Control of Air Pollution from New Motor Vehicles: Proposed Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control Requirements

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 80, 85 and 86

[AMS-FRL-6369-5]

RIN 2060-A123

Control of Air Pollution from New Motor Vehicles: Proposed Tier 2

Motor Vehicle Emissions Standards and Gasoline Sulfur Control

Requirements

AGENCY: Environmental Protection Agency (EPA).

ACTION: Clarification of Proposed Rule, Provision of Supplemental

Information and Request for Comment.

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SUMMARY: EPA published a Notice of Proposed Rulemaking (NPRM) on May

13, 1999, proposing a major program designed to significantly reduce

the emissions from new passenger cars and light trucks, including

pickup trucks, minivans, and sport-utility vehicles (the ``Tier 2

program''). This program would provide for cleaner air by significantly

reducing vehicle emissions that contribute to increased ambient levels

of ozone and particulate matter (PM), as well as other types of

pollution. The proposed program combines requirements for cleaner

vehicles and requirements for lower levels of sulfur in gasoline. On

May 14, 1999, a panel of the Court of Appeals for the District of

Columbia Circuit ruled, among other things, that the recently-

promulgated national ambient air quality standards (NAAQS) for ozone

and PM represented unconstitutional delegations of authority, and

remanded the record to EPA for further consideration. This document

clarifies that the decision of the panel does not change EPA's proposed

requirements for a Tier 2 program and does not impact EPA's proposed

determination that the Tier 2 program is a necessary and appropriate

regulatory program that would provide cleaner air and greater public

health protection. This document also provides additional ozone

modeling information that was not included in the Notice of Proposed

Rulemaking. EPA welcomes comment on this document.

DATES: Comments: We must receive your comments on the May 13, 1999 NPRM

and on this document by August 2, 1999.

ADDRESSES: Comments: You may send written comments in paper form or by

E-mail. Send paper copies of written comments (in duplicate if

possible) to Public Docket No. A-97-10 at the following address: U.S.

Environmental Protection Agency (EPA), Air Docket (6102), Room M-1500,

401 M Street, S.W., Washington, D.C. 20460. If possible, we also

encourage you to send an electronic copy of your comments (in ASCII

format) to the docket by e-mail to A-and-R-D[email protected] or on a 3.5

inch diskette accompanying your paper copy. If you wish, you may send

your comments by E-mail to the docket at the address listed above

without the submission of a paper copy, but a paper copy will ensure

the clarity of your comments.

Please also send a separate paper copy to the contact person listed

below. If you send comments by E-mail alone, we ask that you send a

copy of the E-mail message that contains the comments to the contact

person listed below.

EPA's Air Docket is open from 8:00 a.m. to 5:30 p.m., Monday

through Friday, except on government holidays. You can reach the Air

Docket by telephone at (202) 260-7548 and by facsimile at (202) 260-

4400. We may charge a reasonable fee for copying docket materials, as

provided in 40 CFR Part 2.

FOR FURTHER INFORMATION CONTACT: Carol Connell, U.S. EPA, National

Vehicle and Fuels Emission Laboratory, 2000 Traverwood, Ann Arbor, MI

48105; Telephone (734) 214-4349, FAX (734) 214-4816, E-mail

[email protected].

SUPPLEMENTARY INFORMATION:

I. Introduction

A. Tier 2 Proposal

On May 13, 1999, EPA published in the Federal Register its proposal

to reduce emissions from light-duty vehicles (LDVs) and light-duty

trucks (LDTs). 64 FR 26004. The proposal would also significantly

reduce sulfur content in gasoline. The proposed program would phase in

beginning in 2004. The program is projected to result in reductions of

approximately 800,000 tons of nitrogen oxides (NOX) per year

by 2007 and 1,200,000 tons by 2010. It would eventually result in

reductions of about 70 percent in emissions of NOX from LDVs

and LDTs nationwide by 2020. In addition, the proposed program would

reduce the contribution of vehicles to other serious health and

environmental problems, including particulate matter, visibility

problems, toxic air pollutants, acid rain, and nitrogen loading of

estuaries.

EPA proposed the standards for LDVs and LDTs pursuant to its

authority under section 202 of the Clean Air Act (CAA or the Act). In

particular, section 202(i) of the Act provides specific procedures that

EPA must follow to determine whether Tier 2 standards for

[[Page 35113]]

LDVs and certain LDTs 1 are appropriate beginning in the

2004 model year. Specifically, we are required to first issue a study

regarding ``whether or not further reductions in emissions from light-

duty vehicles and light-duty trucks should be required'' (the ``Tier 2

study''). This study ``shall examine the need for further reductions in

emissions in order to attain or maintain the national ambient air

quality standards.'' It is also to consider (1) The availability of

technology to meet more stringent standards, taking cost, lead time,

safety, and energy impacts into consideration, and, (2) the need for,

and cost effectiveness of, such standards, including consideration of

alternative methods of attaining or maintaining the national ambient

air quality standards. EPA must then submit the study as a Report to

Congress. EPA submitted its Report to Congress on July 31, 1998.

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\1\ LDTs with a loaded vehicle weight less than or equal to 3750

pounds.

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Following the Report to Congress, EPA is required to determine by

rulemaking whether: (1) There is a need for further emission

reductions; (2) the technology for more stringent emission standards

from the affected classes will be available; and (3) such standards are

needed and cost-effective, taking into account alternatives. If EPA

makes affirmative determinations, then the Agency is to promulgate new,

more stringent motor vehicle standards (``Tier 2 standards''). EPA

proposed affirmative responses to the three questions above and

proposed new standards. EPA also proposed standards for larger light-

duty trucks (up to 8500 pounds GVWR) under the general authority of

Section 202(a)(1) and under Section 202(a)(3) of the Act, which

requires that standards applicable to emissions of hydrocarbons,

NOX, CO and PM from heavy-duty vehicles 2 reflect

the greatest degree of emission reduction available for the model year

to which such standards apply, giving appropriate consideration to

cost, energy, and safety.

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\2\ LDTs that have gross vehicle weight ratings above 6000

pounds are considered heavy-duty vehicles under the Act. See section

202(b)(3). For regulatory purposes, we refer to these LDTs as

``heavy light-duty trucks,'' made up of LDT3s and LDT4s.

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EPA proposed its gasoline sulfur controls pursuant to our authority

under section 211(c)(1) of the Clean Air Act. Under section 211(c)(1),

EPA may adopt a fuel control if at least one of the following two

criteria is met: (1) The emission products of the fuel cause or

contribute to air pollution which may reasonably be anticipated to

endanger public health or welfare, or (2) the emission products of the

fuel will significantly impair emissions control systems in general use

or which would be in general use in a reasonable time were the fuel

control to be adopted.

We proposed to control sulfur levels in gasoline based on both of

these criteria. Under the first criterion, we believe that existing

sulfur content in gasoline used in Tier 1 and LEV technology vehicles

contributes to ozone pollution, air toxics, and PM at levels which can

be reasonably expected to endanger public health or welfare. Under the

second criterion, we believe that in the absence of gasoline sulfur

control, sulfur in fuel that would be used in Tier 2 technology

vehicles would significantly impair the emissions control systems

expected to be used in such vehicles.

EPA promulgated new NAAQS for ozone and PM10 in 1997. 62

FR 38652 (July 18, 1997); 62 FR 38856 (July 18, 1997). In proposing the

Tier 2 standards, EPA proposed its determination of air quality need

after considering data related to both the new NAAQS for ozone (the

``8-hour ozone NAAQS'') and the pre-existing ozone NAAQS (the ``1-hour

ozone NAAQS'') as well as both the new PM10 NAAQS and the

pre-existing PM10 NAAQS. Based on the data EPA believes the

need for Tier 2 and sulfur control is strongly justified for both the

new and pre-existing ozone and PM NAAQS.

B. Court Opinion

On May 14, 1999, a panel of the U.S. Court of Appeals for the

District of Columbia Circuit found, by a 2-1 vote, that sections 108

and 109 of the Clean Air Act, as interpreted by EPA, represent

unconstitutional delegations of Congressional power. American Trucking

Ass'ns, Inc., et al., v. Environmental Protection Agency, Nos. 97-1440,

1441 (D.C. Cir. May 14, 1999). The Court remanded the record to EPA.

One judge dissented, finding that the majority's opinion ``ignores the

last half-century of Supreme Court nondelegation jurisprudence.'' Id.,

slip op. at 31.

The Court also ruled on other general issues and on issues specific

to each NAAQS. The Court upheld EPA's rules on some of these claims,

but ruled against the Agency on others. Regarding the 8-hour ozone

NAAQS, the Court found that the statute permits EPA to promulgate a

revised ozone NAAQS and to designate the attainment status of areas.

However, the Court curtailed EPA's ability to require states to comply

with the revised ozone NAAQS. Further the Court directed the Agency to

determine whether tropospheric ozone has a beneficent effect, and if

so, assess ozone's net adverse health effect. The Court also ruled that

EPA's use of PM10 (rather than, for example,

PM10-2.5 3) as an indicator of coarse particulate

matter was arbitrary, in light of the separate NAAQS for

PM2.5, and vacated the new PM10 standard. The

Court invited briefing on the appropriate remedy for the

PM2.5 NAAQS, as well as the status of the previous

PM10 standard in light of the Court's ruling. In general,

the Court did not find fault with the scientific basis for EPA's

determinations regarding adverse health effects from ozone or PM.

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\3\ The Court described PM10-2.5 as the measure of particulate

matter with diameter between 2.5 and 10 micrometers.

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EPA and the Department of Justice are currently evaluating the

options concerning review of the panel's decision.

II. Effect of the Panel Decision on the Tier 2 Rule

EPA has received several questions regarding whether the decision

of the panel has any effect on the Tier 2 proposal. As discussed below,

EPA believes that, regardless of the eventual outcome of the Court

case, the proposed Tier 2 Rule is justified as a necessary and

important measure for reducing air pollutants and protecting public

health. The proposed regulations continue to conform to the statutory

requirements of the Act for the 1-hour ozone standard and the pre-

existing PM10 NAAQS.

A. Vehicle Standards

1. Proposed Determinations Under Section 202(i)

Under section 202(i), EPA must promulgate new standards for LDVs

and LDTs weighing 3750 lbs. or less if EPA determines that: (1) There

is a need for further reductions in emissions in order to attain or

maintain the national ambient air quality standards; (2) the technology

for more stringent emission standards from the affected classes is

available; and (3) such standards are needed and cost-effective, taking

into account alternative methods of attaining or maintaining the

national ambient air quality standards. EPA proposed this finding in

the May 13, 1999 NPRM. EPA continues to view its proposed finding

appropriate under the CAA after consideration of the D.C. Circuit

decision.

a. Air Quality Need

EPA continues to believe that there is a need for further

reductions in emissions to attain or maintain the ozone and

PM10 NAAQS. The NPRM discussed this need criterion in

relation

[[Page 35114]]

to both the 8-hour and the 1-hour ozone standards and in relation to

both the revised PM10 and the pre-existing PM10

standards. It is clear from the proposal that further reductions are

needed to ensure achievement of the 1-hour ozone and pre-existing

PM10 NAAQS. As described in the preamble, 72 million people

outside of California lived in 36 metropolitan areas and 2 counties

designated nonattainment under the 1-hour ozone NAAQS as of August 10,

1998, while 13 million people outside of California lived in 68

counties designated nonattainment under the pre-existing

PM10 NAAQS. 64 of the counties, with a population of about 8

million people, are not included in current ozone nonattainment areas.

Therefore, approximately 80 million people live in areas currently

designated nonattainment under one or both of the NAAQS.

Though EPA projects that ozone control programs will reduce the

number of these areas in the future, it is clear that, absent Tier 2

controls, nonattainment problems under the 1-hour ozone standard will

continue well into the future. In the proposal, EPA projected future

ozone levels by applying a ``rollback method'' to selected areas in the

region analyzed by the Ozone Transport Assessment Group

(OTAG).4 We used this method to estimate 2007 design values

for both the 8-hour and 1-hour ozone standards. The 1-hour results

indicated that eight metropolitan areas and two rural counties with a

combined population of approximately 39 million are projected to have

design values in excess of the 1-hour ozone NAAQS in 2007, after

presuming implementation of controls from the Regional Ozone Transport

Rule (ROTR).5 As indicated in Table 1, these areas would be

scattered throughout the OTAG region, including areas in Texas,

Louisiana, Indiana and throughout the northeast, indicating that

nonattainment of the 1-hour ozone standard would remain a substantial

and widespread concern.

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\4\ OTAG evaluated a region that included all or part of the

easternmost 37 states.

\5\ The design value is the calculated ozone level, based on

ozone measurements in the area, that is compared to the NAAQS to

determine compliance with the standard.

Table 1.--Metropolitan Areas/Rural Counties With Design Values Projected

To Exceed the 1-Hour Standard in 2007 Using Rollback Method With ROTR

Controls but Without Tier 2/Sulfur Controls

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

Design Value

Name (ppb) Pop'n.

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

Iberville County LA..................... 132 31,049

La Porte County IN...................... 131 107,066

Beaumont-Port Arthur, TX MSA............ 129 361,218

Hartford, CT MSA........................ 125 1,157,585

Houston-Galveston-Brazoria, TX CMSA..... 175 3,731,029

Longview-Marshall, TX MSA............... 129 193,801

Memphis, TN-AR-MS MSA a................. 125 1,007,306

New York-Northern New Jersey-Long 136 19,549,649

Island, NY-NJ-CT-PA....................

CMSA:

Philadelphia-Wilmington-Atlantic 126 5,893,019

City, PA-NJ-DE-MD CMSA.............

Washington-Baltimore, DC-MD-VA-WV CMSA.. 126 6,726,395

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

Total population........................ .............. 38,758,117

Number of metro areas................... .............. 8

Metro pop............................... .............. 38,620,002

Number of counties...................... .............. 2

County pop.............................. .............. 138,115

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a 1-hour ozone NAAQS no longer applies in a portion of the MSA.

The OTAG analysis region did not include California, and therefore

EPA does not have comparable projections of future air quality in that

state. It is important to note that California has under its authority

designed and implemented a vehicle and fuel control program, and

therefore EPA did not propose to apply the proposed Tier 2/gasoline

sulfur program in California. However, in its proposal EPA noted in

qualitative terms the importance of the Tier 2 and sulfur control

reductions to California's efforts to reach attainment with the 1-hour

ozone standard. Nine areas in California currently designated as

nonattainment, and two counties currently designated as being in

attainment, with a population of approximately 30 million, have current

design values above the 1-hour ozone NAAQS. It appears that some

California areas with an attainment deadline of 1999 will not meet that

date, and therefore will require additional emission reductions to

attain. Attainment of the 1-hour standard in the remaining areas by

their various later attainment dates remains the goal of California and

EPA, but will be challenging to accomplish. Though this regulation does

not directly regulate California vehicles, ozone levels in California

are reduced through reductions in emissions from vehicles sold outside

California that subsequently enter California temporarily or

permanently. According to California, about 7 to 10 percent of all car

and light truck travel in California takes place in vehicles originally

sold outside of California. In fact, the state of California has

recently filed an update to its State Implementation Plan for the South

Coast Air Basin that expressly claims that the Tier 2 program will lead

to four tons of reduced NOX emissions per day in the South

Coast area in 2010.6 Furthermore, low gasoline sulfur levels

would prevent poisoning of the catalysts of California vehicles that

travel outside California and later return to the state.

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\6\ California Air Resources Board, Executive Order G-99-037,

May 20, 1999, Attachment A, p. 6-7, 10.

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The 1-hour ozone design values for 2007 presented in Table 1 above

were based on an analysis approach called the ``rollback method'' that

combines modeling results for future years with recent measured ozone

levels to project future ozone levels. The general concept in this

method is to first determine the design value from the monitoring data

for a three-year base period, then

[[Page 35115]]

estimate the percentage reduction between the base year and a future

year (the year 2007 is used in Table 1) using the regional ozone

modeling system. Finally, the percentage reduction is applied to the

ambient design value to project the design value for the future year. A

more detailed discussion of this approach appears in the draft RIA.

The rollback approach was applied to both the 1-hour or 8-hour

ozone predictions in the Tier 2/gasoline sulfur proposal. EPA has more

commonly used the ``exceedence method,'' which estimates future ozone

levels from the modeling results more directly. The exceedence approach

is more consistent than the rollback method with EPA's guidance to

states regarding technical methods used to demonstrate attainment with

the existing 1-hour ozone standard. In this method, the predicted ozone

concentrations in 2007 are compared to the ozone standard of interest

to characterize whether the area is likely to experience an exceedence

of the ozone standard in the future. A more complete description of

this guidance can be found in ``Guidance on Use of Modeled Results to

Demonstrate Attainment of the Ozone NAAQS'', U.S. EPA (1996), EPA-454/

B-95-007, (June 1996).

In light of the recent Court decision, EPA is providing a more

thorough presentation of the available ozone modeling data on the need

for additional emission reductions to meet the 1-hour ozone standard,

to provide additional information for public comment.

In the ROTR, EPA used the exceedence method to determine whether

designated 1-hour nonattainment areas would be likely to experience

exceedences in 2007, considering the effects of growth and emission

control measures. EPA used an exceedence approach to estimate the

impacts of controls on 1-hour ozone concentrations because this

approach is more consistent with the 1-hour standard than a rollback

approach. The form of the 1-hour standard considers the number of

exceedences at a monitoring site over a three-year period. Year-to-year

variations in meteorological conditions can result in considerable

variation in the number of exceedences at a given location across

successive three-year periods. Using the exceedence approach based on

modeling for specific ozone episodes provides for a consistent set of

meteorological conditions over which to evaluate the effects of control

strategies on 1-hour exceedences. In moving to an 8-hour standard, EPA

changed the form of the standard from an exceedence based approach to

an average concentration based approach. Specifically, 8-hour design

values are calculated as the 3-year average of the 4th highest 8-hour

value in each year at a monitoring site. As a result of this multi-year

averaging, the effects of variations in year-to-year meteorological

conditions are reduced and thus, 8-hour design values are likely to be

more stable over time than 1-hour exceedences. The rollback method,

which is based on the average ozone reductions calculated from model

predictions, is consistent with the form and temporal stability of 8-

hour design values.

Consistent with our guidance on 1-hour attainment demonstrations

and with our reliance on the exceedence approach in the ROTR, EPA has

now analyzed the air quality modeling results using the exceedence

method. The results of this analysis are presented as supplemental

information that bears on our proposed finding regarding the need for

additional reductions in ozone precursor emissions to help areas attain

the NAAQS.

Table 2 shows results of the exceedence method for the 1-hour

standard. It lists 17 current nonattainment areas that are projected to

experience exceedences of the 1-hour standard in 2007, even after

implementation of the ROTR, the National Low Emission Vehicle Program,

the 2004 highway diesel engine standards, the Phase II nonroad diesel

engine standards, and other federal emission control

measures.7 These results indicate that there are more, and

more geographically dispersed, metropolitan areas which need further

ozone precursor emission reductions to meet the 1-hour ozone NAAQS,

than was indicated by the rollback method as reported in Table 1. The

population of these 17 areas exceeds 70 million. Details of this

analysis are given in a memo to Air Docket A-97-10, titled ``Exceedence

Method Analysis of Photochemical Modeling in Support of Tier 2/

Sulfur.''

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\7\ The deadline for submission of state implementation plans

under the ROTR was recently stayed by a panel of the Court of

Appeals for the D.C. Circuit pending further review. EPA believes

that the ROTR is fully consistent with the Clean Air Act and should

be upheld. However, it should be noted that in the absence of the

controls mandated in the ROTR, the emission reductions from the Tier

2 program would be even more necessary for compliance with the

NAAQS.

Table 2.--Metropolitan Areas Projected To Experience Exceedences of the

1-Hour Standard in 2007 or 2010, as Applicable, With ROTR Controls but

Without Tier 2/Sulfur Controls

[Does not include areas for which the 1-Hour Ozone NAAQS no longer

applies.]

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

1990

Metropolitan area population

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

Atlanta, GA MSA......................................... 2,959,500

Baton Rouge, LA MSAa.................................... 528,261

Beaumont-Port Arthur, TX MSAa........................... 361,218

Birmingham, AL MSA...................................... 839,942

Chicago-Gary-Kenosha, IL-IN-WI CMSA..................... 8,239,820

Cincinnati-Hamilton, OH-KY-IN CMSAb..................... 1,817,569

Dallas-Fort Worth, TX CMSAa............................. 4,037,282

Hartford, CT MSA........................................ 1,157,585

Houston-Galveston-Brazoria, TX CMSAa.................... 3,731,029

Los Angeles-Riverside-San Bernardino CA CMSAa, c........ 13,000,000

Louisville, KY-IN MSA................................... 949,012

Milwaukee-Racine, WI CMSA............................... 1,607,183

New York-Northern New Jersey-Long Island, NY-NJ-CT-PA 19,549,649

CMSA...................................................

Philadelphia-Wilmington-Atlantic City, PA-NJ-DE-MD CMSA. 5,893,019

Springfield, MA MSA..................................... 587,884

St. Louis, MO-IL MSA.................................... 2,492,348

[[Page 35116]]

Washington-Baltimore, DC-MD-VA-WV CMSA.................. 6,726,395

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Total Population........................................ 74,479,686

Number of Areas......................................... 17

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a = These areas are not subject to the ROTR and were modeled

accordingly.

b = 1-hour ozone NAAQS proposed to no longer apply.

c = The attainment date considered for Los Angeles-Riverside-San

Bernardino is 2010. For other listed areas, the date considered is

2007. For the former area, the possibility of 2010 exceedences without

Tier 2/Sulfur controls is inferred from the inclusion of these

reductions in the most recently submitted SIP update. For other areas,

the prediction is based on the exceedence method applied to regional

ozone modeling results.

Our preliminary analysis indicates that the proposed Tier 2/Sulfur

program would reduce the number and severity of ozone exceedences in

areas currently designated nonattainment under the existing 1-hour

ozone standard. We expect to conduct further analysis of the impact of

the Tier 2/sulfur program on exceedences of the current 1-hour ozone

standard as part of our analysis for the final rule.

EPA invites comment on the appropriateness of using the exceedence

and/or rollback method in this rulemaking for purposes of analyzing

future compliance with the 1-hour ozone NAAQS.

As discussed at length in the proposed rule, emissions from LDVs

and LDTs will represent a large percentage of emissions of ozone

precursors once the ROTR is implemented. To the extent that significant

additional reductions in precursors are needed for the areas discussed

above to attain or maintain the 1-hour ozone NAAQS, EPA believes that

reductions from LDVs and LDTs in particular will be necessary.

The NOX and sulfur dioxide emissions from LDVs and LDTs

also contribute to elevated particulate matter levels as these

emissions are transformed by physical and chemical processes in the

atmosphere. The resulting particulate matter contributes to current and

projected nonattainment with the pre-existing PM10 standard.

In the NPRM, EPA presented its projection that 33 counties outside of

California, with a population of approximately eleven million, and

twelve counties in California, with a population of about seven

million, would not be in attainment with the pre-existing

PM10 standard in 2010, absent further emission reductions

8. These projections were made during the rulemaking that

established the revised PM10 standard. The following

additional information is presented regarding current and projected

attainment of the pre-existing PM10 standard.

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\8\ The predictions of 2010 nonattainment under the pre-existing

PM10 NAAQS were made on the basis of individual counties,

not metropolitan areas. The methods used to project PM

concentrations in 2010 from 1990 emissions and ambient concentration

data introduce several sources of uncertainty. Uncertainties exist

regarding emission inventory estimates from human and natural

sources, monitoring data, and the models used to account for

physical and chemical processes in the atmosphere.

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Twenty-one of the 45 counties which EPA projected to be in

nonattainment with the pre-existing PM10 standard in 2010

are not part of metropolitan areas. In these 21 rural counties,

PM10 levels are likely to be dominated by natural events

(volcanoes, wind-blown dust, or wildfires) or by single large

industrial sources of PM10. As such, the PM and PM precursor

reductions from the Tier2/Sulfur proposal are less likely to materially

affect their attainment and maintenance of the standard, although EPA

invites comment on this issue.

Table 3 lists the 24 urban counties projected to be in

nonattainment in 2010. For two areas (Lubbock Co. and Spokane Co.)

there is specific indication that natural events are responsible for

the high PM10 levels. Also, while Philadelphia was projected

to be in nonattainment in this analysis, additional emission reductions

have since occurred there through a source shutdown, which may result

in PM10 attainment in 2010. The remaining 21 urban counties

contain about 15 million people. The reductions in PM and PM precursors

resulting from the Tier 2/Sulfur rule would help to reach and maintain

the NAAQS in such areas. Of these 21 counties and 15 million people, 17

counties and 9 million people are not included in the projected ozone

exceedence areas listed in Table 2 above.

Table 3.--Counties, in Metropolitan Areas Only, Projected Not To Attain

the Pre-Existing PM10 Standard in 2010

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

Population

Name (1990)

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

Bernalillo Co NM........................................ 480,577

Kern Co CA.............................................. 369,608

Scott Co IA............................................. 150,973

Lane Co OR.............................................. 282,912

Fresno Co CA............................................ 667,000

Haris Co TX a........................................... 2,818,199

Clark Co NV............................................. 741,368

Riverside Co CA a....................................... 1,170,413

San Bernardino Co CA a.................................. 1,418,380

Lubbock Co TX b......................................... 222,636

Ouachita Par LA......................................... 142,938

Davidson Co TN.......................................... 510,784

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New Haven Co CT a....................................... 804,219

Cass Co NE.............................................. 21,318

Philadelphia Co PA a, c................................. 1,585,577

Maricopa Co AZ.......................................... 2,122,101

Utah Co UT.............................................. 263,590

Pennington Co SD........................................ 81,343

Washoe Co NV............................................ 254,667

Yolo Co CA.............................................. 141,000

San Diego Co CA......................................... 2,498,016

Santa Cruz Co CA........................................ 229,734

Spokane Co WA d......................................... 361,333

Hancock Co WV........................................... 35,233

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

Total Population........................................ 17,373,919

Number of Areas......................................... 24

Population of 21 Areas Without Specific Indication of 15,204,373

Natural Events or Additional Emission Reduction........

Population of 17 Areas Without Specific Indication of 8,993,162

Natural Events or Additional Emission Reduction, and

Not Listed in Table 2..................................

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

a Counties in areas also projected to exceed the 1-hour ozone standard

(listed in Table 2 above).

b PM10 levels in excess of the NAAQS in Lubbock Co. TX are considered to

be due to fugitive dust from agricultural land. The area is

implementing USDA guidelines on control of fugitive dust.

c Monitored PM10 levels in excess of the NAAQS in Philadelphia Co. PA

are considered to have been due to a lead smelting operation which has

ceased operation.

d The state of Washington has submitted a Natural Events Action Plan for

Spokane Co.

Based on the above, EPA reiterates its proposed finding that there

is a need for further reductions in emissions in order to attain or

maintain the NAAQS, even when consideration is limited to the one-hour

ozone and the pre-existing PM10 NAAQS. A total of

approximately 83 million people living in 17 metropolitan areas and 17

individual metropolitan counties projected to not be in attainment of

either or both of these standards would be helped by Tier 2/Sulfur

controls. We invite comment on all the information presented in this

section of this notice.

b. Technological Feasibility and Cost-Effectiveness

EPA's NPRM proposed a determination that technology would be

available for meeting emission standards more stringent than current

levels. Indeed, the NPRM proposed a finding that the standards are

fully feasible for LDVs and LDTs. The Court's decision does not concern

this issue and therefore does not affect EPA's rationale.

The Court decision also does not change EPA's proposed

determination regarding the need for and relative cost-effectiveness of

the Tier 2 standards. The Tier 2 program, costing between $1213 and

$2134 per ton of NOX and HC reduced, compares favorably to

other possible control programs that might be used to meet the ozone

NAAQS. The Tier 2/Gasoline Sulfur proposal made a summary comparison

was made to the over 50 technologies identified in the ozone NAAQS

revision rulemaking as alternative means for reducing NOX

and VOC emissions to meet the 1-hour and 8-hour NAAQS. 64 FR 26004,

26074. The average cost effectiveness of these technologies varied from

hundreds of dollars per ton to tens of thousands of dollars per ton. If

all of the technologies identified for the ozone NAAQS analysis costing

less than $10,000/ton were implemented nationwide, they would produce

NOX emission reductions of about 2.9 million tons per year,

compared to the 2.8 million tons per year for Tier 2 once the program

is fully implemented. As summarized in the Tier 2/sulfur NPRM, we found

that these additional local emission control measures only brought 2 of

the 19 projected 8-hour ozone nonattainment areas into attainment.

While not mentioned in the Tier 2/sulfur NPRM, this same analysis

showed that these additional local emission control measures only

brought 1 of the 9 projected 1-hour ozone nonattainment areas into

attainment. Thus, there appears to be a strong need for the Tier 2 and

sulfur standards, in order for local areas to achieve, not only the 8-

hour ozone NAAQS, but also the 1-hour ozone NAAQS. In addition, as

discussed in the NPRM, the cost-effectiveness of the Tier 2 program is

within the range of the cost-effectiveness of other mobile source

control programs that have already been promulgated. Given the

continuing need for further emission reductions to comply with the 1-

hour NAAQS discussed above, we believe that the Tier 2/gasoline sulfur

control proposal is a cost effective approach for attaining and

maintaining the NAAQS.

The magnitude of emission reductions that can be achieved by this

program would be difficult to achieve from any other source category.

Given the percentage of emissions of ozone precursors that come from

LDVs and LDTs and the possible alternative control programs areas may

use to meet the ozone standard, it would be difficult to attain and

maintain the ozone NAAQS (1-hour or 8-hour) in a cost-effective manner

without substantial reductions from LDVs and LDTs.

Moreover, the monetized benefit estimates used for the benefit cost

analysis of the Tier 2/gasoline sulfur proposal are not affected by the

Court action. 64 FR 26078-79 (May 13, 1999). The estimates of benefits

are based on (a) Our estimates of the emission reductions that the rule

would produce, (b) our projections of the air quality changes that

would result from these emission reductions, (c) the changes in various

health and welfare endpoints caused by the air quality changes, and (d)

the value of reductions in those health and welfare endpoints. None of

these pieces of the benefits analysis are dependent upon the specific

level of the NAAQS. Emission reductions and related air quality changes

are determined by the requirements of the rule itself. The changes in

health and welfare effects are determined solely

[[Page 35118]]

from the underlying scientific studies relating effects and endpoint

changes. Similarly, the valuation of changes in these end points is

derived directly from the scientific literature. None of these factors

depends on the specific NAAQS level.

2. Section 202(a)

EPA's proposed vehicle standards for LDTs above 3750 pounds are

governed by the general provisions of section 202(a)(1) and (2) and

provisions of section 202(a)(3).9 Under section 202(a)(1),

EPA shall promulgate ``standards applicable to the emission of air

pollutant from any class * * * of new motor vehicles . . ., which in

his judgment cause, or contribute to, air pollution which may

reasonably be anticipated to endanger public health or welfare.'' Under

section 202(a)(2), such standards must provide appropriate lead time,

``giving appropriate consideration to the cost of compliance within

such period.'' Section 202(a)(3), applicable to heavy-duty vehicles,

requires EPA standards to ``reflect the greatest degree of emission

reduction achievable through the application of technology which the

Administrator determines will be available for the model year to which

such standards apply, giving appropriate consideration to cost, energy,

and safety factors associated with the application of such

technology.''

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\9\ The proposed evaporative standards are governed by section

202(a) and 202(k).

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The Court's decision does not address these provisions, and does

not change EPA's belief that the proposed Tier 2 standards are lawful

and appropriate under these criteria. As noted above and in the

proposal, the standards in this proposed rule would reduce emissions

that cause or contribute to ozone, particulate matter, air toxics, acid

rain, and other air pollution. We believe that the information provided

in the NPRM, as well as the information that EPA relied on in setting

the NAAQS for ozone and PM, will support a conclusion that these kinds

of air pollution can be reasonably anticipated to endanger the public

health or welfare.

Based on this and the information presented in the NPRM on the

technological feasibility and cost of emissions controls to reduce

vehicle emissions, EPA continues to believe that it is appropriate to

propose these emissions standards to reduce vehicle emissions of VOCs,

NOX and PM, given that they cause or contribute to air

pollution which may reasonably be anticipated to endanger public health

or welfare. Specifically with respect to ozone and PM, this is the case

even if one only considers reductions needed to achieve or maintain

ambient air quality at the levels of the pre-existing NAAQS. Moreover,

the Court's opinion does not address EPA's determination that the 1-

hour ozone standard fails to protect health with an adequate margin of

safety,10 and further reductions are needed. Further, the

discussion above shows that, in the absence of the Tier 2 program,

healthful air quality is not achieved even if we look only at the pre-

existing NAAQS. Moreover, as discussed above, the Court's opinion does

not change EPA's belief that the standards proposed are technologically

feasible in the time permitted, giving appropriate consideration to

cost. We seek public comment on all aspects of this supplemental

notice, including the continuing need for the proposed vehicle emission

reductions.

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\10\ The one-hour standard for ozone was set 20 years ago, in

1979, based on the science available at that time. 44 FR 8202

(1979). EPA next reviewed the ozone NAAQS in 1993, in compliance

with a court-ordered schedule, and concluded that revision was not

appropriate at that time. 58 FR 13008 (1993). EPA recognized that

its 1993 decision was based on out-of-date criteria that did not

include a large emerging database suggesting the one-hour standard

might need revision. Id. at 13013, 13018. In light of the court-

ordered deadline EPA determined to complete the review and proceed

``as rapidly as possible'' with the next review to assess the new

science. Id. at 13008, 13015-13016. Even during the course of the

1993 review, EPA's science advisors, the Clean Air Scientific

Advisory Committee (CASAC), concluded that the one-hour standard

provided ``little, if any, margin of safety.'' 61 FR 65716, 65727

(1996). In addition, several members of the CASAC panel recommended

that consideration should be given to a lower 1-hour level of 0.10

ppm to offer some protection against effects for which there was

preliminary information at that time of associations with 8-hour

exposures to ozone. Id. The criteria supporting the 1997 revision of

the ozone NAAQS confirmed that the one-hour standard was inadequate

to protect public health with an adequate margin of safety. For

example, the criteria document stated that there is ``strong

evidence that ambient exposures to ozone can cause significant

exacerbations of pre-existing respiratory disease in the general

public at concentrations below 0.12 ppm.'' U.S. EPA (1996), Air

Quality Criteria for Ozone and Related Photochemical Oxidants, EPA/

600/P-93/004abcF, p. 7-171.

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B. Gasoline Sulfur Restrictions

Under section 211(c)(1), EPA may adopt a fuel control where one or

more of the following conditions apply: (1) the emission products of

the fuel cause or contribute to air pollution which may reasonably be

anticipated to endanger public health or welfare, or (2) the emission

products of the fuel will significantly impair emissions control

systems in general use or which would be in general use were the fuel

control to be adopted. The Court's decision does not address these

provisions and does not change our view that the proposed gasoline

sulfur standards are lawful and appropriate under this criterion.

Under the first criterion, we believe that emissions products

related to sulfur in gasoline used in Tier 1 and LEV technology

vehicles contribute to ozone pollution, air toxics, and PM. The

information provided in the NPRM and in this notice, as well as the

information that EPA relied on in setting the NAAQS for ozone and PM,

support the conclusion that emissions from Tier 1 and LEV technology

vehicles contributes to these kinds of air pollution, and that these

kinds of air pollution can be reasonably anticipated to endanger the

public health or welfare. The information provided in the NPRM

indicates that when Tier 1 and LEV technology vehicles are operated on

higher-sulfur fuel, emissions which give rise to ozone, air toxics, and

PM pollution increase substantially. The sulfur levels proposed in the

NPRM would result in substantial reductions in these emissions (as

discussed more fully below) and the resulting ozone, air toxics, PM,

and other air quality problems.

Based on this and the information presented in the NPRM on the

technological feasibility and cost of controls to reduce gasoline

sulfur, EPA believes that it is appropriate to propose the gasoline

sulfur standards to reduce vehicle emissions of VOCs, NOX

and PM, given that they cause or contribute to air pollution which may

reasonably be anticipated to endanger public health or welfare. EPA

believes that reductions in gasoline sulfur would provide substantial

reductions in these emissions, and would achieve significant reductions

soon after implementation, because reducing sulfur in gasoline would

immediately reduce emissions from the existing vehicle fleet.

Specifically with respect to ozone and PM, this is the case even if one

only considers reductions needed to achieve or maintain ambient air

quality at the levels of the pre-existing NAAQS. Moreover, the Court's

opinion does not question EPA's determination that the 1-hour ozone

standard has little or no margin of safety, and further reductions are

needed. As required by Section 211(c)(2)(A) prior to regulation under

the public health or welfare criterion of Section 211(c)(1), EPA

considered all relevant medical and scientific evidence available

relating to the emissions impact of sulfur in gasoline, including its

impact on emissions of ozone precursors, PM, and air toxics. EPA also

considered whether vehicle standards under Section 202 would be

technologically and economically feasible. For the reasons

[[Page 35119]]

discussed above, the Court's opinion does not change our analysis under

section 211(c)(2)(A).

Moreover, the Court's decision is not relevant to the second

criterion of section 211(c)(1). Under this criterion, EPA is proposing

the sulfur standards based on our belief that sulfur in the gasoline

that will be used in Tier 2 technology vehicles will significantly

impair the emissions control systems expected to be used in such

vehicles. The Court's decision does not affect this proposal, as EPA's

position on the sulfur sensitivity of Tier 2 emissions control

technology is based on a technical analysis of the capability of

vehicle emission control technology.

As required by section 211(c)(2)(B) prior to regulation under this

criterion of section 211(c)(1), EPA also considered the available

scientific and economic data, including an analysis of costs and

benefits of emissions control systems that are or will be in general

use and require low sulfur fuel, and those that are or will be in

general use and do not require low sulfur fuel. As described in

Appendix D of the Regulatory Impact Analysis, EPA believes that there

are no emissions control systems for gasoline vehicles meeting the

proposed Tier 2 standards that would not require low sulfur fuel, and

therefore believes that the benefits that would be achieved through

implementation of the proposed Tier 2 and gasoline sulfur programs

cannot be achieved through the use of emission control technology that

is not sulfur-sensitive. The efficiency of catalytic converters used in

gasoline-powered vehicles is very sensitive to the level of sulfur in

gasoline. As discussed in the Regulatory Impact Analysis supporting the

rule, NOX emissions increase by about 15% in Tier 1 vehicles

as gasoline sulfur levels rise from 40 to 330 ppm. LEV technologies are

even more sensitive to sulfur, with NOX increases of 40-130%

measured in testing programs. NLEV vehicles are now being sold in the

northeastern United States and will be sold in the remainder of the

United States by 2001. A substantial portion of the NOX

emission reduction benefits from the gasoline sulfur program would

arise immediately as a result of the reductions of emissions in the

current fleet in these early years. As described in section II.A.1.b.

above, the Court's decision does not affect EPA's analysis of the costs

and benefits of the Tier 2 program or the gasoline sulfur program.

Moreover, the Court's decision is not relevant to EPA's analysis of

whether vehicle emissions control technology that is not sulfur-

sensitive will be in general use.

EPA's proposal also proposes that the sulfur standards are feasible

in the lead time provided. The Court's decision does not concern this

issue and therefore does not disturb EPA's rationale.

III. Public Comment

We seek comments on all aspects of this Supplemental document,

including the continuing need for Tier 2 emission standards for

vehicles and reducing sulfur in gasoline to attain and maintain the

NAAQS. In addition, we have just completed four public hearings around

the country on the Tier 2 proposal and continue to welcome written

public comments on the Tier 2/Gasoline sulfur proposal until the

closing date of August 2, 1999. Please see the ADDRESSES section in

this document for how and where to send any comments on the Tier 2

Proposal, as well as any comments you may have on the supplemental

information provided in today's document.

Dated: June 23, 1999.

Carol M. Browner,

Administrator.

[FR Doc. 99-16683 Filed 6-29-99; 8:45 am]

BILLING CODE 6560-50-P