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Proposed Rule To Implement the 8-Hour Ozone National Ambient Air Quality Standard

Note: EPA no longer updates this information, but it may be useful as a reference or resource.


  [Federal Register: October 21, 2003 (Volume 68, Number 203)]
[Proposed Rules]
[Page 60054-60060]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21oc03-21]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 51
[FRL-7576-8]
RIN 2060-AJ99
 
Proposed Rule To Implement the 8-Hour Ozone National Ambient Air 
Quality Standard

AGENCY: Environmental Protection Agency (EPA).
ACTION: Reopening of public comment period.

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SUMMARY: In this document, we are reopening the public comment period 
on the Proposed Rule to Implement the 8-Hour Ozone National Ambient Air 
Quality Standard (NAAQS or standard) that was published on June 2, 2003 
(68 FR 32802) to solicit additional comment on alternative approaches 
for classifying ozone nonattainment areas, based on comments received 
during the comment period. The comment period on the proposed rule 
originally closed on August 1, 2003. Based on comments received on the 
proposed rule, we are reconsidering how to classify areas and are 
giving the public the opportunity to comment on two alternative 
strategies for classifying areas.

DATES: Comments must be received on or before November 5, 2003.

[[Page 60055]]

ADDRESSES: All comments should be submitted to Docket #OAR 
2003-0079. When mailing documents, comments, or requests to the EPA 
Docket Center through the U.S. Postal Service, please use the following 
address: U.S. Environmental Protection Agency, EPA West (Air Docket), 
1200 Pennsylvania Avenue, NW., Mail Code: 6102T, Washington, DC 20460. 
To mail comments or documents through a courier service, the mailing 
address is: EPA Docket Center (Air Docket), U.S. Environmental 
Protection Agency, 1301 Constitution Avenue, NW., Room: B108; Mail 
Code: 6102T, Washington, DC 20460. The normal business hours are 8:30 
a.m. to 4:30 p.m., Monday through Friday, excluding Federal holidays. 
Comments can be submitted to the address above, by fax (202) 566-1741, or 
by e-mail to A-and-R-Docket@epa.gov. The voice telephone number is 
(202) 566-1742. In addition, we have placed a variety of materials 
regarding implementation options on the Web site: http://www.epa.gov/
ttn/naaqs/ozone/o3imp8hr. While this Web site is not an exact duplicate 
of the Air Docket, we have placed materials that we have generated and 
materials that have been submitted in an electronic format on the Web 
site. We request that comments be submitted by e-mail to facilitate 
expeditious distribution within EPA and placement on the Web site.

FOR FURTHER INFORMATION CONTACT: Mr. John Silvasi, Office of Air 
Quality Planning and Standards, U.S. Environmental Protection Agency, 
Mail Code C539-02, Research Triangle Park, NC 27711, phone number (919) 
541-5666 or by e-mail at: silvasi.john@epa.gov or Ms. Denise Gerth, 
Office of Air Quality Planning and Standards, U.S. Environmental 
Protection Agency, Mail Code C539-02, Research Triangle Park, NC 27711, 
phone number (919) 541-5550 or by e-mail at: gerth.denise@epa.gov.

SUPPLEMENTARY INFORMATION: 

I. General Information

A. How Can I Get Copies of This Document and Other Related Information?

    1. Docket. EPA has established an official public docket for this 
action under Docket ID Number OAR 2003-0079. 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 and Radiation Docket in the EPA Docket Center, EPA/DC) EPA 
West, Room B102, 1301 Constitution Ave., NW., Washington, DC. 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, and the telephone number 
for the Air and Radiation Docket is (202) 566-1742).
    2. Electronic Access. You may access this Federal Register document 
electronically through the EPA Internet 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.regulations.gov/ to submit or 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. Once in the system, select ``search,'' 
then key in the appropriate docket identification number.
    Certain types of information will not be placed in the EPA Dockets. 
Information claimed as CBI and other information whose disclosure is 
restricted by statute and which, therefore, is not included in the 
official public docket, will not be available for public viewing in 
EPA's electronic public docket. EPA's policy is that copyrighted 
material will not be placed in EPA's electronic public docket but will 
be available only in printed, paper form in the official public docket. 
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 Unit I.A.1.
    For public commenters, it is important to note that EPA's policy is 
that public comments, whether submitted electronically or in paper, 
will be made available for public viewing in EPA's electronic public 
docket as EPA receives them and without change, unless the comment 
contains copyrighted material, CBI, or other information whose 
disclosure is restricted by statute. When EPA identifies a comment 
containing copyrighted material, EPA will provide a reference to that 
material in the version of the comment that is placed in EPA's 
electronic public docket. The entire printed comment, including the 
copyrighted material, will be available in the public docket.
    Public comments submitted on computer disks that are mailed or 
delivered to the docket will be transferred to EPA's electronic public 
docket. Public comments that are mailed or delivered to the Docket will 
be scanned and placed in EPA's electronic public docket. Where 
practical, physical objects will be photographed, and the photograph 
will be placed in EPA's electronic public docket along with a brief 
description written by the docket staff.

B. How and to Whom Do I Submit Comments?

    You may submit comments electronically, by mail, by facsimile, or 
through hand delivery/courier. To ensure proper receipt by EPA, 
identify the appropriate docket identification number in the subject 
line on the first page of your comment. Please ensure that your 
comments are submitted within the specified comment period. Comments 
received after the close of the comment period will be marked ``late.'' 
EPA is not required to consider these late comments.
    1. Electronically. If you submit an electronic comment as 
prescribed below, EPA recommends that you include your name, mailing 
address, and an e-mail address or other contact information in the body 
of your comment. Also include this contact information on the outside 
of any disk or CD ROM you submit, and in any cover letter accompanying 
the disk or CD ROM. This ensures that you can be identified as the 
submitter of the comment and allows EPA to contact you in case EPA 
cannot read your comment due to technical difficulties or needs further 
information on the substance of your comment. EPA's policy is that EPA 
will not edit your comment, and any identifying or contact information 
provided in the body of a comment will be included as part of the 
comment that is placed in the official public docket, and made 
available in EPA's electronic public docket. If EPA cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment.
    i. EPA Dockets. Your use of EPA's electronic public docket to 
submit comments to EPA electronically is EPA's preferred method for 
receiving comments. Go directly to EPA Dockets at http://www.epa.gov/
edocket, and follow the online instructions for submitting comments. 
To access EPA's electronic public docket from the EPA Internet Home Page, 
select ``Information

[[Page 60056]]

Sources,'' ``Dockets,'' and ``EPA Dockets.'' Once in the system, select 
``search,'' and then key in Docket ID No. 2003-0090. The system is an 
``anonymous access'' system, which means EPA will not know your 
identity, e-mail address, or other contact information unless you 
provide it in the body of your comment.
    ii. E-mail. Comments may be sent by electronic mail (e-mail) to 
A-and-R-Docket@epa.gov, Attention Docket ID No. 2003-0090. In addition, 
in order to expedite this process, please also sent your comments to both 
silvasi.john@epa.gov and gerth.denise@epa.gov. In contrast to 
EPA's electronic public docket, EPA's e-mail system is not an 
``anonymous access'' system. If you send an e-mail comment directly to 
the Docket without going through EPA's electronic public docket, EPA's 
e-mail system automatically captures your e-mail address. E-mail 
addresses that are automatically captured by EPA's e-mail system are 
included as part of the comment that is placed in the official public 
docket, and made available in EPA's electronic public docket.
    iii. Disk or CD ROM. You may submit comments on a disk or CD ROM 
that you mail to the mailing address identified in Unit I.B.2 below. 
These electronic submissions will be accepted in WordPerfect or ASCII 
file format. Avoid the use of special characters and any form of 
encryption.
    2. By Mail. Send your comments to: Air and Radiation Docket, U.S. 
Environmental Protection Agency, Mail Code: 6102T, 1200 Pennsylvania 
Ave., NW., Washington, DC, 20460, Attention Docket ID No. OAR 2003-
0079.
    3. By Hand Delivery or Courier. Deliver your comments to: Air and 
Radiation Docket, U.S. Environmental Protection Agency, 1301 
Constitution Avenue, NW., Room: B102, Washington, DC 20004, Attention 
Docket ID No. OAR 2003-0079. Such deliveries are only accepted during 
the Docket's normal hours of operation as identified in Unit I.A.1.
    4. By Facsimile. Fax your comments to: 202-566-1741, Attention 
Docket ID No. OAR 2003-0079.

C. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide any technical information and/or data you used that 
support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at your estimate.
    5. Provide specific examples to illustrate your concerns.
    6. Offer alternatives.
    7. Make sure to submit your comments by the comment period deadline 
identified.
    8. To ensure proper receipt by EPA, identify the appropriate docket 
identification number in the subject line on the first page of your 
response. It would also be helpful if you provided the name, date, and 
Federal Register citation related to your comments.

II. Background

    On June 2, 2003 (68 FR 32802), we proposed options for implementing 
the 8-hour ozone NAAQS, including two different classification options. 
Classifications establish which requirements apply to individual 
nonattainment areas and the maximum timeframe for areas to attain. 
Option 1 would place all 8-hour ozone nonattainment areas into subpart 
2 and would classify areas in accordance with table 1 in section 181 of 
the CAA as modified by EPA to reflect the 8-hour NAAQS. Option 2 would 
place areas that are designated nonattainment for the 8-hour ozone 
standard under subpart 1 or subpart 2 (of part D, title I) based on the 
area's 1-hour ozone design value. Areas placed under subpart 2 would be 
classified in accordance with table 1 in section 181 of the Clean Air 
Act (CAA) as modified by EPA to reflect the 8-hour NAAQS. (In general, 
subpart 1 contains less prescriptive requirements for air quality 
planning than does subpart 2.) We indicated a preference for 
classification option 2 because it would provide more flexibility to 
States and Tribes as they address their unique air quality problems.
    We received many comments concerning the classification options we 
proposed. A number of commenters favored option 2, indicating that they 
believed it provided needed flexibility in implementing the standard. 
Other commenters favored option 1, indicating that they believed that 
the Supreme Court ruling established a preference for subpart 2 and, 
therefore, it was not appropriate to classify areas under subpart 1. 
Northeast States and some other States, as well as environmental 
organization commenters,\1\ objected to allowing some areas to be 
subject to subpart 1, stating that the mandatory measures under subpart 
2 helped reduce ozone concentrations and were a forcing function for 
more expeditious control. A number of other States outside the 
Northeast preferred that some areas be covered under subpart 1, because 
of the flexibility it provided to local areas to adopt controls that 
are appropriate for their area.
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    \1\ E.g., Clean Air Task Force, docket document OAR-2003-0079-
0154; Environmental Defense, docket document OAR-2003-0079-0264, -
0265, -0266; Massachusetts Department of Environmental Protection, 
docket document OAR-2003-0079-0267.
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    Several other commenters suggested new options or variants of 
option 2. There were two key concerns that seemed to be the basis for 
most of these comments. First, many commenters were concerned that 
under EPA's option 2, some areas classified under subpart 1 could have 
worse 8-hour air quality than areas classified under subpart 2.\2\ Many 
of these commenters noted that it seemed inequitable to have areas with 
more significant air quality problems subject to less stringent 
planning obligations and more flexible attainment periods. Second, a 
number of commenters raised a concern that the distribution scheme 
under a modified Table 1 resulted in too many areas in the lower 
classifications. These commenters believed that the classification for 
many areas under this approach would not reflect the significance of 
the 8-hour ozone problem for these areas and therefore would not 
provide the appropriate amount of time needed for those areas to attain 
the standard.\3\
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    \2\ See e.g., Hunton and Williams LLP representing the Utility 
Air Regulatory Group (UARG), docket document OAR-2003-0079-0362; 
Northeast States for Coordinated Air Use Management, OAR-2003-0079-
0315; Kansas City Power and Light (KCPL), docket document OAR-2003-
0079-0185; FirstEnergy Corporation, docket document OAR-2003-0079-
0218.
    \3\ See e.g., South Coast Air Quality Management District, 
docket document OAR-2003-0079-0327; E.I. duPont de Nemours, Inc., 
docket document OAR-2003-0079-0246.
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    In considering the comments on this issue, we identified several 
suggestions that we believe deserve further consideration as they may 
address some of the above-noted concerns.\4\ We are therefore re-
opening the comment period for the limited purpose of accepting comment 
on the alternatives suggested in some of the comments. While we 
recognize that this action will delay by a brief period the issuance of 
the final rule to implement the 8-hour NAAQS, we believe that the 
comments

[[Page 60057]]

submitted on classifications merit the consideration of new 
alternatives and the opportunity for the public to review and comment 
on these alternatives. Below, we provide a brief summary of several 
alternative approaches submitted in the comments and indicate the 
docket number of relevant comment documents so that any interested 
person can review those comments.\5\ We then describe two specific 
approaches for incorporating some of these suggestions into a 
classification scheme for the 8-hour standard that, based on our 
initial review of the comments, seem the most promising for improving 
the implementation framework. While we are open to comment on any of 
the ideas suggested during the initial comment period, we are most 
interested in hearing comment on the concepts we have incorporated into 
the two alternative approaches we discuss below. We also provide 
comparisons of two alternatives with our previously proposed option 2 
without the incentive feature. This does not imply that we have decided 
to not include the incentive feature, nor does it imply that we have 
decided not to adopt our proposed option 1. In addition, we may add to 
the docket additional material as it becomes available that relates to 
the two alternatives discussed below; readers should continue to check 
the electronic docket for any such material during the comment period.
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    \4\ We do not discuss all possible alternatives raised in the 
comments but rather the alternatives that we believe are most likely 
to improve the implementation framework.
    \5\ We do not attempt to cite to all comments which may have 
raised a specific alternative; rather we try to cite examples of 
comments in which the alternatives were discussed.
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    Sequential Implementation. Several commenters contended that EPA 
does not have the authority to re-write the statute by modifying Table 
1 in section 181(a) to reflect the 8-hour NAAQS (see e.g., comments 
from Electronics Industries Alliance, docket document OAR-2003-0079-
0156; and Advanced Micro Devices, Inc., docket document OAR-2003-0079-
0139). These commenters suggested that EPA adopt a sequential 
implementation scheme under which areas that are meeting the 1-hour 
NAAQS but not the 8-hour NAAQS would be designated in April 2004 as not 
meeting the 8-hour NAAQS and begin implementation under subpart 1. 
Areas that are still violating the 1-hour NAAQS would continue to 
implement the 1-hour NAAQS under subpart 2 and would not be designated 
for the 8-hour NAAQS or begin implementing that standard until the area 
attains the 1-hour NAAQS. At the time an area is designated 
nonattainment for the 8-hour NAAQS, it would be classified under 
subpart 1 for that standard. Thus all areas would be classified under 
subpart 1 for the 8-hour NAAQS. This approach would eliminate the 
inequity issue by placing all 8-hour areas under subpart 1 and would 
allow more flexibility in setting attainment dates for areas although 
the maximum attainment period would be 10 years from designation. 
However, EPA believes that this approach conflicts with the Supreme 
Court's holding that the classification provisions of subpart 2 must 
apply for purposes of implementing the 8-hour NAAQS. See Whitman v. 
ATA, 121 S. Ct. 903, 917 (2001).
    Use 8-hour design values exclusively under Option 2. Several 
commenters that supported option 2 recommended against using the 1-hour 
design value for determining which areas would be classified under 
subpart 1 and which would be classified under subpart 2. (See e.g., 
UARG, docket document OAR-2003-0079-0362; Kansas City Power & Light, 
docket document OAR-2003-0079-0185; TXU Energy docket document OAR-
2003-0079-0204.) These commenters suggested that it would be more 
logical and more consistent with the nature of the 8-hour standard for 
EPA instead to translate the lowest 1-hour design value threshold in 
Table 1 into an approximate 8-hour equivalent. (The original 
translation table we proposed appears at 68 FR 32812 (June 2, 2003).) 
They point to the record in the rulemaking which established the 8-hour 
NAAQS and suggest that the approximate 8-hour equivalent of the 0.12 
ppm 1-hour NAAQS is 0.090 ppm. [See, for instance, statement in third 
column, section D of 62 FR 38858 (July 18, 1997).]
They recommend that 
rather than translating the lower bound for marginal areas in Table 1 
of section 181 to 0.080 ppm or 0.085 ppm, EPA should start it at 0.090 
ppm or 0.091 ppm, which they believe reflects the 8-hour ``equivalent'' 
of the 1-hour NAAQS. Thus, this approach would result in 8-hour 
nonattainment areas with design values less than that lower bound being 
covered under subpart 1. This approach, unlike our June 2, 2003 
proposal, would result in all subpart 1 areas having 8-hour design 
values (an indication of the magnitude of the ozone problem) that are 
lower than any area covered under subpart 2.
    Place all areas with a design value equivalent to ``moderate'' 
under subpart 2. The American Lung Association (docket document OAR-
2003-0079-0111) suggested that under Option 2, all areas with an 8-hour 
design value equivalent to moderate or above should be classified under 
subpart 2. Thus, an area that is meeting the 1-hour standard that would 
have been classified under subpart 1 under EPA's Option 2, based on its 
8-hour design value, would instead be subject to subpart 2 if its 8-
hour design value is equivalent to or greater than the design value for 
a moderate area under Table 1 of section 181 as modified to reflect 8-
hour design values. This approach would eliminate much of the inequity 
that commenters believed could result if areas classified under subpart 
1 have more significant 8-hour air quality problems than areas 
classified under subpart 2.
    Establish classifications that better reflect an area's 8-hour 
problem. A variety of commenters were concerned that EPA's 
classification scheme places too many areas in the lower 
classifications.\6\ The commenters stated that the classification 
options lead to classifications for some areas that do not reflect the 
significance of the 8-hour problem in those areas and do not reflect 
the time needed for those areas to attain. (See, e.g., The American 
Petroleum Institute (API) docket document OAR-2003-0079-0281). They 
provided several suggestions for establishing a classification scheme 
that would classify areas in a way that better reflects their air 
quality problem. API provided 3 options while other commenters 
suggested alternatives similar to one or more of the alternatives 
suggested by API. (See e.g., ExxonMobile Refining & Supply docket 
document OAR-2003-0079-0212; Clean Air Task Force \7\ docket document 
OAR-2003-0079-0215; American Chemistry Council, docket document OAR-
2003-0079-0217.)
    API's suggested alternatives are as follows:
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    \6\ This comment was raised with respect to both Option 1 and 
Option 2.
    \7\ Their rationale was that more areas should be placed in 
higher classifications to ensure that they implement the mandatory 
control measures contemplated by Congress and have a specified rate 
of reduction out to their attainment date. However, they believed 
our rule should require all 8-hour nonattainment areas to be covered 
under subpart 2.
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    ? Maintain a rebuttable presumption that an area's 1-hour 
classification would be retained under the 8-hour standard if the 1-
hour classification was higher than the 8-hour classification.
    ? Translate the classification table using only one-half the 
percentage above the standard that each statutory classification 
threshold (or cutpoint) represents.\8\ (These percentages are

[[Page 60058]]

shown in Table 2 of the proposed rule, 68 FR at 32812, and were the 
basis for translating the 1-hour ozone values in Table 1 of section 181 
of the CAA into 8-hour ozone values.) For further description, see p. 
13 of docket document OAR-2003-0079-0281.
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    \8\ The rationale for the 50 percent adjustment was that the 8-
hour standard is more stringent than the 1-hour standard and that 
past air quality trends showed that 8-hour average ozone 
concentrations declined over the past 20 years at about half the 
rate that 1-hour averages declined. Thus, we would expect attainment 
for areas with 8-hour values a certain percentage above the standard 
to take relatively more time to attain the 8-hour standard than 
areas with 1-hour values the same percentage above the 1-hour 
standard would take to attain the 1-hour standard.
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    ? Use a distribution of classifications that mirrors more 
closely the distribution of areas in the original 1991 classifications.
    While each of these alternatives would result in more areas being 
placed in higher classifications, EPA believes that the second 
alternative would more likely result in classifications that better 
reflect an area's 8-hour ozone problem.
    3. Alternative approaches for comment. Based on these comments, we 
are reopening the comment period for consideration of two alternative 
approaches for classifying areas. The first one, Alternative A, would 
translate the classification table to 8-hour values beginning with an 
8-hour design value that, to the extent possible, would be equivalent 
to the 1-hour design value of 0.121 ppm. This could be the value 
suggested in the comment (0.091) or some other value determined upon 
further analysis to be equivalent. The EPA is in the process of 
conducting additional analysis and will be placing the results of that 
analysis in the docket within a week of publication of this notice, 
where it will be available to anyone interested in reviewing it. This 
approach could then be combined with the suggestion of translating the 
classification table for the remaining thresholds using one-half of the 
percentage above the standard which each of the classification 
thresholds represents. This alternative approach would address the two 
key concerns identified by many commenters: (1) Ensuring that areas 
classified under subpart 1 have a less significant ozone problem than 
areas classified under subpart 2; and (2) shifting areas subject to 
subpart 2 into higher classifications that better reflect their 8-hour 
problem and the time it will take them to attain.
    The second alternative approach, Alternative B, would address the 
issues of equity between subpart 1 and subpart 2 areas with a structure 
that is closer to that of our June 2, 2003 proposal. In order to 
provide sufficient time for attainment, and similar to Alternative A 
above, we would reduce the range of design values that comprise a 
classification (e.g., the range of design values for marginal areas 
under Table 1 of section 181 is 0.121 up to 0.138, the range for 
moderate areas is 0.138 up to 0.160 and so on). Under this modified 
option 2 approach--
    ? Areas with 1-hour ozone design values of 0.121 ppm or 
greater would be covered under subpart 2 and would be classified with a 
revised classification table reflecting the 8-hour ozone NAAQS and 
starting at 0.085 ppm. The range for each classification would be 
determined by using 50 percent of the range in Table 1 of section 
181.\9\
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    \9\ In the June 2, 2003 proposal, we calculated the range for 
each classification using the following formula: ((the level of the 
8-hour standard 0.08) + (0.08 x (the percent the 1-hour threshold is 
above the 1-hour standard of 0.12)/100). Rather than using this 
formula to see the bottom threshold for the marginal classification, 
we set the threshold at 0.085, which is the lowest design value of 
any area that would be designated nonattainment for the 8-hour 
standard. (See discussion at 68 FR 32812, middle column and footnote 
1 to Table 2 on same page.) If we apply the same formula using 50 
percent of the percentage that the 1-hour threshold is above the 1-
hour standard, the range of the marginal classification would shrink 
to one value, viz., 0.085 ppm, with the lower threshold for the 
moderate classification being 0.086 ppm. We believe such a result is 
not consistent with Congressional intent since it would give the 
marginal classification little or no meaning. Thus, for purposes of 
this option, we believe it makes sense to use 0.085ppm (the minimum 
exceeding value of the 8-hour standard), rather than 0.08 ppm (the 
level of the standard) for the calculation. Therefore, we used the 
following formula for establishing the classification ranges for 
this approach: (0.085 + (0.085 x (0.5 x (the percent the 1-hour 
threshold is above the 1-hour standard of 0.12))/100). As an 
indication of the difference this makes, there would only be 1 
marginal area with the lower threshold for moderate areas being 
0.086 ppm, compared to 10 marginal areas with the revised method we 
employed, where 0.091 would be the lower threshold for moderate 
areas; see Tables 1 and 2 below, which are described in the next 
section.
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    ? Areas meeting both of the following criteria would also be 
covered under subpart 2:

--1-hour design value less than 0.121 ppm and
--8-hour design value representing a classification threshold of areas 
that have relatively high magnitude of an 8-hour ozone problem, for 
example 0.091 ppm or greater. (0.091 is the lower threshold for 
moderate areas.)

    ? All other areas with a 1-hour design value of less than 
0.121 ppm would be covered under subpart 1.
    This approach would significantly reduce the number of areas under 
subpart 1 that have an 8-hour design value greater than an area under 
subpart 2, but not to the extent of Alternative A above. In addition, 
it would place several areas in higher classifications, better 
reflecting the areas' air quality problems and the time the areas need 
to attain the 8-hour standard.

Effects of Alternatives A and B

    Table 1 below illustrates how a classification table (that would 
apply in place of Table 1 in section 181 of the CAA) could be 
structured for Alternatives A and B. Columns A through E appeared in 
the June 2, 2003 proposed rule. Column F presents 50 percent of the 
percentages of column D. Columns G and H present the classification 
thresholds that could apply for Alternatives A and B.
    The June 2, 2003 proposed rule used hypothetical nonattainment 
areas for evaluation of different classification approaches. These were 
documented in the report cited in the June 2, 2003 notice \10\ and 
relied on air quality data primarily from the 3-year period 1998 to 
2000. To compare the effects of the differing alternatives, we have 
updated 8-hour design values based on air quality data from 2000 to 
2002. We have developed a list of hypothetical areas using the 2000 to 
2002 data following the same procedure for defining them as we did for 
the proposal.\11\ The same cautionary statements that applied to the 
original list apply to this list.
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    \10\ Background Information Document, Hypothetical Nonattainment 
Areas for Purposes of Understanding the EPA Proposed Rule for 
Implementing the 8-hour Ozone National Ambient Air Quality Standard. 
Illustrative Analysis Based on 1998-2000 Data. U.S. Environmental 
Protection Agency, Office of Air and Radiation, Office of Air 
Quality Planning and Standards, Draft, April 2003. Available at: 
http://www.epa.gov/ttn/naaqs/ozone/o3imp8hr/.
    \11\ REVISED: Background Information Document, Hypothetical 
Nonattainment Areas for Purposes of Understanding the EPA Proposed 
Rule for Implementing the 8-hour Ozone National Ambient Air Quality 
Standard in Relation to Re-Opened Comment Period. Illustrative 
Analysis Based on 2000-2002 Data. U.S. Environmental Protection 
Agency, Office of Air and Radiation, Office of Air Quality Planning 
and Standards, Draft, October 2003. Available at: http://www.epa.gov/
ttn/naaqs/ozone/o3imp8hr/.
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    Table 2 below provides a comparison between our proposed option 2 
(without the incentive feature) (row A) and Alternatives A and B (rows 
B and C respectively); row D provides for reference the distribution of 
the original set of classifications of 1-hour nonattainment areas in 
1991. It should be noted that under either alternative approach, 
compared with our June 2, 2003 preferred approach, fewer areas would be 
covered under subpart 1.

Other Possible Issues:

1-hour Threshold to Distinguish Between Subpart 1 and Subpart 2 
Coverage

    In our June 2, 2003, proposal, classification Option 2 relied on 
the lowest 1-hour design value in the Clean Air Act's classification 
table to

[[Page 60059]]

determine which areas were required to be covered under subpart 2, 
viz., 0.121 ppm. Under our long-standing rounding conventions, values 
between 0.121 and 0.124 inclusive round down to 0.12, which is not an 
exceedance of the 1-hour standard. Several commenters \12\ noted that 
the 0.121 ppm value does not represent an exceedance of the 1-hour 
standard due to our rounding conventions. They recommend that 0.125 ppm 
(which rounds to 0.13 ppm, an exceedance) be adopted as the cutpoint 
for determining whether an area must be covered under subpart 2. The 
likely practical effect would be to place a few additional areas under 
subpart 1. We are soliciting comment on this suggestion.
---------------------------------------------------------------------------

    \12\ E.g., American Petroleum Institute, docket document OAR-
2003-0079-0281; Michigan Chemistry Council, docket document OAR-
2003-0079-0200.
---------------------------------------------------------------------------

Five Percent Adjustment Provision

    If we change our classification scheme to have a narrower range for 
each classification, we may need to modify the provisions for the 5 
percent ``reclassification'' feature of section 181(a)(4) to reflect 
that change. The apparent intent of Congress was to allow States to 
request a different classification if an area's design value was within 
5 percent of a higher or lower classification threshold. That was based 
on the original threshold values, which were certain percentages above 
the level of the 1-hour standard. Our June 2, 2003 proposal would have 
retained the original percentages for the classification table based on 
8-hour average design values. If we adopt a classification table based 
on lower percentages above the standard, the adjustment feature might 
have to be modified to keep the same relative ``window'' of adjustment. 
For instance, using 100 percent of the percentages between the 1-hour 
design value thresholds, we would use a 5 percent adjustment, but using 
only 50 percent of those percentages, we may want to use only a 2.5 
percent adjustment, since the thresholds themselves are half as large.

Alternatives to a 50 Percent Adjustment

    As noted above, one option for addressing concerns that our 
proposed option 2 may not have provided classifications high enough to 
provide adequate time for some areas to attain the 8-hour standard was 
to use only half (50 percent) of the percentages above the 1-hour 
standard calculated for each of the classification thresholds. The 
commenters' rationale for the 50 percent adjustment was that the 8-hour 
standard is more stringent than the 1-hour standard and that past air 
quality trends information provided by the commenter for 11 
metropolitan areas showed that, on average, 8-hour average ozone 
concentrations declined over the 1998-2002 period at about half the 
rate that 1-hour averages declined. Thus, we would expect attainment 
for areas with 8-hour values a certain percentage above the standard to 
take relatively more time to attain the 8-hour standard than areas with 
1-hour values the same percentage above the 1-hour standard would take 
to attain the 1-hour standard. However, we could use another 
appropriate percentage that may be based on how soon areas are expected 
to attain the 8-hour standard based on measures that are currently in 
effect or are scheduled to go into effect. EPA is soliciting comments 
on other possible adjustments that may place areas in classifications 
that better reflect their 8-hour air quality problem and the time 
needed to attain.

    Authority: 42 U.S.C. 7408; 42 U.S.C. 7410; 42 U.S.C. 7501-7511f; 
42 U.S.C. 7601(a)(1).

    Dated: October 15, 2003.
Elizabeth Craig,
Acting Assistant Administrator for Air and Radiation.

                                                          Table 1.--Alternative Classifications
                                                [Table 1 of subpart 2 1-hour ozone classification table]
                                                          [Translation to 8-Hour Design Values]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                Translated 8-              Translated 8-   Translated 8-
                                                                                                 hour design                hour design     hour design
                                                                     CAA design                     value                      value           value
                                                                       value        Percent      thresholds      50% of     thresholds      thresholds
               Area class                                            thresholds  above 1-hour    (ppm ozone)     col. D   (ppm ozone) w/  (ppm ozone) w/
                                                                      (1-hour     ozone NAAQS    using Col D               50% of Col D    50% of Col D
                                                                     ozone ppm)                 (June 2, 2003              starting with   starting with
                                                                                                  proposal)                   0.091 *        0.085 **
A                                        B........................        C             D                   E     F                    G               H
----------------------------------------
Marginal...............................  from.....................        0.121  ............           0.085  .........           0.091           0.085
                                         up to....................        0.138        15               0.092     7.5              0.097           0.091
Moderate...............................  from.....................        0.138        15               0.092     7.5              0.097           0.091
                                         up to....................        0.16         33.333           0.107    16.6665           0.105           0.099
Serious................................  from.....................        0.16         33.333           0.107    16.6665           0.105           0.099
                                         up to....................        0.18         50               0.120    25                0.113           0.106
Severe-15..............................  from.....................        0.18         50               0.120    25                0.113           0.106
                                         up to....................        0.19         58.333           0.127    29.1665           0.116           0.110
Severe-17..............................  from.....................        0.19         58.333           0.127    29.1665           0.116           0.110
                                         up to....................        0.28        133.333           0.187    66.6665           0.150           0.142
Extreme................................  equal to or above........        0.28        133.333           0.187    66.6665           0.150          0.142
--------------------------------------------------------------------------------------------------------------------------------------------------------
* 0.09 + (0.09 x (col F/100))
** 0.085 + (0.085 x (col F/100))

[[Page 60060]]

                                                            Table 2.--Classification Options
                                                      [Counts of hypothetical nonattainment areas]
                                                                    (2000-2002 data)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                              Subpart 2                               Subpart 1
                                                                 ---------------------------------------------------------------------------------------
                                                                   Extreme    Severe-17   Severe-15   Serious   Moderate   Marginal               Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Option 2 as proposed 6/2/03.....................................          0           1           0         4         21         11          64      101
Alternative A (8-hour-only design value option).................          0           1           2         5         12         26          55      101
Alternative B (Modified Option 2)...............................          0           3           4         9         30         10          45      101
Original 1991 Classifications *.................................          1           5           7        13         30         43           2     101
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Does not account for section 185A or incomplete data areas

[FR Doc. 03-26537 Filed 10-20-03; 8:45 am]
BILLING CODE 6560-50-P 

 
 


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