[Federal Register Volume 64, Number 241 (Thursday, December 16, 1999)]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-31722]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
Approval and Promulgation of Implementation Plans; Wisconsin;
AGENCY: Environmental Protection Agency.
ACTION: Proposed rule.
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,
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
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-
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
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.
\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.
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
\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.
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
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
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.
\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'').
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.
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.
\6\ The initial, ``ramp-up'' days for each episode are excluded
from this determination.
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
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
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
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
A motor vehicle emissions budget which can be determined by EPA to
be adequate for conformity purposes.
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
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
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
--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
--9% ROP plan through 1999
--Clean fuels program or substitute
--Enhanced monitoring Photochemical Assessment Monitoring Stations
--Stage II vapor recovery
\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
--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)
--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
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
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
\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
\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
\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
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
--Submit revised SIP & motor vehicle
emissions budget by 12/31/00 if
additional measures (due by 12/31/00)
affect the motor vehicle emissions
--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
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
--State revises and submits SIP & motor
vehicle emissions budget to account for
Tier 2 reductions as needed.3
12/31/03..................... State submits to EPA results of mid-
\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
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.
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
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://
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/
4. Memorandum, ``Extension of Attainment Dates for Downwind
Transport Areas,'' issued July 16, 1998. Web site: http://www.epa.gov/
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:
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,
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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.
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
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
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
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
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
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
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
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
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
5. Emission Control Strategies
What Emission Control Strategies Were Considered in the Attainment
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
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
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
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
Iron and Steel Foundries RACT
Miscellaneous Wood Product Coating
Industrial Solvent Cleanup RACT
Large Gasoline Storage
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
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
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
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
Improved Rule Effectiveness
Petroleum Dry Cleaning
Small Engine Buy-Back Program
Stage II Vehicle Refueling--Eliminate Small Business
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.
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
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.
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
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
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
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
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
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
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
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
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