[Federal Register Volume 64, Number 241 (Thursday, December 16, 1999)]
[Proposed Rules]
[Pages 70531-70548]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-31722]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[WI80-01-7311; FRL-6503-3]


Approval and Promulgation of Implementation Plans; Wisconsin; 
Ozone

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
conditionally approve the 1-hour ozone attainment demonstration State 
Implementation Plan (SIP) for the Milwaukee-Racine, Wisconsin severe 
ozone nonattainment area submitted by the Wisconsin Department of 
Natural Resources (WDNR) on April 30, 1998. This proposed conditional 
approval is based on the submitted modeling analysis and the State's 
commitments to adopt and submit a final ozone attainment demonstration 
and a post-1999 Rate of Progress (ROP) plan, including the necessary 
State air pollution control regulations to support the attainment and 
ROP plans, by December 31, 2000. We are also proposing, in the 
alternative, to disapprove this demonstration if the State does not, by 
December 31, 1999, select a control strategy associated with its 
submitted modeled analysis and an adequate motor vehicle emissions 
budget for Volatile Organic Compound (VOC) and Oxides of Nitrogen 
(NOX) for the ozone nonattainment area that complies with 
EPA's conformity regulations and that is derived from the selected 
emissions control strategy. In addition, the State must submit a 
commitment to adopt VOC rules and regulations for the plastic parts 
coating, industrial cleanup solvents, and ink manufacturing by December 
2000; and submit an enforceable commitment to conduct a mid-course 
review of the ozone attainment demonstration in 2003.

DATES: Comments must be received on or before February 14, 2000.

ADDRESSES: Written comments should be sent to: Carlton Nash, Chief, 
Regulation Development Section, Air Programs Branch (AR-18J), U.S. 
Environmental Protection Agency, 77 West Jackson Boulevard, Chicago, 
Illinois 60604.
    Copies of the State submittal and EPA's technical support document 
are available for public inspection during normal business hours at the 
following address: United States Environmental Protection Agency, 
Region 5, Air and Radiation Division, 77 West Jackson Boulevard, 
Chicago, Illinois 60604. (Please telephone Michael G. Leslie at (312) 
353-6680 before visiting the Region 5 Office.)

FOR FURTHER INFORMATION CONTACT: Michael G. Leslie, Regulation 
Development Section, Air Programs Branch (AR-18J), U.S. Environmental 
Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, 
Illinois 60604, Telephone Number (312) 353-6680.

SUPPLEMENTARY INFORMATION: This section provides background information 
on attainment demonstration SIPs for the 1-hour ozone national ambient 
air quality standard (NAAQS) and an analysis of the 1-hour ozone 
attainment demonstration SIP submittal for the Milwaukee-Racine area.

Table of Contents

I. Background Information
II. EPA's Review and Technical Information
III. Administrative Requirements

I. Background Information

A. What Is the Basis for the State's Attainment Demonstration SIP?

1. CAA Requirements
    The Clean Air Act (CAA) requires EPA to establish National Ambient 
Air Quality Standards (NAAQS) for certain widespread pollutants that 
cause or contribute to air pollution that is reasonably anticipated to 
endanger public health or welfare. CAA sections 108 and 109. In 1979, 
EPA promulgated the 1-hour 0.12 parts per million (ppm) ground-level 
ozone standard. 44 FR 8202 (Feb. 8, 1979). Ground-level ozone is not 
emitted directly by sources. Rather, emissions of nitrogen oxides 
(NOX) and volatile organic compounds (VOCs) react in the 
presence of sunlight to form ground-level ozone. NOX and VOC 
are referred to as precursors of ozone.
    An area exceeds the 1-hour ozone standard each time an ambient air 
quality monitor records a 1-hour average ozone concentration above 
0.124 ppm. An area is violating the standard if, over a consecutive 3-
year period, more than three exceedances are expected to occur at any 
one monitor. The CAA, as amended in 1990, required EPA to designate as 
nonattainment any area that was violating the 1-hour ozone standard, 
generally based on air quality monitoring data from the 3-year period 
from 1987-1989. CAA section 107(d)(4); 56 FR 56694 (Nov. 6, 1991). The 
CAA further classified these areas, based on the area's design value, 
as marginal, moderate, serious, severe or extreme. CAA section 181(a). 
Marginal areas were suffering the least significant air pollution 
problems while the areas classified as severe and extreme had the most 
significant air pollution problems.
    The control requirements and dates by which attainment needs to be 
achieved vary with the area's classification. Marginal areas are 
subject to the fewest mandated control requirements and have the 
earliest attainment date. Severe and extreme areas are subject to more 
stringent planning requirements but are provided more time to attain 
the standard. Serious areas are required to attain the 1-hour standard 
by November 15, 1999 and severe areas are required to attain by 
November 15, 2005 or November 15, 2007. The Milwaukee-Racine area is 
classified as severe and its attainment date is November 15, 2007.
    Under section 182(c)(2) and (d) of the CAA, serious and severe 
areas were required to submit by November 15, 1994, demonstrations of 
how they would attain the 1-hour standard and

[[Page 70532]]

how they would achieve reductions in VOC emissions of 9 percent for 
each three-year period until the attainment year (rate-of-progress or 
ROP). (In some cases, NOX emission reductions can be 
substituted for the required VOC emission reductions.) EPA will take 
action on the State's ROP plan in a separate rulemaking action. In this 
proposed rule, EPA is proposing action on the attainment demonstration 
SIP submitted by WDNR for the Milwaukee-Racine area. In addition, 
elsewhere in this Federal Register, EPA is proposing to take action on 
nine other serious or severe 1-hour ozone attainment demonstration and, 
in some cases, ROP SIPs. The additional nine areas are Greater 
Connecticut (CT), Springfield (Western Massachusetts) (MA), New-York-
North New Jersey-Long Island (NY-NJ-CT), Baltimore (MD), Philadelphia-
Wilmington-Trenton (PA-NJ-DE-MD), Metropolitan Washington, D.C. (DC-MD-
VA), Atlanta (GA), Chicago-Gary-Lake County (IL-IN), and Houston-
Galveston-Brazoria (TX).
    In general, an attainment demonstration SIP includes a modeling 
analysis component showing how the area will achieve the standard by 
its attainment date and the control measures necessary to achieve those 
reductions. Another component of the attainment demonstration SIP is a 
motor vehicle emissions budget for transportation conformity purposes. 
Transportation conformity is a process for ensuring that States 
consider the effects of emissions associated with new or improved 
federally-funded roadways on attainment of the standard. As described 
in section 176(c)(2)(A), attainment demonstrations necessarily include 
the estimates of motor vehicle emissions that are consistent with 
attainment, which then act as a budget or ceiling for the purposes of 
determining whether transportation plans and projects conform to the 
attainment SIP.
2. History and Time Frame for the State's Attainment Demonstration SIP
    Notwithstanding significant efforts by the States, in 1995 EPA 
recognized that many States in the eastern half of the United States 
could not meet the November 1994 time frame for submitting an 
attainment demonstration SIP because emissions of NOX and 
VOCs in upwind States (and the ozone formed by these emissions) 
affected these nonattainment areas and the full impact of this effect 
had not yet been determined. This phenomenon is called ozone transport.
    On March 2, 1995, Mary D. Nichols, EPA's then Assistant 
Administrator for Air and Radiation, issued a memorandum to EPA's 
Regional Administrators acknowledging the efforts made by States but 
noting the remaining difficulties in making attainment demonstration 
SIP submittals.1 Recognizing the problems created by ozone 
transport, the March 2, 1995 memorandum called for a collaborative 
process among the States in the eastern half of the country to evaluate 
and address transport of ozone and its precursors. This memorandum led 
to the formation of the Ozone Transport Assessment Group (OTAG) 
2 and provided for the States to submit the attainment 
demonstration SIPs based on the expected time frames for OTAG to 
complete its evaluation of ozone transport.
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    \1\ Memorandum, ``Ozone Attainment Demonstrations,'' issued 
March 2, 1995. A copy of the memorandum may be found on EPA's web 
site at http://www.epa.gov/ttn/oarpg/t1pgm.html.
    \2\ Letter from Mary A. Gade, Director, State of Illinois 
Environmental Protection Agency to Environmental Council of States 
(ECOS) Members, dated April 13, 1995.
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    In June 1997, OTAG concluded and provided EPA with recommendations 
regarding ozone transport. The OTAG generally concluded that transport 
of ozone and the precursor NOX is significant and should be 
reduced regionally to enable States in the eastern half of the country 
to attain the ozone NAAQS.
    In recognition of the length of the OTAG process, in a December 29, 
1997 memorandum, Richard Wilson, EPA's then Acting Assistant 
Administrator for Air and Radiation, provided until April 1998 for 
States to submit the following elements of their attainment 
demonstration SIPs for serious and higher classified nonattainment 
areas additionally needed to submit: (1) Evidence that the applicable 
control measures in subpart 2 of part D of title I of the CAA were 
adopted and implemented or were on an expeditious course to being 
adopted and implemented; (2) a list of measures needed to meet the 
remaining ROP emissions reduction requirement and to reach attainment; 
(3) for severe areas only, a commitment to adopt and submit target 
calculations for post-1999 ROP and the control measures necessary for 
attainment and ROP plans through the attainment year by the end of 
2000; 3 (4) a commitment to implement the SIP control 
programs in a timely manner and to meet ROP emissions reductions and 
attainment; and (5) evidence of a public hearing on the State 
submittal.4
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    \3\ In general, a commitment for severe areas to adopt by 
December 2000 the control measures necessary for attainment and ROP 
plans through the attainment year applies to any additional measures 
that were not otherwise required to be submitted earlier. (For 
example, this memorandum was not intended to allow States to delay 
submission of measures required under the CAA, such as inspection 
and maintenance (I/M) programs or reasonable available control 
technology (RACT) regulations, required at an earlier time.) Thus, 
this commitment applies to any control measures or emission 
reductions on which the State relied for purposes of the modeled 
attainment demonstration or for ROP. To the extent Wisconsin has 
relied on a commitment to submit these measures by December 2000 for 
the Milwaukee-Racine nonattainment area, EPA is proposing a 
conditional approval of the area's attainment demonstration. Some 
severe areas submitted the actual adopted control measures and are 
not relying on a commitment.
    \4\ Memorandum, ``Guidance for Implementing the 1-Hour Ozone and 
Pre-Existing PM 10 NAAQS,'' issued December 29, 1997. A copy of this 
memorandum may be found on EPA's web site at http://www.epa.gov/ttn/
oarpg/t1pgm.html. This submission is sometimes referred to as the 
Phase 2 submission. Motor vehicle emissions budgets can be 
established based on a commitment to adopt the measures needed for 
attainment and identification of the measures needed. Thus, State 
submissions due in April 1998 under the Wilson policy should have 
included a motor vehicle emissions budget.
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    Building upon the OTAG recommendations and technical analyses, in 
November 1997, EPA proposed action addressing the ozone transport 
problem. In its proposal, the EPA found that current SIPs in 22 States 
and the District of Columbia (23 jurisdictions) were insufficient to 
provide for attainment and maintenance of the 1-hour standard because 
they did not regulate NOX emissions that significantly 
contribute to ozone transport. 62 FR 60318 (Nov. 7, 1997). The EPA 
finalized that rule in September 1998, calling on the 23 jurisdictions 
to revise their SIPs to require NOX emissions reductions 
within the State to a level consistent with a NOX emissions 
budget identified in the final rule. 63 FR 57356 (Oct. 27, 1998). This 
final rule is commonly referred to as the NOX SIP Call.
3. Time Frame for Taking Action on Attainment Demonstration SIPs for 10 
Serious and Severe Areas
    The States generally submitted the SIPs between April and October 
of 1998; some States are still submitting additional revisions as 
described below. Under the CAA, EPA is required to approve or 
disapprove a State's submission no later than 18 months following 
submission. (The statute provides up to 6 months for a completeness 
determination and an additional 12 months for approval or disapproval.) 
The EPA believes that it is important to keep the process moving 
forward in evaluating these plans and, as appropriate, approving them. 
Thus, the EPA is proposing to take action on the 10 serious and severe 
1-hour ozone

[[Page 70533]]

attainment demonstration SIPs (located in 13 States and the District of 
Columbia) and intends to take final action on these submissions over 
the next 6-12 months. The reader is referred to individual dates in 
this document for specific information on actions leading to EPA's 
final rulemaking on these plans.
4. Options for Action on a State's Attainment Demonstration SIP
    Depending on the circumstances unique to each of the 10 area SIP 
submissions on which EPA is proposing action, EPA is proposing one or 
more of these types of approval or disapproval in the alternative. In 
addition, these proposals may identify additional action that will be 
necessary from the State.
    The CAA provides for EPA to approve, disapprove, partially approve 
or conditionally approve a State's plan submission. CAA section 110(k). 
The EPA must fully approve the submission if it meets the attainment 
demonstration requirement of the CAA. If the submission is deficient in 
some way, EPA may disapprove the submission. In the alternative, if 
portions of the submission are approvable, EPA may partially approve 
and partially disapprove, or may conditionally approve based on a 
commitment to correct the deficiency by a date certain, which can be no 
later than 1 year from the date of EPA's final conditional approval.
    The EPA may partially approve a submission if separable parts of 
the submission, standing alone, are consistent with the CAA. For 
example, if a State submits a modeled attainment demonstration, 
including control measures, but the modeling does not demonstrate 
attainment, EPA could approve the control measures and disapprove the 
modeling for failing to demonstrate attainment.
    The EPA may issue a conditional approval based on a State's 
commitment to expeditiously correct a deficiency by a date certain that 
can be no later than 1 year following EPA's conditional approval. Such 
commitments do not need to be independently enforceable because, if the 
State does not fulfill its commitment, the conditional approval is 
converted to a disapproval. For example, if a State commits to submit 
additional control measures and fails to submit them or EPA determines 
the State's submission of the control measures is incomplete, the EPA 
will notify the State by letter that the conditional approval has been 
converted to a disapproval. If the State submits control measures that 
EPA determines are complete or that are deemed complete, EPA will 
determine through rulemaking whether the State's attainment 
demonstration is fully approvable or whether the conditional approval 
of the attainment demonstration should be converted to a disapproval.
    Finally, EPA has recognized that in some limited circumstances, it 
may be appropriate to issue a full approval for a submission that 
consists, in part, of an enforceable commitment. Unlike the commitment 
for conditional approval, such an enforceable commitment can be 
enforced in court by EPA or citizens. In addition, this type of 
commitment may extend beyond 1 year following EPA's approval action. 
Thus, EPA may accept such an enforceable commitment where it is 
infeasible for the State to accomplish the necessary action in the 
short term.

B. What Are the Components of a Modeled Attainment Demonstration?

    The EPA provides that States may rely on a modeled attainment 
demonstration supplemented with additional evidence to demonstrate 
attainment. In order to have a complete modeling demonstration 
submission, States should have submitted the required modeling analysis 
and identified any additional evidence that EPA should consider in 
evaluating whether the area will attain the standard.
1. Modeling Requirements
    For purposes of demonstrating attainment, the CAA requires serious 
and severe areas to use photochemical grid modeling or an analytical 
method EPA determines to be as effective.5 The photochemical 
grid model is set up using meteorological conditions conducive to the 
formation of ozone. Emissions for a base year are used to evaluate the 
model's ability to reproduce actual monitored air quality values and to 
predict air quality changes in the attainment year due to the emission 
changes which include growth up to and controls implemented by the 
attainment year. A modeling domain is chosen that encompasses the 
nonattainment area. Attainment is demonstrated when all predicted 
concentrations inside the modeling domain are at or below the NAAQS or 
at an acceptable upper limit above the NAAQS permitted under certain 
conditions by EPA's guidance. When the predicted concentrations are 
above the NAAQS, an optional weight of evidence determination which 
incorporates, but is not limited to other analyses such as air quality 
and emissions trends, may be used to address uncertainty inherent in 
the application of photochemical grid models.
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    \5\ The EPA issued guidance on the air quality modeling that is 
used to demonstrate attainment with the 1-hour ozone NAAQS. See U.S. 
EPA, (1991), Guideline for Regulatory Application of the Urban 
Airshed Model, EPA-450/4-91-013, (July 1991). A copy may be found on 
EPA's web site at http://www.epa.gov/ttn/scram/ (file name: 
``UAMREG''). See also U.S. EPA, (1996), Guidance on Use of Modeled 
Results to Demonstrate Attainment of the Ozone NAAQS, EPA-454/B-95-
007, (June 1996). A copy may be found on EPA's web site at http://
www.epa.gov/ttn/scram/ (file name: ``O3TEST'').
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    The EPA guidance identifies the features of a modeling analysis 
that are essential to obtain credible results. First, the State must 
develop and implement a modeling protocol. The modeling protocol 
describes the methods and procedures to be used in conducting the 
modeling analyses and provides for policy oversight and technical 
review by individuals responsible for developing or assessing the 
attainment demonstration (State and local agencies, EPA Regional 
offices, the regulated community, and public interest groups). Second, 
for purposes of developing the information to put into the model, the 
State must select air pollution days, i.e., days in the past with bad 
air quality, that are representative of the ozone pollution problem for 
the nonattainment area. Third, the State needs to identify the 
appropriate dimensions of the area to be modeled, i.e., the domain 
size. The domain should be larger than the designated nonattainment 
area to reduce uncertainty in the boundary conditions and should 
include large upwind sources just outside the nonattainment area. In 
general, the domain is considered the local area where control measures 
are most beneficial to bring the area into attainment. Fourth, the 
State needs to determine the grid resolution. The horizontal and 
vertical resolutions in the model affect the dispersion and transport 
of emission plumes. Artificially large grid cells (too few vertical 
layers and horizontal grids) may dilute concentrations and may not 
properly consider impacts of complex terrain, complex meteorology, and 
land/water interfaces. Fifth, the State needs to generate 
meteorological data that describe atmospheric conditions and emissions 
inputs. Finally, the State needs to verify that the model is properly 
simulating the chemistry and atmospheric conditions through diagnostic 
analyses and model performance tests. Once these steps are 
satisfactorily completed, the model is ready to be used to generate air 
quality estimates to support an attainment demonstration.

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    The modeled attainment test compares model-predicted 1-hour daily 
maximum concentrations in all grid cells for the attainment year to the 
level of the NAAQS. A predicted concentration above 0.124 ppm ozone 
indicates that the area is expected to exceed the standard in the 
attainment year and a prediction at or below 0.124 ppm indicates that 
the area is expected to attain the standard. This type of test is often 
referred to as an exceedance test. The EPA's guidance recommends that 
States use either of two modeled attainment or exceedance tests for the 
1-hour ozone NAAQS: a deterministic test or a statistical test.
    The deterministic test requires the State to compare predicted 1-
hour daily maximum ozone concentrations for each modeled day 
6 to the attainment level of 0.124 ppm. If none of the 
predictions exceed 0.124 ppm, the test is passed.
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    \6\ The initial, ``ramp-up'' days for each episode are excluded 
from this determination.
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    The statistical test takes into account the fact that the form of 
the 1-hour ozone standard allows exceedances. If, over a 3-year period, 
the area has an average of one or fewer exceedances per year, the area 
is not violating the standard. Thus, if the State models a very extreme 
day, the statistical test provides that a prediction above 0.124 ppm up 
to a certain upper limit may be consistent with attainment of the 
standard. (The form of the 1-hour standard allows for up to three 
readings above the standard over a 3-year period before an area is 
considered to be in violation.)
    The acceptable upper limit above 0.124 ppm is determined by 
examining the size of exceedances at monitoring sites which meet the 1-
hour NAAQS. For example, a monitoring site for which the four highest 
1-hour average concentrations over a 3-year period are 0.136 ppm, 0.130 
ppm, 0.128 ppm and 0.122 ppm is attaining the standard. To identify an 
acceptable upper limit, the statistical likelihood of observing ozone 
air quality exceedances of the standard of various concentrations is 
equated to the severity of the modeled day. The upper limit generally 
represents the maximum ozone concentration observed at a location on a 
single day and it would be the only reading above the standard that 
would be expected to occur no more than an average of once a year over 
a 3-year period. Therefore, if the maximum ozone concentration 
predicted by the model is below the acceptable upper limit, in this 
case 0.136 ppm, then EPA might conclude that the modeled attainment 
test is passed. Generally, exceedances well above 0.124 ppm are very 
unusual at monitoring sites meeting the NAAQS. Thus, these upper limits 
are rarely substantially higher than the attainment level of 0.124 ppm.
2. Additional Analyses Where Modeling Fails To Show Attainment
    When the modeling does not conclusively demonstrate attainment, 
additional analyses may be presented to help determine whether the area 
will attain the standard. As with other predictive tools, there are 
inherent uncertainties associated with modeling and its results. For 
example, there are uncertainties in some of the modeling inputs, such 
as the meteorological and emissions data bases for individual days and 
in the methodology used to assess the severity of an exceedance at 
individual sites. The EPA's guidance recognizes these limitations, and 
provides a means for considering other evidence to help assess whether 
attainment of the NAAQS is likely. The process by which this is done is 
called a weight of evidence (WOE) determination.
    Under a WOE determination, the State can rely on and EPA will 
consider factors such as other modeled attainment tests, e.g., a 
rollback analysis; other modeled outputs, e.g., changes in the 
predicted frequency and pervasiveness of exceedances and predicted 
changes in the design value; actual observed air quality trends; 
estimated emissions trends; analyses of air quality monitored data; the 
responsiveness of the model predictions to further controls; and, 
whether there are additional control measures that are or will be 
approved into the SIP but were not included in the modeling analysis. 
This list is not an exclusive list of factors that may be considered 
and these factors could vary from case to case. The EPA's guidance 
contains no limit on how close a modeled attainment test must be to 
passing and to conclude that other evidence besides an attainment test 
is sufficiently compelling to suggest attainment. However, the further 
a modeled attainment test is from being passed, the more compelling the 
WOE needs to be.
    The EPA's 1996 modeling guidance also recognizes a need to perform 
a mid-course review as a means for addressing uncertainty in the 
modeling results. Because of the uncertainty in long term projections, 
EPA believes a viable attainment demonstration that relies on WOE needs 
to contain provisions for periodic review of monitoring, emissions, and 
modeling data to assess the extent to which refinements to emission 
control measures are needed. The mid-course review is discussed in 
section C.5.
    A detailed discussion of the attainment modeling for the Milwaukee-
Racine area is included later in this document.

C. What Is the Frame Work for Proposing Action on the Attainment 
Demonstration SIPs?

    In addition to the modeling analysis and WOE support demonstrating 
attainment, the EPA has identified the following key elements which 
must be present in order for EPA to approve or conditionally approve 
the 1-hour attainment demonstration SIPs. These elements are listed 
below and then described in detail.

CAA measures and measures relied on in the modeled attainment 
demonstration SIP
    This includes adopted and submitted rules for all previously 
required CAA mandated measures for the specific area classification. 
This also includes measures that may not be required for the area 
classification but that the State relied on in the SIP submission for 
attainment and ROP plans.

NOX reductions affecting boundary conditions Motor vehicle 
emissions budget
    A motor vehicle emissions budget which can be determined by EPA to 
be adequate for conformity purposes.

Mid-course review
    An enforceable commitment to conduct a Mid-Course Review (MCR) and 
evaluation based on air quality and emission trends. The mid-course 
review would indicate whether the adopted control measures are 
sufficient to reach attainment by the area's attainment date, or 
whether additional control measures are necessary.
1. CAA Measures and Measures Relied on in the Modeled Attainment 
Demonstration SIP
    The States should have adopted the control measures already 
required under the CAA for the area classification. Since these 10 
serious and severe areas need to achieve substantial reductions from 
their 1990 emissions levels in order to attain, EPA anticipates that 
these areas need all of the measures required under the CAA to attain 
the 1-hour ozone NAAQS.
    In addition, the States may have included control measures in its 
attainment strategy that are in addition to measures required in the 
CAA. (For serious areas, these should have already

[[Page 70535]]

been identified and adopted, whereas severe areas have until December 
2000 to submit measures necessary to achieve ROP through the attainment 
year and to attain.) For purposes of fully approving the State's SIP, 
the State will need to adopt and submit all VOC and NOX 
controls within the local modeling domain that were relied on for 
purposes of the modeled attainment demonstration.
    The following tables present a summary of the CAA requirements that 
need to be met for each serious and severe nonattainment area for the 
1-hour ozone NAAQS. These requirements are specified in section 182 of 
the CAA. Information on more measures that States may have adopted or 
relied on in their current SIP submissions is not shown in the tables. 
EPA will need to take final action approving all measures relied on for 
attainment, including the required ROP control measures and target 
calculations, before EPA can issue a final full approval of the 
attainment demonstration as meeting CAA section(d).

                   CAA Requirements for Serious Areas
 
 
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--NSR for VOC and NOX,\1\ including an offset ratio of 1.2:1 and a major
 VOC and NOX source cutoff of 50 tons per year (tpy)
--Reasonable Available Control Technology (RACT) for VOC and NOX\1\
--Enhanced Inspection and Maintenance (I/M) program
--15% volatile organic compound (VOC) plans
--Emissions inventory
--Emission statements
--Attainment demonstration
--9% ROP plan through 1999
--Clean fuels program or substitute
--Enhanced monitoring Photochemical Assessment Monitoring Stations
 (PAMS)
--Stage II vapor recovery
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\1\ Areas that are currently attaining the standard or can demonstrate
  that NOX controls are not needed can request a NOX waiver under
  section 182(f). Milwaukee is such an area, and is currently covered by
  a NOX waiver under 182(f).


                    CAA Requirements for Severe Areas
 
 
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--All of the nonattainment area requirements for serious areas
--NSR, including an offset ratio of 1.3:1 and a major VOC and NOX source
 cutoff of 25 tons per year (tpy)
--Reformulated gasoline
--9% ROP plan through attainment year
--Requirement for fees for major sources for failure to attain
------------------------------------------------------------------------

2. NOX Reductions Consistent With the Modeling Demonstration
    The EPA completed final rulemaking on the NOX SIP call 
on October 27, 1998, which required States to address transport of 
NOX and ozone to other States. To address transport, the 
NOX SIP call established emissions budgets for 
NOX that 23 jurisdictions were required to show they would 
meet through enforceable SIP measures adopted and submitted by 
September 30, 1999. The NOX SIP call is intended to reduce 
emissions in upwind States that significantly contribute to 
nonattainment problems. The EPA did not identify specific sources that 
the States must regulate nor did EPA limit the States' choices 
regarding where to achieve the emission reductions. Subsequently, a 
three-judge panel of the Court of Appeals for the District of Columbia 
Circuit issued an order staying the portion of the NOX SIP 
call rule requiring States to submit rules by September 30, 1999.
    The NOX SIP call rule establishes budgets for the States 
in which 9 of the nonattainment areas for which EPA is proposing action 
today are located. The 9 areas are: Greater Connecticut, Springfield, 
MA, New York-North New Jersey-Long Island (NY-NJ-CT), Baltimore MD, 
Philadelphia-Wilmington-Trenton (PA-NJ-DE-MD), Metropolitan Washington, 
D.C. (DC-MD-VA), Atlanta, GA, Milwaukee-Racine, WI, and Chicago-Gary-
Lake County (IL-IN).
    Emission reductions that will be achieved through EPA's 
NOX SIP call will reduce the levels of ozone and ozone 
precursors entering nonattainment areas at their boundaries. For 
purposes of developing attainment demonstrations, States define local 
modeling domains that include both the nonattainment area and nearby 
surrounding areas. The ozone levels at the boundary of the local 
modeling domain are reflected in modeled attainment demonstrations and 
are referred to as boundary conditions. With the exception of Houston, 
the 1-hour attainment demonstrations on which EPA is proposing action 
have relied, in part, on the NOX SIP Call reductions for 
purposes of determining the boundary conditions of the modeling domain. 
Emission reductions assumed in the attainment demonstrations are 
modeled to occur both within the State and in upwind States; thus, 
intrastate reductions as well as reductions in other States impact the 
boundary conditions. Although the court has indefinitely stayed the SIP 
submission deadline, the NOX SIP Call rule remains in 
effect. Therefore, EPA believes it is appropriate to allow States to 
continue to assume the reductions from the NOX SIP call in 
areas outside the local 1-hour modeling domains. If States assume 
control levels and emission reductions other than those of the 
NOX SIP call within their State but outside of the modeling 
domain, States must also adopt control measures to achieve those 
reductions in order to have an approvable plan.
    Accordingly, States in which the nonattainment areas are located 
will not be required to adopt measures outside the modeling domain to 
achieve the NOX SIP call budgets prior to the time that all 
States are required to comply with the NOX SIP call. If the 
reductions from the NOX SIP call do not occur as planned, 
States will need to revise their SIPs to add additional local measures 
or obtain interstate reductions, or both, in order to provide 
sufficient reductions needed for attainment.
    As provided in section 1 above, any controls assumed by the State 
inside the local modeling domain 7 for purposes of the 
modeled attainment demonstration must be adopted and submitted as part 
of the State's 1-hour attainment demonstration SIP. It is only for 
reductions occurring outside the local modeling domain that States may 
assume implementation of NOX SIP call measures and the 
resulting boundary conditions.
---------------------------------------------------------------------------

    \7\ For the purposes of this document, ``local modeling domain'' 
is typically an urban scale domain with horizontal dimensions less 
than about 300 km on a side, horizontal grid resolution less than or 
equal to 5 x 5 km or finer. The domain is large enough to ensure 
that emissions occurring at 8 am in the domain's center are still 
within the domain at 8 pm the same day. If recirculation of the 
nonattainment area's previous day's emissions is believed to 
contribute to an observed problem, the domain is large enough to 
characterize this.
---------------------------------------------------------------------------

3. Motor Vehicle Emissions Budget
    The EPA believes that attainment demonstration SIPs must 
necessarily estimate the motor vehicle emissions that will be produced 
in the attainment year and demonstrate that this emissions level, when 
considered with emissions from all other sources, is consistent with 
attainment. The estimate of motor vehicle emissions is used to 
determine the conformity of transportation plans and programs to the 
SIP, as described by CAA section 176(c)(2)(A). For transportation 
conformity purposes, the estimate of motor vehicle emissions is known 
as the motor vehicle emissions budget. The EPA believes that 
appropriately identified motor vehicle emissions budgets are a 
necessary part of an attainment demonstration SIP. A SIP cannot 
effectively demonstrate

[[Page 70536]]

attainment unless it identifies the level of motor vehicle emissions 
that can be produced while still demonstrating attainment.
    The EPA has determined that except for the Western MA (Springfield) 
attainment demonstration SIP, the motor vehicle emission budgets for 
all of the above areas are inadequate or missing from the attainment 
demonstration. Therefore, EPA is proposing to disapprove the attainment 
demonstration SIPs for those nine areas if the States do not submit 
motor vehicle emissions budgets that EPA can find adequate by May 31, 
2000.8 In order for EPA to complete the adequacy process by 
the end of May, States should submit a budget no later than December 
31, 1999.9 If an area does not have a motor vehicle 
emissions budget that EPA can determine adequate for conformity 
purposes by May 31, 2000, EPA plans to take final action at that time 
disapproving in full or in part the area's attainment demonstration. 
The emissions budget should reflect all the motor vehicle control 
measures contained in the attainment demonstration, i.e., measures 
already adopted for the nonattainment area as well as those yet to be 
adopted.
---------------------------------------------------------------------------

    \8\ For severe areas, EPA will determine the adequacy of the 
emissions budgets associated with the post-1999 ROP plans once the 
States submit the target calculations, which are due no later than 
December 2000.
    \9\ A final budget is preferred; but, if the State public 
hearing process is not yet complete, then the draft budget may be 
submitted. The adequacy process generally takes at least 90 days. 
Therefore, in order for EPA to complete the adequacy process no 
later than the end of May, EPA must have by February 15, 2000, the 
final budget or a draft that is substantially similar to what the 
final budget will be. The State must submit the final budget by 
April 15, 2000.
---------------------------------------------------------------------------

4. Mid-Course Review
    An MCR is a reassessment of modeling analyses and more recent 
monitored data to determine if a prescribed control strategy is 
resulting in emission reductions and air quality improvements needed to 
attain the ambient air quality standard for ozone as expeditiously as 
practicable but no later than the statutory dates.
    The EPA believes that a commitment to perform an MCR is a critical 
element of the WOE analysis for the attainment demonstration on which 
EPA is proposing action. In order to approve the attainment 
demonstration SIP for the Milwaukee-Racine area, EPA believes that the 
State must submit an enforceable commitment to perform a MCR as 
described here.10
---------------------------------------------------------------------------

    \10\ For purposes of conformity, the State needs a commitment 
that has been subject to public hearing. If the State has submitted 
a commitment that has been subject to public hearing and that 
provides for the adoption of all measures necessary for attainment, 
the State should submit a letter prior to December 31, 1999, 
amending the commitment to include the MCR.
---------------------------------------------------------------------------

    As part of the commitment, the State should commit to work with EPA 
in a public consultative process to develop a methodology for 
performing the MCR and developing the criteria by which adequate 
progress would be judged.
    For severe areas, such as Milwaukee-Racine, the States must have an 
enforceable commitment to perform the MCR, preferably following the 
2003 ozone season, the end of the review year (e.g., by and to submit 
the results to EPA by December 31, 2003). The EPA believes that an 
analysis in 2003 would be most robust since some or all of the regional 
NOX emission reductions should be achieved by that date. The 
EPA would then review the results and determine whether any States need 
to adopt and submit additional control measures for purposes of 
attainment. The EPA is not requesting that States commit now to adopt 
new control measures as a result of this process. It would be 
impracticable for the States to make a commitment that is specific 
enough to be considered enforceable. Moreover, the MCR could indicate 
that upwind States may need to adopt some or all of the additional 
controls needed to ensure an area attains the standard. Therefore, if 
EPA determines additional control measures are needed for attainment, 
EPA would determine whether to seek additional emission reductions as 
necessary from States in which the nonattainment area is located or 
upwind States, or both. The EPA would require the affected State or 
States to adopt and submit the new measures within a period specified 
at the time. The EPA anticipates that these findings would be made as 
calls for SIP revisions under section 110(k)(5) and, therefore, the 
period for submission of the measures would be no longer than 18 months 
after the EPA finding. A draft guidance document regarding the MCR 
process is located in the docket for this proposal and may also be 
found on EPA's web site at http://www.epa.gov/scram/.

D. In Summary, What Does EPA Expect To Happen With Respect to 
Attainment Demonstrations for the Severe 1-Hour Ozone Nonattainment 
Areas?

    The following table shows a summary of information on what EPA 
expects from Wisconsin to allow EPA to approve the 1-hour ozone 
attainment demonstration SIPs for Milwaukee-Racine.

 Summary Schedule of Future Actions Related to Attainment Demonstration
     for the Milwaukee-Racine Severe Nonattainment Area in Wisconsin
------------------------------------------------------------------------
   Required no later than:                       Action
------------------------------------------------------------------------
12/31/99.....................  State submits the following to EPA:
                               --Motor vehicle emissions budget.1
                               --Commitments 2 to do the following:
                                  --Submit by 12/31/00 measures for
                                   additional emission reductions as
                                   required in the attainment
                                   demonstration test.
                                  --Submit revised SIP & motor vehicle
                                   emissions budget by 12/31/00 if
                                   additional measures (due by 12/31/00)
                                   affect the motor vehicle emissions
                                   inventory.
                                  --Perform a mid-course review.
4/15/00......................  State submits in final any submissions
                                made in draft by 12/31/99.
Before EPA final rulemaking..  State submits enforceable commitments for
                                any above-mentioned commitments that may
                                not yet have been subjected to public
                                hearing.
12/31/00.....................  --State submits adopted rules that
                                reflect measures relied on in modeled
                                attainment demonstration and relied on
                                for ROP through attainment year.
                               --State revises and submits SIP & motor
                                vehicle emissions budget if the
                                additional measures are for motor
                                vehicle category.
                               --State revises and submits SIP & motor
                                vehicle emissions budget to account for
                                Tier 2 reductions as needed.3

[[Page 70537]]

 
12/31/03.....................  State submits to EPA results of mid-
                                course review.
------------------------------------------------------------------------
\1\ Final budget preferable; however, if public process is not yet
  complete, then a ``draft'' budget (the one undergoing public process)
  may be submitted at this time with a final budget by 4/15/00. However,
  if a final budget is significantly different from the draft submitted
  earlier, the final budget must be submitted by 2/15/00 to accommodate
  the 90 day processing period prior to the 5/31/00 date by which EPA
  must find the motor vehicle emissions budget adequate. Note that the
  budget can reflect estimated Tier 2 emission reductions--see
  memorandum from Lydia Wegman and Merrylin Zaw-Mon, ``1-Hour Ozone
  Attainment Demonstrations and Tier 2/Sulfur Rulemaking.''
\2\ As provided in the preamble text, the State may clarify by letter an
  existing commitment, which has been subject to public hearing, to
  submit the control measures needed for attainment. If the State has
  not yet submitted such a commitment, the State should adopt a
  commitment after public hearing. If the public hearing process is not
  yet complete, then draft commitments may be submitted at this time.
  The final commitment should be submitted no later than 4/15/00.
\3\ If the state submits such a revision, it must be accompanied by a
  commitment to revise the SIP and motor vehicle emissions budget 1 year
  after MOBILE6 is issued (if the commitment has not already been
  submitted).

E. What Are the Relevant Policy and Guidance Documents?

    This proposal has cited several policy and guidance memoranda. The 
EPA has also developed several technical documents related to the 
rulemaking action in this proposal. Some of the documents have been 
referenced above. The documents and their location on EPA's web site 
are listed below; these documents will also be placed in the docket for 
this proposal action.
Recent Documents
    1.``Guidance for Improving Weight of Evidence Through 
Identification of Additional Emission Reductions, Not Modeled.'' U.S. 
Environmental Protection Agency, Office of Air Quality Planning and 
Standards, Emissions, Monitoring, and Analysis Division, Air Quality 
Modeling Group, Research Triangle Park, NC 27711. November 1999. Web 
site: http://www.epa.gov/ttn/scram/.
    2. ``Serious and Severe Ozone Nonattainment Areas: Information on 
Emissions, Control Measures Adopted or Planned and Other Available 
Control Measures.'' Draft Report. November 3, 1999. Ozone Policy and 
Strategies Group. U.S. EPA, RTP, NC.
    3. Memorandum, ``Guidance on Motor Vehicle Emissions Budgets in 
One-Hour Attainment Demonstrations,'' from Merrylin Zaw-Mon, Office of 
Mobile Sources, to Air Division Directors, Regions I-VI. November 3, 
1999. Web site: http://www.epa.gov/oms/transp/traqconf.htm.
    4. Memorandum from Lydia Wegman and Merrylin Zaw-Mon to the Air 
Division Directors, Regions I-VI, ``1-Hour Ozone Attainment 
Demonstrations and Tier 2/Sulfur/Sulfur Rulemaking.'' November 8, 1999. 
Web site: http://www.epa.gov/oms/transp/traqconf.htm.
    5. Draft Memorandum, ``1-Hour Ozone NAAQS--Mid-Course Review 
Guidance.'' From John Seitz, Director, Office of Air Quality Planning 
and Standards. Web site: http://www.epa.gov/ttn/scram/.
    6. Memorandum, ``Guidance on the Reasonably Available Control 
Measures (RACM) Requirement and Attainment Demonstration Submissions 
for Ozone Nonattainment Areas.'' John S. Seitz, Director, Office of Air 
Quality Planning and Standards. November 30, 1999. Web site: http://
www.epa.gov/ttn/oarpg/t1pgm.html.
Previous Documents
    1. U.S. EPA, (1991), Guideline for Regulatory Application of the 
Urban Airshed Model, EPA-450/4-91-013, (July 1991). Web site: http://
www.epa.gov/ttn/scram/ (file name: ``UAMREG'').
    2. U.S. EPA, (1996), Guidance on Use of Modeled Results to 
Demonstrate Attainment of the Ozone NAAQS, EPA-454/B-95-007, (June 
1996). Web site: http://www.epa.gov/ttn/scram/ (file name: ``O3TEST'').
    3. Memorandum, ``Ozone Attainment Demonstrations,'' from Mary D. 
Nichols, issued March 2, 1995. Web site: http://www.epa.gov/ttn/oarpg/
t1pgm.html .
    4. Memorandum, ``Extension of Attainment Dates for Downwind 
Transport Areas,'' issued July 16, 1998. Web site: http://www.epa.gov/
ttn/oarpg/t1pgm.html.
    5. December 29, 1997 Memorandum from Richard Wilson, Acting 
Assistant Administrator for Air and Radiation ``Guidance for 
Implementing the 1-Hour Ozone and Pre-Existing PM10 NAAQS.'' Web site: 
http://www.epa.gov/ttn/oarpg/t1pgm.html.

II. EPA's Review and Technical Information

A. Summary of State Submittals

1. General Information
When Was the Submittal Addressed in Public Hearings, and When Was the 
Submittal Formally Submitted by Wisconsin?
    The State held a public hearing on the ozone attainment 
demonstration on April 24, 1998 and submitted it to EPA on April 30, 
1998.
What Are the Basic Components of the Submittal?
    Since Wisconsin, along with Illinois, Indiana, and Michigan, 
participated in the Lake Michigan Ozone Study and the Lake Michigan 
Ozone Control Program, and since these ozone modeling studies form the 
technical basis for the ozone attainment demonstration, Wisconsin, 
Illinois, and Indiana centered their ozone attainment demonstrations 
around a single technical support document (April 1998) produced by the 
four States through the Lake Michigan Air Directors Consortium (LADCO). 
This technical support document is entitled ``Modeling Analysis for 1-
Hour Ozone NAAQS in the Lake Michigan Area.'' Each State has also 
included a state-specific cover letter and state-specific synopsis of 
the ozone attainment demonstration. The Wisconsin ozone attainment 
demonstration submittal relies on the original Phase I submittals, 
submitted June 1996, for much of its technical documentation. The Phase 
I submittal included modeling with interim assumptions about ozone 
transport levels and future changes in these transport levels

[[Page 70538]]

2. Modeling Procedures and Basic Input Data
What Modeling Approach Was Used in the Analyses?
    All three States, as members of LADCO and as participants in the 
Lake Michigan Ozone Study and Lake Michigan Ozone Control Program, used 
the same ozone modeling approach. The modeling approach is documented 
in an April 1998 technical support document, entitled ``Modeling 
Analysis For 1-Hour Ozone NAAQS In The Lake Michigan Area.'' Since the 
April 1998 technical support document failed to document all of the 
modeling approaches and bases for the development and selection of 
model input data, this review also relies on the Phase I submittal, 
which does a more thorough job of documenting the system and input 
data.
    The heart of the modeling system and approach is the Urban Airshed 
Model--Version V (UAM-V) developed originally for application in the 
Lake Michigan area. This photochemical model was used to model ozone 
and ozone precursors in a multiple, nested grid system. In the 
horizontal dimension, three nested grids were used. Grid A, the largest 
of the three grids, is a 35 cell by 50 cell grid (560 kilometers east-
west by 800 kilometers north-south) generally centered on the lower 
two-thirds of Lake Michigan with a horizontal resolution of 16 
kilometers per cell. Grid B is a 34 cell by 60 cell grid (272 
kilometers east-west by 480 kilometers north-south) centered on the 
lower three-quarters of Lake Michigan with a horizontal resolution of 8 
kilometers per cell. Grid B covers all of the one-hour ozone 
nonattainment areas of interest in the analysis. Grid C is a 20 cell by 
80 cell grid (80 kilometers east-west by 320 kilometers north-south) 
approximately centered on the western shoreline of lower Lake Michigan 
with a horizontal resolution of 4 kilometers per cell. The model 
covered 8 vertical layers over the entire horizontal modeling domain. 
Mixing heights used in the modeling system were determined from 
regional upper-air monitoring station data.
    Besides being able to model ozone and other pollutants in nested 
horizontal grids, UAM-V can also model individual elevated source 
plumes within the modeling grid (plume-in-grid or PiG). Gaussian 
dispersion models are used to grow plumes until the plumes essentially 
filled grid cells. At these points, the numerical dispersion and 
advection components of UAM take over to address further downwind 
dispersion and advection.
    The UAM-V modeling system is also used to assess the impacts of 
clouds on certain high ozone episode days. Observed cloud data are used 
to modify chemical photolysis rates and other meteorological input 
data.
    The following input data systems and analyses were also used as 
part of the combined modeling system for the Lake Michigan area:
    a. Emissions. UAM-V requires the input of gridded, hourly estimates 
of CO, NOX, and speciated VOC emissions (speciated based on 
carbon bond types). The States provided emission inventories, which 
were processed through the Emissions Modeling System--1995 version 
(EMS-95) to prepare UAM-V input data files. Emission data files were 
generated for Grid A and Grid B.
    For Grid B, the States supplied point source (individually 
identified stationary sources) and area source (sources too small and 
numerous to be identified and recorded as individual sources) emissions 
for a typical summer weekday. These emissions were based on the States' 
1990 base year emissions inventories for the ozone nonattainment areas 
and were adjusted to 1991 levels to be compatible with the high ozone 
periods modeled. The base emissions were adjusted for some source 
categories to reflect typical ``hot summer days.'' Day-specific 
emissions data were supplied by over 200 facilities in the modeling 
domain. Mobile source emissions were calculated by EMS-95 using 
MOBILE5a (a mobile source emissions model supplied by the Environmental 
Protection Agency) emission factors (using day-specific temperatures) 
and local vehicle-miles-traveled data generally supplied by local 
metropolitan planning agencies and based on transportation models. 
Finally, the biogenic emission rates used in Grid B were calculated 
based on BIOME, which is the biogenics emissions model contained within 
EMS-95.
    For Grid A, point and area anthropogenic emissions rates were 
derived from EPA's 1990 Interim Regional Inventory, except for 
Wisconsin, which supplied state-specific data. Mobile source emissions 
were based on MOBILE5a emission factors (derived for a representative 
hot summer day) and vehicle miles traveled data derived using the 1990 
Highway Performance Monitoring System. Biogenic emission rates were 
calculated using the Biogenics Emissions Inventory System (BEIS) 
assuming temperatures for a representative, hot summer day. This 
version of BEIS includes soil NOX emissions and land use 
data from the United States Geological Survey.
    Grid B emissions data superceded Grid A data within Grid B. Grid C 
emissions data were not specifically derived--Grid B emissions data 
were used within Grid C.
    All emission estimates were speciated by compound or carbon bond 
type and spatially, and temporally resolved into UAM-V input data files 
by the use of EMS-95.
    b. Meteorology. Meteorological input data by grid cell and hour 
were generated by use of a prognostic meteorological model (model 
output data derived from equations which describe how meteorological 
variables, such as wind speed/direction, temperature, and water vapor 
change over time) known as CALRAMS. CALRAMS was run with varying 
horizontal resolution depending on location. Over Grids B and C, 
CALRAMS was run with 4 kilometer resolution. Over Grid A, a resolution 
of 16 kilometers was used. Over the remainder of the continental United 
States, a resolution of 80 kilometers was used. The model's vertical 
structure used 31 layers in Grid A and over the remainder of the 
continental United States outside of the UAM-V modeling domain and 26 
layers over Grids B and C.
    Four-dimensional data assimilation using observed meteorological 
data values was used to ensure that the model estimates did not deviate 
significantly from observed meteorological data. Preprocessor programs 
were used to map the model's output data into the UAM-V grid system and 
to derive other necessary model inputs.
    Some adjustments were made to CALRAMS results where the model 
produced near-calm wind speeds and where observed wind speeds were 
significantly higher than modeled wind speeds during one modeled ozone 
episode.
    c. Chemistry Atmospheric chemistry within the modeling grid system 
and UAM-V was simulated using the Carbon Bond-Version IV model 
developed by the Environmental Protection Agency and used in Version IV 
of UAM.
    d. Boundary and Initial Conditions. Initial sensitivity analyses of 
the modeling system's response to modeling domain boundary conditions 
(incoming ozone and ozone precursor levels at the outer edges of the 
modeling domain) showed that the system was very sensitive to these 
boundary conditions. LADCO used all available upwind data, and 
especially those collected during the 1991 intensive field study, to 
derive boundary conditions. In addition, the

[[Page 70539]]

contractor, SAI, Incorporated, used output data from the use of the 
Regional Oxidant Model (ROM) to derive initial concentrations in the 
modeling domain for the first day of each modeled ozone episode. Data 
from this first day, along with other model input data, were used to 
model ozone and precursor concentrations for the next 1 to 2 days, to 
be used as inputs into the main part of the modeled ozone episode. The 
first 1 to 2 days modeled were treated as ``ramp-up days'' for the main 
part of each modeled ozone episode. This process produced more stable 
input data for the modeling of high ozone days.
What high ozone periods were modeled?
    Four high ozone episodes in 1991 were considered. These episodes 
were:

June 18-21, 1991;
June 24-28, 1991;
July 15-19, 1991; and
August 22-26, 1991.

The 1991 ozone episodes were selected as the focus of the modeling 
analyses because the summer of 1991 was a relatively conducive period 
for ozone formation, and, most importantly, because LADCO conducted an 
intensive field study during that summer to collect data needed to 
support the modeling study.
What Procedures and Sources of Projection Data Were Used To Project the 
Emissions to Future Years?
    The future year emission inventories used in the Lake Michigan 
Ozone Control Program and ozone attainment demonstration were derived 
from the Lake Michigan Ozone Study base year regional inventory 
(discussed above). Three adjustments were made to the base year 
emissions inventory to generate the future year emission inventories. 
First, a baseline inventory was prepared by replacing the day-specific 
emissions with typical hot summer day emissions for point sources. 
Emissions for other source categories were simply carried over to the 
baseline inventory. Second, the baseline emissions inventory was 
projected to 2007 (the attainment year for severe ozone nonattainment 
areas) by applying scalar growth factors. Finally, the projected 
baseline emission inventories were reduced to reflect the 
implementation of various emission control measures expected or 
required to occur by those years.
    The growth factors used in the projection of emissions for each 
source sector are as follows:
    a. Point Sources. i. For electric utilities--company-specific data 
were provided by each State;
    ii. For certain individual point sources--a growth factor of ``0'' 
was used to reflect the shutdown of these sources;
    iii. For all remaining point source emission categories--growth 
factors based on the Environmental Protection Agency Economic Growth 
Analysis System (EGAS) were used;
    b. Area Sources. i. For baseline emission estimates based on 
population--projected populations were used to recalculate emissions;
    ii. For gasoline marketing source categories--projected emissions 
were based on projected gasoline sales;
    iii. For other area source emission categories--projections were 
based on EGAS estimates (some EGAS estimates were judged to be 
inappropriate and alternative surrogates were used to estimate future 
emissions);
    c. Mobile Sources. Vehicle miles traveled projections were based on 
transportation modeling for northeast Illinois, northwest Indiana, and 
southeast Wisconsin, and on State-supplied growth factors for the rest 
of the ozone modeling domain; and
    d. Biogenic Sources. No growth was assumed.
    To account for emission changes resulting from various emission 
controls (these emission controls also affect projected emissions), the 
States tested several emission control strategies. Emission reduction 
scalars were developed to reflect the expected or required emission 
reduction levels, rule penetration (accounting for the percentage of 
source category emissions affected by the emission reduction 
requirements), and rule effectiveness (some source control rules do not 
fully achieve the emission reductions expected due to control device 
failure, human error, or other factors). The base component of these 
control strategies were the emission reductions resulting from the 
controls mandated by the Clean Air Act and expected to be in place by 
2007. These emission controls are further discussed below.
How Were the Emissions, Air Quality, and Meteorological Input Data 
Quality Assured?
    Emissions. The Lake Michigan States' quality assurance of the 
emissions data focused on the comprehensiveness and reasonableness of 
the emissions data rather than on precision and accuracy of the data. 
During the initial development of the regional emissions inventory, 
internal quality control activities included the preparation and 
implementation of quality assurance plans for the derivation of 
emission estimates by each State and for the development and 
application of the EMS-95 emissions software. External quality 
assurance activities included: (1) Audits of the point and area source 
data inputs; (2) review of the EMS-95 output; and (3) independent 
testing of the EMS-95 model source code. The State emission estimates 
were compared against each other to assess their completeness, 
consistency, and reasonableness.
    Several approaches were used to compare the emission estimates 
against ambient measurements. These included: (1) Comparisons of 
ambient to emissions-based ratios of non-methane organic compounds to 
oxides of nitrogen; (2) comparisons of ambient to emissions-based 
ratios of carbon monoxide to oxides of nitrogen; (3) receptor modeling 
(determining individual source shares of monitored pollutant 
concentrations based on source-specific emission profiles and temporal 
and spatial statistical analyses of monitored pollutant species); and 
(4) comparisons of ambient to model-based ratios of non-methane organic 
compounds to oxides of nitrogen. The comparison of the measurement-
based pollutant ratios with the emissions inventory-based pollutant 
ratios showed good agreement between the emissions inventory and the 
ambient data. The receptor modeling results also generally supported 
the validity of the emissions inventory.
    Air Quality and Meteorological Data. Validation of the 1991 Lake 
Michigan Ozone Study field data (the data used as input to the 
meteorological and photochemical dispersion models and used to validate 
the models' outputs) was performed by the Lake Michigan Ozone Study 
Data Management and Data Analysis Contractors. The data were validated 
using a number of statistical analyses. Three levels of validation were 
used, depending on the intended use of the data. The three levels of 
data validation were:
    a. Level 1. This validation was performed by the group collecting 
the data. This group: flagged suspect data values; verified the data 
contained in computer data files against input data sheets; eliminated 
invalid measurements; replaced suspect data with data from back-up data 
acquisition systems; and adjusted measurement values to eliminate 
quantifiable calibration and interference biases;
    b. Level 2. This validation was performed on data assembled in a 
master data base. The level of data validation involved various 
consistency checks between data values within the data base, including: 
comparison of data from closely located sites collected at

[[Page 70540]]

approximately the same time; comparison of data from co-located 
sampling systems; comparisons based on physical relationships; and 
special statistical analyses of the VOC and carbonyl data; and
    c. Level 3. This validation was performed by the Lake Michigan 
Ozone Study Data Analysis Contractor and was performed as part of the 
data interpretation process. This validation included identification of 
unusual data values (e.g. extreme values, values which fail to track 
the values of other associated data in a time series, or those values 
which did not appear to fit the general and spatial or temporal overall 
pattern).
    As a result of the data validation, several changes were made to 
the meteorological and air quality input data. Volume III (December 
1995) of the Lake Michigan Ozone Study/Lake Michigan Ozone Control 
Program Project Report (submitted as the documentation for the Phase I 
attainment demonstration submittal) documents all of the data changes 
resulting from the data validation efforts.
3. Modeling Results
How Did the States Validate the Photochemical Modeling Results?
    A protocol document outlining the operational and scientific 
evaluation of the modeling system was prepared by LADCO, and was 
approved by the Environmental Protection Agency on March 6, 1992. The 
evaluation of the photochemical model consisted of seven steps:
    a. Evaluation of the scientific formulation of the model by the 
Photochemical Modeling Contractor;
    b. Assessment of the fidelity of the computer codes to scientific-
formulation, governing equations, and numerical solution procedures 
performed by an independent contractor (independent of the 
Photochemical Modeling Contractor);
    c. Evaluation of the predictive performance of the individual 
modeling process modules and preprocessor modules to identify possible 
flaws or systematic biases;
    d. Evaluation of the full model's predictive performance against 
statistical performance tests and performance criteria specified by the 
Environmental Protection Agency (see discussion of the model's 
performance for specific days modeled below);
    e. Performance of sensitivity tests to assure conformance of the 
model with known or expected model behavior;
    f. Performance of comparative modeling analyses, comparing the 
results from the use of UAM-V with similar results from the use of UAM-
IV (the photochemical model generally recommended by the Environmental 
Protection Agency); and
    g. Implementation of quality control and quality assurance 
activities, including: (i) Benchmark modeling; (ii) pre-established 
file structuring; (iii) duplicative modeling; (iv) modeling procedure 
and results documentation; and (v) external review of modeling results.
    Numerous modeling runs and overall system evaluations were 
conducted to carry out these validation procedures.
What Were the Results of the Model Performance Evaluations for the 
Modeling System Used in the Attainment Demonstration?
    The following highlights the results of the operational and 
scientific evaluation of the modeling system. These results are 
discussed in detail in many documents generated by LADCO and supplied 
to the EPA:
    a. Many modeling runs and evaluations of output data were made to 
derive statistical results indicative of the modeling system's overall 
performance. Statistical data, such as: Observed peak ozone 
concentrations versus peak predicted concentrations; unpaired peak 
concentration accuracy; bias in peak concentrations and overall system 
bias; and gross system error, were compared to acceptable system 
criteria specified by the Environmental Protection Agency (Guideline 
for Regulatory Application of the Airshed Model, EPA-450/4-91-013, July 
1991). The statistical accuracy results for the modeling system comply 
with the Environmental Protection Agency performance criteria;
    b. The spatial and temporal representation of the surface ozone 
concentrations are reasonable both region-wide and in the areas of high 
concentrations. Broad areas of high ozone concentrations were 
reproduced successfully and magnitude and times of peak ozone 
concentrations reasonably matched those observed;
    c. Model performance across the full modeling domain was consistent 
with model performance in individual subregions. This further supports 
the credibility of the modeling system;
    d. Predicted aloft downwind ozone concentrations compare favorably 
with airborne/aircraft monitored ozone concentrations. This supports 
the three-dimensional validity of the modeling system; and
    e. Model performance for ozone precursors, especially for 
NOX, was very good. This further supports the validity of 
the use of the model to evaluate the impacts on ozone due to changes in 
precursor emissions and the testing of the emission control strategy 
scenarios.
    Based on the model performance evaluation results, the EPA's 
approved the validity of the modeling system and its use for control 
strategy evaluations on December 15, 1994 (letter from John Seitz, 
Director of the Office of Air Quality Planning and Standards to Lake 
Michigan Air Directors Consortium).
What Were the Ozone Modeling Results for the Base Period and for the 
Future Attainment Period?
    Many modeling runs were conducted, producing millions of model 
output data. What is summarized in Tables 1 and 2 are the observed and 
modeled peak ozone concentrations for the selected ozone episode days 
for two considered emission control strategies. Please note that the 
ozone control strategy covered by each table is further discussed 
below.
    The ozone modeling system was run to simulate ozone concentrations 
on selected high ozone days for the base year and future year (2007). 
The future year simulations covered five boundary condition scenarios, 
corresponding to base year boundary conditions, and to the reduction of 
peak boundary ozone levels to 85, 80, 70, and 60 parts per billion 
(ppb), one-hour average. The future year simulations also covered two 
emission control strategy sets, Strategy 2 and Strategy 4.
    The resulting domain-wide modeled peak ozone concentrations for 
Strategy 2 are given in Table 1. Similarly, the resulting domain-wide 
modeled peak ozone concentrations for Strategy 4 are given in Table 2.

[[Page 70541]]



                                     Table 1.--Lake Michigan Ozone Control Program Strategy 2 Ozone Modeling Results
                                                      [Domain-wide Peak Ozone Concentrations, ppb]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                        2007  85     2007  80     2007  70     2007  60
                          1991  Date                            1991  OBS    1991  MOD   2007  BY BC      ppb          ppb          ppb          ppb
--------------------------------------------------------------------------------------------------------------------------------------------------------
June 26......................................................          175          165          141          134          133          128          122
June 27......................................................          118          152          130          123          122          119          114
June 28......................................................          138          142          123          118          118          116          109
June 20......................................................          152          137          123          121          121          120          120
June 21......................................................          134          126  ...........  ...........  ...........  ...........          114
July 17......................................................          145          148          133          126          124          120          113
July 18......................................................          170          162          146          135          135          128          119
July 19......................................................          170          161          145          137          137          129          119
Aug 25.......................................................          148          128          126          121          120          116          109
Aug 26.......................................................          189          158          142          135          131          124          115
--------------------------------------------------------------------------------------------------------------------------------------------------------
 AOBS = Observed Peak Ozone Concentration.
 AMOD = Modeled Base Year Peak Ozone Concentration.
 ABY BC = Base Year Boundary Conditions.
 A85 ppb, 80 ppb, 70 ppb, 60 ppb = Future Year Peak Ozone Boundary Concentrations.


                                     Table 2.--Lake Michigan Ozone Control Program Strategy 4 Ozone Modeling Results
                                                      [Domain-wide Peak Ozone Concentrations, ppb]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                        2007  85     2007  80     2007  70     2007  60
                          1991  Date                            1991  OBS    1991  MOD   2007  BY BC      ppb          ppb          ppb          ppb
--------------------------------------------------------------------------------------------------------------------------------------------------------
June 26......................................................          175          165          137          130          129          124          117
June 27......................................................          118          152          125          117          117          114          109
June 28......................................................          138          142          119          114          114          112          104
June 20......................................................          152          137          117          117          117          117          116
June 21......................................................          134          126          121          118          117          115          110
July 17......................................................          145          148          132          123          121          116          110
July 18......................................................          170          162          141          131          129          123          115
July 19......................................................          170          161          140          131          129          123          114
Aug 25.......................................................          148          128          125          120          119          115          108
Aug 26.......................................................          189          158          139          133          129          122          113
--------------------------------------------------------------------------------------------------------------------------------------------------------
 AOBS = Observed Peak Ozone Concentration.
 AMOD = Modeled Base Year Peak Ozone Concentration.
 ABY BC = Base Year Boundary Conditions.
 A85 ppb, 80 ppb, 70 ppb, 60 ppb = Future Year Peak Ozone Boundary Concentrations.

Do the Modeling Results Demonstrate Attainment of the Ozone Standard?
    The modeling of the Strategy 2 and Strategy 4 impacts by themselves 
(the 2007 BY BC columns in Tables 1 and 2) does not demonstrate 
attainment. The modeling supports the need for significant reductions 
in background ozone and ozone precursor concentrations. In addition, 
the model indicates the potential for ozone exceedances or ozone 
standard violations under the scenarios of smaller reductions in 
background ozone levels.
Does the Attainment Demonstration Depend on Future Reductions of 
Regional Emissions?
    As noted in the tables summarizing the peak modeled ozone 
concentrations above and in the discussion elsewhere in this proposed 
rulemaking, the States considered emission control strategies which by 
themselves would not achieve attainment of the one-hour ozone standard. 
The States, however, also show that, with a significant reduction in 
background ozone concentrations expected to result from the 
implementation of regional NOX emission controls under the 
NOX SIP call, attainment of the standard can be achieved 
using the control strategies considered. Strategy 2 can lead to 
attainment of the ozone standard with a future reduction in peak ozone 
background concentrations down to 70 ppb. Strategy 4 can lead to 
attainment if peak background ozone concentrations are reduced to 80 
ppb. LADCO documents that these future ozone background concentration 
levels may be obtained through the implementation of the NOX 
emission controls required in the NOX SIP.
    It should be noted that LADCO not only considered lowered 
background ozone concentrations resulting from regional upwind emission 
controls, they also considered reductions in background ozone precursor 
concentrations. The States used various analyses to estimate the 
reductions in background ozone precursor concentrations associated with 
the assumed reductions in background ozone concentrations. This was 
primarily accomplished by considering available modeling data from 
OTAG.
    The following two step process was used to determine which of the 
tested boundary conditions correspond best to the boundary conditions 
that would be expected under EPA's NOX SIP call:
    a. The NOX emissions of the OTAG modeling domain were 
compared to the regional NOX emissions expected under the 
NOX SIP call. Several emission control strategies considered 
in the OTAG process were assessed. It is noted that the SIP Call level 
of NOX emissions fall between OTAG emission control strategy 
runs C and H; and
    b. The boundary ozone concentration changes resulting from the 
selected OTAG strategy runs were then compared to the ozone boundary 
changes considered in the Lake Michigan Ozone Control Program modeling 
runs. The reduction of peak background ozone levels down to 70 ppb in 
the Lake Michigan Ozone Control Program was found to correspond best 
with the expected

[[Page 70542]]

ozone changes considered under the selected OTAG emission control 
strategy runs C through H.
    Based on this approach, it is assumed that the NOX SIP 
Call will reduce peak background ozone levels to 70 ppb.
4. Application of Attainment Test and the Attainment Demonstration
What Approach Was Used To Demonstrate Attainment of the Ozone Standard?
    To assess attainment of the one-hour ozone standard, LADCO applied 
two approaches to review the results of emission control strategy 
modeling, supplementing them with modeling results from the OTAG 
process. First, the States considered the modeling results through the 
use of a deterministic approach. Second, the States considered a 
statistical approach.
    a. Deterministic Approach. The deterministic approach to ozone 
attainment demonstrations, as defined in the Guidance on the Use of 
Modeled Results to Demonstrate Attainment of the Ozone NAAQS (June 
1996), requires the daily peak one-hour ozone concentrations modeled 
for every grid cell (in the surface level) to be at or below the ozone 
standard for all days modeled. If there are modeled ozone standard 
exceedances in only a few grid cells on a limited number of days, this 
approach can still be used to demonstrate attainment of the ozone 
standard through the use of weight-of-evidence determinations.
    The States note that the deterministic test is passed for:
    i. Strategy 2 with future (2007) ozone boundary concentrations 
capped at 60 ppb; or
    ii. Strategy 4 with future ozone boundary concentrations capped at 
70 ppb.
    Note that Strategy 2 with a future ozone boundary concentration of 
70 ppb or Strategy 4 with a future ozone boundary concentration of 80 
ppb produces peak ozone concentrations that may demonstrate attainment 
given supporting weight-of-evidence analysis. The modeling results for 
other Strategy 2 and Strategy 4 scenarios with higher ozone boundary 
concentrations, however, do not appear to be close enough to the 
standard to warrant the consideration of weight-of-evidence.
    b. Statistical Approach. The States note that the statistical 
approach permits occasional ozone standard exceedances and reflects an 
approach comparable to the form of the one-hour ozone standard. 
Therefore, the States have also given this approach some attention.
    Under the statistical approach, there are three benchmarks related 
to the frequency and magnitude of allowed exceedances and the minimum 
level of air quality improvement after emission controls are applied. 
All three benchmarks must be passed in the statistical approach, or if 
one or more of the benchmarks are failed, the attainment demonstration 
must be supported by a weight-of-evidence analysis.
    i. Limits on the Number of Modeled Exceedance Days. This benchmark 
is passed when the number of modeled exceedances days in each subregion 
is less than or equal to 3 or N-1 (N is the number of severe days), 
whichever is less. To determine the number of severe days, the States 
concluded that a day is severe if there are at least two nonattainment 
areas within the modeling domain with observed one-hour peak ozone 
concentrations greater than the corresponding ozone design value 
(generally the fourth highest daily peak one-hour ozone concentration 
at a monitor during a three year period) during the 1990 through 1992 
period. The States conclude that only two modeled days, June 26 and 
August 26, 1991, are severe ozone days. Therefore, N is 2.
    Based on a review of the modeled daily peak ozone concentrations, 
the States conclude that Strategy 2 with a maximum background ozone 
concentration of 60 ppb and Strategy 4 with a maximum background ozone 
concentration of 70 ppb would clearly pass this benchmark test. They 
also conclude that Strategy 2 with a future maximum background ozone 
concentration of 70 ppb and Strategy 4 with a maximum background ozone 
concentration of 80 ppb would also pass the benchmark based on an 
additional weight-of-evidence analysis. The weight-of-evidence analysis 
is based on the following evidence:

A. Factors Providing Confidence in Modeled Results

    Evaluation of the modeling system's performance show that:
     Statistical measures for ozone comply with EPA's model 
performance criteria;
     Spatial and temporal patterns of monitored surface ozone 
concentrations are reproduced well by the modeling system on most days;
     Model performance for ozone across the full domain is 
consistent with the model performance in individual subregions;
     Aloft ozone predictions compare favorably with aircraft 
ozone data; and
     Model performance for ozone precursors, especially 
NOX, is very good.
    Confidence in underlying data bases is high. A comprehensive field 
program was conducted during the summer of 1991. This field program was 
used to collect a large quantity of air quality and meteorological data 
to support the photochemical grid modeling.
    The modeling results obtained by the LADCO States were corroborated 
with the results from other modeling studies. As part of the 
Cooperative Regional Model Evaluation (CReME), the photochemical models 
UAM-IV, UAM-V, and SAQM were applied in the Lake Michigan region. The 
supplemental analyses shows that UAM-V produces results directionally 
consistent with those produced by UAM-IV and SAQM. All three models 
concurred in showing that VOC emission reductions are generally locally 
beneficial and that local NOX emission controls are not 
beneficial in certain locations, generally within 100 to 200 kilometers 
downwind of Chicago.

B. Severity of Modeled Episodes

    Three of the four ozone episodes modeled reflect meteorological 
conditions which typically favor high ozone in the Lake Michigan area 
(when the Lake Michigan area is on the ``back-side'' of a high pressure 
system with warm temperatures, high humidity, and south-southwesterly 
winds). The fourth episode is representative of warm temperatures with 
easterly winds, conditions which generally produce lower peak ozone 
concentrations and fewer ozone standard exceedances on a per year 
basis.
    The magnitudes of the observed peak ozone concentrations at one or 
more locations within the modeling domain for the selected ozone 
episodes exceed the corresponding ozone design values for many 
locations within the region. This implies that the modeled ozone 
episodes are conservative and that attaining the ozone standard for 
these episodes should lead to attainment of the ozone standard in non-
modeled episodes and during most future ozone conducive periods.

C. Trends Analyses

    Several trends analyses have been considered. First, 10-year trends 
established by the Environmental Protection Agency based on second high 
daily maximum one-hour ozone concentrations for each year show no 
significant changes in Chicago, Grand Rapids, Gary, and Kenosha; and a 
downward trend in Racine and Milwaukee. Second, 17-year trends

[[Page 70543]]

based on the number of ozone exceedance days normalized based on the 
annual number of hot days show that the number of exceedance days is 
significantly decreasing relative to the number of hot days each year. 
Third, 15-year trends show downward trends in ozone at sites on the 
western side of Lake Michigan.
    Examination of limited morning total non-methane hydrocarbon 
concentration levels in Chicago and Milwaukee over the past 10 years 
show a significant downward trend. This downward trend is consistent 
with the calculated downward trend in VOC emissions.
    The LADCO States conclude that the weight-of-evidence demonstration 
provides additional information which verifies the directionality of 
the modeling and demonstrates the potential stringency of the modeling 
results. The States conclude this information is sufficient to support 
minor exceptions to the benchmark, supporting a demonstration of 
attainment at the higher background ozone concentrations.
    ii. Limits on the Values of Allowed Exceedances. Under this 
benchmark, the maximum modeled ozone concentration on severe days shall 
not exceed 130 ppb. The States, based on the modeled peak ozone 
concentrations, conclude this benchmark is passed for Strategy 2 with a 
maximum background ozone concentration of 70 ppb and for Strategy 4 
with a maximum background ozone concentration of 80 ppb.
    iii. Required Minimum Level of Air Quality Improvement. Under this 
benchmark, the number of grid cells with modeled peak ozone 
concentrations greater than 124 ppb must be reduced by at least 80 
percent on each day with allowed modeled ozone standard exceedances. 
The States, based on the modeled peak ozone concentrations, conclude 
this benchmark is passed for Strategy 2 with a maximum background ozone 
concentration of 80 ppb and for Strategy 4 with a maximum background 
ozone concentration of 85 ppb.
    From the above, it can be seen that benchmark i. is the most 
stringent of benchmarks in this case. Based on the statistical 
approach, coupled with a weight-of-evidence analysis, the States 
conclude that Strategy 2 with a maximum background ozone concentration 
of 70 ppb or Strategy 4 with a maximum background ozone concentration 
of 80 ppb is sufficient to attain the one-hour ozone standard by 2007.
    The States further conclude, based on both attainment demonstration 
approaches, that either Strategy 2 or Strategy 4 coupled with future 
year boundary conditions generally consistent with the impacts of the 
NOX SIP call is sufficient to attain the one-hour ozone 
standard.
5. Emission Control Strategies
What Emission Control Strategies Were Considered in the Attainment 
Demonstrations?
    LADCO selected two emission control strategies considered during 
the Lake Michigan Ozone Control Program for further attainment 
demonstration modeling (numerous emission control measures were 
initially examined). The two strategies selected are referred to as 
Strategy 2 and Strategy 4. These emission control strategies would 
apply to the ozone nonattainment areas only and are summarized as the 
following:
    a. Strategy 2. Strategy 2 includes all national emission control 
measures mandated by the CAA to be in place by 1996, including the 
emission controls needed to comply with the requirements for 15 percent 
Rate-Of-Progress (ROP) plans. Additional ROP plans for the post-1996 
period were not considered, and additional NOX emission 
controls, such as NOX Reasonably Available Control 
Technology, were not considered due to the existence of an approved 
NOX emission control waiver under section 182(f) of the 
Clean Air Act. Existing NOX emission reduction requirements, 
such as the acid rain control requirements under Title IV of the Clean 
Air Act, were considered.
    b. Strategy 4. Strategy 4 includes all Strategy 2 measures and also 
includes some additional point, area, and mobile source control 
measures in the severe ozone nonattainment areas. The additional 
controls are measures that the State could consider. The State, 
however, has not evaluated the technical feasibility or cost-
effectiveness of these measures. The measures have only been considered 
regarding their potential to reduce VOC and NOX emissions by 
2007.
    Table 3 lists the VOC and NOX emission reductions 
expected in Grid B and in the severe ozone nonattainment areas. 
Emissions control strategy components for Wisconsin are listed in Table 
4. The following acronyms are used:

RACT--Reasonably Available Control Technology
NESHAP--National Emission Standard for Hazardous Air Pollutants
MACT--Maximum Available Control Technology
I/M--Vehicle Inspection and Maintenance

      Table 3.--Emission Control Levels From Strategies 2 and 4 Grid B and Severe Ozone Nonattainment Areas
                                      [Lake Michigan Ozone Modeling Domain]
----------------------------------------------------------------------------------------------------------------
                                                     Grid B--Percent  emission      Severe nonattainment  area
                                                              change               percentage  emissions change
                    Strategy                     ---------------------------------------------------------------
                                                        VOC             NOX             VOC             NOX
----------------------------------------------------------------------------------------------------------------
2...............................................             -27             -13             -37             -11
4...............................................             -40             -19             -53             -18
----------------------------------------------------------------------------------------------------------------


            Table 4.--Emission Control Measures in Wisconsin
 
 
-------------------------------------------------------------------------
            STRATEGY 2--2007 MANDATORY CLEAN AIR ACT MEASURES
------------------------------------------------------------------------
 
POINT SOURCE VOC CONTROLS
    Asphalt Production Plants
    Industrial Adhesives
    Iron and Steel Foundries RACT
    Miscellaneous Wood Product Coating
    Degreasing Controls

[[Page 70544]]

 
    Industrial Solvent Cleanup RACT
    Large Gasoline Storage
    Offset Lithography
    Plastic Parts Coating Tightening
    Wood Furniture Coating RACT
    Screen Printing RACT
    Yeast Manufacturing RACT
POINT SOURCE NOX CONTROLS
    Acid Rain Phase I NOX Limits
AREA SOURCE VOC CONTROLS
    Automobile Refinishing
    Degreasing Controls
    Solid Waste Toxic Substance Disposal Facility MACT
    Stage II Vehicle Refueling Vapor Recovery
    Reformulated Gasoline Use in Off-Road Vehicles
    Traffic Marking Reformulation or Solvent Control
    Wood Furniture Coating Tightening
    Architectural and Industrial Maintenance Coatings
    Municipal Waste Landfills
    Stage I Refueling Reductions Due To Use of Reformulated Gasoline
    Gasoline Tank Truck Leak Reductions Due To Use of Reformulated
     Gasoline
    Underground Tank Breathing Losses and Leak Control Due To
    Use of Reformulated Gasoline
    Commercial/Consumer Solvent Reformulation or Elimination
    Off-Road Engine Standards
    On-Board Vehicle Controls
MOBILE SOURCE CONTROLS
    Tier I Light-Duty Vehicle Standards
    Reformulated Gasoline--Phase II (Class C)
    Enhanced I/M (no NOX cut-points)
    Clean Fuel Fleets
    Current Transportation Improvement Program/Build Scenario Long Range
     Transportation Plan, including the following elements:
         Full implementation of adopted Land Use Plan and
         promotion of land use and urban design elements that encourage
         alternatives to automobile commuting
         Public Transit Service Improvements with a Phase-In 75
         Percent Increase in Service by 2010
         Transportation Demand Management Measures that Support
         Employee Commute Options Program Goals, including: Ridesharing;
         telecommuting; Transportation Management Associations; and
         Alternative Work Schedule Promotion
         Freeway Traffic Management Plan Implementation
         Highway Improvements--Congestion Mitigation
2010  Transportation System Plan Recommended Transportation Control
 Measures
------------------------------------------------------------------------
                STRATEGY 4--2007 MANDATORY MEASURES PLUS
------------------------------------------------------------------------
 
All Strategy 2 measures plus:
POINT SOURCE VOC CONTROLS
    Improved Rule Effectiveness
    Phased Emission Reduction Program
POINT SOURCE NOX CONTROLS
    Phase II Acid Rain NOX Limits
AREA SOURCE VOC CONTROLS
    Agricultural Pesticides Application
    Degreasing Controls
    Improved Rule Effectiveness
    Offset Lithography
    Petroleum Dry Cleaning
    Small Engine Buy-Back Program
    Stage II Vehicle Refueling--Eliminate Small Business
    Exemption
MOBILE SOURCE CONTROLS
    California Low Emission Vehicle Controls
    Specific Vehicle I/M (no NOX cut-points)
    Reformulated Gasoline--Phase II (Class B)
------------------------------------------------------------------------

Has the State Adopted a Selected Emission Control Strategy?
    The State has not selected either emissions control strategy as the 
official, adopted emissions control strategy of the Phase II ozone 
attainment demonstration. The State, however, has adopted and developed 
regulations for many of the emission control measures contained in the 
two emission control strategies, and particularly for the controls 
contained in Strategy 2. Some of the emission control measures in 
Strategy 4, however, have not been adopted. For example, Wisconsin has 
not adopted a Phased Emission Reduction Program (capped emissions with 
declining emission caps) and has not adopted major agricultural 
pesticide application restrictions.

[[Page 70545]]

6. Transportation Conformity
Did the State Address Transportation Conformity in the Submittals?
    Wisconsin has not specifically addressed transportation conformity 
or associated mobile source emission budgets in the attainment 
demonstration submittals and no such mobile source emission budget has 
been adopted as part of the Phase II submittal.
7. State Commitments
Are There Any State Commitments for Further Analyses and Air Quality 
Plans Addressing a Final Ozone Attainment Demonstration for the One-
Hour Ozone Standard?
    Wisconsin believes that, with the level of NOX emission 
reductions consistent with the NOX SIP call and considering 
the VOC emission reductions from the 15 percent (1996) and 9 percent 
(post-1996) ROP plans, little or no additional VOC emission reductions 
are necessary to provide for attainment of the one-hour ozone standard. 
Wisconsin has committed to submit a final plan, including additional 
modeling and adopted emission control regulations, to achieve 
attainment of the one-hour standard and to meet post-1999 ROP 
requirements. This plan with all necessary control measures for 
attainment and ROP to the attainment year will be submitted to EPA no 
later than the end of 2000. The revised modeling submitted by December 
2000 will fully consider the impact of NOX regional 
reductions and the adopted control measures submitted in December 2000 
will reflect those needed in light of the effect of the regional 
NOX reductions on the modeled attainment demonstration. If 
additional VOC control measures are needed, Wisconsin will revise the 
SIP to include the necessary regulations.
    Wisconsin commits to implement the emission control programs on a 
schedule necessary to meet ROP requirements and to implement 
NOX emission controls consistent with the compliance 
schedule contained in the final NOX SIP call.

B. Environmental Protection Agency Review of the Submittals

1. Adequacy of the State's Demonstration of Attainment
Did the State Adequately Document the Techniques and Data Used To 
Derive the Modeling Input Data and Modeling Results of the Analyses?
    The Phase I submittals from the States, submitted in June 1996, 
thoroughly documented the techniques and data used to derive the 
modeling input data. The Phase II submittal adequately summarized the 
modeling outputs and the conclusions drawn from these model outputs.
Did the Modeling Procedures and Input Data Used Comply With the CAA and 
EPA Guidelines?
    Yes.
Did the States Adequately Demonstrate Attainment of the Ozone Standard?
    Wisconsin, in accordance with EPA's December 1997 guidance, has 
demonstrated that attainment of the standard is achievable provided 
sufficient reductions in background ozone concentrations (and 
background ozone precursor concentrations) occur as a result of the 
implementation of regional NOX emission controls under the 
NOX SIP call. Wisconsin, however, has not selected a 
specific final emission control strategy that would achieve attainment 
of the one-hour ozone standard. As described earlier, Wisconsin will 
select a control strategy for purposes of establishing a motor vehicle 
conformity budget. A subsequent emission control attainment strategy 
will be selected when the LADCO States submit a final attainment 
demonstration in December 2000.
Does the Weight-of-Evidence Test Support the States' Conclusions 
Regarding the Attainment Demonstration?
    The documented WOE analyses support the conclusions of the 
deterministic test and the statistical test. Both the deterministic 
test and the statistical test lead to similar conclusions regarding the 
1-hour ozone standard attainment demonstration. Both deterministic and 
statistical tests, as supplemented by a WOE analysis, show that 
attainment can be achieved with local emissions controls already 
implemented coupled with significant reductions in transported ozone 
and ozone precursors.
2. Adequacy of the Emissions Control Strategy
Has an Adopted Emissions Control Strategy Been Adequately Documented?
    No. The State has not adopted a final emissions control strategy 
for attainment of the one-hour ozone standard. The State, however, has 
demonstrated that significant reductions in transported ozone and 
NOX will be necessary to attain the 1-hour standard. These 
reductions are expected to occur as a result of the implementation of 
regional NOX emission reductions. All three of the LADCO 
States, including Wisconsin, are expected to submit SIPs to address 
EPA's NOX SIP call or to implement alternative regional 
NOX controls within their States.
Is the Emission Control Strategy Acceptable?
    No. The State must select an emissions control strategy that is 
consistent with attainment in order to establish a motor vehicle 
emissions budget. The State must do so in sufficient time for EPA to 
find the motor vehicle emissions budget adequate by May 31, 2000 (See 
Table in Section II.D.) The State has committed to adopt and submit the 
final emission control strategy associated with a revised modeling 
analysis by December 2000.
3. State Commitments
Are the State Commitments for Future Analyses and Finalization of the 
Attainment Demonstration Acceptable?
    Yes. EPA's December 1997 policy provides that severe nonattainment 
area States must submit the control measures necessary to attain the 
NAAQS and meet post-1999 ROP no later than December 2000. Wisconsin's 
commitments to provide additional modeling and to adopt and submit the 
post-1999 ROP plan (the post-1996 ROP plan, covering the period of 1997 
through 1999, is currently under review by the Environmental Protection 
Agency) and any additional measures needed for attainment by December 
2000 are acceptable.
4. Relationship To Other Requirements
Will the Future Analyses Adequately Address the Impacts of the 
NOX SIP Call?
    Yes. The LADCO States have made it very clear that the one-hour 
ozone standard will be difficult to attain without regional 
NOX emission reductions and that the final demonstration of 
attainment will incorporate the States' best estimates of the impacts 
of the NOX SIP.
Has the State Specified and Adopted Acceptable Transportation 
Conformity Motor Vehicle Emission Budgets?
    No. The State has not selected a specific emission control 
strategy. The State must select a control strategy that is consistent 
with the attainment. The State will need to establish a motor vehicle 
emissions budget based on the selected strategy and will need to submit 
the budget in time for EPA to find the budget adequate by May 31, 2000.

[[Page 70546]]

C. Summary

Overall, Is Wisconsin's Ozone Attainment Demonstration Acceptable?
    Wisconsin has generally met the requirements of the EPA December 
1997 ozone attainment demonstration guidance, with the exception of 
selecting an emission control strategy. EPA will not take final action 
conditionally approving the submission unless the State selects an 
emissions control strategy and submits a motor vehicle emissions budget 
that EPA may find adequate by May 31, 2000.
What Portions of the Attainment Demonstration Need Additional Work and 
Consideration for Purposes of a Final Attainment Demonstration?
    The following items need further consideration in the final ozone 
attainment demonstration:
    1. A final modeled demonstration of attainment that considers the 
impacts of the regional NOX emission reductions, local 
control measures, and NOX emissions control waiver (if 
maintained);
    2. Adoption and submission of CAA measures, including VOC RACT for 
the following categories: Plastic parts coating, industrial cleanup 
solvents, and ink manufacturing, and adoption and submission of 
measures relied on in the final modeled attainment demonstration;
    3. Motor vehicle emission budgets, including both VOC and 
NOX emissions.
    The EPA has found that the motor vehicle emissions budget in the 
attainment demonstration submitted for the Milwaukee-Racine is 
inadequate for conformity purposes. The EPA is proposing to 
conditionally approve the attainment demonstration SIP if the State 
corrects the deficiencies that cause the motor vehicle emissions budget 
to be inadequate and, alternatively, to disapprove it if Wisconsin does 
not correct the deficiencies. If Wisconsin submits a revised attainment 
demonstration, EPA will re-open the comment period for this proposal in 
order to take comment on whether to approve the new submission.

III. Proposed Action

    The Environmental Protection Agency proposes to issue a final 
conditional approval of the ozone attainment demonstration.
    The State already committed to do the following in the April 1998 
ozone attainment demonstration: (1) Perform and submit a final modeled 
ozone attainment demonstration by December 2000; (2) adopt and submit a 
specific emissions control strategy, including adopted control 
measures, adequate to attain the 1-hour ozone NAAQS in the ozone 
nonattainment area and throughout the ozone modeling domain by December 
2000; (3) adopt and submit control measures necessary to meet ROP from 
1999 until the attainment year and the associated target calculations. 
For EPA to issue a final conditional approval the State will need to 
take the following steps in sufficient time for EPA to determine by May 
31, 2000 that the state has an adequate motor vehicle emissions budget: 
(1) Select a control strategy consistent with its current modeling 
analysis; (2) adopt and submit an adequate motor vehicle emissions 
budget consistent with the selected strategy; (3) commit to adopt and 
submit certain VOC RACT rules by December 2000; and (4) commit to 
perform a mid-course review.
    Because many States may shortly be submitting revised 
demonstrations with revised motor vehicle emission budgets, EPA is 
providing a 60 day comment period on this proposed rule. If Wisconsin 
submits a revised attainment demonstration, EPA will place the 
revisions in the docket for this rulemaking and will post a notice on 
EPA's website at www.epa.gov/oms/traq. By posting notice on the 
website, EPA will also initiate the adequacy process.
    If the State does not take one or more of the actions listed above 
in time for EPA to determine the conformity budget adequate by May 31, 
2000, or if the State submits a motor vehicle emissions budget that EPA 
determines is not adequate, EPA will disapprove the attainment 
demonstration submission for the Milwaukee-Racine area.
    If EPA issues a final conditional approval of the State's 
submission, the conditional approval will convert to a disapproval if 
the State does not adopt and submit a complete SIP submission with the 
following four elements by December 31, 2000: (1) A final revised 
modeling analysis that fully assesses the impacts of regional 
NOX reductions, models a specific local emissions reduction 
strategy, and reconsiders the effectiveness of the NOX 
waiver; (2) VOC rules and regulations for the plastic parts coating, 
industrial cleanup solvents, and ink manufacturing; (3) control 
measures necessary to meet the ROP requirement from 1999 until the 
attainment year, including target calculations.
    If the State makes a complete submission with all of the above 
elements by December 31, 2000, EPA will propose action on the new 
submissions for the purpose of determining whether to issue a final 
full approval of the attainment demonstration.
What Are the Consequences of State Failure?
    This section explains the CAA consequences of State failure to meet 
the time frames and terms described generally in this notice. The CAA 
provides for the imposition of sanctions and the promulgation of a 
federal implementation plan if States fail to submit a required plan, 
submit a plan that is determined to be incomplete or if EPA disapproves 
a plan submitted by the State (We using the phrase ``failure to 
submit'' to cover both the situation where a State makes no submission 
and the situation where the State makes a submission that we find is 
incomplete in accordance with section 110(k)(1)(B) and 40 CFR part 51, 
Appendix V.) For purposes of sanctions, there are no sanctions clocks 
in place based on a failure to submit. Thus, the description of the 
timing of sanctions, below, is linked to a potential disapproval of the 
State's submission.
What Are the CAA's Provisions for Sanctions?
    If EPA disapproves a required SIP, such as the attainment 
demonstration SIPs, section 179(a) provides for the imposition of two 
sanctions. The first sanction would apply 18 months after EPA 
disapproves the SIP if the State fails to make the required submittal 
which EPA proposes to fully or conditionally approve within that time. 
Under EPA's sanctions regulations, 40 CFR 52.31, the first sanction 
would be 2:1 offsets for sources subject to the new source review 
requirements under section 173 of the CAA. If the State has still 
failed to submit a SIP for which EPA proposes full or conditional 
approval 6 months after the first sanction is imposed, the second 
sanction will apply. The second sanction is a limitation on the receipt 
of Federal highway funds. EPA also has authority under section 110(m) 
to a broader area, but is not proposing to take such action today.
What Are the CAA's FIP Provisions If a State Fails To Submit a Plan?
    In addition to sanctions, if EPA finds that a State failed to 
submit the required SIP revision or disapproves the required SIP 
revision EPA must promulgate a FIP no later than 2 years from the date 
of the finding if the deficiency has not been corrected. The attainment 
demonstration SIPs on which EPA is taking action today were originally 
due in November 1994. However, through a

[[Page 70547]]

series of policy memoranda, EPA recognized that States had not 
submitted attainment demonstrations and were constrained to do so until 
ozone transport had been further analyzed. As provided in the 
Background, above, EPA provided for States to submit the attainment 
demonstration SIPs in two phases. In June 1996, EPA made findings that 
ten States and the District of Columbia had failed to submit the phase 
I SIPs for nine nonattainment areas. 61 FR 36292 (July 10, 1996). In 
addition on May 19, 1997, EPA made a similar finding for Pennsylvania 
for the Philadelphia area. 62 FR 27201.
    In July 1998, several environmental groups filed a notice of 
citizen suit, alleging that EPA had outstanding sanctions and FIP 
obligations for the serious and severe nonattainment areas on which EPA 
is proposing action. These groups filed a lawsuit in the Federal 
District Court for the District of Columbia on November 8, 1999.

IV. Administrative Requirements

A. Executive Order (E.O.) 12866

    The Office of Management and Budget (OMB) has exempted this 
regulatory action from review under E.O. 12866, entitled ``Regulatory 
Planning and Review.''

B. Executive Order 13045

    Executive Order 13045, entitled ``Protection of Children From 
Environmental Health Risks and Safety Risks'' (62 FR 19885, April 23, 
1997), applies to any rule that the EPA determines (1) is 
``economically significant,'' as defined under Executive Order 12866, 
and (2) the environmental health or safety risk addressed by the rule 
has a disproportionate effect on children. If the regulatory action 
meets both criteria, the Agency must evaluate the environmental health 
or safety effects of the planned rule on children and explain why the 
planned regulation is preferable to other potentially effective and 
reasonably feasible alternatives considered by the Agency.
    This final rule is not subject to E.O. 13045 because it does not 
involve decisions intended to mitigate environmental health and safety 
risks.

C. Executive Order 13084

    Under E.O. 13084, EPA may not issue a regulation that is not 
required by statute, that significantly affects or uniquely affects the 
communities of Indian tribal governments, and that imposes substantial 
direct compliance costs on those communities, unless the Federal 
government provides the funds necessary to pay the direct compliance 
costs incurred by the tribal governments. If the mandate is unfunded, 
EPA must provide to the Office of Management and Budget, in a 
separately identified section of the preamble to the rule, a 
description of the extent of EPA's prior consultation with 
representatives of affected tribal governments, a summary of the nature 
of their concerns, and a statement supporting the need to issue the 
regulation. In addition, Executive Order 13084 requires EPA to develop 
an effective process permitting elected and other representatives of 
Indian tribal governments ``to provide meaningful and timely input in 
the development of regulatory policies on matters that significantly or 
uniquely affect their communities.'' Today's rule does not 
significantly or uniquely affect the communities of Indian tribal 
governments. This action does not involve or impose any requirements 
that affect Indian Tribes. Accordingly, the requirements of section 
3(b) of E.O. 13084 do not apply to this rule.

D. Executive Order 13132

    Executive Order 13132, Federalism (64 FR 43255, August 10, 1999), 
revokes and replaces Executive Orders 12612 (Federalism) and 12875 
(Enhancing the Intergovernmental Partnership). Executive Order 13132 
requires EPA to develop an accountable process to ensure ``meaningful 
and timely input by State and local officials in the development of 
regulatory policies that have federalism implications.'' ``Policies 
that have federalism implications'' is defined in the Executive Order 
to include regulations that have ``substantial direct effects on the 
States, on the relationship between the national government and the 
States, or on the distribution of power and responsibilities among the 
various levels of government.'' Under Executive Order 13132, EPA may 
not issue a regulation that has federalism implications, that imposes 
substantial direct compliance costs, and that is not required by 
statute, unless the Federal government provides the funds necessary to 
pay the direct compliance costs incurred by State and local 
governments, or EPA consults with State and local officials early in 
the process of developing the proposed regulation. EPA also may not 
issue a regulation that has federalism implications and that preempts 
State law unless the Agency consults with State and local officials 
early in the process of developing the proposed regulation.
    This rule will not have substantial direct effects on the States, 
on the relationship between the national government and the States, or 
on the distribution of power and responsibilities among the various 
levels of government, as specified in Executive Order 13132 (64 FR 
43255, August 10, 1999), because it merely approves a State rule 
implementing a federal standard, and does not alter the relationship or 
the distribution of power and responsibilities established in the Clean 
Air Act. Thus, the requirements of section 6 of the Executive Order do 
not apply to this rule.

E. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency 
to conduct a regulatory flexibility analysis of any rule subject to 
notice and comment rulemaking requirements unless the agency certifies 
that the rule will not have a significant economic impact on a 
substantial number of small entities. Small entities include small 
businesses, small not-for-profit enterprises, and small governmental 
jurisdictions. This proposed rule will not have a significant impact on 
a substantial number of small entities because SIP approvals under 
section 110 and subchapter I, part D of the Clean Air Act do not create 
any new requirements but simply approve requirements that the State is 
already imposing. Therefore, because the Federal SIP approval does not 
create any new requirements, I certify that this action will not have a 
significant economic impact on a substantial number of small entities. 
Moreover, due to the nature of the Federal-State relationship under the 
Clean Air Act, preparation of a flexibility analysis would constitute 
Federal inquiry into the economic reasonableness of state action. The 
Clean Air Act forbids EPA to base its actions concerning SIPs on such 
grounds. Union Electric Co. v. U.S. EPA, 427 U.S. 246, 255-66 (1976); 
42 U.S.C. 7410(a)(2).
    If the conditional approval is converted to a disapproval under 
section 110(k), based on the State's failure to meet the commitment, it 
will not affect any existing State requirements applicable to small 
entities. Federal disapproval of the State submittal does not affect 
State-enforceability. Moreover, EPA's disapproval of the submittal does 
not impose any new requirements. Therefore, I certify that such a 
disapproval action will not have a significant economic impact on a 
substantial number of small entities because it would not remove 
existing

[[Page 70548]]

requirements nor would it substitute a new Federal requirement.
    The EPA's alternative proposed disapproval of the State request 
under section 110 and subchapter I, part D of the Act would not affect 
any existing requirements applicable to small entities. Any pre-
existing Federal requirements would remain in place after this 
disapproval. Federal disapproval of the State submittal does not affect 
State-enforceability. Moreover EPA's disapproval of the submittal would 
not impose any new Federal requirements. Therefore, I certify that the 
proposed disapproval would not have a significant impact on a 
substantial number of small entities.

F. Unfunded Mandates

    Under section 202 of the Unfunded Mandates Reform Act of 1995 
(``Unfunded Mandates Act''), signed into law on March 22, 1995, EPA 
must prepare a budgetary impact statement to accompany any proposed or 
final rule that includes a Federal mandate that may result in estimated 
annual costs to State, local, or tribal governments in the aggregate; 
or to private sector, of $100 million or more. Under section 205, EPA 
must select the most cost-effective and least burdensome alternative 
that achieves the objectives of the rule and is consistent with 
statutory requirements. Section 203 requires EPA to establish a plan 
for informing and advising any small governments that may be 
significantly or uniquely impacted by the rule.
    EPA has determined that the proposed approval action does not 
include a Federal mandate that may result in estimated annual costs of 
$100 million or more to either State, local, or tribal governments in 
the aggregate, or to the private sector. This Federal action approves 
pre-existing requirements under State or local law, and imposes no new 
requirements. Accordingly, no additional costs to State, local, or 
tribal governments, or to the private sector, result from this action.
    Sections 202 and 205 do not apply to the proposed disapproval 
because the proposed disapproval of the SIP submittal would not, in and 
of itself, constitute a Federal mandate because it would not impose an 
enforceable duty on any entity. In addition, the Act does not permit 
EPA to consider the types of analyses described in section 202 in 
determining whether a SIP submittal meets the CAA. Finally, section 203 
does not apply to the proposed disapproval because it would affect only 
the State of Wisconsin, which is not a small government.

G. National Technology Transfer and Advancement Act

    Section 12 of the National Technology Transfer and Advancement Act 
(NTTAA) of 1995 requires Federal agencies to evaluate existing 
technical standards when developing new regulations. To comply with 
NTTAA, the EPA must consider and use ``voluntary consensus standards'' 
(VCS) if available and applicable when developing programs and policies 
unless doing so would be inconsistent with applicable law or otherwise 
impractical.
    EPA believes that VCS are inapplicable to this action. Today's 
action does not require the public to perform activities conducive to 
the use of VCS.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Hydrocarbons, 
Nitrogen dioxide, Ozone.

    Authority: 42 U.S.C. 7401 et seq.

    Dated: November 30, 1999.
Francis X. Lyons,
Regional Administrator, Region 5.
[FR Doc. 99-31722 Filed 12-15-99; 8:45 am]
BILLING CODE 6560-50-P