24280 Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 93 

[Docket No. OAR–2003–0049; FRL–7908–3] 

RIN 2060–AN03 

Transportation Conformity Rule 

Amendments for the New PM2.5

National Ambient Air Quality Standard: 

PM2.5 Precursors

AGENCY: Environmental Protection 

Agency (EPA).

ACTION: Final rule.

SUMMARY: This final rule adds the 

following transportation-related PM2.5

precursors to the transportation 

conformity regulations: nitrogen oxides 

(NOX), volatile organic compounds 

(VOCs), sulfur oxides (SOX), and 

ammonia (NH3). The final rule specifies 

when each of these precursors must be 

considered in conformity 

determinations in PM2.5 nonattainment 

and maintenance areas before and after 

PM2.5 state air quality implementation 

plans (SIPs) are submitted. Today’s 

action also makes a technical correction 

to a cross-reference of the U.S. 

Department of Transportation’s (DOT) 

planning regulations in the public 

consultation procedures of the 

conformity rule. The Clean Air Act 

requires federally supported highway 

and transit projects to be consistent with 

(‘‘conform to’’) the purpose of a SIP. 

EPA has consulted with DOT on the 

development of this final rule and DOT 

concurs with its content.

EFFECTIVE DATE: June 6, 2005.

ADDRESSES: Materials relevant to this 

rulemaking are in Public Docket I.D. No. 

OAR–2003–0049 located at the Air 

Docket, Environmental Protection 

Agency, Mailcode: 6102T, 1200 

Pennsylvania Ave., NW., Washington, 

DC 20460; phone: 202–566–1742. For 

more information about accessing 

information from the docket, see Section 

I.B. of the SUPPLEMENTARY INFORMATION

section.

FOR FURTHER INFORMATION CONTACT:

Rudy Kapichak, State Measures and 

Conformity Group, Transportation and 

Regional Programs Division, U.S. 

Environmental Protection Agency, 2000 

Traverwood Road, Ann Arbor, MI 

48105, e-mail address: 

kapichak.rudolph@epa.gov, telephone 

number: (734) 214–4574, fax number 

734–214–4052; or Angela Spickard, 

State Measures and Conformity Group, 

Transportation and Regional Programs 

Division, U.S. Environmental Protection 

Agency, 2000 Traverwood Road, Ann 

Arbor, MI 48105, e-mail address: 

spickard.angela@epa.gov, telephone 

number: (734) 214–4283, fax number 

734–214–4052.

SUPPLEMENTARY INFORMATION: The 

contents of this preamble are listed in 

the following outline:

I. General Information 

II. Background 

III. PM2.5 Precursors

IV. Technical Correction to Public 

Consultation Procedures 

V. How Does Today’s Final Rule Affect 

Conformity SIPs? 

VI. Statutory and Executive Order Reviews

I. General Information 

A. Does This Action Apply to Me? 

Entities potentially regulated by the 

conformity rule are those that adopt, 

approve, or fund transportation plans, 

programs, or projects under title 23 

U.S.C. or title 49 U.S.C. Regulated 

categories and entities affected by 

today’s action include:

Category Examples of regulated entities 

Local government ..................................................................................... Local transportation and air quality agencies, including metropolitan 

planning organizations (MPOs). 

State government ..................................................................................... State transportation and air quality agencies. 

Federal Government ................................................................................. Department of Transportation (Federal Highway Administration (FHWA) 

and Federal Transit Administration (FTA)). 

This table is not intended to be 

exhaustive, but rather provides a guide 

for readers regarding entities likely to be 

affected by this final rule. This table 

lists the types of entities of which EPA 

is aware that potentially could be 

regulated by the conformity rule. Other 

types of entities not listed in the table 

could also be regulated. To determine 

whether your organization is regulated 

by this action, you should carefully 

examine the applicability requirements 

in § 93.102 of the transportation 

conformity rule. If you have questions 

regarding the applicability of this action 

to a particular entity, consult the 

persons listed in the preceding FOR

FURTHER INFORMATION CONTACT section. 

B. How Can I Get Copies of This 

Document? 

1. Docket. Materials relevant to this 

rulemaking are in Public Docket I.D. No. 

OAR–2003–0049. The official public 

docket consists of the documents 

specifically referenced in this action, 

any public comments received, and 

other information related to this action. 

Although a part of the official docket, 

the public docket does not include 

Confidential Business Information (CBI) 

or other information whose disclosure is 

restricted by statute. The official public 

docket is the collection of materials that 

is available for public viewing at the Air 

Docket in the EPA Docket Center, (EPA/

DC) EPA West, Room B102, 1301 

Constitution Ave., NW., Washington, 

DC. The Docket telephone number is 

(202) 566–1742. The EPA Docket Center 

Public Reading Room is open from 8:30 

a.m. to 4:30 p.m., Monday through 

Friday, excluding legal holidays. The 

telephone number for the Public 

Reading Room is (202) 566–1744. You 

may have to pay a reasonable fee for 

copying docket materials. 

2. Electronic Access. You may access 

this Federal Register document 

electronically through EPA’s 

Transportation Conformity Web site at 

http://www.epa.gov/otaq/transp/

traqconf.htm. You may also access this 

document electronically under the 

Federal Register listings at http://

www.epa.gov/fedrgstr/.

An electronic version of the public 

docket is available through EPA’s 

electronic public docket and comment 

system, EPA Dockets. You may use EPA 

Dockets at http://www.epa.gov/edocket/

to view public comments, access the 

index listing of the contents of the 

official public docket, and to access 

those documents in the public docket 

that are available electronically. 

Although not all docket materials may 

be available electronically, you may still 

access any of the publicly available 

docket materials through the docket 

facility identified in Section I.B.1. Once 

in the EPA electronic docket system, 

select ‘‘search,’’ then key in the 

appropriate docket identification 

number. 

II. Background 

A. What Is Transportation Conformity? 

Transportation conformity is required 

under Clean Air Act section 176(c) (42 

U.S.C. 7506(c)) to ensure that federally 

Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 24281

1Section 93.102(b)(1) of the conformity rule 

defines PM2.5 and PM10 as particles with an 

aerodynamic diameter less than or equal to a 

nominal 2.5 and 10 micrometers, respectively.

supported highway and transit project 

activities are consistent with (‘‘conform 

to’’) the purpose of the state air quality 

implementation plan (SIP). Conformity 

currently applies to areas that are 

designated nonattainment, and those 

redesignated to attainment after 1990 

(‘‘maintenance areas’’ with plans 

developed under Clean Air Act section 

175A) for the following transportationrelated criteria pollutants: ozone, 

particulate matter (PM2.5 and PM10),1

carbon monoxide (CO), and nitrogen 

dioxide (NO2). Conformity to the 

purpose of the SIP means that 

transportation activities will not cause 

new air quality violations, worsen 

existing violations, or delay timely 

attainment of the relevant national 

ambient air quality standards (NAAQS 

or ‘‘standards’’).

B. What Is the History of the 

Transportation Conformity Rule? 

EPA’s transportation conformity rule 

establishes the criteria and procedures 

for determining whether transportation 

activities conform to the SIP. EPA first 

promulgated the transportation 

conformity rule on November 24, 1993, 

(58 FR 62188) and subsequently 

published a comprehensive set of 

amendments on August 15, 1997, (62 FR 

43780) that clarified and streamlined 

language from the 1993 rule. EPA has 

made other smaller amendments to the 

rule both before and after the 1997 

amendments.

On July 1, 2004, EPA published a 

final rule (69 FR 4004) that amended the 

conformity rule to accomplish three 

objectives. The final rule: 

• Provided conformity procedures for 

state and local agencies under the new 

ozone and PM2.5 air quality standards; 

• Incorporated existing EPA and U.S. 

Department of Transportation (DOT) 

federal guidance into the conformity 

rule consistent with a March 2, 1999, 

U.S. Court of Appeals decision; and 

• Streamlined and improved the 

conformity rule.

The July 1, 2004, final conformity rule 

incorporated most of the provisions 

from the November 5, 2003, proposal for 

conformity under the new ozone and 

PM2.5 standards (68 FR 62690). EPA is 

conducting its conformity rulemakings 

for the new standards in the context of 

EPA’s broader strategies for 

implementing the new ozone and PM2.5

standards. 

The July 2004 final rule also 

incorporated all of the amendments 

resulting from a separate June 30, 2003, 

proposal (68 FR 38974). This proposal 

addressed the March 2, 1999, court 

ruling by the U.S. Court of Appeals for 

the District of Columbia Circuit 

(Environmental Defense Fund v. EPA, et 

al., 167 F. 3d 641, D.C. Cir. 1999), and 

incorporated existing federal guidance 

consistent with the court decision. 

Most recently, on December 13, 2004, 

EPA published in the Federal Register

a supplemental notice of proposed 

rulemaking to the November 5, 2003, 

new standards conformity proposal 

entitled, ‘‘Options for PM2.5 and PM10

Hot-Spot Analyses in the Transportation 

Conformity Rule Amendments for the 

New PM2.5 and Existing PM10 National 

Ambient Air Quality Standards’’ (69 FR 

72140). In response to substantial 

comments received on the November 

2003 proposal, EPA, in consultation 

with DOT, proposed additional options 

for PM2.5 and PM10 hot-spot 

requirements and requested comment 

on them as well as on the options 

presented in the November 2003 

proposal. Subsequently, EPA extended 

the public comment period for this 

supplemental proposal, to January 27, 

2005. EPA has not yet taken final action 

on the December 13, 2004 supplemental 

proposal. We are currently reviewing 

the public comments received on the 

supplemental proposal and will be 

issuing a final rule in the near future. 

C. Why Are We Issuing This Final Rule? 

In the November 5, 2003, proposal, 

EPA proposed options for addressing 

PM2.5 precursors in the conformity 

process. However, EPA did not finalize 

PM2.5 precursor requirements in the 

subsequent July 1, 2004, final rule 

because EPA had not proposed a 

broader PM2.5 implementation rule to 

seek comment on options for addressing 

PM2.5 precursors in the New Source 

Review program and in SIP planning 

activities such as reasonable further 

progress plans, attainment 

demonstrations, reasonably available 

control technology (RACT) 

requirements, and reasonably available 

control measures (RACM) analyses. At 

that time, EPA believed that it would 

have been inappropriate to select a final 

option for precursors in transportation 

conformity determinations prior to the 

development of the precursor options in 

the broader PM2.5 implementation rule 

proposal. While EPA has not yet 

proposed the PM2.5 implementation 

strategy, EPA has moved ahead with 

PM2.5 designations and this action has 

caused us to re-evaluate the need to 

defer finalization of the PM2.5 precursor 

requirements for transportation 

conformity until the implementation 

rule is proposed. Our re-evaluation is 

based on the fact that the one-year 

conformity grace period began on April 

5, 2005, the effective date of the 

designations. EPA believes that it is 

crucial that PM2.5 nonattainment areas 

be aware of the requirements for PM2.5

precursors at the beginning of the oneyear grace period in order to facilitate 

completion of all necessary work to 

determine conformity by the end of the 

grace period for all applicable 

precursors. Therefore, EPA has decided 

to finalize the transportation conformity 

requirements for PM2.5 precursors in 

advance of proposing the PM2.5

implementation rule. Although the 

implementation rule has not yet been 

proposed, on-going consideration of 

issues related to precursors in the 

implementation rule have been 

coordinated with development of this 

final rule.

EPA’s implementation strategy for the 

PM2.5 standard will include options for 

addressing PM2.5 precursors in other air 

quality planning programs (e.g., New 

Source Review for stationary sources). 

The public will have the opportunity to 

comment on these options during the 

comment period for that rulemaking 

once it is published in Federal Register. 

In today’s final rule, EPA addresses 

all public comments on the PM2.5

precursor options included in the 

November 2003 conformity proposal 

that were received during the comment 

period for that rulemaking. The 

comment period for the November 2003 

conformity proposal ended on 

December 22, 2003. 

Today’s final rule should not be 

interpreted as prejudging our decision 

on the PM2.5 precursor requirements 

that will soon be proposed in the PM2.5

implementation rulemaking. Our final 

rule for the implementation proposal 

will reflect how PM2.5 precursors should 

best be considered in other air quality 

planning programs and the comments 

received on that proposal. While EPA’s 

final decisions on PM2.5 precursors must 

be legally consistent, EPA could take 

differing positions with respect to 

various precursors in other programs as 

appropriate to the programmatic needs, 

legal requirements and pollution 

sources relevant to the differing 

programs. 

EPA notes, however, that if in the 

future we change our legal rationale for 

considering PM2.5 precursors among the 

various air quality planning programs 

from the positions currently under 

consideration as a result of comments 

received on the PM2.5 implementation 

strategy proposal, such changes could 

necessitate a subsequent revision to the 

transportation conformity rule. In the 

24282 Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 

case where an amendment to the 

conformity regulations is needed to 

reflect an alternative approach to 

considering PM2.5 precursors, EPA 

would conduct such a revision through 

full public notice and comment 

rulemaking. 

DOT is our federal partner in 

implementing the transportation 

conformity regulations. We have 

consulted DOT in developing this final 

rule and DOT concurs with its content. 

D. How Does This Final Rule Affect the 

One-Year Conformity Grace Period? 

As explained in the July 1, 2004, final 

rule that addresses the conformity 

requirements for the 8-hour ozone and 

PM2.5 standards (69 FR 40004), 

conformity applies one year after the 

effective date of EPA’s initial 

nonattainment designation for a given 

pollutant and standard. On January 5, 

2005 (70 FR 943), EPA designated areas 

as attainment and nonattainment for the 

PM2.5 air quality standard. These 

designations became effective on April 

5, 2005, 90 days after EPA’s published 

action in the Federal Register. 

Therefore, conformity for the PM2.5

standard will apply on April 5, 2006. 

Today’s final rule does not change the 

one-year conformity grace period for 

any area recently designated 

nonattainment for the PM2.5 standard. 

On April 5, 2006, metropolitan PM2.5

nonattainment areas must have in place 

a transportation plan and transportation 

improvement program (TIP) that 

conforms in accordance with the PM2.5

precursor requirements finalized by 

today’s action and the requirements 

previously finalized by the July 1, 2004, 

rulemaking. See the July 1, 2004, final 

rule (69 FR 40008 through 40014) for 

more information on the 

implementation of the one-year 

conformity grace period in newly 

designated PM2.5 nonattainment areas. 

III. PM2.5 Precursors 

A. Description of the Final Rule 

Today’s final rule identifies four 

transportation-related PM2.5

precursors—nitrogen oxides (NOX), 

volatile organic compounds (VOCs), 

sulfur oxides (SOX), and ammonia 

(NH3)—for consideration in the 

conformity process in PM2.5

nonattainment and maintenance areas. 

Once a PM2.5 SIP is submitted, a 

regional emissions analysis would be 

required for a given precursor if the SIP 

establishes an adequate or approved 

budget for that particular precursor. 

The November 5, 2003, notice of 

proposed rulemaking contained two 

options for addressing PM2.5 precursors 

in conformity determinations made 

before a SIP is submitted and emissions 

budgets are found adequate or 

approved. EPA is finalizing a modified 

version of the proposed options in this 

final rule. Specifically, a regional 

emissions analysis is required for NOX

as a PM2.5 precursor in all PM2.5

nonattainment areas, unless the head of 

the state air agency and the EPA 

Regional Administrator make a finding 

that NOX is not a significant contributor

to the PM2.5 air quality problem in a 

given area. Regional emissions analyses 

are not required for VOC, SOX or 

ammonia before an adequate or 

approved SIP budget for such precursors 

is established, unless the head of the 

state air agency or EPA Regional 

Administrator makes a finding that onroad emissions of any of these 

precursors is a significant contributor.

Prior to EPA finding the budgets from 

the submitted PM2.5 SIP adequate or 

approving the PM2.5 SIP, the MPO and 

DOT will document in their conformity 

determinations that a regional emissions 

analysis has not been conducted for 

NOX when EPA and the state air agency 

have determined NOX to be 

insignificant. The regulatory text for this 

final rule can be found in 

§§ 93.102(b)(2)(iv) and (v) and 

93.119(f)(9) and (10). 

A state air agency and/or EPA finding 

of significance or insignificance (a 

‘‘significance finding’’) for a PM2.5

precursor will be based on criteria 

similar to the general criteria for 

insignificance of motor vehicle 

emissions in § 93.109(k) of the 

conformity rule. Specifically, the 

following criteria will be considered in 

making significance or insignificance 

findings for PM2.5 precursors: The 

contribution of on-road emissions of the 

precursor to the total 2002 baseline SIP 

inventory; the current state of air quality 

for the area; the results of speciation 

monitoring for the area; the likelihood 

that future motor vehicle control 

measures will be implemented for a 

given precursor; and projections of 

future on-road emissions of the 

precursor. Determining the significance 

or insignificance of motor vehicle 

emissions in a given area will be 

conducted on a case-by-case basis.

Significance and insignificance 

findings will be made only after 

discussions among the interagency 

consultation partners for the PM2.5

nonattainment area. These discussions 

should include a review of the available 

data being considered to support the 

significance finding. Interagency 

consultation also ensures that all of the 

relevant agencies are aware that such a 

finding is being considered. It is 

important to provide transportation 

agencies with adequate notice of which, 

if any, precursors they may need to 

address in conformity analyses. A 

significance finding will be made 

through a letter from the state air agency 

or EPA regional office to the relevant 

state and local air quality and 

transportation agencies, MPO(s), DOT 

and EPA (in the case of a state air 

agency finding). An insignificance 

finding will be made through either 

letters from the state air agency and the 

EPA regional office or a letter co-signed 

by the state air agency and the EPA 

regional office to the relevant state and 

local air quality and transportation 

agencies, MPO(s) and DOT. 

EPA notes that any significance or 

insignificance finding made prior to 

EPA’s adequacy finding for budgets in a 

SIP, or EPA’s approval of the SIP, 

should not be viewed as the ultimate 

determination of the significance of 

precursor emissions in a given area. 

State and local agencies may find 

through the SIP development process 

that emissions of one or more precursors 

are significant, even if a precursor had 

previously been considered 

insignificant. In such a case, the PM2.5

SIP would establish a motor vehicle 

emissions budget for that precursor and 

a regional emissions analysis for that 

precursor would be included in 

subsequent conformity determinations. 

Alternatively, state and local agencies 

may find through the SIP development 

process that emissions of one or more 

precursors are insignificant even if a 

precursor had previously been 

considered significant. In such a case, 

the PM2.5 SIP would not establish a 

motor vehicle emissions budget for that 

precursor and a regional emissions 

analysis for that precursor would not be 

necessary in subsequent conformity 

determinations. 

To calculate emission factors for PM2.5

precursors, areas must use the latest 

EPA-approved motor vehicle emissions 

factor model (currently MOBILE6.2 for 

all states except California). PM2.5

nonattainment and maintenance areas 

in California must use EMFAC2002 or a 

more recently EPA-approved model. It 

should be noted that EMFAC2002 does 

not calculate emissions factors for 

ammonia. However, EPA understands 

that California is developing a 

methodology for estimating ammonia 

emissions from on-road vehicles. It is 

anticipated that this methodology will 

be completed prior to the end of the 

one-year conformity grace period. 

However, as a practical matter, 

conformity for ammonia would not be 

required in California until there is an 

acceptable method for estimating such 

Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 24283

2The speciation trends network consists of over 

50 monitoring sites in urban areas and provides 

nationally consistent data on PM2.5 constituents by 

type (i.e., ‘‘speciated’’) including nitrates, elemental 

carbon, organic carbon and sulfates.

3 In addition, California has adopted its own rule 

which addresses the sulfur content of gasoline in 

that State. California’s regulation is similar in 

stringency to the Federal regulation.

4EPA 420–R–00–020, October 2002, ‘‘Procedures 

for Developing Base Year and Future Year Mass and 

Modeling Inventories for the Heavy-Duty Engine 

and Vehicle Standards and Highway Diesel Fuel 

(HDD) Rulemaking.’’

emissions, because a method would be 

needed to estimate current or future 

ammonia emissions for either a 

significance finding or SIP motor 

vehicle emissions budget. 

B. Rationale for This Final Rule 

Section 176(c)(1)(B) of the Clean Air 

Act requires that federal funding and 

approval be given only to transportation 

activities that are consistent with state 

and local air quality goals. To fulfill this 

requirement with respect to PM2.5, EPA 

is requiring that transportation 

conformity determinations consider 

PM2.5 precursors if they are significant 

contributors to an area’s PM2.5 air 

quality problem. 

Today’s final rule incorporates NOX, 

VOCs, SOX, and ammonia as possible 

transportation-related PM2.5 precursors 

because all of these precursors are 

emitted from on-road motor vehicles. 

Based on data collected from monitoring 

sites in the national speciation trends 

network,2 secondary particles from 

precursors commonly account for over 

half of the total fine particle mass from 

all emissions sources measured at these 

sites. Therefore, we expect that areas 

may need to address on-road emissions 

of relevant precursors (i.e., NOX, VOC, 

SOX and ammonia) in their SIPs and in 

conformity.

The final rule allows for the 

consideration of the four precursors in 

conformity prior to PM2.5 SIPs when 

such precursors are significant: NOX is 

considered significant in the absence of 

a finding; VOCs, SOX and ammonia 

must be found significant to be 

included. In finalizing this rule EPA 

attempted to strike a balance between: 

(1) Expeditiously addressing 

transportation-related emissions that 

could exacerbate the PM2.5 air quality 

problem before a SIP is established, and 

(2) targeting conformity requirements in 

PM2.5 areas in an efficient and 

reasonable manner. 

EPA based its decision on a number 

of factors. For example, EPA considered 

the environmentally conservative nature 

of requiring conformity determinations 

for all four precursors prior to the 

submission of a SIP unless a finding is 

made that on-road emissions of a 

precursor or precursors is insignificant, 

rather than only for NOX. Requiring that 

all four precursors be addressed in 

conformity prior to the submission of a 

SIP may be a more environmentally 

protective approach to meeting the 

Clean Air Act’s conformity requirements 

because any significant precursors 

would automatically be addressed 

without the need for a significance 

finding to be made by the state air 

agency or the EPA regional office. On 

the other hand, requiring significance 

findings for the precursors VOCs, SOX

and ammonia better accounts for 

regional variability in air quality and 

better targets resources to the precursors 

that are most important in an individual 

area. Also, requiring significance 

findings for these three precursors could 

help areas avoid adopting on-road 

control measures to address a particular 

precursor before a SIP is submitted that 

ultimately prove to be unnecessary after 

a SIP is developed, if emissions of the 

targeted precursor are ultimately found 

to be insignificant. In addition, EPA also 

considered with respect to each 

precursor the chemistry of secondary 

particle formation, the results of 

speciated air quality monitoring and onroad emissions inventory data. In 

addition to the information provided 

below, the November 2003 notice of 

proposed rulemaking contains a more 

detailed discussion of speciated air 

quality data and on-road emissions data 

(68 FR 62706 through 62708). Please 

refer to the notice of proposed 

rulemaking for additional details.

Sulfur dioxide. While speciated air 

quality data show that sulfate is a 

relatively significant component (e.g., 

ranging from nine to 40 percent) of 

PM2.5 mass in all regions of the country, 

emissions inventory data and 

projections show that on-road emissions 

of SOX constitute a ‘‘de minimis’’ (i.e., 

extremely small) portion of total SOX

emissions. Emissions inventory data for 

1999 for the 372 potential PM2.5

nonattainment counties for PM2.5 (based 

on 1999–2001 air quality data) show 

that on-road sources were responsible 

for only two percent of total SOX

emissions. By comparison, fuel 

combustion sources (e.g., electric utility 

and industrial combustion of coal and 

oil) contributed approximately 88 

percent of the SOX emissions in 1999 in 

these same counties. 

Furthermore, EPA has already 

adopted two regulations that will greatly 

reduce emissions of SOX from on-road 

sources by the time such regulations are 

both in full effect in 2009. First, in 2004 

the low sulfur gasoline program began 

to be phased in and will be fully 

effective in 2007 (February 10, 2000, 65 

FR 6697). This regulation will reduce 

the sulfur content of gasoline by 

approximately 90 percent when fully 

effective.3 Second, in 2006 the low 

sulfur diesel program will begin to be 

phased in and will be fully effective by 

2009 (January 18, 2001, 66 FR 5001). 

This regulation will reduce the sulfur 

content of diesel fuel by approximately 

97 percent nationally when fully 

effective.

Projections of on-road emissions of 

SO2 in 2020 indicate that on-road 

sources will be responsible for less than 

one percent of the total SO2 emissions 

in 2020 in the 372 potential PM2.5

nonattainment counties (based on 1999–

2001 air quality data).4 These 

projections confirm that the 

implementation of the fuel regulations 

discussed above will ensure that as a 

general matter SO2 emissions from onroad sources remain at insignificant 

levels in all areas. Therefore, states are 

not required to include SOX in 

conformity determinations prior to 

submission of a SIP unless the state air 

agency or EPA regional office makes a 

finding that on-road emissions of SOX

are a significant contributor to an area’s 

PM2.5 problem. If a state determines 

through its SIP development process 

that on-road emissions of SOX are 

significant and the SIP includes an 

adequate or approved emissions budget 

for SOX, then future conformity 

determinations will be required to 

include a regional emissions analysis for 

SOX.

Nitrogen oxides. Based on a review of 

speciated monitoring data analyses, 

nitrate concentrations vary significantly 

across the country. For example, in 

some southeastern locations, annual 

average nitrate levels range from six to 

eight percent of total PM2.5 mass, 

whereas nitrate comprises 40 percent or 

more of PM2.5 mass in certain California 

locations. Nitrate formation is favored 

by the availability of ammonia, low 

temperatures, and high relative 

humidity. Nitrate formation also 

depends upon the amount of nearby SO2

emissions because ammonia reacts 

preferentially with SO2 over NOX (i.e., 

ammonia first reacts to form ammonium 

sulfate and then reacts to form 

ammonium nitrate). 

The sources of NOX are numerous and 

widespread, including motor vehicles, 

power plants, and many other 

combustion activities. We believe these 

source categories and the potential for 

significant impacts on air quality exist 

in many nonattainment areas. The 

analysis of speciated air quality data 

24284 Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 

5 Data from the PM Supersites Program 

documented in a September 2004 summary 

response entitled, ‘‘Policy Relevant Science 

Questions Regarding PM—Precursors,’’ Prepared by 

Spyros Pandis, CMU; David Allen, University of 

Texas at Austin; Armistead (Ted) Russell, Georgia 

Institute of Technology; and Paul A. Solomon, U.S. 

EPA, ORD. This document can be found in the 

docket for today’s rulemaking.

and the discussion of emission 

inventory data in the November 2003 

transportation conformity notice of 

proposed rulemaking provide an 

appropriate basis for deciding that states 

must include NOX in conformity 

determinations made before SIPs are 

submitted and emissions budgets are 

found adequate or approved, unless the 

state air agency and the EPA regional 

office find that on-road emissions of 

NOX are not a significant contributor to 

the area’s PM2.5 problem. 

EPA believes that requiring both the 

state air agency and the EPA regional 

office make an insignificance finding for 

NOX is warranted because in this 

rulemaking EPA has initially 

determined that NOX is a significant 

precursor for all PM2.5 nonattainment 

areas. Additionally, all other 

insignificance findings require both 

state air agency and EPA regional office 

action because they are made through 

either a motor vehicle emission budget 

adequacy finding or a SIP approval as 

required by § 93.109(k) of the 

conformity regulation. Therefore, based 

on the reasons stated above, EPA 

believes that it is necessary that both the 

state air agency and the EPA regional 

office make a finding that on-road 

emissions of NOX are an insignificant 

contributor to an area’s PM2.5 air quality 

problem prior to the submission of a 

SIP. A finding made by both agencies 

provides assurance that on-road 

emissions of NOX are in fact 

insignificant contributors to an area’s 

PM2.5 air quality problem and therefore 

may be omitted from conformity 

determinations prior to the submission 

of a SIP for the area. After a PM2.5 SIP 

is submitted, conformity determinations 

will be required for on-road emissions 

of NOX if the SIP includes emissions 

budgets that are found adequate or are 

approved. 

Volatile Organic Compounds. In 2003, 

EPA estimates that on-road motor 

vehicles accounted for 28 percent of 

total VOCs nationwide. Carbonaceous 

particles, which result, in part, from 

reactions involving VOCs, account for 

25–70% of constructed fine particle 

mass measured at specific Speciation 

Trends Network sites. The highest 

percentages of carbonaceous particles 

tend to be in the western United States, 

while the lowest percentages tend to be 

in the eastern United States.

Although research clearly indicates 

that VOCs can contribute to the 

formation of carbonaceous secondary 

PM2.5 compounds, the current science is 

still incomplete in its understanding of 

the fraction of particulate organic 

compounds that began as VOCs. A 

major reason for this existing deficiency 

is the varying degrees of volatility of 

organic compounds, as well as our 

inability to model collectively the 

reactivity of these different groups of 

compounds. For example, there are 

highly reactive volatile compounds with 

six or fewer carbon atoms that indirectly 

contribute to PM formation through 

reaction with oxidizing compounds 

such as the hydroxyl radical and ozone. 

There are also semi-volatile compounds 

with between seven and 24 carbon 

atoms that can exist in particle form and 

can readily be oxidized to form other 

low volatility compounds. Finally, high 

molecular weight organic compounds 

(with 25 carbon atoms or more and low 

vapor pressure) are emitted directly as 

primary organic particles and exist 

primarily in the condensed phase at 

ambient temperatures. For this reason, 

these high molecular weight organic 

compounds are generally considered to 

be primary particles and not VOCs. The 

relative importance of each of these 

groups of organic compounds in the 

formation of organic particles varies 

from area to area. In addition, the 

contribution of on-road source 

emissions to each of these three groups 

of organic compounds may also vary 

from area to area. 

Current scientific and technical 

information clearly shows that 

carbonaceous material is a significant 

fraction of total PM2.5 mass in most 

areas, and that certain aromatic VOC 

emissions such as toluene, xylene, and 

trimethyl-benzene are precursors to the 

formation of secondary PM2.5

(secondary organic aerosols). However, 

while significant progress has been 

made in understanding the role of 

gaseous organic material in the 

formation of organic PM, this 

relationship is complex and requires 

further research and technical tools to 

determine the extent of the contribution 

of specific VOC compounds to organic 

PM mass, prior to EPA being able to 

determine the extent of the contribution 

of VOCs to nonattainment problems in 

all PM2.5 areas. 

Additional research is also needed to 

determine the sources of VOC emissions 

that contribute most to PM2.5 air quality 

issues. For example, analysis of air 

quality samples collected in Pittsburgh, 

Pennsylvania from 1998 through 2003 

indicate that approximately half of the 

secondary organic aerosol in Pittsburgh 

may be attributable to biogenic sources 

(e.g., trees) as opposed to anthropogenic 

sources (i.e., man-made sources such as 

power plants and motor vehicles). 

Similarly, analysis of air quality 

samples collected in Atlanta, Georgia 

from 1998 through 2003 indicate that as 

much as 80 percent of the secondary 

organic aerosol may be attributable to 

biogenic sources. These data 5 are 

significant because biogenic emissions 

cannot be controlled. In addition, EPA 

believes that in some PM2.5

nonattainment areas, particularly during 

seasons with high photochemical 

activity, a significant amount of the 

secondary organic aerosol may be due to 

biogenic emissions as opposed to 

anthropogenic emissions of VOCs, as 

evidenced by the data from Pittsburgh 

and Atlanta.

EPA acknowledges that analytical 

tools are evolving to enable areas to 

adequately model the contribution of 

VOCs to PM2.5 formation. Researchers in 

the field anticipate that within the next 

five years the ability of models to 

simulate various components of PM2.5

will improve greatly, as will their ability 

to estimate the effectiveness of various 

control measures. These model 

improvements are particularly 

significant for secondary organic 

aerosols and biogenic and 

anthropogenic emissions of VOCs. 

However, until such model 

improvements are made and our 

understanding of VOC secondary 

particle formation improves, EPA 

believes it is not appropriate to require 

regional conformity analyses for VOCs 

in PM2.5 nonattainment areas prior to 

the submission of a PM2.5 SIP and 

emissions budgets for VOCs being found 

adequate or approved, unless the state 

air agency or EPA regional office finds 

that VOCs are a significant contributor 

to an area’s PM2.5 problem. If a state 

determines through its SIP development 

process that on-road emissions of VOCs 

are significant and the SIP includes an 

adequate or approved emissions budget 

for VOCs, then future conformity 

determinations will be required to 

include a regional emissions analysis for 

VOCs. 

Ammonia. We believe a case-by-case 

approach is also appropriate for 

ammonia because there is sufficient 

uncertainty about emissions inventories 

and about the potential efficacy of 

control measures from location to 

location. Reductions of ammonia may 

be effective primarily in areas where 

nitric acid is in abundance and 

ammonia is the limiting factor to 

ammonium nitrate formation 

(ammonium nitrate is a type of 

Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 24285

particulate matter). Although ammonia 

reductions may be appropriate in 

selected locations, in other locations 

such reductions may lead to increased 

atmospheric acidity, exacerbating acidic 

deposition problems. In other words, 

states should evaluate the benefits of 

including ammonia in conformity 

determinations prior to the submission 

of SIPs and emissions budgets being 

found adequate or approved. Therefore, 

states are not required to include 

ammonia in conformity determinations 

prior to submission of a SIP unless the 

state air agency or EPA regional office 

makes a finding that on-road emissions 

of ammonia are a significant contributor 

to an area’s PM2.5 problem. If a state 

determines through its SIP development 

process that on-road emissions of 

ammonia are significant and the SIP 

includes an adequate or approved 

emissions budget for ammonia, then 

future conformity determinations will 

be required to include a regional 

emissions analysis for ammonia.

C. Response to Comments

1. Required Precursors 

Two comments received on the 

November 5, 2003, proposed rulemaking 

indicated support for identifying NOX, 

VOCs, SOX and ammonia as potential 

transportation-related PM2.5 precursors. 

No commenters were opposed to 

identifying all of these as potential 

precursors. 

EPA received a number of comments 

on the proposed options for addressing 

precursors during the period before 

PM2.5 SIPs are submitted and emissions 

budgets are found adequate or 

approved. The majority of commenters 

supported option 2 included in the 

November 2003 proposal. Option 2 

would have required significance 

findings for any of the four precursors 

to be analyzed in conformity 

determinations prior to EPA finding 

emissions budgets in a PM2.5 SIP 

adequate or EPA’s approval of that SIP. 

Some commenters that supported 

option 2 believed that limited resources 

would be best used by determining 

which precursors contribute 

significantly to an area’s air quality 

problem before conformity for those 

precursors was required. A number of 

commenters also supported the 

proposed option 1. Option 1 would have 

required NOX and VOCs to be analyzed 

in conformity determinations prior to 

the submission of PM2.5 SIPs unless one 

or both precursors was determined to be 

insignificant. This option also would 

not have required SOX or ammonia to be 

analyzed for conformity prior to a 

submitted SIP unless one or both 

precursors was found significant. Two 

supporters of option 1 believed 

sufficient air quality data exists for their 

areas to support requiring analysis of 

NOX and VOCs in conformity 

determinations prior to the submission 

of a PM2.5 SIP. 

One commenter recommended that to 

properly implement the Clean Air Act 

in all PM2.5 areas, conformity 

determinations should be required for 

all four precursors prior to the 

submission of a PM2.5 SIP unless a 

precursor was found to be insignificant. 

This commenter believed that it would 

be unreasonable to allow an area to opt 

out of conducting an analysis by default 

for a precursor that could be responsible 

for a large portion of PM2.5. 

Additionally, two commenters indicated 

that SOX should be addressed in 

conformity determinations prior to 

submission of a PM2.5 SIP unless it is 

found to be insignificant. One 

commenter stated that ammonia should 

be included in conformity 

determinations as soon as modeling and 

analysis tools are available. Another 

commenter opined that the only 

pollutant that should require a 

significance finding prior to the 

submission of a PM2.5 SIP is ammonia. 

EPA considered all of these comments 

along with a number of other factors 

including, speciated air quality data, 

emissions inventory information, and 

the state of the scientific understanding 

of the formation of secondary particles. 

We based today’s decision on all of 

these factors as described above in 

section III.B. 

Several commenters believed that SIP 

budgets for one or more of the PM2.5

precursors should be established before 

conformity is required for those 

precursors. Specifically, two 

commenters believed that SOX and 

ammonia should be evaluated for 

significance and have SIP budgets 

before conformity is required. Three 

other commenters believed that 

conformity determinations should not 

be required for any PM2.5 precursors 

prior to the submission of a SIP and 

emissions budgets being found adequate 

or approved. One of these commenters 

stated that §§ 93.102(b)(2)(iii)–(v) and 

93.102(b)(3) should refer to budgets 

because conformity should only be 

required if there is an explicit motor 

vehicle emissions budget that is 

intended to be a ceiling on future 

emissions. 

EPA disagrees with these 

commenters. Clean Air Act section 

176(c)(6) requires that conformity apply 

in new nonattainment areas one year 

after the effective date of the 

nonattainment designation, even prior 

to the submission of SIPs establishing 

budgets for a particular pollutant or 

precursor. Clean Air Act section 

176(c)(4) provides EPA with the 

authority to establish conformity tests 

that will ensure that transportation 

plans, TIPs and projects do not result in 

new violations of an air quality 

standard, increase the frequency or 

severity of an existing violation, or 

delay timely attainment of a standard 

during the period before a SIP is 

submitted. While the contribution of 

mobile sources to PM2.5 nonattainment 

problems is likely to vary from area to 

area, on-road emissions of at least NOX, 

and perhaps other precursors, are likely 

to make a significant contribution to 

PM2.5 problems in most areas. Therefore, 

EPA believes it is both required by the 

Clean Air Act and necessary to protect 

public health for PM2.5 areas to begin 

considering the role of on-road 

emissions of PM2.5 precursors in their 

PM2.5 air quality problems, and to 

demonstrate conformity for those 

precursors that make a significant 

contribution to their air quality 

problems once conformity applies for 

PM2.5. Before adequate or approved SIP 

budgets are established, PM2.5 areas 

must use one of the interim emissions 

tests in § 93.119 to fulfill this statutory 

requirement. 

One commenter opined that requiring 

conformity for additional precursors 

results in additional burden. The 

commenter stated that any additional 

pollutant or precursor that has to be 

included in a conformity determination 

leads to additional modeling runs, 

additional documentation of results, 

additional explanation to the public and 

regional decision makers and an 

additional opportunity for a conformity 

lapse. This commenter believed that 

EPA should not minimize these 

resource requirements or use this 

argument to support the inclusion of 

PM2.5 precursors in conformity 

determinations prior to a SIP 

submission.

EPA understands the commenter’s 

concerns and has attempted to structure 

requirements for PM2.5 precursors so 

that human health and air quality are 

protected while targeting regional 

emissions analyses to only those 

precursors whose on-road emissions 

make a significant contribution to an 

area’s PM2.5 air quality problem. 

However, EPA continues to believe as 

stated in the November 2003 proposal 

that including PM2.5 precursors in PM2.5

regional emissions analyses prior to the 

submission of a SIP should not result in 

any additional transportation or 

emissions modeling because PM2.5 areas 

will already be producing VMT and 

24286 Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 

emissions estimates for direct PM2.5 (68 

FR 62706). The same VMT estimates 

would be used in calculating emissions 

of any and all precursors. Additionally, 

emission factors for the relevant 

precursors would generally be produced 

in the same model runs as the emission 

factors for direct PM2.5. EPA recognizes 

that there would be some small increase 

in burden in documenting these results 

and in discussing these precursors with 

regional decision makers and the public, 

but we believe this small increase is 

merited if a precursor is a significant 

contributor to an area’s air quality 

problem. 

EPA also recognizes that it is possible 

that an area could lapse because it may 

not be able to demonstrate conformity 

for one or more of the PM2.5 precursors. 

EPA and DOT always attempt to work 

with areas that are experiencing 

problems demonstrating conformity in 

order to resolve problems before a lapse 

occurs. However, the Clean Air Act’s 

conformity requirements are intended to 

ensure that the use of Federal 

transportation funds does not cause new 

air quality problems, make existing 

problems worse, or delay meeting a 

Clean Air Act requirement such as 

attainment. Therefore, if one or more 

precursors is a significant contributor to 

an area’s air quality problem, the 

inability to demonstrate conformity for 

such precursors would be consistent 

with the Clean Air Act’s intended 

purpose of the conformity process. In 

other words, if conformity cannot be 

demonstrated for a significant precursor, 

Federal transportation funds could not 

be spent on transportation activities that 

potentially would cause a new air 

quality problem, worsen an existing 

problem, or delay attainment or other 

emission reduction milestone. The 

inability to demonstrate conformity 

would indicate that further action is 

needed before Federal transportation 

funding and approvals can occur so that 

ultimately both transportation and air 

quality goals are achieved. 

2. Significance Findings 

A number of commenters expressed 

support for significance findings to be 

made by either the state air agency or 

the EPA regional office before a PM2.5

SIP is submitted. However, commenters 

also suggested different options for 

making significance findings. Thirteen 

commenters stated that both the state air 

agency and the EPA regional office 

should make the finding, while two 

commenters stated that the finding 

should be made through an area’s 

interagency consultation process. 

Another commenter recommended that 

only the state should have the ability to 

make significance findings. 

EPA is making one change with 

regard to insignificance findings. EPA 

has determined that insignificance 

findings for NOX should be made by 

both the state air agency and the EPA 

regional office. EPA believes that 

requiring both the state air agency and 

the EPA regional office to make an 

insignificance finding for NOX is 

appropriate because, as stated above in 

this rulemaking, EPA has initially 

determined that NOX is a significant 

precursor for all PM2.5 nonattainment 

areas. Additionally, all other 

insignificance findings made within the 

transportation conformity and SIP 

processes require both state air agency 

and EPA regional office action because 

they are made through either a motor 

vehicle emission budget adequacy 

finding or a SIP approval as required by 

§ 93.109(k) of the conformity regulation. 

Therefore, EPA believes that it is 

necessary that both the state air agency 

and the EPA regional office make a 

finding that on-road emissions of NOX

are an insignificant contributor to an 

area’s PM2.5 air quality problem prior to 

the submission of a SIP. A finding made 

by both agencies provides assurance 

that on-road emissions of NOX are in 

fact insignificant contributors to an 

area’s PM2.5 air quality problem and 

therefore may be omitted from 

conformity determinations prior to the 

submission of a SIP for the area. 

Finally, EPA believes that an 

insignificance finding for NOX should 

be made by both the state air agency and 

the EPA regional office because NOX is 

the only pollutant/precursor for which a 

regional analysis is not required if a 

finding is made. That is, the conformity 

rule allows NOX to be found 

insignificant before a SIP is submitted 

and therefore not be included in 

subsequent conformity determinations. 

For all other PM2.5 and PM10 pollutants/

precursors covered by the conformity 

rule (i.e., VOCs, SOX and ammonia as 

PM2.5 precursors; NOX and VOCs as 

PM10 precursors and road dust as a 

contributor to PM2.5 air quality 

problems) either the state air agency or 

the EPA regional office can decide if 

emissions are significant and therefore 

should be included in conformity 

determinations prior to the submission 

of a SIP and emissions budgets being 

found adequate or approved. However, 

a finding for NOX (in this case, a finding 

of insignificance) would lead to a less 

environmentally conservative result 

where NOX would no longer be 

considered in conformity 

determinations.

In contrast, consistent with the rule’s 

requirements for significance findings 

for other precursor emissions and the 

November 5, 2003, proposal, today’s 

action specifies that significance 

findings for VOCs, SOX and ammonia as 

PM2.5 precursors can be made by either 

the state air agency or the EPA regional 

office. We believe that changes to the 

procedures for finding VOCs, SOX and 

ammonia precursor emissions 

significant in response to comments are 

unnecessary because such findings 

would result in the inclusion of one or 

more precursors in conformity which 

would be more environmentally 

protective. Furthermore, allowing 

significance findings for VOCs, SOX and 

ammonia to be made by either the state 

air agency or the EPA regional office 

acknowledges the state’s authority as 

well as EPA’s role in ensuring national 

consistency in such decisions. The 

language used in the final rule for these 

three PM2.5 precursors is consistent with 

how such findings have been made for 

PM10 precursors, since the original 1993 

conformity rule. Today’s final rule for 

these three precursors is also consistent 

with how such findings are to be made 

for PM2.5 road dust. The road dust 

requirements were finalized in the July 

1, 2004, final rule. EPA believes that 

maintaining consistency in cases where 

precursors are determined to be 

significant will facilitate 

implementation of the conformity rules 

with no adverse impacts, in light of the 

role interagency consultation will play 

as explained above. 

One commenter, who favored 

including all precursors in conformity 

determinations prior to the submission 

of a SIP, stated that a precursor could 

be found to be insignificant if current 

on-road emissions are less than five 

percent of total PM2.5 and no increases 

are expected on a percentage basis 

during the period covered by the SIP or 

the conformity determination for the 

area. EPA disagrees with this suggested 

approach. Merely using a percentage 

level as a basis for a significance or 

insignificance finding ignores many 

other aspects of an area’s nonattainment 

problem. Rather, EPA believes that a 

combination of the criteria for 

insignificance findings contained in 

§ 93.109(k) of the conformity rule and 

the discussion of insignificance and 

significance findings as they apply to 

PM2.5 precursors contained in this 

notice provide the appropriate basis for 

deciding whether or not a PM2.5

precursor is significant or insignificant 

in a given area. Discussion of EPA’s 

rationale for establishing criteria for 

significance and insignificance findings 

Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 24287

can be found in the preamble to the July 

1, 2004, final rule (69 FR 40061 through 

40063). Therefore, EPA is not adopting 

the criteria suggested by the commenter. 

One commenter believed that if all 

precursors were considered in 

conformity prior to a SIP submission it 

could be presumed that these precursors 

will ultimately be included in the SIP 

for the area. In such a case, the 

commenter believed it would be 

difficult to justify not including the 

precursors in the SIP for the area if the 

state presumptively includes all of them 

in the first conformity determination. As 

previously stated, under today’s final 

rule any significance finding made prior 

to EPA’s adequacy finding for budgets 

in a SIP, or EPA’s approval of the SIP, 

should not be viewed as the ultimate 

determination of the significance of 

precursor emissions in a given area. 

State and local agencies may find 

through the SIP development process 

that emissions of one or more precursors 

are significant, even if a precursor had 

previously been considered 

insignificant. In such a case, the PM2.5

SIP would establish a motor vehicle 

emissions budget for that precursor and 

a regional emissions analysis for that 

precursor would be included in 

subsequent conformity determinations. 

Similarly, state and local agencies may 

find that a precursor is insignificant 

when preparing the SIP, even if 

previously found significant prior to the 

SIP’s preparation. 

One commenter stated that the 

insignificance policy should be applied 

to precursor emissions in PM2.5

nonattainment and maintenance areas 

for a variety of reasons such as the need 

for additional information on the nature 

and cause of an area’s PM2.5 problem, 

speciation of PM2.5 and availability of 

PM2.5 control measures. EPA agrees with 

this commenter. Today’s final rule 

allows nonattainment areas to make 

findings on the significance of each of 

the four precursors to their PM2.5 air 

quality problem during the period 

before a SIP is submitted and budgets 

are found adequate as described above. 

The insignificance policy also generally 

applies after a SIP is submitted, via the 

decisions about precursors that are 

determined in the SIP. 

One commenter requested additional 

guidance on significance and 

insignificance findings. EPA does not 

believe that additional guidance on 

significance and insignificance findings 

is necessary at this time. EPA has 

described the criteria to be considered 

and the process to be used in making 

these findings in § 93.109(k) of the 

conformity rule and in today’s 

preamble. Additional discussion and 

details on insignificance findings can be 

found in the preamble to the July 1, 

2004, final rule (69 FR 40061 through 

40063). 

3. Precursors in SIPs 

One commenter stated that after PM2.5

SIPs are submitted, areas should 

consider all four precursors in 

conformity determinations unless the 

SIP clearly states that one or more 

precursors are insignificant. EPA is not 

making any changes in response to this 

comment. EPA does not believe that it 

is necessary for a SIP to explicitly state 

that a precursor is insignificant. Instead, 

EPA believes that states will consider 

the on-road contribution of all four 

precursors to the PM2.5 problem as they 

develop their SIPs. If through the SIP 

process a state concludes that on-road 

emissions of one or more precursors 

needs to be addressed in order to attain 

the PM2.5 standard as expeditiously as 

practicable, then EPA expects that the 

state will include an emissions budget 

in the SIP for each of the relevant 

precursors. A conformity determination 

will then be required for each precursor 

for which there is a budget, after the 

emissions budgets are found adequate or 

approved. In making a decision about 

each precursor, states should consider 

the insignificance criteria contained in 

§ 93.109(k) of the conformity rule and 

the current state of the science 

concerning the precursor’s role in the 

formation of PM2.5. Once SIPs are 

submitted and found adequate or 

approved the conformity rule requires 

that conformity be assessed against the 

budgets in the applicable SIP. 

Conformity determinations must then 

address all precursors for which the SIP 

establishes a budget, and need not 

address any possible precursor for 

which the state has not established a 

budget because the emissions of that 

precursor are insignificant.

EPA notes that, if inventory and 

modeling analyses demonstrating 

reasonable further progress, attainment 

or maintenance indicate a level of 

emissions of a precursor that must be 

maintained to demonstrate compliance 

with the applicable requirement, then 

that level of emissions should be clearly 

identified in the SIP as a motor vehicle 

emissions budget for transportation 

conformity purposes consistent with 

§ 93.118(e) even if the SIP does not 

establish particular controls for the 

given precursor. If the state fails to 

identify such a level of emissions as a 

motor vehicle emissions budget, EPA 

will find the submitted SIP budgets 

inadequate because the SIP fails to 

clearly identify the motor vehicle 

emissions budget as required by 

conformity rule § 93.118(e)(4)(iii). 

Several commenters raised concerns 

about SIP development and regional 

emissions analyses in areas that are 

nonattainment for both 8-hour ozone 

and PM2.5. One of these commenters 

asked if NOX and VOC conformity 

analyses would be the same for both 

pollutants in these areas. Another 

commenter asked if NOX and VOC 

budgets would be the same for 8-hour 

ozone and PM2.5 SIPs in these areas. 

EPA does not expect that either 

regional emissions analyses or budgets 

for NOX and VOCs will be the same for 

8-hour ozone and PM2.5 standards in 

areas that are nonattainment for both 

pollutants, for several reasons. First, it 

is likely that most areas will have 

different attainment dates for each of the 

two pollutants, which means that it is 

likely that analyses and budgets will be 

required for different years. Second, it is 

possible that in many cases the 

boundaries of the nonattainment area 

for each pollutant may be different. For 

example, the 8-hour ozone 

nonattainment area may contain more 

counties than the PM2.5 nonattainment 

area or vice versa. Finally, VOC and 

NOX regional emissions analyses and 

budgets for 8-hour ozone and PM2.5

areas will most likely be developed 

using different meteorological 

conditions and, in some areas, different 

travel patterns. For example, because in 

most areas, ozone is a summertime 

pollutant, NOX and VOC regional 

emissions and budgets in 8-hour ozone 

areas would be calculated using 

meteorological and travel data for a 

‘‘typical’’ summer day. In contrast, NOX

and VOC regional emissions and 

budgets for PM2.5 areas may be 

established using annual averages for 

meteorological and traffic conditions, 

rather than conditions for only a 

particular season, because most PM2.5

nonattainment areas are violating the 

annual PM2.5 standard instead of the 24-

hour standard. 

One commenter stated that there was 

an error in the proposed option 1 

language in § 93.102(b)(iv) of the 

November 2003 rulemaking. 

Specifically, the commenter suggested 

that the proposed language appeared to 

require conformity determinations for 

NOX and VOCs if a submitted SIP does 

not contain emissions budgets for NOX

and VOCs. EPA disagrees; the language 

as proposed for NOX and VOCs is 

correct and we are retaining that 

language for NOX in today’s final rule. 

We believe that the commenter 

misunderstood the proposal. The 

language in § 93.102(b)(iv) that is 

finalized today requires that conformity 

24288 Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 

6USEPA, 2003. Air Quality Criteria for 

Particulate Matter (Fourth External Review Draft). 

EPA/600/P–99/002aD and bD. U.S. Environmental 

Protection Agency, Office of Research and 

Development, National Center For Environmental 

Assessment, Research Triangle Park Office, 

Research Triangle Park, NC. June 2003. Available 

electronically at http://cfpub.epa.gov/ncea/cfm/

partmatt.cfm.

7North American Research Strategy for 

Tropospheric Ozone (NARSTO) and Particulate 

Matter, Particulate Matter Science for Policy 

Makers—A NARSTO Assessment, Parts 1 and 2. 

NARSTO Management Office (Envair), Pasco, 

Washington. February 2003.

determinations be made for NOX unless: 

(1) During the period before a SIP is 

submitted and budgets are found 

adequate or approved the state air 

agency and EPA regional office make a 

finding that on-road emissions of NOX

are not significant contributors to an 

area’s air quality problem; and/or (2) the 

area’s SIP does not establish an 

emissions budget for on-road emissions 

of NOX. In other words, if the SIP 

includes an adequate or approved 

emissions budget for NOX, then NOX

must be analyzed in conformity 

determinations in PM2.5 nonattainment 

areas. In contrast, if the SIP does not 

contain a budget for NOX and instead 

concludes that emissions of NOX could 

rise to any reasonably foreseeable level 

without impairing reasonable further 

progress or attainment, EPA would 

make an insignificance finding, either 

through a motor vehicle emissions 

budget adequacy finding or through a 

SIP approval, and NOX would not have 

to be considered for conformity 

purposes. 

4. Modeling Concerns 

Several commenters expressed 

concerns about generating estimates for 

PM2.5 precursors. One commenter stated 

that few areas have experience using 

MOBILE6 to evaluate PM2.5 emissions 

and that unexpected issues and 

problems will arise from the use of 

MOBILE6. The commenter believed that 

difficulties will come from both model 

shortcomings and inexperience of the 

users. Another commenter had concerns 

about relying on a future release of 

MOBILE6.2 or other future guidance for 

estimating precursor emissions. A third 

commenter stated that there is a need 

for guidance on analysis techniques for 

ammonia and SOX. 

Since the conformity proposal was 

published in November 2003, EPA has 

released MOBILE6.2. MOBILE6.2 is 

based on the latest available information 

concerning vehicle emissions and is 

therefore the best available tool at this 

time for calculating on-road emissions 

of PM2.5 precursors (in all states except 

California). The Federal Register notice 

announcing the release of the model 

was published on May 19, 2004 (69 FR 

28830). EPA released SIP and 

conformity policy guidance on the use 

of MOBILE6.2 on February 24, 2004, 

entitled, ‘‘Policy Guidance on the Use of 

MOBILE6.2 and the December 2003 AP–

42 Method for Re-Entrained Road Dust 

for SIP Development and Transportation 

Conformity.’’ EPA released technical 

guidance on the use of the MOBILE6.2 

model in August 2004. Information on 

training in the use of MOBILE6.2, 

related policy memoranda and the 

technical guidance in the use of the 

model are available on EPA’s MOBILE 

Web site at http://www.epa.gov/otaq/

m6.htm.

EPA understands the concerns that 

these commenters have expressed about 

estimating precursors. However, we 

believe there is adequate time for new 

areas to gain MOBILE experience and 

conduct conformity analyses for the 

PM2.5 standard before the end of the 

one-year conformity grace period. We 

believe that the material described 

above contains sufficient information 

for the states that use MOBILE to 

conduct modeling of on-road emissions 

of ammonia and SOX. Therefore, we 

believe that additional guidance or 

analytical techniques for estimating 

these precursors is unnecessary. EPA 

recognizes, however, that California 

needs to complete the development of a 

methodology for estimating on-road 

emissions of ammonia before ammonia 

would be included in conformity 

determinations in California, as 

discussed above in Section III. A. 

5. State of the Science 

Two commenters expressed concern 

about the current understanding of the 

formation of secondary particles. One 

commenter stated that the role of 

ammonia needs to be evaluated quickly 

so that states can have all information 

possible while they plan to attain the 

PM2.5 standard. The other commenter 

stated that there is a lack of 

understanding about the formation of 

secondary particles. This commenter 

believed that unnecessary analysis of 

potential PM2.5 precursors would be 

time consuming and overly burdensome 

without producing substantial air 

quality benefits.

EPA acknowledges that our 

understanding of the formation of 

secondary particles is not complete. 

However, EPA believes that this final 

rule strikes an appropriate balance 

between preserving limited state and 

local resources and environmental 

protection. Our incomplete 

understanding of the role of VOCs and 

ammonia in the formation of secondary 

particles is one of the reasons that we 

determined that PM2.5 nonattainment 

areas should not be required to address 

those precursors in conformity 

determinations before SIP budgets are 

available unless a significance finding is 

made. On the other hand, EPA believes 

that there is clear evidence and a 

substantial understanding of the role of 

NOX and SOX in the formation of 

secondary particles. Additional 

information on the role of each of the 

precursors can be found in the U.S. EPA 

Criteria Document,6 and in the NARSTO 

Fine Particle Assessment.7

EPA agrees that further research is 

needed on the role of ammonia in 

particle formation and the benefits of 

ammonia control measures. Ongoing 

research is expected to greatly improve 

our understanding of ammonia control 

measures as well as our understanding 

of the role of ammonia in aerosol 

formation. However, as states and EPA 

develop a greater understanding over 

the coming years about the air quality 

effects of reducing ammonia emissions 

in specific nonattainment areas, it may 

be appropriate for ammonia reduction 

strategies to be included in future SIPs 

and it may be appropriate to include 

ammonia in future conformity 

determinations. 

6. Comment Period 

One commenter requested an 

additional comment period for PM2.5

related requirements. As stated in the 

July 1, 2004, Federal Register notice, 

EPA determined that it is not necessary 

to reopen the comment period on the 

proposed options for addressing PM2.5

precursors in conformity determinations 

(69 FR 40032). EPA published a 

supplemental proposal on PM2.5 hotspot analyses on December 13, 2004. 

Providing the public with an 

opportunity to comment the proposed 

options for hot-spot analyses. 

Additionally, when EPA publishes the 

proposed PM2.5 implementation strategy 

the public will have the opportunity to 

comment on that proposal as well. EPA 

concludes that the comment periods for 

these rulemakings has provided the 

public with adequate time to comment 

on additional issues related to PM2.5. 

IV. Technical Correction to Public 

Consultation Procedures 

In this action, we are correcting a 

cross-reference to a provision of DOT’s 

transportation planning regulations that 

is cited under the public consultation 

procedure requirements in § 93.105(e) of 

the conformity rule. This cross-reference 

to the transportation planning 

regulations is intended to specify the 

provision of DOT’s regulations that 

Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 24289

contains the fee schedule for public 

inspection and copying of 

transportation planning and conformity 

documents. Prior to today’s action the 

cross-reference was listed as 49 CFR 

7.95; this final rule changes the crossreference to 49 CFR 7.43. 

EPA is making this technical 

correction to § 93.105(e) as a result of 

DOT’s July 16, 1998, final rule that 

changed the citation of the 

transportation planning fee schedule 

provision (63 FR 38331). We did not 

issue a proposal or provide an 

opportunity for public comment for this 

minor correction to the rule. We believe 

such actions are unnecessary because 

this minor revision in no way changes 

the substantive public consultation 

procedures described in § 93.105(e) of 

the conformity rule. This revision 

merely updates a cross reference in the 

conformity rule to be consistent with 

the recodification of DOT’s regulations 

so that implementers can more easily 

locate the correct corresponding DOT 

regulation. 

V. How Does Today’s Final Rule Affect 

Conformity SIPs? 

Today’s final rule does not affect 

conformity SIP requirements. In all 

nonattainment and maintenance areas 

with and without approved conformity 

SIPs, the final rule requirements for 

PM2.5 precursors will apply immediately 

upon the effective date of today’s action 

because no prior conformity rules (or 

approved conformity SIPs) address 

precursors for PM2.5. The technical 

correction to § 93.105(e) included in this 

rulemaking will apply immediately 

upon the effective date in all areas 

except those that have an approved 

conformity SIP containing this 

provision. For these areas, the 

§ 93.105(e) correction will not be 

reflected in their SIPs until the state 

includes the correction in a SIP revision 

and EPA approves that revision. EPA 

has no authority to disregard this 

statutory requirement for this portion of 

today’s final rule. EPA does not believe, 

however, that the conformity SIP 

requirement will preclude areas with 

approved SIPs from appropriately 

implementing § 93.105(e), as today’s 

action merely corrects a cross-reference 

to DOT’s transportation planning 

regulations. We believe that areas can 

interpret their approved conformity SIPs 

consistent with today’s change to reflect 

the new correct citation. We believe this 

interpretation would be reasonable, 

given that this change to DOT’s fee 

schedule rules is merely one of 

reorganizing and not one of substance. 

EPA will work with states as 

appropriate to approve revisions to their 

conformity SIPs as expeditiously as 

possible through flexible administrative 

techniques such as parallel processing 

and direct final rulemaking. EPA 

released guidance on conformity SIPs 

on November 18, 2004, entitled, 

‘‘Conformity SIP Guidance.’’ This 

guidance is primarily intended to assist 

areas with approved conformity SIPs 

determine which provisions of the July 

1, 2004, conformity rule amendments 

apply immediately and which 

provisions cannot apply until their 

conformity SIPs are revised. 

By way of background, Clean Air Act 

section 176(c)(4)(C) currently requires 

states to submit revisions to their SIPs 

to reflect the criteria and procedures for 

determining conformity. States can 

choose to develop conformity SIPs as a 

memorandum of understanding (MOU), 

memorandum of agreement (MOA), or 

state rule. However, a state must have 

and use its authority to make an MOU 

or MOA enforceable as a matter of state 

law, if such mechanisms are used. 

Section 51.390(b) of the conformity rule 

specifies that after EPA approves a 

conformity SIP revision, the federal 

conformity rule no longer governs 

conformity determinations (for the parts 

of the rule that are covered by the 

approved conformity SIP). In 

accordance with § 51.390, states must 

submit a revision to their conformity 

SIP to reflect the provisions of this final 

rule within 12 months of the 

publication date. 

VI. Statutory and Executive Order 

Reviews 

A. Executive Order 12866: Regulatory 

Planning and Review

Under Executive Order 12866, (58 FR 

51735; October 4, 1993) the Agency 

must determine whether the regulatory 

action is ‘‘significant’’ and therefore 

subject to OMB review and the 

requirements of the Executive Order. 

The Order defines ‘‘significant 

regulatory action’’ as one that is likely 

to result in a rule that may: 

(1) Have an annual effect on the 

economy of $100 million or more, or 

otherwise adversely affect in a material 

way the economy; a sector of the 

economy; productivity; competition; 

jobs; the environment; public health or 

safety; or State, local, or tribal 

governments or communities; 

(2) Create a serious inconsistency or 

otherwise interfere with an action taken 

or planned by another agency; 

(3) Materially alter the budgetary 

impact of entitlements, grants, user fees, 

or loan programs or the rights and 

obligations of recipients thereof; 

(4) Raise novel legal or policy issues 

arising out of legal mandates, the 

President’s priorities, or the principles 

set forth in the Executive Order. 

It has been determined that this final 

rule is not a ‘‘significant regulatory 

action’’ under the terms of Executive 

Order and therefore not subject to OMB. 

B. Paperwork Reduction Act 

The Office of Management and Budget 

(OMB) has approved the information 

collection requirements contained in 

this rule under the provisions of the 

Paperwork Reduction Act, 44 U.S.C. 

3501 et seq. And has assigned OMB 

control number 2060–0561. 

Transportation conformity 

determinations are required under Clean 

Air Act section 176(c) (42 U.S.C. 

7506(c)) to ensure that federally 

supported highway and transit project 

activities are consistent with (‘‘conform 

to’’) the purpose of the SIP. Conformity 

to the purpose of the SIP means that 

transportation activities will not cause 

or contribute to new air quality 

violations, worsen existing violations, or 

delay timely attainment of the relevant 

air quality standards. Transportation 

conformity applies under EPA’s 

conformity regulations at 40 CFR parts 

51.390 and 93 to areas that are 

designated nonattainment and those 

redesignated to attainment after 1990 

(‘‘maintenance areas’’ with SIPs 

developed under Clean Air Act section 

175A) for transportation-source criteria 

pollutants. The Clean Air Act gives EPA 

the statutory authority to establish the 

criteria and procedures for determining 

whether transportation activities 

conform to the SIP. 

EPA provided two opportunities for 

public comment on the incremental 

burden estimates for transportation 

conformity determinations under the 

new 8-hour ozone and PM2.5 standards. 

EPA received comments on both the 

initial burden estimates provided in the 

November 5, 2003, proposal (68 FR 

62720) and on the revised estimates in 

the January 5, 2004, ICR (69 FR 336). 

EPA responded to all of these comments 

in the ICR that has been approved by 

OMB. This ICR addresses all aspects of 

the conformity rulemaking effort for the 

new air quality standards. EPA 

estimated burden in this ICR is based on 

implementing the most intensive 

options proposed for all aspects of the 

conformity rules, including PM2.5

precursors. The options selected in 

today’s final action are consistent with 

the burden estimated in the ICR. 

Burden means the total time, effort, or 

financial resources expended by persons 

to generate, maintain, retain, or disclose 

or provide information to or for a federal 

24290 Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 

agency. This includes the time needed 

to review instructions; develop, acquire, 

install and utilize technology and 

systems for the purposes of collecting, 

validating, and verifying information; 

process and maintain information; and 

disclose and provide information; adjust 

the existing ways to comply with any 

previously applicable instructions and 

requirements; train personnel to be able 

to respond to a collection of 

information; search data sources; 

complete and review the collection of 

information; and, transmit or otherwise 

disclose the information.

An agency may not conduct or 

sponsor, and a person is not required to 

respond to a collection of information 

unless it displays a currently valid OMB 

control number. The OMB control 

numbers for EPA’s regulations in 40 

CFR are listed in 40 CFR part 9. In 

addition, EPA has amended the table in 

40 CFR part 9 of currently approved 

OMB control numbers for various 

regulations to list the regulatory 

citations for the information 

requirements contained in this final 

rule. 

C. Regulatory Flexibility Act 

The Regulatory Flexibility Act, as 

amended by the Small Business 

Regulatory Enforcement Fairness Act of 

1996, requires the Agency to prepare a 

regulatory flexibility analysis of any rule 

subject to notice and comment 

rulemaking requirements under the 

Administrative Procedure Act or any 

other statute unless the agency certifies 

that the rule will not have a significant 

economic impact on a substantial 

number of small entities. Small entities 

include small businesses, small not-forprofit organizations and small 

governmental jurisdictions. 

For purposes of assessing the impacts 

of today’s final rule on small entities, 

small entity is defined as: (1) A small 

business as defined by the Small 

Business Administration’s (SBA) 

regulations at 13 CFR 121.201; (2) a 

small governmental jurisdiction that is a 

government of a city, county, town, 

school district or special district with a 

population of less than 50,000; and (3) 

a small organization that is any not-forprofit enterprise that is independently 

owned and operated and is not 

dominant in its field. 

After considering the economic 

impacts of today’s final rule on small 

entities, I certify that this action will not 

have a significant economic impact on 

a substantial number of small entities. 

This regulation directly affects Federal 

agencies, state departments of 

transportation and metropolitan 

planning organizations that, by 

definition, are designated under Federal 

transportation laws only for 

metropolitan areas with a population of 

at least 50,000. These organizations do 

not constitute small entities within the 

meaning of the Regulatory Flexibility 

Act. 

D. Unfunded Mandates Reform Act 

Title II of the Unfunded Mandates 

Reform Act of 1995 (UMRA), Public 

Law 104–4, establishes requirements for 

Federal agencies to assess the effects of 

their regulatory actions on State, local, 

and tribal governments and the private 

sector. Under section 202 of the UMRA, 

EPA generally must prepare a written 

statement, including a cost-benefit 

analysis, for proposed and final rules 

with ‘‘federal mandates’’ that may result 

in expenditures to State, local, and 

tribal governments, in the aggregate, or 

to the private sector, of $100 million or 

more in any one year. Before 

promulgating an EPA rule for which a 

written statement is needed, section 205 

of the UMRA generally requires EPA to 

identify and consider a reasonable 

number of regulatory alternatives and 

adopt the least costly, most costeffective or least burdensome alternative 

that achieves the objectives of the rule. 

The provisions of section 205 do not 

apply when they are inconsistent with 

applicable law. Moreover, section 205 

allows EPA to adopt an alternative other 

than the least costly, most cost-effective 

or least burdensome alternative if the 

Administrator publishes with the final 

rule an explanation why that alternative 

was not adopted. Before EPA establishes 

any regulatory requirements that may 

significantly or uniquely affect small 

governments, including tribal 

governments, it must have developed 

under section 203 of the UMRA a small 

government agency plan. The plan must 

provide for notifying potentially 

affected small governments, enabling 

officials of affected small governments 

to have meaningful and timely input in 

the development of EPA regulatory 

proposals with significant Federal 

intergovernmental mandates, and 

informing, educating, and advising 

small governments on compliance with 

the regulatory requirements. 

EPA has determined that this final 

rule itself does not contain a Federal 

mandate that may result in expenditures 

of $100 million or more for State, local, 

and tribal governments, in the aggregate, 

or the private sector in any one year. 

The primary purpose of this rulemaking 

is to incorporate into the conformity 

regulations the PM2.5 precursors that 

must be considered in conformity 

determinations in PM2.5 nonattainment 

and maintenance areas. Clean Air Act 

section 176(c)(5) requires the 

applicability of conformity to such areas 

as a matter of law one year after 

nonattainment designations. Therefore, 

this final rule merely implements 

already established law that imposes 

conformity requirements and does not 

itself impose requirements that may 

result in expenditures of $100 million or 

more in any year. As a result, today’s 

action is not subject to the requirements 

of sections 202 and 205 of the UMRA 

and EPA has not prepared a statement 

with respect to budgetary impacts. 

E. Executive Order 13132: Federalism 

Executive Order 13132, entitled 

‘‘Federalism’’ (64 FR 43255, August 10, 

1999), requires EPA to develop an 

accountable process to ensure 

‘‘meaningful and timely input by state 

and local officials in the development of 

regulatory policies that have federalism 

implications.’’ ‘‘Policies that have 

federalism implications’’ is defined in 

the Executive Order to include 

regulations that 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.’’

This final rule does not have 

federalism implications. It will 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. The Clean Air 

Act requires conformity to apply in 

certain nonattainment and maintenance 

areas as a matter of law, and this final 

rule merely establishes and revises 

procedures for transportation planning 

entities in subject areas to follow in 

meeting their existing statutory 

obligations. Thus, Executive Order 

13132 does not apply to this rule. 

F. Executive Order 13175: Consultation 

and Coordination With Indian Tribal 

Governments 

Executive Order 13175: ‘‘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 

Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 24291

the distribution of power and 

responsibilities between the Federal 

Government and Indian tribes.’’

Today’s amendments to the 

conformity rule do not significantly or 

uniquely affect the communities of 

Indian tribal governments, as the Clean 

Air Act already requires transportation 

conformity to apply as a matter of law 

in any area that is designated 

nonattainment or maintenance. This 

final rule incorporates into the 

conformity rule provisions addressing 

newly designated PM2.5 nonattainment 

and maintenance areas subject to 

conformity requirements as a matter of 

law under the Act that would not 

themselves have substantial direct 

effects on tribal governments, on the 

relationship between the Federal 

Government and Indian tribes, or on the 

distribution of power and 

responsibilities between the Federal 

Government and Indian tribes, as 

specified in Executive Order 13175. 

Accordingly, the requirements of 

Executive Order 13175 are not 

applicable to this final rule. 

G. Executive Order 13045: Protection of 

Children From Environmental Health 

and Safety Risks 

Executive Order 13045: ‘‘Protection of 

Children from Environmental Health 

Risks and Safety Risks’’ (62 FR 19885, 

April 23, 1997), applies to any rule that: 

(1) Is determined to be ‘‘economically 

significant’’ as defined under Executive 

Order 12866, and (2) concerns an 

environmental health or safety risk that 

EPA has reason to believe may have a 

disproportionate effect on children. If 

the regulatory action meets both criteria, 

the Agency must evaluate the 

environmental health or safety effects of 

the planned rule on children, and 

explain why the planned regulation is 

preferable to other potentially effective 

and reasonably feasible alternatives 

considered by the Agency. 

This final rule is not subject to 

Executive Order 13045 because it is not 

economically significant within the 

meaning of Executive Order 12866 and 

does not involve the consideration of 

relative environmental health or safety 

risks on children. 

H. Executive Order 13211: Actions That 

Significantly Affect Energy Supply, 

Distribution or Use 

This final rule is not subject to 

Executive Order 13211, ‘‘Action 

Concerning Regulations That 

Significantly Affect Energy Supply, 

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

22, 2001), because it will not have a 

significant adverse effect on the supply, 

distribution, or use of energy. 

I. National Technology Transfer and 

Advancement Act 

Section 12(d) of the National 

Technology Transfer and Advancement 

Act of 1995 (‘‘NTTAA’’), Public Law 

104–113, section 12(d) (15 U.S.C. 272 

note) directs EPA to use voluntary 

consensus standards in its regulatory 

activities unless to do so would be 

inconsistent with applicable law or 

otherwise impractical. ‘‘Voluntary 

consensus standards’’ are technical 

standards (e.g., materials specifications, 

test methods, sampling procedures, and 

business practices) that are developed or 

adopted by voluntary consensus 

standards bodies. The NTTAA directs 

EPA to provide Congress, through OMB, 

explanations when the Agency decides 

not to use available and applicable 

voluntary consensus standards. 

This rulemaking does not involve 

technical standards. Therefore, the use 

of voluntary consensus standards does 

not apply to this final rule. 

J. Congressional Review Act 

The Congressional Review Act, 5 

U.S.C. 801 et seq., as added by the Small 

Business Regulatory Enforcement 

Fairness Act of 1996, generally provides 

that before a rule may take effect, the 

agency promulgating the rule must 

submit a rule report, which includes a 

copy of the rule, to each House of the 

Congress and to the Comptroller General 

of the United States. The EPA will 

submit this final rule and other required 

information to the U.S. Senate, the U.S. 

House of Representatives, and the 

Comptroller General of the United 

States prior to publication of the final 

rule in the Federal Register. This rule 

is not a ‘‘major rule’’ as defined by 5 

U.S.C. 804(2). This rule will be effective 

on June 6, 2005. 

K. Petitions for Judicial Review 

Under section 307(b)(1) of the Clean 

Air Act, petitions for judicial review of 

this action must be filed in the United 

States Court of Appeals for the 

appropriate circuit by July 5, 2005. 

Filing a petition for reconsideration by 

the Administrator of this final rule does 

not affect the finality of this rule for the 

purposes of judicial review, nor does it 

extend the time within which a petition 

for judicial review may be filed, and 

shall not postpone the effectiveness of 

such a rule or action. This action may 

not be challenged later in proceeding to 

enforce its requirements. (See section 

307(b)(2) of the Administrative 

Procedures Act.)

List of Subjects in 40 CFR Part 93 

Environmental protection, 

Administrative practice and procedure, 

Air pollution control, Intergovernmental 

relations, Nitrogen dioxide, Particulate 

matter, Transportation, Volatile organic 

compounds.

Dated: May 2, 2005. 

Stephen L. Johnson, 

Administrator.

■ For the reasons set out in the preamble, 

40 CFR part 93 is amended as follows:

PART 93—[AMENDED]

■ 1. The authority citation for part 93 

continues to read as follows:

Authority: 42 U.S.C. 7401–7671q.

■ 2. Section 93.102 is amended by:

■ a. removing the word ‘‘and’’ at the end 

of paragraph (b)(2)(ii);

■ b. removing the period at the end of 

paragraph (b)(2)(iii) and replacing it with 

a semicolon; and

■ c. adding paragraphs (b)(2)(iv) and (v).

The revisions and additions read as 

follows:

§ 93.102 Applicability.

* * * * *

(b) * * * 

(2) * * * 

(iv) NOX in PM2.5 areas, unless both 

the EPA Regional Administrator and the 

director of the state air agency have 

made a finding that transportationrelated emissions of NOX within the 

nonattainment area are not a significant 

contributor to the PM2.5 nonattainment 

problem and has so notified the MPO 

and DOT, or the applicable 

implementation plan (or 

implementation plan submission) does 

not establish an approved (or adequate) 

budget for such emissions as part of the 

reasonable further progress, attainment 

or maintenance strategy; and 

(v) VOC, sulfur oxides (SOX) and/or 

ammonia (NH3) in PM2.5 areas either if 

the EPA Regional Administrator or the 

director of the state air agency has made 

a finding that transportation-related 

emissions of any of these precursors 

within the nonattainment area are a 

significant contributor to the PM2.5

nonattainment problem and has so 

notified the MPO and DOT, or if the 

applicable implementation plan (or 

implementation plan submission) 

establishes an approved (or adequate) 

budget for such emissions as part of the 

reasonable further progress, attainment 

or maintenance strategy.

* * * * *

■ 3. Section 93.105(e) is amended by 

revising the reference ‘‘49 CFR 7.95’’ to 

read ‘‘49 CFR 7.43.’’

■ 4. Section 93.119 is amended by:

■ a. removing the word ‘‘and’’ at the end 

of paragraph (f)(7);

24292 Federal Register / Vol. 70, No. 87 / Friday, May 6, 2005 / Rules and Regulations 

■ b. removing the period at the end of 

paragraph (f)(8) and replacing it with a 

semicolon; and

■ c. adding new paragraphs (f)(9) and 

(f)(10). 

The revisions and additions read as 

follows:

§ 93.119 Criteria and procedures: Interim 

emissions in areas without motor vehicle 

emissions budgets.

* * * * *

(f) * * * 

(9) NOX in PM2.5 areas, unless the 

EPA Regional Administrator and the 

director of the State air agency have 

made a finding that emissions of NOX

from within the area are not a 

significant contributor to the PM2.5

nonattainment problem and has so 

notified the MPO and DOT; and 

(10) VOC, SOX and/or ammonia in 

PM2.5 areas if the EPA Regional 

Administrator or the director of the 

State air agency has made a finding that 

any of such precursor emissions from 

within the area are a significant 

contributor to the PM2.5 nonattainment 

problem and has so notified the MPO 

and DOT.

* * * * *

[FR Doc. 05–9086 Filed 5–5–05; 8:45 am] 

BILLING CODE 6560–50–P