approved into the SIP. Most PM-10 air pollution regulations are separately listed in this table.

\2\Dust control plans are a requirement for sources which are required to obtain a permit from the County, but

are not a requirement for unpermitted sources. A dust control plan is a method for identifying, implementing

and enforcing dust control measures for and on a particular source, rather than a dust control measure in and

of itself.

5. RACM Criteria

The General Preamble suggests three criteria for excluding measures

as RACM: de minimis source, technological infeasibility, and the cost

of control in the nonattainment area. EPA's proposed definitions for

each of these criteria are described below.

a. De Minimis Source. EPA proposes to rely on the criteria applied

under its new source permitting programs (40 CFR 51.165(b)) as a guide

in determining when a source category is de minimis for the purposes of

determining whether RACM must be applied: a de minimis source or source

category is one that contributes less than

[[Page 15932]]

5 g/3 of PM-10 to a location of expected 24-hour

exceedances and 1 g/m3 to a location of expected

annual violation. To be a considered a de minimis source for the

purposes of this RACM analysis, the source had to be de minimis for

both the 24-hour and annual standard. As discussed previously in

section IV.B., focusing on what is reasonable and practicable for

significant sources is consistent with the CAA's scheme of graduated

controls for PM.

EPA has used the results from the State's microscale plan to

identify which source categories are significant and de minimis for the

24-hour standard for the purposes of RACM analysis. As discussed in

EPA's final action on the microscale plan (62 FR 41856), the

significant source categories for the 24-hour standard are unpaved

roads, unpaved parking lots, disturbed cleared areas (i.e., vacant

lots), agricultural fields, and agricultural aprons. 62 FR 31031. De

minimis source categories for the 24-hour standard are industrial

yards, surface mining, other industrial activities, paved roads,

trackout, and paved parking lots.

To determine significant and de minimis sources for the annual

standard for this RACM analysis, EPA has relied on the results at the

Greenwood monitoring site in the State's Urban Airshed Model (UAM)

simulation, performed as part of ongoing work for Maricopa's serious

area PM-10 plan, see MAG Modeling TSD, Table 6.9. The complete list of

significant and de minimis sources for this RACM determination can be

found in Table 2 below. Where the air quality modeling provides only a

single impact number for a group of source categories (e.g., ``other

area sources'' which contains area source fuel combustion, open

burning, and emissions from charbroiling), EPA has assumed that the

impact of an individual source category is proportional to its presence

in the inventory for that group of source categories. In total, the de

minimis categories account for less than 10 percent of the total

exceedance value at the Greenwood

monitor.22-24,25

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

\22-24\This de minimis RACM criterion is invoked here solely for

the purposes of determining which source categories need RACM and

not for determining which source categories need controls for

attainment. See Section IV.B.

\25\EPA has already approved RACM for some of the de minimis

sources, e.g., major stationary sources, residential wood

combustion, non-road engines). Also, EPA notes that some de minimis

source categories already have substantial SIP-approved controls on

them (e.g., clean fuels and inspection and maintenance program for

on-road mobile sources) although EPA has not formally found these

controls to be RACM under the moderate area PM-10 RACM requirement

in section 189(a)(1)(C).

Table 2.--Significant and De Minimis Source Categories for Determining

RACM for the Annual Standard

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

Annual

impact at

the

PM-10 Source category Greenwood

Monitor

(g/

m3)

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

Significant Source Categories

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

Paved road dust........................................... 20.0

Unpaved road dust......................................... 2.9

Construction/earthmoving.................................. 5.4

Non-road engines.......................................... 1.2

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

De Minimis Source Categories

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

On-road mobile sources:

Gasoline-powered...................................... 0.3

Diesel-powered........................................ 0.9

Agricultural dust......................................... 0.2

Residential wood combustion............................... 0.4

Other area sources:

Fuel combustion....................................... 0.4

Charbroiling.......................................... 0.5

Other................................................. 0.5

Other non-road engines:

Locomotives........................................... 0.1

Airport ground support................................ 0.1

Major Point Sources....................................... 0.2

Windblown dust............................................ 0.4

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

b. Technological Feasibility. As the term is proposed to be used

here, technological feasibility means that the control measure is

currently available and being implemented elsewhere and that the

measure can achieve PM-10 emission reductions in Maricopa County prior

to the attainment deadline of December 31, 2001. EPA has long held that

it would not consider a measure ``reasonable'' if it could not be

implemented on a schedule that would advance the date for attainment in

the area. See 57 FR 13498, 13560.

For some measures (e.g., trip reduction ordinances), the State has

already implemented SIP-approved controls. For these measures, EPA has

evaluated the potential emission reduction benefit of additional

federal controls from a baseline that reflects the existing controls.

Finally, one measure on the list, restrictions on blowers for

landscaping, would in order to be effective require a complete ban on

leaf blowers. EPA does not believe that, under the CAA's graduated

level of controls for PM-10, that eliminating a source completely

constitutes a reasonable level of control.

c. Cost of Implementation. In considering the cost of implementing

a measure in an area, the General Preamble suggests that in case of

public sector sources and control measures, the cost evaluation should

consider the impact of the reasonableness of the measures on the

governmental entity that must bear the responsibility for their

implementation. 57 FR 13541. This statement in the General Preamble is

a recognition, as noted in section IV.B.,

[[Page 15933]]

that the regulatory scheme for PM-10 in subpart 4 establishes two

graduated levels of control, RACM and BACM, depending on the severity

of the air quality problem. As such, greater latitude is given

responsible entities to determine what is feasible and practicable when

selecting their initial RACM control strategy. Thus the nature and

scope of a potential control measure, including such factors as the

degree of capital expenditures required and lead-time needed for

legislative consideration, operational and/or infrastructural

development needs, etc., are appropriate determinants of what measures

may be ``reasonably available.''

In promulgating a FIP, EPA is the primary implementing entity. As

such, EPA must evaluate the reasonableness of potential RACM based on

its financial and resource capabilities (in the manner described above

for other governmental entities) to implement the measure . The Agency

notes that its duty to promulgate and implement FIPs is in addition to

rather than a replacement of its other duties under the Clean Air Act.

As such, where implementing a potental RACM FIP measure would require

the Agency to expend substantial efforts to acquire needed resources,

including financial resources, EPA could also take such factors into

consideration in determining whether the measure is practicable and,

thus, reasonable to implement.

A general discussion of the above-described types of constraints in

implementing measures for the Phoenix area can be found in the 1990 CO

FIP proposal. 55 FR 41210. While EPA may undertake the necessary steps

to acquire resources and funding, e.g., by diverting personnel and

funds or by submitting budget supplement requests to Congress, to

implement and enforce a FIP in Maricopa County or anywhere else in the

nation, the feasibility of such efforts, depending on the nature and

scope of the work needed to implement the proposed measure, may well

exceed what may fairly be considered reasonable or practicable. EPA has

also discussed generally the resource constraints associated with

federal implementation of transportation control measures in its

proposal of an ozone and CO FIP for the Los Angeles area. See 55 FR

36458, 36517 (September 5, 1990).

Examples of measures on the list that are generally not reasonably

within EPA's current resource constraints to implement are measures

which require substantial capital or operational expenditures. Examples

of measures in this category include building high occupancy vehicle

lanes, funding expansion of mass transit, and constructing substantial

traffic flow improvements.

6. Application of RACM Criteria

EPA applied these proposed RACM criteria to the 56 measures in

Table 1 that were found to be appropriate for federal implementation.

The results of this RACM screening are given in Table 3. Of the 56

measures, 46 were eliminated: 17 because they apply to de minimis

sources; 20 because a federal measure would not improve on the emission

reduction benefit from a SIP-approved measure; 5 because the measure

could not be feasibly implemented prior to the attainment date, one

because the measure required elimination of the source completely which

EPA believes is unreasonable, and 3 because of cost considerations. A

more detailed discussion of EPA's justifications for rejecting

potential RACM measures based on these RACM criteria can be found in

the TSD for this proposed rulemaking.

As seen from Table 3, ten measures remain after the application of

the RACM criteria. These measures are a variety of potential fugitive

dust controls for unpaved roads, unpaved parking lots, disturbed

cleared land, and agriculture. Therefore, as described in detail in

section V.A.7, EPA is proposing federal RACM measures to address these

fugitive dust sources including a federal fugitive dust rule and an

enforceable commitment for the agricultural sector.26

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

\26\One significant source category for the annual standard,

paved roads, is not currently being addressed comprehensively

through SIP-approved RACM or proposed FIP RACM. While EPA analyzed

40 potential measures for this source category (see categories A.1.

and A.2. on Table 1), only one of these measures was found to be a

FIP RACM. EPA notes, however, that the State has a number of SIP-

approved measures already in place, including a trip reduction

program, that reduce emissions from this category.

Table 3.--FIP RACM Evaluation\1\

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

Reasonable

Source category and measure De Minim is Technically implementation FIP RACM

Source feasible cost

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

A.1. Paved Road Dust--Reduce Dust (Silt) Loading

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

1. Pave, vegetate, or chemically stabilize access

points where unpaved traffic surfaces adjoin paved

roads (1)............................................ N Y Y Y

2. Require haul trucks to be covered (1).............. Unk\2\ N-1 .............. N

3. Provide for traffic rerouting/rapid clean-up of

temporary sources of dust (water erosion, track out,

material spills) (1)................................. Unk N-1 .............. N

5. Require curbing and pave or stabilize road

shoulders (1)........................................ Unk N-1 .............. N

6. Provide for stormwater drainage to prevent water

erosion onto paved roads (2/3)....................... N N-1 N N

7. Mitigation of freeway construction impacts (1)..... Unk N-1 .............. N

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

A.2. Paved Road Dust/Tailpipe Emissions--Reduce VMT

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

1. Implement short range transit improvements (2/3)... N Y N N

2. Implement long range transit improvements (2/3).... N N-2 N N

3. Require exclusive bus lanes on arterials and

freeways (2/3)....................................... N N-2 N N

4. Expand MAG rideshare program (2/3)................. N Y N N

5. Adopt trip reduction ordinance (1)................. N N-1 .............. N

6. Establish a voluntary no drive days (1)............ N N-1 .............. N

7. Establish an areawide public awareness program (1). N N-1 .............. N

8. Build/establish park and ride lots................. N N-1 N N

9. Provide employees financial incentives (e.g., zero

bus fares) in lieu of parking (1).................... N N-1 .............. N

[[Page 15934]]

10. Require employers to provide preferential parking

for car and van pools (1)............................ N N-1 .............. N

12. Build HOV lanes on freeways (3)................... N N-1 N N

13. Build HOV lanes on arterials (3).................. N N-2 N N

14. Build HOV ramps which bypass metering signals (3). N N-1 N N

15. Promote increased bicycle use (3)................. N N-1 N N

16. Provide or require bicycle travel (e.g., lanes)

and support facilities (e.g., lockers and racks) (3). N N-1 N N

17. Promote pedestrian travel through provisions of

pedestrian facilities (e.g. sidewalks) (3)........... N N-1 N N

18. Provide pedestrian overpasses (3)................. N N-1 N N

19. Promote the use of/require employers to provide

alternative work hours (1)........................... N N-1 .............. N

20. Promote the use of/require employers to provide

alternative work weeks (1)........................... N N-1 .............. N

21. Promote the use of telecommuting (1).............. N N-1 .............. N

22. Promote the use of teleconferencing (1/2/3)....... N N-1 .............. N

25. Require merchant to provide alternative

transportation incentives to customers (1)........... N N-2 .............. N

28. Impose fee on vehicles related to emissions (smog

fees) (1)............................................ N N-2 .............. N

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

B. On-Road Vehicle Exhaust--Tailpipe and Non-VMT Reduction Measures

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

1. Expand current I/M to all model years (1/2/3)...... Y ............ .............. N

2. Expand the current I/M program state wide (1/2/3).. Y ............ .............. N

3. Expand the current I/M program county wide......... Y ............ .............. N

5. Require clean fuels for fleet vehicles............. Y ............ .............. N

6. CA new car standards............................... Y ............ .............. N

8. Scrap higher polluting vehicles (2/3).............. Y ............ .............. N

20. Alternative fuels for buses/electric shuttle buses

(1).................................................. Y ............ .............. N

21. Emission controls on public diesel vehicles (1)... Y ............ .............. N

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

C. Dust from Unpaved Road/Parking Lot/Disturbed Vacant Lots

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

2. Require sources to submit dust control plans (1)... N Y Y Y

3. Develop traffic reduction plans on unpaved roads

(1).................................................. N Y Y Y

4. Limit use of recreational vehicles on open land (1) N Y Y Y

5. Pave or stabilize unpaved roads (1)................ N Y Y Y

6. Pave or stabilize unpaved parking areas (1)........ N Y Y Y

8. Require stabilization of wind erodible soils (1)... N Y Y Y

9. Require windbreaks, watering, paving, vegetating

for windblown dust (1)............................... N Y Y Y

10. Restrict blowers for landscaping (1).............. Unk. N-3 .............. N

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

D. Agricultural Sources

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

1. Rely on soil conservation requirements (e.g.,

conservation plans) of the Food Security Act (1)..... N Y Y Y

2. Require windbreaks for agricultural sources (1).... N Y Y Y

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

I. Locomotives

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

2. Control switching locomotives (1).................. Y ............ .............. N

3. Require electrification of rail lines (1).......... Y ............ .............. N

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

J. Airplanes/Airport Ground Equipment

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

1. Centralized airport ground power systems (1)....... Y ............ .............. N

2. Reduce emissions from airport ground access

vehicles (1)......................................... Y ............ .............. N

3. Establish tighter emissions standards for new jet

engines (1).......................................... Y ............ .............. N

4. Control emissions from aircraft and ground service

vehicles (1)......................................... Y ............ .............. N

5. Require replacement of high emitting aircraft (1).. Y ............ .............. N

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

K. Other Non-Road Engines

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

2. Establish emission standards for new heavy duty

construction equipment (1)........................... Y ............ .............. N

3. Establish emission standards for off-road

motorcycles (1)...................................... Y ............ .............. N

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

\1\Technological feasibility codes on Table 3 are:

N-1. Measure is already in place in local jurisdiction. Additional federal rule would not result in additional

emission reductions.

N-2. Measure is very unlikely to result in measurable emission reductions in the Phoenix area because technology

is not available and/or demonstrated, technology will not be available prior to the attainment date, and/or

supporting infrastructure is absent (e.g., a viable transit system is necessary in order for merchant

transportation incentives to be effective).

N-3. Measure involves elimination of the source and therefore does not represent a reasonable level of control.

\2\While paved (i.e., re-entrained) road dust is clearly a significant source of PM-10 in the Phoenix

nonattainment area, the contribution of unpaved shoulders, material from haul trucks, all track out and

accidental spills to this source category is unknown.

[[Page 15935]]

a. Commitment for Agricultural Sector. (1) Summary of Proposed

Commitment and Approach EPA's RACM analysis above indicates that RACM

controls are needed for agricultural sources of PM-10. Currently, RACM

is not being fully implemented for agricultural fields and aprons in

the Phoenix area.27-29 Therefore, federal measures are

needed to reduce PM-10 from these sources.

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

\27-29\Application of Rule 310 to agricultural sources including

fields and aprons is affected by a provision in section 102 of the

rule which incorporates A.R.S. 49-504.4. Section 102 provides that

Rule 310 ``shall not be construed so as to prevent normal farm

cultural practices.'' Therefore, applicability of the rule to such

sources depends on the nature of the dust-generating operation. As

such, Rule 310 applies to some operations on agricultural fields and

aprons and not to others.

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

EPA is proposing an enforceable commitment to adopt and implement

RACM as required by CAA section 189(a)(1)(C) for the agricultural

sector. In order to develop the RACM, as discussed below, EPA intends

to use a stakeholder approach which, it is anticipated, will result in

the development of best management practices (BMPs) that provide PM-10

emission reductions from agricultural sources in the nonattainment

area.

(2) Background. The microscale plan30 demonstrated that

wind-blown dust from agricultural fields and aprons (i.e., farm access

roads and equipment turnaround areas) significantly contributes to

exceedances of the 24-hour standard at the Gilbert and West Chandler

monitoring sites. These sites are representative of the numerous

agricultural-urban interface areas located in the nonattainment area.

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

\30\In addition to EPA's standard AP-42 emission methodologies

and some other prior special studies for particular source

categories, the microscale study included field surveys, aerial

photography, examination of activity logs, and interviews with

source operators. The study resulted in a substantially better

emissions inventory data than is usually available.

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

The Gilbert monitoring site is located on the grounds of the City

of Gilbert's wastewater treatment plant and has agricultural fields and

aprons to its north, an unpaved and paved parking lots to the north and

west, and a city park to the south. Modeling showed that windblown dust

from agricultural fields and unpaved parking lots was the largest

contributor to the exceedance at the Gilbert monitor. The West Chandler

monitoring site is bordered on the west by agricultural fields and the

right of way for the Price Road/Freeway, which was under construction

in early 1995. Modeling showed that windblown dust, mainly from

agricultural fields and road construction, was the largest contributor

to the exceedance at the West Chandler monitor.

There are approximately 600 growers farming approximately 300,000

acres of land in Maricopa County. An estimated 63 percent of the

agricultural activity in Maricopa County occurs within the

nonattainment area. Upland cotton (112,000 acres), alfalfa (54,000

acres), and durum wheat (45,000 acres) comprised over two-thirds of the

crop acreage in Maricopa County during 1996. Cash receipts for crops

grown in 1996 totaled over $440 million, ranking Maricopa County second

in the state. The area is characterized by very low rainfall (7 inches

per year) and desert conditions.

Maricopa County is undergoing rapid urbanization with agricultural

land being converted into other uses at a rate of approximately 6,000

acres per year. As this urbanization continues, the amount of PM-10

associated with agricultural lands will decrease because the amount of

land being farmed within Maricopa County is shrinking. The 1996 Farm

Bill has also affected farming practices in the Maricopa County

nonattainment area. See 16 U.S.C. 3801 et seq. After 1994, land which

had been set aside under a prior U.S. Department of Agriculture (USDA)

program was placed in production (primarily alfalfa). The switch from

unplanted set-aside to planted alfalfa resulted in a relatively small

decrease in PM-10 emissions. Despite the conversion of agricultural

lands to other uses and the small increase in agricultural land being

put back into production, agricultural sources are expected to continue

to contribute to PM-10 emissions for the foreseeable future.

(3) RACM Analysis. EPA evaluated existing agriculture measures in

the South Coast Air Basin (SCAB)31 to assess potential RACM

for agriculture for the Phoenix nonattainment area.32

However, it is important to note that because agricultural sources in

the United States vary by factors such as regional climate, soil type,

growing season, crop type, water availability, and relation to urban

centers, each PM-10 agricultural strategy is uniquely based on local

circumstances. Unlike many stationary sources, which can have many

common design features, whether located in California or New Jersey,

agricultural sources and activities vary greatly throughout the

country.

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

\31\EPA identified South Coast Air Quality Management District

(SCAQMD) Rule 403.1--Wind Entrainment of Fugitive Dust. This rule

applies to any activities which can generate fugitive dust when

winds exceed twenty-five miles per hour (mph) in the Coachella

Valley Planning PM-10 nonattainment area. Rule 403.1 requires that

any person involved in activities which both occur in the Coachella

Valley Blowsand Zone and are capable of generating fugitive dust to

stabilize deposits using water or dust suppressants, or install wind

breaks, and also restricts agricultural tilling when wind speeds

exceed twenty-five mph and requires that inactive disturbed surface

areas be stabilized using water or dust suppressants.

EPA also identified SCAQMD 403--Fugitive Dust (amended February

14, 1997), which requires any person generating fugitive dust from

an active operation, open storage pile, or disturbed surface to

implement RACM or BACM listed in the rule to minimize fugitive dust

(e.g., apply chemical stabilizers on disturbed surface areas; apply

water to unstabilized areas three times per day). Subject sources

may submit a dust control plan in lieu of the control measures

listed in the rule.

Finally, EPA identified SCAQMD Rule 1186--PM10 Emissions From

Paved and Unpaved Roads, and Livestock Operations, which is intended

to reduce PM-10 entrained in the ambient air as a result of

vehicular travel on paved and unpaved roads, and at livestock

operations. The requirements affecting livestock operations include:

cease hay grinding between 2 and 5 p.m. if visible emissions extend

50 feet from the source; and treat unpaved access connections and

unpaved feed access areas using either pavement, gravel, or asphalt.

A more detailed discussion of the provisions found in these

rules can be found in the Technical Support Document for today's

proposed action.

\32\EPA recognizes the role of USDA's Natural Resources

Conservation Service (NRCS) in working with individual growers to

voluntarily develop Soil Conservation Plans (SCPs). Because SCPs in

the Maricopa County area are voluntary (approximately one-third of

the growers have a SCP), grower-initiated, and have very minimal air

quality benefits as currently designed, the use of SCPs in Maricopa

County was determined to not meet RACM and thus not considered a

viable option for the proposed FIP. See 57 FR 13498, 13541. In

addition, representatives from NRCS and the Arizona Farm Bureau

Federation have indicated to EPA that they do not support using SCPs

for RACM.

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

With respect to Phoenix and the Los Angeles area, EPA determined

that the two areas differ in a number of key characteristics (e.g.,

crops grown, soil types, climate, and number of growers affected). In

assessing RACM for agricultural sources, EPA considered the uniqueness

of the myriad factors affecting agricultural activity in the

nonattainment area. 57 FR 13498, 13540-13541. Based on this initial

screening, EPA decided that it would not be responsible to propose the

SCAQMD rules at this time because the Agency could not reasonably

conclude that their implementation would in fact result in air quality

benefits for the nonattainment area. Instead, the SCAQMD rules will be

further assessed as part of the BMP development process. This process

will allow EPA to take advantage of various local and national

agricultural expertise to more fully evaluate whether the SCAQMD rules,

portions thereof, or other unique emission reduction strategies would

contribute to attainment and, therefore, should be applied in Maricopa

County.

[[Page 15936]]

(4) Proposed Commitment

(i) Discussions With Stakeholders. In recognition of the need to

address agriculture's contribution to the PM-10 exceedences, the

microscale plan included a March 27, 1997 letter signed by the Arizona

Department of Environmental Quality (ADEQ), MCESD and the NRCS. The

letter stated the intent of the three agencies to work cooperatively

toward strategies that address PM-10 emissions from agricultural lands

within Maricopa County. The three agencies sponsored meetings in March

and May, 1997 which brought stakeholders together to discuss

agriculture and PM-10. At the same time, and into the summer of 1997,

MAG was working with the Maricopa County Farm Bureau on possible

emission controls for agricultural lands as part of the PM-10 serious

area plan development. Also during the summer of 1997, EPA held

meetings with ADEQ, MAG, MCESD, and NRCS to discuss potential

strategies to reduce PM-10 from agricultural lands.

Because there were two separate ongoing efforts with respect to PM-

10 emissions from agricultural sources, as described above, EPA used

these meetings to keep apprised of the progress of the two efforts, as

well as to discuss implementation issues related to agricultural

control measures. The MAG discussions with the Maricopa Farm Bureau

resulted in the identification of several potential PM-10 control

measures by early fall, 1997. These measures were voted on and approved

by the Maricopa County Farm Bureau Board in September, 1997. At that

time, EPA decided that a joint discussion with ADEQ, MCSED, MAG, NRCS,

and the Farm Bureau would be beneficial to both the FIP and SIP

processes.

Thereafter, EPA contacted the NRCS, the Arizona Farm Bureau

Federation, and other stakeholders and arranged for a November 12-14,

1997 tour of agricultural activities to better understand their impact

in Maricopa County. Several meetings were held with these same

stakeholders. The meetings provided an opportunity for EPA to discuss

the upcoming FIP proposal and the need to work

collaboratively33 on strategies addressing agriculture and

PM-10. The tour and subsequent meetings allowed EPA to work directly

with the leaders in the Maricopa County agricultural and regulatory

community and set the stage for future discussions on possible

strategies for reducing PM-10 from agriculture in the area. Subsequent

meetings on December 2 and 16, 1997 among EPA, Farm Bureau

representatives, farmers, NRCS, ADEQ, MCESD, and MAG resulted in a

general consensus on using a BMP approach to develop measures to reduce

PM-10 from agriculture. On January 7, 1998, EPA Region IX sent a letter

to the Maricopa County Farm Bureau stating EPA's intention to include

the BMP approach in the proposed FIP. On January 21, 1998, the Maricopa

County Farm Bureau sent a letter to EPA Region IX indicating their

general support for the BMP approach. The letter also provided their

recommendations on milestones and timeframe needed for a successful BMP

approach.

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

\33\In early 1997, the USDA's Agricultural Air Quality Task

Force began discussions with EPA on issues related to agriculture

and air quality. Over the course of the year, the Task Force drafted

a Memorandum of Understanding (MOU) between USDA and EPA that

establishs a formal relationship for sharing expertise and involving

the agricultural community in air quality issues. The MOU was signed

by EPA on February 25, 1998 and by the USDA on 1/14/98. EPA believes

that the BMP approach follows the cooperative spirit outlined in the

MOU.

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

(ii) BMP Approach. The proposed BMP approach for addressing PM-10

from agricultural sources could be modeled after an analogous BMP

approach used for managing fertilizer applications and protecting

groundwater in Arizona. Under the nitrogen fertilizer BMP program,

legislation was passed in the late 1980s giving the Director of ADEQ

the authority to oversee the development and implementation of BMPs. An

Advisory Committee, comprised of representatives from key government

agencies, universities, and the agricultural community was established

to develop and recommend BMPs for adoption by ADEQ. After adoption of

the BMPs, supplemental guidance documents were developed by the

University of Arizona to assist growers, and an extensive grower

education campaign was undertaken to increase the likelihood for

successful BMP implementation. The BMPs eventually became part of the

Arizona Administrative Code (Title 18, Chapter 9, Article 2), which

requires that all persons engaged in the application of nitrogen

fertilizers be issued a general permit and comply with the six

agricultural BMPs stated in the law. A similar approach was also used

to develop BMPs for concentrated animal feeding operations in Arizona.

(iii) FIP Proposal. EPA is proposing an enforceable commitment to

adopt and implement RACM to reduce PM-10 emissions from agricultural

sources. The proposed FIP commitment includes a series of enforceable

milestones and due dates listed in Table 4 to assure adoption and

implementation of RACM. EPA would initially convene a stakeholder-based

process to begin formal development of draft BMPs. Stakeholder groups

represented will likely include but not be limited to the Arizona Farm

Bureau Federation, Maricopa County Farm Bureau, ADEQ, MAG, MCESD, NRCS,

Cooperative Extension, the University of Arizona, tribes, and

environmental and/or public health organizations. This effort would

build upon the stakeholder-based discussions which occurred in 1997 and

early 1998. By September 1998, the stakeholders would begin to draft

BMPs. Potential BMPs likely to be considered include but are not

limited to: windbreaks, vegetative covers, chemical or physical soil

stabilizers, improved tillage practices, tillage limitations during

high wind events, speed reductions on unpaved or untreated farm roads,

and tillage pre-irrigation. The milestones by which EPA proposes to

complete various aspects of BMP development and implementation are as

follows. By September 1999, EPA will have drafted the BMPs developed

for official public comment, which will occur through a Notice of

Proposed Rulemaking. After public comment and additional stakeholder

meetings, EPA will finalize the BMPs in a Notice of Final Rulemaking.

In June 2000, BMP implementation will begin with an extensive

collaborative public outreach and education campaign. Guidance

documents would be developed to assist growers with implementation of

the BMPs. Compliance assistance would also be a key element of the BMP

program.

Table 4.--Proposed Deadlines for EPA Adoption/Implementation of RACM for

Agriculture in Maricopa

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

Milestones Due date

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

Notice of Proposed Rulemaking for RACM....... September 1999.

Notice of Final Rulemaking for RACM.......... April 2000.

[[Page 15937]]

RACM implementation.......................... June 2000.

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

(5) FIP Replacement.

Although EPA is only required in the FIP to meet the CAA RACM

requirement, the State is expected, as required for PM-10 serious

nonattainment areas, to develop BACM for agricultural sources. The

State expects the BACM developed for the serious area plan to also

Satisfy any remaining CAA RACM requirements. EPA is committed to

working with ADEQ and the other stakeholders to develop a SIP measure

to replace the proposed enforceable commitment.

While EPA's intended BMP approach is designed to meet the RACM

requirement, the Agency believes it can serve as a potential starting

point and model for the development of a State-led SIP process for

addressing BACM for agricultural sources. Thus, the stakeholders could

potentially build upon the BMP approach initiated for the FIP to

address both RACM and BACM requirements for the agricultural sector in

the SIP. The Arizona Farm Bureau Federation, the Maricopa County Farm

Bureau, NRCS, ADEQ, and other regulatory agencies are currently working

collaboratively to develop a State-led BMP process for that purpose.

EPA strongly endorses such a process. However, because EPA has not

received to date an adequate SIP submittal addressing the

implementation of RACM by June 2000 for agricultural sources of PM-10,

EPA is proposing an enforceable commitment for those sources as

described above.

b. Rule for Unpaved Parking Lots, Unpaved Roads and Vacant Lots.

Fugitive dust from unpaved parking lots and unpaved roads is primarily

caused by vehicle traffic. When vehicles travel over unpaved surfaces,

they raise the silt content (i.e., grind up dirt so as to result in a

greater abundance of finer particles). The more vehicles (and the

faster they travel) on unpaved surfaces, the more PM-10 is stirred up

in clouds of fugitive dust.

On vacant lots, fugitive dust emissions are caused by virtually any

activity which disturbs an otherwise naturally stable parcel of land,

including earth-moving activities, weed abatement, material dumping and

vehicle traffic. Once disturbed, the vacant lot may continuously

generate dust until it is restabilized. Since wind conditions affect

the amount of dust raised on vacant lots, PM-10 emission impacts may

not be fully realized until several days following a disturbance.

MCESD's Rule 310 requires RACM for fugitive dust sources; however,

EPA has determined that the County does not enforce the rule for three

source categories within the Phoenix PM-10 nonattainment area: unpaved

parking lots, unpaved roads and vacant lots. As a result, EPA is having

to fulfill the role of primary enforcer of the RACM requirement for

these sources and has developed its own proposed rule addressing RACM

for these sources.

EPA's regional office in San Francisco, California (EPA Region 9)

will have primary responsibility for enforcement of the proposed FIP

rule. Given the difficulties that Region 9 will inevitably face in

enforcing the RACM requirement in Arizona, EPA has designed a RACM rule

that ensures EPA enforcement of the rule will be practicable.

Furthermore, EPA believes that the proposed rule will be useful to

MCESD in future SIP efforts to control dust from these sources.

In general, EPA believes that all of the RACM requirements of the

proposed FIP rule can also be required through enforcement of Rule 310.

However, the rule's lack of specificity makes it more likely that the

agency enforcing the rule will routinely be called upon to address

which RACM should be applied to which source categories. By addressing

this issue in the FIP rule itself through detailing specific RACM

requirements, EPA hopes to reduce the extent to which sources and

others may have to consult with the Agency to determine which RACM are

appropriate for a particular source or source category.

The only proposed FIP rule requirement that is not required in Rule

310 is a recordkeeping requirement for owners/operators to maintain

records of controls implemented on unpaved roads, unpaved parking lots,

and vacant lots in order for EPA to ensure compliance with the

rule.34 The proposed recordkeeping requirements in the FIP

rule are simple and straightforward. In many cases, the owner/operator

need only retain a purchase receipt or contractor work order for the

controls implemented. More information is required when chemical

stabilization is applied as a control measure, however, this

information is readily available from vendors or easily determined at

the time of application.

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

\34\Rule 310 only requires recordkeeping for permitted dust-

generating operations.

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

(1) Summary of Proposed Rule. In developing the proposed FIP rule,

EPA utilized the RACM in Rule 310 while drawing upon several additional

sources to increase specificity of the measures. A detailed discussion

of EPA determinations and references for the proposed rule can be found

in the Technical Support Document. Specific requirements of the

proposed rule are summarized below.

Unpaved parking lots: Any owners/operators of unpaved parking lots

greater than 5,000 square feet are required to pave, chemically

stabilize, or apply gravel to the lot within eight months of the rule's

effective date. For unpaved parking lots that are used no more than 35

days per year, owners/operators may choose to apply chemical

stabilizers within 20 days prior to any day in which over 100 vehicles

enter the lot.

Unpaved roads: Any owners/operators of existing public unpaved

roads with average daily trip volumes of 150 vehicles or greater are

required to pave, chemically stabilize, or apply gravel to the unpaved

road by June 10, 2000.

Vacant lots: (1) A Dust Control Plan (as described in section 503)

is required for weed abatement operations on vacant lots that disturb

0.10 acres or more of soil by blading, disking, plowing under or other

means (excluding mowing, cutting or similar processes in which soil is

not disturbed), unless such operations receive an approved permit from

Maricopa County Environmental Services Department. (2) Any owners/

operators of an urban or suburban open area vacant lot with 0.10 acres

or more of disturbed surface area which is unused or undeveloped for

more than 15 days are required to establish vegetation, apply dust

suppressants, restore to a natural state, or apply gravel to all

disturbed surfaces within eight months following the effective date of

the proposed rule or within eight months following the initial 15 day

[[Page 15938]]

period of inactivity, whichever is later. (3) Any owners/operators of

an urban or suburban open area vacant lot which has a disturbed surface

due to motor vehicles (including off-road vehicles) are required to

place signs, fencing, shrubs, trees, or cement barriers to prohibit

vehicle entry along the access perimeter.

The threshold level of 0.10 acres for weed abatement and disturbed

surface areas is the same threshold level for the permitting of

construction sites in Rule 310.35 Currently Rule 310 does

not contain a threshold exemption for vacant lots. EPA is requesting

comments on whether the 0.1 acre threshold is the appropriate threshold

for determining when controls on vacant lots is required.

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

\35\MCESD is currently preparing a revision to Rule 310 which

would require dust control plans for weed abatement operations that

disturb soil surfaces of 0.1 acres or greater.

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

All categories: As an alternative to compliance with any of the FIP

rule requirements (with the exception of the weed abatement provision),

owners/operators may use alternative control measures approved by EPA.

Proposed alternative control measures must be submitted to EPA for

approval prior to the rule's deadline for RACM implementation for the

source. Should EPA disapprove an alternative control measure, the

owner/operator must begin implementing RACM as required in the rule no

later than 60 days after receiving notice of disapproval.

Recordkeeping: Owners/operators are required to maintain records of

controls implemented on unpaved roads, unpaved parking lots, and vacant

lots.

(2) Discussion. The proposed FIP rule includes three to four RACM

options for each source category. In order to ensure that emission

reductions are achieved, the FIP rule only specifies control measures

which have a reasonably high level of certainty in their control

effectiveness and enforcement. However, EPA is willing to consider

other measures, and is therefore allowing submittal of alternative

control measures for any of the source categories subject to EPA

approval.

Surveys of fugitive dust sources and control measures are required

to be conducted by EPA or its contractor in the proposed FIP rule in

order to improve knowledge of the universe of sources and provide

feedback on the rule's effectiveness. The surveys will enable

regulators to better estimate the contribution of unpaved roads,

unpaved parking lots and vacant lots to Maricopa County's PM-10

inventory, identify control measures that are the most frequently

implemented, and study the effectiveness of these measures in

controlling fugitive dust.

Tests in order to determine compliance with the proposed FIP rule

would be conducted by EPA or its contractor, and do not pose additional

requirements on sources subject to the rule. Implementation of some

control measures, such as paving unpaved roads, are obvious upon

inspection and tests are not necessary to determine compliance. For

other control measures, such as application of chemical stabilizers and

gravel, a test is needed to determine whether the surface is

sufficiently stabilized to prevent or minimize fugitive dust emissions.

For determining whether unpaved roads and unpaved parking lots are

stabilized, EPA is proposing visible opacity test methods associated

with vehicle use (Reference Method 9, Methods 203A, 203B, and 203C),

with opacity readings conducted according to 203C. These methods

incorporate a fugitive dust element to Reference Method 9, which is

most appropriate for measuring emissions from stationary sources of PM-

10. Method 203C allows ``instantaneous'' readings averaged over a

period of one minute, taken at 5 second intervals. EPA first proposed

Reference Method 9, Methods 203 A, B, and C in 1993 (Appendix M, part

51) and has incorporated public comments into the test methods. While

EPA has not yet promulgated the methods, for purposes of federal

enforcement of the FIP rule, they can be used as credible evidence

until such time as EPA publishes a final rulemaking for the test

methods (40 CFR part 52.12).

For determining whether vacant lots have stabilized surfaces, EPA

is proposing and requesting comment on test methods concerning visible

crusts, vegetation, and threshold friction velocity of soil samples.

Information on test methods proposed for this FIP is available in the

TSD and the rulemaking docket.

The proposed FIP rule does not preclude the right of any State or

locality to adopt or enforce an emission standard or limitation which

is more stringent than this rule (Clean Air Act section 116).

(3) Compliance Approach. Upon promulgation of the FIP, EPA will

implement its rule for unpaved parking lots, unpaved roads, and vacant

lots. Thus, EPA will take on responsibilities that are normally

performed by the local air quality regulatory agency, in this case,

MCESD. These responsibilities would include such activities as:

refining EPA's information on the universe of sources subject to the

rule, developing an outreach/compliance assistance program for the

affected community, inspecting sources subject to the rule, and

following up with an appropriate enforcement response in the event of

rule violations.

Although the cities in the Phoenix area have provided information

on the sources within their jurisdictions, EPA will be using

contractual assistance to obtain additional information on the sources

subject to the FIP rule. This information will be used by EPA to

perform the surveys described above, to evaluate the rule's

effectiveness, and to identify sources for potential inspections. This

information can also be used (and EPA will encourage its use) by

Maricopa County to better implement Rule 310.

EPA will be implementing the FIP rule by providing resources

directly from the Regional Office in San Francisco. Working with the

information provided by the contractor, Region 9 will develop a

compliance assistance strategy that will ensure that sources subject to

the FIP rule are informed about the rule, and understand how the rule

applies to them, what their compliance options are, and the need to

comply with the provisions in the rule. Once EPA compliance assistance

efforts are underway, EPA will inspect these sources for compliance

with the FIP rule.

In addition, EPA exercises a traditional oversight role over state

and local air quality programs by making periodic visits to the states

within Region 9 and conducting joint inspections with the state and/or

local regulatory agencies. These joint inspections can cover a variety

of sources, and, in the future, will include sources covered by the FIP

rule.

Also, because MCESD does not have sufficient resources to enforce

Rule 310 for unpaved roads, unpaved parking lots, and vacant lots, EPA

intends to provide two additional inspection resources to MCESD by

supplementing the MCESD CAA section 105 grant in October 1998. These

additional inspectors will perform inspections for EPA with respect to

the three source categories subject to the FIP Rule. These additional

resources will be provided to MCESD as long as the FIP is in place.

(4) Replacement of FIP Rule. MCESD is currently trying to obtain

additional resources to expand implementation of Rule 310. If MCESD

obtains the additional resources and is able to develop an enforcement

strategy for the vacant lot, unpaved parking lot and unpaved road

sources covered by the FIP rule, this strategy may be submitted to EPA

for approval as meeting the

[[Page 15939]]

CAA's RACM requirement for these sources. As part of any implementation

strategy that MCESD submits for EPA approval, the County will need to

provide evidence that it has adequate resources of its own to ensure

that Rule 310 is fully enforced for all fugitive dust sources. If

approved, such a strategy will allow EPA to rescind its FIP rule.

B. Impracticability Demonstration.

The Clean Air Act requires moderate PM-10 nonattainment areas to

demonstrate attainment of the PM-10 annual and 24-hour standards, or to

show that attainment by December 31, 2001 is impracticable (see section

IV.B. of this notice). For this proposed FIP, EPA is making the latter

demonstration. Based on modeling work performed by the State, existing

State controls together with the RACM being proposed by EPA are not

sufficient for attainment of either the 24-hour or the annual PM-10

standard by December 31, 2001.

1. Annual Standard

For the annual standard attainment analysis, EPA relied on the

State's simulation of the 1995 year found in the MAG Modeling TSD which

was performed as part of ongoing work for Maricopa's PM-10 serious area

plan. This work used a variant of the Urban Airshed Model (UAM), which

is the EPA-recommended model for attainment demonstrations for ozone

and carbon monoxide, though it can be used to model any pollutant. The

UAM results were scaled using factors derived from observed PM-10

concentrations and from emissions projected to 2001. Because the

Greenwood monitoring site had the highest simulated annual

concentrations, EPA has used this site as the basis for the annual

standard impracticability demonstration.

As can be seen in Table 5, even assuming 100 percent control for

sources subject to the proposed FIP rule (an unrealistic level of

control, actual control levels will be less36), simulated

concentrations are still over the annual standard of 50 g/

m\3\. Thus, EPA proposes to find that attainment of the annual PM-10

standard is impracticable with the implementation of RACM.

Table 5.--Annual Standard Impracticability Demonstration

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

Concentration Concentration

after SIP Maximum after FIP

Source category controls possible controls

g/ control g/

m\3\ (percent) m\3\

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

Paved road dust...................................................... 20.0 ........... 20.0

Unpaved road dust.................................................... 2.9 100 0.0

Gasoline and Diesel vehicle exhaust.................................. 1.2 ........... 1.2

Agricultural dust.................................................... 0.2 100 0.0

Other area sources................................................... 1.4 ........... 1.4

Residential wood combustion.......................................... 0.4 ........... 0.4

Construction/earth moving............................................ 5.4 ........... 5.4

Construction equipment, locomotives, other non-road engines.......... 1.4 ........... 1.4

Major point sources.................................................. 0.2 ........... 0.2

Windblown dust....................................................... 0.4 100 0.0

Anthropogenic Total.................................................. 33.5 ........... 30.0

Background........................................................... 22 ........... 22

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

Total.......................................................... 55.5 ........... 52.0

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

2. 24-hour Standard

For its 24-hour standard attainment analysis, EPA relied on the

modeling in Arizona's microscale plan. This modeling used the ISCST

(Industrial Source Complex, Short Term) model, an EPA guideline model

often used for stationary source permit applications, and well-suited

to the locally-driven exceedances that were the focus of the microscale

plan. ISCST was used to simulate PM-10 concentrations at representative

sites subject to emissions from various source types and at which 24-

hour exceedances had been observed. These monitoring sites were: 1)

Salt River, in an industrial area; 2) Gilbert, affected by agricultural

and unpaved parking lot fugitive dust emissions; 3) Maryvale, with

disturbed cleared areas nearby due to construction of a park; and 4)

West Chandler, near a highway construction project. These sites were

selected to represent a variety of conditions within the Maricopa

nonattainment area.

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

\36\Estimated regional emission reductions from the proposed FIP

rule are discussed in Section V.C.1.

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

The microscale plan demonstrated attainment at the Salt River and

Maryvale sites, and EPA approved the attainment demonstrations at these

sites at the time it took final action on the microscale plan. 62 FR

41856. The microscale plan did not demonstrate attainment at the West

Chandler and Gilbert sites. These sites will be addressed here.

The proposed FIP rule requires RACM for unpaved roads, vacant lots,

and unpaved parking lots. These sources in total contribute 25 percent

of the emissions to the exceedance at the Gilbert site and just 1

percent of the emissions to the exceedance at the West Chandler site.

(For both sites, fugitive dust from agricultural sources is the largest

contributor to the exceedances.) The proposed FIP rule has a

substantial impact for the Gilbert site, reducing ambient

concentrations from 213 to 176 g/m\3\ but much less effect at

West Chandler, reducing concentrations from 332 to just 316 g/

m\3\. See Table 6. Because the proposed RACM do not result in

attainment at either site, EPA is proposing to find that attainment of

the 24-hour standard is impracticable with the implementation of RACM.

As can be seen from Table 6, attainment at both sites will require

substantial reductions from agricultural sources in addition to

reductions from unpaved roads, unpaved parking lots, and vacant lots.

While reductions from agricultural sources are expected through the

implementation of BMPs by 2001, EPA is unable to quantify the impact of

these BMPs at this time because they have not been defined sufficiently

to determine the expected level of control. Once the BMPs have been

defined, EPA will better be able to estimate reductions from

agricultural sources and will revisit any final impracticability

demonstration for the 24-hour standard and modify the demonstrations as

necessary.

[[Page 15940]]

Table 6.--Impracticability Demonstration for the 24-hour PM-10 Standard

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

Concentration after SIP Concentration after FIP

controls g/m3 FIP control controls g/m3

Source category ---------------------------- (percent) ---------------------------

Chandler Gilbert Chandler Gilbert

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

Agricultural fields........................ 194.7 ---- ---- 194.7 ----

Agricultural aprons........................ 21.7 55.6 ---- 21.7 55.6

Road construction.......................... 6.9 ---- ---- 6.9 ----

Unpaved roads.............................. 0.5 0.5 64 0.2 0.2

Paved Roads................................ 0.2 1.6 ---- 0.2 1.6

Unpaved parking lots....................... ............ 51.3 56 ............ 22.6

Vacant lots................................ 28.1 14.5 56 12.4 6.4

Anthropogenic Total........................ 252.1 123.4 ........... 236.1 86.3

Background................................. 80 90 ........... 80 90

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

Total.................................. 332.1 213.4 ........... 316.1 176.3

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

See section V.C. immediately below for a discussion of the

estimated emission reductions from the FIP control measures.

C. Reasonable Further Progress (RFP) Demonstration

As discussed previously in Section IV.C. of this preamble, EPA

interprets the RFP requirement for areas demonstrating impracticability

as being met by a showing that all RACM will be implemented and that

the implementation of all RACM has resulted in incremental emission

reductions below pre-implementation levels. For the purposes of this

proposed RFP demonstration, pre-implementation levels are 1998 emission

levels, the promulgation year for this FIP. Because CAA section 171(1)

defines RFP reductions as being ``for the purpose of ensuring

attainment* * *by the applicable attainment date,'' post-implementation

levels are 2001 emission levels, the statutory attainment

year.37

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

\37\The 1998 emission levels also include the implementation of

improved controls on construction sources that were approved as BACM

in the microscale plan and were to be implemented by mid-1997. No

increase in control effectiveness after 1998 is expected from these

State BACM measures or from other approved State RACM measures;

therefore, the RFP demonstration proposed here only addresses the

incremental reductions resulting from the proposed FIP measures.

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

RFP is demonstrated separately for the annual and 24-hour standards

because the mix of sources contributing to the annual standard

exceedances differs from that contributing to the 24-hour exceedances.

In addition, since PM-10 exceedances are related almost entirely to

primarily-emitted PM-10, only emissions of primarily-emitted PM-10 are

evaluated for RFP.

1. Annual Standard

The proposed RFP demonstration for the annual standard is

summarized here and in Table 7. A complete discussion of the RFP

demonstration can be found in the TSD for this proposed action.

Emission levels for 1998 and 2001 were calculated by growing

emissions from the emission inventory base year of 1994 and the

modeling year of 1995 based on growth factors contained in the MAG

Modeling TSD and by incorporating reductions from approved State RACM

and BACM controls. Emissions levels for 2001 also reflect the estimated

emission reductions from the proposed FIP rule for unpaved roads. The

estimated effectiveness of controls on unpaved roads, 80 percent, was

based on the research done for the microscale plan on the effectiveness

of controls for unpaved parking (see Table 4-1 in the final Microscale

Plan) and assumes a rule effectiveness of 80 percent per EPA's guidance

and that 90 percent of the VMT on unpaved roads will be impacted by the

FIP rule

This text is long and has been trimmed here. Open the source document for the complete record.

This is a copy of a public record, reproduced as it was published. It is not legal advice, and it may not be the version a court would rely on. Check the official source before you cite it.

A word about cookies

We need a few to keep you signed in and the library working. The rest help us see which pages people use and where they get stuck. They stay off unless you say yes.

Promulgation of Federal Implementation Plan for ArizonaPhoenix Moderate Area PM-10; Disapproval of State Implementation Plan for ArizonaPhoenix Moderate Area PM-10 · 63 FR 15920 | Frix