60328 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

of $10,125. Such fee is not required 

when, in connection with the change 

sought under this paragraph, a petition 

is filed for the establishment of new 

tolerances to take the place of those 

sought to be revoked and a fee is paid 

as required by paragraph (a) of this 

section.

* * * * *

(l) * * * A fee of $2,025 shall 

accompany every request for a waiver or 

refund, as specified in paragraph (m) of 

this section, except that the fee under 

this paragraph shall not be imposed on 

any person who has no financial interest 

in any action requested by such person 

under paragraphs (a) through (j) of this 

section.***

* * * * *

33. Section 180.40 is amended by 

revising the last sentence in paragraph 

(f) to read as follows:

§ 180.40 Tolerances for crop groups.

* * * * *

(f) * * * Processing data will be 

required prior to establishment of a 

group tolerance, and tolerances will not 

be granted on a group basis as to 

processed foods prepared from crops 

covered by the group tolerance.

* * * * *

34. Section 180.1229 is added to 

subpart D to read as follows:

§ 180.1229 Benzaldehyde; exemption from 

the requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of benzaldehyde when used as a bee 

repellant in the harvesting of honey. 

35. Section 180.1230 is added to 

subpart D to read as follows:

§ 180.1230 Ferrous sulfate; exemption 

from the requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of ferrous sulfate. 

36. Section 180.1231 is added to 

subpart D to read as follows:

§ 180.1231 Lime; exemption from the 

requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of lime. 

37. Section 180.1232 is added to 

subpart D to read as follows:

§ 180.1232 Lime-sulfur; exemption from 

the requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of lime-sulfur. 

38. Section 180.1233 is added to 

subpart D to read as follows:

§ 180.1233 Potassium sorbate; exemption 

from the requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of potassium sorbate. 

39. Section 180.1234 is added to 

subpart D to read as follows:

§ 180.1234 Sodium carbonate; exemption 

from the requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of sodium carbonate. 

40. Section 180.1235 is added to 

subpart D to read as follows:

§ 180.1235 Sodium hypochlorite; 

exemption from the requirement of a 

tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of sodium hypochlorite. 

41. Section 180.1236 is added to 

subpart D to read as follows:

§ 180.1236 Sulfur; exemption from the 

requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of sulfur. 

42. Section 180.1237 is added to 

subpart D to read as follows:

§ 180.1237 Sodium metasilicate; 

exemption from the requirement of a 

tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of sodium metasilicate when used as 

plant desiccants, so long as the 

metasilicate does not exceed 4% by 

weight in aqueous solution. 

43. Section 180.1238 is added to 

subpart D to read as follows:

§ 180.1238 Oil of lemon; exemption from 

the requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of oil of lemon when used as a 

postharvest fungicide. 

44. Section 180.1239 is added to 

subpart D to read as follows:

§ 180.1239 Oil of orange; exemption from 

the requirement of a tolerance. 

An exemption from the requirement 

of a tolerance is established for residues 

of oil of orange when used as a 

postharvest fungicide.

[FR Doc. 04–22584 Filed 10–7–04; 8:45 am] 

BILLING CODE 6560–50–S

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Parts 52 and 81 

[AZ104–0069; FRL–7823–6] 

Approval and Promulgation of 

Implementation Plans and Designation 

of Areas for Air Quality Planning 

Purposes; Arizona

AGENCY: Environmental Protection 

Agency (EPA).

ACTION: Proposed rule.

SUMMARY: EPA is proposing to approve 

the Maricopa Association of 

Governments (MAG) serious area carbon 

monoxide (CO) state implementation 

plan (SIP) for the Maricopa County CO 

nonattainment area (the metropolitan 

Phoenix area, Arizona) as meeting the 

Clean Air Act (CAA) requirements for 

serious CO nonattainment areas. We are 

also proposing to approve the MAG CO 

redesignation request and maintenance 

plan for the Maricopa County CO 

nonattainment area as meeting CAA 

requirements for redesignation requests 

and maintenance plans. In addition, we 

are proposing to make a boundary 

change under Section 107 of the CAA to 

take the Gila River Indian Community 

(GRIC) out of the Maricopa County 

maintenance area. The portion of the 

Gila River Indian Community which is 

currently in the Maricopa County CO 

nonattainment area will be 

‘‘unclassifiable/attainment’’ for CO, and 

will not be subject to the MAG CO 

Redesignation Request and Maintenance 

Plan.

DATES: Written comments must be 

received at the address below on or 

before November 8, 2004.

ADDRESSES: Formal written comments 

should be mailed or emailed to Wienke 

Tax, Office of Air Planning (AIR–2), 

U.S. Environmental Protection Agency, 

Region 9, 75 Hawthorne Street, San 

Francisco, CA 94105–3901, 

tax.wienke@epa.gov. Comments may 

also be submitted through the Federal 

Register Web site at http://

www.regulations.gov. We prefer 

electronic comments. 

You can inspect copies of EPA’s 

Federal Register document and 

technical support documents (TSD) at 

our Region 9 office during normal 

business hours (see address above). Due 

to increased security, we suggest that 

you call at least 24 hours prior to 

visiting the Regional Office so that we 

can make arrangements to have 

someone meet you. The Federal 

Register document and TSD are also 

available as electronic files on EPA’s

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60329

Region 9 Web Page at http://

www.epa.gov/region09/air.

You may inspect and copy the 

rulemaking docket for this notice at the 

following location during business 

hours.

Environmental Protection Agency, Region 

9, Air Division, Air Planning Office (AIR–2), 

75 Hawthorne Street, San Francisco, CA 

94105.

Copies of the SIP materials are also 

available for inspection at the address 

listed below: 

Arizona Department of Environmental 

Quality, 1110 W. Washington Street, 

First Floor, Phoenix, AZ 85007, Phone: 

(602) 771–4335.

FOR FURTHER INFORMATION CONTACT:

Wienke Tax, Office of Air Planning, U.S. 

Environmental Protection Agency, 

Region 9, (520) 622–1622, e-mail: 

tax.wienke@epa.gov, or http://

www.epa.gov/region09/air.

SUPPLEMENTARY INFORMATION:

Throughout this document, the terms 

‘‘we,’’ ‘‘us,’’ and ‘‘our’’ mean U.S. EPA.

Table of Contents 

I. Summary of Today’s Proposed Action 

II. The Serious Area CO SIP for the Phoenix 

Area 

III. The CAA’s Requirements for Serious CO 

Nonattainment Area Plans 

IV. The Revised 1999 CO Plan’s Compliance 

With the CAA’s Requirements for 

Serious CO Nonattainment Area Plans 

A. Completeness of the SIP Submittals and 

Adequacy of the Motor Vehicle 

Emissions Budget 

B. Emissions Inventory 

C. Adequate Monitoring Network 

D. Implementation of Reasonably Available 

Control Measures 

E. Demonstration of Attainment 

F. Reasonable Further Progress 

G. VMT Tracking and Reporting 

H. Transportation Control Measures To 

Offset Growth in Emissions 

I. Contingency Measures 

J. Enhanced I/M Program 

K. Wintertime Oxygenated Gasoline 

Program 

L. General SIP Requirements 

V. The CAA’s Requirements for Serious CO 

Maintenance Plans and Redesignation 

Requests 

VI. The MAG CO Redesignation Request and 

Maintenance Plan’s Compliance With 

the CAA’s Requirements for CO 

Redesignation Requests and 

Maintenance Plans 

A. General SIP Requirements 

B. Attainment of the CO NAAQS 

C. Meeting Applicable Requirements of 

Section 110 and Part D 

D. Fully-Approved SIP Under Section 

110(k) of the CAA (NSR) 

E. Improvement in Air Quality Due to 

Permanent and Enforceable Measures 

F. Fully-Approved Maintenance Plan 

Under Section 175A 

VII. EPA’s Evaluation of the Transportation 

Conformity Requirements in the MAG 

CO Redesignation Request and 

Maintenance Plan 

VIII. GRIC Boundary Change Under CAA 

Section 107 

A. Background 

B. EPA Review of the Community’s 

Request 

C. Redesignation of the Northern Portion of 

the Reservation 

IX. Proposed Action 

X. Statutory and Executive Order Reviews

I. Summary of Today’s Proposed Action

We are proposing to approve the MAG 

serious area SIP for attainment of the CO 

air quality standard in the metropolitan 

Phoenix (Maricopa County), Arizona 

area. This action is based on our 

determination that this SIP complies 

with the CAA’s requirements for 

attaining the CO standard in serious CO 

nonattainment areas such as the 

metropolitan Phoenix area. 

We are also proposing to approve the 

MAG CO redesignation request and 

maintenance plan for the Maricopa 

County CO nonattainment area as 

meeting CAA requirements for 

redesignation requests and maintenance 

plans. 

We are also proposing to make a 

boundary correction under Section 107 

of the CAA for the Gila River Indian 

Community. 

II. The Serious Area CO SIP for the 

Phoenix Area 

We are proposing to approve the 

Revised MAG 1999 Serious Area Carbon 

Monoxide Plan for the Maricopa County 

Nonattainment Area, March 2001. The 

plan was developed by MAG, the lead 

air quality planning agency in Maricopa 

County. The Arizona Department of 

Environmental Quality (ADEQ) 

submitted this plan as a revision to the 

Arizona SIP on March 30, 2001 and EPA 

received it on April 2, 2001. We refer to 

this plan in this document as the 

Revised CO Plan or the Revised 1999 

CO plan, or variations of these. 

As submitted, the Revised 1999 CO 

plan consists of the main plan 

document, three volumes of technical 

appendices and three volumes of 

commitments from various agencies to 

implement CO controls. The plan 

contains 1993 and 1996 emission 

inventories, a reasonably available 

control measures (RACM) analysis, 

vehicle miles traveled (VMT) tracking 

procedures, annual VMT projections 

through 2000, and contingency 

measures. It uses the Urban Airshed 

Model (UAM) and CAL3QHC 

microscale model to model air quality in 

1994 as a base year and in 2000 as the 

attainment year and demonstrates both 

reasonable further progress towards and 

attainment of the CO standard by 

December 31, 2000. 

The MAG plan shows that the 

principal sources contributing to CO 

exceedances are gasoline on-road motor 

vehicles, gasoline non-road engines, and 

woodburning. MAG plan, p. ES–1. 

In earlier actions, we have already 

approved revisions to Arizona’s Cleaner 

Burning Gasoline (CBG) program and to 

Arizona’s Vehicle Emissions Inspection 

(VEI) Program as well as the Maricopa 

County Woodburning curtailment 

program. 69 FR 10161 (March 4, 2004), 

68 FR 2912 (January 22, 2003), 64 FR 

60678 (November 8, 1999) and 67 FR 

48718 (July 25, 2002). The revisions to 

these programs are the principal 

controls relied on in the revised MAG 

CO plan to demonstrate attainment. We 

have also previously approved the 

commitments by the Phoenix area cities 

and towns to adopt and/or implement 

CO control measures. We approved 

these commitments as part of the 

serious area PM–10 plan approval on 

July 25, 2002 at 67 FR 48718. See 40 

CFR 52.120(c)(100). Many of these 

commitments by Phoenix area cites and 

towns commit to measures which 

address CO as well as PM–10 emissions 

reductions. 

For a complete history of the CO 

planning efforts in the Phoenix area as 

well as the history of the development 

of the CO plan, please see Section 1 in 

EPA’s TSD. 

III. The CAA’s Requirements for 

Serious CO Nonattainment Area Plans 

The Phoenix area was reclassified 

from moderate to serious for CO on July 

29, 1996 (61 FR 39343) because the area 

had not attained the CO standard by the 

moderate area deadline of December 31, 

1995. As a result of this reclassification, 

Arizona was required to submit by 

February 28, 1998, a revision to its SIP 

for the Phoenix area that met the CAA 

requirements for serious CO 

nonattainment areas found in section 

187(a) and section 172(c)(1). This SIP 

revision needed to show attainment of 

the CO standard by December 31, 2000. 

In summary, these requirements are: 

(a) Implementation of all reasonably 

available control measures (RACM), 

including reasonably available control 

technology (RACT) for stationary 

sources (CAA section 172(c)(1)); 

(b) Provisions for attainment, and a 

demonstration that the plan will 

provide for attainment by no later than 

December 31, 2000 (CAA section 

187(b)(7));

(c) Provisions for such specific annual 

emission reductions as are necessary to 

attain by December 31, 2000 (CAA 

sections 172(c)(2) and 187(b)(7));

60330 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

1Serious area SIPs must also include new source 

review (NSR) permitting rules that meet the 

requirements of sections 172(c)(5) and 173. In 

practice, NSR rules are submitted and reviewed 

separately from the rest of the serious area CO plan. 

Maricopa County has submitted a complete NSR 

rule.

2 ‘‘State Implementation Plans; General Preamble 

for the Implementation of Title I of the Clean Air 

Act Amendments of 1990,’’ 57 FR 13498 (April 16, 

1992) and 57 FR 18070 (April 28, 1992).

3See ‘‘Technical Support Document for the 

Notice of Proposed Rulemaking on the Carbon 

Monoxide Serious Area Planning Requirements for 

the Maricopa County, Arizona Nonattainment 

Area,’’ June 2004, Air Division, USEPA Region 9.

(d) Forecasts of vehicle miles traveled 

(VMT) in the nonattainment area for 

each year before the year in which the 

plan projects attainment (CAA section 

187(a)(2)(A)); 

(e) An enhanced vehicle inspection 

and maintenance program (CAA section 

187(a)(6)); 

(f) An oxygenated gasoline program 

(CAA sections 187(b)(3) and 211(m)); 

(g) Transportation control strategies 

and measures to offset any growth in 

emissions from vehicle miles traveled or 

numbers of vehicle trips (CAA section 

187(b)(2)); 

(h) Contingency measures that will be 

implemented if the area fails to attain by 

its applicable deadline, fails to make 

reasonable further progress, or vehicle 

mile traveled estimates exceed those 

forecasted (CAA sections 172(c)(9) and 

187(a)(3)); 

(i) A comprehensive, accurate, current 

inventory of actual emissions from all 

sources of CO (CAA sections 172(c)(3) 

and 187(a)(5)); and 

(j) A transportation conformity budget 

(CAA section 176(c)). 

Serious area CO SIPs must also meet 

the general requirements applicable to 

all SIPs including reasonable notice and 

public hearing under section 110(a), 

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 51.111.1

We have issued a General Preamble 2

describing our preliminary views on 

how the Agency intends to review SIPs 

submitted to meet the Clean Air Act’s 

requirements for CO SIPs. We have also 

issued other guidance documents 

related to CO SIPs or provisions of those 

SIPs, including the ‘‘Technical Support 

Document to Aid States with the 

Development of Carbon Monoxide State 

Implementation Plans,’’ Office of Air 

Quality Planning and Standards 

(OAQPS), U.S. EPA, EPA–452/R–92–

003 (July 1992).

On July 8, 1999, ADEQ submitted the 

MAG 1999 Serious Area CO Plan (‘‘1999 

CO Plan’’) to EPA. We found the 

submittal complete on September 9, 

1999. The 1999 CO Plan was revised 

because the Arizona legislature passed 

House Bill (HB) 2104 during the 2000 

regular session, which repealed the 

remote sensing portion of the VEI 

program. We indicated that the 1999 CO 

Plan would need to be revised to reflect 

the change in the VEI program. MAG 

conducted new air quality modeling and 

revised the 1999 CO Plan. On April 2, 

2001, ADEQ submitted the Revised 1999 

MAG Serious Area CO Plan (‘‘Revised 

1999 CO Plan’’) to EPA. 

IV. The Revised 1999 CO Plan’s 

Compliance With the CAA’s 

Requirements for Serious CO 

Nonattainment Area Plans 

The following sections present a 

summary of our evaluation of the 

Revised 1999 CO Plan’s compliance 

with the applicable CAA requirements 

for serious area SIPs for CO. Our 

complete evaluation is found in the EPA 

TSD for this action.3 A copy of the EPA 

TSD can be obtained by calling or 

writing the contact person listed above.

A. Completeness of the SIP Submittals 

and Adequacy of the Motor Vehicle 

Emissions Budget 

The first step we take after receiving 

a SIP submittal is to determine if it is 

complete. CAA section 110(k)(1)(B) 

requires that we review all SIPs and SIP 

revisions for completeness within 60 

days of receipt. The completeness 

review allows us to quickly determine if 

the submittal includes all the necessary 

items and information we need to take 

action on it. We make completeness 

determinations using criteria we have 

established in 40 CFR part 51, Appendix 

V. 

We found ADEQ’s March 30, 2001 

submittal (received on April 2, 2001) of 

the Revised 1999 CO Plan complete and 

notified the State on October 9, 2001. 

See Letter, Jack P. Broadbent, EPA, to 

Jacqueline Schafer, ADEQ. Our 

completeness determination is 

documented in Section 2 of the EPA 

TSD. 

Section 176(c) of the Clean Air Act 

requires that federally funded or 

approved transportation plans, 

programs, and projects in nonattainment 

areas ‘‘conform’’ to the area’s air quality 

SIPs. Conformity ensures that federal 

transportation actions do not worsen an 

area’s air quality or interfere with its 

meeting the air quality standards. We 

have issued a conformity rule that 

establishes the criteria and procedures 

for determining whether or not 

transportation plans, programs, and 

projects conform. See 40 CFR part 93, 

subpart A. 

One of the primary tests for 

conformity is to show that 

transportation plans and improvement 

programs will not cause motor vehicle 

emissions to increase above levels 

needed to make progress toward and to 

meet the air quality standards. The 

motor vehicle emissions levels needed 

to make progress toward and to meet the 

air quality standards are set forth in the 

area’s air quality SIPs as an ‘‘emissions 

budget for motor vehicles.’’ The 

conformity rule’s requirements and 

EPA’s policy on emissions budgets are 

found in the preamble to the November 

24, 1993 transportation conformity rule 

(58 FR 62193–96), in the sections of the 

rule referenced above, and in 

subsequent revisions to the conformity 

rule (69 FR 40004, July 1, 2004).

Before an emissions budget in a 

submitted SIP revision may be used in 

a conformity determination, we must 

first determine that it is adequate. The 

criteria by which we determine 

adequacy of submitted emission budgets 

are outlined in conformity rules in 40 

CFR 93.118(e)(4). 

The Revised 1999 CO Plan, submitted 

on March 30, 2001, established a revised 

mobile source emissions budget of 412.2 

metric tons per day (mtpd). Revised 

1999 CO Plan, p. 9–11. We found this 

budget adequate for transportation 

conformity purposes on September 28, 

2001. See letter, Jack Broadbent, EPA 

Region 9 to Jacqueline Schafer, ADEQ, 

and James Bourey, MAG. Our finding 

was published in the Federal Register

on October 17, 2001 (66 FR 52761) and 

became effective 15 days later on 

November 1, 2001. 

B. Emissions Inventory 

CAA section 172(c)(3) requires all 

serious area CO SIP submittals to 

include a comprehensive, accurate, and 

current inventory of actual emissions 

from all sources in the base year 

inventory to forecast and backcast other 

years. Maricopa County chose the year 

1993 as the base year for its serious area 

CO SIP since it was the most complete 

emission inventory available at the time 

MAG started its modeling for the 1999 

CO Plan. MAG developed a 1994 

modeling inventory based on the 1993 

annual CO inventory. The base year and 

forecasted 1996 emission inventories 

described all the sources of CO for the 

nonattainment area. In 1998, Maricopa 

County completed the draft 1996 CO 

emissions inventory. In response to 

public comments on the Draft MAG 

1998 CO Plan, a comparison of the 1993 

and 1996 periodic inventories and an 

evaluation of the 1994 base case

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60331

modeling inventory were conducted. 

MAG subsequently revised the nonroad 

equipment modeling assumptions to be 

more consistent with the 1996 CO 

inventory. The comparison concluded 

that the 1994 modeling inventory 

contained the most recent and valid 

assumptions. 

The emission inventory is divided 

into source categories and subcategories. 

The main source categories are 

stationary sources (both point and 

aggregated), area sources, on-road 

mobile sources, and off-road mobile 

sources. Source categories provide a 

convenient way to organize the 

emission inventory and to determine the 

significance of particular sources. 

Seasonal inventories are provided to 

account for the differences in emissions 

occurring during the times of year when 

Maricopa County used to exceed the 8-

hour CO standard. We are approving the 

emission inventories of the Maricopa 

County CO nonattainment area as 

meeting the requirements of section 

172(c)(3) of the CAA. 

On September 18, 1996, we proposed 

approval of the 1990 base year CO 

emissions inventory for Maricopa 

County (see 61 FR 49087). When we 

finalize today’s proposed action, we will 

also finalize approval of the 1990 base 

year emissions inventory proposed on 

September 18, 1996. 

C. Adequate Monitoring Network 

The CAA requires states to establish 

and operate air monitoring networks to 

compile data on ambient air quality for 

all criteria pollutants. Section 

110(a)(2)(B)(i). Our regulations in 40 

CFR part 58 establish specific regulatory 

requirements for operating air quality 

surveillance networks to measure 

ambient concentrations of CO, including 

measurement method requirements, 

network design, quality assurance 

procedures, and in the case of large 

urban areas, the minimum number of 

monitoring sites designated as National 

Air Monitoring Stations (NAMS). 

Ambient networks, however, do not 

need to meet all our regulations to be 

found adequate to support air quality 

modeling. A good spatial distribution of 

sites, correct siting, and quality-assured 

and quality-controlled data are the most 

important factors for air quality 

modeling. Nonattainment area plans 

developed under title I, part D of the 

Clean Air Act are not generally required 

to address how the area’s air quality 

network meets our monitoring 

regulations. These plans are submitted 

too infrequently to serve as the vehicle 

for assuring that monitoring networks 

remain current.

For this action, we are discussing the 

adequacy of the Phoenix area 

monitoring network solely to support 

our finding that the Revised 1999 CO 

Plan appropriately evaluates the CO 

problem in the Phoenix area. Reliable 

ambient data is necessary to validate the 

base year air quality modeling which in 

turn is necessary to assure a sound 

attainment demonstration. 

There are fourteen CO monitoring 

sites in the metropolitan Phoenix area; 

thirteen are operated by the Maricopa 

County Environmental Services 

Department and one by ADEQ. Figure 

4–3 on page 4–7 in the Revised 1999 CO 

Plan lists the names of the sites and 

their locations in the Phoenix area. 

These sites all use EPA reference 

methods, are sited according to our 

regulations, meet the applicable 

monitoring objections in our 

regulations, and are operated according 

to our regulations. We therefore find 

that the monitoring network operated by 

the MCESD and ADEQ is adequate to 

support the technical evaluation of CO 

nonattainment problem in the Revised 

1999 CO Plan. See also EPA TSD section 

‘‘Ambient Air Quality Surveillance’’. 

D. Implementation of Reasonably 

Available Control Measures 

CAA section 172(c)(1) requires that 

nonattainment plans provide for the 

implementation of all reasonably 

available control measures (RACM) as 

expeditiously as practicable. We 

interpret this requirement to require a 

state to consider available measures for 

controlling CO and to adopt and 

implement those measures that are 

reasonably available for implementation 

in the area as components of the area’s 

attainment demonstration. In general, 

we do not consider a measure to be 

reasonably available if it is 

economically or technologically 

infeasible for the area, would not 

advance attainment of the relevant 

standard in the area, or is absurd, 

unenforceable or impracticable. General 

Preamble at 13560. 

As described above, the principal 

sources of CO in the metropolitan 

Phoenix area are (in order of 

importance) on-road motor vehicles, 

non-road engines, and residential 

woodburning, which collectively 

account for 99 percent of the 1996 

seasonal inventory. Revised 1999 CO 

Plan, Figure ES–2. The Revised 1999 CO 

Plan evaluates a broad range of controls 

for each of these sources categories. See

Revised 1999 CO Plan, Chapter 6. 

For on-road motor vehicles, adopted 

controls include the State’s enhanced 

vehicle emission inspection program, 

cleaner burning gasoline program 

including a 3.5 percent oxygen content 

and 9 psi volatility standard, 

requirements and incentives for the use 

of alternative fueled vehicles, and 

numerous transportation control 

measures (TCMs). See Revised 1999 CO 

Plan, Chapter 8. We find that these 

measures along with the federal motor 

vehicle tailpipe standards provide a 

comprehensive control strategy for 

attaining the CO standard and provide 

for the implementation of RACM in the 

on-road motor vehicle category as 

required by CAA section 172(c)(1). See

EPA TSD section ‘‘Implementation of 

RACM for On-Road Motor Vehicle 

Controls—Technology.’’

CAA section 187(b)(2) requires a State 

with a serious CO nonattainment area to 

consider the TCMs in section 108(f) and 

choose to implement such measures as 

necessary to demonstrate attainment. 

The Phoenix area has a long history of 

adopting TCMs, including those in 

section 108(f), for controlling CO. The 

Revised 1999 CO Plan implements the 

section 108(f) TCMs and includes 

additional measures in support of the 

attainment demonstration. See Revised 

1999 CO Plan, Table 7–2 and Chapter 8. 

We therefore find that the Revised 1999 

CO Plan complies with CAA section 

187(b)(2) and 172(c)(1). See EPA TSD 

section ‘‘Implementation of RACM for 

On-Road Motor Vehicle Controls—

Transportation Control Measures.’’

The nonroad (mobile) engine category 

covers a diverse collection of engines, 

equipment and vehicles fueled by 

gasoline, diesel, and other fuels and 

includes outdoor power equipment, 

recreational equipment, farm 

equipment, construction equipment, 

lawn and garden equipment, aircraft, 

locomotives, and marine vessels. 

Although diesel engines dominate the 

market for nonroad engines, ninety 

percent of CO emissions from the 

nonroad category come from gasolinepowered nonroad engines.

Starting in the mid-1990s, EPA 

promulgated national emission 

standards for a broad range of nonroad 

engines. See EPA TSD section 

‘‘Implementation of RACM for Nonroad 

Engines.’’ Nonroad engines sold in 

Arizona are required to comply with 

these national standards which 

constitutes a RACM-level program for 

controlling emissions from nonroad 

engines. 

In addition, Arizona’s CBG program 

regulates gasoline used in nonroad 

engines. The Revised 1999 CO Plan also 

includes a number of other nonroad 

engine measures. See EPA TSD section 

‘‘Implementation of RACM for Nonroad 

Engines.’’ With the national emission 

standards and the additional State

60332 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

4This finding is further supported by our finding 

that the area attained the CO standard by December 

31, 2000. (68 FR 55008, effective November 21, 

2003).

measures, we find that the Revised 1999 

CO Plan provides for the 

implementation of RACM for nonroad 

engines. 

The residential wood combustion 

(RWC) category includes emissions from 

the burning of solid fuel in residential 

fireplaces and woodstoves as well as 

barbecues and fire pits. Measures to 

control CO from residential 

woodburning include a public 

education program, woodburning 

curtailment programs, retrofit 

requirements and restrictions or bans on 

the installation of woodburning stoves 

and/or fireplaces. 

The Maricopa County Environmental 

Services Department’s Rule 318, 

Approval of Residential Woodburning 

Devices, establishes standards for the 

approval of residential woodburning 

devices that can be used during 

restricted-burn periods. Maricopa 

County’s Residential Woodburning 

Restriction Ordinance provides that 

restricted-burn periods are declared by 

the Control Officer when the Control 

Officer determines that air pollution 

levels could exceed the CO standard 

and/or the PM standard (150 μg/m3). We 

approved Rule 318 and an earlier 

version of the ordinance (revised April 

21, 1999) as providing for the 

implementation of RACM. See 64 FR 

60678 (November 8, 1999). 

The Revised 1999 CO Plan includes a 

number of other woodburning measures. 

We find that these measures along with 

Maricopa County’s woodburning rules 

provide for the implementation of 

RACM for residential wood combustion. 

See EPA TSD section ‘‘Implementation 

of RACM for Residential Wood 

Combustion.’’

E. Demonstration of Attainment 

CAA section 187(a)(7) requires serious 

area plans to provide for attainment of 

the CO NAAQS by December 31, 2000 

and to contain a demonstration that the 

plan will provide for attainment. Under 

our guidance, an attainment 

demonstration may be made using EPAapproved air quality models and must 

include the control strategy. General 

Preamble at 13533. 

There are two parts to reviewing a 

modeled attainment demonstration: (1) 

Evaluating the technical adequacy of the 

modeling itself, and (2) evaluating the 

control measures that are relied on to 

demonstrate attainment. We discuss 

each part below. 

1. Air Quality Modeling

MAG used the Urban Airshed Model 

(UAM), the standard model for carbon 

monoxide attainment demonstrations, 

consistent with EPA guidance, to 

predict the effect of control measures in 

its attainment demonstration. UAM 

requires meteorological inputs, such as 

temperature and wind speeds, as well as 

initial and boundary conditions for CO 

concentrations, and CO emissions. 

These must be allocated in time and 

space; every hour of the simulation and 

every one square mile grid cell requires 

these inputs. Diagnostic testing is 

performed to ensure the model is 

performing well for a chosen CO 

episode, which in this case was 

December 17, 1994, which at 10.5 ppm 

had the highest CO peak and most 

widespread high CO readings observed 

during 1994. Once the model predicts 

observed CO concentrations for this 

chosen CO episode adequately, postcontrol measure emissions are input to 

the model to project future air quality. 

Separate predictions are also made ‘‘hot 

spots’’, intersections with high traffic 

and congested conditions, using the 

CAL3QHC model. This ‘‘microscale’’

component is then combined with the 

UAM results. The total prediction is 

then compared to the level of the 

NAAQS, 9.0 ppm, to demonstrate 

attainment. 

As detailed in the TSD, MAG 

followed accepted procedures in 

developing the model inputs, 

performing diagnostic testing of the 

results, and showing adequate model 

performance. Model performance 

statistics met EPA-recommended goals. 

The observed spatial and temporal 

patterns of CO were replicated fairly 

well by the model. While there were 

some discrepancies, these were 

attributed to lack of observations at 

some locations, and by slight shifts in 

wind patterns. That is, if the wind field 

input to the model had been slightly 

different, some high CO locations in the 

model predictions would have better 

matched the monitor locations. But 

since the magnitude, spatial extent, and 

timing of elevated CO concentrations is 

very similar between the model and 

observations, EPA determines the model 

performed adequately for attainment 

demonstration purposes. 

Overall, the modeling done by MAG 

meets EPA guidelines and performs well 

enough to be relied upon as the basis for 

the CO attainment demonstration. EPA 

therefore proposes to approve the CO 

attainment demonstration. 

2. Control Measures Relied on for 

Attainment 

For demonstrating attainment of the 

CO standard, the Revised 1999 CO Plan 

relies primarily on reductions from the 

VEI and CBG programs as well as much 

smaller reductions from three other 

measures, traffic synchronization, 

intelligent transportation systems, and 

deferring emissions associated with 

government activities. See Revised 1999 

CO Plan, Figure 9–1. We have 

previously approved all of these 

measures. See 68 FR 2912, 69 FR 10161, 

64 FR 60678, and 67 FR 48718. 

As part of these approvals, we have 

evaluated each of these measures to 

ensure that they meet our SIP 

enforceability criteria. These criteria 

ensure that the measure’s compliance 

requirements—applicability, 

performance standards, compliance 

schedule, and monitoring methods—are 

clear. 

We have also evaluated the CO 

emissions reductions credited to each 

measure in the attainment 

demonstration to ensure they are 

reasonable. We found that the emission 

reduction estimates for each source 

category are consistent with research on 

the applicable control methods and are 

appropriately applied in the attainment 

demonstrations. Finally, we have 

determined that the measures relied on 

for attainment are being expeditiously 

implemented. See EPA TSD, section 

‘‘Attainment Demonstration’’. 

F. Reasonable Further Progress 

CAA section 172(c)(2) requires 

nonattainment plans to provide for 

reasonable further progress (RFP), 

which is defined in section 171(1) as 

‘‘such annual incremental reductions in 

emissions of the relevant air pollutant as 

are required by this part [part D of title 

I] or may reasonably be required by the 

Administrator for the purpose of 

ensuring attainment of the applicable 

national ambient air quality standard by 

the applicable date.’’ For serious CO 

nonattainment areas, CAA section 

187(a)(7) also requires the plans to 

provide for such specific annual 

emission reductions as are necessary to 

attain the standard by the applicable 

attainment date.

We find that the Revised 1999 CO 

Plan provides for RFP and for such 

specific annual emission reductions as 

are necessary to attain the standard by 

the December 31, 2000 as required by 

the Act.4 The Revised 1999 CO Plan 

includes an RFP demonstration for the 

years 1994, 1999, and 2000. 1994 is the 

base year, 1999 is the year before the 

two largest measures in the Revised 

1999 CO Plan (revisions to the VEI and 

CBG programs) were implemented, and 

2000 is the attainment year. Total design 

day CO emissions drop from 687 mtpd

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60333

5See memorandum, G. T. Helms, Chief, Ozone/

Carbon Monoxide Programs Brand, OAQPS to Air 

Branch Chiefs, Regions I–X, ‘‘Early Implementation 

of Contingency Measures for Ozone and Carbon 

Monoxide (CO) Nonattainment Areas,’’ August 13, 

1993 (‘‘Helms memo’’).

6 In 1998/99, the program retired 1780 old, 

polluting gas mowers and 563 other pieces of 

garden equipment. See ‘‘Current Status of Carbon 

Monoxide,’’ Maricopa County Environmental 

Services Department, (January 2000).

in 1994 to 686 mtpd in 1999 to 640 

mtpd in 2000. Revised 1999 CO Plan, 

Figure 9–4. Total CO emissions drop 

very little from 1994 to 1999 primarily 

because a large increase in emissions 

from non-road engines offsets the 

decreases in on-road emissions. See 

MAG TSD, Table II–4.

G. VMT Tracking and Reporting 

CAA section 187(a)(2)(A) requires 

each State with a serious CO 

nonattainment area to forecast VMT in 

the nonattainment area for each year 

before the attainment year. These 

forecasts must be developed following 

guidance issued by EPA in consultation 

with the U.S. Department of 

Transportation. This section also 

requires the plan to provide for annual 

updates of the forecasts to be submitted 

along with a report containing estimates 

of actual VMT for the year. We provided 

detailed guidance to States regarding the 

VMT tracking and reporting 

requirement in ‘‘Section 187 VMT 

Forecasting and Tracking Guidance,’’

USEPA, January 1992. 

We find that the Revised 1999 CO 

Plan fully complies with CAA section 

187(a)(2)(A) and our guidance 

implementing that section. Specifically, 

the VMT forecasts in the Revised 1999 

CO Plan were developed consistent with 

applicable EPA guidance including (1) 

forecasting VMT using a validated 

network-based travel demand model; (2) 

clearly identifying a VMT tracking area; 

(3) estimating actual VMT on Highway 

Performance Monitoring System 

(HPMS) traffic counts adjusted in a 

reasonable manner to cover the entire 

VMT tracking area; and (4) committing 

to submitting annual reports meeting 

EPA requirements. 

MAG has submitted VMT tracking 

reports for the years 1999, 2000, and 

2001. These reports follow EPA 

guidance regarding content and 

procedures for determining actual VMT. 

All three reports show that VMT levels 

in the metropolitan Phoenix CO 

nonattainment area remain within the 

levels projected in the Revised 1999 CO 

Plan. See ‘‘1999 Vehicle Miles Travel 

Forecasting and Tracking Report,’’

MAG, September 22, 1999 (submitted 

September 23, 1999); ‘‘2000 Vehicle 

Miles Travel Forecasting and Tracking 

Report,’’ MAG, September 11, 2000 

(submitted September 21, 2000); and 

‘‘2001 Vehicle Miles Travel Forecasting 

and Tracking Report,’’ MAG, October 

23, 2001 (submitted November 14, 

2001).

H. Transportation Control Measures To 

Offset Growth in Emissions 

CAA section 187(b)(2) requires 

serious area CO plans to identify and 

adopt ‘‘specific and enforceable 

transportation control strategies and 

TCMs to offset any growth in emissions 

from growth in VMT and numbers of 

trips’’ and to achieve reductions in 

mobile source emissions as necessary in 

conjunction with other measures to 

comply with the applicable periodic 

emission reduction and attainment 

requirements. 

We interpret this provision to require 

that sufficient measures be adopted so 

that projected motor vehicle CO 

emissions will never be higher during 

the CO season in one year than during 

the CO season in the year before. Where 

growth in VMT and trips would 

otherwise cause a motor vehicle 

emissions upturn, this upturn must be 

prevented. General Preamble at 13521. 

The Revised 1999 CO Plan provides 

sufficient information for us to conclude 

that on-road mobile source emissions 

will decrease from the base year of 1994 

until the attainment year of 2000 and 

this decrease will occur even before we 

take into account the additional controls 

in the Revised 1999 CO Plan. Moreover, 

the Revised 1999 CO Plan provides for 

expeditious attainment of the CO 

standard. Therefore, we propose to find 

that the Revised 1999 CO Plan meets 

CAA section 187(b)(2). 

I. Contingency Measures 

CAA section 172(c)(9) requires that 

nonattainment area SIPs provide for the 

implementation of specific measures to 

be undertaken if the area fails to make 

RFP or attain by its attainment deadline. 

CAA section 187(a)(7) requires that 

serious CO nonattainment area plans 

also contain contingency measures that 

would be implemented if the area 

exceeds its vehicle mile traveled (VMT) 

projections. Both sections require that 

these contingency measures are to take 

effect without further action by the State 

or the Administrator. The Act does not 

specify how many contingency 

measures are necessary nor does it 

specify the magnitude of the emission 

reductions (or VMT reductions) they 

must produce. In policy and in previous 

rulemaking we have suggested that one 

appropriate choice of contingency 

measures would be to provide for the 

implementation of sufficient VMT 

reductions or emissions reductions to 

counteract the effect of one year’s 

growth in VMT in order to ensure 

continued progress while the plan was 

being revised to correct any deficiencies 

that resulted in a failure to attain, make 

RFP, or keep within VMT forecasts. 

General Preamble at 13532. 

Under applicable Agency policy, 

states may use already adopted and 

implemented measures as contingency 

measures, provided that those measures’

emission reductions are not needed to 

demonstrate expeditious attainment 

and/or RFP and are not included in 

either the attainment or RFP 

demonstrations. This approach 

effectively allows for the early 

implementation of contingency 

measures.5

The Revised 1999 CO Plan includes 9 

contingency measures, all of which have 

already been adopted and implemented. 

See Table Con-1 in the EPA TSD. 

Collectively these measures result in 

approximately a 4.1 percent reduction 

in total CO emissions in 2001 and 

provide emission reductions from each 

of the largest categories of CO emissions 

in the Phoenix area: woodburning, 

gasoline on-road vehicles, and gasoline 

nonroad engines. See Revised 1999 CO 

Plan, p. 9–12. 

The annualized VMT growth in the 

Phoenix area from 2000 to 2005 is 

projected to be 2.6 percent. On-road 

mobile source account for 67 percent of 

the 2000 base case (e.g., prior to control) 

CO inventory of 714.9 mtpd. Revised 

1999 CO Plan, p. 8–12. Therefore, one 

year’s growth in VMT is equivalent to 

0.67 × 2.6 percent or 1.7 percent (12.2 

mptd) of the 2000 base case inventory. 

One of the eight contingency 

measures listed in the Revised 1999 CO 

Plan is no longer applicable. Funding 

for the lawn mower reduction program 

ended in FY 2001. Prior to 2001, the 

program resulted in the retirement of a 

large number of gasoline-powered 

commercial and residential lawn 

mowers and other hand-held gasolinepowered equipment.6 However, because 

these lawnmowers have been 

presumably replaced with cleaner units 

earlier then they would otherwise have 

been replaced, the program will have 

continuing effects for several years after 

2000.

The use of an adopted and 

implemented federal program, the 

national LEV program, as a contingency 

measure is acceptable. The purpose of 

contingency measures is to assure 

continued progress towards attainment

60334 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

7However, if the federal program is delayed or 

does not generate the expected emission reductions, 

the State would have to revise its contingency 

measures to assure adequate emission reductions or 

face a finding of SIP inadequacy.

8The revised rules established new defined 

‘‘areas’’ for specifying the applicability of their 

requirements. The wintertime oxygenated gasoline 

requirements apply to ‘‘Area A’’, which was 

originally defined as the Maricopa County CO 

nonattainment area. As explained below, Arizona 

has made a number of changes to the definition of 

Area A to affect the applicability of the fuel 

requirements.

in an area while its SIP is being revised 

to correct for a failure to attain or to 

make RFP or to deal with higher than 

expected VMT growth. To the extent 

that federal programs provide for this 

continued progress and the State has not 

otherwise relied on the program to 

demonstrate attainment or RFP, the 

State may rely on that measure.7

We have approved the other seven 

contingency measures into the Arizona 

SIP in earlier rulemakings. See 67 FR 

48718 (July 25, 2002) and 68 FR 2912 

(January 22, 2003).

Because the contingency measures 

collectively provide for emission 

reductions consistent with EPA policy 

and meet the statutory requirement that 

they ‘‘take effect without further action 

by the State or the Administrator,’’ we 

propose to find that the Revised 1999 

CO Plan meets the CAA sections 

172(c)(9) and 187(a)(7) requirement for 

contingency measures. We also propose 

to find that the emissions reductions 

resulting from these contingency 

measures are not already accounted for 

in the Phoenix CO nonattainment area’s 

RFP or attainment demonstrations. 

J. Enhanced I/M Program 

CAA section 187(b)(6) requires that all 

serious CO nonattainment areas 

implement an enhanced I/M program 

which complies with EPA guidance. We 

issued our initial rule containing the 

requirements for enhanced I/M 

programs in 1992 and have amended 

those rules several times since. For more 

information on the requirements for 

enhanced I/M programs, see 60 FR 

22518 (May 8, 1995) (initial approval of 

Arizona’s enhanced and basic I/M 

program) and 67 FR 52433 (August 12, 

2002) (proposed approval of revisions to 

Arizona’s enhanced and basic I/M 

program). 

Arizona first submitted the legislation 

and regulations for the Maricopa County 

enhanced vehicle emission inspection 

program in 1994 as part of its moderate 

area plans for CO and ozone. 

Subsequently, Arizona made a number 

of modifications to its program 

including revising the testing protocol, 

requiring on-board diagnostic system 

testing, expanding the exemption to the 

latest five model years, changing the 

waiver provisions, and removing the 

remote sensing element of the program. 

The State resubmitted the program for 

approval in 2001. See 2001 I/M 

submittal. 

In a separate action, we approved 

Arizona’s vehicle emission inspection 

program for the Phoenix area as meeting 

the enhanced I/M program requirements 

of CAA section 187(b)(6) and our 

regulations. See 68 FR 2912 (January 22, 

2003). 

K. Wintertime Oxygenated Gasoline 

Program 

CAA section 211(m) requires states 

with CO nonattainment areas with 

design values of 9.5 ppm or higher to 

implement a wintertime oxygenated 

gasoline program requiring that gasoline 

contain not less than 2.7 percent oxygen 

by weight. All serious CO 

nonattainment areas, which by 

definition have design values exceeding 

the 211(m) thresholds, must include an 

oxygenated gasoline program in their 

SIPs. See also CAA § 187(b)(3). Under 

both 211(m) and 187(b)(3), the program 

is to apply to all gasoline sold, supplied, 

offered for sale or supply, dispensed, 

transported or introduced into 

commerce in the consolidated 

metropolitan statistical area (CMSA) or, 

if no CMSA exists, the metropolitan 

statistical area (MSA). 

1. History of State Program 

Arizona first adopted a wintertime 

oxygenated gasoline program in 1988, 

before sections 187(b) and 211(m) were 

added to the Act as part of the 1990 

Clean Air Act Amendments. The 

original State wintertime oxygenated 

gasoline program applied throughout 

Maricopa County and established a 

fairly complicated scheme of shifting 

averages and exemptions. In general, 

however, it required leaded gasoline to 

contain between 2.4 and 3.7 percent 

oxygen by weight and unleaded gasoline 

to contain between 1.9 and 3.7 percent 

oxygen by weight. The program applied 

from September 30 through March 31 of 

each year. EPA approved this program 

into the SIP finding the fuel control 

measure was not preempted under CAA 

section 211(c)(4) and would, in any 

event, provide necessary CO emission 

reductions. See 53 FR 30224 (Aug. 10, 

1988). 

The August 10, 1988 SIP approval, 

however, was vacated by the Ninth 

Circuit Court of Appeals in Delaney v. 

EPA, 898 F.2d 687 (9th Cir. 1990). In 

1991, in response to an order from the 

court, EPA disapproved the Maricopa 

CO SIP including the State’s wintertime 

oxygenated gasoline requirement. 56 FR 

5458 (Feb. 11, 1991). In its place, EPA 

adopted a FIP with an oxygenated 

gasoline program. EPA modeled the FIP 

program on the then newly adopted 

requirements in 211(m). It required all 

gasoline sold in the Maricopa 

nonattainment area to contain a 

minimum oxygen content of 2.7 percent 

by weight from October 1 to March 31 

of each year. In the FIP notice, we noted 

that section 211(m) added by the 1990 

Clean Air Amendments would require 

Maricopa to adopt a similar state 

requirement beginning in 1992. As a 

result, we anticipated that the 

oxygenated gasoline requirement in the 

FIP would only be in effect for one year.

Arizona adopted new oxygenated 

gasoline requirements on June 11, 1991 

in Arizona House Bill 2181. On March 

9, 1992, EPA approved Arizona’s 

revised wintertime oxygenated gasoline 

program into the SIP. 57 FR 8268. The 

revised program required that all 

gasoline in the Maricopa nonattainment 

area contain no less than 2.7 percent 

oxygen by weight from September 30 to 

March 31 of each year. In that approval, 

EPA noted that the area covered by the 

program did not include the entire MSA 

as required under section 211(m). 

Instead, the program applied only to the 

Maricopa CO nonattainment area, which 

was then defined as the MAG urban 

planning area. As a result, we found the 

State program could be approved into 

the SIP as an equivalent substitution for 

the FIP program but concluded that 

Arizona would need to modify the 

program further by November 1, 1992 in 

order to meet all the requirements of 

211(m). Id.

Since our March 1992 approval, 

Arizona has made a number of changes 

to the wintertime oxygenated gasoline 

program. In 1998, EPA approved 

changes to the wintertime program as 

part of our approval of the State’s new 

Cleaner Burning Gasoline (CBG) 

program. 63 FR 6653 (Feb. 10, 1998). 

The wintertime program approved at 

that time continued to require that 

gasoline supplied or sold in the 

Maricopa CO nonattainment area 8

contain a minimum 2.7 percent oxygen 

by weight, but changed the control 

period to November 1 through March 

31. In our approval, we did not address 

compliance with 211(m), instead 

finding the revisions necessary for 

attainment of the ozone and PM–10 

NAAQS.

On March 4, 2004, we approved into 

the SIP further revisions to the State 

CBG program, including changes to the 

wintertime oxygenated gasoline

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60335

9All of Pinal County was added to the definition 

of the Phoenix-Mesa MSA by the 1990 census.

requirements. 69 FR 10161. The current 

SIP-approved wintertime program 

requires all gasoline sold in Maricopa 

County and in parts of Pinal and 

Yavapai Counties from November 1 to 

March 31 to contain a minimum of 3.5 

percent oxygen by weight. Although 

Arizona’s wintertime CBG program 

adopted by the State on July 18, 1988 

covered the MSA, as required by 

211(m), subsequent changes to the 

covered area that have been approved 

into the SIP (i.e., the inclusion of 

portions of Yavapai and Pinal Counties) 

do not correspond to the entire MSA, 

which itself has been subsequently 

modified by the Census Bureau.9

2. Compliance With 211(m)

The State’s wintertime oxygenated 

gasoline program approved in the SIP 

has provided significant CO emissions 

reductions in the Maricopa CO 

nonattainment area and has helped the 

area attain the CO NAAQS, as 

evidenced by the Phoenix area’s lack of 

violations of the CO standard since 

1997, when the program was initiated. 

As a result, we are proposing to find 

that further changes to the program to 

meet the specific requirements of 

211(m), including the requirement that 

the program apply to the entire MSA, 

are not required under the Act. 

Section 211(m)(6) provides:

Nothing in this subsection shall be 

interpreted as requiring an oxygenated 

gasoline program in an area which is in 

attainment for carbon monoxide, except that 

in a carbon monoxide nonattainment area 

which is redesignated as attainment for 

carbon monoxide, the requirements of this 

subsection shall remain in effect to the extent 

such program is necessary to maintain such 

standard thereafter in the area.

See also CAA section 187(b)(3)(B) 

(providing that a wintertime oxygenated 

program is not required for an area if the 

State demonstrates that the revision is 

not necessary for attainment and 

maintenance of the CO NAAQS). We 

have interpreted this language to mean 

that once EPA determines that a CO 

nonattainment area is actually attaining 

the CO NAAQS and the area 

demonstrates it does not need a program 

meeting 211(m), section 211(m) no 

longer requires submittal of a SIP 

revision so long as the area continues to 

maintain the standard. See, e.g., 60 FR 

62741 (Dec. 7, 1995) (waiving 211(m) 

requirements for portions of the 

Camden, New Jersey area). 

Today’s finding that the State need 

not submit a program complying with 

section 211(m) does not mean the State 

can abandon its wintertime oxygenated 

gasoline program. The program remains 

approved in the SIP. Any revision to 

remove these requirements from the SP 

would be subject to the requirements of 

section 110(l). 

L. General SIP Requirements 

CAA section 110(a)(2)(C) requires 

SIPs to include a program to provide for 

the enforcement of SIP measures. 

Section 110(a)(2)(E)(i) requires that SIPs 

provide necessary assurances that the 

State (or the general purpose local 

government) will have adequate 

personnel, funding and authority under 

State law to implement the submitted 

SIP. Finally, section 110(a)(2)(E)(iii) 

requires SIPs to include necessary 

assurances that where a State has relied 

on a local or regional government, 

agency or instrumentality for the 

implementation of any plan provision, 

the State has responsibility for ensuring 

adequate implementation of the plan 

provision. 

The principal control measures in the 

Revised 1999 CO Plan are Arizona’s VEI 

program, the wintertime CBG program, 

and Maricopa County’s woodburning 

restrictions program. We approved these 

programs at 68 FR 2912 (January 12, 

2003), 69 FR 10161 (March 4, 2004), 64 

FR 60678, and 67 FR 48718 (July 25, 

2002) respectively. As part of our 

approval actions, we found that Arizona 

had adequate personnel, funding and 

authority to implement these programs 

and had adequately provided for the 

enforcement of these programs. 

We have previously found that 

Arizona law includes the necessary 

assurances that where a State has relied 

on a local or regional government 

agency or instrumentality for the 

implementation of any plan provision, 

the State has responsibility for ensuring 

adequate implementation of the plan 

provision. 60 FR 18010, 18019 (April 

10, 1995). 

V. The CAA’s Requirements for Serious 

CO Maintenance Plans and 

Redesignation Requests 

Under the Clean Air Act, we can 

change designations if acceptable data 

are available and if certain other 

requirements are met. See CAA Section 

107(d)(3)(D). Section 107(d)(3)(E) of the 

CAA provides that the Administrator 

may promulgate a redesignation of a 

nonattainment area to attainment if the 

following five criteria are met: 

(i) The Administrator determines that 

the area has attained the national 

ambient air quality standard;

(ii) The Administrator has fully 

approved the applicable 

implementation plan for the area under 

CAA section 110(k); 

(iii) The Administrator determines 

that the improvement in air quality is 

due to permanent and enforceable 

reductions in emissions resulting from 

implementation of the applicable 

implementation plan and the applicable 

Federal air pollutant control regulations 

and other permanent and enforceable 

reductions; 

(iv) The Administrator has fully 

approved a maintenance plan for the 

area as meeting the requirements of 

CAA section 175A; and 

(v) The State containing the area has 

met all requirements applicable to the 

area under section 110 and part D of the 

CAA. 

Before we can approve the 

redesignation request, we must 

determine that all applicable SIP 

elements have been fully approved. 

Approval of the applicable SIP elements 

may occur simultaneously with the final 

approval of the redesignation request. 

VI. The MAG CO Redesignation 

Request and Maintenance Plan’s 

Compliance With the CAA’s 

Requirements for CO Redesignation 

Requests and Maintenance Plans 

We are proposing to approve the MAG 

Carbon Monoxide Redesignation 

Request and Maintenance Plan for the 

Maricopa County Nonattainment Area, 

May 2003 (‘‘MAG CO Redesignation 

Request and Maintenance Plan’’). The 

MAG CO Redesignation Request and 

Maintenance Plan was developed by the 

Maricopa Association of Governments 

(MAG), the lead air quality planning 

agency in Maricopa County. The 

Arizona Department of Environmental 

Quality (ADEQ) submitted this plan as 

a revision to the Arizona SIP on June 16, 

2003 and EPA received it on June 24, 

2003. We refer to this plan in this 

document as the MAG CO redesignation 

request and maintenance plan, the MAG 

maintenance plan, or variations of these. 

As submitted, the MAG CO 

Redesignation Request and Maintenance 

Plan consists of the main plan 

document and one volume of technical 

appendices. The MAG CO 

Redesignation Request and Maintenance 

Plan contains 1994 and 1999 emission 

inventories and projected inventories 

for 2006 and 2015, a modeling 

demonstration showing maintenance of 

the CO standard through 2015, a list of 

committed control measures, mobile 

source emissions budgets for 2006 and 

2015, and contingency measures. It uses 

UAM and the CAL3QHC microscale 

model to model air quality in 1994 as 

a base year and in 2006 as an interim 

year and 2015 as the maintenance year

60336 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

and demonstrates maintenance of the 

CO standard through 2015. 

The MAG CO Redesignation Request 

and Maintenance Plan shows that the 

principal sources contributing to past 

CO exceedances are gasoline on-road 

motor vehicles, gasoline non-road 

engines, and woodburning. MAG CO 

Redesignation Request and Maintenance 

Plan, p. ES–5. 

In earlier actions, we have already 

approved revisions to Arizona’s CBG 

program and to Arizona’s VEI program 

as well as the Maricopa County 

Woodburning curtailment program. 69 

FR 10161 (March 4, 2004), 68 FR 2912 

(January 22, 2003), 64 FR 60678 

(November 8, 1999) and 67 FR 48718 

(July 25, 2002). The revisions to these 

programs are the principal controls 

relied on in the MAG CO Redesignation 

Request and Maintenance Plan to 

demonstrate attainment. We have also 

previously approved the commitments 

by the Phoenix area cities and towns to 

adopt and/or implement CO control 

measures. We approved these 

commitments as part of the serious area 

PM–10 plan approval on July 25, 2002 

at 67 FR 48718. See 40 CFR 

52.120(c)(100). 

We have reviewed the MAG CO 

Redesignation Request and Maintenance 

Plan and believe that proposing to 

approve the request is warranted, 

consistent with the requirements of 

CAA section 107(d)(3)(E). The following 

sections of this notice describe how the 

requirements of section 107(d)(3)(E) are 

addressed by the MAG submittal. 

A. General SIP Requirements 

Section 110(k) of the CAA addresses 

our actions on submissions of revisions 

to a SIP. The CAA requires States to 

observe certain procedural requirements 

in developing SIP revisions for 

submittal to us. Section 110(a)(2) of the 

CAA requires that each SIP revision be 

adopted after reasonable notice and 

public hearing. This must occur prior to 

the revision being submitted by a State 

to us.

MAG held a public hearing for the 

MAG CO Redesignation Request and 

Maintenance Plan on May 5, 2003. The 

MAG Regional Council adopted the 

MAG CO Redesignation Request and 

Maintenance Plan on May 28, 2003. 

These SIP revisions were adopted and 

submitted by ADEQ to us on June 16, 

2003. We received the submittal on June 

24, 2003. 

We have evaluated MAG’s submittal 

and have determined that the State met 

the requirements for reasonable notice 

and public hearing under section 

110(a)(2) of the CAA. The MAG CO 

Redesignation Request and Maintenance 

Plan was deemed complete by operation 

of law six months after the submittal 

date. 

B. Attainment of the CO NAAQS 

Section 107(d)(3)(E)(i) of the CAA 

states that for an area to be redesignated 

to attainment, the Administrator must 

determine that the area has attained the 

applicable NAAQS. As described in 40 

CFR part 50.8, the national primary 

ambient air quality standard for carbon 

monoxide is 9 parts per million (10 

milligrams per cubic meter) for an 8-

hour average concentration not to be 

exceeded more than once per year. 40 

CFR part 50.8 continues by stating that 

the levels of CO in the ambient air shall 

be measured by a reference method 

based on 40 CFR part 50, Appendix C 

and designated in accordance with 40 

CFR part 53. We consider an area to be 

in attainment if each of the CO ambient 

air quality monitors in the area does not 

have more than one exceedance of the 

CO standard over a one-year period. See 

40 CFR part 50.8 and 40 CFR part 50, 

Appendix C. If any monitor in the area’s 

CO monitoring network records more 

than one exceedance of the CO standard 

during a one-year calendar period, then 

the area is in violation of the CO 

NAAQS. 

In addition, our interpretation of the 

CAA and EPA national policy has been 

that an area seeking redesignation to 

attainment must show attainment of the 

CO NAAQS for at least a continuous 

two-year calendar period. In addition, 

the area must also continue to show 

attainment through the date that we 

promulgate the redesignation in the 

Federal Register. 

December 31, 2000 was the 

attainment date for the Maricopa County 

serious CO nonattainment area. We 

published a finding of attainment of the 

CO standard for the Maricopa County 

nonattainment area on September 22, 

2003 (see 68 FR 55008). In our finding, 

we noted that not only did Maricopa 

County have the required clean data for 

the two years preceding the attainment 

date, but also that the Maricopa County 

nonattainment area has been in 

attainment for the national standards for 

CO since 1997. Further information on 

CO monitoring is presented in Chapter 

3, page 3–15 of the MAG CO 

Redesignation Request and Maintenance 

Plan, and in our finding of attainment 

(see 68 FR 55008, September 22, 2003). 

Therefore, we believe the Maricopa 

County area has met the first component 

for redesignation: demonstration of 

attainment of the CO NAAQS. We note 

too that MAG has indicated in the MAG 

CO Redesignation Request and 

Maintenance Plan that ADEQ and 

MCESD will continue to operate an 

appropriate air quality monitoring 

network of National Ambient 

Monitoring Stations (NAMS) and State 

and Local Air Monitoring Stations 

(SLAMS) monitors in accordance with 

40 CFR Part 58 to verify the continued 

attainment of the CO standard. 

C. Meeting Applicable Requirements of 

Section 110 and Part D 

To be redesignated to attainment, 

section 107(d)(3)(E)(v) requires that an 

area must meet all applicable 

requirements under section 110 and part 

D of the CAA. We interpret section 

107(d)(3)(E)(v) to mean that for a 

redesignation to be approved by us, the 

State must meet all requirements that 

applied to the subject area prior to or at 

the time of submission of a complete 

redesignation request. 

1. CAA Section 110 Requirements 

The Maricopa County nonattainment 

area was initially classified as moderate 

for CO. MAG submitted the 1993 Carbon 

Monoxide Plan by November 15, 1993 

in order to meet the moderate area 

requirements. An addendum to this 

plan was submitted in March 1994. On 

July 29, 1996, the nonattainment area 

was reclassified to serious effective 

August 28, 1996 due to failure to attain 

the CO standard by December 31, 1995. 

The new attainment date was December 

31, 2000. 

On July 8, 1999, ADEQ submitted the 

1999 CO Plan to EPA. This submittal 

contained an attainment demonstration 

for December 2000. The submittal was 

found complete on September 9, 1999. 

During the 2000 legislative session, 

the Arizona Legislature passed House 

Bill (HB) 2104, which repealed the 

Random Onroad Testing Requirements 

(Remote Sensing Program) from the 

Vehicle Emissions Inspection (VEI) 

program. EPA indicated that the 1999 

CO Plan would have to be revised to 

reflect this legislative change. MAG 

conducted new air quality modeling and 

documented the impact of the repeal of 

the remote sensing program in the 

Revised 1999 CO Plan, dated March 

2001. 

On March 30, 2001, ADEQ submitted 

the Revised 1999 CO Plan to EPA. We 

found the submittal complete on 

October 9, 2001. We have analyzed the 

SIP elements in the Revised 1999 CO 

Plan that we are proposing for approval 

as part our action today, and have 

determined that they comply with the 

relevant requirements of section 

110(a)(2). 

On June 16, 2003, ADEQ submitted 

the MAG Carbon Monoxide 

Redesignation Request and

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60337

10See EPA’s September 4, 1992 John Calcagni 

memorandum entitled ‘‘Procedures for Processing 

Requests to Redesignate Areas to Attainment’’, and 

the General Preamble, 57 FR at 13564, dated April 

16, 1992.

11On August 9, 1993, EPA had issued a SIP call 

under section 110(k)(5) of the CAA that required 

Arizona to submit a plan to EPA that demonstrated 

attainment of the CO NAAQS in the Phoenix area 

by December 31, 1995. As an area with a design 

value less than 12.7 ppm, the State would not 

otherwise have been required to submit an 

attainment plan for the Phoenix area. See section 

187(a). CAA section 187(a)(1) requires the submittal 

of a comprehensive, accurate, current inventory of

Continued

Maintenance Plan for the Maricopa 

County Nonattainment Area, May 2003. 

The submittal was deemed complete by 

operation of law six months after receipt 

by EPA.

2. Part D Requirements 

Before the Maricopa County serious 

CO nonattainment area may be 

redesignated to attainment, the State 

must have fulfilled the applicable 

requirements of part D. Under part D, an 

area’s classification indicates the 

requirements to which it was subject. 

Subpart 1 of part D sets forth the basic 

nonattainment requirements applicable 

to all nonattainment areas. Subpart 3 of 

part D contains specific provisions for 

serious CO nonattainment areas. 

The relevant subpart 1 requirements 

are contained in sections 172(c) and 

176. Our General Preamble (see 57 FR 

13529, 13533, April 16, 1992) provides 

EPA’s interpretation of the CAA 

requirements for serious CO 

nonattainment areas. 

The General Preamble provides that 

the applicable requirements of CAA 

section 172 are 172(c)(3) [emissions 

inventory], 172(c)(5) [the section 

110(a)(2) air quality monitoring 

requirements], and 172(c)(9) 

[contingency measures]. It is also worth 

noting that we interpret the 

requirements of sections 172(c)(2) 

[reasonable further progress—RFP] and 

172(c)(6) [other measures] as being 

irrelevant to a redesignation request 

because they only have meaning for an 

area that is not attaining the standard.10

Finally, the State has not sought to 

exercise the options that would trigger 

sections 172(c)(4) [identification of 

certain emissions increases] and 

172(c)(8) [equivalent techniques]. Thus, 

these provisions are also not relevant to 

the redesignation request.

Regarding the requirements of 

sections 172(c)(3) [emissions inventory] 

and 172(c)(9) [contingency measures], 

please refer to our discussion below of 

sections 187(a)(1) and 187(a)(3), which 

are provisions of subpart 3 of part D of 

the CAA that address the same 

requirements as sections 172(c)(3) and 

172(c)(9). 

For the section 172(c)(5) New Source 

Review (NSR) requirements, the CAA 

requires all nonattainment areas to meet 

several requirements regarding NSR, 

including provisions to ensure that 

increased emissions will not result from 

any new or modified major stationary 

sources and a general offset rule. We 

have determined that areas being 

redesignated from nonattainment to 

attainment do not need to comply with 

the requirement that an NSR program be 

approved prior to redesignation 

provided that the area demonstrates 

maintenance of the standard without 

part D nonattainment NSR in effect. The 

rationale for this decision is described 

in a memorandum from Mary Nichols 

dated October 12, 1994 (‘‘Part D New 

Source Review (part D NSR) 

Requirements for Areas Requesting 

Redesignation to Attainment’’). We have 

determined that the maintenance 

demonstration for Maricopa County 

does not rely on nonattainment NSR. 

Therefore, the State need not have a 

fully-approved nonattainment NSR 

program prior to approval of the 

redesignation request. 

Prevention of Significant 

Deterioration (PSD) is the replacement 

for NSR, and part of the obligation 

under PSD is for a new source to review 

increment consumption and 

maintenance of the air quality 

standards. The PSD program requires 

stationary sources to undergo 

preconstruction review before facilities 

are constructed or modified, and to 

apply Best Available Control 

Technology (BACT). This program will 

apply to any major source wishing to 

locate in the Maricopa County area once 

the area is redesignated to attainment. 

Effective November 22, 1993, we 

delegated PSD authority to Maricopa 

County via a PSD Delegation Agreement 

(59 FR 1730, January 12, 1994). 

For the CAA section 172(c)(7) 

provisions [compliance with the CAA 

section 110(a)(2) air quality monitoring 

requirements], our interpretations are 

presented in the General Preamble (57 

FR 13535). CO nonattainment areas are 

to meet the applicable air quality 

monitoring requirements of section 

110(a)(2) of the CAA. 

Information concerning CO 

monitoring in the Maricopa County 

nonattainment area is included in the 

Monitoring Network Review (MNR) 

prepared by MCESD and submitted to 

EPA. In Chapter 3, page 3–15 of the 

MAG CO Redesignation Request and 

Maintenance Plan, MAG commits to the 

continued operation of the existing 

NAMS and SLAMS CO monitors run by 

ADEQ and MCESD, according to all 

applicable Federal regulations and 

guidelines, even after the Maricopa 

County area is redesignated to 

attainment for CO. Annual review of the 

NAMS/SLAMS air quality surveillance 

system will be conducted in accordance 

with 40 CFR 58.20(d) to determine 

whether the system continues to meet 

the monitoring objectives presented in 

Appendix D of 40 CFR Part 58.

Section 176 of the CAA contains 

requirements related to conformity. 

Although EPA’s regulations (see 40 CFR 

51.396) require that states adopt 

transportation conformity provisions in 

their SIPs for areas designated 

nonattainment or subject to an EPAapproved maintenance plan, we have 

decided that a transportation conformity 

SIP is not an applicable requirement for 

purposes of evaluating a redesignation 

request under section 107(d) of the 

CAA. This decision is reflected in EPA’s 

1996 approval of the Boston carbon 

monoxide redesignation (See 61 FR 

2918, January 30, 1996). 

The relevant subpart 3 provisions 

were created when the CAA was 

amended on November 15, 1990. The 

new CAA requirements for serious CO 

areas, such as Maricopa County, 

required that the SIP be revised to 

include a 1990 base year emissions 

inventory (CAA section 187(a)(1)), 

vehicle miles traveled tracking (CAA 

section 187(a)(2)(A)), contingency 

provisions (CAA section 187(a)(3)), 

corrections to existing motor vehicle 

inspection and maintenance (I/M) 

programs (CAA section 187(a)(4)), 

periodic emissions inventories (CAA 

section 187(a)(5)), enhanced motor 

vehicle I/M program (CAA section 

187(a)(6)), a modeled attainment 

demonstration with specific annual 

emissions reductions (CAA section 

187(a)(7)) and the implementation of an 

oxygenated fuels program (CAA section 

211(m)). How the State met these 

requirements and our approvals are 

described earlier in this notice. 

Regarding section 187(a)(1) of the 

CAA (base year emissions inventory), 

the State submitted a SIP revision for a 

1990 base year inventory (annual and 

average daily emissions) as well as 

projected 1995 and 2005 inventories for 

the entire Maricopa County 

nonattainment area on November 15, 

1993 as part of the MAG 1993 Carbon 

Monoxide Plan for the Maricopa County 

Area (‘‘CO Plan’’). On April 4, 1994, 

ADEQ submitted updated and improved 

inventories as part of MAG’s 1993 

Carbon Monoxide Plan for the Maricopa 

County Area Addendum

(‘‘Addendum’’).11 These revised

60338 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

actual emissions for all CO nonattainment areas 

whether or not they have a separate requirement to 

submit an attainment demonstration.

12Area A includes the urbanized portion of 

Maricopa County, a small portion of southern 

Yavapai County, and the western portions of Pinal 

County.

inventories reflected adjustments to 

growth factors and the impact of 

measures in Arizona House Bill 2001. 

Both submittals became complete by 

operation of law under CAA section 

110(k)(1)(B) on May 15, 1994 and 

October 8, 1994, respectively.

We proposed approval of the 1990 

base year inventory on September 18, 

1996 (61 FR 49087), and did not receive 

any comments on our proposed action. 

We will finalize that proposed action in 

our final rulemaking on today’s 

proposed rule. 

Regarding section 187(a)(5) of the 

CAA (periodic emissions inventories), 

see Section IV.B. ‘‘Emission Inventory’’

of this Federal Register notice for 

information on the 1993 and 1996 

emissions inventories for Maricopa 

County for CO. We are proposing to 

approve these inventories in our action 

today. 

D. Fully-Approved SIP Under Section 

110(k) of the CAA 

Section 107(d)(3)(E)(ii) of the CAA 

states that for an area to be redesignated 

to attainment, it must be determined 

that the Administrator has fully 

approved the applicable 

implementation plan for the area under 

section 110(k). 

As noted above, in today’s action EPA 

is approving the SIP revision 

demonstrating attainment for the 

Maricopa County serious CO 

nonattainment area that was required by 

the CAA. The bump-up of the Maricopa 

County CO nonattainment area from 

moderate to serious for CO superceded 

the remaining moderate CO 

nonattainment area requirements for the 

area. Thus, with a final rule to approve 

the Maricopa County attainment 

demonstration, redesignation request, 

and maintenance plan, we will have 

fully approved the Maricopa County CO 

element of the SIP under section 110(k) 

of the CAA. 

E. Improvement in Air Quality Due to 

Permanent and Enforceable Measures 

Section 107(d)(3)(E)(iii) of the CAA 

provides that for an area to be 

redesignated to attainment, the 

Administrator must determine that the 

improvement in air quality is due to 

permanent and enforceable reductions 

in emissions resulting from 

implementation of the applicable 

implementation plan, implementation 

of applicable Federal air pollutant 

control regulations, and other 

permanent and enforceable reductions. 

As part of our action today, we are 

approving the Revised 1999 CO Plan. 

This plan is primarily based on 

emissions reductions from the 

wintertime oxygenated fuels program, 

the VEI program, traffic 

synchronization, and intelligent 

transportation systems (ITS) measures. 

These programs are further described in 

Chapter Five of the Revised 1999 CO 

Plan. 

As described in Chapter Two, pages 

2–11 to 2–15 of the MAG CO 

Redesignation Request and Maintenance 

Plan, significant additional emissions 

reductions were realized from Maricopa 

County’s basic inspection and 

maintenance program (applicable to 

vehicles 1966 and newer), and 

beginning in 2000, the enhanced I/M 

program (applicable to vehicles 1966 

and newer, with an exemption for 

vehicles of the five most recent model 

years).

Oxygenated fuels are gasolines that 

are blended with additives that increase 

the level of oxygen in the fuel and 

consequently reduce CO tailpipe 

emissions. Arizona’s Cleaner Burning 

Gasoline (CBG) rule contains the 

oxygenated fuels provisions for the 

Maricopa CO nonattainment area. As 

approved by EPA on March 4, 2004 (see 

69 FR 10161), Arizona’s CBG program 

requires all Maricopa County-area gas 

stations in Area A 12 to sell fuels 

containing a 3.5 percent minimum 

oxygen content (by weight) during the 

wintertime season, which runs from 

November 2 to March 31 of each year.

Maricopa County has also been 

implementing the requirements of its 

clean burning fireplace ordinances. The 

Arizona legislature passed SB 1427 in 

1998 which required cities, towns, and 

counties in Area A to adopt, implement, 

and enforce an ordinance that complies 

with MAG’s clean burning fireplace 

standards by December 31, 1998. The 

ordinance allows only the use of 

permanently-installed gas or electric log 

inserts, fireplaces, woodstoves, or other 

appliances that are certified by EPA, 

tested and listed by a nationally 

recognized testing agency to meet 

federal performance standards, or 

determined by the Maricopa County 

Control Officer to meet federal 

performance standards. 

We have evaluated the various State 

and Federal control measures, the 

original 1990 base year emission 

inventory, and the 1993, and 1996 

periodic emissions inventories, and 

believe that the improvement in air 

quality in the Maricopa County 

nonattainment area has resulted from 

emissions reductions that are permanent 

and enforceable. 

F. Fully-Approved Maintenance Plan 

Under Section 175A 

Section 107(d)(3)(E)(iv) of the CAA 

provides that for an area to be 

redesignated to attainment, the 

Administrator must have fully approved 

a maintenance plan for the area meeting 

the requirements of section 175A of the 

CAA. 

Section 175A of the CAA sets forth 

the elements of a maintenance plan for 

areas seeking redesignation from 

nonattainment to attainment. The 

maintenance plan must demonstrate 

continued attainment of the applicable 

NAAQS for at least ten years after the 

Administrator approves a redesignation 

to attainment. Eight years after the 

promulgation of the redesignation, the 

State must submit a revised 

maintenance plan that demonstrates 

continued attainment for the subsequent 

ten-year period following the initial tenyear maintenance period. To address the 

possibility of future NAAQS violations, 

the maintenance plan must contain 

contingency measures, with a schedule 

for adoption and implementation, that 

are adequate to assure prompt 

correction of a violation. In addition, we 

issued further maintenance plan 

interpretations in the ‘‘General Preamble 

for the Implementation of Title I of the 

Clean Air Act Amendments of 1990’’ (57 

FR 13498, April 16, 1992), ‘‘General 

Preamble for the Implementation of 

Title I of the Clean Air Act Amendments 

of 1990: Supplemental’’ (57 FR 18070, 

April 28, 1992), and the EPA guidance 

memorandum entitled ‘‘Procedures for 

Processing Requests to Redesignate 

Areas to Attainment’’ from John 

Calcagni, Director, Air Quality 

Management Division, Office of Air 

Quality Planning and Standards, to 

Regional Air Division Directors, dated 

September 4, 1992 (hereafter referred to 

as the ‘‘Calcagni memo’’). In this 

Federal Register action, EPA is 

proposing approval of the maintenance 

plan for the Maricopa County CO 

nonattainment area because we believe, 

as detailed below, that MAG’s CO 

Redesignation Request and Maintenance 

Plan submittal meets the requirements 

of section 175A and is consistent with 

the documents referenced above. Our 

analysis of the pertinent maintenance 

plan requirements, with reference to 

MAG’s CO Redesignation Request and 

Maintenance Plan, is provided below.

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60339

1. Emissions Inventories—Attainment 

Year and Projections 

EPA’s interpretation of the CAA 

section 175A maintenance plan 

requirements are generally provided in 

the General Preamble (see 57 FR 13498, 

April 16, 1992) and the Calcagni memo 

referenced above. Under our 

interpretations, areas seeking to 

redesignate to attainment for CO may 

demonstrate future maintenance of the 

CO NAAQS either by showing that 

future CO emissions will be equal to or 

less than the attainment year emissions 

or by providing a modeling 

demonstration. However, under the 

CAA, many areas (such as Maricopa 

County) were required to submit a 

modeled attainment demonstration to 

show that reductions in emissions 

would be sufficient to attain the 

applicable NAAQS. For these areas, the 

maintenance demonstration is to be 

based on the same level of modeling 

(see the ‘‘Calcagni memo’’). For the 

Maricopa County area, this involved the 

use of EPA’s Urban Airshed Model 

(UAM) in conjunction with intersection 

hotspot modeling using the CAL3QHC 

model. 

The MAG CO Redesignation Request 

and Maintenance Plan submitted by 

ADEQ on June 16, 2003 included 

comprehensive emissions inventories of 

CO emissions for the Maricopa County 

area. These inventories include 

emissions from stationary point sources, 

area sources, non-road mobile sources, 

and on-road mobile sources. MAG used 

the 1994 base year inventory, from the 

Revised 1999 CO Plan received by EPA 

on April 2, 2001, and included an 

interim-year projection for 2006 along 

with the final maintenance year of 2015. 

More detailed descriptions of the 1994 

base year inventory from the Revised 

1999 CO Plan, the 2006 projected 

inventory, and the 2015 projected 

inventory are documented in the MAG 

redesignation request and maintenance 

plan on page 3–8, and in the State’s TSD 

in Appendix A, Exhibit 1. The State’s 

submittal contains detailed emission 

inventory information that was prepared 

in accordance with EPA guidance. 

Summary emissions figures from the 

1994 base year, the 2015 maintenance 

year and the interim projected year 2006 

are provided in Table 2 below.

TABLE 2.—SUMMARY OF CO EMISSIONS IN TONS PER DAY FOR MARICOPA COUNTY

[For a Friday in December] 

1994 2006 2015 

Point sources ........................................................................................................................................... 2.5 21.9 32.2 

Area sources ............................................................................................................................................ 21.0 29.7 36.2 

Non-road mobile sources ........................................................................................................................ 155.1 161.0 169.9 

On-road mobile sources .......................................................................................................................... 869.6 699.7 662.9 

Total * ................................................................................................................................................ 1048.2 912.3 901.2 

* Total may not equal 100% due to rounding. 

We note that based on the information 

in Table 2, minor increases are projected 

in years 2006 and 2015 for point sources 

and area sources. The most significant 

reductions in the emissions inventory 

come from the on-road mobile sources 

category. Since two of the MAG CO 

Redesignation Request and Maintenance 

Plan’s most significant measures reduce 

on-road vehicle emissions, namely the 

cleaner burning gasoline and vehicle 

emissions inspection programs, these 

projected emissions reductions are 

reasonable. MAG’s approach follows 

EPA guidance on projected emissions, 

and we believe it is acceptable. Further 

information on these projected 

inventories may also be found on page 

3–9 of the MAG CO Redesignation 

Request and Maintenance Plan and in 

Appendix A, Exhibit 2, Section III–1 of 

the TSD. 

2. Demonstration of Maintenance 

The Calcagni memo states that where 

modeling was relied on to demonstrate 

maintenance, the plan is to contain a 

summary of the air quality 

concentrations expected to result from 

the application of the control strategies. 

Also, the plan is to identify and describe 

the dispersion model or other air quality 

model used to project ambient 

concentrations. 

For the MAG CO maintenance 

demonstration, MAG used UAM, the 

standard model for 1-hour CO 

attainment demonstrations, consistent 

with EPA guidance in Guideline for 

Regulatory Application of the Urban 

Airshed Model for Areawide Carbon 

Monoxide (EPA–450/4–92–011a and b, 

June 1992; hereafter ‘‘Guideline’’). Most 

of the inputs for the modeling in the 

MAG CO Redesignation Request and 

Maintenance Plan were identical to 

those in the Revised 1999 CO Plan. The 

main differences were in mixing height 

and in the emissions inputs. 

In the MAG CO Redesignation 

Request and Maintenance Plan, the 

UAM model’s maximum model height 

was increased slightly to accommodate 

plume rise from growth in peaking 

power plants. This adjustment has a 

relatively small effect on ground-level 

CO concentrations. Diagnostic and 

sensitivity testing showed reasonable 

agreement with observations after 

adjustment of the DIFFBREAK 

parameter, which in UAM is similar to 

mixing height, the height above ground 

through which substantial mixing 

occurs. Adjustment of minimum mixing 

heights is not ideal, but may be 

unavoidable in the absence of specific 

measured data on mixing heights, and 

has been accepted in other CO plans. 

Since CO is chemically inert, it is not 

unreasonable to adjust the air volume 

available for CO dilution, and thereby 

adjust CO concentration. This assumes 

diagnostic testing for other model inputs 

has been done, as is the case here. 

MAG’s emission input development 

process used EPA’s MOBILE6 model to 

estimate on-road mobile source 

emission factors instead of MOBILE5, 

per EPA guidance, and newer traffic 

data were used. Total estimated CO 

emissions are substantially larger due to 

the changes in MOBILE model and 

various traffic and other inputs. On-road 

emissions for the 1994 episode 

increased 73%; total emissions from all 

sources increased 52%. However, 

modeled peak CO concentrations 

increased only slightly. Several factors 

account for the apparent discrepancy 

between input emissions and output 

model peak. 

First, per EPA guidance, MOBILE6 

was used to estimate on-road emissions 

instead of the older MOBILE5a. One 

effect mitigating the higher MAG CO 

maintenance plan emissions is that 

while the base case (1994) on-road 

emissions are higher, they decline faster 

than in the Revised 1999 CO Plan 

because of the enhanced effects of 

vehicle fleet turnover incorporated in 

MOBILE6. So higher initial emissions in

60340 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

the MAG CO Redesignation Request and 

Maintenance Plan are still consistent 

with maintenance of the CO NAAQS 

later. 

Second, the higher emissions in the 

MAG CO Redesignation Request and 

Maintenance Plan do not translate into 

increased peak CO concentrations. 

Mainly, the higher emissions in the 

MAG CO Redesignation Request and 

Maintenance Plan are shifted in time, 

and spread over a large area and 

volume; these mitigate the peakincreasing effect of the increased 

emissions. Revised traffic counts show 

that more of the emissions occur during 

the morning commute than during the 

evening. As a result, the increased 

emissions occur earlier in the day, 

farther from the peak in the 8-hour 

average, which occurs at 3 a.m. The 

assumed spatial distribution of cold 

start emissions was also different than 

in the Revised 1999 CO Plan. In the 

MAG CO Redesignation Request and 

Maintenance Plan, cold start emissions 

were distributed to local and arterial 

roads, but not to freeways; in the 

Revised 1999 CO Plan, the emissions 

were distributed to all three facility 

types. The method used in the MAG CO 

Redesignation Request and Maintenance 

Plan is more realistic because cold start 

emissions occur relatively close to the 

beginning of trips, when commuting 

cars are more likely to be on local roads 

than on freeways. Another effect of this 

different spatial allocation of emissions 

is that they are more dispersed. Because 

of this and because of changes in 

various other model inputs, CO 

emissions are more widely distributed 

in the MAG CO Redesignation Request 

and Maintenance Plan.

Finally, as mentioned above, mixing 

height was increased to improve model 

performance. This provided a greater 

volume for dilution of CO emissions, 

and thus a lower ambient concentration. 

A third factor in reconciling higher 

emissions with a relatively unchanged 

peak concentration is that, the MAG CO 

Redesignation Request and Maintenance 

Plan base case had less error and less 

negative bias than the Revised 1999 CO 

Plan’s, i.e., it underpredicted by a 

smaller amount. The highest CO at any 

monitor in the MAG CO Redesignation 

Request and Maintenance Plan was 

about 2% above the peak observation, 

whereas in the Revised 1999 CO Plan, 

it was 10% or more below. In summary, 

the increased emissions in the MAG CO 

Redesignation Request and Maintenance 

Plan did in fact show up in the 

modeling results, but the effect was not 

to increase the highest peak, but rather 

to increase concentrations more 

generally, distributed in time and space. 

For microscale modeling with 

CAL3QHC, the same intersections as in 

the Revised 1999 CO Plan were used, 

27th Ave./Grand/Thomas Rd. and 35th 

Ave./Grand/Indian School Road. For the 

attainment demonstration, the results of 

the CAL3QHC modeling were combined 

with that from UAM for the cell 

containing the intersection, per EPA 

guidance. CAL3QHC contributions to 

peak concentrations was generally lower 

than was modeled for the Revised 1999 

CO Plan. As discussed below, the 

decrease is partly due to updated traffic 

data. A shift in peak traffic to the 

morning occurred, which is further from 

the late-night CO peak. But the main 

reason for decreased CAL3QHC 

predictions was the exclusion of cold 

start emissions from idling emissions at 

intersections, in accordance with EPA 

guidance. Most cold start emissions 

occur within a few minutes of trip 

starts, so they have little affect on 

intersection emissions. Despite 

generally higher UAM predictions in the 

MAG CO Redesignation Request and 

Maintenance Plan, at the hotspot 

intersection locations, overall hotspot 

predictions are slightly lower. Table 3 

lists the maximum combined dispersion 

modeling (UAM) and intersection 

modeling (CAL3QHC) results for the 

maintenance demonstration modeling at 

the West Indian School Road and Grand 

Avenue intersections (from MAG CO 

Redesignation Request and Maintenance 

Plan, page 3–13).

TABLE 3.—MAXIMUM DISPERSION MODELING AND INTERSECTION MODELING RESULTS

[In parts per million] 

Intersection 

2006 2015 

UAM CAL3QHC Total UAM CAL3QHC Total 

WISR1 .............................................................................. 7.17 1.08 8.25 6.23 1.81 8.04 

Grand Ave ........................................................................ 7.74 0.50 8.24 7.16 0.65 7.81 

1West Indian School Road monitor. 

The target CO concentration for the 

maintenance demonstration modeling is 

9.0 ppm. MAG therefore needed to show 

that combined UAM and CAL3QHC 

concentrations remain below 9 ppm in 

2006 and 2015, despite the metropolitan 

area’s growth. The MAG modeling 

shows a maximum CO concentration of 

8.92 ppm in 2006, and 8.06 ppm in 

2015; these meet the maintenance goal 

of 9.0 ppm. 

For episode selection, modeling 

domain, wind fields, initial and 

boundary conditions, sensitivity testing 

was essentially identical between the 

two episodes (see the EPA TSD for the 

Revised 1999 CO Plan). The tests done 

showed that the model was responding 

reasonably. MAG’s modeling also meets 

EPA’s performance goals on peak level, 

peak timing, and absolute error. Model 

predictions in the MAG CO 

Redesignation Request and Maintenance 

Plan are closer to observations than in 

the Revised 1999 CO Plan modeling. 

Since the peak values and general 

spatial patterns match well and EPA’s 

model performance goals were met, 

overall the model appears to be 

replicating the episode fairly well, and 

forms an acceptable basis for a 

demonstration of maintenance. Overall, 

the modeling done by MAG for the CO 

maintenance demonstration performed 

adequately and meets EPA guidelines. 

EPA proposes to find the maintenance 

demonstration approvable.

3. Monitoring Network and Verification 

of Continued Attainment 

Continued attainment of the CO 

NAAQS in the Maricopa County area 

depends, in part, on the State’s efforts 

to track indicators throughout the 

maintenance period. This requirement 

is met in two sections of the MAG CO 

Redesignation Request and Maintenance 

Plan. On page 3–15 of the MAG CO 

Redesignation Request and Maintenance 

Plan, MAG commits to continue the 

operation of the CO monitors in the 

Maricopa County area and to annually 

review this monitoring network and 

make changes as appropriate. 

Also, on page 3–15 of the MAG CO 

Redesignation Request and Maintenance 

Plan, MAG commits to track mobile 

sources CO emissions (which are the

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60341

15 67 FR 46329 (July 12, 2002).

16The Maricopa County CO nonattainment area 

includes the portion of the Reservation that lies 

within Maricopa County, approximately the 

northern 25% of the Reservation.

largest component of the inventories) 

through the ongoing submittal of 

periodic emissions inventories every 

three years in accordance with section 

187(a)(5) of the CAA. MCESD will 

coordinate and compile the inventory 

with input and assistance from ADEQ, 

the Arizona Department of 

Transportation, and MAG, as described 

in the 1992 Air Quality Memorandum of 

Agreement. Changes in the inventory 

will be reviewed and evaluated through 

the regional air quality planning process 

to determine if additional measures 

should be considered. 

Based on the information above, we 

are proposing approval of these 

commitments as satisfying the relevant 

requirements of the CAA for 

maintenance plans. We note that a final 

rulemaking approval will render the 

State’s commitments federally 

enforceable. 

4. Contingency Plan 

Section 175A(d) of the CAA requires 

that a maintenance plan include 

contingency provisions. To meet this 

requirement, the State has identified 

appropriate contingency measures along 

with a schedule for the development 

and implementation of such measures. 

As stated on page 3–15 of the MAG 

CO Redesignation Request and 

Maintenance Plan, implementation of 

the contingency measures for the 

Maricopa County area will be triggered 

by two verified readings exceeding 9.0 

ppm at one monitor during a single CO 

season (i.e., October 1 through March 

31st). Since a violation of the NAAQS 

for 8-hour CO occurs when the second 

highest reading at the same monitor 

over two consecutive years is greater 

than or equal to 9.5 ppm, this trigger is 

more stringent than the standard, and 

will serve to prevent the occurrence of 

future violations. 

When the contingency measure trigger 

is activated, MAG will consider 

additional measures on the following 

schedule: (a) Verification of the 

monitoring data to be completed three 

months after activation of the trigger; (b) 

applicable measure to be considered for 

adoption six months after the date 

established in (a) above; and (c) the 

resultant measure to be implemented 

within six to twelve months, depending 

on the time needed to put the measure 

in place. 

5. Commitment To Submit Subsequent 

Maintenance Plan Revisions 

In accordance with section 175A(b) of 

the CAA, as the designated regional air 

quality planning agency for the 

Maricopa County area, MAG has 

committed to submit a revised 

maintenance plan eight years after 

redesignation. This provision for 

revising the maintenance plan is 

contained in Chapter 3, pages 3–16 to 3–

17 of the Maricopa County CO 

maintenance plan. 

VII. EPA’s Evaluation of the 

Transportation Conformity 

Requirements in the MAG CO 

Redesignation Request and 

Maintenance Plan 

One of the primary tests for 

conformity is to show that 

transportation plans and transportation 

improvement programs will not cause 

motor vehicle emissions to increase 

above levels needed to make progress 

towards and to meet air quality 

standards. The motor vehicle emissions 

levels needed to make progress toward 

and to meet the air quality standards are 

set in the area’s air quality plans as 

‘‘emissions budgets for motor vehicles’’. 

More details about conformity tests are 

described in section IV.A of this notice. 

EPA has been using a process and 

specific criteria for determining the 

adequacy of emissions budgets in 

control strategy SIPs since a 1999 court 

ruling. This process is now codified in 

a recent revision to the conformity rule 

(see 69 FR 40004, July 1, 2004). 

The MAG CO Redesignation Request 

and Maintenance Plan defines the CO 

motor vehicle emissions budgets in the 

Maricopa County area as 699.7 tons per 

day for 2006 and 662.9 tons per day for 

2015 and beyond. The budget for 2015 

is equal to the maintenance year (2015) 

mobile source emissions inventory for 

CO for the attainment/maintenance area. 

The MAG CO Redesignation Request 

and Maintenance Plan and supporting 

documentation indicate that the 662.9 

budget for 2015 is consistent with 

maintenance of the CO NAAQS 

throughout the maintenance period. 

Therefore, we are proposing to approve 

the 699.7 tons per day CO emissions 

budget for 2006 and the 662.9 tons per 

day CO emissions budget for 2015 for 

the Maricopa County nonattainment 

area. 

EPA’s adequacy determination on the 

MAG CO budgets for 2006 and 2015 was 

made in a letter to ADEQ and MAG on 

September 9, 2003 and was announced 

in the Federal Register on September 

29, 2003 (68 FR 55950). As a result of 

this adequacy finding, the 699.7 ton per 

day budget for 2006 and the 662.9 

budget for 2015 took effect for the 

conformity determinations in the 

Maricopa County nonattainment area on 

October 14, 2003. However, we are not 

bound by that determination in acting 

on the maintenance plan. 

VIII. GRIC Boundary Change Under 

CAA Section 107 

EPA is proposing to change the 

boundary of the Maricopa County CO 

nonattainment/maintenance area to 

exclude the Gila River Indian 

Reservation (‘‘Reservation’’). 

A. Background 

1. Current Area Boundary, Designation, 

and Classification

Areas of the country were originally 

designated as attainment, nonattainment 

or unclassifiable following enactment of 

the 1977 Amendments to the CAA. See

43 FR 8962 (March 3, 1978). These 

designations were generally based on 

monitored air quality values compared 

to the applicable NAAQS. The Maricopa 

County nonattainment area was 

designated a nonattainment area for CO 

in April 1977. The boundary for the 

Maricopa County CO nonattainment 

area was first established following the 

CAA Amendments of 1977. See 43 FR 

8962 (March 3, 1978) 

Under the 1990 Clean Air Act 

Amendments, the Maricopa County CO 

nonattainment area was again classified 

as a nonattainment area for CO. The 

nonattainment area boundary remained 

the same. 56 FR 6335 (November 6, 

1991). On August 28, 1996, the 

Maricopa County CO nonattainment 

area was reclassified to serious due to a 

failure to attain the 8-hour CO standard 

by December 31, 1995. 61 FR 39345 

(July 29, 1996) 

Area boundaries and area 

classifications have been amended over 

the years under the applicable CAA 

provisions, either by request of a state, 

by operation of law, or by EPA 

initiative. For the State of Arizona, the 

current area designations and 

classifications are codified at 40 CFR 

81.303. 

2. GRIC’s Request for a Boundary 

Change 

On July 14, 2004, the Gila River 

Indian Community (‘‘Community’’), a 

federally-recognized tribal 

government,15 submitted a formal 

request to EPA to revise the boundary of 

the Maricopa County CO nonattainment 

area to exclude the Reservation.16 The 

Community’s analysis of air quality data 

existing at the time of and subsequent 

to the designation in 1978 as well as the 

nature of the CO sources on the 

Reservation demonstrated that the 

Reservation has not had a monitored or

60342 Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 

17EPA could have applied CO limits to sources 

on the Reservation, as it has authority under CAA 

301(d) to promulgate regulations for Indian country 

as necessary or appropriate ‘‘to achieve the 

appropriate purpose’’ of the Act.

predicted violation of the CO NAAQS 

since, and that no significant sources of 

CO exist on the Reservation.

B. EPA Review of the Community’s 

Request 

1. EPA’s Authority to Change 

Boundaries 

Under section 107(d)(3)(A), EPA has 

the authority to revise the boundary of 

a nonattainment area on the basis of air 

quality data, planning and control 

considerations, or any other air qualityrelated considerations the Administrator 

deems appropriate. 

2. The Gila River Indian Reservation 

Airshed 

The Gila River Indian Reservation 

consists of approximately 374,000 acres 

in south central Arizona, south of the 

Phoenix metropolitan area. Currently, 

the Maricopa County (Phoenix area) CO 

nonattainment area includes the 

northern 92,000 acres of the 

Reservation. The Reservation is 

physically separated from the Phoenix 

metropolitan area by the Sierra Estrella 

and South Mountain Ranges. The Sierra 

Estrella Mountain Range runs north and 

south along the western edge of the 

Reservation. The South Mountain Range 

runs diagonally in a northeasterly 

direction, between one and five miles 

beyond the northern Reservation 

boundary. The mountain ranges act as a 

physical barrier between the two 

airsheds. 

A segment of the northern border of 

the Reservation adjacent to Chandler 

does not have a topographical barrier to 

air pollution transport. However, the 

prevailing winds flow to the northeast, 

sending CO emissions from Chandler 

away from the Reservation. Along the 

northeastern border of the Reservation, 

the Santan Mountain Range separates 

the Reservation from Gilbert and 

Apache Junction. 

The Reservation has a population of 

approximately 11,250 people, with a 

population density of approximately 20 

people per square mile. There are no 

major population centers within the 

Reservation. By comparison, Maricopa 

County (including vast rural areas west 

of the urban area which are not part of 

the nonattainment area) has a 

population of 2,122,101, with a 

population density of over 230 people 

per square mile. 

3. CO and the Reservation 

In general, ambient CO concentrations 

are caused by onroad and nonroad 

mobile emissions sources. The level of 

mobile source emissions can be directly 

correlated to population density and 

land use patterns. The Community 

population density of 20 people per 

square mile is minor compared to all of 

Maricopa County, which has a density 

of over 230 people per square mile. 

Commuting patterns on the Reservation 

are virtually nonexistent. 

Approximately 2200 cars, trucks and 

vans commute to work within the 

Reservation, compared to 1,250,000 in 

Maricopa County. There is little 

economic integration with commercial 

development in metropolitan Phoenix, 

and the Reservation remains largely 

rural and agricultural. The Community 

plans to expand its agricultural base by 

investing millions of dollars in 

agricultural infrastructure. 

Total annual emissions of CO on the 

Reservation are less than one percent of 

those in the MAG serious CO 

nonattainment area. High CO 

concentrations in the MAG 

nonattainment area are associated 

almost exclusively with areas of high 

traffic congestion, which do not exist on 

the Reservation. Therefore, there is 

substantial basis for concluding that the 

Reservation is an insignificant generator 

of CO emissions. 

4. CO Planning Issues 

Attainment of the CO NAAQS in the 

Phoenix metropolitan area was achieved 

by Arizona through the SIP planning 

process. It is important to note that, 

under the Clean Air Act, the state and 

local air pollution control authorities 

are not administering EPA-approved air 

regulatory programs over the 

Reservation; consequently, the SIP rules 

that were applied to the metropolitan 

area and resulted in attainment of the 

NAAQS did not apply to the 

Reservation. Furthermore, due to the 

Reservation’s lack of CO sources, it was 

never considered necessary to apply CO 

limits to sources in the Reservation.17

Just as it was clear that it was not 

necessary for an attainment plan to be 

applicable to the Reservation for the 

Phoenix area to attain the CO NAAQS, 

it is clear to EPA that it will not be 

necessary for a maintenance plan to be 

applicable to the Reservation for the 

Phoenix area to maintain attainment of 

the NAAQS. 

C. Redesignation of the Northern 

Portion of the Reservation 

In view of the above considerations, 

and because no CO air quality data 

exists for the Reservation, EPA believes 

‘‘nonclassifiable/attainment’’ is the 

appropriate designation for the entire 

Reservation, including that portion 

heretofore included in the 

nonattainment area. Therefore, EPA 

proposes to redesignate to 

‘‘nonclassifiable/attainment’’ the 

portion of the Reservation that is now 

within the nonattainment area, and 

make it part of the surrounding 

nonclassifiable/attainment area. 

IX. Proposed Action 

We are soliciting public comment on 

all aspects of this proposed SIP 

rulemaking action. We will consider 

your comments in deciding our final 

action if your comments are received by 

November 8, 2004.

We propose to approve the following 

elements of the Revised 1999 CO Plan 

for the metropolitan Phoenix area and 

the MAG CO Redesignation Request and 

Maintenance Plan: 

1. 1990 base year and 1993 and 1996 

periodic emission inventories as 

required by sections 172(c)(3) and 

187(a)(5). 

2. Demonstration that the plan 

provides for the implementation of 

reasonably available control measures 

including transportation control 

measures under sections 172(c)(1) and 

187(b)(2); 

3. Demonstration of attainment by 

December 31, 2000 under section 

187(a)(7); 

4. Demonstration of reasonable further 

progress under sections 172(c)(2) and 

187(a)(7); 

5. Contingency measures under 

sections 172(c)(9) and 187(a)(3); 

6. Forecasts of vehicle miles traveled 

and provisions for annual tracking and 

reporting under section 187(a)(2)(A); 

7. Transportation control measures as 

necessary to offset growth in emissions 

under section 187(b)(2); 

8. Attainment year and projected 

emissions inventories under section 

175A; 

9. Air quality monitoring 

requirements under section 110(a)(2) 

and section 172(c)(7); 

10. CO motor vehicle emissions 

budgets for transportation conformity 

under section 176(c) for the attainment 

demonstration and the maintenance 

plan for the years 2000, 2006 and 2015 

under the transportation conformity 

rule, 40 CFR Part 93, subpart A; 

11. Demonstration of maintenance 

under section 175A(a) and a fullyapproved maintenance plan under 

section 175A; 

12. Maintenance plan contingency 

measures under section 175A(d); 

13. Commitment for subsequent 

maintenance plan revisions under 

section 175A(b);

Federal Register / Vol. 69, No. 195 / Friday, October 8, 2004 / Proposed Rules 60343

14. Redesignation of that portion of 

the Gila River Indian Reservation that is 

now within the nonattainment area to 

‘‘nonclassifiable/attainment’; and 

15. A determination that the 

improvement in air quality in the 

Maricopa County nonattainment area is 

due to permanent and enforceable 

reductions in emissions resulting from 

the implementation of the applicable 

implementation plan, implementation 

of applicable Federal air pollution 

control regulations, and other 

permanent and enforceable reductions. 

We have previously approved all 

control measures relied on for 

attainment and contingency measures in 

the Revised 1999 CO Plan, including the 

area’s enhanced inspection and 

maintenance program (required by 

section 187(a)(6)), oxygenated gasoline 

program (required by sections 187(b)(3) 

and 211(m)), and woodburning 

curtailment regulations. See 68 FR 2912, 

69 FR 10161, 64 FR 60678 and 67 FR 

52416. 

As stated above, we are proposing 

approval of MAG’s June 16, 2003 

request to redesignate the Maricopa 

County CO nonattainment area to 

attainment and proposing approval of 

the maintenance plan for the Maricopa 

County CO nonattainment area. 

We are also proposing to change the 

designation of the portion of the Gila 

River Indian Community which is in the 

Maricopa County CO nonattainment 

area to ‘‘unclassifiable/attainment’’ for 

CO. 

X. Statutory and Executive Order 

Reviews 

Under Executive Order 12866 (58 FR 

51735, October 4, 1993), this proposed 

action is not a ‘‘significant regulatory 

action’’ and therefore is not subject to 

review by the Office of Management and 

Budget. For this reason, this action is 

also not subject to Executive Order 

13211, ‘‘Actions Concerning Regulations 

That Significantly Affect Energy Supply, 

Distribution, or Use’’ (66 FR 28355, May 

22, 2001). This proposed action merely 

proposes to approve state law as 

meeting Federal requirements and 

imposes no additional requirements 

beyond those imposed by state law. 

Accordingly, the Administrator certifies 

that this proposed rule will not have a 

significant economic impact on a 

substantial number of small entities 

under the Regulatory Flexibility Act (5 

U.S.C. 601 et seq.). Because this rule 

proposes to approve pre-existing 

requirements under state law and does 

not impose any additional enforceable 

duty beyond that required by state law, 

it does not contain any unfunded 

mandate or significantly or uniquely 

affect small governments, as described 

in the Unfunded Mandates Reform Act 

of 1995 (Public Law 104–4).

Executive Order 13175, entitled 

‘‘Consultation and Coordination with 

Indian Tribal Governments’’ (65 FR 

67249, November 6, 2000), requires EPA 

to develop an accountable process to 

ensure ‘‘meaningful and timely input by 

tribal officials in the development of 

regulatory policies that have tribal 

implications.’’ ‘‘Policies that have tribal 

implications’’ is defined in the 

Executive Order to include regulations 

that have ‘‘substantial direct effects on 

one or more Indian tribes, on the 

relationship between the Federal 

government and the Indian tribes, or on 

the distribution of power and 

responsibilities between the Federal 

government and Indian tribes.’’

Under section 5(b) of Executive Order 

13175, EPA may not issue a regulation 

that has tribal implications, that 

imposes substantial direct compliance 

costs, and that is not required by statute, 

unless the Federal government provides 

the funds necessary to pay the direct 

compliance costs incurred by tribal 

governments, or EPA consults with 

tribal officials early in the process of 

developing the proposed regulation. 

Under section 5(c) of Executive Order 

13175, EPA may not issue a regulation 

that has tribal implications and that 

preempts tribal law, unless the Agency 

consults with tribal officials early in the 

process of developing the proposed 

regulation. 

EPA has concluded that this proposed 

rule may have tribal implications. EPA’s 

action will remove the Gila River Indian 

Community from the Phoenix CO 

maintenance area. However, it will 

neither impose substantial direct 

compliance costs on tribal governments, 

nor preempt State law. Thus, the 

requirements of sections 5(b) and 5(c) of 

the Executive Order do not apply to this 

rule. 

Consistent with EPA policy, EPA 

nonetheless consulted with 

representatives of tribal governments 

early in the process of developing this 

regulation to permit them to have 

meaningful and timely input into its 

development. Representatives of tribal 

governments approached EPA two years 

ago and requested that EPA make this 

boundary change. We agree with the 

technical and policy rationale the tribe 

provided, and believe that all tribal 

concerns have been met. 

In the spirit of Executive Order 13175, 

and consistent with EPA policy to 

promote communications between EPA 

and tribal governments, EPA 

specifically solicits additional comment 

on this proposed rule from tribal 

officials. 

This action also does not have 

Federalism implications because it does 

not have substantial direct effects on the 

States, on the relationship between the 

national government and the States, or 

on the distribution of power and 

responsibilities among the various 

levels of government, as specified in 

Executive Order 13132 (64 FR 43255, 

August 10, 1999). This action merely 

proposes to approve a state rule 

implementing a Federal standard, and 

does not alter the relationship or the 

distribution of power and 

responsibilities established in the Clean 

Air Act. This proposed rule also is not 

subject to Executive Order 13045 

‘‘Protection of Children from 

Environmental Health Risks and Safety 

Risks’’ (62 FR 19885, April 23, 1997), 

because it is not economically 

significant. 

In reviewing SIP submissions, EPA’s 

role is to approve state choices, 

provided that they meet the criteria of 

the Clean Air Act. In this context, in the 

absence of a prior existing requirement 

for the State to use voluntary consensus 

standards (VCS), EPA has no authority 

to disapprove a SIP submission for 

failure to use VCS. It would thus be 

inconsistent with applicable law for 

EPA, when it reviews a SIP submission, 

to use VCS in place of a SIP submission 

that otherwise satisfies the provisions of 

the Clean Air Act. Thus, the 

requirements of section 12(d) of the 

National Technology Transfer and 

Advancement Act of 1995 (15 U.S.C. 

272 note) do not apply. This proposed 

rule does not impose an information 

collection burden under the provisions 

of the Paperwork Reduction Act of 1995 

(44 U.S.C. 3501 et seq.).

List of Subjects 

40 CFR Part 52 

Environmental protection, Air 

pollution control, Incorporation by 

reference, Intergovernmental relations, 

Reporting and recordkeeping 

requirements, Carbon monoxide. 

40 CFR Part 81 

Air pollution control, National parks, 

Wilderness areas.

Dated: September 21, 2004. 

Laura Yoshii, 

Acting Regional Administrator, Region 9.

[FR Doc. 04–22485 Filed 10–7–04; 8:45 am] 

BILLING CODE 6560–50–P